Details of a Researcher - UENO Kazuhide

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work

Nanolayer-Encapsulated Stretchable Liquid-Metal Sheets for Thermal Management

Daisuke Kuse, Yudai Kaneko, Ryohei Fujita, Tatsuhiro Horii, Daishi Shiojiri, Yuta Ozawa, Kyohei Nag … Show more authors

Advanced Functional Materials 2026.2 [Reviewed]

Polymer-Assisted Supercooled Lithium Salts: Nonflammable Single-Ion Conducting Liquid Electrolytes for Next-Generation Batteries

Language：English Publishing type：Research paper (scientific journal) Single Work

Sudoh, T; Shigenobu, K; Philippi, F; Niwamura, C; Ugata, Y; Matsuyama, Y; Kondou, S; Tsuzuki, S; Sa … Show more authors

ADVANCED ENERGY MATERIALS 16 ( 5 ) 2026.2 [Reviewed]

Grafting-Engineered Interfacial Desolvation Dynamics: A Universal Strategy for Low-Temperature Li-Metal Batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ma, C; Cui, WF; Zhang, QX; Yao, CY; Zhou, SZ; Watanabe, M; Ueno, K; Ding, Y; Liu, XZ

ADVANCED FUNCTIONAL MATERIALS 36 ( 7 ) 2026.1

Low-melting, ether-functionalised lithium salts for enhanced ion transport in molten salt electrolytes

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Matsuyama, Y; Philippi, F; Sudoh, T; Pugh, D; Sawayama, S; Fujii, K; Tsuzuki, S; Hossain, MS; Ueno, … Show more authors

ENERGY ADVANCES 4 ( 12 ) 1438 - 1442 2025.12 [Reviewed]

Essential oil-derived decomposable polymers via cycloaddition polymerization of silyl ether-linked phenylpropanoids

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Joint Work

Nagaya, R; Seko, T; Okamoto, K; Ueno, K; Atobe, M; Shida, N

NATURE COMMUNICATIONS 16 ( 1 ) 2025.11 [Reviewed]

Design of Liquid Electrolytes for Next-Generation Batteries Based on Analysis of Ion Dynamics

Language：English Publishing type：Research paper (scientific journal) Joint Work

SHIGENOBU Keisuke, TSUZUKI Seiji, UENO Kazuhide, SHINODA Wataru

BUNSEKI KAGAKU 74 ( 9 ) 427 - 436 2025.9

Conformational Flexibility of Solvent Molecules Enables Li-Ion Hopping in Highly Concentrated Electrolytes

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society for Analytical Chemistry Joint Work

Lithium secondary batteries are significantly involved in the realization of a decarbonized society. Improvements in battery performance, such as increased capacity and rapid charge/discharge, are key to success, and a redesign of the liquid electrolytes that can facilitate excellent Li-ion transport is required. To understand the ion transport of liquid electrolytes, a new approach that includes dynamic ion–ion and ion–solvent correlations is much preferable to the conventional ideal/diluted solution theory. This article clarifies the properties of Li-ion transport, particularly ionic conductivity and the Li-ion transference number, combining the concentrated electrolyte solution theory with the Onsager transport coefficients. Moreover, it proposes designing liquid electrolytes based on an analysis of ion dynamics.

Sawayama, S; Kondou, S; Ueno, K; Fujii, K

JOURNAL OF PHYSICAL CHEMISTRY B 129 ( 31 ) 7995 - 8001 2025.8

Discrepant lithium transference numbers due to heterogeneous speciation

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Philippi, F; Matsuyama, Y; Buyting, S; Sudoh, T; Shigenobu, K; Shinoda, W; Schoenhoff, M; Watanabe, … Show more authors

PHYSICAL CHEMISTRY CHEMICAL PHYSICS 27 ( 28 ) 15185 - 15195 2025.7 [Reviewed]

Weakly coordinating monoether-based concentrated electrolytes: effects of frustrated Li ion coordination on ion transport and Li metal battery performance

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ishikawa, T; Sudoh, T; Shigenobu, K; Wada, G; Tsuzuki, S; Aoki, Y; Sharif, HM; Dokko, K; Watanabe, … Show more authors

ELECTROCHIMICA ACTA 527 2025.7 [Reviewed]

Self-assembled Cationic Surfactant-based Electrolytes for Rechargeable Aqueous Zinc Metal Batteries

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work

SHEN Guohong, KONDOU Shinji, NAKAGAKI Hiroki, WADA Gakuto, WATANABE Masayoshi, DOKKO Kaoru, UENO Ka … Show more authors

Electrochemistry 93 ( 3 ) 037008 - 037008 2025.3 [Reviewed]

Solvation structure of Li+ in highly concentrated LiTFSA–DMSO solutions studied by means of neutron diffraction with 6Li/7Li isotopic substitution method

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人　電気化学会 Joint Work

Surfactants possess unique properties in bulk solutions and at interfaces, naturally forming self-assembled structures. Herein, cetyltrimethylammonium trifluoroacetate (CTATFA) was incorporated into aqueous electrolytes as a cationic surfactant to enhance their ionic conductivity and electrochemical stability. The presence of CTATFA widened the electrochemical stability windows of both Li-based and Zn-based electrolytes. The Zn-based electrolyte exhibited high ionic conductivity and low viscosity in the bulk solution. In a Zn symmetric cell, the electrolyte containing 1 M Zn(TFA)2-0.5 M CTATFA demonstrated excellent Zn plating/stripping reversibility for over 800 h at 1 mAh cm−2 and 1 mA cm−2. A Zn-Cu cell with 1 M Zn(TFA)2-0.5 M CTATFA exhibited excellent reversibility, achieving over 300 plating/stripping cycles at 5 mA cm−2 and 5 mAh cm−2. The Zn/MnO2 cell using the Zn-based electrolyte also demonstrated a specific capacity of 105 mAh g−1 over 750 cycles at a current density of 0.5 A g−1. This study provides insight into the design of high-performance aqueous electrolytes based on the self-assembly and surface adsorption of cationic surfactants.

Kameda, Y; Amo, Y; Usuki, T; Umebayashi, Y; Watanabe, H; Ueno, K; Ikeda, K; Honda, T; Otomo, T

BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 98 ( 3 ) 2025.3 [Reviewed]

Sulfolane-Based Gel Polymer Electrolytes Enhanced by 2D Boron Nitride Nanosheets for Optimized Ion Dynamics and Stability in Lithium Metal Batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ma, C; Kojitsu, M; Fujimoto, H; Tsuzuki, S; Liu, XZ; Watanabe, M; Ueno, K

ACS APPLIED POLYMER MATERIALS 7 ( 5 ) 3296 - 3308 2025.2 [Reviewed]

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work

Lithium metal batteries (LMBs) offer tremendous potential due to their high energy density, but practical applications are limited by challenges such as dendrite formation, safety risks, and interfacial instability. This study introduces a composite gel polymer electrolyte (GPE) that systematically integrates sulfolane-based highly concentrated electrolytes (HCEs) with two-dimensional hexagonal boron nitride nanosheets (BNNs). Through advanced experimental characterizations, electrochemical measurements, and theoretical calculations, the composite GPE is shown to achieve enhanced mechanical strength, thermal stability, and superior Li ion transport properties. The incorporation of BNNs not only reinforces the electrolyte matrix but also facilitates selective Li ion transport via strong interactions between Li ions and the filler, as validated by theoretical studies. The optimized composite GPE demonstrates outstanding electrochemical performance, achieving a high ionic conductivity of 0.7 × 10–3 S cm–1 at 30 °C and stable cycling for over 1000 h in Li/Li symmetric cells and more than 300 cycles in Li/LiFePO4 cells, along with excellent rate capabilities. This work provides a comprehensive strategy for addressing the critical limitations of LMBs and establishes a robust framework for developing next-generation high-performance solid-state battery systems.

Interfacially-localized high-concentration electrolytes for high-performance rechargeable aqueous lithium-ion batteries

Guohong Shen, Shinji Kondou, Gakuto Wada, Hiroki Nakagaki, Masayoshi Watanabe, Kaoru Dokko, Kazuhid … Show more authors

EES Batteries 1 273 - 286 2025.1 [Reviewed] [Invited]

Localized High-Concentration Binary Salt Electrolytes with Suppressed Li2Sx Solubility to Achieve Stable Li–S Pouch Cells with High Sulfur-Loading Cathodes under Lean Electrolyte Conditions

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work

Liu, JL; Ghosh, A; Kondou, S; Li, SL; Ueno, K; Dokko, K; Watanabe, M

ACS APPLIED ENERGY MATERIALS 8 ( 3 ) 1570 - 1579 2025.1 [Reviewed]

Imidazolium-based Ionic Liquid Electrolytes with Bis(fluorosulfonyl)imide Anions for Lithium Metal Anodes: Effects of Salt Concentration and Solvent Dilution

Language：English Publishing type：Research paper (scientific journal) Joint Work

Murai, J; Ueno, K

ELECTROCHEMISTRY 93 ( 11 ) 117003 - 117003 2025

Design of Liquid Electrolytes for Next-Generation Batteries Based on Analysis of Ion Dynamics

Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人　電気化学会 Joint Work

Ionic liquids (ILs) are attractive electrolytes for Li metal batteries because of their non-volatility, non-flammability, and wide electrochemical stability window. Among them, 1-ethyl-3-methylimidazolium (EMI)-based ILs exhibit high ionic conductivity but suffer from limited reductive stability, and their compatibility with Li metal anodes remains insufficiently explored in the literature. Herein, we report a systematic investigation of binary mixture electrolytes with bis(fluorosulfonyl)imide (FSI) anions, [EMI][FSI]–LiFSI, for Li metal anodes. Increasing the LiFSI concentration improves the Li deposition/dissolution Coulombic efficiency through robust FSI-derived solid electrolyte interphase (SEI) formation and a positive shift in the Li deposition/dissolution potential, which together contribute to the suppression of EMI+ decomposition. Furthermore, solvent dilution reveals contrasting effects: coordinating dimethoxyethane (G1) weakens the Li+–FSI− interactions and reduces the Coulombic efficiency, whereas the non-coordinating hydrofluoroether (HFE) preserves the interfacial stability while lowering the viscosity. These findings establish EMI-based ILs as a promising class of non-flammable electrolytes, providing an optimal design strategy for achieving highly reversible and safe Li metal batteries.

Shigenobu, K; Tsuzuki, S; Shinoda, W; Ueno, K

BUNSEKI KAGAKU 74 ( 9 ) 427 - 436 2025 [Reviewed]

ALL PRINTED LITHIUM ION BATTERY WITH LIQUID METAL PACKAGE

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ozawa, Y; Kuse, D; Funahashi, M; Nagatake, K; Takano, T; Ueno, K; Ota, H

2025 IEEE 38TH INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, MEMS 604 - 606 2025

Poly(Ionic Liquid) Electrolytes at an Extreme Salt Concentration for Solid-State Batteries

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Kondou, S; Abdullah, M; Popov, I; Martins, ML; O'Dell, LA; Ueda, H; Makhlooghiazad, F; Nakanishi, A … Show more authors

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 146 ( 48 ) 33169 - 33178 2024.11 [Reviewed]

Ionic fluids out of equilibrium: electrodeposition, dissolution, electron transfer, driving forces: general discussion

Language：English Publishing type：Research paper (scientific journal) Joint Work

Abbott, AP; Atkin, R; Gomes, MC; Dufrêche, JF; Elgar, CE; Fung, YKC; Goloviznina, K; Grimaud, A; Ha … Show more authors

FARADAY DISCUSSIONS 253 ( 0 ) 407 - 425 2024.10

Bubble Printing of Liquid Metal Colloidal Particles for Conductive Patterns

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Mukai, M; Kobayashi, T; Sato, M; Asada, J; Ueno, K; Furukawa, T; Maruo, S

NANOMATERIALS 14 ( 20 ) 2024.10 [Reviewed]

Impact of Li Ion Transport Properties on Reversibility of Li Metal Electrode in Glyme-Based Electrolytes

Language：English Publishing type：Research paper (scientific journal) Joint Work

Murai, J; Ishikawa, T; Wada, G; Dokko, K; Watanabe, M; Ueno, K

CHEMELECTROCHEM 11 ( 14 ) 2024.7 [Reviewed]

Impact of Li Ion Transport Properties on Reversibility of Li Metal Electrode in Glyme-Based Electrolytes

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work

Murai Junichi, Ishikawa Toru, Wada Gakuto, Dokko Kaoru, Watanabe Masayoshi, Ueno Kazuhide

ChemElectroChem Early Access 2024.6

R2R-Based Continuous Production of Patterned and Multilayered Elastic Substrates with Liquid Metal Wiring for Stretchable Electronics

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work

The demand for innovative batteries with high specific energy densities has increased. Li-metal batteries employing Li-metal anodes, regarded as the ultimate anodes with a high theoretical capacity, have been extensively studied over the past few decades. However, the poor reversibility and safety concerns regarding Li-metal anodes remain unresolved. The importance of the electrode/electrolyte interface, especially the solid electrolyte interphase (SEI), for achieving reversibility of Li metal anodes has been extensively studied. Herein, we focused on the impact of the Li ion transport properties in oligoether (glyme)-based electrolytes on the deposition/dissolution efficiency of Li metal anodes. Analysis of the low-frequency impedance spectra of Li-plated Cu/Li cells revealed that the diffusion resistance of Li ions (Rdiffusion) may be a dominant contributor to the internal resistance of the cells employing glyme-based electrolytes. A higher Rdiffusion in poor-mass-transport electrolytes with a lower Li ion transference number resulted in larger polarization during Li deposition/dissolution, leading to more pronounced unfavorable side reactions and lower Coulombic efficiency. Rdiffusion rather than interfacial resistance affected the reversibility of the Li metal anode. Enhancing the Li ion mass transport ability of electrolytes is important for achieving highly reversible charge-discharge performance of Li metal anodes at high current densities.

Kawakami, H; Nagatake, K; Ni, SJ; Nakamura, F; Takano, T; Murakami, K; Ohara, I; Isano, Y; Matsuda, … Show more authors

ADVANCED MATERIALS TECHNOLOGIES 9 ( 17 ) 2024.6 [Reviewed]

Liquid Metal Electrode Ink for Printable Lithium-Ion Batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ozawa, Y; Nishitai, Y; Ochirkhuyag, N; Usami, N; Kanto, M; Ueno, K; Ota, H

ADVANCED ENGINEERING MATERIALS 26 ( 11 ) 2024.6 [Reviewed]

Evolving better solvate electrolytes for lithium secondary batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Philippi, F; Middendorf, M; Shigenobu, K; Matsuyama, Y; Palumbo, O; Pugh, D; Sudoh, T; Dokko, K; Wa … Show more authors

CHEMICAL SCIENCE 15 ( 19 ) 7342 - 7358 2024.5 [Reviewed]

Linear ether-based highly concentrated electrolytes for Li-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ishikawa, T; Haga, S; Shigenobu, K; Sudoh, T; Tsuzuki, S; Shinoda, W; Dokko, K; Watanabe, M; Ueno, K

FARADAY DISCUSSIONS 253 ( 0 ) 385 - 406 2024.3 [Reviewed]

Solid–electrolyte interphase formation during Li metal deposition in LiN(SO2F)2-based solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ryoichi Tatara, Kohei Ikeda, Kazuhide Ueno, Masayoshi Watanabe, Kaoru Dokko

Journal of Solid State Electrochemistry 28 ( 12 ) 4483 - 4489 2024.2 [Reviewed]

Enhancing Li–S Battery Performance with Limiting Li[N(SO2F)2] Content in a Sulfolane-Based Sparingly Solvating Electrolyte

Language：English Publishing type：Research paper (scientific journal) Single Work

Jiali Liu, Shanglin Li, Nao Nomura, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

ACS Applied Materials & Interfaces 16 ( 7 ) 8570 - 8579 2024.2 [Reviewed]

DOI Web of Science PubMed Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Single Work

Enhancing Li–S Battery Performance with Limiting Li[N(SO2F)2] Content in a Sulfolane-Based Sparingly Solvating Electrolyte

Liu Jiali, Li Shanglin, Nomura Nao, Ueno Kazuhide, Dokko Kaoru, Watanabe Masayoshi

ACS Applied Materials & Interfaces 16 ( 7 ) 8570 - 8579 2024.2

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work

By enhancing the stability of the lithium metal anode and mitigating the formation of lithium dendrites through electrolyte design, it becomes feasible to extend the lifespan of lithium–sulfur (Li–S) batteries. One widely accepted approach involves the utilization of Li[N(SO2F)2] (Li[FSA]), which holds promise in stabilizing the lithium anode by facilitating the formation of an inorganic-dominant solid electrolyte interface (SEI) film. However, the use of Li[FSA] encounters limitations due to inevitable side reactions between lithium polysulfides (LiPSs) and [FSA] anions. In this study, our focus lies in precisely controlling the composition of the SEI film and the morphology of the deposited lithium, as these two critical factors profoundly influence lithium reversibility. Specifically, by subjecting an initial charging process to an elevated temperature, we have achieved a significant enhancement in lithium reversibility. This improvement is accomplished through the employment of a LiPS sparingly solvating electrolyte with a restricted Li[FSA] content. Notably, these optimized conditions have resulted in an enhanced cycling performance in practical Li–S pouch cells. Our findings underscore the potential for improving the cycling performance of Li–S batteries, even when confronted with challenging constraints in electrolyte design.

Influence of Primary Particle Morphology and Hydrophilicity of Carbon Matrix on Electrode Coating Quality and Performance of Practical High-Energy-Density Li–S Batteries

Shanglin Li, Zhaoyue Chen, Kentaro Yamamoto, Toshiki Watanabe, Yoshiharu Uchimoto, Yuki Mori, Gen I … Show more authors

Advanced Materials Interfaces 11 ( 7 ) 2024.1 [Reviewed]

PRESSURE SENSOR BASED ON AN ORGANIC ELECTROCHEMICAL TRANSISTOR WITH MODULATION OF ELECTRICAL-DOUBLE-LAYER

Language：English Publishing type：Research paper (scientific journal) Single Work

Inoue, K; Miwa, K; Shimizu, S; Ueno, K; Ohe, J; Ono, S; Ota, H

2024 IEEE 37TH INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, MEMS 604 - 605 2024

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Ion valence-gated photochromism of an aza-crowned diarylethene

Ayaka Takeguchi, Azusa Kikuchi, Kazuhide Ueno, Shinji Ishihara, Aki Nitta, Tetsuya Nakagawa, Takash … Show more authors

Photochemical & Photobiological Sciences 23 133 - 151 2023.12 [Reviewed]

Molecular Level Origin of Ion Dynamics in Highly Concentrated Electrolytes

Language：English Publishing type：Research paper (scientific journal) Single Work

Keisuke Shigenobu, Seiji Tsuzuki, Seiji Tsuzuki, Frederik Philippi, Taku Sudoh, Yosuke Ugata, Kaoru … Show more authors

The Journal of Physical Chemistry B 127 ( 48 ) 10422 - 10433 2023.11 [Reviewed]

DOI Web of Science PubMed CiNii Research Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Single Work

Single-ion conducting liquid electrolytes are key to achieving rapid charge/discharge in Li secondary batteries. The Li+ transference (or transport) numbers are the defining properties of such electrolytes and have been discussed in the framework of concentrated solution theories. However, the connection between macroscopic transference and microscopic ion dynamics remains unclear. Molecular dynamics simulations were performed to obtain direct information regarding the microscopic behaviors in highly concentrated electrolytes, and the relationships between these behaviors and the transference number were determined under anion-blocking conditions. Various solvents with different donor numbers (DNs) were used along with a Li salt of the weakly Lewis basic bis(fluorosulfonyl)amide anion for electrolyte preparation. Favorable ordered Li+ structuring and a continuous Li+ conduction pathway were observed for the fluoroethylene carbonate-based electrolyte due to its low DN. The properties were less pronounced at higher DNs, e.g., for the dimethyl sulfoxide-based electrolyte. The τLi–solventlife/τdipolerelax ratio was introduced as a factor for ion dynamics, and the two mechanisms of ion transport were considered an exchange mechanism (τLi–solventlife/τdipolerelax < 1) and a vehicle mechanism (translational motion of solvated Li+) (τLi–solventlife/τdipolerelax ≥ 1). Vehicle-type transport was dominant with high DNs, while exchangeable transport was preferable at lower DNs. These findings should aid the further selection of solvents and Li salts to prepare single-ion conducting electrolytes.

High-concentration LiPF6/sulfone electrolytes: structure, transport properties, and battery application

25 ( 43 ) 29566 - 29575 2023.11

DOI Web of Science PubMed CiNii Research Repository

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Non-flammable and oxidatively stable sulfones are promising electrolyte solvents for thermally stable high-voltage Li batteries. In addition, sulfolane-based high-concentration electrolytes (HCEs) show high Li+ ion transference numbers. However, LiPF6 has not yet been investigated as the main salt in sulfone-based HCEs for Li batteries. In this study, we investigated the phase behaviors, solvate structures, and transport properties of binary and ternary mixtures of LiPF6 and the following sulfone solvents: sulfolane (SL), dimethyl sulfone (DMS), ethyl methyl sulfone (EMS), and 3-methyl sulfolane (MSL). The stable crystalline solvates Li(SL)4PF6 and Li(DMS)2.5PF6 with high melting points were formed in the LiPF6/SL and LiPF6/DMS mixtures, respectively. In contrast, LiPF6/EMS, LiPF6/MSL, and LiPF6/SL/another sulfone mixtures remained liquids over a wide temperature range. Raman spectroscopy revealed that SL and another sulfone are competitively coordinated to Li+ ions to dissociate LiPF6 in the ternary mixtures. Although the ionic conductivity decreased with increasing LiPF6 concentration due to an increase in viscosity, Li+ ions diffused faster than PF6−via exchanging ligands in the HCE [LiPF6]/[SL]/[DMS] = 1/2/2, resulting in a higher Li ion transference number than that in conventional Li battery electrolytes.

Tetra-arm poly(ethylene glycol) gels with highly concentrated sulfolane-based electrolytes exhibiting high Li-ion transference numbers

Tasaki Natsumi, Ugata Yosuke, Hashimoto Kei, Kokubo Hisashi, Ueno Kazuhide, Watanabe Masayoshi, Dok … Show more authors

PHYSICAL CHEMISTRY CHEMICAL PHYSICS 25 ( 27 ) 17793 - 17797 2023.7 [Reviewed]

Molecular Dynamics Simulations of High-Concentration Li[TFSA] Sulfone Solution: Effect of Easy Conformation Change of Sulfolane on Fast Diffusion of Li Ion

Language：English Publishing type：Research paper (scientific journal) Joint Work

Tsuzuki Seiji, Ikeda Shuhei, Shinoda Wataru, Shigenobu Keisuke, Ueno Kazuhide, Dokko Kaoru, Watanab … Show more authors

JOURNAL OF PHYSICAL CHEMISTRY B 127 ( 28 ) 6333 - 6341 2023.7 [Reviewed]

DOI Web of Science PubMed CiNii Research Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

The parameters of the polarizable force filed used for molecular dynamics simulations of Li diffusion in high-concentration lithium bis(trifluoromethanesulfonyl)amide (Li[TFSA]) sulfone (sulfolane, dimethylsulfone, ethylmethylsulfone and ethyl-ipropylsulfone) solutions were refined. The densities of the solutions obtained by molecular dynamics simulations reproduced well the experimental values. The calculated concentration, temperature and solvent dependencies of self-diffusion coefficients of ions and solvents in the mixtures well reproduce the experimentally observed dependencies. Ab initio calculations show that the intermolecular interactions between Li ion and four sulfones are not largely different. Conformational analyses show that sulfolane can change the conformation more easily owing to lower barrier height for pseudorotation compared to the rotational barrier heights of diethylsulfone and ethylmethylsulfone. Molecular dynamics simulations indicate that the easy conformation change of solvent affects the rotational relaxation of the solvent and the diffusion of Li ion in the mixture. The easy conformation change of sulfolane is one of the causes of faster diffusion of Li ion in the mixture of Li[TFSA] and sulfolane compared to the mixtures of smaller dimethylsulfone and ethylmethylsulfone.

Lithium-Ion Dynamics in Sulfolane-Based Highly Concentrated Electrolytes

Ikeda Shuhei, Tsuzuki Seiji, Sudoh Taku, Shigenobu Keisuke, Ueno Kazuhide, Dokko Kaoru, Watanabe Ma … Show more authors

JOURNAL OF PHYSICAL CHEMISTRY C 127 ( 28 ) 13837 - 13845 2023.7 [Reviewed]

Tetra-arm poly(ethylene glycol) gels with highly concentrated sulfolane-based electrolytes exhibiting high Li-ion transference numbers†

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Joint Work

Tasaki Natsumi, Ugata Yosuke, Hashimoto Kei, Kokubo Hisashi, Ueno Kazuhide, Watanabe Masayoshi, Dok … Show more authors

The Journal of physical chemistry. C 25 ( 27 ) 17793 - 17797 2023.6

Li-Ion Transport and Solution Structure in Sulfolane-Based Localized High-Concentration Electrolytes

Language：English Publishing type：Research paper (scientific journal) Publisher：The Royal Society of Chemistry Joint Work

We demonstrate that tetra-arm poly(ethylene glycol) gels containing highly concentrated sulfolane-based electrolytes exhibit high Li+ transference numbers. The low polymer concentration and homogeneous polymer network in the gel electrolyte are useful in achieving both mechanical reliability and high Li+ transport ability.

Sudoh Taku, Ikeda Shuhei, Shigenobu Keisuke, Tsuzuki Seiji, Dokko Kaoru, Watanabe Masayoshi, Shinod … Show more authors

JOURNAL OF PHYSICAL CHEMISTRY C 127 ( 25 ) 12295 - 12303 2023.6 [Reviewed]

Imidazolium-Functionalized Anthraquinone for High-Capacity Electrochemical CO2 Capture

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work

Iida Hiroki, Kondou Shinji, Tsuzuki Seiji, Tashiro Mao, Shida Naoki, Motokura Ken, Dokko Kaoru, Wat … Show more authors

JOURNAL OF PHYSICAL CHEMISTRY C 127 ( 21 ) 10077 - 10086 2023.5 [Reviewed]

Imidazolium-Functionalized Anthraquinone for High-Capacity Electrochemical CO2 Capture

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work

Kondou Shinji, Tsuzuki Seiji, Tashiro Mao, Motokura Ken, Shida Naoki, Iida Hiroki, Ueno Kazuhide, W … Show more authors

The Journal of Physical Chemistry C 127 ( 21 ) 2023.5

Lithium Aluminate Nanoflakes as an Additive to Sulfur Cathodes for Enhanced Mass Transport in High-Energy-Density Lithium-Sulfur Pouch Cells Utilizing Sparingly Solvating Electrolytes

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS) Joint Work

Electrochemical separation methods utilizing quinones as CO2 capture agents have gained considerable interest owing to their low-energy requirements for near-isothermal CO2 separation. However, the low solubility of quinones in nonaqueous solvents limits their total CO2 carrying capacity in the system. In this study, we synthesized an ionically modified anthraquinone, 1-butyl-3-((2′-anthraquinoyl)methyl)imidazolium bis(trifluoromethanesulfonyl)amide ([BAQMIM][TFSA]), which exhibited a 360-fold increase in solubility compared to pristine anthraquinone in dimethyl sulfoxide. The synthesized ionic quinone derivative can also serve as a supporting electrolyte, offering both high ionic conductivity (12.2 mS cm–1) and quinone concentration (200 mM). Constant-potential electrolysis demonstrated a high CO2 carrying capacity in a highly concentrated [BAQMIM][TFSA] solution. The predominantly reversible CO2 capture and subsequent release processes were successfully monitored through in situ spectroscopic analysis and density functional theory calculations. These findings provide a promising approach toward large-scale volumetric CO2 separation through the functionalization of quinones.

Ghosh Arnab, Liu Jiali, Li Shanglin, Ueno Kazuhide, Dokko Kaoru, Watanabe Masayoshi

ACS APPLIED MATERIALS & INTERFACES 15 ( 19 ) 23104 - 23114 2023.5 [Reviewed]

Self-assembling bilayer wiring with highly conductive liquid metal and insulative ion gel layers

Language：English Publishing type：Research paper (scientific journal) Joint Work

Murakami Koki, Isano Yuji, Asada Juri, Usami Natsuka, Isoda Yutaka, Takano Tamami, Matsuda Ryosuke, … Show more authors

SCIENTIFIC REPORTS 13 ( 1 ) 2023.4 [Reviewed]

Distinct Differences in Li-Deposition/Dissolution Reversibility in Sulfolane-Based Electrolytes Depending on Li-Salt Species and Their Solvation Structures

Language：English Publishing type：Research paper (scientific journal) Joint Work

Liu Jiali, Kaneko Tomoaki, Ock Ji-young, Kondou Shinji, Ueno Kazuhide, Dokko Kaoru, Sodeyama Keitar … Show more authors

JOURNAL OF PHYSICAL CHEMISTRY C 127 ( 12 ) 5689 - 5701 2023.3 [Reviewed]

Phase Behaviors and Ion Transport Properties of LiN(SO2CF3)2/Sulfone Binary Mixtures

Language：English Publishing type：Research paper (scientific journal) Joint Work

TATARA Ryoichi, UGATA Yosuke, MIYAZAKI Shuhei, KISHIDA Natsuki, SASAGAWA Shohei, UENO Kazuhide, TSU … Show more authors

Electrochemistry 91 ( 3 ) 037008 - 037008 2023.3 [Reviewed]

Anionic Effects on Li-Ion Activity and Li-Ion Intercalation Reaction Kinetics in Highly Concentrated Li Salt/Propylene Carbonate Solutions

Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人　電気化学会 Joint Work

Highly concentrated Li salt/aprotic solvent solutions are promising electrolytes for next-generation batteries. Understanding the Li+ ion transport process is crucial for designing novel battery electrolytes. In this study, we systematically investigated the phase behavior, solvate structures, and Li+ transport properties of binary mixtures comprising lithium bis(trifluoromethanesulfonyl)amide (LiTFSA) and various sulfones, such as sulfolane (SL), 3-methyl sulfolane (MSL), dimethyl sulfone (DMS), ethyl methyl sulfone (EMS), and ethyl isopropyl sulfone (EiPS). Except for the MSL system, the [LiTFSA]/[sulfone] = 1/2 mixtures remained in a liquid state at room temperature, thus enabling a systematic comparison of the Li+ transport properties in the highly concentrated electrolytes. In highly concentrated liquid electrolytes, Li+ ions diffuse by exchanging ligands (sulfone and TFSA). Li+ ions diffuse faster than TFSA in all electrolytes except the EiPS-based electrolyte at a composition of [LiTFSA]/[sulfone] = 1/2, resulting in high Li+ transference numbers. SL-based electrolytes show higher ionic conductivity and Li+ transference numbers than other sulfone-based electrolytes. Consequently, sulfone solvents with compact molecular sizes and low energy barriers of conformational change are favorable for enhancing the Li+ ion transport in the electrolytes.

Ugata, Y; Tatara, R; Ock, JY; Zhang, JJ; Ueno, K; Watanabe, M; Dokko, K

JOURNAL OF PHYSICAL CHEMISTRY C 127 ( 8 ) 3977 - 3987 2023.3

Concentrated Nonaqueous Polyelectrolyte Solutions: High Na-Ion Transference Number and Surface-Tethered Polyanion Layer for Sodium-Metal Batteries

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Shinji Kondou, Yusuke Sakashita, Asuka Morinaga, Yu Katayama Yu Katayama, Kaoru Dokko, Masayoshi Wa … Show more authors

ACS APPLIED MATERIALS & INTERFACES 15 ( 9 ) 11741 - 11755 2023.2 [Reviewed]

Ion Transport in Glyme- and Sulfolane-Based Highly Concentrated Electrolytes

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Single Work

Keisuke Shigenobu, Taku Sudoh, Junichi Murai, Kaoru Dokko, Masayoshi Watanabe, Kazuhide Ueno

THE CHEMICAL RECORD 23 ( 8 ) 2023.2 [Reviewed]

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Single Work

Highly stretchable and sensitive silicone composites with positive piezoconductivity using nickel powder and ionic liquid

R. Matsuda, Y. Isano, K. Ueno, and H. Ota

APL Bioengineering 7 ( 1 ) 2023.2 [Reviewed]

On the concentration polarisation in molten Li salts and borate-based Li ionic liquids

Language：English Publishing type：Research paper (scientific journal) Single Work

Keisuke Shigenobu, Frederik Philippi, Seiji Tsuzuki, Hisashi Kokubo, Kaoru Dokko, Masayoshi Watanab … Show more authors

Physical Chemistry Chemical Physics 25 ( 9 ) 6970 - 6978 2023.1 [Reviewed]

DOI Web of Science PubMed CiNii Research

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Single Work

Electrolytes that transport only Li ions play a crucial role in improving rapid charge and discharge properties in Li secondary batteries. Single Li-ion conduction can be achieved via liquid materials such as Li ionic liquids containing Li+ as the only cations because solvent-free fused Li salts do not polarise in electrochemical cells, owing to the absence of neutral solvents that allow polarisation in the salt concentration and the inevitably homogeneous density in the cells under anion-blocking conditions. However, we found that borate-based Li ionic liquids induce concentration polarisation in a Li/Li symmetric cell, which results in their transference (transport) numbers under anion-blocking conditions (tabc Li) being well below unity. The electrochemical polarisation of the borate-based Li ionic liquids was attributed to an equilibrium shift caused by exchangeable B-O coordination bonds in the anions to generate Li salts and borate-ester solvents at the electrode/electrolyte interface. By comparing borate-based Li ionic liquids containing different ligands, the B-O bond strength and extent of ligand exchange were found to be directly linked to the tabc Li values. This study confirms that the presence of dynamic exchangeable bonds causes electrochemical polarisation and provides a reference for the rational molecular design of Li ionic liquids aimed at achieving single-ion conducting liquid electrolytes.

Enhancing the reversibility of Li deposition/dissolution in sulfur batteries using high-concentration electrolytes to develop anode-less batteries with lithium sulfide cathode

Hikari Asano, Jiali Liu, Kazuhide Ueno, Kaoru Dokko, Toshikatsu Kojima, Nobuhiko Takeichi, Takuhiro … Show more authors

Journal of Power Sources 554 ( 15 ) 2023.1 [Reviewed]

Does Li-ion transport occur rapidly in localized high-concentration electrolytes?

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Single Work

Yoshifumi Watanabe, Yosuke Ugata, Kazuhide Ueno, Masayoshi Watanabe and Kaoru Dokko

Physical Chemistry Chemical Physics 25 ( 4 ) 3092 - 3099 2022.12 [Reviewed]

DOI Web of Science PubMed Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Single Work

Transparent and Breathable Ion Gel-Based Sensors toward Multimodal Sensing Ability

Yuji Isano, Hajime Fujita, Koki Murakami, Sijie Ni, Yuta Kurotaki, Tamami Takano, Yutaka Isoda, Ryo … Show more authors

ADVANCED MATERIALS TECHNOLOGIES 7 ( 11 ) 2022.11 [Reviewed]

Enhancing the reversibility of Li deposition/dissolution in sulfur batteries using high-concentration electrolytes to develop anode-less batteries with lithium sulfide cathode

Language：English Publishing type：Research paper (scientific journal) Single Work

Asano Hikari, Miyuki Takuhiro, Yamakawa Yukio, Watanabe Masayoshi, Dokko Kaoru, Liu Jiali, Ueno Kaz … Show more authors

Journal of Power Sources 554 2022.11

Temperature Dependency of Ion Transport in Highly Concentrated Li Salt/Sulfolane Electrolyte Solutions

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Joint Work

The reversibility of Li deposition/dissolution onto/from a copper substrate is analyzed herein for fabricating anodeless Li2S-cathode-based batteries using sulfolane (SL)-based sparingly solvating electrolytes to prevent lithium-polysulfide dissolution. The composition of electrolytes-binary lithium bis(trifluoromethanesulfonyl) amide/lithium bis(fluorosulfonyl)amide (LiTFSA/LiFSA; 9:1 molar ratio) in SL solvent-considerably affects the reversibility; a high-concentration electrolyte (HCE) and a localized high-concentration electrolyte (LHCE: HCE diluted by non-coordinating hydrofluoroether) exhibit superior reversibility than that of 1 M solution. Solid electrolyte interphases (SEI) with high F compositions and relatively low O concentrations are formed on the HCE-and LHCE-deposited Li surfaces. SEI formation via FSA decomposition is promoted in the HCE and LHCE, whereas SL decomposition is prohibited by the fluorine-rich SEI. The Li-deposit morphology is significantly affected by the nucleation overpotential at the initial deposition, which is influenced by the nature of the formed SEIs. Small-surface-area deposits with a low nucleation overpotential suppress the electrolyte decomposition and the formation of dead Li, resulting in high reversibility. Optimal reversibility is achieved by performing low -current-density initial deposition at 60 degrees C with the LHCE. The charge/discharge characteristics of anode-less Cu||Li2S batteries are determined under the reversibility-optimized conditions; 75 charge/discharge cycles and a 50-cycle capacity retention rate of 47.5% are achieved.

Yosuke Ugata, Gen Hasegawa, Naoaki Kuwata, Kazuhide Ueno, Masayoshi Watanabe, and Kaoru Dokko

THE JOURNAL OF PHYSICAL CHEMISTRY C 126 ( 45 ) 19084 - 19090 2022.11 [Reviewed]

Does Li-ion transport occur rapidly in localized high-concentration electrolytes?†

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Single Work

Watanabe Yoshifumi, Ugata Yosuke, Ueno Kazuhide, Masayoshi Watanabe, Kaoru Dokko

Physical Chemistry Chemical Physics 25 ( 4 ) 3092 - 3099 2022.11

Concentrated Lithium Dodecyl Sulfate Aqueous Electrolytes: Utilizing Self-Assembly and Interfacial Adsorption for Aqueous Li-ion Batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Joint Work

The ionic conductivity and lithium-ion transference number of electrolytes significantly influence the rate capability of Li-ion batteries. Highly concentrated Li-salt/sulfolane (SL) electrolytes exhibit elevated Li+ transference numbers due to lithium-ion hopping via a ligand exchange mechanism within their –Li+–SL–Li+– network. However, highly concentrated electrolytes (HCEs) are extremely viscous and have an ionic conductivity that is one order of magnitude less than that of conventional electrolytes. Dilution of HCEs with a non-coordinating hydrofluoroether (HFE) lowers the viscosity and produces localized high-concentration electrolytes (LHCE). However, the mechanism of Li+ transport in LHCEs is unclear. This study investigated the transport properties of LHCEs prepared by diluting a SL-based HCE with 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether. Electrolyte viscosity decreases dramatically upon dilution, whereas ionic conductivity increases only slightly. Ion diffusivity increases with increasing HFE content due to the decrease in electrolyte viscosity. However, the Li+ transference number declines, because the HFE interferes with conduction via the Li+ hopping mechanism. The resulting decrease in the product of ionic conductivity and Li+ transference number indicates superior lithium-ion transport in the parent HCE compared with LHCEs.

9 ( 20 ) e202200870 2022.10 [Reviewed]

Carbonaceous-Material-Induced Gelation of Concentrated Electrolyte Solutions for Application in Lithium–Sulfur Battery Cathodes

Language：English Publishing type：Research paper (scientific journal) Single Work

Ryo Motoyoshi, Shanglin Li, Seiji Tsuzuki, Arnab Ghosh, Kazuhide Ueno, Kaoru Dokko, and Masayoshi W … Show more authors

ACS APPLIED MATERIALS & INTERFACES 14 ( 40 ) 45403 - 45413 2022.9 [Reviewed]

Stretchable Gas Barrier Films Using Liquid Metal toward a Highly Deformable Battery

Language：English Publishing type：Research paper (scientific journal) Single Work

Nyamjargal Ochirkhuyag, Yuuki Nishitai, Satoru Mizuguchi, Yuji Isano, Sijie Ni, Koki Murakami, Masa … Show more authors

ACS APPLIED MATERIALS & INTERFACES 14 ( 42 ) 48123 - 48132 2022.9 [Reviewed]

Eutectic Electrolytes Composed of LiN(SO2F)2 and Sulfones for Li-Ion Batteries

Language：English Publishing type：Research paper (scientific journal) Single Work

Ueno Kazuhide, Nagamine Masayuki, Masayoshi Watanabe, Chen Yichuan, Sasagawa Shohei, Mita Hiroki, S … Show more authors

Journal of physical chemistry. C 126 ( 24 ) 10024 - 10034 2022.7

Transparent and Breathable Temperature/Humidity Sensor using Ion Gel and Elastomer Nanosheet

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Sulfones are polar molecules that can be used as thermally stable electrolyte solvents for Li-ion batteries (LIBs). Li salts form stoichiometric solvates with sulfones in the electrolytes. The melting points of the solvates tend to be higher than room temperature, thereby limiting the operating temperature range of the batteries. In this study, the applicability of ternary eutectic mixtures of LiN(SO2F)2 (LiFSA), sulfolane (SL), and dimethyl sulfone (DMS) as LIB electrolytes was assessed. Relative to the binary LiFSA–sulfone electrolytes, the ternary eutectic electrolytes remained liquid over a wide temperature range due to the increased entropy of mixing. Sulfone-bridged Li+–sulfone–Li+ and anion-bridged Li+–FSA––Li+ network structures were formed in the eutectic electrolyte with a composition of [LiFSA]/[SL]/[DMS] = 1/1.5/1.5. Pulsed-field gradient NMR measurements revealed that the Li+ ion dynamically exchanges sulfones and anions and diffuses more rapidly than these ligands, resulting in the relatively high Li+ transference number of the electrolyte. Highly reversible charge–discharge processes of the LiCoO2 and graphite electrodes were attained using the ternary eutectic electrolyte. The rate capability of the Li/LiCoO2 cell in the eutectic electrolyte was comparable to that of the cell in the conventional 1 M LiPF6 in an ethylene carbonate/dimethyl carbonate solution despite its lower ionic conductivity.

Isano Yuji, Fujita Hajime, Ueno Kazuhide, Fujie Toshinori, Ota Hiroki

IEEJ Transactions on Sensors and Micromachines 142 ( 7 ) 168 - 169 2022.7 [Reviewed]

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Institute of Electrical Engineers of Japan Joint Work

Transparent and Breathable Ion Gel-Based Sensors toward Multimodal Sensing Ability

Yuji Isano, Hajime Fujita, Koki Murakami, Sijie Ni, Yuta Kurotaki, Tamami Takano, Yutaka Isoda, Ryo … Show more authors

Advanced Materials Technologies 2022.6 [Reviewed]

Electrochemical Pretreatment of Solid-Electrolyte Interphase Formation for Enhanced Li4Ti5O12 Anode Performance in a Molten Li-Ca Binary Salt Hydrate Electrolyte

Language：English Publishing type：Research paper (scientific journal) Single Work

Kondou, S; Watanabe, Y; Dokko, K; Watanabe, M; Ueno, K

CHEMELECTROCHEM 9 ( 11 ) 2022.6

Eutectic Electrolytes Composed of LiN(SO2F)2 and Sulfones for Li-Ion Batteries

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Yosuke Ugata, Yichuan Chen, Shohei Sasagawa, Kazuhide Ueno, Masayoshi Watanabe, Hiroki Mita, Jusuke … Show more authors

The Journal of Physical Chemistry C 126 ( 24 ) 10024 - 10034 2022.6 [Reviewed]

Li+ transference number and dynamic ion correlations in glyme-Li salt solvate ionic liquids diluted with molecular solvents

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Single Work

24 ( 23 ) 14269 - 14276 2022.5 [Reviewed]

DOI Web of Science PubMed CiNii Research

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Single Work

LiNi0.5Mn1.5O4-Hybridized Gel Polymer Cathode and Gel Polymer Electrolyte Containing a Sulfolane-Based Highly Concentrated Electrolyte for the Fabrication of a 5 V Class of Flexible Lithium Batteries

Binshen Wang , Jiali Liu, Ji-young Ock, Ryo Motoyoshi, Shanglin Li, Kazuhide Ueno, Kaoru Dokko, Sei … Show more authors

ACS Omega 7 ( 21 ) 17732 - 17740 2022.5 [Reviewed]

Li-Ion Transport and Solvation of a Li Salt of Weakly Coordinating Polyanions in Ethylene Carbonate/Dimethyl Carbonate Mixtures

Language：English Publishing type：Research paper (scientific journal) Single Work

Shinji Kondou, Yusuke Sakashita, Xiaoxiao Yang, Kei Hashimoto, Kaoru Dokko, Masayoshi Watanabe, Kaz … Show more authors

ACS Applied Materials & Interfaces 14 ( 16 ) 18324 - 18334 2022.4 [Reviewed]

DOI Web of Science PubMed CiNii Research

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Single Work

Electrolytes with a high Li-ion transference number (t(Li)) have attracted significant attention for the improvement of the rapid charge-discharge performance of Li-ion batteries (LIBs). Nonaqueous polyelectrolyte solutions exhibit high t(Li) upon immobilization of the anion on a polymer backbone. However, the transport properties and Li-ion solvation in these media are not fully understood. Here, we investigated the Li salt of a weakly coordinating polyanion, poly[(4-styrenesulfonyl)-(trifluoromethanesulfonyl)amide] (poly(LiSTFSA)), in various ethylene carbonate and dimethyl carbonate mixtures. The highest ionic conductivity was unexpectedly observed for the lowest polar mixture at the highest salt concentration despite the low dissociation degree of poly(LiSTFSA). This was attributed to a unique conduction phenomenon resulting from the faster diffusion of transiently solvated Li ions along the interconnected aggregates of polyanion chains. A Li/LiFePO4 cell using such an electrolyte demonstrated improved rate capability. These results provide insights into a design strategy of nonaqueous liquid electrolytes for LIBs.

Electrochemical Pretreatment of Solid-Electrolyte Interphase Formation for Enhanced Li4Ti5O12 Anode Performance in a Molten Li-Ca Binary Salt Hydrate Electrolyte

9 ( 11 ) e202200061 2022.3 [Reviewed]

Importance of Mass Transport in High Energy Density Lithium‐Sulfur Batteries Under Lean Electrolyte Conditions

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Single Work

Shanglin Li,Shota Ishikawa, Jiali Liu, Kazuhide Ueno, Kaoru Dokko, Gen Inoue, Masayoshi Watanabe

Batteries & Supercaps 5 ( 5 ) 2022.3 [Reviewed]

Effects of polyimide sequence and monomer structures on CO2 permeation and mechanical properties of sulfonated polyimide/ionic liquid composite membranes

Language：English Publishing type：Research paper (scientific journal) Joint Work

ShogoTachibana, Kei Hashimoto, Haruna Mizuno, Kazuhide Ueno, Masayoshi Watanabe

Polymer 241 124533 2022.2 [Reviewed]

Local Lithium-Ion Transport of a Ternary Sulfolane-Lithium Bis(trifluoromethanesulfonyl)amide-Carbonate Electrolyte: Experimental and First-Principles Molecular Dynamics Analysis toward Quasi-Solid-State Lithium-Ion Battery

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Science Ltd. Joint Work

Jun Kawaji, Atsushi Unemoto, Eiji Seki, Motoyuki Hirooka, Tamio Ikeshoji, Kazuhide Ueno, Kaoru Dokk … Show more authors

Journal of The Electrochemical Society 169 ( 2 ) 020534 2022.2 [Reviewed]

Direct Wiring of Liquid Metal on an Ultrasoft Substrate Using a Polyvinyl Alcohol Lift-off Method

Language：English Publishing type：Research paper (scientific journal) Joint Work

Koki Murakami, Ryota Tochinai, Daiki Tachibana, Yuji Isano, Ryosuke Matsuda, Fumika Nakamura, Yuta … Show more authors

ACS Applied Materials & Interfaces 14 ( 5 ) 7241 - 7251 2022.1 [Reviewed]

Effects of polyimide sequence and monomer structures on CO2 permeation and mechanical properties of sulfonated polyimide/ionic liquid composite membranes

Language：English Publishing type：Research paper (scientific journal) Single Work

Watanabe Masayoshi, Ueno Kazuhide, Hashimoto Kei, Mizuno Haruna, Tachibana Shogo

POLYMER 241 2022.1

Ultrafast and Highly Deformable Electromagnetic Hydrogel Actuators Assembled from Liquid Metal Gel Fiber

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Science Ltd. Joint Work

The effects of polymer structure on CO2 separation and mechanical properties of ion gel membranes composed of ionic liquids (ILs) and sulfonated polyimides (SPIs) were investigated. SPIs with different sequential distributions of ionic groups (multiblock and random) were synthesized. The multiblock copolymer exhibited higher IL uptake (similar to 80 wt.%) than the random copolymer, resulting in higher CO2 permeability (similar to 480 Barrer). The multiblock copolymer exhibited a clearer phase-separated structure than the random copolymer. However, the strain at the break of the multiblock copolymer was lower owing to the brittleness of the non-ionic phase. To improve the mechanical properties, an SPI containing fluorinated groups as a non-ionic part was also synthesized. Compared with the random SPI ion gel membranes, the multiblock SPI ion gel membranes containing fluorinated groups exhibited good CO2 permeability (similar to 500 Barrer) and simultaneously ductile properties with higher strain at the break due to the plasticization of the non-ionic phase, enabling a thin and tough membrane with excellent CO2 separation properties. These results indicate that the polyimide sequence in addition to the chemical structure of monomers affects CO2 permeation and mechanical properties of the sulfonated polyimide/ionic liquid composite membranes.

Daiki Tachibana, Koki Murakami, Takashi Kozaki, Ryosuke Matsuda, Yutaka Isoda, Fumika Nakamura, Yuj … Show more authors

Advanced Intelligent Systems 4 ( 5 ) 2100212-1 - 2100212-11 2022.1 [Reviewed]

Language：English Publishing type：Research paper (scientific journal) Joint Work

透明・高通気性イオンゲル超薄膜温湿度センサの開発

伊佐野雄司, 藤田創, 村上航輝, 倪思捷, 黒瀧悠太, 高野珠実, 磯田豊, 松田涼佑, 中村史香, 西躰優希, 井上航太, 川上寛樹, 大久保佑亮, 上野和英, 藤枝 … Show more authors

生体医工学 Annual60 ( Abstract ) 210_1 - 210_1 2022

Transparent, Breathable Temperature and Humidity Sensor using Ion Gel and Polymer Thin Films

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：公益社団法人日本生体医工学会 Joint Work

次世代のウェアラブルデバイスとして，柔軟性，透明性，気体透過性といった，既存の硬質デバイスでは実現できない特性を持ったデバイスが注目されている．これらのデバイスに用いられるセンサとして，ポリマー薄膜とナノマテリアルを用いた薄膜センサが数多く開発されている．しかし，こうしたセンサに用いられるナノ材料は測定対象の選択性が低く，対象の拡張も難しいという欠点を抱えている．こうした課題を解決できる新たなセンシング材料として，イオン液体が注目されている．イオン液体は常温で液体の塩であり，アニオンとカチオンの組み合わせによって様々な特性を示す．そこで，本研究では親水性の異なる2種のイオン液体とポリマーを組み合わせたイオンゲルをセンシング材料として用いて，透明・高通気性で温湿度の選択的検出が可能な薄膜センサを開発した．センサは生体適合性の高いポリジメチルシロキサン薄膜上に，スプレーコーティングを用いてカーボンナノチューブ電極とイオンゲル感温・感湿部を塗布することで作製した．センサは可視光域で80 %以上の光透過率および人体の経皮水分損失の2.8倍の水蒸気透過量を示した．また，温度と湿度に反応する親水性イオンゲル湿度センサの出力値を温度のみに反応する疎水性イオンゲル温度センサによって校正することで温度と湿度の選択的検出を実現した．今後は，イオン液体とポリマーの変更による薄膜センサの多機能化が期待される．

Isano Yuji, Fujita Hajime, Murakami Koki, Ni Sijie, Kurotaki Yuta, Takano Tamami, Isoda Yutaka, Mat … Show more authors

The Proceedings of Mechanical Engineering Congress, Japan 2022 ( 0 ) J221-03 2022

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society of Mechanical Engineers Joint Work

Effects of Li ion-solvent interaction on ionic transport and electrochemical properties in highly concentrated cyclic carbonate electrolytes

Keisuke Shigenobu, Taku Sudoh, Mayu Tabuchi, Seiji Tsuzuki, Wataru Shinoda, Kaoru Dokko, Masayoshi … Show more authors

Journal of Non-Crystalline Solids: X 11-12 100071 2021.12 [Reviewed]

Liquid Metal–Ionic Liquid Composite Gels for Soft, Mixed Electronic–Ionic Conductors

Language：English Publishing type：Research paper (scientific journal) Joint Work

Juri Asada, Natsuka Usami, Hiroki Ota, Masayoshi Watanabe, Kazuhide Ueno

Macromolecular Chemistry and Physics 223 ( 8 ) 2100319-1 - 2100319-8 2021.11 [Reviewed]

Design of Polymer Network and Li+ Solvation Enables Thermally and Oxidatively Stable, Mechanically Reliable, and Highly Conductive Polymer Gel Electrolyte for Lithium Batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Kei Hashimoto, Ryoichi Tatara, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Journal of The Electrochemical Society 168 ( 9 ) 2021.9 [Reviewed]

Solvate electrolytes for Li and Na batteries: structures, transport properties, and electrochemistry

Language：English Publishing type：Research paper (scientific journal) Joint Work

Yosuke Ugata, Keisuke Shigenobu, Ryoichi Tatara, Kazuhide Ueno, Masayoshi Watanabe, Kaoru Dokko

Physical chemistry chemical physics 23 ( 38 ) 21419 - 21436 2021.9 [Reviewed]

DOI Web of Science PubMed CiNii Research Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Single Work

Polar solvents dissolve Li and Na salts at high concentrations and are used as electrolyte solutions for batteries. The solvents interact strongly with the alkali metal cations to form complexes in the solution. The activity (concentration) of the uncoordinated solvent decreases as the salt concentration is increased. At extremely high salt concentrations, all the solvent molecules are involved in the coordination of the ions and form the solvates of the salts. In this article, we review the structures, transport properties, and electrochemistry of Li/Na salt solvates. In molten solvates, the activity of the uncoordinated solvent is negligible; this is the main origin of their peculiar characteristics, such as high thermal stability, wide electrochemical window, and unique ion transport. In addition, the solvent activity greatly influences the electrochemical reactions in Li/Na batteries. We highlight the attractive features of molten solvates as promising electrolytes for next-generation batteries.

Highly Concentrated NaN(SO2F)2/3-Methylsulfolane Electrolyte Solution Showing High Na-Ion Transference Number under Anion-Blocking Conditions

TATARA Ryoichi, OKAMOTO Yukihiro, UGATA Yosuke, UENO Kazuhide, WATANABE Masayoshi, DOKKO Kaoru

Electrochemistry 89 ( 6 ) 590 - 596 2021.9 [Reviewed]

Electrochemical Properties of Poly(vinylidene fluoride-co-hexafluoropropylene) Gel Electrolytes with High-Concentration Li Salt/Sulfolane for Lithium Batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人　電気化学会 Joint Work

The performance of a sodium-ion (Na) battery is significantly influenced by its electrolyte characteristics. In particular, the transport properties of the electrolyte have considerable effects on the discharge rate capability. During discharging of a Na battery at high current densities, a concentration gradient of Na salt develops because both cations and anions are mobile in the liquid electrolyte. Concentration polarization can be suppressed by increasing the Na+ transference number (tNa+) of the electrolyte. This study demonstrates that highly concentrated NaN(SO2F)2 dissolved in 3-methylsulfolane (MSL) exhibits a high tNa+ value of >0.6 under anion-blocking conditions. Raman spectroscopy revealed that Na+ ions formed complexes with MSL and anions in the electrolyte. Na+ ions exchange ligands dynamically and move faster than the ligands, resulting in a high tNa+. The high tNa+ enables a high-rate discharge of the Na battery, despite the low ionic conductivity of the highly concentrated electrolyte.

Other Link： https://ci.nii.ac.jp/naid/130008083685

89 ( 6 ) 567 - 572 2021.8 [Reviewed]

Protic Ionic Liquids Can Be Both Free Proton Conductors and Benign Superacids

Language：English Publishing type：Research paper (scientific journal) Publisher：The Electrochemical Society of Japan Joint Work

Other Link： https://ci.nii.ac.jp/naid/130008071030

Younes Ansari, Kazuhide Ueno, C. Austen Angell

The Journal of Physical Chemistry B 125 ( 28 ) 7855 - 7862 2021.7 [Reviewed]

Local Structure of Li+ in Superconcentrated Aqueous LiTFSA Solutions

Language：English Publishing type：Research paper (scientific journal) Joint Work

Hikari Watanabe, Nana Arai, Erika Nozaki, Jihae Han, Kenta Fujii, Kazutaka Ikeda, Toshiya Otomo, Ka … Show more authors

The Journal of Physical Chemistry B 125 ( 27 ) 7477 - 7484 2021.7 [Reviewed]

Rate Performance of LiCoO2 Half-cells Using Highly Concentrated Lithium Bis(fluorosulfonyl)amide Electrolytes and Their Relevance to Transport Properties

Language：English Publishing type：Research paper (scientific journal) Joint Work

89 ( 4 ) 389 - 394 2021.7 [Reviewed]

Transport Properties of Flexible Composite Electrolytes Composed of Li1.5Al0.5Ti1.5(PO4)3 and a Poly(vinylidene fluoride-co-hexafluoropropylene) Gel Containing a Highly Concentrated Li[N(SO2CF3)2]/Sulfolane Electrolyte

Language：English Publishing type：Research paper (scientific journal) Publisher：The Electrochemical Society of Japan Joint Work

Other Link： https://ci.nii.ac.jp/naid/130008062337

Ji-young Ock, Miki Fujishiro, Kazuhide Ueno, Izuru Kawamura, Ryoichi Tatara, Kei Hashimoto, Masayos … Show more authors

ACS Omega 6 ( 24 ) 16187 - 16193 2021.6 [Reviewed]

Structural Effects of Solvents on Li-Ion-Hopping Conduction in Highly Concentrated LiBF4/Sulfone Solutions

Language：English Publishing type：Research paper (scientific journal) Joint Work

125 ( 24 ) 6600 - 6608 2021.6 [Reviewed]

DOI Web of Science PubMed CiNii Research Repository

Language：English Publishing type：Research paper (scientific journal) Joint Work

Li-ion-hopping conduction is known to occur in certain highly concentrated electrolytes, and this conduction mode is effective for achieving lithium batteries with high rate capabilities. Herein, we investigated the effects of solvent structure on the hopping conduction of Li ions in highly concentrated LiBF4/sulfone electrolytes. Raman spectroscopy revealed that Li+ ion forms complexes with sulfone and anion, and contact ion pairs and ionic aggregates are formed in the highly concentrated electrolytes. Li+ exchanges ligands (sulfone and BF4 −) rapidly to produce unusual hopping conduction in highly concentrated electrolytes. The structure of the solvent significantly influences the hopping conduction process. We measured the self-diffusion coefficients of Li+ (DLi), anions (Danion), and sulfone solvents (Dsol) in electrolytes. The ratio of the self-diffusion coefficients (DLi/Dsol) tended to be higher for cyclic sulfones (sulfolane and 3-methylsulfolane) than for acyclic sulfones, which suggests that cyclic sulfone molecules facilitate Li-ion-hopping. The hopping conduction increases the Li+ transference number (tLi+ abc) under anion-blocking conditions, and tLi+ abc of [LiBF4]/[cyclic sulfone] = 1/2 is as high as 0.8.

Direct Observation of Photo-Induced Reversible Sol-Gel Transition in Block Copolymer Self-Assembly Containing an Azobenzene Ionic Liquid

Mizuno　Haruna, Hashimoto　Kei, Shigenobu　Keisuke, Kokubo　Hisashi, Ueno　Kazuhide, Watanabe　Masayoshi

Macromolecular rapid communications 42 2100091 2021.5

DOI Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Joint Work

Using atomic force microscopy, the photo-induced reversible changes in a block copolymer self-assembly containing an azobenzene ionic liquid, which undergoes sol–gel transition is directly observed. This is the first report on the sol–gel transition of an ABA-type block copolymer consisting of upper critical solution temperature (UCST)-type A blocks in a photoresponsive ionic liquid mixture. The sol–gel transition is accompanied by an order-to-disorder structural change, which subsequently induces a change in the ionic conductivity. Surprisingly, the photo-induced ionic conductivity and rheological changes occurs rapidly (≈30 s) despite the dense (≈80 wt%) polymeric system. The rapid structural change is probably attributable to the fast diffusion of the ionic liquid.

Direct Observation of Photo‐Induced Reversible Sol–Gel Transition in Block Copolymer Self‐Assembly Containing an Azobenzene Ionic Liquid

Haruna Mizuno, Kei Hashimoto, Keisuke Shigenobu, Hisashi Kokubo, Kazuhide Ueno, Masayoshi Watanabe

Macromolecular Rapid Communications 42 ( 10 ) 210009-1 - 210009-5 2021.5 [Reviewed]

Thermodynamic aspect of sulfur, polysulfide anion and lithium polysulfide: Plausible reaction path during discharge of lithium-sulfur battery

Language：English Publishing type：Research paper (scientific journal) Joint Work

Seiji Tsuzuki, Tomoaki Kaneko, Keitaro Sodeyama, Yasuhiro Umebayashi, Wataru Shinoda, Shiro Seki, K … Show more authors

Physical chemistry chemical physics 23 ( 11 ) 6832 - 6840 2021.2 [Reviewed]

Towards practical cells: Combined use of sparingly solvating electrolyte and titanium black as cathode additive for high-energy-density lithium–sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Jiali Liu, Shanglin Li, Mayeesha Marium, Binshen Wang, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watana … Show more authors

Sustainable Energy & Fuels 5 ( 6 ) 1821 - 1831 2021.2 [Reviewed]

Towards practical cells: combined use of titanium black as a cathode additive and sparingly solvating electrolyte for high-energy-density lithium–sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Joint Work

Liu Jiali, Li Shanglin, Marium Mayeesha, Wang Binshen, Ueno Kazuhide, Dokko Kaoru, Watanabe Masayos … Show more authors

Sustainable Energy & Fuels 5 1821 - 1831 2021.2

Understanding the Reductive Decomposition of Highly Concentrated Li Salt/Sulfolane Electrolytes during Li Deposition and Dissolution

Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry Joint Work

The lithium–sulfur (Li–S) battery is considered one of the most promising technologies for next-generation energy storage. To realise its practical applications, electrodes with high areal sulfur loading, low-cost raw materials, and easily accessible fabrication processes are essential. Herein, we demonstrated the effectiveness of a commercially available black pigment, titanium black (TiB), as a multi-functional additive for sulfur electrodes. Benefiting from the amphipathic nature of TiB, it was easy to obtain a homogenous coating on a current collector (>4 mg cm^(−2)) by applying a traditional slurry containing aqueous carboxymethyl cellulose/styrene-butadiene rubber as a binder. Contact angle measurements revealed much better electrolyte wettability for the electrode with the addition of TiB. Combined with a sparingly solvating electrolyte based on sulfolane and Li[N(SO_2CF_3)_2], the electrode showed excellent cycling performance and high coulombic efficiency at a relatively high current density. Finally, pouch cells were fabricated with a low electrolyte/sulfur (E/S) ratio of 3.2 μL mg^(−1), and a high energy density of 280 W h kg^(−1) was achieved. Subsequent investigation of the gassing behaviour revealed that swelling of the charged cells at 60 °C was suppressed for half a month. This study may pave the way for designing Li–S batteries with practical utility.

Yosuke Ugata, Ryoichi Tatara, Toshihiko Mandai, Kazuhide Ueno, Masayoshi Watanabe, Kaoru Dokko

ACS Applied Energy Materials 4 ( 2 ) 1851 - 1859 2021.2 [Reviewed]

Anion effects on Li ion transference number and dynamic ion correlations in glyme–Li salt equimolar mixtures

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Publications Joint Work

Li deposition and dissolution in highly concentrated electrolytes consisting of sulfolane (SL) and two amide-type Li salts, LiN(SO2CF3)2 (LiTFSA) and LiN(SO2F)2 (LiFSA), were investigated. The chronopotentiometry test of Li/Cu cells containing these two electrolytes demonstrated that the reversibility of Li deposition/dissolution and the cycling performance were better in the LiFSA/SL electrolyte than in the LiTFSA/SL electrolyte. Gas analysis with electrochemical mass spectroscopy revealed that the SL molecules were reduced to form tetrahydrothiophene (THT) and butane in the LiTFSA/SL electrolyte during Li deposition. In contrast, these side reactions were significantly suppressed in the LiFSA/SL electrolyte. The X-ray photoelectron spectroscopy analysis for the deposited Li in the LiTFSA/SL electrolyte suggests that Li2O and sulfurous compounds were formed on the Li surface by the reductive decomposition of SL. For the LiFSA/SL electrolyte, the LiF-rich passivation layer derived from the FSA anion could effectively suppress further decomposition of SL, resulting in highly reversible Li deposition and dissolution.

Keisuke Shigenobu, Masayuki Shibata, Kaoru Dokko, Masayoshi Watanabe, Kenta Fujii, Kazuhide Ueno

Physical chemistry chemical physics 23 ( 4 ) 2622 - 2629 2021.1 [Reviewed]

Molecularly tunable polyanions for single-ion conductors and poly (solvate ionic liquids)

Language：English Publishing type：Research paper (scientific journal) Joint Work

Wenxu Zhang, Shuting Feng, Mingjun Huang, Bo Qiao, Keisuke Shigenobu, Livia Giordano, Jeffrey Lopez … Show more authors

Chemistry of materials 33 ( 2 ) 524 - 534 2021.1 [Reviewed]

Solvation Structure of Li+ in Concentrated Acetonitrile and N,N-Dimethylformamide Solutions Studied by Neutron Diffraction with 6Li/7Li Isotopic Substitution Methods

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Publications Joint Work

Yasuo Kameda, Shu Saito, Aoi Saji, Yuko Amo, Takeshi Usuki, Hikari Watanabe, Nana Arai, Yasuhiro Um … Show more authors

The Journal of Physical Chemistry B 124 ( 46 ) 10456 - 10464 2020.11 [Reviewed]

Microphase-separated structures of ion gels consisting of ABA-type block copolymers and an ionic liquid: A key to escape from the trade-off between mechanical and transport properties

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Publications Joint Work

Haruna Mizuno, Kei Hashimoto, Ryota Tamate, Hisashi Kokubo, Kazuhide Ueno, Xiang Li, Masayoshi Wata … Show more authors

Polymer 206 122849-1 - 122849-8 2020.10 [Reviewed]

Effects of fluoroethylene carbonate addition to Li-glyme solvate ionic liquids on their ionic transport properties and Si composite electrode performance

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier Joint Work

Upon combination of an ionic liquid (IL) with an amphiphilic ABA-type triblock copolymer, the insoluble A blocks aggregate to form mechanical frameworks and the soluble B blocks form ion-transport paths by incorporating the IL. Consequently, a self-standing ion gel, exhibiting the characteristic high ionic conductivity of ILs, can be obtained. In this study, we investigated the effect of microstructures formed by the block copolymer (spherical, cylindrical, gyroid, and lamellar structures) on the ionic conductivity and mechanical properties of the ion gel by focusing on the microstructures. As a result, an ion gel that formed an isotropic bicontinuous structure was successfully obtained via a heat-induced order-order transition. The structure was maintained even at room temperature, and the ion gel having a bicontinuous structure exhibited favorable mechanical properties (storage modulus, G' similar to 1.0 MPa) and good ionic conductivity (sigma similar to 0.1 mS cm(-1)). In contrast, the ion gels having anisotropic structures (cylindrical structure) exhibited weaker mechanical properties and lower ionic conductivity. The characteristics of bicontinuous structures may be the key to resolving the trade-off between mechanical and transport properties of electrolyte materials for electrochemical devices.

Hitoshi Shobukawa, Keisuke Shigenobu, Shoshi Terada, Shinji Kondou, Kazuhide Ueno, Kaoru Dokko, Mas … Show more authors

Electrochimica Acta 353 136559 2020.9 [Reviewed]

Effects of Anion on Liquid Structures of Ionic Liquids at Graphene Electrode Interface Analyzed by Molecular Dynamics Simulations

Language：English Publishing type：Research paper (scientific journal) Joint Work

Seiji Tsuzuki, Takenobu Nakamura, Tetsuya Morishita, Wataru Shinoda, Shiro Seki, Yasuhiro Umebayash … Show more authors

Batteries & Supercaps 3 ( 7 ) 658 - 667 2020.7 [Reviewed]

Structures and Electrochemistry of γ‑Butyrolactone Solvates of Na Salts

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ryoichi Tatara, So Nishimura, Yukihiro Okamoto, Kazuhide Ueno, Masayoshi Watanabe, Kaoru Dokko

The Journal of Physical Chemistry C 124 ( 29 ) 15800 - 15811 2020.6 [Reviewed]

Solvent effects on Li ion transference number and dynamic ion correlations in glyme- and sulfolane-based molten Li salt solvates

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Phase behaviors, solvate structures, Na+ transport properties, electrochemical stability, and battery performance of binary Na salt and γ-butyrolactone (GBL) mixtures have been studied systematically. A concentrated [sodium bis(fluorosulfonyl)amide (NaFSA)]/[GBL] = 1/1 mixture remains in the liquid state at room temperature, and a single crystal of the same composition is obtained below room temperature. The Na metal/electrolyte interface is stabilized and continuous electrolyte decomposition is suppressed in molten [NaFSA]/[GBL] = 1/1, whereas GBL solvates of NaN(SO2CF3)2 (NaTFSA) and NaPF6 exhibit a continual increase in interfacial resistance at the Na metal electrode. Solvent-bridged (Na+−GBL−Na+) and anion-bridged (Na+−FSA−−Na+) structures are observed in the [NaFSA]/[GBL] = 1/1 single crystal. These ligand-bridged structures produce a remarkably high Na+ transference number of 0.84 due to dynamic ligand-exchange conduction of Na+ in the electrolyte. Although the ionic conductivity of [NaFSA]/[GBL] = 1/1 is less than that of typical Na+-based electrolytes, the rate capability of a Na0.44MnO2 electrode in molten [NaFSA]/[GBL] = 1/1 is slightly greater than that in 1 mol dm-3 NaPF6/propylene carbonate. This observation is attributed to a high Na+ transference number, which suppresses the development of a concentration gradient in Na+ batteries under anion-blocking conditions. These observations indicate that not only ionic conductivity but also Na+ transference number are essential electrolyte properties for achieving high rate capabilities in Na batteries.

Keisuke Shigenobu, Kaoru Dokko, Masayoshi Watanabe, Kazuhide Ueno

Physical Chemistry Chemical Physics 20 ( 27 ) 15214 - 15221 2020.6 [Reviewed]

Molten Li Salt Solvate-Silica Nanoparticle Composite Electrolytes with Tailored Rheological Properties

Language：English Publishing type：Research paper (scientific journal) Joint Work

MARIUM Mayeesha, UENO Kazuhide, DOKKO Kaoru, WATANABE Masayoshi

Electrochemistry 88 ( 3 ) 174 - 177 2020.5 [Reviewed]

Speciation Analysis and Thermodynamic Criterion of Solvate Ionic Liquids; Whether Ionic Liquids or Super-Concentrated Solutions?

Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人電気化学会 Joint Work

Nanocomposite electrolytes comprising molten Li salt solvates (MLSs) and inorganic fillers provide liquid-like processing and reasonably high Li ion transport properties. Thus, they can be potentially used as thermally-stable and mechanically-robust electrolytes. In this study, nanocomposite electrolytes exhibiting two distinct non-Newtonian rheological responses, i.e., shear thinning and shear thickening behaviors, were prepared using glyme- and sulfolane-based molten Li salt solvates and hydrophilic fumed silica without any surface modification of the silica. The rheological responses strongly depended on the anionic structure of the MLSs. The MLS-silica composites containing bis(trifluoromethanesulfonyl)amide (TFSA) and BF4 anions formed a shear thinning gel and shear thickening fluid, respectively. The characteristic rheological properties (elastic modulus for the shear thinning gel and the maximum peak viscosity and critical shear rate for the shear thickening system) were extensively tailored by the silica content in addition to the chemical structure of the MLSs, while the changes in their ion transport properties were moderate even in the presence of silica fillers.

Other Link： https://ci.nii.ac.jp/naid/130007840150

Arai N, Watanabe H, Nozaki E, Seki S, Tsuzuki S, Ueno K, Dokko K, Watanabe M, Kameda Y, Umebayashi Y

The Journal of Physical Chemistry Letters 11 ( 11 ) 4517 - 4523 2020.4 [Reviewed]

Effect of network homogeneity on mechanical, thermal and electrochemical properties of solid polymer electrolytes prepared by homogeneous 4-arm poly(ethylene glycols)

Language：English Publishing type：Research paper (scientific journal) Joint Work

Monami Tosa, Kei Hashimoto, Hisashi Kokubo, Kazuhide Ueno, Masayoshi Watanabe

Soft Matter 16 ( 17 ) 4290 - 4298 2020.4 [Reviewed]

Liquid‐State Optoelectronics Using Liquid Metal

Language：English Publishing type：Research paper (scientific journal) Joint Work

Takashi Kozaki, Satoshi Saito, Yota Otsuki, Ryosuke Matsuda, Yutaka Isoda, Takuma Endo, Fumika Naka … Show more authors

Advanced Erectonic Materials 6 ( 3 ) 2020.3 [Reviewed]

Highly concentrated LiN(SO2CF3)2/dinitrile electrolytes: Liquid structures, transport properties, and electrochemistry

Language：English Publishing type：Research paper (scientific journal) Joint Work

Yosuke Ugata, Ryoichi Tatara, Kazuhide Ueno, Kaoru Dokko and Masayoshi Watanabe

Journal of Chemical Physics 152 ( 10 ) 104502-1 - 104502-12 2020.3 [Reviewed]

DOI Web of Science PubMed CiNii Research Repository

Language：English Publishing type：Research paper (scientific journal) Publisher：AIP Joint Work

Liquid structures, transport properties, and electrochemical properties of binary mixtures of lithium bis(trifluoromethanesulfonyl)amide (LiTFSA) and dinitrile solvents [succinonitrile (SN), glutaronitrile (GN), and adiponitrile (ADN)] were investigated. In the LiTFSA/SN and LiTFSA/ADN systems, the stable crystalline solvates of LiTFSA–(SN)1.5 [melting point (Tm): 59 °C] and LiTFSA–(ADN)1.5 (Tm: 50 °C) were formed, respectively. In contrast, the LiTFSA/GN mixtures of a wide range of compositions were found to be glass-forming liquids at room temperature. Raman spectroscopy of LiTFSA/GN liquid mixtures revealed that increasing the LiTFSA concentration results in the formation of the solvent-bridged network structure Li+–GN–Li+. In addition, the considerable formation of contact ion pairs and ionic aggregates was observed in highly concentrated electrolytes. In the liquids, the Li+ ion dynamically exchanged ligands (GN and TFSA) and higher LiTFSA concentrations led to an increase in the ratio of the self-diffusion coefficients of Li+ and TFSA−, DLi/DTFSA, as determined by pulsed field gradient NMR spectroscopy. The Li+ transference number (tLi+ ) of the [LiTFSA]/[GN] = 1/1.5 electrolyte in an electrochemical cell under anion-blocking conditions was estimated to be as high as 0.74. Furthermore, electrochemical measurements revealed that the reductive stability of the LiTFSA/GN electrolyte increases with increasing LiTFSA concentration. A [LiTFSA]/[GN] = 1/1.5 electrolyte is stable against the Li metal electrode, provided that the polarization is relatively small. Owing to high tLi+ , a Li–S battery with the [LiTFSA]/[GN] = 1/1.5 electrolyte showed a high rate discharge capability despite its low ionic conductivity (0.21 mS cm−1) at room temperature.

High Transference Number of Na Ion in Liquid-State Sulfolane Solvates of Sodium Bis (fluorosulfonyl) amide

Yukihiro Okamoto, Seiji Tsuzuki, Ryoichi Tatara, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

The Journal of Physical Chemistry C 124 ( 8 ) 4459 - 4469 2020.1 [Reviewed]

Redox-active glyme–Li tetrahalogenoferrate (iii) solvate ionic liquids for semi-liquid lithium secondary batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

The phase behavior, Na+ coordination structures, and transport and electrochemical properties of binary mixtures of NaN(SO2F)2 (NaFSA) and sulfolane (SL) solvent were investigated. The NaFSA and SL form stable solvates at molar ratios [NaFSA]/[SL] = 1/3 and 1/0.5, and there is a crystallinity gap in the range 1/1.6 ≤ [NaFSA]/[SL] ≤ 1/0.8. In the crystals of both NaFSA-(SL)3 and NaFSA-(SL)0.5, the solvent-bridged Na+−SL−Na+ and anion-bridged Na+−FSA−Na+ structures are formed. In the crystallinity gap, the mixtures remain liquid at room temperature and can be regarded as molten SL-solvates of NaFSA. The Raman spectra of the molten solvates suggest that the solvent- and anion-bridged structures are partially maintained even in the liquid. However, Na+ ions exchange the ligands (solvent and anion) dynamically in the liquids. This significantly affects the Na+ ion transport in the liquids under an anion-blocking condition. The Na+ ion transference numbers (tNa+) of molten solvates were estimated using symmetric Na/Na cells, and a molten solvate of [NaFSA]/[SL] = 1/1 exhibited a high tNa+ of 0.8. Charge and discharge tests of a Na/Na0.44MnO2 battery were performed with the molten solvate as the electrolyte. The rate capability of the battery was found to be significantly affected by tNa+ in the electrolyte.

Yuta Kemmizaki, Yu Katayama, Hiromori Tsutsumia, Kazuhide Ueno

RSC Advances 10 ( 7 ) 4129 - 4136 2020.1 [Reviewed]

Rheological and Ionic Transport Properties of Nanocomposite

Language：English Publishing type：Research paper (scientific journal) Joint Work

Mayeesha Marium, Mahfuzul Hoque, Muhammed Shah Miran, Morgan L. Thomas, Izuru Kawamura, Kazuhide Ue … Show more authors

Langmuir 36 ( 1 ) 148 - 158 2020.1 [Reviewed]

Graphite–Lithium Sulfide Battery with a Single-Phase Sparingly Solvating Electrolyte

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Joint Work

Taisho Seita, Yoshiharu Matsumae, Jiali Liu, Ryoichi Tatara, Kazuhide Ueno, Kaoru Dokko, Masayoshi … Show more authors

ACS Energy Letters 5 ( 1 ) 1 - 7 2020.1

Effects of Polysulfide Solubility and Li Ion Transport on Performance of Li–S Batteries Using Sparingly Solvating Electrolytes

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Masato Yanagi, Kazuhide Ueno, Ayumi Ando, Shanglin Li, Yoshiharu Matsumae, Jiali Liu, Kaoru Dokko, … Show more authors

Journal of The Electrochemical Society 167 ( 7 ) 2020.1 [Reviewed]

A Stretchable Lithium-ion Battery Using Liquid-metal Nano Particle

Language：English Publishing type：Research paper (scientific journal) Publisher：Electrochemical Society Joint Work

Mizuguchi Satoru, Endo Takuma, Matsuda Ryosuke, Ueno Kazuhide, Ota Hiroki

The Proceedings of the Symposium on Micro-Nano Science and Technology 2020 ( 0 ) 28A3 - MN3-1 2020

Liquid Metal Electrodes towards Conducting Agent and Binder of printed Li-ion Batteries

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society of Mechanical Engineers Joint Work

Stretchable lithium-ion batteries have been highly demanded in the IoT society. Liquid-metal (LM) has highly stretchable and deformable, and it has self-healing properties associated with charge-discharge. Here, we investigated the electrochemical characteristics and improvement of robustness using liquid-metal nano particles (LMNP) electrode on stretchable lithium-ion batteries. LMNP was prepared by ultrasonication of the liquid metal alloy composed of Ga and Sn. Stretchable LMNP electrode was fabricated by coating the slurry including LMNP onto a porous silicone rubber substrate. The electrodes of coin cells were tested after 100 % tensile strain 50 times or 100 times. The cells were galvanostatically cycled and indicated higher robustness than stretchable SiNP electrode. And we fabricated batteries using stretchable electrodes and confirmed the batteries could work.

Other Link： https://ci.nii.ac.jp/naid/130008053245

Endo Takuma, Nishitai Yuki, Ueno Kazuhide, Ota Hiroki

The Proceedings of the Symposium on Micro-Nano Science and Technology 2020 ( 0 ) 26A3 - MN2-5 2020

HIGHLY DEFORMABLE OPTOELECTRONICS USING LIQUID METAL

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society of Mechanical Engineers Joint Work

The liquid metal is in a liquid state at room temperature and compatible with easily printing process. In this study, liquid metal composite composed of liquid metal, lithium titanate (LTO), and nickel powder was utilized as a conductive agent and binder for the printing process of lithium-ion batteries. Liquid metal electrodes were prepared by mixing the liquid metal with LTO and nickel powder as the anode. The composite was coated on copper foil to form an anode. Using the anode and counter electrode made by carbon coated LFP, coin cell was assembled and the functionality was evaluated. The results showed that the electrode could be used as the anode of the lithium-ion battery. This electrode is expected to be used for printed batteries, which lead easy integration and mechanical flexibility.

Other Link： https://ci.nii.ac.jp/naid/130008053310

Kozaki, T; Satoshi, S; Otsuki, Y; Matsuda, R; Isoda, Y; Endo, T; Nakamura, F; Araki, T; Furukawa, T … Show more authors

2020 33RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2020) 1230 - 1233 2020

Language：Japanese Publishing type：Research paper (scientific journal) Joint Work

Dynamic Chelate Effect on the Li+-Ion Conduction in Solvate Ionic Liquids

Nana Arai, Hikari Watanabe, Tsuyoshi Yamaguchi, Shiro Seki, Kazuhide Ueno, Kaoru Dokko, Masayoshi … Show more authors

The Journal of Physical Chemistry C 123 ( 50 ) 30228 - 30233 2019.12 [Reviewed]

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Excellent dispersibility of single-walled carbon nanotubes in highly concentrated electrolytes and application to gel electrode for Li-S batteries

Ryota Tamate, Aya Saruwatari, Azusa Nakanishi, Yoshiharu Matsumae, Kazuhide Ueno, Kaoru Dokko, Masa … Show more authors

Electrochemistry communications 109 2019.12 [Reviewed]

Thermodynamic Effect of Anion Activity on Electrochemical Reactions Involving Li+ Ions in Room‐Temperature Ionic Liquids

Language：English Publishing type：Research paper (scientific journal) Joint Work

Dr. Ryoichi Tatara ,Prof. Kazuhide Ueno ,Prof. Kaoru Dokko ,Prof. Masayoshi Watanabe

ChemElectroChem 17 ( 6 ) 2019.8

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Online Library Joint Work

Glyme–Li salt equimolar molten solvates with iodide/triiodide redox anions

Keisuke Shigenobu, Azusa Nakanishi, Kazuhide UenoORCID,Kaoru DokkoORCID,Masayoshi Watanabe

Journals, Books and Databases ( 9 ) 22668 - 22675 2019.7

Language：English Publishing type：Research paper (scientific journal) Publisher：The Royal Society of Chemistry Joint Work

Temperature Dependence of Self-Diffusion Coefficients of Ions and Solvents in Ethylene Carbonate, Propylene Carbonate, and Diethyl Carbonate Single Solutions and Ethylene Carbonate + Diethyl Carbonate Binary Solutions of LiPF6 Studied by NMR

Azusa Nakanishi,Kazuhide Ueno,Daiki Watanabe,Yosuke Ugata,Yoshiharu Matsumae,Jiali Liu,MorganL. Tho … Show more authors

The Journal of Physical Chemistry C ( 123,23 ) 14229 - 14238 2019.5

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Publications Joint Work

Li-ion hopping conduction in highly concentrated lithium bis(fluorosulfonyl)amide/dinitrile liquid electrolytes

Yosuke Ugata, Morgan L. Thomas, Toshihiko Mandai, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Journals, Books and Databases ( 21 ) 9759 - 9768 2019.4 [Reviewed]

Language：English Publishing type：Research paper (scientific journal) Publisher：The Royal Society of Chemistry’s Single Work

Effects of Sulfur Loading, Cathode Porosity, and Electrolyte Amount on Li-S Battery Performance with Solvate Ionic Liquid Electrolyte

Yoshiharu MATSUMAE, Kenzo OBATA, Ayumi ANDO, Masato YANAGI, Yutaro KAMEI, Kazuhide UENO, Kaoru DOKK … Show more authors

Electrochemistry 87 ( 5 ) 254 - 259 2019.4

Language：English Publishing type：Research paper (scientific journal) Publisher：J-STAGE Joint Work

Polymer electrolytes based on a homogeneous poly(ethylene glycol)network and their application to polymer actuators

Ryosuke Shioiri, Hisashi Kokubo, Tatsuhiro Horii, Yumi Kobayashi, Kei Hashimoto,Kazuhide Ueno, Masa … Show more authors

Electrochimica Acta 298 866 - 873 2019.3

Language：English Publishing type：Research paper (scientific journal) Joint Work

Ionic transport in highly concentrated lithium bis(fluorosulfonyl)amide electrolytes with ketosolvents: structural implications for ionhopping conduction in liquid electrolytes

Shinji Kondou,Morgan L. Thomas,Toshihiko Mandai,Kazuhide Ueno,Kaoru Dokko,Masayoshi Watanabe

Phys. Chem. Chem. Phys ( 21 ) 5097 - 5105 2019.2 [Reviewed]

Language：English Publishing type：Research paper (scientific journal) Single Work

1．リチウム硫黄電池用電解液

上野和英, 獨古薫, 渡邉正義

電気化学 87 ( 0 ) 195 - 199 2019

Liquid-state electrical components using photoresponsive ionic liquid

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：公益社団法人電気化学会 Joint Work

Other Link： https://ci.nii.ac.jp/naid/130007703260

Kozaki Takashi, Maruo Shoji, Watanabe Masayoshi, Ueno Kazuhide, Ota Hiroki, Saito Satoshi, Otsuki Y … Show more authors

The Proceedings of the Symposium on Micro-Nano Science and Technology 2019 ( 0 ) 2019

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Society of Mechanical Engineers Joint Work

Liquid-state electronics utilizing functional liquids confined in soft templates as the sensing and actuating component present the ideal platform for enabling conformal coverage of electronic systems on curved and soft surfaces. However, to date, optoelectronic devices based on functional liquid materials as represented by photodetectors and optical memories still have not been proposed; this advancement is crucial to scaling up current liquid-state devices to a system level. Here, this study proposes optoelectronic devices based on liquid metal and photo-switchable ionic liquid with liquid-liquid heterojunction technology. The sensing and memory schemes we present are generic for different liquid-state devices, enabling different functionality to be added to the liquid-state electronics. As a proof of concept, we demonstrate a light sensor composed of the ionic liquid, and an optical memory using a composite of the ionic liquid and polypropylene glycol. These devices are important advancements towards the realization of liquid-state electronic systems.

Other Link： https://ci.nii.ac.jp/naid/130007846798

Key factor governing the physicochemical properties and extent of proton transfer in proticionic liquids: DpKa or chemical structure?

Muhammed Shah Miran,Mahfuzul Hoque,Tomohiro Yasuda,Seiji Tsuzuki,Kazuhide Ueno,Masayoshi Watanabe

Phys. Chem. Chem. Phys ( 21 ) 418 - 426 2018.12

Liquid structures and transport properties of lithium bis(fluorosulfonyl)amide/glyme solvate ionic liquids for lithium batteries

Language：English Publishing type：Research paper (scientific journal) Joint Work

Shoshi Terada, Kohei Ikeda, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Aust. J. Chem. 2018.9 [Reviewed] [Invited]

Language：English Publishing type：Research paper (scientific journal) Publisher：CSIRO Publishing Joint Work

Other Link： http://www.publish.csiro.au/ch/Fulltext/CH18270

Enhanced electrochemical stability of molten Li salt hydrate electrolytes by addition of divalent cations

Shinji Kondou, Erika Nozaki, Shoshi Terada, Morgan L. Thomas, Kazuhide Ueno, Yasuhiro Umebayashi, K … Show more authors

J. Phys. Chem. C 122 ( 35 ) 20167–20175 2018.8 [Reviewed]

Glyme-sodium bis(fluorosulfonyl)amide complex electrolytes for sodium ion batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Other Link： https://pubs.acs.org/doi/abs/10.1021/acs.jpcc.8b06251

Shoshi Terada, Hiroko Susa, Seiji Tsuzuki, Toshihiko Mandai, Kazuhide Ueno, Kaoru Dokko, Masayoshi … Show more authors

J. Phys. Chem. C 122 ( 29 ) 16589–16599 2018.7 [Reviewed]

Soft materials based on colloidal self-assembly in ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society Joint Work

Other Link： https://pubs.acs.org/doi/10.1021/acs.jpcc.8b04367

Kazuhide Ueno

Polym. J. 2018.6 [Reviewed] [Invited]

Protic ionic liquids with primary alkylamine-derived cations: the dominance of hydrogen bonding on observed physicochemical properties

Language：English Publishing type：Research paper (scientific journal) Single Work

Other Link： https://www.nature.com/articles/s41428-018-0083-1

Mahfuzul Hoque, Morgan L. Thomas, Muhammed Shah Miran, Mio Akiyama, Mayeesha Marium, Kazuhide Ueno, … Show more authors

RSC Adv. 8 ( 18 ) 9790 - 9794 2018.2 [Reviewed]

Redox active glyme-Li salt solvate ionic liquids based on tetrabromoferrate(III)

Language：English Publishing type：Research paper (scientific journal) Publisher：RSC Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2018/ra/c8ra00402a#!divAbstract

Yuta Kemmizaki, Hiromori Tsutsumi, Kazuhide Ueno

Electrochemistry 86 ( 2 ) 46 - 51 2018.1 [Reviewed]

Electrolyte composition in Li/O₂ batteries with LiI redox mediators: solvation effects on redox potentials and implications for redox shuttling

Language：English Publishing type：Research paper (scientific journal) Publisher：electrochemical society of japan Joint Work

Other Link： https://www.jstage.jst.go.jp/article/electrochemistry/advpub/0/advpub_17-00075/_article/-char/ja/

Azusa Nakanishi, Morgan L. Thomas Hoi-Min Kwon, Yuki Kobayashi, Ryoichi Tatara, Kazuhide Ueno, Kaor … Show more authors

J. Phys. Chem. C 122 ( 3 ) 1522 - 1534 2018.1 [Reviewed]

Molecular dynamics study of thermodynamic stability and dynamics of [Li(Glyme)]+ complex in lithium-glyme solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.7b11859

Wataru Shinoda, Yuta Hatanaka, Masashi Hirakawa, Susumu Okazaki, Seiji Tsuzuki, Kazuhide Ueno, Masa … Show more authors

J. Chem. Phys. 2018.1 [Reviewed]

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://aip.scitation.org/doi/full/10.1063/1.5009814

Direct Evidence for Li Ion Hopping Conduction in Highly Concentrated Sulfolane-Based Liquid Electrolytes

Kaoru Dokko,Daiki Watanabe,Yosuke Ugata,Morgan L. Thomas,Seiji Tsuzuki,Wataru Shinoda,Kei Hashimoto … Show more authors

THE JOURNAL OF PHYSICAL CHEMISTRY B ( 122 ) 10736 - 10745 2018 [Reviewed]

From Ionic Liquids to Solvate Ionic Liquids: Challenges and Opportunities for Next Generation Battery Electrolytes

Language：English Publishing type：Research paper (scientific journal) Joint Work

Watanabe Masayoshi, Dokko Kaoru, Ueno Kazuhide, Thomas Morgan L.

Bulletin of the Chemical Society of Japan 91 ( 11 ) 1660 - 1682 2018 [Reviewed] [Invited]

Polymer electrolytes containing solvate ionic liquids: a new approach to achieve high ionic conductivity, thermal stability, and a wide potential window

Language：English Publishing type：Research paper (scientific journal) Publisher：公益社団法人日本化学会 Joint Work

Certain concentrated mixtures of lithium salt and solvent (ligand) are no longer simple solutions, but categorized as solvate ionic liquids (SILs), where the solvent strongly coordinates to the cation to form a solvate, a negligible amount of free solvent remains, and thus the SIL consists of the solvate cation and the anion. Typical examples are mixtures of lithium bis(trifluoromethane sulfonyl)amide (Li[TFSA]) and certain glymes <img align="middle" src="./Graphics/abst-20180216_1.png"/>. The successful formation of a SIL greatly depends on both the ligand and lithium salt structures. To obtain robust and long-lived solvates, a ligand exhibiting a chelate effect is essential and n = 3 and 4 (i.e. triglyme and tetraglyme) are suitable for the formation of lithium solvates. The Lewis basicity of the lithium salt anion also significantly affects the formation of SILs. Specifically, a weak Lewis basicity promotes the formation of a SIL, since the ligand-Li+ interaction overwhelms the Li+-anion interaction. SILs can be diluted with rather low polarity solvents to increase the ionic conductivity, where the solvate structure is maintained even after the dilution. SILs exhibit unique features as electrolytes, including the enhancement of oxidation stability of the component glymes, unique Li+ transport through ligand exchange when interfacial electrochemical reactions are occurring, the inhibition of aluminum corrosion when Al foil is used as a cathode current collector, poorly-solubilizing towards ionic electroactive materials, and electrochemical graphite intercalation reactions. These features greatly enhance the possibility for application of SILs as next generation lithium battery electrolytes. Furthermore, new polymer electrolytes containing SILs have been proposed, simultaneously enabling film-processability, high ionic conductivity, thermal stability, and a wide potential window. Preservation of the solvate structure in the polymeric phases is pivotal to such achievements.

Other Link： https://ci.nii.ac.jp/naid/130007511409

Yuzo Kitazawa, Kaori Iwata, Ryosuke Kido, Satoru Imaizumi, Seiji Tsuzuki, Wataru Shinoda, Kazuhide … Show more authors

Chem. Mater. 30 ( 1 ) 252 - 261 2017.12 [Reviewed]

Long-range ion-ordering in salt-concentrated lithium-ion battery electrolytes: a combined high-energy X-ray total scattering and molecular dynamics simulation study

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.chemmater.7b04274

Kenta Fujii, Masaru Matsugami, Kazuhide Ueno, Koji Ohara, Michiru Sogawa, Takashi Utsunomiya, Masay … Show more authors

J. Phys. Chem. C 121 ( 41 ) 22720 - 22726 2017.9 [Reviewed]

Advanced materials based on polymers and ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.7b08243

Yuzo Kitazawa, Kazuhide Ueno, Masayoshi Watanabe

Chem. Rec. 2017.9 [Reviewed] [Invited]

Steric effect on Li+ coordination and transport properties in polyoxetane-based polymer electrolytes bearing nitrile groups

Language：English Publishing type：Research paper (scientific journal) Publisher：John Wiley & Sons, Inc. Joint Work

Other Link： http://onlinelibrary.wiley.com/doi/10.1002/tcr.201700041/full

Ryansu Sai, Kazuhide Ueno*, Kenta Fujii, Yohei Nakano, Hiromori Tsutsumi

RSC Adv. 7 ( 60 ) 37975 - 37982 2017.8 [Reviewed]

Effect of the cation on the stability of cation-glyme complexes and their interactions with the [TFSA]- anion

Language：English Publishing type：Research paper (scientific journal) Publisher：RSC Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2017/RA/C7RA07636C#!divAbstract

Seiji Tsuzuki, Toshihiko Mandai, Soma Suzuki, Wataru Shinoda, Takenobu Nakamura, Tetsuya Morishita, … Show more authors

Phys. Chem. Chem. Phys. 19 18262 - 18272 2017.7 [Reviewed]

Effect of variation in anion type and glyme length on the nanostructure of the solvate ionic liquid/graphite interface as a function of potential

Language：English Publishing type：Research paper (scientific journal) Publisher：RSC Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2017/cp/c7cp02779f#!divAbstract

Andre Cook, Kazuhide Ueno, Masayoshi Watanabe, Rob Atkin, Hua Li

J. Phys. Chem. C 121 ( 29 ) 15728 - 15734 2017.6 [Reviewed]

Soluble sulfur-based copolymers prepared from elemental sulfur and alkenyl alcohol as positive active material for lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：ACS Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.7b03414

Kazuhiro Yamabuki, Kanae Itaoka, Takahiro Shinchi, Nobuko Yoshimoto, Kazuhide Ueno, Hiromori Tsutsu … Show more authors

Polymer 117 ( 19 ) 225 - 230 2017.4 [Reviewed]

Oxygen reduction reaction in highly concentrated electrolyte solutions of lithium bis (trifluoromethanesulfonyl) amide/dimethyl sulfoxide

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S0032386117304184

Ryoichi Tatara, David G Kwabi, Thomas P Batcho, Michal Tulodziecki, Kenta Watanabe, Hoi-Min Kwon, M … Show more authors

J. Phys. Chem. C 121 ( 17 ) 9162 - 9172 2017.4 [Reviewed]

Stability of glyme solvate ionic liquid as an electrolyte for rechargeable Li−O2 batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.7b01738

Hoi-Min Kwon, Morgan L Thomas, Ryoichi Tatara, Yoshiki Oda, Yuki Kobayashi, Azusa Nakanishi, Kazuhi … Show more authors

ACS Applied Materials & Interfaces 9 ( 7 ) 6014 - 6021 2017.1 [Reviewed]

Role of polar side chains in Li+ coordination and transport properties of polyoxetane-based polymer electrolytes

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acsami.6b14449

Ryansu Sai, Kazuhide Ueno, Kenta Fujii, Yohei Nakano, Naho Shigaki, Hiromori Tsutsumi

Phys. Chem. Chem. Phys. 19 ( 7 ) 5185 - 5194 2017.1 [Reviewed]

Application of ionic liquids to energy storage and conversion materials and devices

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2017/CP/C6CP08386B#!divAbstract

Masayoshi Watanabe, Morgan L. Thomas, Shiguo Zhang, Kazuhide Ueno, Tomohiro Yasuda, Kaoru Dokko

Chem. Rev. 117 ( 10 ) 7190 - 7239 2017.1 [Reviewed] [Invited]

Suppression of water absorption by molecular design of ionic liquid electrolyte for Li-air battery

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.chemrev.6b00504

Morgan L. Thomas, Yoshiki Oda, Ryoichi Tatara, Hoi-Min Kwon, Kazuhide Ueno, Kaoru Dokko, Masayoshi … Show more authors

Adv. Energy Mater. 7 ( 3 ) 1601753 2016.10 [Reviewed]

A design approach to lithium-ion battery electrolyte based on diluted solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY Joint Work

Other Link： http://onlinelibrary.wiley.com/doi/10.1002/aenm.201601753/abstract

Kazuhide Ueno, Junichi Murai, Heejoon Moon, Kaoru Dokko, Masayoshi Watanabe

J. Electrochem. Soc. 164 ( 1 ) A6088 - A6094 2016.10 [Reviewed] [Invited]

Dissociation and diffusion of glyme-sodium bis (trifluoromethanesulfonyl) amide complexes in hydrofluoroether-based electrolytes for sodium batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：ELECTROCHEMICAL SOC INC Joint Work

Other Link： http://jes.ecsdl.org/content/164/1/A6088.abstract

Shoshi Terada, Hiroko Susa, Seiji Tsuzuki, Toshihiko Mandai, Kazuhide Ueno, Yasuhiro Umebayashi, Ka … Show more authors

J. Phys. Chem. C 120 ( 41 ) 23339 - 23350 2016.9 [Reviewed]

Optimization of pore structure of cathodic carbon supports for solvate ionic liquid electrolytes-based lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b06804

Shiguo Zhang, Ai Ikoma, Zhe Li, Kazuhide Ueno, Xiaofeng Ma, Kaoru Dokko, Masayoshi Watanabe

ACS Appl. Mater. Int. 8 ( 41 ) 27803 - 27813 2016.9 [Reviewed]

Categorizing molten salt complexes as ionic liquids and their applications to battery electrolytes

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acsami.6b09989

Kazuhide Ueno

Electrochemistry 84 ( 9 ) 674 - 680 2016.9 [Reviewed]

Li+ local structure in Li-tetraglyme solvate ionic liquid revealed by neutron total scattering experiments with the 6/7Li isotopic substitution technique

Language：English Publishing type：Research paper (scientific journal) Publisher：ELECTROCHEMICAL SOC JAPAN Single Work

Other Link： https://www.jstage.jst.go.jp/article/electrochemistry/84/9/84_16-5-E2650/_article

Soshi Saito,Hikari Watanabe,Yutaka Hayashi,Masaru Matsugami,Seiji Tsuzuki,Shiro Seki,Jose N Canongi … Show more authors

J. Phys. Chem. Lett. 7 ( 14 ) 2832 - 2837 2016.7 [Reviewed]

Gel polymer electrolytes based on poly (methacrylamide) derivative having branched pendant with terminal nitrile groups

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpclett.6b01266

Yohei Nakano, Kohsuke Shinke, Kazuhide Ueno, Hiromori Tsutsumi

Solid State Ionics 293 13 - 17 2016.6 [Reviewed]

Self-assembly of polyether diblock copolymers in water and ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S0167273816301692

Yumi Kobayashi, Yuzo Kitazawa, Takahiro Komori, Kazuhide Ueno, Hisashi Kokubo and Masayoshi Watanabe

Macromol. Rapid. Comm. 37 ( 14 ) 1207 - 1211 2016.5 [Reviewed]

Li+ local structure in hydrofluoroether diluted Li-glyme solvate ionic liquid

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY Joint Work

Other Link： http://onlinelibrary.wiley.com/doi/10.1002/marc.201600137/abstract

Soshi Saito, Hikari Watanabe, Kazuhide Ueno, Toshihiko Mandai, Shiro Seki, Seiji Tsuzuki, Yasuo Kam … Show more authors

J. Phys. Chem. B 120 ( 13 ) 3378 - 3387 2016.3 [Reviewed]

Effects of compatibility of polymer binders with solvate ionic liquid electrolytes on discharge and charge reactions of lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcb.5b12354

Toshitada Nakazawa, Ai Ikoma, Ryosuke Kido, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

J. Power Sources 307 746 - 752 2016.2 [Reviewed]

Thermal and electrochemical stability of tetraglyme-magnesium bis (trifluoromethanesulfonyl) amide complex: electric field effect of divalent cation on solvate stability

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S0378775316300453

Shoshi Terada, Toshihiko Mandai, Soma Suzuki, Seiji Tsuzuki, Katsuya Watanabe, Yutaro Kamei, Kazuhi … Show more authors

J. Phys. Chem. C 120 ( 3 ) 1353 - 1365 2016.1 [Reviewed]

Solid polymer electrolytes prepared from poly(methacrylamide) derivative having tris(cyanoethoxymethyl) group as its side chain

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.5b09779

Yohei Nakano, Kohsuke Shinke, Kazuhide Ueno, Hiromori Tsutsumi

Solid State Ionics 286 1 - 6 2015.12 [Reviewed]

Li+ solvation and ionic transport in lithium solvate ionic liquids diluted by molecular solvents

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S0167273815004488

Kazuhide Ueno, Junichi Murai, Kohei Ikeda, Seiji Tsuzuki, Mizuho Tsuchiya, Ryoichi Tatara, Toshihik … Show more authors

J. Phys. Chem. C 120 ( 29 ) 15792 - 15802 2015.12 [Reviewed]

Thermosensitive soft glassy colloidal arrays of block copolymer grafted silica nanoparticles in an ionic liquid

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/full/10.1021/acs.jpcc.5b11642

Kazuhide Ueno, Toshimichi Fukai, Masayoshi Watanabe

Polym. J. 48 ( 3 ) 289 - 294 2015.11 [Reviewed]

Lithium-tin alloy/sulfur battery with a solvate ionic liquid electrolyte

Language：English Publishing type：Research paper (scientific journal) Publisher：NATURE PUBLISHING GROUP Joint Work

Other Link： http://www.nature.com/pj/journal/v48/n3/full/pj2015105a.html

Kohei Ikeda, Shoshi Terada, Toshihiko Mandai, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Electrochemistry 83 ( 10 ) 914 - 917 2015.10 [Reviewed]

One-pot pyrolysis of lithium sulfate and graphene nanoplatelet aggregates: in situ formed Li2S/graphene composite for lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：ELECTROCHEMICAL SOC JAPAN Joint Work

Other Link： https://www.jstage.jst.go.jp/article/electrochemistry/83/10/83_15-E00101/_article

Zhe Li, Shiguo Zhang, Ce Zhang, Kazuhide Ueno, Tomohiro Yasuda, Ryoichi Tatara, Kaoru Dokko, Masayo … Show more authors

Nanoscale 7 ( 34 ) 14385 - 14392 2015.7 [Reviewed]

One-step, template-free synthesis of highly porous nitrogen/sulfur-codoped carbons from a single protic salt and their application to CO2 capture

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2015/NR/c5nr03201f#!divAbstract

Shiguo Zhang, Zhe Li, Kazuhide Ueno, Ryoichi Tatara, Kaoru Dokko, Masayoshi Watanabe

J. Mater. Chem. A 3 ( 34 ) 17849 - 17587 2015.7 [Reviewed]

Structural and aggregate analyses of (Li salt + glyme) mixtures: the complex nature of solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2015/TA/c5ta03575a#!divAbstract

Karina Shimizu, Adilson Freitas, Rob Atkin, Gregory Warr, Paul Anthony FitzGerald, Hiroyuki Doi, So … Show more authors

Phys. Chem. Chem. Phys. 17 ( 34 ) 22321 - 22335 2015.7 [Reviewed]

Adsorption of polyether block copolymers at silica-water and silica-ethylammonium nitrate interfaces

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2015/CP/C5CP03414K#!divAbstract

Zhengfei Chen, Yumi Kobayashi, Grant Bruce Webber, Kazuhide Ueno, Masayoshi Watanabe, Gregory G War … Show more authors

Langmuir 31 ( 25 ) 7025 - 7031 2015.6 [Reviewed]

Recent advance in electrolytes for lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.langmuir.5b01500

Shiguo Zhang, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Adv. Energy. Mater. 5 ( 16 ) 1500117 2015.4 [Reviewed] [Invited]

Protic-salt-derived nitrogen/sulfur-codoped mesoporous carbon for the oxygen reduction reaction and supercapacitors

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY Joint Work

Other Link： http://onlinelibrary.wiley.com/doi/10.1002/aenm.201500117/abstract

Shiguo Zhang, Ai Ikoma, Kazuhide Ueno, Zhengjian Chen, Kaoru Dokko, and Masayoshi Watanabe

ChemSusChem 8 ( 9 ) 1608 - 1617 2015.4 [Reviewed]

Hydrogen-bonding supramolecular protic salt as an "all-in-one" precursor for nitrogen-doped mesoporous carbons for CO2 adsorption

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY Joint Work

Other Link： http://onlinelibrary.wiley.com/doi/10.1002/cssc.201403320/abstract

Shiguo Zhang, Toshihiko Mandai, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Nano Energy 13 376 - 386 2015.3 [Reviewed]

Micelle structure of novel diblock polyethers in water and two protic ionic liquids (EAN and PAN)

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S2211285515001020

Zhengfei Chen, Paul A FitzGerald, Yumi Kobayashi, Kazuhide Ueno, Masayoshi Watanabe, Gregory G Warr … Show more authors

Macromolecules 48 ( 6 ) 1843 - 1851 2015.3 [Reviewed]

Li+ solvation in glyme-Li salt solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/acs.macromol.5b00082

Kazuhide Ueno, Ryoichi Tatara, Seiji Tsuzuki, Soshi Saito, Hiroyuki Doi, Kazuki Yoshida, Toshihiko … Show more authors

Phys. Chem. Chem. Phys. 17 ( 12 ) 8248 - 8257 2015.2 [Reviewed]

Solvent activity in electrolyte solutions controls electrochemical reactions in Li-ion and Li-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2015/cp/c4cp05943c#!divAbstract

Heejoon Moon, Toshihiko Mandai, Ryoichi Tatara, Kazuhide Ueno, Azusa Yamazaki, Kazuki Yoshida, Shir … Show more authors

J. Phys. Chem. C 119 ( 8 ) 3957 - 3970 2015.2 [Reviewed]

Li+ ion transport in polymer electrolytes based on a glyme-Li salt solvate ionic liquid

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp5128578

Ryosuke Kido, Kazuhide Ueno, Kaori Iwata, Yuzo Kitazawa, Satoru Imaizumi, Toshihiko Mandai, Kaoru D … Show more authors

Electrochim. Acta 175 5 - 12 2015.1 [Reviewed]

Effect of ionic size on solvate stability of glyme-based solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S0013468615000870

Toshihiko Mandai, Kazuki Yoshida, Seiji Tsuzuki, Risa Nozawa, Hyuma Masu, Kazuhide Ueno, Kaoru Dokk … Show more authors

J. Phys. Chem. B 119 ( 4 ) 1523 - 1534 2014.12 [Reviewed]

Pentaglyme-K salt binary mixtures:phase behavior, solvate structures, and physicochemical properties

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp508100s

Toshihiko Mandai, Seiji Tsuzuki, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Phys. Chem. Chem. Phys. 17 ( 4 ) 2838 - 2849 2014.12 [Reviewed]

Upper limit of nitrogen content in carbon materials

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2015/cp/c4cp05017g/unauth#!divAbstract

Shiguo Zhang, Seiji Tsuzuki, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Angew. Chem. Int. Ed. 54 ( 4 ) 1302 - 1306 2014.11 [Reviewed]

Structures of [Li(glyme)]+ complexes and their interactions with anions in equimolar mixtures of glymes and Li[TFSA]: analysis by molecular dynamics simulations

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY Joint Work

Other Link： http://onlinelibrary.wiley.com/doi/10.1002/anie.201410234/abstract

Seiji Tsuzuki, Wataru Shinoda, Masaru Matsugami, Yasuhiro Umebayashi, Kazuhide Ueno, Toshihiko Mand … Show more authors

Phys. Chem. Chem. Phys. 17 ( 1 ) 126 - 129 2014.11 [Reviewed]

Nanostructure of [Li(G4)]TFSI and [Li(G4)]NO3 solvate ionic liquids at HOPG and Au(111) electrode interfaces as a function of potential

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2015/CP/c4cp04718d#!divAbstract

Ben McLean, Hua Li, Ryan Stefanovic, Ross J. Wood, Grant B. Webber, Kazuhide Ueno, Masayoshi Watana … Show more authors

Phys. Chem. Chem. Phys. 17 ( 1 ) 325 - 333 2014.10 [Reviewed]

Enhanced performance of sulfone-based electrolytes at lithium ion battery electrodes, including the LiNi0.5Mn1.5O4 high voltage cathode

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2015/CP/C4CP04522J#!divAbstract

Leigang Xue, Kazuhide Ueno, Seung-Yul Lee, C. Austen Angell

Enhanced performance of sulfone-based electrolytes at lithium ion battery electrodes, including the LiNi0.5Mn1.5O4 high voltage cathode 262 123 - 128 2014.9 [Reviewed]

Gelation of solvate ionic liquid by self-assembly of block copolymer and characterization as polymer electrolyte

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER Joint Work

Other Link： http://www.sciencedirect.com/science/article/pii/S0378775314004224

Yuzo Kitazawa, Kaori Iwata, Satoru Imaizumi, Hyungmin Ahn, Sung Yeon Kim, Kazuhide Ueno, Moon Jeong … Show more authors

Macromolecules 47 ( 17 ) 6009 - 6016 2014.8 [Reviewed]

Mechanism of Li ion desolvation at the interface of graphite electrode and glyme-Li salt solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/ma501296m

Heejoon Moon, Ryoichi Tatara, Toshihiko Mandai, Kazuhide Ueno, Kazuki Yoshida, Naoki Tachikawa, Tom … Show more authors

J. Phys. Chem. C 118 ( 35 ) 20246 - 20256 2014.8 [Reviewed]

Chelate effects in glyme/lithium bis(trifluoromethanesulfonyl)amide solvate ionic liquids, part 2: importance of solvate-structure stability for electrolytes of lithium batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp506772f

Ce Zhang, Azusa Yamazaki, Junichi Murai, Jun-Woo Park, Toshihiko Mandai, Kazuhide Ueno, Kaoru Dokk … Show more authors

J. Phys. Chem. C 118 ( 31 ) 17362 - 17373 2014.7 [Reviewed]

Physicochemical properties of pentaglyme-sodium bis(trifluoromethanesulfonyl)amide solvate ionic liquid

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp504099q

Shoshi Terada, Toshihiko Mandai, Risa Nozawa, Kazuki Yoshida, Kazuhide Ueno, Seiji Tsuzuki, Kaoru D … Show more authors

Phys. Chem. Chem. Phys. 16 ( 23 ) 11737 - 11746 2014.4 [Reviewed]

Chelate effects in glyme/lithium bis(trifluoromethanesulfonyl)amide solvate ionic liquids, part 1: stability of solvate cations and correlation with electrolyte properties

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2014/cp/c4cp00746h#!divAbstract

Ce Zhang, Kazuhide Ueno, Azusa Yamazaki, Kazuki Yoshida, Toshihiko Mandai, Yasuhiro Umebayashi, Kao … Show more authors

J. Phys. Chem. B 118 ( 19 ) 5144 - 5153 2014.4 [Reviewed]

Criteria for solvate ionic liquids

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp501319e

Toshihiko Mandai, Kazuki Yoshida, Kazuhide Ueno, Kaoru Dokko, Masayoshi Watanabe

Phys. Chem. Chem. Phys. 16 ( 19 ) 8761 - 8772 2014.3 [Reviewed] [Invited]

Solubility of poly(methyl methacrylate) in ionic liquids in relation to solvent parameters

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2014/cp/c4cp00461b#!divAbstract

Performance of sulfone, and sulfone-containing, solvents at lithium ion battery electrodes, including the LiNi0.5Mn1.5O4 high voltage cathode

Leigang Xue, Kazuhide Ueno, Seung-Yul Lee, and C. Austen Angell

Journal of Power Sources 262 123 - 128 2014.3 [Reviewed]

Language：English Publishing type：Research paper (scientific journal) Joint Work

Kazuhide Ueno, Toshimichi Fukai,Tomomi Nagatsuka, Tomohiro Yasuda, Masayoshi Watanabe

Langmuir 30 ( 11 ) 3228 - 3235 2014.2 [Reviewed]

Phase diagrams and solvate structures of binary mixtures of glymes and Na salts

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/la404797g

Toshihiko Mandai, Risa Nozawa, Seiji Tsuzuki, Kazuki Yoshida, Kazuhide Ueno, Kaoru Dokko, Masayoshi … Show more authors

J. Phys. Chem. B 117 ( 48 ) 15072 - 15085 2013.11 [Reviewed]

Anionic effects on solvate ionic liquid electrolytes in rechargeable lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp407582m

Kazuhide Ueno, Jun-Woo Park, Azusa Yamazaki, Toshihiko Mandai, Naoki Tachikawa, Kaoru Dokko, Masayo … Show more authors

J. Phys. Chem. C 117 ( 40 ) 20509 - 20516 2013.9 [Reviewed]

Ionic liquid electrolytes for lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp407158y

Jun-Woo Park, Kazuhide Ueno, Naoki Tachikawa, Kaoru Dokko, Masayoshi Watanabe

J. Phys. Chem. C 117 ( 40 ) 20531 - 20541 2013.9 [Reviewed]

EQCM measurement of deposition and dissolution of lithium in glyme-Li salt molten complex

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp408037e

Nobuyuki Serizawa, Shiro Seki, Katsuhito Takei, Hajime Miyashiro, Kazuki Yoshida, Kazuhide Ueno, Na … Show more authors

J. Electrochem. Soc. 160 ( 9 ) A1529 - A1533 2013.7 [Reviewed]

Solvate ionic liquid, [Li(triglyme)1][NTf2], as electrolyte for rechargeable Li/air battery: discharge depth and reversibility

Language：English Publishing type：Research paper (scientific journal) Publisher：ELECTROCHEMICAL SOC INC Joint Work

Other Link： http://jes.ecsdl.org/content/160/9/A1529.abstract

Ryoichi Tatara, Naoki Tachikawa, Hoi-Min Kwon, Kazuhide Ueno, Kaoru Dokko and Masayoshi Watanabe

Chem. Lett. 42 ( 9 ) 1053 - 1055 2013.6 [Reviewed]

Solvate ionic liquid electrolyte for Li-S batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：CHEMICAL SOC JAPAN Joint Work

Other Link： https://www.jstage.jst.go.jp/article/cl/42/9/42_130420/_article

Kaoru Dokko, Naoki Tachikawa, Kento Yamauchi, Mizuho Tsuchiya, Azusa Yamazaki, Eriko Takashima, Jun … Show more authors

J. Electrochem. Soc. 160 ( 8 ) A1304 - A1310 2013.6 [Reviewed]

Solvent effect of room-temperature ionic liquids on electrochemical reactions in lithium-sulfur batteries

Language：English Publishing type：Research paper (scientific journal) Publisher：ELECTROCHEMICAL SOC INC Joint Work

Other Link： http://jes.ecsdl.org/content/160/8/A1304.abstract

Jun-Woo Park, Kento Yamauchi, Eriko Takashima, Naoki Tachikawa, Kazuhide Ueno, Kaoru Dokko, and Mas … Show more authors

J. Phys. Chem. C 117 ( 9 ) 4431 - 4440 2013.2 [Reviewed]

Anhydrous superprotonic polymer by superacid protonation of crosslinked (PNCl2)n

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp400153m

Younes Ansari, Kazuhide Ueno, Zuofeng Zhao, C. Austen Angell

J. Phys. Chem. C 117 ( 4 ) 1548 - 1553 2012.12 [Reviewed]

Lithium salt solutions in mixed sulfone and sulfone-carbonate solvents: a Walden plot analysis of the maximally conductive compositions

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp306302n

Seung-Yul Lee, Kazuhide Ueno, C. Austen Angell

J. Phys. Chem. C 116 ( 45 ) 23915 - 23920 2012.10 [Reviewed]

Glyme-Li salt equimolar molten mixtures: concentrated solutions or solvate ionic liquids?

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp3067519

Kazuhide Ueno, Kazuki Yoshida, Mizuho Tsuchiya, Naoki Tachikawa, Kaoru Dokko, Masayoshi Watanabe

J. Phys. Chem. B 116 ( 36 ) 11323 - 11331 2012.8 [Reviewed]

Heat capacities and glass transitions of ion gels

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp307378j

Osamu Yamamuro, Takenori Someya, Maiko Kohu, Takeshi Ueki, Kazuhide Ueno, Masayoshi Watanabe

J. Phys. Chem. B 116 ( 35 ) 10935 - 10940 2012.8 [Reviewed]

Microscopic insight into ion gel dynamics using neutron spesctroscopy

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp3030655

Maiko Kofu, Takenori Someya, Soichi Tatsumi, Kazuhide Ueno, Takeshi Ueki, Masayoshi Watanabe, Takur … Show more authors

Soft Matter 8 3888 - 3897 2012.6 [Reviewed]

Ionic liquids as oxidic media for electron transfer studies

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.rsc.org/en/content/articlelanding/2012/SM/C2SM25348H#!divAbstract

Kazuhide Ueno, C. Austen Angell

J. Chem. Phys. 136 244501 2012.6 [Reviewed]

Protic ionic liquids based on decahydroisoquinoline: lost superfragility and fragility-ionicity correlation

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://scitation.aip.org/content/aip/journal/jcp/136/24/10.1063/1.4729306

Kazuhide Ueno , Zuofeng Zhao, Masayoshi Watanabe, C. Austen Angell

J. Phys. Chem. B 116 ( 1 ) 63 - 70 2011.11 [Reviewed]

High conductivity, and `dry' proton motion, in guanidinium salt melts and binary solutions

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp2078727

Zuofeng Zhao, Kazuhide Ueno, C. Austen Angell

J. Phys. Chem. B 115 ( 46 ) 13467 - 13472 2011.10 [Reviewed]

On the decoupling of relaxation modes in a molecular liquid caused by isothermal introduction of 2 nm structural inhomogeneities

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp206491z

115 ( 48 ) 13994 - 13999 2011.7 [Reviewed]

From colloidal stability in ionic liquid to advanced soft materials using the unique media

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp111398r

Kazuhide Ueno, Masayoshi Watanabe

Langmuir 27 ( 15 ) 9105 - 9115 2011.1 [Reviewed] [Invited]

Thermosensitive, soft glassy and structural colored colloidal array in ionic liquid: colloidal glass to gel transition

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/la103942f

Kazuhide Ueno, Aya Inaba, Takeshi Ueki, Masashi Kondoh, Masayoshi Watanabe

Langmuir 26 ( 23 ) 18031 - 18038 2010.10 [Reviewed]

Soft glassy colloidal arrays in an ionic liquid: colloidal glass transition, ionic transport, and structural color in relation to microstructure

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/la103716q

J. Phys. Chem. B 114 ( 41 ) 13095 - 13103 2010.9 [Reviewed]

Resonance shear measurement of nanoconfined ionic liquids

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp106872w

Phys. Chem. Chem. Phys. 12 4066 - 4071 2010.3 [Reviewed]

Ionicity in ionic liquids: correlation with ionic structure and physicochemical properties

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2010/CP/b923571j#!divAbstract

Kazuhide Ueno, Hiroyuki Tokuda, Masayoshi Watanabe

Phys. Chem. Chem. Phys. 12 1649 - 1658 2010.1 [Reviewed] [Invited]

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/la901159r

Photoisomerization-induced tunable LCST phase separation of azobenzene-containing polymers in an ionic liquid

Takeshi Ueki, Ayuko Yamaguchi, Naoki Ito, Koichi Kodama, Junji Sakamoto, Kazuhide Ueno, Hisashi Kok … Show more authors

Langmuir 25 ( 16 ) 8845 - 8848 2009.7 [Reviewed]

Thermosensitive self-assembly of diblock copolymers with lower critical micellization temperatures in an ionic liquid

Language：English Publishing type：Research paper (scientific journal) Joint Work

Macromolecules 42 ( 16 ) 6239 - 6244 2009.6 [Reviewed]

Electrochromism based on structural colour changes in a polyelectrolyte gel

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/ma900922d

Kazuhide Ueno, Junji Sakamoto, Yukikazu Takeoka, Masayoshi Watanabe

J. Mater. Chem. 19 ( 27 ) 4778 - 4783 2009.5 [Reviewed]

A soft glassy colloidal array in ionic liquid, which exhibits homogeneous, nonbrilliant, and angle-independent structural colours

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2009/JM/b900261h#!divAbstract

Kazuhide Ueno, Aya Inaba, Yuta Sano, Masashi Kondoh, Masayoshi Watanabe

Chem. Commun. 24 3603 - 3605 2009.5 [Reviewed]

Colloidal interaction in ionic liquids: effects of ionic structures and surface chemistry on rheology of silica colloidal dispersions

Language：English Publishing type：Research paper (scientific journal) Joint Work

Other Link： http://pubs.rsc.org/en/Content/ArticleLanding/2009/CC/b905108b#!divAbstract

Kazuhide Ueno, Satoru Imaizumi, Kenji Hata, Masayoshi Watanabe

Langmuir 25 ( 2 ) 825 - 831 2008.12 [Reviewed]

Nanocomposite ion gels based on silica nanoparticles and an ionic liquid: ionic transport, viscoelastic properties, and microstructure

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/la803124m

Kazuhide Ueno, Kenji Hata, Toru Katakabe, Masashi Kondoh, Masayoshi Watanabe

J. Phys. Chem. B 112 ( 30 ) 9013 - 9019 2008.7 [Reviewed]

Colloidal stability of bare and polymer-grafted silica nanoparticles in ionic liquids

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/jp8029117

Kazuhide Ueno, Aya Inaba, Masashi Kondoh, Masayoshi Watanabe

Langmuir 24 ( 10 ) 5253 - 5259 2008.4 [Reviewed]

An electro- and thermochromic hydrogel as a full-color indicator

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC Joint Work

Other Link： http://pubs.acs.org/doi/abs/10.1021/la704066v

Kazuhide Ueno, Kazuki Matsubara, Masayoshi Watanabe, Yukikazu Takeoka

Adv. Mater. 19 ( 19 ) 2807 - 2812 2007.9 [Reviewed]