Online ISSN : 2186-2451
Print ISSN : 1344-3542
ISSN-L : 1344-3542
Comprehensive Paper (Invited Paper)
The Award of The Electrochemical Society of Japan (Takei Award)
  • Kiyoshi KANAMURA
    2022 年 90 巻 10 号 p. 101001
    発行日: 2022/10/05
    公開日: 2022/10/05
    [早期公開] 公開日: 2022/08/10
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    Research and development of Lithium Ion Battery (LIB) have been extensively performed based on material science and cell technology. In order to accelerate the development of LIB, a multi-scale researches have to be conducted under one roof. Here, several researches from nm scale to m scale on LIB were introduced to discuss an importance of multi-scale research. Then, the new platform for LIB development was proposed based on our several researches. (1) Interfacial analysis between cathode and electrolyte in LIB by using in-situ Fourier Transform Infrared method, (2) Preparation of LiFePO4 (LFP) with carbon coating, (3) Interfacial analysis on lithium metal anode for solid electrolyte interphase (SEI), (4) Preparation of 3 dimensionally ordered macroporous separator and its application to lithium metal battery, (5) Single particle measurement for evaluation of composite electrodes, (6) Failure mode analysis of LFP/Graphite cell.

Scientific Achievement Award of The Electrochemical Society of Japan
  • Yasuaki EINAGA
    2022 年 90 巻 10 号 p. 101002
    発行日: 2022/10/05
    公開日: 2022/10/05
    [早期公開] 公開日: 2022/05/28
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    Boron-doped diamond (BDD) electrodes are next generation electrode materials and their electrochemical applications have been actively developed in recent years. They are expected to be useful electrode materials for improving the environment and for bio-medical applications. Here, examples of practical applications as electrochemical sensors, the development of in vivo real time measurements, and electrochemical organic synthesis using BDD electrodes are briefly introduced. In the second part, our recent work on the production of useful chemicals by means of the electrochemical reduction of CO2 using BDD electrodes is described. The work has attracted particular attention for its potential contribution to carbon neutrality and carbon recycling.

  • Kaoru DOKKO
    2022 年 90 巻 10 号 p. 101003
    発行日: 2022/10/05
    公開日: 2022/10/05
    [早期公開] 公開日: 2022/07/06
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    Li salts and polar solvents form solvates, and certain solvates have low melting temperatures and remain in a liquid state at room temperature. Liquid-state solvates exhibit ionic conductivity and can be used as electrolytes in lithium batteries. The author and co-workers have systematically studied the interactions of Li+ ions with solvents and anions, Li+-coordination structures, thermal properties, transport properties, and electrochemical properties in molten-solvate electrolytes. In molten solvates, almost all solvent molecules are coordinated to Li+ ions, and uncoordinated (free) solvents are rare. Additionally, anions are involved in the coordination of the Li+ ions. The molten solvate electrolytes show non-flammability and negligible vapor pressure at room temperature because of the extremely low concentration (activity) of the free solvent, which can improve the thermal stability of Li batteries. The low activity of the free solvent results in a wide electrochemical window of the molten-solvate electrolytes, thereby suppressing undesired side reactions in Li batteries. The activity of the free solvent in the electrolytes significantly affects the electrochemical reaction processes, such as the reduction reaction of sulfur (S8) in a Li–S battery and the oxygen reduction reaction (ORR) in a Li–air battery. The solubility of the reaction intermediates of the S8 cathode and the ORR decreases with the decrease in solvent activity, which enables the highly efficient charge–discharge of Li–S and Li–air batteries. In molten solvates, Li+ ions diffuse and migrate by exchanging ligands (solvents and anions). Certain molten-solvate electrolytes show high Li+ ion transference numbers over 0.5, and these high transference numbers are useful in mitigating the concentration overpotential during the charging and discharging of Li batteries at high current densities.

Young Researcher Award of The Electrochemical Society of Japan (Sano Award)
The 66th special feature “Novel Aspects and Approaches to Experimental Methods for Electrochemistry”