Liquid electrolyte formulation for rapid Li-ion hopping conduction and fast electrochemical reactions

2021 Fiscal Year Final Research Report

• Project/Area Number: 18H03926
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 36:Inorganic materials chemistry, energy-related chemistry, and related fields
• Research Institution: Yokohama National University
• Principal Investigator: DOKKO Kaoru 横浜国立大学, 大学院工学研究院, 教授 (70438117)
• Co-Investigator(Kenkyū-buntansha): 都築 誠二 横浜国立大学, 先端科学高等研究院, 非常勤教員 (10357527) ; 梅林 泰宏 新潟大学, 自然科学系, 教授 (90311836)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 電解液 / イオン伝導 / 電気化学 / 電池

Outline of Final Research Achievements

Highly concentrated electrolytes containing alkali metal salts were prepared, and the coordination structure of alkali metal ions was analyzed by spectroscopic methods. Transport properties and electrochemistry of the highly concentrated electrolytes (HCEs) were investigated. In the HCEs with certain solvents such as sulfones and dinitriles, alkali metal ions exchanged the ligands (solvent and anion) dynamically and diffused more rapidly than the ligands, i.e., hopping conduction of alkali metal ion emerged in the HCEs. The high transference numbers of alkali metal ions were effective in suppressing the concentration polarization and in achieving a relatively high-rate capability of alkali metal batteries.

Free Research Field

電気化学

Academic Significance and Societal Importance of the Research Achievements

本研究をとおして，古典的な電解質溶液論では説明できない現象である超濃厚電解液中におけるイオンホッピング伝導に関するの知見が蓄積され，新たなイオン伝導機構の理論を確立する端緒になると考えられる。また，社会的にも重要な役割を果たす蓄電池を高出力化する上で，高速にイオン輸送が可能で，電極／電解液界面における電気化学反応抵抗が小さい電解液を開発することは重要であるが，本研究で得られた知見は，蓄電池の高出力化に向けて新たな電解液の設計指針を提示するものである。