Design of Hopping Conductive Liquid Electrolytes Based on Frustrated Ion Solvation

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K19082
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 36:Inorganic materials chemistry, energy-related chemistry, and related fields
• Research Institution: Yokohama National University
• Principal Investigator: Ueno Kazuhide 横浜国立大学, 大学院工学研究院, 准教授 (30637377)
• Project Period (FY): 2022-06-30 – 2024-03-31
• Keywords: 電解液 / リチウムイオン輸率 / イオン伝導率 / 溶媒和

Outline of Final Research Achievements

Improving the performance of energy storage devices is an important issue for realizing a sustainable society. Cation transport in conventional electrolytes is governed by the viscosity of the system; since the mass transport of Li ions is the rate-limiting step under fast charge-discharge conditions in Li-ion batteries, it is desirable to develop electrolytes capable of fast cation transport property. In this study, in order to achieve efficient ion hopping transport in liquid electrolytes, we intentionally destabilized the solvation state of cations in highly concentrated electrolyte (frustrated solvation) and generated highly active alkali metal cations. The design guideline for liquid electrolytes with high ionic conductivity, high lithium ion transference number, and facile interface formation based on the frustrated ion solvation of liquid electrolyte was proposed.

Free Research Field

エネルギー化学

Academic Significance and Societal Importance of the Research Achievements

液体電解質はイオン伝導率を最重要因子とした開発が進められてきたが、高速充放電性能の向上のため、カチオン輸率が高い電解質の重要性も認識されるようになっている。しかし、低分子液体電解質で高いイオン伝導率と高いカチオン輸率の両立した報告例は皆無である。水溶液中のH+のホッピング輸送はGrotthuss機構として古くから知られているが、質量の大きなアルカリ金属カチオンのホッピング輸送の原理解明は学問的に極めて興味深い。本成果は溶媒和フラストレーションという新規概念に基づくイオンホッピング電解液の設計指針を示すものであり、関連分野の研究進展に対する貢献、社会へのインパクトや学術的な波及効果が期待できる。