Research and Development of Aqueous Solutions with Wide Potential Windows for Rechargeable Batteries

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H03133
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Device related chemistry
• Research Institution: Kyoto University
• Principal Investigator: Miyazaki Kohei 京都大学, 地球環境学堂, 准教授 (10512783)
• Co-Investigator(Kenkyū-buntansha): 若林 裕助 東北大学, 理学研究科, 教授 (40334205)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 二次電池 / 水溶液 / 電位窓

Outline of Final Research Achievements

In order to improve the safety of rechargeable batteries, water-based rechargeable batteries using an aqueous solution as an electrolyte have been investigated, but the problem is that the potential range for stable operation is known to be narrow. In this study, we used the addition of organic sulfonates to elucidate the expansion of the potential window of aqueous electrolytes and the mechanism of their expression. An enlarged potential window was found for multiple organic sulfonates, confirming that this is a universal phenomenon. The present findings provide a new perspective that the degradation resistance of aqueous solutions can be improved by controlling the local ion concentration and structure near the electrode, which is beneficial from the viewpoint of device applications.

Free Research Field

電気化学

Academic Significance and Societal Importance of the Research Achievements

水溶液を二次電池の電解質として利用することは、コストや安全性の観点から望ましいアプローチであるが、これまでに知られている手法はコストと安全性を両立できるものではない。本研究で明らかにした有機塩を添加する手法は非常に簡便なアプローチであり、コストを抑えつつ、安全な水溶液の性能を高めることに有効である。