Investigation of determining factor on electrochemical stabilities of lithium and sodium metal battery electrolytes

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05263
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 36020:Energy-related chemistry
• Research Institution: National Institute for Materials Science
• Principal Investigator: Mandai Toshihiko 国立研究開発法人物質・材料研究機構, エネルギー・環境材料研究センター, 主任研究員 (20810592)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 蓄電池 / 電解液 / アルカリ金属 / 還元安定性 / アート錯体 / 立体構造

Outline of Final Research Achievements

Rechargeable batteries those incorporating reductive metal as the negative electrode active material can achieve an energy density higher than that of current lithium-ion batteries. In this study, we focused on Li and Na metal, which possess strong reducing power among various electrode materials, and aimed to establish a rational design guideline for a stable electrolyte that increases the charge-discharge reaction efficiency. The chemical structure-electrochemical property relationship was systematically evaluated using an art complex-based electrolyte salt as a model system because of its structural design flexibility. It was found that controlling the dissociativity of the electrolyte salt by introducing appropriate branching structure and fluorine substitution is an important guideline in creating an electrolyte that exhibit favorable electrochemical performance against Li and Na metal negative electrodes.

Free Research Field

エネルギー材料科学

Academic Significance and Societal Importance of the Research Achievements

本研究では、従来の電解液研究で取られてきた電解質分解を前提とした方法論とは根本的なコンセプトを異にし、金属負極に対して化学的に安定な電解液を開発するための設計指針を提案した。本指針に基づけば、広大な探索空間を低次元化することができ、有望材料の探索加速が期待できる。また本研究を通して得られた知見は、社会的にも切望されている高性能な次世代金属電池の実現に真に資する電解質材料を設計開発する上で、重要な指針を提示するものである。