Development of new electrolytes for high-energy-density cathode materials for potassium-ion batteries

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K15685
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 36020:Energy-related chemistry
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Masese Titus 国立研究開発法人産業技術総合研究所, エネルギー・環境領域, 主任研究員 (70758466)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: カリウムイオン電池 / 高電位 / 電極材料 / 正極 / 電解質 / 高電圧 / 高エネルギー密度

Outline of Final Research Achievements

Aiming to design a 4V-class potassium-ion battery, we researched on a new electrolyte that can be used stably at high-voltage operation. In order to examine the stability of the new electrolyte, electrochemical performance was evaluated using various cathode materials that operate at high-voltage regimes. Conventional electrolytes that use organic solvents generally decompose when operated at high voltages leading to poor performance of the cathode materials. However, we found that electrolytes based on ionic salts (in particular pyrrolidinium-based ionic liquids) are effective in improving the electrochemical performance metrics of cathode materials such as cyclability at high-voltage operation. Moreover, we also developed new cathode materials to be coupled with ionic-liquid-based electrolytes. This study shows the prospects of developing high-voltage and high-energy-density potassium-ion batteries.

Free Research Field

電気化学、材料科学、固体化学

Academic Significance and Societal Importance of the Research Achievements

高性能カリウムイオン電池の実現は高い電圧域での作動を耐えうる新規電極材料の開発が必須である。そこで4V級カリウムイオン電池の創製を目指し、①高電位域で安定に使用できる新規電解液と②電解液に適合できる高電位系新規正極材料の研究開発を行った。得られた成果は、低コストかつ高エネルギー密度カリウムイン蓄電池の実現に資するものであり、次世代の環境・エネルギー技術としての意義だけでなく、高電圧正極材料の反応機構を解明する学術研究としての意義がある。