Development of high-voltage cathode materials for high-energy-density rechargeable potassium-ion batteries

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K14730
• 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): 2021-04-01 – 2023-03-31
• Keywords: カリウムイオン電池 / 二次電池 / 電極材料 / 電気化学 / 固体化学 / 物性論 / 数理物理学 / トポロジー

Outline of Final Research Achievements

This research project entailed the development of new layered oxide cathode materials for 4V-class rechargeable potassium-ion batteries. Galvanostatic (dis)charge measurements confirmed the new layered oxides to display voltages nearing 4 V. Moreover, high-resolution transmission electron microscopy revealed various unique topological features (defects/disorders) intrinsic in the new layered oxide materials that have implications in the electrochemical performance. Further, we successfully developed a new high-voltage layered cathode material (NaKNi2TeO6) comprising alternating arrangements of both potassium and sodium atoms in its layered framework. Finally, we unveil the possibility of inducing mixed Na- and K-ion transport electrochemistry of NaKNi2TeO6 at high voltages (~ 4V), thus epitomising it as a competent cathode candidate for the emerging dendrite-free batteries based on NaK liquid metal alloy as anodes.

Free Research Field

固体電気化学

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電位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、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、高電圧・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。