Chemistry of Lithium-ion conducting sulfide-based solid electrolyte by solution process

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01610
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 26020:Inorganic materials and properties-related
• Research Institution: Hokkaido University
• Principal Investigator: Tadanaga Kiyoharu 北海道大学, 工学研究院, 教授 (90244657)
• Co-Investigator(Kenkyū-buntansha): 藤井 雄太 北海道大学, 工学研究院, 助教 (90982653) ; ROSERO CAROLINA 北海道大学, 工学研究院, 助教 (50791381)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 硫化物固体電解質 / 全固体電池 / 液相法

Outline of Final Research Achievements

The main objectives of the present study are to elucidate the reactions of precursors and solvents in solution during the liquid-phase synthesis of sulfide-based solid electrolytes, to design reaction pathways for various sulfide solid electrolytes, and to explore novel solid electrolytes.

The structure of the precursor complexes formed during the liquid-phase synthesis was analyzed, and the relationship between their thermal decomposition behavior and the resulting phase was clarified. By using both a suspension process and a dissolution-reprecipitation process, we demonstrated that the particle size of the resulting sulfide solid electrolytes can be controlled. We also showed that by using alcohol as a reaction solvent, oxythiophosphate-based solid electrolytes with oxygen incorporated into their structure were obtained.

Free Research Field

無機材料化学

Academic Significance and Societal Importance of the Research Achievements

液相法を用いて硫化物系固体電解質を合成する場合に、その前駆体の構造や前駆体の溶解挙動を理解することにより、固相法で合成が困難な結晶祖を合成できること、あるいは、得られた固体電解質の粒径を制御できることを示し、液相法の特徴を活かした硫化物系固体電解質を合成できることを明らかにした。