Conversion Anode Materials with High Capacity and Long Cycle Life

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K17970
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Device related chemistry
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Iwama Etsuro 東京農工大学, 工学(系)研究科(研究院), 准教授 (90726423)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: リチウムイオン電池負極 / 長寿命 / リチウム-酸素交換反応 / 金属-酸素結合制御

Outline of Final Research Achievements

This study was mainly focused on an elucidation of reaction mechanism for conversion-type anode materials which enables anomalous long cycles. Using SnO2 and Mn3O4 as model materials, the complete encapsulation of 5-10 nm metal oxides nanoparticles is the essential factor to attain the reversible conversion reaction. in situ EXAFS analysis confirmed that disappearance and reappearance of Sn-O or Mn-O bonding during charge-discharge process occurred reversibly. Furthermore, Li3VO4 and its reaction mechanism were studied as an another model material which enables long cycle life without any encapsulation.

Free Research Field

電気化学、材料科学

Academic Significance and Societal Importance of the Research Achievements

従来は可逆化が困難であった遷移金属酸化物のコンバージョン反応(リチウム-酸素交換型反応)の長期充放電サイクルを達成したこと、これを達成するために重要な要素を明らかとしたことで、電池の高容量化への寄与、ひいては低CO2環境社会の構築への貢献が期待される。