Chemical State Visualization of Battery Materials by Operando X-ray Spectro-Ptychography

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K15375
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 36020:Energy-related chemistry
• Research Institution: Tohoku University
• Principal Investigator: Ishiguro Nozomu 東北大学, 国際放射光イノベーション・スマート研究センター, 助教 (20752455)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: X線タイコグラフィ / X線吸収微細構造 / 蓄電材料粒子 / オペランド計測

Outline of Final Research Achievements

In this study, various imaging XAFS measurements, including tychographic XAFS, were performed to visualize the chemical state distribution of lithium battery cathode active material particles and the electrode interface during the charge-discharge process. The aim of this study was to extract unknown structure-function correlations related to ion transport and diffusion phenomena within and at particle interfaces. Tychographic XAFS measurements inside spinel-type lithium manganese-nickelate (LNMO) particles have been performed, and the distributions suggesting heterogeneity of Mn and Ni compositions and chemical states within LNMO particles have been successfully captured. In addition, we succeeded in visualizing the internal chemical state of the LNMO particles by conducting measurement experiments on Li-rich vanadium oxide cathode active materials and thin-film all-solid-state battery systems.

Free Research Field

放射光科学

Academic Significance and Societal Importance of the Research Achievements

本研究の成果により、「不均一・複雑な機能性材料系中に潜む埋没した構造－機能相関の発掘する」という課題に対し、「多次元顕微分光測定」、「オペランド計測」、「高度情報処理」を高度に融合させた、材料機能可視化の解析プロトコルをしめすことができた。今後このプロセスをあらゆる機能性材料系に適用することにより、試料の背後に潜んでいる材料機能との未知なる相関性を可視化・定量化し、材料設計へフィードバックしていく可能になることが期待できる。