Imaging of Li distribution in Li-ion batteries by Particle-Induced Gamma Ray Emission using proton microbeam

陽子線マイクロビームを用いた粒子線誘起線放出分析によるリチウムイオン電池におけるリチウム分布の画像化

三間 圀興*; 東 博純*; 山崎 明義; 神谷 富裕; 奥田 匠昭*; 右京 良雄*; 加藤 義章* ; Gonzales, R.*; Soldo, F.*; Perlado, J. M.*; 西村 博明*; 中井 貞夫*

Mima, Kunioki*; Azuma, Hirozumi*; Yamazaki, Akiyoshi; Kamiya, Tomihiro; Okuda, Chikaaki*; Ukyo, Yoshio*; Kato, Yoshiaki*; Gonzales, R.*; Soldo, F.*; Perlado, J. M.*; Nishimura, Hiroaki*; Nakai, Sadao*

The micro-meter scale distribution of Li in a positive electrode of a Li-ion battery contains LiNiCoAlMgO (x = 1.050.5) micro particles was imaged by micro-PIGE (Particle-Induced Gamma Ray Emission) technique with the beam diameter of 11.5 m at Takasaki Ion Accelerators for Advanced Radiation Application facility. In the experiments, measurements were made on the cross section of a positive electrode which was disassembled from the Li-ion battery after rapid charging. As a result, we found that the Li concentration distribution is non-uniform along the depth direction as is expected from the Li diffusion velocity and the charging speed of the sample. This results show that the IBMA is a powerful tool for the diagnostics of the Li-ion batteries and also for that of other battery structures under various charge and discharge conditions. Those data are expected to be useful for the R&D of the advanced batteries.