[10a-N401-1~9] 7.2 Applications and technologies of electron beams

△ [10a-N401-1] Atomic-resolution STEM analysis of delithiated/pristine interface in Li₂MnO₃

〇Kei Nakayama^1,2, Ryo Ishikawa^1,3, Shunsuke Kobayashi², Naoya Shibata^1,2, Yuichi Ikuhara^1,2 (1.Univ. Tokyo, 2.JFCC, 3.JST PRESTO)

Keywords:STEM, scanning transmission electron microscopy, battery

To understand the delithiation process of Li₂MnO₃, we have investigated the interfacial atomic structure between delithiated and pristine regions in partially delithiated Li₂MnO₃ by scanning transmission electron microscopy. We found that the delithiated regions have extensive amounts of irreversible defects such as oxygen-release. At the delithiated/pristine interface, a number of dislocations are formed at the interface to compensate the lattice mismatch between the pristine and delithiated regions. The observed oxygen-release and dislocations could govern the growth of delithiated regions.