Degradation mechanism of spinel LiAl0.2Mn1.8O4 cathode materials on high temperature cycling

Abstract

The structural degradation of the Al-doped spinel material, LiAl0.2Mn1.8O4, before and after charge-discharge cycling in the 4 V region at elevated temperature has been studied by X-ray diffraction and high-resolution transmission electron microscopy. The capacity loss during cycling was noticeably increased with cell operation temperature from 50 to 80 degreesC. The formation of tetragonal Li(2)Mn2O(4) and the rocksalt phase Li2MnO3 in the spinel electrode cycled at elevated temperature could be responsible for the main cause of the capacity loss.