Electron Diffraction Studies of LiNi1/3Mn1/3Co1/3O2 After Charge-Discharge Cycling

Abstract

The performance of LiNi1/3Mn1/3Co1/3O2 depends largely on the distribution of transition-metal (TM) ions over the available lattice sites within the layered rocksalt structure. Despite predictions that the TM ions take on an ordered arrangement described by a sqrt(3)×sqrt(3)R30° supercell, little experimental evidence is available to confirm this model. However, the observed cation distribution likely depends on synthesis conditions. Here, we present a study of commercially produced LiNi1/3Mn1/3Co1/3O2 synthesized at 1000°C before and after charge–discharge cycling. Electron diffraction shows that in-plane ordering is observed to small extents. After charge–discharge cycling, a transformation toward the cubic spinel structure and significant morphology changes are observed.