Electron Diffraction Studies of LiNi_(1/3)Mn_(1/3)Co_(1/3)O_2 After Charge–Discharge Cycling

The performance of LiNi_(1/3)Mn_(1/3)Co_(1/3)O_2 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 √3 X √3R30° 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 LiNi_(1/3)Mn_(1/3)Co_(1/3)O_2 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.