Microstructural Evolution in Transition-metal-oxide Cathode Materials for Lithium-Ion Batteries

Layered transition metal oxides are promising materials for high-energy lithium-ion battery cathodes. These materials offer high capacity and rate capability, good safety, and relatively low cost compared to many alternative materials Mixed oxides such as NCA (LiNi 0.8 Co 0.15 Al 0.05 O 2 ) exhibit high capacity but suffer from a significant capacity fade with cycling The composition of alternatives such as NMC (LiNi 1-x-y Mn x Co y O 2 ) can be tuned to show less capacity fade, but generally at the cost of lower capacity. Consequently, there is great interest in cycling these materials to higher potentials for more energy, but then cycling performance decreases.