Crystal structure and size effects on the performance of Li[Ni1/3Co1/3Mn1/3]O2 cathodes

We have investigated the effects of crystal structure and size of Li[Ni1/3Co1/3Mn1/3]O-2 (L333) cathodes on the performance of lithium-ion batteries. Cation ordering and particle sizes were determined as a function of annealing temperature with subsequent electrochemical performance monitored by cyclic voltammetry (CV) and charge-discharge testing. With increasing annealing temperature, L333 exhibits a greater cation ordering, which subsequently benefitted cell performance. However, higher annealing temperatures yielded larger crystal sizes, which resulted in a decrease in high rate discharge capacity and a significant capacity fade. This is attributed to an increase in lattice parameter and volume expansion during cycling, with the largest crystal sizes displaying the most significant structural changes due to the lower strain accommodation.