The Influence of Surface Chemistry on the Rate Capability of LiNi[sub 0.5]Mn[sub 0.5]O[sub 2] for Lithium Rechargeable Batteries

Subsequent annealing at 700 ° C enhances the rate capability of LiNi 0.5 Mn 0.5 O 2 , delivering 180 mAh/g at 55 ° C and 8C rate compared to 50 mAh/g of LiNi 0.5 Mn 0.5 O 2 quenched from 1000 ° C . Although Rietvled refinement analyses of X-ray diffraction (XRD) data showed that there were no significant changes in the lattice parameters and cation distributions of the layered structure before and after annealing, XRD and X-ray photoelectron spectroscopy revealed that annealing significantly reduced surface impurity phases such as lithium carbonate and Mn 3 + -containing species. The influence of surface chemistry changes on the rate capability of LiNi 0.5 Mn 0.5 O 2 was discussed.