Local atomic and electronic structures around Mg and Al dopants inLiNiO2electrodes studied by XANES and ELNES and first-principles calculations

Abstract

We investigated the local atomic and electronic structures around the dopants Mg and Al in a ${\text{LiNiO}}_2$-based cathode material by the combination analysis of their $K$ shell electron energy-loss near-edge structures, x-ray absorption near-edge structures, and first-principles calculations. The occupation sites of the dopants in initial and cycled samples were examined. On the basis of the atomic structures and chemical bonding states of the models whose theoretical spectra were most consistent with the experimental spectra, we discussed the effects of Al and Mg on Li diffusion and their roles in suppressing the degradation of battery properties.