Study on Li ion diffusion in LixV2O5 using first principle calculations and kinetic Monte Carlo simulations

We study the Li diffusion in LixV2O5 (0 < x <= 1)-a potential cathode material for Lithium ion batteries. Different diffusion pathways in this material with dependence on the Li ion concentration are investigated by applying first-principles calculations. The results are used to obtain the corresponding diffusion coefficients by employing two complementary methodologies: Kinetic Monte Carlo (KMC) simulations and a statistical thermodynamics approach. The KMC simulations for two different crystal planes give new evidence that the diffusion occurs mainly along the [010] direction, while the corresponding diffusion coefficients show a temperature dependence obeying Arrhenius' Law. The necessity of the consideration of concentration-dependent barrier heights in the KMC simulations are demonstrated by looking at the significant changes of the concentration-dependence of the diffusion coefficients. The simulated diffusion coefficients of the combined approach show a good quantitative agreement with experimental data reported previously.

Automated summary

Li diffusion in LixV2O5 was studied using first-principles calculations. Different diffusion pathways were investigated, and the diffusion coefficients were obtained using Kinetic Monte Carlo simulations and statistical thermodynamics. The simulations showed that diffusion mainly occurs along the [010] direction, and the diffusion coefficients follow Arrhenius' Law. The consideration of concentration-dependent barrier heights in the simulations was demonstrated to be necessary by observing significant changes in the concentration-dependence of the diffusion coefficients. The simulated diffusion coefficients were in good agreement with experimental data.