Lithium-ion diffusion mechanisms in the battery anode material Li1+xV1−xO2

Abstract

Layered Li_1+xV_1−xO₂ has attracted recent interest as a potential low voltage and high energy density anode material for lithium-ion batteries. A greater understanding of the lithium-ion transport mechanisms is important in optimising such oxide anodes. Here, stoichiometric LiVO₂ and Li-rich Li_1.07V_0.93O₂ are investigated using atomistic modelling techniques. Lithium-ion migration is not found in LiVO₂, which has also previously shown to be resistant to lithium intercalation. Molecular dynamics simulations of lithiated non-stoichiometric Li_1.07+yV_0.93O₂ suggest cooperative interstitial Li⁺ diffusion with favourable migration barriers and diffusion coefficients (D_Li), which are facilitated by the presence of lithium in the transition metal layers; such transport behaviour is important for high rate performance as a battery anode.