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

Abstract

Layered Li1+xV1-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 Li1.07V0.93O2 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 Li1.07+yV0.93O2 suggest cooperative interstitial Li+ diffusion with favourable migration barriers and diffusion coefficients (DLi), 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. © the Partner Organisations 2014.