Molecular Dynamics Study on Ion Diffusion in LiFePO4 Olivine Materials

Molecular dynamics (MD) simulations have been employed to investigate the ionic diffusion and the structure of LiFePO4 cathode material. The results correspond well with the published experimental observations. The simulation results indicated that the diffusion of lithium ions was thermally activated and more significant than those of other ions. Compared with other cathode materials, the shifts of ions were less significant in LiFePO4. This suggested that LiFePO4 was more thermally stable. The snapshots of the positions of lithium atoms over a range of the steps provided a microscopic picture and the picture showed the lithium ions migrated through one-dimension channels.