First-principles study of LiMPO₄ compounds (M=Mn, Fe, Co, Ni) as electrode material for lithium batteries

Abstract

The intercalation voltages of cathode materials for rechargeable lithium-ion batteries are calculated for lithium-orthophosphate oxides LiMPO₄ (M=Mn, Fe, Co and Ni) using density-functional theory within the local-density (LDA) and LDA + U approximations. We show that the LDA + U approximation is able to reproduce the experimental volumes as well as the experimentally observed magnetic structures of the lithiated and non-lithiated compounds for which LDA qualitatively fail. Moreover, we find that, using the LDA + U approach, the experimental evolution of the lithium intercalation voltage along the series can be reproduced accurately.

Acknowledgements

We acknowledge Laboratoire de Physique et Modélisation des Milieux Condensés for computational resources on the PC cluster PHYNUM (CIMENT, Grenoble).