Multicomponent olivine cathode for lithium rechargeable batteries: A first-principles study

The in-depth study of the multicomponent effect on the structural and electrochemical properties of olivine cathodes is conducted using state-of-the-art first-principles calculations. The distribution of multiple transition metals in olivine structure alters local crystal structure and electronic structure, affecting its kinetic and thermodynamic properties. We find that local structure change, such as the reduced Jahn-Teller effect of Mn, significantly enhances both Li mobility and electron (polaron) conductivity when the redox Mn element neighbors Fe or Co. The unexpected one-phase Li insertion/ extraction reaction of the multicomponent olivine cathode is explained with respect to the multiple interactions of M/Li or M/vacancy (M = transition metals). The redox potential of each transition metal also could shift as a result of charge redistribution and the relative energy change from the multiple M/Li interactions. Implications of multicomponent olivine as a useful strategy for tailoring the electrochemical properties of olivine compounds are discussed for designing better-performing Li rechargeable batteries.