Physical and Electrochemical Properties of a Mixed Lithium Phosphate as Cathode Material for Lithium Ion Battery

Abstract

A mixed lithium phosphate LiMn0.6Fe0.4PO4 as cathode material for lithium ion battery was synthesized by solid-state reaction. The crystalline structure, morphology of particles and electrochemical performances of the sample were investigated by X-ray diffraction, scanning electron microscopy, charge-discharge test and cyclic voltammetry. The results show that the small LiMn0.6Fe0.4PO4 particles are simple pure olive-type phase structure with uniformly distribution of gain size. The LiMn0.6Fe0.4PO4 obtained has a high electrochemical capacity, good cycle ability and excellent stability under high temperature. However, the capacity loss corresponding to 4.0V plateau at high rate, which had been proved by various electrochemical tests, is the main obstacle to its practical application.