Preparation and electrochemical properties of high-performance LiFePO4

Carbon covered LiFePO4 powders with the microstructure of submicro-particles aggregated 5.01wt% carbon content, and the diameter of aggregated particle of 10 mu m were synthesized by solid state sintering processing. The capacity and cycle performance were studied at the charge and discharge rate of C/10, C/5, C/2 and 1C. The results show that below the rate of C/2, the voltage platform and capacity is not sensitive to the rate. When the rate is increased to 1C, the capacity is decreased and the voltage platform is increased in charge processing and decreased in discharge processing. Along with the increasing of cycle number, the capacity is increased to its saturate value. After 30 cycles, the capacities are 131.7, 129.1, 123.5 and 114.4 mAh/g, respectively.