Microemulsion synthesis of LiFePO4/C and its electrochemical properties as cathode materials for lithium-ion cells

The electroactive LiFePO4/C nano-composite powders have been synthesized by a microemulsion method. The material were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopic, scanning electron microscopy and its electrochemical properties were investigated by cyclic voltammetry, AC impedance and charge-discharge tests. The as-prepared LiFePO4/C composite had a high capacity of 163mAhg-1 at the C/10 rate, i.e. 95.9% of the theoretical capacity. The composite also display a good rate capability and stable cycle-life. The improved electrode performance originates mainly from the fine particle of nanometric dimension and the uniform size distribution in the product as well as the increase in electronic conductivity by the carbon coating.