Preparation and electrochemical properties of LiFePO_4/C composite cathodes for lithium-ion batteries

摘要

Three kinds of LiFePO_4/C composites for lithium-ion batteries were prepared by solid-state reaction. The crystalline structure, morphology and specific surface area of the composites were investigated by X-ray diffraction, scanning electron microscopy and multi-point Brunauer, Emmett and Teller. The results showed that the samples were all well-ordered olivine structures. A network structure, LiFePO_4//C composite, was obtained using phenolic resin as carbon source. It possessed the highest specific surface area of 115.65 m~2/g, exhibited the highest discharge capacity of 164-89 and 14912 mAh/g at 0.1 C and 1 C rates, respectively. The discharge capacity was completely recovered when 0.1 C rate was applied again.