An effective and simple way to synthesize LiFePO4/C composite

The cathode material is synthesized from FeC2O4·2H2O and LiH2PO4 by a solid-state reaction using citric acid as a carbon source. The electric conductivity of the synthesized LiFePO4 has been raised by eight orders of magnitude from 10−9 S cm−1. The LiFePO4/C composite shows a greatly enhanced rate performance and the cyclic stability at room temperature. It delivers an initial discharge capacity of 128 mAh g−1 at 4C, which is retained as high as 92% after 1000 cycles. In addition, the tested low temperature character is attractive. At −20 °C, the composite exhibits a discharge capacity of 110 mAh g−1 at 0.1C. The homogenous morphology, the porous surface, the small particles inside and the conductive carbon observed contribute much to obtain the favorable electrochemical performance.