Novel synthesis of LiFePO4 by aqueous precipitation and carbothermal reduction

LiFePO4 is prepared by aqueous precipitation of FePO4·2H2O from FeSO4·7H2O and NH4H2PO4 with hydrogen peroxide as the oxidizing agent, following carbothermal reduction with carbon as the reducer. Samples were characterized by XRD and SEM. It was showed that pure and homogenous LiFePO4 was successfully obtained below 600 °C. The size of the material synthesized at 560 °C for12 h is about 0.1–0.3 μm. Residual carbon during processing was coated on LiFePO4, resulting in the enhancement of the material's electronic properties. Electrochemical measurements show that the material synthesized at 560 °C for 12 h has a best electrochemical performance and its discharge capacity is about 152 mAh g−1 at 0.1 C rate and 129 mAh g−1 at 1 C rate with satisfactory capacity retention.