Synthesis, electrochemical properties, and characterization of LiFePO4/C composite by a two-source method

LiFePO4/C composites were synthesized by a solid state reaction method utilizing two-component mixture of FeC2O4.2H2O and LiH2PO4. Sintering the reactants with C12H22O11 at different temperatures above 650 deg. C yields a product containing Fe2P as a secondary phase to olivine LiFePO4. The LiFePO4/Fe2P/C composite synthesized at 750 deg. C exhibits an excellent electrochemical performance, i.e. a discharge capacity of 152 mAh/g with a smooth plateau of 3.37 V and a good cycle performance at 0.2C charge/discharge current rate. Other detection techniques, such as X-ray absorption near edge structure (XANES) and scanning electron microscopy (SEM), were also carried out to characterize the sample.