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A LiFePO4/(C+Fe2P) composite cathode material was prepared by a sol-gel method using Fe(NO3)3·9H2O,LiAc·H2O,NH4H2PO4 and citric acid as raw materials,and the physical properties and electrochemical performance of the composite cathode material were investigated by X-ray diffractometry(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and electrochemical tests.The Fe2P content,morphology and electrochemical performance of LiFePO4/(C+Fe2P) composite depend on the calcination temperature.The optimized LiFePO4/(C+Fe2P) composite is prepared at 650 °C and the optimized composite exhibits sphere-like morphology with porous structure and Fe2P content of about 3.2%(mass fraction).The discharge capacity of the optimized LiFePO4/(C+Fe2P) at 0.1C is 156 and 161 mA·h/g at 25 and 55 °C,respectively,and the corresponding capacity retentions are 96% after 30 cycles;while the capacity at 1C is 142 and 149 mA·h/g at 25 and 55 °C,respectively,and the capacity still remains 135 and 142 mA·h/g after 30 cycles at 25 and 55 °C,respectively.
A LiFePO4 / (C + Fe2P) composite cathode material was prepared by a sol-gel method using Fe (NO3) 3.9H2O, LiAc H2O, NH4H2PO4 and citric acid as raw materials, and the physical properties and electrochemical performance of the composite cathode material were investigated by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical tests. The Fe2P content, morphology and electrochemical performance of LiFePO4 / (C + Fe2P) composite depend on the calcination temperature.The optimized LiFePO4 / (C + Fe2P) composite was prepared at 650 ° C and the optimized composite exhibits a sphere-like morphology with a porous structure and Fe2P content of about 3.2% (mass fraction). The discharge capacity of the optimized LiFePO4 / (C + Fe2P) at 0.1C is 156 and 161 mA · h / g at 25 and 55 ° C, respectively, and the corresponding capacity retentions are 96% after 30 cycles; while capacity at 1C is 142 and 149 mA · h / g at 25 and 55 ° C, respectively, and the capacity still rema ins 135 and 142 mA · h / g after 30 cycles at 25 and 55 ° C, respectively.