LiFePO4／Cu复合正极材料的制备及电化学性能

将高温固相法制备的LiFePO4高度分散在含有KNaC4H4O6的CuSO4水溶液中,利用非电解沉积法还原出溶液中的金属Cu,制备出了LiFePO4/Cu复合正极材料。采用XRD、恒流充放电及交流阻抗对材料的晶体结构和电化学性能进行了研究。结果表明:LiFePO4/Cu复合材料保持了橄榄石型LiFePO4的晶体结构,其电化学性能大大优于纯相LiFePO4。0.5C和1.0C倍率下的首次放电比容量分别为118 mAh/g和113 mAh/g,远高于纯相LiFePO4的首次放电比容量,其电荷转移电阻比纯相LiFePO4减少了约26Ω。

Preparation and Electrochemical Performance of LiFePO4/Cu Composite Cathode Material

The LiFePO4 prepared by high temperature solid-state reaction was highly dispersed in CuSO4(aqueous) containing KNaC4H4O6.The LiFePO4/Cu composite was synthesized by an electroless deposition of Cu particles.The crystalline structure and electrochemical performance of the resulting samples were investigated by X-ray diffraction,charge-discharge tests and a.c.impedance techniques.The results show that LiFePO4/Cu composite retains the olive-type phase structure of LiFePO4.The electrochemical performance of the composite is better than that of pure LiFePO4,the initial discharge specific capacities is 118 mAh/g at 0.5C rate and 113 mAh/g at 1.0C rate,which are larger than that of pure LiFePO4.The electric charge transfer resistance of composite is about 26Ω lower than that of pure LiFePO4.