Solid State Reaction Preparation of LiFePO_4/(C+Cu) Cathode Material and Its Electrochemical Performance

作     者：Yanhong Yin Xiangnan Li Xinxin Mao Xianliang Ding Shuting Yang 

作者机构：School of Chemistry and Chemical EngineeringHenan Normal University Engineering Technology Research Center of Motive Power and Key Materials of Henan Province 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2013年第29卷第10期

页      面：937-942页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：the Henan Province Foundation and Advanced Technology Research Program (No.102300410256) the Key Scientifc and Technological Project of Henan Province (No.102102210183) the Natural Science Research Project of Henan Province (No.2011B480005) 

主　　题：LiFePO4/(C + Cu) Cu-coated Low temperature performance Li-ion batteries Electrochemical performances Materials synthesis 

摘      要：Cu-C co-coated LiFePO4 （LiFePO4/（C ＋ Cu）） cathode material was successfully prepared through solid state reduction reaction. The optimized additive amount of CuO was determined by electrochemical test of series content-dependent samples. Electrochemical performances of LiFePO4/（C ＋ Cu） cathode material were investigated. Crystalline structure, morphology and electrochemical performance of the samples were characterized by X-ray diffraction, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, energy dispersive spectroscopy （EDS）, charge-discharge tests and AC impedance techniques. Results showed that crystal structure of the bulk material was not destroyed after Cu particles distributed on the surface of LiFePO4/C. With 5 wt% CuO additive, the LiFePO4/（C ＋ Cu） cathode material showed improved electrochemical performance especially at high rates and low temperature. At 25 ℃ and 0.1 C current rate, specific capacity of the Cu-coated sample reaches 161.3 mA h/g. The result was 47 mA h/g higher than that of the un-coated one. At -20 ℃, the discharge capacity of Cu-coated materials was 113.4 mA h/g at 0.1 C rate and 83.8 mA h/g at 5 C rate, which reached about 70% of that at room temperature, respectively.