LiFePO_4/C复合材料中的碳源研究  

Carbon source in LiFePO_4/C composite cathode material

作　　者：何文英[1] 胡国荣[1] 彭忠东[1] 杜柯[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《电源技术》2011年第2期158-161,共4页Chinese Journal of Power Sources

基　　金：国家科技支撑计划资助项目(2007BAE12B01-1);湖南省科技计划资助项目(2009GK3150)

摘　　要：分别以蔗糖、酚醛树脂、聚丙烯作为碳源,采用高温固相法制备了橄榄石型锂离子电池正极LiFePO4/C复合材料,并考察不同碳源对合成的LiFePO4/C复合材料电化学性能的影响。采用XRD、SEM、拉曼光谱分析、恒电流充放电测试和交流阻抗分析等方法对材料的结构、表面形貌及电化学性能进行了研究。结果表明,以聚丙烯为碳源合成的LiFePO4/C材料具有最佳的电化学性能。0.1C的放电比容量为154.9mAh/g,在2C下的放电比容量达131.3mAh/g,循环30次后容量为130.1mAh/g。Olivine LiFePO4/C composite cathode materials were synthesized by a solid state method using sucrose,phenolic resin and polypropylene as carbon sources respectively.The effects of different carbon sources on the performance of as-synthesized cathode materials were investigated and analyzed.The crystal structure and the electrochemical performance were characterized by XRD,SEM,Raman spectrum,charge-discharge testing and AC impedance.The results demonstrate that the composite material carbon-coated by polypropylene has the most excellent electrochemical performance which has an initiative capacity of 154.9 mAh/g at 0.1 C and 131.3 mAh/g at 2 C and the capacity is 130.1 mAh/g after 30 cycles at 2 C.

关 键 词：LIFEPO4/C复合材料 碳源 碳包覆 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]