双层碳包覆LiFePO_4合成和电化学性能研究  

Synthesis and electrochemical properties of double carbon coated LiFePO_4

作　　者：黄远提[1] 卢周广[1] 郭忻[1] 胡菁[1] 唐有根[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《电池工业》2012年第1期20-22,27,共4页Chinese Battery Industry

基　　金：国家自然科学基金资助项目(21001117);中南大学仪器共享开放基金项目

摘　　要：采用改进的固相碳热还原法通过两步包碳法制备了双层碳包覆的LiFePO4正极材料。用SEM、XRD等对其进行表征,并将其组装成纽扣式电池,测试了其电化学性能。结果表明通过对前躯体磷酸铁的碳包覆能有效控制产品双层碳包覆磷酸铁锂的颗粒大小,双层碳包覆不改变磷酸铁锂的晶体结构,0.1 C首次放电比容量为150.0 mAh/g,循环50次后比容量仅减少了3.9%。表明所制备的LiFePO4样品具有较好的电化学性能。Double carbon coated LiFePO4 materials were prepared by a simple two-step solid-state carbonthermal method.The samples were characterized by SEM and X-ray diffraction and evaluated as cathode materials for Li-ion battery.Results showed that the carbon layer coated on the FePO4 precursor effectively prevented the crystal growth of LiFePO4 particles in the subsequent calcination process,facilitating particle size control.The samples exhibited a reversible specific capacity of around 150.0 mAh/g at 0.1 C.The capacity retains more than 96% after 50 cycles,indicating superior electrochemical performance.

关 键 词：锂离子电池 正极材料 磷酸铁锂(LiFePO4) 双层碳包覆 碳热还原法 

分 类 号：TM912.9[电气工程—电力电子与电力传动]