锂离子电池正极材料LiFe_(1-2x)Mn_xMg_xPO_4/C的电化学性能研究  

Electrochemical properties of LiFe_(1-2x)Mn_xMg_xPO_4/C cathode material as lithium ion batteries

作　　者：康彩荣[1,2] 莫祥银[1] 丁毅[2] 陆春华[2] 许仲梓[2] 沈健[1] 

机构地区：[1]南京师范大学分析测试中心&江苏省生物功能材料重点实验室,江苏南京210097 [2]南京工业大学材料科学与工程学院,江苏南京210009

出　　处：《功能材料》2010年第2期208-210,共3页Journal of Functional Materials

基　　金：国家重点基础研究发展计划(973计划)资助项目(6134501ZT01-004-02);江苏省自然科学基金资助项目(2005CCA004;BK2007600);德意志学术交流基金资助项目(DAAD Section 423-China;Monglia);南京师范大学教育部留学回国人员科研启动基金资助项目(2006191XLH0132)

摘　　要：通过高温固相合成法以MnCO3为锰源、(MgCO3)4·Mg(OH)·5H2O为镁源,葡萄糖为碳源,在氩气气氛下合成二元掺杂Mn、Mg的LiFe0.8Mn0.1Mg0.1PO4/C和LiFePO4/C正极材料,采用X射线衍射(XRD)、扫描电子显微镜(SEM)、红外光谱仪(FT-IR)进行结构表征,通过恒电流充放电实验研究了LiFe0.8Mn0.1Mg0.1PO4/C和LiFePO4/C电化学性能。结果表明,二元掺杂Mn、Mg的LiFe0.8Mn0.1Mg0.1PO4/C呈现橄榄石结构,无杂质产生。与未掺杂的LiFePO4/C相比,掺杂后LiFe0.8Mn0.1Mg0.1PO4/C提高了电导率,0.1C倍率下放电可逆容量为131mAh/g,表现出良好的电化学性能。LiFe0.8Mn0.1Mg0.1PO4/C and LiFePO4/C were respectively prepared using MnCO3 and（MgCO3）4·Mg（OH）2·5H2O,glucose as doping starting materials by high-temperature solid state reaction under Ar atmosphere.The prepared composites were characterized by X-ray diffraction,scanning electron microscope and FT-IR spectroscopic,and electrochemical performance was investigated with constant current charge-discharge experiment.The results showed that LiFe0.8Mn0.1Mg0.1PO4/C preserved olivine structure with no impurity.Compared with LiFePO4/C,the electronic conductivity of LiFe0.8Mn0.1Mg0.1PO4/C has been improved.LiFe0.8Mn0.1Mg0.1PO4/C had a reversible capacity of 131mAh/g at 0.1C discharge rate,and showed good electrochemical properties.

关 键 词：锂离子电池 正极材料 磷酸铁锂 离子掺杂 

分 类 号：TQ912[化学工程]