磷酸铁锂掺杂改性中Li位和Fe位掺杂效果分析  

The doped effect analysis of lithium iron phosphate at Li and Fe sites

作　　者：张俊喜[1] 许明玉[1] 曹小卫 宋锴焱[1] 梅颖[1] 严锦程[1] 杨希[1] 王保峰[1] 

机构地区：[1]上海电力学院电化学研究室,上海200090 [2]上海奥威科技开发有限公司,上海201203

出　　处：《功能材料》2011年第S4期699-702,共4页Journal of Functional Materials

基　　金：上海市科委能力建设资助项目(09230501400);教育部科技研究重点资助项目(205055);中国航天科工集团支撑技术基金资助项目(DL01-2004);上海市教委科研创新资助项目(09Y2338);上海市教委优秀青年教师资助项目(SDL08011)

摘　　要：对LiFePO4的不同位金属离子掺杂改性进行了研究,采用共沉淀法合成Li位和Fe位Mg2+、Mo6+掺杂的LiFePO4正极材料,通过XRD、XPS、充放电曲线以及CV、Mott-Schottky对材料进行表征和测试,主要分析了金属离子在Li位和Fe位掺杂对材料性能的影响。结果表明Mg2+和Mo6+可以分别在Fe位和Li位掺杂,且不会影响磷酸铁锂的橄榄石结构,掺杂可以改善材料的电化学性能。从掺杂效果来看,Fe位掺杂比Li位掺杂更优越,从材料的晶体结构和半导体性质着手对掺杂机理作了分析讨论。The modification of metal ion doping at different sites in LiFePO4 was investigated in this paper.Co-precipitation method was used to synthesize LiFePO4 positive materials doped with Mg2+,Mo6+ at Fe site and Li site. The characteristic and performance of synthesized material were studied by using XRD,XPS,cyclic voltammetry,charge-discharge curve.Results showed that Mg2+ and Mo6+ ions can be doped in Fe site and Li site of LiFePO4,and the doping will not affect its olivine structure.The electrochemical property and charge-discharge performance of materials were obviously improved whatever site doped in,and the material doped in Fe site is better than that in Li site.The doping mechanism was discussed based on crystal structure and semiconductor theory.

关 键 词：LIFEPO4 掺杂 Li位 Fe位 Mott-Schott-ky测试 

分 类 号：TM912[电气工程—电力电子与电力传动]