镁离子掺杂对LiFePO_4材料性能的影响  

Influence of Mg Ion Doping on Performance of LiFePO_4

作　　者：胡成林[1] 代建清[1] 戴永年[1] 易惠华[1] 

机构地区：[1]昆明理工大学材料与冶金工程学院

出　　处：《昆明理工大学学报（理工版）》2007年第2期26-29,共4页Journal of Kunming University of Science and Technology(Natural Science Edition)

基　　金：云南省自然科学基金(项目编号:2004E0009Q)

摘　　要：为了提高LiFePO4的电化学性能,用Mg2+对LiFePO4进行掺杂,以Li3PO4为锂源、Mg(OH)2为掺杂源,采用固相法合成锂离子电池正极材料Li1-xMgxFePO4(x=0.005、0.01、0.02和0.03).通过X射线衍射分析及电化学测试,研究了Mg掺杂对材料的结构和电化学性能的影响.实验研究表明,掺入少量的Mg2+,可以减小晶胞体积,提高LiFePO4的循环性能和比容量.当Mg的掺入量为2 mol%时,以0.1C倍率充放电,Li0.98Mg0.02FePO4最大放电容量为123.6 mAh/g.In order to improve the performance of LiFePO4, Li1-xMg, FePO4 （x =0. 005,0. 01,0. 02 and 0. 03） with Mg^2＋ dopant is prepared by solid state reaction using Li3PO4 as Lithium precursor and Mg（ OH）2 as dopant source. The influence of Mg^2＋ dopant on the structure and electrochemical performance of Li1-xMgxFePO4 material is investigated by X -ray diffraction and electrochemical tests. It is shown that low concentration Mg^2＋ dopant can decrease the lattice volume and increase the capacity and cycle performances of LiFePO4. When the dopant concentration of Mg^2＋ is 2 mol%, the maximum discharge capacity of Li0.gsMgo.02FePO4 is 123.6 mAh/g at 0. 1 C charge-diseharge rates.

关 键 词：锂离子电池 LIFEPO4 镁离子 

分 类 号：TM912[电气工程—电力电子与电力传动]