金属氧化物掺杂改善LiFePO_4电化学性能  

Electrochemical performance of LiFePO_4 by doping metal oxides

作　　者：唐致远[1] 焦延峰[1] 陈玉红[1] 刘元刚[1] 李昌盛[1] 阳晓霞[1] 

机构地区：[1]天津大学化工学院应用化学系,天津300072

出　　处：《电源技术》2007年第12期951-953,共3页Chinese Journal of Power Sources

基　　金：国家自然科学基金资助项目(No.20273047)

摘　　要：采用氧化物前驱体对磷酸铁锂(LiFePO4)进行少量金属离子掺杂,用X射线衍射、电子扫描显微镜、循环伏安法和恒电流充放电对掺杂的LiFePO4进行了研究。结果表明,少量的掺杂离子在很大程度上提高了LiFePO4的电化学性能,特别是大电流放电性能中1.0%(摩尔分数)的Nb5+掺杂LiFePO4的1C放电比容量约130mAh/g。掺杂后的电化学性能与掺杂离子的半径、价态密切相关,半径合适、价态高的离子对提高LiFePO4的电化学性能有利。Lithium iron phosphate （LiFePO4） containing low concentration ion dopants was prepared by mixing precursors with metal oxides. The LiFePO4 samples were characterized by X-ray diffraction, scanning electron microscope, and electrochemical performance testing. The results indicate that the ion dopants do not affect the structure of the material but considerably improve its electrochemical performance, especially large current discharge behaviors, LiFePO4 samples doped with Nb5＋ have an initiate capacity of 130 mAh/g at 1 C. The results also verify that LiFePO4 doped with ions of suited radius and higher valence shows better electrochemical characters.

关 键 词：磷酸铁锂 金属氧化物 离子掺杂 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]