掺锰磷酸铁锂的制备及电化学特性研究  

Preparation of Mn-doped LiFePO_4 and Studies on Its Electrochemical Behavior

作　　者：张静[1] 叶一斌[1] 赖恒[1] 

机构地区：[1]福建师范大学物理与能源学院,福建福州350117

出　　处：《福建师范大学学报（自然科学版）》2013年第1期53-57,共5页Journal of Fujian Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(11074032;11074039)

摘　　要：通过一种简易的制备方法,以三价的氢氧化铁为铁源,乙酸锰为锰源,蔗糖为还原剂和碳源,制备掺锰的磷酸铁锰锂(LiFe0.9Mn0.1PO4/C)复合材料.通过X射线衍射、扫描电子显微镜(SEM)表征掺杂锰对磷酸铁锂的结构和表面形貌的影响,同时通过不同倍率充放电测试、交流阻抗分析、循环伏安法测定等研究LiFe0.9Mn0.1PO4/C电化学特性变化.实验表明:(1)掺杂少量Mn2+对LiFePO4橄榄石型结构没有明显影响;(2)LiFe0.9Mn0.1PO4/C与纯相的LiFePO4/C相比,具有充放电比容量更大、电化学可逆性更好、结构更稳定、导电性能更优异等优点.This paper concentrates on the preparation of the LiFe0.9Mn0. 1 PO4/C through a simple method, with the Fe （OH）3 as iron source, the CgH6MnO4·4H2O as manganese source and the C12H22011 as reducing agent and carbon sources. The influence of doped manganese on the structure and morphological performances of the LiFe0.9Mn0. 1PO4/C composites were characterized by X- ray diffraction （XRD） and scanning electron microscopy （SEM）. At the same time, we also investigated the change of electrochemical characterization of the LiFe0.9Mn0. 1PO4/C through charge/discharge experiments at different rate, electrochemical impedance spectroscopy （EIS） and cyclic voltammetry. Result shows that： （1） The obvious change of the structure of LiFePO4 olivine-type is not observed with a small amount of doped Mn2＋ ; （2） Compared with LiFePO4, the main advantages of the LiFeo.9 Mno. 1 P04/C are larger charging and discharging capacity, better electrochemical reversibility, better structure stability, and more excellent conductivity performance, etc.

关 键 词：锂离子电池 正极材料 磷酸铁锰锂 碳热还原法 电化学特性 掺杂 

分 类 号：O469[理学—凝聚态物理]