银的添加方式对LiFePO_4性能的影响  

Effects of Silver-adding Methods on the Performance of LiFePO_4

作　　者：张露露[1] 杨学林[1] 游敏[1] 张鹏昌[1] 

机构地区：[1]三峡大学机械与材料学院,宜昌443002

出　　处：《材料导报》2009年第6期42-45,共4页Materials Reports

基　　金：国家自然科学基金项目(50672114);湖北省教育厅科学技术研究计划重点项目(D20081304);宜昌市科技攻关项目(A08303-04);三峡大学科学基金项目(ZJX200608)

摘　　要：以化学镀(ELP)和真空热分解(VTD)工艺制得了LiFePO4/Ag复合材料,采用X射线衍射、扫描电镜对样品进行了表征,同时对样品进行了交流阻抗、循环伏安和恒流充放电等电化学性能测试。结果表明,与纯LiFe-PO4相比,复合材料的首次不可逆容量有所降低,比容量增加。真空热分解所制得的银颗粒更小且分布更均匀。该复合材料在0.2C下首次放电容量为143.1mAh/g,库仑效率为90.6%;在1C下循环30次后仍能释放出116.6mAh/g的可逆容量。LiFePO4/Ag composites with 2wt% of silver are prepared by electroless plating（ELP） and vacuum thermal decomposition（VTD）. X-ray diffraction（XRD） and scanning electron microscopy （SEM）are used to detect the phases presented in the composites and observe the samples morphology. In addition, AC electrochemical impedance spectroscopy（EIS）, cyclic voltammetry（CV）, along with constant current discharge/charge tests,are used to characterize the electrochemical properties of the composites. It is shown that the composites could deliver less irreversible capacity and higher specific capacity, compared with the pure LiFePO4. VTD-prepared LiFePO4/Ag, with silver particles （〈1μm） highly dispersed on the surface of LiFePO4 particles, delivers the first discharge capacity of 143. 1mAh/g with the coloumbic efficiency of 90. 6% at 0. 2C, and keeps a reversible capacity of 116. 6mAh/g after 30 cycles at 1.0C.

关 键 词：LIFEPO4 银 化学镀 真空热分解 

分 类 号：TM912.9[电气工程—电力电子与电力传动]