Polyoxovanadate(NH_4)_7[MnV_(13)O_(38)] as cathode material for lithium ion battery and improved electrochemical performance  

锂离子电池用聚氧钒酸盐正极材料及其电化学性能改善（英文）

作　　者：李文良[1,2] 倪尔福 李新海[1] 郭华军[1] 

机构地区：[1]中南大学冶金与环境学院,长沙410083 [2]豪鹏国际集团,深圳518111

出　　处：《Transactions of Nonferrous Metals Society of China》2016年第9期2372-2379,共8页中国有色金属学报（英文版）

摘　　要：The polyoxovanadate（NH4）7[MnV13O38]（AMV） was synthesized and characterized by X-ray diffraction pattern, Fourier transform infrared spectra, and field emission scanning electron microscope equipped with energy dispersive X-ray spectroscopy. In order to improve the electrochemical performance of AMV, the particle size of as-prepared AMV is decreased to nanoscale by re-precipitation in the water-ethanol solution. The results of the electrochemical impedance spectra and the 4-pin probe measurements show that the electrical conductivity of AMV is improved by decreasing the particle size. The nanoparticle AMV shows higher initial discharge capacity and energy density than the as-prepared AMV when cycled at 0.5C. On the other hand, the nanoparticle AMV exhibits higher rate capability than the as-prepared AMV.合成了聚氧钒酸盐(NH_4)_7[MnV_(13)O_(38)](AMV),并采用X射线衍射、傅里叶变换红外光谱及配有能量分布X射线谱的场发射电子扫描显微镜对AMV进行了表征。为了改善AMV的电化学性能,通过在水-乙醇溶剂中再结晶将制备的AMV粒子尺寸降低到纳米级。电化学阻抗谱及4-探针测试结果表明,通过降低粒径尺寸可以提高AMV的电导率。在0.5C下进行充放电循环时,纳米颗粒AMV比制备的AMV表现出更高的初始放电容量及能量密度。另外,纳米颗粒AMV比制备的AMV表现出更高的倍率性能。

关 键 词：lithium ion battery cathode material POLYOXOVANADATE NANOPARTICLE 

分 类 号：TM912[电气工程—电力电子与电力传动]