Preparation and electrochemical performance of 2LiFe_(1-x)Co_xPO_4-Li_3V_2(PO_4)_3/C cathode material for lithium-ion batteries  

2LiFe_(1-x)Co_xPO_4-Li_3V_2(PO_4)_3/C锂离子电池正极材料的制备和性能(英文)

作　　者：张佳峰[1] 张宝[1] 郭学益[1] 欧星[1] 王健龙[1] 彭春丽[1] 郑俊超[1] 陈核章[1] 沈超[1] 

机构地区：[1]中南大学冶金科学与工程学院,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第4期1028-1032,共5页中国有色金属学报（英文版）

基　　金：Project(51072233) supported by National Natural Science Foundation of China

摘　　要：2LiFe1-xCoxPO4-Li3V2（P04）3/C was synthesized using Fel-2xCo2xVO4 as precursor which was prepared by a simple co-precipitation method. 2LiFej-xCoxPO4-Li3V2（PO4）3/C samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical measurements. All 2LiFel-xCoxPOa-Li3V2（PO4）3/C composites are of the similar crystal structure. The XRD analysis and SEM images show that 2LiFe0.96Co0.04PO4-Li3V2（PO4）3/C sample has the best-ordered structure and the smallest particle size. The charge-discharge tests demonstrate that these powders have the best electrochemical properties with an initial discharge capacity of 144.1 mA.h/g and capacity retention of 95.6% after 100 cycles when cycled at a current density of 0.1C between 2.5 and 4.5 V.用共沉淀法合成的Fe_(1-2x)Co_(2x)VO_4为原料制备2LiFe_(1-x)Co_xPO_4-Li_3V_2(PO_4)_3/C。采用X射线衍射、扫描电镜以及电化学测试对2LiFe_(1-x)Co_xPO_4-Li_3V_2(PO_4)_3/C样品进行表征。结果表明,所有2LiFe_(1-x)Co_xPO_4-Li_3V_2(PO_4)_3/C复合材料样品均有相似的晶体结构。X射线衍射和扫描电镜表明,2LiFe_(0.96)Co_(0.04)PO_4-Li_3V_2(PO_4)_3/C具有最有序的晶体结构和细小、均匀的颗粒。充放电测试表明,2LiFe_(0.96)Co_(0.04)PO_4-Li_3V_2(PO_4)_3/C具有最佳的电化学性能,在电压2.5～4.5 V,0.1C条件下首次放电比容量可达144.1 mA·h/g,循环100次后容量保持率仍可达到95.6%。

关 键 词：LIFEPO4 Li3V2（PO4）3 Co doping lithium-ion batteries 

分 类 号：TM912[电气工程—电力电子与电力传动]