Grinding sol gel synthesis and electrochemical performance of mesoporous Li_3V_2(PO_4)_3 cathode materials  

介孔Li_3V_2(PO_4)_3正极材料的研磨溶胶凝胶法合成和电化学性能(英文)

作　　者：刘国聪[1,2] 刘又年[1] 刘素琴[1] 

机构地区：[1]中南大学化学化工学院,长沙410083 [2]惠州学院化学工程系,惠州516007

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第2期439-444,共6页中国有色金属学报（英文版）

基　　金：Project (51162026) supported by the National Natural Science Foundation of China;Projects (20100480949, 201104509) supported by China Postdoctoral Science Foundation;Project (133274341015501) supported by Postdoctoral Science Foundation of Central South University, China

摘　　要：Li3V2（PO4）3 precursor was obtained with V2Os.nH2O , LiOH＇H2O, NH4H2PO4 and sucrose as starting materials by grinding-sol-gel method, and then the monoclinic-typed Li3Vz（PO4）3 cathode material was prepared by sintering the amorphous Li3V2（PO4）3. The as-sintered samples were investigated by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, N2 adsorption-desorption and electrochemical measurement. It is found that Li3Vz（PO4）3 sintered at 700 ℃ possesses good wormhole-like mesoporous structure with the largest specific surface area of 188 cmZ/g, and the smallest pore size of 9.3 nm. Electrochemical test reveals that the initial discharge capacity of the 700 ℃ sintered sample is 155.9 mA.h/g at the rate of 0.2C, and the capacity retains 154 mA.h/g after 50 cycles, exhibiting a stable discharge capacity at room temperature.以V2O5·nH2O、LiOH·H2O、NH4H2PO4和蔗糖为原料,采用研磨溶胶凝胶技术制备了无定形Li3V2(PO4)3前驱体,再经过焙烧获得具有单斜结构的介孔Li3V2(PO4)3正极材料,并用XRD、SEM、TEM、比表面积和电化学性能测试来表征材料的性能。研究表明,在700°C下焙烧的样品具有良好的介孔结构、最大的比表面积(188cm2/g)和最小的孔径(9.3nm)。在0.2C倍率下,该介孔样品的首次放电容量达155.9mA·h/g,经过50次循环后其容量仍然可达154mA·h/g,表现出非常稳定的放电性能。

关 键 词：Li3Vz（PO4）3 cathode material mesoporous structure grinding-sol-gel method electrochemical performance 

分 类 号：TM912[电气工程—电力电子与电力传动]