表相掺杂Co的球形LiMn_2O_4制备及其电化学性能

Preparation and electrochemical properties of spherical LiMn_2O_4 surface doped with cobalt

通过CoSO4与LiOH溶液的沉淀反应,在球形Mn2O3前驱体表面包覆Co(OH)2,再与Li2CO3混合后于750℃下高温烧结20h,得到表相掺杂Co的尖晶石锰酸锂正极材料。SEM和XRD结果表明,合成样品为球形,表面粗糙,属于单一的立方晶系尖晶石结构,无其它杂相产生。与纯相LiMn2O4相比,表相掺杂Co的正极材料在室温和55℃时的循环比容量和电化学性能均得到一定提高。

Co（OH）2 was precipitated on the surface of spherical precursor Mn2O3 with the reaction of COSO4 and LiOH solutions. Then it mixed with Li2CO3, and sintered at 750℃ for 20 hours to produce spinel LiMn2O4 cathode material with surface cobalt doping. The results of SEM and XRD showed that the sample was spheroid with coarse surface and a uniform cubic spinel structure. No other impurities are contained. Compared with un-doped LiMn2O4 cathode, the Codoped one showed a higher specific capacities and a better cycling performance at room temperature and 55℃.