Ni,Cr替代对尖晶石型锰酸锂晶体结构和电化学性能的影响

Influence of Ni,Cr Substitution on Spinel Lithium Manganese Oxides Crystal Structure and Electrochemical Performance

采用共沉淀法,用不同元素(Cr,Ni)对尖晶石型LiMn2O4正极材料中的Mn元素进行替代研究.实验通过X射线衍射(XRD)和扫描电镜(SEM)测试,表征了产物的结构和微观形貌,恒流充放电实验,研究了材料的综合电化学性能.实验结果表明:替代没有改变LiMn2O4的晶体结构,替代后的材料虽然首次充放电容量降低了但其循环性能有较大程度提高,尤其是Cr和Ni同时替代比较明显.

The substitution of Mn by different elements （Cr,Ni）in spinel LiMn2 O4 cathode material is studied by the method of co-precipitation.The XRD,SEM and electrochemistry measurements are used for character-ization and testing the samples.The results show that the substitution does not change the crystal structure of LiMn2 O4 ,although the first charge and discharge capacity decreases but it has a much improved circulation per-formance after the substitution,which is especially obvious with correlative Cr and Ni substitution .