锂离子电池用Sn-MCMB复合材料碳热还原合成的研究

Study on Sn-MCMB composite materials prepared by carbon-thermal reduction as negative electrode for Li-ion batteries

用碳热还原法制备了Sn-MCMB复合材料，通过XRD、SEM、恒流充放电循环和慢速扫描循环伏安（CV）等方法对其电化学嵌脱锂性能做了研究。结果表明：SnO2被MCMB还原成金属Sn圆球颗粒，吸附在McMB上的球径平均尺寸为500nm，而未吸附的为15μm，均匀分散在MCMB微球之间。该材料的首次嵌脱锂比容量分别可以达到892和657mAh／g，库仑效率为73％，循环14周以后的脱锂比容量为366mAh／g。

Sn-MCMB composite materials were prepared by carbon-thermal reduction method from SnO2 and MCMB in Ar atmosphere. The materials were characterized by XRD and SEM. Electrochemical lithium insertion/emersion character of the materials was determined by constant current charge-discharge and slow scan cyclic voltammetry methods（CV）. The results of XRD and SEM show that SnO2 are reduced to Sn with spherical shape. The initial lithium insertion/ emersion special capacity of the materials can reach to 892mAh/g and 657 respectively and initial coulombic efficiency is 73%. Even after fourteenth cycle, Sn-MCMB composite materials show high emersion special capacity as 366mAh/g.