纳米Si粉在高容量锂离子电池负极中的应用研究

通过感应等离子体蒸发凝聚法制备纳米Si粉,以葡萄糖为有机碳源,经高温碳化将纳米Si粉钉扎在石墨载体表面制备出Si/C复合负极材料,采用X射线衍射(XRD)、场发射扫描电子显微镜(0FESEM)和电化学性能测试等对比分析了纳米Si粉、石墨载体和Si/C复合负极材料的结构和性能。结果表明,纳米Si粉作为锂离子电池负极材料首次放电容量和可逆充电容量分别为3 519.4 m Ah/g和2 063.7m Ah/g,但是首次效率只有58.6%,且循环寿命差,Si/C复合负极材料能够有效缓冲纳米Si粉的体积变化,发挥较高的可逆储锂容量,提高循环寿命,但是需进一步改善首次效率。

The application research of nano Si powers in high capacity lithium ion battery cathodeLIU Wen-ping1,2,3,QIN Hai-qing1,2,3, LEI Xiao-xu1,2,3,LIN Feng1,2,3, ZHANG Zhen-jun1,2,3, ZHAO Jun-wei4

The nano Si powers are prepared by radio frequency inductively coupledSplasma evaporation method. Si/C composite cathode materials are prepared through nano Si powersSloading on the surface of the graphite, which is used glucose as organic carbon source by high temperature carbonization. The performance changes of Si powder, graphite carrier and Si/C composite cathode materials areScontrastivelySanalyzed. From electrochemical performance tests,Sit can be found that the firstly discharge capacity and reversible charge capacity of nano Si powers are 3519.4 mAh/g and 2063.7 mAh/g respectively, which are used as lithium ion battery anode materials, butSthe first efficiency is only 58.6% and cycle life is bad. Si/C composite cathode materials can effectively buffer volume change of nano Si powers, which have higher reversible lithium storage capacity and better cycle life, but the first efficiency need to improve.