锂离子电池用Si/针状焦复合负极材料的改性及其电化学性能  

Modification and Electrochemical Performance of Si/Needle Coke as Anode Material for Lithium Ion Batteries

作　　者：叶冉[1] 成果[1] 詹亮[1] 张秀云[2] 刘春法[2] 梁晓怿[1] 乔文明[1] 凌立成[1] 

机构地区：[1]华东理工大学,化学工程联合国家重点实验室,上海200237 [2]上海宝钢化工有限公司,上海201900

出　　处：《材料科学与工程学报》2010年第1期44-48,共5页Journal of Materials Science and Engineering

基　　金：国家863重点资助项目(2008AA062302);国家自然科学基金资助项目(20806024,50672025,5073003);中国博士点基金资助项目(20070251008);上海市国际合作资助项目(08160704000);上海市大学生创新计划资助项目(yx0237102-07)

摘　　要：以石墨化针状焦为原料,采用机械球磨和化学气相沉积法（CVD）制得碳/Si/针状焦复合负极材料。结合XRD、SEM分析手段和电化学特征,研究发现：当石墨化针状焦复合20%的纳米Si后,其首次放电容量高达1110mAh/g,但25次循环后放电容量衰减为200mAh/g;采用CVD方法,在Si/针状焦复合材料的表面沉积厚度为6~8nm的碳后,其首次库伦效率为81%,25次循环后放电容量仍能稳定在860mAh/g,且循环效率接近99%。Carbon/Si/needle coke composite anode material was prepared from graphitized needle coke by using ball-milling and chemical vapor deposition （CVD） method.According to the analysis of XRD,SEM and relative electrochemical performances,the first discharge capacity of Si/needle coke composite electrode obtained 1110mAh/g if nano Si was added with a weight ratio of 20%,but the discharge capacity reduced to 200mAh/g after 25 cycles.When the carbon was deposited on the surface of Si/needle coke composite with a thickness of 6～8nm by CVD,the first coulomb efficiency was 81% and the discharge capacity can still remain at 860mAh/g even if it was charge/discharged for 25 cycles.

关 键 词：锂离子电池 针状焦 纳米SI 化学气相沉积 

分 类 号：TB34[一般工业技术—材料科学与工程]