沥青基人造石墨/天然石墨球复合炭负极材料的制备与性能  

Preparation and properties of pitch-based artificial graphite/natural spherical graphite composites anode material

作　　者：甘雷[1] 郭华军[1] 李新海[1] 王志兴[1] 胡启阳[1] 黄思林[1] 

机构地区：[1]中南大学冶金与环境学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2014年第1期33-39,共7页Journal of Central South University:Science and Technology

基　　金：湖南省科技计划重大专项(2011FJ1005);中央高校基本科研业务费重大项目(2010QZZD0101)

摘　　要：将沥青与天然石墨球按不同比例混合,经碳化处理后再进行石墨化得到锂离子电池用复合炭负极材料。研究结果表明:复合炭材料具有较大的平均层间距d002;复合炭材料仍保持类球形形貌;复合炭材料在较大倍率下的循环性能优于天然石墨球,其中在沥青基人造石墨与天然石墨球的质量比为15%的条件下,0.1C(1C=300 mA/g)充放电电流下材料的可逆比容量为343.7 mA·h/g,首次库仑效率为85.4%,1C下可逆比容量为295.4 mA·h/g,达到0.1C时可逆比容量的85.9%;1C倍率下50次循环比容量保持率为91.6%,与天然石墨球相比,复合材料具有更大的锂离子扩散系数。Pitch-based artificial graphite/natural spherical graphite composites with various mass ratios were obtained by carbonizing and graphitizing the mixtures of pitch and natural spherical graphite. The results show that the prepared composites still have spherical morphology. Larger interlayer spacing exists in the prepared composites, which results in better cyclic performance of the composites at a higher rate than that of natural spherical graphite. When the mass ratio of pitch-based artificial graphite and natural spherical graphite is 15%, the reversible specific capacity is 343.7 mA·h/g at 0.1C （1C=300 mA/g）, while its initial coulombic efficiency is 85.4%. And its reversible specific capacity at 1C is 295.4 mA.h/g, which is 85.9% of that at 0.1C. The capacity keeps 91.6% even after 50 cycles at 1C. Compared to natural spherical graphite, it has a larger lithium ion diffusion coefficient.

关 键 词：锂离子电池 沥青 复合 人造石墨 天然石墨 

分 类 号：TM912.9[电气工程—电力电子与电力传动]