锂离子蓄电池碳负极材料的嵌锂动力学研究  

Kinetic behaviors of carbon anode materials for Li-ion battery

作　　者：张万红[1,2] 岳敏 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471003 [2]河南省有色金属材料科学与加工技术重点实验室,河南洛阳471003 [3]深圳市贝特瑞新能源材料股份有限公司,广东深圳518055

出　　处：《电源技术》2010年第5期431-434,共4页Chinese Journal of Power Sources

基　　金：河南科技大学博士基金项目(09001232)

摘　　要：采用恒电位阶跃法研究了各种碳(石墨)电极的动力学性能,测定了锂离子在电极中扩散系数。结果表明,随着电极嵌锂程度的增加,锂离子在其中的固相扩散系数增大。锂离子在结晶度较好的球形天然石墨和改性天然石墨中的扩散系数较大,而对非晶态的软炭和硬炭,锂离子在其中的扩散系数稍低,轴定向结构的碳纤维材料具有最低的锂离子扩散系数。锂离子在负极材料中的固相扩散过程主要受材料晶体结构、结晶度、微晶晶界及缺陷数量等的影响,结晶度低、晶界及晶体缺陷阻碍作用强的碳材料,锂离子在其中的扩散系数较小。The kinetic behaviors of several kinds of carbon electrode were studied by means of potential step chronoamperometric method, and the chemical diffusion coefficients （D） of Li ions in carbon electrodes was determined. It is found that D increases with Li intercalating into carbon （graphite）. Crystallized natural graphite spheres and modified natural graphite have increased D, the amorphous soft carbon and hard carbon has smaller D, and graphitic carbon fiber GCF with axis-directional structure has the lowest D. The chemical diffusion coefficient （D） of Li ions depends mainly on the structure, graphitization degree, the amount of grain boundary and defect of carbon anode particles, and etc. D decreases with the enhanced impeditive action of the grain boundary and defect for amorphous carbon.

关 键 词：碳负极 锂离子蓄电池 锂离子扩散系数 动力学 

分 类 号：TM912.9[电气工程—电力电子与电力传动]