LiCoO2的形貌与结构对其电化学性能的影响
来源期刊:中南大学学报(自然科学版)2004年第2期
论文作者:彭文杰 李新海 王云燕 王志兴 郭华军
文章页码:222 - 227
关键词:锂离子电池;正极材料; LiCoO2;形貌结构;电化学性能
Key words:lithium ion battery; cathode material; LiCoO2; morphology and structure; electrochemical performance
摘 要:研究了对电极界面状态有重要影响的LiCoO2物理参数如粒径分布、比表面积及表面形貌等对LiCoO2电化学性能的影响。研究结果表明:粒径及比表面积对LiCoO2电极的容量循环稳定性及电压循环稳定性有较大的影响;适宜的粒径分布有助于提高LiCoO2电极的循环稳定性,过大的比表面积会使电极循环稳定性急剧下降;随着晶块尺寸的减小,LiCoO2材料在大电流下的放电性能得到改善;在优化条件下合成的LiCoO2样品具有最佳的高倍率性能、较高的容量及电压循环稳定性。
Abstract: The influence of physical parameters, such as particle distribution, specific surface area and morphology, which play an important role on the electrochemical behavior of LiCoO2 was investigated. The results show that the particle size and specific surface area have a great effect on the stability of capacity and voltage cycling performance of LiCoO2. A narrow particle size distribution is favorable for the improvement of cycling performance of LiCoO2, while too large specific surface area can sharply deteriorate its performance. With the decrease of the crystal size, the charge/discharge performance in heavy drain is improved. Under the optimum conditions, the synthesized LiCoO2 shows excellent high rate performance, high capacity and stable voltage performance.