摘要
来用将高分子聚合物(例如酚醛树脂)包覆于石墨表面形成高分子碳化膜的方法,对石墨进行表面修饰处理,大大改善了石墨用作锂离子电池负极的性能。通过电化学测试发现,修饰石墨首次充放电效率达到94.9 %,比容量为306.1mAh/g,并且经过 100次循环后,比容量衰减率仅为 8.2%。通过 SEM观察和XRD衍射分析发现,石墨颗粒表面修饰对颗粒细化,提高锂离子嵌入活性点,防止溶剂分子共嵌入均有增强作用。
We modified graphite by covering the surface with high polymer (e. g. phenolic resin) to form a carbonized film. The modification of graphite surface greatly improved the performance of graphite anode for lithium- ion battery. Electrochemical tests showed that the first charge/discharge efficiency of improved graphite achieved 94. 9%,the specific capacity was 306. 1mAh/g,and decreasing rate of specific capacity was just 8. 3 % after 100 cycles. SEM and XRD results proved that the modification of graphite surface benefited reducing the particle size of graphite. provided more active sites of Li+ intercalation, and prevented the cointercalation of solvent molecule.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2000年第4期436-438,共3页
Journal of Functional Materials