摘要
石墨作为锂离子电池的负极材料具有高的脱嵌锂容量及平坦且低的（相对于锂金属）电压特性，但也存在一些问题，如在高倍率充放电性能及与电解质的相容性方面。本工作制备并研究了环氧树脂包覆石墨制备的复合碳材料。当用这种复合碳材料作为锂离子电池的负极时，它的无序结构的焦炭壳层防止了石墨核心材料在插锂过程中的剥落现象，改进了锂离子在阳极材料中的扩散性能。这种材料与石墨相比，不仅保留了石墨具有较高的插锂容量的特性，并且大大改进了其与电解质溶液的相容性和动力学性能，当这种复合碳材料用１Ｃ充放电时，仍保持有２００ｍＡｈ／ｇ的容量。
Graphite used as anode for lithium ion battery has high reversible lithium intercalate/deintercalate capacity and a flat voltage curve near zero volts vs. lithium. However, there are some problems such as slow lithium ion diffusion rate and poor compatibility with electrolyte solutions. In this work, a coke/graphite composite with core shell structure has been manufactured. The disordered coke shell will protect the graphite core from exfoliation and improve the diffusion rate of lithium ions into anode. The anode material with our developed core/shell composite carbon has high capacity of lithium intercalation, excellent kinetics and good compatibility with electrolyte solutions in comparison with naked graphite anode. The intercalate lithium capacity of coke/graphite composite remains 200mAh/g at 1C charge/discharge.
出处
《电源技术》
CAS
CSCD
北大核心
1999年第1期7-9,25,共4页
Chinese Journal of Power Sources
