化学学报 ›› 2012, Vol. 70 ›› Issue (06): 812-816.DOI: 10.6023/A1106153 上一篇    

研究论文

天然石墨负极的改性研究

孟祥德a,b, 张俊红a, 王妍妍b, 刘海a   

  1. a 天津大学内燃机燃烧学国家重点实验室 天津 300072;
    b 军事交通学院 天津 300161
  • 投稿日期:2011-06-15 修回日期:2011-11-21 发布日期:2011-11-29
  • 通讯作者: 孟祥德

Modification of Nature Graphite Anode

Meng Xiangdea,b, Zhang Junhonga, Wang Yanyanb, Liu Haia   

  1. a State Key Laboratory of Engines, Tianjin University, Tianjin 300072;
    b Military Transportation University, Tianjin 300161
  • Received:2011-06-15 Revised:2011-11-21 Published:2011-11-29

天然石墨作为锂离子二次电池负极材料得到了广泛关注. 针对天然石墨负极的体积效应和表面活性基团的不利影响, 通过溴化和高温煅烧处理制备石墨插层化合物中间体和适度膨胀的石墨样品以改善其倍率和循环寿命. 样品利用X 射线衍射(XRD)、扫描式电子显微镜(SEM)和比表面积检测(BET)分析其结构特征, 结果表明膨胀石墨样品石墨层剥离晶粒增大. 恒流充放电和循环伏安扫描测试结果表明改性后的石墨样品其倍率性能和循环稳定性均得到明显改善.

关键词: 天然石墨, 负极, 改性, 溴化

Nature graphite, as anode in rechargeable lithium ion battery, has been attracting widely attention. In this paper, aiming to the disadvantage effect of volume and surface active group on the electrochemical performance of nature graphite anode, graphite intercalation compound and expanded graphite were prepared via bromination and calcination to obtain advanced high rate performance and cycle life. The structural characteristics of samples were measured by XRD (X-ray diffraction), SEM (scanning electron microscope) and BET (Brunauer, Emmett and Taylor) techniques. The results show separation of graphitic layers and a larger diameter size of graphitic grain. Constant current charging-discharging and cyclic voltammetry were carried out, indicating the improved high rate performance and cyclic stability of the modified graphite.

Key words: nature graphite, anode, modification, bromination