Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (3): 467-475.doi: 10.3866/PKU.WHXB201312252

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Crystal Structure and Electrochemical Performance of Lithium-Rich Cathode Materials xLi2MnO3·(1-x)LiNi0.5Mn0.5O2 (x=0.1-0.8)

CHEN Lai1, CHEN Shi1,2, HU Dao-Zhong3, SU Yue-Feng1,2, LI Wei-Kang1, WANG Zhao1, BAO Li-Ying1,2, WU Feng1,2   

  1. 1 Beijing Key Laboratory of Environmental Science and Engineering, School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing 100081, P. R. China;
    2 National Development Center of Hi-Tech Green Materials, Beijing 100081, P. R. China;
    3 China North Vehicle Research Institute, Beijing 100072, P. R. China
  • Received:2013-10-24 Revised:2013-12-20 Published:2014-02-27
  • Contact: SU Yue-Feng E-mail:suyuefeng@bit.edu.cn
  • Supported by:

    The project was supported by the National Key Basic Research Program of China (973) (2009CB220100), National Natural Science Foundation of China (51102018, 21103011), National High Technology Research and Development Program of China (863) (2011AA11A235, SQ2010AA1123116001) and Beijing Institute of Technology Scientific and Technological Innovation Project, China (2013CX01003).

Abstract:

A series of lithium-rich cathode materials, xLi2MnO3·(1-x)LiNi0.5Mn0.5O2 (x=0.1-0.8), were successfully synthesized by a sol-gel method. X-ray diffraction, scanning electron microscopy, and electrochemical tests were used to investigate the crystal structure, morphology, and electrochemical performance of the as-synthesized materials, respectively. The results showed that the materials with higher Li2MnO3 content had higher initial discharge capacity but poorer cycle stability, while the materials with lower Li2MnO3 content showed lower discharge capacity but better cycle stability, and the spinel impurity phase was also found. Based on the data, the optimal electrochemical properties were obtained when x=0.5 in xLi2MnO3·(1-x)LiNi0.5Mn0.5O2. Moreover, the electrochemical properties were also worthy of attention when x=0.4, 0.6.

Key words: Lithium-ion battery, Cathode, Li2MnO3, Crystal structure, Electrochemical performance

MSC2000: 

  • O646