Acta Chimica Sinica ›› 2005, Vol. 63 ›› Issue (19): 1853-1856. Previous Articles    

Reports

球形尖晶石LiMn2O4掺杂钇的性能研究

何向明*,蒲薇华,蔡砚,王晓青,姜长印,万春荣   

  1. (清华大学核能与新能源技术研究院材料化学实验室 北京 102201)
  • 投稿日期:2004-01-25 修回日期:2005-07-06 发布日期:2010-12-10
  • 通讯作者: 何向明

Yttrium Doping of Spherical Spinel LiMn2O4 Cathode Materials for Lithium Ion Batteries

HE Xiang-Ming*, PU Wei-Hua, CAI Yan, WANG XIAO-Qing, JIANG Chang-Yin, WAN Chun-Rong   

  1. (Materials Chemistry Laboratory, Institute of Nuclear Energy & New Energy Technology,
    Tsinghua University, Beijing 102201)
  • Received:2004-01-25 Revised:2005-07-06 Published:2010-12-10
  • Contact: HE Xiang-Ming

A controlled crystallization process was proposed for synthesis of yttrium doped spherical spinel LiMn2O4 particles. Its successful preparation started with a carefully controlled crystallization of yttrium doped MnCO3 by co-precipitation of MnSO4 and YCl3 with NH4HCO3 and NH3•H2O. Mn2O3 was obtained by heating MnCO3 and mixed with Li2CO3 to produce yttrium doped spinel LiMn2O4. As-prepared samples were characterized by SEM and XRD. Dissolution of manganese in electrolyte was also investigated, resulting in that the dissolution was enhanced by dopant of yttrium. The more yttrium, the larger dissolution, indicating that manganese was activated by yttrium. The activation of manganese led to both enhancement of electrochemical activity and reactivity with electrolyte of manganese. The former improved the elec-trochemical performance of spinel LiMn2O4. Contrarily, the latter worsened its performance. 0.5% was a proper amount of doping, and such yttrium doped sample Li(Y0.005Mn0.995)2O4 had an initial capacity of 130 mAh•g-1 over that of un-doped one with the capacity retention to reach 92.3% exceeding that of un-doped one at 100th cycle.

Key words: spinel LiMn2O4, doping, yttrium, dissolution of manganese, Li-ion battery