物理化学学报 >> 2009, Vol. 25 >> Issue (08): 1490-1494.doi: 10.3866/PKU.WHXB20090901

研究论文 上一篇    下一篇

锂离子电池正极材料LiV3-xMnxO8的水热合成与性能

冯季军, 刘祥哲, 刘晓贞, 姜建壮, 赵静   

  1. 济南大学化学化工学院, 济南 250022|山东大学化学化工学院, 济南 250100
  • 收稿日期:2009-03-31 修回日期:2009-06-15 发布日期:2009-07-16
  • 通讯作者: 冯季军 E-mail:chm_fengjj@ujn.edu.cn

Hydrothermal Syntheses and Properties of LiV3-xMnxO8 as Cathode Materials for Lithium Ion Batteries

FENG Ji-Jun, LIU Xiang-Zhe, LIU Xiao-Zhen, JIANG Jian-Zhuang, ZHAO Jing   

  1. School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China|School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
  • Received:2009-03-31 Revised:2009-06-15 Published:2009-07-16
  • Contact: FENG Ji-Jun E-mail:chm_fengjj@ujn.edu.cn

摘要:

采用水热法制备了Mn掺杂改性的锂二次电池钒基层状正极材料LiV3-xMnxO8(x=0.00, 0.01, 0.02, 0.04, 0.06, 0.08, 0.10). 用X射线衍射(XRD)和扫描电镜(SEM)对材料的晶体结构和形貌进行表征, 并以50 mA·g-1的电流对材料进行恒流充放电测试. 研究了Mn掺杂对材料晶体结构和电化学性能的影响. 结果表明, Mn掺杂能够明显改善材料的电化学性能. 在掺杂改性的LiV3-xMnxO8材料中, LiV2.94Mn0.06O8的初始容量最高, 达到295 mAh·g-1. 当掺杂量控制在0.01≤x≤0.08范围内时, LiV3-xMnxO8材料均具有较好的循环性能和充放电可逆性, 经20次循环后放电比容量都保持在120 mAh·g-1以上, 40次循环后都保持在100 mAh·g-1以上, 且材料的充放电效率始终维持在93%以上.

关键词: 锂离子电池, 正极材料, 水热合成, 钒酸锂, 锰掺杂

Abstract:

The Mn modified lithiated vanadium oxides LiV3-xMnxO8 (x=0.00, 0.01, 0.02, 0.04, 0.06, 0.08, 0.10) as promising cathode materials for secondary lithium batteries were prepared using a hydrothermal method. Crystalline phases were characterized by powder X-ray diffraction (XRD) and the morphology was observed by scanning electron microscopy (SEM). The electrochemical properties of the synthesized samples were investigated by galvanostatic charge and discharge at a current density of 50 mA·g-1. The effects of manganese doping on crystal stability were analyzed in terms of the material structure and electrochemical performance. The electrochemical properties were greatly improved after manganese doping. Among the doping modified materials, LiV2.94Mn0.06O8 showed the highest initial specific discharge capacity which was 295 mAh·g-1. Good cycle performance was achieved when 0.01≤x≤0.08. All the LiV3-xMnxO8 (0.01≤x≤0.08) materials maintained the specific discharge capacities of more than 120 mAh·g-1 after 20 cycles and 100 mAh·g-1 after 40 cycles thereby preserving the high charge-discharge efficiencies of no less than 93%.

Key words: Lithiumion battery, Cathode material, Hydrothermal synthesis, Lithiumtrivanadate, Mn doping

MSC2000: 

  • O646