Acta Chimica Sinica ›› 2011, Vol. 69 ›› Issue (02): 117-121.     Next Articles

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改性Pechini方法合成富锂正极材料Li[Li(1/3-x/3)CoxMn(2/3-2x/3)]O2及性能研究

赵煜娟*,赵春松,孙召琴,冯海兰   

  1. (北京工业大学环境与能源工程学院 北京 100124)
  • 收稿日期:2010-07-23 修回日期:2010-09-06 出版日期:2011-01-28 发布日期:2010-09-19
  • 通讯作者: 赵煜娟 E-mail:zhaoyujuan@bjut.edu.cn

Synthesis and Characterization of Li-rich Cathode Materials Li[Li(1/3-x/3)CoxMn(2/3-2x/3)]O2 by Modified Pechini Method

ZHAO Yu-Juan, ZHAO Chun-Song, SUN Zhao-Qin, FENG Hai-Lan   

  1. (College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124)
  • Received:2010-07-23 Revised:2010-09-06 Online:2011-01-28 Published:2010-09-19

The Li-rich cathode materials Li[CoxLi(1/3-x/3)Mn(2/3-2x/3)]O2 with different Co contents (x=0.4, 0.5, 0.6) were synthesized by modified Pechini method. The results of XRD confirmed that the crystals of the Li-rich compounds possess layered structure and have good crystallinity. The initial discharge capacities of the compounds are high between 200~220 mAh/g, increasing with the increase of Co contents. The material with x=0.4 exhibits the best cycling property. The capacity retainment is about 75% after 50 cycles at 0.5 C (100 mA/g). The peak of Mn4+/Mn3+occurred below 3.5 V in the plots of dQ/dV, and the area of the peak increases with the cycle numbers. The results of the XRD during the cycling process show the layer structure of the Li-rich materials transfers to the spinel phase, and the impurities appears during the cycling, resulting in the capacity fade.

Key words: lithium ion batterie, Li-rich cathode material, modified Pechini method, electrochemical behaviors