Nanocomposite electrode materials for high energy density rechargeable lithium batteries
The manganese and chromium oxide nanocomposite electrode materials were synthesized by redox reactions using transition metal powders in solutions. The layered LiCrxLi(1/3-x/3)Mn(2/3-2x/3)O2 (x=0.054, 0.0142, 0.147 and 0.311) materials having α-NaFeO2 (R-3m) structure were prepared by solid-state reactions with LiOH and the pre-prepared manganese and chromium precursors. The amount of chromium, after removing the traces of Li2CrO4 from the prepared samples, is found to increase with temperature. The LiCrxLi(1/3-x/3)Mn(2/3-2x/3)O2 material with x=0.147 exhibits a high discharge capacity of 280mAhg-1 in the first cycle and a good reversible capacity of about 250mAhg-1 when cycled in the voltage range 2.0-4.9V. Whereas, the LiCrxLi(1/3-x/3)Mn(2/3-2x/3)O2 material with x=0.311 delivers a very low initial discharge capacity of 98mAhg-1, which is found to be increased up to a discharge capacity of about 260mAhg-1 at the 30th cycling. This drastic increase in capacity is attributed to the redox couples of Cr+4/Cr+6 and Cr+3/Cr+4.
S J Kim S H Kim D H Kim J S Im H Y Ahn J W Kang E J Kim J Kim
Department of Materials Science and Engineering, Chonnam National University 300, Yongbongdong, Bukgu, Gwangju 500-757, South Korea
国际会议
第二届功能原料国际研讨会(The 2rd International Symposium on Functional Materials)
杭州
英文
57-61
2007-05-16（万方平台首次上网日期，不代表论文的发表时间）