您目前所在的位置:首页 - 期刊简介 - 详细页面

铁道科学与工程学报

JOURNAL OF RAILWAY SCIENCE AND ENGINEERING

Vol. 16    No. 2    April 2006

[PDF Download]    

    

Cyclic voltammetry studies on 4 V and 5 V plateaus of non-stoichiometric spinel Li1+xMn2−yO4
BAI Ying(白 莹)1, 2, WU Chuan(吴 川)1, 2, WU Feng(吴 锋)1, 2, WANG Guo-qing(王国庆)1, 2

1. School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, China;
2. National Development Center for High Technology Green Materials, Beijing 100081, China

Abstract: Li1+xMn2−yO4 spinels with various Li/Mn ratios were synthesized by a solid-state reaction. By X-ray diffraction analysis, Li2MnO3 was detected as a second phase with increasing the Li/Mn ratio; and the role of Li2MnO3 in Li1+xMn2-yO4 spinel was discussed. A slow scanning cyclic voltammetry(CV) at the rate of 0.1 mV/s was adopted to characterize the evolutions of 4 V and 5 V plateaus of Li1+xMn2-yO4 spinels. An additional Li+ insertion in 4 V region was observed in both Li-lack and Li-rich spinels at 3.95 V, which is different from the general Li+ insertion with weak Li-Li interaction and strong Li-Li interaction; and this plateau disappeared in the subsequent cycles. The 4.4 V/3.8 V plateaus correspondent to Li+ insertion and extraction of Li2MnO3 were discussed, and these plateaus have a high reversibility with cycling. The 5 V plateau was found only in the Li-rich samples, and this plateau has a tendency to emerge at higher voltage region with increasing Li/Mn ratio.

 

Key words: lithium manganese oxides; spinel; LiMn2O4; Li2MnO3; cyclic voltammetry

ISSN 1672-7029
CN 43-1423/U

主管:中华人民共和国教育部 主办:中南大学 中国铁道学会 承办:中南大学
湘ICP备09001153号 版权所有:《铁道科学与工程学报》编辑部
------------------------------------------------------------------------------------------
地 址:湖南省长沙市韶山南路22号 邮编:410075
电 话:0731-82655133,82656174   传真:0731-82655133   电子邮箱:jrse@mail.csu.edu.cn