Electrochemical and in situ X-ray Absorption Fine Structure Study of Li-Rich Cathode Materials

Authors

Meng-yan HOU, Department of Chemistry, Fudan University, Shanghai, 200433, China;Shanghai Institute of Applied Physics, CAS, Shanghai, 201800;
Hong-liang BAO, Shanghai Institute of Applied Physics, CAS, Shanghai, 201800;
Ke WANG, Department of Chemistry, Fudan University, Shanghai, 200433, China;
Jian-qiang WANG, Shanghai Institute of Applied Physics, CAS, Shanghai, 201800;Follow
Yong-yao XIA, Department of Chemistry, Fudan University, Shanghai, 200433, China;Follow

Corresponding Author

Jian-qiang WANG(wangjianqiang@sinap.ac.cn);
Yong-yao XIA(yyxia@fudan.edu.cn)

Abstract

A series of the lithium-rich and manganese-based layered structure xLi₂MnO₃•(1-x)LiMn_1/3Ni_1/3Co_1/3O₂ (x = 0.3，0.5，0.7) materials were synthesized by a co-precipitation method, and followed by a solid-state reaction process. By comparing the first cycle efficiency, the reversible discharge capacity, the cycling stability and the voltage decay during the charge/discharge cycling process, the material with the composition of 0.5Li₂MnO₃•0.5LiMn_1/3Ni_1/3Co_1/3O₂was found to show the best electrochemical performance. The lithium storage mechanism and thermal stability of the de-lithiated compound were also investigated by in situ X-ray absorption fine structure (XAFS) spectroscopy and differential scanning calorimetry (DSC) techniques. The results of XAFS indicates that during the charging process to 4.5 V, the Ni and Co ions are oxidized to Ni⁴⁺ and Co⁴⁺, respectively, while the Mn ion remains Mn⁴⁺.

Graphical Abstract

Keywords

lithium-rich layered oxides, cathode material, lithium-ion battery, in situ X-ray absorption fine structure

DOI Link

https://doi.org/10.13208/j.electrochem.151248

Publication Date

2016-06-28

Online Available Date

2016-06-02

Revised Date

2016-05-25

Received Date

2016-03-16

Recommended Citation

Meng-yan HOU, Hong-liang BAO, Ke WANG, Jian-qiang WANG, Yong-yao XIA. Electrochemical and in situ X-ray Absorption Fine Structure Study of Li-Rich Cathode Materials[J]. Journal of Electrochemistry, 2016 , 22(3): 288-298.
DOI: 10.13208/j.electrochem.151248
Available at: https://jelectrochem.xmu.edu.cn/journal/vol22/iss3/8