Supercritical-hydrothermal accelerated solid state reaction route for synthesis of LiMn2O4 cathode material for high-power Li-ion batteries
(1. School of Chemical Machinery, Dalian University of Technology, Dalian 116024, China;
2. Center for Green Products and Processing Technologies, Guangzhou HKUST Fok Ying Tung Research Institute,
Guangzhou 511458, China;
3. School of Chemistry and Chemical Engineering, South China University of Technology,
Guangzhou 510640, China;
4. Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology,
Clear Water Bay, Kowloon, Hong Kong, China)
2. Center for Green Products and Processing Technologies, Guangzhou HKUST Fok Ying Tung Research Institute,
Guangzhou 511458, China;
3. School of Chemistry and Chemical Engineering, South China University of Technology,
Guangzhou 510640, China;
4. Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology,
Clear Water Bay, Kowloon, Hong Kong, China)
Abstract: Synthesis of the spinel structure lithium manganese oxide (LiMn2O4) by supercritical hydrothermal (SH) accelerated solid state reaction (SSR) route was studied. The impacts of the reaction pressure, reaction temperature and reaction time of SH route, and the calcination temperature of SSR route on the purity, particle morphology and electrochemical properties of the prepared LiMn2O4 materials were studied. The experimental results show that after 15 min reaction in SH route at 400 °C and 30 MPa, the reaction time of SSR could be significantly decreased, e.g. down to 3 h with the formation temperature of 800 °C, compared with the conventional solid state reaction method. The prepared LiMn2O4 material exhibits good crystallinity, uniform size distribution and good electrochemical performance, and has an initial specific capacity of 120 mA？h/g at a rate of 0.1C (1C=148 mA/g) and a good rate capability at high rates, even up to 50C.
Key words: lithium ion battery; LiMn2O4; supercritical water; solid state reaction; high rate capability