Performances of lithium manganese oxide prepared by hydrothermal process

KONG Long(孔龙)^{1, 2}, LI Yun-jiao(李运姣)^{1, 2}, ZHANG Peng(张鹏)³, HUANG Hai-hua(黄海花)³, YE Wang-qi(叶万奇)¹, LI Chun-xia(李春霞)^{1, 2}

(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Citic Dameng Mining Industries Limited, Nanning 530028, China;
3. Changsha Research Institute of Mining and Metallurgy Corporation Limited, Changsha 410083, China)

Abstract:A simple hydrothermal process followed by heat treatment was applied to the preparation of spinel Li_1.05Mn_1.95O₄. In this process, electrolytic manganese dioxide (EMD) and LiOH·H₂O were used as starting materials. The physiochemical properties of the synthesized samples were investigated by thermogravimetry-differential scanning calorimetry (TG-DSC), X-ray diffractometry (XRD), and scanning electronic microscopy (SEM). The results show that the hydrothermally synthesized precursor is an essential amorphous. The precursor can be easily transferred to spinel powders with a homogeneous structure and a regularly-shaped morphology by heat treatment. Li_1.05Mn_1.95O₄ powder obtained by heat treating the precursor at 430 °C for 12 h and then calcining at 800 °C for 12 h shows an excellent cycling performance with an initial charge capacity of 118.2 mA？h·g^-1 obtained at 0.5C rate and 93.8% of its original value retained after 100 cycles.

Key words:lithium ion batteries; LiMn₂O₄; hydrothermal method; heat treatment