Preparation of Particles of Electroactive Transition Metal Compounds

点击翻译按钮获取中文摘要

The olivine-type compound LiMnPO_4 was prepared via a reaction between Li_3PO_4 and a MnSO_4 aqueous solution under hydrothermal conditions at 190℃. The specific surface area and particle morphology of LiMnPO_4 changed depending on the amount of water in the reaction mixtures, and the particle size decreased as the amount of water decreased. It was found that nanosized LiMnPO_4 particles of ca. 50nm can be prepared through the reaction between Li_3PO_4 and the molten aqua-complex of MnSO_4・nH_2O (n=4 or5). Galvanostatic charge and discharge tests revealed that the electrochemical reactivity of LiMnPO_4 at 30℃ increased as the particle size decreased. The small particle size contributes to the decrease in the overpotential for Mn^<2+/3+> redox and to the increase in the utilization of LiMnPO_4 as an active material in the cathode of lithium batteries.