Morphology and electrochemical properties of LiMn2O4 powders derived from the sol-gel route

Spinel-lithium manganese oxide (LiMn2O4) powders are prepared by the sol-ge l method using polyvinyl alcohol (PVA) in this study, and evaluated as a po sitive electrode material for Li-ion batteries. PVA helps to maintain the h omogeneity of the system in the precursors and thereby facilitates the form ation of monophasic powders. The average primary particle size of the calci ned LiMn2O4 powders decreases with an increase in the amount of PVA used in solution. Increasing the amount of PVA also results in a rise in the disch arge capacity at 25 degreesC because of the large interface area of small p articles. On the other hand, the discharge capacity of the small LiMn2O4 pa rticles suffers markedly capacity fading when the batteries are operated at elevated temperatures. (C) 2001 Elsevier Science B.V. All rights reserved.