A Basic Thin Film Study of Spinel Limn204As a Possible Cathode Material for Lithium Secondary Cells

Abstract

ABSTRACTIn a series of fundamental studies on the cathode active materials for a lithium secondary cell using geometrically well-defined sample electrodes, thin films of spinel LiMn204on a platinum plate were investigated in this work in an LiCl04/propylene carbonate solution. These pyrolytically prepared films exihibit reversible extraction/insertion behavior for lithium under galvanostatic charge/discharge cycling between 4.3-3.5 V. The chemical diffusion coefficient of lithium in LixMn204determined by the galvanostatic intermittent titration technique (GITT) was in the order of 10−7-10−10cm2- s−1within a spinel single-phase region of 0.6<x<1.0 and increased with increasingx.