Determination of diffusion coefficient of lithium in LiM y Mn2 − y O4 spinels using potentiostatic intermittent titration technique

Abstract

The potentiostatic intermittent titration technique is used to study lithium transport in the LiMyMn2 − yO4 compounds with a spinel structure intended for application as cathodic materials in lithiumion and lithium-polymer batteries. The materials are synthesized using the sol-gel method and the melt-impregnation method. Kinetic and diffusion characteristics of the LixMn2O4 and LixMn1.95Cr0.05O4 compounds are determined at 25°C as dependent on lithium content 0 < x < 1. The diffusion coefficient of lithium varies significantly in the range of 10−10 to 10−13 cm2/s under variation of the electrode composition; the surface resistance depends weakly on the concentration of lithium and is 200–500 Ohm cm2.