In Situ determination of the kinetics of reaction between lithium and fast-ion conducting lithium borate glasses

Abstract

A novel electrochemical technique based on coulometric titration in cells of the type: LiAl-Al/Glass/LiA1A1 or LiSnSn was used to determine the chemical stability and kinetics of reaction between Li and lithium borate glass electrolytes. A Li2O.B203 glass was found to be an ideal Li electrolyte over a wide Li activity range (10-17 - 0.06 at 380 °C)2. A chlorine containing glass of nominal composition Li4B7O12Cl was found to react at very low activities of Li (< 10-9) to form a predominantly ionic crystalline reaction layer composed mainly of 3Li2O.B2O3. The rate limiting step in the corrosion process was found to be the electron diffusivity, De. The chemical diffusion coefficient was found to be about 5 × 10-10 cm2/sec at 380°C with an activation energy equal to 0.86 eV. © 1986.