The electrochemical stability of spinel electrodes coated with ZrO2, Al2O3, and SiO2 from colloidal suspensions

Stoichiometric LiMn2O4 and substituted Li1.05M0.05Mn1.9O4 (M=Al,Ni) spinel electrodes, coated with ZrO2, Al2O3, and SiO2 from colloidal suspensions, have been evaluated in lithium cells. ZrO2-coated Li1.05Ni0.05Mn1.9O4 electrodes provide the best cycling stability at 50degreesC. The excellent cycling stability is attributed to a porous network of amphoteric ZrO2 Particles, less than 4 nm in dimension, that protect the spinel surface from acid attack by scavenging HF and H2O from the electrolyte, while still allowing access of the electrolyte to the active electrode. (C) 2004 The Electrochemical Society.