The Electrochemical Stability of Spinel Electrodes Coated with ZrO[sub 2], Al[sub 2]O[sub 3], and SiO[sub 2] from Colloidal Suspensions

Abstract
Stoichiometric LiMn2O4LiMn2O4 and substituted Li1.05M0.05Mn1.9O4Li1.05M0.05Mn1.9O4 (M=Al,Ni)(M=Al,Ni) spinel electrodes, coated with ZrO2,ZrO2, Al2O3,Al2O3, and SiO2SiO2 from colloidal suspensions, have been evaluated in lithium cells. ZrO2ZrO2 -coated Li1.05Ni0.05Mn1.9O4Li1.05Ni0.05Mn1.9O4 electrodes provide the best cycling stability at 50°C. The excellent cycling stability is attributed to a porous network of amphoteric ZrO2ZrO2 particles, less than 4 nm in dimension, that protect the spinel surface from acid attack by scavenging HF and H2OH2O from the electrolyte, while still allowing access of the electrolyte to the active electrode. © 2004 The Electrochemical Society. All rights reserved.