Substrate effect on the microstructure and electrochemical properties in the deposition of a thin film LiCoO2 electrode

An LiCoO2 thin-film cathode was deposited onto sintered alumina and Si/SiO2 substrates. After annealing at 800 degrees C in O-2 for 30 min, the film d eposited on alumina consisted of large particles with several cracks, where as the film deposited on the Si substrate was composed of very small and un iform particles. The films deposited on Si showed improved electrochemical properties, such as peak potential divergence and rate capability, over tho se for the alumina substrate electrode, which can be attributed to differen ces of the particle size, surface morphology, and the low electrical resist ance of the current collector. (C) 1999 The Electrochemical Society. S1099- 0062(99)06-030-7. All rights reserved.