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 deposited on alumina consisted of large particles with several cracks, whereas the film deposited on the Si substrate was composed of very small and uniform particles. The films deposited on Si showed improved electrochemical properties, such as peak potential divergence and rate capability, over those for the alumina substrate electrode, which can be attributed to differences of the particle size, surface morphology, and the low electrical resistance of the current collector. (C) 1999 The Electrochemical Society. S1099-0062(99)06-030-7. All rights reserved.