Microstructure and electrochemical properties of magnetron-sputtered LiCoO2/LiNiO2 multi-layer thin film electrode

LiCoO2 single-layer and LiCoO2/LiNiO2 multi-layer thin film electrodes were successfully fabricated by magnetron sputtering. Their microstructure and electrochemical properties were investigated. Once annealed, both films had the (0 0 3) preferred orientation to minimize the surface energy. The initial discharge capacity of the multi-layer thin film was approximately 53.1 μAh/cm2 μm, which was higher than that of the LiCoO2 single-layer thin film having similar thickness. The capacity retention of the multi-layer thin film was superior to that of the single-layer thin film. These findings indicate that the multi-layer thin film is a promising cathode material for the fabrication of high-performance thin film batteries.