In-situ dilatometric study of Metal/Si multilayer film electrodes

Silicon film and Metal/Si multilayer films of three different metals, Ti, Al and Zn, were prepared via magnetron sputtering. The electrochemical performance of these films was investigated, with a focus on the Li+ intercalation behaviour, using Auger electron spectroscopy and in-situ electrochemical dilatometry. Comparative studies of silicon film electrodes and Metal/Si multilayer film electrodes were also made. The results of in-situ electrochemical dilatometry indicate that Metal/Si multilayer film electrodes expand significantly less than silicon film electrodes when a similar amount of lithium ions are intercalated. Among films with a similar, sandwich-like structure, Ti/Si films exhibit the least volume expansion; whereas those composed of Al/Si films expand the most. Moreover, the expansion rates of multilayer film electrodes are slower than silicon film electrodes.