Electrochemical characteristics of a-Si thin film anode for Li-ion rechargeable batteries

Deposition of an amorphous Si (a-Si) thin film anode was carried out by a radio-frequency (rf) magnetron sputtering. In order to avoid mechanical disintegration of the Si electrodes, the Si was deposited on two types of Cu foil: normal Cu foil and Cu foil with a rough surface. The surface of the Cu foil was roughened with sandpaper. The properties of Si film were observed by FESEM, Raman, XRD, AFM, CLSM and electrochemical performance was evaluated. It was believed that the rough foil helped the active Si material to maintain the electronic contact with the current collector during charging and discharging.