Amorphous silicon/carbon multilayer thin films as the anode for high rate rechargeable Li-ion batteries

We have synthesized the amorphous silicon/carbon (Si/C) multilayer thin films on Cu substrate and investigated their applications as the anode for high rate rechargeable Li-ion batteries. X-ray diffraction and Raman spectrum revealed that the films were amorphous. The electrochemical evaluation was performed with constant current charge/discharge test under various loading currents in PC. The results showed a high first initial capacity of 3107 mAh g^-1 and a high first coulombic efficiency of 83% at 15C rate (60 A/g). In the following cycles, a capacity of 2000 mAh g^-1 at 30C (120 A/g) and 1500 mAh g^-1 at 60C (240 A/g) were attained with a retention of 99%. The test predicted that the Si/C multilayer thin films were a promising anode material for lithium ion batteries.