Graphene/silicon nanocomposite anode with enhanced electrochemical stability for lithium-ion battery applications

Composite anodes, prepared with high-molecular weight polyacrylic acid as green binder, exhibited high and stable reversible capacity values, of the order of 1000 mAh g−1, when cycled using vinylene carbonate as electrolyte additive. After 100 cycles at a current of 500 mA g−1, the anode showed a discharge capacity retention of about 80%. The mechanism of reversible lithium uptake is described in terms of Li-Si alloying/dealloying reaction. Comparison of the impedance responses of cells tested in electrolytes with or without vinylene carbonate confirms the beneficial effects of the additive in stabilizing the composite anode.