3D Si@Cu-Ni nano-pillars array composite as carbon/binder free anode for lithium ion battery

In this work, Cu-Ni nano-pillars array (CNPs) with controlled morphology and compositions was synthesized via electro-deposition method as 3D current collector. Si@CNPs electrode was then prepared by magnetic sputtering with Si film thickness of 200»nm and used as the carbon/binder free anode for lithium ion battery. The coulumbic efficiency of Si@CNPs anode was 98 %-99 % after 2 cycles. The discharge capacity of Si@CNPs anode reached to 1766.5»mA»h».»g^-1 and the high capacity retention was 91.6 % after 60 cycles. Furthermore, the reversible capacity of Si@CNPs anode can still remain above 1090»mA»h».»g^-1 at 2 C due to the improved diffusion rate of charge at the solid-liquid two phase interface and the collection efficiency of electrons in current collector, which was higher than that of 2D copper foil supported Si anode (Si@CF).