Abstract
We prepared Ni-P-coated Si particles by an electroless deposition method as an anode material of a high-performance Li-ion battery, and optimized the interface between electrode and electrolyte by using an ionic liquid electrolyte. For the improvement of an adhesion between Ni-P and Si, we carried out a surface roughening of uncoated Si by a chemical etching, and then a thermal treatment of Ni-P-coated Si particles. Galvanostatic charge-discharge tests were performed for Ni-P-coated Si composite electrodes prepared by a gas-deposition method using the resulting particles. The results showed that an enhanced anode performance was obtained for the electrode of annealed Ni-P/(etched Si) in a conventional organic electrolyte due to the improved adhesion. In addition, the electrode exhibited a significantly stable cyclability in the ionic liquid electrolyte: a high discharge capacity of 1000 mAhg-1 was maintained with no capacity fading for 1100 cycles.