Silicon nanowire array films as advanced anode materials for lithium-ion batteries

Silicon nanowire array films were prepared by metal catalytic etching method and applied as anode materials for rechargeable lithium-ion batteries. The films completely consisted of silicon nanowires that were single crystals. Aluminum films were plated on the backs of the silicon nanowire films and then annealed in an argon atmosphere to improve electronic contact and conduction. In addition to easy preparation and low cost, the silicon nanowire film electrodes exhibited large lithium storage capacity and good cycling performance. The first discharge and charge capacities were 3653 mAh g−1 and 2409 mAh g−1, respectively, at a rate of 150 mA g−1 between 2 and 0.02 V. A stable reversible capacity of about 1000 mAh g−1 was maintained after 30 cycles. The good properties were ascribed to the silicon nanowires which better accommodated the large volume change during lithium-ion intercalation and de-intercalation.