Enhancement of capacity of carbon-coated Si-Cu3Si composite anode using metal-organic compound for lithium-ion batteries

A carbon-coated Si-Cu3Si composite material is prepared using silicon and copper(II) D-gluconate powders by simple mechanical milling and pyrolysis, and is investigated as an anode material for lithium-ion batteries. In this process, the Cu3Si and pyrolyzed carbon uniformly adhere to the surface of the silicon particles. The cycling performance of the composite material exhibits a stable capacity of 850 mAh g(-1) for 30 cycles. The improved cycling performance is attributed to the fact that the copper silicide and pyrolyzed carbon provide both a better electrical contact with the current-collector and a buffering effect for the volume expansion-contraction during cycling. (c) 2006 Elsevier B.V. All rights reserved.