Composite anode material of silicon/graphite/carbon nanotubes for Li-ion batteries

A composite anode material of silicon/graphite/multi-walled carbon nanotubes (MWNTs) for Li-ion batteries was prepared by ball milling. This composite anode material showed a discharge capacity of 2274 mAh/g in the first cycle, and after 20 charge-discharge cycles, a reversible capacity of 584 mAh/g was retained, much higher than 218 mAh/g for silicon/graphite composite. It was observed that silicon particles were homogeneously embedded into the “lamellar structures” of flaked graphite particles, and the silicon/graphite composite particles were further wrapped by a MWNTs network. The improvement in the electrochemical properties of the composite anode material was mainly attributed to the excellent resiliency and good electric conductivity of the MWNTs network.