High performance SiOC composites as the anode material for lithium-ion batteries synthesized by ball milling

摘要

To overcome the problem of volume change of SiO anode material, SiO/C composites are synthesized with different proportion of SiO and citric acid by ball milling and pyrolysis. The electrochemical performance and microstructure of the composites are investigated by XRD, SEM and Land. The composite anode material shows a discharge capacity of 1768 mAh/g in the first cycle with the coulombic efficiency of 62%. After 50 cycles, the discharge capacity is about 540 mAh/g. The improved stability of the materials can be attributed to the carbon-coating formed during pyrolysis progress, which effectively buffer the volume expansion of SiO and improve the conductivity of the composites.