Silicon-carbon composite dispersed in a carbon paper substrate for solid polymer lithium-ion batteries

摘要

Carbon coated silicon (Si/C) dispersed in a carbon paper (CP) was examined as the anode for solid polymer lithium-ion batteries. The CP was prepared by pyrolysis of poly(acrylonitrile) fiber and Manila hemp non-woven cloth at 2600 ℃ under an inert atmosphere. The Si/C composite was formed by pyrolysis of a slurry consisting of Si power and a solution of polyvinyl chloride in tetrahydrofuran as the carbon source. Si/C:CP with a weight ratio of 20:100 had a high initial capacity of 980 mAh g~(-1) of Si/C and a high initial columbic efficiency of 77%, and also exhibited excellent capacity retention with a reversible capacity of 710 mAh g~(-1) of Si/C even after 250 cycles at a charge and discharge rate of 0.1 A g~(-1) The carbon fiber framework in the carbon paper could adsorb the volume change of Si during the lithium insertion and stripping processes.