Industrial waste silica preparation of silicon carbide composites and their applications in lithium-ion battery anode

Silicon particles with uniform sizes were formed by cleaning solid organic wastes from the silicon industry with ether and nitric acid and ball milling the products. The resulting silicon was then used to prepare anode materials for lithium-ion batteries by mixing the silicon with graphite microspheres (GMs) and sintering the mixture in the presence of sucrose. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and thermo-gravimetric analysis were used to characterize the composites. The silicon and GM mixtures contained tightly bound amorphous carbon and ball-like composites. These P-Si/C composites had high capacities (520 mAh/g at 50 mA/g and 320 mAh/g at 500 mA/g) and excellent charge-discharge cycling stabilities, displaying only a 8.8% loss after 100 cycles at 50 mA/g).