(83g) Silicon Li-Ion Anode Materials Via Spray Drying and Magnesiothemic Reduction

We report an effective and scalable method to produce silicon (Si) and silicon-carbon (Si-C) composite with the combination of spray drying, magnesiothermic reduction and chemical vapor deposition. Commercial silica water suspension (LUDOX HS-40) is used as the Si precursor. Diluted silica (SiO₂) suspension is spray-dried with an aerosol spray dryer. Subsequent magnesiothermic reduction of the spray-dried SiO₂, with sodium chloride as the heat scavenger, is performed to convert SiO₂ to Si with retention of the secondary composite structure. After coating a thin layer of carbon via chemical vapor deposition, the Si-C composites as Li-ion battery anode materials show excellent cycle stability of 1400 mAh/g for 100 cycles.