Despite most porous silicon-based anode materials manifest excellent lithium-ions storage properties and have great potential application in the next generation lithium-ion batteries,the scalable and economical synthesis of porous silicon remains a large obstacle to its industrial application.[1] The present work presents the scalable fabrication of porous silicon with high surface area by using cost-effective SiO2 as raw material,through a modified magnesiothermic reduction approach.The result of XRD shows that no side reactions have occurred,and the diffraction peak assigned to amorphous SiO2 is undetectable,both of which demonstrate the high conversion yield of the reaction.In the following rinsing process,the usage of hydrofluoric acid(HF) has been avoided without any sacrifice of property,which is favorable to the large-scale synthesis.Subsequently,a carbon layer with a thickness of 6 nm has been conformally wrapped on the surface of resulting porous silicon through a CVD process,forming Si@C composite.Owing to the nanoscaled size,high surface area and electrical conductivity,the porous Si@C composite exhibits high reversible capacity,durable cycle life and superior rate performance.It is highly expected that the involved methods in this work may have great possibilities to be applied in the production of commercial silicon anode on an industrial scale.