Novel design of uniform Si@graphite@C composite as high-performance Li-ion battery anodes

We design a novel Si@graphite@C composite via the pretreatment of graphite, subsequent deposition of Si nanoparticles via chemical vapor deposition, and finally the coating of carbon layer. The enlarged macropores of graphite can accommodate more loading of Si nanoparticles and the use of monosilane gas as source can bring the uniform deposition of Si nanoparticles in the whole graphite microparticles. The Si@graphite@C composite has good electrical conductivity and can well accommodate the volume change during the charge/discharge process, thus result in a good electrochemical performance. The relationship between pore size distribution, Si particles distribution and electrode performance is also investigated.