Synthesis and Electrochemical Performance of Si@void@C Composite Anode Material for Lithium Ion Battery

The Si@void@C composites were prepared by a stober method with Si nanoparticles as the cores. This preparation process involved coating a SiO2 layer through hydrolyzing and self-assembly approach of TEOS, coating a carbon layer through in-situ polymerization and high temperature carbonization of dopamine, and etching SiO2 by HF. Crystalline structure, morphology and electrochemical performances of the composites were characterized by X-ray diffraction, scanning electron microscope, TEM and charge-discharge tests. The results indicate that the Si@void@C anode material retains a charge capacity of 1 319.5 mAh.g(-1) at current density of 0.1 A.g(-1) along with the capacity retention of 78.4% after 100 cycles, and shows an excellent electrochemical performance.