Abstract:Nano-silicon particles and vapor-grown carbon fiber composites (Si/VGCF) were prepared by liquid phase mixing method in order to improve the conductivity and cycling stability of the silicon anode of lithium ion batteries. The preparation conditions of the Si/VGCF, the optimum content of VGCF were investigated. The morphology and crystal structure of the Si/VGCF materials were characterized using Scanning Electron Microscopy and Transmission Electron Microscopy. The electrical conductivity, BET specific surface area and pore size of the Si/VGCF composites were tested and calculated. The electrochemical properties of Si/VGCF electrodes were tested by using cyclic voltammetry, galvanostatic charge-discharge and alternating current impedance methods. The results indicate that the hierarchical network structure formed by Si and VGCF has abundant ions and electrons conductive channels. Also, the structure with the rich pores can alleviates the volume effect of Si particles during the processes of the intercalation/deintercalation of Li , which significantly improves the utilization and electrochemical stability of the electrode active materials. When m(Si):m(VGCF) is 1:0.5, the Si/VGCF electrode delivers a reversible capacity of 1470 mAh?g-1 at a current density of 500 mA?g-1 after 100 cycles.