Preparation of silicon oxide coated KS-6 graphite composite anode materials by sol-gel method in lithium ion batteries

摘要

This work reported a sol-gel preparation method for the SiO2 coated KS-6 composite anode material by using KS-6 graphite, silicon oxide, and glucose (C6H_(12)O6). Silicon oxide was used as a surface modification dopant and C6H_(12)O6 was used as a carbon source. The composite anode material was sintered at 600-700°C in an Ar atmosphere for 5h. The characteristic properties of the composite anode materials were examined by micro-Raman spectroscopy, XRD, SEM, EA and AC impedance method. The coin cell was used to investigate the electrochemical performance at various rates. It was found that the specific discharge capacities of 16wt.%SiO2 coated KS-6 composite anode materials were 404, 422. 323, 192, 67, 29 and 13 mAh g~(-1) at 0.1, 0.2, 0.5, 1, 3, 5 and 10C rate, respectively. However, they all showed the current efficiency of ca. 96-99%. Apparently, the as-synthesized SiO2 coated KS-6 composite anode can be a good candidate for high power Li-ion battery applications.