Nano-scale SnO2 powders were prepared by hydrolyzation. Graphite was poured into the SnCl4 solution during hydrolyzation. After drying and calcining at 360℃, the negative electrode composite material of nanosized SnO2 and graphite was obtained. The composite materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The average crystallite size was in the range of 15-20 nm. Electrochemical lithium insertion/extraction was studied preliminarily on the obtained composite. The discharge capacity of nanosized SnO2/graphite composite was found to have a high electrochemical reversible capacity for Li-ion insertion and extraction, which possessed the advantages of both higher discharge capacity of SnO2 and lower discharge potential of graphite. In addition, the cycle capability was also improved due to the inhibiting effect of the composite against pulverization and agglomeration to a certain extent during Li-ion insertion and extraction.
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