The invention provides preparation and application of a
lithium battery
silicon-carbon
composite material taking synthetic
graphite as a carrier. The preparation method comprises the following steps of: dissolving nanometer
silicon and synthetic
graphite in a dispersant to obtain a uniform dispersion liquid, adding an organic
carbon source, stirring uniformly to obtain a mixed liquid, feeding the mixed liquid into a closed circulation
spray dryer to prepare composite precursor
powder, pre-
sintering for 3-10 hours at the temperature of 300-700 DEG C to obtain a
silicon-carbon
composite material subjected to primary carbon cladding; and further dissolving the silicon-carbon
composite material subjected to primary carbon cladding with the organic
carbon source in a dispersant, stirring to obtain a uniform mixed liquid, feeding the uniform mixed liquid into a second closed circulation
spray dryer to prepare composite
powder, and heating the
powder for 6-18 hours at the temperature of 700-1000 DEG C, so as to obtain the
lithium battery silicon-carbon composite material taking synthetic
graphite as a carrier. The
lithium battery silicon-carbon composite material prepared by the invention shows such excellent electrochemical properties as high first charge-
discharge efficiency, high specific capacity and good cycle performance after being applied to a
lithium battery.