REDUCED GRAPHENE OXIDE-GRAPHITE COMPOSITE MATERIAL, METHOD FOR PRODUCING SAME, AND LITHIUM ION SECONDARY BATTERY USING SAME

An object of the present invention is to provide a reduced graphene oxide-graphite composite material capable of improving battery characteristics such as the charge and discharge efficiency and the capacity retention ratio of a lithium ion secondary battery, and a method for producing the same. The present invention relates to a reduced graphene oxide-graphite composite material in which a reduced graphene oxide and a graphite are formed into a composite, wherein the functional group ratio (C—O/C═O) between C—O bond and CO=bond is 3 to 6 as obtained from a C1s spectrum based on surface analysis measured by X-ray photoelectron spectroscopy (XPS).