▎ 摘　　要

NOVELTY - Preparation of graphene-based composite material comprises mixing manganese salt solution , hydroxide solution, and solution containing conductive carbon material to obtain mixed slurry, filtering, dispersing in water after washing, and spray-drying to obtain precursor containing manganese and conductive carbon material; adding into high temperature reactor, continuously heating, filling protective gas and and hydrogen, and high temperature reacting; and continuously heating in high temperature reactor, introducing protective gas, introducing second gas containing nitrogen-containing source or carbon source, and depositing to form graphene or nitrogen-doped graphene. USE - The method is used for preparing graphene-based composite material for preparing negative electrode material lithium battery of automobile (claimed). DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of negative electrode material comprising mixing graphene-based composite material with binder and conductive agent and coating on copper foil.