▎ 摘　　要

NOVELTY - Preparing graphene/carbon nanotube composite material comprises adding 0.5-5 l deionized water into graphite oxide to obtain 0.5-2 mg/ml graphite oxide solution, ultrasonically processing the solution, adding 0.05-5 g carbon nanotube, ultrasonically processing continuously, adding 0.125-7.5 l ethylene glycol to obtain a liquid mixture, heating, filtering and drying. USE - The composite material is useful as electrode active material in electrochemical capacitor (claimed). ADVANTAGE - The composite material: has low agglomeration rate of graphene sheet; and has high energy storage capacity in electrochemical capacitor electrode material. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for graphene/carbon nano-tube composite material, prepared by the above method.