▎ 摘　　要

NOVELTY - A composite graphene ion exchange membrane comprises sulfonated polymer as an ion-exchange membrane substrate, and graphene and/or graphene derivative doped in the ion-exchange membrane substrate. USE - Composite graphene ion exchange membrane is used for flow battery e.g. vanadium redox flow battery, zinc/bromine redox flow battery, iron/chromium-plated flow battery, sodium/bromine redox flow battery, vanadium/bromine flow battery, zinc oxide/cerium flow battery, iron/vanadium redox flow battery, and vanadium/air and vanadium liquid flow battery/hydrogen flow battery (all claimed). ADVANTAGE - The composite graphene ion exchange membrane has excellent stability and ion selectivity, and provides flow battery having high battery efficiency and stable battery performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of composite graphene ion exchange membrane, which involves adding 1-80 %mass sulfonated polymer into organic solvent, and ultrasonically dispersing and/or stirring at 20-100 degrees C for 0.5-48 hours to obtain sulfonated polymer solution, adding 0.001-5 mgmL-1 graphene and/or graphene derivative into organic solvent, and ultrasonically dispersing and/or stirring at 20-100 degrees C for 0.5-48 hours to obtain dispersion of graphene and/or graphene derivative, adding dispersion of graphene and/or graphene derivative into sulfonated polymer solution, ultrasonically dispersing and/or stirring at 20-100 degrees C for 0.5-48 hours, spreading obtained mixture on the substrate, drying at 40-120 degrees C for 2-48 hours and vacuum-drying at 40-140 degrees C for 2-48 hours, and demoulding obtained sulfonated polymer-graphene composite ion-exchange membrane.