▎ 摘　　要

NOVELTY - A graphene-nano fiber composite membrane has an intermediate layer covering a lower layer and an upper layer covering the intermediate layer. The upper layer and lower layer comprise polyvinylidene fluoride (PVDF)-based polymer nano fiber layer, and the intermediate layer comprises PVDF-based graphene nano fiber layer. USE - Graphene-nano fiber composite membrane for lithium ion battery. ADVANTAGE - The graphene-nano fiber composite membrane has high porosity, large specific surface area, excellent absorption rate, excellent wettability, tensile strength, and maintains normal operation of the lithium battery production equipment. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the composite membrane.