▎ 摘　　要

NOVELTY - A fluorocarbon material comprises carbon material and fluoropolymer. The fluorocarbon material has carbon-fluorine covalent bond. USE - The fluorocarbon material is used for fluorocarbon material layer for lithium metal battery (all claimed). ADVANTAGE - The fluorine-containing material can generate fluoride-rich protective layer on the lithium metal battery anode, cathode or membrane in situ, which is good for uniform lithium ion flow, reduces the generation of dendritic crystal, improves the safety of the battery. The fluorocarbon material not only provides a support structure for metal deposition without main body, inhibits the volume expansion of the lithium metal, but also provides a protective layer, can isolate the fresh metal and electrolyte contact generating side reaction, so as to improve the coulomb efficiency. The raw material price is cheap, the preparation method is simple, saving the cost of lithium metal battery protection; and the material has light weight; and can greatly improve the energy density of the battery. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparation of the fluorocarbon material comprising adding carbon material and fluoropolymer into solvent B, mixing to obtain homogeneous phase mixture, adding to solvent A, precipitating, and sintering precipitate under reducing atmosphere; (2) a fluorocarbon material layer comprising fluorocarbon material and substrate; (3) preparation of fluorocarbon material layer comprising adding binder to fluorocarbon material at mass ratio of 60-90:10-40, mixing into homogeneous phase, coating on surface of substrate, and drying; and (4) a lithium metal battery comprising fluorocarbon material and/or fluorocarbon material layer, positive electrode, negative electrode, and separator coated with fluorocarbon material or attached to fluorocarbon material layer. The solvent B comprises N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide and/or dimethylsulfoxide. The solvent A comprises water, methanol and/or ethanol. One surface of substrate is coated with fluorocarbon material. The binder comprises polyimide, polyvinylidene fluoride, polyacrylonitrile, sodium carboxymethyl cellulose, styrene butadiene rubber, polyacrylic acid, PTFE and/or polyvinyl alcohol. The fluorocarbon material or fluorocarbon material layer is located on positive electrode, one surface of negative electrode or separator.