▎ 摘　　要

NOVELTY - Preparing functional membrane involves coating first slurry on anode side of polyolefin film, and drying to obtain first coating. The second slurry is coated on first coating, and dried to obtain second coating on first coating for obtaining functional diaphragm for lithium sulfur battery. The first slurry is prepared by mixing first mixed solution and second mixed solution uniformly and sand grinded to obtain first slurry. The second mixed solution is 1-25 wt.% of first mixed solution, and first mixed solution is prepared by mixing 1-20 pts. wt. water and 1 pts. wt. absolute ethyl alcohol, adding 0.1-0.5 pts. wt. dispersant, and stirring uniformly to obtain first mixed solution. The second mixed solution is composed of carbon conductor and adhesive, where mass ratio of carbon conductor and adhesive is 10-90:0.5-5. The carbon conductor is graphene, Super-p or carbon black. USE - Method for preparing functional membrane for lithium sulfur battery used for improving the electrolyte wetting property of the membrane (claimed). ADVANTAGE - The method enables to improve electrolyte wetting property of the membrane so as to improve ion conductivity and lithium ion migration number of the membrane, and improve cycle performance and rate performance of battery. DETAILED DESCRIPTION - Preparing functional membrane involves coating first slurry on anode side of polyolefin film, and drying to obtain first coating. The second slurry is coated on first coating, and dried to obtain second coating on first coating for obtaining functional diaphragm for lithium sulfur battery. The first slurry is prepared by mixing first mixed solution and second mixed solution uniformly and sand grinded to obtain first slurry. The second mixed solution is 1-25 wt.% of first mixed solution, and first mixed solution is prepared by mixing 1-20 pts. wt. water and 1 pts. wt. absolute ethyl alcohol, adding 0.1-0.5 pts. wt. dispersant, and stirring uniformly to obtain first mixed solution. The second mixed solution is composed of carbon conductor and adhesive, where mass ratio of carbon conductor and adhesive is 10-90:0.5-5. The carbon conductor is graphene, Super-p or carbon black, dispersant is ammonium polyacrylate, trimethyl ammonium hydrochloride, and polyethylene glycol, and adhesive is polyvinylidene fluoride (PVDF) or polyacrylic ester. The second slurry is prepared by mixing water and absolute ethyl alcohol uniformly to obtain third mixed solution, adding amphiphilic polymer material in third mixed solution, stirring uniformly to obtain second slurry, where amphiphilic polymer material is polyethylene glycol-b-polycaprolactone, polyethylene glycol-b-polylactic acid, polyoxyethylene polyoxypropylene block copolymer or alkyl phenolpolyoxyethylene ether, mass ratio of water and absolute ethyl alcohol in third mixed solution is 1-15:1-6, and amphiphilic polymer material is 0.6-6 wt.% of third mixed solution.