▎ 摘　　要

NOVELTY - A lithium-sulfur battery has a protective layer coated on a membrane surface of slurry comprising modified graphene-containing functional groups and binder in a mass ratio of 4-9:1. USE - Lithium-sulfur battery. ADVANTAGE - The protective layer of the battery can effectively prevent the shuttle in a polysulfide electrolyte, ensure more uniform discharge products deposited on the electrode surface, and increase capacity ratio and cycle life of the lithium-sulfur battery. DETAILED DESCRIPTION - A lithium-sulfur battery has a protective layer coated on a membrane surface of slurry comprising modified graphene-containing functional groups and binder in a mass ratio of 4-9:1, where the functional groups are alkyl group, olefin group, aromatic group, halogen, cyano, -CN, -SCN, -NCO , -OH, -COOH, -NH2, -COX, -NO2, -SO3H, -COOR, -COR, -CONHR, -CONR2, -OR, -NHR and/or -NR2, X is F, Cl, Br or I, and R is alkyl, alkene or aromatic group. INDEPENDENT CLAIMS are also included for the following: (1) a method for preparing a protective layer of the lithium-sulfur battery (2) a method for using the lithium-sulfur battery.