▎ 摘　　要

NOVELTY - A modified diaphragm includes a diaphragm base, and electroconductive coating and inorganic hard coating respectively located at the both surfaces of diaphragm base. The electroconductive coating is mixed coating containing graphene and porous carbon material. The inorganic hard coating includes nitrogen and carbon material coating, silicon nitride coating material, carborane material coating or Silicon carbide material coating. USE - Modified diaphragm is used for lithium sulfur battery (claimed). ADVANTAGE - The highly-safe modified diaphragm has excellent absorption capacity and high ionic conductivity, and is capable of preventing short-circuit. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) preparation of modified diaphragm, which involves mixture electroconductive material, binder and dispersant, grinding uniformly, obtaining electroconductive slurry, mixing inorganic hard material, binder and dispersant, grinding uniformly, obtaining inorganic hard material slurry, coating electroconductive slurry on one surface of membrane, drying, coating inorganic hard material slurry on other surface of the membrane and drying; and (2) lithium sulfur battery, which has an anode, a cathode and the modified diaphragm.