▎ 摘　　要

NOVELTY - The utility model claims a battery diaphragm, the battery diaphragm comprises a graphene layer, one side surface of the graphene layer is orderly laminated with a first polyolefin layer and a first ceramic layer, the other side surface of the graphene layer is orderly laminated with a second polyolefin layer and a second ceramic layer. The sandwich structure battery diaphragm of the utility model, because of the heat insulation and support of the ceramic layer, the heat resistance of the diaphragm is greatly improved, improving the thermal safety of the diaphragm and the electrolyte of the membrane wetting property, two sides of the polyolefin layer effectively increases the diaphragm strength, reduces the probability of damage of the diaphragm; convenient for the membrane to work for a long time, prolonging the service life of the membrane.