The invention discloses a thermal self-closing
ceramic modified diaphragm and a preparation method thereof, and belongs to the technical field of
lithium battery diaphragms, the thermal self-closing
ceramic modified diaphragm comprises a
polyolefin diaphragm substrate, at least one surface of the
polyolefin diaphragm substrate forms a
corona treatment surface, and the
corona treatment surface is coated with a thermal self-closing
ceramic coating. The invention discloses a preparation method of a thermal self-closing ceramic modified diaphragm. The method comprises the following steps: S1, preparing a thermal self-closing
ceramic coating, S2, unwinding the
polyolefin diaphragm base material; S3, carrying out
corona treatment on the
coated surface of the polyolefin diaphragm base material; after
corona treatment is finished,
coating the thermal self-closing
ceramic coating prepared in the step S1; and S4,
drying and shaping the coated polyolefin diaphragm base material; and S5, after
drying is completed, conducting rolling, conducting standing and curing for 6-8 days at the normal temperature, and obtaining the thermal self-closing ceramic modified diaphragm. The thermal self-closingceramic modified diaphragm and the preparation method thereof have the advantages that the thermal self-closing performance is achieved, the safety is improved, the
thermal curing performance is achieved, and the diaphragm breaking temperature is increased.