The application relates to a preparation method of a
lithium battery diaphragm and belongs to the technical field of
lithium battery preparation. The method is as follows:
epoxy resin, a
diluent, a curing agent 1 and an oleophilic emulsifier are uniformly mixed to obtain dispersion liquid 1; an
electrolyte solution is constantly dropped into the dispersion liquid 1, constant-temperature high-speed stirring is carried out, and a water-in-
oil emulsion is obtained; under constant temperature, deionized water, a hydrophilic emulsifier and a curing agent 2 are uniformly mixed to obtain dispersion liquid 2; the water-in-
oil emulsion is added into the dispersion liquid 2, high-speed emulsification is carried out, and a water-in-oil-in-water
emulsion system is obtained; the water-in-oil-in-water
emulsion system is subjected to temperature rising and curing; after curing,
centrifugal separation, washing and
drying are carried out, and a
solid nanometer
adhesive is obtained; the
solid nanometer
adhesive is ground, then is uniformly coated in a mold and is subjected to high-
temperature treatment, and the
lithium battery diaphragm is obtained. The
electrolyte solution is selected as the inner water phase of the water-in-
oil emulsion, the internal
osmotic pressure of the
emulsion can be increased, fusion between the emulsions can be prevented, and the particle size is increased.