The invention relates to the field of
lithium ion battery diaphragm preparation and relates to an inorganic
coating high-temperature resisting type
lithium ion battery diaphragm with a special structure and the preparation method thereof. The
lithium ion battery diaphragm comprises a porous flexible
basement membrane and coatings coated on the two sides of the
basement membrane, and composites of
inorganic particles and organic
microsphere are contained in the coatings. The
inorganic particles and the organic microspheres are mixed into the
solvent according to a certain proportion, homogeneous membrane
coating slurry can be obtained, the
slurry is coated on the two surfaces of the flexible and organic
basement membrane, and then, under a certain temperature, the composite diaphragm with favorable performance is obtained through the pressing of a hot roller. In the inorganic
coating lithium ion battery diaphragm provided by the invention, bonding agent is not directly added into the membrane coating
slurry, damages to the
microstructure of the diaphragm caused by the bonding agent can be avoided, the high-temperature resisting performance and the
electrolyte infiltrating performance of the diaphragm are greatly improved, and the composite
lithium ion battery diaphragm prepared by the invention has the advantages of superior comprehensive performance, easiness in big-scale and large-dimension production and the like.