Separator of lithium-ion-battery preparation and method thereof

A preparation method of a separator of a lithium-ion battery, comprising steps of:

• step 1, adding ceramic particles and solid polymer wax powders into water and obtaining a uniform mixture with stirring, then adding the uniform mixture into a ball mill for grinding to make the particle diameters of the ceramic particles and the solid polymer wax powders less than 2 μm, and obtaining a primary slurry;
• step 2, adding an adhesive into the primary slurry obtained in step 1 and obtaining a uniform mixture with stirring, then filtrating the uniform mixture by a 300-mesh screen, and obtaining a coating slurry;
• step 3, coating the coating slurry obtained in step 2 onto a surface of a substrate membrane by intaglio printing or extrusion coating, which was followed by a drying to obtain a coating, and obtaining a separator of a lithium-ion battery;
• the coating comprising 10˜70 wt % of ceramic particles, 20˜80 wt % of a solid polymer wax and 5˜20 wt % of an adhesive, a melting point of the solid polymer wax being 85˜120° C., a relative molecular weight of the solid polymer wax being 1,000˜25,000, and the particle size of the solid polymer wax being larger than a pore size of the substrate membrane.