CPC H01M 50/489 (2021.01) [H01M 10/4235 (2013.01); H01M 50/403 (2021.01); H01M 50/417 (2021.01); H01M 50/434 (2021.01); H01M 50/451 (2021.01); H01M 50/457 (2021.01); H01M 50/491 (2021.01)] | 18 Claims |
1. A ceramic-and-polymer-compositely-coated lithium ion separator having bonding strength with pole pieces of at least 39N/M, and comprising:
a polyolefin porous membrane, a ceramic coating coated onto one or both sides of the membrane surface, and a polymer coating coated onto the ceramic surface or the membrane surface, wherein
the ceramic coating is made by following raw materials in parts by weight: 15-45 parts of a ceramic material, 0.5-8 parts of an aqueous dispersant, 1-10 parts of an aqueous binder, 1-5 parts of an aqueous binder emulsion, and 0.1-5 parts of an aqueous wetting agent, wherein
the aqueous binder emulsion is composed of following raw materials in parts by weight: 1-10 parts of sodium carboxymethyl cellulose, 1.5-5 parts of a high dielectric constant ceramic material, 5-20 parts of a monomer for synthesis of acrylic resin, 0.1-0.5 parts of ammonium persulfate, and 0.2-2 parts of a surfactant, and
the high dielectric constant ceramic material in the aqueous binder emulsion is at least one selected from the group consisting of rutile titanium dioxide, barium titanate, potassium niobate and sodium niobate, and wherein a total surface density of the ceramic-and-polymer-compositely-coated lithium ion separator is 3-50 g/m2.
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