Meta-aramid polymer with grid structure, and preparation method therefor and use thereof

Abstract

In the process of forming the meta-aramid polymer, alkyl is introduced among macromolecules through alkylation, such that adjacent molecular chains are linked by a chemical bond so as to form a grid structure. A coating slurry prepared from the meta-aramid polymer with a grid structure, a pore-forming agent and a cosolvent are coated on the surface of a polyolefin porous separator so as to obtain a high-performance lithium battery coated separator. Compared with a coated separator prepared by a traditional method, the coated separator prepared by the present disclosure has higher heat resistance, thermal shrinkage resistance and puncture strength, has better wettability with an electrolyte, and thus can prolong a cycle life of a battery. The coated separator of the meta-aramid with a grid structure can further improve the oxidation resistance, is beneficial to realizing high potential and improves energy density.