Boron-containing solid polymer electrolyte and preparation method and application thereof

The invention belongs to the technical field of an electrolyte material, especially a boron-containing solid polymer electrolyte and a preparation method and application thereof. The polymer electrolyte provided by the invention comprises high molecular polymer matrix and electrolyte salt. The preparation method comprises the steps of esterifying boric acid-containing compounds and alkene compounds with diol structures, thereby obtaining boron heterocycle-containing vinyl monomer, uniformly dispersing the boron heterocycle containing vinyl monomer, initiator, the electrolyte salt and organic solvent, carrying out free radical polymerization, and drying obtained mixture, thereby obtaining the boron-containing solid polymer electrolyte. The boron-containing solid polymer electrolyte has the advantages of high ion conductivity, high cation transference number, good mechanical property and excellent electrode/electrolyte interface interaction and can be applied to fields such as a supercapacitor, a lithium ion battery, a hybrid supercapacitor and a fuel battery. The supercapacitor assembled with the polymer electrolyte has the advantages of wide electrochemical window, long cycle life and high security.