Flame-retardant gel polymer electrolyte and preparation method thereof

The invention discloses a flame-retardant gel polymer electrolyte and a preparation method thereof, the preparation method comprises the following steps: stirring and dissolving an inorganic Zr-based solid electrolyte in a flame-retardant solvent/fluorocarbonate mixed solution to obtain a mixed solution A in which the solid electrolyte is dissolved, and then adding a lithium salt and a flame-retardant polymer monomer into the flame-retardant solvent/fluorocarbonate mixed solution to dissolve to obtain a mixed solution B; a lithium salt and a solid electrolyte are dissolved in the mixed solution B; and mixing the mixed solution A with the solution B to realize that the solution A initiates defluorination and in-situ crosslinking of the polymer monomer in the mixed solution B, standing, forming, demolding and taking out to form the flame-retardant gel electrolyte for the lithium ion battery, which contains a solid electrolyte and a lithium salt. According to the invention, in-situ synthesis of the flame-retarda