POLYMER ELECTROLYTE FOR LITHIUM SECONDARY BATTERY AND LITHIUM SECONDARY BATTERY INCLUDING THE SAME

A polymer electrolyte for a lithium secondary battery according to the embodiments of the present disclosure includes a fluorine-based solvent including a fluorine-containing cyclic carbonate, a fluorine-containing linear carbonate, and a fluorine-containing ether; a lithium salt; and a flame retardant polymer containing phosphorus and fluorine, wherein the content of the fluorine-containing cyclic carbonate, based on the total volume of the fluorine-based solvent, is greater than 20 vol % and less than or equal to 40 vol %.