The invention discloses a wide-temperature-range
electrolyte and application thereof, and belongs to the technical field of supercapacitors. The wide-temperature-range
electrolyte comprises the following components in percentage by
mass: 12.5%-15% of
lithium salt, 0.3%-1% of [2, 2 '-dinaphthalene]-7-yl
trifluoromethanesulfonate, 0.5%-1.5% of a
sulfur additive, 0.5%-1% of a
lithium salt additive and the balance of an
organic solvent, by taking the total volume of the
organic solvent as 100%, the volume ratio of the 2-bromo-5-fluoroisonicotinic acid methyl ester to the total volume of the
ethylene carbonate and the
propylene carbonate to the
diethyl carbonate to the ethyl
methyl carbonate is (5-10): (10-15): (10-20): (50-65). Experiments prove that by adding the methyl 2-bromo-5-fluoroisonicotinate and the functional [2, 2 '-dinaphthalene]-7-yl
trifluoromethanesulfonate into the
electrolyte, the high and low temperature
discharge performance, especially the low temperature performance, of the
supercapacitor can be remarkably improved, and the highest
discharge capacity
retention rate at-20 DEG C is 84.5%. Therefore, the wide-temperature-range electrolyte prepared by the method can solve the problem that a traditional
supercapacitor electrolyte is difficult to consider high and low temperature performance at the same time.