Electrolyte, and lithium metal secondary battery, battery pack, battery module and electric device comprising same

The invention provides an electrolyte, which comprises an electrolyte lithium salt and an organic solvent, and the organic solvent comprises: a) a first solvent, which is selected from at least one of acetal compounds; the second solvent is selected from at least one of benzene ring-containing fluoroether compounds; the invention also provides a lithium metal secondary battery containing the electrolyte, a battery pack, a battery module and an electric device. And the cycle performance and the charge-discharge performance at high rate of the lithium-ion battery are remarkably improved.