The invention discloses an electrolyte and a battery thereof, the electrolyte comprises an electrolyte salt, an organic solvent and an additive, and the additive comprises at least one of an additive A, an additive B and an additive C; wherein the additive B is fluoroethylene carbonate; the additive C is two or more of vinylene carbonate, 1, 3-propane sultone, ethylene sulfate, butanedinitrile, adiponitrile, 1, 3, 6-hexane trinitrile, propene sultone, methylene methanedisulfonate, ethylene glycol bis (propionitrile) ether and fluorine-containing ether, and the additive C is one or more of ethylene carbonate, 1, 3-propane sultone, ethylene sulfate, butanedinitrile, adiponitrile, 1, 3, 6-hexane trinitrile, propene sultone, methylene methanedisulfonate, ethylene glycol bis (propionitrile) ether and fluorine-containing ether. The additive A has a structural general formula I shown in the specification, wherein R1 is any one of fluorine atoms, alkyl and alkyl substituents; r2 is any one of-CnH2n-and-Cn + 1H2n-, wherein n is greater than or equal to 1 and less than or equal to 5; and R3 to R5 are respectively selected from any one of alkyl and alkyl substitutes.