Electrolyte and battery

The invention provides an electrolyte and a battery. The first aspect of the invention provides an electrolyte, the electrolyte comprises a first lithium salt, a second lithium salt and a first additive, the first lithium salt at least comprises lithium bis (fluorosulfonyl) imide, and the second lithium salt is selected from one or two of lithium difluoro (oxalato) borate and lithium difluoro (oxalato) phosphate; the first additive is methylene methanedisulfonate. On the basis that the electrolyte provided by the invention comprises the first lithium salt and the second lithium salt, the first additive methylene methanedisulfonate (MMDS) is also added, the second lithium salt is beneficial to improving the cycling stability and high-temperature storage performance of the battery, and the first additive is matched to be beneficial to improving the oxidation resistance of the second lithium salt under high voltage; the composition and the structure of the SEI film are further modified, the impedance of the SEI