Lithium secondary battery electrolyte for formation of multilayer solid electrolyte interface layer, and lithium secondary battery including same

An electrolyte for a lithium secondary battery, the electrolyte comprising:

• a solution comprising an organic solvent, a co-solvent comprising a fluorine-based compound and being a different kind from the organic solvent, and a lithium salt;
• a first additive comprising a fluorine element;
• a second additive comprising a nitrogen element;
• and
• a third additive comprising a cyclic carbonate-based compound.