Non-aqueous electrolyte solution for lithium secondary battery and lithium secondary battery including the same

A non-aqueous electrolyte solution for a lithium secondary battery, consisting of:

• a first lithium salt that is lithium bis(fluorosulfonyl)imide (LiFSI);
• a second lithium salt that is LiPF6;
• an organic solvent selected from an ether-based solvent, an ester-based solvent, an amide-based solvent or as a mixture thereof, wherein the ester-based solvent is at least one selected from the group consisting of a cyclic carbonate compound, a linear carbonate compound, an alkyl ether-based compound, an alkyl acetate-based compound, and an alkyl propionate-based compound, and the cyclic carbonate compound is at least one selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene carbonate, and fluoroethylene carbonate (FEC);
• a compound represented by Formula 1;
• and
• optionally, an additive selected from the group consisting of a sultone-based compound, a halogen-substituted carbonate-based compound, a nitrile-based compound, a cyclic sulfite-based compound, and a cyclic carbonate-based compound that is viny1 ethylene carbonate, wherein the sultone-based compound is at least one of 1,3-propane sultone, (PS), 1,4-butane sultone, ethene sultone, 1,4-butene sultone, or 1-methyl-1,3-propene sultone,
• wherein a molar ratio of the second lithium salt to the first lithium salt is in a range of 1:1 to 1:2, and
• wherein the compound represented by Formula 1 is included in an amount of 0.1 wt % to 7 wt % based on a total amount of the non-aqueous electrolyte solution:
• wherein, in Formula 1,
• R1 to R3 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms, and
• A is
• wherein, R4 is hydrogen, an alkyl group having 1 to 6 carbon atoms that is unsubstituted or substituted with at least one fluorine atom, an aryl group having 6 to 8 carbon atoms that is unsubstituted or substituted with at least one fluorine atom, or an alkynyl group having 2 to 6 carbon atoms, and
• R5 is hydrogen, an aryl group having 6 to 8 carbon atoms that is unsubstituted or substituted with at least one fluorine atom, or an alkynyl group having 2 to 6 carbon atoms.