Electrolyte Solution for Lithium Secondary Battery and Lithium Secondary Battery Including the Same
An electrolyte for a lithium secondary battery includes an organic solvent in an amount ranging from 90 wt % to 96% based on a total weight of the electrolyte solution, a lithium salt in an amount ranging from 0.01 wt % to 5 wt % based on the total weight of the electrolyte solution, and a triphenyl phosphate-based additive in an amount ranging from 3 wt % to 7 wt % based on the total weight of the electrolyte solution.
1 . An electrolyte solution for a lithium secondary battery, comprising:
an organic solvent in an amount ranging from 90 wt % to 96% based on a total weight of the electrolyte solution;
a lithium salt in an amount ranging from 0.01 wt % to 5 wt % based on the total weight of the electrolyte solution; and
a triphenyl phosphate-based additive in an amount ranging from 3 wt % to 7 wt % based on the total weight of the electrolyte solution.
2 . The electrolyte solution for a lithium secondary battery according to claim 1 , wherein the triphenyl phosphate-based additive comprises a compound represented by Chemical Formula 1:
wherein, in Chemical Formula 1, R 1 , R 2 and R 3 are each independently an aryl group.
3 . The electrolyte solution for a lithium secondary battery according to claim 2 , wherein the triphenyl phosphate-based additive comprises a compound represented by Chemical Formula 1-1 or a compound represented by Chemical Formula 1-2:
4 . The electrolyte solution for a lithium secondary battery of claim 2 , wherein the triphenyl phosphate-based additive comprises a compound represented by Chemical Formula 1-1 and a compound represented by Chemical Formula 1-2:
5 . The electrolyte solution for a lithium secondary battery according to claim 4 , wherein a weight ratio of the compound represented by Chemical Formula 1-2 to the compound represented by Chemical Formula 1-1 is in a range from 1/9 to 9.
6 . The electrolyte solution for a lithium secondary battery according to claim 1 , wherein the electrolyte solution further comprises at least one borate-based lithium salt selected from the group consisting of lithium tetrafluoro borate, lithium bis(oxalate)borate, lithium difluoro(oxalato)borate and lithium bis(2-methyl-2-fluoro-malonato)borate.
7 . The electrolyte solution for a lithium secondary battery according to claim 6 , wherein the borate-based lithium salt includes lithium bis(oxalate)borate.
8 . The electrolyte solution for a lithium secondary battery according to claim 6 , wherein the borate-based lithium salt is included in an amount ranging from 0.01 wt % to 5 wt % based on the total weight of the electrolyte solution.
9 . The electrolyte solution for a lithium secondary battery according to claim 1 , wherein the electrolyte solution further comprises at least one auxiliary additive selected from the group consisting of a cyclic carbonate-based compound, a fluorine-substituted cyclic carbonate-based compound, a sultone-based compound, a cyclic sulfate-based compound and an oxalatophosphate-based compound.
10 . The electrolyte solution for a lithium secondary battery according to claim 9 , wherein the auxiliary additive is included in an amount ranging from 0.01 wt % to 5 wt % based on the total weight of the electrolyte solution.
11 . The electrolyte for a lithium secondary battery according to claim 1 , wherein the organic solvent includes at least one selected from the group consisting of ethylene carbonate (EC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC) and diethyl carbonate (DEC).
12 . A lithium secondary battery, comprising:
an electrode assembly in which a plurality of cathodes and anodes are repeatedly stacked;
a case accommodating the electrode assembly; and
the electrolyte solution for a lithium secondary battery of claim 1 accommodated together with the electrode assembly in the case.