Non-aqueous electrolyte solution for lithium secondary battery and lithium secondary battery including the same
The present invention relates to a non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery including the same, and particularly, to a non-aqueous electrolyte solution for a lithium secondary battery which includes an ionizable lithium salt, an organic solvent, and an additive, wherein the additive includes tetravinylsilane, lithium difluorophosphate, and 1,3-propylene sulfate in a weight ratio of 1:3 to 20:3 to 20, and a total amount of the additive is in a range of 1 wt % to 4 wt % based on a total weight of the non-aqueous electrolyte solution for a lithium secondary battery, and a lithium secondary battery including the same.
1. A non-aqueous electrolyte solution for a lithium secondary battery, the non-aqueous electrolyte solution comprising:
an ionizable lithium salt;
an organic solvent; and
an additive,
wherein the additive is a mixed additive which includes tetravinylsilane, lithium difluorophosphate, and 1,3-propylene sulfate in a weight ratio of 1:3 to 20:3 to 20, and
the additive is included in an amount of 1 wt % to 4 wt % based on a total weight of the non-aqueous electrolyte solution.
2. The non-aqueous electrolyte solution for a lithium secondary battery of claim 1 , wherein the weight ratio of the tetravinylsilane:the lithium difluorophosphate:the 1,3-propylene sulfate is in a range of 1:3 to 17:5 to 20.
3. The non-aqueous electrolyte solution for a lithium secondary battery of claim 1 , wherein the weight ratio of the tetravinylsilane:the lithium difluorophosphate:the 1,3-propylene sulfate is in a range of 1:5 to 15:5 to 20.
4. The non-aqueous electrolyte solution for a lithium secondary battery of claim 1 , wherein the additive is included in an amount of 1.8 wt % to 4 wt % based on the total weight of the non-aqueous electrolyte solution for a lithium secondary battery.
5. The non-aqueous electrolyte solution for a lithium secondary battery of claim 1 , further comprising at least one additional additive selected from the group consisting of vinylene carbonate, LiBF 4 , 1,3-propane sultone, and tetraphenylborate.
6. The non-aqueous electrolyte solution for a lithium secondary battery of claim 5 , wherein the additional additive is included in an amount of 0.1 wt % to 5 wt % based on the total weight of the non-aqueous electrolyte solution.
7. The non-aqueous electrolyte solution for a lithium secondary battery of claim 5 , wherein, in a case in which the 1,3-propane sultone is included as the additional additive, a weight ratio of the tetravinylsilane:the 1,3-propane sultone is in a range of 1:5 to 1:15.
8. The non-aqueous electrolyte solution for a lithium secondary battery of claim 5 , wherein, in a case in which the vinylene carbonate or LiBF 4 is included as the additional additive, a weight ratio of the tetravinylsilane:the vinylene carbonate or LiBF 4 is in a range of 1:1 to 1:3.
9. A lithium secondary battery comprising a negative electrode, a positive electrode, a separator disposed between the negative electrode and the positive electrode, and a non-aqueous electrolyte solution,
wherein the non-aqueous electrolyte solution comprises the non-aqueous electrolyte solution for a lithium secondary battery of claim 1 , and
the positive electrode comprises a lithium-nickel-manganese-cobalt-based oxide as a positive electrode active material.
10. The lithium secondary battery of claim 9 , wherein the positive electrode active material comprises a lithium transition metal oxide represented by Formula 1:
Li(Ni a Co b Mn c )O 2 [Formula 1]
wherein, in Formula 1,
0.55≤a≤0.9, 0.05≤b≤0.22, 0.05≤c≤0.23, and a+b+c=1.
11. The lithium secondary battery of claim 10 , wherein the positive electrode active material comprises at least one of Li(Ni 0.6 Mn 0.2 Co 0.2 )O 2 , Li(Ni 0.7 Mn 0.15 Co 0.15 )O 2 , Li(Ni 0.8 Mn 0.1 Co 0.1 )O 2 .