Electrolyte for lithium secondary battery and lithium secondary battery comprising same
Provided is an electrolyte for a lithium secondary battery, the electrolyte including a non-aqueous organic solvent, a lithium salt, and an additive, wherein the additive includes a compound represented by Chemical Formula 1. The definitions of each of the substituents in Chemical Formula 1 are as set forth in the detailed description.
1. An electrolyte for a lithium secondary battery, comprising
a non-aqueous organic solvent;
a lithium salt; and
an additive represented by Chemical Formula 1:
wherein, in Chemical Formula 1,
X 1 and X 2 are each independently O, S, CR a R b , or NR c ,
provided that at least one of X 1 and X 2 is O or S,
L 1 is a substituted or unsubstituted C1 to C10 alkylene group or a substituted or unsubstituted C2 to C10 alkenylene group,
R 1 to R 4 are each independently hydrogen, a C1 to C10 alkyl group, a substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C3 to C10 cycloalkenyl group, a substituted or unsubstituted C6 to C20 an aryl group, or a combination thereof, and
n is an integer of any one of 1 to 3.
2. The electrolyte of claim 1 , wherein
the compound represented by Chemical Formula 1 is represented by Chemical Formula 1A:
wherein, in Chemical Formula 1A,
the definitions of X 1 , X 2 , L 1 , and R 1 to R 4 are the same as in claim 1 .
3. The electrolyte of claim 1 , wherein
the compound represented by Chemical Formula 1 is represented by any one of Chemical Formula 1-1 to Chemical Formula 1-3:
wherein, in Chemical Formula 1-1 to Chemical Formula 1-3,
the definitions of L 1 , R 1 to R 4 , and n are the same as in claim 1 .
4. The electrolyte of claim 1 , wherein
R 1 to R 4 are each independently hydrogen, a C1 to C6 alkyl group, a substituted or unsubstituted C1 to C6 alkoxy group, a substituted or unsubstituted C2 to C6 alkenyl group, a substituted or unsubstituted C3 to C6 cycloalkyl group, a substituted or unsubstituted C3 to C6 cycloalkenyl group, a substituted or unsubstituted C6 to C10 an aryl group, or a combination thereof.
5. The electrolyte of claim 1 , wherein
L 1 is a substituted or unsubstituted C1 to C6 alkylene group.
6. The electrolyte of claim 1 , wherein
the compound represented by Chemical Formula 1 is represented by any one of Chemical Formula 1-a to Chemical Formula 1-r:
7. The electrolyte of claim 1 , wherein
the compound represented by Chemical Formula 1 is included in an amount of 0.1 wt % to 10 wt % based on the total amount of the electrolyte for a lithium secondary battery.
8. The electrolyte of claim 1 , wherein
the compound represented by Chemical Formula 1 is included in an amount of 0.1 wt % to 3.0 wt % based on the total amount of the electrolyte for a lithium secondary battery.
9. A lithium secondary battery, comprising
a positive electrode including a positive active material;
a negative electrode including an anode active material; and
the electrolyte of claim 1 .
10. The lithium secondary battery of claim 9 , wherein
the positive active material includes at least one of a composite oxide of lithium and a metal selected from cobalt, manganese, nickel, and a combination thereof.
11. The lithium secondary battery of claim 9 , wherein
the positive active material is represented by Chemical Formula 2:
Li a Ni x1 CO y1 M z1 O 2 [Chemical Formula 2]
wherein, in Chemical Formula 2,
0.9≤a≤1.8, 0.5<x1≤1, 0<y1≤0.5, 0<z1≤0.5, x1+y1+z1=1, and M is Ni, Co, Mn, Al, Ti, Mg, Zr, Ca, Nb, Fe, P, F, B, or a combination thereof.