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

Patent metadata

Field	Value
Publication number	US-12283663-B2
Application number	US-202218281485-A
Country	US
Kind code	B2
Filing date	Sep 14, 2022
Priority date	Sep 14, 2021
Publication date	Apr 22, 2025
Grant date	Apr 22, 2025

Abstract

A non-aqueous electrolyte solution for a lithium secondary battery includes a compound represented by Formula 1 as follows, a lithium salt, and an organic solvent; and a lithium secondary battery including the same:

wherein R1 to R3, L1 and A − are described herein.

First claim

The invention claimed is:

1. A non-aqueous electrolyte solution for a lithium secondary battery, the non-aqueous electrolyte solution comprising a lithium salt; an organic solvent; and a compound represented by Formula 1:

wherein, in Formula 1,
R1 to R3 are each independently an alkyl group having 1 to 6 carbon atoms and optionally substituted with a fluorine, an alkenyl group having 2 to 6 carbon atoms and optionally substituted with a fluorine, an alkynyl group having 2 to 6 carbon atoms and optionally substituted with a fluorine, or —R′OSi(R4) 3 ;
R′ is a direct linkage; an alkylene group having 1 to 6 carbon atoms and optionally substituted with a fluorine, an alkenylene group having 2 to 6 carbon atoms and optionally substituted with a fluorine, or an alkynylene group having 2 to 6 carbon atoms and optionally substituted with a fluorine;
R4 is an alkyl group having 1 to 6 carbon atoms;
L1 is —(CO) m O(CH 2 ) n − ;
m is 0 or 1;
n is an integer of 0 to 5; and
A − is (CF 3 SO 2 ) 2 N − , (FSO 2 ) 2 N − , PF 6 − , PO 2 F 2 − , BF 4 − , ClO 4 − , (C 2 O 4 )BF 2 − , HSO 4 − , CF 3 SO 3 − , (C 2 F 5 SO 2 ) 2 N − , C(CF 2 SO 2 ) 3 − , AsF 6 − , SbF 6 − , AlCl 4 − , NbF 6 − , or CF 3 CO 2 − .
wherein the compound represented by Formula 1 is included in an amount of 0.05 wt % to 5 wt % with respect to a total weight of the non-aqueous electrolyte solution.

2. The non-aqueous electrolyte solution of claim 1 , wherein the compound represented by Formula 1 is represented by Formula 1-1 or Formula 1-2:

wherein, in Formula 1-1 and Formula 1-2,
R1 to R3, n, and A − are the same as defined in Formula 1.

3. The non-aqueous electrolyte solution of claim 1 , wherein R1 to R3 are each independently —R′OSi(CH 3 ) 3 , and
R′ is a direct linkage or an alkylene group having 1 to 6 carbon atoms.

4. The non-aqueous electrolyte solution of claim 3 , wherein R′ is a methylene group.

5. The non-aqueous electrolyte solution of claim 1 , wherein each of R1 to R3 is an ethylene group.

6. The non-aqueous electrolyte solution of claim 1 , wherein A − is (CF 3 SO 2 ) 2 N − or (FSO 2 ) 2 N − .

7. The non-aqueous electrolyte solution of claim 1 , further comprising at least one additive selected from ethylene carbonate, vinylene carbonate, 1,3-propane sultone, vinylethylene carbonate, fluoroethylene carbonate, lithium difluoro oxalato borate, ethylene sulfate, propargyl 1H-imidazole-1-carboxylate, methyl prop-2-ynyl carbonate, ethylene glycol bis(propionitrile) ether, fluorobenzene, difluorobenzene, hexafluorobenzene, 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethylether, bis(trifluoromethyl)-1,3-dioxolane, or 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether.

8. The non-aqueous electrolyte solution of claim 1 , wherein the organic solvent is a mixture of a cyclic carbonate-based solvent and a linear carbonate-based solvent.

9. A lithium secondary battery comprising:
a positive electrode including a positive electrode active material;
a negative electrode including a negative electrode active material;
a separator disposed between the positive electrode and the negative electrode; and
the non-aqueous electrolyte solution of claim 1 .

10. The lithium secondary battery of claim 9 , wherein the positive electrode active material comprises a lithium composite transition metal oxide represented by Formula 2:
Li 1+x (Ni a Co b Mn c M d )O 2   [Formula 2]

wherein, in Formula 2,
M is at least one selected from W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, or Mo,
1+x, a, b, c, and d are each an atomic fraction of Li, Ni, Co, Mn and M, respectively, and
−0.2≤x≤0.2, 0.50≤a<1, 0<b≤0.40, 0<c≤0.40, 0≤d≤0.10, and a+b+c+d=1.

11. The non-aqueous electrolyte solution of claim 1 , wherein the compound represented by Formula 1 is represented by any one of Formulae 1A, 1B, 1C or 1D:

12. The non-aqueous electrolyte solution of claim 7 , wherein the at least one additive is included in an amount of 0.1 wt % to 10 wt % based on a total weight of the non-aqueous electrolyte solution.

13. The non-aqueous electrolyte solution of claim 1 , wherein the lithium salt is at least one selected from LiPF 6 , LiClO 4 , LiBF 4 , LiN(FSO 2 ) 2 , Lithium bis(trifluoromethanesulfonyl)imide, lithium bis(pentafluoroethanesulfonyl)imide, LiSO 3 CF 3 , LiPO 2 F 2 , lithium bis(oxalate)borate, lithium difluoro(oxalate)borate, lithium difluoro(bisoxalato) phosphate, lithium tetrafluoro(oxalate) phosphate, or lithium fluoromalonato(difluoro) borate.

14. The lithium secondary battery of claim 10 , wherein the lithium composite transition metal oxide comprises at least one selected from 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 , or Li(Ni 0.9 Mn 0.03 Co 0.06 Al 0.01 )O 2 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Park Sol Ji
• Lee Jung Hoon
• Lee Chul Haeng
• Kang Yoo Sun
• Lee Jae Won

Classifications

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M10/0568

  characterised by the solutes · CPC title

• H01M10/0525 Primary

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title