Non-aqueous electrolyte solution additive, and non-aqueous electrolyte solution for lithium secondary battery and lithium secondary battery which include the same

Patent metadata

Field	Value
Publication number	US-11081728-B2
Application number	US-201816338578-A
Country	US
Kind code	B2
Filing date	Jul 6, 2018
Priority date	Jul 14, 2017
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

The present invention relates to a non-aqueous electrolyte solution additive, and a non-aqueous electrolyte solution for a lithium secondary battery and a lithium secondary battery which include the same, and particularly, to a non-aqueous electrolyte solution additive including a compound based on a cyclic sulfur structure, and a secondary battery in which low-voltage failure due to metal dissolution may be improved by including the same.

First claim

The invention claimed is:

1. A non-aqueous electrolyte solution additive which is a compound represented by Formula 1:

wherein, in Formula 1,
R 1 to R 5 are each independently C—(R) 2 or C═O, wherein R in each R 1 to R 5 when being C—(R) 2 is same or different, and is selected from hydrogen or an alkyl group having 1 to 3 carbon atoms, and at least one of R 1 to R 5 is C—(R) 2 or C═O, wherein R is an alkyl group having 1 to 3 carbon atoms.

2. The non-aqueous electrolyte solution additive of claim 1 , wherein the compound represented by Formula 1 comprises at least one selected from the group consisting of compounds represented by Formulae 1b to 1d:

3. A non-aqueous electrolyte solution for a lithium secondary battery, the non-aqueous electrolyte solution comprising:
a lithium salt;
an organic solvent; and
a non-aqueous electrolyte solution additive,
wherein the non-aqueous electrolyte solution additive is the non-aqueous electrolyte solution additive of claim 1 .

4. The non-aqueous electrolyte solution for a lithium secondary battery of claim 3 , wherein the non-aqueous electrolyte solution additive is included in an amount of 0.05 wt % to 5 wt % based on a total amount of the non-aqueous electrolyte solution.

5. The non-aqueous electrolyte solution for a lithium secondary battery of claim 4 , wherein the non-aqueous electrolyte solution additive is included in an amount of 0.5 wt % to 3 wt % based on the total amount of the non-aqueous electrolyte solution.

6. 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 positive electrode comprises at least one positive electrode active material selected from the group consisting of a lithium-nickel-manganese-cobalt-based oxide and a lithium-manganese-based oxide, and
the non-aqueous electrolyte solution is the non-aqueous electrolyte solution for a lithium secondary battery of claim 3 .

7. The lithium secondary battery of claim 6 , wherein the positive electrode active material comprises a lithium-manganese-based oxide.

8. The lithium secondary battery of claim 7 , wherein the lithium-manganese-based oxide is LiMn 2 O 4 .

9. The non-aqueous electrolyte solution for a lithium secondary battery of claim 3 , wherein the lithium salt comprises Li + as a cation, and any one selected from the group consisting of F − , Cl − , Br − , I − , NO 3 − , N(CN) 2 , BF 4 — , ClO 4 — , AlO 4 — , AlCl 4 — , PF 6 — , SbF 6 — , AsF 6 — , BF 2 C 2 O 4 — , BC 4 O 8 — , (CF 3 ) 2 PF 4 — , (CF 3 ) 3 PF 3 — , (CF 3 ) 4 PF 2 — , (CF 3 ) 5 PF — , (CF 3 ) 6 P — , CF 3 SO 3 — , C 4 F 9 SO 3 — , CF 3 CF 2 SO 3 — , (CF 3 SO 2 ) 2 N — , (FSO 2 ) 2 N — , CF 3 CF 2 (CF 3 ) 2 CO — , (CF 3 SO 2 ) 2 CH — , (SF 5 ) 3 C — , (CF 3 SO 2 ) 3 C — , CF 3 (CF 2 ) 7 SO 3 — , CF 3 CO 2 — , CH 3 CO 2 , SCN — , and (CF 3 CF 2 SO 2 ) 2 N — as an anion.

10. The non-aqueous electrolyte solution for a lithium secondary battery of claim 3 , wherein the organic solvent comprises at least one selected from an ether-based solvent, an ester-based solvent, or an amide-based solvent.

11. The non-aqueous electrolyte solution for a lithium secondary battery of claim 3 , wherein the organic solvent comprises at least one selected from a cyclic carbonate compound, a linear carbonate compound, a linear ester compound, or a cyclic ester compound.

12. The non-aqueous electrolyte solution for a lithium secondary battery of claim 11 , wherein the linear carbonate compound comprises at least one selected from the group consisting of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate, ethylmethyl carbonate (EMC), methylpropyl carbonate, and ethylpropyl carbonate.

13. The non-aqueous electrolyte solution for a lithium secondary battery of claim 11 , wherein the cyclic carbonate compound comprises 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, vinylene carbonate, and fluoroethylene carbonate.

14. The non-aqueous electrolyte solution for a lithium secondary battery of claim 3 , further comprising an additive selected from a silicon-based compound including a vinyl group, vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, cyclic sulfite, saturated sultone, unsaturated sultone, a non-cyclic sulfone, or a combination thereof.

15. The lithium secondary battery of claim 6 , wherein the positive electrode active material further comprises at least one lithium transition metal oxide selected from the group consisting of lithium-cobalt-based oxide, lithium-nickel-based oxide, lithium-nickel-manganese-based oxide, lithium-nickel-cobalt-based oxide, lithium-manganese-cobalt-based oxide, and lithium-nickel-cobalt-transition metal oxide.

Assignees

• Lg Chemical Ltd

Inventors

• Kim Hyun Seung
• Yu Sung Hoon

Classifications

• H01M10/0567 Primary

  characterised by the additives · CPC title

• C07D341/00 Primary

  Heterocyclic compounds containing rings having three or more sulfur atoms as the only ring hetero atoms · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/4235

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title

• H01M10/052

  Li-accumulators · CPC title