Electrolyte for lithium-sulfur battery and lithium-sulfur battery comprising same

Patent metadata

Field	Value
Publication number	US-2018316068-A1
Application number	US-201715755984-A
Country	US
Kind code	A1
Filing date	Jan 12, 2017
Priority date	Mar 3, 2016
Publication date	Nov 1, 2018
Grant date	—

Abstract

The present invention relates to an electrolyte solution for a lithium-sulfur battery and a lithium-sulfur battery including the same.
The electrolyte solution for a lithium-sulfur battery according to the present invention exhibits excellent stability, and may improve a swelling phenomenon by suppressing gas generation during lithium-sulfur battery operation.

First claim

1 . An electrolyte solution for a lithium-sulfur battery comprising:
a lithium salt; and a non-aqueous solvent, and further comprising a radical adsorbent.

2 . The electrolyte solution for a lithium-sulfur battery of claim 1 , wherein the radical adsorbent includes one type selected from the group consisting of quinone-based compounds, N-oxyl radical-based compounds, phenol-based compounds, amine-based compounds, enol-based compounds, thiol-based compounds, azide-based compounds, cyclopropane derivatives, cyclobutane derivatives and combinations thereof.

3 . The electrolyte solution for a lithium-sulfur battery of claim 2 , wherein the quinone-based compound is one or more types selected from the group consisting of 1,2-benzoquinone, 1,4-benzoquinone, 1,2-naphthoquinone, 1,4-naphthoquinone, 9,10-anthraquinone, 1,4-anthraquinone, acenaphthoquinone and derivatives thereof.

4 . The electrolyte solution for a lithium-sulfur battery of claim 2 , wherein the N-oxyl radical-based compound is one or more types selected from the group consisting of 2,2,6,6-tetramethyl-1-piperidinyloxyl, 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxyl, 4-oxo-2,2,6,6-tetramethyl-1-piperidinyloxyl, 4-amino-2,2,6,6-tetramethyl-1-piperidinyloxyl, 4-acetamido-2,2,6,6-tetramethyl-1-piperidinyloxyl, 4-methoxy-2,2,6,6-tetramethyl-1-piperidinyloxyl and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxyl-benzoate.

5 . The electrolyte solution for a lithium-sulfur battery of claim 2 , wherein the amine-based compound is simazine, N1,N4-diphenylbenzene-1,4-diamine, or combinations thereof.

6 . The electrolyte solution for a lithium-sulfur battery of claim 1 , wherein the radical adsorbent is included in 0.01% to 5% by weight based on 100% by weight of the electrolyte solution.

7 . The electrolyte solution for a lithium-sulfur battery of claim 1 , wherein the non-aqueous solvent is one or more types selected from the group consisting of carbonate-based solvents, ester-based solvents, ether-based solvents, ketone-based solvents, alcohol-based solvents and aprotic solvents.

8 . The electrolyte solution for a lithium-sulfur battery of claim 1 , wherein the lithium salt includes one type selected from the group consisting of LiCl, LiBr, LiI, LiClO 4 , LiBF 4 , LiB 10 Cl 10 , LiPF 6 , LiCF 3 SO 3 , LiCF 3 CO 2 , LiC 4 BO 8 , LiAsF 6 , LiSbF 6 , LiAlCl 4 , CH 3 SO 3 Li, CF 3 SO 3 Li, (CF 3 SO 2 ) 2 NLi, (C 2 F 5 SO 2 ) 2 NLi, (SO 2 F) 2 NLi, (CF 3 SO 2 ) 3 CLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenylborate, lithium imide and combinations thereof.

9 . The electrolyte solution for a lithium-sulfur battery of claim 1 , wherein the lithium salt is included in a concentration of 0.2 M to 2.0 M.

10 . The electrolyte solution for a lithium-sulfur battery of claim 1 , further comprising an additive having N—O bonds in a molecule.

11 . The electrolyte solution for a lithium-sulfur battery of claim 10 , wherein the additive is one or more types selected from the group consisting of lithium nitrate, potassium nitrate, cesium nitrate, barium nitrate, ammonium nitrate, lithium nitrite, potassium nitrite, cesium nitrite, ammonium nitrite, methyl nitrate, dialkyl imidazolium nitrate, guanidine nitrate, imidazolium nitrate, pyridinium nitrate, ethyl nitrite, propyl nitrite, butyl nitrite, pentyl nitrite, octyl nitrite, nitromethane, nitropropane, nitrobutane, nitrobenzene, dinitrobenzene, nitropyridine, dinitropyridine, nitrotoluene, dinitrotoluene, pyridine N-oxide, alkylpyridine N-oxide and tetramethylpiperidinyloxyl.

12 . The electrolyte solution for a lithium-sulfur battery of claim 10 , wherein the additive is included in 0.01% to 10% by weight based on 100% by weight of the electrolyte solution.

13 . A lithium-sulfur battery comprising:
a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; and an electrolyte solution, wherein the electrolyte solution is the electrolyte solution of claim 1 .

Assignees

• Lg Chemical Ltd

Inventors

• Park In Tae
• Hong Sung Won
• Song Charles Kiseok
• Lee Chang Hoon
• Yang Doo Kyung

Classifications

• H01M10/4235

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

• H01M10/0567

  characterised by the additives · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M4/38

  of elements or alloys · CPC title

• H01M10/52 Primary

  Removing gases inside the secondary cell, e.g. by absorption (vent plugs or other mechanical arrangements for facilitating escape of gases H01M50/30) · CPC title