Electrolyte for Lithium Secondary Battery and Lithium Secondary Battery Containing the Same

Patent metadata

Field	Value
Publication number	US-2016359196-A1
Application number	US-201615168452-A
Country	US
Kind code	A1
Filing date	May 31, 2016
Priority date	Jun 8, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

Provided are an electrolyte for a lithium secondary battery and a lithium secondary battery containing the same. The electrolyte for a secondary battery according to the present invention has excellent high-temperature stability, excellent low-temperature discharge capacity, and excellent life cycle characteristics.

First claim

What is claimed is:

1 . An electrolyte for a secondary battery comprising:
a lithium salt; a non-aqueous organic solvent; and a cyclic sulfate compound represented by the following Chemical Formula 1:

wherein, in Chemical Formula 1,
W is

L is a single bond or methylene; and
m is an integer of 1 to 4, n is an integer of 0 to 2, and p is an integer of 0 to 6.

2 . The electrolyte for a secondary battery of claim 1 , wherein the cyclic sulfate compound represented by Chemical Formula 1 is represented by the following Chemical Formulas 2 to 5:

wherein, in the Chemical Formulas, m is an integer of 1 to 4, n is an integer of 0 to 2, and p is an integer of 0 to 6.

3 . The electrolyte for a second battery of claim 2 , wherein the cyclic sulfate compound represented by Chemical Formula 3 is selected from compounds having the following structures:

4 . The electrolyte for a second battery of claim 2 , wherein the cyclic sulfate compound represented by Chemical Formula 4 is selected from compounds having the following structures:

5 . The electrolyte for a second battery of claim 1 , further comprising a cyclic sulfite compound represented by Chemical Formula 6:

wherein, in Chemical Formula 6,
W is

L is a single bond or methylene; and
m is an integer of 1 to 4, n is an integer of 0 to 2, and p is an integer of 0 to 6.

6 . The electrolyte for a secondary battery of claim 5 , wherein the cyclic sulfite compound represented by Chemical Formula 6 is represented by the following Chemical Formulas 7 to 10:

wherein, in the Chemical Formulas, m is an integer of 1 to 4, n is an integer of 0 to 2, and p is an integer of 0 to 6.

7 . The electrolyte for a secondary battery of claim 6 , wherein the cyclic sulfite compound represented by Chemical Formula 8 is selected from compounds having the following structures:

8 . The electrolyte for a secondary battery of claim 6 , wherein the cyclic sulfite compound represented by Chemical Formula 9 is selected from compounds having the following structures:

9 . The electrolyte for a secondary battery of claim 1 , wherein the cyclic sulfate compound represented by Chemical Formula 1 is contained at a content of 0.1 to 5.0 wt % based on a total weight of the electrolyte.

10 . The electrolyte for a secondary battery of claim 5 , wherein the cyclic sulfite compound represented by Chemical Formula 6 is contained at a content of 0.001 to 20 mol % based on a total mole of the cyclic sulfate compound represented by Chemical Formula 1 and the cyclic sulfite compound represented by Chemical Formula 6.

11 . The electrolyte for a secondary battery of claim 1 , further comprising one or two or more additives selected from the group consisting of oxalatoborate based compounds, carbonate based compounds substituted with fluorine, vinylidene carbonate based compounds, and compounds containing a sulfinyl group.

12 . The electrolyte for a secondary battery of claim 11 , further comprising an additive selected from the group consisting of lithium difluoro(oxalato)borate (LiFOB), lithium bis(oxalato)borate (LiB (C 2 O 4 ) 2 , LiBOB), fluoroethylene carbonate (FEC), vinylene carbonate (VC), vinylethylene carbonate (VEC), divinyl sulfone, ethylene sulfite, propylene sulfite, diallyl sulfonate, ethane sultone, propane sultone (PS), butane sultone, ethene sultone, butene sultone, and propene sultone (PRS).

13 . The electrolyte for a secondary battery of claim 11 , wherein the additive is contained at a content of 0.1 to 5.0 wt % based on a total weight of the electrolyte.

14 . The electrolyte for a secondary battery of claim 1 , wherein the non-aqueous organic solvent is selected from cyclic carbonate based solvents, linear carbonate based solvents, and a mixed solvent thereof.

15 . The electrolyte for a secondary battery of claim 14 , wherein the cyclic carbonate is selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, vinylethylene carbonate, fluoroethylene carbonate, and a mixture thereof, and the linear carbonate is selected from the group consisting of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, methyl isopropyl carbonate, ethyl propyl carbonate, and a mixture thereof.

16 . The electrolyte for a secondary battery of claim 14 , wherein the non-aqueous organic solvent is a mixed solvent in which the linear carbonate solvent and the cyclic carbonate solvent are mixed at a mixed volume ratio of 1:1 to 9:1.

17 . The electrolyte for a secondary battery of claim 1 , wherein the lithium salt is one or two or more selected from the group consisting of LiPF 6 , LiBF 4 , LiClO 4 , LiSbF 6 , LiAsF 6 , LiN(SO 2 C 2 F 5 ) 2 , LiN (CF 3 SO 2 ) 2 , LiN (SO 3 C 2 F 5 ) 2 , LiN (SO 2 F) 2 , LiCF 3 SO 3 , LiC 4 F 9 SO 3 , LiC 6 H 5 SO 3 , LiSCN, LiAlO 2 , LiAlCl 4 , LiN (C x F 2x+1 SO 2 ) (C y F 2y+1 SO 2 ) (here, x and y are natural numbers), LiCl, LiI, and LiB(C 2 O 4 ) 2 .

18 . The electrolyte for a secondary battery of claim 1 , wherein the lithium salt is contained at a concentration of 0.1 to 2.0 M.

19 . A lithium secondary battery comprising the electrolyte for a secondary battery of claim 1 .

Assignees

• Sk Innovation Co Ltd

Inventors

• Kim Jin Sung
• Kim Cheol Woo
• Oh Sung Yon
• Lee Kwang Kuk
• Lee Seong Il

Classifications

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/0568

  characterised by the solutes · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M10/0525 Primary

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

• H01M10/0567 Primary

  characterised by the additives · CPC title