Electrolyte for lithium secondary battery and lithium secondary battery employing the same

Patent metadata

Field	Value
Publication number	US-10050305-B2
Application number	US-201414543630-A
Country	US
Kind code	B2
Filing date	Nov 17, 2014
Priority date	Dec 16, 2013
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

In an aspect, an electrolyte for a lithium secondary battery that includes a compound represented by Formula 1, a nonaqueous organic solvent, and a lithium salt, and a lithium secondary battery including the electrolyte are provided.

First claim

What is claimed is:

1. An electrolyte for a lithium secondary battery, comprising:
a compound represented by Formula 1:

wherein, in Formula 1, R 1 , R 2 and R 3 are each independently an unsubstituted C1-C30 alkyl group, an unsubstituted C1-C30 alkoxy group, an unsubstituted C2-C30 alkenyl group, an unsubstituted C2-C30 alkynyl group, a unsubstituted C6-C30 aryl group, an unsubstituted C6-C30 aryloxy group, an unsubstituted C7-C30 arylalkyl group, an unsubstituted C1-C30 heteroaryl group, an unsubstituted C1-C30 heteroaryloxy group, an unsubstituted C2-C30 heteroarylalkyl group, an unsubstituted C4-C30 carbon ring group, an unsubstituted C4-C30 carbocyclic alkyl group, an unsubstituted C2-C30 heterocyclic group, an unsubstituted C2-C30 heterocyclic alkyl group, a cyano group, a halogen atom, a hydroxy group, a hydrazine, or a hydrazone, and
X is an oxygen (O) or a sulfur (S);
a nonaqueous organic solvent;
fluoroethylene carbonate (FEC), vinylene carbonate (VC), and succinonitrile (SN); and
a lithium salt,
wherein an amount of the compound represented by Formula 1 is in a range of about 0.5 wt % to about 5 wt % based on total amount of the electrolyte; and
the nonaqueous organic solvent is a mixture of dimethyl carbonate (DMC), methylethyl carbonate (MEC), and ethylene carbonate (EC).

2. The electrolyte of claim 1 , wherein R 1 to R 3 in Formula 1 are independently an unsubstituted C6-C30 aryl group or an unsubstituted C1-C30 alkyl group.

3. The electrolyte of claim 1 , wherein the compound represented by Formula 1 is a compound represented by Formula 2 or a compound represented by Formula 3:

4. The electrolyte of claim 1 , wherein the lithium salt is at least one selected from LiPF 6 , LiBF 4 , LiSbF 6 , LiAsF 6 , LiC 4 F 9 SO 3 , LiClO 4 , LiAlO 2 , LiAlCl 4 , LiN(C x F 2x+1 SO 2 )(C y F 2y+1 SO 2 ) (where x and y are natural numbers of 1 to 20, respectively), LiCl, LiI, and LiB(C 2 O 4 ) 2 (lithium bis(oxalato)borate).

5. The electrolyte of claim 1 , wherein a concentration of the lithium salt is in a range of about 0.1M to about 2.0M.

6. A lithium secondary battery comprising:
a positive electrode;
a negative electrode;
a separator; and
an electrolyte comprising a compound represented by Formula 1, a nonaqueous organic solvent, fluoroethylene carbonate (FEC), vinylene carbonate (VC), succinonitrile (SN), and a lithium salt, and a reaction product of the electrolyte,

wherein, in Formula 1, R 1 , R 2 and R 3 are each independently an unsubstituted C1-C30 alkyl group, an unsubstituted C1-C30 alkoxy group, an unsubstituted C2-C30 alkenyl group, an unsubstituted C2-C30 alkynyl group, an unsubstituted C6-C30 aryl group, an unsubstituted C6-C30 aryloxy group, an unsubstituted C7-C30 arylalkyl group, an unsubstituted C1-C30 heteroaryl group, an unsubstituted C1-C30 heteroaryloxy group, an unsubstituted C2-C30 heteroarylalkyl group, an unsubstituted C4-C30 carbon ring group, an unsubstituted C4-C30 carbocyclic alkyl group, an unsubstituted C2-C30 heterocyclic group, an unsubstituted C2-C30 heterocyclic alkyl group, a cyano group, a halogen atom, a hydroxy group, a hydrazine, or a hydrazone; and
X is an oxygen (O) or a sulfur (S),
wherein an amount of the compound represented by Formula 1 is in a range of about 0.5 wt % to about 5 wt % based on total amount of the electrolyte; and
the lithium salt is a mixture of LiPF 6 and LiBF 4 .

7. The lithium secondary battery of claim 6 , wherein R 1 to R 3 in Formula 1 are each independently an unsubstituted C6-C30 aryl group or an unsubstituted C1-C30 alkyl group.

8. The lithium secondary battery of claim 6 , wherein the compound represented by Formula 1 is a compound represented by Formula 2 or a compound represented by Formula 3:

9. The lithium secondary battery of claim 6 , wherein the nonaqueous organic solvent comprises at least one selected from a carbonate-based solvent, an ester-based solvent, an ether-based solvent, a ketone-based solvent, an alcohol-based solvent, and an aprotic solvent.

10. The lithium secondary battery of claim 6 , wherein the nonaqueous organic solvent is a mixture of dimethyl carbonate (DMC), methylethyl carbonate (MEC), and ethylene carbonate (EC).

11. The lithium secondary battery of claim 6 , wherein a concentration of the lithium salt is in a range of about 0.1M to about 2.0M.

12. An electrolyte for a lithium secondary battery, comprising: a compound represented by Formula 1:

wherein, in Formula 1, R 1 , R 2 and R 3 are each independently an unsubstituted C1-C30 alkyl group, and X is an oxygen (O) or a sulfur (S);
a nonaqueous organic solvent; and
a lithium salt,
wherein an amount of the compound represented by Formula 1 is in a range of about 0.5 wt % to about 5 wt % based on total amount of the electrolyte.

13. The electrolyte of claim 12 , the compound represented by Formula 1 is a compound represented by Formula 3:

14. A lithium secondary battery comprising:
a positive electrode; a negative electrode; a separator; and
an electrolyte comprising a compound represented by Formula 1, a nonaqueous organic solvent, and a lithium salt, and a reaction product of the electrolyte:

wherein, in Formula 1, R 1 , R 2 and R 3 are each independently an unsubstituted C1-C30 alkyl group, and X is an oxygen (O) or a sulfur (S),
and wherein an amount of the compound represented by Formula 1 is in a range of about 0.5 wt % to about 5 wt % based on total amount of the electrolyte.

15. The lithium secondary battery of claim 14 , the compound represented by Formula 1 is a compound represented by Formula 3:

Assignees

• Samsung Sdi Co Ltd

Inventors

• Kim Moon-Sung
• Kim Duck-Hyun
• Cho E-Rang
• Lee Jeong-Hye

Classifications

• H01M10/052

  Li-accumulators · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M2300/0028

  characterised by the solvent · CPC title

• H01M10/0568

  characterised by the solutes · CPC title