Electrolyte additive for lithium battery, electrolyte including the additive, and lithium battery including the electrolyte

Patent metadata

Field	Value
Publication number	US-10003102-B2
Application number	US-201514705819-A
Country	US
Kind code	B2
Filing date	May 6, 2015
Priority date	Jul 16, 2014
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

An electrolyte additive for a lithium battery, an electrolyte including the electrolyte additive, and a lithium battery including the electrolyte additive are disclosed. The electrolyte additive for a lithium battery includes a sulfonylmethylisocyanide-based compound. The electrolyte additive including the sulfonylmethylisocyanide-based compound may form a protective layer having improved high-temperature stability on positive and negative electrodes of a lithium battery, thereby improving the safety of the lithium battery.

First claim

What is claimed is:

1. An electrolyte for a lithium battery, the electrolyte comprising:
a lithium salt;
a nonaqueous organic solvent; and
an electrolyte additive comprising a sulfonylmethylisocyanide-based compound represented by Formula 1:

wherein, in Formula 1, R 1 is a substituted or unsubstituted C1-C20 alkyl group; a substituted or unsubstituted C1-C20 alkoxy group; a substituted or unsubstituted C2-C20 alkenyl group; a substituted or unsubstituted C2-C20 alkenyloxy group; a substituted or unsubstituted C4-C20 cycloalkyl group; a substituted or unsubstituted C4-C20 cycloalkenyl group; a substituted or unsubstituted C2-C20 alkynyl group; or a substituted or unsubstituted C6-C20 aryl group, and R 2 is a substituted or unsubstituted aliphatic, alicyclic, or aromatic hydrocarbon group,
wherein the substituted C1-C20 alkyl group; the substituted C1-C20 alkoxy group; the substituted C2-C20 alkenyl group; the substituted C2-C20 alkenyloxy group; the substituted C4-C20 cycloalkyl group; the substituted C4-C20 cycloalkenyl group; the substituted C2-C20 alkynyl group; the substituted C6-C20 aryl group, the substituted aliphatic hydrocarbon group, the substituted alicyclic hydrocarbon group, and the substituted aromatic hydrocarbon group are substituted with a substituent comprising:
a halogen atom; an amino group; a cyano group; a nitro group; a halogen-substituted or unsubstituted C1-C8 alkyl group; a halogen-substituted or unsubstituted C1-C8 alkoxy group; a halogen-substituted or unsubstituted C2-C8 alkenyl group; a halogen-substituted or unsubstituted C2-C8 alkenyloxy group; a halogen-substituted or unsubstituted C2-C8 alkynyl group; a halogen-substituted or unsubstituted C4-C10 cycloalkyl group; a halogen-substituted or unsubstituted C3-C10 cycloalkoxy group; a halogen-substituted or unsubstituted C4-C10 cycloalkenyl group; a halogen-substituted or unsubstituted C2-C10 heterocycloalkyl group; a halogen-substituted or unsubstituted C6-C10 aryl group; a halogen-substituted or unsubstituted C6-C10 aryloxy group; or a halogen-substituted or unsubstituted C6-C10 heteroaryl group, and
wherein an amount of the electrolyte additive in the electrolyte is about 0.01 parts to about 10 parts by weight based on 100 parts by weight of the nonaqueous organic solvent.

2. The electrolyte of claim 1 , wherein the electrolyte further comprises at least one other additive selected from the group consisting of tris(trimethylsilyl) phosphate (TMSPa), lithium difluorooxalate borate (LiFOB), vinylene carbonate (VC), fluoroethylene carbonate (FEC), vinyl ethylene carbonate (VEC), propane sultone (PS), succinonitrile (SN), LiBF 4 , a silane compound having a functional group able to form a siloxane bond, a silazane compound, and mixtures thereof.

3. The electrolyte of claim 1 , wherein R 1 is a substituted or unsubstituted C6-C20 aryl group.

4. The electrolyte of claim 1 , wherein the aliphatic hydrocarbon group of R 2 is a C1-C20 alkyl group, a C1-C20 alkoxy group, a C2-C20 alkenyl group, a C2-C20 alkenyloxy group; or a C2-C20 alkynyl group,
the alicyclic hydrocarbon group of R 2 is a C4-C20 cycloalkyl group; a C4-C20 cycloalkenyl group; or a C2-C20 heterocycloalkyl group, and
the aromatic hydrocarbon group is a C6-C20 aryl group or a C2-C20 heteroaryl group.

5. The electrolyte of claim 1 , wherein R 2 is a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a sec-butyl group, a vinyl group, an allyl group, a butenyl group, a pentenyl group, an ethynyl group, a propynyl group, a butynyl group, a pentynyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a phenyl group, a naphthyl group, a pyridinyl group, or a thiophenyl group.

6. The electrolyte of claim 1 , wherein the sulfonylmethylisocyanide-based compound comprises a compound represented by Formula 3 below:

wherein, in Formula 3, R 2 is as defined with respect to Formula 1.

7. The electrolyte of claim 1 , wherein the sulfonylmethylisocyanide-based compound comprises at least one of compounds represented by Formula 4 to Formula 13 below:

8. A lithium battery comprising:
a positive electrode;
a negative electrode; and
the electrolyte of claim 1 .

Assignees

• Samsung Sdi Co Ltd

Inventors

• Cho Erang
• Kim Duckhyun
• Kim Moonsung
• Lee Jeonghye
• Shin Woocheol

Classifications

• C07D333/24

  Radicals substituted by carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals · CPC title

• C07C2601/08

  the ring being saturated · CPC title

• H01M6/168

  by additives · CPC title

• C07C317/28

  with sulfone or sulfoxide groups bound to acyclic carbon atoms of the carbon skeleton · CPC title

• H01M10/052

  Li-accumulators · CPC title