Rechargeable lithium battery

Patent metadata

Field	Value
Publication number	US-2016190644-A1
Application number	US-201514940078-A
Country	US
Kind code	A1
Filing date	Nov 12, 2015
Priority date	Dec 26, 2014
Publication date	Jun 30, 2016
Grant date	—

Abstract

A rechargeable lithium battery includes: a positive electrode including a positive active material; and an electrolyte solution including a solvent and an additive, wherein the positive active material includes a lithium-containing transition metal oxide, the solvent includes a hydrofluoroether, and the additive includes a first additive represented by Chemical Formula 1 and at least one selected from a second additive represented by Chemical Formula 2, a third additive represented by Chemical Formula 3, and a fourth additive represented by Chemical Formula 4.

First claim

What is claimed is:

1 . A rechargeable lithium battery, comprising:
a positive electrode comprising a positive active material; and an electrolyte solution comprising a solvent and an additive, wherein the positive active material comprises a lithium-containing transition metal oxide, the solvent comprises hydrofluoroether, and the additive comprises:
a first additive represented by Chemical Formula 1, and
at least one selected from a second additive represented by Chemical Formula 2, a third additive represented by Chemical Formula 3, and a fourth additive represented by Chemical Formula 4:

wherein, in Chemical Formula 1,
R 1 to R 3 are each independently selected from a C1 to C8 alkyl group substituted or unsubstituted with a vinyl group or a C1 to C5 alkyl group and not including a double bond, a C1 to C8 alkyl group substituted or unsubstituted with a vinyl group or a C1 to C5 alkyl group and including a double bond, a C2 to C8 alkenyl group, a C5 to C8 cycloalkyl group, a C6 to C8 aryl group, and a fluorine atom, and
R 4 is selected from a C1 to C8 alkylene group, a C2 to C8 alkynylene group, a C4 to C8 alkylene group having at least one selected from an ether group and a thioether group a C1 to C8 alkylene group having a plurality of —CF 2 — linking groups, and a C4 to C10 alkylene group having an ether group and a thioether group,

wherein, in Chemical Formula 2,
R 5 is selected from a C2 to C6 alkylene group without a double bond, a C2 to C6 alkylene group with a double bond, and a C6 to C12 arylene group, and
R 6 to R 11 are each independently selected from a C1 to C6 alkyl group and a C2 to C6 alkenyl group,

wherein, in Chemical Formula 3,
R 12 and R 13 are each independently selected from hydrogen and a C1 to C8 alkyl group, and
R 14 is selected from a C1 to C8 alkyl group substituted or unsubstituted with a vinyl group, a C2 to C8 alkenyl group, a C2 to C8 alkynyl group, and a C1 to C8 halogenated alkyl group,

wherein, in Chemical Formula 4,
R 15 and R 16 are each independently selected from hydrogen and a C1 to C8 alkyl group,
R 17 is selected from a C1 to C8 alkyl group, a C2 to C8 alkenyl group, a C2 to C8 alkynyl group, and a C1 to C8 halogenated alkyl group, and
n is 1 or 2.

2 . The rechargeable lithium battery of claim 1 , wherein the hydrofluoroether comprises 2,2,2-trifluoroethylmethylether (CF 3 CH 2 OCH 3 ), 2,2,2-trifluoroethyldifluoromethylether (CF 3 CH 2 OCHF 2 ), 2,2,3,3,3-pentafluoropropylmethylether (CF 3 CF 2 CH 2 OCH 3 ), 2,2,3,3,3-pentafluoropropyldifluoromethylether (CF 3 CF 2 CH 2 OCHF 2 ), 2,2,3,3,3-pentafluoropropyl-1,1,2,2-tetrafluoroethylether (CF 3 CF 2 CH 2 OCF 2 CF 2 H), 1,1,2,2-tetrafluoroethylmethylether (HCF 2 CF 2 OCH 3 ), 1,1,2,2-tetrafluoroethylethylether (HCF 2 CF 2 OCH 2 CH 3 ), 1,1,2,2-tetrafluoroethylpropylether (HCF 2 CF 2 OC 3 H 7 ), 1,1,2,2-tetrafluoroethylbutylether (HCF 2 CF 2 OC 4 H 9 ), 2,2,3,3-tetrafluoroethyldifluoromethylether (H(CF 2 ) 2 CH 2 O(CF 2 )H), 1,1,2,2-tetrafluoroethylisobutylether (HCF 2 CF 2 OCH 2 CH(CH 3 ) 2 ), 1,1,2,2-tetrafluoroethylisopentylether (HCF 2 CF 2 OCH 2 C(CH 3 ) 3 ), 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethylether (HCF 2 CF 2 OCH 2 CF 3 ), 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether (HCF 2 CF 2 OCH 2 CF 2 CF 2 H), hexafluoroisopropylmethylether ((CF 3 ) 2 CHOCH 3 ), 1,1,3,3,3-pentafluoro-2-trifluoromethylpropylmethylether ((CF 3 ) 2 CHCF 2 OCH 3 ), 1,1,2,3,3,3-hexafluoropropylmethylether (CF 3 CHFCF 2 OCH 3 ), 1,1,2,3,3,3-hexafluoropropylethylether (CF 3 CHFCF 2 OCH 2 CH 3 ), 2,2,3,4,4,4-hexafluorobutyldifluoromethylether (CF 3 CHFCF 2 CH 2 OCHF 2 ), or a mixture thereof.

3 . The rechargeable lithium battery of claim 1 , wherein the hydrofluoroether is included in an amount of about 10 to about 60 volume % based on the total volume of the solvent.

4 . The rechargeable lithium battery of claim 1 , wherein the first additive is included in an amount of about 0.01 to about 1.5 wt % based on the total weight of the electrolyte solution.

5 . The rechargeable lithium battery of claim 4 , wherein the additive comprises the first additive and the second additive, and
the second additive is included in an amount of about 0.05 to about 1.00 wt % based on the total weight of the electrolyte solution.

6 . The rechargeable lithium battery of claim 4 , wherein the additive comprises the first additive and the third additive, and
the third additive is included in an amount of about 0.04 to about 1.00 wt % based on the total weight of the electrolyte solution.

7 . The rechargeable lithium battery of claim 4 , wherein the additive comprises the first additive and the fourth additive, and
the fourth additive is included in an amount of about 0.01 to about 1.00 wt % based on the total weight of the electrolyte solution.

8 . The rechargeable lithium battery of claim 1 , wherein the first additive comprises at least one selected from compounds represented by Chemical Formulae 1-1 to 1-9:

9 . The rechargeable lithium battery of claim 1 , wherein the second additive is selected from a compound represented by Chemical Formula 2-1, a compound represented by Chemical Formula 2-2, and mixtures thereof:

10 . The rechargeable lithium battery of claim 1 , wherein the third additive comprises at least one selected from compounds represented by Chemical Formulae 3-1 to 3-8:

11 . The rechargeable lithium battery of claim 1 , wherein the fourth additive comprises at least one selected from compounds represented by Chemical Formulae 4-1 to 4-4:

12 . The rechargeable lithium battery of claim 1 , wherein the lithium-containing transition metal oxide is a lithium cobalt-based composite oxide.

13 . The rechargeable lithium battery of claim 1 , wherein the rechargeable lithium battery further comprises a negative electrode including a negative active material, and
wherein the negative active material comprises at least one selected from a carbon-based material, a silicon-based material, a tin-based material, a lithium metal oxide, and a metal lithium.

14 . The rechargeable lithium battery of claim 1 , wherein the solvent further comprises fluoroethylene carbonate.

15 . The rechargeable lithium battery of claim 14 , wherein the fluoroethylene carbonate is included in an amount of about 10 to about 30 volume % based on the total volume of the solvent.

16 . The rechargeable lithium battery of claim 1 , wherein an oxidation-reduction potential of the rechargeable lithium battery is greater than or equal to about 4.3 V (vs. Li/Li + ) and less than or equal to about 5.0 V.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Takase Hironari
• Yokotsuji Hokuto

Classifications

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M2220/30

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