Electrolyte for lithium secondary battery, and lithium secondary battery comprising same

Patent metadata

Field	Value
Publication number	US-2025132388-A1
Application number	US-202218689829-A
Country	US
Kind code	A1
Filing date	Sep 6, 2022
Priority date	Sep 7, 2021
Publication date	Apr 24, 2025
Grant date	—

Abstract

An electrolyte for a lithium secondary battery and a lithium secondary battery are disclosed. The electrolyte for a lithium secondary battery includes: a lithium salt; an organic solvent; and an additive, wherein the additive includes a compound represented by Formula 1.

First claim

1 . An electrolyte for a lithium secondary battery, comprising:
a lithium salt; an organic solvent; and an additive, wherein the additive comprises a compound represented by Formula 1:

wherein, in Formula 1,
R 1 is a substituted or unsubstituted C 1 -C 20 alkyl group, and
R 2 and R 3 are each independently selected from hydrogen, deuterium, a fluoro group (—F), a chloro group (—Cl), a bromo group (—Br), an iodo group (—I), a hydroxyl group, a cyano group, a nitro group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a substituted or unsubstituted C 1 -C 20 alkyl group, a substituted or unsubstituted C 2 -C 20 alkenyl group, a substituted or unsubstituted C 2 -C 20 alkynyl group, a substituted or unsubstituted C 1 -C 20 alkoxy group, a substituted or unsubstituted C 3 -C 20 cycloalkyl group, a substituted or unsubstituted C 2 -C 20 heterocycloalkyl group, a substituted or unsubstituted C 3 -C 20 cycloalkenyl group, a substituted or unsubstituted C 2 -C 20 heterocycloalkenyl group, a substituted or unsubstituted C 6 -C 20 aryl group, a substituted or unsubstituted C 6 -C 20 aryloxy group, a substituted or unsubstituted C 6 -C 20 arylthio group, a substituted or unsubstituted C 2 -C 20 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —N(Q 1 )(Q 2 ), and —B(Q 6 )(Q 7 ), wherein Q 1 to Q 7 are each independently selected from hydrogen, a C 1 -C 20 alkyl group, a C 2 -C 20 alkenyl group, a C 2 -C 20 alkynyl group, a C 1 -C 20 alkoxy group, a C 3 -C 20 cycloalkyl group, a C 2 -C 20 heterocycloalkyl group, a C 3 -C 20 cycloalkenyl group, a C 2 -C 20 heterocycloalkenyl group, a C 6 -C 20 aryl group, a C 6 -C 20 aryloxy group, a C 6 -C 20 arylthio group, a C 2 -C 20 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group.

2 . The electrolyte of claim 1 , wherein, in Formula 1, R 1 is an unsubstituted C 1 -C 20 alkyl group, and
R 2 and R 3 are each independently hydrogen or an unsubstituted C 1 -C 20 alkyl group.

3 . The electrolyte of claim 1 , wherein, in Formula 1, R 1 is an unsubstituted linear or branched C 1 -C 20 alkyl group.

4 . The electrolyte of claim 1 , wherein the additive comprises a compound represented by Formula 2:

wherein, in Formula 2,
R 1 is a substituted or unsubstituted C 1 -C 20 alkyl group.

5 . The electrolyte of claim 1 , wherein the additive comprises at least one of compounds represented by Formulae 3 to 6:

6 . The electrolyte of claim 1 , wherein an amount of the compound is in a range of about 0.001 parts by weight to about 20 parts by weight based on 100 parts by weight of an electrolyte solution consisting of the lithium salt and the organic solvent.

7 . The electrolyte of claim 1 , wherein the electrolyte further comprises other additives, and the other additives comprise at least one of vinylene carbonate (VC), fluoroethylene carbonate (FEC), difluoroethylene carbonate (DFEC), chloroethylene carbonate (CEC), dichloroethylene carbonate (DCEC), bromoethylene carbonate (BEC), dibromoethylene carbonate (DBEC), nitroethylene carbonate, cyanoethylene carbonate, vinylethylene carbonate (VEC), succinonitrile (SN), adiponitrile (AN), 1,3,6-hexane tricyanide (HTCN), prophene sultone (PST), propanesultone (PS), lithium tetrafluoroborate (LiBF 4 ), lithium difluorophosphate (LiPO 2 F 2 ), and 2-fluoro biphenyl(2-FBP).

8 . The electrolyte of claim 7 , wherein an amount of the other additives is in a range of about 0.2 parts by weight to about 20 parts by weight based on 100 parts by weight of an electrolyte solution consisting of the lithium salt and the organic solvent.

9 . A lithium secondary battery comprising:
a cathode comprising a cathode active material layer; an anode comprising an anode active material layer; and the electrolyte according to claim 1 disposed between the cathode and the anode.

10 . The lithium secondary battery of claim 9 , wherein the cathode active material comprises a lithium transition metal oxide comprising nickel and other transition metals, and an amount of the nickel in the lithium transition metal oxide is greater than or equal to about 60 mol % and less than about 100 mol % based on the total number of moles of the transition metals.

11 . The lithium secondary battery of claim 9 , wherein the cathode active material comprises a compound represented by Formula 11:
Li a Ni x Co y M z O 2-b A b   Formula 11
wherein, in Formula 11, 1.0≤a≤1.2, 0≤b≤0.2, 0.6≤x<1, 0<y≤0.4, 0<z≤0.4, x+y+z=1, M is at least one selected from the group consisting of manganese (Mn), vanadium (V), magnesium (Mg), gallium (Ga), silicon (Si), tungsten (W), molybdenum (Mo), iron (Fe), chromium (Cr), copper (Cu), zinc (Zn), titanium (Ti), aluminum (Al), and boron (B), and A is F, S, Cl, Br, or a combination thereof.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Lee Taejin
• Kim Dahyun
• Kim Minseo
• Woo Myungheui
• Kim Sanghoon
• Kim Sanghyung
• Park Hyejin
• Ryu Bokyung

Classifications

• H01M10/0525

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

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M10/0567 Primary

  characterised by the additives · 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