Electrolyte, and secondary battery and electric apparatus containing same

Patent metadata

Field	Value
Publication number	US-2025070258-A1
Application number	US-202418946735-A
Country	US
Kind code	A1
Filing date	Nov 13, 2024
Priority date	Jan 4, 2023
Publication date	Feb 27, 2025
Grant date	—

Abstract

An electrolyte includes a solvent, where the solvent includes at least one cyclic ether of formula (I) and at least one linear ether of formula (II).

where A 1 is an oxygen atom, a single bond, or CHR 4 , A 2 is an oxygen atom or CHR 5 , A 2 is different from A 1 , and when A 1 is CHR 4 , A 2 is not CHR 5 , R 1 , R 2 , and R 5 are each independently a hydrogen atom, C1-6 alky, or C1-6 fluoroalkyl, R 3 and R 4 are each independently a hydrogen atom, a fluorine atom, C1-6 alkyl, or C1-6 fluoroalkyl, R 1 to R 5 comprise 1 to 3 fluorine atom, R 6 is a hydrogen atom, a fluorine atom, C1-6 alkyl, or C1-6 fluoroalkyl, and R 7 is a hydrogen atom, C1-6 alkyl, or C1-6 fluoroalkyl

First claim

What is claimed is:

1 . An electrolyte, comprising a solvent, wherein the solvent comprises at least one cyclic ether of formula (I) and at least one linear ether of formula (II);
wherein the cyclic ether of formula (I) has the following structure:

 wherein:
A 1 is an oxygen atom, a single bond, or CHR 4 ,
A 2 is an oxygen atom or CHR 5 ,
A 2 is different from A 1 , and when A 1 is CHR 4 , A 2 is not CHR 5 ,
R 1 , R 2 , and R 5 are each independently a hydrogen atom, C1-6 alky, or C1-6 fluoroalkyl,
R 3 and R 4 are each independently a hydrogen atom, a fluorine atom, C1-6 alkyl, or C1-6 fluoroalkyl, and
R 1 to R 5 comprise 1 to 3 fluorine atoms; and

the linear ether of formula (II) has the following structure:

 wherein:
R 6 is a hydrogen atom, a fluorine atom, C1-6 alkyl, or C1-6 fluoroalkyl, and
R 7 is a hydrogen atom, C1-6 alkyl, or C1-6 fluoroalkyl.

2 . The electrolyte according to claim 1 , wherein:
R 1 , R 2 , and R 5 are each independently a hydrogen atom, C1-4 alkyl, or C1-4 fluoroalkyl, and optionally a hydrogen atom, methyl, or fluoromethyl; and/or R 3 and R 4 are each independently a hydrogen atom, a fluorine atom, C1-4 alkyl, or C1-4 fluoroalkyl, and optionally a hydrogen atom, a fluorine atom, methyl, or fluoromethyl.

3 . The electrolyte according to claim 1 , wherein one and only one of R 1 to R 5 is a fluorine-containing substituent selected from a fluorine atom or C1-6 fluoroalkyl.

4 . The electrolyte according to claim 1 , wherein the cyclic ether of formula (I) is selected from at least one of the following compounds:

5 . The electrolyte according to claim 1 , wherein:
R 6 is a hydrogen atom, a fluorine atom, C1-5 alkyl, or C1-5 fluoroalkyl, and optionally a hydrogen atom, a fluorine atom, C1-2 alkyl, or C1-2 fluoroalkyl; and/or R 7 is a hydrogen atom, C1-5 alkyl, or C1-5 fluoroalkyl, and optionally a hydrogen atom, C1-2 alkyl, or C1-2 fluoroalkyl.

6 . The electrolyte according to claim 1 , wherein a carbon atom count of at least one of R 6 and R 7 is less than 2.

7 . The electrolyte according to claim 1 , wherein the linear ether of formula (II) is selected from at least one of the following compounds:

8 . The electrolyte according to claim 1 , wherein a molar ratio of the cyclic ether to the linear ether is greater than 0.1, optionally from 0.2 to 6, more optionally from 0.2 to 5, further optionally from 0.4 to 2.5, and still further optionally from 0.8 to 1.25.

9 . The electrolyte according to claim 1 , further comprising:
an electrolytic salt, wherein the electrolytic salt is an electrolytic salt containing fluorine; optionally, the electrolytic salt is selected from one or more of the following: lithium bis(fluorosulfonyl)imide, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroarsenate, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium difluoro(bisoxalato)phosphate, and lithium tetrafluoro(oxalato)phosphate; more optionally, the electrolytic salt is selected from at least one of lithium bis(fluorosulfonyl)imide, lithium hexafluorophosphate, and lithium difluoro(oxalato)borate; and further optionally, the electrolytic salt is lithium bis(fluorosulfonyl)imide.

10 . The electrolyte according to claim 9 , wherein a concentration of the electrolytic salt is from 0.3 M to 6 M, optionally from 0.5 M to 5 M, more optionally from 1 M to 3 M, and further optionally from 1.5 M to 2.5 M.

11 . A secondary battery, comprising the electrolyte according to claim 1 .

12 . The secondary battery according to claim 11 , further comprising:
a negative electrode plate, wherein the negative electrode plate comprises a negative electrode current collector and a negative electrode film layer optionally disposed on at least one surface of the negative electrode current collector; wherein:
the negative electrode film layer is a lithium-containing metal layer or a non-lithium-containing coating;
a lithium-containing metal is a metal element of lithium or a lithium-containing alloy, and optionally, the lithium-containing alloy is an alloy formed by lithium and other metal elements or non-metal elements, wherein the metal element comprises tin (Sn), zinc (Zn), aluminum (Al), magnesium (Mg), silver (Ag), gold (Au), gallium (Ga), indium (In), platinum (Pt), and a combination thereof, and the non-metal element comprises boron (B), carbon (C), silicon (Si), and a combination thereof, and
the non-lithium-containing coating is a coating containing no lithium metal nor oxide thereof, optionally, the non-lithium-containing coating is selected from tin, zinc, aluminum, magnesium, silver, gold, gallium, indium, platinum, zinc oxide, aluminum oxide, or titanium oxide coating, optionally zinc or zinc oxide coating, and more optionally zinc coating.

13 . The secondary battery according to claim 12 , wherein a thickness of the non-lithium-containing coating is at most 200 nm, optionally from 50 nm to 200 nm, and more optionally from 50 nm to 100 nm.

14 . An electric apparatus, comprising the secondary battery according to claim 11 .

Assignees

• Contemporary Amperex Technology Hong Kong Ltd

Inventors

• Wang Hansen
• Liu Chengyong
• Wan pan
• Huang Shengyuan
• Hu Bobing
• Zhang Rupeng

Classifications

• H01M10/0569 Primary

  characterised by the solvents · CPC title

• H01M10/0525 Primary

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

• H01M2300/0034

  Fluorinated solvents · CPC title

• H01M10/0568

  characterised by the solutes · CPC title

• H01M10/052

  Li-accumulators · CPC title