Electrolytic solution, electrochemical device containing same, and electronic device

Patent metadata

Field	Value
Publication number	US-2024234815-A1
Application number	US-202418606708-A
Country	US
Kind code	A1
Filing date	Mar 15, 2024
Priority date	Sep 16, 2021
Publication date	Jul 11, 2024
Grant date	—

Abstract

An electrolytic solution, an electrochemical device containing the electrolytic solution, and an electronic device. The electrolytic solution includes ethylene carbonate, propylene carbonate, and fluoroethylene carbonate. Based on a mass of the electrolytic solution, a mass percent of the ethylene carbonate is a, a mass percent b of the propylene carbonate is 12% to 35%, a mass percent c of the fluoroethylene carbonate is 0.2% to 2.5%, and the electrolytic solution satisfies 0.1≤a/b≤0.75.

First claim

What is claimed is:

1 . An electrolytic solution, comprising ethylene carbonate, propylene carbonate, and fluoroethylene carbonate; wherein, based on a mass of the electrolytic solution, a mass percent of the ethylene carbonate is a, a mass percent b of the propylene carbonate is 12% to 35%, a mass percent c of the fluoroethylene carbonate is 0.2% to 2.5%, and 0.1≤a/b≤0.75.

2 . The electrolytic solution according to claim 1 , wherein 1.0%≤a≤20%.

3 . The electrolytic solution according to claim 1 , further comprising an additive A, wherein the additive A comprises at least one selected from the group consisting of vinylene carbonate, vinyl ethylene carbonate, ethylene sulfate, lithium difluorophosphate, and a lithium borate salt.

4 . The electrolytic solution according to claim 3 , wherein the electrolytic solution satisfies at least one of the following conditions:
(a) the additive A comprises vinylene carbonate, wherein, based on the mass of the electrolytic solution, a mass percent A1 of the vinylene carbonate is 0.01% to 2%; (b) the additive A comprises ethylene sulfate, wherein, based on the mass of the electrolytic solution, a mass percent A2 of the ethylene sulfate is 0.01% to 2%; (c) the additive A comprises a lithium borate salt, the lithium borate salt comprises at least one selected from the group consisting of lithium tetrafluoroborate, lithium difluoro(oxalato)borate, and lithium bis(oxalato)borate; wherein, based on the mass of the electrolytic solution, a mass percent A3 of the lithium borate salt is 0.01% to 2%; (d) the electrolytic solution comprises vinylene carbonate and ethylene sulfate, wherein, based on the mass of the electrolytic solution, the mass percent of the vinylene carbonate is A1, the mass percent of the ethylene sulfate is A2, 0.1<A2/A1≤12; (e) the electrolytic solution comprises vinylene carbonate and ethylene sulfate, wherein, based on the mass of the electrolytic solution, the mass percent of the vinylene carbonate is A1, the mass percent of the ethylene sulfate is A2, 0.02%≤A1+A2≤3%; (f) the electrolytic solution comprises vinylene carbonate and a lithium borate salt, wherein, based on the mass of the electrolytic solution, the mass percent of the vinylene carbonate is A1, the mass percent of the lithium borate salt is A3, 0.01%≤A1+A3≤3%; or (g) the electrolytic solution comprises vinylene carbonate and a lithium borate salt, wherein, based on the mass of the electrolytic solution, the mass percent of the vinylene carbonate is A1, the mass percent of the lithium borate salt is A3, 0.1≤A1/A3≤10.

5 . The electrolytic solution according to claim 1 , wherein the electrolytic solution satisfies at least one of the following conditions:
(h) the electrolytic solution further comprises an additive B, wherein, based on the mass of the electrolytic solution, a mass percent of the additive B is 0.5% to 4% and the additive B comprises at least one selected from the group consisting of succinonitrile, adiponitrile, 1,4-dicyano-2-butene, ethylene glycol bis(propionitrile)ether, 1,3,6-hexane tricarbonitrile, and 1,2,3-tris(2-cyanooxy)propane; (i) the electrolytic solution further comprises a compound represented by Formula (I):

wherein, R is selected from unsubstituted or Ra-substituted C 1 to C 8 fluoroalkyls, unsubstituted or Ra-substituted C 2 to C 10 fluoroalkenyl, or unsubstituted or Ra-substituted C 6 to C 10 fluoroaryl,
a substituent Ra of each group independently comprises at least one of a cyano group, a carboxyl group, or a sulfate group,
wherein, based on the mass of the electrolytic solution, a mass percent g of the compound represented by Formula (I) is 0.01% to 2%;
(j) the electrolytic solution further comprises at least one of compounds represented by Formula I-1 to Formula I-9:

(k) the electrolytic solution further comprises a chain carbonate, wherein, based on the mass of the electrolytic solution, a mass percent of the chain carbonate is d; the chain carbonate comprises at least one selected from the group consisting of dimethyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, methyl isopropyl carbonate, methyl butyl carbonate, diethyl carbonate, dipropyl carbonate, and dibutyl carbonate; 0.04≤a/d≤0.35 or 30%≤d≤60%; or
(l) the electrolytic solution further comprises a sultone compound, wherein the sultone compound comprises at least one selected from the group consisting of 1,3-propane sultone, 2,4-butane sultone, and 1,4-butane sultone; wherein, based on the mass of the electrolytic solution, a mass percent e of the sultone compound is 0.5% to 5%, and c≤e.

6 . An electrochemical device compriseing the electrolytic solution, wherein the electrolytic solution comprises ethylene carbonate, propylene carbonate, and fluoroethylene carbonate, wherein, based on a mass of the electrolytic solution, a mass percent of the ethylene carbonate is a, a mass percent b of the propylene carbonate is 12% to 35%, a mass percent c of the fluoroethylene carbonate is 0.2% to 2.5%, 0.1≤a/b≤0.75.

7 . The electrochemical device according to claim 6 , wherein the electrochemical device further comprises a positive electrode plate, the positive electrode plate comprises a positive material layer, the positive material layer comprises a positive active material, and a particle diameter of the positive active material satisfies 0.4 μm≤D v50 ≤20 μm, and 2 μm≤D v90 ≤40 μm.

8 . The electrochemical device according to claim 7 , wherein the D v50 of the positive active material is f μm, and the electrochemical device satisfies at least one of conditions (i) to (iii):

0
.
0

⁢
5

≤

c
/
f
×
100

≤
1

;

(
i
)

(ii) the electrolytic solution comprises a sultone compound, and, based on a mass of the electrolytic solution, a mass percent of the sultone compound is e, and 0.08≤e/f×100≤3; or
(iii) the electrolytic solution comprises a compound represented by Formula (I), and, based on the mass of the electrolytic solution, a mass percent of the compound represented by Formula (I) is g, and 0.02≤g/f×100≤1.

9 . The electrochemical device according to claim 7 , wherein the positive active material comprises element M, the element M comprises at least one of Al, Mg, Ti, Cr, B, Fe, Zr, Y, Na, W, F, or S; and, based on a mass of metal elements except lithium in the positive active material, a mass percent of the element M is less than or equal to 0.5%.

10 . The electrochemical device according to claim 6 , wherein 1.0%≤a≤20%.

11 . The electrochemical device according to claim 6 , wherein electrolytic solution comprises an additi

Assignees

• Ningde Amperex Technology Ltd

Inventors

• Xu Chunrui
• Xu Yanyan
• Zheng Jianming
• Tang Chao

Classifications

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M2300/0042

  Four or more solvents · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M10/4235

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title