Composite conductive agent, preparation method thereof, secondary battery, and electrical device

Patent metadata

Field	Value
Publication number	US-12428537-B2
Application number	US-202318531485-A
Country	US
Kind code	B2
Filing date	Dec 6, 2023
Priority date	Nov 1, 2022
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

A composite conductive agent includes an organic polymer, and a hydroxylated carbon nanotube combined with the organic polymer. The organic polymer includes a polymer having a structural formula represented by formula (1),

In the formula (1), m is an integer ranging from 2500 to 20000, and R 1 is a polymer structure including an ester group and a nitrile group.

First claim

What is claimed is:

1. A composite conductive agent, comprising:
an organic polymer, and
a hydroxylated carbon nanotube combined with the organic polymer;
wherein:
the organic polymer comprises a polymer having a structural formula represented by formula (1),

in the formula (1), m is an integer ranging from 2500 to 20000, and R 1 is a polymer structure comprising an ester group and a nitrile group; and
the polymer structure comprises a polymer structure having a structural formula represented by formula (2),

in the formula (2), ** represents a connection site of the polymer structure, p is an integer ranging from 1000 to 5000, q is an integer ranging from 1000 to 15000, f is an integer ranging from 500 to 4000, 2≤n≤200, each R 2 is independently one selected from

 represents a connection site of R 2 , and M + is one selected from Na + , K + , Li + and NH 4 + .

2. The composite conductive agent according to claim 1 , wherein the composite conductive agent satisfies at least one of following conditions:
(1) the hydroxylated carbon nanotube is combined with the organic polymer through an ester group and/or a hydrogen bond; and
(2) at least one hydroxyl group is attached to a surface of the hydroxylated carbon nanotube.

3. The composite conductive agent according to claim 1 , wherein the composite conductive agent satisfies at least one of following conditions:
(1) in the composite conductive agent, a weight percentage content of the organic polymer is 50% to 90%; and
(2) the hydroxylated carbon nanotube comprises a hydroxylated single-walled carbon nanotube and/or a hydroxylated multi-walled carbon nanotube.

4. A method for preparing the composite conductive agent according to claim 1 , comprising:
enabling acrylate and acrylic acid to react with the hydroxylated carbon nanotube to obtain a pre-reacted mixture; and
polymerizing the pre-reacted mixture with acrylonitrile and a polyether polyol monoacrylate to form the organic polymer combined with the hydroxylated carbon nanotube, thereby obtaining the composite conductive agent.

5. The method according to claim 4 , wherein enabling the acrylate and the acrylic acid to react with the hydroxylated carbon nanotube comprises:
contacting the acrylate and the acrylic acid with the hydroxylated carbon nanotube for reaction, under action of a polymerization aid.

6. The method according to claim 5 , wherein the method satisfies at least one of following conditions:
(1) the acrylate comprises at least one of sodium acrylate, potassium acrylate, lithium acrylate, and ammonium acrylate; and
(2) the polymerization aid comprises sodium dodecylsulfonate and/or sodium dodecylsulfate.

7. The method according to claim 5 , wherein contacting the acrylate and the acrylic acid with the hydroxylated carbon nanotube for reaction, under the action of the polymerization aid comprises:
contacting and mixing the polymerization aid, the acrylate, the acrylic acid, with the hydroxylated carbon nanotube in water to form a mixed solution; and
performing a heat treatment on the mixed solution, to subject the acrylate, the acrylic acid, and the hydroxylated carbon nanotube with a prepolymerization reaction.

8. The method according to claim 7 , wherein the method satisfies at least one of following conditions:
(1) in the mixed solution, a weight percentage content of the acrylate is 3% to 25%;
(2) in the mixed solution, a weight percentage content of the acrylic acid is 5% to 40%;
(3) in the mixed solution, a weight percentage content of the hydroxylated carbon nanotube is 1% to 10%;
(4) in the mixed solution, a weight percentage content of the polymerization aid is 2% to 5%; and
(5) a temperature of the heat treatment is 50° C. to 85° C.

9. The method according to claim 4 , wherein polymerizing the pre-reacted mixture with the acrylonitrile and the polyether polyol monoacrylate comprises:
contacting and polymerizing the pre-reacted mixture with the acrylonitrile and the polyether polyol monoacrylate, under action of a polymerization initiator, to form the polymer structure.

10. The method according to claim 9 , wherein the method satisfies at least one of following conditions:
(1) the polyether polyol monoacrylate comprises at least one of a polyethylene glycol acrylate, a polypropylene glycol acrylate, and a polytetrahydrofuran glycol acrylate; and
(2) the polymerization initiator comprises at least one of potassium sulfate, potassium persulfate, and sodium persulfate.

11. The method according to claim 9 , wherein the step of contacting and polymerizing the pre-reacted mixture with the acrylonitrile and the polyether polyol monoacrylate under the action of the polymerization initiator comprises:
contacting and mixing the polymerization initiator, the acrylonitrile, and the polyether polyol monoacrylate in a solution of the pre-reacted mixture to obtain a mixed solution; and
performing a heat treatment on the mixed solution, to subject the acrylonitrile, the polyether polyol monoacrylate, and the pre-reacted mixture with a polymerization reaction.

12. The method according to claim 11 , wherein the method satisfies at least one of the following conditions:
(1) in the mixed solution, a weight percentage content of the polymerization initiator is 1% to 3%;
(2) in the mixed solution, a weight percentage content of the acrylonitrile is 5% to 30%;
(3) in the mixed solution, a weight percentage content of the polyether polyol monoacrylate is 10% to 40%; and
(4) a temperature of the heat treatment is 50° C. to 85° C.

13. The method according to claim 4 , further comprising:
preparing the polyether polyol monoacrylate, comprising contacting acrylic acid with a polyether polyol for esterification reaction, whereby obtaining the polyether polyol monoacrylate.

14. The method according to claim 13 , wherein the method satisfies at least one of following conditions:
(1) the polyether polyol comprises at least one of a polyethylene glycol, a polypropylene glycol, and a polytetrahydrofuran glycol; and
(2) a polymerization degree of the polyether polyol is 2 to 200.

15. The method according to claim 13 , wherein contacting the acrylic acid with the polyether polyol for esterification reaction comprises:
contacting and mixing the acrylic acid and the polyether polyol in water to form a mixed solution; and
performing a heat treatment on the mixed solution to obtain a solution of the polyether polyol monoacrylate.

16. The method according to claim 15 , wherein the method satisfies at least one of following conditions:
(1) a molar ratio of the acrylic acid to the polyether polyol is (5:1) to (1:1); and
(2) a temperature of the heat treatment is 50° C. to 85° C.

17. The method according to claim 15 , further comprising, before performing the heat treatment on the mixed solution:
adding a catalyst and a polymerization inhibitor to the third mixed solution.

18. The method according to claim 17 , wherein the method satisfies at least one of following conditions:
(1) in the mixed solution, a weight percentage content of the catalyst is 3% to 10%; and
(2) in the mixed solution, a weigh

Assignees

• Contemporary Amperex Technology Hong Kong Ltd

Inventors

• Dai Zhipeng
• Ren Miaomiao
• Yang Xianwei
• Lu Yang
• Zhang Xin

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• C08F290/062

  Polyethers · CPC title

• C08K2201/001

  Conductive additives · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M10/0525

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