Positive electrode composition and production method for same, positive electrode and production method for same, and battery

Patent metadata

Field	Value
Publication number	US-2025219087-A1
Application number	US-202318848068-A
Country	US
Kind code	A1
Filing date	Jan 17, 2023
Priority date	Mar 30, 2022
Publication date	Jul 3, 2025
Grant date	—

Abstract

A positive electrode composition containing a conductive material, an active material, a binding material, a dispersing agent for a conductive material, and a liquid medium, wherein the conductive material includes carbon black and carbon nanotubes, wherein the dispersing agent for a conductive material includes two or more dispersing agents having different SP values, and wherein the carbon black has a BET specific surface area of 100 to 500 m 2 /g.

First claim

1 . A positive electrode composition containing a conductive material, an active material, a binding material, a dispersing agent for a conductive material, and a liquid medium,
wherein the conductive material includes carbon black and carbon nanotubes, wherein the dispersing agent for a conductive material includes two or more dispersing agents having different SP values, and wherein the carbon black has a BET specific surface area of 100 to 500 m 2 /g.

2 . The positive electrode composition according to claim 1 ,
wherein a ratio (mass ratio) of the content of the carbon nanotubes to a total content of the carbon black and the carbon nanotubes is 0.1 to 0.7.

3 . The positive electrode composition according to claim 1 ,
wherein the dispersing agent for a conductive material is selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl butyral, carboxymethyl cellulose and salts thereof, polyvinyl acetal, polyvinyl acetate, polyvinylamine and polyvinyl formal.

4 . The positive electrode composition according to claim 1 ,
wherein the carbon black has a BET specific surface area of 100 to 400 m 2 /g and a crystallite size (Lc) of 15 to 26 Å.

5 . The positive electrode composition according to claim 1 ,
wherein the carbon nanotubes have an average diameter of 5 to 15 nm.

6 . A method of producing the positive electrode composition according to claim 1 , comprising:
a first process in which a first agent containing a binding material and a first liquid medium, a second agent containing carbon black, a first dispersing agent for a conductive material and a second liquid medium, and a third agent containing carbon nanotubes, a second dispersing agent for a conductive material and a third liquid medium are mixed to obtain a mixed solution; and a second process in which the mixed solution and an active material are mixed to obtain a positive electrode composition, wherein the first dispersing agent for a conductive material has a different SP value from the second dispersing agent for a conductive material.

7 . A method of producing the positive electrode composition according to claim 1 , comprising:
a first process in which a first agent containing a binding material and a first liquid medium and a second agent containing carbon black, a first dispersing agent for a conductive material and a second liquid medium are mixed to obtain a first mixed solution; a second process in which the first mixed solution and a third agent containing carbon nanotubes, a second dispersing agent for a conductive material and a third liquid medium are mixed to obtain a second mixed solution; and a third process in which the second mixed solution and an active material are mixed to obtain a positive electrode composition, wherein the first dispersing agent for a conductive material has a different SP value from the second dispersing agent for a conductive material.

8 . The production method according to claim 6 ,
wherein the SP value of the first dispersing agent for a conductive material is higher than the SP value of the second dispersing agent for a conductive material.

9 . The production method according to claim 6 ,
wherein a ratio (mass ratio) of the content of the carbon nanotubes to a total content of the carbon black and the carbon nanotubes is 0.1 to 0.7.

10 . The production method according to claim 6 ,
wherein the first dispersing agent for a conductive material and the second dispersing agent for a conductive material each are selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl butyral, carboxymethyl cellulose and salts thereof, polyvinyl acetal, polyvinyl acetate, polyvinylamine and polyvinyl formal.

11 . A method of producing a positive electrode, comprising
a process of applying the positive electrode composition according to claim 1 onto a current collector to form a mixture layer containing the conductive material, the active material, the binding material and the dispersing agent for a conductive material on the current collector.

12 . A positive electrode having a mixture layer containing a conductive material, an active material, a binding material and a dispersing agent for a conductive material,
wherein the conductive material includes carbon black and carbon nanotubes, wherein the dispersing agent for a conductive material includes two or more dispersing agents having different SP values, and wherein the carbon black has a BET specific surface area of 100 to 500 m 2 /g.

13 . The positive electrode according to claim 12 ,
wherein a ratio (mass ratio) of the content of the carbon nanotubes to a total content of the carbon black and the carbon nanotubes is 0.1 to 0.7.

14 . The positive electrode according to claim 12 ,
wherein the dispersing agent for a conductive material is selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl butyral, carboxymethyl cellulose and salts thereof, polyvinyl acetal, polyvinyl acetate, polyvinylamine and polyvinyl formal.

15 . A battery comprising the positive electrode according to claim 12 .

16 . The production method according to claim 7 ,
wherein the SP value of the first dispersing agent for a conductive material is higher than the SP value of the second dispersing agent for a conductive material.

17 . The production method according to claim 7 ,
wherein a ratio (mass ratio) of the content of the carbon nanotubes to a total content of the carbon black and the carbon nanotubes is 0.1 to 0.7.

18 . The production method according to claim 7 ,
wherein the first dispersing agent for a conductive material and the second dispersing agent for a conductive material each are selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl butyral, carboxymethyl cellulose and salts thereof, polyvinyl acetal, polyvinyl acetate, polyvinylamine and polyvinyl formal.

Assignees

• Denka Company Ltd

Inventors

• Nagai Tatsuya
• Matsui Mizuki
• Ito Tetsuya

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/021

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

• H01M10/0525

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

• H01M4/1391

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