Battery electrode binder material

Patent metadata

Field	Value
Publication number	US-12388089-B2
Application number	US-202318462577-A
Country	US
Kind code	B2
Filing date	Sep 7, 2023
Priority date	Sep 28, 2022
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

Methods of preparing a dry powder blend co-coagulating conductive carbon black particles and fibrillizable polytetrafluoroethylene particles from an aqueous dispersion and drying the co-coagulate are described. Dry powders prepared by such methods and electrodes prepared from such powders are also described.

First claim

What is claimed is:

1. A method of preparing a powder comprising
forming a mixture by combining conductive carbon black particles having a D50 particle size of 10 to 150 nanometers with an aqueous latex comprising fibrillizable polytetrafluoroethylene particles having a D50 particle size of 40 to 200 nanometers, wherein a size ratio of the D50 particle size of the fibrillizable polytetrafluoroethylene particles to the D50 particle size of the carbon black particles is from 1.1:1 to 5:1, inclusive;
co-coagulating the conductive carbon black particles and the fibrillizable polytetrafluoroethylene particles to form a co-coagulate; and
drying the co-coagulate to form a powder blend comprising at least 90 wt. % of the conductive carbon black particles and the fibrillizable polytetrafluoroethylene particles, based on the total weight of the powder blend, wherein the powder blend comprises 15 to 45 wt. % of the conductive carbon black particles and 55 to 85 wt. % of the fibrillizable polytetrafluoroethylene particles.

2. The method of claim 1 , further comprising homogenizing the mixture prior to co-coagulating the conductive carbon black particles and the fibrillizable polytetrafluoroethylene particles.

3. The method of claim 1 , wherein a ratio of weight of the fibrillizable polytetrafluoroethylene particles to weight of the conductive carbon black particles in the powder is from 2:1 to 4:1.

4. The method of claim 3 , wherein the aqueous latex has a pH of 4 to 6 and a surface tension of 15 to 30 mN/m.

5. The method of claim 1 , wherein the conductive carbon black particles have a D50 particle size of 20 to 60 nanometers.

6. The method of claim 5 , wherein the fibrillizable polytetrafluoroethylene particles have a D50 particle size of 60 to 90 nanometers.

7. The method of claim 1 , wherein the mixture is formed by combining an aqueous dispersion of the conductive carbon black particles with the aqueous latex comprising the fibrillizable polytetrafluoroethylene particles.

8. A powder made the method of claim 1 .

9. A powder comprising at least 90 wt. % of a co-coagulated blend of conductive carbon black particles having a D50 particle size of 10 to 150 nanometers and fibrillizable polytetrafluoroethylene particles having a D50 particle size of 40 to 200 nanometers, wherein a ratio of weight of the fibrillizable polytetrafluoroethylene particles to weight of the conductive carbon black particles in the powder is from 1.1:1 to 5:1, inclusive.

10. The powder of claim 9 , comprising 20 to 40 wt. % of the conductive carbon black particles and 60 to 80 wt. % of the fibrillizable polytetrafluoroethylene particles.

11. The powder of claim 9 , wherein the conductive carbon black particles have a D50 particle size of 20 to 60 nanometers and the fibrillizable polytetrafluoroethylene particles have a D50 particle size of 60 to 90 nanometers.

12. The powder of claim 9 , wherein a size ratio of the D50 particle size of the fibrillizable polytetrafluoroethylene particles to the D50 particle size of the carbon black particles is from 2:1 to 4:1, inclusive.

13. A powder of claim 9 further comprising a thermally conductive filler, optionally wherein the thermally conductive filler is selected from the group consisting of boron nitride, aluminum oxide, and combinations thereof.

14. A method of preparing an electrode comprising spreading the powder of claim 9 on a support and fibrillating the fibrillizable polytetrafluoroethylene particles.

15. An electrode prepared by the method of claim 14 .

Assignees

• 3M Innovative Properties Company

Inventors

• Mitchell Michael H
• Dadalas Michael C
• Muggli Mark W
• Traunspurger Helmut
• STREITER André
• Eberman Kevin W
• Bartling Brandon A

Classifications

• H01M4/623 Primary

  fluorinated polymers · CPC title

• H01M4/625 Primary

  Carbon or graphite · CPC title