Composite fiber electrodes and applications of same

Patent metadata

Field	Value
Publication number	US-12266787-B2
Application number	US-202117341487-A
Country	US
Kind code	B2
Filing date	Jun 8, 2021
Priority date	Jun 8, 2020
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

A composite electrode includes two or more types of fibers forming a fiber network, comprising at least a first type of fibers and a second type of fibers. The first type of fibers comprises a first polymer and a first type of particles. The second type of fibers comprises a second polymer and a second type of particles. The second polymer is same as or different from the first polymer. The second type of particles are same as or different from the first type of particles.

First claim

What is claimed is:

1. A composite electrode, being a multi-fiber electrode, comprising:
a membrane/separator or an electrically conductive substrate; and
a fiber network coated on the membrane/separator or the electrically conductive substrate with an electrode ink comprising pre-formed fibers and a solvent,
wherein the pre-formed fibers are pre-formed before preparation of the electrode ink via a fiber spinning process;
wherein the pre-formed fibers comprise one or more polymers, and one or more particles;
wherein said one or more particles comprise catalyst particles or particles of an electrochemically active material; and
wherein the electrochemically active particles comprise silicon (Si) particles, Si nanoparticles, Si nanowires, Si-carbon particles, Si oxide particles, titania particles, and/or precious metal or non-precious metal catalysts particles on conductive or non-conductive supports, wherein the non conductive supports include titania or alumina, and wherein the conductive supports include carbon particles, graphite particles, carbon black particles, carbon nanotubes, carbon fibers, or a mixture thereof.

2. The composite electrode of claim 1 , wherein the electrode ink further comprises a polymeric binder dispersed in the solvent.

3. The composite electrode of claim 1 , wherein the electrode ink further comprises micellar droplets (particles) of a water-insoluble polymer dispersed in the solvent, wherein the solvent is a water/alcohol solvent.

4. The composite electrode of claim 3 , wherein water-insoluble polymer comprises a perfluorosulfonic acid polymer, or a hydrocarbon polymer with negatively or positively charged ion-exchange groups.

5. The composite electrode of claim 1 , wherein said one or more particles further comprise micellar polymer droplets.

6. The composite electrode of claim 1 , wherein the fiber spinning process comprises electrospinning, centrifugal spinning, or gas jet fiber spinning.

7. The composite electrode of claim 1 , wherein the electrode ink is coated on the membrane/separator or the electrically conductive substrate by spray coating, electrospraying, ultrasonic spraying, slot-die coating, gravure coating, doctor-blade coating, or spin coating.

8. The composite electrode of claim 1 , wherein the pre-formed fibers in the electrode ink comprise only one fiber.

9. The composite electrode of claim 1 , wherein the pre-formed fibers in the electrode ink comprise two or more different types of fibers, wherein each type of the fibers differs in the type/amount of particles, and/or the type/amount of a polymer binder, and/or the fiber morphology including fiber diameter and internal fiber porosity.

10. The composite electrode of claim 1 , being a layered electrode structure having multiple layers of composite fiber electrodes deposited onto one another.

11. The composite electrode of claim 1 , being a layered or gradient-composition electrode structure formed by coating multiple different fiber-containing inks onto one another sequentially.

12. The composite electrode of claim 11 , wherein each of said multiple different fiber-containing inks differs in fiber type/structure including fiber diameter and porosity, fiber composition, and binder type and amount.

13. The composite electrode of claim 11 , wherein thickness and porosity of each layer are fixed or variable.

14. The composite electrode of claim 1 , wherein the pre-formed fibers in the electrode ink comprise electrospun Si/PAA fibers.

15. The composite electrode of claim 14 , wherein a Si: PAA ratio of the electrospun Si/PAA fibers is 60:40 wt. %.

16. The composite electrode of claim 15 , having 20 wt. % carbon, 45 wt. % silicon, 35 wt. % binder.

17. The composite electrode of claim 1 , wherein the pre-formed fibers in the electrode ink comprise electrospun Si/PAA fibers, and electrospun C/PAN fibers.

18. The composite electrode of claim 17 , wherein a ratio of the electrospun Si/PAA fibers to the electrospun C/PAN fibers is 70:30 wt. %.

19. The composite electrode of claim 18 , wherein a Si:PPA ratio of the electrospun Si/PAA fibers is 50:50 wt. %, and a C:PAN ratio of the electrospun C/PAN fibers is 63:37 wt. %.

20. The composite electrode of claim 1 , wherein the one or more polymers comprise polyacrylic acid (PAA), polyamide-imide (PAI), polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), and/or polyethylene oxide (PEO).

21. An electrochemical device, comprising at least the composite electrode of claim 1 .

Assignees

• Univ Vanderbilt

Inventors

• Pintauro Peter N
• Wycisk Ryszard N

Classifications

• D06M11/74

  with carbon or graphite; with carbides; with graphitic acids or their salts · CPC title

• D10B2321/10

  polymers of unsaturated nitriles, e.g. polyacrylonitrile, polyvinylidene cyanide · CPC title

• D10B2401/10

  porous · CPC title

• D06M2101/28

  Acrylonitrile; Methacrylonitrile · CPC title

• H01M2004/021

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