Composite fiber electrodes and applications of same

Patent metadata

Field	Value
Publication number	US-2021384493-A1
Application number	US-202117341487-A
Country	US
Kind code	A1
Filing date	Jun 8, 2021
Priority date	Jun 8, 2020
Publication date	Dec 9, 2021
Grant date	—

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, comprising:
two or more types of fibers forming a fiber network, comprising at least a first type of fibers and a second type of fibers, wherein the first type of fibers comprises a first polymer and a first type of particles; and the second type of fibers comprises a second polymer and a second type of particles; and wherein the second polymer is same as or different from the first polymer, and the second type of particles are same as or different from the first type of particles.

2 . The composite electrode of claim 1 , wherein each of the first polymer and the second polymer comprises polyacrylic acid (PAA), polyamide-imide (PAI), polyvinylidene fluoride (PVDF), or polyacrylonitrile (PAN), polyethylene oxide (PEO)

3 . The composite electrode of claim 1 , wherein each of the first type of particles and the second type of particles comprises electrochemically active particles, or electrically conductive particles.

4 . The composite electrode of claim 3 , wherein the electrochemically active particles comprise silicon (Si) particles, Si nanoparticles, Si nanowires, Si-carbon particles, titania particles, and/or precious metal or non-precious metal catalysts particles on non-conductive supports including titania or alumina, and wherein the electrically conductive particles comprise carbon particles, graphite particles, carbon black particles, carbon nanotubes, carbon fibers, or a mixture thereof.

5 . The composite electrode of claim 1 , wherein the first type of fibers is formed by electrospinning a first solution containing the first polymer and the first type of particles; and the second type of fibers is formed by electrospinning a second solution containing another the second polymer and the second type of particles.

6 . The composite electrode of claim 5 , wherein the first type of fibers comprises electrospun Si/PAA fibers, and the second type of fibers comprises electrospun C/PAN fibers. The composite electrode of claim 6 , wherein a ratio of the electrospun Si/PAA fibers to the electrospun C/PAN fibers is 70:30 wt. %.

8 . The composite electrode of claim 7 , 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. %.

9 . An electrochemical device, comprising at least one electrode of claim 1 .

10 . A composite electrode, comprising:
at least one type of fibers forming a fiber network; and at least one type of droplets interspersed in the fiber network, wherein said at least one type of fibers comprises a first polymer and a first type of particles; and wherein said at least one type of droplets comprises a second types of particles.

11 . The composite electrode of claim 10 , wherein each of the first type of particles and the second type of particles comprises electrochemically active particles, or electrically conductive particles.

12 . The composite electrode of claim 11 , wherein the electrochemically active particles comprise silicon (Si) particles, Si nanoparticles, Si nanowires, Si-carbon particles, titania particles, and/or precious metal or non-precious metal catalysts particles on non-conductive supports including titania or alumina, and wherein the electrically conductive particles comprise carbon particles, graphite particles, carbon black particles, carbon nanotubes, carbon fibers, or a mixture thereof.

13 . The composite electrode of claim 10 , wherein said at least one type of droplets further comprises a second polymer.

14 . The composite electrode of claim 13 , wherein each of the first polymer and the second polymer comprises polyacrylic acid (PAA), polyamide-imide (PAI), polyvinylidene fluoride (PVDF), or polyacrylonitrile (PAN).

15 . The composite electrode of claim 13 , wherein said at least one type of fibers is formed by electrospinning a first solution containing the first polymer and the first type of particles, and wherein said at least one type of droplets is formed by spraying/electrospraying a second solution the second polymer and the second type of particles.

16 . The composite electrode of claim 10 , wherein said at least one type of fibers comprises electrospun Si/PAA fibers, and said at least one type of droplets comprises sprayed/electrosprayed C/PVDF droplets, or sprayed/electrosprayed C/PAI droplets.

17 . The composite electrode of claim 16 , wherein a Si:PAA ratio of the electrospun Si/PAA fibers is 60:40 wt. %, and a C:PVDF ratio of the C/PVDF sprayed/electrosprayed droplets is 83:17 wt. %

18 . The composite electrode of claim 17 , having 20 wt. % carbon, 45 wt. % silicon, 35 wt. % binder.

19 . An electrochemical device, comprising at least one electrode of claim 10 .

20 . A composite electrode, being a multi-fiber electrode formed by
coating an electrode ink comprising fibers and a solvent on a membrane/separator or on a conductive substrate to form the multi-fiber electrode after solvent removal, wherein the fibers are pre-formed before preparation of the electrode ink via a fiber spinning process; and wherein the fibers comprises one or more polymers, and/or one or more types of particles.

21 . The composite electrode of claim 20 , wherein the electrode ink further comprises the pre-formed fibers and a polymeric binder dispersed in the solvent.

22 . The composite electrode of claim 20 , wherein the electrode ink comprises the pre-formed fibers and micellar droplets (particles) of a water-insoluble polymer dispersed in the solvent, wherein the solvent is a water/alcohol solvent.

23 . The composite electrode of claim 22 , wherein water-insoluble polymer comprises a perfluorosulfonic acid polymer, or a hydrocarbon polymer with negatively or positively charged ion-exchange groups.

24 . The composite electrode of claim 20 , wherein said one or more types of particles comprise catalyst particles or particles of an electrochemically active material, optionally mixed with a polymeric binder.

25 . The composite electrode of claim 20 , wherein said one or more types of particles comprise micellar polymer droplets.

26 . The composite electrode of claim 20 , wherein the fiber spinning process comprises electrospinning, centrifugal spinning, or gas jet fiber spinning.

27 . The composite electrode of claim 20 , wherein said coating the electrode ink is performed by spraying coating, electrospraying, ultrasonic spraying, or slot-die coating.

28 . The composite electrode of claim 20 , wherein the pre-formed fibers in the electrode ink comprise only one type of fibers.

29 . The composite electrode of claim 20 , 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.

30 . The composite electrode of claim 20 , being a layered electrode structure having multiple layers of composite fiber electrodes deposited onto one another.

31 . The composite electrode of claim 20 , being a layered or gradient-composition electrode structure formed by coating multiple different fiber-containing inks onto one another sequentially.

32 . The composite electrode of cl

Assignees

• Univ Vanderbilt

Inventors

• Pintauro Peter N
• Wycisk Ryszard N

Classifications

• Y02E60/50

  Fuel cells · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/926

  on carbon or graphite · CPC title

• H01M4/925

  supported on carriers, e.g. powder carriers · CPC title

• H01M4/921

  Alloys or mixtures with metallic elements · CPC title