Nanofiber membrane-electrode-assembly and method of fabricating same

Patent metadata

Field	Value
Publication number	US-9876246-B2
Application number	US-201514964220-A
Country	US
Kind code	B2
Filing date	Dec 9, 2015
Priority date	Oct 27, 2010
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

In one aspect of the present invention, a method of fabricating a fuel cell membrane-electrode-assembly (MEA) having an anode electrode, a cathode electrode, and a membrane disposed between the anode electrode and the cathode electrode, includes fabricating each of the anode electrode, the cathode electrode, and the membrane separately by electrospinning; and placing the membrane between the anode electrode and the cathode electrode, and pressing then together to form the fuel cell MEA.

First claim

What is claimed is:

1. A method of fabricating a fuel cell membrane-electrode-assembly (MEA) having an anode electrode, a cathode electrode, and a membrane disposed between the anode electrode and the cathode electrode, comprising:
fabricating each of the anode electrode, the cathode electrode, and the membrane separately by electrospinning; and
placing the membrane between the anode electrode and the cathode electrode, and pressing them together to form the fuel cell MEA,
wherein the step of fabricating the membrane comprises:
forming one or more first-type polymer solutions from one or more first-type polymers and one or more second-type polymer solutions from one or more second-type polymers, respectively, wherein each of the one or more first-type polymers comprises a charged polymer and each of the one or more second-type polymers comprises a uncharged (or minimally charged) polymer;
electrospinning, separately and simultaneously, the one or more first-type polymer solutions and the one or more second-type polymer solutions to form a dual or multi fiber mat of one or more first-type polymer fibers and one or more second-type polymer fibers; and
processing the dual or multi fiber mat by softening and flowing at least one of the one or more first-type polymer fibers to fill in the void space between the one or more second-types polymer fibers, or by softening and flowing at least one of the one or more second-type polymer fibers to fill in the void space between the one or more first-types polymer fibers, so as to form the membrane.

2. The method of claim 1 , wherein the one or more first-type polymer fibers comprise ionically conducting polymer fibers, and the one or more second-type polymer fibers comprise uncharged (or minimally charged) polymer fibers.

3. The method of claim 2 , wherein the uncharged (or minimally charged) polymer is polyphenylsulfone, and the ionically conducting polymer is a perfluorosulfonic acid polymer.

4. The method of claim 1 , wherein the step of processing the dual or multi fiber mat by softening and flowing at least one of the one or more first-type polymer fibers comprises:
compressing the dual or multi fiber mat; and
thermal annealing the dual or multi fiber mat to soften and flow at least one of the one or more first-type polymer fibers to fill in the void space between the one or more second-type polymer fibers.

5. The method of claim 1 , wherein the step of processing the dual or multi fiber mat by softening and flowing at least one of the one or more second-type polymer fibers comprises:
compressing the dual or multi fiber mat; and
exposing the dual or multi fiber mat to solvent vapor to soften and flow at least one of the one or more second-type polymer fibers to fill in the void space between the one or more first-type polymer fibers.

6. The method of claim 5 , wherein the step of processing the dual or multi fiber mat by softening and flowing the at least one of the one or more second-type polymer fibers further comprises:
thermal annealing the dual or multi fiber mat.

7. The method of claim 1 , wherein the step of fabricating each of the anode electrode and the cathode electrode comprises:
forming a polymer solution containing a catalyst and an ionomer or an uncharged (or minimally charged) polymer;
electrospinning the polymer solution to generate electrospun fibers so as to form a nanofiber mat; and
pressing the nanofiber mat to fabricate the electrode.

8. The method of claim 7 , wherein the catalyst comprises platinum-supported carbon (Pt/C).

9. The method of claim 7 , wherein the ionomer or uncharged polymer comprises Nafion®.

10. A method of fabricating a fuel cell membrane-electrode-assembly (MEA), comprising:
fabricating a first nanofiber electrode by electrospinning;
sequentially fabricating a nanofiber membrane on the first nanofiber electrode by electrospinning; and
sequentially fabricating a second nanofiber electrode on the nanofiber membrane by electrospinning to form the fuel cell MEA,
wherein one of the first and second nanofiber electrodes is an anode electrode, and the other of the first and second nanofiber electrodes is a cathode electrode,
wherein the step of fabricating the nanofiber membrane comprises:
forming one or more first-type polymer solutions from one or more first-type polymers and one or more second-type polymer solutions from one or more second-type polymers, respectively, wherein each of the one or more first-type polymers comprises a charged polymer and each of the one or more second-type polymers comprises a uncharged (or minimally charged) polymer;
electrospinning, separately and simultaneously, the one or more first-type polymer solutions and the one or more second-type polymer solutions to form a dual or multi fiber mat of one or more first-type polymer fibers and one or more second-type polymer fibers; and
processing the dual or multi fiber mat by softening and flowing at least one of the one or more first-type polymer fibers to fill in the void space between the one or more second-types polymer fibers, or by softening and flowing at least one of the one or more second-type polymer fibers to fill in the void space between the one or more first-types polymer fibers, so as to form the membrane.

Assignees

• Univ Vanderbilt

Inventors

• Pintauro Peter N
• Ballengee Jason
• Brodt Matthew

Classifications

• H01M8/1004 Primary

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• H01G11/52

  Separators · CPC title

• H01M8/1007

  with both reactants being gaseous or vaporised (H01M8/12 takes precedence) · CPC title

• B32B2262/0238

  Vinyl halide, e.g. PVC, PVDC, PVF, PVDF · CPC title

• B29C48/142

  using force fields, e.g. gravity or electrical fields (B29C48/9165 takes precedence) · CPC title