Fabrication of membrane electrode assembly with filament extension atomizer spray

Patent metadata

Field	Value
Publication number	US-11909052-B2
Application number	US-202117364163-A
Country	US
Kind code	B2
Filing date	Jun 30, 2021
Priority date	Jun 30, 2021
Publication date	Feb 20, 2024
Grant date	Feb 20, 2024

Abstract

A method and apparatus are described for forming a multilayer assembly. The method includes adhering first and second catalyst layers to opposed sides of a polymer membrane. At least one of the first catalyst layer, the second catalyst layer, and the polymer membrane is formed by filament extension atomization of a fluid material to form atomized droplets that are sprayed to form the respective membrane or layer.

First claim

What is claimed is:

1. A method for forming a multilayer assembly comprising:
providing a first catalyst layer in contact with a first side of a polymer membrane, the first catalyst layer being formed from a first layer-forming material comprising a polymer and catalyst particles, dispersed in the polymer, the first layer-forming material further comprising at least one solvent, wherein a total solvent is no more than 10 wt. % of the first layer-forming material;
providing a second catalyst layer in contact with an opposed second side of the polymer membrane, the second catalyst layer being formed from the first layer-forming material or from a second layer-forming material comprising a polymer and catalyst particles, dispersed in the polymer;
wherein at least one of the first catalyst layer, the second catalyst layer, and the polymer membrane is formed by filament extension atomization of a fluid material to form atomized droplets that are sprayed to form the respective membrane or layer.

2. The method of claim 1 , wherein the total solvent is no more than 5 wt. % of the first layer-forming material.

3. The method of claim 1 , wherein the first layer-forming material is sprayed onto one of the membrane and a microporous layer.

4. The method of claim 1 , wherein the first catalyst layer comprises at least two sub-layers of a controllable thickness, a first of the sublayers having a higher concentration of the catalyst particles than a second of the sublayers.

5. The method of claim 1 , further comprising varying a concentration of catalyst particles in the first catalyst layer in a direction parallel to a thickness of the membrane.

6. The method of claim 1 , further comprising varying a concentration of catalyst particles in the first catalyst layer in a direction perpendicular to a thickness of the membrane.

7. A method for forming a multilayer assembly comprising:
providing a first catalyst layer in contact with a first side of a polymer membrane, the first catalyst layer being formed from a first layer-forming material comprising a polymer and catalyst particles, dispersed in the polymer;
providing a second catalyst layer in contact with an opposed second side of the polymer membrane, the second catalyst layer being formed from the first layer-forming material or from a second layer-forming material comprising a polymer and catalyst particles, dispersed in the polymer;
wherein the polymer membrane is formed by filament extension atomization of a membrane-forming material to form atomized droplets that are sprayed on at least one of the first and second catalyst layers, the membrane-forming material comprising a molten thermoset polymer.

8. The method of claim 1 , wherein an interface between the first catalyst layer and the membrane is non-planar.

9. The method of claim 1 , further comprising adhering the first catalyst layer to a first microporous layer and adhering the second catalyst layer to a second microporous layer.

10. The method of claim 9 , further comprising coating the first microporous layer with a fluoropolymer layer formed by filament extension atomization of a fluid fluoropolymer material prior to adhering the first catalyst layer to a first microporous layer.

11. The method of claim 1 , wherein the polymer membrane is proton-permeable.

12. The method of claim 1 , further comprising incorporating the multilayer assembly into a membrane electrode assembly, the membrane electrode assembly comprising first and second electrodes spaced by the multilayer assembly.

13. The method of claim 1 , wherein:
the filament extension atomization of the first catalyst layer forming material is performed with a first filament extension atomizer which generates an aerosol from the first catalyst layer forming material in fluid form, by stretching the fluid material in a nip defined between rotating rollers; and
forming the first catalyst layer with a first applying station which receives the aerosol, the first applying station including outlets which deposit droplets of the aerosol on a substrate to form the first catalyst layer, the substrate comprising one of a microporous layer and the polymer membrane;
the first applying station, or a second applying station, applying the other of the microporous layer and the polymer membrane to the first catalyst layer.

14. The method of claim 1 , wherein:
the polymer and catalyst particles comprise at least 20 wt. % of the first catalyst layer material;
the method further comprising:
adhering a first microporous layer to the first catalyst layer; and
curing the first catalyst layer material.

15. A method for forming a multilayer assembly the multilayer comprising first and second microporous layers, a polymer membrane, a first catalyst layer in contact with a first side of the polymer membrane and a second catalyst layer in contact with a second side of the polymer membrane, the method comprising:
spraying atomized droplets formed by filament extension atomization of a first layer-forming material to form a first catalyst layer on one of the first microporous layer and the first side of the polymer membrane, the first layer-forming material comprising a polymer and catalyst particles, dispersed in the polymer, the first layer-forming material comprising no more than 10 wt. % of solvent; and
spraying atomized droplets formed by filament extension atomization of a second layer-forming material to form the second catalyst layer on one of the second microporous layer and the second side of a polymer membrane, the second layer-forming material comprising a polymer and catalyst particles, dispersed in the polymer, the second layer-forming material comprising no more than 10 wt. % of solvent.

Assignees

• Palo Alto Res Ct Inc
• Xerox Corp

Inventors

• Karatay Elif
• Murphy Kathryn F

Classifications

• B05B3/04

  driven by the liquid or other fluent material discharged, e.g. the liquid actuating a motor before passing to the outlet · CPC title

• H01M4/8825 Primary

  Methods for deposition of the catalytic active composition · CPC title

• B05B3/0409

  Operations & Transport · mapped topic

• H01M4/8642

  Gradient in composition · CPC title

• H01M4/881 Primary

  Electrolytic membranes · CPC title