Electrode layer composition, process for the manufacture thereof and membrane electrode assembly

Patent metadata

Field	Value
Publication number	US-12580202-B2
Application number	US-202418422103-A
Country	US
Kind code	B2
Filing date	Jan 25, 2024
Priority date	Jan 25, 2023
Publication date	Mar 17, 2026
Grant date	Mar 17, 2026

Abstract

There is provided a process for the manufacture of an electrode layer composition for electrochemical devices, such as for fuel cells. Also provided is an electrode layer composition, such as a composition obtainable by the disclosed process. The electrode layer composition comprises electrode liquid carrier, catalyst and ion exchange material, wherein at least a portion of the ion exchange material is bound to the catalyst and the weight ratio of ion exchange material bound to the catalyst compared to the total amount of ion exchange material in the composition is at least 0.3. A method for the determination of the bound ratio of an electrode layer composition is also disclosed.

First claim

The invention claimed is:

1 . A process for the manufacture of an electrode layer composition for a membrane electrode assembly, said process comprising:
providing a catalyst composition comprising an ion exchange material, a catalyst, and a catalyst liquid carrier; removing the catalyst liquid carrier to produce a catalyst-ionomer cake comprising the ion exchange material and the catalyst; heating the catalyst-ionomer cake at a temperature of at least 100° C., wherein at least a portion of the ion exchange material is bound to the catalyst; providing an electrode liquid carrier; and dispersing the catalyst-ionomer cake in the electrode liquid carrier to produce an electrode layer composition comprising the catalyst, the ion exchange material, and the electrode liquid carrier in which at least a portion of the ion exchange material is bound to the catalyst, wherein the electrode layer composition has a bound ratio; wherein the bound ratio is a weight ratio of the ion exchange material bound to the catalyst compared to a total amount of the ion exchange material in the electrode layer composition; and wherein the bound ratio is at least 0.3.

2 . The process as claimed in claim 1 , wherein the providing the catalyst composition comprises:
providing the catalyst, the catalyst liquid carrier, and the ion exchange material; and combining the catalyst, the catalyst liquid carrier, and the ion exchange material to produce the catalyst composition comprising:
combining the catalyst and the catalyst liquid carrier;
homogenizing the catalyst and the catalyst liquid carrier to produce a catalyst dispersion comprising the catalyst and the catalyst liquid carrier; and
combining the catalyst dispersion with the ion exchange material to produce the catalyst composition.

3 . The process as claimed in claim 2 , wherein the combining the catalyst dispersion with the ion exchange material further comprises homogenizing the catalyst dispersion combined with the ion exchange material to produce the catalyst composition.

4 . The process as claimed in claim 1 , wherein the removing the catalyst liquid carrier comprises drying the catalyst composition.

5 . The process as claimed in claim 1 , wherein the dispersing the catalyst-ionomer cake in the electrode liquid carrier comprises combining the catalyst-ionomer cake and the electrode liquid carrier; wherein the combining the catalyst-ionomer cake and the electrode liquid carrier further comprises homogenizing the catalyst-ionomer cake and the electrode liquid carrier to produce the electrode layer composition.

6 . The process as claimed in claim 1 , wherein the catalyst liquid carrier comprises water and one or more C 1 -C 4 alcohols selected from the group consisting of ethanol, 1-propanol, 2-propanol, and combinations thereof; wherein a concentration of the one or more C 1 -C 4 alcohols in the catalyst liquid carrier is less than 75% by weight.

7 . The process as claimed in claim 1 , wherein the providing the electrode liquid carrier further comprises providing a further ion exchange material; wherein the dispersing the catalyst-ionomer cake in the electrode liquid carrier further comprises combining the catalyst-ionomer cake with the further ion exchange material such that the electrode layer composition comprises the catalyst, the ion exchange material, the further ion exchange material and the electrode liquid carrier, in which at least a portion of the ion exchange material is bound to the catalyst; wherein the further ion exchange material is not bound to the catalyst.

8 . The process as claimed in claim 1 , wherein the providing the electrode liquid carrier further comprises providing a further catalyst; wherein the dispersing the catalyst-ionomer cake in the electrode liquid carrier further comprises combining the catalyst-ionomer cake with the further catalyst such that the electrode layer composition comprises the catalyst, the further catalyst, the ion exchange material and the electrode liquid carrier, in which at least a portion of the ion exchange material is bound to the catalyst; wherein the ion exchange material is not bound to the further catalyst.

9 . The process as claimed in claim 1 , wherein the providing the electrode liquid carrier further comprises providing a further liquid carrier; wherein the dispersing the catalyst-ionomer cake in the electrode liquid carrier further comprises combining the catalyst-ionomer cake with the further liquid carrier such that the electrode layer composition comprises the catalyst, the ion exchange material, the electrode liquid carrier and the further liquid carrier, in which at least a portion of the ion exchange material is bound to the catalyst.

10 . The process as claimed in claim 1 , wherein the catalyst comprises a catalytic component and a catalyst support; wherein the catalyst support is a carbon particulate; wherein the catalytic component comprises one or more of Pt, Ir, Ni, Co, Pd, Ti, Sn, Ta, Nb, Sb, Pb, Mn, Ru and Fe, their oxides, and mixtures thereof; wherein a ratio of the ion exchange material to the catalyst support in the catalyst composition is less than or equal to 1.40.

11 . The process as claimed in claim 1 , wherein the ion exchange material comprises at least one ionomer comprising a proton conducting polymer; wherein the proton conducting polymer comprises perfluorosulfonic acid.

12 . An electrode layer composition obtained by the process of claim 1 ;
wherein at least a portion of the ion exchange material is bound to the catalyst; wherein a weight ratio of the ion exchange material bound to the catalyst compared to a total weight of the ion exchange material in the electrode layer composition is at least 0.3.

13 . A process for manufacturing a membrane electrode assembly component, said process comprising:
providing a first electrode layer composition obtained by the process of claim 1 , said first electrode layer composition comprising a first catalyst, a first ion exchange material and a first electrode liquid carrier, in which at least a portion of the first ion exchange material is bound to the first catalyst; applying the first electrode layer composition to a first side of an electrolyte membrane to provide a layer of the first electrode layer composition on the first side of the electrolyte membrane; and heating the layer of the first electrode layer composition on the first side of the electrolyte membrane to remove the electrode liquid carrier from the first electrode layer composition to provide a first electrode on the electrolyte membrane, wherein the first electrode comprises the first catalyst and the first ion exchange material to produce the membrane electrode assembly component comprising the first electrode and the electrolyte membrane.

14 . A process for manufacturing a membrane electrode assembly comprising the process of claim 13 , and further comprising:
providing a second electrode layer composition obtained by the process of claim 1 , said second electrode layer composition comprising a second catalyst, a second ion exchange material and a second electrode liquid carrier, in which at least a portion of the second ion exchange material is bound to the second catalyst; applying the second electrode layer composition to a second side of the electrolyte membrane, the second side opposite to that of the first side of the electrolyte membrane, to provide a layer of the second electrode layer composition on the second side of the electrolyte membrane; and heating the layer of the second electrode layer composition on the second side of the electrolyte membrane to remove th

Assignees

• Gore & Ass
• W L Gore & Ass G K

Inventors

• Edmundson Mark D
• Maruyama Masashi
• Sakamoto Atsushi
• Tani Masaki

Classifications

• H01M4/926

  on carbon or graphite · CPC title

• H01M4/9041

  Metals or alloys (H01M4/92 takes precedence) · CPC title

• H01M4/8882

  Heat treatment, e.g. drying, baking · CPC title

• H01M8/1004

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

• Y02E60/50

  Fuel cells · CPC title