Reforming catalyst pattern for fuel cell operated with enhanced CO2 utilization

Patent metadata

Field	Value
Publication number	US-12095129-B2
Application number	US-202318110097-A
Country	US
Kind code	B2
Filing date	Feb 15, 2023
Priority date	Nov 30, 2018
Publication date	Sep 17, 2024
Grant date	Sep 17, 2024

Abstract

A reforming element for a molten carbonate fuel cell stack and corresponding methods are provided that can reduce or minimize temperature differences within the fuel cell stack when operating the fuel cell stack with enhanced CO2 utilization. The reforming element can include at least one surface with a reforming catalyst deposited on the surface. A difference between the minimum and maximum reforming catalyst density and/or activity on a first portion of the at least one surface can be 20% to 75%, with the highest catalyst densities and/or activities being in proximity to the side of the fuel cell stack corresponding to at least one of the anode inlet and the cathode inlet.

First claim

The invention claimed is:

1. A fuel cell stack comprising:
a molten carbonate fuel cell comprising an anode and a cathode;
a reforming element associated with the anode, the reforming element comprising a first surface, the first surface comprising a first portion comprising a reforming catalyst, a reforming catalyst density on the first portion of the first surface comprising a monotonically decreasing catalyst density, the reforming catalyst density on the first portion of the first surface having a difference between a maximum catalyst density and a minimum catalyst density of 20% to 75%, wherein the difference is calculated by subtracting the minimum catalyst density from the maximum catalyst density and then dividing by the maximum catalyst density; and
a separator plate between the anode and the reforming element.

2. The fuel cell stack of claim 1 , wherein the maximum catalyst density is in proximity to an anode inlet, or wherein the maximum catalyst density is in proximity to a cathode inlet.

3. The fuel cell stack of claim 1 , wherein the minimum catalyst density is in proximity to an anode outlet, or wherein the minimum catalyst density is in proximity to a cathode outlet.

4. The fuel cell stack of claim 1 , wherein the first surface further comprises a second portion, the second portion being in proximity to a cathode inlet or in proximity to an anode inlet, the second portion comprising a constant catalyst density.

5. The fuel cell stack of claim 1 , wherein the reforming catalyst comprises parallel lines of catalyst particles.

6. The fuel cell stack of claim 1 , wherein the difference between a maximum catalyst density and a minimum catalyst density is 20% to 40%.

7. The fuel cell stack of claim 1 , wherein the first surface comprises an interior surface of the anode.

8. A fuel cell stack comprising:
a molten carbonate fuel cell comprising an anode and a cathode;
a reforming element comprising a first surface, the first surface comprising a reforming catalyst, a reforming catalyst density on the first surface comprising a monotonically decreasing catalyst density, the reforming catalyst density on the first surface having a difference between a maximum catalyst density and a minimum catalyst density of 20% to 75%, wherein the difference is calculated by subtracting the minimum catalyst density from the maximum catalyst density and then dividing by the maximum catalyst density; and
a separator plate between the anode and the reforming element.

9. The fuel cell stack of claim 8 , wherein the maximum catalyst density is in proximity to an anode inlet, or wherein the maximum catalyst density is in proximity to a cathode inlet.

10. The fuel cell stack of claim 8 , wherein the minimum catalyst density is in proximity to an anode outlet or wherein the minimum catalyst density is in proximity to a cathode outlet.

11. The fuel cell stack of claim 8 , wherein the difference between a maximum catalyst density and a minimum catalyst density is 20% to 50%.

12. The fuel cell stack of claim 8 , wherein the first surface comprises an interior surface of the reforming element.

13. A fuel cell stack comprising:
a molten carbonate fuel cell comprising an anode and a cathode; and
the anode comprising a first surface, the first surface comprising a reforming catalyst, a reforming catalyst density on the first surface comprising a monotonically decreasing catalyst density, the reforming catalyst density on the first surface having a difference between a maximum catalyst density and a minimum catalyst density of 20% to 75%, wherein the difference is calculated by subtracting the minimum catalyst density from the maximum catalyst density and then dividing by the maximum catalyst density.

14. The fuel cell stack of claim 13 , wherein the maximum catalyst density is in proximity to an anode inlet or wherein the maximum catalyst density is in proximity to a cathode inlet.

15. The fuel cell stack of claim 13 , wherein the minimum catalyst density is in proximity to an anode outlet or wherein the minimum catalyst density is in proximity to a cathode outlet.

16. The fuel cell stack of claim 13 , wherein the reforming catalyst comprises parallel lines of catalyst particles.

17. The fuel cell stack of claim 13 , wherein the first surface comprises an interior surface of the anode.

18. The fuel cell stack of claim 8 , wherein the difference between a maximum catalyst density and a minimum catalyst density is 20% to 40%.

Assignees

• Exxonmobil Technology & Engineering Company
• Fuelcell Energy Inc

Inventors

• O'Neal Everett J
• Han Lu
• Pereira Carla S
• Blanco Gutierrez Rodrigo F
• Healy Timothy M
• Willman Carl A
• Ghezel-Ayagh Hossein
• Dobek Jr Frank J

Classifications

• H01M4/861

  with a gradient in the porosity · CPC title

• H01M8/04753

  of fuel cell reactants · CPC title

• H01M8/04388

  of anode reactants at the inlet or inside the fuel cell · CPC title

• H01M8/04395

  of cathode reactants at the inlet or inside the fuel cell · CPC title

• H01M8/0631

  Reactor construction specially adapted for combination reactor/fuel cell (hydrogen C01B3/00; reactors for physicochemical processes B01J19/00) · CPC title