Revised fuel cell cycle for in block reforming fuel cells

Patent metadata

Field	Value
Publication number	US-10340534-B2
Application number	US-201615341376-A
Country	US
Kind code	B2
Filing date	Nov 2, 2016
Priority date	Nov 2, 2016
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

A fuel cell system having at least one fuel cell and a cathode loop for recycling a portion of an unused oxidant from the fuel cell for reuse in the same fuel cell is presented. The cathode loop may comprise an oxidant inlet manifold in the fuel cell configured to supply oxidant to the fuel cell, an oxidant exhaust manifold in the fuel cell configured to receive unused oxidant from said fuel cells, and a cathode ejector configured to receive oxidant from an oxidant source and the oxidant exhaust manifold and to supply oxidant to the oxidant inlet manifold, wherein a portion of said unused oxidant is supplied directly to said oxidant inlet manifold from said oxidant exhaust manifold via said cathode ejector.

First claim

I claim:

1. A solid oxide fuel cell system comprising:
a source of unreformed fuel;
a source of oxidant;
a fuel cell stack comprising a plurality of solid oxide fuel cells, each solid oxide fuel cell comprising an anode, a cathode and an electrolyte, said fuel cell stack further comprising:
a fuel supply manifold configured to receive a reformate and unreformed fuel and to supply the reformate and unreformed fuel to said plurality of anodes;
a fuel exhaust manifold configured to exhaust unused fuel from said fuel cell stack;
an oxidant supply manifold configured to receive an oxidant and to supply the oxidant to said plurality of cathodes; and
an oxidant exhaust manifold configured to exhaust the oxidant from said fuel cell stack;

an anode ejector configured to receive unreformed fuel from said source of fuel and to receive a portion of the unused fuel exhausted from said fuel cell stack;
a reformer comprising a plurality of cold-side channels and a plurality of hot-side channels, said reformer further comprising:
a fuel supply manifold configured to receive fuel from said anode ejector and to supply the fuel to said plurality of cold-side channels;
a fuel exhaust manifold configured to exhaust reformate from said plurality of cold-side channels and to supply the reformate to said fuel supply manifold of said fuel cell stack;
an oxidant inlet manifold configured to receive a portion of the oxidant exhausted from said fuel cell stack and to supply the oxidant to said plurality of hot-side channels; and
an oxidant exhaust manifold configured to exhaust the oxidant from said plurality of hot-side channels;

an auxiliary ejector configured to receive a portion of the unused fuel exhausted from said fuel cell stack and to receive the oxidant exhausted from said plurality of hot channels;
a combustor configured to receive unused fuel and oxidant exhausted from the auxiliary ejector;
a turbine configured to receive the exhaust from the combustor;
a compressor configured to receive oxidant from said oxidant source; and
a cathode ejector configured to receive oxidant from said compressor and to receive oxidant exhausted from said oxidant exhaust manifold of said fuel cell stack and to supply oxidant to said oxidant inlet manifold of said fuel cell stack.

2. The solid oxide fuel cell system of claim 1 further comprising a bypass duct configured to receive fuel exhausted from said anode ejector and to supply the fuel to the reformate exhausted from said cold-side channels upstream of said fuel supply manifold of said fuel cell stack.

3. The solid oxide fuel cell system of claim 2 wherein at least 10% of said fuel exhausted by said anode ejector passes through said bypass duct.

4. The solid oxide fuel cell system of claim 2 wherein between 10% and 90% of said fuel exhausted from said anode ejector passes through said bypass duct.

5. The solid oxide fuel cell system of claim 1 wherein the oxidant exhausted from said cathode ejector is supplied to said oxidant inlet manifold of said fuel cell stack without passing through a heat exchanger.

6. The solid oxide fuel cell system of claim 1 further comprising a heat exchanger comprising a plurality of cold-side channels and a plurality of hot-side channels, said heat exchanger being configured to receive oxidant from said cathode ejector in said cold-side channels and being configured to receive exhaust from said combustor in said hot-side channels.

7. The solid oxide fuel cell system of claim 1 further comprising a heat exchanger comprising a plurality of cold-side channels and a plurality of hot-side channels, said heat exchanger being configured to receive oxidant from said compressor in said cold-side channels and being configured to receive exhaust from said combustor in said hot-side channels.

8. The solid oxide fuel cell system of claim 1 wherein no more than 33% of the oxidant exhausted from said oxidant exhaust manifold of said fuel cell stack passes through said hot-side channels of said reformer.

9. The solid oxide fuel cell system of claim 1 wherein between 10% and 33% of the oxidant exhausted from said oxidant exhaust manifold of said fuel cell stack passes through said hot-side channels of said reformer.

10. The solid oxide fuel cell system of claim 1 further comprising a heat exchanger comprising a plurality of cold-side channels and a plurality of hot-side channels, said heat exchanger being configured to receive oxidant from said compressor in said cold-side channels and being configured to receive exhaust from said turbine in said hot-side channels.

11. A solid oxide fuel cell system comprising:
a solid oxide fuel cell stack comprising at least one solid oxide fuel cell, each solid oxide fuel cell comprising an anode, a cathode, and an electrolyte;
a reformer comprising cold-side channels and hot-side channels;
an anode loop for supplying fuel and reformate to the anode of each solid oxide fuel cell, said anode loop comprising:
a fuel inlet manifold in said fuel cell stack configured to supply fuel and reformate to the anode of each solid oxide fuel cell;
a fuel exhaust manifold configured to receive unused fuel from the anode of each solid oxide fuel cell;
a source of fuel;
an anode ejector configured to receive fuel from said fuel source and said fuel exhaust manifold;
the cold-side channels of said reformer configured to receive fuel from said anode ejector;

a cathode loop for supplying oxidant to the cathode of each solid oxide fuel cell, said cathode loop comprising:
an oxidant inlet manifold in said fuel cell stack configured to supply oxidant to the cathode of each solid oxide fuel cell;
an oxidant exhaust manifold in said fuel cell stack configured to receive unused oxidant from each cathode of said solid oxide fuel cells;
a source of oxidant;
a cathode ejector configured to receive oxidant from said oxidant source and said oxidant exhaust manifold and configured to supply oxidant to said oxidant inlet manifold; and

an auxiliary loop for combusting a portion of the unused fuel from said fuel exhaust manifold and a portion of the unused oxidant from said oxidant exhaust manifold, said auxiliary loop comprising:
the hot-side channels of said reformer configured to receive a portion of the unused oxidant from said oxidant exhaust manifold;
an auxiliary ejector configured to receive the oxidant from the hot-side channels of said reformer, a portion of the oxidant from said oxidant source, and a portion of the unused fuel from said fuel exhaust manifold; and
a combustor configured to receive the exhaust from said auxiliary ejector.

12. The solid oxide fuel cell system of claim 11 further comprising a compressor configured to receive oxidant from said oxidant source.

13. The solid oxide fuel cell system of claim 11 further comprising a turbine configured to receive the exhaust from said combustor.

14. The solid oxide fuel cell system of claim 13 further comprising a heat exchanger having hot-side channels and cold-side channels, wherein said cold-side channels of said heat exchanger are disposed in said cathode loop and are configured to receive oxidant from said oxidant source and to supply oxidant to said cathode ejector, and wherein said hot-side channels of said heat exchanger are configured to receive an exhaust from said turbine.

15. The solid oxide fuel cell system of claim 11 further comprising a heat exchanger having hot-side channels and cold-side channels, wherein said cold-side channels of said heat exchanger are disposed in said cathode loop and are configured to receive oxidant from said oxidant

Assignees

• Lg Fuel Cell Systems Inc

Inventors

• Bozzolo Michele

Classifications

• H01M8/0267

  having heating or cooling means, e.g. heaters or coolant flow channels · CPC title

• H01M8/0662

  Treatment of gaseous reactants or gaseous residues, e.g. cleaning · CPC title

• Y02E60/525

  Cross-Sectional Technologies · mapped topic

• H01M8/24

  Grouping of fuel cells, e.g. stacking of fuel cells · CPC title

• H01M8/04097 Primary

  with recycling of the reactants (H01M8/04119, H01M8/04104 take precedence) · CPC title