Fuel cell and power chip technology

• US 6,312,846 B1
• Filed: 11/24/1999
• Issued: 11/06/2001
• Est. Priority Date: 11/24/1999
• Status: Expired due to Term

• Current Assignee: Encite, LLC
• Original Assignee: Integrated Fuel Cell Technologies Incorporated (Encite, LLC)
• Inventors: Marsh, Stephen A.
• Primary Examiner(s): Brouillette, Gabrielle
• Assistant Examiner(s): WILLS, MONIQUE M
• Application Number:
  US09/449,377
• Time in Patent Office: 713 Days
• Field of Search: 429/12, 429/30, 429/34, 429/35, 429/36, 429/38, 429/39, 429/41
• US Class Current: 429/430
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 8/0271 Sealing or supporting means around electrodes, matrices or membranes
• CPC Class Codes: H01M 8/0432 Temperature; Ambient temperature
• CPC Class Codes: H01M 8/04365 of other components of a fuel cell or fuel cell stacks
• CPC Class Codes: H01M 8/0438 Pressure; Ambient pressure; Flow
• CPC Class Codes: H01M 8/04552 of the individual fuel cell
• CPC Class Codes: H01M 8/04582 of the individual fuel cell
• CPC Class Codes: H01M 8/04619 of fuel cell stacks
• CPC Class Codes: H01M 8/04753 of fuel cell reactants
• CPC Class Codes: H01M 8/0488 of fuel cell stacks
• CPC Class Codes: H01M 8/0491 of fuel cell stacks
• CPC Class Codes: H01M 8/0494 of fuel cell stacks
• CPC Class Codes: H01M 8/1097 Fuel cells applied on a support, e.g. miniature fuel cells deposited on silica supports
• CPC Class Codes: H01M 8/1286 Fuel cells applied on a support, e.g. miniature fuel cells deposited on silica supports
• CPC Class Codes: H01M 8/241 with solid or matrix-supported electrolytes
• CPC Class Codes: H01M 8/2418 Grouping by arranging unit cells in a plane H01M8/2425, H01M8/244 take precedence
• CPC Class Codes: H01M 8/2457 with both reactants being gaseous or vaporised
• CPC Class Codes: H01M 8/249 comprising two or more groupings of fuel cells, e.g. modular assemblies
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y10T 29/49108 : Electric battery cell making
• CPC Class Codes: Y10T 29/53135 : Storage cell or battery

Abstract

A fuel cell is disclosed which is formed on a semiconductor wafer by etching channel in the wafer and forming a proton exchange membrane PEM barrier in the etched channel. The barrier divides the channel into two. A hydrogen fuel is admitted into one of the divided channels and an oxidant into the other.

The hydrogen reacts with a catalyst formed on an anode electrode at the hydrogen side of the channel to release hydrogen ions (protons) which are absorbed into the PEM. The protons migrate through the PEM and recombine with return hydrogen electrons on a cathode electrode on the oxygen side of the PEM and the oxygen to form water.

Claims

1. An array of fuel cells comprising:

(a) a substrate having;

(i) a plurality of first and second channels formed in the substrate for admitting hydrogen into the first channel and oxygen into the second channel;

(ii) membranes having first and second sides formed on the substrate and separating the first channels from the second channels;

(iii) a first electrode on the first side of each of the membranes and a second electrode on the second side of each of the membranes;

(iv) a catalyst in contact with said membrane sides and the electrodes; and

(b) a gas impermeable cover enclosing said array.

8. The array of claim 1 wherein a plurality of the cells are electrically coupled together on the wafer to form a power chip and an oxygen port and a hydrogen port is coupled to the respective channels in each chip.

9. The array of claim 8 wherein the substrate is formed of semiconductor material.

10. The array of claim 9 wherein the semiconductor is taken from the group comprising Si, Ge, or GaAs.

11. The array of claim 8 wherein the power chip includes a microcontroller integrated onto the wafer for monitoring and controlling a power output from the chip.

12. The array of claim 11 wherein the microcontroller provides dynamic active area control to optimize hydrogen consumption efficiency thermal efficiency and ion-exchange efficiency.

13. The array of claim 12 in which transister switches are formed on the chip which are under the control of the microcontroller.

14. The array of claim 11 wherein the power output is programmable.

2. A fuel cell comprising:

(i) first and second channels formed in a substrate for admitting hydrogen into the first channel and oxygen into the second channel;

(ii) a membrane having first and second sides formed on the substrate and separating the first channel from the second channel;

(iii) a first electrode on the first side of the membrane and a second electrode on the second side of the membrane;

(iv) a catalyst in electrical communication with the membrane sides and the electrodes; and

(v) a gas impermeable cover enclosing the cell.

4. The fuel cell of claim 2 wherein the catalyst is incorporated in the first and second membrane sides.

5. The fuel cell of claim 2 in which a microcontroller is integrated onto the substrate in electrical communication with the fuel cell.

6. The fuel cell of claim 2 in which the membrane is formed of a polymer.

7. The cell of claim 6 in which the membrane is a proton exchange membrane.

3. An array of fuel cells formed on a wafer comprising:

(a) a planar semiconductor substrate having;

(i) a plurality of first and second channels formed in the substrate for admitting hydrogen into the first channel and oxygen into the second channel;

(ii) a plurality of membranes having first and second sides formed on the substrate and separating the first channel from the second channel;

(iii) a first electrode on the first side of each membrane and a second electrode on the second side of each membrane;

(iv) a catalyst in electrical communication with the first and second membrane sides; and

(b) a gas impermeable cover enclosing said array and wherein said cells are electrically interconnected to form a power chip and wherein a group of power chips comprise a power disc and wherein said power discs are stacked vertically.

15. A method of forming a scalable array of fuel cells on a wafer comprising the steps of:

(a) forming a plurality of first and second channels in a substrate for admitting hydrogen into the first channel and oxygen into the second channel;

(b) forming membranes having first and second sides between the channels to separate the first channel from the second channel;

(c) forming a catalyst in electrical communication with the first and second sides of the membranes;

(d) forming a first electrode on the first side of each membrane and a second electrode on the second side of each membrane in electrical communication with the catalyst; and

(e) enclosing said array with a gas impermeable cover.

17. The method of claim 15 wherein the catalyst is formed of platinum.

18. The method of claim 15 wherein portions of the array are electrically interconnected to form a power cell.

19. The method of claim 18 wherein channels in the power cells are coupled to a hydrogen fuel and other channels to a source of oxygen.

16. A method of forming a fuel cell comprising the steps of:

(a) forming first and second channels in a substrate for admitting hydrogen from a first port into the first channel and oxygen from a second port into the second channel;

(b) forming a membrane having first and second sides on the substrate to separate the first channel from the second channel;

(c) forming a catalyst in electrical communication with the first and second channels and the first sides of the membrane;

(d) forming a first electrode on the first side of the membrane and a second electrode on the second electrode on the second side of the membrane; and

(e) providing a gas impermeable cover enclosing the cell.

20. A fuel cell comprising:

(i) a channel formed in a substrate;

(ii) a membrane having first and second sides formed on the substrate and separating the channel into two separate flow paths;

(iii) a first electrode on the first side of the membrane and a second electrode on the second side of the membrane;

(iv) a catalyst in electrical communication with the membrane sides and the electrodes; and

(v) a gas impermeable cover enclosing the cell.

21. The cell of claim 20 in which a port for introducing hydrogen is coupled to one of the two paths and a port for introducing oxygen is coupled into another path.

22. A method of forming a fuel cell comprising the steps of:

(a) forming three flow channels, an inner channel and two outer channels, in a substrate wherein each outer channel is separated from the inner channel by a wall having a plurality of vertical slits;

(b) forming an electrode on a base of an outer side of each wall;

(c) forming a catalyst plurality of tines formed between the slits, and wherein said catalyst contacts said electrodes.