Metal-air fuel cell battery system employing substantially planar metal-fuel cards of rigid construction insertable into a power generation bay of the system

• US 6,309,771 B1
• Filed: 08/31/1998
• Issued: 10/30/2001
• Est. Priority Date: 10/06/1997
• Status: Expired due to Fees

• Current Assignee: Reveo, Inc.
• Original Assignee: Reveo, Inc.
• Inventors: Faris, Sadeg M., Yao, Wayne, Chang, Yuen-Ming, Tsai, Tsepin
• Primary Examiner(s): Kalafut, Stephen
• Application Number:
  US09/143,895
• Time in Patent Office: 1,156 Days
• Field of Search: 429/25, 429/27, 429/68, 429/90, 429/127, 429/208, 429/233
• US Class Current: 429/404
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 50/72 Constructional details of fuel cells specially adapted for electric vehicles
• CPC Class Codes: B60L 58/33 by cooling
• CPC Class Codes: H01M 10/4214 Arrangements for moving electrodes or electrolyte
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 12/06 with one metallic and one gaseous electrode
• CPC Class Codes: H01M 12/08 composed of a half-cell of a fuel-cell type and a half-cell of the secondary-cell type
• CPC Class Codes: H01M 2004/024 Insertable electrodes
• CPC Class Codes: H01M 2300/0085 Immobilising or gelification of electrolyte
• CPC Class Codes: H01M 4/42 Alloys based on zinc
• CPC Class Codes: H01M 4/8605 Porous electrodes
• CPC Class Codes: H01M 50/46 Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: H01M 6/5011 for several cells simultaneously or successively
• CPC Class Codes: H01M 8/184 Regeneration by electrochemical means
• CPC Class Codes: H01M 8/186 by electrolytic decomposition of the electrolytic solution or the formed water product
• CPC Class Codes: H01M 8/22 Fuel cells in which the fuel is based on materials comprising carbon or oxygen or hydrogen and other elements; Fuel cells in which the fuel is based on materials comprising only elements other than carbon, oxygen or hydrogen
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

Improved metal-air fuel cell battery systems having metal-fuel realized in the form of substantially planar metal-fuel cards of rigid construction, which can be either manually or automatically inserted within the power generation bay of the system. The power generation bay includes at least one electrically-conductive cathode element supported by a cathode support structure in a stationary position with respect to the cathode support structure, and at least one electrically-conductive anode-contacting element supported by an anode contacting structure in a stationary position with respect to the anode contacting structure. In order to produce a range of output voltages, the power generation bay includes a plurality of cells comprising cathode elements spatially arranged with anode contacting elements, and each metal-fuel card has a plurality of electrically-isolated metal-fuel strips that are spatially arranged with these cells when the metal-fuel card is inserted to the power generation bay. An output voltage configuration subsystem is provided for configuring the voltages produced by the individual cells to produce a desired output. A subsystem is provided for detecting oxide formation on the metal-fuel strips so that only metal-fuel that has been oxidized is reduced during recharging operations. A subsystem is also provided for controlling the flow of oxygen into the power generation head in order to control the power output from the system.

Claims

1. A metal-air fuel cell battery (FCB) system for producing and supplying electrical power to an electrical load, the system comprising:

first and second output power supply terminals for electrically coupling to an electrical load;

at least one electrically-conductive cathode element pervious to oxygen and supported by a cathode support structure in a stationary position with respect to the cathode support structure;

at least one electrically-conductive anode-contacting element supported by an anode-contacting structure in a stationary position with respect to the anode-contacting structure;

a substantially planar anode structure of rigid construction comprising the at least one metal-fuel element, functioning as an electrically-conductive anode element when removably disposed between the at least one cathode element and the at least one anode-contacting element, and wherein the at least one electrically-conductive anode-contacting element establishes electrical contact with the at least one metal-fuel element when the substantially planar anode structure is removably disposed between the at least one cathode element and the at least one anode-contacting element;

an ionically-conductive medium disposed between said at least one cathode element and said at least one metal-fuel element;

a first electrically-conductive pathway from said at least one electrically-conductive cathode element to said first output power supply terminal; and

a second electrically-conductive pathway from said at least one electrically-conductive anode-contacting element to said second output power supply terminal;

wherein electrical power is produced across said at least one electrically-conductive cathode element and said at least one electrically-conductive anode element for delivery to the electrical load.

2. The metal-air fuel cell battery system of claim 1, wherein said cathode support structure has a recess for supporting said at least one electrically-conductive cathode element.

3. The metal-air fuel cell battery system of claim 2, wherein said ionically-conductive medium comprises an electrolyte-impregnated pad disposed over said at least one electrically-conductive cathode element within said recess.

4. The metal-air fuel cell battery system of claim 1, wherein said at least one cathode element comprises an electrically-conductive mesh substrate to which said first electrically-conductive pathway is electrically connected, and porous carbon material adhered to said electrically-conductive mesh substrate.

5. The metal-air fuel cell battery system of claim 4, wherein said electrically-conductive mesh substrate is made of nickel, and said electrically-conductive anode element is made of zinc.

6. The metal-air fuel cell battery system of claim 4, wherein said electrically-conductive cathode element further comprises a catalyst material embodied the within said porous carbon material.

7. The metal-air fuel cell battery system of claim 1, wherein said cathode support structure comprises:

a cathode support plate having a recess for supporting said at least one electrically-conductive cathode element, and

a plurality of air holes formed in a surface of said recess to permit ambient air to flow through said at least one electrically-conductive cathode element.

8. The metal-air fuel cell battery system of claim 7, which further comprises:

air-throttling means associated with said cathode support structure, for throttling the flow of ambient air through said plurality of air holes.

9. The metal-air fuel cell battery system of claim 1, which further comprises:

means for sensing the partial oxygen pressure (PO2) within said at least one electrically-conductive cathode element, and producing an electrical signal indicative thereof.

10. The metal-air fuel cell battery system of claim 1, which further comprises

means for sensing the electrical current flowing into the electrical load, and

means for sensing the electrical voltage across the electrical load.

11. The metal-air fuel cell battery system of claim 8, which further comprises a system controller for controlling said air-throttling means.

12. The metal-air fuel cell battery system of claim 11, wherein said system controller comprises a microcontroller.

13. The metal-air fuel cell battery system of claim 1, which further comprises:

means for transporting said at least one metal-fuel element relative to said at least one electrically-conductive cathode element.

14. The metal-air fuel cell battery system of claim 13, which further comprises:

means for transporting said substantially planar anode structure in response to a predetermined condition.

15. The metal-air fuel cell battery system of claim 1, which further comprises output voltage configuration means for configuring the output voltage at the power output terminals;

and wherein

said cathode support structure supports a plurality of electrically-conductive cathode elements in a stationary position with respect to the cathode support structure;

said anode-contacting structure supports a plurality of electrically-conductive anode-contacting elements in a stationary position with respect to the anode-contacting structure;

wherein said plurality of electrically-conductive cathode elements are spatially registered with respect to said plurality of anode-contacting elements;

said substantially planar anode structure comprises a plurality of metal-fuel elements, functioning as electrically-conductive anode elements spatially registered with respect to the plurality of cathode elements and anode-contacting elements when the substantially planar anode structure is removably disposed between the plurality of cathode elements and the plurality of anode-contacting elements, and wherein the plurality of anode-contacting elements establish electrical contact with the plurality of metal-fuel elements when the substantially planar anode structure is removably disposed between the plurality of cathode elements and the plurality of anode-contacting elements;

said first electrically-conductive pathway comprising a first plurality of electrical conductors, each being connected from one said electrically-conductive cathode element to said output voltage configuration means; and

said second electrically-conductive pathway comprising a second plurality of electrical conductors each being connected from one electrically-conductive anode contacting element to said output voltage configuration means;

wherein said output voltage configuration means selectively configured the voltages across said first and second plurality of electrical conductors so as to produce a selected output voltage across said first and second output power supply terminals.

16. The metal-air fuel cell battery system of claim 15, which further comprises means for sensing an electrical condition associated with said electrical load connected to said first and second output power supply terminals.

17. The metal-air fuel cell battery system of claim 15, which further comprises means for sensing oxide formation on each said metal fuel element supported within said metal fuel support structure.

18. The metal-air fuel cell battery system of claim 17, which further comprises reduction means for reducing each said metal fuel element on which oxide formation has been sensed.

19. The metal-air fuel cell battery system of claim 18 which further comprises power supply means for providing electrical power to said reduction means.

20. The metal-air fuel cell battery system of claim 6, wherein said catalyst material comprises platinum embodied within said porous carbon material.