A/C—D/C power system with internal fuel cell

• US 7,119,458 B2
• Filed: 08/19/2003
• Issued: 10/10/2006
• Est. Priority Date: 10/01/2002
• Status: Expired due to Fees

• Current Assignee: MTI MicroFuel Cells, Inc. (Soluna Holdings, Inc.)
• Original Assignee: MTI MicroFuel Cells, Inc. (Soluna Holdings, Inc.)
• Inventors: Bunch, James T. Jr., Barnes, Judith A.
• Primary Examiner(s): Feild, Lynn
• Assistant Examiner(s): RUTLAND WALLIS, MICHAEL
• Application Number:
  US10/643,442
• Publication Number:
  US 20050040785A1
• Time in Patent Office: 1,148 Days
• Field of Search: 307/65, 307/43, 307/66, 320/111, 320/101
• US Class Current: 307/65
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H02J 2207/40 adapted for charging from various sources, e.g. AC, DC or multivoltage
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: H02J 9/061 for DC powered loads
• CPC Class Codes: Y02B 90/10 Applications of fuel cells in buildings
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

An A/C-D/C-F/C power system is provided that includes a portable power unit that can accept electricity from a number of alternative sources including an AC power source, a DC power source, a battery, and a direct oxidation fuel cell. In accordance with one embodiment of the invention, the fuel cell is used to either recharge a battery, or to power an application device, when the AC source and/or the DC source are unavailable. The A/C-D/C-F/C system of the present invention also includes signal processing and signal conditioning circuitry in a power combiner and conditioner, which condition the voltage signal to deliver power to the application device in a manner that is consistent with device requirements.

Claims

1.

A method for charging and maintaining the operation of a battery-powered electronic application device, including the steps of:

(A) providing a controllable switching device;

(B) providing a plurality of power sources each coupled to said application device via said controllable switching device, said plurality of power sources including at least two of the following;

(i) an AC power source;

(ii) a DC power source;

(iii) a direct oxidation fuel cell; and

(iv) a rechargeable battery; and

(C) switching said controllable switching device to select between said plurality of power sources to provide operating power to said application device or to charge said rechargeable battery;

(D) selecting as a primary power source, said AC power source and determining whether said AC power source is available;

(E) if said AC power source is available, selecting said AC power source to power said application device; and

(F) if said AC power source is not available, determining whether said DC power source is available and if so, selecting said DC power source to power said application device;

(G) if said DC power source is not available, determining whether said rechargeable battery is sufficiently charged to power said application device and if so, selecting said rechargeable battery to power said application device; and

(H) if said rechargeable battery is not sufficiently charged, responsively signaling said direct oxidation fuel cell to begin generating electricity to provide current to power said application device.

2. A system for powering an electronic application device, comprising:

(A) an input adaptable to receive power from an AC power source;

(B) an input adaptable to receive power from a DC power source;

(C) a direct oxidation fuel cell system;

(D) a means by which said system may be electrically connected to said electronic application device;

(E) a switching device connected to said AC input, said DC input and said fuel cell wherein said switching device is operable to select between a first state in which current flows through said switching device from said AC input, a second state in which current flows from said DC input and a third state in which current is drawn from said fuel cell system; and

(F) a microprocessor coupled to said switching device and programmed to select between said AC power source, said DC power source and said fuel cell system, depending upon predetermined conditions; and

a rechargeable battery connected to said input from said DC source, said input from AC power source and with said fuel cell system, and said microprocessor being programmed to select the rechargeable battery to power the application device if said DC source and said AC source are not available,;

wherein said microprocessor is further programmed to signal one of said DC power source, AC power source and fuel cell system to deliver power to charge said rechargeable battery while the application device is connected to one of the other non-selected sources so that the battery will be charged as the application device is being powered.

3. The system as defined in claim 2, further comprising a power combiner and conditioner which is adapted to perform signal processing and signal conditioning to the power source selected by said microprocessor such that the power signal is compatible with the specifications of the application device.

4. The system as defined in claim 2, wherein said direct oxidation fuel cell system includes

(A) a fuel source;

(B) a housing;

(C) a direct oxidation fuel cell comprising a protonically conductive, electronically non-conductive membrane electrolyte having an anode aspect and a cathode aspect, and a catalyst coating being disposed on the anode and the cathode aspects such that when fuel is introduced to the anode aspect an anodic disassociation of the fuel into carbon dioxide protons and electrons occurs and a cathodic combination of protons, electrons and oxygen produces water whereby current is produced from the electricity generating reactions to provide current to a load associated with the fuel cell system.

5. The system as defined in claim 4, further comprising a modular interface having a smart cable that includes a set of pins for providing a desired voltage for said application device.