SYSTEMS AND METHODS FOR PROTECTING A FUEL CELL

• US 20080171239A1
• Filed: 07/30/2007
• Published: 07/17/2008
• Est. Priority Date: 02/02/2005
• Status: Abandoned Application

• Current Assignee: UltraCell Corporation (Bren-Tronics, Inc.)
• Original Assignee: UltraCell Corporation (Bren-Tronics, Inc.)
• Inventors: Allen, Joseph Norman, Richardson, Robert D., Kaye, Ian W., Tucker, Gerry
• Application Number:
  US11/830,665
• Publication Number:
  US 20080171239A1
• Time in Patent Office: Days
• US Class Current: 429/13
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 2008/1095 Fuel cells with polymeric electrolytes
• CPC Class Codes: H01M 2250/30 Fuel cells in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 8/0258 characterised by the configuration of channels, e.g. by the flow field of the reactant or coolant
• CPC Class Codes: H01M 8/04007 related to heat exchange
• CPC Class Codes: H01M 8/04067 Heat exchange or temperature measuring elements, thermal insulation, e.g. heat pipes, heat pumps, fins
• CPC Class Codes: H01M 8/04186 of liquid-charged or electrolyte-charged reactants
• CPC Class Codes: H01M 8/04197 Preventing means for fuel crossover
• CPC Class Codes: H01M 8/04225 during start-up
• CPC Class Codes: H01M 8/043 applied during specific periods
• CPC Class Codes: H01M 8/04302 applied during start-up
• CPC Class Codes: H01M 8/04365 of other components of a fuel cell or fuel cell stacks
• CPC Class Codes: H01M 8/04388 of anode reactants at the inlet or inside the fuel cell
• CPC Class Codes: H01M 8/04559 of fuel cell stacks
• CPC Class Codes: H01M 8/04589 of fuel cell stacks
• CPC Class Codes: H01M 8/04679 of fuel cell stacks
• CPC Class Codes: H01M 8/04753 of fuel cell reactants
• CPC Class Codes: H01M 8/0491 of fuel cell stacks
• CPC Class Codes: H01M 8/04917 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/0494 of fuel cell stacks
• CPC Class Codes: H01M 8/04947 : of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04955 : Shut-off or shut-down of fuel cells
• CPC Class Codes: H01M 8/0612 : from carbon-containing material
• CPC Class Codes: H01M 8/0618 : Reforming processes, e.g. autothermal, partial oxidation or steam reforming
• CPC Class Codes: H01M 8/1011 : Direct alcohol fuel cells [DAFC], e.g. direct methanol fuel cells [DMFC]
• CPC Class Codes: H01M 8/241 : with solid or matrix-supported electrolytes
• CPC Class Codes: H01M 8/2457 : with both reactants being gaseous or vaporised
• 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

The invention relates to hybrid fuel cell systems that protect a fuel cell with a second electrical energy source. The second electrical energy source powers a load to prevent the fuel cell from witnessing stoichiometric levels that may lead to reductions in fuel cell performance or health. The hybrid fuel cell system includes an electrical circuit that electrically initiates the electrical energy source to provide power to the load in response to detecting a potential stoichiometric disturbance for the fuel cell.

Claims

1. A method of operating a portable electrical power source, the method comprising:

generating electrical energy in a fuel cell;

providing the fuel cell electrical energy to a load;

detecting a potential stoichiometric disturbance for the fuel cell;

in response to detecting the potential stoichiometric disturbance, electrically initiating a secondary electrical energy source to provide electrical energy to the load;

recording a flow rate of oxygen and a flow rate of hydrogen to the fuel cell;

in response to detecting the potential stoichiometric disturbance, electrically disconnecting the fuel cell from the load;

maintaining oxygen flow and hydrogen flow to the fuel cell while the secondary electrical energy source provides electrical energy to the load and while the fuel cell is electrically disconnected from the load; and

altering the flow rate of oxygen or the flow rate of hydrogen according to an electrical state of the load.