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A method and apparatus for the operation of a fuel cell system to avoid the freezing of water resident in one or more fuel cells during periods of system inactivity. Each fuel cell includes at least an anode, a cathode and a membrane configured to establish electrolyte communication between reaction

A method and apparatus for the operation of a fuel cell system to avoid the freezing of water resident in one or more fuel cells during periods of system inactivity. Each fuel cell includes at least an anode, a cathode and a membrane configured to establish electrolyte communication between reaction products formed at the anode and cathode. During fuel cell system operation, a portion of the water formed remains within the fuel cell; to avoid having the water freeze and inhibit subsequent system operation, a chemical compound introduced into the fuel cells mixes with the water still resident within the fuel cell to lower the temperature upon which the onset of water freezing occurs. The chemical compound can be introduced alone under pressure in the vapour phase, or in combination with the fuel, the incoming oxygen or an inert gas. In addition, system is configured such that the chemical compound can be introduced at numerous different locations.

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1. A method of operating a fuel cell system, said method comprising:configuring at least one fuel cell within said system to include an anode, a cathode and a membrane disposed between said anode and said cathode; defining an operational sequence of said system to include a period of system activity

1. A method of operating a fuel cell system, said method comprising:configuring at least one fuel cell within said system to include an anode, a cathode and a membrane disposed between said anode and said cathode; defining an operational sequence of said system to include a period of system activity wherein fuel is reacted with oxygen to produce electricity and at least one reaction product; arranging an infeed device to selectively introduce a chemical compound that upon mixing with said at least one reaction product lowers the freezing temperature of said at least one reaction product; configuring a data storage device to record at least one of a temperature inside said fuel cell and an ambient temperature over a repeated time interval such that said at least one of said ambient temperature and said temperature inside said fuel cell sensed over said repeated time interval defines a historical value database; sensing at least one temperature indicative of the temperature of said at least one fuel cell; analyzing said historical value database to determine whether said sensed temperature indicates the attainment of a fuel cell temperature below that of a predetermined threshold temperature; generating a temperature-based control signal as a first control signal when said sensed temperature is below that of said predetermined threshold temperature; and activating said infeed device upon generation of said temperature-based control signal. 2. A method according to claim 1, wherein said at least one temperature indicative of the temperature of said at least one fuel cell is an ambient temperature.3. A method according to claim 1, wherein said at least one temperature indicative of the temperature of said at least one fuel cell is a temperature inside said fuel cell.4. A method according to claim 1, wherein prior to said step of activating said infeed device, said method comprises the additional step of generating a second control signal that together with said first control signal is configured to activate said infeed device.5. A method according to claim 4, wherein said step of generating said second control signal is in response to switching off said system such that substantially no electricity is produced.6. A method according to claim 4, wherein said step of generating said second control signal is in response to a user-defined override.7. A method according to claim 4, wherein said step of generating said second control signal is in response to a predetermined time of day.8. A method according to claim 1, wherein said fuel cell system includes a fuel cell stack comprising a plurality of fuel cells.9. A method according to claim 1, wherein said infeed device is operated during a shutdown period and where said chemical compound substantially displaces the substantial entirety of at least one of said fuel and oxygen that was present in said fuel cell just prior to said shutdown period.10. A method according to claim 1, comprising the additional step of storing said chemical compound in a supply tank prior to selectively introducing said chemical compound.11. A method according to claim 10, wherein said supply tank is sized to hold up to approximately ten quarts of said chemical compound when said chemical compound is in liquid form.12. A method according to claim 10, wherein said supply tank is sized to hold up to approximately one quart of said chemical compound when said chemical compound is in liquid form.13. A method according to claim 1, wherein said chemical compound is in a vapor phase when introduced to said at least one fuel cell.14. A method according to claim 1, wherein said chemical compound is in a liquid phase when introduced to said at least one fuel cell.15. A method according to claim 1, comprising the additional step of pressurizing said chemical compound prior to introducing said chemical compound to said at least one fuel cell.16. A method according to claim 1, wherein said chemical compound is introduced in an anode flowpath, said anode flowpath configured to establish fluid coupling between said anode and a fuel supply.17. A method according to claim 16, wherein said chemical compound is mixed with said fuel in said anode flowpath.18. A method according to claim 1, wherein said chemical compound is introduced in a cathode flowpath, said cathode flowpath configured to establish fluid coupling between said cathode and an oxygen supply.19. A method according to claim 18, wherein said chemical compound is mixed with said oxygen in said cathode flowpath.20. A method according to claim 1, further comprising an inert gas supply device in selective fluid communication with at least one of said anode or said cathode such that an inert gas can be introduced into said fuel cell system simultaneously with said chemical compound.21. A method according to claim 20, wherein said chemical compound is mixed with said inert gas upstream of said anode.22. A method according to claim 1, wherein said chemical compound is liquid at the normal freezing temperature of said at least one reaction product, but gaseous at a temperature corresponding to said fuel cell system activity.23. A method according to claim 1, wherein said chemical compound is miscible with water.24. A method according to claim 23, wherein said chemical compound has a boiling point in the range between approximately 68° F. and approximately 176° F.25. A method according to claim 24, wherein said chemical compound has a freezing point below approximately ?40° F.26. A method according to claim 1, wherein said chemical compound is selected from the group consisting of alcohols, bases, acids, sugars with at least one functional group and 1 to 20 carbon atoms, and compounds including hydrogen and at least one of carbon and nitrogen.27. A method according to claim 1, wherein said infeed device is configured to introduce an amount of said chemical compound proportional to the temperature difference between said sensed temperature and said predetermined threshold temperature.28. A method according to claim 27, wherein the amount of said chemical compound introduced by said infeed device is between approximately one third of an ounce and approximately 350 ounces.29. A method according to claim 1, wherein said infeed device further comprises a heating device configured to vaporize said chemical compound and produce a chemical compound vapor pressure sufficient to penetrate the substantial entirety of said fuel cell system between the point of said heating device and said respective anode or cathode.30. A method according to claim 1, comprising the additional step of configuring a compressor to facilitate said introduction of said chemical compound into at least one of said anode flowpath or said cathode flowpath.31. A method according to claim 30, wherein said compressor is configured to determine an inlet pressure at said anode, and said chemical compound is introduced downstream of said compressor.32. A method according to claim 30, wherein said compressor is configured to determine an inlet pressure at said cathode, and said chemical compound is introduced downstream of said compressor.33. A method according to claim 1, further comprising the step of selectively operating an auxiliary compressor configured to supply said oxygen to said fuel cell system such that said auxiliary compressor operates simultaneously with the introduction of said chemical compound into said fuel cell system.34. A method according to claim 1, further comprising:an air compressor configured to supply said oxygen to said fuel cell system; and an auxiliary compressor for supplying an auxiliary air flow to said fuel cell system, said auxiliary air compressor configured to operate during said step of introducing said chemical compound such that said auxiliary air flow and said chemical compound are mixed.