(US5798186-A)      The operation of a fuel cell stack for electric power generation involves supplying current from the fuel cell stack to an external circuit such that at least a portion of a membrane electrode assembly which has a temperature below the freezing point of water is raised above the freezing point. The stack consists of 1 fuel cell, each comprising the membrane electrode assembly consisting of anode and cathode, a water permeable ion exchange membrane between anode and cathode, and fuel and oxidant supply streams. Also claimed are: (1) a method of ceasing and commencing operation of the fuel cell stack by interrupting the current flow, reducing the temperature of the membrane electrode assembly below the freezing point of water, then carrying out the above process; and (2) a freeze tolerant fuel cell system.    ADVANTAGE -   The fuel cell does not need to be heated before operation.    (GB2330686-A)      The operation of a fuel cell stack for electric power generation involves supplying current from the fuel cell stack to an external circuit such that at least a portion of a membrane electrode assembly which has a temperature below the freezing point of water is raised above the freezing point. The stack consists of 1 fuel cell, each comprising the membrane electrode assembly consisting of anode and cathode, a water permeable ion exchange membrane between anode and cathode, and fuel and oxidant supply streams. Also claimed are: (1) a method of ceasing and commencing operation of the fuel cell stack by interrupting the current flow, reducing the temperature of the membrane electrode assembly below the freezing point of water, then carrying out the above process; and (2) a freeze tolerant fuel cell system.    ADVANTAGE -   The fuel cell does not need to be heated before operation.    (GB2330686-B)      The operation of a fuel cell stack for electric power generation involves supplying current from the fuel cell stack to an external circuit such that at least a portion of a membrane electrode assembly which has a temperature below the freezing point of water is raised above the freezing point. The stack consists of 1 fuel cell, each comprising the membrane electrode assembly consisting of anode and cathode, a water permeable ion exchange membrane between anode and cathode, and fuel and oxidant supply streams. Also claimed are: (1) a method of ceasing and commencing operation of the fuel cell stack by interrupting the current flow, reducing the temperature of the membrane electrode assembly below the freezing point of water, then carrying out the above process; and (2) a freeze tolerant fuel cell system.    ADVANTAGE -   The fuel cell does not need to be heated before operation.    (JP2000512068-W)      The operation of a fuel cell stack for electric power generation involves supplying current from the fuel cell stack to an external circuit such that at least a portion of a membrane electrode assembly which has a temperature below the freezing point of water is raised above the freezing point. The stack consists of 1 fuel cell, each comprising the membrane electrode assembly consisting of anode and cathode, a water permeable ion exchange membrane between anode and cathode, and fuel and oxidant supply streams. Also claimed are: (1) a method of ceasing and commencing operation of the fuel cell stack by interrupting the current flow, reducing the temperature of the membrane electrode assembly below the freezing point of water, then carrying out the above process; and (2) a freeze tolerant fuel cell system.    ADVANTAGE -   The fuel cell does not need to be heated before operation.