Abstract: A method for removing contaminants in a fuel cell comprises: supplying a hydrogen-based fuel to the anode; supplying a first oxidant to the cathode, wherein the first oxidant comprises at least some sulfur dioxide; drawing a primary load from the fuel cell stack while supplying the hydrogen-based fuel to the anode and the air to the cathode; shutting down the fuel cell when a voltage of the fuel cell is equal to or less than a threshold voltage at which sulfur crosses over from the cathode to the anode, wherein shutting down the fuel cell comprises: performing at least one oxidant starvation while drawing the primary load, removing the primary load after performing the at least one oxidant starvation, and bringing the anode to a high potential after removing the primary load; and thereafter, restarting the fuel cell.

Abstract: A method for removing contaminants in a fuel cell comprises: supplying a hydrogen-based fuel to the anode; supplying a first oxidant to the cathode, wherein the first oxidant comprises at least some sulfur dioxide; drawing a primary load from the fuel cell stack while supplying the hydrogen-based fuel to the anode and the air to the cathode; shutting down the fuel cell when a voltage of the fuel cell is equal to or less than a threshold voltage at which sulfur crosses over from the cathode to the anode, wherein shutting down the fuel cell comprises: performing at least one oxidant starvation while drawing the primary load, removing the primary load after performing the at least one oxidant starvation, and bringing the anode to a high potential after removing the primary load; and thereafter, restarting the fuel cell.

Abstract: Embodiments are disclosed herein that relate to PEM fuel cells comprising membrane-electrode assemblies having plural membrane layers. For example, one disclosed embodiment provides a fuel cell including an anode, a cathode, and a multi-layer membrane disposed between the anode and the cathode, the multi-layer membrane comprising two or more polymer membranes layers. The fuel cell further comprises an electrolyte within the multi-layer membrane.

Abstract: In one embodiment, a method of making an MEA for a fuel cell comprises arranging a cathodic structure on a first surface of a PEM, and arranging an anodic structure on a second surface of the PEM, opposite the first surface, the anodic structure containing more PA per unit volume than the cathodic structure. The method further comprises pressing the cathodic and anodic structures to the PEM to form the MEA.

Abstract: Apparatus and methods of ceasing operation of an electric power generating system improve the cold starting capability of the system. The system comprises a fuel cell stack connectable to an external circuit for supplying power to the external circuit. The stack comprises at least one solid polymer fuel cell, and the system further comprises a fuel passage for directing a fuel stream through the stack and an oxidant passage for directing an oxidant stream through the stack, a sensor assembly connected to the stack for monitoring a parameter indicative of stack performance, a controller for controlling at least one stack operating parameter, and a control system communicative with the sensor assembly and stack operating parameter controller.

Abstract: Apparatus and methods of ceasing operation of an electric power generating system improve the cold starting capability of the system. The system comprises a fuel cell stack connectable to an external circuit for supplying power to the external circuit. The stack comprises at least one solid polymer fuel cell, and the system further comprises a fuel passage for directing a fuel stream through the stack and an oxidant passage for directing an oxidant stream through the stack, a sensor assembly connected to the stack for monitoring a parameter indicative of stack performance, a controller for controlling at least one stack operating parameter, and a control system communicative with the sensor assembly and stack operating parameter controller.

Abstract: Certain fuel cells (e.g., solid polymer electrolyte fuel cells) may temporarily exhibit below normal performance after initial manufacture or after prolonged storage. While normal performance levels may be obtained after operating such fuel cells for a suitable time period, this process can take of order of days to fully complete. However, exposing the cathode to a reductant (e.g., hydrogen) can provide for normal performance levels without the need for a lengthy initial operating period.

Abstract: The electrochemical performance of an ion-exchange membrane in a fuel cell system may be improved by impregnating therein a perfluoroamine. The amine may be primary, secondary or tertiary. Further, the amine is preferably water insoluble or only slightly water soluble. For example, the amine may be perfluorotriamylamine or perfluorotributylamine. Use of such a membrane system within a fuel cell may allow high or low temperature operation (i.e. at temperatures greater than 100° C. or less than 0° C.) as well as operation at low relative humidity.

Abstract: The electrochemical performance of an ion-exchange membrane in a fuel cell system may be improved by impregnating therein a perfluoroamine. The amine may be primary, secondary or tertiary. Further, the amine is preferably water insoluble or only slightly water soluble. For example, the amine may be perfluorotriamylamine or perfluorotributylamine. Use of such a membrane system within a fuel cell may allow high or low temperature operation (i.e. at temperatures greater than 100° C. or less than 0° C.) as well as operation at low relative humidity.

Abstract: The present invention provides a fuel cell that comprises a modified ion exchange membrane. The present invention additionally provides modified membranes produced by in situ polymerisation of monomers, such as aryls, heteroaryls, substituted aryls, substituted heteroaryls or a combination thereof, on and/or within an ion exchange membrane. The modified membranes can exhibit reduced permeability to fuel crossover in comparison to the unmodified membranes, often without a significant increase in ionic resistance. the present invention further provides methods for preparing and testing, or evaluating, the modified membranes and fuel cell comprising the modified membranes.

Abstract: Certain fuel cells (e.g., solid polymer electrolyte fuel cells) may temporarily exhibit below normal performance after initial manufacture or after prolonged storage. While normal performance levels may be obtained after operating such fuel cells for a suitable time period, this process can take of order of days to fully complete. However, exposing the cathode to a reductant (e.g., hydrogen) can provide for normal performance levels without the need for a lengthy initial operating period.

Abstract: Apparatus and methods of ceasing operation of an electric power generating system improve the cold starting capability of the system. The system comprises a fuel cell stack connectable to an external circuit for supplying power to the external circuit. The stack comprises at least one solid polymer fuel cell, and the system further comprises a fuel passage for directing a fuel stream through the stack and an oxidant passage for directing an oxidant stream through the stack, a sensor assembly connected to the stack for monitoring a parameter indicative of stack performance, a controller for controlling at least one stack operating parameter, and a control system communicative with the sensor assembly and stack operating parameter controller.