Abstract: Methods and systems are provided for, applying RF power as part of an RF treatment. The RF power may be applied until a first target temperature is reached, wherein the first target temperature is less than a final target temperature. Responsive to the reaching the first target temperature, application of the RF power may be varied via a feedback control loop until final target temperature is achieved. The application of the RF power may be paused responsive to determining that a temperature spread is greater than a threshold.

Abstract: Methods and systems are provided for applying RF power as part of an RF treatment. Starting the RF treatment may include treating a product positioned within an RF chamber with RF waves. The RF treatment may include estimating a log kill of the product during the RF treatment and terminating the RF treatment responsive to the estimated log kill reaching a log kill threshold.

Abstract: Embodiments are disclosed that relate to preventing electrolyte wicking by bipolar plates in a fuel cell system. In one example, a fuel cell system includes a first membrane-electrode assembly and a second membrane-electrode assembly. The fuel cell system further includes a bipolar plate disposed between the first membrane-electrode assembly and the second membrane-electrode assembly, the bipolar plate comprising a graphite layer and a surface energy adjustment layer.

Abstract: A method is provided for reducing degradation in a fuel cell assembly, including at least one fuel cell with a PBI membrane, during standby, operation. The method may include electrochemically consuming an oxidant from a cathode coupled to the PBI membrane in response to a disconnection of an external load and supplying fuel to remove or electrochemically consume any back-diffused oxidant to the associated fuel cell sufficient to replace or consume the back-diffused oxidant while the external load is removed, and/or also may include controlling a standby temperature of the fuel cell. In this way, it may be possible to avoid increased cell voltage decay associated with degradation of the PBI in a simple and cost effective system.

Abstract: A method is provided for reducing degradation in a fuel cell assembly, including at least one fuel cell with a PBI membrane, during standby, operation. The method may include electrochemically consuming an oxidant from a cathode coupled to the PBI membrane in response to a disconnection of an external load and supplying fuel to remove or electrochemically consume any back-diffused oxidant to the associated fuel cell sufficient to replace or consume the back-diffused oxidant while the external load is removed, and/or also may include controlling a standby temperature of the fuel cell. In this way, it may be possible to avoid increased cell voltage decay associated with degradation of the PBI in a simple and cost effective system.

Abstract: The air-cooled thermal management of a fuel cell stack is disclosed. One disclosed embodiment comprises a cooling plate apparatus for an air-cooled fuel cell stack, where the cooling plate comprises a body configured to receive heat from one or more fuel cells in thermal communication with the body, and airflow channels formed in the body and configured to allow a flow of a cooling air to pass across the body. An insulating structure is disposed in the airflow channels, wherein the insulating structure has decreasing thickness from a cooling air inlet toward a cooling air outlet.

Abstract: A fuel cell power plant (9) includes a stack (10) of fuel cells, each including anodes (11), cathodes (12), coolant channels (13) and either (a) a coolant accumulator (60) and a pump (61) or (b) a condenser and cooler fan. During shutdown, electricity generated in the fuel cell in response to boil-off hydrogen gas (18) powers a controller (20), an air pump (52), which may increase air utilization to prevent cell voltages over 0.85 during shutdown, and either (a) the coolant pump or (b) the cooler fan. Operation of the fuel cell keeps it warm; circulating the warm coolant prevents freezing of the coolant and plumbing. The effluent of the cathodes and/or anodes is provided to a catalytic burner (48) to consume all hydrogen before exhaust to ambient. An HVAC in a compartment of a vehicle may operate using electricity from the fuel cell during boil-off.

Abstract: A method is provided for reducing degradation in a fuel cell assembly, including at least one fuel cell with a PBI membrane, during standby, operation. The method may include electrochemically consuming an oxidant from a cathode coupled to the PBI membrane in response to a disconnection of an external load and supplying fuel to remove or electrochemically consume any back-diffused oxidant to the associated fuel cell sufficient to replace or consume the back-diffused oxidant while the external load is removed, and/or also may include controlling a standby temperature of the fuel cell. In this way, it may be possible to avoid increased cell voltage decay associated with degradation of the PBI in a simple and cost effective system.

Abstract: Embodiments related to fuel cells and membrane-electrode assemblies for fuel cells are disclosed. In one disclosed embodiment, a membrane-electrode assembly includes a catalyzed anode material and a membrane disposed in face-sharing contact with the catalyzed anode material. The membrane comprises mutually interpenetrating first and second phases, the first phase supporting an ionic conduction through the membrane, and the second phase supporting a dimensional structure of the membrane. The membrane-electrode assembly also includes a catalyzed cathode material disposed in face-sharing contact with the membrane, opposite the catalyzed anode material. Two opposing flow plates are also provided, each flow plate configured to distribute a reactant gas to a catalyzed electrode material of the membrane-electrode assembly. Other embodiments provide variants on the membrane-electrode assembly and methods to make the membrane-electrode assembly.

Abstract: The air-cooled thermal management of a fuel cell stack is disclosed. One disclosed embodiment comprises a cooling plate apparatus for an air-cooled fuel cell stack, where the cooling plate comprises a body configured to receive heat from one or more fuel cells in thermal communication with the body, and airflow channels formed in the body and configured to allow a flow of a cooling air to pass across the body. An insulating structure is disposed in the airflow channels, wherein the insulating structure has decreasing thickness from a cooling air inlet toward a cooling air outlet.

Abstract: The extraction of energy from used cooking oil is disclosed. In one embodiment, used cooking oil is admitted from a cooking appliance to an interface, and then to a reactor or a series of reactors where it is reformed into a hydrogen-containing, reformed fuel. The hydrogen-containing, reformed fuel is then admitted to a fuel cell which produces electricity.

Abstract: The extraction of energy from used cooking oil is disclosed. In one embodiment, used cooking oil is admitted from a cooking appliance to an interface, and then to a reactor or a series of reactors where it is reformed into a hydrogen-containing, reformed fuel. The hydrogen-containing, reformed fuel is then admitted to a fuel cell which produces electricity.

Abstract: A method is provided for reducing degradation in a fuel cell assembly, including at least one fuel cell with a PBI membrane, during standby, operation. The method may include electrochemically consuming an oxidant from a cathode coupled to the PBI membrane in response to a disconnection of an external load and supplying fuel to remove or electrochemically consume any back-diffused oxidant to the associated fuel cell sufficient to replace or consume the back-diffused oxidant while the external load is removed, and/or also may include controlling a standby temperature of the fuel cell. In this way, it may be possible to avoid increased cell voltage decay associated with degradation of the PBI in a simple and cost effective system.

Abstract: Embodiments of thermally integrated HT PEM fuel cell systems are disclosed. In one disclosed embodiment, a fuel cell system comprises a fuel cell, a fuel processor configured to form a processed fuel for the fuel cell, and a thermal management system comprising a heat transfer fluid circulation loop that circulates a heat transfer fluid through the fuel cell and through the fuel processing system in a common loop.

Abstract: A fuel cell power plant (9) includes a stack (10) of fuel cells, each including anode (11), cathodes (12), coolant channels (13) and either (a) a coolant accumulator (60) and pump (61) or (b) a condenser and cooler fan. During shutdown, electricity generated in the fuel cell in response to boil-off hydrogen gas (18) powers a controller (20), an air pump (52), which may increase air utilization to prevent cell voltages over 0.85V during shutdown, and either (a) the coolant pump or (b) the cooler fan. Operation of the fuel cell keeps it warm; circulating the warm coolant prevents freezing of coolant and plumbing. The effluent of the cathodes and/or anodes is provided to a catalytic burner (48) to consume all hydrogen before exhaust to ambient. An HVAC in a compartment of a vehicle may operate using electricity from the fuel cell during boil-off.

Abstract: Fuel from a source (6) passes through a hydrogen desulfurizer (8) and a proportioning mixing valve (10) to a CPO (31), the temperature of the output of the CPO being monitored (50) to provide a signal (51) which a controller (52) utilizes to adjust the valve (10). The output of the CPO may be passed through a water gas shift reactor (35) and a preferential CO oxidizer (40) to provide fuel to a fuel cell system (26). The air provided to the valve (10) may be humidified, such as by an enthalpy recovery device (21) receiving the oxidant outflow (24) from the fuel cell system.

Abstract: Method and apparatus for changing the state of operation of a fuel cell, such as starting the fuel cell up or shutting the fuel cell down, are disclosed. An idle load is applied to the fuel cell when the cell temperature is between about normal operating temperature and a transition temperature, and fuel and oxidizer are supplied to the fuel cell commensurate with the power delivered to the idle load. Below the transition temperature, purging/passivation procedures known in the art can be followed, and an open or dummy load applied to the fuel cell. At normal operating temperature or above a service load is applied to the fuel cell.

Abstract: A control method and arrangement (48, 50, 150, I, T, P, FFL) are provided in a fuel cell power plant (10) for regulating (48, FC) fuel flow to a steam-based fuel processing system (FPS) (14) associated with a low-temperature fuel cell stack assembly (12). A portion of the fuel provided by the FPS (14) is used to provide steam for the FPS. The fuel flow to the FPS is regulated as a function of the power demand (I) on the fuel cell (12) and at least the enthalpy of the steam (P, T), such that the steam enthalpy is regulated to meet increases and decreases in power demand without exceeding steam pressure limits. In addition to reliance on-steam pressure (P) as a fundamental measure of steam enthalpy, the control may additionally use reaction temperature (T) at, or in, a reformer, such as a catalytic steam reformer (132), to regulate fuel flow and thus, steam enthalpy.

Abstract: A control method and arrangement (48, 50, 150, I, T, P, FFL) are provided in a fuel cell power plant (10) for regulating (48, FC) fuel flow to a steam-based fuel processing system (FPS) (14) associated with a low-temperature fuel cell stack assembly (12). A portion of the fuel provided by the FPS (14) is used to provide steam for the FPS. The fuel flow to the FPS is regulated as a function of the power demand (I) on the fuel cell (12) and at least the enthalpy of the steam (P, T), such that the steam enthalpy is regulated to meet increases and decreases in power demand without exceeding steam pressure limits. In addition to reliance on-steam pressure (P) as a fundamental measure of steam enthalpy, the control may additionally use reaction temperature (T) at, or in, a reformer, such as a catalytic steam reformer (132), to regulate fuel flow and thus, steam enthalpy.

Abstract: A fuel cell power plant having a plurality of functionally integrated components including a fuel cell assembly provided with a fuel stream, an oxidant stream and a coolant stream. The fuel cell power plant functionally integrates a mass and heat recovery device for promoting a transfer of thermal energy and moisture between a first gaseous stream and a second gaseous stream, and a burner for processing the fuel exhausted from the fuel cell assembly during operation thereof. A housing chamber is utilized in which the oxidant stream exhausted from the fuel cell assembly merges with a burner gaseous stream exhausted from the burner. The resultant airflow from the common chamber is directed back to the mass and heat recovery device as the first gaseous stream.