Abstract: A vehicle includes a fuel-cell system having a fuel cell, a purge valve, and a drain line extending from the purge valve. A controller is programmed to open the purge valve according to a baseline purge routine when the drain line slopes away from the purge valve, and open the purge valve according to an enhanced purge routine when the drain line slopes towards the purge valve.

Abstract: A hydrogen-water separator for a fuel cell includes an upper separation chamber having a first cylindrical sidewall defining an inlet port and a lower collection chamber configured to collect separated water. The collection chamber has a bottom and a second cylindrical sidewall defining a drain port disposed above the bottom. A divider is disposed between the separation chamber and the collection chamber. The divider spans the first cylindrical sidewall and defining one or more openings. An outlet tube is arranged vertically in the separation chamber and having an entrance that is disposed above the divider and below the inlet port.

Abstract: A vehicle includes a fuel-cell system having a fuel cell, a purge valve, and a drain line extending from the purge valve. A controller is programmed to open the purge valve according to a baseline purge routine when the drain line slopes away from the purge valve, and open the purge valve according to an enhanced purge routine when the drain line slopes towards the purge valve.

Abstract: A fuel cell system in a vehicle has a cathode and an anode. A compressor has an inlet and an outlet, the outlet being configured to outlet a compressed air from the compressor. A bypass line is configured to return the compressed air from the outlet to the inlet such that the air returns to the compressor in a loop. A valve is located downstream of the compressor and is operable in a plurality of modes. In a first mode, the valve is configured to block the air from the cathode and return the air via the bypass line. In a second mode, the valve is configured to direct at least some of the air to the cathode. The valve can also be configured to operate in a third mode in which the air is sent to the cathode without going through the bypass line.

Abstract: An airflow control method of an air control system for a fuel cell stack (FCS) includes opening a recirculation valve by a controller to recirculate air through a compressor to increase a temperature of the air prior to entering the FCS to offset a FCS temperature below a predetermined threshold in response to identification to a cold-start event. The recirculation valve may be arranged with the compressor to recirculate air therethrough. The FCS may be arranged with the compressor and recirculation valve to selectively receive air therefrom. A sensor may measure thermal conditions of the FCS. The controller may be programmed to receive signals from the sensor indicating thermal conditions of the FCS, and to operate the recirculation valve based on the signals to recirculate air through the compressor to increase a temperature of the air prior to entering the FCS.

Abstract: An apparatus for measuring at least one of temperature and pressure within a cylinder of an internal combustion engine can include an engine valve and a sensor. The internal combustion engine can include a valvetrain having rocker arm assembly, a camshaft, a valve, and a hydraulic lash adjuster. The engine valve can have a valve head and a valve stem extending from the valve head in an axial direction. The valve head can have a valve face configured to be in pressure communication with an engine cylinder. The valve stem can have an outer surface with a cylindrical portion and a variably-shaped portion. The variably-shaped portion can define a target detectable by the sensor and the sensor can be installed adjacent to the target. Alternatively, the sensor can be positioned to detect a level of force at some point along the valvetrain.

Abstract: An airflow control method of an air control system for a fuel cell stack (FCS) includes opening a recirculation valve by a controller to recirculate air through a compressor to increase a temperature of the air prior to entering the FCS to offset a FCS temperature below a predetermined threshold in response to identification to a cold-start event. The recirculation valve may be arranged with the compressor to recirculate air therethrough. The FCS may be arranged with the compressor and recirculation valve to selectively receive air therefrom. A sensor may measure thermal conditions of the FCS. The controller may be programmed to receive signals from the sensor indicating thermal conditions of the FCS, and to operate the recirculation valve based on the signals to recirculate air through the compressor to increase a temperature of the air prior to entering the FCS.

Abstract: A fuel cell system in a vehicle has a cathode and an anode. A compressor has an inlet and an outlet, the outlet being configured to outlet a compressed air from the compressor. A bypass line is configured to return the compressed air from the outlet to the inlet such that the air returns to the compressor in a loop. A valve is located downstream of the compressor and is operable in a plurality of modes. In a first mode, the valve is configured to block the air from the cathode and return the air via the bypass line. In a second mode, the valve is configured to direct at least some of the air to the cathode. The valve can also be configured to operate in a third mode in which the air is sent to the cathode without going through the bypass line.

Abstract: An apparatus for measuring at least one of temperature and pressure within a cylinder of an internal combustion engine can include an engine valve and a sensor. The internal combustion engine can include a valvetrain having rocker arm assembly, a camshaft, a valve, and a hydraulic lash adjuster. The engine valve can have a valve head and a valve stem extending from the valve head in an axial direction. The valve head can have a valve face configured to be in pressure communication with an engine cylinder. The valve stem can have an outer surface with a cylindrical portion and a variably-shaped portion. The variably-shaped portion can define a target detectable by the sensor and the sensor can be installed adjacent to the target. Alternatively, the sensor can be positioned to detect a level of force at some point along the valvetrain.

Abstract: A multi-stage fuel cell centrifugal compressor system comprising a motor, including a shaft, and a compressor connected to the motor. The compressor includes a first stage inlet; first housing fluidly connected to the first stage inlet; and first impeller driven by the shaft for imparting fluid flow through a first stage of the system. The compressor further includes a first stage outlet fluidly connected to the first housing; a second stage inlet; a second housing fluidly connected to the second stage inlet; a second impeller for imparting fluid flow through a second stage; a second stage outlet fluidly connected to the second housing; and a pipe extending between the first stage outlet and the second stage inlet. The pipe fluidly connects the first stage outlet to the second stage inlet, thereby directing at least a portion of fluid from the first stage to the second stage of the system.

Abstract: The invention provides a fuel cell compressor system that comprises a motor, including a motor shaft driven by the motor; a drive housing at least partially surrounding the motor shaft; a first gear set driven by the motor shaft; a carrier torque tube driven by the first gear set; and an impeller. The impeller includes an impeller shaft driven by the second gear set, so that the impeller shaft is configured to rotate at a speed greater than motor speed. Embodiments of the invention may also be used with a multi-stage compressor that allows, for example, first and second impellers to rotate at different speeds. Embodiments of the invention may also include removal of a gear set driving the carrier torque tube or the impeller shaft, so that the impeller shaft speed is divided between one or more bearings supporting the carrier torque tube and one or more bearings supporting the impeller shaft.