Abstract: A fuel cell system includes an air compressor having an inlet fluidly coupled to ambient, a humidifier fluidly coupled to an outlet of the air compressor, a mass airflow sensor disposed downstream of the air compressor and upstream of the humidifier, a fuel cell stack having a cathode inlet fluidly coupled to an outlet of the humidifier, a differential pressure flow sensor disposed downstream of the humidifier and upstream of the cathode inlet of the fuel cell stack, and a controller programmed to control at least one of the air compressor and the fuel cell stack in response to humidity of airflow to the cathode inlet of the fuel cell stack as indicated by signals from at least the mass airflow sensor and the differential pressure flow sensor.

Abstract: A fuel cell system includes a stack of proton exchange membrane (PEM) fuel cells defining a body, the body including a coolant inlet and coolant outlet, a cathode inlet and cathode outlet corresponding to a cathode, an anode inlet and an anode outlet corresponding to an anode. The fuel cell system also includes a cathode humidifier fluidly connected to the cathode inlet to provide a humidified inlet stream to the cathode inlet, an oxygen sensor positioned upstream of the cathode inlet and downstream of the cathode humidifier, and configured to measure oxygen content of the humidified inlet stream, and a controller connected to the cathode humidifier and the oxygen sensor and configured to operate the cathode humidifier based on the oxygen content of the humidified inlet stream.

Abstract: A fuel cell system includes a stack of proton exchange membrane (PEM) fuel cells defining a body, the body including a coolant inlet and coolant outlet, a cathode inlet and cathode outlet corresponding to a cathode, an anode inlet and an anode outlet corresponding to an anode. The fuel cell system also includes a cathode humidifier fluidly connected to the cathode inlet to provide a humidified inlet stream to the cathode inlet, an oxygen sensor positioned upstream of the cathode inlet and downstream of the cathode humidifier, and configured to measure oxygen content of the humidified inlet stream, and a controller connected to the cathode humidifier and the oxygen sensor and configured to operate the cathode humidifier based on the oxygen content of the humidified inlet stream.

Abstract: A vehicle includes a high-voltage bus and an electric motor electrically coupled to the bus. The vehicle further includes a fuel cell system electrically coupled to the bus. The fuel cell system includes a fuel stack and a reservoir in fluid connection with the fuel stack. The reservoir has a concave, generally conically-shaped bottom wall extending upwardly into and forming an apex within a cavity of the reservoir. The reservoir further includes a valve receptacle extending from a sidewall of the reservoir into the cavity of the reservoir. The valve receptacle defines a drain aperture and an outlet orifice having a bottom edge disposed proximate the apex of the bottom wall. The fuel cell system further includes a drain tube in fluid communication with the drain aperture and a control valve disposed within the valve receptacle and adapted to control fluid communication between the outlet orifice and the drain aperture.

Abstract: A fuel cell anode purge line includes an elongated water-scavenging body having a single inlet portion, a single outlet portion having an outlet valve, and a scavenged reservoir configured to accumulate water and fluidly connect the inlet and outlet portions so as to direct a flow of purge gas from the inlet portion through the reservoir such that the purge gas entrains the water in the flow and transfers the water towards the outlet valve.

Abstract: A vehicle includes a high-voltage bus and an electric motor electrically coupled to the bus. The vehicle further includes a fuel cell system electrically coupled to the bus. The fuel cell system includes a fuel stack and a reservoir in fluid connection with the fuel stack. The reservoir has a concave, generally conically-shaped bottom wall extending upwardly into and forming an apex within a cavity of the reservoir. The reservoir further includes a valve receptacle extending from a sidewall of the reservoir into the cavity of the reservoir. The valve receptacle defines a drain aperture and an outlet orifice having a bottom edge disposed proximate the apex of the bottom wall. The fuel cell system further includes a drain tube in fluid communication with the drain aperture and a control valve disposed within the valve receptacle and adapted to control fluid communication between the outlet orifice and the drain aperture.

Abstract: A vehicle is powered by a fuel cell system. The fuel cell system includes a water separator with a reservoir for accumulating water from the fuel cell system. A drain valve is coupled to a drain channel defined by the reservoir and is configured to drain water from the reservoir when opened. A cartridge heater is positioned within the drain channel proximate the drain valve. A controller is configured to activate the cartridge heater for a duration that varies based on an ambient temperature.

Abstract: A knock-out assembly for a fuel cell purge line includes a separator, a valve and a tube. The separator has a drain fluidly coupled to a body attached to an anode. The valve has a first inlet attached to and in fluid communication with the drain. The tube is disposed within the drain and the first inlet, and is configured to extend into the body and away from the drain.

Abstract: A fuel cell system includes a fuel cell stack, a separator and a scavenging reservoir. The separator is downstream of and in fluid communication with the fuel cell stack. The scavenging reservoir is downstream of and in fluid communication with the separator. The scavenging reservoir includes an inlet, an outlet, and a partially toroidal middle interconnecting the inlet and outlet. The partially toroidal middle has a radius of curvature, a torus diameter, and an arc length selected such that a minimum volume of liquid necessary to completely block passage of fluid therethrough is the same over a range of tilt angles defined by the minimum volume of liquid, the radius of curvature, and torus diameter. The arc length is based on the radius of curvature and the torus diameter.

Abstract: A fuel cell anode purge line includes an elongated water-scavenging body having a single inlet portion, a single outlet portion having an outlet valve, and a scavenged reservoir configured to accumulate water and fluidly connect the inlet and outlet portions so as to direct a flow of purge gas from the inlet portion through the reservoir such that the purge gas entrains the water in the flow and transfers the water towards the outlet valve.