Abstract: The present disclosure generally relates to systems and methods for detecting a hydrogen leak in a fuel cell system including initiating a shutdown process of a fuel cell stack in the fuel cell system by a controller, measuring a volume of hydrogen in a reservoir, pulsing a volume of hydrogen into the reservoir or pulsing hydrogen directly into the fuel cell stack if the volume of hydrogen is insufficient to sustain a voltage discharge process during the shutdown process, making the fuel cell system enter a discharge state by the controller, wherein hydrogen and oxygen in the fuel cell stack are consumed in an electrochemical reaction to discharge voltage in the fuel cell stack, measuring a rate of the voltage discharge by the controller, and detecting the hydrogen leak based on the rate of the voltage discharge or via negative pressure measurements made at the anode inlet.

Abstract: The present disclosure generally relates to systems and methods for detecting a hydrogen leak in a fuel cell system including initiating a shutdown process of a fuel cell stack in the fuel cell system by a controller, measuring a volume of hydrogen in a reservoir, pulsing a volume of hydrogen into the reservoir or pulsing hydrogen directly into the fuel cell stack if the volume of hydrogen is insufficient to sustain a voltage discharge process during the shutdown process, making the fuel cell system enter a discharge state by the controller, wherein hydrogen and oxygen in the fuel cell stack are consumed in an electrochemical reaction to discharge voltage in the fuel cell stack, measuring a rate of the voltage discharge by the controller, and detecting the hydrogen leak based on the rate of the voltage discharge or via negative pressure measurements made at the anode inlet.

Abstract: The present disclosure generally relates to systems and methods for purging water from a fuel cell stack system depending on its tilt angle and tilt location. The fuel cell stack system includes a fuel cell stack with a first corner, a second corner, a third corner and a fourth corner, a tilt sensor located on the fuel cell stack, wherein the tilt sensor is operable to detect tilt location of the fuel cell stack, and wherein the tilt location is the first, second, third or fourth corner of the fuel cell stack, a first purge valve system and a second purge valve system for removing water from an anode exhaust, and a controller.

Abstract: The present disclosure generally relates to systems and methods for assessing the health of a fuel cell stack including collecting fuel cell stack operating data by a controller including stack voltage data and cell voltage monitoring data and determining the trust in the collected data, processing stack voltage data and cell voltage monitoring data by the controller to identify bad channels and weak cells amongst fuel cells included in the fuel cell stack, tracking the state of health of the fuel cell stack by the controller, and assessing the health of the fuel cell stack by the controller.

Abstract: The present disclosure generally relates to systems and methods for operating a shutdown process in a fuel cell system including connecting a passive electrical load to a fuel cell stack in the fuel cell system before initiating the shutdown process, disconnecting a DC-DC converter by a system controller, initiating nitrogen blanketing after a current passing through the DC-DC converter is reduced to about zero, ensuring water content in the fuel cell stack is about zero, and sending a signal to the system controller to initiate the shutdown process.

Abstract: The present disclosure generally relates to systems and methods for detecting a hydrogen leak in a fuel cell system including initiating a shutdown process of a fuel cell stack in the fuel cell system by a controller, measuring a volume of hydrogen in a reservoir, pulsing a volume of hydrogen into the reservoir or pulsing hydrogen directly into the fuel cell stack if the volume of hydrogen is insufficient to sustain a voltage discharge process during the shutdown process, making the fuel cell system enter a discharge state by the controller, wherein hydrogen and oxygen in the fuel cell stack are consumed in an electrochemical reaction to discharge voltage in the fuel cell stack, measuring a rate of the voltage discharge by the controller, and detecting the hydrogen leak based on the rate of the voltage discharge or via negative pressure measurements made at the anode inlet.

Abstract: The present disclosure generally relates to systems and methods for purging water or gas from a fuel cell system. The fuel cell system may include a multi-phase valve system and/or a separate valve system.