Abstract: A fuel cell system includes a stack of fuel cells, a fuel supply line configured to provide an ammonia stream to the stack, and a fuel humidifier configured to humidify the ammonia stream such that a water content of the ammonia stream provided to the stack ranges from about 30% to about 80% by volume.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices and to use EIS to dynamically monitor the performance of a fuel cell system. Embodiment methods may include determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy, determining an ohmic polarization of the set of fuel cells from the impedance, determining a concentration polarization of the set of fuel cells from the impedance, comparing the ohmic polarization of the set of fuel cells to a first threshold, comparing the concentration polarization of the set of fuel cells to a second threshold, and initiating a corrective action when the ohmic polarization is above the first threshold or when the concentration polarization is below the second threshold.

Abstract: A fuel cell system performance recovery method includes applying a DC current load pulse waveform to one or more of the fuel cells for a recovery period sufficient to desorb a contaminant from the one or more fuel cells.

Abstract: A fuel cell system and method, the system including power generating fuel cells disposed in a stack, each power generating fuel cell including an anode, a cathode, and an electrolyte, a sensing fuel cell including an anode, a cathode, and an electrolyte, and a fuel processor configured to purify a fuel provided to the power generating fuel cells and the sensing fuel cell. The anode of the sensing fuel cell is thinner than the anodes of the power generating fuel cells.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices and to use EIS to dynamically monitor the performance of a fuel cell system. Embodiment methods may include determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy, determining an ohmic polarization of the set of fuel cells from the impedance, determining a concentration polarization of the set of fuel cells from the impedance, comparing the ohmic polarization of the set of fuel cells to a first threshold, comparing the concentration polarization of the set of fuel cells to a second threshold, and initiating a corrective action when the ohmic polarization is above the first threshold or when the concentration polarization is below the second threshold.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices and to use EIS to dynamically monitor the performance of a fuel cell system. Embodiment methods may include determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy, determining an ohmic polarization of the set of fuel cells from the impedance, determining a concentration polarization of the set of fuel cells from the impedance, comparing the ohmic polarization of the set of fuel cells to a first threshold, comparing the concentration polarization of the set of fuel cells to a second threshold, and initiating a corrective action when the ohmic polarization is above the first threshold or when the concentration polarization is below the second threshold.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices and to use EIS to dynamically monitor the performance of a fuel cell system. Embodiment methods may include determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy, determining an ohmic polarization of the set of fuel cells from the impedance, determining a concentration polarization of the set of fuel cells from the impedance, comparing the ohmic polarization of the set of fuel cells to a first threshold, comparing the concentration polarization of the set of fuel cells to a second threshold, and initiating a corrective action when the ohmic polarization is above the first threshold or when the concentration polarization is below the second threshold.

Abstract: A fuel cell system and method, the system including power generating fuel cells disposed in a stack, each power generating fuel cell including an anode, a cathode, and an electrolyte, a sensing fuel cell including an anode, a cathode, and an electrolyte, and a fuel processor configured to purify a fuel provided to the power generating fuel cells and the sensing fuel cell. The anode of the sensing fuel cell is thinner than the anodes of the power generating fuel cells.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices and to use EIS to dynamically monitor the performance of a fuel cell system. Embodiment methods may include determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy, determining an ohmic polarization of the set of fuel cells from the impedance, determining a concentration polarization of the set of fuel cells from the impedance, comparing the ohmic polarization of the set of fuel cells to a first threshold, comparing the concentration polarization of the set of fuel cells to a second threshold, and initiating a corrective action when the ohmic polarization is above the first threshold or when the concentration polarization is below the second threshold.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices and to use EIS to dynamically monitor the performance of a fuel cell system. Embodiment methods may include determining an impedance of a set of fuel cells using electrochemical impedance spectroscopy, determining an ohmic polarization of the set of fuel cells from the impedance, determining a concentration polarization of the set of fuel cells from the impedance, comparing the ohmic polarization of the set of fuel cells to a first threshold, comparing the concentration polarization of the set of fuel cells to a second threshold, and initiating a corrective action when the ohmic polarization is above the first threshold or when the concentration polarization is below the second threshold.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices. In an embodiment, a matrix switch may connect each cell of a fuel cell stack individually to an EIS analyzer enabling EIS to be performed on any fuel cell in the fuel cell stack. In a further embodiment, the EIS analyzer may be a multi-channel EIS analyzer, and the combination of the matrix switch and multi-channel EIS analyzer may enable EIS to be performed on multiple fuel cells simultaneously.

Abstract: Systems, methods, and devices of the various embodiments provide a hardware and software architecture enabling electrochemical impedance spectroscopy (“EIS”) to be performed on multiple electrochemical devices, such as fuel cells, at the same time without human interaction with the electrochemical devices. In an embodiment, a matrix switch may connect each cell of a fuel cell stack individually to an EIS analyzer enabling EIS to be performed on any fuel cell in the fuel cell stack.