The present disclosure relates to a fuel cell system including: an air supply line configured to supply air to a fuel cell stack; a discharge line connected to the fuel cell stack and configured to guide exhaust gas discharged from the fuel cell stack; a discharge adapter connected to the discharge line and configured to discharge the exhaust gas to the outside; and a bypass line having one end connected to the air supply line and the other end connected to the discharge adapter, the bypass line being configured to selectively allow the air to flow from the air supply line to the discharge adapter, thereby effectively reducing a hydrogen concentration in exhaust gas discharged from the fuel cell stack.

Systems and methods are provided for using fuel cell staging to reduce or minimize variations in current density when operating molten carbonate fuel cells with elevated CO.sub.2 utilization. The fuel cell staging can mitigate the amount of alternative ion transport that occurs when operating molten carbonate fuel cells under conditions for elevated CO.sub.2 utilization.

Disclosed is a method of controlling an air supply system for a fuel cell. The air supply system includes a fuel cell stack, an air channel to supply air to an inlet of the fuel cell stack, a gas adsorption unit disposed on the air channel and configured to adsorb oxygen contained in air introduced into the air channel. In particular, the method includes: determining whether a power generation operation of the fuel cell stack is resumed; when the power generation operation of the fuel cell stack is resumed, controlling a voltage source to apply a voltage to the gas adsorption unit; and supplying air to the fuel cell stack through the air channel in a state in which the voltage is applied to the gas adsorption unit.

The present disclosure generally relates to systems and methods for determining, managing, and/or controlling excess hydrogen flow in a system comprising a fuel cell or fuel cell stack and ejector based on the internal state of the ejector.

The present disclosure generally relates to systems and methods for managing and/or excess hydrogen flow in a system comprising a fuel cell or fuel cell stack based on humidity measurements.

The present disclosure generally relates to systems and methods for determining, managing, and/or controlling excess hydrogen flow in a system comprising a fuel cell or fuel cell stack.

Systems and methods are provided for using fuel cell staging to reduce or minimize variations in current density when operating molten carbonate fuel cells with elevated CO.sub.2 utilization. The fuel cell staging can mitigate the amount of alternative ion transport that occurs when operating molten carbonate fuel cells under conditions for elevated CO.sub.2 utilization.

Fuel cell systems configured for efficient byproduct recovery and reuse are disclosed herein. In one embodiment, a fuel cell system includes a reformer configured to reform a fuel containing methane (CH.sub.4) with steam to produce a reformed fuel having methane (CH.sub.4), carbon monoxide (CO), and hydrogen (H.sub.2). The fuel cell system also includes a fuel cell configured to perform an electrochemical reaction between a first portion of the reformed fuel and oxygen (O.sub.2) to produce electricity and an exhaust having carbon dioxide (CO.sub.2), water (H.sub.2O), and a second portion of the reformed fuel. The fuel cell system further includes an oxygen enricher configured to generate an oxygen enriched gas and a combustion chamber configured to combust the second portion of the reformed fuel with the oxygen enriched gas.

A method for increasing safety in the surroundings of an electric vehicle having a fuel cell system and batteries, wherein the vehicle is configured for charging the batteries by power from the fuel cell system and e.g. produces CO2 during this operation, even when the vehicle is turned-off and in a parked situation, wherein the method includes the steps of providing a sensor system having a gas intake and configured for warning against elevated CO2 levels in the surroundings of the vehicle, mounting the sensor system on the vehicle with the gas intake outside the vehicle's cabin, providing an alarm when the sensor system evaluates that the CO2 levels in the surroundings of the vehicle are elevated and surpass a predetermined threshold level.

The present disclosure relates to a fuel cell system including a discharge line configured to discharge exhaust gas, which is discharged from a fuel cell stack, to the outside, and a pneumatic branch line having an outlet end connected to the discharge line, and an inlet end connected to a pneumatic supply unit configured to supply air to a pneumatic part of a mobility vehicle, the pneumatic branch line being configured to selectively supply the air from the pneumatic supply unit to the discharge line, thereby effectively reducing a hydrogen concentration in the exhaust gas discharged from the fuel cell stack.