A fuel cell system includes at least one fuel cell, an oxidant conveyor, a humidifier and at least one water sink. The oxidant conveyor conveys an oxidant through a supply line to the fuel cell. The humidifier introduces water into the oxidant flow. The humidifier is arranged in and/or downstream of the oxidant conveyor and upstream of the fuel cell. The water sink is arranged between the fuel cell and the oxidant conveyor. The water sink is formed and arranged in the supply line in such a way that it prevents liquid water located in the supply line from flowing to the oxidant conveyor.

A shell reinforcing structure for a fuel cell humidifier comprises a main body shell, fixed plates and grating mechanisms, wherein the side edges of the main body shell are fixedly connected with the fixed plates, the side edge of the fixed plate is provided with an end cover, the upper part of the end cover on the left side is fixedly connected with a dry air inlet tube, the left side of the upper part of the main body shell is fixedly connected with a moisture outlet tube, the right side of the upper part of the main body shell is fixedly connected with a moisture inlet tube, the upper end of the end cover on the right side is fixedly connected with a dry air outlet tube, fixed holes are formed in the side edge surface of the fixed plate.

The invention relates to a fuel cell system comprising a stack of electrochemical cells forming a polymer ion-exchange membrane fuel cell (6), a fuel gas supply circuit and an oxidant gas supply circuit.

Said oxidant gas supply circuit comprises a compressor (3) intended to compress the ambient air before it enters the fuel cell (6), and an outlet exhaust (10) intended to discharge the gases leaving the fuel cell.

Said supply circuit is connected to the fuel cell at a first access point (7) and a second access point (8).

The system additionally comprises a switching element (11) that has two positions: a first position in which the outlet of the compressor (3) is connected to the first access point (7), and the second access point (8) is connected to the outlet exhaust (10), and a second position in which the outlet of the compressor (3) is connected to the second access point (8), and the first access point (7) is connected to the outlet exhaust (10).

The system is characterized in that it contains a moisture reservoir positioned in the oxidant gas supply circuit, upstream of the first access point (7).

The invention relates to a method for switching off a fuel cell system (100) having a fuel cell stack (10), that has anode chambers (13) and cathode chambers (12), and a cathode supply (20) having a cathode supply path (21) for supplying an oxygenated cathode operating gas into the cathode chambers (12), a compressor (23) arranged in the cathode supply path(21) and a cathode exhaust path (22) for discharging a cathode exhaust gas from the cathode chambers (12).

The method comprises the steps of:

(a) Maintenance of the cathode chambers (12) under excess pressure while preventing a flow of cathode operating gas through the cathode chambers (12) while keeping the cathode operating gas that is present in the cathode chambers (12) oxygen-depleted;

(b) Expansion of the oxygen-depleted cathode operating gas present in the cathode chambers (12) via the cathode supply path (31) [sic] and/or the cathode exhaust path (22), and

(c) Separation of the cathode chambers (12) from the environment.

A fuel cell apparatus may include a stack, a stack air blower configured to supply external air to the stack, a humidifier configured to extract moisture contained in exhaust air and to supply the extracted moisture to external air supplied to the stack, a first bypass channel configured to allow exhaust air to bypass the humidifier, a first three-way valve controlled to adjust the amount of exhaust air that bypasses the humidifier, and a humidity sensor configured to sense the humidity of external air. The fuel cell apparatus may also include a second bypass channel configured to allow external air to bypass the humidifier, a second three-way valve controlled to adjust the amount of external air that bypasses the humidifier, and a controller configured to control the first three-way valve and the second three-way valve depending on the sensed humidity value of the external air.

An open-cathode-type fuel cell system includes hollow fiber membranes, through which moisture contained in unreacted hydrogen discharged from a fuel cell stack is transferred to air flowing into the fuel cell stack, and an aerial vehicle using the same. The open-cathode-type fuel cell system includes a fuel cell stack configured to generate electricity through a reverse electrolysis reaction using hydrogen and air supplied from the outside, a humidifying structure disposed on one side of the fuel cell stack in order to transfer moisture included in unreacted hydrogen, discharged from the fuel cell stack, to air flowing into the fuel cell stack, and a cooling fan disposed on the other side of the fuel cell stack in order to discharge unreacted air, discharged from the fuel cell stack, and cooling air to the outside. Accordingly, the performance of the air-cooled fuel cell system may be improved.

A humidification device includes a tubular mass exchanger fluidically coupled to receive intake air stream and transfer intake air stream to an intake air inlet of a fuel cell stack. The humidification device includes a housing configured to house the tubular mass exchanger to define a void therebetween. The housing defines at least one housing inlet opening fluidically coupled to direct an exhaust air stream output by the fuel cells tack into the void. The housing defines at least one housing outlet opening fluidically coupled to direct the exhaust air stream away from within the housing. The tubular mass exchanger is configured to extract water vapor from the exhaust air stream and transfer the extracted water vapor to the intake air stream flowing within the tubular mass exchanger to humidify the intake air stream to generate a humidified intake air stream.

A fuel cell vehicle is provided. The fuel cell vehicle includes a fuel cell including a cell stack configured such that a plurality of unit cells is stacked, a drive motor unit disposed below the fuel cell, a purge valve / drain valve assembly configured to discharge unreacted hydrogen and first condensate water flowing together out of the fuel cell, an air exhaust line configured to discharge unreacted oxygen and second condensate water flowing together out of the fuel cell, and a hydrogen exhaust line connecting the purge valve / drain valve assembly to the air exhaust line and disposed so as to avoid interference with the drive motor unit.

A method and system for controlling air flow is arranged to reduce power consumption of an air blower or an air compressor by controlling air flow, enhance stack performance by preventing stack dry-out that is more likely to occur in a low-flow range, and improve durability of the stack by decreasing frequency of exposure to high voltages.

A humidification device includes a humidification section that humidifies taken-in air and a cover that covers the humidification section. A space is provided between the humidification section and the cover. A supply port for sending out humidified air humidified by the humidification section is further provided. The space communicates with the supply port, and the humidified air flows through the space, thereby utilizing air in the space as a heat insulation layer.