A fuel-cell stack system includes a stack of electrochemical cells, a fuel gas supply circuit and an oxidant gas supply circuit, a cooling circuit, a micropump, a temperature measurement device, and a controller. The cells are separated by bipolar plates, with each bipolar plate including an anode, a cathode, and an ion-exchange membrane. The cooling circuit, which is structured to enable a coolant fluid to circulate therein, includes a secondary circuit and a primary circuit that is smaller in size than the secondary circuit, with the primary and secondary circuits being isolated from each other by a thermostatic valve. The micropump is installed at an outlet of the stack and enables a volume of water inside the stack to be mixed. The temperature measurement device determines an internal temperature of a core of the stack. The primary circuit is activated when the internal temperature rises above a predetermined threshold.

A device for separating a fluid having a water and gas portion in a fuel cell system includes a fluid inlet an a fluid outlet with an outlet valve. The separating device includes a first reservoir region for collecting the water portion of the fluid. The first reservoir region includes a first outlet to feed the water portion in the direction of the fluid outlet. The separating device also includes a second reservoir region having a second outlet that feeds the water portion in the direction of the fluid outlet so that the first reservoir region 19 is connected in series in terms of flow via the second reservoir region with the fluid outlet. In an installation position of the separating device the first outlet is arranged lower than the second outlet so that deposits of the water portion completely covering the first outlet are prevented from flowing away.

A fuel cell includes end cell heaters each disposed on outer sides of end cells disposed at both ends of the fuel cell stack. The end cell heaters each include a support formed in a plate shape having fuel channels and air channels. A heat generating part is formed in the support. Electricity conduction blocks are coupled to the support.

A constant voltage control method for a fuel cell vehicle includes: determining whether vehicle state information satisfies a cold start condition when the fuel cell vehicle is started; starting constant voltage control on a fuel cell when the vehicle state information satisfies the cold start condition; comparing an RPM of an air blower for supplying air to the fuel cell with a predetermined stop control condition; and terminating the constant voltage control on the fuel cell when the RPM of the air blower satisfies the predetermined control-stopping condition.

A water drain system for a fuel cell vehicle and a control method therefor that derives an expected location where the water drain system for the fuel cell vehicle is expected to be operated. Further, the water drain system for a fuel cell vehicle and the control method therefor operates the water drain system in advance before the vehicle reaches the expected location to discharge the generated water of the fuel cell, so that the freezing at a specific location, such as a parking lot, due to excessive concentration of discharged water, is prevented, and the marketability of the fuel cell vehicle is further improved.

Disclosed herein is an integrated multiple heat exchange device and a fuel cell system using the same. The integrated multiple heat exchange device includes a plurality of heat exchangers for consecutively collecting heat contained in a plurality of gases that are present in the fuel cell system and that have different temperatures, wherein the plurality of heat exchangers are separated from each other, a porous separator is placed between the plurality of heat exchangers such that condensate is collected at a lowermost heat exchanger, and a coolant line penetrates a separator to pass through all the plurality of heat exchangers.

The invention concerns a fuel cell (100), comprising a stack (1) of alternating bipolar plates (113) and membrane electrode assemblies (114) as well as flow channels (104, 105) that are designed between a bipolar plate (113) and a membrane electrode assembly (114) and flow channels (104, 105) that are designed within a bipolar plate (113) as well as a motor vehicle with such a fuel cell. Provision is made that a surface (101) of at least a part of the flow channels (104, 105) that is overflowable by a fluid has, regarding its direction of extension at least in part a hydrophobic segment (101a) and a hydrophilic segment (101b) with regard to a cross-section of the flow channel (104, 105).

A method of operating a fuel cell system comprising a fuel cell assembly configured to generate electrical power from a fuel flow and an oxidant flow, the method comprising a first phase and a subsequent second phase, the first phase comprising; operating the fuel cell assembly with a first stoichiometric ratio of oxidant flow to fuel flow to generate electrical power; providing said generated electrical power to a heater element for heating a coolant for supply to said fuel cell assembly; the second phase comprising; delivering coolant heated in the first phase to the fuel cell assembly; operating the fuel cell assembly with a second stoichiometric ratio of oxidant flow to fuel flow to generate electrical power, the second stoichiometric ratio lower than the first ratio.

The present invention provides a relative humidity and condensed water estimator for a fuel cell and a method for controlling condensed water drain using the same. Here, the relative humidity and condensed water estimator is utilized in control of the fuel cell system involving control of anode condensed water drain by outputting at least two of signals comprising air-side relative humidity, hydrogen-side relative humidity, air-side instantaneous or cumulative condensed water, hydrogen-side instantaneous or cumulative condensed water, instantaneous and cumulative condensed water of the humidifier, membrane water contents, catalyst layer oxygen partial pressure, catalyst layer hydrogen partial pressure, stack or cell voltage, air-side catalyst layer relative humidity, hydrogen-side catalyst layer relative humidity, oxygen supercharging ratio, hydrogen supercharging ratio, residual water in a stack, and residual water in a humidifier.

A power generation stopping method for a fuel cell system including a fuel cell, includes continuing generating electric power by the fuel cell via electrochemical reaction between fuel gas and oxidant gas during a post running period after the fuel cell system is ordered to stop. A coolant is supplied at a first flow rate to the fuel cell during the post running period until temperature of the fuel cell reaches a threshold temperature. A coolant is supplied to the fuel cell at a second flow rate larger than the first flow rate during the post running period after the temperature of the fuel cell has reached the threshold temperature.