This fuel cell stack activation method is a method for activating a fuel cell stack provided with a solid polymer-containing electrolyte membrane, an anode electrode, and a cathode electrode, the method comprising: a first current application step for applying a current by electrically connecting the two electrodes via an external electrical load in a state in which a potential difference is generated between the two electrodes by supplying air as a cathode-side gas to the cathode electrode while supplying hydrogen gas as an anode-side gas to the anode electrode; and a second current application step for applying a current by electrically connecting the two electrodes via an external electrical load in a state in which a potential difference is generated between the two electrodes by supplying nitrogen gas as a cathode-side gas to die cathode electrode while supplying hydrogen gas as an anode-side gas to the anode electrode.

A fuel cell is operated with high power such that which a humidified gas and a dry gas are selectively supplied as oxidant to a cathode of the fuel cell. This method includes (S1) supplying a humidified gas while a power is constantly maintained or until the power begins to decrease; (S2) after supplying the humidified gas, supplying a dry gas to obtain a greater power than an average power of the step (S1); and (S3) after obtaining a predetermined power in the step (S2), repeatedly supplying a humidified gas in case the power decreases and supplying a dry gas in case the power decreases again afterwards, thereby increasing the power such that the predetermined power is maintained. This method provides an optimal operating condition to a fuel cell, thereby ensuring a high power.

A fuel cell apparatus (10) and method (50) of operating a fuel cell are provided. The fuel cell apparatus (10) includes a fuel cell assembly (12) having a first outlet (26) and a first vessel (34) coupled to the first outlet (26) and forming a first dead end. The first vessel (34) is arranged to receive and hold a portion of a first reactant and water when a supply of the first reactant is being fed to the fuel cell assembly (12) and to return the first reactant in the first vessel (34) to the fuel cell assembly (12) via the first outlet (26) when the supply of the first reactant to the fuel cell assembly (12) is cut off.

A humidifier comprises hollow shell and humidifier core. The humidifier core includes a transfer sheet, a plurality of first channels, and a plurality of second channels. The transfer sheet comprises a permeable material having a plurality of sections and a plurality of layers of spacing materials. The plurality of first channels are configured to allow air flow in a first direction and to prevent airflow in a second direction that is different from the first direction. The plurality of second channels are configured to allow air flow in the second direction and to prevent airflow in the first direction. The humidifier comprises a stack of alternating first channels and second channels, and the first channels are configured to transfer liquid from air flowing in at least one of the first channels to air flowing in at least one of the second channels. The humidifier is suitable for use in fuel cell stack.

A method of manufacturing gas diffusion layers (GDL) with a defined pattern of hydrophobic and hydrophilic regions is used to produce electrically conductive porous materials with distributed wettability. The method includes a) Coating the external and internal surfaces of a porous base material made of carbon fiber or Titanium with Fluoroethylene-Propylene (FEP) and/or perfluoroalkoxy (PFA) and/or Ethylene-Tetrafluoroethylene (ETFE) or any other hydrophobic polymer; b) Exposing the coated material to irradiation through a blocking mask such that only parts of the coated porous material are exposed; and c) Immersing the previously exposed material in a monomer solution and heating to a temperature higher than 45° C., resulting in the graft co-polymerization of monomers on the FEP layer.

A fuel cell control method includes detecting a state value indicating a state in a fuel cell during an operation of the fuel cell. The fuel cell includes a membrane electrode assembly and a separator stacked on the membrane electrode assembly. The membrane electrode assembly includes a solid polymer electrolyte membrane sandwiched between an anode electrode and a cathode electrode. It is determined whether a liquid connects the solid polymer electrolyte membrane and the separator based on the state value detected. The fuel cell is dried in a case where it is determined that the liquid connects the solid polymer electrolyte membrane and the separator.

A humidifier includes plural separators each formed in a plate shape, the separator including a flow path on each of a front side and a back side thereof, and a water exchanging film sandwiched between the separators at a boundary thereof which are adjacent to each other in a state where the plural separators are stacked on each other. Humidified gas flows in one of the flow paths facing each other with the water exchanging film therebetween, and dry gas flows in the other of the flow paths. The water exchanging film is formed in an elongated shape, and different areas of the water exchanging film are sandwiched by the separators at plural boundaries thereof.

A fuel cell startup apparatus and method reduces high-voltage generation and corrosion of a cathode electrode that may occur because the density of oxygen is locally high in a cell near a central flow distributor after long-term parking of a fuel-cell vehicle. To this end, density control gas is selectably injected into a fuel supply line prior to supply of reaction gas of hydrogen and air in a fuel cell startup process after long-term parking to forcedly mix anode-side gas in the fuel supply line and the cell with the density control gas.

A method for manufacturing a heat exchanger includes: providing a porous material that has a porosity of about 30% to about 80%; forming an oxide layer on a surface of the porous material by heat treating the porous material at a temperature in a range of 600° C. to 900° C. for a time period in a range of 8 hours to 12 hours in air; and integrating the porous material into a cold side flow passage of the heat exchanger.

A method of operating a water electrolysis and electricity generating system includes, at a time of switching from the water electrolysis mode to the electricity generating mode, a water electrolysis stopping step, a purging step and an electricity generation starting step. In the purging step after the water electrolysis stopping step, an oxygen-containing gas is caused to flow from an oxygen-containing gas flow path to a first gas-liquid separator via an oxygen-containing gas introduction flow path, a first supply flow path, a first inlet port member, a first fluid flow path, a first outlet port member, and a first lead-out flow path. In the electricity generation starting step after the purging step, the cell member is caused to generate electricity based on a predetermined required load value.