Abstract: A cell assembly has reactant gas passages connected in series in first and second unit cells, and oxygen-containing gas inlets, intermediate oxygen-containing gas inlets, oxygen-containing gas outlets, intermediate oxygen-containing gas outlets which are defined in the first and second unit cells. The oxygen-containing gas inlets and the intermediate oxygen-containing gas inlets are disposed upwardly of the oxygen-containing gas outlets and the intermediate oxygen-containing gas outlets. The oxygen-containing gas outlets and the intermediate oxygen-containing gas outlets are disposed at least partly below electric energy generating surfaces of the first and second unit cells.

Abstract: A fuel cell includes a membrane electrode assembly and first and second metal plates sandwiching the membrane electrode assembly. The first metal plate has positioning ribs for positioning the outer region of the membrane electrode assembly. The first and second metal plates are positioned in alignment with each other by the first and second insulating bushings attached to first and second positioning holes of the first and second metal plates. Further, the first and second metal plates sandwiching the membrane electrode assembly are fastened together by a plurality of metal clip members.

Abstract: A fuel cell includes a plurality of fuel cell units. Each fuel cell unit includes an electrode assembly having electrodes and an electrolyte, a pair of separators, and gas sealing members. At least two of the fuel cell units include at least two electrode assemblies and at least three separators. In each of the separators, reaction gas communication ports are provided. In one of the separators of one of the stacked fuel cell units that is located at the end in a direction of stacking, through paths are formed. In one of the separators of one of the stacked fuel cell units that is located at the other end in the direction of stacking, reaction gas communication paths are formed. Both the through paths and the reaction gas communication paths are formed in all separators that are located between two fuel cell units that are located at the ends.

Abstract: A fuel cell is formed by stacking a membrane electrode assembly and separators alternately. Each of the separators includes first and second metal plates. A coolant flow field is formed between the first metal plate of the fuel cell and the second metal plate of the adjacent fuel cell. A folded section is provided around a coolant supply passage by folding the second metal plate. The folded section forms an inlet which enlarges the sectional area of an opening as a fluid passage between the coolant supply passage and the coolant flow field.

Abstract: A fuel cell stack is provided with an outlet side oxygen-containing gas communication hole. First and second oxygen-containing gas flow passage grooves are provided in the direction of the gravity while meandering in the horizontal direction on a surface of a first separator. The second oxygen-containing gas flow passage grooves communicate with the outlet side oxygen-containing gas communication hole via second oxygen-containing gas connecting flow passages. A porous water-absorbing tube, which is used to discharge water to the outside of the fuel cell stack in accordance with the capillary phenomenon and the difference in pressure of air, is provided for the is outlet side oxygen-containing gas communication hole.

Abstract: A casing includes end plates and first through fourth side plates. The first and third side plates are short, and the second and fourth side plates are long. At least cross sectional areas or shapes of the first through fourth side plates are determined such that the sides of the end plates have substantially the same deflection in the stacking direction.

Abstract: A fuel cell includes a membrane electrode assembly and first and second metal separators sandwiching the membrane electrode assembly. A first cell voltage terminal for detecting a voltage generated in the membrane electrode assembly is formed integrally with an outer region of the first metal separator. The first cell voltage terminal extends outwardly from the first metal separator. A first seal member covers the outer region of the first metal separator, and includes a first extension seal which covers the first cell voltage terminal to a position near a tip end of the first cell voltage terminal.

Abstract: A power generation cell includes a membrane electrode assembly and first and second metal separators sandwiching the membrane electrode assembly. Ridge members are formed integrally on the second metal separator, and these ridge members contact a first seal member of the first metal separator under pressure to form an inlet connection channel and an outlet connection channel. The coolant supply passage and the coolant flow field are connected through the inlet connection channel and the coolant discharge passage and the coolant flow field are connected through the outlet connection channel.

Abstract: The present invention provides a fuel cell comprising a pair of separators sandwiching outsides of a membrane electrode assembly composed of a pair of electrodes provided on both sides of a solid polymer electrolyte membrane, an outer seal member sandwiched by a pair of separators at a position surrounding an outer periphery of the membrane electrode assembly, an inner seal member sandwiched by one of the pair of separators and an outer periphery of the electrolyte membrane, and a backing member opposing to the inner seal member interposing the electrolyte membrane, wherein steps are formed at contact surfaces of the inner seal member and the outer seal member on one of the pair of separators.

Abstract: A first unit cell of a fuel cell stack has a first joint body sandwiched between a first separator and a second separator. The second separator has a first metal sheet having a region where grooves and ridges alternate with each other and a second metal sheet having a region where grooves and ridges alternate with each other, and a leaf spring interposed between the first and second metal sheets. The leaf spring is held against crests of the ridges of the first and second metal sheets. The grooves of the first metal sheet face the ridges of the second metal sheet across the leaf spring, and the ridges of the first metal sheet face the grooves of the second metal sheet across the leaf spring.

Abstract: A fuel cell is reduced in size and weight while the respective communication passages are reliably sealed by the respective sealing members between separators and an electrode assembly. Separators of a fuel cell is provided with communication holes for a reaction gas and cooling medium provided in the outer side of gas sealing members, and with a communication passage that detours around the gas sealing members in the thickness direction of the separators and connects gas communication passages with the reaction gas communication hole. A cooling surface sealing member that seals off the cooling medium communication passage from the reaction gas communication hole is located at a position that is shifted from the communicating passage towards the communication hole side.

Abstract: A fuel cell is provided that has a sufficient sealing performance while having a restrained dimension in the stacking direction thereof. The fuel cell is formed by stacking a plurality of fuel cell units, each fuel cell unit comprising: an electrode assembly formed by disposing electrodes on both sides of an electrolyte; a pair of separators that sandwich the electrode assembly in the thickness direction thereof; and gas sealing members that are disposed at an outer peripheral portion of the electrode assembly, and that seal respective reaction gas flow passages that are formed between each separator and the electrode assembly and are bounded by the separators and electrode assembly.

Abstract: A membrane electrode assembly includes an anode, a cathode, and a solid polymer electrolyte membrane interposed between the anode and the cathode. The membrane electrode assembly has a substantially rectangular shape as a whole. Extensions extend outwardly from four corners of the membrane electrode assembly. Each of the extensions has an inclined end to have a substantially triangle shape. The membrane electrode assembly has a substantially rectangular power generation area.

Abstract: A cell assembly includes a first unit cell and a second unit cell stacked to each other. The first unit cell includes a first unified body, and the second unit cell includes a second unified body. In the cell assembly, oxidizing gas passages and fuel gas passages are provided in parallel along the first and second unit cells.

Abstract: A seal member is formed integrally on surfaces of a metal separator of a fuel cell. The seal members include an outer seal provided near the outer edge of the separator, and an inner seal spaced inwardly from the outer seal by a predetermined distance. When a load is applied to the outer seal and the inner seal in a stacking direction, the outer seal and the inner seal are deformed substantially equally in the stacking direction to the same extent.

Abstract: A fuel cell stack includes a box-shaped casing and a stack body in the box-shaped casing. The stack body is formed by stacking a plurality of unit cells. The casing includes end plates, a plurality of side plates, angle members, and coupling pins. The angle members couple adjacent ends of the side plates. The coupling pins couple the end plates and the side plates.

Abstract: A fuel cell is provided that is reduced in both size and weight while securing a sealed state of respective flow passages by respective sealing members between separators and an electrode assembly. In this fuel cell, there are provided in each of the separators communication ports for reaction gases and cooling medium that are provided outward from gas sealing members, and communication paths that detour around the gas sealing members in the thickness direction of the separators and connect the reaction gas communication ports with gas flow passages. A cooling surface sealing member that seals off the cooling medium flow passage from the reaction gas communication ports is placed at a position shifted from the communication paths towards the communication holes.

Abstract: A fuel cell that is small and light has separators having communication ports for reaction gases and cooling medium that are provided on an outer side of gas sealing members so as to penetrate each of the separators, and communication paths that detour around the gas sealing members in the thickness direction of the separators and connect the reaction gas communication ports with reaction gas flow passages. Furthermore, support members are provided to support the portions of the separators at which the gas sealing members and the cooling surface sealing member are disposed so as to be offset with respect to each other as viewed in the stacking direction.

Abstract: A fuel cell stack is provided with an outlet side oxygen-containing gas communication hole. First and second oxygen-containing gas flow passage grooves are provided in the direction of the gravity while meandering in the horizontal direction on a surface of a first separator. The second oxygen-containing gas flow passage grooves communicate with the outlet side oxygen-containing gas communication hole via second oxygen-containing gas connecting flow passages. The lowest position of the second oxygen-containing gas flow passage grooves 44 in the direction of gravity is higher than the bottom of the outlet side oxygen-containing gas communication hole 38b by the height h.

Abstract: The present invention provides a fuel cell comprising a pair of separators sandwiching outsides of a membrane electrode assembly composed of a pair of electrodes provided on both sides of a solid polymer electrolyte membrane, an outer seal member sandwiched by a pair of separators at a position surrounding an outer periphery of the membrane electrode assembly, an inner seal member sandwiched by one of the pair of separators and an outer periphery of the electrolyte membrane, and a backing member opposing to the inner seal member interposing the electrolyte membrane, wherein steps are formed at contact surfaces of the inner seal member and the outer seal member on one of the pair of separators.