Abstract: A fuel cell stack is provided having a plurality of unit cells stacked in a horizontal direction. Each unit cell includes an electrolyte membrane having two surfaces and a peripheral edge, electrodes provided on both surfaces of the electrolyte membrane, frame-shaped members provided on both surfaces of the electrolyte membrane adjacent to the respective electrodes and adjacent the peripheral edge of the electrolyte membrane, separators provided on the electrodes and the frame-shaped members and having a reactant gas passage for supplying a reactant gas to each of the electrodes, and a manifold formed in the stacking direction in fluid communication with the reactant gas passage. The manifold includes a horizontal edge portion in fluid communication with the reactant gas passage.

Abstract: First reinforcing members, having a low modulus of elasticity, are disposed between an electrolyte membrane and second reinforcing members having a high modulus of elasticity, so as not to allow the electrolyte membrane to readily rub against the first reinforcing members as the electrolyte membrane expands and shrinks and to ultimately prevent degradation of the electrolyte membrane.

Abstract: An anode (11a) and a cathode (11b) are provided on either side of an electrolyte membrane (11). A first separator (2) is disposed so as to face the anode (11a), and a second separator (3) is disposed so as to face the cathode (11b). A first sealing member (12) is disposed between the electrolyte membrane (11) and the first separator (2), and a second sealing member (13) is disposed between the electrolyte membrane (11) and the second separator (3). The cross-sectional shape or rubber hardness of the sealing members (12, 13) is varied according to a deformation amount generated in the electrolyte membrane (11) by a sealing reactive force. More specifically, in a site where the deformation amount of the electrolyte membrane (11) is large, either the contact area between the sealing member (12) and the electrolyte membrane (11) is increased, or the rubber hardness of the sealing member (12) is reduced.

Abstract: A fuel cell stack and method of manufacturing a fuel cell stack having a highly anti-corrosive property. The fuel cell stack includes a plurality of cells constructed by interposing an electrolyte membrane electrode assembly between the first and second separators. The first and second separators define gas passages on from both sides of the electrolyte membrane electrode assembly, and a gas manifold is in fluid communication with the gas flow passages through the plurality of stacked cells. Manifold openings for defining the gas manifold are formed in the first and second separators, and the opening areas of the manifold openings are differently sized. The manifold opening inner peripheral end of the first separator has a larger opening area, and is welded to the second separator to form a manifold welding portion.

Abstract: A cell of a fuel cell includes a membrane electrode assembly, and metal first and second separators which sandwich the membrane electrode assembly to form gas flow paths disposed on each side of the membrane electrode assembly. A back surface of the first separator and a back surface of the second separator, the first separator and the second separator being included in adjacent cells, are in contact with each other, thereby forming a temperature-control medium flow path between the first separator and the second separator. In the first separator and the second separator, corrosion-resistant coating layers are provided only on reaction-side surfaces of the first separator and the second separator, the reaction-side surfaces facing the membrane electrode assembly, and portions where the back surface of the first separator is in contact with the back surface of the second separator are joined by welded portions.

Abstract: A fuel cell stack includes a membrane electrode assembly including an electrolyte membrane and electrode catalyst layers sandwiching the electrolyte membrane; metal separators that define gas channels, the metal separators being respectively disposed at both surfaces of the membrane electrode assembly; a current collector from which electromotive force is derived, the current collector being in contact with at least one of the metal separators; and joining parts that join the metal separator to the current collector at portions where the metal separator contacts the current collector.

Abstract: A fuel cell stack (FS) is provided with a plurality of unit cells (1) stacked in a stack direction to form a stack body (3), a pair of fixing members (37, 39) disposed on both sides of the stack body in the stack direction (y), a plurality of rod members (6, 6?, 63, 65, 67, 69), and a plurality of tightening members (41) screwed onto the plurality of rod members to form a plurality of tightening portions, and tightening and rotating directions of the plurality of tightening portions are set such that the tightening and rotating directions of the tightening portions are opposite to that of at least one tightening portion (63, 41).