Metal component for fuel cell and method of manufacturing the same, austenitic stainless steel for polymer electrolyte fuel cell and metal component for fuel cell material and method of manufacturing the same, corrosion-resistant conductive component and method of manufacturing the same, and fuel cell

#A first invention relates to a metal component for fuel cell and a method of manufacturing the same, and also to a fuel cell.

#A second invention relates to an austenitic stainless steel for polymer electrolyte fuel cell, and more specifically to an austenitic stainless steel for polymer electrolyte fuel cell used for conductive separator, current collector and so forth, and a metal component for fuel cell using the same, and also to a fuel cell.

#A third invention relates to a polymer electrolyte fuel cell material such as a metal separator, current collector plate and so forth used in polymer electrolyte fuel cell, and a method of manufacturing the same, and also to a metal component for fuel cell using the same and a fuel cell.

#FIG. 1 is a schematic drawing showing an exemplary configuration of a fuel cell of the first invention;

#FIG. 2A is a first schematic drawing showing an exemplary configuration of a metal component for fuel cell of the first invention;

#FIG. 2B is a second schematic drawing showing an exemplary configuration of the metal component for fuel cell of the first invention;

#FIG. 1 explains the outlines of a metal separator for fuel cell commonly applicable to the first, second, third and fourth inventions, and an exemplary mode of a fuel cell using the same. The fuel cell 1 is a polymer electrolyte fuel cell adopting a polymer electrolyte film 3. More specifically, the polymer electrolyte film 3 may be composed of a fluorine-containing resin containing sulfonic acid groups. The fuel cell 1 has a polymer electrolyte film 3 and a pair of electrodes 2, 4 holding it in between, and therefore has a main cell unit 5 which comprises the polymer electrolyte film 3 and the electrodes 2, 4. The electrodes 2, 4 are brought into contact with the polymer electrolyte film 3 on their first main surfaces 2a, 4a, and plate-formed separators 10 are disposed on the outer sides of the electrodes 2, 4 so as to be brought into contact therewith on their second main surfaces 2b, 4b. Each of the separators 10 plays a role of connecting the main cell units 5 in series, and is disposed so as to supply a fuel gas and oxidizer gas to the main cell unit 5. In this mode of embodiment, the separator 10 corresponds to a metal component for fuel gas of the first invention. It is to be noted that a gasket, not shown in FIG. 1, is disposed between the main cell unit 5 and each of the separators 10 in order to prevent leakage of the fuel gas and oxidizer gas. The main cell unit 5 and the separators 10 composes a unit cell U, and a plurality of the unit cells U are stacked while individually placing a cooling water flowing substrate 11 (composed of a conductive material such as graphite) in between, to thereby configure a fuel cell stack 1. The unit cells U are stacked in, for example, the number of 50 to 400 or around, and respectively on both ends of the stack, there are disposed, as viewed from the side in contact with the unit cell U, a conductive sheet 9, a current collector plate 8, an insulating sheet 7, and a tightening plate 6, to thereby configure a fuel cell stack 1. The current collector plate 8 and a plurality of separators 10 are connected in series, so as to collect current from a plurality of main cell units 5. It is defined now that the above-described unit cell U and fuel cell stack 1 are also included in the concept of the fuel cell in this patent specification. It is to be noted that FIG. 1 shows the individual components, including the conductive sheet 9, current collector plate 8, insulating sheet 7 and tightening plate 6, are illustrated as being departed from each other, but these components in practice are tightened with each other using bolts, for example.

#FIG. 2A to FIG. 2C show the outlines of the separator 10. As shown in FIG. 2A, the separators 10 are shaped in a plate form, have a regular rough formed on the main surfaces thereof, and are disposed so as to make the end sides of the projected portions 14 of the separators 10 contact with the electrodes 2, 4. The recessed portions of each separator 10 serve as gas a flow path 21 (see also FIG. 1) through which a fuel gas or an oxidizer gas is supplied to the electrodes 2, 4. The gas flow path 21 has openings formed on both ends thereof, which serve as a reaction gas inlet port 22 and a reaction gas outlet port 23, respectively. The separators 10 are stacked so that the reaction gas inlet ports 22 and reaction gas outlet ports 23 formed on the individual separators 10 are aligned at the same positions.

#The paragraphs below will describe modes of embodiments specific to the individual inventions.