The invention relates to a component (8) comprising a substrate made of chromia-former metal alloy (82), the basic element of which is iron (Fe) or nickel (Ni), wherein the substrate has two main planar faces. According to the invention: one of the main planar faces is coated with a coating comprising a thick layer of ceramic (80), grooved to delimit channels (800) suitable for the distribution and/or collection of gases, such as H.sub.2O water vapour, H.sub.2 or air, and/or one of the main planar faces is coated with a thick metal layer (81), grooved to delimit channels (810) suitable for the distribution and/or collection of gases, such as H.sub.2O water vapour, H.sub.2, O.sub.2 or draining gas. The invention also relates to the associated production processes.

Method for forming a metallic component surface to achieve lower electrical contact resistance. The method comprises modifying a surface chemical composition and creating a micro-textured surface structure of the metallic component that includes small peaks and/or pits. The small peaks and pits have a round or irregular cross-sectional shape with a diameter between 10 nm and 10 microns, a height/depth between 10 nm and 10 microns, and a distribution density between 0.4 million/cm.sup.2 and 5 billion cm.sup.2.

Method for forming a metallic component surface to achieve lower electrical contact resistance. The method comprises modifying a surface chemical composition and creating a micro-textured surface structure of the metallic component that includes small peaks and/or pits. The small peaks and pits have a round or irregular cross-sectional shape with a diameter between 10 nm and 10 microns, a height/depth between 10 nm and 10 microns, and a distribution density between 0.4 million/cm.sup.2 and 5 billion cm.sup.2.

Improved contact between interconnect and oxygen electrode material in solid oxide cell (SOC) stacks is achieved through a contact point between the oxygen electrode or an oxygen-side contact layer of the SOC and a coated ferritic stainless steel interconnect in the SOC stack, where the coating on the metallic interconnect comprises Cu.

Improved contact between interconnect and oxygen electrode material in solid oxide cell (SOC) stacks is achieved through a contact point between the oxygen electrode or an oxygen-side contact layer of the SOC and a coated ferritic stainless steel interconnect in the SOC stack, where the coating on the metallic interconnect comprises Cu.

Solid polymer electrolyte fuel cell stacks require a significant nominal compressive loading for proper operation and sealing. This loading is typically provided using relatively thick end plates and tight straps. In certain fuel cell applications, one or more solid polymer electrolyte fuel cell stacks are secured in larger enclosures (e.g. for isolation and crashworthiness in automotive applications). The enclosures however can themselves be sturdy enough to provide the necessary loading on the fuel cell stacks within. The present invention takes advantage of that to allow for use of thinner end plates and/or weaker straps which would otherwise be insufficient for use.

Solid polymer electrolyte fuel cell stacks require a significant nominal compressive loading for proper operation and sealing. This loading is typically provided using relatively thick end plates and tight straps. In certain fuel cell applications, one or more solid polymer electrolyte fuel cell stacks are secured in larger enclosures (e.g. for isolation and crashworthiness in automotive applications). The enclosures however can themselves be sturdy enough to provide the necessary loading on the fuel cell stacks within. The present invention takes advantage of that to allow for use of thinner end plates and/or weaker straps which would otherwise be insufficient for use.

A hybrid bipolar plate assembly for a fuel cell includes a formed cathode half plate and a stamped metal anode half plate. The stamped metal anode half plate is nested with and affixed to the formed cathode half plate. Each of the half plates has a reactant side and a coolant side, a feed region, and a header with a plurality of header apertures. The coolant side of the formed cathode half plate has support features that can be different from and need not correspond with cathode flow channels formed on the opposite reactant side. The coolant side of the stamped metal anode half plate has lands corresponding with anode channels formed on the opposite oxidant side. The lands define a plurality of coolant channels on the coolant side of the stamped metal anode half plate and abut the coolant side of the formed cathode half plate.

A hybrid bipolar plate assembly for a fuel cell includes a formed cathode half plate and a stamped metal anode half plate. The stamped metal anode half plate is nested with and affixed to the formed cathode half plate. Each of the half plates has a reactant side and a coolant side, a feed region, and a header with a plurality of header apertures. The coolant side of the formed cathode half plate has support features that can be different from and need not correspond with cathode flow channels formed on the opposite reactant side. The coolant side of the stamped metal anode half plate has lands corresponding with anode channels formed on the opposite oxidant side. The lands define a plurality of coolant channels on the coolant side of the stamped metal anode half plate and abut the coolant side of the formed cathode half plate.

A stainless steel sheet for fuel cell separators comprises a predetermined chemical composition, wherein the stainless steel sheet has a textured structure at a surface thereof, an average interval between projected parts of the textured structure being 20 nm or more and 200 nm or less, and a ratio [Cr]/[Fe] of an atomic concentration of Cr existing in chemical form other than metal to an atomic concentration of Fe existing in chemical form other than metal at the surface of the stainless steel sheet is 2.0 or more.