A fuel cell flow field plate includes an aluminum substrate plate having a first side and a second side wherein the first side of the aluminum substrate plate defines a plurality of channels for transporting a first fuel cell reactant gas. The flow field plate also includes a first metal interlayer deposited on the first side of the aluminum substrate plate, a second metal interlayer deposited on the second side of the aluminum substrate plate, a first amorphous carbon layer deposited on the first metal interlayer, and a second amorphous carbon layer deposited on the second metal interlayer. The first amorphous carbon layer and second amorphous carbon layer each independently have a density greater than or equal to 1.2 g/cc.

The invention relates to a bipolar plate (1) for a fuel cell, comprising a bipolar plate substrate (2) composed of stainless steel and comprising a coating (3), which is applied to the bipolar plate substrate (2), for increasing the corrosion resistance of the bipolar plate (1). According to the invention, the coating (3) is of single- or multi-layer design and has at least one layer (4) composed of a metal matrix (5) with non-passivating dispersoid particles (6) incorporated therein. The invention further relates to a fuel cell having at least one bipolar plate (1) according to the invention.

The invention relates to a bipolar plate (1) for a fuel cell, comprising a bipolar plate substrate (2) composed of stainless steel and comprising a coating (3), which is applied to the bipolar plate substrate (2), for increasing the corrosion resistance of the bipolar plate (1). According to the invention, the coating (3) is of single- or multi-layer design and has at least one layer (4) composed of a metal matrix (5) with non-passivating dispersoid particles (6) incorporated therein. The invention further relates to a fuel cell having at least one bipolar plate (1) according to the invention.

A layer system for coating a metal substrate in order to form a flow field plate includes at least one cover layer made of metal oxide; at least one intermediate layer, which supports the cover layer; and a lower layer, which supports the intermediate layer(s). The cover layer is formed of indium tin oxide; wherein the indium tin oxide is optionally doped with at least one element from the group comprising carbon, nitrogen, boron, fluorine, hydrogen, silicon, titanium, tin and zirconium. At least one intermediate layer is formed of titanium nitride and/or titanium carbide and/or titanium carbonitride and/or titanium niobium nitride and/or titanium niobium carbide and/or titanium niobium carbonitride and/or chromium nitride and/or chromium carbide and/or chromium carbonitride. The lower layer is formed of titanium or a titanium-niobium alloy or chromium.

A layer system for coating a metal substrate in order to form a flow field plate includes at least one cover layer made of metal oxide; at least one intermediate layer, which supports the cover layer; and a lower layer, which supports the intermediate layer(s). The cover layer is formed of indium tin oxide; wherein the indium tin oxide is optionally doped with at least one element from the group comprising carbon, nitrogen, boron, fluorine, hydrogen, silicon, titanium, tin and zirconium. At least one intermediate layer is formed of titanium nitride and/or titanium carbide and/or titanium carbonitride and/or titanium niobium nitride and/or titanium niobium carbide and/or titanium niobium carbonitride and/or chromium nitride and/or chromium carbide and/or chromium carbonitride. The lower layer is formed of titanium or a titanium-niobium alloy or chromium.

An alloy member includes a base member that includes a recess in a surface of the base member and is constituted by an alloy material containing chromium, an anchor portion is disposed in the recess and contains an oxide containing manganese and a covering layer is connected to the anchor portion and contains a low-equilibrium oxygen pressure element whose equilibrium oxygen pressure is lower than that of chromium.

An alloy member includes a base member that includes a recess in a surface of the base member and is constituted by an alloy material containing chromium, an anchor portion is disposed in the recess and contains an oxide containing manganese and a covering layer is connected to the anchor portion and contains a low-equilibrium oxygen pressure element whose equilibrium oxygen pressure is lower than that of chromium.

Fuel cell alloy bipolar plates. The alloys may be used as a coating or bulk material. The alloys and metallic glasses may be particularly suitable for proton-exchange membrane fuel cells because of they may exhibit reduced weights and/or better corrosion resistance. The alloys may include any of the following Al.sub.xCu.sub.yTi.sub.z, Al.sub.xFe.sub.yNi.sub.z, Al.sub.xMn.sub.yNi.sub.z, Al.sub.xNi.sub.yTi.sub.z, Cu.sub.xFe.sub.yTi.sub.z, Cu.sub.xNi.sub.yTi.sub.z, Al.sub.xFe.sub.ySi.sub.z, Al.sub.xMn.sub.ySi.sub.z, Al.sub.xNi.sub.ySi.sub.z, Ni.sub.xSi.sub.yTi.sub.z, and C.sub.xFe.sub.ySi.sub.z. The alloys or metallic glass may be doped with various dopants to improve glass forming ability, mechanical strength, ductility, electrical or thermal conductivities, hydrophobicity, and/or corrosion resistance.

Fuel cell alloy bipolar plates. The alloys may be used as a coating or bulk material. The alloys and metallic glasses may be particularly suitable for proton-exchange membrane fuel cells because of they may exhibit reduced weights and/or better corrosion resistance. The alloys may include any of the following Al.sub.xCu.sub.yTi.sub.z, Al.sub.xFe.sub.yNi.sub.z, Al.sub.xMn.sub.yNi.sub.z, Al.sub.xNi.sub.yTi.sub.z, Cu.sub.xFe.sub.yTi.sub.z, Cu.sub.xNi.sub.yTi.sub.z, Al.sub.xFe.sub.ySi.sub.z, Al.sub.xMn.sub.ySi.sub.z, Al.sub.xNi.sub.ySi.sub.z, Ni.sub.xSi.sub.yTi.sub.z, and C.sub.xFe.sub.ySi.sub.z. The alloys or metallic glass may be doped with various dopants to improve glass forming ability, mechanical strength, ductility, electrical or thermal conductivities, hydrophobicity, and/or corrosion resistance.

An alloy member includes a base member that includes a plurality of recesses in a surface and is constituted by an alloy material containing chromium, a plurality of embedded portions that are respectively disposed in the plurality of recesses, and a coating layer that covers the base member and is connected to the plurality of embedded portions. An average value of actual lengths of line segments of the plurality of embedded portions is longer than an average value of straight lengths of straight lines of the plurality of embedded portions in a cross-section of the base member along a thickness direction of the base member. The average value of the actual lengths is 1.10 times or more the average value of the lengths of the straight lines.