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 fuel cell separator includes a coolant flow field formed between first and second metal separator plates. A first communication hole is formed in an outer peripheral wall of each of passage sealing beads that surround respectively an air vent passage and a coolant drain passage which are formed so as to penetrate in a separator thickness direction. A second communication hole is formed in an inner peripheral wall of each of the passage sealing beads. The first communication hole and the second communication hole are positioned to be displaced from each other in an extending direction of a first internal channel or a second internal channel.

A fuel cell separator includes a coolant flow field formed between first and second metal separator plates. A first communication hole is formed in an outer peripheral wall of each of passage sealing beads that surround respectively an air vent passage and a coolant drain passage which are formed so as to penetrate in a separator thickness direction. A second communication hole is formed in an inner peripheral wall of each of the passage sealing beads. The first communication hole and the second communication hole are positioned to be displaced from each other in an extending direction of a first internal channel or a second internal channel.

A direct alcohol fuel cell having an inner housing, and a proton exchange membrane separating an anode section from a cathode section. The anode section contains an anode collection element electrically connected to an anode catalyst that is in diffusive communication with a fuel supply. The cathode section contains a cathode collection element having one or more ventilation holes is electrically connected to a cathode catalyst. An oleophobic filter and/or an anion-exchange membrane is provided, which cathode catalyst via the one or more ventilation holes and the oleophobic filter and/or the anion-exchange membrane is in diffusive communication with a gaseous oxidant. The inner housing has a bottom and walls extending from the bottom to contain the anode section, the PEM and the cathode section, the bottom and/or the walls having holes allowing fluid communication from a fuel supply to the anode section. The fuel cell is suited for microelectronic devices.

A direct alcohol fuel cell having an inner housing, and a proton exchange membrane separating an anode section from a cathode section. The anode section contains an anode collection element electrically connected to an anode catalyst that is in diffusive communication with a fuel supply. The cathode section contains a cathode collection element having one or more ventilation holes is electrically connected to a cathode catalyst. An oleophobic filter and/or an anion-exchange membrane is provided, which cathode catalyst via the one or more ventilation holes and the oleophobic filter and/or the anion-exchange membrane is in diffusive communication with a gaseous oxidant. The inner housing has a bottom and walls extending from the bottom to contain the anode section, the PEM and the cathode section, the bottom and/or the walls having holes allowing fluid communication from a fuel supply to the anode section. The fuel cell is suited for microelectronic devices.

The present disclosure is directed towards the design of electrochemical cells for use in high pressure or high differential pressure operations. The electrochemical cells of the present disclosure have non-circular external pressure boundaries, i.e., the cells have non-circular profiles. In such cells, the internal fluid pressure during operation is balanced by the axial tensile forces developed in the bipolar plates, which prevent the external pressure boundaries of the cells from flexing or deforming. That is, the bipolar plates are configured to function as tension members during operation of the cells. To function as an effective tension member, the thickness of a particular bipolar plate is determined based on the yield strength of the material selected for fabricating the bipolar plate, the internal fluid pressure in the flow structure adjacent to the bipolar plate, and the thickness of the adjacent flow structure.

The present disclosure is directed towards the design of electrochemical cells for use in high pressure or high differential pressure operations. The electrochemical cells of the present disclosure have non-circular external pressure boundaries, i.e., the cells have non-circular profiles. In such cells, the internal fluid pressure during operation is balanced by the axial tensile forces developed in the bipolar plates, which prevent the external pressure boundaries of the cells from flexing or deforming. That is, the bipolar plates are configured to function as tension members during operation of the cells. To function as an effective tension member, the thickness of a particular bipolar plate is determined based on the yield strength of the material selected for fabricating the bipolar plate, the internal fluid pressure in the flow structure adjacent to the bipolar plate, and the thickness of the adjacent flow structure.

Improved contact between interconnect and oxygen electrode material is achieved through a contact point between an electrode or a contact layer and a coated ferritic stainless steel interconnect, where the coating on the metallic interconnect comprises Cu.

Improved contact between interconnect and oxygen electrode material is achieved through a contact point between an electrode or a contact layer and a coated ferritic stainless steel interconnect, where the coating on the metallic interconnect comprises Cu.

A bead-type separator for a fuel cell includes a reaction surface disposed at a center of the separator and for reacting a flowing reaction gas, a diffusion part disposed at both sides of the reaction surface for diffusing the reaction gas, multiple manifold through-holes disposed in regions at both ends of the separator and introducing or discharging the reaction gas, and multiple protruding inner bead seals along a periphery of the regions in which the manifold through-holes are disposed, wherein the inner bead seals comprise a first inner bead seal disposed at the periphery of the region in which the manifold through-hole configured to discharge the reaction gas is formed, and wherein the first inner bead seal includes multiple main discharge bead flow fields protruding in tunnel shapes from a diffusion part and multiple main connection bead flow fields.