Disclosed are a separator for fuel cells capable of minimizing the volume of a system and the use of sealants, and a stack for fuel cells, more particularly, a stack for solid oxide fuel cells, including the same. Specifically, by adding a metal sheet having a specific shape, position and size to the separator, the stress applied to the sealant can be uniformized, and thus the oxidizing agent and fuel can be separated and electrically isolated using only a piece of sealant. Therefore, the stack for fuel cells is characterized in that there is no variation in temperature, reactant concentration, power, or the like between respective unit cells, so delamination and microcracks do not occur, the volume is minimized, and the power density per unit volume is very high.

Methods and systems are provided for manufacturing a bipolar plate for a redox flow battery. In one example, the bipolar plate is fabricated by a roll-to-roll process. The bipolar plate includes a non-conductive substrate that is coupled to a negative electrode on a first surface and coupled to a positive electrode on a second surface, the first surface opposite of the second surface.

A gas channel forming plate is arranged between a membrane electrode assembly and a flat separator base. The gas channel forming plate includes gas channels arranged on a surface that faces the membrane electrode assembly, water channels each formed on the back side of the protrusion between an adjacent pair of the gas channels, communication passages that connect the gas channels and the water channels to each other, and guide portions formed by causing an inner wall surface of a gas channel to protrude inward in the gas channel. The guide portions are formed such that the upstream edge of each communication passage is arranged in a range in which, in the velocity vector of the gas flowing in the gas channel, the directional component directed from the side corresponding to the membrane electrode assembly toward the flat separator base has a positive value.

A process (30) for producing a distributor plate (1) for an electrochemical system, wherein the distributor plate (1) has at least one metal foil (2) having a first surface (3) and a second surface (4) and the process (30) has the following process steps: a) pretreatment (31) of the metal foil (2); b) mask formation (32) at least on the first surface (3) of the pretreated metal foil (2); c) structure formation (33) at least on the first surface (3) of the metal foil (2) provided with the mask (10), as a result of which a first fluid distributor structure (5) is formed; d) mask removal (36).

A fuel cell includes a power-generation channel provided on a surface of a cathode-side separator which faces a MEA and a cooling channel provided on a surface of the cathode-side separator opposite to the MEA. Air flows through the power-generation channel and the cooling channel. The cooling channel is separated from the power-generation channel by a side wall. The cross-sectional area of the power-generation channel on the air outlet side is smaller than that of the power-generation channel at a position upstream of the air outlet side, and the cross-sectional area of the cooling channel on the air outlet side is larger than that of the cooling channel at a position upstream of the air outlet side. A through-hole is provided in a side wall that separates the power-generation channel from the cooling channel.

A fuel cell is provided with a power generation unit; the power generation unit is provided with a first metal separator, a first electrolyte membrane/electrode structure, a second metal separator, a second electrolyte membrane/electrode structure, and a third metal separator. The first electrolyte membrane/electrode structure is provided with a first resin frame member at the outer periphery, and the first resin frame member is provided with an inlet buffer section positioned outside a power generation region and coupled to a first oxidant gas flow path, and a protruding section, which is one part of an inlet coupling flow path coupling together the inlet buffer section and an oxidant gas inlet communication hole.

A fuel cell is provided with a power generation unit; the power generation unit is provided with a first metal separator, a first electrolyte membrane/electrode structure, a second metal separator, a second electrolyte membrane/electrode structure, and a third metal separator. The first electrolyte membrane/electrode structure is provided with a first resin frame member at the outer periphery, and the first resin frame member is provided with an inlet buffer section positioned outside a power generation region and coupled to a first oxidant gas flow path, and a protruding section, which is one part of an inlet coupling flow path coupling together the inlet buffer section and an oxidant gas inlet communication hole.

An intermediate material of a thermoplastic prepreg for a fuel cell separation plate comprises a hydrophobic thermoplastic resin film and a fiber base. The hydrophobic thermoplastic resin film has a degree of crystallization of 1 to 20%, a thickness of 3 to 50 μm, and (iii) a content of an electroconductive material of 1 to 20 wt. %. The film is laminated on at least one surface of the fiber base. The thermoplastic prepreg for a fuel cell separation plate is manufactured by pressurizing the thermoplastic prepreg intermediate material at a temperature higher than the melting point of the hydrophobic thermoplastic resin film. A fuel cell separation membrane manufactured using the thermoplastic prepreg intermediate material and thermoplastic prepreg is thin and light-weight, and have a good durability.

A fuel cell separator in which the adhesion of a conductive coating formed on the surface of the fuel cell separator is further improved. The fuel cell separator (20) includes a metal substrate (24) molded from titanium, and a conductive coating (30) that exhibits conductivity and is formed on the surface of the metal substrate (24), wherein the conductive coating (30) contains conductive particles, and the average particle size of the conductive particles is not less than 1 nm and not more than 100 nm. The average particle size of the conductive particles is preferably not less than 1 nm and not more than 10 nm, and more preferably not less than 1 nm and not more than 5 nm.

A fuel cell separator in which the adhesion of a conductive coating formed on the surface of the fuel cell separator is further improved. The fuel cell separator (20) includes a metal substrate (24) molded from titanium, and a conductive coating (30) that exhibits conductivity and is formed on the surface of the metal substrate (24), wherein the conductive coating (30) contains conductive particles, and the average particle size of the conductive particles is not less than 1 nm and not more than 100 nm. The average particle size of the conductive particles is preferably not less than 1 nm and not more than 10 nm, and more preferably not less than 1 nm and not more than 5 nm.