A cell stack device includes cells, a metal member containing chromium, a covering layer, and a bonding material. The cells include a first cell and the cells includes respective element portions. The covering layer covers the metal member. The bonding material is positioned between the first cell and the covering layer. The cell stack device satisfies any one of (1) The covering layer includes at least two portions having different thicknesses or different surface roughnesses at different positions. (2) A surface roughness of the covering layer is different from that of the metal member. (3) At least one element selected from the group consisting of Mn, Ti, Ca, and Al is positioned at the interface between the metal member and the covering layer, and the content ratio of the at least one element at the interface is different from that of the metal member or the covering layer.

A membrane humidifier has a housing and a membrane stack. The membrane stack includes two first stack sides aligned parallel to the assembly direction. The membrane humidifier has a sealing device with two first sealing frames, each with an inner sealing surface and an outer sealing surface. The housing has two first housing sealing surfaces. The first sealing frames are in sealing contact with the inner sealing surfaces on the first stack sides. The first sealing frames are in contact with the outer sealing surfaces on the first housing sealing surfaces. The outer sealing surfaces of the first sealing frames and the first housing sealing surfaces of the housing are each aligned at a mounting angle to the first stack sides and to the mounting direction that is not zero. In addition, an arrangement is provided which includes the membrane humidifier and the sealing device for the membrane humidifier.

A membrane humidifier has a housing and a membrane stack. The membrane stack includes two first stack sides aligned parallel to the assembly direction. The membrane humidifier has a sealing device with two first sealing frames, each with an inner sealing surface and an outer sealing surface. The housing has two first housing sealing surfaces. The first sealing frames are in sealing contact with the inner sealing surfaces on the first stack sides. The first sealing frames are in contact with the outer sealing surfaces on the first housing sealing surfaces. The outer sealing surfaces of the first sealing frames and the first housing sealing surfaces of the housing are each aligned at a mounting angle to the first stack sides and to the mounting direction that is not zero. In addition, an arrangement is provided which includes the membrane humidifier and the sealing device for the membrane humidifier.

In order to provide an electrochemically active unit for an electrochemical device including a membrane electrode assembly, at least one gas diffusion layer and a seal that is linked to at least one of the at least one gas diffusion layers, in the manufacture whereof as even as possible a construction of the penetration region in which the gas diffusion layer of the electrochemically active unit is penetrated by the sealing material of the seal over the periphery of the gas diffusion layer is achievable, the seal includes a linking region, a distribution region and a connection region that connects the linking region and the distribution region to one another, wherein the connection region has a minimum height that is less than a quarter of the maximum height of the distribution region and less than a quarter of the maximum height of the linking region.

In order to provide an electrochemically active unit for an electrochemical device including a membrane electrode assembly, at least one gas diffusion layer and a seal that is linked to at least one of the at least one gas diffusion layers, in the manufacture whereof as even as possible a construction of the penetration region in which the gas diffusion layer of the electrochemically active unit is penetrated by the sealing material of the seal over the periphery of the gas diffusion layer is achievable, the seal includes a linking region, a distribution region and a connection region that connects the linking region and the distribution region to one another, wherein the connection region has a minimum height that is less than a quarter of the maximum height of the distribution region and less than a quarter of the maximum height of the linking region.

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.

Disclosed herein are membrane-electrode-subgasket assembly and a membrane-electrode-subgasket assembly manufactured by the method. The membrane-electrode-subgasket assembly includes substrates having sizes and shapes asymmetric with each other provided on a first and second surfaces thereof.

Disclosed herein are membrane-electrode-subgasket assembly and a membrane-electrode-subgasket assembly manufactured by the method. The membrane-electrode-subgasket assembly includes substrates having sizes and shapes asymmetric with each other provided on a first and second surfaces thereof.

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.