A bipolar flat element comprising a coating that contains expanded graphite and a binder, the coating being applied to at least one of the two primary surfaces of a flat, electrically conductive element.

The invention relates to an electricity generating electrochemical device of the solid-oxide fuel-cell stack type. The device includes a planar assembly having at least one electrochemical cell comprised between first and second gas diffusing plates made of ceramic of expansion coefficient between 8×10.sup.−6 K.sup.−1 and 14×10.sup.−6K.sup.−1 and drilled with equidistant holes. First and second current conductive metal grids each are connected to a conductive wire allowing current to flow out of the device. The grilles are placed on either side of the at least one electrochemical cell between this cell and each of the first and second gas diffusing plates. A clamping device mechanically holds the planar assembly together.

The invention relates to an electricity generating electrochemical device of the solid-oxide fuel-cell stack type. The device includes a planar assembly having at least one electrochemical cell comprised between first and second gas diffusing plates made of ceramic of expansion coefficient between 8×10.sup.−6 K.sup.−1 and 14×10.sup.−6K.sup.−1 and drilled with equidistant holes. First and second current conductive metal grids each are connected to a conductive wire allowing current to flow out of the device. The grilles are placed on either side of the at least one electrochemical cell between this cell and each of the first and second gas diffusing plates. A clamping device mechanically holds the planar assembly together.

There is provided a fuel cell comprising a cell stacked body and a case configured to surround at least stacked body side faces of the cell stacked body. The case comprises a first case configured to include a first case side wall and a pair of first opposed side walls that are arranged to rise from a circumference of the first case side wall such as to have a draft angle; and a second case configured to include a second case side wall and a pair of second opposed side walls that are arranged to rise from a circumference of the second case side wall such as to have a draft angle. A first edge of each of the first opposed side walls is joined with a second edge of each of the second opposed side walls. This configuration suppresses size expansion of the fuel cell.

There is provided a fuel cell comprising a cell stacked body and a case configured to surround at least stacked body side faces of the cell stacked body. The case comprises a first case configured to include a first case side wall and a pair of first opposed side walls that are arranged to rise from a circumference of the first case side wall such as to have a draft angle; and a second case configured to include a second case side wall and a pair of second opposed side walls that are arranged to rise from a circumference of the second case side wall such as to have a draft angle. A first edge of each of the first opposed side walls is joined with a second edge of each of the second opposed side walls. This configuration suppresses size expansion of the fuel cell.

A gas permeable or breathable electrode and method of manufacture thereof. In one example there is an electrolytic cell having an electrode comprising a porous material, wherein gas produced at the electrode diffuses out of the cell via the porous material. In operation the gas is produced at the at least one electrode without substantial bubble formation. In another example there is an electrode having a porous conducting material with a hydrophobic layer or coating applied to a side of the porous conducting material. A catalyst may be applied to another side. The gas permeable or breathable electrode can be used in an electrolytic cell, electrochemical cell, battery and/or fuel cell. Gas produced at the electrode diffuses out of a cell via at least part of the electrode, separating the gas from the reaction at the electrode.

A fuel cell includes: a membrane electrode assembly including an electrolyte membrane, catalyst layers stacked on both sides of the electrolyte membrane, and two or more porous bodies having different moduli of elasticity and provided on a surface of one of the catalyst layers; a separator defining a gas flow passage between the separator and the membrane electrode assembly; and a frame body surrounding an outer periphery of the electrolyte membrane. A porous body adjacent to the separator out of the two or more porous bodies includes an outer edge portion including an outer extending portion extending to overlap with the frame body. An elastic body is provided between the outer extending portion and the frame body.

A fuel cell includes: a membrane electrode assembly including an electrolyte membrane, catalyst layers stacked on both sides of the electrolyte membrane, and two or more porous bodies having different moduli of elasticity and provided on a surface of one of the catalyst layers; a separator defining a gas flow passage between the separator and the membrane electrode assembly; and a frame body surrounding an outer periphery of the electrolyte membrane. A porous body adjacent to the separator out of the two or more porous bodies includes an outer edge portion including an outer extending portion extending to overlap with the frame body. An elastic body is provided between the outer extending portion and the frame body.

A single cell C includes a membrane electrode assembly M in which an electrolyte membrane 1 is interposed between a pair of electrode layers 2, 3, and a pair of separators 4 that form gas channels C between the pair of separators 4 and the membrane electrode assembly M, wherein the electrode layers 2, 3 include first gas diffusion layers 2B, 3B of a porous material disposed at the side facing the electrolyte membrane 1 and second gas diffusion layers 2C, 3C that are composed of a metal porous body having arrayed many holes K, and a part of the first gas diffusion layers 2B, 3B penetrates the holes K of the second gas diffusion layers 2C, 3C to form protrusions T. Accordingly, the surface of the electrode layers 2, 3 has a fine uneven structure. As a result, an improvement in liquid water discharging function and an improvement in power generating function were achieved at the same time.

A single cell C includes a membrane electrode assembly M in which an electrolyte membrane 1 is interposed between a pair of electrode layers 2, 3, and a pair of separators 4 that form gas channels C between the pair of separators 4 and the membrane electrode assembly M, wherein the electrode layers 2, 3 include first gas diffusion layers 2B, 3B of a porous material disposed at the side facing the electrolyte membrane 1 and second gas diffusion layers 2C, 3C that are composed of a metal porous body having arrayed many holes K, and a part of the first gas diffusion layers 2B, 3B penetrates the holes K of the second gas diffusion layers 2C, 3C to form protrusions T. Accordingly, the surface of the electrode layers 2, 3 has a fine uneven structure. As a result, an improvement in liquid water discharging function and an improvement in power generating function were achieved at the same time.