Abstract: A liquid thermosetting sealing agent for a polymer electrode membrane fuel cell having separators and a membrane electrode assembly laminated, whose the viscosity at the application is from 1,000 to 9,000 Pa·S, can be used to prepare a highly durable seal for a polymer electrode membrane fuel cell, to produce a single cell having a highly durable seal and to recover the fuel cell whose seal becomes abnormality.

Abstract: A method for fabricating a seal-integrated separator for a fuel cell is presented, with which seals can be accurately positioned and the assembling time for the fuel cells may be greatly reduced. The method comprises the steps of: providing an upper mold having a groove positioned corresponding to second and fourth seals disposed on one side of a separator body, and a lower mold having a groove positioned corresponding to first and third seals disposed on the other side of the separator body; holding the separator body between the upper mold and the lower mold; and injecting melted seal material to form the seals into each of the grooves in the upper mold and the lower mold through separate gates respectively formed in the upper and lower molds. Through this method, a seal-integrated separator having the first to fourth seals which are integrated on both sides of the separator body is fabricated.

Abstract: A sealing structure in a fuel cell comprises a pair of separators including gas passages and a membrane electrode assembly held by the pair of separators and having a polymerized electrolytic membrane and a electrode layer so as to form a fuel cell. The sealing structure seals a sealing portion between the pair of the separators and the polymerized electrolytic membrane. A sealing groove is provided to the sealing portion of one of the separators, and a first seal has a thickness greater than the depth of the sealing groove and a portion which is gradually narrowed toward an end thereof. A protrusion is provided to the sealing portion of the other separator, and a second seal having a constant width is provided to the front surface of the protrusion. The polymerized electrolytic membrane is held by the first seal and the second seal.

Abstract: A seal in a fuel cell for sealing a membrane electrode assembly comprises a pair of catalytic electrode layers, a polymerized electrolytic membrane held between the catalytic layers, and a gas diffusion layer layered on the outer surface of the catalytic electrode layer. The seal is integrally formed with the polymerized electrolytic membrane. The height thereof is greater than that of the gas diffusion layer. The difference between the heights of the polymerized electrolytic membrane and the gas diffusion layer is constant.

Abstract: A method for fabricating a seal-integrated separator for a fuel cell is presented, with which seals can be accurately positioned and the assembling time for the fuel cells may be greatly reduced. The method comprises the steps of: providing an upper mold having a groove positioned corresponding to second and fourth seals disposed on one side of a separator body, and a lower mold having a groove positioned corresponding to first and third seals disposed on the other side of the separator body; holding the separator body between the upper mold and the lower mold; and injecting melted seal material to form the seals into each of the grooves in the upper mold and the lower mold through separate gates respectively formed in the upper and lower molds. Through this method, a seal-integrated separator having the first to fourth seals which are integrated on both sides of the separator body is fabricated.

Abstract: A liquid thermosetting sealing agent for a polymer electrode membrane fuel cell having separators and a membrane electrode assembly laminated, whose the viscosity at the application is from 1,000 to 9,000 Pa.S, can be used to prepare a highly durable seal for a polymer electrode membrane fuel cell, to produce a single cell having a highly durable seal and to recover the fuel cell whose seal becomes abnormality.

Abstract: A liquid thermosetting sealing agent for a polymer electrode membrane fuel cell having separators and a membrane electrode assembly laminated, whose the viscosity at the application is from 1,000 to 9,000 Pa.S, can be used to prepare a highly durable seal for a polymer electrode membrane fuel cell, to produce a single cell having a highly durable seal and to recover the fuel cell whose seal becomes abnormality.

Abstract: A sealing structure in a fuel cell comprises a pair of separators including gas passages and a membrane electrode assembly held by the pair of separators and having a polymerized electrolytic membrane and a electrode layer so as to form a fuel cell. The sealing structure seals a sealing portion between the pair of the separators and the polymerized electrolytic membrane. A sealing groove is provided to the sealing portion of one of the separators, and a first seal has a thickness greater than the depth of the sealing groove and a portion which is gradually narrowed toward an end thereof. A protrusion is provided to the sealing portion of the other separator, and a second seal having a constant width is provided to the front surface of the protrusion. The polymerized electrolytic membrane is held by the first seal and the second seal.

Abstract: A seal in a fuel cell for sealing a membrane electrode assembly comprises a pair of catalytic electrode layers, a polymerized electrolytic membrane held between the catalytic layers, and a gas diffusion layer layered on the outer surface of the catalytic electrode layer. The seal is integrally formed with the polymerized electrolytic membrane. The height thereof is greater than that of the gas diffusion layer. The difference between the heights of the polymerized electrolytic membrane and the gas diffusion layer is constant.