Separator for fuel cells and method for producing same

A fuel cell separator, sandwiching a membrane electrode assembly including electrodes and an electrolyte membrane interposed between the electrodes, an outer end of the fuel cell separator being formed integrally with a seal member formed of an elastic material, and a fluid passage being formed in a surface of the fuel cell separator for allowing at least a fuel gas, an oxygen-containing gas, or a coolant as fluid to flow in a stacking direction in which the fuel cell separator and the membrane electrode assembly are stacked together,

• wherein a resin member is provided at an outer end of the fuel cell separator, outside the fluid passage, and over an entire perimeter of the fuel cell separator;
• wherein the seal member covering part of the resin member is provided on both surfaces of the fuel cell separator;
• wherein the seal member includes a ridge seal protruding farther than the resin member in a thickness direction of the fuel cell separator;
• wherein the seal member is arranged on an inner side of the resin member;
• wherein the fuel cell separator includes a gas flow field facing an electrode of the electrodes to allow the fluid to flow along the electrode;
• wherein the ridge seal is disposed between the gas flow field and the inner side of the resin member and separates the inner side of the resin member from the gas flow field;
• wherein resin flow sections for forming the resin member are provided at a plurality of positions of the resin member;
• and
• an expansion protruding outward in a direction parallel to a surface of the separator is provided between the adjacent resin flow sections.

A method of producing a fuel cell separator, sandwiching a membrane electrode assembly including electrodes and an electrolyte membrane interposed between the electrodes, an outer end of the fuel cell separator being formed integrally with a seal member formed of an elastic material, and a fluid passage being formed in a surface of the fuel cell separator for allowing at least a fuel gas, an oxygen-containing gas, or a coolant as fluid to flow in a stacking direction in which the fuel cell separator and the membrane electrode assembly are stacked together,

• the method comprising the steps of:
• providing a resin member at an outer end of the fuel cell separator, outside the fluid passage, and over an entire perimeter of the fuel cell separator;
• and
• supplying a melted seal member in a state where the resin member is held between a pair of molds to form the seal member covering part of the resin member on both surfaces of the fuel cell separator,
• wherein the seal member includes a ridge seal protruding farther than the resin member in a thickness direction of the fuel cell separator;
• wherein the seal member is arranged on an inner side of the resin member;
• wherein the fuel cell separator includes a gas flow field facing an electrode of the electrodes to allow the fluid to flow along the electrode;
• and
• wherein the ridge seal is disposed between the gas flow field and the inner side of the resin member and separates the inner side of the resin member from the gas flow field.