Abstract: A cell of a fuel cell includes a membrane electrode assembly, and metal first and second separators which sandwich the membrane electrode assembly to form gas flow paths disposed on each side of the membrane electrode assembly. A back surface of the first separator and a back surface of the second separator, the first separator and the second separator being included in adjacent cells, are in contact with each other, thereby forming a temperature-control medium flow path between the first separator and the second separator. In the first separator and the second separator, corrosion-resistant coating layers are provided only on reaction-side surfaces of the first separator and the second separator, the reaction-side surfaces facing the membrane electrode assembly, and portions where the back surface of the first separator is in contact with the back surface of the second separator are joined by welded portions.

Abstract: A fuel cell stack includes a membrane electrode assembly including an electrolyte membrane and electrode catalyst layers sandwiching the electrolyte membrane; metal separators that define gas channels, the metal separators being respectively disposed at both surfaces of the membrane electrode assembly; a current collector from which electromotive force is derived, the current collector being in contact with at least one of the metal separators; and joining parts that join the metal separator to the current collector at portions where the metal separator contacts the current collector.

Abstract: A cell of a fuel cell includes a membrane electrode assembly, and metal first and second separators which sandwich the membrane electrode assembly to form gas flow paths disposed on each side of the membrane electrode assembly. A back surface of the first separator and a back surface of the second separator, the first separator and the second separator being included in adjacent cells, are in contact with each other, thereby forming a temperature-control medium flow path between the first separator and the second separator. In the first separator and the second separator, corrosion-resistant coating layers are provided only on reaction-side surfaces of the first separator and the second separator, the reaction-side surfaces facing the membrane electrode assembly, and portions where the back surface of the first separator is in contact with the back surface of the second separator are joined by welded portions.

Abstract: A fuel cell stack includes a membrane electrode assembly including an electrolyte membrane and electrode catalyst layers sandwiching the electrolyte membrane; metal separators that define gas channels, the metal separators being respectively disposed at both surfaces of the membrane electrode assembly; a current collector from which electromotive force is derived, the current collector being in contact with at least one of the metal separators; and joining parts that join the metal separator to the current collector at portions where the metal separator contacts the current collector.