US Patent 8173320 Fuel cell stack and method for making the same

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.