Patent ID: 8062807

Claim:
A fuel cell formed by stacking an electrolyte electrode assembly and separators alternately, said electrolyte electrode assembly including an anode, a cathode, and an electrolyte interposed between said anode and said cathode, said fuel cell comprising an oxygen-containing gas flow field for supplying an oxygen-containing gas to said cathode being formed on one surface of each separator, a fuel gas flow field for supplying a fuel gas to said anode being formed on the other surface of each separator, and a fuel gas supply passage for supplying the fuel gas before consumption and extending through said fuel cell in the stacking direction, wherein said separator has a fuel gas channel connected to said fuel gas supply passage, between said fuel gas flow field and said oxygen-containing gas flow field; said fuel gas channel is divided into first and second fuel gas channel units by a partition; said first fuel gas channel unit has a fuel gas inlet for supplying the fuel gas before consumption from said fuel gas supply passage to said fuel gas flow field; said second fuel gas channel unit has an exhaust fuel gas diverging hole for diverging at least some of an exhaust fuel gas which has been used in the reaction at said anode from said fuel gas flow field; said second fuel gas channel unit is connected to said fuel gas supply passage through an exhaust fuel gas diverging passage said separator includes first and second plates which are stacked together; said first and second plates have first and second protrusions protruding in different directions; said first protrusion comprises a plurality of protrusions which contact an inner region of said anode to form said fuel gas flow field and a substantially ring shaped protrusion provided around the plurality of protrusions to contact an outer region of said anode; said first fuel gas channel unit is formed by the back surfaces of said plurality of protrusions and said partition; and said second fuel gas channel unit is formed by the back surface of said substantially ring shaped protrusion and said partition.