Patent ID: 8247133

Claim:
A fuel cell formed by stacking an electrolyte electrode assembly and a separator, said electrolyte electrode assembly including an anode, a cathode, and an electrolyte interposed between said anode and said cathode, said fuel cell further comprising: a fuel gas channel being formed on one surface of said separator for supplying a fuel gas from a center to an outer circumferential portion along a surface of said anode; an oxygen-containing gas channel being formed on the other surface of said separator for supplying an oxygen-containing gas along a surface of said cathode, said separator having a fuel gas inlet for supplying the fuel gas before consumption to said fuel gas channel, wherein said fuel gas channel comprises grooves and ridges provided alternately toward the outer circumferential portion on the surface of said anode, wherein the grooves comprise a plurality of ring shaped grooves formed around said fuel gas inlet and a single connection groove connecting adjacent ring shaped grooves, wherein said single connection grooves are arranged on a front side and a back side alternately of connecting adjacent ring shaped grooves, and wherein a groove width of adjacent grooves arranged between said ridges increases gradually toward said outer circumferential portion on the surface of said anode.