Patent ID: 8323853

Claim:
A fuel cell stack formed by stacking a plurality of fuel cells formed by stacking electrolyte electrode assemblies and separators, said electrolyte electrode assemblies each including an anode, a cathode, and an electrolyte interposed between said anode and said cathode, said separators each comprising: sandwiching sections for sandwiching said electrolyte electrode assemblies, at least a fuel gas inlet for supplying a fuel gas along an electrode surface of said anode or an oxygen-containing gas inlet for supplying an oxygen-containing gas along an electrode surface of said cathode being formed in each of said sandwiching sections; first bridges connected to said sandwiching sections, and each having a first reactant gas supply channel for supplying the fuel gas to said fuel gas inlet or supplying the oxygen-containing gas to said oxygen-containing gas inlet; a first reactant gas supply unit connected to said first bridges, a first reactant gas supply passage extending through said first reactant gas supply unit in a stacking direction for supplying the fuel gas or the oxygen-containing gas to said first reactant gas supply channel; second bridges connected to said sandwiching sections, and each having a second reactant gas supply channel for supplying the fuel gas to said fuel gas inlet or supplying the oxygen-containing gas to said oxygen-containing gas inlet; a case unit connected to said second bridges, said case unit containing said electrolyte electrode assemblies; a second reactant gas supply unit provided in said case unit, a second reactant gas supply passage extending through said second reactant gas supply unit in the stacking direction for supplying the oxygen-containing gas or the fuel gas to said second reactant gas supply channel; a first load applying mechanism provided at said first reactant gas supply unit; a second load applying mechanism provided at said second reactant gas supply unit; and a third load applying mechanism provided at said sandwiching sections, wherein a first surface pressure in the stacking direction is generated by applying a first load to said first reactant gas supply unit, a second surface pressure in the stacking direction is generated by applying a second load to said second reactant gas supply unit, and a third surface pressure in the stacking direction is generated by applying a third load to said sandwiching sections, the first surface pressure being larger than the second surface pressure, and the second surface pressure being larger than the third surface pressure.