Fuel cell stack

A fuel cell stack comprising a plurality of power generation units each including at least first and second electrolyte electrode assemblies, said first electrolyte electrode assembly being stacked on a first separator, a second separator being stacked on said first electrolyte electrode assembly, said second electrolyte electrode assembly being stacked on said second separator, a third separator being stacked on said second electrolyte electrode assembly, said first and second electrolyte electrode assemblies each including a pair of electrodes and an electrolyte interposed between said electrodes,

• reactant gas flow fields being formed between said first separator and said first electrolyte electrode assembly, between said first electrolyte electrode assembly and said second separator, between said second separator and said second electrolyte electrode assembly, and between said second electrolyte electrode assembly and said third separator, respectively, for flowing a predetermined reaction gas along power generation surfaces,
• a coolant flow field being formed between said power generation units,
• said fuel cell stack comprising:
• an end power generation unit adjacent to said power generation unit provided at least at one end in a direction of stacking said power generation units;
• and
• a pair of end plates, between which the plurality of power generation units and said end power generation unit are provided,
• said end power generation unit being formed by stacking a first separator of the end power generation unit on said power generation unit, a first electrolyte electrode assembly of the end power generation unit on said first separator of the end power generation unit, a second separator of the end power generation unit on said first electrolyte electrode assembly of the end power generation unit, a dummy electrolyte electrode assembly on said second separator of the end power generation unit, and a third separator of the end power generation unit on said dummy electrolyte electrode assembly, respectively, wherein:
• the first electrolyte electrode assembly of the end power generation unit has the same structure as the first electrolyte electrode assemblies of the power generation units,
• said dummy electrolyte assembly is positioned closer to one of the end plates than the first electrolyte electrode assembly of the end power generation unit at the one end, and said dummy electrolyte electrode assembly has an electrically conductive plate corresponding to said electrolyte, and
• said coolant flow field is sandwiched between the third separator of a power generation unit and the first separator of an adjacent power generation unit.