A power generation cell includes a membrane electrode assembly and first
and second metal separators sandwiching the membrane electrode assembly.
The first metal separator is a thin metal plate. A first seal member is
formed integrally around the outer end of the first metal separator. A
portion defining an orifice is provided in an outer marginal region of
the first metal separator. The thickness H1 of the first seal member in
the area covering the portion defining the orifice is larger than the
thickness of the H2 of the first seal member in the area covering other
portions.