A fuel cell layer and methods for making a fuel cell layer comprising at
least one fuel cell in communication with first reactant plenum and
second reactant plenum, wherein one of the reactant plenums contains
oxidant and the other reactant plenum contains fuel. The fuel cell
comprises a gas barrier region formed by disposing gas barrier material
on a substrate; a second region having a first port formed on the gas
barrier; a first gas diffusion electrode having a first seal disposed
around the electrode; an electrolyte region formed by disposing
electrolyte material on the second region; a fourth region having a
second port formed on the electrolyte region; a second gas diffusion
electrode having a second seal disposed around the electrode, wherein the
second and fourth regions are in communication with the electrolyte
region, and the gas barrier region separates the first reactant plenum
from the second reactant plenum.