A fuel cell stack comprising a plurality of fuel cells, each having an
anode flow field plate, a cathode flow field plate and a membrane
electrode assembly disposed between the flow field plates. The anode and
cathode flow field plates have primary channels and ribs separating the
primary channels. At least a portion of the anode and cathode primary
channels are disposed directly opposite one another with a membrane
exchange assembly therebetween and with at least some of the ribs on the
anode and cathode flow field plates located directly opposite one another
to sandwich the membrane exchange assembly therebetween. The flow field
plates can also have inlet distribution and outlet collection channels.
Each of these distribution and collection channels is connected to a
plurality of the primary channels, preferably located centrally, so as to
improve flow distribution of the reactants.
