Abstract: A hybrid internal/external manifolded fuel cell stack comprising a plurality of fuel cell units, each of which comprises an anode and a cathode and an electrolyte in contact on one side with an electrolyte facing face of the anode and in contact on the opposite side with an electrolyte facing face of the cathode. A separator plate separates each of the fuel cell units between an anode and cathode forming an anode chamber between the anode facing face of the separator plate and the anode and forming a cathode chamber between the opposite cathode facing face of the separator plate and the cathode of an adjacent fuel cell unit. The anode chamber is in gas communication with a fuel gas supply and outlet provided through internal manifolds whereas the cathode chamber is in gas communication with an oxidant gas supply and outlet provided through external manifolds.

Abstract: Corrosion in manifolds and ducts in phosphoric acid fuel cells can be reduced by electroplating a chromium-fluorocarbon polymer composite coating onto the exposed metal surfaces. The chromium-fluorocarbon coating displays superior corrosion protection and improved adhesion after being subjected to a plurality of heating and cooling cycles. The improved corrosion protection enhances fuel cell operating reliability and allows the use of less expensive materials in the construction of the manifolds and ducts.

Abstract: Fuel cell electrodes of uniform quality are made on a continuous basis using screen printing. A wet floc is first made by floccing a co-suspension of carbon and hydrophobic polymer. The floc is dried, reduced to a fine powder, and re-suspended in an inking vehicle. The ink is then screen printed onto a porous substrate and the inking vehicle is removed such as by heating. The layer is compacted, sintered, and then catalyzed such as with platinum.

Abstract: A method for making an electrochemical cell electrode involves depositing a layer of mechanically blended dry catalyzed carbon powder and dry hydrophobic polymer powder on the surface of a substrate by dispersing the mixture of powders as a cloud in a chamber over the substrate and pulling the powder onto the substrate by drawing a vacuum under the substrate. The method is particularly adapted to the high speed manufacture of electrodes.