Brennstoffelement

1,140,829. Fuel cell gas manifold system. UNITED AIRCRAFT CORP. 13 Oct., 1967 [7 Nov., 1966], No. 46711/67. Heading H1B. In a fuel cell containing an aqueous electrolyte disposed between a fuel electrode and an oxident electrode, in which a fuel gas is supplied to the fuel electrode and oxidant gas to the oxidant electrode, at least one of the gases is distributed over the surface of its electrode by passage through a chamber in which the inlet and exit ports are closely adjacent to each other and to the electrode surface. In Fig. 1 gas enters chamber 24 by inlet port 26 and flows over the electrode surface round the baffle 25, as shown by arrow 27, to leave at outlet port 28. Any excessive drying near port 26 can thus easily be made good by diffusion of electrolyte from the comparatively " wet " region near port 28. Suitable gases are hydrogen and dry air; suitable electrodes contain Pt or Pd catalyst with PTFE binder on a nickel mesh; the electrolyte may be 30% aqueous KOH (or NaOH, LiOH, RbOH or CsOH); the electrolyte matrix may be of asbestos and be 0À1-0À2 inch thick.