Brennstoffzelle

1,205,004. Fuel cell. UNITED AIRCRAFT CORP. 14 Jan., 1969 [12 Feb., 1968], No. 2098/69. Heading H1B. In a fuel cell, of the H 2 /O 2 -KOH type, employing permeable electrodes 10, 12 and having a concentration gradient of OH- ions, carbon containing substances are removed from the alkaline electrolyte 14a by promoting the generation of gaseous carbon-dioxide from CO 3 2- and HCO 3 - by disposing a diffusion barrier 40, of for example porous nickel or asbestos, adjacent the anode 10 to provide a mild impedance to the imigration of ions toward and away from anode 10 which allows a OH- ion concentration gradient to exist and permits a lower concentration of OH- at the liquid interface 30 in the anode. Thus the pH in the liquid side of the interface can be lowered to 8 or 9 thus promoting the reaction The diffusion barrier also slows the migration of CO 3 2- and HCO 8 - ions away from anode 10 thus promoting the reaction The diffusion barrier 40 also impedes the diffusion of CO 2 into the bulk of electrolyte 14a, thus allowing the build-up of sufficient pressure of the molecules to diffuse through the anode and be carried away in the gaseous effluent through duct 22.