Known fuel cells are designed to prevent internal leakage currents during operation. The known cells are designed so that the anode and the cathode within the same cells are insulated from one another by materials with a volume-resistivity of 10.sup.10 -10.sup.10 .OMEGA. cm and above. Examples of such fuel cells are given in the Canadian Pat. No. 867,991, in Canadian Pat. No. 1,129,946, in U.S. Pat. No. 4,048,386 and in U.S. Pat. No. 4,233,371. In the handbook by Y. Breelle and others, Principes technologie and applications de piles a combustible, Institut Francais du Petrole, Paris (1972), it is emphatically recommended on page 41 to thoroughly insulate the electrodes from one another within the fuel cell.
The known state of the art is thus strongly biased against the novel fuel cell according to the invention, in which the electrical resistance between the anode and the cathode within this fuel cell has been reduced relative to the prior art rather than, as would be obvious, to increase this electrical resistance in order to achieve a still further increased insulation between the relative anode and cathode.