Abstract: A fuel cell electrode having a catalyst layer comprising electroconductive particles carrying a catalytically active component and a binder on a water-repellent baked plate comprising a carbon paper comprising carbon fiber and an organic binder and polytetrafluoroethylene infiltrated into voids of said carbon paper, characterized in that the carbon fiber of said baked plate has at least 20 cutting edges per square millimeter, and said polytetrafluoroethylene is infiltrated into at least one of said cutting edges to render the plate flexible.

Abstract: In a fuel cell having a fuel electrode, an oxidant electrode, and an electrolyte which is located between both the electrodes, a methanol concentration control device is disposed, at a pipe which supplies the fuel to the fuel cell for controlling the amount of the methanol in the pipe by detecting the open-circuit voltage of the unit cell or the open-circuit potential of the oxidant cell at the methanol concentration control device.

Abstract: In a fuel cell comprising a pair of counterposed gas-diffusible electrodes, an electrolyte-retaining, porous matrix provided between and in contact with the electrodes, a fuel chamber for feeding a gaseous fuel to the anode of the pair of the electrodes and an oxidizing agent chamber for feeding a gaseous oxidizing agent to the cathode of the pair of the electrodes, the cell performance is remarkably prevented from lowering by making the electrolyte saturated absorption amount of the cathode smaller than that of the anode, thereby preventing migration of the electrolyte in the electrolyte-retaining matrix.