Experimental approach to the weeping effect The weeping effect can be considered roughly as an electrolyte leakage through the hydrophobic film of the cathode, while the cell is working. Several explanations of this phenomenon have been given; we cite only the most common one. According to this explanation, weeping is due to isothermal distillation of the electrolyte through the pores of the electrode. When the cell is working, there is a rise in KOH concentration in the pores of the electrode on the gas side due to OH-consumption). Thus a partial-pressure gradient of water vapor is formed and this gradient causes water transfer by distillation. The water evaporates from the less concentrated KOH solution (in the electrolyte matrix) and condenses in the concentrated KOH solution at the electrode surface. This water deposition in the pores of the electrode then induces a pressure excess which expels electrolyte from the electrode. To observe the phenomenon experimentally, the droplets coming from the cathode were collected in a flask of distilled water in which a conductimetry cell was installed. Thus the decrease in resistivity of the water was indicative of the amount of KOH escaping from the electrode when the cell was working as is shown in Figure 6. We investigated a possible method for reducing the weeping effect; this consisted if humidifying the oxygen, so as to compensate for the water consumed in creating OH- ons at the cathode. The resistivity of the KOH collected at the cathode was found to
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