(EP811254-A1)      A fuel cell (17) has an anode (18) and cathode (32)positioned on opposite sides of an electrolyte (28). Both the anode (18) and the cathode (32) have a catalyst layer (24,34) on the surface facing the electrolyte (28) except in their edge regions (27). An ion impermeable layer (40) is positioned between the anode edge region and the cathode edge region (27).    USE -   A stack (2) of the fuel cells (17) is used to produce electricity. The ion impermeable layer (40) prevents reactant ions or molecules from reaching localised high potential areas of the non-catalysed parts (25,27) of the electrodes (18,32) and corroding the carbon of the electrodes.    (US5837395-A)      A fuel cell (17) has an anode (18) and cathode (32)positioned on opposite sides of an electrolyte (28). Both the anode (18) and the cathode (32) have a catalyst layer (24,34) on the surface facing the electrolyte (28) except in their edge regions (27). An ion impermeable layer (40) is positioned between the anode edge region and the cathode edge region (27).    USE -   A stack (2) of the fuel cells (17) is used to produce electricity. The ion impermeable layer (40) prevents reactant ions or molecules from reaching localised high potential areas of the non-catalysed parts (25,27) of the electrodes (18,32) and corroding the carbon of the electrodes.    (EP811254-B1)      A fuel cell (17) has an anode (18) and cathode (32)positioned on opposite sides of an electrolyte (28). Both the anode (18) and the cathode (32) have a catalyst layer (24,34) on the surface facing the electrolyte (28) except in their edge regions (27). An ion impermeable layer (40) is positioned between the anode edge region and the cathode edge region (27).    USE -   A stack (2) of the fuel cells (17) is used to produce electricity. The ion impermeable layer (40) prevents reactant ions or molecules from reaching localised high potential areas of the non-catalysed parts (25,27) of the electrodes (18,32) and corroding the carbon of the electrodes.