flow of hydrogen containing fuel to the anode followed by quickly displacing the residual hydrogen with air by blowing air through the anode fuel flow field a sufficiently fast purging of the anode flow field with air eliminates the need for purging with an inert gas such as nitrogen application_number US 30530002 A description in fig1 a fuel cell system 100 is shown the system includes a fuel cell 102 comprising an anode 104 a cathode 106 and an electrolyte layer 108 disposed between the anode and cathode the anode includes an anode substrate 110 having an anode catalyst layer 112 disposed thereon on the side of the substrate facing the electrolyte layer 108 the cathode includes a cathode substrate 114 having a cathode catalyst layer 116 disposed thereon on the side of the substrate facing the electrolyte layer 108 the cell also includes an anode flow field plate 118 adjacent the anode substrate 110 and a cathode flow field plate 120 adjacent the cathode substrate 114 the cathode flow field plate 120 has a plurality of channels 122 extending thereacross adjacent the cathode substrate forming a cathode flow field for carrying an oxidant preferably air across the cathode from an inlet 124 to an outlet 126 the anode flow field plate 118 has a plurality of channels 128 extending thereacross adjacent the anode substrate forming an anode flow field for carrying a hydrogen containing fuel across the anode from an inlet 130 to an outlet 132 each cell also includes a cooler 131 adjacent the cathode flow field plate 120 for removing heat from the cell such as by using a water pump 134 to circulate water through a loop 132 that passes through the cooler 131.