gas produced by co electrolysis of the steam and the reactive heat exchange gas is recovered in the port 66 according to a second or a third alternative form when the heat exchange gas is injected via the slit 701 or the slit 702 of the central metal sheet 7 the oxygen o 2 optionally enriched by the heat exchange gas is recovered in the port 63 the course of the heat exchange gas injected in supplying within an interconnector 5 is represented diagrammatically more precisely in fig1 to 15 the course of the air as draining gas injected within an interconnector 5 is represented diagrammatically more precisely in fig1 and 17 the course of the steam injected within an interconnector 5 is represented diagrammatically more precisely in fig1 and 19 although not illustrated when the heat exchange gas capable of removing the heat is in addition a fuel a process of operation of a fuel cell incorporating interconnectors 5 according to the invention described above for its part comprises the following stages the first ports 61 71 81 are supplied with air and or with oxygen and simultaneously the second ports 62 72 82 are supplied with the heat exchange gas the fifth ports 65 75 85 are supplied with fuel the water produced and if appropriate the surplus fuel and if appropriate the heat exchange gas introduced via the third slit 67 u2032 of the end metal sheet 6 are recovered in the sixth ports 66 76 86 and simultaneously the heat exchange gas is recovered in the fourth ports 64 74 84 and simultaneously the air and or the oxygen is are recovered in the third ports 63 73 83 when the heat exchange gas capable of removing heat is in addition an.