An assembly, including: - an SOEC/SOFC-type solid oxide stack operating at a high temperature, including: - a plurality of electrochemical cells each formed by a cathode, an anode and an electrolyte interposed between the cathode and the anode, and a plurality of intermediate interconnectors each arranged between two adjacent electrochemical cells, - a clamping system for the SOEC/SOFC-type solid oxide stack, including an upper clamping plate and a lower clamping plate, between which the SOEC/SOFC-type solid oxide stack is sandwiched, each clamping plate (45, 46) including at least two clamping holes, the clamping system further including: - at least two clamping rods each for extending through a clamping hole of the upper clamping plate and through a corresponding clamping hole of the lower clamping plate for assembling the upper and lower clamping plates to each other, - clamping means (56, 57, 58) at each clamping hole of the upper and lower clamping plates for cooperating with said at least two clamping rods for assembling the upper and lower clamping plates therebetween, - a high temperature sealed coupling system for coupling said SOEC/SOFC-type solid oxide stack to a heating system for gas feed and outlet, the coupling system being detachable and enabling said SOEC/SOFC-type solid oxide stack to be electrically insulated, characterised in that the coupling system includes: - a collector, comprising at least two collecting ducts for gas feed and outlet each provided with a collecting hole positioned facing a corresponding communication hole of at least one of the upper and lower clamping plates, - at least two seals each placed between a collecting hole and a corresponding communication hole. - an SOEC/SOFC-type solid oxide stack operating at a high temperature, including: - a plurality of electrochemical cells each formed by a cathode, an anode and an electrolyte interposed between the cathode and the anode, and a plurality of intermediate interconnectors each arranged between two adjacent electrochemical cells, - a plurality of electrochemical cells each formed by a cathode, an anode and an electrolyte interposed between the cathode and the anode, and a plurality of intermediate interconnectors each arranged between two adjacent electrochemical cells, - a clamping system for the SOEC/SOFC-type solid oxide stack, including an upper clamping plate and a lower clamping plate, between which the SOEC/SOFC-type solid oxide stack is sandwiched, each clamping plate (45, 46) including at least two clamping holes, the clamping system further including: - at least two clamping rods each for extending through a clamping hole of the upper clamping plate and through a corresponding clamping hole of the lower clamping plate for assembling the upper and lower clamping plates to each other, - clamping means (56, 57, 58) at each clamping hole of the upper and lower clamping plates for cooperating with said at least two clamping rods for assembling the upper and lower clamping plates therebetween, - at least two clamping rods each for extending through a clamping hole of the upper clamping plate and through a corresponding clamping hole of the lower clamping plate for assembling the upper and lower clamping plates to each other, - clamping means (56, 57, 58) at each clamping hole of the upper and lower clamping plates for cooperating with said at least two clamping rods for assembling the upper and lower clamping plates therebetween, - a high temperature sealed coupling system for coupling said SOEC/SOFC-type solid oxide stack to a heating system for gas feed and outlet, the coupling system being detachable and enabling said SOEC/SOFC-type solid oxide stack to be electrically insulated, characterised in that the coupling system includes: - a collector, comprising at least two collecting ducts for gas feed and outlet each provided with a collecting hole positioned facing a corresponding communication hole of at least one of the upper and lower clamping plates, - at least two seals each placed between a collecting hole and a corresponding communication hole. - a collector, comprising at least two collecting ducts for gas feed and outlet each provided with a collecting hole positioned facing a corresponding communication hole of at least one of the upper and lower clamping plates, - at least two seals each placed between a collecting hole and a corresponding communication hole.