Assembly, comprising: - a solid-oxide stack of the SOEC/SOFC type functioning at high temperature, comprising: - 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 top end plate and a bottom end plate, between which the plurality of electrochemical cells and the plurality of intermediate interconnectors are gripped, - a system for gripping the solid-oxide stack of the SOEC/SOFC type, comprising a top clamping plate and a bottom clamping plate, between which the solid-oxide stack of the SOEC/SOFC type is gripped, each clamping plate (45, 46) comprising at least two clamping orifices, the clamping system further comprising: - at least two clamping rods intended each to extend through a clamping orifice in the top clamping plate and through a corresponding clamping orifice in the bottom clamping plate to enable the top and bottom clamping plates to be assembled together, - clamping means (56, 57, 58) at each clamping orifice of the top and bottom clamping plates intended to cooperate with said at least two clamping rods in order to enable the top and bottom clamping plates to be assembled together, characterized in that it comprises a heat exchange system formed at least partly by at least two hollow clamping rods of the clamping system inside which gases or liquids to be superheated circulate, intended to enter said stack, or a heat-transfer fluid to be preheated circulates, intended to another function than entering said stack, and in that said at least two hollow clamping rods each comprise a heat-transfer fluid and an inlet end for the heat-transfer fluid to be preheated and an outlet end for the preheated heat-transfer fluid, and/or in that the heat exchange system is a system for superheating the gases at the inlet of the solid-oxide stack of the SOEC/SOFC type, formed at least partly by at least two hollow clamping rods of the clamping system, each comprising said gases or liquids to be superheated and an inlet end and an outlet end, inside which said gases or liquids to be superheated circulate, the assembly comprising an inlet pipe into the stack fluidically connected to the outlet end of at least one hollow clamping rod. - a solid-oxide stack of the SOEC/SOFC type functioning at high temperature, comprising: - 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 top end plate and a bottom end plate, between which the plurality of electrochemical cells and the plurality of intermediate interconnectors are gripped, - 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 top end plate and a bottom end plate, between which the plurality of electrochemical cells and the plurality of intermediate interconnectors are gripped, - a system for gripping the solid-oxide stack of the SOEC/SOFC type, comprising a top clamping plate and a bottom clamping plate, between which the solid-oxide stack of the SOEC/SOFC type is gripped, each clamping plate (45, 46) comprising at least two clamping orifices, the clamping system further comprising: - at least two clamping rods intended each to extend through a clamping orifice in the top clamping plate and through a corresponding clamping orifice in the bottom clamping plate to enable the top and bottom clamping plates to be assembled together, - clamping means (56, 57, 58) at each clamping orifice of the top and bottom clamping plates intended to cooperate with said at least two clamping rods in order to enable the top and bottom clamping plates to be assembled together, - at least two clamping rods intended each to extend through a clamping orifice in the top clamping plate and through a corresponding clamping orifice in the bottom clamping plate to enable the top and bottom clamping plates to be assembled together, - clamping means (56, 57, 58) at each clamping orifice of the top and bottom clamping plates intended to cooperate with said at least two clamping rods in order to enable the top and bottom clamping plates to be assembled together,