Abstract: A fuel cell, including: first and second electrochemical cells; a two-pole plate arranged between the first and second electrochemical cells, including a conductor support delimiting a first flow channel facing the first electrochemical cell and extending between an air inlet and a water outlet, and including a first conductive coating attached to the conductor support at the air inlet of the first flow channel and including a second conductive coating fastened to the conductor support at the middle part of the first flow channel, the second conductor coating having an electrical surface resistance greater than that of the first conductive coating.

Abstract: A fuel cell, including: first and second electrochemical cells; a two-pole plate arranged between the first and second electrochemical cells, including a conductor support delimiting a first flow channel facing the first electrochemical cell and extending between an air inlet and a water outlet, and including a first conductive coating attached to the conductor support at the air inlet of the first flow channel and including a second conductive coating fastened to the conductor support at the middle part of the first flow channel, the second conductor coating having an electrical surface resistance greater than that of the first conductive coating.

Abstract: The invention relates to a cooling system for a fuel cell (2), comprising a main heat-transfer-fluid circuit including a main circulation pump (6) and a heat exchanger (8) with the exterior, which feed an upstream pipe (12) supplying the fluid to the cells (4) of the fuel cell, said fluid leaving the cells via a downstream pipe (14) in order to return to the main pump. The system is characterised in that a secondary circuit, comprising a secondary circulation device (30) that circulates the fluid in an alternate manner, is connected in parallel with the main circuit to the upstream (12) and downstream (14) pipes and in that one or more controlled valves (10, 16) allow the main circuit and the secondary circuit to operate independently.

Abstract: The invention relates to a cooling system for a fuel cell, comprising a main heat-transfer-fluid circuit including a circulation pump (6) and a heat exchanger (8) with the exterior, which feed an upstream pipe (12) supplying the fluid to the cells (4) of the fuel cell, said fluid leaving the cells via a downstream pipe (14) in order to return to the main pump. The invention is characterized in that the main circuit comprises a three-port controlled valve (10, 16) on each upstream (12) and downstream (14) pipe, the third available port (10c) of the upstream pipe (12) being connected to the inlet of the pump (6) and the third available port (16c) of the downstream pipe (14) being connected to the outlet of the pump in order to establish a secondary fluid circuit.

Abstract: A high-temperature electrolyser including a stack of electrolysis cells in which steam is made to flow both at a cathode and at an anode. The architecture of the electrolyzer is configured to have each cathode inlet end and anode inlet end close to an oxygen, or respectably hydrogen, collection duct portion. With the structure, a buffer volume of steam is created around the oxygen and hydrogen collectors, which therefore constitutes a simple and effective sealing mechanism within the electrolyser.

Abstract: A high-temperature module for electrolysis of water with improved operational safety, in which steam containing at most 1% hydrogen can be made to flow simultaneously in each cathode and in each anode, as a draining gas, of a stack of cells. The stack of cells is housed in a sealed case and a mechanism for clamping by compression of the stack is included. The risks of leaks likely to cause impairments of efficiency and breakages of all or part of a stack EHT electrolyzer are reduced, while a high level of efficiency is provided due to the fact that satisfactory electrical conduction is maintained by compression of the stack.

Abstract: The invention relates to a cooling system for a fuel cell, comprising a main heat-transfer-fluid circuit including a circulation pump (6) and a heat exchanger (8) with the exterior, which feed an upstream pipe (12) supplying the fluid to the cells (4) of the fuel cell, said fluid leaving the cells via a downstream pipe (14) in order to return to the main pump. The invention is characterised in that the main circuit comprises a three-port controlled valve (10, 16) on each upstream (12) and downstream (14) pipe, the third available port (10c) of the upstream pipe (12) being connected to the inlet of the pump (6) and the third available port (16c) of the downstream pipe (14) being connected to the outlet of the pump in order to establish a secondary fluid circuit.

Abstract: The invention relates to a cooling system for a fuel cell (2), comprising a main heat-transfer-fluid circuit including a main circulation pump (6) and a heat exchanger (8) with the exterior, which feed an upstream pipe (12) supplying the fluid to the cells (4) of the fuel cell, said fluid leaving the cells via a downstream pipe (14) in order to return to the main pump. The system is characterised in that a secondary circuit, comprising a secondary circulation device (30) that circulates the fluid in an alternate manner, is connected in parallel with the main circuit to the upstream (12) and downstream (14) pipes and in that one or more controlled valves (10, 16) allow the main circuit and the secondary circuit to operate independently.

Abstract: A seal between two spaces able to be occupied by two mutually reactive gases, typically oxygen and hydrogen. A buffer chamber is produced between the two spaces of mutually reactive gases, wherein leaks of reactive gases to the buffer chamber are determined to produce a flow which is mainly of diffusive type, for example by molecular or Knudsen diffusion. Such a seal may, for example, find application to production of a seal in an EHT electrolyser or a fuel cell of SOFC type.

Abstract: An electrolyser including a stack of a plurality of elementary electrolysis cells, each cell including a cathode, an anode, and an electrolyte provided between the cathode and the anode. An interconnection plate is interposed between each anode of an elementary cell and a cathode of a following elementary cell, the interconnection plate being in electric contact with the anode and the cathode. A pneumatic fluid is to be brought into contact with the cathodes, and the electrolyser further includes a mechanism ensuring circulation of the pneumatic fluid in the electrolyser for heating it up before contacting the same with the cathodes.

Abstract: A high-temperature electrolyser including a stack of electrolysis cells in which steam is made to flow both at a cathode and at an anode. The architecture of the electrolyser is configured to have each cathode inlet end and anode inlet end close to an oxygen, or respectably hydrogen, collection duct portion. With the structure, a buffer volume of steam is created around the oxygen and hydrogen collectors, which therefore constitutes a simple and effective sealing mechanism within the electrolyser.

Abstract: A process of electrolyzing water at high temperatures implemented by a cell stack reactor, including: a) simultaneously circulating water vapour at each cathode and at each anode as a leaching gas, temperatures of the water vapour at an inlet of each anode and each cathode being lower than high temperatures at which electrolysis is carried out and the water vapour circulating at the anode being at an overpressure with respect to the cathode; b) upon starting the electrolysis, supplying electrical power having a substantially constant electrical voltage across terminals of the stack and maintaining same. In event of breakage of one or more cells, complete destruction of the stack is avoided and high production efficiency is maintained, and efficiency is maintained during ageing.

Abstract: An electrochemistry method to produce a reaction gas of a lesser molar mass than that of an initial constituent of gas or vapor, according to which the gas or vapor of the initial constituent is made to flow, and the reaction gas is recovered in the path in which the initial constituent is made to flow. At least one vortex is created in a zone upstream from the reaction gas recovery zone, wherein the vortex can separate the produced reaction gas from the initial constituent still present to subject the initial constituent to an electrochemical process in the upstream zone. In a high-temperature water electrolysis application according to the method, by the vortex, the produced hydrogen is separated from the surplus steam to subject the surplus stream to an electrolytic process within the electrolyser itself.

Abstract: A high-temperature module for electrolysis of water with improved operational safety, in which steam containing at most 1% hydrogen can be made to flow simultaneously in each cathode and in each anode, as a draining gas, of a stack of cells. The stack of cells is housed in a sealed case and a mechanism for clamping by compression of the stack is included. The risks of leaks likely to cause impairments of efficiency and breakages of all or part of a stack EHT electrolyser are reduced, while a high level of efficiency is provided due to the fact that satisfactory electrical conduction is maintained by compression of the stack.

Abstract: An electrolyser for generating hydrogen including a plurality of elementary electrolysis cells including a cathode, an anode, and an electrolyte provided between the cathode and the anode. An interconnection plate is interposed between the anode of an elementary cell and a cathode of a following elementary cell, in electric contact with the anode and the cathode, and includes a cathodic compartment, an anodic compartment for circulation of fluid to the cathode and the anode respectively, and a chamber for collecting a gas generated at the cathode, separated from the cathodic compartment and the anodic compartment by first and second walls respectively, the first wall at least having a thickness allowing diffusion of the gas through the first wall from the cathodic compartment to the chamber.

Abstract: The invention relates to a bipolar plate for a fuel cell, of the type that comprises anode and cathode bipolar half plates (1, 1?) which are placed next to one another. The central part of each bipolar half plate comprises an active zone (2), while the periphery thereof comprises a plurality of cut-outs (4, 4?, 5, 5?, 6) which are intended to form at least two oxidant tanks, two fuel tanks and two coolant tanks. Moreover, at least one bipolar half plate comprises at least one connecting rib (8, 8?, 10, 12) between a peripheral cut-out and the active zone. Projecting out from the outer face, each coolant tank cut-out is surrounded by a sealing rib (7, 7?) and the periphery of each bipolar half plate comprises a rib (15, 15?) for sealing the active zone, which connects the coolant tank sealing ribs and which surrounds the oxidant and fuel tanks. Furthermore, each channel formed by a rib segment (15, 15?) between two coolant tanks is blocked by a blocking means (17, 17?).

Abstract: The invention concerns an assembly typically operating at above 500° C., between two components of different mean thermal expansion coefficients, between which a seal is inserted having a coefficient which differs by a value of at least 1.10?6 K?1 from the coefficient of at least one of the two components. According to the invention: below a threshold temperature, the seal undergoes orthogonal compression obtained by constant clamping of the two components towards each other, above the threshold temperature, the seal undergoes orthogonal compression by clamping and radial compression obtained by the sliding of seal surfaces bearing upon at least one of the components until an end portion of the seal is placed under radial compression against the same component, this portion being free of any contact below the threshold temperature. The seal is designed not to reach its creep rupture point during a cycle of use of predetermined duration.

Abstract: An electrolyser for generating hydrogen including a plurality of elementary electrolysis cells including a cathode, an anode, and an electrolyte provided between the cathode and the anode. An interconnection plate is interposed between the anode of an elementary cell and a cathode of a following elementary cell, in electric contact with the anode and the cathode, and includes a cathodic compartment, an anodic compartment for circulation of fluid to the cathode and the anode respectively, and a chamber for collecting a gas generated at the cathode, separated from the cathodic compartment and the anodic compartment by first and second walls respectively, the first wall at least having a thickness allowing diffusion of the gas through the first wall from the cathodic compartment to the chamber.

Abstract: An electrolyser including a stack of a plurality of elementary electrolysis cells, each cell including a cathode, an anode, and an electrolyte provided between the cathode and the anode. An interconnection plate is interposed between each anode of an elementary cell and a cathode of a following elementary cell, the interconnection plate being in electric contact with the anode and the cathode. A pneumatic fluid is to be brought into contact with the cathodes, and the electrolyser further includes a mechanism ensuring circulation of the pneumatic fluid in the electrolyser for heating it up before contacting the same with the cathodes.

Abstract: The invention relates to a fuel cell bipolar plate (22) comprising at least one ridge (47, 23a, 33a, 40a, 27a, 35a, 41a, 23a) on at least one of the faces (51) thereof, such as seal at least one fluid circuit in the cell from among the oxidant, fuel and coolant inlet circuits and the oxidant, fuel and coolant outlet circuits, said circuits being formed by stacking openings which are provided in the plate (22) and which form an inlet and an outlet for the oxidant and the fuel (33, 40, 35, 41) respectively and openings which form an inlet and an outlet for the coolant (23, 27) respectively during the assembly of the constituent cells (1) of the fuel cell.