Spacer for water electrolysis cell

Abstract

The invention relates to a spacer (5) for a water electrolysis cell, the spacer being configured to support a separator, the separator comprising at least an inlet (7) and an outlet (8), the inlet (7) and the outlet (8) being configured to allow water to flow within the water electrolysis cell, the spacer (5) comprising a recess (9) configured to be occupied by the separator and in fluid communication with the inlet (7) and the outlet (8), the spacer (5) further comprises at least one distribution region (10) connecting the inlet (7) or the outlet (8) to the recess (9), characterized in that the distribution region (10) comprises at least one laminar flow member (14) extending along an edge (17, 18) of the recess (9). The invention also relates to an electrolytic cell comprising such a spacer (5).

Description

Technical Field

[0001] Generally, electrolysis is a technique that allows non-spontaneous chemical reactions to be carried out using a direct current flowing between two electrodes placed face to face, which are called the anode and the cathode and are separated by an ion-conducting medium called the electrolyte. The electrodes, which can be solid or porous, can be of different types (e.g., plates, sheets, grids). Each of the two half-reactions requires an electrocatalyst configured to maximize its kinetics. The electrocatalyst, usually made of an expensive material, is deposited on the surfaces of the anode and the cathode, on the faces in contact with the electrolyte.

[0002] The present invention more particularly relates to the field of water electrolysis, which consists of dissociating water molecules into gaseous molecular oxygen and molecular hydrogen. Then, the molecular oxygen and molecular hydrogen formed by water electrolysis can be used as consumables in the chemical industry. The water electrolysis reactor takes the form of a series of individual cells stacked one on top of the other, electrically connected in series and fluidically connected in parallel. The fluid flows tangentially to the plane of each cell. The electric current flows in a direction perpendicular to the plane of the cell. The charge carriers are electrons in the metal phase and ions in the electrolyte. Each individual water electrolysis cell is divided into two compartments, called the anode structure and the cathode structure. The type of separator used depends on the electrolysis technique. For example, there are electrolysis techniques that use a polymer membrane with cationic conduction (by proton conduction) or anionic conduction (by hydroxide ion conduction) as the separator. Other techniques use a porous thermoplastic separator or a ceramic separator. Background Art

[0003] A specific example is the electrolysis of liquid water using acidic polymer electrolyte technology (PEM stands for proton exchange membrane or polymer electrolyte membrane). The polymer membrane (which has a typical thickness between 50 and 250 microns) is a solid electrolyte in which the ionic charge carriers remain confined. The electrocatalysts are deposited on both faces of the membrane. Thus, the polymer membrane is coated with two catalytic layers, whose typical thickness is between a few microns and several tens of microns. The two catalytic layers form the two electrodes of the cell. This membrane-electrocatalyst assembly is called a CCM (catalyst-coated membrane). A water electrolysis reactor, such as a proton exchange membrane type water electrolysis reactor, includes two liquid water injection wells and two two-phase mixture collection wells. Each compartment of each cell has a water inlet point (liquid or vapor, depending on the technology) supplied by the injection well and an outlet point for the reaction mixture (single-phase or two-phase, depending on the technology) connected to the collection well. In the simplest case, a single electrochemical reactor is connected to two separate, closed fluid (electrolyte) circulation loops: an anode loop and a cathode loop. The anode injection well and the anode collection well are fluidly connected to the anode loop. The cathode injection well and the cathode collection well are fluidly connected to the cathode loop. Liquid water circulates in each of these two loops in an internal return direction from the injection well to the collection well by means of a pump. Each loop includes various functional units, for example, a liquid-gas separator for separating and collecting the gases produced by the reaction, a heat exchanger for extracting the heat generated in the cell during electrolysis, a resin bed for controlling the conductivity of the circulating water, a pump for circulating the water in the loop, and various pressure, temperature, and flow rate sensors for controlling the operation of the control command machine. There are more complex cases where several reactors are fluidly connected in series or in parallel electrically, each reactor having separate or common anode and cathode loops. In operation, liquid water is injected into each compartment of each cell by a pump, and a two-phase mixture (liquid water and gas produced in the cell during electrolysis) is collected at the outlet of each compartment. A mixture of liquid water and oxygen is collected at the outlet of the anode structure of each cell, and a mixture of liquid water and hydrogen is collected at the outlet of the cathode structure of each cell. The flow of liquid water through the anode structure of each cell serves both to fuel the electrolysis reaction and to cool the anode structure, since the oxygen evolution reaction is exothermic. The flow of liquid water through the cathode structure of each cell serves both to collect the electroosmotic water passing through the membrane and to cool the cathode, since the hydrogen evolution reaction is exothermic. Summary of the Invention

[0004] The present invention first relates to a spacer for a water electrolysis cell, the spacer being configured to support a separator and including at least one inlet and one outlet configured to allow water to flow through the water electrolysis cell. The spacer includes a recess configured to be occupied by the separator and in fluid communication with the inlet and the outlet. The spacer further includes at least one distribution area connecting the inlet or the outlet to the recess. The innovation lies in that the distribution area includes at least one laminar member extending along the edge of the recess.

[0005] The present invention basically relates to a frame, which is preferably made of an injectable thermoplastic material, has a small thickness, such as a few millimeters, is recessed in the middle, preferably has a square or rectangular geometry, is pierced with preferably circular holes to allow fluid flow, is equipped with injection wells allowing fluid to enter the cell compartment and injectors and collectors allowing the reaction fluid to leave the cell compartment and enter the collection well, is equipped with several seals to ensure fluid tightness between the inside and the outside of the reactor, and includes a column or tooth assembly configured to ensure uniform distribution of the flowing fluid in each compartment of each cell. The difficulty for those skilled in the art is to ensure a uniform and constant water flow rate at each point in each compartment of each cell of a water electrolysis reactor in order to properly supply and cool each electrode in each compartment of each cell.

[0006] When no special precautions are taken to control the fluid distribution in the cell compartments, the water distribution within each cell and the water distribution from one cell to another are not optimal, that is, the water flow through each compartment of each cell is non-uniform and varies from one place to another. For example, in the case where a rectangular spacer is equipped with an inlet point at one of its four corners and an outlet point opposite on the diagonal, the water flow will tend to circulate along the shortest hydraulic path (the path with the lowest hydraulic resistance), that is, along the diagonal of the spacer. In this case, the water is not evenly distributed on the active electrochemical surface, resulting in non-uniform operation, loss of energy efficiency, and accelerated aging of the reactor. In addition, the flow of water along the shortest path is rapid, which tends to generate hydraulic turbulence, thus further disturbing the operation.

[0007] The present invention describes a spacer that allows these problems to be overcome and, in particular, ensures uniform water circulation at each point in each compartment of each cell of a water electrolysis module. By controlling the injection pressure drop, the uniform water circulation also indirectly contributes to ensuring the good operation of the electrolysis cell as a whole. Such a water electrolysis cell spacer is also designed to accommodate a separator, such as a polymer electrolyte membrane.

[0008] The spacer can be made of different materials, such as thermoplastic materials for "low-temperature" applications, such as proton exchange membrane cells, anion exchange membrane cells, or alkaline electrolysis cells.

[0009] The spacer according to the invention is preferably a frame made of a thin injectable thermoplastic material, preferably in the shape of a square or rectangle, comprising at least one inlet and one outlet allowing water to circulate within the water electrolysis cell.

[0010] Advantageously, the inlet may comprise a fluid injector and an injection well, and the outlet may comprise a collection well and a fluid collector. The spacer is recessed at its center and has a peripheral support provided with a seal against which the separator is pressed in order to divide the cell into two distinct compartments, an anode and a cathode. The recess of the spacer is in fluid communication with the anode circuit and the cathode circuit. The fluid injector connects the inlet of the injection well to a fluid distribution area, there may be one fluid injector per compartment, and at least one fluid collector connects the fluid distribution area to the collection well at the outlet. The spacer is characterized in that the fluid distribution area comprises at least one laminar flow member which extends along the edge of the recess, i.e. along one of the inner sides of the spacer which is in fluid contact with the central recess.

[0011] The laminar flow member generates a plurality of straight water flows.

[0012] Furthermore, the space in each compartment located between the inlet and outlet laminar components comprises a metal grid which aims to ensure electrical contact perpendicular to the plane of each cell and also generates a fluid pressure drop which also contributes to the parallelism of the water flows circulating in the compartments of the cell.

[0013] Due to this combination of fluid and mechanical characteristics, the spacer which is the subject of the present invention will allow the water flows circulating in the two compartments of each elementary cell to flow uniformly along the active surface of each compartment, which ensures uniform operation and thus extends the service life of the electrolysis cell while maximizing the energy efficiency of the reactor. The spacer which is the object of the present invention also ensures the same level of fluid uniformity in each compartment of each cell of the electrochemical reactor, regardless of their number. The characteristics of the spacer are independent of its size. The spacer has fluid, mechanical and dimensional characteristics adapted to the size of the electrolysis cell.

[0014] The recess at the inlet of each cell compartment faces the active surface of the cell. After entering the cell compartment, the laminar flow of water flows along this recess and uniformly cools the active surface of the cell, such as the surface of one of the electrodes. This cooling takes place by heat exchange, so the temperature of the water increases as it flows along the recess. The heated water flow then leaves the cell via an outlet located opposite the inlet point.

[0015] The fluid distribution area is arranged between the inlet and the recess and / or between the recess and the outlet. It is within the distribution area that the flow rate of water is homogenized, in particular due to the laminar flow member. This is positioned as close as possible to the recess. For example, when the distribution area is arranged between the inlet and the recess, the laminar flow member is arranged along the edge of the recess, which corresponds to the edge through which water enters the recess. This ensures the direct formation of a laminar flow of water upon entry into the recess.

[0016] According to a feature of the invention, the laminar flow member comprises a plurality of teeth, the plurality of teeth being spaced apart to form channels, the channels being configured to achieve a straight flow of water. In other words, the channels are formed between two separate teeth. The channels are small so as to generate a pressure drop that contributes to the uniform distribution of the water flow rate along the injection channels. The channels are formed by two adjacent teeth, the teeth having sides that are preferably parallel or substantially parallel to each other. The teeth impede the flow of water and force it to flow within the channels, in order to enable parallel fluid lines in the compartment. Thus, the water flow from the inlet and / or the recess is distributed across the respective channels and exits from the latter as a laminar flow. Advantageously, at least some of the channels are configured to be oriented parallel to the flow direction of the water flow. Even more advantageously, the combination of channels is oriented parallel to the flow direction of the water flow, so as to increase its uniformity after passing through the laminar flow member. In this configuration, the shape of the laminar flow member resembles a comb.

[0017] According to a feature of the invention, the teeth of the laminar flow member are configured to provide resistance against the support member at the level of the laminar flow member. In addition to ensuring the laminar flow of water, the teeth also provide mechanical resistance perpendicular to the plane of the spacer, which is compatible with the stacking of several cells in series, possibly up to dozens or even hundreds of cells. For example, it is the height of the teeth that ensures the required resistance. The electrolytic cells are integrated into an electrolysis module that includes a plurality of electrolytic cells stacked one on top of the other. Thus, the spacer according to the invention is integrated into this stack and is thus pressed against at least one adjacent support member. The mechanical properties of the teeth, in particular their rigidity and their resistance to deformation, prevent the teeth from being deformed by the support members generated by the stacking, thus allowing the channels to remain intact and operational to stratify the water flow when the reactor is shut down and compressed to ensure the sealing of the cells. The support member opposite the laminar flow member also contributes to defining the cross-section of the channels of the channels.

[0018] According to a feature of the invention, the distribution area includes a distribution chamber that extends between the inlet or the outlet and the laminar flow member. The distribution chamber helps to distribute the water flow across the entire laminar flow member, i.e., along the edge of the recess. The distribution chamber ensures that the flow then circulates over the entire surface of the recess, such that the local water flow rate is uniform and the electrodes are cooled uniformly over their entire surface.

[0019] According to a feature of the present invention, the distribution chamber includes a plurality of deflection members. The deflection members can have various shapes, mainly because they block the water flow, so that the water flow is correctly dispersed throughout the distribution chamber, and then flows in a laminar flow and passes through each channel of the flow member as evenly as possible.

[0020] According to a feature of the present invention, the plurality of deflection members are configured to provide resistance against the support at the level of the distribution chamber. Similar to the teeth of the laminar member, the deflection members do not deform when pressed against the distribution chamber during stacking. Space is maintained within the distribution chamber so that water can always flow through and be correctly distributed.

[0021] According to a feature of the present invention, at least one deflection member is oblong. The elongated deflection member further guides the water flow in a preferred direction. For example, the oblong deflection member can have a main direction parallel to the water flow to promote its laminarity. The oblong deflection member can also have a direction perpendicular to the main direction of the water flow so that the latter flows at least partially towards the part of the distribution chamber that is farthest from the inlet or the recess, thereby promoting the uniformity of the water flow.

[0022] According to a feature of the present invention, the recess has a rectangular shape and has two longitudinal edges and two transverse edges, and the laminar member is arranged along one of the longitudinal edges. The longitudinal edges are parallel in pairs, and so are the transverse edges. The laminar member is arranged such that the water flow passes through the recess from one longitudinal edge to the other. This configuration allows the water flow to pass through the recess with a minimum size. This ensures that the water flow does not overheat when exchanging heat with the electrode opposite to the recess.

[0023] According to a feature of the present invention, the inlet and the outlet are located between two straight lines passing through the transverse edges. In other words, the distribution chamber is located between the laminar member and the inlet or the outlet in the transverse direction defined by the side edges of the recess.

[0024] According to a feature of the present invention, the inlet and the outlet are symmetrically arranged with respect to the center point of the spacer. For example, if the inlet is centered with respect to the longitudinal edge, the outlet is also centered with respect to the longitudinal edge. If the input part is offset from the center of the longitudinal edge in the longitudinal direction, the output part is also offset from the center of the longitudinal edge in the longitudinal direction, but in the direction opposite to the offset of the input part. In such a configuration, the section extending between the inlet and the outlet has a direction inclined with respect to the longitudinal edge of the recess and with respect to the transverse edge of the recess.

[0025] According to the features of the present invention, the distribution area is a first distribution area, and the spacer includes a second distribution area that is at least partially symmetric with respect to the central axis of the recess relative to the first distribution area. The central axis is parallel to the direction of the longitudinal edge. Thus, the spacer includes two distribution areas, one distribution area is between the inlet and the recess, and one distribution area is between the recess and the outlet. Each of the distribution areas thus includes a first laminar member and a second laminar member, and the first laminar member and the second laminar member extend along the longitudinal edge defining its own distribution area. The first distribution area further includes a first distribution chamber extending between the inlet and the first laminar member, while the second distribution area includes a second distribution chamber extending between the second laminar member and the outlet.

[0026] According to the features of the present invention, the spacer includes a first face and a second face, the spacer includes an inlet and an outlet, the inlet and the outlet are configured to allow water to flow within the water electrolysis cell, and the spacer further includes at least one distribution area connecting the inlet or the outlet to the recess, the distribution area is formed in the thickness of the spacer by leading to the first face, and the distribution area is formed in the thickness of the spacer by leading to the second face. The recess inside the spacer is divided into two compartments, namely an anode structure and a cathode structure, separated by a separator.

[0027] The first face includes an inlet, one or more distribution chambers and an outlet. The second face includes an inlet, one or more distribution chambers and an outlet.

[0028] The operation of the spacer on the second face is the same as that of the spacer on the first face, that is, devices are used to distribute and homogenize the water flow to cool one of the electrodes. However, the structural features of the elements on each face can vary according to the cooling conditions and / or the cooling objectives.

[0029] According to the features of the present invention, the distribution area includes at least one laminar device extending along the edge of the recess. The function of the laminar device is the same as that of the laminar member on the first face, that is, to homogenize the water flow circulating within the distribution area.

[0030] The present invention also encompasses a water electrolysis cell, which includes an anode structure, a cathode structure and a separator between the anode structure and the cathode structure. The water electrolysis cell includes the spacer as described above, and the spacer supports the anode structure, the cathode structure and the separator. Supplied with current, the electrolysis cell forms hydrogen and oxygen from water. The spacer helps to ensure uniform and reasonably distributed cooling over the entire surface of at least one of the electrodes of the electrolysis cell.

[0031] The present invention also encompasses a water electrolysis module, which includes a plurality of electrolysis cells as described above, and these electrolysis cells are stacked on top of another electrolysis cell. Description of the Drawings

[0032] On the one hand, by reading the following description, and on the other hand, by referring to the attached schematic diagrams which show a plurality of exemplary embodiments in an indicative and non - limiting manner, other features and advantages of the present invention will become more clearly apparent. In the drawings:

[0033] Figure 1 is a schematic diagram showing an exploded view of a water electrolysis cell including a spacer according to the present invention,

[0034] Figure 2 is a view of the first face of the spacer,

[0035] Figure 3 is a view of the second face of the spacer opposite the first face,

[0036] Figure 4 is a cross - sectional view of a part of the spacer,

[0037] Figure 5 is a diagram of the electrolysis module. Detailed Description

[0038] Figure 1 An electrolysis cell 1 is shown, in particular an exploded cross - sectional view showing the stacking of elements inside the electrolysis cell 1. A direct - current flows through the electrolysis cell 1 to decompose water into oxygen and hydrogen.

[0039] The electrolysis cell 1 includes a separator 2 between an anode structure 3 and a cathode structure 4. The anode structure 3 is typically made of titanium, and the cathode structure 4 is typically made of titanium but may contain carbon elements. The anode structure 3 and the cathode structure 4 are directly or indirectly connected to the positive and negative terminals of an external DC generator (not shown). For example, if the electrolysis cell is a proton - exchange membrane cell or an anion - exchange membrane cell, the separator 2 can be a membrane - electrocatalyst assembly. In the case of an alkaline electrolysis cell, the separator is a diaphragm.

[0040] Generally speaking, the present invention can also be applied to other types of cells, such as solid oxide electrolysis cells.

[0041] ​​​​​The anode structure 3 includes a bipolar plate 31 shared with the upper adjacent cell, an anode grid 32, and an anode porous element 33. The anode porous element 33 generally includes titanium particles or fibers sintered together in a vacuum. The anode structure 3 may also include an attachment device 34 adapted to the shape of the electrolytic cell 1, which allows the attachment of the bipolar plate 31, the grid 32, and the porous element 33. These three elements of the anode structure 3 allow for the optimization of electrical conductivity and mechanical resistance and contribute to good fluid distribution. The cathode structure 4 also includes a second bipolar plate 41 shared with the lower adjacent cell, a cathode grid 42, and a cathode porous element 43 having the same nature as or made of carbon as the anode porous element 33. All these elements have the same nature as the elements integrated into the anode structure 3. When the electrolytic cell 1 is in operation, i.e., when a direct current passes through the electrolytic cell 1, the electrolytic cell 1 gives off heat. The anode structure 3 and the cathode structure 4 are heated by the Joule effect, and the polymer membrane of the separator 2 is also heated due to its ionic conduction. The catalytic layer of the separator 2 also generates heat. Therefore, the electrolytic cell 1 must be continuously cooled to keep its temperature below a maximum value, which depends on the chemical nature of the membrane of the separator 2 and is generally below 100 °C, in order to extend its service life and prevent premature damage. For this purpose, a water circuit (not shown) allows water to flow through at least the anode structure or the cathode structure in order to cool it or them. The electrolytic cell 1 also includes a spacer 5 that supports the separator 2 in its middle. The anode structure 3 and the cathode structure 4 are assembled into recesses in the center of the spacer 5. The bipolar plates 31 and 41 cover the spacer 5 and hold the elements of the anode structure 3 and the cathode structure 4 in place and in contact with each other. In this way, the porous anode element 33 and the cathode element 43 are in contact with the catalytic layer of the separator 2. The spacer 5 also helps with the circulation of water in each of the two compartments in order to supply water to the reaction and ensure the cooling of the electrodes, as will be described in detail later. The electrolytic cell 1 may also be placed on a support plate 6.

[0042] Figure 2 is a diagram of the spacer 5 as viewed from above, i.e., the spacer 5 viewed in a direction perpendicular to the plane of the electrolytic cell 1. This is a view of the anode face. More specifically, Figure 2 shows a first face 51 of the spacer 5, which in this case is the anode face of the spacer.

[0043] The spacer 5 is a parallelepiped solid element with a square or rectangular base. The main plane extends in a first direction called the longitudinal direction L1 and in a second direction called the transverse direction L2.

[0044] The thickness of the frame extends in a direction perpendicular to the main plane. The spacer 5 includes two through-holes, a fluid inlet 7 and a fluid outlet 8. Preferably, in the electrolytic cell 1, the inlet 7 includes a fluid injector and an injection well, and the outlet 8 includes a collection well and a collector, for example, geometrically opposite to the fluid injector. In as Figure 1In the electrolysis reactor shown, which consists of a stack of multiple individual electrolytic cells, the stack of spacers 5 forms injection wells and collection wells. The water flowing through the injection wells passes through the structure of the spacer 5. The two-phase mixture, namely the mixture of water and oxygen or hydrogen, then leaves the compartments of the spacer 5 and reaches the collection wells that form the outlet 8. The inlet 7 and its injector and the outlet 8 and its collector ensure the inlet of water and the outlet of the two-phase mixture respectively. Therefore, the inlet 7 and the outlet 8 allow water to flow into and out of the electrolytic cell to supply and cool the electrolytic cell.

[0045] The spacer 5 also includes recesses 9, as Figure 1 shown, the recesses 9 are configured to be filled particularly by the separator and by the anode structure and the cathode structure of the electrolytic cell. Thus, when water enters the electrolytic cell and flows through it, it flows parallel to the main plane formed by the longitudinal direction L1 and the transverse direction L2 of the separator, where the recesses 9 are in fluid communication with both the inlet 7 and the outlet 8. The spacer 5 also includes at least one distribution area 10 between the recesses 9 and the inlet 7 or the outlet 8. The distribution area 10 provides a fluid connection between the inlet 7 and the recesses 9 or between the recesses 9 and the outlet 8. In Figure 2 it, the spacer 5 includes a first distribution area 11 arranged between the inlet 7 and the recesses 9, and a second distribution area 12 arranged between the recesses 9 and the outlet 8. The first distribution area can be referred to as the input distribution area, while the second distribution area can be referred to as the output collection area.

[0046] Although Figure 2 and Figure 3 show the symmetry between the inlet and the outlet of the same cell, asymmetries in size and geometry are also possible. This is because, during the reaction, the volume of the gas produced increases. The cross-sections of the wells can be different, as Figure 2 and Figure 3 shown. This difference in cross-section is achieved to accommodate the difference in flow rates between the two compartments, since the flow rate of the water flowing through the anode circuit is greater than the flow rate of the water flowing through the cathode circuit. Therefore, the diameter of the wells in the same compartment can be adjusted to accommodate the increase in volume flow rate caused by gas formation during the reaction. Geometric differences between the two can also be envisioned to facilitate the expulsion of bubbles. In other words, the present invention also relates to a spacer in which the wells and / or the distribution / distribution areas can have different sizes and geometries at the inlet and the outlet.

[0047] The second distribution area 12 is at least partially symmetric with the first distribution area 11 with respect to the central axis 13 of the recesses 9, and the central axis 13 is parallel to the longitudinal direction L1. A special feature of the spacer 5 according to the present invention is that the distribution area 10 (whether it is the first distribution area 11 or the second distribution area 12) includes a laminar member 14 extending along one edge of the recesses 9. In Figure 2In it, the first distribution area 11 includes the first laminar flow member 15, while the second distribution area 12 includes the second laminar flow member 16. The function of the laminar flow member 14 is to equalize the water flow circulating in the electrolytic cell by making the water flow forming the flow between the inlet 7 and the outlet 8 parallel. This reduces the turbulence in the water flow and ensures its uniform circulation, thus contributing to higher cooling efficiency. The recess 9 has an overall rectangular shape including two longitudinal edges 17 and two side edges 18 that are pairwise parallel. More specifically, the recess 9 includes a first longitudinal edge 17a and a second longitudinal edge 17b, where the first longitudinal edge 17a corresponds to the longitudinal edge 17 closest to the inlet 7, and the second longitudinal edge 17b corresponds to the longitudinal edge 17 closest to the outlet 8. The side edges 18 are perpendicular to the longitudinal edges 17. The spacer 5 is arranged to flow horizontally parallel to the transverse direction L2 so as to flow along the electrolytic cell at the shortest possible distance, with the aim that the water does not reach too high a temperature at the outlet, in order to protect the separator with limited thermal stability and to ensure that the current flows uniformly through the electrolytic cell in a direction parallel to the thickness of the spacer 5. Thus, the first laminar flow member 15 extends along the first longitudinal edge 17a, preferably over the entire first longitudinal edge 17a, while the second laminar flow member 16 extends along the second longitudinal edge 17b, preferably over the entire second longitudinal edge 17b. Each laminar flow member 14 includes teeth 29 that define channels 19, and the channels 19 are bounded by two adjacent teeth 29. It is through the circulation through these channels 19 that the water flows forming the water flow circulate parallel to each other. Preferably, at least some of the channels 19 have a main direction parallel to the transverse direction L2 (i.e., the flow direction of the cooling water flow). More preferably, the combination of the channels 19 is parallel to the transverse direction L2. The laminar flow member 14 then has a comb shape, and its geometry is optimized according to the hydraulic flow through the electrolytic cell in order to meet the constraints imposed on the maximum outlet temperature. In one example, the combs forming the laminar flow members 14, 16 may have different hydraulic diameters. Each distribution area 10 also includes a distribution chamber 20 that extends between either the inlet 7 and the outlet 8 at one of the laminar flow members 14. In Figure 2 it, the first distribution area 11 includes a first distribution chamber 21 located between the inlet 7 and the first laminar flow member 15. The second distribution area 12 includes a second distribution chamber 22 located between the second laminar flow member 16 and the outlet 8. The lengths of the first distribution chamber 21 and the second distribution chamber 22 can be adjusted according to the hydraulic flow through the cell in order to meet the constraints imposed on the maximum outlet temperature. Thus, according to Figure 2The structure of the spacer 5 shown is such that the water for operating and cooling the electrolytic cell enters the cell via the inlet 7, then passes through the first distribution chamber 21, the first laminar member 15, and then through the recess from the first longitudinal edge 17a to the second longitudinal edge 17b. When leaving the recess 9, the two-phase mixture passes through the second laminar member 16, then through the second distribution chamber 22, and then leaves the electrolytic cell to return to the outlet 8. The first distribution chamber 21 and the second distribution chamber 22 are formed in one thickness of the spacer 5 and lead to the first face 51. Each distribution chamber 20 may include a plurality of deflection members 23 configured to block the water flow from the inlet 7 to the outlet 8. The deflection members 23 allow the flow to be evenly distributed to the combination of channels 19. Preferably, the deflection members 23 are shaped to equalize the water flow and / or direct the water flow, in particular to parallelize the water flow through the electrolytic cell. Near the inlet 7 or the outlet 8, the deflection members 23 have an oblong shape extending mainly parallel to the flow of the water, so as to ensure at least partial equalization when the water enters the first distribution chamber 21 or before leaving the spacer 5. Each distribution chamber 20 may also include other oblong deflection members 23 extending mainly perpendicular to the flow of the water. These deflection members 23 ensure the distribution of water to the part of the first distribution chamber 21 farthest from the inlet 7. Due to the deflection members 23 in the first distribution chamber 21 and the channels 19 in the first laminar member 15, the water flow is laminar and evenly distributed along the electrodes to be cooled, thus ensuring the best cooling capacity. Preferably, the inlet 7 and the outlet 8 are symmetrically arranged with respect to the center point Y of the spacer 5. In Figure 2 it, the inlet 7 and the outlet 8 are offset from each other in the longitudinal direction L1 and in opposite directions. The inlet 7 and the outlet 8 can also be both arranged to be centered with respect to the longitudinal edge 17. However, the inlet 7 and the outlet 8 are positioned such that they are between two straight lines Z1, Z2 passing through the side edge 18.

[0048] The spacer 5 further includes a sealing member 24 extending around the inlet 7, the outlet 8, the distribution area 10, and the recess 9. The sealing member 24 prevents water leakage and ensures the water flow as described above. The spacer 5 also includes internal seals located below each longitudinal edge 17 and each transverse edge 18 to prevent water from penetrating between the edges and the separator.

[0049] Figure 2 It is also shown that the spacer 5 further includes an inlet 25 and an outlet 26. However, the inlet 25 and the outlet 26 are located outside the sealing member 24 and are not fluidly connected to the assembly of the above elements, but are used to ensure the water flow along the face opposite to the first face 51 of the spacer 5.

[0050] Figure 3 The second face 52 of the spacer 5 is shown, which corresponds to Figure 2The opposite face of the first face 51 described in. At the level of the second face 52, the inlet 25 and the outlet 26 are fluidly connected. Thus, it should be understood that the first water flow circulating along the first face 51 ensures the cooling of one of the compartments in the electrolytic cell, while the second water flow circulating along the second face 52 ensures the cooling of the other compartment in the electrolytic cell. For example, the first face 51 corresponds to the face on the anode structural surface, and the second face 52 corresponds to the face on the cathode structural surface. When the spacer 5 includes two faces 51, 52 as shown in Figure 2 and Figure 3 , the spacer 5 then includes at least one distribution area 60, in this case the first distribution area 61 and the second distribution area 62, which is equivalent to Figure 2 the distribution area described in. Each distribution area 60 includes a distribution chamber 63 and a laminar flow device 64, which are respectively equivalent to Figure 2 the distribution chamber and the laminar flow member described in. Similar to the laminar flow member, the laminar flow device 64 extends along the longitudinal edge 17 of the recess 9 and includes a plurality of teeth 29 that define a channel 19, and the plurality of teeth 29 achieve a straight flow of the water flow so as to equalize the water flow. On the other hand, the distribution chamber 63 only includes a rectangular deflecting member 23, and the rectangular deflecting member 23 mainly extends in the flow direction of the water flow and is positioned near the inlet 25 or the outlet 26, and allows the water flow at the outlet of the inlet 25 or upstream of the outlet 26 to be equalized. Since the inlet 25 and the outlet 26 have smaller openings than the inlet 7 and the outlet 8, the second water flow circulating along the second face 52 is at a higher pressure than the first water flow circulating along the first face. Therefore, the higher pressure of the second water flow is sufficient to distribute water throughout the entire combination of the channels 19 of the laminar flow device 64 without the deflecting member 23 being required to ensure such distribution. The spacer 5 includes a sealing device 65 having the same function as the Figure 2 sealing member shown in. Different from the sealing member, the sealing device 65 particularly extends around the inlet 25 and the outlet 26 and does not include the inlet 7 and the outlet 8, such that the water flow circulating along the second face 52 circulates between the inlet 25 and the outlet 26, passes through one or more distribution areas 60 and circulates along the recess 9. In addition to the above and the features described with respect to Figure 3 , refer to Figure 2 for the description of the structural and functional features common to the two faces 51, 52 of the spacer 5.

[0051] Figure 4A cross-sectional view of the spacer is shown, more specifically a cross-sectional view of the first face 51 and the second face 52 at the level of the laminar member 14 and the laminar device 64. The sealing member 24 and the sealing device 65 are also partially visible. As previously mentioned, each of the laminar member 14 and the laminar device 64 includes teeth 29 that define the channel 19. In addition to the function of defining the channel 19, the teeth 29 also have mechanical resistance, allowing them to withstand the pressure 28 applied to the spacer, such as the first pressure 28a applied to the first face 51 and the second pressure 28b applied to the second face 52. The electrolytic cell is composed of a plurality of elements stacked and pressed against each other. Therefore, the support member 28 presses against the spacer, and the teeth 29 on each face 51, 52 of the spacer mechanically hold them. Thus, once the components of the electrolytic cell are stacked, the channel 19 is closed without being blocked, and water flow can occur. Although Figure 4 A support member applied to the laminar member 14 and the laminar device 64 is shown, but similar support members are also implemented in the distribution chamber and the distribution chamber. In such a configuration, it is the deflection member that provides mechanical resistance to maintain the water flow, regardless of the pressure applied by such a support member. Figure 5 A water electrolysis module 70 is shown, which includes a plurality of electrolytic cells 1 stacked one above the other in the stacking direction E, and the stacking direction E is perpendicular to the above-mentioned main plane. Therefore, the electrolysis module 70 includes as many electrolytic membranes, anodic compartments, and cathodic compartments as the electrolytic cells 1. The electrolysis module 70 includes a first inlet pipe 71 and a second inlet pipe 72. The first inlet pipe 71 is connected, for example, to the inlet of the spacer inside the reactor, and the second inlet pipe 72 is connected to the inlet of the spacer inside the reactor. The first inlet pipe 71 and the second inlet pipe 72 ensure the entry of water into the electrolysis module 70. More specifically, the first inlet pipe 71 allows water to enter and is configured to interact with the components of the anodic compartment of the electrolysis module 70, such as to cool them and / or supply the water electrolysis reaction. The second inlet pipe 72 allows the entry of water to be configured to interact with the components of the cathodic compartment of the electrolysis module 70, such as to cool them and / or supply the water electrolysis reaction. Therefore, each inlet pipe 71, 72 includes several outlet holes, and each outlet hole allows water to flow near the anodic compartment and the cathodic compartment according to the inlet pipes 71, 72 under discussion. The electrolysis module 70 also includes a first outlet pipe 73 and a second outlet pipe 74. The first outlet pipe 73 is connected to the outlet of the spacer inside the reactor, and the second outlet pipe 74 is connected to the discharge port of the spacer inside the reactor. The first outlet pipe 73 and the second outlet pipe 74 also mainly extend along the stacking direction E. The first outlet pipe 73 allows the collection of the two-phase water-oxygen mixture generated in the anodic compartment of the reactor after the water flow is close to the anodic catalyst layer of the electrolysis module 70.

[0052] The second outlet conduit 74 is used to collect the two-phase water-hydrogen mixture generated in the cathode compartment of the reactor after water has flowed close to the cathode catalyst layer of the electrolysis module 70.

[0053] To ensure that the electrolytic cells 1 are stacked and sealed within the electrolysis module 70, the latter further includes a plurality of attachment devices 75 which allow the electrolytic cells 1 to be pressed against one another in the stacking direction E.

[0054] Of course, the present invention is not limited to the examples just described, and many adjustments can be made to these examples without departing from the scope of the present invention.

[0055] As just described, the present invention achieves its intended purpose and allows for the provision of a spacer for an electrolytic cell which ensures uniform fluid distribution over the components of said electrolytic cell. Variations not described herein can be implemented without departing from the context of the present invention, provided that, according to the present invention, they include a spacer according to the present invention.

Claims

1. A spacer (5) for a water electrolysis cell (1), the spacer (5) being configured to support a separator (2), the spacer (5) comprising at least one inlet (7) and an outlet (8) configured to allow water to flow within the water electrolysis cell (1), the spacer (5) comprising a recess (9) configured to be occupied by the separator (2) and in fluid communication with the inlet (7) and the outlet (8), the spacer (5) further comprising at least one distribution area (10) connecting the inlet (7) or the outlet (8) to the recess (9), characterized in that, The distribution area (10) includes at least one laminar member (14) extending along the edges (17, 18) of the recess (9).

2. The spacer (5) according to claim 1, wherein, The laminar member (14) includes a plurality of teeth (29) spaced apart to form channels (19) configured to enable a straight flow of water.

3. The spacer (5) according to claim 1, wherein, The teeth (29) of the laminar member (14) are configured to provide resistance against the support member (28) at the level of the laminar member (14).

4. The spacer (5) according to any one of the preceding claims, wherein, The distribution area (10) includes a distribution chamber (20) extending between the inlet (7) or the outlet (8) and the laminar member (14).

5. The spacer (5) according to the preceding claim, wherein, The distribution chamber (20) includes a plurality of deflection members (23).

6. The spacer (5) according to the preceding claim, wherein, The plurality of deflection members (23) are configured to provide resistance against the support member (28) at the level of the distribution chamber (20).

7. The spacer (5) according to claim 5 or 6, wherein At least one deflection member (23) is oblong.

8. The spacer (5) according to any one of the preceding claims, wherein, The recess (9) is rectangular in shape and has two longitudinal edges (17) and two transverse edges (18), and the laminar member (14) is arranged along one of the longitudinal edges (17).

9. The spacer (5) according to the previous claim, wherein, The inlet (7) and the outlet (8) are located between two straight lines (Z1, Z2) passing through the transverse edge (18).

10. The spacer (5) according to any one of the preceding claims, wherein, The inlet (7) and the outlet (8) are symmetrically arranged with respect to the center point (Y) of the spacer (5).

11. The spacer (5) according to any one of the preceding claims, wherein, The distribution area (10) is a first distribution area (11), and the spacer (5) includes a second distribution area (12) at least partially symmetric with respect to the central axis (13) of the recess (9) relative to the first distribution area (11).

12. The spacer (5) according to any one of the preceding claims, including a first face (51) and a second face (52), the spacer (5) including an inlet (25) and an outlet (26) configured to allow water to flow through the electrolytic water cell (1), the spacer (5) further including at least one distribution area (60) connecting the inlet (25) or the outlet (26) to the recess (9), the distribution area (10) being formed in the thickness of the spacer (5) by leading to the first face (51), while the distribution area (60) is formed in the thickness of the spacer (5) by leading to the second face (52).

13. The spacer (5) according to the previous claim, wherein, The distribution area (60) includes at least one laminar device (64) extending along the edges (17, 18) of the recess (9).

14. An electrolytic water cell (1) includes an anode (3), a cathode (4), and a separator (2) between the anode (3) and the cathode (4), the electrolytic water cell (1) including the spacer (5) according to any one of the preceding claims, the spacer (5) supporting the anode (3), the cathode (4), and the separator (2).

15. A water electrolysis module (70) comprising a plurality of electrolytic cells (1) according to the preceding claims, said electrolytic cells (1) being stacked one on top of the other.

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