Separator plate, bipolar plate, production method and electrochemical cell
Patent Information
- Application Number
- EP2024703473
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-02-28
- Filing Date
- 2024-01-24
- Publication Date
- 2026-01-07
AI Technical Summary
The existing injection molding process for producing sealing arrangements on thin metallic separator and bipolar plates in electrochemical cells often results in deformation due to contact pressure, leading to inconsistent sealing geometry and reduced volume for injection molding material, which affects the dimensional accuracy and thickness of the sealing arrangement.
Incorporating three-dimensional support structures within the half-sheets, such as conical or hemispherical shapes, that protrude from the plane and are aligned to counteract deformation, allowing the injection molding material to embed and stabilize the plates, thus maintaining desired dimensions and preventing warping during the molding process.
The support structures significantly reduce deformation, ensure precise molding of the sealing arrangement with consistent geometry, and enable the injection of the required amount of material, resulting in a detailed and accurately shaped sealing arrangement on the plates.
Smart Images
Figure DE2024100052_06092024_PF_FP
Abstract
Description
[0001] Separator plate, bipolar plate, process and electrochemical cell
[0002] The invention relates to a separator plate comprising a half-sheet with an active field, a frame arrangement surrounding the active field, and a sealing arrangement associated with the frame arrangement, which comprises a seal that runs in a wave-like manner in plan view of a plane spanned by the separator plate. The invention further relates to a bipolar plate comprising a first half-sheet and a second half-sheet, each with an active field, a frame arrangement surrounding the active field, and a sealing arrangement associated with the frame arrangement, which comprises a seal that runs in a wave-like manner in plan view of a plane spanned by the bipolar plate. The invention further relates to a method for producing sealing arrangements on a separator plate or a bipolar plate. Finally, the invention relates to an electrochemical cell.
[0003] A separator plate or bipolar plate of the type mentioned above and an electrochemical cell in the form of a fuel cell are known from DE 102021 115 559 A1. The separator plate or bipolar plate has a sealing arrangement running along the edge of the bipolar plate and surrounding the supply and discharge channels for fluids of the bipolar plate, referred to here as ports, which is intended to seal the active field of the separator plate or bipolar plate from the environment. The sealing arrangement comprises a wave-shaped seal and is made of plastic. The permanent application of the sealing arrangement to the respective half-sheet of the separator plate or bipolar plate is carried out using an injection molding process. The separator plate or bipolar plate is inserted into an injection molding tool, and the tool is closed.The use of the injection molding process enables high dimensional accuracy and repeatability in the production of the sealing arrangement, since the geometry of the sealing arrangement is generally designed depending on the injection molding tool used. However, it has been shown that when the injection mold is closed, contact pressure of the sealing edges of the tool on the surfaces of a thin-walled separator plate comprising a half-sheet or a bipolar plate comprising two firmly connected half-sheets can cause the half-sheets to deform in the form of a bulge within the resulting cavity to be filled with injection molding material. Cavities are formed on both sides of the separator plate or bipolar plate, since sealing assemblies usually have to be formed on both sides.
[0004] Metallic separator plates or bipolar plates typically have half-sheet thicknesses in the range of less than 0.5 mm. With such thin sheet thicknesses, residual compressive stresses quickly lead to undesirable deformations in the surrounding areas. The effect is greater the lower the sheet thickness of the half-sheets used. In this case, the cavity of the injection mold is slightly reduced at least on one side of the separator plate, but in the case of a bipolar plate possibly also the cavities on both sides of the bipolar plate, and the volume for injecting the injection molding material is thus reduced. If the injection molding compound is now injected into the injection molding tool, the intended amount of injection molding material to form a sealing arrangement with the desired geometric dimensions cannot be introduced, at least on one side of the plate.
[0005] After the injection molding material has hardened and the injection molding tool is opened, the previously deformed area(s) of the at least one half-sheet springs back to its original position. Because the injection molding material cannot be injected into the cavity of the injection molding tool, the seal arrangement no longer has the required geometry or thickness on the at least one half-sheet or both half-sheets. Following demolding and at least partial recurving of one or both half-sheets, the seal height therefore deviates from the tool dimension. This deviation is particularly pronounced in straight sealing areas. The bulging effect also varies in intensity depending on the sheet rolling direction, the surrounding embossing geometry, radii, or a curved sealing bead.The object of the invention is to provide a separator plate comprising a half-sheet or a bipolar plate comprising a first half-sheet and a second half-sheet, which has a correctly and reproducibly dimensioned sealing arrangement that is injection-molded onto the separator plate or bipolar plate. Furthermore, the object of the invention is to provide a suitable method for this purpose and to provide an electrochemical cell.
[0006] The object is achieved for the separator plate comprising a half-sheet metal with an active field, a frame arrangement surrounding the active field, and a sealing arrangement which is to be attributed to the frame arrangement and which comprises a seal which runs in a wave-like manner in a plan view of a plane spanned by the separator plate, in that a three-dimensional support structure is formed in the half-sheet metal in the region of the sealing arrangement, wherein the support structure is designed to protrude from the plane spanned by the separator plate.
[0007] The object is achieved for the bipolar plate, comprising a first half-sheet and a second half-sheet, each with an active field, a frame arrangement surrounding the active field, and a sealing arrangement which is to be assigned to the frame arrangement and which comprises a seal which runs in a wave-like manner in a plan view of a plane spanned by the bipolar plate, in that a three-dimensional support structure is formed in the two half-sheets in the region of the sealing arrangement, wherein the support structures of the two half-sheets are designed to protrude in opposite directions from the plane spanned by the bipolar plate and to be aligned one above the other when viewed perpendicular to the plane.
[0008] In the active field area of a separator plate or bipolar plate, electrochemical reactions take place in an electrochemical cell, with fluids supplied to the cell undergoing chemical conversion. By providing support structures in each half-sheet within the geometry of the seal assembly, the deformation of the half-sheet or half-sheets in the injection molding tool can be significantly reduced, as this results in local stiffening of the half-sheet, which counteracts the deformation. The injection molding material flows around the support structure, embeds it, and provides additional mechanical stabilization of the separator plate or bipolar plate.
[0009] The support structures preferably have a conical, hemispherical, or lens-like shape when viewed in cross-section through the separator plate or bipolar plate. Such support structures in the half-sheet or the two half-sheets provide excellent local stiffening of the half-sheet. In a bipolar plate, the support structures can be aligned particularly well in alignment with one another.
[0010] It has proven particularly effective to have the three-dimensional support structure molded into the half-sheet metal in the area of the wave-shaped seal, with one support structure formed in the half-sheet metal for each wave structure of the wave-shaped seal. However, multiple support structures can also be provided per wave structure to further increase the stiffening of the half-sheet metal in this area.
[0011] The wave-shaped seal preferably has a plurality of straight sections which define a common first straight line, wherein the straight sections are each connected to one another by curved sections. The maximum offset of each curved section, measured orthogonally to the said first straight line, relative to the straight sections of the seal corresponds, for example, to at least twice and at most five times the width of the wave-shaped seal. The running length of the wave-shaped seal is thus significantly increased compared to a conceivable straight sealing strip, without requiring excessive additional installation space. In this embodiment, the minimum radius of curvature of the wave-shaped seal can, in particular, be greater than the width of the wave-shaped seal, but smaller than the said offset between the curved sections and the straight sections of the wave-shaped seal.In particular, the minimum radius of curvature is given at the transitions between a straight section and a curved section of the wave-shaped seal.
[0012] Preferably, each of the support structures is arranged on a straight line that intersects the straight section of the associated wave structure centrally and at a 90° angle. A wave structure comprises a straight section and two adjacent curved sections.
[0013] Preferably, the support structure in each half-sheet has a height starting from a surface of the half-sheet that corresponds to a maximum thickness D ± 20% of the sealing arrangement molded onto the half-sheet. The height of the support structure is therefore designed such that it has a slight undersize (-20%) to a slight oversize (+20%) relative to a cavity height of an injection molding tool for forming the sealing arrangement, and the support structure can thus be supported on the interior of the injection molding tool. When the injection molding tool is closed, the support structures inside the cavity formed between the surface of the separator plate or bipolar plate and the injection molding tool touch the injection molding tool. The half-sheet(s) are thus held in the desired position and directly counteract any undesired deformation of the half-sheet(s).
[0014] Such support structures can be used in a main or secondary sealing section of the sealing arrangement. The term "secondary sealing section" refers, in particular, to sealing sections that serve to contain flow bypasses adjacent to the active field, such as the wave-shaped seal of the sealing arrangement here. The separator plate is constructed from a profiled half-sheet or sheet metal and has embossed flow channels on the anode and cathode sides for conducting fluids. These channels are preferably aligned parallel to the straight sections of the wave-shaped seal, particularly in the active field.
[0015] The bipolar plate is constructed, in particular, from two profiled half-sheets and has embossed flow channels on the anode and cathode sides for conducting fluids. These channels are preferably aligned parallel to the straight sections of the wave-shaped seal, particularly in the active field. The half-sheets are connected to each other in a material-to-material manner, for example, by welds. Gluing or soldering the two half-sheets together is also possible. A space through which a coolant can flow is preferably formed between the profiled half-sheets.
[0016] A half sheet of a separator plate or a bipolar plate preferably has sheet thicknesses in the range of 50 to 200 pm, in particular in the range of 50 to 100 pm.
[0017] The separator plate or bipolar plate according to the invention is suitable for forming an electrochemical cell, in particular in the form of a polymer electrolyte fuel cell or a polymer electrolyte electrolyzer for the electrolysis of water or a redox flow cell.
[0018] The object is achieved for the method for producing sealing arrangements on a separator plate according to the invention or a bipolar plate according to the invention with the following steps:
[0019] - Inserting the half-sheet or two half-sheets firmly connected to each other into an injection molding tool, whereby a cavity is formed for forming a sealing arrangement between the half-sheet and the injection molding tool, whereby the three-dimensional support structure is supported in the cavity against the injection molding tool,
[0020] - Injecting injection molding material into the cavity with at least partial embedding of the support structure in the injection molding material,
[0021] - Curing of the injection molding material in the cavity and
[0022] - Demoulding the separator plate or bipolar plate with the sealing arrangement(s) molded onto it.
[0023] The support structure therefore acts as a spacer between the respective half-sheet and the injection mold, preventing warping of the half-sheet or half-sheets when the injection mold closes. Furthermore, the support structure is embedded in the sealing arrangement, whereby only those areas of the support structure that are in contact with the injection mold during the injection process can remain uncovered by injection molding material. The support structures do not impair the sealing function of the sealing arrangement. Rather, the support structures lead to greater dimensional accuracy of the sealing arrangement and enable more precise molding of the cavity of the injection mold with injection molding material. The result is a detailed and precisely formed sealing arrangement, molded onto one or both sides of a half-sheet of a separator plate, or molded onto each of the half-sheets of a bipolar plate.
[0024] The object is achieved for the electrochemical cell comprising a plurality of separator plates according to the invention or bipolar plates according to the invention and at least one membrane-electrode arrangement arranged between two separator plates or bipolar plates, which has a central region adjacent to an active field and a region arranged outside the active field as seen perpendicular to the plane spanned by the separator plate or bipolar plate, wherein the undulating seal is located at the boundary between said regions. The membrane-electrode arrangement can, for example, have a seven-layer structure and generally comprises a membrane, electrode layers applied to both sides of the membrane to form an anode and a cathode, catalyst layers applied to both sides, and optionally porous fluid distribution layers arranged on both sides.The membrane-electrode assembly often has a rigidly bonded plastic support frame for reinforcement at the edge. The electrode layers, catalyst layers, and fluid distribution layers are then located within the plastic support frame, which encloses the respective active field of the separator plates or bipolar plates adjacent to the membrane-electrode assembly and often provides a contact surface for the sealing assembly on the adjacent separator plate or bipolar plate. The membrane itself is preferably a polymer electrolyte membrane or a polymer ion exchange membrane, depending on the type of electrochemical cell.
[0025] Directly adjacent to the wave-shaped seal of the sealing arrangement, there is preferably a bypass channel for a fluid flowing through the electrochemical cell. Such a bypass channel can be created, in particular, by pressing together components of the membrane-electrode assembly and the frame assembly of the separator plate or bipolar plate during assembly. The shape of the bypass channel follows the course of the wave-shaped seal.
[0026] The electrochemical cell is preferably a polymer electrolyte fuel cell or a polymer electrolyte electrolyzer for water electrolysis, or a redox flow cell. Such a fuel cell is suitable for both stationary and mobile applications, particularly in motor vehicles.
[0027] An embodiment of the invention is explained in more detail below with reference to the accompanying figures. Fig. 1 shows a separator plate or bipolar plate in a schematic plan view.
[0028] Fig. 2 shows an enlarged section of the separator plate or bipolar plate according to Figure 1 (marked with a circle there) in perspective view,
[0029] Fig. 3 the section according to Figure 2 without sealing arrangement in perspective view,
[0030] Fig. 4 shows the section from Figure 1 in a further enlarged view,
[0031] Fig. 5 and 6 a section through a bipolar plate and a membrane electrode arrangement adjacent to it on one side in the area of the sealing arrangement,
[0032] Fig. 7a shows a section through an injection moulding tool with a clamped half sheet according to the state of the art,
[0033] Fig. 7b shows in section an injection molding tool with a clamped half-sheet having a support structure in the area of the sealing arrangement to be formed,
[0034] Fig. 8a shows a section through an injection molding tool with a clamped bipolar plate comprising two half sheets according to the prior art,
[0035] Fig. 8b shows in section an injection molding tool with a clamped bipolar plate comprising two half sheets each having a support structure in the area of the sealing arrangements to be formed,
[0036] Fig. 9 is a perspective view of a schematically illustrated bipolar plate, and
[0037] Fig. 10 is a perspective view of an electrochemical cell in a cell stack.
[0038] Figure 1 shows a separator plate 28 or a bipolar plate 1 in a schematic plan view. The separator plate 28 or bipolar plate 1 has an active field 2 and a frame arrangement 11 surrounding the active field 2. Also included in the frame arrangement 11 is a sealing arrangement 15, which comprises a seal 16 that runs in a wave-like manner in a plan view of a plane (xy plane) spanned by the separator plate 28. A three-dimensional support structure 29 is formed in the half-sheet metal 3 in the region of the sealing arrangement 15, wherein the support structure 29 is designed to protrude from the xy plane spanned by the separator plate 28 or bipolar plate 1 in the direction of the observer.
[0039] For the flow guidance of fluids such as hydrogen, air, coolant and the like, as well as for the discharge of fluids, three fluid passage openings 5, 6, 7 are formed through the separator plate 28 or bipolar plate 1 on one side of the active field 2 and three further fluid passage openings 8, 9, 10 are formed on the opposite side of the active field 2.
[0040] Figure 2 shows an enlarged section of the separator plate 28 or bipolar plate 1 according to Figure 1 in a perspective view. The same reference numerals as in Figure 1 denote the same elements. The sealing arrangement 15 with the wave-shaped seal 16 on a half-sheet metal 3 can now be seen, as well as support structures 29 molded into this in the region of the wave-shaped seal 16. Furthermore, the active field 2 with its molded-in fluid channels 21 and a bypass channel 25 adjacent to the wave-shaped seal 16 can be seen. In this section, the wave-shaped seal 16 has four wave structures, each with a support structure 29 arranged centrally in the wave structure.
[0041] Figure 3 shows the section according to Figure 2 without the sealing arrangement 15 in a perspective view. The same reference numerals as in Figures 1 and 2 identify the same elements. The conical shape of three support structures 29 protruding from the half-sheet 3 can now be clearly seen.
[0042] Figure 4 shows the section from Figure 1 in a further enlarged view.
[0043] The same reference numerals as in Figures 1 to 3 indicate the same elements.
[0044] The sealing arrangement 15 has a strip structure 17, with the wave-shaped seal 16 representing the innermost strip of the strip structure 17. In contrast to the strips further outward of the strip structure 17, the wave-shaped seal 16 describes alternating straight sections 23 and curved sections 24, which approximately have the shape of a half sine wave. The width of the wave-shaped seal 16, visible in the plan view, is designated BD. Immediately next to the wave-shaped seal 16, in the direction of the active field 2, the bypass channel 25 can be seen, which follows the course of the wave-shaped seal 16 and has a bypass channel width BB. In the case of the bypass channel 25, straight sections are designated 26 and curved sections 27. The maximum distance of the curved sections 24 from the straight sections 23, measured orthogonally to the straight sections 23 of the wave-shaped seal 16, is called the maximum offset V mand represents the amplitude of the wave-shaped seal 16, which is deflected in the form of half-waves. The minimum radius of the wave-shaped seal 16, designated MD, can be found at the transitions between the straight sections 23 and the curved sections 24. The minimum radius of curvature MD of the wave-shaped seal 16 is greater than its width BD, but smaller than the aforementioned offset V m .
[0045] Figures 5 and 6 each show a section through a bipolar plate 1 and a membrane-electrode assembly 12 adjacent to it on one side in the region of the sealing assembly 15. The bipolar plate 1 has two half-sheets 3, 4 welded together. On the surface of the bipolar plate 1 facing the membrane-electrode assembly 12, a sealing assembly 15 is injection-molded onto the half-sheet 3, which comprises a wave-shaped seal 16. On the surface of the bipolar plate 1 facing away from the membrane-electrode assembly 12, a sealing assembly 15' is injection-molded onto the half-sheet 4, which comprises a wave-shaped seal 16'. In Figure 5, the course of the sealing assembly 15 below the membrane-electrode assembly 12 is indicated by dashed lines. Coolant channels 20 are formed between the two half-sheets 3, 4 in the region of the active field 2.Between the membrane-electrode assembly 12 and the bipolar plate 1, fluid channels 21 are provided in the area of the active field 2. On the side of the bipolar plate 1 facing away from the membrane-electrode assembly 12, further fluid channels 22 are provided in the area of the active field 2. A central region of the membrane-electrode assembly 12, designated 13, which is located largely above the active field 2, is to be distinguished from an outer region 14 of the membrane-electrode assembly 12, which rests on the frame assembly 11 and partially protrudes beyond it.
[0046] If in the present case it is mentioned that one component rests on another component, this refers to the arrangement visible in the figures and does not contain any statement about the spatial orientation of the components during normal operation.
[0047] Fig. 7a shows a section through an injection molding tool comprising an upper part 18 and a lower part 19 with a half-sheet metal 3 clamped between them according to the prior art. A cavity K1 is formed between the half-sheet metal 3 and the upper part 18 of the injection molding tool. A cavity K2 is formed between the half-sheet metal 3 and the lower part 19 of the injection molding tool. Due to the clamping forces of the upper part 18 against the lower part 19, the thin half-sheet metal 3 bulges in the direction of the cavity K1, so that the cavity K1 is smaller than the cavity K2. When injection molding material 30 is injected into the cavities K1, K2, less injection molding material 30 is introduced into the region of the cavity K1 than into the cavity K2. After the injection molding material 30 has hardened and the injection molding tool has been opened, the half-sheet metal 3 returns to its originally flat shape.The sealing arrangement 15 formed between the upper part 18 of the injection molding tool and the half-sheet 3 is now thinner than required, while the sealing arrangement 15' formed between the lower part 19 of the injection molding tool and the half-sheet 3 is thicker than required.
[0048] Fig. 7b shows a cross-sectional view of an injection molding tool with a clamped half-sheet metal 3 having a support structure 29 in the region of the sealing assemblies 15, 15' to be formed. The same reference numerals as in Fig. 7a identify the same elements. The support structure 29 stiffens the half-sheet metal 3 and is supported on the upper part 18 of the injection molding tool. This prevents undesired deformation of the half-sheet metal 3. When injection molding material 30 is injected into the cavities K1, K2, the cavities K1, K2 fill with the desired amount of injection molding material. After the injection molding material 30 has hardened and the injection molding tool has been opened, the sealing assembly 15 formed between the upper part 18 of the injection molding tool and the half-sheet metal 3, as well as the sealing assembly 15' formed between the lower part 19 of the injection molding tool and the half-sheet metal 3, have the required dimensions.
[0049] Fig. 8a shows a section through an injection molding tool with a clamped bipolar plate 1 comprising two half-sheets 3, 4 according to the prior art. The same reference numerals as in Figure 7a identify the same elements. A cavity K1 is formed between the half-sheet 3 and the upper part 18 of the injection molding tool. A cavity K2 is formed between the half-sheet 4 and the lower part 19 of the injection molding tool. Due to the clamping forces of the upper part 18 against the lower part 19, the thin half-sheets 3, 4 bulge in the direction of the cavities K1, K2, so that the cavities K1, K2 become smaller. When injection molding material 30 is injected into the cavities K1, K2, less injection molding material 30 than required is introduced into the area of the cavities K1, K2. After the injection molding material 30 has hardened and the injection molding tool has been opened, the half sheets 3, 4 return to their original flat shape.The sealing arrangement 15 formed between the upper part 18 of the injection molding tool and the half-sheet 3 and also the sealing arrangement 15' formed between the lower part 19 of the injection molding tool and the half-sheet 4 are thinner than required.
[0050] Fig. 8b shows a section through an injection molding tool with a clamped bipolar plate 1 comprising two half-sheets 3, 4, each having a support structure 29 in the region of the sealing arrangements 15, 15' to be formed. The same reference numerals as in Fig. 7b identify the same elements. The support structures 29 stiffen the half-sheets 3, 4 and are supported on the upper part 18 of the injection molding tool in the case of half-sheet 3 and on the lower part 19 of the injection molding tool in the case of half-sheet 4. This prevents undesired deformation of the half-sheets 3, 4. When injection molding material 30 is injected into the cavities K1, K2, the cavities K1, K2 fill with the desired amount of injection molding material.After curing of the injection molding material 30 and opening of the injection molding tool, the sealing arrangement 15 formed between the upper part 18 of the injection molding tool and the half-sheet 3 as well as the sealing arrangement 15' formed between the lower part 19 of the injection molding tool and the half-sheet 4 are present in the required dimensions.
[0051] Fig. 9 shows a perspective view of a schematically illustrated bipolar plate 1. The same reference numerals as in Figure 1 identify the same elements.
[0052] Fig. 10 shows a perspective view of an electrochemical cell 40 in a cell stack 50 comprising a multiplicity of electrochemical cells 40. The electrochemical cell 40 comprises a plurality of bipolar plates 1, 1' and at least one membrane-electrode arrangement 12, 12' arranged between two bipolar plates 1, 1', which has a central region 13 adjacent to the active field 2 and a region 14 arranged outside the active field 2 as seen perpendicular to the plane spanned by the bipolar plate 1, wherein the wave-shaped seal 16 is located at the boundary between the said regions 13, 14, see also Figure 6.
[0053] Overall, the described design of the sealing arrangement 15 contributes significantly to a uniform flow through the active field 2 with a good sealing effect and space-saving stacking of the bipolar plates 1, 1'. List of reference symbols, r Bipolar plate
[0054] Active field
[0055] Half sheet
[0056] Half sheet
[0057] Fluid passage opening
[0058] Fluid passage opening
[0059] Fluid passage opening
[0060] Fluid passage opening
[0061] Fluid passage opening 0 Fluid passage opening 1 Frame assembly 2, 12' Membrane electrode assembly 3 Central region of the membrane electrode assembly 4 Outer region of the membrane electrode assembly 5, 15' Seal assembly 6, 16' Wave-shaped seal 7 Strip structure 8 Injection mold, upper part 9 Injection mold, lower part 0 Coolant channel 1 Fluid channel 2 Fluid channel 3 Straight section of the wave-shaped seal 4 Curved section 5 Bypass channel 6 Straight section 7 Curved section 8 Separator plate 9 Support structure 0 Injection molding material 40 Electrochemical cell
[0062] 50 cell stacks
[0063] BB Bypass channel width
[0064] BD Width of the wave-shaped seal
[0065] MD minimum radius of the wave-shaped seal
[0066] V m maximum offset
[0067] K1, K2 cavity
Claims
Patent claims 1. Separator plate (28), comprising a half-sheet metal part (3, 4) with an active field (2), a frame arrangement (11) surrounding the active field (2), and a sealing arrangement (15, 15') which is assigned to the frame arrangement (11) and which comprises a seal (16, 16') which, in a plan view onto a plane spanned by the separator plate (28), runs in a wave-shaped manner, characterized in that a three-dimensional support structure (29) is formed in the half-sheet metal part (3, 4) in the region of the sealing arrangement (15, 15'), the support structure (29) being designed to protrude from the plane spanned by the separator plate (28).
2. Bipolar plate (1), comprising a first half-sheet (3) and a second half-sheet (4), each with an active field (2), a frame arrangement (11) surrounding the active field (2), and a sealing arrangement (15, 15') which is assigned to the frame arrangement (11) and which comprises a seal (16, 16') which, in a plan view onto a plane spanned by the bipolar plate (1), runs in a wave-shaped manner, characterized in that a three-dimensional support structure (29) is formed in the two half-sheets (3, 4) in the region of the sealing arrangement (15, 15'), the support structures (29) of the two half-sheets (3, 4) projecting in opposite directions from the plane spanned by the bipolar plate (1) and being aligned one above the other when viewed perpendicular to the plane.
3. Separator plate (28) or bipolar plate (1) according to claim 1 or 2, characterized in that the support structure (29) has a conical or hemispherical or lens-like shape when viewed in cross section through the separator plate (28) or the bipolar plate (1).
4. Separator plate (28) or bipolar plate (1) according to one of claims 1 to 3, characterized in that the support structure (29) in the region of the wave- shaped seal (16, 16') is formed into the half-sheet metal (3, 4) and for each wave structure of the wave-shaped seal (16, 16') a support structure (29) is formed in the half-sheet metal (3, 4).
5. Separator plate (28) or bipolar plate (1) according to one of claims 1 to 4, characterized in that the wave-shaped seal (16, 16') has a plurality of straight sections (23) by which a common straight line is defined, wherein the straight sections (23) are each connected to one another by curved sections (24).
6. Separator plate (28) or bipolar plate (1) according to claim 5, characterized in that each of the support structures (29) is arranged on a straight line which intersects the straight section (23) of the associated wave structure centrally and at a 90° angle.
7. Separator plate (28) or bipolar plate (1) according to one of claims 1 to 6, characterized in that the support structure (29) in the half-sheet (3, 4) has a height starting from a surface of the half-sheet (3, 4) which corresponds to a maximum thickness D ± 20% of the sealing arrangement (15, 15') injection-molded onto the half-sheet (3, 4) on this surface.
8. Method for producing sealing arrangements (15, 15') on a separator plate (28) or a bipolar plate (1) according to one of claims 1 to 7, with the following steps: - inserting the half-sheet (3, 4) or two half-sheets (3, 4) firmly connected to one another into an injection-molding tool (18, 19), whereby a cavity (K1, K2) for forming a sealing arrangement (15, 15') is formed between the half-sheet (3, 4) and the injection-molding tool (18, 19), whereby the three-dimensional support structure (29) is supported in the cavity (K1, K2) against the injection-molding tool (18, 19), - injecting injection molding material (30) into the cavity (K1, K2) with at least partial embedding of the support structure (29) in the injection molding material (30), - Curing of the injection molding material (30) in the cavity (K1, K2) and - demoulding the separator plate (28) or bipolar plate (1) with the sealing arrangement(s) (15, 15') formed thereon.
9. An electrochemical cell (40) comprising a plurality of separator plates (28) or bipolar plates (1, 1') according to any one of claims 1 to 7 and at least one membrane electrode assembly (12, 12') arranged between two separator plates (28) or bipolar plates (1, 1'), said assembly having a central region (13) adjacent to an active field (2) and a region (14) arranged outside the active field (2) as seen perpendicular to the plane spanned by the separator plate (28) or the bipolar plate (1), wherein the wave-shaped seal (16, 16') is located at the boundary between said regions (13, 14).
10. Electrochemical cell (40) according to claim 9, characterized in that it is a polymer electrolyte fuel cell or a polymer electrolyte electrolyzer for the electrolysis of water or a redox flow cell.