Plate assembly for electrochemical cells

Abstract

An electrochemical cell (1), in particular a plate assembly (2) for a fuel cell, comprising a grid formed as expanded metal (3) provided for sandwich-like arrangement between a first plate (5) located in a base plane and a second plate (4) parallel to the first plate (5), the grid having a plurality of nodules (6) and webs (10, 11) connecting the nodules (6), wherein nodule rows (KR1, KR2) defining a longitudinal direction (LR) are formed, which extend parallel to each other in a plan view of the grid (3) from above, and all nodules (6) have a planar, bent shape with a fold line oriented transversely to the longitudinal direction (LR) separating two nodule sections (7, 8) from each other. A plate assembly (2) wherein in at least a subset of the nodules (6), each one of the nodule sections (7) is arranged at least substantially parallel to the above-mentioned plates (4, 5).

Description

Technical Field

[0001] The present invention relates to a plate assembly including a grid formed as expanded metal, which is defined for use in an electrochemical cell, particularly a fuel cell, as described in the preamble of claim 1.

Background Art

[0002] Such a plate assembly of an electrochemical cell is known, for example, from German Patent Invention No. 112009004658. This known plate assembly is defined for use in a fuel cell and includes a so-called gas passage forming element, which exists in the form of an expanded metal grid. The connecting sections of the expanded metal, i.e., the nodes, have distinguishable sections, and these sections are inclined with respect to a plate, particularly in the form of a separator, in which the expanded metal is inserted, in different forms. An acute angle may particularly be formed between the node section and the plate. The angle formed between one section of the node and the separator is smaller than the angle formed between another section of the node and the gas diffusion layer. German Patent Invention No. 112009004658 defines the production of expanded metal from titanium.

[0003] DE11200700017T5 is directed to a method for forming a gas diffusion layer for a fuel cell. Within the framework of this method, a metal grid processing device for processing a special steel thin plate is used. The special steel thin plate can be supplied to a holding mechanism using supply rollers. Similarly, through holes are formed in a lattice-like offset arrangement by a cutting tool belonging to the metal grid processing device. These through holes have a hexagonal shape and provide a free cross-section when the grid is incorporated into a fuel cell.

[0004] The separator for a fuel cell described in U.S. Patent No. 8,206,865 is connected by a current collector formed from a metal grid. The possibility of stacking multiple metal grids to form the current collector is also mentioned. The contact area between the current collector and the electrode layer is preferably greater than or equal to the contact area between the current collector and the separator body.

[0005] Another element for forming gas channels within a fuel cell battery is disclosed in U.S. Patent No. 9,160026. In this case as well, the element forming the gas channels is provided in the form of a metal grid structure. The element described above has a plurality of annular sections that form through-openings.

[0006] U.S. Patent No. 9450253 describes possible geometric details of a cell structure for a fuel cell, formed from expanded metal. In this case, the expanded metal mesh exhibits a hexagonal or other polygonal shape. [Overview of the project] [Problems that the invention aims to solve]

[0007] The fundamental problem of this invention is to improve upon the above-mentioned prior art in terms of elements for electrochemical cells, particularly fuel cells, especially from a flow technology and manufacturing technology standpoint, and to aim for a robust structure suitable for mobile applications of the final product in the form of a fuel cell stack, i.e., a fuel cell system or other electrochemical system. [Means for solving the problem]

[0008] This problem is solved, according to the present invention, by a plate assembly suitable for use in an electrochemical cell having the features described in claim 1. The plate assembly is suitable for forming a stack of electrochemical cells as described in claim 10.

[0009] The plate assembly, in a basic concept known to the extent, is a grid formed as expanded metal, provided to be sandwiched between a first plate located on a base plane and a second plate parallel to the first plate, and includes a grid having a plurality of knots and webs connecting the knots, wherein rows of knots defining the longitudinal direction are formed, extending parallel to each other in a plan view of the grid from above, and all knots have a planar folded shape with a fold line oriented laterally to the longitudinal direction that separates the two knot divisions of each knot from each other.

[0010] According to claim 1, in at least one subset of the nodal portions (Teilmenge), one nodal portion of each of the two nodal portions is positioned at least substantially parallel to the plate described above. In this case, substantially parallel positioning means that the nodal portion in question forms an angle of 15° or less with an adjacent plate of the electrochemical system. In particular, the nodal portion in question is placed flat on the plate described above, which may be formed by a membrane electrode assembly.

[0011] This shape of the expanded metal equally satisfies multiple functions of the plate assembly. On the one hand, the numerous knot sections of the expanded metal, at least substantially parallel to the plates, provide a large, dimensioned contact area overall. This contact area absorbs forces within the plate stack with moderate surface pressure and conducts current. On the other hand, the inclined plate sections, together with the grid, or web, of the expanded metal, provide an intentional flow-guiding effect, so that the medium flowing between the plates acquires a flow component perpendicular to the plates.

[0012] Each nodal section, which is positioned parallel to the plate or merely slightly inclined to the plate, i.e., at an angle of less than 15°, is connected via two webs to a nodal section that is inclined to a greater degree with respect to the plate defining the base plane, i.e., forming a larger angle with the plate, unless this nodal section is positioned at the edge of the grid. This means that the webs themselves are twisted. This contributes to both flow guidance and the mechanical stability of the expanded metal.

[0013] In one possible configuration, in several nodal sections of the expanded metal, particularly in nodal sections arranged in a specific row, a first nodal section is planarly resting on a base plane which may be created by the film electrode assembly, whereas in another nodal section, typically arranged in a row, there is a gap between the nodal section and the aforementioned plane, and the first nodal section is positioned in a plane parallel to the base plane. In this configuration, while there is indeed a smaller overall contact area between the nodal section and one of the plates fitted to the expanded metal compared to embodiments where the first nodal section of each nodal section is in contact with the base plane, there is an expanded free cross-section for the medium flowing through the plate assembly, precisely based on the nodal section lifted from the base plane.

[0014] The knots placed on the base plane and the knots lifted from the base plane may be arranged alternately in each row of knots extending in the longitudinal direction of the expanded metal. Similarly, it is also possible to realize a modified expanded metal in which, for example, two rows of knots that are always arranged side by side are placed on the base plane, and a third row of knots is lifted from the base plane.

[0015] Initially, when manufacturing expanded metal from a metal sheet without openings, the process can be carried out using a variable feed rate of the metal sheet. This feed rate is reflected in the finished product, i.e., the expanded metal, in that it results in knot sections of varying lengths. The length can be measured in the feed direction, which is perpendicular to the broken line forming the boundary between the two knot sections. In each knot section, its length is measured on the surface of that section, not on the projection of the knot onto the base plane.

[0016] The variable feed rate applied to the metal sheet to be processed into expanded metal allows for the formation of four different types of knots within a single, identical grid existing in the form of expanded metal, in a single manufacturing process. Specifically, the first row of knots contains knots formed from two long knot segments, one of which can be placed flat on the base plane. Between each of these two so-called large knots are knots referred to as small knots, formed from two relatively short knot segments, in which case both segments are positioned at an angle to the base plane. The second row of knots, which is completely lifted from the base plane, contains various variations of knots of intermediate size. Each of the nodal sections is spaced apart from the base plane and from the second plate, for example, parallel to each other, whereas the second nodal section, which is tilted as a single section or tilted more strongly, is in linear contact with the second plate.

[0017] The first variation of the nodule is formed from a shorter of two nodule sections, one long and one short, which are parallel to the plate, and a longer second nodule section. In the second variation, the opposite situation exists. In this case, a shorter, inclined nodule section that reaches the second plate is connected to the longer nodule section parallel to the plate. The webs connecting the nodules to each other extend from one long nodule section to another, or between the two short nodule sections, and therefore each web has a certain width of its own.

[0018] Furthermore, by varying the feed length during manufacturing, expanded metal grids with three or more distinct rows of knots, for example, three or four distinct rows of knots, can also be realized. It is also conceivable that each of the various types of rows of knots consists only of knots where adjacent sections have different lengths in each individual case.

[0019] In general, a nodal section is also called a half-nodal point. When a nodal section is positioned parallel to the base plane, it is also simply called a horizontal nodal section, regardless of the actual orientation of the plate assembly in space. In various forms of expanded metal, an angle of, for example, at least 90° and up to 150° may be formed between the two nodal sections of a single nodal section.

[0020] The plate commonly referred to as the second plate is, in particular, a bipolar plate. As is well known, a bipolar plate may consist of two half-metal sheets, with a passage for the coolant formed between them. The second plate can also be configured as a monopolar plate. In both the bipolar and monopolar cases, the term separator is also used for the second plate.

[0021] A first plate-like assembly, abbreviated as the first plate, which defines the base plane, includes a proton-permeable polymer electrolyte membrane (PEM). In a typical configuration, the PEM is adjacent to porous anode and cathode catalyst layers, as well as a porous gas diffusion layer, which also belong to the first plate. Therefore, within a plate stack containing multiple plate assemblies of the same type, there are contact points between various gas diffusion layers and the expanded metal grid. Regardless of the geometric configuration of the expanded metal, the expanded metal grid in any case forms a flow region for the operating medium of the electrochemical system.

[0022] In the configuration already described, in which expanded metal manufactured by variable feed is used, the rows of nodules lifted from the base plane may be separated from the base plane by a distance corresponding to, for example, the distance between the two plates, i.e., at least 30% and up to 60% of the thickness of the expanded metal grid.

[0023] According to another possible embodiment, the nodules of the first type of nodule row are in contact with the first plate of the plate assembly, while the nodules of the second type of nodule row are in contact with the second plate. In this case, all nodule sections of the nodules may have a uniform length, and the first and second type of nodule rows are arranged alternately when viewed laterally in the expanded metal. Assuming the plate assembly is positioned horizontally, the nodules of the various nodule rows are located at different heights from one another, which can be considered a corrugation in the laterally in the expanded metal. This corrugation opens up particularly large flow cross-sections within the plate assembly. In this case, all webs have a uniform width defined by the feed during the manufacturing process.

[0024] In an improved embodiment, the variable feed that appears in the nodular section of non-uniform width is combined with the wave formation of the expanded metal. Also in this case, as in the configuration already described in detail, there are various nodular columns, and in one nodular column, long nodules and short nodules are arranged alternately, while in the second nodular column, nodules of various intermediate lengths exist. Different from the configuration already described, this improved embodiment may be particularly excellent in that the nodules of intermediate length are lifted particularly greatly from the first plate. By the horizontal nodular section distance of these nodules from the first plate within a range of, for example, 50% ± 10%, particularly 50% ± 5% of the distance between the plates, a plurality of flow passages extending longitudinally through the plate assembly and dimensioned particularly large are formed, and these flow passages may extend from the inlet to the outlet of the flow region.

[0025] Hereinafter, four examples of the present invention will be described in detail based on the drawings.

Brief Description of the Drawings

[0026] [Figure 1] It is a figure which shows the 1st Embodiment of the expanded metal lattice for an electrochemical cell. [Figure 2] It is a figure which shows the plate assembly of the electrochemical cell containing the expanded metal lattice shown in FIG. 1. [Figure 3] It is another figure which shows the expanded metal lattice shown in FIG. 1. [Figure 4] It is another figure which shows the expanded metal lattice shown in FIG. 1. [Figure 5] It is another figure which shows the expanded metal lattice shown in FIG. 1. [Figure 6] It is a figure which shows the 2nd Embodiment of the expanded metal lattice for an electrochemical cell. [Figure 7] It is a figure which shows the plate assembly of the electrochemical cell containing the expanded metal lattice shown in FIG. 6. [Figure 8]This is another diagram showing the expanded metal grid shown in Figure 6. [Figure 9] This is another diagram showing the expanded metal grid shown in Figure 6. [Figure 10] This is another diagram showing the expanded metal grid shown in Figure 6. [Figure 11] This is another diagram showing the expanded metal grid shown in Figure 6. [Figure 12] This is another diagram showing the expanded metal grid shown in Figure 6. [Figure 13] This figure shows a third embodiment of an expanded metal grid for an electrochemical cell. [Figure 14] This figure shows a plate assembly of an electrochemical cell containing an expanded metal grid, as shown in Figure 13. [Figure 15] This is another diagram showing the expanded metal grid shown in Figure 13. [Figure 16] This is another diagram showing the expanded metal grid shown in Figure 13. [Figure 17] This is another diagram showing the expanded metal grid shown in Figure 13. [Figure 18] This is another diagram showing the expanded metal grid shown in Figure 13. [Figure 19] This is another diagram showing the expanded metal grid shown in Figure 13. [Figure 20] This figure shows a fourth embodiment of an expanded metal grid for an electrochemical cell. [Figure 21] Figure 20 shows a plate assembly of an electrochemical cell containing an expanded metal grid. [Figure 22] This is another diagram showing the expanded metal grid shown in Figure 20. [Figure 23] This is another diagram showing the expanded metal grid shown in Figure 20. [Figure 24] This is another diagram showing the expanded metal grid shown in Figure 20. [Figure 25] This is another diagram showing the expanded metal grid shown in Figure 20. [Figure 26] This is another diagram showing the expanded metal grid shown in Figure 20. [Modes for carrying out the invention]

[0027] The following description applies to all embodiments unless otherwise specified. Contours of parts or parts that correspond to or function in principle equivalently are indicated by the same reference numerals in all drawings.

[0028] The electrochemical cell, denoted by the symbol 1, is a fuel cell in this embodiment, and this fuel cell includes a plurality of stacked plate assemblies 2 of the same type. For the principle structure and function of the stack of electrochemical cell 1, please refer to the prior art cited at the beginning.

[0029] The plate assembly 2 may include an expanded metal grid 3, which is also referred to simply as expanded metal or grid. Furthermore, the plate assembly 2 includes a membrane electrode assembly containing a gas diffusion layer, which is a first plate-shaped assembly 5, also simply referred to as the first plate. Furthermore, the plate assembly 2 may include a second plate 4, which is part of a bipolar plate.

[0030] The surface of plate 5 that contacts the expanded metal 3 defines the base plane of plate assembly 2. There are significant differences between the two plates 4 and 5 in terms of mechanical load resistance. Both plates 4 and 5 are intended to guide electric current, which flows particularly through the contact connection areas between the grid 3 and the various plates 4 and 5. The expanded metal 3 also provides an important function in guiding liquid and / or gaseous media, i.e., the operating medium of the electrochemical cell 1.

[0031] The grid 3 has multiple knots 6, each of which has a first knot section 7 and a knot section 8 inclined relative to the first knot section 7, which can be seen in a partially simplified form in the drawing. In this embodiment, the first knot section 7 is arranged parallel to the plates 4 and 5. The knot sections 7 and 8 are adjacent to each other by a broken line. The angle between the knot sections 7 and 8 is represented by α.

[0032] The nodes 6 of the grid 3 are connected to each other by webs 10 and 11, thereby forming an opening 9 with a basic rhombic shape. The flow passage formed between plates 4 and 5 by the grid 3 is generally indicated by reference numeral 12. The medium flowing through the plate assembly 2 flows collectively in the longitudinal direction of the plate assembly 2, indicated by LR. In the longitudinal direction LR, the mesh dimension SWD (short-range center-to-center distance) of the grid 3 can be measured. The dimension LWD (long-range center-to-center distance) can similarly be measured laterally relative to the longitudinal direction LR using conventional methods. KB indicates the node width, i.e., the matching width of node sections 7 and 8. SH indicates the expanded metal height, i.e., the spacing between plates 4 and 5. The substantially uniform wall thickness to be measured in the horizontal section 7 of the grid 3 is indicated by WS. The nodes 6 are located in node rows KR1 and KR2 extending in the longitudinal direction LR.

[0033] In the embodiments shown in Figures 1 to 5, unlike the embodiments shown in Figures 6 to 14 and Figures 20 to 26, all node rows KR1 and KR2 are formed similarly. Here, all node sections 7 are placed flat on the first plate 5, i.e., on the film electrode assembly. In contrast, in this embodiment, the second plate 4, which is flat in the illustrated region, is connected only by the edges of the second node sections 8, which is acceptable based on the given current capacity and mechanical load capacity of the second plate 4. In the flow direction, i.e., the longitudinal direction LR, each node section 6 of the expanded metal 3 shown in Figure 1 forms an obstacle that fills the space between the plates 4 and 5, and the inclination of the sections 8 contributes to deflecting the medium through the node sections 6 towards the adjacent webs 10 and 11. Each web 10 and 11 connects the horizontal node sections 7 to the inclined node sections 8. This means that the webs 10 and 11 themselves are twisted. Such twisting of the webs 10 and 11 is also given in all other embodiments and contributes to the flowing medium acquiring a motion component perpendicular to the plates 4 and 5. Furthermore, the twisting of the webs 10 and 11, along with the folded shape of the knot 6, enhances the overall stability of the expanded metal 3.

[0034] The embodiments shown in Figures 6 to 12 clearly differ from the embodiments shown in Figures 1 to 5 in that the adjacent sections 7 and 8 of the knot 6 are given different lengths. This is achieved by variable feeding of the metal sheet from which the expanded metal 3 is manufactured.

[0035] In particular, as can be seen from Figure 12, in the expanded metal grid 3 shown in Figure 6, all the nodes 6 of the first node row KR1 are lifted from the film electrode assembly 5. In contrast, as can be seen from Figure 11, the nodes 6 of the second node row KR2 are applied to the thin film electrode assembly 5 in a planar or linear manner. In the latter case, the node row KR2 is formed by alternately arranged long nodes 6 and short nodes 6. The length of the first node section 7 of the long node section 6 is indicated by L1. The inclined node section 8 connected to the long node section 7 has a length L2, which in the illustrated case is equal to length L1. In the node row KR2, the adjacent node section 6 is a short node, and in this case, the two node sections 7 and 8 are inclined in different ways with respect to the plates 4 and 5, respectively. Each of the nodal sections 7 and 8 has a length L3 that is shorter than length L1. By inclining the shorter nodal sections 6 more significantly than the longer nodal sections 6, the shorter nodal sections 6 also extend from the surface of the bipolar plate 4 to the surface of the first plate 5. Therefore, all the nodal sections 6 of the nodal section row KR2 of the grid 3 shown in Figure 6 extend across the entire expanded metal height SH.

[0036] Unlike the nodal portions 6 of the nodal portion row KR2, all nodal portions 6 of the first nodal portion row KR1 are indeed in contact with the second plate 4, but not with the first plate 5. In the case of the first nodal portion row KR1, each nodal portion 6 is given a combination of a short nodal portion section and a long nodal portion section 7,8. If the first nodal portion section 7 is formed as a short nodal portion section having a length L3, then the inclined second nodal portion section 8 is a long nodal portion section having a length L2. In contrast, in the nodal portion row KR1, the adjacent nodal portions 6 are given the opposite length situation, namely the first horizontal nodal portion section 7 is formed as a long nodal portion section having a length L1. The subsequent inclined nodal portion section 8 is a short section having a length L3. The distance d is less than half the expanded metal height SH in the embodiments shown in Figures 6 to 12. Depending on the relationship between the distance d and the expanded metal height SH, and the flexibility of the first plate 5, the first plate 5 may also be fitted against the knots 6 of the first knot row KR1. In other respects, as can be seen from Figure 12, a free space which may belong to the flow passage 12 is formed between the knots 6 of the first knot row KR1 and the plate 5.

[0037] In the embodiments shown in Figures 13 to 19, the nodal portions 6 of the nodal portion row KR1 are lifted from the first plate 5, as can be seen from Figure 18. At the same time, these nodal portions 6 are in contact with the bipolar plate 4, as can also be seen from Figure 18. The reverse is true for the nodal portions 6 of the second nodal portion row KR2. In this case, all the nodal portions 7 are placed on the first plate 5, while the inclined nodal portions 8 are spaced apart from the bipolar plate 4. In cross-section, all the nodal portions 6 of nodal portion rows KR1 and KR2 have a uniform cross-sectional shape, as can be seen from comparing Figures 18 and 19. The length of both nodal portions 7 and 8 is L1. Overall, in the embodiments shown in Figures 13 to 19, there is a corrugated expanded metal 3.

[0038] In the embodiments shown in Figures 24 to 26, the features of the embodiments shown in Figures 13 to 19 are combined with the features of the embodiments shown in Figures 6 to 12. Therefore, in the case of Figures 20 to 26, there is a corrugated expanded metal 3 manufactured using variable feed. Figure 25 shows the cross-sectional shape of the nodules 6 in the second nodule row KR2. The common point with the configuration shown in Figure 11 is that nodules 6 formed from two long nodule sections 7 and 8 and nodules 6 formed from two short nodule sections 7 and 8, each having a length L3, are arranged in a row while maintaining the spacing that exists as an opening 9, alternately in the longitudinal direction LR. However, unlike the configuration shown in Figure 11, in the case of Figure 25, all nodules 6 of the nodule row KR2 are spaced apart from the bipolar plate 4. With respect to the first nodule row KR1, the cross-sectional configuration that can be seen from Figure 26 is basically comparable to the cross-sectional configuration shown in Figure 12. This means that all the inclined nodal sections 8 are in contact with the bipolar plate 4, while the horizontal nodal sections 7 are lifted from the first plate 5. The distance d between the horizontal nodal sections 7 and the first plate 5 corresponds to approximately half the expanded metal height SH in the case of Figure 26. In this case, the longer nodal sections 7, each having a length L1, are somewhat further from the first plate-shaped assembly 5 than the shorter nodal sections 7, each having a length L3. Overall, the embodiments shown in Figures 20 to 26 provide a particularly wide open cross-section of the flow passage 12, while simultaneously providing a planar, material-safe contact of the expanded metal 3 in the first plate-shaped assembly 5. [Explanation of Symbols]

[0039] 1. Electrochemical cell, fuel cell 2 Plate Assembly 3. Expanded metal, grid 4. Second plate, bipolar plate 5. First plate-shaped assembly, MEA 6. Node 7. First nodal section division 8. The tilted second node section 9 aperture 10 Web 11 Web 12 Flow passage α angle d distance KB Nodule width KR1,KR2 Nodule row L1 Length L2 Length L3 Length LR Longitudinal Direction LWD (Left-Wide Width) SH Expanded Metal Height SWD Center distance in short direction WS wall thickness

Claims

1. A plate assembly (2) for an electrochemical cell (1), comprising a grid formed as expanded metal (3) provided to be sandwiched between a first plate (5) located on a base plane and a second plate (4) parallel to the first plate (5), the grid includes a plurality of nodules (6) and webs (10, 11) connecting the nodules (6), wherein rows of nodules (KR1, KR2) defining the longitudinal direction (LR) are formed in a plan view of the grid (3) from above, and all nodules (6) have a planar folded shape with a fold line oriented laterally with respect to the longitudinal direction (LR) that separates two nodules (7, 8) from each other, In at least a subset of the knot portions (6), one knot portion portion (7) of each knot portion portion is arranged at least substantially parallel to the plates (4, 5), A plate assembly (2) characterized in that an angle (α) of at least 90° to a maximum of 150° is formed between the two nodal portions (7, 8) of a single nodal portion (6).

2. The plate assembly (2) according to claim 1, characterized in that, in at least some of the knot portions (6) belonging to the subset, the first knot portion section (7) forms an angle of less than 15 degrees with the base plane and is in particular placed planarly on the base plane.

3. The plate assembly (2) according to claim 2, characterized in that it also belongs to the subset but has additional nodular portions (6) each having one nodular portion section (7) spaced apart from the base plane.

4. The plate assembly (2) according to any one of claims 1 to 3, characterized in that there is a knot (6) having a matching length (L1, L2) for the knot sections (7, 8).

5. The plate assembly (2) according to claim 4, characterized in that the lengths (L1, L3) of the first knot section (7) differ from the lengths (L3, L1) of the second knot section (8) in at least some knot sections (6).

6. The plate assembly (2) according to claim 5, wherein in one row of the rows of knots (KR2), only knots (6) having two knot sections (7, 8) of the same length are arranged, and knots (6) having two long knot sections (7, 8) alternate with knots (6) formed from two short knot sections (7, 8); and in another row of knots (KR1), only knots (6) having knot sections (7, 8) of non-uniform length are arranged, wherein in this case, one knot (6) having at least a long section (7) that is substantially parallel to the plate (4, 5) and a shorter section (8) that is more strongly inclined, and knots (6) having at least a short section (7) that is substantially parallel to the plate (4, 5) and a relatively strongly inclined long section (8) are arranged alternately in a row.

7. The plate assembly (2) according to claim 6, characterized in that, of a row of nodules (KR2) formed from nodules (6) having nodules (7, 8) of the same length, at least a nodules (7) that is substantially parallel to the plates (4, 5) is in contact with the base plane, whereas of another row of nodules (KR1), at least a nodules (7) that is substantially parallel to the base plane is raised from the base plane by a distance (d) that corresponds to the gap (SH) between both plates (4, 5), i.e., at least 30% to a maximum of 60% of the thickness of the grid (3).

8. Use of the plate assembly (2) according to claim 1 in a fuel cell (1).

9. A stack of electrochemical cells (1), comprising a plurality of plate assemblies (2) according to claim 1, wherein the plate assemblies (2) have a grid formed as expanded metal (3) and two plates (4, 5) in contact with the grid (3), namely a membrane electrode assembly (5) as a first plate and a bipolar plate (4) as a second plate.

Images