Separators for electrochemical systems

Abstract

The present invention relates to a separator (300a, 400a, 500a, 600a, 700a, 800a) for an electrochemical system (1), the separator comprising: at least one first through-opening (11a) for guiding a reaction medium through the separator (300a, 400a, 500a, 600a, 700a, 800a); an active area (18) having a structure for guiding the reaction medium along a flat side of the separator (300a, 400a, 500a, 600a, 700a, 800a); and a first sealing structure (12a) surrounding the first through-opening (11a) for sealing the first through-opening (11a). The first sealing structure (12a) has a first feedthrough (13a) for guiding the reaction medium through the first sealing structure (12a), the feedthrough pointing away from the active area. The invention also relates to a bipolar plate (300, 400, 500, 600, 700, 800) for an electrochemical system (1), the bipolar plate comprising the separator (300a, 400a, 500a, 600a, 700a, 800a) described.

Description

Technical Field

[0001] The present invention generally relates to a separator for an electrochemical system, to a bipolar plate including such a separator, and to an electrochemical system including a plurality of separators or bipolar plates. Background Art

[0002] Known electrochemical systems usually include a plurality of separators or a plurality of bipolar plates (each combined by two separators), which are arranged in a stack so that each two adjacent separators or bipolar plates enclose an electrochemical cell or a humidifier cell. The separator and the bipolar plate combined by two separators can be used, for example, to electrically contact the electrodes of a single electrochemical cell (e.g., a fuel cell cell), and / or to electrically connect adjacent cells (series connection of cells). The separator / bipolar plate can also be used to dissipate the heat generated by the cells between the separators / bipolar plates. This waste heat can be generated, for example, during the conversion of electrical energy or chemical energy in a fuel cell cell.

[0003] The separators and therefore the bipolar plates formed therefrom usually each comprise at least one through-opening. The through-openings of the stacked separators / bipolar plates are aligned with one another or at least partially overlap one another, or in a stack of bipolar plates of an electrochemical system, a channel for feeding or discharging a medium is subsequently formed. In order to seal the through-openings or medium channels formed by the through-openings of the separators / bipolar plates, known separators / bipolar plates also include sealing systems, which are each arranged in the through-openings of the separators / bipolar plates. The sealing system can, for example, be formed as a sealing bead that is molded into and in particular convexly pressed into the particle plate.

[0004] The separator may additionally comprise a channel structure for supplying one or more media to the active area of ​​the separator / bipolar plate and / or a channel structure for transporting the media away. The active areas of two separators / bipolar plates arranged relative to each other on opposite sides of the cell may, for example, enclose or delimit an electrochemical cell or a humidifier cell. For example, the medium may consist of a fuel, such as hydrogen or methanol, a reaction gas, such as air or oxygen, or may be present as a coolant in the form of a feed medium, and may consist of reaction products and may be a heated coolant in the form of an exhaust medium. In the case of a fuel cell cell, the reaction medium, i.e. the fuel and the reaction gas, is usually guided on the surfaces of the bipolar plates facing away from each other, while the coolant is guided into a cavity formed between the two separators (forming the bipolar plates).

[0005] The sealing system arranged around the through-opening of the separator / bipolar plate can respectively have one or more passages. These passages are used to establish a fluid connection between the through-opening of the separator / bipolar plate and the active area, or between the through-opening of the bipolar plate and the cavity of the bipolar plate. Corresponding passages are known, for example, from DE 102 48 531 A1, for example in the form of small holes on the side of the sealing collar.

[0006] In addition, known separators or bipolar plates generally also include distribution areas arranged between the through-openings of the plates and the active areas, which are used to distribute the medium, which is fed to a specific plate via the through-openings of the plates so that it is distributed as evenly as possible on the active area of ​​the plates. For this purpose, the distribution area may include distribution structures in the form of webs and channels, for example. However, other distribution structures are also conceivable. Comparable structures are used to collect the medium removed from the active area and guide it to the through-openings; since only the flow direction is different, the area in question is also referred to as the distribution area here. In order to ensure good efficiency of the electrochemical system, it is generally advantageous to design the surface area of ​​the active area of ​​the separator or bipolar plate to be as large as possible, and to maintain the proportion of the surface area of ​​the distribution area and to make the through-openings as small as possible. However, at the same time, it is necessary to ensure that the distribution of the medium fed to the plate via the through-openings on or through the active area is as uniform as possible. Summary of the invention

[0007] It is therefore an object of the present invention to create a separator or bipolar plate for an electrochemical system which ensures that the electrochemical system operates as efficiently as possible.

[0008] Therefore, a separator for an electrochemical system is proposed, comprising:

[0009] at least one first through opening for directing a reaction medium through the partition;

[0010] an active region including structure for directing a reactive medium along the planar sides of the separators; and

[0011] a first sealing structure, the first sealing structure surrounding the first through opening and used for sealing the first through opening;

[0012] Wherein, the first sealing structure comprises a first passage for guiding the reaction medium through the first sealing structure;

[0013] wherein the first passage comprises a first passage opening facing away from the first through opening;

[0014] wherein the first passage defines a first direction leading from the first through-opening towards the first passage opening; and wherein the first through-opening is fluidly connected to the active area by means of the first passage.

[0015] Compared with known separators, the separator provided by the present application is characterized in that the first passage is arranged and formed such that the first direction forms an angle (angular dimension) of at least 100 degrees with the second direction.

[0016] The second direction is defined by the shortest straight connecting line connecting the first passage opening of the first passage to the medium inlet or outlet of the active area, wherein the second direction points from the first passage opening of the first passage to the medium inlet or outlet of the active area. The shortest straight connecting line defining the second direction can be determined purely geometrically and has nothing to do with the flow direction of the medium along the plate surface. The first direction and the second direction each define a guiding arrow. The angle (included angle) of at least 100 degrees formed by the first direction and the second direction will be the angle formed by the corresponding arrow ends, which angle is less than or equal to 180 degrees (no reflection angle).

[0017] The orientation of the first passage provided here has such an effect that when the medium flows from the first through opening to the active area, the medium is at least partially redirected on its path from the first passage opening to the entrance of the active area. Typically, the flow rate of the medium is typically at least partially reduced. In this way, a particularly uniform distribution of the medium on the active area can be achieved. For example, the distribution area (which is typically arranged between the first through opening and the active area and formed to guide and distribute the medium on the path from the first passage opening to the entrance of the active area) is formed to be smaller in the case where the partition is provided in the present application, and the active area is correspondingly formed to be larger. Therefore, the power density of the electrochemical system including the partition provided in the present application can be improved. Similarly, it is possible to supply the coolant at least at a lower pressure level than the conventional partition, thereby resulting in a reduction in energy consumption of the entire system. The angle formed by the first direction and the second direction can also be at least 105 degrees, preferably at least 110 degrees, and particularly preferably at least 120 degrees. In some designs, the angle may even be at least 140 degrees.

[0018] The first passage typically also has a second passage opening facing the first passage opening.The first direction defining the orientation of the first passage may be defined by the shortest straight line, eg also called a straight through line, connecting the first passage opening to the second passage opening.

[0019] The partition plate may also include a peripheral sealing structure, which surrounds the first sealing structure and the active area. The peripheral sealing structure and the first sealing structure may then be formed in such a way that a portion of the first sealing structure and a portion of the peripheral sealing structure define a channel defined by the first sealing structure and the peripheral sealing structure. In this case, the first passage opening that deviates from the first through opening may, for example, be connected to the above-mentioned inlet or outlet fluid of the active area by means of the channel of the first sealing structure and the peripheral sealing structure. Therefore, the medium flow between the first passage and the active area is guided, redirected and / or transferred by the peripheral sealing structure at least in some areas. This has generally led to enhanced distribution along the width, that is, even before reaching the distribution area, the medium is also perpendicular to the active area in the direction of the entire medium flow direction, and the width is greater than the sum of the width of the through opening through which the medium flows and the width length of the passage to the first passage opening in the same direction. The wall of the sealing structure that exists anyway forms a medium conducting structure in the process, and makes it possible to make optimal use of the available space. No additional components, such as a sealing frame or the like, are required to guide the medium.

[0020] The partition plate may also include at least a second through opening for guiding a coolant or a reaction medium through the partition plate. Subsequently, the partition plate generally further includes a second sealing structure surrounding the second through opening for sealing the second through opening.

[0021] The peripheral sealing structure and the second sealing structure can then be formed in such a way that a portion of the second sealing structure and a portion of the peripheral sealing structure define a channel defined by the second sealing structure and the peripheral sealing structure. The first passage opening facing away from the first through-opening can then be connected to the above-mentioned inlet or outlet fluid of the active area by means of the channel defined by the second sealing structure and the peripheral sealing structure. Thus, the medium flow between the first passage and the active area is guided, redirected and / or diverted at least in some areas by the peripheral sealing structure and the second sealing structure, without requiring a separate component or structure for this purpose.

[0022] The first sealing structure and the second sealing structure can then be formed in such a way that a portion of the first sealing structure and a portion of the peripheral sealing structure define a channel bounded by the first sealing structure and the second sealing structure. The first passage opening facing away from the first through-opening can then be fluidically connected to the above-mentioned inlet or outlet of the active area by means of the channel defined by the second sealing structure and the first sealing structure. Thus, the medium flow between the first passage and the active area is guided, redirected and / or diverted by the first sealing structure and the second sealing structure at least in some areas.

[0023] The separator can be formed of metal, preferably stainless steel. The thickness of the metal plate formed with the separator can be, for example, no more than 150 μm, no more than 120 μm or no more than 100 μm. The separator preferably includes at least partially a coating on its surface, which is used to distribute the reaction medium.

[0024] The first sealing structure and / or the second sealing structure are formed as a plurality of sealing ridges pressed into the partition, or as a sealing ridge pressed into the partition. In particular, it may be advantageous when the peripheral sealing structure encloses all the first sealing structures and the second sealing structure, that is, it is advantageous when the peripheral ridge extends so as to surround all other sealing structures of the partition. Alternatively or additionally, the structure for guiding the active area of ​​the reaction medium can also be pressed into the partition.

[0025] The partition may include a distribution area arranged between the first through opening and the active area. In particular, the first passage opening of the first passage may be fluidically connected to the active area by means of the distribution area. The distribution area may include a distribution structure configured to distribute the reaction medium on the active area, the reaction medium traveling from the first passage opening of the first passage and being introduced into the distribution area, and / or configured to collect or gather the reaction medium traveling from the active area and flowing to the first passage opening of the first passage towards the first passage opening. The distribution structure of the distribution area may also be convexly pressed into the partition.

[0026] The partition may be formed from only one layer of metal sheet, for example only one layer of stainless steel sheet.

[0027] The first passage opening of the first passage of the partition can be formed as a through-window or through-hole or through-cut in the partition. In this case, the medium can flow from the first flat side of the partition through the first passage opening to the second flat side of the partition and vice versa. When the first passage opening of the first passage of the partition is formed as a through-window, through-hole or through-cut on the partition, it is therefore particularly arranged at a distance from the border or from the side edge of the partition.

[0028] Furthermore, a bipolar plate for an electrochemical system is proposed. The bipolar plate comprises a first separator of the above-described type and a second separator, wherein the first separator and the second separator are formed of metal, preferably stainless steel. The first separator and the second separator of the bipolar plate are connected to each other. The second separator also comprises a first through-opening, which is aligned with the first through-opening of the first separator, wherein the mutually aligned first through-openings of the first separator and the second separator form the first through-opening of the bipolar plate. The active area of ​​the first separator then forms the active area of ​​the bipolar plate.

[0029] The first separator and the second separator of the bipolar plate may be welded together, in particular connected by laser welding.

[0030] Preferably, only one first separator and only one second separator form the bipolar plate. For example, the first separator of the bipolar plate and the second separator of the bipolar plate can each consist of only one layer of metal plate, for example they can each be formed by only one layer of stainless steel plate, wherein the metal plate can optionally, in particular locally, include a coating. In contrast to many methods of the prior art, in this way one or two separate sealing frames can be omitted. In this case, the bipolar plate is therefore made of only two layers, and in particular of two metal layers.

[0031] If the first separator of the bipolar plate includes the above-mentioned channel defined by the first sealing structure of the first separator and the peripheral sealing structure of the first separator, the connection between the first separator and the second separator of the bipolar plate, in particular the welded connection, can be at least partially formed in the area of ​​the channel defined by the first sealing structure and the peripheral sealing structure of the first separator.

[0032] If the first separator of the bipolar plate includes the above-mentioned channel defined by the second sealing structure of the first separator and the peripheral sealing structure of the first separator, the connection between the first separator and the second separator of the bipolar plate, in particular the welded connection, can be formed alternatively or additionally in the area of ​​the channel defined by the second sealing structure of the first separator and the peripheral sealing structure of the first separator.

[0033] Furthermore, if the first separator of the bipolar plate includes the above-mentioned channel defined by the first sealing structure of the first separator and the second sealing structure of the first separator, the connection between the first separator and the second separator of the bipolar plate, in particular the welded connection, can be formed alternatively or additionally in the area of ​​the channel defined by the first sealing structure of the first separator and the second sealing structure of the first separator.

[0034] This dual use also reduces the space required for feeding and distributing the medium and increases the surface area available as an effective surface.

[0035] If the first separator of the bipolar plate includes the above-mentioned second through-opening, the second separator of the bipolar plate may also include a second through-opening. The second through-opening of the first separator and the second through-opening of the second separator can then be aligned with each other and form the second through-opening of the bipolar plate. The first separator and the second separator of the bipolar plate can also enclose a cavity for guiding a coolant through the bipolar plate. The cavity is usually defined by the rear side of the active area of ​​the bipolar plate facing the cavity. In this way, heat can be dissipated from the active area of ​​the bipolar plate by means of the coolant guided through the cavity.

[0036] The cavity of the bipolar plate can be fluidically connected, for example, to the second through-opening of the bipolar plate. The fluid connection between the second through-opening of the bipolar plate and the cavity of the bipolar plate can, for example, lead to the second through-opening of the bipolar plate on the side of the second through-opening of the bipolar plate facing the active area. In this way, the coolant can be introduced from the second through-opening of the bipolar plate into the cavity, or from the cavity into the second through-opening of the bipolar plate in the most direct way. This can contribute to particularly effective cooling of the bipolar plate.

[0037] The second through-opening of the bipolar plate can be formed or shaped in such a way that the cross-section of the second through-opening of the bipolar plate, which is determined to be parallel to the flat surface plane of the bipolar plate, increases toward the active area at least in the end section of the second through-opening of the bipolar plate facing the active area. For example, in the active area, the second through-opening parallel to the entire medium flow direction can have a maximum diameter or maximum width, which has a first end facing the active area. The above cross-section of the second through-opening can then be determined to be perpendicular to the maximum diameter of the second through-opening. In the continuous section along the maximum diameter of the second through-opening, the above cross-section of the second through-opening can always increase strictly monotonically toward the active area. The adjacent section can have a first end facing the active area and a second end away from the active area. The distance between the first end of the continuous section and the first end of the maximum diameter of the second through-opening can be 10% of the length of the maximum diameter of the second through-opening. Alternatively or additionally, the distance between the second end of the continuous section and the first end of the maximum diameter of the second through-opening can be 40% of the length of the maximum diameter of the second through-opening. The boundary transition of the through-opening (which extends substantially perpendicularly to the overall medium flow direction of the active area) can still be rounded (in particular to improve stampability), which contributes to particularly effective cooling of the active area of ​​the bipolar plate, in particular when the second through-opening of the bipolar plate is in fluid communication with the above-mentioned cavity of the bipolar plate, for example for introducing a coolant into the cavity or for discharging a coolant from the cavity. For example, the fluid connection between the second through-opening and the cavity can in this way have a particularly large flow cross section, in particular at the location where the connection opens into the second through-opening.

[0038] As an alternative or in addition, the first through-opening of the bipolar plate can be formed or shaped in such a way that the cross-section of the first through-opening of the bipolar plate, which is determined to be parallel to the plane surface plane of the bipolar plate, increases in the direction away from the active area at least in the end section of the first through-opening facing away from the active area. For example, in the active area, the first through-opening parallel to the entire medium flow direction can have a maximum diameter, which has a first end facing the active area. The above-mentioned cross-section of the first through-opening can then be determined to be perpendicular to the maximum diameter of the first through-opening. In the continuous section along the maximum diameter of the first through-opening, the above-mentioned cross-section of the first through-opening can always increase strictly monotonically in the direction away from the active area. The adjacent section can have a first end facing the active area and a second end away from the active area. The distance between the first end of the continuous section and the first end of the maximum diameter of the first through-opening can be 60% of the length of the maximum diameter of the first through-opening. And, alternatively or additionally, the distance between the second end of the continuous section and the first end of the maximum diameter of the first through-opening can be 90% of the length of the maximum diameter of a through-opening.

[0039] Furthermore, the first through-opening of the bipolar plate and the second through-opening of the bipolar plate may be arranged along a direction transverse to or perpendicular to the shortest straight connecting line between the first through-opening and the active area.

[0040] Alternatively, it is conceivable that the second through-opening of the bipolar plate is arranged between the first through-opening of the bipolar plate and the active area of ​​the bipolar plate.

[0041] In addition, an electrochemical system is provided, comprising a plurality of separators or bipolar plates as described above, and comprising a membrane assembly arranged between the bipolar plates, in particular comprising membrane assemblies respectively arranged between adjacent bipolar plates. For example, the electrochemical system can be formed as a fuel cell monomer stack or an electrolyzer. The membrane assemblies can, for example, each include at least one electrolyte membrane. Alternatively, the electrochemical system can also be formed as a humidifier, wherein the membrane assemblies can, for example, each include at least one water exchange membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Exemplary embodiments of separators, bipolar plates, and electrochemical systems are depicted in the accompanying drawings and are described in more detail in the description that follows. In the drawings:

[0043] Figure 1 schematically illustrates a perspective view of an electrochemical system including a plurality of bipolar plates;

[0044] FIG. 2A schematically shows a known separator in a top view;

[0045] FIG2B schematically shows a cross section of a stack of known bipolar plates;

[0046] Figure 3A A partition of the type provided by the present application according to a first embodiment is schematically shown in a top view;

[0047] Figure 3B The top view schematically shows Figure 3A Details of the clapboards;

[0048] Figure 3C Schematically shows a cross section of an electrochemical system comprising a stack of bipolar plates, each of which comprises Figure 3A and 3B the bulkhead shown; and

[0049] Figures 4 to 8 Further embodiments of separators of the type provided in the present application are each schematically shown in a top view. DETAILED DESCRIPTION

[0050] Figure 1 An electrochemical system 1 of the type provided in the present application is shown, which includes a plurality of identical metal separators 2 arranged in a stack and stacked along the z-direction 7. The stacked bipolar plates 2 are sandwiched between two end plates 3 and 4. The z-direction 7 is also referred to as the stacking direction. The bipolar plates 2 each include two individual plates connected to each other (see, for example, 2B). In this example, the system 1 is a fuel cell stack. Therefore, two adjacent bipolar plates 2 of the stack enclose an electrochemical cell unit between each other, which is used, for example, to convert chemical energy into electrical energy. These electrochemical cell units typically each include a membrane electrode assembly (MEA) (see, for example, FIG. 2B). These MEAs typically each include at least one membrane, such as an electrolyte membrane. In addition, a gas diffusion layer (GDL) can be arranged on one or both surfaces of the MEA.

[0051] In alternative embodiments, the system 1 can also be formed as an electrolyzer, a compressor or a redox flow battery. Bipolar plates can also be used in these electrochemical systems. The composition of these bipolar plates can then correspond to the composition of the bipolar plates 2 explained in more detail here, the medium being guided onto or through the separators in the case of an electrolyzer, in the case of an electrochemical compressor or in the case of a redox flow battery being different from the medium used for the fuel cell system. The same applies to separators, in particular separators of humidifiers.

[0052] The z-axis 7 and the x-axis 8 and the y-axis 9 form a right-handed Cartesian coordinate system. The end plate 4 comprises a plurality of medium connections 5, via which a medium can be fed to the system 1 and via which a medium can be discharged from the system 1. These media that can be fed to the system 1 and can be discharged from the system 1 can, for example, comprise a fuel of molecular hydrogen or methanol, a reaction gas such as air or oxygen, a reaction product such as water vapor, or a depleted fuel, or a coolant such as water and / or ethylene glycol.

[0053] FIG. 2A shows a portion of a bipolar plate 2 known from the prior art in a top view, wherein the bipolar plate 2 according to FIG. 2A can be used in an electrochemical system of the type from system 1, for example. Here and in the following, repeated features are indicated by the same reference numerals. The bipolar plate 2 is formed by two integrally bonded individual plates or separators 2a, 2b, of which only the first separator 2a is visible in FIG. 2A, which covers the second separator 2b. The separators 2a, 2b can be made of metal plates, for example of only one stainless steel plate. The separators 2a, 2b include mutually aligned through openings, which form through openings 11a, 11b, 11c of the bipolar plate 2. When a plurality of bipolar plates of the type of bipolar plate 2 are stacked, the through openings 11a to 11c form a duct extending through the stack 2 along the stacking direction 7 (see Figure 1 ). Typically, each conduit formed by the through openings 11a-c is fluidically connected to one of the ports 5 in the end plate 4 of the system 1. For example, the conduits formed by the through openings 11a, 11b are used to supply fuel and reactant gases to the electrochemical cells of the fuel cell stack 2. Conversely, coolant can be introduced into the stack 2 or removed from the stack 2 via the conduits formed by the through openings 11c.

[0054] In order to seal the through-openings 11a-c relative to the interior of the stack 2 and relative to the surrounding area, the first separator 2a comprises flanges 12a, 12b, 12c, which are each arranged around the through-openings 11a-c and each completely enclose the through-openings 11a-c. On the rear side of the bipolar plate 2 facing away from the observer of FIG. 2A, the second separator 2b comprises a suitable flange for sealing the through-openings 11a-c (not shown).

[0055] In the electrochemically active area 18 of the bipolar plate 2, the first separator 2a includes a flow field 17 on its front side facing the observer of Figure 2A, which includes structures for guiding the reaction medium along the front side of the separator 2a. In Figure 2A, these structures are provided by a plurality of webs and channels extending between the webs and defined by the webs. Figure 2A only shows a cross section of the active area 18 on the front side of the bipolar plate 2. On the front side of the bipolar plate 2A facing the observer of Figure 2A, the first separator 2a also includes a distribution or collection area 20. The distribution or collection area 20 includes a distribution structure, which is configured to distribute the medium from the through opening 11a, which is introduced into the distribution or collection area 20 across the active area 18, and / or is configured to collect or gather the medium from the activation area 18, which flows toward the through opening 11a. The distribution structure of the distribution or collection area 20 in Figure 2A is also provided by webs and channels extending between the webs and defined by the webs.

[0056] The first partition 2a also comprises a peripheral lip 12d which surrounds the flow field 17, the distribution or collecting area 20, and the through-openings 11a, 11b and seals them (the flow field 17, the distribution or collecting area 20, and the through-openings 11a, 11b) relative to the through-opening 11c, i.e. relative to the coolant circuit and relative to the surrounding area of ​​the system 1. The peripheral lip is thus a sealing element, similar to the edge referred to herein as a sealing edge. The structure of the active area 18, the distribution structure of the distribution or collecting area 20, and the lip 12a-d are formed as one piece with the partition 2a and are formed integrally in the partition 2a, for example, by a embossing or deep drawing process.

[0057] By means of the passages 13a through the flange 12a, the distribution channels of the distribution or collection area 20 of the first separator 2a are connected to the through-opening 11a or to the pipeline fluid formed by the through-opening 11a through the stack 2. For the sake of clarity, only some of the passages 13a through the flange 12a are indicated by reference numerals in FIG. 2A. Likewise, the distribution structure of the distribution or collection area 20 is connected to the structure or channel fluid of the flow field 17. In this way, by means of the passages 13a in the flange 12a and by means of the distribution structure of the distribution or collection area 20, the medium guided through the through-opening 11a can be introduced into the flow field 17 of the active area 18 of the bipolar plate 2.

[0058] In a corresponding manner, the through-opening 11 b or the duct formed by the through-opening 11 b through the stack 2 is in fluid communication with the distribution and collection region and, by means of the distribution and collection region, is fluidly connected to the flow field on the rear side of the bipolar plate 2 facing away from the observer of FIG. 2A . Conversely, the through-opening 11 c or the duct formed by the through-opening 11 c through the stack 2 is in fluid communication with the cavity 22 which is enclosed or surrounded by the separators 2 a, 2 b and is formed so as to conduct a cooling liquid through the bipolar plate 2.

[0059] The passages 13a passing through the flange 12a each include a first passage opening 13a' at its end facing away from the through-opening 11a, and each include a second passage opening 13a". The shortest straight connecting line between the second passage opening 13a" and the first passage opening 13a' is defined for each passage 13a passing through the flange 12a in a first direction 14a (short dashed arrow), which indicates the orientation of the corresponding passage 13a. Furthermore, the shortest straight connecting line between the first passage opening 13a' and the inlet or outlet 16 of the active area 18 defines a second direction 15a (dash-dotted arrow) for each passage 13a passing through the flange 12a. The first directions 14a assigned to the passages 13a are each guided from the through-opening 11a toward the first passage opening 13a'. Furthermore, the second directions 15a assigned to the passages 13a are each guided from the first passage opening 13a' toward the active area 18.

[0060] FIG. 2A shows, by way of an exemplary example, one of the passages 13a passing through the flange 12a, a first direction 14a and a second direction 15a assigned to the passage 13a, respectively indicated by arrows. The direction of the arrow does not necessarily reflect the flow direction of the medium. Depending on the use of the bipolar plate 2 or separator 2a according to FIG. 2A, the medium may flow in the direction of the arrow, i.e. from the through opening 11a toward the active area 18, or in the opposite direction of the arrow, i.e. from the active area 18 toward the through opening 11a. Obviously, corresponding to the above definition, the remaining passages 13a passing through the flange 12a shown in FIG. 2A give the first direction 14a and the second direction 15a in the same way.

[0061] In the bipolar plate 2 or separator 2a known in the prior art shown in FIG. 2A , the first direction 14a and the second direction 15a highlighted by the arrows include an angle of approximately 20°, which is represented by a dashed arc. For the passage through the flange 12a arranged farthest to the left in FIG. 2A , the angle assigned to the passage between the first direction and the second direction is approximately 90 degrees. In other words, the passage 13a through the flange 12a surrounding and sealing the through-opening 11a is arranged on one side of the through-opening 11a or the flange 12a facing the active area 18. When the medium from the through-opening 11a flows through the passage 13a, the medium therefore, at this time, flows to the active area 18 or flows approximately to the active area 18.

[0062] FIG. 2B shows a cross section taken through a stack comprising a bipolar plate 2 of the type shown in FIG. 2A , wherein the cross-sectional plane is given by the straight line AA shown in FIG. 2A . Each of the bipolar plates 2 is formed by two metal separators 2a, 2b bonded together. For example, the separators 2a, 2b of the bipolar plate 2 can each be bonded by welding, and in particular by laser welding connection. The electrochemical cell comprises a membrane 19, for example in the form of an electrolyte membrane, which is arranged between adjacent bipolar plates 2 of the stack. In addition, in each case, a flange 12a for sealing the through-opening 11a, a distribution or collection area 20 comprising a distribution structure in the form of a mesh and a channel, and a passage 13a through the flange 12a are highlighted, by means of which the through-opening 11a is fluidly connected to the distribution or collection area 20 and the active area 18, respectively. In the active area, gas diffusion layers 20a, 20b (which enhance the incident flow of the membrane 19 in the active area 18) are additionally arranged on both sides of the membrane 19. Furthermore, a first passage opening 13 a ′ facing the active area 18 and a second passage opening 13 a ″ of the passage 13 a facing the through-opening 11 a are shown.

[0063] Figure 3A A bipolar plate 300 of the type provided in the present application according to a first embodiment is shown in a top view. Figure 3B Shown according to Figure 3A A portion of the bipolar plate 300. And Figure 3C Shown through Figure 3A and 3B A cross section of a stack of bipolar plates 300 of the type shown in FIG. 1 , wherein the respective membrane 19 or its boundary region is arranged between adjacent bipolar plates of the stack. Figure 3C The cutting plane of the cross-sectional view is oriented perpendicular to the flat surface plane of the stacked bipolar plates 300 and thus perpendicular to Figure 3A and 3B The drawing plane. Figure 3C The cutting plane is along Figure 3BThe intersection line BB highlighted in is extended. For example, according to Figure 3C The stack of bipolar plates 300 may be, for example, from Figure 1 System 1 is a stack of electrochemical systems of type.

[0064] Similar to the bipolar plate 2 according to FIG. 2A , according to FIG. 3A to FIG. 3C The bipolar plate 300 is actually formed by combining two metal separators 300a and 300b, wherein the separator 300b is facing Figure 3A , 3B The separators 300a, 300b of the bipolar plate 300 may be formed of stainless steel plates having a thickness of less than 100 μm, for example. The bipolar plate 300 has a rectangular shape, wherein the length of the bipolar plate 300 is approximately three times the width of the bipolar plate 300.

[0065] The bipolar plate 300 includes through openings 11a-c for guiding a medium through the bipolar plate 300. The through openings 11a-c, which are denoted by the same reference numeral, are fluidically connected to each other at opposite sides or ends of the bipolar plate 300. Sealing ridges 12a, 12b, 12c formed to seal the through openings 11a-c surround each through opening 11a-c. In addition, the separator 300a of the bipolar plate 300 includes a peripheral ridge 12d. In contrast to the peripheral ridge 12d of the bipolar plate 2 according to FIG. 2A, the separator 300a of the bipolar plate 300 includes a peripheral ridge 12d. FIG. 3A to FIG. 3C The peripheral rim 12 d of the bipolar plate 300 not only surrounds the active area 18 , the distribution or collecting area 20 , and the through-openings 11 a and 11 b , but also additionally surrounds the through-opening 11 c , thus enclosing all through-openings 11 a - 11 c .

[0066] In accordance with FIG. 3A to FIG. 3C In the separator 300a of the bipolar plate 300 of the embodiment of the present invention, the first through-openings indicated by reference numeral 11a are fluidly connected to each other by means of a passage 13a passing through the sealing ridge 12a, by means of the distribution and collection area 20, and by means of the active area 18. The active area 18 of the separator 300a of the bipolar plate 300 has a rectangular or substantially rectangular shape, wherein the boundaries of the active area 18 extend parallel to the lateral edges of the bipolar plate 300. The active area 18 includes a structure for guiding the reaction medium along the outer surface of the bipolar plate 300, wherein the structure of the active area 18 on the bipolar plate 300 includes channels and webs, thereby resulting in an overall medium flow direction 50. However, it is also conceivable that in a modified embodiment, the structure of the active area 18 can be provided in a form other than by webs and channels.

[0067] In contrast to the bipolar plate 2 according to FIG. 2A , Figure 3A , 3BThe distribution or collection areas 20 of the separator 300a of the bipolar plate 300 each also have a rectangular or substantially rectangular shape, wherein the boundaries of the distribution or collection areas 20 extend parallel to the lateral edges of the bipolar plate 300. The distribution and collection areas 20 include a distribution structure, which is formed so that the medium flowing from the through opening 11a to the active area 18 is distributed as evenly as possible on the active area 18, or so that the medium flowing from the active area 18 to the through opening 11a is collected. The distribution structure of the distribution area or collection area 20 includes a nub-like elevation on the separator 300a of the bipolar plate 300. In a plane parallel to the planar surface of the bipolar plate 300 or parallel to the planar surface of the separators 300a, 300b, the nub-like elevation has, for example, a circular or substantially circular cross-section. However, it is conceivable that, in modified embodiments, the distribution structures of the distribution or collection area 20 can be provided in a form other than nub-shaped protrusions; for example, they can also include webs and channels.

[0068] In the case of the separator 300a of the bipolar plate 300, the second through-openings indicated by the reference numeral 11c are fluidically connected to each other by means of a passage 13c passing through the sealing bead 12c and by means of a cavity 22 enclosed by the separators 300a, 300b of the bipolar plate 300. The cavity 22 serves to conduct a coolant through the bipolar plate 300 and is delimited by the rear side of the active area 18 of the separator 300a facing the cavity 22. The coolant conducted through the cavity 22 can therefore be used in particular to cool the active area 18. Each passage 13c passing through the sealing bead 12c, each forming a fluid connection between the through-opening 11c and the cavity 22 enclosed between the separators 300a, 300b, opens into the through-opening 11c on the side of the through-opening 11c facing the active area 18. This ensures a fluid connection that is as direct as possible between the through-opening 11 c and the cavity 22 , which is defined at least partially or even predominantly by the rear side of the active area 18 facing the cavity 22 .

[0069] The through-opening of the separator 300a of the bipolar plate 300, which is designated by reference numeral 11b, is provided by means of passages 13b through the sealing bead 12b, by means of the distribution and collection area and by means of Figure 3A The active areas of the shielded partitions 300b are fluidically connected to each other.

[0070] The structure of the active area 18, the distribution structure of the distribution or collecting area 20, and the flanges 12a-d are formed in one piece with the separator 300a of the bipolar plate 300. For example, they can each be molded into the separator 300a, in particular by embossing or by deep drawing. The same applies to Figure 3A , 3BThe active area, distribution structure and sealing ridge of the separator 300b of the bipolar plate 300 are hidden in the figure.

[0071] In the separator 300a of the bipolar plate 300, the distribution or collection area 20 is respectively arranged between the through-openings 11a-c and the active area 18. In particular, a corresponding distribution or collection area 20 is arranged between the through-opening 11a and the active area 18, so that the medium flowing from the through-opening 11a to the active area 18 or the medium flowing from the active area 18 to the through-opening 11a flows through one of the distribution or collection areas 20, respectively.

[0072] The through openings 11a-c of the bipolar plate 300 or the separators 300a, 300b of the bipolar plate 300 each have a substantially rectangular shape and are Figure 3A , 3B The through-openings 11a-c are in particular of a square or substantially square shape, wherein the side edges of the through-openings 11a-c are oriented parallel to the side edges of the bipolar plate 300. In the y-direction 9 and thus transversely to the longitudinal direction of the bipolar plate 300, the through-openings 11a-c are arranged close to one another and, in the x-direction 8, the through-openings 11a-c are oriented symmetrically or substantially symmetrically with respect to one another.

[0073] according to FIG. 3A to FIG. 3C The separator 300a of the bipolar plate 300 of FIG. 2A differs from the separator 2A of the bipolar plate 2 according to FIG. 2A in particular in the arrangement and orientation of the passages 13a, which establish a fluid connection between the through-opening 11a and the active area 18. FIG. 3A to FIG. 3C On the partition 300 a of FIG. 2A , in contrast to the partition 2 a according to FIG. 2A , the passage 13 a is arranged on the side of the through-opening 11 a or the sealing bead 12 a facing away from the active region 18 .

[0074] As described in conjunction with FIG. 2A , the orientation of the passage 13a can be described by a first direction 14a. For each passage 13a, the first direction 14a is given by the shortest straight connecting line between the passage openings 13a′, 13a″ and points from the through-opening 11a to the first passage opening 13a′, respectively, wherein the first passage opening 13a′ forms an end of the passage 13a facing away from the through-opening 11a. Figure 3B By way of example, a first direction 14a for one of the passages 13a is shown as a dashed arrow pointing in the negative x-direction 8 and thus away from the active area 18. As described in conjunction with FIG2A , the medium can flow through the passage 13a in the direction of the arrow as well as in the direction opposite to the arrow direction.

[0075] exist Figure 3BThe second direction 15a for the same through-opening 13a is shown in . The second direction 15a is given by the shortest straight connecting line between the first through-opening 13a' and the inlet or outlet 16 of the active area 18 and points from the first through-opening 13a' to the active area 18. Figure 3B A second direction 15 a is also shown by a dashed arrow, which points towards the positive x-direction 8 and thus towards the active region 18 .

[0076] Compared with the partition 2a according to FIG. 2A, the first direction 14a and the second direction 15a are Figure 3B The separator 300a forms an angle of at least 100 degrees, in particular 180 degrees. The same is true for the passage 13b passing through the sealing bead 12b, which leads to the outside of the bipolar plate 300, that is, on the separator 300b, which faces away from Figure 3A , 3B As a result of this orientation of the through opening 13a of the partition 300a, for example, the medium flowing from the through opening 11a through the through opening 13a to the active area can experience considerable changes in its flow direction (in Figure 3B 180 degrees in the middle) and can therefore be preferably distributed on the active area 18. In this way, for example, the distribution or collection area 20 can be formed to have a smaller surface area, and the active area 18 can be formed to have a larger surface area. As a result, the efficiency of the electrochemical system 1 including the bipolar plate 300 can be improved. FIG. 3A to FIG. 3C On the partition 300a, the passage 13a is fluidically connected to the active area 18, in particular by means of channels defined by the sealing flanges 12a-d, for example, by means of the channel 23 between the sealing flanges 12a and 12d, by means of the channel 24 between the sealing flanges 12a and 12c, by means of the channel 25 between the sealing flange 12c and the peripheral flange 12d, by means of the channel 26 between the sealing flanges 12b and 12c, and by means of the channel 27 between the sealing flange 12b and the peripheral flange 12d. Figure 3C The passage 23 between the sealing bead 12c and the peripheral bead 12d is also shown in the cross-sectional view in FIG. 1 , wherein no dedicated reference numeral is provided for each bipolar plate.

[0077] Similar to Figure 2B, Figure 3C The portion of the cross-sectional view shown in FIG. 1 may continue to the left in the area extending to the left of the flange 12 a, i.e., the walls of the bipolar plate defining the channels 23 to 26 (similar to the flanges 12 a to 12 d, the passages 13 a, 13 a ′, 13 a ″, and the walls of the channels defining the flow field 17) are molded directly into one of the separators of the bipolar plate. Therefore, the bipolar plate does not require any separately produced sealing elements or the like to be attached to the plate.

[0078] Figure 4A top view shows details of a bipolar plate 400 of the type provided by the present application according to a second embodiment. Figure 4 The bipolar plate 400 is based on FIG. 3A to FIG. 3C For simplicity, only the differences between the bipolar plates 300 and 400 are mainly highlighted hereinafter.

[0079] Similar to the bipolar plate 300, the bipolar plate 400 is also completely formed by two bonded metal separators 400a, 400b, wherein: Figure 4 The separator 400b in the bipolar plate 400 is blocked by the separator 400a. The bipolar plate 400 also includes a passage 13a passing through the sealing flange 12a, which is arranged on the side of the through opening 11a or the sealing flange 12a facing away from the active area 18 of the bipolar plate 400. In addition to the passage 13a, the first direction 14a includes an angle α1 of 180 degrees with the second direction 15a, similar to the bipolar plate 300, but compared with the bipolar plate 300, the bipolar plate 400 also includes a passage 13a, wherein the first direction 14a' includes a slightly smaller angle α2 of about 135 degrees with the second direction 15a. Figure 4 In the embodiment, this is the passage 13a arranged on the far left through the sealing bead 12a.

[0080] In addition, according to Figure 4 The bipolar plate 400 is based on FIG. 3A to FIG. 3C The bipolar plate 300 also differs in the shape of the through-openings 11a-c, which in the case of the bipolar plate 400 is a trapezoidal or substantially trapezoidal shape, wherein the parallel extending edges of the through-openings 11a-c are each oriented parallel to the y-direction 9 and therefore transversely or perpendicularly to the longitudinal direction of the bipolar plate 400.

[0081] The through opening 11c may be, for example, Figure 1 A portion of a coolant circuit of a system 1 comprising a bipolar plate 400, the cross section of the through opening 11c being determined parallel to the plane of the planar surface of the bipolar plate and along the y direction 9, and which increases continuously along the x direction 8 from the end of the through opening 11c facing away from the active area 18 towards the end of the through opening 11c facing the active area 18. Taking into account the radii of the transition between the lateral edges of the through opening, the cross section increases strictly monotonically at least in the region along a straight line running parallel to the entire medium flow direction 50 of the active area, between approximately 5% and 95% of the extension of the first through opening towards the active area, and therefore also between 60% and 90% of this extension, i.e. between the two dashed-dotted lines. In this way, a better supply of coolant to the bipolar plate 400 can be ensured. For example, compared with a comparable bipolar plate according to the prior art, and also with a bipolar plate according to the prior art. FIG. 3A to FIG. 3C Compared with the bipolar plate 300, according to Figure 4The flow cross-sections of all passages 13 c passing through the sealing ridge 12 c on the bipolar plate 400 are increased.

[0082] The cross section of each through-opening 11a, 11c, which is used, for example, to supply the electrochemical cells adjacent to the bipolar plate 400 with the reaction medium, is determined as a flat surface plane parallel to the bipolar plate 400 and in the y direction 9 and, apart from the end radius, increases continuously in the x direction 8 from the end of the through-opening 11a, 11c facing the active area 18 to the end of the through-opening 11a, 11c facing away from the active area. Taking into account the radii of the transition of the lateral edges of the through-openings into one another, the cross section decreases strictly monotonically, at least in the region along the flat straight line, which runs parallel to the overall medium flow direction 50 of the active area, between approximately 5% and 95% of the extension of the first through-opening to the active area, and therefore also between 10% and 40% of this extension, i.e. between the two dash-dotted lines. Thus, the side of the through opening 11a, 11b or the sealing bead 12a, 12b facing away from the active area 18 is longer on the bipolar plate 400 than on the bipolar plate 300 and can, for example, include a plurality of passages 13a, 13b. This can improve the supply of the reaction medium to the active area 18 and thus improve the efficiency of the electrochemical system 1 including the bipolar plate 400.

[0083] Another difference between the bipolar plate 400 and the bipolar plate 300 is that the distribution structures of the distribution or collection area 20 of the bipolar plate 400 parallel to the flat surface plane of the bipolar plate 400 each have an elongated cross section. This cross section may, for example, have a substantially rectangular, oval or other shape.

[0084] Figure 5 A top view shows details of a bipolar plate 500 of the type provided by the present application according to a third embodiment. Figure 5 The bipolar plate 500 is based on FIG. 3A to FIG. 3C For simplicity, only the differences between the bipolar plates 300 and 500 are mainly highlighted hereinafter.

[0085] Similar to the bipolar plate 300, the bipolar plate 500 is also formed by two bonded metal separators 500a, 500b, wherein: Figure 5 The partition 500b in the middle is blocked by the partition 500a. The angle α between the first direction 14a and the second direction 15a is again 180 degrees.

[0086] according to Figure 5 The bipolar plate 500 is based on FIG. 3A to FIG. 3CThe difference of the bipolar plate 300 is that the separator 500a includes an additional passage 28 around the through opening 11a and through the sealing ridge 12a. The passage 28 is oriented parallel to the y-axis 9. The passage 28 can further improve the supply of the reaction medium to the active area 18 or the discharge of the reaction medium from the active area.

[0087] Figure 6 A top view shows details of a bipolar plate 600 of the type provided by the present application according to a fourth embodiment. Figure 6 The bipolar plate 600 is based on Figure 4 For simplicity, only the differences between the bipolar plates 400 and 600 are mainly highlighted.

[0088] Similar to the bipolar plate 400, the bipolar plate 600 is also formed by two bonded metal separators 600a, 600b, wherein: Figure 6 The partition 600b in the figure is blocked by the partition 600a.

[0089] according to Figure 6 The bipolar plate 600 is based on Figure 4 The difference between the bipolar plate 400 of the present invention is that the separator 600a includes an additional passage 28 around the through opening 11a and through the sealing flange 12a, and an additional passage 29 around the through opening 11b and through the sealing flange 12b. The passages 28 and 29 are each oriented parallel to the y-axis 9. The passage 28 can further improve the supply of the reaction medium to the active area 18 or the discharge of the reaction medium from the active area 18. Therefore, the passage 29 can further improve the supply of the reaction medium to the active area of ​​the separator 600b and the discharge of the reaction medium from the active area of ​​the separator 600b. The angles α1 and α2 between the first direction 14a and the second direction 15a assigned to a specific passage 13a are obtained by means of Figure 6 Two of the passages 13a through the sealing bead 12a for the through opening 11a are highlighted. Figure 4 The bipolar plate 400, according to Figure 6 The angles α1 and α2 on the bipolar plate 600 are 180 degrees and approximately 135 degrees.

[0090] Figure 7 The top view shows details of a bipolar plate 700 of the type provided by the present application according to a fifth embodiment. Figure 7 The bipolar plate 700 is based on FIG. 3A to FIG. 3C For simplicity, only the differences between the bipolar plates 300 and 700 are mainly highlighted hereinafter.

[0091] Similar to the bipolar plate 300, the bipolar plate 700 is also formed by two bonded metal separators 700a, 700b, wherein: Figure 7 The partition 700b in the figure is blocked by the partition 700a.

[0092] according to Figure 7 The bipolar plate 700 is based on FIG. 3A to FIG. 3C The main difference of the bipolar plate 300 is the arrangement of the through openings 11a-c. In contrast to the bipolar plate 300, the through opening 11c in the bipolar plate 700 is arranged between the through openings 11a and 11b and the active area 18. The through opening 11c of the bipolar plate 700 may, for example, include Figure 1 The through openings 11a and 11b can be used to supply reaction gas to the electrochemical battery cells adjacent to the bipolar plate 700. FIG. 3A to FIG. 3C The bipolar plate 300 is opposite, according to Figure 7 The through opening 11c in the bipolar plate 700 extends along the y direction 9 over the entire width of the distribution or collection area 20 or over the entire width of the active area 18. This can improve the supply of coolant to the cavity 22 or the discharge of coolant from the cavity 22 via the through opening 11c. The angle α between the first direction 14a and the second direction 15a assigned to the passage 13a is obtained by means of Figure 7 The example of a passage 13a through the sealing bead 12a for the through-opening 11a is highlighted in FIG.

[0093] Finally, similar to Figure 4 The bipolar plate 400, according to Figure 7 The distribution structure of the distribution or collecting area 20 of the bipolar plate 700 has an elongated cross section parallel to the flat surface plane of the bipolar plate 700. However, the distribution structure of the distribution or collecting area 20 of the bipolar plate 700 may include projections and depressions, the projections pointing from the outside to the inside in the direction of the active area 18 based on the lateral edges of the bipolar plate 700, and the depressions pointing from the inside to the outside, wherein these depressions are mainly used to distribute the coolant through the cavity 22 on the rear side of the separator 700a facing the cavity 22, thereby ensuring uniform cooling as close to the active area 18 as possible.

[0094] Figure 8 The details of a bipolar plate 800 of the type provided by the present application according to the sixth embodiment are shown in a top view. Figure 8 The bipolar plate 800 is based on Figure 7 For simplicity, only the differences between the bipolar plates 800 and 700 are mainly highlighted.

[0095] Similar to the bipolar plate 700, the bipolar plate 800 is also formed by two bonded metal separators 800a, 800b, wherein: Figure 8 The partition 800b in the figure is blocked by the partition 800a.

[0096] according to Figure 8 The bipolar plate 800 is based on Figure 7 The bipolar plate 700 of the present invention is different in that two separate through-openings 11c are provided between the through-openings 11a, 11b and the active area 18, each of which is surrounded by a sealing ridge 12c and is fluidically connected to the cavity 22 enclosed by the separators 800a, 800b by means of a passage 13c passing through a specific sealing ridge 12c. Compared with the bipolar plate 700 in which only a single through-opening 11c is provided (which extends along the y direction 9 over the entire distribution or collection area 20 or the active area 18), the bipolar plate 700 may have the advantage that the reaction medium flowing between the through-opening 11a and the active area 18 can also flow through the channel 30 in the middle part of the separator 800a, which is defined by two separate sealing ridges 12c. The reaction medium flowing from the through-opening 11a to the active area 18 can thus be further improved, or the collection of the reaction medium flowing from the active area 18 to the through-opening 11a can be further improved.

Claims

1. A separator (300a, 400a, 500a, 600a, 700a, 800a) for an electrochemical system (1), the separator comprising: at least one first through opening (11a) for guiding the reaction medium through the partition (300a, 400a, 500a, 600a, 700a, 800a); an active area (18) comprising structure for directing a reaction medium along the flat sides of the separators (300a, 400a, 500a, 600a, 700a, 800a); and A first sealing structure (12a), the first sealing structure surrounding the first through opening (11a) and used for sealing the first through opening (11a); The first sealing structure (12a) comprises a first passage (13a) for guiding the reaction medium through the first sealing structure (12a). The first passage (13a) comprises a first passage opening (13a') facing away from the first through-opening (11a), The first passage (13a) defines a first direction (14a) leading from the first through-opening (11a) towards the first passage opening (13a'); and The first through opening (11a) is fluidically connected to the active area (18) by means of the first passage (13a), It is characterized in that The first passage (13a) is arranged and formed so that the first direction (14a) forms an angle of at least 100 degrees with a second direction (15a), the second direction (15a) being defined by a shortest straight connecting line connecting a first passage opening (13a') of the first passage (13a) to a medium inlet or outlet (16) of the active area (18), and the second direction (15a) is directed from the first passage opening (13a') of the first passage (13a) to the medium inlet or outlet (16) of the active area (18).

2. The partition (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1, characterized in that: The first passage (13a) has a second passage opening (13a") facing the first through-opening (11a), and the first direction (14a) is defined by the shortest straight through-line connecting the second passage opening (13a'') to the first passage opening (13a').

3. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The first passage (13a) is arranged and formed such that the first direction (14a) forms an angle with the second direction (15a), the angle being at least 105 degrees.

4. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The first passage (13a) is arranged and formed such that the first direction (14a) forms an angle with the second direction (15a), the angle being at least 110 degrees.

5. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The first passage (13a) is arranged and formed such that the first direction (14a) and the second direction (15a) together form an angle of at least 120 degrees.

6. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The invention comprises at least one second through-opening (11c) for guiding a coolant or a reaction medium to pass through the partition (300a, 400a, 500a, 600a, 700a, 800a), and comprises a second sealing structure (12c) surrounding the second through-opening (11c) for sealing the second through-opening (11c).

7. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 6, characterized in that: The partitions (300a, 400a, 500a, 600a, 700a, 800a) are formed of metal.

8. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 6, characterized in that: The partitions (300a, 400a, 500a, 600a, 700a, 800a) are formed of stainless steel.

9. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 7, characterized in that: The first sealing structure (12a) and / or the second sealing structure (12c) are formed as a plurality of sealing ridges pressed into the partition (300a, 400a, 500a, 600a, 700a, 800a), or are formed as a sealing ridge pressed into the partition (300a, 400a, 500a, 600a, 700a, 800a).

10. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 7, characterized in that: The structure of the active area (18) for guiding the reaction medium is embossed into the partition (300a, 400a, 500a, 600a, 700a, 800a).

11. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The invention comprises a distribution area (20) arranged between the first through opening (11a) and the active area (18), wherein the first passage opening (13a') of the first passage (13a) is fluidically connected to the active area (18) by means of the distribution area (20), and the distribution area (20) comprises a distribution structure configured to distribute the reaction medium on the active area (18), the reaction medium travels from the first passage opening (13a') of the first passage (13a) and is introduced into the distribution area (20), and / or is configured to collect / collect the reaction medium traveling from the active area (18) and flowing toward the first passage opening (13a') of the first passage (13a).

12. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The separator is formed from only one layer of metal sheet.

13. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1 or 2, characterized in that: The separator is formed from only one layer of stainless steel plate.

14. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1, characterized in that: The first passage opening (13a') is formed as a through-going window in the partition (300a, 400a, 500a, 600a, 700a, 800a).

15. The separator (300a, 400a, 500a, 600a, 700a, 800a) according to claim 1, characterized in that: The first passage opening (13a') is formed as a through hole in the partition (300a, 400a, 500a, 600a, 700a, 800a).

16. A bipolar plate, comprising a first separator (300a, 400a, 500a, 600a, 700a, 800a) of the separator structure according to any one of claims 7 to 15, comprising a second separator (300b, 400a, 500b, 600b, 700b, 800b) made of a metal plate, wherein: The first separator (300a, 400a, 500a, 600a, 700a, 800a) and the second separator (300b) are connected to each other, the second separator (300b) also includes a first through-opening, the first through-opening is aligned with the first through-opening (11a) of the first separator (300a, 400a, 500a, 600a, 700a, 800a), and the first through-openings of the first separator (300a, 400a, 500a, 600a, 700a, 800a) and the second separator (300b, 400a, 500b, 600b, 700b, 800b) aligned with each other form the first through-opening of the bipolar plate.

17. The bipolar plate according to claim 16, characterized in that: The second partition plates (300b, 400a, 500b, 600b, 700b, 800b) are made of stainless steel plates.

18. The bipolar plate according to claim 16, characterized in that: The second separator (300b, 400a, 500b, 600b, 700b, 800b) is formed of only one layer of metal plate.

19. The bipolar plate according to claim 16, characterized in that: The second separator (300b, 400a, 500b, 600b, 700b, 800b) is formed of only one layer of stainless steel plate.

20. The bipolar plate according to any one of claims 16 to 19, characterized in that The first partition (300a, 400a, 500a, 600a, 700a, 800a) is formed according to claim 6, the second partition (300b, 400a, 500b, 600b, 700b, 700b, 800b) also comprises a second through-opening, the second through-opening is aligned with the second through-opening (11c) of the first partition (300a, 400a, 500a, 600a, 700a, 800a), the first partitions (300a, 400a, 500a, 600a, 700a, 800a) being aligned with each other. , 700a, 800a) and a second separator (300b, 400a, 500b, 600b, 700b, 800b) form a second through opening of the bipolar plate, the first separator (300a, 400a, 500a, 600a, 700a, 800a) and the second separator (300b, 400a, 500b, 600b, 700b, 800b) enclose a cavity (22) for guiding a coolant through the bipolar plate, and the cavity (22) is fluidically connected to the second through opening (11c) of the bipolar plate.

21. The bipolar plate according to claim 20, characterized in that: The fluid connection between the second through-opening (11c) of the bipolar plate and the cavity (22) opens into the second through-opening (11c) of the bipolar plate on a side of the second through-opening (11c) of the bipolar plate facing the active area (18).

22. The bipolar plate according to claim 20, characterized in that: The cross section of the second through-opening (11c) of the bipolar plate is determined to be parallel to the flat surface plane of the bipolar plate, and the cross section of the second through-opening (11c) of the bipolar plate increases toward the active area (18) at least in an end section of the second through-opening (11c) of the bipolar plate facing the active area (18).

23. The bipolar plate according to claim 22, characterized in that: The second through opening in the active area (18) parallel to the overall medium flow direction (50) has a maximum diameter, and its first end faces the active area. The above-mentioned cross section of the second through opening is determined to be perpendicular to the maximum diameter of the second through opening. The above-mentioned cross section has a first end facing the active area and a second end away from the active area in a continuous section of the maximum diameter of the second through opening that always strictly increases monotonically toward the active area. The first end of the continuous section is at a distance of 10% of the length of the maximum diameter of the second through opening from the first end of the maximum diameter of the second through opening, and the second end of the continuous section is at a distance of 40% of the length of the maximum diameter of the second through opening from the first end of the maximum diameter of the second through opening.

24. The bipolar plate according to any one of claims 21 to 23, characterized in that A cross section of the first through-opening (11a) of the bipolar plate, which is defined parallel to the planar surface plane of the bipolar plate, increases in a direction away from the active area (18) at least in an end section of the first through-opening (11a) facing away from the active area (18).

25. The bipolar plate according to claim 24, characterized in that: The first through opening in the active area (18) parallel to the overall medium flow direction (50) has a maximum diameter, and its first end faces the active area. The above-mentioned cross section of the first through opening is determined to be perpendicular to the maximum diameter of the first through opening. The above-mentioned cross section of the first through opening, in a continuous section of the maximum diameter of the first through opening that always strictly increases monotonically in the direction away from the active area, has a first end facing the active area and a second end away from the active area. The distance between the first end of the continuous section and the first end of the maximum diameter of the first through opening is 60% of the length of the maximum diameter of the first through opening, and the distance between the second end of the continuous section and the first end of the maximum diameter of the first through opening is 90% of the length of the maximum diameter of the first through opening.

26. The bipolar plate according to claim 24, characterized in that The first through-opening (11a) of the bipolar plate and the second through-opening (11c) of the bipolar plate are arranged close to each other in a direction oriented transversely to the direction of the shortest straight connecting line between the first through-opening and the active area (18).

27. The bipolar plate according to claim 26, characterized in that: The second through-opening (11c) of the bipolar plate is arranged between the first through-opening (11a) of the bipolar plate and the active area (18).

28. An electrochemical system (1) comprising a plurality of separators (300a, 400a, 500a, 600a, 700a, 800a) according to any one of claims 1 to 15 or a bipolar plate according to any one of claims 16 to 27, and comprising a membrane assembly (19) arranged between the separators (300a, 400a, 500a, 600a, 700a, 800a) or between the bipolar plates.

29. The electrochemical system (1) according to claim 28, which is formed as a fuel cell stack or an electrolyzer, characterized in that: The membrane modules (19) each include at least one electrolyte membrane.

30. The electrochemical system (1) according to claim 28, which is formed as a humidifier, characterized in that The membrane modules (19) each include at least one water exchange membrane.

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