Separator plate for an electrochemical system

Abstract

The invention relates to a separator plate for an electrochemical system, in particular a fuel cell system.

Description

The invention relates to a separator plate for an electrochemical system, in particular a fuel cell system. Known electrochemical systems usually comprise a plurality of separator plates, which can in particular be designed as bipolar plates, each composed of two individual plates. The separator plates are typically arranged in a stack, so that each two adjacent separator plates enclose an electrochemical cell. The separator plates can serve, for example, to electrically contact the electrodes of the individual electrochemical cells (e.g., fuel cells) and / or to electrically connect adjacent cells (series connection of the cells). The separator plates can also serve to dissipate heat generated in the cells between the separator plates. Such waste heat can arise, for example, during the conversion of electrical or chemical energy in a fuel cell. Typically, the separator plates each have at least one through-hole. In the separator plate stack of the electrochemical system, the through-holes of the stacked separator plates, which are aligned or at least partially overlapping, form media channels for media supply or media removal. The separator plates may also have channel structures for supplying an active area of the separator plate with one or more of the media and / or for removing media. The separator plate typically comprises a so-called flow field, which forms the active area of the separator plate, as well as at least one distribution area that fluidically connects a through-opening to the flow field. Depending on the flow direction—out of or into the flow field—the distribution area can also be referred to as a collection area or have a fluid-collecting function. In the following, the term "distribution area" includes both a possible fluid-collecting function and a possible function of distributing the fluid across the flow field. By means of the distribution region, the fluid, which typically exits the through-opening along a comparatively small edge region, can be introduced into the flow field (or vice versa). The latter typically has a significantly larger inlet area for the fluid compared to the edge region of the through-opening. This inlet area can, for example, extend along more than half a width dimension of the separator plate. In order to successfully fluidly connect the aforementioned differently sized areas or sections of the through-opening and the flow field, whereby these areas or sections are generally not aligned centrally with one another, the fluid-conducting structures and, in particular, channels of the distribution region must be suitably aligned. To date, this has typically resulted in different channel lengths within the distribution region. As explained in more detail below, the different channel lengths are particularly pronounced in distribution areas that have an at least approximately triangular base area. For deviating and, in particular, essentially rectangular distribution areas, such as those known from WO 2023 245 713 A1, the channel lengths cannot vary to a comparable extent. It is generally desirable to further improve the efficiency of electrochemical systems. The present application is accordingly directed to this task, particularly in connection with distribution regions with significantly different channel lengths, such as the aforementioned at least approximately triangular distribution regions. According to the invention, it was recognized that there is potential for efficiency improvement in existing separator plates, particularly in connection with the passage of the fluid through the at least one distribution area. More specifically, it was recognized that the previously typically different channel lengths of the distribution area are accompanied by different, and more precisely, channel-specific, mass flows when flowing through the distribution area. Thus, flows are also generated in the flow field through the channels present there, with a correspondingly different mass flow, depending on which channel of the distribution area the channels of the flow field are fluidically connected to. These previously significantly different mass flows arise in particular because the number of channels in the flow field that are fluidically connected to a respective channel in the distribution area and, in particular, are located opposite it, is essentially constant. In other words, in previous solutions, a predominant number of channels in the distribution area, regardless of their respective length, each supply an equal number of channels in the flow field with fluid from the through-opening (or vice versa). The present invention, however, is based in particular on the finding that this ratio of channels that are fluidically connected to one another can be used as a degree of freedom to reduce the difference between the mass flows of the channels as they flow through the distribution area and / or the flow field.In particular, it can be provided that channels of the distribution area with a comparatively short length and thus a higher mass flow are fluidly connected to a higher number of channels of the flow field than channels of the distribution area with a comparatively long length and thus correspondingly lower mass flows. This can be achieved structurally by the inhomogeneous spacing between webs of the distribution area disclosed here. In particular, the invention proposes a separator plate for an electrochemical system, comprising:- at least one through-opening for conducting a fluid through the separator plate,- at least one distribution region having a plurality of first channels and first webs formed between each two first channels,- at least one flow field which is in fluid communication with the through-opening via the distribution region and which has a plurality of second channels and second webs formed between each two second channels,wherein first ends of the first webs are opposite ends of the second webs and / or merge into ends of at least selected ones of the second webs,wherein first distances between the respective first ends of mutually adjacent first webs are inhomogeneous. As is generally customary, the distances between the ends of the second webs facing the distribution area and / or at least partially merging into the webs there can be homogeneous. At least these distances can vary less than the first distances between the first ends of the distribution area webs. As explained below, the considered distances can be viewed in the width direction of the separator plate and / or orthogonal to a flow direction (see main flow direction below) through the flow field. Due to the inhomogeneous first distances, the channel width in the region of the first ends can be varied. Additionally or alternatively, the number of channels in the flow field that are at least predominantly or exclusively supplied with fluid by a respective channel of the distribution region, or into which they predominantly or exclusively introduce fluid, can be varied. This can be used to vary this number according to the expected mass flows of the distribution region channels. The larger the mass flows, the more channels in the flow field are preferably fluidically connected to a channel of the distribution region and / or are located opposite it. According to the above, in particular only the first distances between those first webs which border on both sides of a channel or which are arranged between two channels can be considered. In other words, according to a further embodiment, the first ends of the first webs can be distributed along a width axis of the separator plate, and the distribution region can have a first outermost first web and a second outermost first web, viewed along the width axis, wherein inner first webs are arranged between these two outermost first webs, and wherein, for the inner first webs, first distances between the respective first ends of adjacent first webs are inhomogeneous. The respective distances of the outermost webs to an outermost contour delimiting the distribution region can deliberately not be considered here. This takes into account the fact that in the prior art, the distances between the inner first webs are usually homogeneous, although it has been recognized according to the invention that there is great potential for efficiency improvements, particularly in connection with these inner first webs. The separator plate can be characterized by a longer dimension along a longitudinal axis and a shorter dimension along a width axis that runs orthogonal to the longitudinal axis. For example, the separator plate can have a rectangular shape or, in other words, a rectangular footprint, each with a correspondingly shorter and a longer dimension. The width axis or width dimension can extend orthogonally to a main flow direction through the flow field. This main flow direction can generally be predetermined by the orientation of the channels and / or webs of the flow field. For example, the main flow direction can run parallel to the longitudinal axes of the channels and / or webs or coincide with such a longitudinal axis. In the case of undulating flow fields, the main flow direction corresponds to the macroscopic flow direction, neglecting amplitudes on both sides.Additionally or alternatively, the width axis or an axis parallel thereto may be oriented such that it is opposite to, extends along, and / or intersects the first ends of the first webs and / or the ends of the second webs. The opposing arrangement of webs and / or channels can generally be understood to mean that, at the latest, these structures merge into one another or are aligned with one another when viewed virtually along extensions of the webs and / or channels and / or along a respective longitudinal axis. Additionally or alternatively, a fluid guided in one channel can be guided into an opposite channel along, for example, a straight or curved flow path and / or along a flow path that corresponds to an extension of the respective channel longitudinal axes. According to a further embodiment, the separator plate further comprises a transition region in which the first ends of the first webs are opposite the ends of the second webs and / or in which the first ends of the first webs merge into the ends of at least selected second webs, wherein the transition region is lowered relative to the flow field and / or the distribution region with respect to a height axis running perpendicular to a plane of the separator plate's flat surface. In particular, the maximum height of the transition region, in particular of the webs in the transition region, can be considered in comparison to the average maximum heights of the webs of the distribution region and the flow field, wherein this maximum height can be lower relative to these average maximum heights.Such a lowered transition area provides a free space for accommodating additional components, such as the overlap area of a reinforcing edge of a membrane electrode assembly (MEA). In a manner known per se, the plane of the flat surface can be defined, for example, by an edge of a separator plate and / or by those flat areas that are not deformed as a result of a stamping or deep-drawing process, for example to form the web-channel structures or beads described herein. According to a further embodiment, the fluid flows in the flow field along a main flow direction, to which all of the above explanations can apply, and: - the first webs and / or first channels each run at an angle to this main flow direction, i.e. at an angle different from 0°, and / or - a virtual connecting line of the first ends of the first channels runs substantially orthogonal to the main flow direction or at least at an angle of more than 75° and less than 105°, and / or - the distribution region extends along an entire width of the flow field, wherein the width is measured orthogonal to the main flow direction and / or along a width axis of the separator plate explained above, and / or - the first distances are measured orthogonal to the main flow direction.Alternatively, the first distances can be measured orthogonally to the longitudinal axis of a second channel enclosed by the two adjacent webs. In principle, the inhomogeneous web spacing and resulting inhomogeneous channel widths can occur along the entire width of the flow field. If a wave-shaped connecting line results between the first ends of the first channels, the virtual connecting line can, for example, be the connecting line of the wave crests pointing away from the flow field as far as possible. According to a further embodiment, the distances between the respective ends of adjacent second channels are homogeneous or at least less inhomogeneous than the first distances. Alternatively or additionally, the number of first channels is fewer than the number of second channels, wherein, in particular, the number of first channels is no more than half or no more than one-third as large as the number of second channels. It has been shown that these measures can achieve the desired efficiency improvement particularly reliably. According to a further embodiment, the first ends of the first webs are distributed along a width axis of the separator plate, and the distribution region has, viewed along the width axis, a first outermost first web and a second outermost first web. These can enclose and / or surround further first webs located inside them. The first outermost first web, and in particular its first end, can be positioned closer to the through-opening than the second outermost first web, and in particular its first end. The distances can be measured along or parallel to a plane and / or surface of the separator plate. For example, the shortest straight lines connecting the corresponding first webs, and in particular their first ends, to the through-opening and in particular to a fluid outlet region and / or a geometric center thereof can be considered. Viewed along the width axis and from the first outermost first web in the direction of the second outermost first web, the first distances can decrease and / or not increase at least in sections. Additionally or alternatively, along the width axis in the opposite direction, i.e. viewed from the second outermost first web in the direction of the first outermost first web, the first distances can increase at least in sections. For example, within the first half of a distance from the first outermost first web to the second outermost first web, the first distances can be higher, at least on average, than within the second half of this distance. By providing appropriately distributed distance inhomogeneities, mass flow differences that would otherwise occur can be at least partially compensated for and the operating efficiency of the electrochemical system can be improved. Additionally or alternatively, the channel lengths in the distribution area, viewed along the path from the first outermost first web to the second outermost first web, can increase at least in sections and / or not decrease and / or be at least on average longer within a first half than within the second half. In particular, the second outermost first web can be the longest first web. The distance inhomogeneities described above can represent efficiency-enhancing compensations for this channel length distribution. A further development provides that a maximum first distance exists at least between the first outermost first web and a further first web directly adjacent thereto, which can be a correspondingly inner web, and / or that a minimum first distance exists at least between the second outermost first web and a further first web directly adjacent thereto, which can be a correspondingly inner web. Within the scope of this disclosure, outermost structures bounding the distribution area that are not enclosed by channels on both sides and / or border channels on both sides cannot be considered first webs of the distribution area. This applies, for example, to plateau surfaces and / or sealing beads bounding the distribution area, each of which typically borders only a single outermost channel of the distribution area. According to a further embodiment, each first channel is configured to supply fluid to or receive fluid from at least one associated second channel, wherein the number of second channels associated with a respective first channel is inhomogeneous. In particular, the number of second channels associated with each of the first inner channels arranged between two inner first webs can be inhomogeneous. According to a further embodiment, a respective width of the first webs is constant or varies by no more than 20% along a respective length of a first web; and / or the respective widths of the first webs are identical and / or differ from one another by no more than 20%. However, the mean and / or maximum and / or minimum widths of the first channels, for example, may differ from one another—in particular due to the inhomogeneous spacing of the first webs disclosed here. Additionally or alternatively, the widths of at least selected first channels may vary along their respective length, in particular by at least 10% and / or at least 20%. The above measures have proven advantageous for achieving efficient fluid flow in the distribution area. For example, they allow for the formation of comparatively narrow webs and the use of the available installation space for a corresponding cross-sectional widening of the channels. According to a further embodiment, the first webs and / or the first channels are essentially kink-free and / or essentially curvature-free over at least two-thirds of their length. This can be understood, for example, to mean that any angles along the course of the first webs and / or first channels do not exceed 20°. In particular, the first webs and / or first channels can run in a straight line over at least two-thirds of their length. In particular, in the case of first webs that transition into second webs, the first webs can have a curvature in a region that is closer to the second webs than to the associated through-opening.It is preferred if all first webs of a distribution region have a curvature pointing in the same direction. Advantageously, the radius is positioned such that it points away from both the flow field and the side edge of the separator plate closest to the through-opening fluidically connected to this distribution region. Additionally or alternatively, the first webs may run non-parallel to one another along at least half of their length. In this way, the spacing inhomogeneity of the first ends disclosed here can be implemented in a structurally compact manner, and the available installation space can be utilized to form correspondingly wide flow cross-sections of the channels. According to a further embodiment, the first webs are no more than five times, preferably no more than four times, and in particular no more than three times as wide as the second webs. Additionally or alternatively, the first channels, at least in the middle third of their longitudinal extent, can be no more than eight times, preferably no more than six times, and in particular no more than five times as wide as the second channels. To determine the widths of webs and channels, the total height that the webs and channels together span perpendicular to the plane of the separator plate is first determined. Within the scope of this disclosure, a web width can then generally be determined as the maximum width of the area extending above half the height. A channel width, on the other hand, can be determined as the width of the area extending below half the height. This can enable a meaningful determination of the widths, for example, independent of any manufacturing radii. According to one variant, a width of at least some of the first channels decreases in the direction of the flow field. Alternatively or additionally, the width of at least some of the first channels can increase in the direction of the flow field. In particular, a combination can also be provided according to which the width of some first channels increases in the direction of the flow field and the width of some other of the first channels decreases in the direction of the flow field. It is also possible, particularly in the context of such a combination, that at least selected first channels are provided with a constant width. The above variants open up additional degrees of freedom to ensure efficient flow through the distribution area. According to a further embodiment, within the distribution region and / or within a region of the separator plate comprising the distribution region and at least one sealing bead adjacent thereto, a distance between regions of maximum height is no more than 5 mm and in particular no more than 3 mm. These regions of maximum height can form a contact surface for adjacent components of the electrochemical system. By limiting the distances between these regions, the size of regions of the separator plate in which no corresponding contact surfaces are present can be reduced. The adjacent sealing bead can in particular be a sealing bead that at least partially surrounds the through-opening and / or seals it. In a manner known per se, such a sealing bead can be locally perforated in order to provide a fluid connection between the through-opening and the distribution region. Preferably, the above spacing limits apply particularly in connection with the first outermost first webs or webs adjacent to the first outermost first channels, i.e., in areas with comparatively short first channels. These typically have wide channels, which, however, should not exceed the aforementioned spacing limits so that sufficient structural support can still be ensured. According to a further embodiment, second ends of the first webs can face the through-opening and be connected to one another by a virtual connecting line. This connecting line can be straight, but can also have a non-straight shape, for example a multiply or singly bent and / or curved shape. The through-opening can be configured along a first edge section for a fluid-conducting connection to the distribution area, for example by providing corresponding fluid channels and / or openings in an optionally circumferential sealing bead. The extension along the edge section does not require a constant distance from this edge section, although this can optionally be provided. In general, the extension along the edge section can include this extension deviating locally by no more than 90° and preferably no more than 45° from a direction of extension of the edge section. The first edge section can extend along at least one-third and in particular along at least half of the virtual connecting line. Figuratively speaking, this means that fluid exchange with the through-opening and thus with the media channel connected thereto is enabled over a correspondingly large area of the through-opening. This also enables a distribution of the second ends of the first webs along a correspondingly large area, which provides additional degrees of freedom for forming the extensions of, and spacings between, the first webs disclosed here. Additionally or alternatively, second ends of the first webs face the through-opening and are connected to one another by a virtual connecting line, wherein the virtual connecting line and an edge section of the through-opening, which may comprise an edge delimiting the through-opening, run at a constant distance from one another over at least half, preferably over at least 70% of their course. Only a portion of the edge section that lies opposite the second ends can be considered, thus the constant distance can be present along at least half or at least 70% of the course of this portion. Alternatively, only a portion of the edge of the through-opening that lies opposite the second ends of the first webs can be considered as the edge section. If the separator plate is divided into two halves along a dividing line running parallel to the main flow direction of the flow field, the second ends of the first webs of a distribution area are advantageously all arranged in the same half of the separator plate as the nearest through-opening, with which they are in direct fluidic communication. If the through-opening has a highly asymmetric shape, e.g., with projections, the half in which the majority of the through-opening area lies is relevant. According to a further development, the first channels and / or the first webs are at least five times, and in particular at least ten times, as long as they are wide. This preferably applies to at least 80% of the first channels and / or at least 80% of the first webs. Generally, within the scope of this disclosure, it can be provided that the webs are locally interrupted along their extension from the passage opening in the direction of the flow field (or vice versa), in particular by local depressions. Such interruptions can, for example, enable targeted crossflows between adjacent channels. Such depressions can divide the webs into different subsections. In such a case, a total length of the webs can also refer to the entire extension of the webs between their respective first and second ends and, in particular, include all possible subsections of a web. Furthermore, it may be advantageous if, for the second ends of the first webs, i.e., the ends opposite the through-opening, at least some of the distances between the respective second ends of adjacent first webs are homogeneous. The second ends can thus have the same distances and thus a comparable flow cross-section, even though the distances between the first ends are inhomogeneous. If the second ends of the first webs are distributed along a width axis of the separator plate and the distribution area, viewed along the width axis, has a first outermost first web and a second outermost first web, and if first inner webs are arranged between these two outermost first webs, it is advantageous if, for the inner first webs, the first distances between the respective second ends of adjacent first webs are homogeneous. The homogeneity of the second ends should therefore apply in particular to the first inner webs; any deviation of the outermost webs can be disregarded for this consideration. The invention also relates to a separator plate for an electrochemical system, comprising: - at least one through-opening for conducting a fluid through the separator plate, - at least one distribution region having a plurality of first channels and first webs formed between each two first channels, - at least one flow field that is in fluid communication with the through-opening via the distribution region, wherein second ends of the first webs are opposite the through-opening, wherein distances between the respective second ends of adjacent second webs are inhomogeneous. These distances correspond to the second distances disclosed here. In particular, in this context, the second ends of the first webs can be distributed along a width axis of the separator plate and the distribution area can have a first outermost first web and a second outermost first web viewed along the width axis, wherein inner webs are arranged between these two outermost first webs, and wherein for the inner first webs, distances between the respective second ends of mutually adjacent first webs are inhomogeneous. Advantageously, in any embodiment disclosed herein, the distribution region has a substantially and / or at least approximately triangular basic shape, wherein the triangle in particular forms an obtuse angle on the side opposite the flow field. The sides of this obtuse angle can merge directly into a triangular side line, in particular orthogonal to the main flow direction, or short transition sections can be present at one or both of these side ends, resulting overall in an asymmetrical quadrilateral or pentagonal shape. If the triangle, possibly obtained by approximation, is considered, it has the smallest angle at the corner facing the flow field, which is furthest from the through-opening fluidically connected to the flow field or the distribution region and adjacent to the latter. This angle can be between 7° and 40°. An approximately triangular shape can exist, for example, if there are three sides that together define at least 80% or at least 90% of the circumference of the distribution area. The sides can be inclined toward each other in the manner of a triangle and / or connected at their ends. In particular, one of the sides can connect the other two sides and be inclined toward each of them. The shape of the distribution region and in particular its substantially and / or at least approximately triangular shape can additionally or alternatively comprise the following: The distribution region and in particular its base area or basic shape, as given, for example, in a plan view of the separator plate, has a first side and a second side. The first side can be closer to the through-opening than the second side. The second side can be closer to the flow field than the first side. The first and second sides can be inclined towards one another and / or spaced from one another by the channels of the distribution region and / or enclose these channels between them, at least in sections. The first side can form or comprise a region via which fluid can enter the distribution region from the through-opening and / or vice versa.The second side may form or comprise a region through which fluid can enter the distribution region from the flow field, and / or vice versa. The first side may comprise the second ends of the first webs. The second side may comprise the first ends of the first webs. The first and second sides can be of different lengths. In particular, the length deviation can be at least 10%, in particular at least 25%, and furthermore in particular at least 50% or at least 75%. Additionally or alternatively, the length deviation can be no more than 150%, no more than 200%, or no more than 300%. Using the described length ratios, efficient flow conditions can be achieved and a deviation from rectangular distribution areas of the prior art can be achieved. In particular, when applying one of the mentioned length ratios, the first side can be shorter than the second side. The distribution region can further be at least partially delimited by at least one third side. In particular, the first and second sides can be connected to one another by this third side. The third side can extend along a longest channel and / or outermost web of the distribution region, in particular along the second outermost web disclosed herein. For example, it can directly adjoin such a web. The third side can comprise a length that deviates from the first and / or second side and is in particular longer than the first side. For example, the third side can be at least 10%, in particular at least 25%, and further in particular at least 50% or at least 75% longer than the first side. Additionally or alternatively, the length deviation can be no more than 150%, no more than 200%, or no more than 300%. In particular, by providing these three sides, which can each be inclined relative to one another, the at least approximately triangular shape of the distribution region can be achieved. Any of the first, second, and third sides can be at least approximately rectilinear. If a fourth side is also provided, which, for example, lies opposite the third side and accordingly borders on a first outermost web disclosed herein and / or extends parallel thereto, this fourth side can be significantly smaller than the third side. For example, the length of this fourth side can be no more than 10% of the length of the third side. In this case, in particular, the basic shape or base area of the distribution region can still be described as at least substantially triangular. If the basic shape or base area of the distribution area is considered to be quadrangular or even comprise multiple corners, at least selected opposing sides can be of different lengths and, for example, exhibit a length difference of at least 20% or even at least 50%. This applies in particular to a first side near the passage opening and a second side near the flow field. These can be defined analogously to the above-described first and second sides of an at least approximately triangular shape, particularly with regard to their length ratios. In summary, the shape of the distribution area can be described as at least approximately triangular or, if there are four or more corners, the described first and second sides can be of different lengths. According to the invention, it was therefore also recognized that fluid exchange with the through-opening offers potential for improvement with regard to the flow behavior of the distribution area, for which, in turn, the distances between adjacent webs and / or the associated channel widths can be appropriately adjusted. For example, channels along whose course reduced mass flows occur without further measures can have larger channel widths in the region of their second ends than channels in which comparatively larger mass flows occur. The width design of the channel ends can be based in particular on the results of simulation calculations. Any embodiments described herein concerning distances of the first ends of the first webs can be combined with any embodiments described herein concerning distances of the second ends of the first webs. Embodiments of the invention are explained below with reference to the attached schematic figures. The same reference numerals can be used for the same features across the figures. Within a respective figure, not all instances of a feature can be provided with the reference numeral assigned to this feature. Fig. 1 shows a perspective view of an electrochemical system, which in principle can comprise separator plates according to an embodiment of the invention. Fig. 2 shows perspective individual views of separator plates according to the prior art (SdT), which in principle can also be used in the electrochemical system from Fig. 1. Figs. 3A and 3B are schematically simplified partial views of a separator plate according to examples of the prior art. Fig. 4 is a schematically simplified partial view of a separator plate according to an embodiment of the invention. Fig.5 is a schematically simplified partial view of a separator plate according to a further embodiment of the invention. Fig. 6 is a schematically simplified partial view of a separator plate according to a further embodiment of the invention. Fig. 7 is a schematically simplified partial view of a separator plate according to a further embodiment of the invention. Fig. 8 is a schematically simplified partial view of a separator plate according to a further embodiment of the invention. Fig. 9 is a schematically simplified partial view of a separator plate according to a further embodiment of the invention. Fig. 10 is a diagram to illustrate inventive effects with regard to improved mass flow homogeneity in the distribution region. Fig. 1 shows an electrochemical system 1 with a plurality of identical metallic separator plates 2, which are arranged in a stack 6 and stacked along a z-direction 7. The separator plates 2 of the stack 6 are usually clamped between two end plates 3, 4. The z-direction 7 is also called the stacking direction. In the present example, the system 1 is a fuel cell stack. Two adjacent separator plates 2 of the stack 6 thus delimit an electrochemical cell, which serves, for example, to convert chemical energy into electrical energy. To form the electrochemical cells of the system 1, a membrane electrode assembly (MEA) 10 is arranged between each adjacent separator plates 2 of the stack 6 (see, for example, Fig. 2). The MEA 10 typically contains at least one membrane, e.g., an electrolyte membrane.Furthermore, a gas diffusion layer (GDL) can be arranged on one or both surfaces of the MEA 10. The MEA 10 also often includes a frame-shaped reinforcement layer that surrounds and reinforces the electrolyte membrane. The reinforcement layer is typically electrically insulating and prevents a short circuit from occurring during operation of the electrochemical system 1. In alternative embodiments, the system 1 can also be designed as an electrolyzer, an electrochemical compressor, or a redox flow battery. Separator plates 2 can also be used in these electrochemical systems. The structure of these separator plates can then correspond to the structure of the separator plates 2 explained in more detail here, even if the media conveyed on or through the separator plates in an electrolyzer, an electrochemical compressor, or a redox flow battery can differ from the media used in a fuel cell system. The z-axis 7, together with an x-axis 8 and a y-axis 9, spans a right-handed Cartesian coordinate system. The separator plates 2 each define a plate plane, wherein the plate planes can be flat surface planes of individual plates 2a, 2b (see Fig. 2 ) from which a respective separator plate 2 is composed, or wherein the plate planes can run at least parallel to such flat surface planes. The plate planes or flat surface planes are aligned parallel to the xy-plane and thus perpendicular to the stacking direction or to the z-axis 7. The end plate 4 generally has a plurality of media connections 5, via which media can be fed to the system 1 and via which media can be removed from the system 1, wherein the media connections 5 are sometimes referred to as ports. These media that can be fed to the system 1 and removed from the system 1 can, for example,Fuels such as molecular hydrogen or methanol, reaction gases such as air or oxygen, reaction products such as water vapor or depleted fuels, or coolants such as water and / or glycol. In an electrochemical system 1, as shown in Fig. 1, both known separator plates 2 according to the prior art and separator plates 2 according to the invention can be used. Fig. 2 shows a perspective view of two adjacent separator plates 2 according to prior art examples that can be used in an electrochemical system of the type of system 1 shown in Fig. 1. With the exception of the design of the distribution region disclosed herein and its fluid exchange with a flow field, the following statements regarding this separator plate 2 can also apply to separator plates 2 according to the invention of this disclosure. Fig. 2 also shows a membrane electrode assembly (MEA) 10 arranged between the adjacent separator plates 2 and known from the prior art, wherein the MEA 10 in Fig. 2 is largely concealed by the separator plate 2 facing the viewer. The separator plate 2 is formed from two materially joined individual plates 2a, 2b, of which only the first individual plate 2a facing the viewer is visible in Fig. 2, which conceals the second individual plate 2b. The individual plates 2a, 2b can each be made of a metal sheet, e.g., a stainless steel sheet. The individual plates 2a, 2b can, for example, be welded together along their outer edge, e.g., by laser welding. The individual plates 2a, 2b typically have aligned through-openings that form through-openings 11a-c of the separator plate 2. When a plurality of separator plates 2 are stacked, the through-openings 11a-c form lines or media channels that extend through the stack 6 in the stacking direction 7 (see Fig. 1). Typically, each of the lines formed by the through-openings 11a-c is in fluid communication with one of the ports 5 in the end plate 4 of the system 1. For example, coolant can be introduced into the stack 6 via lines formed by each of the through-openings 11a of the separator plates 2, while the coolant is discharged from the stack 6 via an opposite through-opening 11a. The lines formed by the through-openings 11b, 11c, on the other hand, can be designed to supply the electrochemical cells of the fuel cell stack 6 of the system 1 with fuel and reaction gas, as well as to discharge the reaction products from the stack 6. The media-carrying through-openings 11a-c are formed essentially parallel to a respective plate plane. To seal the through-openings 11a-c from the interior of the stack 6 and from the environment, the first individual plates 2a each have sealing beads 12a-c, which are arranged around the through-openings 11a-c and completely enclose the through-openings 11a-c. The second individual plates 2b have corresponding sealing beads on the rear side of the separator plates 2 facing away from the viewer of Fig. 2 for sealing the through-openings 11a-c (not shown). In an electrochemically active region 18, the first individual plates 2a have, on their front side facing the viewer in Fig. 2, a flow field 17 with structures 14 for guiding a reaction medium along the outer side (or front side) of the individual plate 2a. These structures 14 are provided in Fig. 2 by a plurality of webs and channels extending between the webs and delimited by the webs. On the front side of the separator plate 2 facing the viewer in Fig. 2, the first individual plates 2a also each have a distribution and / or collection region 20, which is referred to herein for simplicity only as distribution region 20. A transition region 21 with depressed webs can extend between the distribution regions 20 and the flow field 17 of the electrochemically active region. The distribution region 20 comprises structures configured to distribute a medium introduced from a first of the two through-openings 11c into the adjacent distribution region 20 via the flow field 17 and to collect or bundle a medium flowing from the flow field 17 toward the second of the through-openings 11c via the collection region 20. The distribution structures of the distribution and / or collection region 20 are also represented in Fig. 2 by webs and channels extending between the webs and delimited by the webs. The sealing beads 12a-12c are crossed by passages 13a-13c, which are each formed in all individual plates 2a, 2b and which enable fluid exchange with a respective associated through-opening 11a-11c. The following Figs. 3A / B to 9 each show partial views of separator plates 2, which, with the exception of the differences already mentioned, can be designed largely analogously to the example from Fig. 2. The views correspond to a plan view of one of the outer sides of a respective separator plate 2. The partial views do not show a complete surface or the outline of a respective separator plate 2. Also, not all of the through openings 11a-c analogous to Fig. 2 are shown, although they may nevertheless be present in a respective separator plate 2. 3A-B initially show further examples of separator plates 2 according to the prior art. These separator plates 2 have a substantially rectangular outline (not shown separately). They are characterized by a longitudinal axis L17, which runs along the larger dimension of the rectangular shape (not shown separately), and by a width axis B17, which runs along the smaller dimension of the rectangular shape (not shown separately). The partial views shown show two through-openings 11b, which are fluidically connected via two distribution regions 20 and a flow field 17 arranged between the distribution regions 20. The number of through-openings 11b shown is not limiting, and, as mentioned, further through-openings 11b, 11c can also be provided, for example, as shown in Fig. 2. The distribution regions 20 comprise, as fluid-conducting structures, a plurality of elongated first channels 22 as well as elongated first webs 24 each extending between two first channels 22. As shown in Fig. 3B and also in Fig. 5 using dash-dotted lines in the right-hand half of the figure, the distribution region is essentially triangular - bordered to the left by the double-dotted line - or has an asymmetrical pentagonal shape. The triangular leg opposite the through-opening 11b also corresponds to an approximate consideration here. At the corner facing away from the flow field, the triangle has an obtuse angle α in the range of 110-120°, specifically here it is approximately 105°, the smallest angle β is in the range of 25-35°, specifically here it is approximately 30°, and is spanned at the corner furthest from the through-opening 11b.In all examples - of the prior art shown as well as those according to the invention - the distribution areas do not have a rectangular or even approximately rectangular shape. Additionally or alternatively, the shape of a distribution region 20 can be described as follows. Each distribution region 20 comprises sides 100-106, as marked in Fig. 5 for one of the distribution regions 20, which at least partially define and / or delimit its extension and / or shape and / or circumference. These sides 100-106 can be arranged and / or connected to one another according to an at least approximately triangular shape. At least the first to third sides 100-104 explained below can also be referred to as first to third triangular legs. A first side 100, which can also be referred to as a first triangular leg, is located adjacent to the through-opening 11b and comprises the second ends 34 of the first webs 24 and first channels 22 explained below, as well as a virtual connecting line V', see Fig. 4 . A second side 102 comprises the first ends 32 of the first webs 24 and first channels 22 explained below as well as a virtual connecting line V, see Fig. 4 . The second page 102 is significantly longer than the first page 100 and, for example, is about twice as long. The first and second sides 100, 102 are connected by a third side 104, which extends along a longest channel 22 and a second outermost first web 24" explained below, see Fig. 4 . If the line 112 is considered as the boundary between the distribution region 20 and the flow field 17, two further, optional sides 106, 108 are shown, of which the first 106 is opposite the third side 104 and the second 108 is opposite the first side 102, but which are each significantly shorter than the third and first sides 104, 102, respectively. Therefore, these sides 106, 108 can also be approximately disregarded when describing the shape of the distribution region 20, i.e., one can speak of an essentially triangular shape instead of a pentagonal shape.This applies in particular if these sides 106, 108, as is the case in the example shown, occupy no more than 10% and in particular no more than 5% of the total circumference of the distribution area 20. Even assuming a quadrangular or pentagonal shape comprising the further side 106 or 108, however, the first and second sides 100, 102, as opposite sides, are significantly different in length. This also applies if the second side extends along a line comparable to line 112 and deviates from rectangular distribution areas of the prior art. The flow field 17 also includes, as fluid-conducting structures, a plurality of elongated channels, referred to as second channels 26, as well as a plurality of elongated webs, referred to as second webs 28. These correspond to the structures 14 in Fig. 2 . A main flow direction through the flow field 17, not separately shown, runs parallel to the longitudinal axis L17. In all Figs. 3A / B to 9, only selected ones of the channels 22, 26 and webs 24, 28 are provided with a corresponding reference numeral. Furthermore, in the description of all Figs. 3A / B to 9, reference may primarily be made to only one of the distribution regions 20 and, in particular, to its interaction with the flow field 17 and / or the adjacent through-opening 11b, although the same may apply to the other distribution region 20. In the examples of Figs. 3A-B, the through-openings 11b are again surrounded by a sealing bead 12b. This is provided with schematically indicated passages 13b in an edge section 30 facing an adjacent distribution area 20. The first webs 24 and first channels 22 of the distribution regions 20 run parallel to one another completely or at least over a large part of their lengths, but have different lengths. This results in particular from the off-center arrangement of the through-openings 11b relative to the flow field 17, for example, viewed along the width axis B. In order to be fluidically connected to a region of the flow field 17 that is distant from the viewpoint of the through-openings 11b, viewed along the width axis B17, the first channels 22 and first webs 24 leading to this distant region must be designed with a correspondingly increased length. In Fig. 3A, this applies, for example, to the upper first channels 22 and webs 24 of the left distribution region 20 and the lower first channels 22 and webs 24 of the right distribution region 20. The first webs 24 and first channels 22 of the distribution areas 20 each have first ends, of which those of the first webs 24 are designated by the reference numeral 32, and these first ends are opposite ends 29 of the second webs 28 and ends 27 of the second channels 26 of the flow field 17. Furthermore, the first webs 24 and first channels 22 each have second ends 34, which are opposite the through-opening 11b and, at least in most cases, the described passages 13b. From the first channels 22 immediately adjacent to the first ends 32 of the first webs 24, fluid flows from one of the distribution regions 20 into the flow field 17 or from the flow field 17 into one of the distribution regions 20. In the process, the fluid flows through a lowered transition region 36. In the example of Fig. 3A, the first webs 24 of the distribution areas 20 do not merge into the second webs 28 of the flow field 17, but remain at a distance therefrom. In the example of Fig. 3B, the first webs 24 of the distribution areas 20 each merge into a second web 28 of the flow field 17. Starting from a first web height in the distribution area 20, the webs decrease in the transition area 36, only to rise again towards the flow field 17, but only by a lesser amount. The number of second webs 28 and second channels 26 of the flow field 17 is higher than the corresponding number within the distribution areas 20. In both the case of Fig. 3A and the case of Fig. 3B, the distances A of the first ends 32 of the first webs 24 of the distribution regions 20 to a respective immediately adjacent first end 32 of another first web 24 are homogeneous. An exemplary distance A is shown in Fig. 3A. These distances A can be measured along the width axis B17 and thus orthogonal to the longitudinal axis L17 and / or a main flow direction through the flow field 17. Alternatively, these distances A can be measured orthogonal to the longitudinal axis of the first channel 22 that is delimited by the correspondingly spaced first webs 24. The second webs 28 of the flow field 17 are also constantly spaced apart from one another along the longitudinal axis L17. The constant distances A between the first and second webs 24, 28 result in correspondingly constant widths of the first and second channels 22, 26 formed between these webs 24, 28. In addition, the distances B between second ends 34 of the first webs 24 of the distribution areas 20 are also homogeneous. Furthermore, at least the plurality of respective first channels 22 of one of the distribution regions 20 are opposite the same number of, for example, four second channels 26 of the flow field 17. This is particularly clear from a view along a schematically plotted flow path S, which illustrates a distribution of the fluid from a respective first channel 22 to a plurality of first channels 26 of the flow field 17 (and vice versa). The above relates in particular to the inner first channels 22 and the inner first webs 24 delimiting them, which are arranged between outermost first channels 22' and outermost first webs 24', 24". This intermediate arrangement is present in particular when viewed along the width axis B17. A group I of the inner first channels 22 and inner first webs 24 is highlighted as an example for the right distribution area 20 from Fig. 3A, but is also present in the other distribution areas 20 of Fig. 3A-B. Because the first channels 22 of the distribution areas 20 have different lengths, inhomogeneous mass flows occur, at least after flowing through the distribution areas 20, in Fig. 3B, i.e., at the end 32 of the first webs of the left distribution area 20. These also affect the flow through the second channels 26 of the flow field 17, so that the flow through the flow field 17 can also exhibit corresponding inhomogeneities. It has been shown that this negatively affects the operational efficiency of the electrochemical system 1. In the following Figs. 4-9, in views analogous to Figs. 3A-B, exemplary embodiments are described to limit such efficiency losses. Reference will be made to the explanations for Figs. 3A-B as well as to Fig. 2, and these apply analogously in the context of Figs. 4-9, with the exception of the special features described. Modifications compared to Figs. 3A-B and Fig. 2 arise in particular with regard to the distribution regions 20, whereas the flow field 17 and the through-openings 11b are designed analogously to Figs. 3A-B. Fig. 4 shows a first embodiment in which not all of the first webs 24 of the distribution regions 20 run parallel to one another. Consequently, not all of the first channels 22 formed between the first webs 24 and delimited by them are the same width either. In particular, for at least some of the first channels 22, the channel widths increase in the direction of the flow field 17. This applies to at least the first five inner lower first channels 22 in the left distribution region 20 and along the width axis B17 in Fig. 4. Optionally, however, constant channel widths or decreasing channel widths can also be provided as they extend in the direction of the flow field 17, as shown for some of the upper first channels 22 of the left distribution region 20 in Fig. 4. As a result, the distances between the first ends 32 of the first webs 24 and in particular of the inner first webs 24 are inhomogeneous and decrease in Fig. 4 and with reference to the left distribution region 20 from vertically below to vertically above, at least on average. A virtual connecting line V of these first ends 32 is shown as an example. It can be seen in Fig. 4 that in a lower half H2 of the connecting line V, at least on average, there are significantly greater distances between immediately adjacent first ends 32 than in the upper half H1. Example distances A1, A2 within the respective halves H1, H2 are entered. In particular, there can be a minimum distance in the first half H1 and a maximum distance in the second half H2.At the same time, the first channels 22, which are delimited by those webs 24 to which the first ends 32 within the lower half H2 belong, are significantly shorter than the first channels 22 assigned to the upper half H1. In Fig. 4, a first outermost first web 24' and a second outermost first web 24" are marked. In the view of Fig. 4, the first outermost first web 24' is positioned in the left-hand distribution area below the second outermost first web 24". The first end 32 of the first or lower outermost first web 24' is positioned closer to the through-opening 11b immediately adjacent to the distribution area 20 than the first end 32 of the second or upper outermost first web 24". The first or lower outermost first web 24' has a greater and, in particular, a maximum distance from an immediately adjacent inner web 24 than the second or uppermost outermost first web 24" has from its immediately adjacent inner web 24. The latter outermost first web 24" has a minimum distance from its immediately adjacent inner web 24.The minimum and maximum distances each refer to the total of the distances A between the adjacent ends 32 of the first webs 24. The second outermost first web 24" is the longest first web 24 within a distribution area, and the first outermost web 24' is the shortest. The same applies to the channels 22 immediately adjacent to these webs 24', 24". One result of the described structure of the distribution region 20 is that the internal first channels 22 assigned to the lower half H2 are located, at least on average, opposite a larger and in particular a maximum number of second channels 26 of the flow field 17 than the first channels 22 assigned to the upper half H1. This means that the shorter, lower first internal channels 22, after flowing through which a higher mass flow results, are directly or predominantly fluidically connected to a larger number of second channels 26 of the flow field 17 than the comparatively longer first channels 22. This improves the flow behavior of the distribution region 20 and thus increases the efficiency during operation of an electrochemical system 1 comprising the separator plate 2. It should be noted that all first webs 24 and first channels 22 are elongated and significantly longer than they are wide. In the example shown in Fig. 4, they also run straight and without curvature. Furthermore, they each run at an angle to the longitudinal axis L17, along which a main flow direction through the flow field 17 also runs. The first webs 24 are also similarly wide and in any case not significantly wider than the second webs 28, for example, no more than three times as wide. Both the first and the second webs 24, 28 have a constant width in the example shown. Furthermore, the fluid is guided through the first channels 22 and from the through-openings 11b in a substantially identical direction relative to the longitudinal axis L17 or main flow direction to the flow field 17 (or vice versa). In the case of the lower left distribution region 20 in Fig. 4, this relates to a diagonal direction inclined toward the flow field 17. Furthermore, Fig. 4 clearly shows that the distribution region 20 extends across the entire width of the flow field 17 and, in particular, the first ends 32 are distributed across almost the entire width. Finally, Fig. 4 shows that the distances B between adjacent second ends 34 of the first webs 24 are also inhomogeneous in this example. Exemplary different distances B1, B2 are plotted. The second ends 34 are distributed along a virtual connecting line V'. This line runs almost along the entire edge section 30 of the through-opening 11b, in which the feedthroughs 13b are formed. In Fig. 4, the virtual connecting line V' runs straight and parallel to the edge section R of the through-opening 11b and parallel to a connecting line (not shown) through the openings 13b' of the feedthroughs 13b as well as to a macroscopic extension direction of the sealing element 12b running on this side of the through-opening 11b. Considering the ratios of the widths A1, A2 of the first channels 22 adjacent to the first ends 32 of the first webs 24 to the widths B1, B2 of the same first channels 22 adjacent to the second ends 34 of the first webs 24, A1 / B1 < A2 / B2 is here. In the first channel 22 considered, A1<B1 während im zweiten betrachteten ersten Kanal 22 A2> B2. On the one hand, there are a small number of first channels 22 which become narrower in their course from the edge section 30 to the transition area 36 and a larger number of first channels 22 which become wider along the same route, with most of the increases in width being significantly more pronounced than the decreases. The longitudinal axis L17 is shown in Fig. 4 such that it divides the separator plate 2 into two halves H1, H2. All second ends 34 of the first webs 24 are arranged in Fig. 4, as in the other embodiments, in the same plate half in which the through-opening 11b is located, with which the first channels 22 communicate directly fluidically. Fig. 5 shows a further embodiment which differs from the example in Fig. 4 primarily in that the first webs 24 each merge into a second web 28 of the flow field 17. Due to the higher number of channels and webs in the flow field 17 compared to the distribution regions 20, however, there are also webs 28 of the flow field 17 which do not merge into any of the first webs 24. The first webs 24 each run in a straight line over a large part of their length and are curved near their first ends 32 in the direction of the flow field 17 or away from its webs 28. The curvature of all webs points in the same direction. Their radius points towards the flow field 17 and away from the third side 104. Again, the distances A between the first ends 32 of adjacent first webs 24 vary analogously to the example in Fig. 4 , see the different distances A1, A2. The first ends 32 can be located in particular where the first webs 24 enter the transition region 36 or in the middle of this transition region 36. Again, the inhomogeneous distance A is associated with the fact that a different number of second channels 28 of the flow field 17 are opposite the first channels 22. Not shown, but nevertheless optionally provided, is also an inhomogeneity of the distances B between the second ends 34 of the first webs 24, explained with reference to Fig. 4. Fig. 6 shows an embodiment comparable to Fig. 4, in which the first webs 24 do not directly transition into second webs 28 of the flow field 17. Again, these first webs 24 are rectilinear and extend at an angle to the longitudinal axis L17. There are also inhomogeneous distances A1, A2 between the first ends 32 and between the second ends 34 of the first webs 22 (not shown). In contrast to the variant of Fig. 4, however, the webs 24 are locally interrupted, see the depressions 40. Furthermore, in this case, the distances between directly adjacent webs 24 and thus the channel widths decrease when one of the through openings 11b extends in the direction of the flow field 17. This embodiment further differs from that of Fig. 4 in that all channel widths decrease from the edge region 30 to the transition region 36, A <b gilt für das verhältnis a1 b1 ebenso wie a2 b2. fig. 7 zeigt eine zu 5 vergleichbare ausführungsform, bei der die ersten stege 24 jeweils in einen zweiten 28 des strömungsfeldes 17 übergehen. erneut sind diese geradlinig und verlaufen einem winkel längsachse l17. auch liegen inhomogene abstände a1, zwischen den enden 32 vor. zwischen 34 jeweiligen b1, b2 homogen. in dem gezeigten beispiel nehmen zumindest einigen benachbarten stegen somit daraus resultierenden kanalbreiten ausgehend von richtung abschnittsweise bis ab. es beiden genauer betrachteten kanäle 22 wieder>A1 and B2>A2. Only in the transition region does the width change in the opposite direction, increasing again in the direction of flow field 17. Figs. 4-7 illustrate - without being exhaustive examples, however - the design scope for achieving the spacing inhomogeneity according to the invention. Fig. 8 shows a further embodiment in which the distribution regions 20 are designed differently from one another. The distribution region 20 on the left in Fig. 8 is designed essentially analogously to the example from Fig. 4, but optionally with local depressions 40 in the first webs 24. The distribution region 20 on the right in Fig. 8, in contrast, is designed analogously to the example from Fig. 6. The two distribution regions 20 therefore differ in particular with regard to the number, length and orientation of the first webs 24, the entire length of which extends in the region of the height extension of the respectively adjacent through-opening 11b. One of the distribution regions 20 could also be designed according to an example of the prior art, i.e. both distribution regions 20 do not have to have the spacing inhomogeneity according to the invention. The latter can, however, be advantageous in order to increase the overall efficiency. Fig. 9 shows yet another embodiment in which the left distribution region 20 is designed similarly to the variant in Fig. 5, but has a higher number of webs and channels. The right distribution region 10 has the same number of webs and channels as the left distribution region 20, but differs from it in that none of the webs 24 of the right distribution region 20 directly merges into a web of the flow field 17. Such different designs can, for example, be due to the coolant guide in the interior of the separator plate 2. Furthermore, a fluid-conducting connection to a different through-opening 11c is shown compared to the previous Figs. 3A / B-B. This through-opening 11c can, analogous to the example in Fig. 2, be a through-opening 11c for the supply or removal of coolant.The discharge of fuel, reaction gas, and / or reaction products can be involved, whereby the media guided may differ from those of the through-opening 11b. Not only are the distribution regions 20 not point-symmetrical here, but also the through-openings 11c, which have different, approximately triangular shapes. It should be noted again that not all of the through-openings 11a-c of the separator plates 2 are shown in the schematic partial views of Figs. 3A / B-9, but they may be present there, analogous to the example in Fig. 2. Fig. 10 shows a diagram illustrating improved homogeneity of the mass flow halfway through the flow field 17 when flowing through a surface of a separator plate according to any of the embodiments of the invention disclosed here. Deviations from an average mass flow are plotted along the vertical diagram axis. The curves shown are only smoothed curves. From left to right, the channels of the flow field 17 of a point-symmetric separator plate 2 are shown, i.e., the horizontal direction corresponds, for example, to a view along the width axis B17 in Fig. 4, and positions in the horizontal direction correspond to positions of these channels along the width axis B17. The dashed line indicates values achieved with an embodiment according to the invention. The dotted line indicates values achieved with a separator plate according to the prior art. It can be seen that with the embodiment according to the invention, the fluctuations in the mass flow are reduced compared to the prior art. Thus, the dashed line runs over long distances at a smaller distance from the horizontal diagram axis 0.0% than the dotted line. As mentioned, the improved homogeneity of the mass flow according to the invention is accompanied by an overall improved and therefore efficiency-enhancing flow behavior of the distribution areas 20 and also of the flow field 17. QUOTES CONTAINED IN THE DESCRIPTION This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature WO 2023 245 713 A1

[0007]

Claims

[1] Separator plate (2) for an electrochemical system (1), comprising: - at least one through-opening (11a-c) for passing a fluid through the separator plate (2), - at least one distribution area (20) having a plurality of first channels (22) and first webs (24) formed between each two first channels (22), - at least one flow field (17) which is in fluid communication with the through-opening (11a-c) via the distribution region (20) and which has a plurality of second channels (26) and second webs (28) formed between each two second channels (26), wherein first ends (32) of the first webs (24) are opposite ends (29) of the second webs (28) and / or merge into ends (29) of at least selected ones of the second webs (28), wherein first distances (A) between the respective first ends (32) of mutually adjacent first webs (24) are inhomogeneous. [2] Separator plate (2) according to the preceding claim, wherein the first ends (32) of the first webs (24) extend along a width axis (B 17 ) of the separator plate (2) and the distribution area (20) along the width axis (B 17 ) has a first outermost first web (24') and a second outermost first web (24"), wherein inner first webs (24) are arranged between these two outermost first webs (24', 24"), and wherein for the inner first webs (24) first distances (A) between the respective first ends (32) of mutually adjacent first webs (24) are inhomogeneous. [3] Separator plate (2) according to one of the preceding claims, further comprising a transition region (36) in which the first ends (32) of the first webs (24) are opposite the ends (29) of the second webs (28) and / or in which the first ends (32) of the first webs (24) merge into the ends (29) of the at least selected second webs (28), wherein the transition region (36) is lowered relative to the flow field (17) and / or the distribution region (20) with respect to a height axis running perpendicular to a plane of the plane surface of the separator plate (2). [4] Separator plate (2) according to one of the preceding claims, wherein the fluid flows in the flow field (17) along a main flow direction and: - the first webs (24) and / or first channels (22) each extend at an angle to this main flow direction, and / or - a virtual connecting line (V) of the first ends (32) of the first channels runs substantially orthogonal to the main flow direction and / or - the distribution area (20) extends along an entire width of the flow field (17), the width being measured orthogonal to the main flow direction, and / or - the first distances (A) are measured orthogonal to the main flow direction. [5] Separator plate (2) according to one of the preceding claims, wherein the distances (A) between the respective ends (27) of mutually adjacent second channels (26) are homogeneous or at least less inhomogeneous than the first distances (A); and / or wherein the number of first channels (22) is less than the number of second channels (26), in particular wherein the number of first channels (22) is not more than half as large or not more than one third as large as the number of second channels (26). [6] Separator plate (2) according to one of the preceding claims, wherein the first ends (32) of the first webs (24) extend along a width axis (B 17 ) of the separator plate (2) and the distribution area (20) along the width axis (B 17 ) has a first outermost first web (24') and a second outermost first web (24"), wherein the first outermost first web (24') and in particular its first end (32) is positioned closer to the through-opening (11a-c) than the second outermost first web (24") and in particular than its first end (32), wherein - along the width axis (B 17 ) and viewed from the first outermost first web (24') in the direction of the second outermost first web (24"), the first distances (A) decrease at least in sections and / or - along the width axis (B 17) and viewed from the first outermost first web (24') in the direction of the second outermost first web (24"), the first distances (A) do not increase at least in sections and / or - along the width axis (B 17 ) and viewed from the second outermost first web (24") in the direction of the first outermost first web (24"), the first distances (A) increase at least in sections. [7] Separator plate (2) according to claim 6, wherein a maximum first distance (A) is present at least between the first outermost first web (24') and a further first web (24') directly adjacent thereto, and / or wherein a minimum first distance (A) exists at least between the second outermost first web (24") and a further first web (24) directly adjacent thereto. [8] Separator plate (2) according to one of the preceding claims, wherein each first channel (22) is adapted to supply fluid to or receive fluid from at least one associated second channel (26), wherein the number of second channels (26) associated with a respective first channel (22) is inhomogeneous, in particular the number of second channels (26) associated with a respective one of the respective first inner channels (24') arranged between inner first webs (24) is inhomogeneous. [9] Separator plate (2) according to one of the preceding claims, wherein a respective width of the first webs (24) is constant or varies by no more than 20% along a respective length of a first web (24); and / or wherein the respective widths of the first webs (24) are identical and / or do not differ from each other by more than 20%. [10] Separator plate (2) according to one of the preceding claims, wherein the first webs (24) are substantially kink-free and / or substantially curvature-free over at least two-thirds of their length. [11] Separator plate (2) according to one of the preceding claims, wherein the first webs (24) are non-parallel to one another along at least half of their length. [12] Separator plate (2) according to one of the preceding claims, wherein the first webs (24) are not more than five times, preferably not more than four times, in particular not more than three times as wide as the second webs (24). [13] Separator plate according to one of the preceding claims, wherein second ends (34) of the first webs (24) face the through-opening (11a-c) and are connected to one another by a virtual connecting line (V'), wherein the through-opening (11a-c) is arranged along a first edge section (30) for a fluid-conducting connection to the distribution area (20), wherein the first edge section (30) extends along at least one third and in particular along at least half of the virtual connecting line (V'). [14] Separator plate (2) according to one of the preceding claims, wherein second ends (34) of the first webs (24) face the through-opening (11a-c) and are connected to one another by a virtual connecting line (V'), wherein the virtual connecting line (V') and an edge section (30) of the through-opening (11a-c) extend at least over half, preferably over at least 70% of their course at a constant distance from one another. [15] Separator plate (2) according to one of the preceding claims, wherein second ends (34) of the first webs (24) are opposite the through-opening (11a-c), wherein at least some of the distances (B) between the respective second ends (34) of mutually adjacent first webs (24) are homogeneous. [16] Separator plate (2) according to the preceding claim, wherein the second ends (34) of the first webs (24) extend along a width axis (B 17) of the separator plate (2) and the distribution area (20) along the width axis (B 17 ) has a first outermost first web (24') and a second outermost first web (24"), wherein inner first webs (24) are arranged between these two outermost first webs (24'), and wherein for the inner first webs (24) first distances (A, B) between the respective second ends (34) of mutually adjacent first webs (24) are homogeneous. [17] Separator plate (2) according to one of the preceding claims, wherein for at least 80% of the first channels (22) and / or the first webs (24), the first channels (22) and / or the first webs (24) are at least five times and in particular at least ten times as long as they are wide. [18] Separator plate (2) for an electrochemical system (1), comprising: - at least one through-opening (11a-c) for passing a fluid through the separator plate (2), - at least one distribution area (20) having a plurality of first channels (22) and first webs (24) formed between each two first channels (22), - at least one flow field (17) which is in fluid communication with the through-opening (11a-c) via the distribution region (20), wherein second ends (34) of the first webs (24) are opposite the through-opening (11a-c), wherein at least some of the distances (B) between the respective second ends (34) of mutually adjacent first webs (24) are inhomogeneous. [19] Separator plate (2) according to the preceding claim, wherein the second ends (34) of the first webs (24) extend along a width axis (B 17 ) of the separator plate (2) and the distribution area (20) along the width axis (B 17) has a first outermost first web (24') and a second outermost first web (24"), wherein first inner webs (24) are arranged between these two outermost first webs (24', 24"), and wherein for the inner first webs (24) distances (B) between the respective second ends (34) of mutually adjacent first webs (24) are inhomogeneous.

Images