Stacking method and cell layer for an electrochemical cell stack

Abstract

The invention relates to a method for stacking an electrochemical cell stack (10, 60), in particular an electrolysis cell stack (60) or a fuel cell stack (10), wherein unit layers (100, 100, …) for a cell stack (10, 60) growing in the axial direction (Ar) are gripped by a gripper (210), forwarded in the chronological sequence and stacked in the chronological sequence to form the cell stack (10, 60), wherein an individual unit layer (100) comprises two cell layers (110, 120), and a first cell layer (110) is formed as a polar plate (110), in particular a bipolar plate (110), and a second cell layer (120) is formed as a cell frame (120) with an electrochemical single cell (11, 61) oriented therein.

Description

[0001] R. 414452

[0002] - 1 -

[0003] Description

[0004] title

[0005] Stacking method and cell layering for an electrochemical cell stack

[0006] The invention relates to a method for stacking an electrochemical cell stack and to a cell layer for an electrochemical cell stack. Furthermore, the invention relates to an electrochemical cell stack, an electrochemical assembly, and an electrochemical system.

[0007] State of the art

[0008] In an electrolyzer of an electrolyzer unit (stationary or mobile), e.g., an electrolyzer system, water is electrochemically converted into hydrogen and oxygen using electrical energy, generating heat in the process. In a low-temperature polymer electrolyte fuel cell of a fuel cell unit (mobile or stationary), e.g., a fuel cell system in a fuel cell vehicle, two reactants of two operating media are electrochemically converted into electrical energy and heat.

[0009] The assembly in question can comprise at least one membrane electrode assembly, for example, a membrane electrode assembly (MEA) with a proton exchange membrane (PEM) or an anion exchange membrane (AEM). Alternatively to the MEA, at least one electrode of a membrane electrode assembly can be located away from and directly opposite the membrane on at least one fluid transport structure of the membrane electrode assembly. The assembly can be designed with a plurality of membrane electrode assemblies or analogues arranged in a stack and bipolar plates arranged between them, forming an R. 414452

[0010] - 2 - form an electrochemical cell stack with a plurality of individual cells.

[0011] For example, in an electrolysis cell stack, the layers of its individual cells, as well as the individual cells of the entire electrolysis cell stack, must be stacked sequentially at a single workstation. Current electrolysis cell stacks consist of approximately 100 to 200 individual cells, which must be assembled and stacked one after the other. All components must be assembled at a single workstation, and this single step is very time-consuming. For mass production, numerous assembly stations would be required, each with its own equipment. In the event of a malfunction, the entire assembly station would be shut down.

[0012] Task

[0013] There are ongoing efforts to improve electrolyzer and fuel cell systems and to design them to be cost-effective in terms of materials, manufacturing costs, and / or maintenance costs. An object of the invention is to design a stacking method (pre-assembly) for an electrochemical cell stack for such a system in a safe, fast, and therefore cost-effective manner.

[0014] Disclosure of the invention

[0015] The object of the invention is achieved by a method for stacking an electrochemical cell stack, in particular an electrolysis cell stack or a fuel cell stack; by means of a cell layer, in particular a polar plate, a cell frame or a unit layer for an electrochemical cell stack, in particular a fuel cell stack or an electrolysis cell stack; and by means of an electrochemical cell stack, in particular a fuel cell stack or an electrolysis cell stack, an electrochemical assembly, in particular a fuel cell assembly or an electrolyzer assembly, and an electrochemical system, in particular a fuel cell system or an electrolyzer system. - Advantageous R. 414452

[0016] - 3 -

[0017] Further developments, additional features and / or advantages of the invention will become apparent from the dependent claims and the following description.

[0018] In the method according to the invention, unit layers for an axially growing cell stack are successively or (multiple times) simultaneously gripped by a gripper, preferably passed on in immediate succession, and stacked in preferably immediate succession to form the cell stack, wherein a single unit layer comprises two cell layers, and a first cell layer is designed as a polar plate, in particular a bipolar plate, and a second cell layer as a cell frame with an electrochemical single cell arranged therein. The invention implements a single-cell (pre-)assembly (single-cell or cell-unit (pre-)assembly) of an electrochemical cell stack. The unit layers can be, or be, tested for functionality before being stacked.

[0019] The gripper is, of course, primarily an end effector of a robot arm (manipulator) of an industrial robot for handling or assembling workpieces. Depending on the path over which the unit layers must be transferred—that is, moved or transported—the robot base of the industrial robot is designed to be movable. However, a stationary robot base is preferred, whereby the robot arm—apart from its gripping and positioning tasks, such as a potentially necessary 180° rotation of a unit layer—preferably only needs to perform pivoting movements.

[0020] When stacking the unit layers into a cell stack, the robot arm uses its gripper to pick up one or more unit layers from a staging area and pass them to the assembly station. There, the robot arm places at least one unit layer onto the growing cell stack with its releasing gripper until it contains the desired number of individual cells. Once the cell stack is complete, it is removed from the assembly station, and the industrial robot can stack the next cell stack. The staging area is preferably supplied with the unit layers from a pre-assembly station. R. 414452

[0021] - 4 -

[0022] The electrochemical cell of the cell frame preferably comprises a first fluid transport structure, optionally with one electrode, a membrane (e.g., a PEM or AEM), optionally with one or two electrodes (CCM: Catalyst Coated Membrane), and a second, optionally multilayered, fluid transport structure, optionally with one electrode, wherein the electrochemical cell has exactly two electrodes, one each between the respective actual fluid transport structure and the actual membrane. Within the scope of the process, the electrochemical cell naturally only possesses the suitability for its electrochemical function, without yet being electrochemically functional in the intended sense.

[0023] In some embodiments, the arrangement of the electrochemical cell within the cell frame and its orientation relative to the polar plate for the stacking process and in the growing or assembled cell stack can be essentially identical. In the assembled state of the cell stack, an axial clamping force is disregarded, as this force merely clamps the electrochemical cell within the cell frame and the polar plate together. Preferably, these two cell layers are arranged centered or coaxially to each other.

[0024] The two cell layers are arranged axially one above the other as a unit layer and can be loosely connected, semi-rigidly, or rigidly joined. In the first case, the two cell layers can form a stacked composite. The semi-rigid composite is characterized in particular by the fact that the two cell layers are conditionally connected to each other in a force-transmitting manner and, in particular, cannot move relative to each other in a common plane, or only with an intentional force. The rigid composite should be at least strong enough that, in a gravitational field, a lower cell layer cannot detach from its upper cell layer when the unit layer is lifted above its upper cell layer and the lower cell layer is not affected in the process.

[0025] The two cell layers can be secured against mutual slippage in a common plane, at least by means of fluid seals between the two cell layers as a unit layer. - The gripper can be designed as a vacuum gripper, by which at least one unit layer is suctioned in during gripping, and / or as a mechanical gripper, by which, during R. 414452

[0026] - 5 -

[0027] At least one unit layer is gripped at its periphery and subsequently passed on to an assembly station, where it is stacked onto the growing cell stack. This means the gripper can be designed as a combination gripper, comprising both mechanical and vacuum components, or as a mechanical / vacuum gripper.

[0028] In the following, a proximal cell layer is defined as the cell layer that, before and during the stacking process, is closer to or directly adjacent to the actual gripper. A distal cell layer is defined as the cell layer that is further away from or indirectly adjacent to the gripper. During the stacking process, the proximal cell layer of the unit layer is positioned between the distal cell layer and the gripper.

[0029] To handle at least one unit layer with a vacuum gripper during grasping and passing, a distal cell layer can be suctioned through a proximal cell layer, with the distal cell layer pressing the proximal cell layer against the vacuum gripper. Alternatively, a proximal cell layer can be suctioned by a vacuum gripper during grasping and passing, with the distal cell layer being carried along by the proximal cell layer during passing. In the first case, the proximal cell layer can have through-holes to allow suction of the distal cell layer, whereas in the second case, the proximal cell layer has blind holes and the distal cell layer is firmly connected to the proximal cell layer.

[0030] Additionally or alternatively, a mechanical gripper can grasp a distal cell layer during grasping and passing, whereby the proximal cell layer is also picked up by the distal cell layer during passing. Furthermore, a mechanical gripper can grasp both cell layers together during grasping and passing, and both cell layers are passed directly from the mechanical gripper during passing. In these cases, no (additional) fixed connection between the two cell layers of a unit layer is necessary. R. 414452

[0031] - 6 -

[0032] Thus, when gripped by the vacuum gripper, the polar plate can be drawn through the cell frame, thereby bringing the cell frame into mechanical contact with the vacuum gripper. Or, vice versa, when gripped by the vacuum gripper, the cell frame can be drawn through the polar plate, thereby bringing the polar plate into mechanical contact with the vacuum gripper. The unit layer thus gathered during gripping can then be passed on and stacked onto the growing cell stack. When the unit layer is gathered by the vacuum gripper, the layers of the electrochemical individual cells contained within it are preferably clamped together directly using mechanical force. Additionally or alternatively, the unit layer can be drawn in, particularly via the cell frame, as a proximal cell layer, whereby such a suction action does not at least partially gather the unit layer together.

[0033] Furthermore, when the mechanical gripper grasps the polar plate, the cell frame resting on it in the gravitational field can be moved along with it. Or, vice versa, when the mechanical gripper grasps the cell frame, the polar plate resting on it in the gravitational field can be moved along with it. Additionally, when the mechanical gripper grasps the polar plate and the cell frame together in any desired arrangement within the gravitational field. Such a grasped unit layer can then be passed on and stacked onto the growing cell stack.

[0034] Furthermore, to handle at least one unit layer using a mechanical gripper, a proximal cell layer can be mechanically gripped during grasping and passing, whereby the distal cell layer is also picked up during passing. In this case, an (additional) firm connection between the two cell layers is necessary, such as a latch, a locking mechanism, a clip, a mutual (e.g., external and possibly removable) support, mutual adhesion via seals or adhesive bonding, etc.

[0035] When gripping and passing by the mechanical gripper, the cell frame can be gripped or be gripped, whereby the components firmly connected to the cell frame are R. 414452

[0036] - 7 - the lower polar plate in the gravitational field moves along with it when passed on. Or, vice versa, when grasping and passing by the mechanical gripper, the polar plate can be grasped or already grasped, whereby the lower cell frame, which is firmly connected to the polar plate and moves along with it in the gravitational field, during the passing on. - Such a unit layer can then be stacked onto the cell stack that is thereby growing.

[0037] The proximal cell layer, in particular the cell frame or the polar plate, can have suction holes through which the distal cell layer, in particular the polar plate or the cell frame, can be suctioned, wherein for gripping the vacuum gripper is placed on the proximal cell layer from the large surface area and the vacuum gripper suctions the distal cell layer through the suction holes and thus grips the unit layer.

[0038] During the stacking process, the vacuum gripper can suction the unit layer through: peripheral suction holes in the proximal cell layer, suction holes in the corner areas of the proximal cell layer, suction holes radially outside a sealing surface for a peripheral seal on or a peripheral seal of the proximal cell layer, fluid-sealed suction holes in the proximal cell layer relative to the distal cell layer, a plurality of suction holes with a diameter in the centimeter range in the proximal cell layer, a perforation with a plurality of suction holes with a diameter in the millimeter range in the proximal cell layer, and / or through suction holes arranged at least once, twice, three times, four times, or multiple times in a mirror-symmetrical manner in the proximal cell layer.

[0039] At least the proximal cell layer, in particular the cell frame or the polar plate, can have peripheral grasping access points by means of which the distal cell layer, in particular the polar plate or the cell frame, can be mechanically grasped, wherein for grasping the mechanical gripper is applied to the distal cell layer from the periphery and the mechanical gripper grasps the distal cell layer peripherally via the grasping access points and thus the unit layer is grasped peripherally. R. 414452

[0040] - 8 -

[0041] During the stacking process, the mechanical gripper can grip the unit layer in the following ways: into gripping accesses in an outer circumferential edge in the radial outer section of the cell layer, into gripping accesses in the corner areas of the unit layer, into gripping accesses as material recesses (cell frames) and / or wall steps (polar plate) in the unit layer, and / or into gripping accesses arranged at least or exactly: simply, twice, three times, four times or multiple times in a mirror-symmetrical manner in the unit layer.

[0042] The gripper can have an inner contour on the side, e.g., the large-area side, from which it grips the unit layer, which is essentially complementary to the outer contour of the unit layer. Furthermore, for releasing the unit layer by the vacuum gripper, it can be advantageous if an internal structure, in particular a mesh (see below), of the electrochemical cell in the unit layer to be stacked extends beyond the free side of the proximal cell frame, thereby providing a spring force that pushes the unit layer away from the gripper in a perpendicular direction when released.

[0043] For suction of the unit layer, the suction nozzles of the vacuum gripper can penetrate suction holes in the unit layer. A suction nozzle that has penetrated a suction hole can be configured with a fluid-throttling annular gap in the suction hole. The cell frame can be configured as a cell layer according to the invention (see below) and / or the unit layer can be configured as a cell layer according to the invention (see also below). Pre-assembled unit layers can be provided for the stacking process. Alternatively, the stacking process can include a pre-assembly process by which polar plates, cell frames, and electrochemical individual cells are pre-assembled into unit layers.

[0044] The stacking method can include a pre-assembly process, wherein in a first step a cell frame is positioned on a polar plate, and in a second step following the first step a first fluid transport structure is placed within the cell frame on the polar plate. Preferably, this fluid transport structure is designed as a gas diffusion layer (GDL). In a third step following the second step, a membrane is placed on the first R. 414452

[0045] - 9 -

[0046] Fluid transport structure and preferably placed on a radial inner rim of the cell frame.

[0047] In a fourth step following the third, a second, possibly multi-layered, fluid transport structure is placed on the membrane. This fluid transport structure is preferably designed as a porous transport layer (PTL), which may have multiple layers, for example, an inner layer of sintered titanium and two different meshes (metal meshes, metal braids, etc.). The second fluid transport structure can be used as a pre-assembled fluid transport structure, or its layers can be successively built up on the membrane in the fourth step. Furthermore, the pre-assembly process is preferably designed such that no rotation, in particular no 180° rotation, of the resulting unit layer is necessary. The pre-assembly process may, of course, include intermediate steps.

[0048] The cell layer according to the invention has a radial outer section that completely surrounds the cell layer in the circumferential direction, within which an electrochemical single cell can be assembled (polar plate) or received (cell frame) for the cell stack, wherein a stacking device with a plurality of stacking devices is arranged on / in the radial outer section, by means of which the cell layer can be grasped, transferred and / or stacked by a gripper, in particular a vacuum gripper and / or a mechanical gripper. The assembly of the electrochemical single cell on the cell layer (polar plate) is carried out in particular with the aid of a second cell layer (cell frame), thereby obtaining a unit layer (pre-assembly method).

[0049] The stacking devices of the stacking unit can be configured as suction holes for a vacuum gripper, wherein the suction holes are arranged radially outside a sealing surface for a peripheral seal or radially outside a peripheral seal in the radial outer section of the cell layer. Additionally or alternatively, the stacking devices of the stacking unit can be configured as gripping access points for a mechanical gripper, wherein the gripping access points are arranged as material recesses or wall steps in an outer circumferential edge in the radial outer section of the cell layer. R. 414452

[0050] - 10 -

[0051] The gripping access points are specifically positioned within the cell layer to provide space for the fingers of the mechanical gripper to grasp an adjacent cell layer (polar plate or cell frame) within the same unit layer, where the unit layer comprises a cell frame and a polar plate (see Fig. 4). Furthermore, gripping access points axially opposite these provide space for the fingers of the mechanical gripper to place a unit layer onto an already placed unit layer (see Fig. 5).

[0052] The gripping access points in a cell frame are preferably designed as material recesses in the cell frame, which are accessible to the mechanical gripper from the radial outside. The alternative or, if necessary, additional gripping access points in a polar plate are preferably designed as wall steps in the polar plate, which are also accessible to the mechanical gripper from the radial outside. Depending on the size of a particular finger of the mechanical gripper, material recesses in the cell frame and wall steps in the polar plate can, of course, be axially opposed to each other, thus providing more space for a particular finger of the mechanical gripper; this applies to a single unit layer or to two unit layers stacked on top of each other.

[0053] In various embodiments, suction holes can be: located at the periphery and / or corners of the cell layer; configured as through holes and / or blind holes in the cell layer; have a diameter in the centimeter range and / or the millimeter range (perforation); and / or be arranged at least or exactly: simply, twice, three times, four times, or multiple times in a mirror-symmetrical manner within the cell layer. Furthermore, in various embodiments, gripping access points can be: located in an outer circumferential edge in the radial outer section and / or in the corners of the cell layer; be designed as material recesses and / or wall steps in the cell layer; and / or be arranged at least or exactly: simply, twice, three times, four times, or multiple times in a mirror-symmetrical manner within the cell layer.

[0054] The cell frame and / or polar plate can, of course, have an essentially rectangular, square, elliptical, circular, etc. plan. A different plan of the cell frame or polar plate, such as that of R. 414452, is also possible.

[0055] - 11 -

[0056] Polygons, especially regular polygons, are of course applicable. - The cell frame can be integral, made of a single piece, in one part, in two parts, or in multiple parts. Furthermore, the bipolar plate can be made of a single piece, in particular from two integral monopolar plates, in two parts, in one part, or in one piece.

[0057] A one-piece design refers to a component (cell frame or bipolar plate) in which its components are bonded together by force and / or form fit, and the component can preferably be separated into its components again without damage, possibly with the use of a tool. A one-piece (adhesive) design, on the other hand, refers to a component in which its individual parts are bonded together by material (gluing, laminating, soldering, welding, etc.), and the component preferably cannot be separated into its individual parts without damaging one of its components. The cohesion of the component can further be achieved by force and / or form fit (not in the case of integral designs).

[0058] An integral design refers to a component (e.g., a cell frame as a combination frame or monopolar plate) in which there is only a single component that can only be divided by destroying it. The component is manufactured from a single original piece and / or a single original material (molten plastic or molten metal), which is itself necessarily integral. Internal cohesion is achieved (exclusively) by adhesion and / or cohesion. In certain embodiments, the cell frame and / or a monopolar or bipolar plate may additionally feature a coating, integral deposition, lamination, etc.

[0059] The cell layer can be configured as a unit layer with at least or exactly two cell layers, wherein a first cell layer is configured as a polar plate, in particular a bipolar plate, and a second cell layer is configured as a cell frame with an electrochemical single cell installed therein. The polar plate and / or the cell frame of the unit layer can include a stacking device of the unit layer, with a plurality of stacking devices. R. 414452

[0060] - 12 -

[0061] In some embodiments, the electrochemical cell on the polar plate can comprise a membrane between two fluid transport structures. The membrane can be positioned on a radial inner rim (terrace) of the cell frame. A seal can be provided between the radial inner rim and the membrane, for which the terrace may have a recess or groove. Alternatively, the seal can also be formed, provided, and / or integrated into the membrane.

[0062] In some embodiments, suction holes in the relevant (i.e., the proximal) cell layer can be fluid-sealed relative to the other (i.e., the distal) cell layer within the unit layer. A corresponding gripping access point can be realized in only one cell layer or as a combined gripping access point through both cell layers. That is, the gripping access points of a single unit layer can be partially or completely realized through the polar plate, the cell frame, and / or both the polar plate and the cell frame. The cell layer can be stackable and / or stacked as a unit layer using a stacking method according to the invention.

[0063] The cell stack, the aggregate, and the system according to the invention each comprise a plurality of cell layers, wherein the cell stack, or a cell stack of the aggregate or the system, is constructed by a stacking method according to the invention, and / or cell layers of the cell stack, the aggregate, or the system are designed according to the invention. The cell stack preferably comprises end plates and / or a clamping element. Furthermore, the aggregate and / or the system particularly comprises a control unit for controlling and / or regulating the operation of its at least one cell stack.

[0064] Brief description of the characters

[0065] The invention is explained in more detail below with reference to exemplary embodiments and the accompanying schematic drawing, which is not to scale. In the invention, a feature can be positive (i.e., present) or negative (i.e., absent). In this specification, a negative feature is not explicitly defined as a feature unless otherwise specified in Inventory R. 414452.

[0066] - 13 - The emphasis is placed on its absence. That is, the actual invention, and not one constructed by the prior art, consists in omitting this feature. The absence of a feature (negative feature) in an embodiment shows that the feature is optional (to a person skilled in the art). - The merely exemplary and schematic figures (Fig.) of the drawing show:

[0067] Fig. 1 shows a simplified block diagram of an embodiment of a fuel cell unit with an electrochemical fuel cell stack for a fuel cell system of a fuel cell vehicle; Fig. 2 shows a simplified block diagram of an embodiment of an electrolyzer unit with an electrochemical electrolysis cell stack for an electrolyzer system, e.g., an electrolyzer plant; Fig. 3 shows a highly schematic view of an assembly station of an industrial robot with its robot arm in two positions during the stacking of unit layers to form an electrochemical cell stack; Fig. 4 shows a flowchart of a method according to the invention for stacking an electrolysis cell stack or a fuel cell stack for a fuel cell unit or an electrolyzer unit; Fig. 5 shows a section cut away laterally through a structure that differs from the figures shown.Figures 3 to 5 show a unit layer in more detail within the context of handling the unit layer by a vacuum gripper, Figure 6 shows a perspective view of a cell layer designed as a cell frame for a unit layer according to the invention of an electrochemical electrolysis cell stack, and Figures 7 to 9 show, in each case highly schematic, a laterally broken-off section through a unit layer for such a cell stack within the context of handling the unit layer by a gripper.

[0068] Embodiments of the invention

[0069] The invention relates to a stacking method 400 or an assembly method 400 for stacking a cell stack 10, 60 (see Figs. 8 and 9) and to an electrochemical unit layer 100 for the cell stack 10, 60 (before and during the stacking method 400) or the cell stack 10, 60 (according to R. 414452).

[0070] - 14 - the stacking method 400), as cell layer 100 with a first cell layer 110 and a second cell layer 120 is explained in more detail (see Figs. 3 to 7). Here, the unit 1, 51 can be designed as a fuel cell unit 1 (see Fig. 1) for a mobile or stationary fuel cell system, or also as a stationary or mobile electrolyzer unit 51 (see Fig. 2) for an electrolyzer system.

[0071] The drawing shows only those sections of the fuel cell system or electrolyzer system that are necessary for understanding the invention. Although the invention is described and illustrated in detail by preferred embodiments, the invention is not limited by the disclosed embodiments. Other variations can be derived from them without departing from the scope of protection of the invention.

[0072] Figures 1 and 2 each show an electrochemical unit 1, 51 (Fig. 1: fuel cell unit 1, Fig. 2: electrolyzer unit 51) according to a general embodiment, with at least one, in particular a plurality of, electrochemical individual cells 11, 61 (Fig. 1: individual fuel cells 11, Fig. 2: individual electrolysis cells 61) bundled to form an electrochemical cell stack 10, 60 or a stack 10, 60 (Fig. 1: fuel cell stack 10, Fig. 2: electrolysis cell stack 60), which are housed in a preferably fluid-tight stack housing 16, 66.

[0073] Each individual cell 11, 61 comprises an electrode compartment 12, 62 configured as an anode compartment 12, 62 and an electrode compartment 13, 63 configured as a cathode compartment 13, 63, which are spatially and electrically separated from each other by a membrane 150 or a membrane 150 of an MEA or a CCM. An electrically conductive fluid transport structure 140 is provided in each electrode compartment 12, 13; 62, 63, which is in fluid communication with a polar plate 110. Alternatively, or in addition to an MEA or a CCM with only one electrode, at least one electrode can also be provided away from the membrane 150 on at least one fluid transport structure 140.

[0074] A membrane electrode assembly 15, 65 of the cell stack 10, 60 has a membrane 150 or a membrane 150 of an MEA or a CCM, as well as at de- R. 414452

[0075] - 15 - large-area fluid transport structures 140 are shown. A single fluid transport structure 140 can comprise a transport layer, a transport layer, a PTL (Porous Transport Layer), a GDL (Gas Diffusion Layer), a sintered metal element, a sintered metal paper, a fiber element, a carbon layer, a carbon paper, a flow structure, and / or a flow field, etc. The fluid transport structures 140 not explicitly shown in Figures 1 and 2 are arranged in the anode spaces 12, 62 and the cathode spaces 13, 63 of the cell stack 10, 60.

[0076] A bipolar plate 110 is arranged between two directly adjacent membrane electrode arrangements 15, 15; 65, 65 including a respective anode compartment 12, 62 and a corresponding cathode compartment 13, 63, which serves, among other things, to supply / discharge media 3 / 4, 5 / 6, 7 / 8; 53 / 54, 56 to an anode compartment 12, 62 of a first single cell 11, 61 or a cathode compartment 13, 63 of a directly adjacent second single cell 11, 61 and also provides an electrically conductive connection between these single cells 11, 11; 61, 61. - The cathode spaces 13, 63 and, if applicable, their common inflow area or their actual electrodes form a cathode 39, 89, and the anode spaces 12, 62 and, if applicable, their common inflow area or their actual electrodes form an anode 29, 79 of the cell stack 10, 60.

[0077] In principle, the membranes of the cell stack can comprise 10 or 60 PEMs (proton exchange membranes) or AEMs (anion exchange membranes). Preferably, a fuel cell stack comprises 10 PEMs and an electrolysis cell stack comprises 60 AEMs or PEMs. The fuel cell system or electrolyzer system comprises, in addition to the fuel cell unit 1 or the electrolyzer unit 51, peripheral system components, such as a control unit, which can be one of the fuel cell system or the electrolyzer system itself, etc.

[0078] The following explanations relate solely to the electrochemical unit 1 as fuel cell unit 1, e.g., according to Fig. 1. - For supplying the electrochemical cell stack 10 as fuel cell stack 10 with its actual operating media 3 (anode operating medium 3, actual fuel R. 414452).

[0079] - 16 -

[0080] 3), 5 (cathode operating medium 5 , mostly air 5) the fuel cell unit 1 has an anode supply 20 and a cathode supply 30.

[0081] The anode supply 20 preferably comprises: a fuel storage 23 for the anode operating medium 3 (flowing in); an anode supply path 21 (medium path 21) with a pressure reducer, a shut-off valve and / or a metering valve 27 (by way of example), as well as a jet pump 24 (jet pump 24, e-ejector 24); an anode exhaust path 22 (medium path 22) for an anode exhaust medium 4 (flowing out, usually into the environment 2); a fuel recirculation path 25 with a fluid conveying device 26 located therein; optionally a water separator with preferably a water tank.

[0082] The cathode supply 30 preferably comprises: a cathode supply path 31 (medium path 31) for the cathode operating medium 5 (flowing in, usually from the environment 2), with a fluid conveying device 33; a cathode exhaust path 32 (medium path 32) for a cathode exhaust medium 6 (flowing out, usually into the environment 2), with preferably a turbine 34, in particular for the fluid conveying device 33; a moisture exchanger 36, in particular a gas-to-gas humidifier 36; optionally a cathode-side stack bypass 35 (wastegate 35) between the cathode supply path 31 and the cathode exhaust path 32, with a bypass valve 37; optionally a water separator with preferably a water tank.

[0083] The fuel cell assembly 1 further comprises, in particular, a cooling medium supply 40 of a thermal system, through which the fuel cell stack 10 can preferably be integrated into a cooling circuit for temperature control by means of its polar plates 110 (cooling medium paths 43). The cooling medium supply 40 comprises a cooling medium inlet path 41 and a cooling medium outlet path 42. The cooling medium 7 (inflow), 8 (outflow) circulating in the cooling medium supply 40 is preferably conveyed by means of at least one cooling medium conveying device 44.

[0084] The following explanations relate solely to the electrochemical unit 51 as electrolyzer unit 51, e.g., according to Fig. 2. - For supplying the electrochemical cell stack 60 as electrolysis cell stack 60 with, e.g., if necessary, R. 414452.

[0085] - 17 - mildly alkaline water 53 as a supply medium 53, the electrolyzer unit 51 has a medium supply 70. And for taking the media 54, 56 from the cell stack 60, the electrolyzer unit 51 has a medium withdrawal 80.

[0086] The medium supply 70 preferably comprises: a medium reservoir 73 for the supply medium 53 (flowing in), a supply path 71 (medium path 71) and a conveying device 76 on / in the supply path 71. - The medium extraction 80 has at least one disposal path 81 (medium path 81) for a disposal medium 54 or a disposal medium 54 with oxygen back into the medium reservoir 73, optionally with a gas separator for oxygen, and / or in another direction (shown with dashed lines), e.g. into the environment 2.

[0087] A product medium 56 from the electrolyzer unit 51, i.e., the produced hydrogen 56, is transported through a product medium path 82 from the media outlet 80. A gas / liquid separator 83 with a valve 84 can be installed in the product medium path 82 to separate waste medium 54 from the product medium path 82. The waste medium 54 separated in the gas / liquid separator 83 can be conveyed back into the medium reservoir 73 or in another direction, e.g., to the environment 2, possibly by gravity. The produced hydrogen 56 can, for example, be stored in a hydrogen storage tank 90, with the product medium path 82 potentially leading directly into the hydrogen storage tank 90. ​​Other methods of transporting the hydrogen 56 are, of course, possible.

[0088] Depending on the embodiment of the electrolyzer unit 51, the media flow within the cell stack 60 can be configured differently. It is possible to provide a temperature control system that differs from the electrochemical function of the cell stack 60, in particular water cooling, or to implement the temperature control system together with the electrochemical function of the cell stack 60.

[0089] In membrane electrode devices 65 with AEMs, it is possible to have, in addition to an anode- and cathode-side, a possibly exclusively anode-side (dotted- R. 414452)

[0090] - 18 - third arrow at the anode 79) Supply of the supply medium 53, possibly also as a cooling medium. Furthermore, in membrane electrode devices 65 with PEMs, it is possible to set up, in addition to an exclusively anode-side supply, an optionally exclusively cathode-side 89 supply of the supply medium 53, possibly also as a cooling medium (dotted arrow at the cathode 89).

[0091] An embodiment of the stacking method 400 of the cell stack 10, 60 according to the invention is explained in more detail below with reference to Figures 3 and 4. Figure 3 shows a workstation of an industrial robot with a staging station on the left and an assembly station on the right, of which only one robot arm 200 with its gripper 210 is shown in two positions, the gripper 210 being designed as a vacuum gripper 210 and / or a mechanical gripper 210. Figure 4 shows a flowchart of the stacking method 400 to be carried out by the industrial robot with the repeating steps: gripping 410, passing 420 and stacking 430, each of at least one unit layer 100 for and onto the growing cell stack (10), (60).

[0092] The unit layer 100 is the smallest unit of the cell stack 10, 60, which is repeated within the cell stack 10, 60 and with which the essential inner or actual cell stack 10, 60 – i.e., the cell stack 10, 60 apart from its end plates, its screw connections, its terminals, etc. – is constructed. A structure of the essentially two-layer unit layer 100 is explained in more detail below, particularly with reference to Fig. 5, wherein the at least two layers 110, 120 of the unit layer 100 naturally have a substructure also in the form of layers.

[0093] The stacking process 400 can be preceded by a pre-assembly process 300 (see above and the explanations for Fig. 5) (supplying the staging area). Alternatively, the pre-assembly process 300 can be part of the stacking process 400 (loading the staging area). - In the pre-assembly process 300, the unit layers 100 are pre-assembled. In the first case, the pre-assembly process 300 can already be completed before the stacking process 400 begins. In the second case, the pre-assembly process 300 can also run in parallel with the stacking process 400. - In the pre-assembly process 300, the R. 414452

[0094] - 19 -

[0095] Unit layers 100 pre-assembled, which are stacked later or essentially directly following the actual cell stack 10, 60.

[0096] In the first step 410 of the stacking process 400, the gripper 210 grasps the unit layer 100 in the staging area. In the second step 420, the gripper 210 passes the unit layer 100 to / into the assembly station. In the third step 430, the gripper 210 stacks the unit layer 100 onto the cell stack 10, 60 that is thereby growing in the assembly station. For grasping 410, passing 420, and stacking 430 of a unit layer 100, the gripper 210 engages one or both of its cell layers 110 / 120 (see below). In each stacking cycle, the gripper 210 can grasp 410, pass 420, and stack 430 a single unit layer 100 or multiple unit layers 100.

[0097] Fig. 5 shows a unit layer 100 for the cell stack 10, 60, arranged in the axial direction Ar, comprising a cell layer 110, which is configured as a polar plate 110, e.g., a monopolar plate 110 or, in particular, as a bipolar plate 110, and a cell layer 120, which is configured as a cell frame 120. The cell layer 110, or polar plate 110, can be configured as a gripper-distal or gripper-proximal cell layer 110 or polar plate 110 for the stacking process, and the cell layer 120, or cell frame 120, can be configured as a gripper-proximal or gripper-distal cell layer 120 or cell frame 120 for the stacking process.

[0098] Furthermore, the cell layers 110, 120, see also Fig. 6, extend with their surfaces in the radial direction Rr and circumferential direction Ur of the unit layer 100. The axial direction Ar, the radial direction Rr and the circumferential direction Ur are naturally also those of the cell stack 10, 60. Such a unit layer 100 is assembled in a pre-assembly process 300, wherein the pre-assembly process 300 preferably comprises the following steps: positioning a cell frame 120 on a polar plate 110, in particular a bipolar plate 110; placing a first fluid transport structure 140, 144 / 142 within the cell frame 120 on the polar plate 110; Placing a membrane 150 on the first fluid transport structure 140, 144 / 142 and placing a second fluid transport structure 140, 142 / 144 on the membrane 150 within the cell frame 120. R. 414452

[0099] - 20 -

[0100] Within the assembly of the two fluid transport structures 140; 144, 142 with the intervening membrane 150, two electrodes 29, 39; 79, 89 are provided, wherein one electrode 29 / 39; 79 / 89 is formed integrally and / or in one piece on the membrane 150 or the fluid transport structure 140, 144 / 142, and the other electrode 39 / 29; 89 / 79 is formed integrally on the membrane 150 or the fluid transport structure 140, 142 / 144, in particular by being deposited as a single piece. The smaller fluid transport structure 140, 144 / 142 is preferably designed as a GDL and the larger fluid transport structure 140, 142 / 144 is preferably designed as a PTL, wherein the PTL may be multilayered.

[0101] The preferably integral, and optionally multi-part, cell frame 120 on the polar plate 110 is preferably formed completely circumferentially Ur, wherein the substantially planar extending membrane 150 is positioned substantially centrally in an inner (frame) opening of the cell frame 120 in the axial direction Ar. The cell frame 120, acting alone, serves as a radial fluid density guide for an electrochemically active region of the respective individual cell 11, 61 in the subsequent cell stack 10, 60.

[0102] Furthermore, the cell frame 120 serves, in particular by means of a radially arranged inner flange 122 or terrace 122, to hold or tension the membrane 150 within the cell frame 120, e.g., by means of the fluid transport structure 140, 142 / 144, whereby or by which the membrane 150 is held or fixed to / in the cell frame 120. An axial inner surface (terrace surface) of the inner flange 122 lies approximately at half the axial height of a radial outer section 126 of the cell frame 120. This inner surface of the inner flange 122 projects radially inwards into the cell frame 120. When the membrane 150 is mounted in the cell frame 120, the cell frame 120 surrounds the membrane 150.

[0103] In the cell frame 120, the membrane 150 can be installed fluid-tight with respect to the radial inner flange 122, or at least later installed in the operational cell stack 10, 60. Of course, the membrane 150 can already be installed fluid-tight in the unit position 100 at the radial inner flange 122. For this purpose, a terrace seal 123 can be installed between the membrane 150 and the radial inner flange 122, the terrace seal 123 being, for example, in a groove or a radial inner flange (dashed line in Fig. 5) of the radial flange.

[0104] - 21 -

[0105] The inner rim 122 can be configured. Alternatively, an analogous seal can be provided on the membrane 150 or formed by the membrane, wherein in the second case the membrane 150 is preferably configured in a groove in the radial inner rim 122. A subsequent sealing force preferably originates from the fluid transport structure 140; 142 / 144, which is configured on the membrane 150 and the radial inner rim 122 in the cell frame 120.

[0106] In one embodiment, the cell frame 120 has a radial outer section 126, preferably substantially rectangular in cross-section (Rr-Ar), which defines an axial height of the cell frame 100. The radial inner flange 122 is connected to this section radially inwards and preferably integrally. The radial outer section 126 of the cell frame 120 preferably has a sealing groove (dashed line in Fig. 5) extending from each of its two axial outer surfaces (Ar) around the entire circumference of the cell frame 100. A peripheral seal 135 is provided in the respective sealing groove, preferably extending radially around all medium passage openings in the cell frame 120.

[0107] Analogous to the radial outer section 126 of the cell frame 120, the polar plate 110 has a radial outer section 116, wherein in the unit position 100 the radial outer sections 116, 126 of the polar plate 110 and the cell frame 120 are arranged axially Ar essentially one above the other; see Figs. 5 and 7 to 9, whereby no medium passage recesses, medium channels or seals are shown in Figs. 7 to 9. In particular, Fig.

[0108] Figures 7 to 9 serve to explain embodiments of the stacking method 400 according to the invention using the gripper 210.

[0109] At least one cell layer 110, 120; 100, i.e., the polar plate 110, the cell frame 120, or the unit layer 100 consisting of the polar plate 110 and the cell frame 120, has a stacking device by means of which the cell layer 110, 120; 100 can be gripped 410, passed 420, and stacked 430 by a gripper 210, in particular a vacuum gripper 210 and / or a mechanical gripper 210, in particular of a robot arm 200 of an industrial robot (stacking method 400). For this purpose, the stacking device has in particular a plurality (i.e., possibly also a multitude) of stacking devices 131, 132, which in particular R. 414452

[0110] - 22 - which may be designed as suction holes 131 for the vacuum gripper 210 and / or gripping access points 132 for the mechanical gripper 210.

[0111] First, let us consider – see Figures 5, 6, 7, and 9 – a single stacking device 131 as a suction hole 131. This single stacking device 131, acting as a suction hole 131, is located in a cell layer 120 / 110 proximal to the vacuum gripper 210. The suction hole 131 can be configured as a through hole 131 or a blind hole 131 (not shown). In principle, such a suction hole 131 can have any cross-section, with a circular, elliptical, rectangular, square, or polygonal cross-section – i.e., a regular cross-section – being preferred.

[0112] A suction hole 131, acting as a through-hole 131, serves to suction the distal cell layer 110 / 120 through the proximal cell layer 120 / 110 using the vacuum gripper 210, thereby drawing the assembly of the proximal cell layer 120 / 110 and the distal cell layer 110 / 120 to the vacuum gripper 210 and simultaneously suctioning the unit layer 100 together. A suction hole 131, acting as a blind hole 131, serves to suction the proximal cell layer 120 / 110 using the vacuum gripper 210 and to pick up the distal cell layer 110 / 120, which is firmly connected to the proximal cell layer 120 / 110.

[0113] That is, the vacuum gripper 210, in the staging area, picks up the unit layer 100 via the stacking device with its stacking devices 131, 131, ... or the suction holes 131, 131, ... in the proximal cell layer 120 / 110 during gripping 410 and thus takes up the entire unit layer 100. Subsequently, the vacuum gripper 210 passes the unit layer 100, thus picked up, to the assembly station 420 and stacks the unit layer 100, thus picked up, onto the cell stack 10, 60 that is thereby growing or being created 430 in the assembly station. Subsequently, the vacuum gripper 210 releases the unit layer 100 and returns to the staging area, where at least one more unit layer 100 is picked up.

[0114] To improve the suction of the unit layer 100, the vacuum gripper 210 can have a suction nozzle 231 (see Fig. 5). Such a suction nozzle 231 can penetrate the suction hole 131 and improve the suction of the unit layer 100. R. 414452

[0115] - 23 - improve. Preferably, the suction nozzle 231 has an outer cross-section congruent with the inner cross-section of the suction hole 131, wherein the outer contour of the suction nozzle 231 can penetrate the inner contour of the suction hole 131 with a small, in particular fluid-throttling, air gap. Naturally, the vacuum gripper 210 can have a plurality of such suction nozzles 231.

[0116] Furthermore, the suction of the unit layer 100 can be improved by means of a suction hole 131, acting as a through-hole 131 in the proximal cell layer 120 / 110, sealed internally within the unit layer 100 with a suction hole seal 136, thus preventing leakage air from being drawn in through the distal end of the through-hole 131. Naturally, multiple such suction hole seals 136 can be incorporated into the unit layer 100. The additional installation of suction hole seals 136 incurs virtually no further costs, as these can be applied together with the other seals of the unit layer 100, particularly those of the cell frame 120.

[0117] And now – see Figures 8 and 9 – to a single stacking device 132 as a gripping access point 132. A single stacking device 132 as a gripping access point 132 is arranged in a cell layer 120 / 110 proximal and / or distal cell layer 110 / 120 relative to the mechanical gripper 210, wherein the gripping access point 132 is preferably designed as a peripheral gripping access point 132 and, in particular, as a material recess 132 and / or a wall step 132 (not shown). Such a gripping access point 132 can, in principle, have any cross-section, with a semicircular, semi-elliptical, rectangular, square, or polygonal cross-section being preferred.

[0118] A gripping access point 132, specifically a material recess 132 in the cell frame 120, serves to provide the mechanical gripper 210 with access, particularly to the polar plate 110. The cell frame 120 can function as a proximal / distal cell frame 120, and the polar plate 110 as a distal / proximal polar plate 110. It is also possible, of course, to grip the cell frame 120 using the mechanical gripper 2 via gripping access points 132 in the cell frame 120. R. 414452

[0119] - 24 -

[0120] A gripping access point 132, specifically in the polar plate 110, serves to provide the mechanical gripper 210 with access, particularly to the cell frame 120. The polar plate 110 can function as a proximal / distal polar plate 110, and the cell frame 120 as a distal / proximal cell frame 120. Of course, it is also possible to grip the polar plate 110 using the mechanical gripper 2 via gripping access points 132 of the polar plate 110.

[0121] It is of course possible to form a single gripping access point 132 from a material recess 132, particularly in the cell frame 120, and a wall step 132, particularly in the polar plate 110 (corresponding partial gripping access points). Such partial gripping access points consisting of a material recess 132 and a wall step 132 are, of course, arranged one above the other in the axial direction Ar in the unit position 100, wherein the two opposing base surfaces of the partial gripping access points preferably have essentially the same shape. - This is not shown in the drawing.

[0122] For stacking the cell stack 10, 60, the mechanical gripper 210 in the staging area grasps the unit layer 100 via the stacking device with its stacking devices 132, 132, ... or the gripping access points 132, 132, .... The mechanical gripper 210 can grasp either the distal cell layer 110 / 120 or the proximal cell layer 120 / 110, whereby in the latter case the distal cell layer 110 / 120 must be firmly connected to the proximal cell layer 120 / 110. Alternatively, the mechanical gripper 210 can grasp both cell layers 110, 120, i.e., the entire unit layer 100.

[0123] Subsequently, the mechanical gripper 210 passes the gripped unit layer 100 to the assembly station 420 and stacks the gripped unit layer 100 onto the resulting cell stack 10, 60 at the assembly station 430. Subsequently, the vacuum gripper 210 releases the unit layer 100 and returns to the staging station where at least one more unit layer 100 is gripped.

Claims

R. 414452 - 25 - Claims 1. Method (400) for stacking an electrochemical cell stack (10, 60), in particular an electrolysis cell stack (60) or a fuel cell stack (10), characterized in that Unit layers (100, 100, ...) for an axially growing cell stack (10, 60) are gripped (410) by a gripper (210), passed on in a temporal sequence (420) and stacked (430) in a temporal sequence to form the cell stack (10, 60), wherein a single unit layer (100) comprises two cell layers (110, 120), and a first cell layer (110) is designed as a polar plate (110), in particular a bipolar plate (110), and a second cell layer (120) is designed as a cell frame (120) with an electrochemical single cell (11, 61) arranged therein.

2. Stacking method (400) according to the preceding claim, characterized in that: • a device of the electrochemical single cell (11, 61) in the cell frame (120) and its orientation to the polar plate (110) for the stacking process (400) and in the cell stack (10, 60) are essentially identical, • the two cell layers (110, 120) are placed one on top of the other as a unit layer (100) in the axial direction (Ar) and are loosely connected to each other, or are semi-solidly or solidly connected to each other, and / or • the two cell layers (110, 120) are secured against mutual slippage in a common plane at least by means of fluid seals between the two cell layers (110, 120) as a unit layer (100).

3. Stacking method (400) according to one of the preceding claims, characterized in that the gripper (210) is designed as a vacuum gripper (210) by which, during gripping, R. 414452 - 26 - at least one unit layer (100) is suctioned, and / or is designed as a mechanical gripper (210) by which at least one unit layer (100) is gripped at its periphery (410) during gripping, and is passed on to an assembly station (420) in a subsequent time and stacked there on the growing cell stack (10, 60) (430).

4. Stacking method (400) according to one of the preceding claims, characterized in that for handling at least one unit layer (100): • by means of a vacuum gripper (210) during gripping (410) and passing (420), a distal cell layer (110 / 120) is suctioned through a proximal cell layer (120 / 110), whereby the distal cell layer (110 / 120) presses the proximal cell layer (120 / 110) against the vacuum gripper (210), and / or • by means of a vacuum gripper (210) during gripping (410) and during passing (420), a proximal cell layer (120 / 110) is suctioned, whereby during passing (420) the distal cell layer (120 / 110) is taken along by the proximal cell layer (110 / 120).

5. Stacking method (400) according to one of the preceding claims, characterized in that for handling at least one unit layer (100): • by means of a mechanical gripper (210) during grasping (410) and passing on (420), a distal cell layer (110 / 120) is mechanically grasped or is grasped, whereby during passing on (420) the proximal cell layer (120 / 110) is taken along by the distal cell layer (110 / 120), • by a mechanical gripper (210) during gripping (410) and passing on (420), both cell layers (110 / 120) are mechanically gripped together, and during passing on (420) both cell layers (110 / 120) are passed on directly by the mechanical gripper (210), and / or • by a mechanical gripper (210) during grasping (410) and passing (420), a proximal cell layer (110 / 120) is mechanically grasped- R. 414452 - 27 - is grasped or has been grasped, whereby when passing (420) through the proximal cell layer (110 / 120) the distal cell layer (120 / 110) is taken along.

6. Stacking method (400) according to one of the preceding claims, characterized in that the proximal cell layer (120 / 110), in particular the cell frame (120), has suction holes (131) through which the distal cell layer (110 / 120), in particular the polar plate (120), can be suctioned, wherein for gripping the vacuum gripper (210) is placed on the proximal cell layer (120 / 110) from the large-area side of the proximal cell layer (120 / 110) and the vacuum gripper (210) suctions the distal cell layer (110 / 120) through the suction holes (131) and thus grips the unit layer (100), and / or at least the proximal cell layer (120 / 110), in particular the cell frame (120), has peripheral gripping access points (132) by means of which the distal cell layer (110 / 120), in particular the polar plate, can be gripped. (110), can be mechanically grasped,wherein, for grasping, the mechanical gripper (210) is applied to the distal cell layer (110 / 120) from its periphery, and the mechanical gripper (210) grasps the distal cell layer (110 / 120) peripherally via the gripping access points (132), and thus the unit layer (100) is grasped peripherally.

7. Stacking method (400) according to one of the preceding claims, characterized in that: • for suction of the unit layer (100) suction nozzle (231) of the vacuum gripper (210) penetrate into suction holes (131) in the unit layer (100), • a sucking proboscis (231) that has penetrated a suction hole (131) is arranged via a fluid-throttling annular gap in the suction hole (131), and / or • the cell frame (120) is formed as a cell layer (120) and / or the unit layer (100) as a cell layer (100) according to one of the following cell layer requirements.

8. Stacking method (400) according to one of the preceding claims, characterized in that the stacking method (400) comprises a pre-assembly method (300), wherein: R. 414452 - 28 - • in a first step a cell frame (120) is positioned on a polar plate (110), • in a second step a first fluid transport structure (140, 144) is placed within the cell frame (120) on the polar plate (110), • in a third step a membrane (150) is placed on the first fluid transport structure (140, 144) and a radial (Rr) inner rim (122) of the cell frame (120), and / or • in a fourth step a second, possibly multilayer, fluid transport structure (140, 142) is placed on the membrane (150).

9. Cell layer (110 / 120, 100), in particular polar plate (110), cell frame (120), or unit layer (100), for an electrochemical cell stack (10, 60), in particular a fuel cell stack (10) or an electrolysis cell stack (60), comprising a radial (Rr) outer section (116 / 126) completely circumferentially (Ur) the cell layer (110 / 120, 100), within which an electrochemical single cell (11, 61) for the cell stack (10, 60) can be assembled (110) or received (120), characterized in that a stacking device with a plurality of stacking devices (131, 132) is provided on / in the radial (Rr) outer section (126), by means of which the cell layer (110 / 120, 100) is picked up by a gripper (210), in particular a vacuum gripper (210) and / or mechanical gripper (210), graspable (410), reachable (420) and / or stackable (430).

10. Cell layer (110 / 120, 100) according to the preceding claim, characterized in that the stacking devices (131) of the stacking device are designed as suction holes (131) for a vacuum gripper (210), wherein the suction holes (131) are arranged radially outside a sealing surface for a peripheral seal (135) or radially outside a peripheral seal (135) in the radial (Rr) outer section (126) of the cell layer (110 / 120), and / or the stacking devices (132) of the stacking device serve as gripping access points (132) are designed for a mechanical gripper (210), wherein the gripping accesses (132) are formed as material recesses or wall steps in an Au- R. 414452 - 29 - outer circumferential margin in the radial (Rr) outer section (116, 126) of the cell layer (110 / 120) are established.

11. Cell layer (110 / 120, 100) according to the preceding claim, characterized in that suction holes (131): • are located in a periphery and / or the corner areas of the cell layer (110 / 120), • are set up as through holes (131) and / or as blind holes (131) in the cell layer (110 / 120), • have a diameter in the centimeter and / or millimeter range, and / or • at least or exactly: are arranged in a simple, double, triple, quadruple or multiple mirror-symmetrical arrangement in the cell position (110 / 120).

12. Cell layer (110 / 120, 100) according to one of the preceding claims, characterized in that gripping access points (132): • are located in an outer circumferential border in the radial outer section (116 / 126) and / or in the corner areas of the cell layer (110 / 120), • are formed as material recesses and / or wall steps of the cell layer (110 / 120), and / or • at least or exactly: are arranged in a simple, double, triple, quadruple or multiple mirror-symmetrical arrangement in the cell position (110 / 120).

13. Cell layer (100) according to one of the preceding claims, characterized in that the cell layer (100) is designed as a unit layer (100) with two cell layers (110, 120), wherein a first cell layer (110) is designed as a polar plate (110), in particular a bipolar plate (110), and a second cell layer (120) is designed as a cell frame (120) with an electrochemical single cell (11, 61) arranged therein, wherein: • the polar plate (110) and / or the cell frame (120) of the unit layer (100) comprises a stacking device of the unit layer (100), with the plurality of stacking devices (131, 132), • the electrochemical single cell (11, 61) on the polar plate (110) comprises a membrane (150) between two fluid transport structures (140; 144, 142), and / or R. 414452 - 30 - • the membrane (150) is placed on a radial (Rr) inner rim (122) of the cell frame (120).

14. Cell layer (100) according to the preceding claim, characterized in that: • Suction holes (131) in the relevant cell layer (120 / 110) are arranged in the unit layer (100) and are fluid-sealed relative to the other cell layer (110 / 120), • a relevant grasping access (132) is realized in only one cell layer (110 / 120) or as a combined grasping access through both cell layers (110, 120), and / or • the cell layer as a unit layer (100) can be stacked and / or stacked by a stacking method (400) according to one of the preceding claims.

15. Electrochemical cell stack (10, 60), in particular fuel cell stack (10) or electrolysis cell stack (60); electrochemical unit (1, 51), in particular fuel cell unit (1) or electrolyzer unit (51); or electrochemical system, in particular fuel cell system or electrolyzer system, with a plurality of cell layers (100; 110, 120), characterized in that the cell stack (10, 60), or a cell stack (10, 60) of the unit (1, 51) or of the system is constructed by a stacking method (400) according to one of the preceding claims, and / or cell layers (100; 110, 120) of the cell stack (10, 60), of the unit (1, 51) or of the system are formed according to one of the preceding claims.

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