Inspection during the manufacture of modules or module precursors

Abstract

An inspection device (100) for layer material for the manufacture of fuel or battery cells, wherein: - a first layer conveyor (150) is provided and equipped to receive each individual anode or cathode layer (AL, KL) and bring it to a first delivery point (A1); - a stacking table (400) is provided and equipped to receive each individual anode or cathode layer (AL, KL) at the first delivery point (A1) to form a layer stack; - the first layer conveyor (150) is provided and equipped to deliver each individual anode or cathode layer (AL, KL) to the stacking table (400) at the first delivery point (A1);and- a fourth image sensor (K4) is aligned and set up for image acquisition on a fourth area (E4) of the stack of layers consisting of anode and cathode layers (AL, KL) in a planar side view of the stack of layers, after the anode or cathode layer (AL, KL) has been placed on the stacking table (400) on the stack of layers, wherein the fourth area (E4) comprises a corner of an anode or cathode layer (AL, KL) located at the top of the stack of layers and / or a vertical edge (HK) of the stack of layers;and- a fifth image sensor (K5) is aligned and set up for image acquisition on a fifth area (E5) of a stack of anode and cathode layers (AL, KL) in a planar side view of the stack of layers, after the anode or cathode layer (AL, KL) has been placed on the stack of layers on the stacking table (400), wherein the fifth area (E5) comprises a corner of an anode or cathode layer (AL, KL) located at the top of the stack of layers and / or a vertical edge (HK) of the stack of layers; wherein- the fourth area (E4) or the fifth area (E5) of the anode or cathode layer (AL, KL) in the layer surface comprise adjacent or diagonally adjacent areas of the layer stack of anode and cathode layers (AL, KL) in a respective side view of the layer stack;and wherein the inspection device is configured to indicate the (un)suitability of the layer stack depending on a signal based on the processing of an image acquisition from the fourth or fifth image sensor.

Description

BackgroundHere, inspection in the manufacture of modules or precursors of modules is disclosed. These modules or precursors thereof may be, for example, layer arrangements containing sheet material, arrangements for fuel or battery cells, or parts for the production thereof. The layer material can comprise electrode layers which are formed as anode layers or as cathode layers. The inspection is disclosed as a method and apparatus. Details of this are defined by the claims. The description also contains relevant details regarding the structure and mode of operation of the inspection and regarding device and method variants.Prior ArtWO 2021 171 946 A1 relates to a stacking table on which laminate stacks of separating films and electrode layer are stacked. A transport unit serves for transporting the separating films and electrode layer and for depositing them on the stacking table. The above inspection device inspects the position of the electrode sheet in the laminate stacks released from the transport unit.JP 2014 07864 A relates to a laminating machine for producing a laminated body from a rectangular film as a positive electrode, a rectangular film as a negative electrode, which are alternately laminated via a rectangular release film.WO 2021 171 946 A1 relates to a checking device for checking the position of the electrode sheet in a laminate in which a release sheet and an electrode sheet are bonded by an adhesive from the release sheet side. An infrared emitter irradiates the laminate with infrared light from the release sheet side. An infrared light sensitive camera captures the infrared light transmitted through the release film and reflected from the electrode layer. A detection unit detects the position of the electrode sheet on the basis of the image captured by the camera.WO 2020 130 184 A1 describes the production of a cell stack of a secondary battery. A stacking table is reciprocally movable. A separator supply unit is positioned on the stacking table and supplies a separator to the stacking table. A first multi-head is provided on one side of the stacking table and stacks the electrode layers one by one by depositing the electrode layers on the stacking table moved to one side. A second multiple head is provided on the other side of the lamination table and stacks the electrode sheets on the stacking table moved to the other side.Document DE 10 2015 218 138 A1 relates to a sheet processing machine which is configured for depositing sheets on a sheet stack. For setting various actuating means for setting a depositing speed for the sheets to be deposited, a release location for the sheets to be deposited and a positioning of a sheet brake, the depositing of the sheets can be monitored by means of camera sensors.Technical ProblemProceeding from this, a cost-effective and robust arrangement of a stacking unit and a procedure for stacking sheet material at a high processing speed should be provided in order to produce modules or precursors of modules, for example fuel or battery cells containing sheet material, with high precision.Proposed solutionTo solve this problem, inspection apparatuses and inspection methods according to the independent apparatus and method claims are proposed.The solutions for inspection presented here can be integrated into a handling (device or method) in which the stack table moves back and forth and is fed at the respective end positions by one of two layer conveyors with in each case one anode or cathode in order to form the electrode stack. The back and forth movement of the stacking table between the first and the second delivery point limits the number of anode and cathode layers to be deposited per unit time. A solution presented here, which is / the respective pick-ups of the one layer reversing device to be pulled back radially when approaching the / the pick-ups of the other layer reversing device, in particular in the space between the two layer reversing devices, allows a smaller distance between the first and the second delivery point than in the case of a circular trajectory of the pick-ups of both layer reversing devices, which may not touch one another. The length of the travel path of the stacking table between the two delivery points can thus be reduced. This is also relevant in particular after the pick-ups have deposited the anode and cathode layers on the deposit of the stacking table (position 6 o'clock in FIG. 1 ) and the empty pick-ups enter the space between the two layer turn-ups. Without this radial retraction of the receivers, their trajectories would be significantly greater, which would result in an increased distance between the first and second delivery sites. In addition, a more compact design of the entire device is thus possible. Overall, in one variant, the pick-ups of the two layer inverters each move on an approximated, vertical ellipse, the (vertical) main axes of which extend from the center of the respective transfer point to the center of the respective delivery point, and the (horizontal) secondary axes of which do not touch one another. Guiding the pickers along these approximately elliptical paths avoids a collision of the pickers when rotating from the delivery point back to the transfer point, although the two layer turnover devices are arranged close to one another in order to keep the path of the stacking table from one layer turnover device to the other as short as possible.In a variant of the device, the first and the second layer reversing device are provided and configured to move the pick-ups out by means of their respective second drive when the pick-ups approach the respective first or second transfer point and / or the first or second delivery point. For receiving the anode or cathode layers at the respective transfer points (12 o'clock or 6 o'clock position in FIG. 1 ), the receivers of the two layer inverters can be radially extended. The radial movement of the receivers begins before the receivers reach the 6 or 12 o'clock position, and not only in the position reached.This increases the accuracy of the location of the pick-up of the anode or cathode layers from the two conveyors at the respective transfer points. This allows a higher number of anode or cathode layers per unit time on the support of the stack table without impairing the accuracy of the construction of the electrode stack.In a variant of the device, an endless separator is fed from above in the space between the two layer turners, which separator is folded in a Z-shape on the stacking table. The stack table moves back and forth permanently horizontally between the two deposition positions, so that for an electrode stack, starting with the separator and then alternately the anode and cathode layers, respectively, always separated by the folded separator, are deposited alternately on the stack table by the two layer inverters.In a variant of the device, the first conveyor and the second conveyor are arranged adjacent to and at a distance from one another. In a variant of the device, the first conveyor and / or the second conveyor are designed as belt conveyors, which with their respective underside face the first or second layer inverter in order to convey the individual anode layers or the individual cathode layers on their underside to the first or the second transfer point.In a variant of the device, the first conveyor and / or the second conveyor each have a controlled under / over pressure conveyor belt. They are provided and configured to receive the individual anode layers or the individual cathode layers by means of controlled pneumatic negative pressure and to hold them during the conveying to the first or the second transfer point. In a variant of the device, the individual anode layers or the individual cathode layers are to be delivered to the first or second layer reversing device in the first or second transfer point by means of a controlled pneumatic overpressure, for example in the form of a short blow joint.In a variant of the device, the first and / or the second layer inverter each have a plurality of receivers for receiving the individual anode or cathode layers. The pick-ups are provided for this purpose and are configured to rotate successively past the respective transfer point and the respective delivery point continuously or in a clocked manner. In this case, the pick-ups of the first and / or second layer inverter can pick up or deliver the respective individual anode or cathode layer.The angle of rotation of the first and / or the second layer inverter is, for example, approximately 180°. However, it may also be less (for example 90°) or more (for example 270°). The angle of rotation describes the amount by which a layer is pivoted or turned between the transfer location and the delivery location by the layer conveyor. By picking up a sheet by the sheet inverter from the conveyor, inverting and then depositing it on the stacking table, the sheet is inverted. That is, the free top side of the sheet before being picked up by the pickups, which is remote from the conveyor, is the same free top side of the sheet after being deposited on the stacking table, but with the orientation rotated by the rotation angle (for example, 180°). The rotation of the first or second layer inverter and its pick-up takes place about their respective centers of rotation / axes of rotation.In a variant of the device, the first and the second layer reversing means have essentially a matching structure, a matching function and / or a matching dimension. In a variant of the device, the first and the second layer inverter are provided and configured to rotate clockwise or counter-clockwise by means of their respective first drive in such a way that the individual anode or cathode layers pass from their transfer point to their delivery point while avoiding a space between the first and the second layer inverter. In other words, the individual anode or cathode layers are conveyed "outwards" around the first or second layer reversing device from their transfer point to their delivery point, and not through between the two layer reversing devices.In a variant of the device, the first and the second transfer point between the first conveyor or the second conveyor and the first or the second layer inverter each have a first center, and the first or the second discharge point each have a second center between the first or the second layer inverter and the stacking table. In a variant of the device, these respective first and second centers lie on a straight line which substantially at least approximately intersect a respective rotational center of the first conveyor or of the second conveyor.In a variant of the device, the stacking table has a support for the individual anode and cathode layers. In a variant of the device, the stacking table has a single-axis or multiaxial positioning device which is provided and is designed to move the tray along or about the respective axis(s) in order to align it with the first or second delivery point. This allows precise tapping of the layers on the deposit, which enables reliable production without great losses of misproduced electrode stacks.In a variant of the device, the stack table has at least one first and at least one second clamping finger which are provided and are configured to come into or out of engagement with the respectively uppermost of the anode and cathode layers alternately or simultaneously and / or to urge the respectively uppermost of the anode and cathode layers against the electrode stack on the deposit. In one variant, the tray / stacking table is rotatable with the clamping fingers about a z-axis (vertical axis). In one variant, the tray / stacking table can be positioned with the clamping fingers in the x and / or y direction.In a variant of the device, the first and the second layer reversing device are provided and configured to receive the individual anode layers and the individual cathode layers by means of a controlled pneumatic vacuum and to hold them during the reversing to the first and the second dispensing point. Additionally or instead, by means of a controlled pneumatic overpressure, the individual anode layers and the individual cathode layers are to be dispensed in the first and the second dispensing location, respectively, in order to stack the layers on the deposit.In a variant of the device, the first and the second layer reversing means each have a rotatable over / under pressure distribution which is provided and is designed to feed the pick-ups with the controlled pneumatic negative pressure and / or positive pressure. In a variant of the device, the first and the second layer reversing means are provided and are configured to respectively reverse only individual ones of the anode layers or only individual ones of the cathode layers towards the first or the second delivery point.In a variant of the device, each adjusting device is provided and is configured to lower the support during stacking of the individual anode layers and individual cathode layers by a distance which substantially corresponds to a thickness of an individual anode layer or an individual cathode layer.In a variant of the device, the first drive is designed as a rotary drive which is provided and configured to turn the pick-up of the layer turner. In a variant of the device, the second drive has a rotary drive with an eccentric shaft coupled in a driven manner to the pick-ups in order to retract and / or extend the pick-up of the respective layer reversing device radially. Alternatively, the second drive has a linear drive which is coupled in a driven manner to one of the receivers in order to retract and / or extend the receivers of the respective layer reversing device radially.A method for producing modules or precursors of modules, in particular fuel or battery cells containing layer material, carried out, for example, with the device explained above, comprises, for example, in the following sequence the steps: conveying individual anode layers to a first transfer point for transferring to a first layer inverter; conveying individual cathode layers to a second transfer point for transferring to a second layer inverter; receiving respective individual anode or cathode layers at the respective first or second transfer point by means of corresponding receivers of a respective first or second layer inverter; inverting the received individual anode or cathode layers by a respective angle of rotation to a respective first or second transfer point; Reciprocating a stacking table with a drive between the first and second delivery locations; delivering the respective single anode and cathode layers to the stacking table at the first and second delivery locations, respectively, when at the first and second delivery locations, respectively; and radially retracting the picker of the first and / or second layer inverter as it approaches the picker of the other layer inverter.This approach of the pick-up of one layer reversing device to the pick-up of the other layer reversing device is relevant in particular in the space between the two layer reversing devices when the pick-up approaches a pick-up of the other layer reversing device on the path from its delivery point to its delivery point or from its delivery point to its delivery point.A first variant of the inspection device for sheet material, in particular for producing fuel or battery cells, has a first sheet conveyor and a first drive and is provided and configured to pick up a respective individual anode or cathode sheet from a first transfer point by means of the at least one pick-up and to bring it to a first discharge point. In this variant, the first layer conveyor is provided and configured to respectively discharge a single anode or cathode layer from its pick-up to the stacking table at the first discharge point when the respective at least one pick-up is located at the first discharge point. In this variant, at least one drive is provided in order to align the pick-up and the stacking table relative to one another as a function of signaling based on processing of the first and / or second image feed. In this variant, a first image pick-up is aligned with a first region of the first layer conveyor between the first transfer point and the first delivery point and is provided and configured for a first image input when the at least one pick-up of the first layer conveyor passes the first image pick-up. In this variant, alternatively or cumulatively, a second image pick-up is aligned between the first transfer point and the first delivery point with a second region of the first layer conveyor and is provided and configured for a second image entry when the at least one pick-up of the first layer conveyor passes the second image pick-up. In this variant, a stack table is provided and is configured to receive the respective individual anode or cathode layer at the first delivery point in order to form a layer stack.In one variant, the first layer conveyor comprises a layer inverter which is provided and configured to receive a respective individual anode or cathode layer from the first transfer point by means of the at least one pick-up and to rotate a respective angle of rotation to a first discharge point.In one variant, the first layer conveyor comprises a layer gripper which is provided and configured to pick up a respective individual anode or cathode layer from the first transfer point and to bring it to the first delivery point by means of a pick-up, for example in the form of a suction or gripping tool.In a variant, a second layer conveyor is provided and configured to receive a single cathode or anode layer and to bring it to a second delivery location. In a variant, a first image pickup is aligned with a first region of the second layer conveyor between the second transfer point and the second delivery point and is provided and configured for a first image pickup when the second layer conveyor passes the first image pickup. Alternatively or cumulatively, in a variant, a second image pick-up is aligned between the second transfer point and the second delivery point with a second region of the second layer conveyor and is provided and configured for a second image intake when the second layer conveyor passes the second image pick-up.In one variant, the second layer conveyor comprises a layer inverter which is provided and configured to receive a respective individual anode or cathode layer from the second transfer point by means of the at least one pick-up and to rotate a respective angle of rotation to a second discharge point.In one variant, the second layer conveyor comprises a layer gripper which is provided and configured to pick up a respective individual anode or cathode layer from the second transfer point and to bring it to the second discharge point by means of a pick-up, for example in the form of a suction or gripping tool.In one variant, the stacking table is assigned a drive which is provided and is configured to drive the stacking table back and forth between the first and the second delivery point. In one variant, the first and the second layer conveyor are each provided and configured to discharge a single anode or cathode layer to the stacking table at the first or the second discharge point. In one variant, at least one drive is provided in order to align the respective layer conveyor and / or the respective at least one layer inverter or layer gripper relative to the stacking table as a function of signaling based on processing of the first and / or second image feeding in a controller. This drive can be designed as an additional drive in the Y direction and / or as a rotary drive about the z axis in.theta. for the storage area.In a variant, the first region and the second region of the at least one pick-up of the layer inverter are corner regions of the at least one pick-up of the layer inverter lying diagonally with respect to one another. In a variant, the first corner region and the second corner region of the at least one receiver of the layer inverter are provided and configured to receive a first corner and second corner, respectively, of the individual anode or cathode layer. In one variant, the first and / or the second image pick-up are oriented between the transfer point and the delivery point onto the first or second corner region of the pick-up at the time of the first or second image acquisition at an angle of approximately 30° to approximately 150°, or at an angle of approximately 60° to approximately 120°, at an angle of approximately 80° to approximately 100°, or at an angle of approximately 90°, with respect to the surface of the pick-up in the respective region.In one variant, the first and / or the second image pickup can be adjusted along their optical axes for focusing and / or can be moved during operation. In one variant, a white light source assigned to the first and / or the second image recorder is intended and configured to lighten the anode / cathode layer for image introduction by the first and / or the second image recorder. In one variant, at least one optically active element is assigned to the first and / or the second image pickup in each case; wherein the optically active element is intended and configured to record the position and / or orientation of the anode / cathode layer at one or more locations or regions before or upon arrival at the emission location or on the way to the emission location; and / or wherein the at least one optically active element is a lens, or lens arrangement, a mirror or mirror arrangement, a prism or prism arrangement, a light guide arrangement, a surface light, a coaxial ring light, a dark field light, or combinations thereof.In one variant, the control unit is determined and configured to determine correction values from the image input or the image inputs from the position and / or orientation of the anode / cathode layer before it is picked up by the stack table, the position and / or orientation of the stack table, and / or the position and / or orientation of the picked-up individual anode / cathode layer relative to the stack table during the turning of the anode / cathode layer to the stack table. In one variant, the control unit is determined and configured to take into account these correction values during the alignment of the stack table with the transported anode / cathode layer relative to the deposition location in actuating commands to the layer inverter, the pick-up and / or the stack table. In one variant, the control unit is determined and configured to take into account these correction values for the alignment and the location of the stack table when recording the anode / cathode layer in actuating commands to the layer inverter, the pick-up and / or the stack table in such a way that the stack table records the respective anode / cathode layer in a central zero position and / or aligned with the electrode stack located at the delivery point. In one variant, the control unit is intended and configured to determine the orientation and the location of the stack table during or before the recording of the anode / cathode layer by checking the position of the arriving anode / cathode layer in the image inlets directly before the delivery point.In one variant, the pick-up is radially movable relative to its axis of rotation, and the first image pick-up and / or the second image pick-up is configured for a first or second image entry, respectively, when the pick-up moves radially outwards or inwards.A variant of an inspection method in the production of modules or precursors of modules comprises the steps of: picking up an anode / cathode layer from a transfer point; bringing the anode / cathode layer from the transfer point to a delivery point; detecting the position and / or orientation of the anode / cathode layer on the layer inverter by means of a first image recorder between the transfer point and the delivery point, wherein the first image recorder is aligned with a first region of the layer inverter and is provided and configured to a first image recorder when the anode / cathode layer on the layer inverter passes the first image recorder.In a variant of the inspection method, a position and / or orientation of the anode / cathode ply is detected on the ply inverter by means of a second image recorder between the transfer point and the delivery point, wherein the second image recorder is aligned with a second region of the ply inverter and is provided and configured for a second image registration when the at least one recorder of the ply inverter passes the second image recorder. In a variant of the inspection method, the pick-up and the stack table are aligned relative to one another as a function of signaling based on processing of the first and / or second image registration. In a variant of the inspection method, the respective individual anode or cathode layer is discharged from the respective at least one pick-up at the discharge point onto the stack table to form a layer stack when the respective at least one pick-up is located at the discharge point.In a variant of the inspection method, the first and / or the second image pick-up in a perpendicular, ±approximately 25°, plan view (based on the surface of the anode / cathode layer) of the anode / cathode layer record its position and / or orientation in x, y, z and / or theta when the at least one pick-up of the layer reversing means passes the respective image pick-up. In a variant of the inspection method, a light source assigned to the first and / or the second image recorder illuminates the anode / cathode layer for image introduction through the first and / or the second image recorder. In a variant of the inspection method, the first and / or the second image pickup device completely record the anode / cathode position with an image inlet in order to record its position and / or orientation in x, y, z, and / or theta. In a variant of the inspection method, the first and / or the second image pickup, relative to a respective defined image pickup zero point, record with a single image entrance a region, at least one corner region, two diagonal corner regions, and / or at least one corner region and at least one portion of an edge of the anode / cathode layer in order to record the position and / or orientation in x, y, z, and / or theta of the anode / cathode layer. In a variant of the inspection method, the first and / or the second image pickup device are designed as a matrix camera or as a line camera, which record the position and / or orientation in x, y, z, and / or theta of the anode / cathode layer before or upon their arrival at the delivery point or on the path to that of the delivery point.In a variant of the inspection method, correction values are determined from the position and / or orientation in x, y, z, and / or theta of the anode / cathode layer after it has been picked up by the at least one pick-up of the layer inverter, the position and / or orientation in x, y, z, and / or theta of the stack table, and / or the position and / or orientation in x, y, z, and / or theta of the picked-up individual anode / cathode layer during an inversion of the anode / cathode layer to the stack table. In a variant of the inspection method, these correction values are taken into account when aligning in x, y, z and / or theta the pick-up of the layer inverter with the transported anode / cathode layer relative to the stacking table at the delivery point. In a variant of the inspection method, these correction values in x, y, z and / or theta are taken into account when aligning the pick-up of the layer inverter in such a way that the anode / cathode layer is picked up by the stacking table in a central zero position and / or aligned.With the first type of inspection proposed here during cell production with the first and second image pick-ups (cameras) by means of the first and second image pick-ups, the electrode layers are stacked one on top of the other as exactly as possible. Thus, the highest possible efficiency of the finished fuel or battery cells can be achieved. The less accurate the electrode layers are stacked, the lower the efficiency becomes. The inspection proposed here detects the exact position of the electrode layer (during the turning, that is to say) directly before the stacking. From this position, a measure for correcting the relative position between the stacking table and the pick-up of the layer reversing device is determined and applied. Thus, the accuracy of the deposition of the individual electrode layer on the growing stack is as precise as possible. This approach avoids production waste and higher efficiencies of the finished fuel or battery cells can be achieved.In a variant, the first and the second corner region of the inspected electrode and of the layer inverter are different. In one variant, a stack table is provided and configured to receive the respective individual anode or cathode layer at the first delivery point in order to form a layer stack.In one variant, the first corner region and the second corner region of the first layer turner are regions of the first layer turner that are diagonally to one another. In one variant, the first corner region and the second corner region are two (approximately equally sized) surface regions of the at least one pick-up of the first layer reversing device when this pick-up is located on the path between the first transfer point and the first delivery point.In a variant, the first corner region and the second corner region of the at least one receiver of the first layer conveyor are provided and configured for receiving a first corner and a second corner, respectively, of the individual anode or cathode layer.In one variant, the first and / or second image pick-up between the first / second transfer point and the first / second delivery point is aligned with the first or second corner region of the first / second layer conveyor at the time of the first and / or second image pick-up at an angle of about 25° to about 150°, or at an angle of about 60° to about 120°, or at an angle of about 80° to about 100°, or at an angle of about 90° (with respect to the surface of the anode / cathode layer or of the first / second pick-up).In variants of the inspection, the first and / or the second camera acquire, in a vertical, ±approximately 25° to ±30 °, plan view of the anode / cathode layer, their position and / or orientation on the respective pick-up (with respect to the surface of the anode / cathode layer or of the first / second pick-up) when it passes the respective image pick-up. In variants of the inspection, the first and / or the second image pickup can be adjusted for focusing along their optical axes and / or can be moved during operation.In variants of the inspection, a white light source assigned to the first and / or the second image recorder illuminates the anode / cathode layer for image introduction through the first or second image recorder. In variants of the inspection, the first and / or the second camera completely record the anode / cathode layer with a (single) image input in order to record their position and / or orientation.In variants of the inspection method, the first and / or the second camera acquire a region, at least one corner region, two diagonal corner regions, and / or at least one corner region and at least one portion of an edge of the anode / cathode layer with a single image input in order to acquire the position and / or orientation of the anode / cathode layer.In variants of the inspection, the first and / or the second camera are configured as a matrix camera or as a line camera, which record the position and / or orientation of the anode / cathode layer during the turning over toward the stacking table.In variants of the inspection, correction values are determined from the position and / or orientation of the anode / cathode layer on the pick-up during the turning of the anode / cathode layer toward the delivery point on the stacking table. These correction values are taken into account in variants of the inspection when aligning the stack table relative to the pick-up with the transported anode / cathode layer at the deposition location.In variants of the inspection, these correction values are taken into account when aligning the stack table for receiving the anode / cathode layer by the stack table in such a way that the anode / cathode layer is received by the stack table in a central zero position and / or aligned.During the inspection, in one variant, the stacking device can be positioned relative to the anode / cathode layer before / during its deposition on the stacking table with the calculated correction values in such a way that the anode / cathode layer is received by the stacking table positioned in a zero position. For this purpose, the stack table can be corrected in its position and / or orientation with respect to the anode / cathode layer / with respect to the layer conveyor at the delivery point. Likewise, after being picked up during transport according to the correction values from the image holder, the stack table can be positioned such that the anode / cathode layer is deposited by the stack table when it is deposited at the deposition point on the electrode stack located there, the anode / cathode layer is matched and deposited with minimal or no further correction movement. This can be carried out very quickly and with high precision. For inspection, for example, an apparatus explained below is suitable.In variants of the inspection, one (white) light source or sources assigned to the camera(s) are intended and configured to lighten the anode / cathode position for image registration by the respective camera.In variants of the inspection, at least one optically active element is connected upstream of one or all camera(s), is intended and configured to record the position and / or orientation of the anode / cathode layer at one or more locations or regions before being recorded by the pick-up or upon its arrival at the delivery point or on the way to the delivery point. In variants of the device, the at least one optically active element is a lens, or lens arrangement, a mirror or mirror arrangement, a prism or prism arrangement, a light guide arrangement, a surface light, a coaxial ring light, a dark field light, or combinations thereof. In variants of the inspection, a control unit is determined and configured to determine correction values from the image input and / or data from the detection device and / or the first and / or the second camera from the position and / or orientation of the anode / cathode layer before it is recorded by the stack table, the position and / or orientation of the stack table, and / or the position and / or orientation of the recorded individual anode / cathode layer relative to the stack table during a turning of the anode / cathode layer to the stack table.In variants of the inspection, the control unit is determined and configured to take into account these correction values during the alignment of the stack table with the transported anode / cathode layer relative to the delivery point in adjustment commands to the layer turner and / or its pick-up and / or the stack table. In variants of the inspection, a control unit is determined and configured to take into account the alignment and the location of the stack table when recording the anode / cathode position in actuating commands such that the stack table records the respective anode / cathode position in a central zero position and / or aligned with the electrode stack located at the delivery point.By checking the position of the incoming anode / cathode layer immediately before the delivery location, the alignment and location of the stack table during or before receiving the anode / cathode layer is to be determined accurately. This allows a precisely determined, corrected recording of the anode / cathode layer by the stack table to form a stack of electrode layers which is exactly aligned in the vertical extension and the angular position about the vertical axis.In a second variant, an inspection device for sheet material, in particular for producing fuel or battery cells, comprises a first sheet conveyor, which has at least one pick-up and a first drive and is provided and configured to pick up a respective individual anode or cathode sheet from a first transfer point by means of the at least one pick-up and to bring it to a first discharge point. In one variant, a stack table is provided and configured to receive the respective individual anode or cathode layer from the receiver at the first delivery point in order to form a layer stack. In a variant, the first layer conveyor is provided and configured to discharge a single anode or cathode layer from its pick-up to the stacking table at the first discharge point when the pick-up is located at the first discharge point. In a variant, a third image pickup is directed at a region comprising an upper edge of a layer stack located on the stack table in a side view of the layer stack, which region comprises a connection lug of an anode or cathode layer located at the top on the layer stack, and is provided and configured for a third image registration before and / or after the anode or cathode layer is deposited on the stack table. In one variant, a controller is provided and configured to indicate the (un)time of the layer stack as a function of signaling based on processing of the third image acquisition. This can be followed by (automated) removal of the stack.In one variant, the layer conveyor comprises a layer inverter which is provided and configured to receive a respective individual anode or cathode layer from the first transfer point by means of the at least one pick-up and to rotate a respective angle of rotation to a first discharge point.In a further variant, the layer conveyor comprises a layer gripper which is provided and configured to pick up a respective individual anode or cathode layer from the first transfer point and to bring it to the first delivery point by means of the one pick-up, for example in the form of a suction or gripping tool.In a further variant, the inspection device comprises a second layer conveyor which is provided and configured to receive a single cathode or anode layer and to bring it to a second delivery point. In one variant, the stacking table is assigned a drive which is provided and is configured to drive the stacking table back and forth between the first and the second delivery point. In one variant, the first and the second layer conveyor are each provided and configured to discharge a single anode or cathode layer to the stacking table at the first and the second discharge point, respectively. In one variant, at least one drive is provided in order to align the respective layer conveyor and / or a respective at least one layer inverter or layer gripper relative to the stacking table as a function of signaling based on processing of the first and / or second image feeding in a controller.In one variant, the second layer conveyor comprises a layer inverter which is provided and configured to receive a respective individual anode or cathode layer from the second transfer point by means of the at least one pick-up and to rotate a respective angle of rotation to a second discharge point.In one variant, the second layer conveyor comprises a layer gripper which is provided and configured to pick up a respective individual anode or cathode layer from the second transfer point by means of a pick-up, for example in the form of a suction or gripping tool, and to bring it to the second discharge point.In a variant, a first third region and a second third region of the layer stack each comprise a terminal tab of the respectively uppermost anode or cathode layer on the stack table at the first and the second delivery point, respectively. In one variant, one or two third image pickups are arranged on a first side of the inspection device, and one or two third image pickups are arranged on a second side of the inspection device. In one variant, one or more third image pickups are arranged in a fixed position relative to the movable stacking table. In one variant, one or more third image pickups are connected to the stacking table in order to be movable therewith.In a variant of the inspection device, the at least one third image pickup is adjustable along its optical axis for focusing and / or is movable during operation. In one variant, a light source assigned to the third image recorder is intended and configured to lighten the anode / cathode layer for image introduction by the third image recorder. In one variant, at least one optically active element is assigned to the at least one third image sensor. In one variant, the optically active element is intended and configured to make the connection lug of an anode or cathode layer located at the top on the layer stack recognizable in the third image insert after the anode or cathode layer is deposited on the layer stack. In a variant, the at least one optically active element is a lens, or lens arrangement, a mirror or mirror arrangement, a prism or prism arrangement, a light guide arrangement, a surface light, a coaxial ring illumination, a dark field illumination, a transmitted light illumination, or a combination thereof.In transmitted light illumination, the light is opposite to the viewing direction of the image recorder. The light does not pass through the material of the terminal lug, as is the case, for example, with a semiconductor chip with IR light.In a variant of the inspection device, the transmitted light illumination is arranged on the opposite side of the third image pickup beyond the position of the connection lug on the stacking table and is configured to take the connection lug into the light beam path. Thus, by processing the third image registration, a lifting of the connection lug can be detected in that the uppermost edge of the connection lug in the image registration is not substantially horizontal (<±10° relative to the horizontal or to the optical axis of the respective third image pickup), or oriented planarly with the electrode and / or causes an interference contour.In a variant of the inspection device, the coaxial ring illumination is arranged on the side of the third image pickup on this side of the position of the connection lug on the stacking table and is configured to take the connection lug into the light beam path in order to detect lifting of the connection lug by means of processing of the third image pickup in that the uppermost edge of the connection lug in the image pickup is not oriented (<±10° relative to the horizontal or to the optical axis of the respective third image pickup), or is oriented planarly with the electrode and / or causes a disturbing contour.A second inspection method in the production of modules or precursors of modules comprises the steps of: receiving an anode / cathode layer at a first transfer location and bringing the anode or cathode layer from the first transfer location to a first transfer location; transferring the respective individual anode or cathode layer at the transfer location onto a stack table to form a layer stack; directing a third image recorder onto a region comprising an upper edge of a layer stack located on the stack table in a side view, wherein the region comprises a connection tab of an anode or cathode layer located uppermost on the layer stack; and wherein a third image registration is performed by means of the third image pickup after the anode or cathode layer is deposited on the stacking table; and indicating a (un)light of the layer stack depending on a signaling based on a processing of the third image registration.In one variant, the inspection method further comprises the steps of: adjusting the at least one third image pickup for focusing along its optical axis and / or moving the at least one third image pickup for focusing along its optical axis during operation; and / or lightening the anode / cathode layer for a third image pickup by means of a light source assigned to the at least one third image pickup; and / or assigning at least one optically active element to the at least one third image pickup; wherein the optically active element is determined and configured to make the connection lug of an anode or cathode layer located uppermost on the layer stack recognizable in the third image pickup in a side view after the anode or cathode layer is deposited on the layer stack; and / or wherein the at least one optically active element is a lens, or lens arrangement, a mirror or a mirror arrangement, a prism or a prism arrangement, a light guide arrangement, a surface light, a coaxial ring illumination, a dark field illumination, a transmitted light illumination, or a combination thereof.In a variant, the inspection method further comprises the steps of: arranging the transmitted light illumination on the opposite side of the at least one third image pickup, beyond the position of the connection lug on the stacking table, and for setting the at least one third image pickup to take the connection lug into the light beam path; in order to detect, by means of processing of the third image pickup, a lifting-off of the connection lug in which the uppermost edge of the connection lug does not orient itself (<±10° relative to the horizontal or to the optical axis of the respective third image pickup), or orients itself flatly with the electrode and / or causes a disturbing contour.In a variant, the inspection method further comprises the steps of: arranging the coaxial ring illumination on the side of the at least one third image pickup, this side of the position of the connection lug on the stacking table, and for setting the at least one third image pickup to take the connection lug into the light beam path; detecting, by means of processing of the third image pickup, a lifting-off of the connection lug by the uppermost edge of the connection lug in the third image pickup not being horizontally (<±10° relative to the horizontal or to the optical axis of the respective third image pickup), or being oriented flatly with the electrode and / or causing a disturbing contour.With the further, second inspection proposed here during cell production using the at least one third image recorder (camera), the orientation of the connection tab of the uppermost electrode layer to the connection tab / s lying thereunder is also monitored.This further inspection is to be realized alternatively or additionally to the first inspection. Thus, a possible failure or loss of efficiency of the finished fuel or battery cells is to be avoided. When stacking an electrode layer, it also happens that its terminal tab is set up, bulges or bulges and the risk is thereby created that they are kinked, for example also when stacking the next electrode layer of the same polarity. If the terminal lugs are not connected to one another over their entire surface, the efficiency of the fuel cell or battery cell decreases. If a terminal tab is bent over the release foil and comes into contact with the counter electrode layer, this may cause a short circuit of the cell. The inspection proposed here detects the exact orientation of the terminal tabs of each electrode layer immediately after the stacking. From this position, a measure for correcting the relative position between the stacking table and the pick-up of the layer reversing device is determined and applied. Thus, the accuracy of the deposition of the individual electrode layer on the growing stack becomes as precise as possible to the electrode stack already located on the stack table. Thus, less scrap can be produced and a higher efficiency can be achieved.A further, third inspection of cell production comprises, for example in the following order, the steps of: providing a single anode / cathode layer; conveying the anode / cathode layer to a delivery location; stacking the conveyed anode / cathode layer on a stack table at the delivery location; detecting an electrode stack grown around the stacked anode / cathode layer at the delivery location in at least one side view of a corner and / or a top edge of the electrode stack at the delivery location; and checking the orientation and / or position of the or each stacked anode / cathode layer relative to the remaining electrode stack grown at the delivery location.This can be achieved with an inspection device for sheet material, in particular for producing fuel or battery cells, in a third variant, in which: a first sheet conveyor is provided and configured to receive a respective individual anode or cathode sheet and to bring it to a first delivery point; a stacking table is provided and configured to receive the respective individual anode or cathode sheet at the first delivery point to form a sheet stack; the first sheet conveyor is provided and configured to deliver a respective individual anode or cathode sheet to the stacking table at the first delivery point; and a fourth image sensor is aligned with a fourth region of the layer stack of anode and cathode layers in a planar side view of the layer stack and is provided and configured for image introduction after the anode or cathode layer is deposited on the layer stack on the stack table, wherein the fourth region comprises a corner of an anode or cathode layer located uppermost on the layer stack and / or a top edge of the layer stack; and / or a fifth image recorder is aligned with a fifth region of the layer stack of anode and cathode layers in a planar side view of the layer stack and is provided and configured for image introduction after the anode or cathode layer is deposited on the layer stack on the stack table, wherein the fifth region comprises a corner of an anode or cathode layer located uppermost on the layer stack and / or a top edge of the layer stack; the fourth region or the fifth region of the anode or cathode layer comprises regions of the layer stack of anode and cathode layers located adjacent or diagonally to one another in the layer surface in a respective side view of the layer stack.The fourth and the fifth region are, in a variant, mutually different regions of the layer stack on the stacking table.In one variant, the layer conveyor comprises a layer inverter which is provided and configured to receive a respective individual anode or cathode layer from the first transfer point by means of at least one pick-up and to rotate a respective angle of rotation to the first discharge point.In one variant, the layer conveyor comprises a layer gripper which is provided and configured to pick up a respective individual anode or cathode layer from the first transfer point by means of a pick-up, for example in the form of a suction or gripping tool, and to bring it to the first delivery point.In one variant, the fourth image pickup and / or the fifth image pickup can be adjusted along their optical axis for focusing and / or can be moved during operation. In one variant, a light source assigned to the fourth image recorder and / or the fifth image recorder is respectively determined and configured to lighten the anode / cathode position for a fourth image input or a fifth image input by the fourth image recorder or fifth image recorder. In one variant, at least one optically active element is assigned to the fourth image recorder or fifth image recorder. In one variant, the optically active element is intended and configured to make the corner of the anode or cathode layer located on top of the layer stack and / or the top edge of the layer stack recognizable in the fourth image pocket or the fifth image pocket after the anode or cathode layer is deposited on the layer stack. In a variant, the at least one optically active element is a lens, or lens arrangement, a mirror or mirror arrangement, a prism or prism arrangement, a light guide arrangement, a surface light, a coaxial ring illumination, a dark field illumination, a transmitted light illumination, or a combination thereof.In one variant, the transmitted-light illumination is arranged on the opposite side of the fourth image recorder or of the fifth image recorder, beyond the position of the corner of the anode or cathode layer located on the top of the layer stack and / or the top edge of the layer stack, and is configured to take the corner and / or the top edge into the light beam path. In one variant, by processing the fourth image feed or the fifth image feed, lifting, displacing or rotating the anode or cathode layer can be detected, in that the corner and / or the top edge of the anode or cathode layer located on the top of the layer stack causes a disturbing contour in the image feed.In one variant, the coaxial ring illumination is arranged on the side of the fourth image pickup or of the fifth image pickup on this side of the position of the corner of the anode or cathode layer located on the top of the layer stack and / or of the top edge of the layer stack, and is configured to take the corner and / or the top edge into the light beam path. In one variant, by processing the fourth image feed or the fifth image feed, lifting, displacing or rotating the anode or cathode layer can be detected, in that the corner and / or the top edge causes a disturbing contour in the image feed.In a variant, a first fourth region and a first fifth region of the layer stack each comprise a corner of a first, substantially horizontally oriented edge of the anode or cathode layer located uppermost on the layer stack and / or of a top edge of the layer stack on the stack table and / or a second fourth region and a second fifth region of the layer stack each comprise a corner of a second edge of the anode or cathode layer located uppermost on the layer stack and / or of a top edge of the layer stack on the stack table. In one variant, one or more fourth or fifth image pickups are arranged in a fixed position relative to the movable stacking table. In one variant, one or more fourth or fifth image pickups are connected to the stacking table in order to be movable therewith.In a variant, a third inspection method in the production of modules or precursors of modules comprises the steps of: picking up an anode / cathode layer by means of at least one pick-up from a transfer point; dispensing the respective individual anode or cathode layer from the respective at least one pick-up at a dispensing point onto a stack table for forming a layer stack when the respective at least one pick-up is located at the dispensing point; directing a fourth image pick-up onto a fourth region of the layer stack of anode and cathode layers in a planar side view of the layer stack, wherein the fourth region comprises a corner of an anode or cathode layer located uppermost on the layer stack and / or a top edge of the layer stack; performing a fourth image registration after the anode or cathode layer is deposited on the layer stack on the stack table; and / or directing a fifth image capture device onto a fifth region of the layer stack of anode and cathode layers in a side view of the layer stack, wherein the fifth region comprises a corner of an anode or cathode layer located uppermost on the layer stack and / or a top edge of the layer stack; and / or performing a fifth image registration after the anode or cathode layer is deposited on the layer stack on the stack table; and / or wherein the fourth region or the fifth region of the anode or cathode layer in the layer surface comprise regions of the layer stack of anode and cathode layers lying adjacent or diagonally with respect to one another in a respective side view of the layer stack; and indicating a usability of the layer stack depending on a signaling based on a processing of the fourth or the fifth image input.In one variant, the inspection method comprises the steps: setting the fourth or the fifth image pickup for focusing along its optical axis and / or moving the respective image pickup for focusing along its optical axis during operation. In one variant, the fourth or the fifth region for the fourth or the fifth image registration is illuminated by the respective image recorder by means of a light source assigned to the fourth or the fifth image recorder. In one variant, at least one optically active element is assigned to the fourth or the fifth image recorder in order to make the corner of the anode or cathode layer located on the top of the layer stack and / or the top edge of the layer stack recognizable in the fourth or the fifth image holder after the anode or cathode layer is deposited on the layer stack. In a variant, the at least one optically active element is a lens, or lens arrangement, a mirror or mirror arrangement, a prism or prism arrangement, a light guide arrangement, a surface light, a coaxial ring illumination, a dark field illumination, a transmitted light illumination, or a combination thereof.In one variant, the inspection method comprises the steps of: arranging the transmitted light illumination on the opposite side of the fourth or of the fifth image recorder beyond the position of the corner of the anode or cathode layer located uppermost on the layer stack and / or the top edge of the layer stack on the stack table, and for setting up the transmitted light illumination to take the corner and / or the top edge of the layer stack into the light beam path. In one variant, processing of the fourth or the fifth image registration means that an at least partial lifting, displacement or rotation of the anode or cathode layer located on the top of the layer stack is detected, in that the top corner and / or the top edge causes a disturbing contour.In one variant, the inspection method comprises the steps of: arranging the coaxial ring illumination on the side of the fourth or of the fifth image recorder, respectively, this side of the position of the corner of the anode or cathode layer located uppermost on the layer stack and / or of the upper edge of the layer stack on the stack table, and for setting up the transmitted light illumination to take the corner and / or the upper edge of the layer stack into the light beam path. In one variant, processing of the fourth or the fifth image registration means that an at least partial lifting, displacement or rotation of the anode or cathode layer located on the top of the layer stack is detected, in that the top corner and / or the top edge causes a disturbing contour. In one variant, one or more fourth and fifth imagers are oriented at an angle of from about ±5° to about ±5° to a longitudinal or transverse edge of the anode or cathode layer located uppermost on the layer stack, for example ±13°.In one variant, the inspection method for the production of modules or precursors of modules further comprises the steps of: picking up an anode / cathode layer by means of at least one second pick-up of a second layer inverter from a second transfer point; dispensing the respective individual anode or cathode layer from the respective at least one pick-up at a second dispensing point onto the stack table for forming the layer stack when the respective second pick-up is located at the dispensing point; directing a fourth image recorder onto a fourth region of the layer stack of anode and cathode layers in a planar side view of the layer stack, wherein the fourth region comprises a corner of an anode or cathode layer located uppermost on the layer stack and / or a top edge of the layer stack; and carrying out a fourth image registration after the anode or cathode layer has been deposited on the layer stack on the stack table; and / or directing a fifth image recorder onto a fifth region of the layer stack of anode and cathode layers in a planar side view of the layer stack, wherein the fifth region comprises a corner of an anode or cathode layer situated uppermost on the layer stack and / or a top edge (HK) of the layer stack; and carrying out a fifth image registration after the anode or cathode layer has been deposited on the layer stack on the stack table; and / or wherein the fourth region or the fifth region of the anode or cathode layer in the layer surface comprise regions of the layer stack of anode and cathode layers situated adjacent or diagonally to one another in a respective side view of the layer stack; and indicating a (un)signaling of the layer stack depending on a signaling based on a processing of the fourth or the fifth image input.This further, third inspection is to be realized alternatively or additionally to the first and / or the second inspection.This procedure allows precise position determination of the uppermost layer in relation to the remaining layers of the electrode stack. This check is increasingly important as the height of the electrode stack increases, since incorrectly positioned placement of the uppermost layer without further correction must lead to warping of the electrode stack. In this case, the control becomes increasingly more accurate as the height of the electrode stack increases, since the geometric regions to be measured (corner or vertical edge of the electrode stack) can be detected and evaluated more easily and precisely.In a variant of the third inspection, this also allows more accurate correction values to be calculated when depositing the next-following layer on the electrode stack. Overall, this approach with the precise position checking allows a considerable reduction in the risk of short-circuiting, for example of the fuel or battery cells.This is also made clear by the fact that previous solutions only deposit the layers with an accuracy of approximately ±0.5 mm, while the solution presented here allows an accuracy of ±0.1 mm and more accurately when depositing the anode / cathode layers on the electrode stack in order to reduce waste and to improve efficiency.In a variant of the method, four matrix cameras are used, which are directed (viewed from the side) onto all four corners / (high) edges of the electrode stack at the deposition location. In a variant of the method, incident light or background illumination (backlight) or dark field illumination (dark field) is effected by means of respective light sources. The relevant regions of the various anode / cathode layers can thus be easily seen. In a variant of the method, the beam path of the third cameras is guided by mirrors or prisms for adaptation to spatial conditions.In a variant of the method, a matrix camera is used, with a field of view onto the electrode stack from the side which completely captures the electrode stack as a whole in an image input, or two matrix cameras, which each capture one of two corners of the electrode stack from the side, until four matrix cameras, which capture all four corners of the electrode stack from above and which, in the side view, are directed onto the electrode stack at the deposition location. Here too, in a variant, the beam path of the cameras is guided by corresponding arrangements of mirrors or prisms, etc., for adaptation to spatial conditions.In one variant, coaxial (red) illumination and / or a (white) spotlight are used for each of the cameras for the illumination.It can thus be seen very precisely that the anode / cathode layers are always deposited at the correct location and in correct alignment on the electrode stack.In a variant of the method, the movements of the lifting device with the respective workpiece carrier along the vertical axis (z axis) and their inaccuracies are also taken into account in that the x-, y-positions of the workpiece carrier at different z heights are detected with the cameras before the beginning of the depositing of the anode / cathode layers in order to form the electrode stack. Thus, during the deposition of the anode / cathode layers, it can be checked with the cameras whether the anode / cathode layers have been deposited at the correct x-, y-position, which corresponds to the respective z-position of the workpiece carrier on the lifting device. The accuracy in the direction of rotation about the vertical axis (in.theta.) when picking up the anode / cathode layers with the stacking device can also be corrected thereby for a later precise destacking of the anode / cathode layers of the electrode stack.In a variant of the device, a control unit is determined and configured to determine a position of a stacked anode / cathode layer in relation to the remaining layers of the electrode stack by checking the position / a twisting / an offset of the individual anode / cathode layers with respect to one another after the anode / cathode layers have been deposited on the electrode stack, and / or wherein the control unit is determined and configured to determine an offset of the individual anode / cathode layers with respect to one another with an image input of at least one third camera of at least one (vertical and / or transverse) edge of the electrode stack. In a variant of the device, the control unit is intended and configured to check an obtained image inclusion by corner / edge search to determine whether one or more of the anode / cathode layers of the electrode stack protrude or protrude from the remaining anode / cathode layers, and / or whether an accuracy in the stacking of the anode / cathode layers has been observed.In a variant of the device, the control unit is intended and configured to determine different dimensions from the image input of alternately stacked anode layers and cathode layers of the electrode stack with a stepped (high) edge in the z-direction side view, and to examine the stacked anode layers and cathode layers for their shape and / or dimensions. In a variant of the device, the control unit is intended and configured to examine, on the anode layers and cathode layers stacked on top of one another, the deviation with respect to the remaining anode layers or cathode layers of the electrode stack with which each individual layer protrudes / protrudes below. In a variant of the device, the control unit is intended and configured to examine an image registration with respect to the deviation in the z-direction (vertical axis) with which the different anode / cathode layers form steps in the electrode stack.In a variant of the device, the control unit is intended and configured to receive, from at least two third cameras, image entries which contain, from the side on corners, and / or edges thereof in the vertical axis (z-axis) of the electrode stack at the deposition location, in order to examine, at the anode layers and cathode layers stacked on top of one another, with which deviation in the x or y direction (transverse, longitudinal) with respect to the remaining anode layers or cathode layers of the electrode stack, each individual layer protrudes / protrudes below in the longitudinal and / or transverse direction of the layers; and / or to examine, with which deviation in the z direction (vertical axis) the different anode / cathode layers form steps in the electrode stack.In a variant of the device, the at least two cameras are aligned with a (high) edge of the electrode stack, and / or for illuminating the respective edge of the electrode stack (white) spotlights the desired position on the electrode stack.In a variant of the device, the control unit is intended and configured to receive, from at least four cameras, image pickups which contain the four corners of the electrode stack viewed from the side at the deposition location in order to determine a position of the uppermost deposited anode / cathode layer in relation to at least one underlying layer of the electrode stack by checking the position / a twisting / an offset of the individual anode / cathode layers with respect to one another by means of an image pickup from each of the four cameras after the deposition of the anode / cathode layers on the electrode stack.In a variant of the device, the control unit is intended and configured to take account of movements of the lifting device with the respective workpiece carrier along the high axis (z axis) and inaccuracies thereof by, prior to the beginning of the depositing of the anode / cathode layers to form the electrode stack, the x-, y-positions of the workpiece carrier at different z heights being captured by means of image input devices, the corresponding data being stored in a data memory for comparison with x-, y-positions of the workpiece carrier at different z heights during the depositing of the anode / cathode layers in order to check whether the anode / cathode layers have been deposited at the x-, y-position within the accuracy, which corresponds to the respective z position of the workpiece carrier on the lifting device, and / or for correcting the orientation in the rotational direction about the z axis (high axis) (in theta) when the anode / cathode layers are picked up and / or deposited.The above-described approaches and devices allow a significant reduction in the risk of short circuit of the module thus formed, which also leads to an increase in the overall quality and efficiency of the completed fuel or battery cell.Overall, the above-described apparatus and method allows accuracy of ±0.1 mm or more accurately at high stack throughput.Method aspects are presented above in device terms and vice versa. Both the method aspects and the device aspects serve to explain the arrangement and its operation.Brief Description of the FiguresFurther features, properties and advantages of the apparatuses and of the procedures can be taken from the following description in conjunction with the drawing. Possible modifications will become apparent to a person skilled in the art from the following description, in which reference is made to the accompanying drawings. In this regard, the figures schematically show the devices discussed herein and illustrate their operation. In the figures, identical or analogous parts are not individually provided with reference numerals in individual cases.The following are shown here: FIG. 1 shows a device for producing modules or precursors of modules in a schematic front view; FIG. 2 shows one of the two layer inverters of a device for producing modules or precursors of modules in a further variant in a schematic side view; FIG. 3 is a perspective side view of a layer reversing device with a stacking table on which a layer stack is located; FIGS. 4 aand 4 b show a plan view of the placement of a stack table on which a layer stack is located at the first and the second placement location with a configuration of the image pick-ups for the second inspection; FIGS. 5 aand 5 b show a plan view of the placement of a stack table on which a layer stack is located at the first and the second placement location with a configuration of the image pick-ups for the third inspection; FIG. 6 is a plan view of the placement of a stack table on which a layer stack is located at the first and the second placement location with a configuration of the image pick-ups for the second inspection; and FIG. 7 is a plan view of the placement of a stack table on which a layer stack is located at the first and the second placement location with a further configuration of the image pick-ups for the third inspection.Detailed Description of Variations of Devices and ProceduresFIG. 1 schematically illustrates an apparatus 100 for manufacturing modules or precursors of modules. Here, the apparatus 100 is exemplified by the manufacture of fuel or battery cells that contain sheet material and / or fluid.In the apparatus 100, a first conveyor 110 serves to convey individual anode layers AL to a first transfer point U 1 for transfer to a first layer inverter 150. A second conveyor 120 serves to convey individual cathode layers KL to a second transfer point U 2 for transfer to a second layer inverter 200.As illustrated in FIG. 1, the first conveyor 110 and the second conveyor 120 are disposed at the top of the apparatus 100 at the same level, adjacent, and spaced apart from each other. In this case, the first conveyor 110 and the second conveyor 120 are designed here as belt conveyors, which face the first and second layer turners 150, 200 with their respective underside 112, 122. Thus, the first conveyor 110 and the second conveyor 120 can convey the individual anode layers AL and the individual cathode layers KL on their underside 112, 122 to the first and the second transfer point U 1, U 2, respectively. In particular, the first conveyor 110 and the second conveyor 120 each have a controlled vacuum conveyor belt with suction openings 114, 124 in order to pick up the individual anode layers AL and the individual cathode layers KL by means of controlled supplied pneumatic vacuum p-and to hold them during the conveying to the first and the second transfer point U 1, U 2. By means of an optionally controlled supplied pneumatic overpressure p++, the individual anode layers AL or the individual cathode layers KL can be controlled and quickly delivered at the first or the second transfer point U 1, U 2 to the first or second layer inverter 150, 200. Alternatively, the pneumatic negative pressure p--of the first or second conveyor 110, 120 can be reduced or eliminated at the first or second transfer point U1, U2. The first conveyor 110 can take over the individual anode layers AL from a stack or a third conveyor (not shown), in particular a vacuum conveyor belt. The second conveyor 120 can take over the individual cathode layers KL from a stack or a fourth conveyor (not shown), in particular a vacuum conveyor belt.The first and the second layer reversing device 150, 200 each have four approximately rectangular planar pick-ups 156, 206 and a first drive 300 (see FIG. 2 ). With the pick-ups 156, 206, a respective individual anode or cathode layer AL, KL is picked up in a planar manner by the first or second conveyor 110, 120 at the respective first or second transfer point U 1, U 2. These pick-ups 156, 206 are mounted indirectly on a rotatably mounted shaft 160, 210 in a radially displaceable manner. This shaft 160, 210 rotates the respective pick-ups 156, 206 by means of the first drive 300 by a respective rotation angle RW-in this case 180°-to a respective first or second dispensing point A 1, A 2. The first drive 300 rotates the layer inverters 150, 200 as a whole. The first and the second layer inverter 150, 200 are thus configured with their respective multiple pick-ups for picking up the individual anode or cathode layers AL, KL when the pick-ups successively rotate past the respective transfer point U 1, U 2 and the respective delivery point A 1, A 2 continuously or in a clocked manner, and in the process pick up or deliver the respective individual anode or cathode layer AL, KL. The first and the second layer turners 150, 200 rotate by means of their respective first drive 300 in the clockwise or counterclockwise direction in such a way that the individual anode or cathode layers AL, KL pass from their transfer point U 1, U 2 to their delivery point A 1, A 2, while avoiding the space R between the first and the second layer turners 150, 200.It can be seen that the first and the second layer reversing device 150, 200 have essentially a matching structure, a matching function and / or a matching dimension.An endless separator belt, not shown in detail, is guided from above between the two conveyors 110, 120 into and through the space R and exits at the lower end of the space R from a nip between two rotatably mounted rollers. The separator strip is folded in a Z-shape on the stack table and the anode and cathode layers are separated from one another by the separator.The first and the second layer inverter 150, 200 have (see FIG. 1 ) for the pick-ups 156, 206 as a second drive 350 an arrangement of linear drives 351 arranged on rotary rings, of which in each case one linear drive 351 is coupled in a driven manner to one of the pick-ups 156, 206 in order to radially retract and / or extend the pick-ups of the respective layer inverter 150, 200.In a further variant, the first and the second layer reversing device 150, 200 each have a second drive 350 (see FIG. 2 ) for the pick-ups 156, 206. This second drive 350 serves to retract the respective pick-up 156, 206 radially when-after the respective layer has been deposited on the stacking table 400-the pick-up of the other layer reversing device approaches on its way to its pick-up point U1, U2 in the space between the two layer reversing devices. The second drive 350 rotates the tube, the associated swivel ring and the receivers 156, 206 about the center of rotation DZ. Due to the coupling to an eccentric explained below, the receivers 156, 206 are moved radially. The first drive 300 is a controlled servo motor that rotates the layer inverter as a whole to turn the pickup around a rotation center of the layer inverter. In the variant illustrated in FIG. 2, the second drive 350 is a servo-motor which is to be controlled independently by the first rotary drive 300 and is coupled in drive fashion to the inner shaft 160, 210 designed as an eccentric shaft. This eccentric shaft is provided with eccentrics 372, 374 for each of the receivers for radially retracting and extending the receivers 156, 206 of the respective layer inverter 150, 200. For this purpose, each eccentric 372, 374 is surrounded by a needle bearing which carries on the outside a ring 376, 378 which is articulated on the respective receiver 156, 206. The respective eccentric 372, 374 causes, upon a rotation of the shaft 160, 210, the receivers 156, 206 guided in radially oriented linear guides 380, 382 in each case to move outwards or inwards. In particular, a radial retraction of the pick-ups of the first and / or of the second layer inverter takes place when the pick-up approaches a pick-up of the other layer inverter on the path from its delivery point to its delivery point or from its delivery point to its delivery point.The second drive 350 rotates the respective inner shaft 160, 210 and causes the receivers to extend and retract radially. In particular, the second drive 350 also serves to cause the first and second layer inverters to move the respective receivers out radially when the receivers approach the respective first and second transfer points U1, U2 and the first and second transfer points A1, A2. Overall, in this variant, the pick-ups of the two layer inverters each move approximately on an approximated, vertical ellipse, the main axes of which extend from the center of the respective transfer point to the center of the respective delivery point, and the minor axes of which do not touch one another. In FIG. 1, this ellipse E is illustrated in dash-dot lines at the second layer turn 200. This movement need not be symmetrical, since the receiver located away from the space R is moved radially further out than the receiver located in the space R.The first drive 300 and the second drive 350 are combined via a combined angular and axial gear 390 and set in rotation independently of one another the inner shaft 160, 210 or all receivers of a layer reversing device as a whole via a connecting element, for example a tube 352. As illustrated in FIG. 2, the tube 352 and the shaft coupled to the first drive 300 have collinear axes of rotation.A stacking table 400 for receiving the individual anode and cathode layers AL, KL at the respective first and second delivery point A 1, A 2 is provided with a drive 410. This drive 410 moves the stacking table 400 back and forth between the first and the second delivery point A 1, A 2 in a controlled manner along the x-axis, so that the stacking table 400 is aligned precisely in position with the individual anode or cathode layer AL, KL to be deposited thereon. In Figure 1, the stacking table is shown in solid lines in its left-hand aligned position under the ply turn 150 and in short dash lines in its right-hand aligned position under the ply turn 200.The first and the second layer reversing device 150, 200 each discharge a single anode and cathode layer AL, KL from their pick-up 156, 206-in the 6 o'clock position in FIG. 1-to the stacking table 400 at the first and the second discharge point A 1, A 2 when the pick-up 156, 206 is located at the first and the second discharge point A 1, A 2.For this purpose, in the variant of the apparatus 100 illustrated here, the first and the second transfer point U 1, U 2 each have a first center (approximately above the center of the receivers located in the 12 o'clock position between the receiver and the conveyor), and the first and the second transfer point A 1, A 2 each have a second center (approximately below the center of the receivers located in the 6 o'clock position between the receiver and the stacking table). These respective first and second centers lie on an imaginary straight line which intersects a respective rotation center DZ of the first layer inverter 150 and of the second layer inverter 200, respectively. The first and the second layer turner turn only individual ones of the anode layers AL and only individual ones of the cathode layers KL towards the first and the second delivery point A 1, A 2, respectively.In the arrangement with the eccentric drive, the first drive of a layer inverter and the second drive of the same layer inverter can rotate continuously in the same direction or else temporarily in the opposite direction. As a result, the rotational movement of the layer reversing device as a whole can be superimposed with the radial inward / outward movement of its pick-ups in such a way that a particularly small distance between the two layer reversing devices, and thus a particularly short path between the two delivery points, is possible. Moreover, the two layer inverters (in both variants of FIGS. 1 and 2 ) can be set in rotation by their respective first drives in such a way that the pick-up / take-up / take-up of one layer inverter rotates exactly in opposite phase to the pick-up / take-up / take-up / take-up / take-up of the other layer inverter. This means that in the case of one pick-up per layer inverter, one pick-up of one layer inverter is located near the transfer point, while one pick-up of the other layer inverter is located near the transfer point. In the case of four receivers per layer inverter, one receiver of one layer inverter leads an inverter of the other layer inverter by about 45°.The stacking table 400 has a tray 420 for the individual anode and cathode layers AL, KL and an adjusting device 430 with a corresponding rotary drive about the z-axis, which move the tray 420 along the axes and about the z-axis. Thus, the stacking table 400 and its tray 420, more precisely its center, are to be aligned precisely with the first and second delivery points A1, A2 and the pick-up in the 6 o'clock position.The stacking table 400 has first and second clamping fingers 442, 444. In a variant, two clamping fingers are provided on each of two mutually opposite sides. The clamping fingers move in the y direction perpendicular to the plane of rotation of the pick-ups. These two clamping fingers 442, 444 engage from both (transverse or longitudinal) sides along the x or y direction laterally over the electrode stack formed from anode and cathode layers AL, KL and controllably engage or disengage the respective uppermost of the anode and cathode layers AL, KL in order to urge the respective uppermost of the anode and cathode layers AL, KL against the electrode stack ES on the tray 420. For this purpose, corresponding linear drives 446, 448 are provided in the z direction and in the x direction or y direction depending on the arrangement of the clamping fingers 442, 444, which move the first and second clamping fingers 442, 444 in a controlled manner relative to the base plate 450 of the stacking table 400 and to the tray 420 thereof. In one variant, the stacking table 400 is supported on a rigid plate which has a recess. The base plate 450 can be moved relative to the rigid plate only in the x direction along two linear guides. A Y plate is located on the base plate 450, which can be moved in the y direction relative to the base plate 450. The Y-plate carries an actuator plate. The shelf 420 is located on the actuator plate. The actuator plate is rotatable together with the shelf 420 about the z-axis and thus also the clamping fingers and their actuators.An x- or y-actuator is located on the actuator plate for each clamping finger, depending on the direction of movement and arrangement of the clamping fingers, in order to be able to position a single clamping finger in the y-direction. The z-actuator of each clamping finger is disposed on a separate plate disposed on the Y-plate and adjacent the tray 420. The y-actuator thus displaces the separate plate and thus the respective clamping finger 442, 444 together with its z-actuator.The clamping fingers 442, 444 also serve to clamp the endless separator belt against the tray 420 or the stack formed up to now during the movement of the stack table between the delivery points A 1, A 2, so that anode and cathode layers AL, KL deposited on the tray 420 are always separated by the electrically insulating separator.When the Y plate is displaced in the y direction, the actuator plate is also displaced together with the clamping fingers in the y direction. The tray 420 is positionable in the z direction by a z drive which may be located just below the tray and which has freedom of movement in the X direction in the central recess of the rigid plate.The first and second layer inverters 150, 200 are configured to receive and hold the individual anode layers AL and the individual cathode layers KL by means of controlled pneumatic vacuum p--during the inverter to the first and second delivery points A 1, A 2, respectively. In addition, in the variant of the device 100 shown here, the first and the second layer inverter 150, 200 are configured to discharge the individual anode layers AL and the individual cathode layers KL in the first and the second discharge point by means of a short blow impact, by means of controlled pneumatic overpressure p++, in order to stack the layers AL, KL on the deposit 420 to form the electrode stack ES.For this purpose, it is illustrated in FIG. 2 that the first and the second layer inverter 150, 200 each have a rotatable over / under pressure distribution 650, which is arranged around the inner shaft 160, 210 in order to feed the pick-ups with the controlled pneumatic negative pressure p- and / or positive pressure p++. In this case, two concentric rings 652, 654 are provided rotatably, surrounding one another in a fluid-tight manner, in which an over / under pressure transfer 656 is realized for each of the receivers. For each receiver 156, 206, a fluid line reaches from the over / under pressure transfer 656 into the inner shaft 160, 210 and from there to a connection for a radially flexible line 656 to the respective receiver 156, 206. The flexible conduit 656 is connected to a plurality of apertures in the surface of the receivers remote from the center of rotation.Alternatively, each of these apertures is associated with a resilient nozzle which slightly (for example less than 3 mm) projects above the surface of the receiver and is connected to the flexible conduit 656. The anode layers AL and cathode layers KL can thus be picked up reliably and gently and can be dispensed again with high precision in their alignment on the support 420. The adjusting device 430 lowers the deposition 420 during stacking in a controlled manner by a distance corresponding to a thickness of an individual anode layer AL or an individual cathode layer KL after each deposition of the individual anode layers AL and the individual cathode layers KL. This ensures a very short, defined free path between the discharge from the pick-up 156, 206 and the impact on the electrode stack ES.The first to third inspection of the sheet material integrated in the above variants, for example in the production of fuel or battery cells, is illustrated below.The first inspection device has a first layer conveyor 150 (on the left in FIG. 1 ) with four pick-ups 156 and a first drive 300 in order to pick up a respective individual anode or cathode layer AL, KL by means of the at least one pick-up 156 from a first transfer point U 1 and to bring it to a first discharge point A 1. The first layer inverter 150 discharges a single anode or cathode layer AL, KL from its pick-up 156 to the stacking table 400, more precisely to its deposit 420, in each case at the first discharge point A 1 when the respective at least one pick-up 156 is located at the first discharge point A 1. The drive 410 aligns the pick-up 156 and the stacking table 400 relative to one another depending on signaling based on processing of the first and / or second image registration. A first image recorder K1 is aligned with a first region E1 of the first layer inverter 150 between the first transfer point U1 and the first delivery point A1 and carries out a first image registration when the recorder 156 of the first layer inverter 150 with the individual anode or cathode layer AL, KL passes the first image recorder K1. A second image recorder K2 is aligned with a second region E2 of the first layer inverter 150 between the first transfer point U2 and the first delivery point A2 and carries out a second image registration when the recorder 156 of the first layer inverter 150 with the individual anode or cathode layer AL, KL passes the image recorder K2. The second region E 2 may be different from the first region E 1. The stack table 400 receives the respective individual anode layer AL at the first delivery point A 1 and the respective individual cathode layer KL at the second delivery point A 2 to form a layer stack.In the variant shown, the first layer conveyor 150 has a layer inverter 156 in order to pick up a respective individual anode or cathode layer from the first transfer point U 1 by means of the at least one pick-up 156 and to rotate a respective angle of rotation-here approximately 180°-to the first transfer point A 1.In a variant not shown in any more detail here, the first layer conveyor 150 has a layer gripper which receives a respective individual anode or cathode layer from the first transfer point U 1 by means of a pick-up, for example in the form of a suction or gripping tool, and brings it to the first discharge point A 1.Analogously to the first layer conveyor 150, a second layer conveyor 200 (on the right in FIG. 1 ) is provided and configured to receive a single cathode or anode layer KL, AL and to bring it to a second delivery point A 2. A first image pickup K1' between the second transfer point U2 and the second discharge point A2 is aligned with a first area E1' of the second sheet conveyor 200 and performs a first image registration when the second sheet conveyor 200 passes the first image pickup K1'. A second image pickup K2' is aligned with a second region E2' of the second layer conveyor between the second transfer point U2 and the second delivery point A2 and carries out a second image registration when the second layer conveyor passes the second image pickup K2'.In the variant shown, the second layer conveyor 200 has a layer inverter 206 which receives a respective individual anode or cathode layer from the second transfer point U 2 by means of the at least one receiver 206 and rotates a respective angle of rotation-in this case 180°-to a second discharge point A 2.In a variant not shown in any more detail here, the second layer conveyor 200 has a layer gripper which is provided and configured to pick up a respective individual anode or cathode layer from the second transfer point U 2 by means of a pick-up, for example in the form of a suction or gripping tool, and to bring it to the second discharge point A 2.A drive 410 is associated with the stacking table 400, which drives the stacking table 400 back and forth between the first and the second delivery point A 1, A 2. The first and second sheet conveyors deliver a single anode or cathode sheet AL, KL to the stacking table 400 at the first and second delivery points A1, A2, respectively, when the stacking table is located at the first and second delivery points A1, A2. A drive aligns the respective layer conveyor and / or the respective at least one layer inverter 156, 206 to the stacking table 400 as a function of signaling based on processing of the first and the second image registration.The first region E 1 and the second region E 2 of the pick-ups of the two layer inverters 150, 200 are corner regions of the pick-up of the layer inverters 150, 200 lying diagonally with respect to one another here. The first region E 1 and the second region E 2 of the pick-ups of the two layer inverters 150, 200 are provided and configured for picking up a first corner and a second corner, respectively, of the individual anode or cathode layer AL, KL. Consequently, the first and second imagers K1, K2, K1', K2' are arranged diagonally with respect to one another and are aligned with the first region E1 and the second region E2 of the imagers of the two layer inverters 150, 200 when these pass the first and second imagers K1, K2, K1', K2'. The first and the second image pick-ups K 1, K 2, K 1', K 2' are arranged here between the two transfer points U 1, U 2 and the two delivery points A 1, A 2 in such a way that they are aligned on the first and the second region E 1, E 2 of the respective pick-ups 156, 206 at the time of the first and / or second image acquisition at an angle of approximately 90° between the camera axis and the anode or cathode in the inspection position for the first and the second image pick-ups K 1, K 2, K 1', K 2'.The first and / or the second image pick-up K 1, K 2, K 1', K 2' can be adjusted here for focusing along their optical axes. In other variants, they can instead or additionally also be moved during operation. White light sources assigned to the first and second image pick-ups K 1, K 2, K 1', K 2' lighten the anode / cathode layer for image registration. In further variants, one or more optically active elements are assigned to the first or the second image recorder K 1, K 2, K 1', K 2', in order to record the position and / or orientation of the anode / cathode layer at one or more locations or regions before or upon its arrival at the delivery point or on the way to the delivery point. Optically active elements can be a lens or lens arrangement, a mirror or mirror arrangement, a prism or prism arrangement, a light guide arrangement, a surface light, a coaxial ring light, a dark field light, etc., or combinations thereof.The control unit ECU determines correction values from the position and / or orientation of the anode / cathode layer AL, KL before it is picked up by the stack table 400, the position and / or orientation of the stack table 400, and / or the position and / or orientation of the picked-up individual anode / cathode layer AL, KL relative to the stack table 400 during a turning of the anode / cathode layer AL, KL to the stack table 400. The control unit ECU takes these correction values into account in adjusting commands to the layer inverter, the pick-up and / or the stacking table when aligning the stacking table 400 with the transported anode / cathode layer relative to the deposition location A 1, A 2. The control unit 400 takes these correction values into account in particular for the alignment and the location of the stack table when recording the anode / cathode layer in actuating commands to the layer inverter, the pick-up and / or the stack table in such a way that the stack table records the respective anode / cathode layer in a central zero position and / or aligned with the electrode stack located at the delivery point.By checking the position of the incoming anode / cathode layer AL, KL in the image inlets directly in front of the respective delivery point A 1, A 2, the control unit determines the orientation and the location of the stack table 400 during or before the pick-up of the anode / cathode layer AL, KL.An inspection method also serves for the inspection, comprising the steps: picking up an anode / cathode layer AL, KL by means of a pick-up 156 of a layer reversing device 150, 200 from a transfer point U1, U2; conveying the pick-up 156 of the layer reversing device 150, 200 from the transfer point to a transfer point A1, A2; detecting position and / or orientation in x, y, z, and / or theta of the anode / cathode layer AL, KL on the pick-up 156 of the layer inverter 150, 200 by means of a first image pick-up K1 between the transfer point U1 and the delivery point A1, wherein the first image pick-up K1 is aligned with a first region E1 of the layer inverter 150 and is provided and configured for a first image registration when the pick-up of the layer inverter passes the first image pick-up K1; detecting position and / or orientation in x, y, z, and / or theta of the anode / cathode layer AL, KL on the at least one pick-up 156 of the layer inverter 150, 200 by means of a second image pick-up K2 between the transfer point U1, U2 and the delivery point A1, wherein the second image pick-up K2 is aligned with a second region E2 of the layer inverter 150 and is provided and configured to form a second image entry when the pick-up of the layer inverter passes the second image pick-up K2; aligning the pick-up 156 and the stacking table 400, more precisely its deposit 420, relative to one another as a function of signaling based on processing of the first and / or second image entry; and discharging the anode or cathode sheet AL, KL from the picker 156 at the discharge location A1, A2 onto the stack table 400 to form a sheet stack when the respective picker 156 is at the discharge location A1, A2.The first and the second image pick-up K 1, K 2 record, in a vertical plan view of the anode / cathode layer AL, KL, their position and / or orientation in x, y, z and / or theta when the pick-up of the layer reversing device passes the respective image pick-up K 1, K 2. A light source L 1, L 2 assigned to the first and / or the second image sensor K 1, K 2 illuminates the anode / cathode layer AL, KL for image introduction through the first and the second image sensor K 1, K 2. In a variant, not illustrated, the first and the second image pick-up K 1, K 2 completely record the anode / cathode position AL, KL with an image input in order to record their position and / or orientation in x, y, z, and / or theta. In a further variant, the first and / or the second image recorder K 1, K 2 record, with a single image capture, a region, at least one corner region, two diagonal corner regions, or at least one corner region and at least one portion of an edge of the anode / cathode layer AL, KL relative to a respective defined image recorder zero point in order to record the position and / or orientation in x, y, z, and / or theta of the anode / cathode layer AL, KL. The first or the second image pickup K 1, K 2 can be designed as matrix cameras or as line cameras which record the position and / or orientation in x, y, z and / or theta of the anode / cathode layer AL, KL before or upon their arrival at the delivery point A 1 or on the path to that of the delivery point A 1.The correction values are determined from the position and / or orientation in x, y, z, and / or theta of the anode / cathode layer AL, KL after being picked up by the at least one pick-up of the layer inverter, the position and / or orientation in x, y, z, and / or theta of the stack table 400, and / or the position and / or orientation in x, y, z, and / or theta of the picked-up individual anode / cathode layer AL, KL during an inverter of the anode / cathode layer AL, KL to the stack table 400. These correction values are taken into account when aligning in x, y, z and / or theta the stacking table 400 at the delivery point A1, A2 relative to the pick-up of the layer inverter with the transported anode / cathode layer AL, KL at the delivery point A1, A2. These correction values are taken into account in x, y, z and / or theta when aligning the stack table 400 or the pick-up of the layer inverter in such a way that the anode / cathode layer AL, KL is picked up by the stack table 400 in a central zero position and / or aligned.In the second inspection apparatus 100, the first sheet conveyor 150 receives a single anode or cathode sheet AL, KL from a first transfer location U 1 and carries it to a first discharge location A 1. A stack table 400, more precisely its deposit 420, receives the individual anode or cathode layer AL, KL at the first delivery point A 1 in order to form a layer stack. The first layer conveyor 150 discharges a single anode or cathode layer AL, KL to the stacking table 400 at the first discharge point A 1 when the stacking table is located at the first discharge point A 1. A third image recorder K 3, K 3' is directed at at least one region E 3, E 3' comprising an upper edge OK of a layer stack located on the stack table 400 in a side view. This region E 3, E 3' comprises a terminal tab T of an anode or cathode layer AL, KL located at the top of the layer stack. The third imager K3, K3' performs a third image registration after the anode and cathode sheets AL, KL on the sheet stack are deposited on the stack table 400. A controller ECU indicates the interoperability of the layer stack as a function of signaling based on processing of the third image acquisition.The layer conveyor here has a layer inverter which receives individual anode or cathode layers from the first transfer point U 1 by means of one of four receivers 156 and rotates them by a respective angle of rotation-here 180°-to the first discharge point A 1.In a variant which is not illustrated in any more detail, the layer conveyor has a layer gripper which receives a respective individual anode or cathode layer from the first transfer point U 1 and brings it to the first discharge point A 1 by means of a pick-up, for example in the form of a suction or gripping tool.A second layer conveyor analogous to the first layer conveyor receives a single cathode or anode layer KL, AL and delivers it to a second delivery point A2. A drive 410 is associated with the stacking table 400, which drives the stacking table 400 back and forth between the first and the second delivery point A 1, A 2. The first and second sheet conveyors deliver a single anode or cathode sheet AL, KL to the stacking table 400 at the first and second delivery points A1, A2, respectively, when the stacking table is located at the first and second delivery points A1, A2. At least one drive serves to align the respective layer conveyor and / or the respective at least one layer inverter 156, 206 or layer gripper relative to the stacking table 400 as a function of signaling based on processing of the first and / or second image feeding in a control ECU.The second layer conveyor also has a layer inverter and likewise receives a single anode or cathode layer by means of the pick-up 206 from the second transfer point U2 and rotates it by a rotation angle-in this case 180°-to a second discharge point A2.In a variant which is not shown, the second layer conveyor has a layer gripper which receives a respective individual anode or cathode layer from the second transfer point U 2 and brings it to the second discharge point A 2 by means of a pick-up, for example in the form of a suction or gripping tool.A first third region E3 and a second third region E3'-see FIG. 4a-of the layer stack each comprise-in side view-a terminal tab of the respectively uppermost anode or cathode layer AL, KL on the stack table 400 at the first and the second delivery point A1, A2, respectively. One or two third imagers K 3, K 3 a, K 3', K 3 a' are arranged on a first side, for example the left side in FIG. 1, of the inspection device 100 or the tray 420, respectively, and one or two third imagers K 3, K 3 a, K 3', K 3 a' are arranged on a second side, for example the right side in FIG. 1, of the inspection device 100 opposite the first side. Two third imagers K 3, K 3 a, K 3', K 3 a' to one side of the inspection device 100 and the tray 420, respectively, are spaced apart from each other with respect to a Y direction. In one variant, one or more third image pick-ups K 3, K 3 a, K 3', K 3 a' are arranged in a fixed position relative to the stacking table 400 moving back and forth between the two delivery points A 1, A 2. This is illustrated in FIG. 4 a. In variants which are not shown in more detail, of the four stationary third image receivers K3, K3a', K3a, K3', only two diagonally arranged third image receivers are provided, that is to say the third image receivers K3, K3a' or the third image receivers K3a, K3' in FIG. 4a. Alternatively, in variants, not shown in detail, of the four stationary third image pickups K3, K3a', K3a, K3', only two third image pickups arranged on one side of the stacking table 400, i.e. the third image pickups K3, K3a or the third image pickups K3a', K3', are provided in FIG. 4a. In one variant, an optical axis of the one third image recorder or of each of the plurality of image recorders is oriented horizontally or has a maximum deviation of + / - 10° from a horizontal.As a further variant in this respect, FIG. 6 shows a plan view of the storage area 420 of a stack table on which a layer stack is located at the first and the second storage location with a configuration of the image pick-ups for the second inspection.In this case, the third image pick-ups K3a, K3' are illustrated by way of example, which pick-ups, with counter light or transmitted light from light sources WL, each record the first and second third regions E3, E3' - in the side view from the outside. Thus, a terminal tab of the respective uppermost anode or cathode layer AL, KL on the stack table 400 is inspected at the first and the second delivery point A 1, A 2.If the space conditions permit this, in other variants one or more third image pick-ups K3, K3a, K3', K3a' are firmly connected to the stacking table 400-see FIG. 4b-and can be moved with the latter between the two depositing points A1, A2. In variants which are not shown in detail, of the four third image receivers K3, K3a', K3a, K3' which can be moved with the stacking table, only two diagonally arranged third image receivers are provided, that is to say the third image receivers K3, K3a' or the third image receivers K3a, K3' in FIG. 4b. Alternatively, in variants, not shown in detail, of the four third image receivers K3, K3a', K3a, K3' that can be moved with the stacking table, only two third image receivers are provided that are arranged on one side of the stacking table 400, i.e., in FIG. 4b, the third image receivers K3, K3a that can be moved with the stacking table or the third image receivers K3a', K3' that can be moved with the stacking table.The third / n image pick-up / s K3, K3a, K3', K3a' can be adjusted along their optical axis for focusing on the areas E3, E3'. A light source L3 - see FIG. 3 - assigned to the third image pick-up(s) K3, K3a, K3', K3a' in each case illuminates the anode / cathode layer on the layer stack for image introduction by the third image pick-up / image pick-ups. Here, the light source L 3 is coaxial ring illumination. The coaxial ring illumination is arranged on the side of the third image pickup K3, directly at the respective third image pickup K3, K3a, K3', K3a', this side of the position of the connection lug T on the stack table 400, and is configured to take the connection lug T into the light beam path. Thus, by processing the third image feed, a vertical lifting of the connection lug T can be detected in that the uppermost edge of the connection lug T is not horizontally oriented in the image feed and / or causes a disturbing contour.A second inspection method in the production of modules or precursors of modules comprises the steps of: receiving an anode / cathode layer AL, KL at the first transfer point U 1 and bringing the anode or cathode layer AL, KL from the first transfer point U 1 to a first discharge point A 1; discharging the respective individual anode or cathode layer AL, KL at the discharge point A 1, A 2 onto a stack table 400 to form a layer stack; directing a third image recorder K 3, K 3' onto an area E 3 comprising an upper edge OK of a layer stack located on the stack table 400 in a side view, wherein the area comprises a connection flag T of an anode or cathode layer AL, KL located at the top of the layer stack; and wherein a third image registration is carried out by means of the third image recorder K 3, K 3' after the anode or cathode layer AL, KL is deposited on the stack table 400; and indicating an interoperability of the layer stack depending on a signaling based on a processing of the third image registration.In the variant shown, the coaxial ring illumination is arranged on the side of the third image pickup, this side of the position of the connection lug T on the stacking table 400, and the third image pickup K 3 is set up, so that the connection lug T is taken into the light beam path. Finally, the third image registration is performed, which is processed in the ECU in order to detect lifting of the connection flag T by means of processing of the third image registration, in that the uppermost edge of the connection flag T is not horizontally oriented in the third image registration and / or causes a disturbing contour.In a third sheet material inspection apparatus 100, particularly for manufacturing fuel or battery cells, a first sheet conveyor 150 receives a single anode or cathode sheet AL, KL and delivers it to a first discharge location A1. A stack table 400 receives the anode or cathode layer AL, KL at the first delivery point A 1 to form a layer stack. The first sheet conveyor 150 discharges the anode or cathode sheet AL, KL to the stacking table 400 at the first discharge location A 1. A fourth image recorder K 4 is aligned with a fourth region E 4 of the layer stack of anode and cathode layers AL, KL in a planar side view of the layer stack and carries out a fourth image registration after the anode or cathode layer AL, KL is deposited on the layer stack on the stack table 400, wherein the fourth region E 4 comprises a corner of an anode or cathode layer AL, KL located uppermost on the layer stack and / or a top edge HK of the layer stack. It is also possible to see not only the uppermost stacked layer, but also one or more further downstream incorrectly positioned layers of the overall stack. Thus, outliers that have shifted due to changes in the processes can be found. In the variant shown, a fifth image recorder K 5 is aligned with a fifth region E 5 of the layer stack of anode and cathode layers AL, KL in a planar side view of the layer stack and carries out a fifth image registration after the anode or cathode layer AL, KL is deposited on the layer stack on the stack table 400, wherein the fifth region E 5 comprises a corner of an anode or cathode layer AL, KL located at the top of the layer stack (or below, see above) and / or a top edge HK of the layer stack. The regions E4 and E5 are disjunct here. In particular, the fourth region E 4 or the fifth region E 5 of the anode or cathode layer AL, KL in the layer surface comprise regions of the layer stack of anode and cathode layers AL, KL lying adjacent or diagonally to one another in a respective side view of the layer stack.The layer conveyor comprises a layer inverter 156 for receiving a single anode or cathode layer from the first transfer point U 1 by means of at least one receiver 156 and for rotating a respective rotation angle-in this case 180°-to the first discharge point A 1.The fourth image pickup K4 and the fifth image pickup K5 are adjustable for focusing along their optical axis. A light source assigned to the fourth image recorder K 4 and the fifth image recorder K 5 respectively illuminates the anode / cathode layer for a fourth image recorder or a fifth image recorder through the fourth image recorder K 4 or fifth image recorder K 5. At least one optically active element is assigned to the fourth image sensor K4 or fifth image sensor K5, respectively, which makes the corner E4 or E5 of the anode or cathode layer AL, KL located at the top on the layer stack and the respective top edge HK of the layer stack recognizable in the fourth image gate or the fifth image gate after the anode or cathode layer AL, KL is deposited on the layer stack. The at least one optically active element is here a coaxial ring illumination. The coaxial ring illumination is located on the side of the fourth image sensor K4 or of the fifth image sensor K5, this side of the position of the corner of the anode or cathode layer AL, KL located at the top (or further below, see above) on the layer stack and of the respective top edge HK of the layer stack. Together with the respective image pick-up, it takes the corner and / or the top edge HK into the light beam path. Thus, by processing the fourth image feed or the fifth image feed, lifting, displacement or rotation about the vertical axis of the anode or cathode layer AL, KL can be detected, in that the corner and / or the vertical edge HK causes a disturbing contour in the image feed.A first fourth region E4 and a second fourth region E4' of the layer stack each comprise a corner of the anode or cathode layer AL, KL located at the top of the layer stack and a top edge HK of the layer stack on the stack table 400 when said stack is located at the first and the second delivery point A1, A2, respectively.In a variant, a first fourth image recorder K4 and a first fifth image recorder K5 are arranged on a first side of the inspection device 100 (on the left in FIG. 5a), and a second fourth image recorder K4' and a second fifth image recorder K5' are arranged on a second side of the inspection device 100 opposite the first side (on the right in FIG. 5a). In FIG. 5 a, these plurality of fourth and fifth image pickups are arranged in a fixed position relative to the movable stacking table 400, more precisely its support 420. In FIG. 5 b, these plurality of fourth and fifth image pickups are connected to the stacking table 400 in order to be movable therewith.In order to realize a compact overall arrangement of the inspection device that is low in vibration for the inspection, in one variant the first and / or the second image pickup K 1, K 2, optionally additionally also the first fourth image pickup K 4 and / or the first fifth image pickup K 5, are arranged on a supporting frame which extends parallel to the pickup 156 when the pickup 156 passes the first and / or second image pickup K 1, K 2. In a further embodiment, the supporting frame can be L-shaped (horizontally disposed L) and can encompass the layer inverter 150 in an L-shaped manner, such that a side of the layer inverter 150 facing away from the first drive 300 (see FIG. 2 ) is rotatably accommodated on the supporting frame. Such a supporting frame can likewise be assigned to the second layer inverter 200 for the same purpose in order to receive the image pickups assigned to the second layer inverter 200.In variants which are not shown in more detail, of the four fourth and fifth image receivers K4, K4'K5, K5', only two diagonally arranged image receivers are provided, that is to say the image receivers K4, K5' or the image receivers K4', K5 in FIG. 5a or FIG. 5b. Alternatively, in variants, not shown in detail, of the four fourth and fifth image receivers K 4, K 4', K 5, K 5' that can be moved with the stacking table, only two image receivers arranged on one side of the stacking table 400, i.e., in FIG. 5 b, the image receivers K 4, K 5 that can be moved with the stacking table 400 or the image receivers K 4', K 5' that can be moved with the stacking table, are provided.As a further variant in this respect, FIG. 7 shows a plan view of the placement of a stack table on which a layer stack is located at the first and the second placement location with a configuration of the image pick-ups for the third inspection. In this case, the fourth or fifth image recorder K 4, K 5, K 4', K 5' is exemplarily oriented at an angle.beta. of about ±5° to about ±5° to a longitudinal or transverse edge of the anode or cathode layer AL, KL located at the top on the layer stack, for example about ±13°. Thus, interference of the loop- or S-shaped endless separator (not illustrated) is avoided. In this case, the optical axis of the fourth or fifth image recorder K4, K5, K4', K5' at the first or second delivery point A1, A2 can be inclined at the angle.beta., as viewed from above, selectively to the left or right of the (notionally) extended transverse or longitudinal edge of the anode or cathode layer AL, KL located at the top on the layer stack. This is illustrated with the imagers shown in dashed lines in FIG. 7. Thus, a corner region of the respectively uppermost anode or cathode layer AL, KL on the stack table 400 is inspected at the first and the second delivery point A 1, A 2. A third inspection method comprises the steps of: picking up an anode / cathode layer AL, KL by means of at least one pick-up 156, 206 of a layer inverter 150, 200 from a transfer point U 1, U 2; discharging the respective individual anode or cathode layer AL, KL from the respective at least one pick-up 156 at a discharge point A 1, A 2 onto a stack table 400 for forming a layer stack when the respective at least one pick-up 156, 206 is located at the discharge point A 1, A 2; directing a fourth image recorder K4 onto a fourth region E4 of the layer stack of anode and cathode layers AL, KL in a planar side view of the layer stack, wherein the fourth region E4 comprises a corner of an anode or cathode layer AL, KL located uppermost on the layer stack and / or a top edge HK of the layer stack; and carrying out a fourth image registration after the anode or cathode layer AL, KL has been deposited on the layer stack on the stack table 400; and / or directing a fifth image recorder K 5 onto a fifth region E 5 of the layer stack of anode and cathode layers AL, KL in a planar side view of the layer stack, wherein the fifth region E 5 comprises a corner of an anode or cathode layer AL, KL located uppermost on the layer stack and / or a top edge HK of the layer stack; and carrying out a fifth image registration after the anode or cathode layer AL, KL has been deposited on the layer stack on the stack table 400. In this case, the fourth region E 4 or the fifth region E 5 of the anode or cathode layer AL, KL comprise in the layer surface adjacent (for example lying on the same edge of the layer) or diagonally mutually lying regions of the layer stack of anode and cathode layers AL, KL in a respective side view of the layer stack; and indicating non-usability of the layer stack depending on signaling based on processing of the fourth or the fifth image input.The fourth and the fifth image pickup K 4, K 5 can be adjusted for focusing along its optical axis. The fourth or the fifth region E 4, E 5 for the fourth or the fifth image pick-up is illuminated by the respective image pick-up K 4, K 5 K 4', K 5' by means of a light source assigned to the fourth or the fifth image pick-up. The fourth or the fifth image pickup is assigned an optically active element, here in the form of coaxial ring illumination, in order to make recognizable the corner of the anode or cathode layer AL, KL located on the top of the layer stack and / or the top edge HK of the layer stack in the fourth or the fifth image pickup after the anode or cathode layer AL, KL is deposited on the layer stack. The coaxial ring illumination is arranged as incident light on the side of the fourth or the fifth image recorder, this side of the position of the corner of the anode or cathode layer located uppermost on the layer stack or of the upper edge of the layer stack on the stack table. For this purpose, the incident light illumination is set up in order to take the corner and the top edge HK of the layer stack into the light beam path. By processing the fourth or the fifth image input, this allows the anode or cathode layer AL, KL located on the top of the layer stack to be recognized at least partially by lifting, displacing or rotating, in which the top corner and / or the top edge HK causes a disturbing contour.The variants of handling and inspection described above, their construction and operating aspects, and the variants of the procedure serve merely for better understanding of the structure, the mode of operation and the properties; they do not limit the disclosure, for example, to the exemplary embodiments. The figures are partially schematic. Essential properties and effects are in some cases shown in a clearly enlarged manner in order to clarify the functions, principles of action, technical configurations and features. In this case, each mode of operation, each principle, each technical configuration and each feature which is / are disclosed in the figures or in the text can be freely and arbitrarily combined with all claims, each feature in the text and in the other figures, other modes of operation, principles, technical configurations and features which are contained in this disclosure or result therefrom, with the result that all conceivable combinations are to be associated with the described procedure. Combinations between all individual embodiments in the text, i.e. in each section of the description, in the claims and also combinations between different variants in the text, in the claims and in the figures, are also included here. The claims also do not limit the disclosure and thus the possible combinations of all features shown with one another. All disclosed features are explicitly also disclosed individually and in combination with all other features here.

Claims

An inspection device (100) for sheet material for manufacturing fuel or battery cells, wherein - a first sheet conveyor (150) is provided and configured to receive a respective single anode or cathode sheet (AL, KL) and to bring it to a first delivery point (A1); - a stacking table (400) is provided and configured to receive the respective single anode or cathode sheet (AL, KL) at the first delivery point (A1) to form a sheet stack; - the first sheet conveyor (150) is provided and configured to deliver a respective single anode or cathode sheet (AL, KL) to the stacking table (400) at the first delivery point (A1); a fourth image pickup device (K4) is aligned with a fourth region (E4) of the layer stack of anode and cathode layers (AL, KL) in a planar side view of the layer stack and is provided and configured for image introduction after the anode or cathode layer (AL, KL) is deposited on the layer stack on the stack table (400), wherein the fourth region (E4) comprises a corner of an anode or cathode layer (AL, KL) located uppermost on the layer stack and / or a top edge (HK) of the layer stack; and - a fifth image recorder (K5) is aligned with a fifth region (E5) of layer stacks of anode and cathode layers (AL, KL) in a planar side view of the layer stack and is provided and configured for image introduction after the anode or cathode layer (AL, KL) is deposited on the layer stack on the stack table (400), wherein the fifth region (E5) comprises a corner of an anode or cathode layer (AL, KL) located uppermost on the layer stack and / or a top edge (HK) of the layer stack; wherein - the fourth region (E4) or the fifth region (E5) of the anode or cathode layer (AL, KL) in the layer surface comprise regions of the layer stack of anode and cathode layers (AL, KL) lying adjacent or diagonally to one another in a respective side view of the layer stack; and wherein - the inspection device is configured to indicate a (un)current level of the layer stack depending on signaling based on processing of an image registration of the fourth or the fifth image recorder.The inspection device (100) according to claim 1, wherein the layer conveyor comprises a layer inverter (150) provided and configured to receive a respective single anode or cathode layer from the first transfer location (U1) by means of at least one receiver (156) and to rotate a respective rotation angle to the first transfer location (A1).The inspection device (100) according to claim 1, wherein the layer conveyor comprises a layer gripper provided and configured to pick up a respective single anode or cathode layer from the first transfer location (U1) and to bring it to the first discharge location (A1) by means of a pick-up, for example in the form of a suction or gripping tool.The inspection device (100) according to one of the preceding claims, wherein - the fourth image pickup (K4, K4') and / or the fifth image pickup (K5, K5') are adjustable for focusing along their optical axis and / or are movable during operation; and / or - a light source assigned to the fourth image pickup (K4, K4') and / or the fifth image pickup (K5, K5') in each case is determined and configured to lighten the anode / cathode position for a fourth image pick-up or a fifth image pick-up by the fourth image pickup (K4, K4') or the fifth image pickup (K5, K5'); and / or - at least one optically active element is assigned to the fourth image sensor (K4, K4') or fifth image sensor (K5, K5'); wherein - the optically active element is intended and configured to make the corner of the anode or cathode layer (AL, KL) located at the top on the layer stack and / or the top edge (HK) of the layer stack recognizable in the fourth image gate or the fifth image gate after the anode or cathode layer (AL, KL) is deposited on the layer stack; and / or wherein - the at least one optically active element is a lens, or lens arrangement, a mirror or a mirror arrangement, a prism or a prism arrangement, a light guide arrangement, a surface light, a coaxial ring illumination, a dark field illumination, a transmitted light illumination, or a combination thereof.The inspection device (100) according to any one of the preceding claims, wherein - the transmitted light illumination (DL) is arranged on the opposite side of the fourth image pickup (K4, K4') or of the fifth image pickup (K5, K5'), respectively, beyond the position of the corner of the anode or cathode layer (AL, KL) located uppermost on the layer stack and / or the upper edge (HK) of the layer stack, and is configured to take the corner and / or the upper edge (HK) into the light beam path; and / or - by means of processing the fourth image feed or the fifth image feed, to detect a lifting-off, displacement or rotation of the anode or cathode layer (AL, KL), in that the corner and / or the top edge (HK) causes a disturbing contour in the image feed.The inspection device (100) according to one of the preceding claims, wherein - the coaxial ring illumination is arranged on the side of the fourth image sensor (K4, K4') or of the fifth image sensor (K5, K5'), this side of the position of the corner of the anode or cathode layer (AL, KL) located at the top on the layer stack and / or of a top edge (HK) of the layer stack, and is configured to take the corner and / or the top edge (HK) into the light beam path; and / or - by means of processing the fourth image feed or the fifth image feed, to detect a lifting-off, displacement or rotation of the anode or cathode layer (AL, KL), in that the corner and / or the top edge (HK) causes a disturbing contour in the image feed.The inspection device (100) according to any one of the preceding claims, wherein - a first fourth region (E4) and a first fifth region (E5) of the layer stack each comprise a corner of a first edge of the anode or cathode layer (AL, KL) located uppermost on the layer stack and / or of a top edge (HK) of the layer stack on the stack table (400); and / or - a second fourth region (E4') and a second fifth region (E5') of the layer stack each comprise a corner of a second edge of the anode or cathode layer (AL, KL) located on the top of the layer stack and / or of a top edge (HK) of the layer stack on the stack table (400); and / or - one or more fourth or fifth image pickups are arranged in a fixed manner relative to the movable stack table (400); and / or - one or more fourth or fifth image pickups (K4, K5, K4', K5') are connected to the stack table (400) in order to be movable therewith; and / or - one or more fourth or fifth image pick-ups (K4, K5, K4', K5') are oriented at an angle of about ±5° to about ±5° to a longitudinal or transverse edge of the anode or cathode layer (AL, KL) located at the top on the layer stack, for example ±13°.An inspection method in the production of modules or precursors of modules comprises the steps of: - picking up an anode / cathode layer (AL, KL) by means of at least one pick-up (156, 206) of a layer inverter (150, 200) from a transfer point (U1, U2); - dispensing the respective individual anode or cathode layer (AL, KL) from the respective at least one pick-up (156) at a dispensing point (A1, A2) onto a stack table (400) for forming a layer stack when the respective at least one pick-up (156, 206) is located at the dispensing point (A1, A2); directing a fourth image recorder (K4) onto a fourth region (E4) of the layer stack of anode and cathode layers (AL, KL) in a planar side view of the layer stack, wherein the fourth region (E4) comprises a corner of an anode or cathode layer (AL, KL) located at the top of the layer stack and / or a top edge (HK) of the layer stack; and carrying out a fourth image registration after the anode or cathode layer (AL, KL) on the layer stack has been deposited on the stack table (400); and / or - directing a fifth image recorder (K5) onto a fifth region (E5) of the layer stack of anode and cathode layers (AL, KL) in a planar side view of the layer stack, wherein the fifth region (E5) comprises a corner of an anode or cathode layer (AL, KL) located uppermost on the layer stack and / or a top edge (HK) of the layer stack; and - carrying out a fifth image registration after the anode or cathode layer (AL, KL) has been deposited on the layer stack on the stack table (400); and / or wherein - the fourth region (E4) or the fifth region (E5) of the anode or cathode layer (AL, KL) in the layer surface comprise regions of the layer stack of anode and cathode layers (AL, KL) lying adjacent or diagonally to one another in a respective side view of the layer stack; and - indicating a (un)radication of the layer stack depending on signaling based on processing of the fourth or the fifth image input.The inspection method according to the preceding claim, further comprising the steps of: - setting the fourth or the fifth image pickup (K4, K5) for focusing along its optical axis and / or moving the respective image pickup (K4, K5) for focusing along its optical axis during operation; and / or - lightening the fourth or the fifth region (E4, E5) for the fourth or the fifth image registration by the respective image pickup (K4, K5) by means of a light source assigned to the fourth or the fifth image pickup; and / or - associating at least one optically active element with the fourth or the fifth image recorder in order to make the corner of the anode or cathode layer (AL, KL) located uppermost on the layer stack and / or the top edge (HK) of the layer stack recognizable in the fourth or the fifth image holder after the anode or cathode layer (AL, KL) is deposited on the layer stack; and / or wherein - the at least one optically active element is a lens, or lens arrangement, a mirror or a mirror arrangement, a prism or a prism arrangement, a light guide arrangement, a surface light, a coaxial ring illumination, a dark field illumination, a transmitted light illumination, or a combination thereof.The inspection method according to any one of the preceding method claims, further comprising the steps of: - arranging the transmitted light illumination (DL) on the opposite side of the fourth or the fifth image recorder (K4, K5, K4', K5'), respectively, beyond the position of the corner of the anode or cathode layer (AL, KL) located uppermost on the layer stack and / or the upper edge (HK) of the layer stack on the stack table (400), and for this purpose - setting the transmitted light illumination (DL) to take the corner and / or the upper edge (HK) of the layer stack into the light beam path; In order to detect, by means of processing of the fourth or the fifth image registration, an at least partial lifting, displacement or rotation of the anode or cathode layer (AL, KL) located on the top of the layer stack, in which the top corner and / or the top edge (HK) causes a disturbing contour.The inspection method according to any one of the preceding method claims, further comprising the steps of: - arranging the coaxial ring illumination on the side of the fourth or the fifth image sensor (K4, K5, K4', K5'), respectively, this side of the position of the corner of the anode or cathode layer located at the top of the layer stack and / or of the top edge of the layer stack on the stack table, and for this purpose - setting up the transmitted light illumination (DL), to take the corner and / or the top edge (HK) of the layer stack into the light beam path; In order to detect, by means of processing of the fourth or the fifth image registration, an at least partial lifting, displacement or rotation of the anode or cathode layer (AL, KL) located on the top of the layer stack, in which the top corner and / or the top edge (HK) causes a disturbing contour.The inspection method according to any one of the preceding method claims, further comprising the steps of: - picking up an anode / cathode layer (AL, KL) by means of at least one second pick-up (206) of a second layer reversing device (200) from a second transfer point (U2); - dispensing the respective individual anode or cathode layer (AL, KL) from the respective at least one pick-up (206) at a second transfer point (A2) onto the stack table (400) to form the layer stack when the respective second pick-up (206) is located at the transfer point (A2); directing a fourth image recorder (K4') onto a fourth region (E4') of the layer stack of anode and cathode layers (AL, KL) in a planar side view of the layer stack, wherein the fourth region (E4') comprises a corner of an anode or cathode layer (AL, KL) located uppermost on the layer stack and / or a top edge (HK) of the layer stack; and carrying out a fourth image registration after the anode or cathode layer (AL, KL) on the layer stack has been deposited on the stack table (400); and / or - directing a fifth image recorder (K5') onto a fifth region (E5') of the layer stack of anode and cathode layers (AL, KL) in a planar side view of the layer stack, wherein the fifth region (E5') comprises a corner of an anode or cathode layer (AL, KL) located uppermost on the layer stack and / or a top edge (HK) of the layer stack; and - carrying out a fifth image registration after the anode or cathode layer (AL, KL) on the layer stack has been deposited on the stack table (400); and / or wherein - the fourth region (E4') or the fifth region (E5') of the anode or cathode layer (AL, KL) in the layer surface comprise regions of the layer stack of anode and cathode layers (AL, KL) lying adjacent or diagonally to one another in a respective side view of the layer stack; and - indicating a (un)radication of the layer stack depending on signaling based on processing of the fourth or the fifth image input.

Images