Production device for producing battery cells, and method for controlling the production device

Abstract

The invention relates to a production device for producing battery cells, comprising a conveyor device (1) for conveying a film web (3) along a specified web path, wherein the film web (3) is provided in the conveyor device (1) so as to form a plurality of folded layers or cut segments in an alternating arrangement with electrodes provided therebetween in order to form a stack (25); a sensor device (27) with a measuring portion (39) directed onto at least one edge of the film web (3) is provided, having a transmitter unit (30) and a receiver unit (31); a pressing device (36) is provided which forces the film web (3) in the measuring portion (39) into a straight orientation with respect to the transverse extent thereof; and the trasmitter unit (30) and the receiver unit (31) of the sensor device (27) are provided on different sides of the film web (3) and the transmitter field and receiver field thereof are directed onto at least one edge of the film web (3) running through the measuring portion (39).

Description

[0001] Manufacturing equipment for the production of battery cells and method for controlling the manufacturing equipment

[0002] The present invention relates to a manufacturing device for producing battery cells having the features of the preamble of claim 1 and a method for controlling a manufacturing device having the features of the preamble of claim 16.

[0003] Manufacturing equipment for producing battery cells comprises at least one conveying device that conveys a film web, e.g., in the form of a separator web, which is then fitted with electrodes in further processing. The film web is deflected at one or more deflecting devices, whereby the film web should be transported with the most uniform web tension possible. To achieve this uniform web tension, it is known to provide web tension control devices, such as controllable dancers, in the guide of the film web. These dancers have a deflecting device at which the film web is deflected, and their deflection can be controlled to increase or decrease the web tension.

[0004] Since the film web is subject to increased frictional forces at the deflection devices due to surface contact, web tension control is inherently complex. Furthermore, web tension changes caused by frictional forces introduced by a deflection at a deflection device downstream of the web tension control cannot be compensated for. German patent DE 20 2022 100 081 U1 discloses a manufacturing device for battery cells with a Z-folding device. In this device, a film web is continuously fed and then folded around laterally inserted electrode sheets in a pulsed reciprocating motion. The film web is tensioned over a dancer in the feed to the Z-folding device and deflected within the device by a deflection device.The manufacturing device thus has a conveying device with a first conveying section in which the conveying device is designed to convey the film web with a cyclically varying conveying speed due to the movement in the Z-folding device, wherein at least one deflection device is provided in the first conveying section for deflecting the film web.

[0005] Furthermore, the lateral alignment of the film web in the feed to the Z-folding unit can change slightly, for example, due to minor changes in web tension in the edge zones. To compensate for this effect, an additional web edge control system is provided. This system includes a sensor device with a transmitter and a receiver unit, directed at the edge of the film web, which determines the precise current position of the web edge. Depending on this determined position, a web edge control device is then activated to laterally shift the film web, for example, by changing the angle of the film web in a deflection device, thus realigning the film web according to a target position in the feed to the Z-folding unit.If there are waves or folds in the film web, the actual position of the edge will be determined with an error, since the determined actual position differs from the true actual position of the undistorted, flat film web, which results after the waves have been pulled out.

[0006] Furthermore, there is the problem that film webs which have different material properties on their two surface sides, such as different resistances to deformation or coefficients of thermal expansion due to a one-sided coating or different coatings, tend to roll unilaterally towards the center of the film web at the edges.

[0007] Such lateral rolling of the film web can also occur if different tensile forces occur in the film web across the transverse stretching, e.g. in the case of one-sided pulling of the film during a deflection.

[0008] In the described cases, the actual position of the rolled edge does not correspond to the actual position of the edge on a smoothed film web with a non-rolled edge. This error in determining the actual position of the edge then leads, if a subsequent web edge control device is controlled accordingly, to an incorrect correction of the lateral alignment of the film web, which in turn leads to an incorrect lateral alignment of the smoothed layers of the film web in the battery cell.

[0009] Against this background, the invention is based on the objective of providing a manufacturing device for producing battery cells, which enables the production of the battery cells with a further improved alignment of a film web within the battery cells with respect to a predetermined target position. To achieve this objective, a manufacturing device with the features of claim 1 and a method for controlling such a manufacturing device with the features of claim 16 are proposed. Further preferred developments can be found in the dependent claims, the figures, and the accompanying description.

[0010] To solve the problem, a manufacturing device for producing battery cells is provided, comprising a conveying device for conveying a film web along a predetermined web path, wherein the film web in the conveying device is arranged in a stack of a plurality of folded layers or cut segments in a changing arrangement with electrodes arranged between them, wherein a sensor device with a measuring section directed towards at least one edge of the film web is provided, comprising a transmitter unit and a receiver unit, wherein a pressure device is provided which forces the film web in the measuring section into a straight orientation with respect to its transverse extent, and the transmitter unit and the receiver unit of the sensor device are arranged on different sides of the film web and are directed with their transmitter field and receiver field towards at least one edge of the film web passing through the measuring section.

[0011] The advantage of the proposed solution lies in the fact that the film web is pressed flat into a straight alignment by the pressure device in the measuring section of the sensor device, thus eliminating any existing waves or curvatures in the edge sections and in the middle of the film web. This flattens the film web to its maximum width and forces the edge into its true position. This results in precise alignment of the film web edge in its actual position. Without a corresponding subsequent correction of the film web's lateral alignment by a suitable control system, this would also occur in the stack of numerous layers or segments of film web in the battery cell due to inaccurate determination of the actual position caused by waves.By flattening the film web, the actual position of the film edge can be determined beforehand, according to its arrangement in the battery cell. If the actual position deviates from the target position, this can then be corrected by controlling a web edge control device. Thus, flattening the film web and removing any waves or curves in the web forms the basis for accurately determining its actual position. This, in turn, is the basis for precisely controlling the web edge control device to correct the edge position of the film web and thus ensure the precise alignment of the layers or segments of the film web within the battery cell.

[0012] Furthermore, the sensor device, with the proposed arrangement of the transmitter and receiver units on opposite sides of the film web and the alignment of the transmitter and receiver fields with the flattened edge, is specifically designed and aligned to determine the position of the flattened edge in its true actual position. Waves and curvatures in the film web are deliberately eliminated by pressing and applying pressure to the web. The edge runs through the measuring section and thus through the transmitter and receiver fields between the transmitter and receiver units. Therefore, the influence of the transmitter field on the receiver unit depends directly on the position of the film edge between the transmitter and receiver units. Thus, the signal from the receiver unit represents the true actual position of the film edge.Based on this determined actual position of the edge of the film web, it is then possible to control the lateral alignment of the film web much more precisely according to a predetermined target position of the edge by means of the subsequent web edge control device.

[0013] It is further proposed that the transmitter unit and the receiver unit be fixed to a holder in a position relative to each other. This defines the orientation of the transmitter unit to the receiver unit and vice versa, and allows for the generation of a correspondingly precise signal representing the position of the edge of the film web.

[0014] It is further proposed that the transmitter and receiver units be fixed in position relative to the pressure device. This ensures that the transmitter and receiver units are fixed in position relative to both the pressure device and the film web pressed against it into a straight alignment. Consequently, any signal change from the sensor is solely attributable to a relative movement of the film web. For a particularly simple design, the transmitter and receiver units can be fixed to each other and, using the same mounting bracket, also to the pressure device.

[0015] It is further proposed that a window be provided in the pressure device, which passes over the edge of the film web, and that the transmitter and receiver units, with their transmitter and receiver fields respectively, are directed through the window toward the edge of the film web. The actual position of the film web's edge can be directly determined through the window, since the film web is precisely flattened in the pressure device and thus positioned with its edge in its actual position within it. The window provided in the pressure device deliberately exposes the film web's edge in its actual position, so that the transmitter and receiver units can be easily directed at the film web's edge from different sides, and the signal in the receiver unit is influenced solely by the position of the film web's edge.

[0016] It is further proposed that the pressure device be formed by a deflection device connected to a compressed air system, featuring a porous pressure surface against which the film web is deflected under compressed air. Ideally, the proposed design of the pressure device allows the film web to be deflected without contact, forming an air cushion and forcing it into a straight alignment in its transverse dimension. During deflection, the film web is automatically forced into this straight alignment by the tensile forces acting within it. The air cushion guides and deflects the film web without contact, allowing the use of a stationary deflection device without increasing friction. Additional force applied to the film web, such as...The use of compressed air is generally not required, although the smoothing effect of the film web by the compressed air stream and the air cushion formed can be further supported by applying a surface pressure force to the film web.

[0017] It is further proposed that the air-permeable circumferential section be formed by a field of air outlet openings distributed circumferentially and axially around the compressed air beam. This proposed design of the air-permeable circumferential section allows air to flow uniformly over a defined circumferential section of the compressed air beam's surface, forming an air cushion of as constant a thickness as possible between the surface and the film.

[0018] The air cushion or air pillow can be formed particularly well and uniformly by incorporating a porous material structure into the air-permeable circumferential section of the compressed air beam. The air outlet openings are formed by the cross-sectional areas of spaces or pores within this porous material structure on an outer surface of the compressed air beam. This porous material structure can, for example, be sponge-like with a chaotic distribution and connection of individual partial flow channels and pores, making it much more cost-effective to manufacture, as precise flow channel configurations are unnecessary. The porous material structure can be produced, for instance, through a sintering process involving the simple melting of a mass of coarse-grained metal particles.

[0019] It is further proposed that the compressed air beam has continuous compressed air channels in the air-permeable circumferential section, with the air outlet openings formed by the cross-sectional areas of these compressed air channels on an outer surface of the compressed air beam. The compressed air channels enable a controlled and directed flow of air through and out of the air-permeable circumferential section, thus allowing for a controlled build-up of the air cushion to a predetermined thickness.

[0020] To form an air cushion with a thickness that is as constant as possible, it is further proposed that the air outlet openings each have an average cross-sectional area of ​​0.004 to 0.1 mm². 2 preferably from 0.01 to 0.06 mm 2 , particularly preferably from 0.02 to 0.04 mm 2exhibit. The determined cross-sectional area refers to the cross-sectional area of ​​the individual air outlet openings and thus determines the outflow conditions of the air from each air outlet opening.

[0021] Furthermore, to form an air cushion with a constant thickness, it is preferred that the air outlet openings together constitute a total area of ​​20 to 80 percent, preferably 40 to 60 percent, and particularly preferably 45 to 55 percent of the total area of ​​the air-permeable circumferential section.

[0022] It is further proposed that the extension angle of the air-permeable circumferential section in the circumferential direction of the pneumatic beam corresponds at least to the intended wrapping angle of the film web on the pneumatic beam, so that the film web is guided over the air cushion at a distance without contact over its entire wrapping angle relative to the pneumatic beam.

[0023] It is further proposed that the compressed air system be designed and configured to pressurize the compressed air beam, and thus the air-permeable section, with an air pressure of 1.1 to 1.5 bar. The proposed air pressure thus creates a driving pressure difference of 0.1 to 0.5 bar compared to the ambient pressure assumed to be 1.0 bar, which is sufficient for the formation of the air cushion.

[0024] It is further proposed that the compressed air device 35 be configured and designed to supply the compressed air beam with a volume flow of 40 to 100 l / min, preferably 70 to 100 l / min, and particularly preferably 70 to 80 l / min. The proposed volume flow ranges allow the air cushion to be reliably constructed in relation to the forces acting on the film web during deflection or the web tension acting on the film web.

[0025] It is further proposed that the window be arranged in the pressure surface, and the transmitter or receiver unit be arranged in the deflection device. By designing the pressure device as a compressed air deflection device with a porous pressure surface, the film web can be deflected without contact, i.e., via an air cushion, allowing the deflection device to be stationary. This fact is then utilized to allow the transmitter or receiver unit to be arranged in the stationary deflection device. By arranging the window in the pressure surface, the edge of the film web can be exposed precisely in the area where the film web is deflected, forming the air cushion.

[0026] The invention is explained below with reference to preferred embodiments and the accompanying figures. Figure 1 shows a manufacturing device according to the invention in a first representation, and

[0027] Fig. 2 shows a manufacturing device according to the invention in a second representation, and

[0028] Fig. 3 shows a schematic representation of the manufacturing device with a pressure device and a sensor device, and

[0029] Fig. 4 shows an enlarged view of a pneumatic beam with a foil web deflected along it, and

[0030] Fig. 5 shows an enlarged view of the pneumatic beam with the film web and two sensor devices on a bracket, and

[0031] Fig. 6 shows an enlarged view of the pneumatic tube with the foil web, a sensor device and a window in the pneumatic tube, and

[0032] Fig. 7 shows a first alternative embodiment of a pressure device, and

[0033] Fig. 8 shows a second alternative embodiment of a pressure device.

[0034] Figures 1 and 2 show a manufacturing device according to the invention with a conveying device 1 with a pull roller 28, a tensioning device 4, a Z-folding device 2 and a film web 3 fed in the conveying device 1 to the Z-folding device 2.

[0035] The film web 3 is deflected multiple times in the conveyor 1 via a plurality of deflection devices 5, 8, 6, 7 arranged one after the other in the direction of the film web 3's travel, before being fed to the Z-folding device 2. The film web 3 can, for example, have a thickness of 10 to 25 µm and an air permeability of 100 to 300 Gurley seconds. The air permeability can be measured, for example, with a Gurley™ Densometer 40N, available from RYCOBEL GROUP. Exemplary film webs 3 are known on the market, for example, from the companies Celgard or Entek.

[0036] The tensioning device 4 comprises a stationary deflection device 8 and a dancer 19 with a deflection device 5. The deflection device 5 of the dancer 19 is connected at its ends to a drive unit 22 via pivot arms 21 and 23, respectively. When the drive unit 22 is activated, the deflection device 5 can be pivoted via the pivot arms 21 and 23. By pivoting the deflection device 5, the web tension in the film web 3 can be decreased or increased. Subsequently, the film web 3 is guided by two spaced-apart deflection devices 6 and 7 and is deflected twice in opposite directions to form an S-shaped path.

[0037] The film web 3 is then fed to the Z-folding device 2, where it is folded into a Z-fold in a reciprocating folding motion. Simultaneously, anodes and cathodes are alternately inserted into the folds of the film web 3 from opposite sides. The Z-folding device 2 has two folding brackets 11 and 12 with two parallel deflection devices 9 and 10 held between them. These deflection devices are positioned close together with a gap of constant width along their longitudinal extent. Each folding bracket 11 and 12 is connected to a drive unit 16 and 17 in the form of a servomotor, which, when activated, drives the folding brackets 11 and 12 and the deflection devices 9 and 10 attached to them into a reciprocating pivoting motion.The film web 3 is deflected at a final deflection device 7 in the feed to the Z-folding device 2 and guided between the deflection devices 9 and 10 of the folding brackets 11 and 12 to a stack 25 on a delivery table, around which the folding brackets 11 and 12 pivot. The film web 3 is periodically folded into the Z-fold in a reciprocating folding motion, with the film web 3 being deflected at either the deflection device 9 or the deflection device 10 depending on the position of the folding brackets 11 and 12.

[0038] The last deflection device 7, at which the film web 3 is deflected before entering the Z-folding device 2, is arranged such that the film web 3, deflected at the outer surface 20, runs in its vertical extension along a perpendicular S of the Z-folding device 2, which passes through the pivot axes SA of the folding brackets 11 and 12. In their basic movement, the folding brackets 11 and 12 perform a pivoting movement about the pivot axis SA that is symmetrically aligned with the perpendicular S. This means that the pivot angles of the folding brackets 11 and 12 are identical from the perpendicular S to the right and left sides, i.e., to the two edge sides of the insertion compartments of the film web 3. Thus, during the folding movement, the film web 3 is folded by the same length to the left and right, resulting in identical changes in web tension in the film web 3, the maximum value of which is, however, limited to the lowest possible value.

[0039] At least one of the deflection devices 5, 6, 7, 8, 9, 10 is designed as a compressed air beam 34, which can be seen in Fig. 4, which is connected to a compressed air device 35 shown only in Fig. 5 and can be pressurized with an overpressure of 1.1 to 1.5 bar.

[0040] In the feed device 1, a measuring device is provided at the first deflection device 8 located downstream of the dancer 19. The deflection device 8 is formed by a deflection section supported at both ends. In this case, the measuring device consists of two load cells assigned to the supports of the deflection section, which determine the pressure exerted by the film web 3 on the deflection device 8 and thus the web tension in the film web 3. The load cells are deliberately designed with a high measuring capacity to generate a measurement signal that is as linear as possible within a measuring range of a few Newtons and a deviation of 10 ± 2 N from the required web tension.

[0041] The film web 3 is folded in the Z-folding device 2 in a reciprocating motion, whereby the dancer 19, depending on the design, is controlled in the deflection of the deflecting device 5 via the pivot arms 21 and 23 in relation to the change in length of the film web 3 caused by the movement of the Z-folding device 2, either in the Z-folding device 2 or in the conveyor 1. The film web 3 is folded into a Z-shape by the Z-folding device 2 in a reciprocating, timed folding motion, whereby the movement of the Z-folding motion introduces additional changes in length and thus fluctuations in web tension into the film web 3 in the Z-folding device 2 itself or into the feed to the Z-folding device 2. These changes in length or web tension fluctuations are then compensated by the control of the dancer 19 in the feed of the foil web 3 to the Z-folding device 2, i.e. before they arise, and ideally reduced to zero.

[0042] The feeding device 1 thus has a first conveying section 24 in which the film web 3 is transported at a cyclically varying conveying speed. In the present embodiment, the first conveying section 24 is the section between the dancer 19 and the discharge table, on which the Z-folding device 2 folds the film web 3 into the stack 25.

[0043] Between the dancer 19 and the Z-folding device 2, a plurality of deflection devices 8, 6, 7 are provided in the first conveying section 24, which are preferably all designed as pneumatic beams 34. This ensures that the film web 3 is deflected downstream to the dancer 19 in the feed to the Z-folding device 2 exclusively without contact via air cushions 15, i.e., with minimal friction against the pneumatic beams 34. This minimizes any further changes in web tension introduced into the film web 3 after it has exited the dancer 19 during subsequent deflections.

[0044] At least one of the deflection devices 5, 6, 7, 8, 9, 10 is designed as a compressed air beam 34, which is shown by way of example in Fig. 4. The compressed air beam 34 is connected to the compressed air device 35 shown in Fig. 5 and can be pressurized with an overpressure of 1.1 to 1.5 bar via this device.

[0045] The pneumatic strut 34 has an air-permeable circumferential section 14, which extends over an angle of extension A in the circumferential direction of the pneumatic strut 34. The air-permeable circumferential section 14 has a plurality of air outlet openings arranged axially and circumferentially, each with an average opening diameter of 0.02 to 0.1 mm. The air outlet openings are axially and radially offset from one another, in a uniform field distribution of 100 to 300 air outlet openings per cm² within the circumferential section 14 on the pneumatic strut 34. The circumferential section 14 can be manufactured, for example, by a laser sintering process.

[0046] The film web 3 is deflected at the outer surface 18 of the pneumatic tube 34. In one embodiment, the pneumatic tube 34 has a cavity 29 which radially defines the inner boundary of the air-permeable circumferential section 14 and is thus fluidically connected to it. When compressed air is applied to the cavity 29 of the pneumatic tube 34, the air flows out of the air-permeable circumferential section 14 and forms an air cushion 15 between the film web 3 and the outer surface 18 of the pneumatic tube 34. This causes the film web 3 to lose contact with the outer surface 18 and be deflected without contact at the pneumatic tube 34. This significantly reduces the frictional forces acting on the film web 3 during deflection at the pneumatic tube 34, which in turn reduces the influence of these frictional forces on the web tension in the film web 3.

[0047] Alternatively, the compressed air beam 34 can also be designed, at least in the area of ​​the air-permeable circumferential section 14, completely, i.e., up to the core, as a porous material structure in the manner of a sponge or a closely meshed grid structure, whereby the air then flows in from the compressed air device at a point in the porous material structure and flows out again over the outer surface of the compressed air beam 34 to form the air cushion 15.

[0048] Furthermore, the pneumatic beam 34 can very easily also be provided as a deflection device 5 of the dancer 19 or another tensioning device 4, which can be arranged at any point on the conveying device 1 or the Z-folding device 2. In this case, the web tension in the film web 3 can be controlled very simply by controlling and changing the air pressure in a cavity 29 or the porous material structure of the pneumatic beam 34. The web tension is increased by increasing the air pressure in the cavity 29, as this increases the thickness of the air cushion 15 and thus the unwound length of the deflected section of the film web 3. In other words, this increases the pressure force exerted on the film web 3, which displaces the film web 3 radially outwards and increases the web tension in the film web 3.A reduction in web tension is then achieved in reverse by reducing the air pressure in the cavity 29. Furthermore, the use of the pneumatic beam 34 as a deflection device 5 in the dancer 19 offers the advantage that the previously required drive unit 22 and the pivot arms 21 on the dancer 19 can be omitted. Additionally, the pneumatic beam 34, in conjunction with a distance sensor 13 directed externally at the film web 3 deflected by the pneumatic beam 34, can also be used as a web tension sensor device, by detecting the distance to the film web 3.The distance between the distance sensor 13 and the film web 3 is directly dependent on the web tension in the film web 3 for a defined air pressure in the cavity 17 or in the porous material structure. This is because, when the web tension increases, the film web 3 is forced towards the outer surface 18 of the compressed air beam 34, thereby increasing the distance to the distance sensor 13 and decreasing the thickness of the air cushion 15. Conversely, when the web tension decreases, the distance between the film web 3 and the distance sensor 13 is reduced accordingly. The web tension in the film web 3 is preferably 10 ± 2 N.

[0049] According to the invention, one of the deflection devices 5, 6, 7, 8, 9, 10 is used as a pressure device 36, on which the film web 3 is deliberately forced into a straight orientation in transverse extension due to the pressure forces acting on the film web 3 during the deflection, which in turn are generated in the deflection device 5, 6, 7, 8, 9, 10 due to the tensile forces acting in the film web 3 during the deflection, as can be seen in the enlarged view of Figure 3. If the deflection device 5, 6, 7, 8, 9, 10 is additionally designed as a compressed air beam 34, as can be seen in Figures 5 and 6, a planar compressive force is additionally exerted on the film web 3 by the compressed air flow flowing out of the compressed air beam 34 and the air cushion 15 formed therein between the film web 3 and the outer surface 18 of the compressed air beam 34, so that the film web 3 is additionally forced into a flat, planar orientation with respect to its transverse extent.This flattens any waves and, in particular, curvatures present in the film web 3, especially in the edge sections, so that the film web 3 is compressed to its maximum width. This corrects the orientation of the edge of the film web 3 to such an extent that, regardless of any waves or curvatures present in the film web 3, it corresponds to the true actual position in which it would subsequently be folded without any corresponding downstream adjustment.

[0050] Furthermore, two windows 32 are provided in the lateral surface 18 of the deflecting device 5, 6, 7, 8, 9, 10, which are arranged such that the film web 3 passes over the windows 32 with its edges corrected in alignment by "flattening". The lateral surface 18 of the deflecting device 5, 6, 7, 8, 9, 10 thus practically forms a pressure surface of the pressure device 36, against which the film web 3 rests, depending on its design, either directly or indirectly via an air cushion 15, either as a compressed air bar 34 or not. If the manufacturing device is to be simplified, it would also suffice to determine only the true actual position of one of the two edges, i.e., to provide only one window 32 and a pair of a transmitter unit 30 and a receiver unit 31, since the actual position of the other edge can be indirectly determined from the actual position of the determined position of one edge, given the width of the film web 3.

[0051] In the embodiment shown in Figure 3, the pressure device 36 is implemented by the deflecting device 8, from which the film web 3 is fed further to the deflecting devices 6 and 7, from which the film web 3 is then fed directly to the Z-folding device 2. A transmitter unit 30 of a sensor device is arranged in the deflecting device 8, the transmitter field of which is directed through the window 32 towards the edge of the film web 3 as it passes over the window 32. A receiver unit 31 is arranged on the opposite side of the film web 3, the receiver field of which is also directed towards the edge of the film web 3.

[0052] The receiver unit 31 is arranged such that its receiver field overlaps with the transmitter field of the transmitter unit 30. Thus, the edge of the film web 3 runs between the transmitter unit 30 and the receiver unit 31 within the transmitter field and overlaps the receiver field, with the signal generated in the receiver unit 31 depending on the orientation of the edge within the transmitter field of the transmitter unit 30. The transmitter unit 30 and the receiver unit 31 therefore form a sensor device 27 that determines the orientation of the edges of the film web 3. This sensor device, with a measuring section 39 defined by the transmitter field of the transmitter unit 30 and the receiver field of the receiver unit 31, is directed precisely at the edge of the film web 3 flattened by the pressure device 36 and thus determines the true actual position of the edge of the film web 3.Alternatively, it would also be conceivable to determine only the orientation of one of the edges of the foil web 3, since the orientation of the second opposite edge can be indirectly determined from the orientation of the first edge, taking into account the known width of the foil web 3.

[0053] The core of the proposed solution lies in first flattening the film web 3 using the pressure device 36, thus eliminating any existing waves and curvatures in the film web 3, and then precisely aligning the sensor device 27 with its measuring section 39 onto the edge of the film web 3 flattened by the pressure device 36 in order to determine the true actual position of the edge of the film web 3. This eliminates the signal-distorting influences of waves and curvatures on the actual position of the edge, and allows the precise actual position of the edge to be determined, which then forms the basis for the subsequent precise control of the alignment of the film web 3 and thus the alignment of the film web in the finished stack 25 of the battery cell.

[0054] If the actual position of one or both edges, as determined in this way, deviates from a predetermined target position, the orientation of the film web 3 is then corrected by a corresponding web edge control device. The web edge control device can, for example, be a drive device for pivoting one or both of the subsequent deflection devices 6 and / or 7.

[0055] The transmitter unit 30 and receiver unit 31 of the sensor device 27, which can be seen in cross-section in Figure 6, are preferably attached to a common holder 33, which can be seen in Figure 5, so that the transmitter field of the transmitter unit 30 and the receiver field of the receiver unit 31 are arranged and aligned in a fixed spatial relationship to each other.

[0056] The pressure device 36 can alternatively be formed by a sufficiently narrow slit between two pressure surfaces; the only important point is that the pressure device 36 forces the film web 3 into a flat orientation with respect to its transverse extent, and that the sensor device 27 is then directed with its measuring section 39 towards the flattened edge of the film web 3. Figures 7 and 8 show two alternative embodiments of the pressure device 36. The pressure device 36 in Figure 7 is formed by a body with a multiple deflection contour 37 in the form of two curved, projecting deflection surfaces with a valley arranged between them, wherein the film web 3 is exposed over a short section of its path above the valley.The transmitter unit 30 is held on the multiple deflection contour such that its transmitter field is directed through the valley towards the exposed edge of the film web 3, while the receiver unit 31 is arranged on the opposite side of the edge of the film web 3 and its receiver field is directed towards the same edge, but from the other side. The film web 3 is deflected twice at the multiple deflection contour 37 and thereby forced into a flat, planar orientation with respect to its transverse extent.

[0057] In Fig. 8, the pressure device 36 is formed by a deflection baffle with a double, oppositely directed deflection of the film web 3, wherein the film web 3 runs in a taut and flattened orientation in a free section between the deflections. The transmitter unit 30 and the receiver unit 31 are directed at the edge(s) of the film web 3 from different sides and determine the actual position of the flattened edge(s) in the manner described above.

[0058] Furthermore, in both embodiments, a second sensor device 40 is additionally provided, which determines the actual position of the edge of the film web 3 after it has passed through the deflection devices 6 and 7. If this determined actual position deviates from a predetermined target position, the web edge control device, e.g. formed by an adjustment device of the deflection devices 6 and 7, is activated and the orientation of the film web 3 is additionally corrected accordingly in the pre-run.

[0059] 1 funding facility

[0060] 2 Z-folding device

[0061] 3 foil strips

[0062] 4 Clamping device

[0063] 5 Deflection device

[0064] 6 Deflection device

[0065] 7 Deflection device

[0066] 8 Deflection device

[0067] 9 Deflection device

[0068] 10 Deflection device

[0069] 11 folding bars

[0070] 12 folding bars

[0071] 13 Distance sensor

[0072] 14 Scope section

[0073] 15 air cushions

[0074] 16 Drive unit

[0075] 17 Drive unit

[0076] 18 lateral surface area

[0077] 19 dancers

[0078] 20 lateral surface area

[0079] 21 Swivel arm

[0080] 22 Drive unit

[0081] 23 Swivel arm

[0082] 24 First funding phase

[0083] 25 stacks

[0084] 26 hold-down devices

[0085] 27 Sensor device

[0086] 28 Pulley roller

[0087] 29 Cavity

[0088] 30 Transmitter unit 31 Receiver unit

[0089] 32 windows

[0090] 33 bracket

[0091] 34 Pneumatic pole

[0092] 35 Compressed air device

[0093] 36 Pressure device

[0094] 37 Multiple deflection contour

[0095] 38 Deflection chicane

[0096] 39 Measuring section 40 Second sensor device

[0097] A Extension angle

[0098] S Perpendicular

[0099] SA swivel axis

Claims

Claims:

1. Manufacturing apparatus for the production of battery cells, comprising a conveying device (1) for conveying a film web (3) along a predetermined web path, wherein -the film web (3) in the conveying device (1) is arranged into a stack (25) of a plurality of folded layers or cut segments in a changing arrangement with electrodes arranged between them, wherein -a sensor device (27) with a measuring section (39) directed towards at least one edge of the film web (3) is provided, comprising a transmitter unit (30) and a receiver unit (31), characterized in that -a pressure device (36) is provided which forces the film web (3) in the measuring section (39) into a straight alignment with respect to its transverse extent, and -the transmitter unit (30) and the receiver unit (31) of the sensor device (27) are arranged on different sides of the film web (3) and are directed with their transmitter field and receiver field towards at least one edge of the film web (3) passing through the measuring section (39).

2. Manufacturing device according to claim 1, characterized in that -the transmitter unit (30) and the receiver unit (31) are fixed to each other on a bracket (33).

3. Manufacturing device according to claim 1 or 2, characterized in that -the transmitter unit (15) and the receiver unit (14) are fixed in position relative to the pressure device (36).

4. Manufacturing device according to claims 1 to 3, characterized in that -the pressure device (36) has a window (32) which passes over the edge of the film web (3), and -the transmitter unit (30) and the receiver unit (31) with their transmitter field and receiver field are directed through the window (32) towards the edge of the foil web (3).

5. Manufacturing device according to one of claims 1 to 4, characterized in that -the pressure device (36) is formed by a deflection device (5,6,7,8,9,10) connected to a compressed air device (35) with a porous pressure surface, on which the film web (3) is deflected under compressed air.

6. Manufacturing device according to claim 5, characterized in that -the deflection device (5,6,7,8,9,10) is designed as a compressed air beam (34) that can be connected to or is connected to the compressed air device (35), and -the porous pressure surface is formed by an air-permeable circumferential section (14) of the compressed air beam (34).

7. Manufacturing device according to claim 6, characterized in that -the air-permeable circumferential section (14) by a field limited in the circumferential and axial directions of the compressed air beam (34) It is formed by distributed air outlet openings.

8. Manufacturing device according to claim 7, characterized in that -the compressed air beam (34) has a porous material structure in the air-permeable circumferential section (14), wherein the air outlet openings are formed by the cross-sectional areas of spaces or pores of this porous material structure on an outer surface of the compressed air beam (34).

9. Manufacturing apparatus according to one of claims 7 or 8, characterized in that -the compressed air beam (34) has continuous compressed air channels in the air-permeable circumferential section (14), wherein -the air outlet openings are formed by the cross-sectional areas of these compressed air channels on an outer surface of the compressed air beam (34).

10. Manufacturing device according to one of claims 7 to 9, characterized in that -the air outlet openings each have an average cross-sectional area of ​​0.004 to 0.1 mm² 2 preferably from 0.01 to 0.06 mm 2 , particularly preferably from 0.02 to 0.04 mm 2 exhibit.

11. Manufacturing apparatus according to one of claims 7 to 10, characterized in that -the air outlet openings together constitute an area share of 20 to 80 percent, preferably 40 to 60 percent, particularly preferably 45 to 55 percent of the total area of ​​the air-permeable circumferential section (14).

12. Manufacturing apparatus according to one of claims 6 to 11, characterized in that -the extension angle (A) of the air-permeable circumferential section (14) in the circumferential direction of the pneumatic tube (34) corresponds at least to the intended wrapping angle of the film web (3) on the pneumatic tube (34).

13. Manufacturing apparatus according to one of claims 6 to 12, characterized in that -the compressed air device (35) is designed and configured to apply an air pressure of 1.1 to 1.5 bar to the compressed air shaft (34).

14. Manufacturing apparatus according to one of claims 6 to 13, characterized in that -the compressed air device (35) is configured and designed to supply the compressed air shaft (34) with a volume flow of 40 to 100 l / min, preferably 70 to 100 l / min, particularly preferably 70 to 80 l / min.

15. Manufacturing apparatus according to claim 4 and according to any one of claims 5 to 14, characterized in that -the window (32) is arranged in the pressure surface, and -the transmitter unit (30) or the receiver unit (31) is arranged in the deflection device (5,6,7,8,9,10).

16. Method for controlling a manufacturing device according to one of claims 1 to 15, characterized in that -that a web edge control device is provided which depends on the signal from the receiver unit (31) the sensor device (27) is controlled.

17. Method according to claim 16, characterized in that -a second sensor device (40) is provided which determines the actual position of the edge of the film web (3) after passing through the web edge control device, and -the web edge control device is controlled depending on the signal of the second sensor device (40).

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