Positioning device, stacking device and stacking method for repeating parts of cell stack of battery cells or fuel cell cells

Abstract

The invention relates to a positioning device and to a stacking device for positioning repeating parts to be placed on one another of a cell stack for battery cells or fuel cell cells, and to a stacking method for forming a cell stack for battery cells or fuel cell cells from a plurality of repeating parts to be placed on one another. The device and the method should be adapted to the properties of repeating components and enable not only a higher degree of damage-free alignment of the components but also a simplified adaptation of component variations. In order to solve the problem, according to the invention, at least one elastic element is provided, which is designed such that when a repeating component introduced into the positioning device is introduced into the positioning device in a plane transverse to the repeating component, the edge of the introduced repeating component impinges on the at least one elastic element, and the edge of the repeating component impinges on the at least one elastic element. The at least one elastic element brakes a repeating part introduced into the positioning device; and at least one positioning element is provided, which can be vibrated by means of the vibration generator such that at least one edge of the introduced repeating part is aligned with a corresponding edge of the repeating part that has been introduced.

Description

Technical Field

[0001] The invention relates to a positioning device for positioning repetitive components to be placed on top of each other for a cell stack of battery cells or fuel cell cells. In addition, the invention relates to a stacking device for forming a cell stack of battery cells or fuel cell cells from repetitive components to be placed on top of each other, the stacking device having at least one such positioning device. Finally, the invention relates to a stacking method using such a stacking device. Background Art

[0002] In the field of automated production of fuel cell cells, the so-called stacking assembly field, the pick-and-place method for producing fuel cell stacks is mainly used. The principle of the pick-and-place method is that repeating units including bipolar plates and / or membrane electrode units are stacked alternately or alternately on each other or on edge parts by grabbing, transporting, positioning and putting down until the corresponding required number of cells is reached. In this case, the end plate is called an edge part, which forms the termination of the repeating units connected in series or the single cell layer formed thereby. Further components that may be required for the function of the fuel cell stack can be integrated in the end plate. For example, the further components can be current collectors and / or monopolar plates and / or pressure distribution plates.

[0003] Although pick and place systems ensure permanent guidance of repeated components via fixtures, they are not suitable for mass production with regard to the requirements for reduced cycle times.Alternative systems for stack formation without fixtures require equipment for defined alignment and positioning of the cell components.

[0004] From EP21197541 A1, it is known to position the repeated parts to be placed on each other for battery cell stacking or fuel cell stacking. Here, the device for aligning the parts is composed of a shaking clamp that can be placed in vibration by means of a vibration generator and a rigid positioning clamp arranged below the shaking clamp. The shaking clamp and the positioning clamp respectively have a contact surface for abutting against the edge of the repeated parts to be placed. The shaking clamp that can be placed in vibration is used to vibrate the repeated parts to be put down, and at least one positioning clamp keeps the parts in its position during the continuous stacking process. Disadvantageously, the shaking clamp and the positioning clamp are rigid, so that the damage at the parts is not completely eliminated due to the non-flexibility of the clamp when the parts hit the contact surface of the clamp. In addition, the shaking clamp with a vibration generator has a high position requirement at the stacking position, and when matching, for example, with other specifications or materials of the repeated parts, a large modification cost is generated to match the clamp and the vibration element. Summary of the invention

[0005] The object on which the present invention is based is therefore to provide a device and a method in which the mentioned disadvantages are overcome in that the positioning device and the positioning method are adapted to the properties of the repetitive components and allow not only a more highly damage-free alignment of the components but also a simplified adaptation to component changes.

[0006] This object is achieved by a positioning device having the features of claim 1 and by a stacking device having the features of claim 9 and by an associated stacking method having the features of claim 10. Further features of the invention are derived from the dependent claims.

[0007] The present invention realizes a positioning device for positioning repetitive components to be placed on each other for a cell stack for a battery cell or a fuel cell. The production of fuel cells in this case particularly relates to membrane electrode assemblies (also referred to as MEAs) or bipolar plates (BPPs). The production of battery cells in particular relates to electrodes (anodes or cathodes) and separators. The individual repetitive components can also consist of a composite of the components, and for battery cell production, the repetitive components can also consist of a prefabricated stack of electrodes and separators, for example. In order to form a stack from the components, the repetitive components are introduced into a positioning device, aligned by the positioning device, and maintained in their position and orientation within the stacking device. The introduction of the components into the positioning device can, for example, be carried out transversely to the plane of the repetitive components already in the stack.

[0008] The positioning device according to the invention comprises at least one elastic element, which brakes the repetitive component introduced into the positioning device when the edge of the repetitive component introduced into the positioning device hits the at least one elastic element when the repetitive component is introduced into the positioning device transversely to the plane of the repetitive component. Here, the elastic element can be elastically deformed so that damage to the edge of the repetitive component introduced can be avoided. The material and geometry of the elastic element are implemented so that it is flexible and attenuates the collision of the repetitive component onto the element. The kinetic energy of the repetitive component introduced is reduced, thereby preventing damage to the component.

[0009] Furthermore, the positioning device has at least one positioning element which can be set into vibration by a vibration generator such that at least one edge of an introduced repeating component is aligned relative to a corresponding edge of an already introduced repeating component.

[0010] According to another aspect, the present invention realizes a stacking device for forming a cell stack for battery cells or fuel cell cells by repeated components to be placed on each other, the stacking device includes at least one positioning device and a receiving portion according to the above-mentioned design scheme, the receiving portion has a supporting device movable in the height direction, and the supporting device is used to support and adjust the height of the cell stack during stacking.

[0011] According to another aspect, the invention implements a stacking method for forming a cell stack for a battery cell or a fuel cell from a plurality of repeating components to be placed on each other, the stacking method comprising:

[0012] a) setting up a stacking device according to the above design scheme,

[0013] b) Drop the duplicate parts,

[0014] c) centering the repeating element by means of the vibrations of the rocking jaws, so that the repeating element comes to bear against the positioning jaw bearing surface,

[0015] e) Repeating steps a) to c) with further repeating components, in order to thereby form a cell stack.

[0016] Preferably, the stacking method comprises the following steps to be performed after step c):

[0017] d) Moving the support device downwards, wherein in step e) steps a) to d) are repeated with further repeating elements.

[0018] According to an advantageous design of the positioning device according to the invention, at least one positioning element is simultaneously designed as at least one elastic element. The positioning element can be controlled by a vibration unit, which puts the positioning element into vibration, by which the introduced repeating component is aligned relative to the edge of the already introduced repeating component. At the same time, the positioning element is implemented elastically, so that the impact of the introduced repeating component can be reduced. Thus, the alignment of the repeating components can be achieved by means of vibration and impact reduction by a single component of the device. Therefore, the positioning device can be used not only for operations with alignment of the repeating components by means of vibrations generated by the vibration unit, but also for operations with alignment only by the flexibility of the elastic element.

[0019] According to another advantageous design of the positioning device according to the present invention, at least one positioning element is designed and / or the vibration generator can be controlled so that at least one positioning element does not vibrate into the envelope curve of the stacking device at maximum deflection. In order not to hinder the transportation of repetitive components introduced perpendicularly to the stacking into the stacking device, the positioning element is not allowed to come into contact with the repetitive components even in a vibrating state. Therefore, the positioning element is designed by geometry and material so that when excited to vibrate, the positioning element does not reach the flight path of the vertically introduced repetitive components. Alternatively, the vibration generator can also be controlled so that the maximum deflection of the positioning element does not cause the positioning element to vibrate into the transportation path of the repetitive components.

[0020] According to another advantageous embodiment of the positioning device according to the invention, a plurality of positioning elements can be provided. Each positioning element can be set to vibration by a vibration generator, wherein the vibration generators can be individually controlled so that different vibration frequencies are generated by other vibration generators. As a result, the repetitive components can be aligned at a plurality of edge regions by means of the positioning elements, and the positioning can be flexibly adapted to the properties of the repetitive components by means of different frequencies.

[0021] According to another advantageous design of the positioning device according to the present invention, a plurality of elastic elements and / or a plurality of positioning elements can be provided, wherein at least one elastic element and / or positioning element has a different geometry from the other elastic elements or positioning elements. Thus, the impact of the introduced repeating components at multiple locations can be reduced and different geometries can be used for different edge regions of the repeating components in order to flexibly consider the characteristics of the repeating components. Thus, for the corresponding regions of the repeating components, the optimal flexibility of the elastic element can always be used. By replacing the positioning element or the elastic element with a corresponding element having a matching geometry or material, the matching of the repeating components with changed characteristics can be achieved cost-effectively.

[0022] According to another advantageous embodiment of the positioning device according to the invention, at least one positioning element and at least one vibration generator are fastened to a substrate, which is positioned in the height direction above the stacking device, wherein the substrate is designed to be detachable from the stacking device. The positioning element and the vibration generator are not connected to the stacking device, but are fixed to a substrate, which can be arranged above the stacking device. The possibility of detaching the substrate together with the positioning element and the vibration generator from the stacking device makes it possible to remove the stacking device from the stacking position so that further method steps in the formation of the cell stack, such as compacting the stack, can be performed, or so that the stacking device can be used as a workpiece carrier for the cell stacking in a further process.

[0023] According to another advantageous design of the positioning device according to the invention, a protective element for preventing the repeated component from warping is arranged in the gap between the stacking device and the substrate. As a result, the repeated component does not reach the gap between the substrate and the stacking device. For example, a plurality of protective elements can also be arranged next to the positioning element or the elastic element.

[0024] According to another advantageous embodiment of the positioning device according to the invention, at least one positioning element can be set to vibration by a vibration generator, so that the at least one positioning element vibrates at its natural frequency. Thus, relatively large vibration amplitudes can be generated by means of a small vibration generator, so that the structural space requirement of the vibration mechanism is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Some embodiments are described in detail below based on the accompanying drawings. The accompanying drawings show:

[0026] Figure 1 A side view showing a schematic diagram of a stacking device according to the invention,

[0027] Figure 2 A design scheme for a positioning device arranged above a stacking device is shown.

[0028] Figure 3 An embodiment for a base plate arranged above a stacking device is shown, in which the positioning elements are simultaneously designed as spring elements. DETAILED DESCRIPTION

[0029] Figure 1A side view of a schematic diagram of a manufacturing device 1 according to the present invention is shown. The first repeating component 2, in this example, the membrane electrode device of the fuel cell is arranged in a stack 10 in a silo-shaped repeating component providing device 3. The second repeating component 4, in this example, the bipolar plate for the fuel cell is provided in a stacking device 5 (a gravity silo in the embodiment shown). The first repeating component 2 is divided and transported to the stacking device 7 by means of a conveying device 6, here a negative pressure overhead conveyor belt, and is introduced laterally into the stacking device. The second repeating component 4 is transported separately from the stacking device 5 to the stacking device 7 from above. The first repeating component and the second repeating component 2, 4 are alternately stacked in the stacking device 7 to stack into a fuel cell stack. For this purpose, the stacking table 8 of the stacking device 7 is designed to be vertically movable and gradually moves downward during the stacking process. At the end of the stacking process, the stack 11 is taken out of the stacking device 7, and additional production steps are performed on the stack to manufacture a fuel cell stack. In principle, the device shown can also be used to produce battery cells, wherein separators and electrodes are stacked alternately on one another instead of membrane electrode assemblies and bipolar plates. It is also possible to stack prefabricated stacks, for example consisting of electrodes and separators, which together form a repeating component.

[0030] The alignment of the repeating component for placement in the stacking device is carried out in the positioning device 9. The positioning device 9 is arranged above the stacking device 7. In the positioning device 9, the first repeating component 2 transported from the conveyor device to the stacking device is braked and aligned relative to the stack 11.

[0031] Figure 2 A possible design scheme of the positioning device 9 is shown. The base plate 12 for being arranged above the stacking device 7 has a cutout 13, which is positioned above the stacking device 7 and whose size matches the size of the repeating components 2, 4 so that the repeating components 2, 4 can pass through. On the base plate 12, there is a spring element 14, which in this embodiment is implemented as a thin-sheet, curved damper composed of a material with elastic properties; for example, a material such as rubber or thermoplastic polyamide elastomer (TPA) can be used. If the repeating component 2 is introduced into the positioning device 9 laterally from the conveying device 6, the repeating component hits at least one of the spring elements 14 with its edge, and the spring element brakes the repeating component 2 due to its flexural properties without damaging the repeating component. When the repeating component 2 collides, the elastic sheet of the spring element 14 is squeezed so as to attenuate the collision of the repeating component 2.

[0032] Furthermore, a positioning element 15 is fastened to the base plate 12, which positioning element is designed as a thin plate in this case. Figure 3) is placed on the positioning elements 15, and the vibration generator sets the positioning elements 15 into vibration. If the repeating element 2 contacts one or more of the positioning elements 15, the repeating element is guided into the substrate toward the recess 13 by its vibration. By arranging the positioning elements 15 around the recess 13, the repeating element 2 is centered by the positioning elements 15 and placed on the stack 11.

[0033] Figure 3 Another possible design of the positioning device 9 is shown, in which the positioning element 15 simultaneously forms the elastic element 14. The positioning element 15 is fastened to the base plate 12 and is implemented as a thin plate in the present embodiment. The thin plate is flexible and thus suitable for braking the repetitive component 2. If the repetitive component 2 is introduced into the positioning device 9 laterally from the conveying device 6, the repetitive component hits at least one of the positioning elements / elastic elements 15 with an edge, and the repetitive component brakes the repetitive component 2 due to its elastic properties without damaging the repetitive component.

[0034] Furthermore, in this embodiment, each positioning element 15 is equipped with a vibration generator 16 which can be controlled so that it can set the positioning element 15 into vibration. By the vibration of the positioning element 15, the repetitive components are aligned and placed on the stack 11.

[0035] Furthermore, the positioning element 15 has a protective element 17 which is located in the gap between the stacking device 7 and the base plate 12 and prevents the repeating components 2 , 4 from warping in the gap.

Claims

1. A positioning device for positioning repetitive components to be placed on each other for stacking cells of battery cells or fuel cell cells, the positioning device comprising at least one elastic element, the at least one elastic element being designed so that when the repetitive component introduced into the positioning device is introduced into the positioning device transversely to the plane of the repetitive component with the edge of the introduced repetitive component hitting the at least one elastic element, the at least one elastic element brakes the repetitive component introduced into the positioning device, The at least one elastic element is further designed such that it can be elastically deformed in such a way that damage to the edge of the introduced repeating component can be avoided, and wherein the device further comprises at least one positioning element, The at least one positioning element can be set into vibration by means of a vibration generator so that at least one edge of an introduced repeating element is aligned relative to a corresponding edge of an already introduced repeating element. 2 . The positioning device according to claim 1 , wherein the at least one positioning element is also designed as the at least one elastic element.

3. The positioning device according to claim 1 or 2, characterized in that: The at least one positioning element is designed and / or the vibration generator is controllable in such a way that the at least one positioning element does not vibrate into the envelope curve of the stacking device according to claim 9 at maximum deflection.

4. A positioning device according to any one of the preceding claims, characterized in that A plurality of positioning elements are provided, which can each be set into vibration by a vibration generator, wherein the vibration generator can be individually controlled in order to generate a vibration frequency that is different from that of the other vibration generators.

5. A positioning device according to any one of the preceding claims, characterized in that A plurality of elastic elements and / or a plurality of positioning elements are provided, wherein at least one elastic element and / or positioning element has a different geometry than the other elastic elements or positioning elements.

6. A positioning device according to any one of the preceding claims, characterized in that The at least one positioning element and the at least one vibration generator are fastened to a base plate which is positioned in height direction above the stacking device according to claim 9 , wherein the base plate is designed to be detachable from the stacking device.

7. A positioning device according to any one of the preceding claims, characterized in that A protection element for preventing warping of repeated components is provided in a gap between the stacking device and the substrate.

8. A positioning device according to any one of the preceding claims, characterized in that The at least one positioning element is set into vibration by a vibration generator, so that the at least one positioning element vibrates at its natural frequency.

9. A stacking device for forming a cell stack for battery cells or fuel cell cells by repeated components to be placed on each other, the stacking device comprising at least one positioning device and a receiving portion according to any one of the above claims, the receiving portion having a supporting device movable in the height direction, the supporting device being used to support and adjust the height of the cell stack during stacking.

10. A stacking method for forming a cell stack for a battery cell or a fuel cell from a plurality of repeating components to be placed on each other, the stacking method comprising: a) providing a stacking device according to claim 9, b) Drop the duplicate parts, c) centering the repeating element by means of vibrations of the at least one positioning element in order to align the repeating element relative to an edge of an already placed repeating element, e) Repeating steps a) to c) with further repeating components, in order to thereby form the cell stack.

11. The stacking method according to claim 10, characterized in that The following steps are provided to be performed after step c): d) moving the supporting device downwards, In step e), steps a) to d) are repeated using the further repeating element.

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