Method for producing accumulators and corresponding stacking device for producing accumulators

Abstract

The invention relates to a method for producing accumulators which each have at least one cell stack (6), wherein to produce the cell stack (6), individual sheets (4) are stacked by means of a stacking device (2) in that the individual sheets (4) are fed one after the other by means of a conveying line (8) of the stacking device (2) to a stacking wheel arrangement (12) of the stacking device (2), wherein the stacking wheel arrangement (12) has two stacking wheels (28) which are arranged in two planes one above the other, in that a predefined number of successive individual sheets (4) are fed to one of the two stacking wheels (28), wherein the predefined number corresponds to the number of individual sheets (4) in a finished cell stack (6), and in that a plurality of the individual sheets (4) following the predefined number of individual sheets (4) are fed to the other of the two stacking wheels (28).

Description

[0001] Description

[0002] METHOD FOR PRODUCING ACCUMULATIVE BATTERIES AND CORRESPONDING STACKING DEVICE FOR PRODUCING ACCUMULATIVE BATTERIES

[0003] The invention relates to a method for producing accumulators. Furthermore, the invention relates to a stacking device for producing accumulators.

[0004] Batteries are widely used to store electrical energy. In some applications, they are composed of multiple battery cells and are also used in the automotive sector. Here, the batteries serve, for example, as so-called drive or traction batteries for powering hybrid or electric vehicles.

[0005] Lithium-ion batteries, i.e., batteries made of lithium-ion cells, are currently of particular interest. A variety of designs are known regarding their precise construction. The production of lithium-ion cells is outlined, for example, in "Heimes, Heiner Hans; Kampker, Achim; Lienemann, Christoph; Locke, Marc; Offermanns, Christian; Michaelis, Sarah; Rahimzei, Ehsan (2018): Production process of a lithium-ion battery cell, Frankfurt am Main, PEM of RWTH Aachen University and VDMA Eigendruck."

[0006] The invention is based on the object of providing an advantageous method for producing accumulators. Furthermore, the invention is based on the object of providing an advantageous stacking device for producing accumulators. This object is achieved by a method having the features of patent claim 1 and by a stacking device having the features of patent claim 10. The advantages and preferred embodiments cited with regard to the method are also transferable to the stacking device, and vice versa. Advantageous embodiments with expedient further developments of the invention are specified in the dependent claims.

[0007] The method according to the invention is designed for the production of rechargeable batteries. A corresponding rechargeable battery typically has a number of rechargeable battery cells, wherein such a rechargeable battery cell usually has a cell housing or a cell enclosure. Depending on the application, such a rechargeable battery is thus then formed, for example, by a single rechargeable battery cell. Typically, however, a corresponding rechargeable battery has several such rechargeable battery cells and generally forms a battery or a battery module. A corresponding battery, in turn, typically has a battery housing, and a corresponding battery module usually has a module housing or a carrier unit for rechargeable battery cells. If the rechargeable battery is designed as a battery, in some cases it has a number of the aforementioned battery modules, i.e. at least one such battery module and typically several.

[0008] Independently of this, each accumulator manufactured using the method has at least one cell stack formed by stacked individual sheets. If the accumulator is constructed from the aforementioned accumulator cells, each accumulator cell typically has such a cell stack, in particular exactly one. Furthermore, each of these accumulator cells is then preferably designed as a so-called pouch cell.

[0009] Furthermore, the cell stack expediently forms a so-called electrode stack. This means that the cell stack contains layers or stacks of electrode materials. Furthermore, a corresponding battery is preferably designed as a lithium-ion battery. Therefore, the layers or stacks in the cell stack typically comprise an anode material, a separator material, and a cathode material.

[0010] Suitable single sheets for the production of a corresponding cell stack for a lithium-ion battery and a possible process for producing such single sheets are described, for example, in "Heimes, Heiner Hans; Kampker, Achim; Lienemann, Christoph; Locke, Marc; Offermanns, Christian; Michaelis, Sarah; Rahimzei, Ehsan (2018): Production process of a lithium-ion battery cell, Frankfurt am Main, PEM of RWTH Aachen University and VDMA Eigendruck." The corresponding single sheets are referred to here as "sheets."

[0011] In this specific example, three different sheets are manufactured: anode sheets a, which comprise an anode material, separator sheets b, which comprise a separator material, and cathode sheets c, which comprise a cathode material. To produce a corresponding cell stack, these individual sheets are then conveniently stacked in a sequence abcabc and so on.

[0012] An alternative variant uses single sheets, known as monocells. Such monocell sheets typically comprise an anode material, a cathode material, and a separator material in between.

[0013] Independently of this, the individual sheets have a length, a width, and a thickness. A typical thickness value lies in the range of 0.05 mm to 2.5 mm, and especially in the range of 0.1 mm to 1.5 mm. For length and width, values ​​that are at least a factor of 5 or at least a factor of 10 larger are common.

[0014] Corresponding individual sheets are then stacked into cell stacks during the execution of the method, i.e., the method according to the invention. The method for producing accumulators thus comprises at least one stacking step, in which the individual sheets are stacked. This stacking step is carried out using the stacking device according to the invention, and in particular, is fully automated.

[0015] The stacking device, in turn, i.e., the stacking device according to the invention, is designed for producing the previously described accumulators using the method according to the invention and, in particular, for automatically executing the stacking part of the method in at least one operating mode. The automatic execution is typically controlled by a control unit of the stacking device. Independently of this, the stacking device, hereinafter also referred to as the device for short, comprises a conveyor line and a stacking wheel arrangement.

[0016] In the stacking wheel arrangement, two stacking wheels are arranged in two superimposed levels. "Superimposed" means that the two levels are vertically offset from each other relative to the Earth system. Furthermore, depending on the design variant, the two stacking readers are arranged one above the other or, in addition, are horizontally offset from each other relative to the Earth system.

[0017] In any case, during the stacking process, the single sheets are fed one after the other to the stacking wheel assembly via the conveyor line. A predetermined number of consecutive single sheets is then fed to one of the two stacking wheels, and subsequently, several of the single sheets following the predetermined number are fed to the other of the two stacking wheels. The predetermined number of single sheets then corresponds to the intended number of single sheets in a finished cell stack.

[0018] Furthermore, the single sheets are typically fed continuously to the stacking wheel assembly. This means that the conveyor line typically transports the single sheets at a constant speed, and the speed is preferably not changed, even when switching from feeding single sheets to one of the stacking wheels to feeding single sheets to the other of the stacking wheels. This essentially ensures a continuous flow of single sheets to the stacking wheel assembly. In the stacking wheel assembly, the two stacking wheels are then used alternately, particularly to stack single sheets into cell stacks.

[0019] Furthermore, the individual sheets fed via the conveyor line are expediently already arranged on the conveyor line in a predetermined sequence, at least if different individual sheets are to be stacked, and / or the individual sheets are aligned and oriented in a predetermined manner, i.e. in particular they lie on the conveyor line with a predetermined side.

[0020] It is further advantageous if the stacking device has a distribution unit which is positioned between the conveyor line and the stacking wheel arrangement. The corresponding distribution unit has two branches, namely a first branch and a second branch, wherein each of the two stacking wheels, namely the first stacking wheel and the second stacking wheel, is assigned a branch, i.e. the first branch to the first stacking wheel and the second branch to the second stacking wheel. In the course of carrying out the method, individual sheets are then fed to each of the two stacking wheels via one of the two branches, wherein the individual sheets are preferably conveyed either into the first branch or into the second branch depending on the position of a switch in the distribution unit.

[0021] If the distribution unit has a switch mentioned above, this is preferably implemented as a distribution roller. The distribution roller is preferably vertically displaceable relative to the earth system, or it is close enough to be vertically displaceable. "Close enough to be close enough" means that the actual direction preferably deviates from the vertical direction by no more than 40°, more preferably no more than 25°, and especially no more than 15°.

[0022] Furthermore, the distribution roller is preferably movable between two vertical positions, namely between a first position and a second position. In the first position, the single sheets fed to the switch are transported via the switch into the first branch, and in the second position, the single sheets fed to the switch are transported via the switch into the second branch.

[0023] According to an advantageous development, the distribution roller is supplemented by a pair of rollers, which are also part of the switch. This pair of rollers is then formed by two rollers, which are typically arranged offset from one another in the aforementioned vertical direction.

[0024] Furthermore, at least one of these two rollers is preferably driven, so that the two rollers form a so-called conveyor roller pair. This means that these rollers rotate in opposite directions during operation, thereby conveying the individual sheets fed in, so that they are guided between the rollers.

[0025] In the switch, the distribution roller also preferably forms such a conveyor roller pair, either together with one roller of the roller pair or together with the other roller of the roller pair, depending on the vertical position of the distribution roller.

[0026] It is also expedient if the first branch of the distribution unit has at least one pair of conveyor rollers for conveying the individual sheets. Other typical designs include the first branch having at least two conveyor roller pairs, namely a conveyor roller pair of a first type and a conveyor roller pair of a second type. The two types differ, for example, in the diameter of the rollers that form the respective conveyor roller pairs.

[0027] It is also advantageous if the first branch has at least one pair of guide plates, with two guide plates, in particular arranged one above the other. The corresponding guide plates serve to guide the individual sheets during conveyance via the first branch. This means that the individual sheets conveyed via the first branch are guided between the two guide plates of the guide plate pair. In some applications, the previously described guide plates also have openings, in particular slots. To convey the individual sheets, projections on the rollers of one of the aforementioned conveyor roller pairs then preferably engage through the openings, so that the conveyance of the individual sheets is accomplished with the aid of the projections.

[0028] Such projections are, for example, ring-shaped. The ring-shaped projections of each roller are then arranged around a roller axis and spaced apart in a row along the axis. The profile of the rollers thus reveals a rectangular toothing.

[0029] Depending on the application, the second branch of the distribution unit has none, one or more of the previously described features of the first branch of the distribution unit.

[0030] According to at least one embodiment variant, the rollers of the previously described switch also have such projections. In the case of the distributor roller, however, the annular projections are preferably arranged, viewed along an axis of the distributor roller, alternately offset in a transverse direction transverse to the axis and in a direction opposite to the transverse direction.

[0031] In an advantageous development, the distribution roller is also provided with a guide plate having a V-shape formed by two legs. Both legs typically have openings, and the distribution roller is conveniently arranged between the two legs.

[0032] Furthermore, one of the stacking wheels, namely the first stacking wheel, has an axle. Another advantageous embodiment is one in which the first stacking wheel is designed as a driven stacking wheel and thus rotates in a direction of rotation around the axis during operation. Independently of this, the first stacking wheel preferably has a plurality of fingers which are arranged in a row at a distance from one another along the axis. In addition, the first stacking wheel preferably has a plurality of such rows which are distributed around the axis. Typical embodiments here are those with more than two fingers per row and more than ten rows. A single sheet fed to the first stacking wheel is then typically inserted into a space between two rows which follow one another in the circumferential direction or in the aforementioned direction of rotation.

[0033] Furthermore, the fingers are preferably curved. In this case, the fingers are bent, in particular, opposite to the aforementioned direction of rotation.

[0034] The other of the two stacking wheels, namely the second stacking wheel, has none, one, or more of the previously described features of the first stacking wheel, depending on the design variant. Preferably, the stacking wheels of the stacking wheel arrangement are of similar design.

[0035] It is also useful if each of the stacking wheels is assigned a stacking table, on which individual sheets are stacked into cell stacks using the respective stacking wheel. It is then preferable to assign a common gripper of the stacking device to the stacking tables, which is used to remove the finished cell stacks from the stacking tables.

[0036] Depending on the design variant, the finished cell stacks are also turned with the gripper.

[0037] Regardless of this, it is advantageous if the finished stacked cell stacks are fed into a continuous furnace using the gripper. In the continuous furnace, the finished stacked cell stacks are then subjected to heat treatment. During this heat treatment, pressure is preferably exerted on the stacks, typically in the stacking direction. In this case, the continuous furnace essentially performs a hot pressing process. The advantages and refinements described in connection with the method can also be applied to the stacking device, and vice versa.

[0038] In summary, the idea underlying the inventive method and the inventive stacking device can be formulated as follows: To produce a rechargeable battery, monocells must be stacked. Stacking wheels are useful for this. Since the pack is complete after a certain number of monocells, the inflow of monocells is then redirected to a different path and thus to a different stacker / stacker wheel. A gripping mechanism then generates a continuous flow of packs. For this purpose, two stackers are alternately loaded with the desired number of monocells using a tandem principle. A manipulator designed as a gripper then collects the packs from the stacker that is currently finishing its work. A double conveyor belt with heated belts acts as a continuous oven for transporting and laminating the pack.

[0039] This offers several advantages: Taped stacks are no longer required to temporarily secure them, as they are secured immediately after stacking in the oven. Continuous clamping is provided. The packs are ultimately positioned the right way round after the cells have been temporarily turned over during the stacking process. The two material streams temporarily generated by the tandem operation are ultimately combined into one. The exposure time to the temperature required for lamination and the number of cells per stack determine the length of the continuous oven.

[0040] Further advantages, features, and details of the invention will become apparent from the claims, the following description of preferred embodiments, and the schematic drawings, in which:

[0041] Fig. 1 shows a stacking device comprising a conveyor line, a distribution unit, a stacking wheel arrangement and a gripper, Fig. 2 shows an enlarged view of a lower branch of the distribution unit,

[0042] Fig. 3 enlarges a pair of rollers of the distribution unit,

[0043] Fig. 4 shows an enlarged view of a switch of the distribution unit,

[0044] Fig. 5 enlarges a stacking wheel of the stacking arrangement,

[0045] Fig. 6 shows two gripping jaws of the gripper in an enlarged view, and

[0046] Fig. 7 a single sheet for a cell stack of an accumulator.

[0047] Corresponding parts are provided with the same reference numerals in all figures.

[0048] A stacking device 2, described below as an example, serves to automatically execute a stacking process component in which individual sheets 4 are stacked into cell stacks 6. The stacking process component is part of a process for producing accumulators (not shown), namely lithium-ion accumulators, each accumulator having at least one such cell stack 6. The automatic execution is typically controlled by a control unit (not shown) of the stacking device 2.

[0049] The stacking device 2 now has a conveyor line 8, a distribution unit 10, a stacking wheel arrangement 12, and preferably also a gripper 14. Furthermore, the stacking device 2 preferably has a continuous furnace 16. A variant with a gripper 14, namely with a first gripper 14, and with a continuous furnace 16 is shown in Fig. 1. Figs. 2 to 6 show various sections of Fig. 1 in enlarged form.

[0050] During operation of the stacking device 2 and thus during the execution of the stacking process part, the individual sheets 4 are continuously fed to the distribution unit 10 via the conveyor line 8. In the case of the embodiment according to Fig. 1, the conveyor line 8 is designed as a simple conveyor belt that transports the individual sheets 4 in a conveying direction.

[0051] By way of example, all supplied single sheets 4 are designed in the same way.

[0052] Fig. 7 shows an example of such a single sheet 4. It is designed as a so-called monocell and has a layer of an anode material 18, a layer of a cathode material 20 and an intermediate layer of a separator material 22. In addition, the single sheet 4 has two electrically conductive conductor foils 24, one of the conductor foils 24 being in contact with the anode material 18 and the other with the cathode material 20. Both conductor foils 24 each form a so-called conductor tab 26, the two conductor tabs 26 protruding on opposite sides of the single sheet 4. In Fig. 7, only the conductor tab 26 of the conductor foil 24 protruding from the plane of the drawing on the anode material 18 is visible.

[0053] On the conveyor belt shown in Fig. 1, several of these single sheets 4 are now already arranged one behind the other in the conveying direction. These single sheets 4 are all aligned and oriented in the same way. In this manner, during operation of the stacking device 2, the single sheets 4 are then fed to the distribution unit 10. The conveyor line 8 typically transports the single sheets 4 at a predetermined speed, which is preferably kept constant at least over a period of time during which several cell stacks 6 are stacked.

[0054] The cell stacks 6 are further stacked by means of the stacking wheel assembly 12 of the stacking device 2, which for this purpose has two stacking wheels 28. To distribute the single sheets 4 fed via the conveyor line 8 to the stacking wheels 28, the distribution unit 10 is positioned between the conveyor line 8 and the stacking wheel assembly 12, with the distribution unit 10 having a branch 30 for each stacking wheel 28. Each stacking wheel 28 is thus assigned a branch 30, via which single sheets 4 can be fed to the corresponding stacking wheel 28.

[0055] The stacking wheels 28 are further arranged in two superimposed planes. This means that the stacking wheels 28 are offset from one another in the vertical direction with respect to the Earth system, or at least to a good approximation in the vertical direction. In this case, a good approximation means that the actual direction preferably deviates from the vertical direction by no more than 40°, more preferably no more than 25°, and in particular no more than 15°. In contrast, in the horizontal direction with respect to the Earth system, or at least to a good approximation in the horizontal direction, the stacking wheels 28 are preferably not offset. In this case, a good approximation means that the actual direction preferably deviates from the horizontal direction by no more than 40°, more preferably no more than 25°, and in particular no more than 15°.

[0056] Preferably, the stacking wheels 28 are therefore arranged one above the other, as indicated in Fig. 1. Therefore, one of the stacking wheels 28, namely the one shown at the top in Fig. 1, is referred to below as the upper stacking wheel 28, and the other stacking wheel 28, namely the one shown at the bottom in Fig. 1, is referred to as the lower stacking wheel 28. The branch 30 assigned to the upper stacking wheel 28 is additionally referred to as the upper branch 30, and the branch 30 assigned to the lower stacking wheel 28 is referred to as the lower branch 30.

[0057] In order to enable distribution of the single sheets 4 between the two branches 30, the distribution unit 10 typically has a switch. The switch is preferably designed as a distribution roller 32, as shown in Fig. 4. The distribution roller 32 is adjustable in the aforementioned vertical direction, or at least to a good approximation in the vertical direction, and in particular is displaceable between two vertical positions. In the upper vertical position, the single sheets 4 fed to the switch are then conveyed via the switch into the upper branch 30, and in the lower vertical position, the single sheets 4 fed to the switch are conveyed via the switch into the lower branch 30.

[0058] In the exemplary embodiment, the distribution roller 32 is supplemented by a pair of rollers, which are also part of the switch. This pair of rollers is formed by two rollers 34 arranged one above the other. Thus, the pair of rollers comprises an upper roller 34 and a lower roller 34.

[0059] In addition, at least one of the two rollers 34 is driven, forming a so-called conveyor roller pair. This means that these rollers 34 rotate in opposite directions during operation, thereby conveying the supplied single sheets 4, so that they are guided between the rollers 34.

[0060] In the switch, the distribution roller 32 also expediently forms such a conveyor roller pair, depending on the vertical position of the distribution roller 32, either together with the upper roller 34 of the roller pair or together with the lower roller 34 of the roller pair.

[0061] In addition, the aforementioned branches 30 typically each have roller pairs configured as conveyor roller pairs. In the embodiment shown in Fig. 1, each branch 30 has a roller pair with rollers 36 of a first type and a roller pair with rollers 38 of a second type. The two types differ in the diameter of the rollers 36, 38.

[0062] Furthermore, a preferred embodiment of the stacking device 2 is one in which the distribution unit 10, as in the embodiment variant according to Fig. 1, has at least two guide plates 40, which are arranged in particular one above the other and thus form a guide plate pair. In this case, the individual sheets 4 are then expediently guided between the guide plates 40 of the guide plate pair.

[0063] In the embodiment according to Fig. 1, the guide plates 40 also have openings 42, in particular slots. This is at least indicated in Fig. 3. To convey the individual sheets 4, projections 44 on the rollers 36, 38 then engage through the openings 42, so that the conveyance of the individual sheets 4 is accomplished with the aid of the projections 44.

[0064] These projections 44 are annular in the embodiment according to Fig. 1. The projections 44 of each roller 36, 38 are guided around an axis 46, 48 of the roller and, viewed along the axis 46, 48, are arranged in a row at a distance. In profile, the rollers 36, 38 thus have rectangular teeth. According to the embodiment variant according to Fig. 1, the rollers of the previously described switch also have such projections 44. In the case of the distributor roller 32, however, the annular projections 44 are arranged alternately offset along an axis 50 of the distributor roller 32, once in a transverse direction transverse to the axis 50, and once in the opposite transverse direction. This can be seen in Fig. 4.

[0065] In addition, the distribution roller 32 in the embodiment shown in Fig. 1 is combined with a guide plate 52, which has a V-shape formed by two legs. Both legs have openings (not shown in detail) similar to the openings 42, and the distribution roller 32 is positioned between the two legs. Individual sheets 4 are then guided via the upper leg into the upper branch 30 and via the lower leg into the lower branch 30.

[0066] The stacking wheels 28 of the stacking wheel arrangement 12 are further preferably of identical design. In this case, it is typically the case for each stacking wheel 28 that it is designed as a driven stacking wheel 28 and thus rotates in a direction of rotation 54 about an axis 56 during operation. Furthermore, it preferably has a plurality of fingers 58 which are arranged in a row at a distance from one another along the axis 56. In addition, this stacking wheel 28 preferably has a plurality of such rows which are distributed around the axis 56. Typical designs here are those with more than two fingers 58 per row and more than ten rows. A stacking wheel 28 designed in this way is shown in Fig. 5. A fed single sheet 4 is then fed into a space between two rows following one another in the direction of rotation.

[0067] Furthermore, the fingers 58 are preferably curved, as is the case in the exemplary embodiment according to Fig. 1. The fingers 58 are then preferably bent counter to the direction of rotation 54. It is also expedient if each stacking wheel 28 of the stacking wheel arrangement 12 is assigned a stacking table 60, on which the individual sheets 4 fed to the corresponding stacking wheel 28 are stacked into cell stacks 6.

[0068] The stacking device 2 is also preferably designed and configured such that the two stacking wheels 28 of the stacking wheel arrangement 12 alternately stack single sheets 4 into cell stacks 6. This means that, first, sufficient single sheets 4 for a cell stack 6 are conveyed into one of the branches 30. Then, the switch position of the switch of the distribution unit 10 is changed, i.e., in particular, the vertical position of the distribution roller 32 is changed, so that the subsequent single sheets are fed to the other branch 30. As a result, cell stacks 6 are then also alternately stacked on the stacking tables 60.

[0069] Furthermore, the stacking device 2 preferably has the previously mentioned first gripper 14, as in the exemplary embodiment according to Fig. 1 . This first gripper 14 is then typically assigned to both stacking tables 60 of the stacking wheel arrangement 12, so that the first gripper 14 removes fully stacked cell stacks 6 from both stacking tables 60. If the stacking device 2, as preferred, also has the previously mentioned continuous furnace 16, the first gripper expediently feeds the fully stacked cell stacks 6 to the continuous furnace 16. In the course of this, the cell stacks 6 are turned according to at least one embodiment variant.

[0070] Various designs are suitable for the first gripper 14. In the embodiment shown in Fig. 1, the first gripper 14 has two gripping jaws 62 that can be moved toward and away from each other, thus enabling a sort of gripping action. The two gripping jaws 62 are further connected via a telescopic arm 64 to a rotational axis 66, about which the telescopic arm 64 can rotate. In the embodiment shown in Fig. 1, the rotational axis 66 is mounted vertically displaceably on a rail 68.

[0071] In the embodiment according to Fig. 1, the two gripping jaws 62 are still of identical design and each have a shape reminiscent of a comb. To form such a comb shape, several parallel strips 70 are arranged next to one another. This can be seen in Fig. 6. To grip a fully stacked cell stack 6 from one of the stacking tables 60, the strips 70 of the lower gripping jaw 62 are then inserted into suitably designed grooves 72 on the stacking table 60, so that the corresponding strips 70 are positioned below the lowest single sheet 4 before gripping the cell stack 6. The grooves 72 are clearly visible in Fig. 5.

[0072] As already explained above, the first gripper 14 is preferably used to feed finished stacked cell stacks 6 to the aforementioned continuous furnace 16. In this case, at least the continuous furnace 16 in the embodiment according to Fig. 1 has a further gripper 74, namely a second gripper 74. The second gripper 74 is formed by two gripper jaws 76. Each of these gripper jaws 76 is designed like a simple conveyor belt with two deflection rollers, but instead of a single wide belt, several narrow belts 78 are stretched between the two deflection rollers and arranged next to one another. As shown in Fig. 6. A gap is left between each belt 78 so that the strips 70 of the gripper jaws 62 of the first gripper 14 can be positioned between the belts 78.In addition, the two gripping jaws 76 of the second gripper 74 are each pivotally mounted about an axis so that they can be moved like the two jaws of a pair of pliers.

[0073] According to the embodiment shown in Fig. 1, a heatable conveyor line 80 of the continuous furnace 16 is connected to the second gripper 74 of the continuous furnace 16. In the exemplary embodiment, this conveyor line is formed by two conveyor belts arranged one above the other, between which the cell stacks 6 are guided. Pressure is preferably exerted by the two conveyor belts on the cell stacks 6 as they pass through, acting in the vertical direction and counter to the vertical direction.

[0074] 2 stacking device

[0075] 4 single sheets

[0076] 6 cell stacks

[0077] 8 Conveyor Road

[0078] 10 Distribution unit

[0079] 12 Stacking wheel arrangement

[0080] 14 first gripper

[0081] 16 continuous furnace

[0082] 18 Anode material

[0083] 20 Cathode material

[0084] 22 Separator material

[0085] 24 Conductor foil

[0086] 26 arrester flags

[0087] 28 Stacking wheel

[0088] 30 branches

[0089] 32 Distributor roller

[0090] 34 roller

[0091] 36 rollers

[0092] 38 roller

[0093] 40 baffle

[0094] 42 Breakthrough

[0095] 44 lead

[0096] 46 Axis

[0097] 48 Axis

[0098] 50 axle

[0099] 52 guide plate

[0100] 54 Direction of rotation

[0101] 56 Axis

[0102] 58 fingers

[0103] 60 stacking table

[0104] 62 gripping jaw 64 telescopic arm

[0105] 66 Rotation axis

[0106] 68 rail

[0107] 70 strip 72 groove

[0108] 74 second gripper

[0109] 76 gripping jaw

[0110] 78 belts

[0111] 80 Conveyor Road

Claims

Patent claims 1 . A method for producing accumulators, each of which has at least one cell stack (6), wherein, for the production of the cell stacks (6), individual sheets (4) are stacked by means of a stacking device (2) by - the individual sheets (4) are fed successively to a stacking wheel arrangement (12) of the stacking device (2) by means of a conveyor line (8), the stacking wheel arrangement (12) having two stacking wheels (28) arranged in two superimposed planes, - a predetermined number of consecutive single sheets (4) is fed to one of the two stacking wheels (28), the predetermined number corresponding to the number of single sheets (4) in a finished cell stack (6), and - several of the single sheets (4) following the specified number of single sheets (4) are fed to the other of the two stacking wheels (28).

2. Method according to claim 1, wherein the two stacking wheels (28) alternately stack individual sheets (4) to form cell stacks (6).

3. The method according to claim 1 or 2, wherein - the stacking device (2) has a distribution unit (10) which is positioned between the conveyor line (8) and the stacking wheel arrangement (12), - the distribution unit (10) has two branches (30), namely a first branch (30) and a second branch (30), - single sheets (4) are fed to each of the two stacking wheels (28) via one of the two branches (30) and the individual sheets (4) are fed either to the first branch (30) or to the second branch (30) depending on a vertical position of a distribution roller (32).

4. Method according to claim 3, wherein the first branch (30) has a pair of rollers (36, 38) by means of which individual sheets (4) are conveyed over the first branch (30).

5. The method according to claim 4, wherein - the first branch (30) has a pair of guide plates with two guide plates (40) arranged one above the other, between which the individual sheets (4) conveyed via the first branch (30) are guided, - each of the rollers (36) of the roller pair is designed as a roller (36) with an axis (46) and with annular projections (44), - the annular projections (44) are formed running around the axis (46) and are arranged in a row at a distance from one another, viewed along the axis (46), and - the individual sheets (4) guided over the first branch (30) are conveyed by means of the projections (44) of the rollers (36), which for this purpose reach through openings (42) in the guide plates (40) of the guide plate pair.

6. Method according to one of claims 1 to 5, wherein one of the two stacking wheels (28) has an axis (46) and a plurality of fingers (58) arranged distributed around the axis (46), and wherein a single sheet (4) fed to this stacking wheel (28) is guided into a space between two fingers (58) following one another in a direction of rotation (54).

7. Method according to one of claims 1 to 6, wherein each of the stacking wheels (28) is assigned a stacking table (60) of the stacking wheel arrangement (12), on which the respective stacking wheel (28) Single sheets (4) are stacked to form cell stacks (6), and wherein the stacking tables (60) are assigned a common gripper (14) of the stacking device (2), with which the fully stacked cell stacks (6) are removed from the stacking tables (60).

8. The method according to claim 7, wherein the finished cell stacks (6) are turned with the gripper (14).

9. The method according to claim 7 or 8, wherein the finished cell stacks (6) are fed to a continuous furnace (16) with the gripper (14).

10. Stacking device (2) for producing accumulators by means of a method according to one of the preceding claims.

Images