Method and device for transporting flat electrode elements

Abstract

The invention relates to a device (5) for transporting and optionally stacking flat electrode elements (1), said device being designed to transport the flat electrode elements individually one after the other along the transport path (10). The device has a spacing increasing device (12) which is arranged along the transport path of the flat electrode elements, e.g., upstream of a stacking device (17), and is designed to increase the spacing (a) of the flat electrode elements, in particular up to a processing spacing (A), by accelerating the flat electrode elements in order to facilitate access to individual flat electrode elements of the flat electrode elements.

Description

[0001] Method and device for transporting flat electrode elements

[0002] The invention relates to a method and a device for transporting and, if necessary, stacking flat electrode elements.

[0003] It is known to stack flat electrode elements for the production of electrochemical energy storage devices, such as lithium-ion batteries, or energy converters, such as fuel cells. Electrode elements are stacked, particularly in the production of pouch cells, a widely used type of lithium-ion accumulator. The smallest unit of a lithium-ion cell typically consists of two electrode elements and a separator that separates the electrode elements from one another. In a production line for electrochemical energy storage devices, e.g., for electrically powered vehicles, a large number of such units, each separated by a further separator, are placed in a casing, which is then filled with an ion-conductive electrolyte and sealed.

[0004] Known methods for stacking electrode elements rely on a robot's gripper arm, which grasps and positions the electrode elements. Furthermore, it has been proposed to use a rotating stacker wheel for stack formation, with which the electrode elements are placed on an electrode stack. WO 2020 / 212316 A1 describes a method for producing an electrode stack from anodes and cathodes for a lithium-ion battery of an electrically powered motor vehicle. The anodes and cathodes are conveyed into compartments of a rotating stacker wheel, and the anodes and cathodes held in the compartments are conveyed to a stack holder based on the rotation of the stacker wheel.

[0005] In a manufacturing facility for electrode elements, these are typically produced by separating them from a long web of material and are thus arranged at a small distance from one another, created during the separation process. This separation distance is typically in the millimeter range or less. Due to the small distance between them, the electrode elements must be transported at a relatively low transport speed to allow mechanical access to each of the flat electrode elements, e.g., so that the individual flat electrode elements can be reliably separated from one another and inserted into the individual compartments of a rotating forklift wheel.It may even be necessary to slow down or temporarily stop the transport of the respective flat electrode element in front of the rotating forklift wheel in order to reliably insert the flat electrode elements into the forklift wheel separately from one another.

[0006] If the flat electrode elements - for separate insertion into different compartments of the forklift wheel - are transported at a relatively low transport speed, it has been shown that the flat electrode elements are not reliably transported into the forklift wheel.

[0007] An object of the invention is to provide a method and a device which makes it possible to more easily separate the individual flat electrode elements transported one after the other during their transport, which, for example, makes it possible to transport the successive flat electrode elements reliably and separately from one another into compartments of a forklift wheel.

[0008] This object is achieved according to the invention by a method and a device according to the independent claims. Advantageous embodiments of the invention are the subject of the dependent claims. Prior to the invention, it was recognized that individual mechanical access to each of the flat electrode elements transported one behind the other, e.g., to separate them from one another, is easier if the distance between the individual electrode elements is greater.

[0009] The invention therefore proposes increasing the spacing between the planar electrode elements transported one behind the other or following one another. The increased spacing between the planar electrode elements transported one behind the other in a stream of planar electrode elements makes it easier to mechanically separate the planar electrode elements from one another during transport. This is because with an increased spacing, it is easier to mechanically influence one of the planar electrode elements of the stream without affecting the preceding or following electrode element. After the spacing has been increased, the planar electrode elements of the stream can be transported to different destinations as needed, e.g., to different transport branches or to different compartments of a forklift wheel.

[0010] For example, the flat electrode elements transported one after the other can be sorted more easily due to the increased spacing, e.g., into different transport branches, into which the transport path of the flat electrode elements branches after the spacing enlargement device. For example, one or more of the flat electrode elements can be more easily sorted out from the stream of flat electrode elements.

[0011] The device according to the invention comprises a transport device designed to individually transport the planar electrode elements along a transport path, and a distance-increasing device for increasing their distance from one another. The planar electrode elements are accelerated by the distance-increasing device, i.e., the transport speed of the planar electrode elements after the distance-increasing device is increased compared to the transport speed of the planar electrode elements before the distance-increasing device. In comparison to a distance increase by temporarily braking the current, e.g.by decelerating the subsequent flat electrode element or by stop-and-go operation of the transport device, the accelerating increase in distance has the advantage that a braking reaction on the manufacturing device for electrode elements upstream of the device according to the invention, which provides the electrode elements, is thereby avoided.

[0012] In particular, the invention proposes increasing the distance between the successive flat electrode elements before stacking the flat electrode elements or before a stacking wheel used for stacking. Due to the increased distance, the individual flat electrode elements can then be transported more easily, separately from one another, into different compartments of the stacking wheel. The increased distance ensures that - even with the increased transport speed between the successive electrode elements - a sufficiently large time window is available for the separate insertion of the successive electrode elements into the various compartments of the stacking wheel. Prior to the invention, it was also recognized that the insertion of the flat electrode elements into the stacking wheel works more reliably if they are inserted into the stacking wheel with greater kinetic energy.The increased transport speed due to acceleration allows for a more reliable transport of the electrode elements into the forklift wheel. This is because the flat electrode elements then have greater kinetic energy, i.e., sufficient momentum to slide from the transport device that transports the electrode elements to the forklift wheel into the forklift wheel. Compared to the kinetic energy of the flat electrode elements, their weight or friction then plays a lesser role, i.e., it has a less disruptive effect on the movement of the flat electrode elements as they slide into the forklift wheel.

[0013] Preferably, the transport speed of the flat electrode elements in the device according to the invention is increased to a higher transport speed that is higher than at the entrance to the device. For example, this higher transport speed is maintained up to the stacking device and the transport of the respective electrode element into the stacker wheel. In particular, the transport speed of the flat electrode elements when transporting into the stacker wheel is preferably at least a factor of 1.1, particularly preferably at least a factor of 1.5, higher than the transport speed of the flat electrode elements at the exit of the machine that is upstream of the device according to the invention, e.g. at the exit of the manufacturing device for electrode elements that is upstream of the device according to the invention in a production plant for electrode stacks.For example, the transport speed of the flat electrode elements when transporting them into the forklift wheel is at least 0.3 m / s, preferably at least 1 m / s.

[0014] As a result of the increase in distance, the leading edge-to-leading edge distance of the successive flat electrode elements also increases. Preferably, the increase in the leading edge-to-leading edge distance of the successive flat electrode elements corresponds approximately to the increase in the transport speed, so that the transport rate (number of electrode elements / second) remains the same as before the increase in distance, e.g., the same as the electrode element output rate of the machine upstream of the device according to the invention in the production plant. In the following, the term flat electrode element is understood to mean an electrode element which has a much larger area compared to its thickness, e.g., whose length and width are at least 10 times the thickness.For simplicity, the term "electrode element" was sometimes used above and below instead of "flat electrode element," although this always refers to a flat electrode element. Flat electrode elements include, for example, monocells, anodes, cathodes, separators, anode-separator combinations, cathode-separator combinations, or anode-separator-cathode-separator combinations.

[0015] The device according to the invention can be designed for stacking flat electrode elements of a stream of flat electrode elements comprising a plurality of flat electrode elements. The or at least some consecutive flat electrode elements of the stream originate in particular from one and the same material web or were separated from one and the same material web in a separation process by a separation device.

[0016] For this purpose, the device according to the invention can have a stacking device which is designed to stack the flat electrode elements and which has at least one rotatable stacking wheel with a plurality of stacking wheel compartments, each of which is designed to receive a flat electrode element. In addition, the transport device of the device can be designed to transport the flat electrode elements one after the other along the transport path to the stacking device and / or into the stacking wheel. In this way, an electrode stack with flat electrode elements can be produced, e.g. of an electrochemical energy store or an energy converter. Similar flat electrode elements, but also different flat electrode elements, can be stacked in the electrode stack.

[0017] The spacing enlargement device is designed to increase the spacing between the flat electrode elements, in particular to a processing distance. The processing distance to which the spacing between the flat electrode elements is increased by the spacing enlargement device is in particular at least 5 mm, preferably at least 10 mm, particularly preferably at least 20 mm. For example, the spacing enlargement device is arranged along the transport path of the flat electrode elements upstream of the stacking device. The device can also have several identical or different spacing enlargements, e.g., to achieve larger processing distances.

[0018] The distance-increasing device is designed to accelerate the planar electrode elements in order to increase their distance. For example, the distance-increasing device is designed to increase the distance or accelerate the movement by applying targeted mechanical force to the respective planar electrode element.

[0019] During transport to the spacing enlargement device, the flat electrode elements each have a separation distance from each other, which was created by separating the individual flat electrode elements from the material web. The spacing enlargement device ensures that the flat electrode elements are each spaced a sufficiently large distance or processing distance from each other, which is greater than the separation distance of the flat electrode elements by which the flat electrode elements were spaced from a material web during the separation process.

[0020] The spacing of the flat electrode elements is understood to be the distance between two consecutive electrode elements (in the stream), in particular the distance between the rear edge of a leading flat electrode element and the front edge of a subsequent flat electrode element immediately following the leading flat electrode element. It is assumed that all or at least a large number of the flat electrode elements in the stream have the same or approximately the same length. Therefore, with the spacing, as defined here, the leading edge distance between the two leading edges of the consecutive flat electrode elements is generally also increased, which is important for the correct insertion of the consecutive flat electrode elements into the individual compartments of the forklift wheel.

[0021] Preferably, the spacing enlargement device enlarges the spacing of the successive flat electrode elements such that, after passing through the spacing enlargement device, the processing spacing between the successive flat electrode elements is at least approximately the same for all or at least a plurality of successive flat electrode elements (of the current). This makes it possible to achieve a uniformly high stacking quality of the electrode stack produced from these flat electrode elements by the stacking wheel. Since the leading edge spacing between the leading edges of the successive flat electrode elements is generally also at least approximately the same, a uniform transport of the electrode elements into the rotating stacking wheel is achieved, which further improves the stacking quality.

[0022] The distance enlargement device or a control device of the distance enlargement device can also be designed to generate different processing distances between the electrode elements. For example, the processing distance for lower-quality electrode elements can be selected to be larger than for higher-quality electrode elements. This has the advantage that lower-quality electrode elements can be stacked or sorted out with greater reliability.In order to generate different processing distances depending on the quality, information about the quality of the electrode elements - which applies to several electrode elements or individually for each electrode element - can be transmitted to the control device of the distance enlarging device from externally or from a sensor device of the device (arranged along the transport path in front of the distance enlarging device), which comprises one or more sensors designed to detect measurement signals of the flat electrode elements and derives information about the quality of the electrode elements therefrom.

[0023] In the event that the planar electrode elements actually have different lengths, the distance enlarging device can also be designed to produce different processing distances between the electrode elements (between rear edge and front edge), preferably in such a way that the front edge distances between the successive planar electrode elements are at least approximately the same for all or at least a plurality of successive planar electrode elements (of the current).

[0024] In the event that the leading edges of the planar electrode elements arrive at the spacing device at different times, the spacing device can also be configured to adjust the processing distances between the electrode elements (between the rear edge and the leading edge) such that the leading edge distances between the consecutive planar electrode elements are at least approximately equal for all or at least a plurality of the consecutively transported planar electrode elements. In this way, spacing corrections can be performed.

[0025] The transport device of the device can be designed to transport the flat electrode elements into the (rotating) forklift wheel at such a high transport speed that the kinetic energy of the respective flat electrode element is sufficient for it to slide out of the transport device into a forklift wheel compartment of the forklift wheel. Preferably, the flat electrode elements slide into the respective forklift wheel compartment at least far enough that the center of gravity or at least half the length of the respective flat electrode element is contained in the respective forklift wheel compartment.

[0026] During operation of the device, the rotatable stacker wheel rotates around a stacker wheel axis, preferably at a uniform rotational speed. Distributed around its circumference, the stacker wheel has a plurality of stacker wheel fingers, between each of which a compartment for receiving an electrode element is formed. The stacking device can be configured to strip the electrode elements received in the compartments of the stacker wheel from the respective compartment of the stacker wheel while the stacker wheel rotates around its stacker wheel axis. The stripping action deposits the electrode elements onto a receiving base on which the electrode stack is formed.For this purpose, the stacking device can have a stripper designed to strip the electrode elements accommodated in the compartments of the stacker wheel from the respective compartment when the stacker wheel rotates about its axis, whereby the electrode elements are deposited onto the electrode stack by the stripping. Alternatively, the stripping from the stacker wheel can also take place without a stripper, e.g., by gravity. The device according to the invention may also have a stack holder designed to accommodate the electrode stack.

[0027] The forklift wheel has (e.g., one or more disc-like) forklift wheel bodies rotatable about the forklift wheel axis, the forklift wheel fingers being arranged distributed over the circumference of the forklift wheel bodies, wherein the forklift wheel fingers are each formed at the radially outer end of the forklift wheel body. The compartments of the forklift wheel are each delimited by two forklift wheel fingers. The forklift wheel fingers can be designed such that the compartments are arcuate, e.g., spiral, or have a straight shape, e.g., slot-like. Preferably, the device has two or more identical forklift wheel bodies on the same rotation axis, which are axially offset from one another and, e.g., rotate synchronously with one another.

[0028] Two or more transport devices can also be used per stacker wheel, connected to the stacker wheel of the stacking device at different angular positions. For example, cathodes and anodes can be fed separately to the same stacker wheel, with the electrode elements (e.g., cathodes and anodes) transported by the different transport devices landing alternately in the stacker wheel compartments and being deposited on the same electrode stack.

[0029] In particular, the spacing enlargement device is designed to increase the spacing of the or each two consecutive electrode elements while the or each two consecutive flat electrode elements are transported through or past the spacing enlargement device. The transport of the flat electrode elements can be carried out at least partially by means of the spacing enlargement device.

[0030] The distance enlarging device is preferably designed to increase the distance between the planar electrode elements by mechanically acting on the planar electrode elements, in particular on each of the planar electrode elements transported individually one after the other.

[0031] Preferably, the distance increasing device is designed to accelerate a first planar electrode element, in particular each first planar electrode element, which is transported downstream to a second planar electrode element immediately following it along the transport path, relative to the second planar electrode element in order to increase their distance.

[0032] If the planar electrode elements arrive at the spacing device at a varying distance from one another, the spacing device, in particular its control device and its acceleration device (described below), can be designed to individually control the strength of the acceleration of the respective first planar electrode element, e.g. as a function of the respective distance between the respective first and the respective second planar electrode element and, if appropriate, also as a function of the respective distance between the respective first planar electrode element and the planar electrode element preceding it. For example, the spacing device accelerateswhose acceleration device accelerates the respective first electrode element more strongly if its distance to the following second electrode element is smaller than a lower limit distance and / or weaker if its distance to the following second electrode element is greater than an upper limit distance. This control of the distance enlarging device (e.g. the acceleration device) can be based on a sensor (e.g. light barrier) arranged upstream of the distance enlarging device, which sensor measures the distance between the successive flat electrode elements. Advantageously, the individual acceleration of the flat electrode elements can achieve a more uniform spacing between the flat electrode elements, which results in better stacking quality of the electrode stack produced by the stacker wheel.

[0033] In some embodiments, the device in the region of the spacing enlargement device, e.g. the transport device or the spacing enlargement device itself, has at least one leading and at least one following transport means along the transport path, which can each have at least one conveyor belt and / or at least one transport roller and / or at least one pair of transport rollers or a combination thereof. For example, the leading and / or following transport means have opposing conveyor belts or conveyor belts (e.g. running on rollers), between which the electrode elements are clamped during transport. The following transport means provides a higher transport speed for the flat electrode elements transported by it than the leading transport means.In particular, the leading and following transport means are designed to transport the flat electrode elements with frictional engagement. The leading transport means provides, for example, a first transport speed for the flat electrode elements transported by it, and the following transport means provides a second transport speed for the flat electrode elements transported by it, which is greater than the first. Preferably, the second transport speed of the flat electrode elements is at least a factor of 1.1, particularly preferably at least a factor of 1.5, greater than the first transport speed. Preferably, the second transport speed of the flat electrode elements is at least 0.3 m / s, preferably at least 1 m / s.

[0034] In particular, the leading transport means is designed to transport the planar electrode elements to an acceleration zone in which the respective first planar electrode element is accelerated relative to the respective second planar electrode element. The following transport means is designed to transport the planar electrode elements away from the acceleration zone, further along the transport path of the planar electrode elements, e.g., toward the stacking device or stacker wheel. The acceleration zone is arranged between the leading and following transport means, and may overlap with them if necessary.

[0035] The acceleration of the leading electrode element increases the distance to the following electrode element to the aforementioned processing distance. After acceleration, the electrode elements are transported further at the higher transport speed of the following transport device. For example, they are transported at this higher transport speed through the entire device to the stacking device and, if necessary, into the stacker wheel.

[0036] Preferably, the distance between a last engagement point of the leading transport means, e.g. a first pair of transport rollers, and a first engagement point of the following transport means, e.g. a second pair of transport rollers, along the transport path of the flat electrode elements is equal to or greater than the length of the flat electrode elements along the transport path. This has the advantage that the following transport means only comes into engagement with the respective flat electrode element when or after it is just leaving or has already left the engagement of the leading transport means. This enables gentle acceleration, since the following transport means then does not have to accelerate or transport the flat electrode elements against the frictional force of the preceding transport means.If necessary, additional free-running rollers can be used between the leading and the following transport means, on which the electrode elements are transported when they are neither in engagement with the leading nor in engagement with the following transport means.

[0037] The last engagement point of the leading transport means is the position along the transport path at which the flat electrode elements are last engaged by the leading transport means during their movement along the transport path. The first engagement point of the following transport means is the position along the transport path at which the flat electrode elements are first engaged by the following transport means during their movement along the transport path.

[0038] For example, the distance between a last engagement point of the leading transport means and a first engagement point of the following transport means is more than the length of the flat electrode elements, e.g. at least 1.5 times the length of the flat electrode elements along the transport path. There is then a section of at least half the length of the electrode elements in which they are neither in engagement with the leading nor with the following transport means. This provides an acceleration section that enables slower and therefore more gentle acceleration. The acceleration in the acceleration section can be carried out by an acceleration device that is arranged on the acceleration section or in the acceleration area or at the transition between the leading and following transport means.

[0039] In some embodiments, the subsequent transport means is also used to accelerate the respective first planar electrode element, wherein no additional acceleration device is used.

[0040] In preferred embodiments, the distance-increasing device comprises an acceleration device arranged in the acceleration region or in the region of the transition between the preceding and the following transport means, which acceleration device is designed to accelerate the respective first planar electrode element, when it is located along the transport path between the preceding and the following transport means (and is transported at the transition to the following transport means, if necessary, by means of the preceding transport means), relative to the preceding transport means in order to increase the distance of the respective first planar electrode element relative to the respective second planar electrode element.For example, the acceleration device can temporarily provide an acceleration pulse to each flat electrode element arriving at the transition between the preceding and following transport means, accelerating it from the speed of the preceding transport means to the speed of the following transport means. The acceleration device achieves a more gentle acceleration of the flat electrode elements than acceleration by the following transport means alone (without an additional acceleration device).

[0041] For example, the distance-increasing device, in particular the downstream transport means or the acceleration device of the distance-increasing device, is designed to accelerate the respective first planar electrode element relative to the second planar electrode element by mechanically acting on the respective first planar electrode element in order to increase their distance. Preferably, the distance-increasing device, in particular the downstream transport means or the acceleration device of the distance-increasing device, is designed to begin the mechanical action on the respective first electrode element, which is carried out to increase the distance, at a time at which the respective second planar electrode element is (still) being transported by the preceding transport means.

[0042] The following transport means or the acceleration device, in particular its mechanical action on the respective first planar electrode element, can be controlled in such a way that the strength of the acceleration of the respective first planar electrode element is set individually, e.g. as a function of the respective distance of the respective first planar electrode element from the respective second electrode element and optionally as a function of the respective distance of the respective first planar electrode element from the planar electrode element preceding it, e.g. as described above in connection with the limit distances.

[0043] The acceleration device can be configured to suck or clamp the respective flat electrode element in order to transfer the force for acceleration to the respective electrode element.

[0044] In some embodiments, the acceleration device comprises a pair of (rotatable / rotating) transport rollers arranged along the transport path in the region of the transition between the preceding and following transport means. The pair of transport rollers comprises at least one upper transport roller arranged above the transport path of the flat electrode elements and at least one lower transport roller arranged below the transport path of the flat electrode elements, between which the flat electrode elements are clamped and which act mechanically on a flat electrode element transported between them in order to accelerate it. For this purpose, only one or both of these transport rollers are driven by a drive.

[0045] In order to prevent rotation of the electrode elements during their acceleration, at least one further upper transport roller is arranged concentrically to the upper transport roller (e.g. on the same drive shaft) and laterally offset therefrom and / or at least one further lower transport roller is arranged concentrically to the lower transport roller (e.g. on the same drive shaft) and laterally offset therefrom, which form a laterally offset further transport roller pair, between which the electrode elements are also clamped and accelerate the electrode elements in the same way as the transport roller pair.

[0046] For example, the distance between the acceleration device, in particular the pair of transport rollers, and the leading transport means is selected to be large enough that the electrode element is only gripped by the acceleration device (e.g., by the clamping between the transport rollers of the transport roller pair) at the same time as or after the electrode element is being pulled out of a clamp of the leading transport means / has already been pulled out. If this distance is selected to be greater than the electrode element length, additional free-running rollers can be used between the leading transport means and the acceleration device, in particular the pair of transport rollers. Alternatively, the acceleration device can also grip the respective electrode element before the electrode element has left the leading transport means, e.g., its clamping.

[0047] Typically, when the flat electrode elements are accelerated relative to the leading transport means, if the leading transport means is still engaged / frictionally connected with the flat electrode elements, the frictional force of the leading transport means would counteract the acceleration of the flat electrode element and place mechanical stress on the flat electrode elements. To minimize mechanical stress during acceleration, the leading transport means can be designed to transport the flat electrode elements in such an unfixed manner or with such low static friction that the flat electrode elements can be accelerated relative to the leading transport means while being transported by the leading transport means, e.g., they can be made to roll on or slide relative to the leading transport means without being damaged.For example, the leading transport means is designed to transport the planar electrode elements without holding them in place with respect to their relative movement relative to the leading transport means.

[0048] In order to transport the electrode elements in such an unfixed manner or with such low static friction or without holding them,

[0049] - the preceding means of transport has one or more transport rollers or pairs of transport rollers with an integrated freewheel or

[0050] - the leading transport means transports the electrode elements by means of a static friction force selected to be so low that they can be accelerated relative to the leading transport means or made to slide relative to the leading transport means without being damaged, or

[0051] - the preceding transport means must be designed to transport the flat electrode elements without clamping, i.e. without clamping the flat electrode elements during transport.

[0052] For jam-free transport, the leading transport means can be arranged on one side only, e.g. underneath, of the transport path. This means that along the transport path, in the area of ​​the leading transport means, a transport means is arranged on one side only / below the transport path. This can be, for example, a conveyor belt arranged on one side only / below the transport path or one or more conveyor rollers arranged on one side only / below the transport path, wherein (with regard to the transport path) opposite the leading transport means / above the transport path - at least immediately in front of the acceleration device - there is no pressure element (such as an opposing conveyor belt / transport roller) that presses the electrode element against the one-sided leading transport means, in particular at the time of acceleration by means of the acceleration device.Clamp-free transport by means of the preceding transport means achieves gentle acceleration / acceleration with only low mechanical stress on the flat electrode elements.

[0053] If the leading transport means is designed to transport the flat electrode elements unfixed or with low static friction, it is possible without any problems for the distance between a last engagement point of the leading transport means and a first engagement point of the following transport means or the distance between a last engagement point of the leading transport means and the first engagement point of the acceleration device along the transport path of the flat electrode elements to be selected to be smaller than the length of the flat electrode elements along the transport path.

[0054] In one embodiment of the distance enlarging device, the transport rollers of the transport roller pair each have an uneven radius, which increases along the rotation direction of the respective transport roller, once or more than once, from a first roller radius continuously along a ramp to a larger second roller radius (then possibly remains constant and then abruptly or continuously returns to the first roller radius). The first roller radius corresponds to the first transport speed of the flat electrode elements and the second roller radius to the second transport speed of the flat electrode elements. The transport rollers of the transport roller pair are, for example,rotates at a constant angular velocity, which is selected such that the transport rollers in the region of the first roller radius provide the first transport speed of the flat electrode elements and the transport rollers in the region of the second roller radius provide the second transport speed of the flat electrode elements. In other exemplary embodiments of the distance increasing device, this is designed to modulate the angular velocity of the transport rollers of the transport roller pair in order to accelerate the electrode elements. In particular, the angular velocity of one or more upper and / or one or more lower transport rollers of the distance increasing device is modulated such that the transport speed of the respective electrode element is changed from the first to the second transport speed by the action of the transport rollers.For example, the angular velocity of the transport rollers of the transport roller pair is modulated so that the path speed of the transport rollers is varied periodically, in particular between exactly or approximately the first transport speed and exactly or approximately the second transport speed of the flat electrode elements. The transport rollers of the transport roller pair preferably each have a uniform radius. The path speed of the transport rollers is increased, preferably continuously, from the first transport speed to the second transport speed of the flat electrode elements and then reduced back to the first transport speed in order to be ready for the acceleration of the next electrode element.

[0055] In one of these embodiments of the distance enlarging device, the modulation of the angular velocity is achieved in that the transport roller pair is driven by at least one non-circular gear with a (uniformly running) drive, wherein the modulation of the angular velocity is achieved, for example, by a non-concentric transmission coupling between the drive and the transport roller pair.

[0056] In another of these embodiments of the distance enlarging device, the modulation of the angular velocity is achieved by driving one or both transport rollers of the transport roller pair by means of a modulatable rotary drive, e.g., by means of a motor with variable speed. The time of modulation is preferably controlled as a function of the time of arrival of the electrode element to be accelerated at the transition between the leading and the following transport means, in particular by means of at least one sensor (e.g., a light barrier) that detects the arrival of the electrode element to be accelerated at the transition. The sensor is preferably positioned at the transition in such a way that it registers the leading edge of the respective flat electrode element when it is just leaving or has left the engagement of the leading transport means.The sensor preferably detects the leading edge between the last engagement point of the preceding transport means and the clamping point of the transport roller pair.

[0057] In a further embodiment of the distance-enlarging device, the acceleration device has a suction conveyor belt arranged above the transport path of the flat electrode elements, which is designed to lift an electrode element, which is being transported to the transition at the first transport speed by the preceding transport means, from the preceding transport means by suction, to accelerate it during and / or during the suction, in particular from the first to the second or a transport speed lying between these, and to deposit it on the following transport means after the acceleration, in particular when it has accelerated the electrode element to the second or the transport speed lying between them. If necessary, the suction conveyor belt can overlap with the preceding and / or following transport means along the transport path of the electrode elements.

[0058] To accelerate one or more flat electrode elements individually more strongly than others, the second transport means, the pair of transport rollers, or the suction conveyor belt can temporarily provide an even higher transport speed for the respective flat electrode element(s) than for the other flat electrode elements (which do not require greater acceleration and experience the normally increased transport speed). For an individually weaker acceleration of one or more flat electrode elements, a correspondingly less increased transport speed is provided.

[0059] With the method according to the invention or with the device according to the invention, the flat electrode elements can optionally also be sorted, e.g. before they are stacked. In one embodiment, the device has a sensor device for this purpose, which comprises one or more sensors designed to detect measurement signals from the flat electrode elements. The sensor device is arranged along the transport path of the electrode elements upstream of a sorting device. Detection preferably takes place while the flat electrode elements are transported past the sensor device. The device then also comprises an evaluation device designed to test the flat electrode elements based on the measurement signal detected for the respective flat electrode element by means of at least one test criterion, e.g. with regard to the quality of the electrode element.The test may include a visual test and / or an electrical test of the electrode elements. The evaluation device is designed to generate a test result upon testing the respective flat electrode element, indicating whether or not the respective flat electrode element meets the at least one test criterion.

[0060] The device designed for sorting the electrode elements also has a sorting device arranged downstream of the sensor device along the transport path, which is designed to sort the flat electrode elements depending on the respective test result. The sorting device is designed, in particular, to sort out from the stream those flat electrode elements for which the respective test result indicates that they do not meet the at least one test criterion, and to leave the other flat electrode elements (those flat electrode elements that meet the at least one test criterion) in the stream of flat electrode elements (which is transported, for example, to the stacking device).

[0061] The transport device is designed to transport the planar electrode elements one after the other along the transport path to the sensor device, then to the sorting device, and optionally thereafter to a stacking device. For example, the sorting device has at least one diverter designed to selectively separate individual planar electrode elements from the stream. Preferably, the transport path of the planar electrode elements between the sensor device and the sorting device has an evaluation section, wherein the evaluation device is designed to perform the testing of the planar electrode elements at least partially during their transport along the evaluation section.

[0062] Preferably, the distance enlarging device is arranged upstream of the sorting device, viewed along the transport path of the planar electrode elements. In particular, the distance enlarging device can be arranged directly upstream of the sorting device along the transport path of the planar electrode elements. Alternatively, a transport section for the planar electrode elements and / or the sensor device and / or another device can be present between the distance enlarging device and the sorting device along the transport path of the planar electrode elements. If the distance enlarging device is arranged upstream of the sorting device, this has the advantage that even at increased transport speeds, a reliable sorting out or branching off of an individual electrode element into another transport branch is possible, since the sorting device, e.g.whose switch can more reliably exercise mechanical access to only a specific one of the successive electrode elements, without impairing the passing (non-sorting) of the respective subsequent or previous electrode element.

[0063] Preferably, the spacing enlargement device is arranged along the transport path of the planar electrode elements upstream of the sensor device (directly upstream of the sensor device or with a section in between). As a result, the spacing between the electrode elements is increased even before the measurement signals are detected. The increased spacing achieves more reliable separation of the measurement signals from successive planar electrode elements. Alternatively, the spacing enlargement device can be arranged along the transport path of the planar electrode elements or downstream of the sensor device, in which case it is preferably arranged between the sensor device and the sorting device. In principle, however, the spacing enlargement device can also be arranged downstream of the sorting device, e.g., between the sorting device and the stacking device.

[0064] The device preferably has a control device which is designed to control the transport device for transporting the flat electrode elements and the sorting device for sorting out individual flat electrode elements, e.g. switching the switch in order to sort out individual flat electrode elements if necessary. The control device can, if necessary, also control the distance increasing device or acceleration device for increasing the distance between the flat electrode elements, e.g. their timing, e.g. as a function of the time of arrival of the respective flat electrode element or its front edge at the distance increasing device or as a function of the time of arrival at the transition between the preceding and the following transport means. Alternatively, the distance increasing device oracceleration device but also run continuously without the need for individual control for the individual flat electrode elements. The invention also relates to a method for transporting and, if appropriate, for stacking flat electrode elements, in particular with the aid of the device described above, from a stream of flat electrode elements which has a multiplicity of flat electrode elements. The flat electrode elements of the stream were separated from one or the same material web by a separating device in a separating process, e.g. in a device upstream of the device, at least some successive flat electrode elements were separated from one and the same material web. In the stream, the electrode elements have a separation distance from one another which the flat electrode elements obtained during the separation process carried out on the material web by the separating device.

[0065] In particular, the current of the flat electrode elements is generated using the following steps:

[0066] - Providing a material web along the longitudinal direction of which several flat electrode elements are arranged (e.g. directly following one another) and

[0067] - Transporting the material web to a separating device and separating the individual flat electrode elements from the material web by the separating device during a separating process, wherein the flat electrode elements are spaced apart from one another by a separation distance determined by the separation process. The separation distance corresponds in particular to the width of a separation line along which the flat electrode elements are separated from the material web during the separation process. This separation distance is generally less than 5 mm and can even be less than 0.1 mm.

[0068] In the method, the planar electrode elements of the current are transported one after the other along a transport path with the aid of at least one transport device to a distance enlarging device which increases the distance between the planar electrode elements by accelerating the planar electrode elements, in particular from the separation distance to a processing distance.

[0069] After the spacing has been increased, the flat electrode elements can be transported to different destinations, e.g., into different transport branches, into which the transport path of the flat electrode elements branches after the spacing increase device. For example, this makes it easier to sort out one or more of the flat electrode elements from the flow of flat electrode elements.

[0070] Alternatively or additionally, after the spacing has been increased, the electrode elements can be transported to a stacking device which is designed to stack the flat electrode elements. The stacking device has, for example, at least one rotatable stacking wheel with a plurality of stacking wheel compartments, each of which is designed to receive a flat electrode element. The flat electrode elements are transported, in particular by means of the transport device, to a spacing enlargement device which increases the spacing of the flat electrode elements by accelerating the flat electrode elements, in particular from the separation distance to a processing distance. This is carried out, for example, by the stacking device before stacking. In this case, the spacing enlargement device is arranged in front of the stacking device or in front of the stacking wheel, as viewed along the transport path.The processing distance that the flat electrode elements receive from the spacing enlargement device is greater than the separation distance of the flat electrode elements that the flat electrode elements received during the separation process performed on the material web by the separation device. The stacking device has, for example, at least one rotatable stacking wheel with several stacking wheel compartments, each designed to accommodate a flat electrode element. Stacking by means of the stacking wheel comprises, for example, the following steps:

[0071] - Transporting one electrode element at a time into a compartment of the forklift wheel rotating around the forklift wheel axis, in particular with the above-mentioned higher / second transport speed, and

[0072] - Stripping the electrode elements accommodated in the compartments of the stacker wheel from the respective compartment of the stacker wheel, if necessary by means of a stripper, while the stacker wheel rotates about its stacker wheel axis, whereby the electrode elements are deposited by the stripping onto an electrode stack which is arranged, for example, on a receiving base of the stacking device.

[0073] In a preferred method, the electrode elements can be transported along the transport path one after the other to a sensor device, to a sorting device and then, if present, to the above-mentioned stacking device, wherein the following steps are carried out:

[0074] - Transporting the flat electrode elements of the current to the sensor device and detecting measurement signals of the flat electrode elements by the sensor device, e.g. while the flat electrode elements are transported past the sensor device,

[0075] - Testing the flat electrode elements based on the measurement signal recorded for the respective flat electrode element by means of at least one test criterion, in particular with regard to their quality, wherein, during testing of the respective flat electrode element, a test result is generated which indicates whether the respective flat electrode element satisfies the at least one test criterion or not; preferably, the flat electrode elements are transported further towards the sorting device during testing,

[0076] - transporting the flat electrode elements to the sorting device and sorting the flat electrode elements by the sorting device depending on the respective test result, wherein the sorting device sorts out from the stream those flat electrode elements for which the test results indicate that they do not meet the at least one test criterion, and leaves the other flat electrode elements (those flat electrode elements that meet the at least one test criterion) in the stream of flat electrode elements,

[0077] - and optionally transporting the planar electrode elements, in particular the planar electrode elements left in the stream after sorting, to the stacking device arranged after the sorting device, which is designed to stack the planar electrode elements in order to produce an electrode stack with the planar electrode elements (and optionally further elements).

[0078] In the method, the flat electrode elements are transported by the stacking device to the spacing enlargement device before stacking, which increases the spacing between the flat electrode elements, in particular from the separation distance to the processing distance. In a particularly preferred method, the flat electrode elements are transported to the spacing enlargement device before sorting by the sorting device and, particularly preferably, also before testing by the testing device.

[0079] The advantages presented with reference to the device according to the invention apply accordingly to the method according to the invention. Further features of the invention emerge from the claims, the figures, and the description of the figures. Exemplary embodiments of the invention are explained in more detail below with reference to a schematic drawing. In the drawings:

[0080] Fig. la A first embodiment of a device for transporting and stacking flat electrode elements with a distance enlarging device, Fig. lb schematically the separation of the individual electrode elements from a material web,

[0081] Fig. 2a, b a first and second embodiment of a distance enlarging device,

[0082] Fig. 3 shows a second embodiment of a device for transporting and, if necessary, stacking flat electrode elements with a distance enlarging device, a sensor device and a sorting device,

[0083] Fig. 4 overall principle of a third, fourth and sixth embodiment of the distance enlarging device,

[0084] Fig. 5a, b, c a third embodiment of a distance enlarging device,

[0085] Fig. 6a, b a fourth embodiment of a distance enlarging device,

[0086] Fig. 7 shows a fifth embodiment of a distance enlarging device,

[0087] Fig. 8 shows a sixth embodiment of a distance enlarging device.

[0088] Figure 1 shows a first embodiment of a device 5 for transporting and stacking flat electrode elements. A manufacturing device 100 for flat electrode elements 1 is arranged upstream of the device 5, generating a stream of flat electrode elements 1 that are transported from the manufacturing device 100 to the device 5 for stacking the electrode elements. The flat electrode elements can be fuel cells or battery cells, or components thereof used in their production.

[0089] The manufacturing device 100 uses a continuous material web

[0090] 101, along the longitudinal direction of which several flat electrode elements 1 are arranged contiguously and directly adjacent to one another. The material web can comprise one or more layers, e.g., at least one separator layer, to which one or more cathode layers and / or anode layers are applied, e.g., alternately. For example, several cathodes and anodes are separated from one another by separator layers. The material web can, for example, have the layer sequence anode-separator-cathode-separator.

[0091] In the production device 100, the material web 101 is transported to a separating device 102, which separates the individual flat electrode elements 1 from the material web 101, e.g., by cutting, punching, or lasering. During this separating process, the flat electrode elements 1 are each spaced apart from one another by a separation distance a, which is solely determined by the separation process. The separation distance a corresponds to the width of a separation line (cf. Fig. 1b) along which the flat electrode elements are separated from the material web during the separation process. The separation distance a can, for example, be determined by the width of the separation tool used during the separation process and is usually less than 5 mm. In the case of laser cutting or shearing, it is, for example, <0.1 mm.

[0092] The stream of flat electrode elements provided by the manufacturing device 100 therefore comprises a plurality of flat electrode elements 1 that have been separated from the same material web 101. For example, the flat electrode elements are individual anodes, individual cathodes, anode-separator combinations or cathode-separator combinations, e.g., half-cells, or anode-separator-cathode-separator combinations, e.g., monocells.

[0093] In the device 5, the stream of flat electrode elements 1 is transported by means of a transport device along a transport path 10 to a stacking device 17. The transport device has, for example, several transport rollers 3 and / or opposing conveyor belts that circulate around rollers and between which the flat electrode elements are clamped and transported.

[0094] The stacking device 17 has a stacker wheel 7 which can be rotated about a stacker wheel axis and has a plurality of stacker wheel compartments which are each designed to receive a flat electrode element. The stacker wheel 7 has a plurality of stacker wheel fingers distributed over the circumference of the stacker wheel, between which a compartment for receiving an electrode element 1 is formed. It is rotated about its axis by means of a motor such that an electrode element 1 is inserted into a compartment of the respective stacker wheel 7 by means of the transport device. The electrode element 1 received in the respective compartment can be stripped out of the stacker wheel 7 by means of a stripper 4 in order to place it on a stack 2. The stacker wheel fingers and compartments run spirally around the axis of rotation, but can alternatively also be straight, e.g. radial, and if necessary.have a larger compartment width than shown so that the electrode elements 1 are not bent by the shape of the compartment.

[0095] A distance enlarging device 12 is arranged along the transport path 10 in front of the stacking device 17. This device is designed to increase the distance of the or all flat electrode elements from the separation distance a, which was created by separating them from the material web, to a processing distance A that is greater than the separation distance a. Preferably, the processing distance A is at least 20 mm. The distance enlarging device 12 is arranged, for example, in a module 13 of the device.

[0096] Before stacking, further processing steps can be performed on the electrode elements 1 in the device 5, e.g., a quality check and, if necessary, sorting out electrode elements from the stream. Examples of further processing steps are described in the embodiment shown in Fig. 3.

[0097] The spacing of two consecutive electrode elements 1 is increased while the respective two planar electrode elements are transported through or past the spacing increase device 12. To increase the spacing of the respective two consecutive electrode elements, the leading electrode element 1 is accelerated relative to the electrode element 1' following it in the spacing increase device 12. For this purpose, the spacing increase device 12 preferably has at least one leading and at least one following transport means along the transport path 10, wherein the following transport means provides a higher transport speed for the planar electrode elements transported by it than the leading transport means.

[0098] Figure 2a shows a first embodiment of the spacing device 12. In the device 5 of Fig. 2a, the stream of flat electrode elements 1, for example, arrives in an input area 11, from which it is transported to the spacing device 12 and then to the stacking device 17. In the spacing device 12, a conveyor belt 21 is used as the leading transport means, and a pair of conveyor belts 23, 24 is used as the trailing transport means. The conveyor belts 21 and 23, 24 run at a constant speed, with the trailing pair of conveyor belts 23, 24 running faster than the leading conveyor belt 21.At the transition between the slower conveyor belt 21 and the faster conveyor belt pair 23, 24, the flat electrode elements 1 are gripped by friction as soon as they come into mechanical engagement with the faster conveyor belt pair 23, 24, and accelerated abruptly and transported further in the direction of the stacking device 17 at the greater transport speed of the conveyor belt pair 23, 24. Due to the acceleration of the first, leading electrode element 1, the distance to the second, following electrode element 1' increases to a processing distance A, see Fig. 2a. The conveyor belt 21 transports the flat electrode elements without clamping, i.e. without an opposing pressure element, so that the electrode elements do not have to be accelerated by means of the conveyor belt pair 23, 24 against a strong frictional force (associated with clamping).

[0099] Fig. 2b shows a modification of the first embodiment, in which the conveyor belt 21 is spaced from the conveyor belt pair 23, 24 by more than the electrode element length, so that the respective flat electrode element is no longer braked by the frictional force of the conveyor belt 21 at the time of acceleration. A conveyor roller 3 is arranged between them, which is freely mounted to facilitate acceleration by the conveyor belt pair 23, 24. Instead of the conveyor belts 21, 23, 24, conveyor rollers can also be used in the embodiment of Figs. 2a, 2b.

[0100] Figure 3 shows a second embodiment of a device 5 for transporting electrode elements. The device 5 has, along the transport path after an entrance area 11 and after a distance enlarging device 12, a sensor device 14 with one or more sensors that record measurement signals from the flat electrode elements, e.g., for their quality inspection. For example, an image and, if applicable, electrical signals from the electrode elements are recorded and evaluated. An evaluation device 15 tests the flat electrode elements based on the recorded measurement signals using at least one test criterion and generates a test result for the respective flat electrode element, which indicates whether or not the respective flat electrode element fulfills the at least one test criterion.After the sensor device 14, the flat electrode elements 1 are transported further to a sorting device 16, which is arranged along the transport path after the sensor device and is designed to sort the flat electrode elements depending on the respective test result. The sorting device has a switch 61, which is designed to selectively sort out individual flat electrode elements from the stream. Between the sensor device 14 and the sorting device 16 is an evaluation section 19. The evaluation device 15 tests the flat electrode elements as they are transported along the evaluation section 19. The flat electrode elements are transported along the transport path by means of the transport devices 3, 23, 24 one after the other to the sensor device 14, the sorting device 16 and then via a switch 71 optionally to the stacking device 17 or past it, e.g.to another device 9 of the device.

[0101] The device 5 also has a control device 18, which receives the respective test result from the evaluation device 15 and controls the sorting device 16 for sorting out individual flat electrode elements depending on the respective test result. The control device 18 also controls the transport devices 3, 23, 24 and, if necessary, the spacing enlargement device 12.

[0102] Alternatively, the device 5 of the second embodiment can also be implemented without a stacking device 17, so that the electrode elements not sorted out in the sorting device 16 are transported to the further device 9 of the device. The devices 5 of the other embodiments can also be implemented without a stacking device 17, and the electrode elements can instead be transported to another device.

[0103] Figure 4 shows the overall principle of a third, fourth, and sixth exemplary embodiment of the distance-increasing device 12. In a transition region between the leading conveyor 21 and the following conveyor 23, 24, an acceleration device is additionally arranged, which in this case comprises a rotatable, driven transport roller pair with two opposing transport rollers 25, 26. These act mechanically on a flat electrode element 1 transported between them in order to accelerate it and thereby increase the distance to the second electrode element 1' following it. Instead of conveyor belts 21, 23, 24, transport rollers can also be used in these exemplary embodiments.To prevent the electrode elements from rotating during acceleration, at least one further transport roller 25 is arranged on the shaft of the transport roller 25, and at least one further transport roller 26 is arranged on the shaft of the transport roller 26. These transport rollers can be identical to the transport rollers 25 and 26, respectively, and are used to accelerate the electrode elements. The third, fourth, and sixth embodiments, which all use a pair of transport rollers, can also be combined with one another. For example, the angular velocity of the transport rollers 25, 26 of the third and fourth embodiments can be modulated according to the sixth embodiment to assist acceleration.

[0104] Figures 5a, b, c show a third embodiment of the distance enlargement device 12, which follows the principle shown in Fig. 4. Figures 5a and 5b show the distance enlargement device at two different times t1 and t2. Figure 5c shows the temporal progression of the angular or path speed of the accelerating transport roller pair 25, 26. In Fig. 5a, b, the transport rollers 25, 26 of the transport roller pair each have a uniform radius. The angular velocity and thus also the path speed of at least one of the transport rollers 25, 26 of the transport roller pair is modulated by driving the transport rollers with the aid of two non-circular gears 27, 28, which may, for example, have an oval or elliptical shape.The first gear 27 is fixedly mounted on the shaft of the transport roller 26 and meshes with a second gear 28 mounted on a drive shaft driven at a constant speed. The gear 28 is driven by the drive shaft at a constant angular velocity, but due to its shape, has an oscillating path velocity, which it transmits to the gear 27 and thus also to the transport roller 26. The direction of rotation of the gears and the transport roller 26 is indicated by arrows in Figs. 5a and 5b. The transport roller 25, located opposite the speed-modulated transport roller 26, is a freewheel roller.

[0105] Due to this non-concentric transmission coupling, a low path speed vl is generated on the transport roller 26 at the first time t1 shown in Fig. 5a and a greater path speed v2 at the second time t2 shown in Fig. 5b. At a constant input speed of the motor that drives the gear 28, an oscillating output is generated via the non-concentric, e.g. elliptical, coupling of the two gears 27, 28. As a result, the path speed of the transport roller 26 is modulated between the first path speed vl and the second path speed v2, see Fig. 5c. The angular position of the gears 27, 28 is selected such that at the coupling point of the two gears a small radius of the gear 28 meets a large radius of the gear 27. As a result, the modulation of the path speed has an even greater effect on the angular velocity of the gear 27 and the transport roller 26.For fine adjustment of the speed change, the angular position of the gear 28 can be varied relative to the gear 27. To prevent rotation of the electrode elements during their acceleration, at least one further such transport roller 26 is arranged on the shaft of the transport roller 26 and used to accelerate the electrode elements 1.

[0106] A flat electrode element 1, which at time t1 is clamped between the two transport rollers 25, 26, is thus accelerated from the first to the second path speed. The first path speed v1 of the transport roller 26 corresponds, for example, to the transport speed of the transport rollers 3a, which transport the electrode element 1 to the transport rollers 25, 26, and the second path speed v2 of the transport roller 26 corresponds, for example, to the transport speed of the transport rollers 3b, which transport the electrode elements 1 further past the transport rollers 25, 26. Although the transport rollers 3a are driven, they are equipped with a freewheel that allows the electrode element to be pulled out of its clamp without resistance.

[0107] Figures 6a, b show a fourth embodiment of the distance enlarging device 12, which follows the principle shown in Figure 4. Figures 6a and 6b show the distance enlarging device at two different times t1 (Figure 6a) and t2 (Figure 6b), wherein in Figure 6b the conveyor belts 21, 23 and conveyor rollers 3a, 3b have been omitted for the sake of simplicity.

[0108] The electrode elements 1 are transported at a distance a on a one-sided conveyor belt 21, see Fig. 6a. Two driven conveyor rollers 3a are arranged above and below the conveyor path, the path speed of which corresponds to the peripheral speed of the conveyor belt 21. Although the conveyor rollers 3a are driven, they are equipped with a freewheel that allows the electrode element to be pulled out of its clamp without resistance. Along the conveyor path (arrow) there is a pair of shafts on which two conveyor rollers 25, 26 of a conveyor roller pair are seated. Each of these rollers has an irregular radius and is driven at a constant angular velocity via a drive 29, e.g., a belt or gear. This is followed by the conveyor belt 23, which transports the electrode elements 1 further at the higher speed.If necessary, a further transport roller 3b is arranged opposite the conveyor belt 23. The radius of the transport rollers 25, 26 increases continuously along their direction of rotation from a first roller radius to a larger second roller radius, so that they have a ramp R along their circumference. At the smaller first roller radius, the transport rollers 25, 26 have the path speed of the conveyor belt 21, while at the larger second roller radius they have the higher path speed of the conveyor belt 23. If an electrode element 1 is now clamped between the transport rollers 25, 26, it is accelerated due to the roller radius of the transport rollers increasing along the ramp R, see Fig. 6b. This results in a greater distance A between the accelerated and the following electrode element.The two shafts of the transport rollers 25, 26 are spring-loaded perpendicular to the transport plane of the electrode elements so that they can avoid the roller radius increasing at the clamping point.

[0109] The ramp R can be designed such that it has a segment corresponding to the increase in the roller radius in which the transport rollers 25, 26 constantly have the larger second roller radius. Alternatively, or in addition to the segment with a constant larger second roller radius, the transport rollers 25, 26 can be equipped with an integrated freewheel, which enables the electrode element 1 to be removed without resistance by the conveyor belt 23.

[0110] The angular position of the transport rollers 25, 26 is selected such that at the time the electrode element 1 arrives at the clamping point, the smaller diameter of the transport rollers 25, 26 is at the clamping point of the electrode element 1. The withdrawal of the respective electrode element 1 by the faster conveyor belt 23 takes place, for example, at a time when the larger diameter of the transport rollers 25, 26 is at the clamping point. The respective electrode element 1 leaves the engagement of the transport roller pair 25, 26 in the direction of the conveyor belt 23 before it engages again with the smaller first roller radius. This can be achieved by selecting a specific phase position for the arrival of the electrode element during the rotation of the transport roller pair 25, 26, in which phase position the end of the ramp R only comes into engagement with the rear area of ​​the respective electrode element.

[0111] In the acceleration area of ​​the electrode elements, a sliding plate G is optionally arranged directly below the transport path 10. This sliding plate serves to guide the electrode elements while they are accelerated by the pair of transport rollers 25, 26. To prevent rotation of the electrode elements during their acceleration, at least one further such transport roller 25 is preferably arranged on the shaft of the transport roller 25 and in phase with it, and at least one further such transport roller 26 is arranged on the shaft of the transport roller 26 and in phase with it, and used to accelerate the respective electrode element.

[0112] Figure 7 shows a fifth embodiment of the distance enlargement device 12. In this case, unlike in Fig. 4, a suction conveyor belt S is used as the acceleration device between the slower leading and the faster following transport means, which is arranged in the region of the transition between a leading conveyor belt 21 and a following conveyor belt 23. An electrode element 1, which is transported by means of the conveyor belt 21 at a first transport speed, is lifted off the conveyor belt 21 by suction by means of the suction conveyor belt S. The suction conveyor belt S overlaps with the first and second conveyor belts 21, 23 along the transport path and runs at a constant speed that is greater than the first transport speed.The suction conveyor belt has a multitude of small holes along its entire length, through which a suction device (not shown) acts in a limited suction area B, i.e., it sucks upwards any electrode element located there. The suction can be continuous or activated only synchronized with the arrival of the respective electrode element.

[0113] As a result of the suction, the electrode element 1 comes into frictional engagement with the suction conveyor belt S and is transported with it. As a result of the suction by the suction conveyor belt S, the respective electrode element 1 is accelerated from the first transport speed to the transport speed of the suction conveyor belt S, thus increasing the distance to the following second electrode element 1'. As soon as the respective accelerated electrode element 1 leaves the suction area B of the suction conveyor belt, it is taken over by the following conveyor belt 23, with which it is transported further. The transport speed of the suction conveyor belt S can be equal to the transport speed of the following conveyor belt 23 or between the first transport speed of the preceding conveyor belt 21 and that of the following conveyor belt 23, or even greater than the transport speed of the following conveyor belt 23.Optionally, a further conveyor belt 22 is arranged opposite the first conveyor belt and offset therefrom, and a further conveyor belt 24 is arranged opposite the first conveyor belt and offset therefrom.

[0114] Figures 8a, b, c show a sixth embodiment of the distance enlargement device 12, which again follows the principle shown in Fig. 4. Figure 8a shows the distance enlargement device in a side view and Figure 8b in a plan view of the transport plane of the electrode elements 1. The arrow indicates the transport direction of the electrode elements 1 along the transport path 10. Figure 8c shows the time course of the light barrier signal LS and the time course of the angular or path speed v of the accelerating transport roller pair 25, 26. Arranged one after the other along the transport path 10 of the electrode elements are a first transport roller pair 3a, an accelerating transport roller pair 25, 26 and a second transport roller pair 3b, which have different transport speeds, cf. Fig. 8a.The first transport roller pair 3a is driven by a motor M1 at a low angular velocity corresponding to a low transport speed v1 of the electrode elements, see Fig. 8b. The third transport roller pair is driven by a motor M2 at a higher angular velocity corresponding to a higher transport speed v2 of the electrode elements. Alternatively, the first transport roller pair 3a and / or the third transport roller pair 3b can also be driven by another transport means preceding the first transport roller pair 3a or by another transport means following the third transport roller pair 3b, so that no separate motor M1 or M2 is required.

[0115] One or both transport rollers of the middle transport roller pair 25, 26 are driven by a stepper motor MS, which initially drives them at an angular velocity corresponding to the lower transport speed vl of the first transport roller pair 3a until an electrode element 1 arrives. The modulation of the angular velocity of the transport rollers 25, 26 is generated by varying the motor speed of the stepper motor MS coupled to them. In the area of ​​the accelerating transport roller pair 25, 26 there is a light barrier L, see Fig. 8a, which registers the arrival of the leading edge of the respective electrode element 1 and reports it to a control device (not shown) of the distance enlargement device 12. If an electrode element 1 is registered by the light barrier L, it is already clamped by the accelerating transport roller pair 25, 26.Triggered by the signal LS reported by the light barrier L at time t1, see Fig. 8c, the control device controls the drive of the transport roller pair 25, 26 such that the angular velocity of the transport rollers 25, 26 is increased in order to increase the path speed of the transport rollers 25, 26, starting from the lower first transport speed vl at time t1, up to the higher second transport speed v2 at time t2, see Fig. 8c. As a result, the respective electrode element is accelerated smoothly and continuously from the first transport speed vl of the first transport roller pair 3a to the second transport speed v2 of the second transport roller pair 3b. As a result of the acceleration, the distance between the electrode element 1 that has just been accelerated and the next electrode element l. z, which follows it along the transport path, is increased from a distance a to a larger distance A. The second transport roller pair transports the respective electrode element further at the larger second transport speed v2.

[0116] If the light barrier L subsequently reports to the control device at time t3 that it is no longer registering the electrode element 1, the control device causes the drive of the transport roller pair 25, 26 to reduce the angular velocity of the transport rollers 25, 26 again in response, in such a way that the path speed of the transport roller pair 25, 26 is reduced from the second transport speed v2 back to the first transport speed vl, see Fig. 8c. This takes place until a time t4, which lies within the time gap that exists until the arrival of the next electrode element 1', so that the next electrode element 1' is again gripped at the first transport speed vl. With this principle of increasing the distance, the electrode elements are gently accelerated to a higher transport speed.The accelerating transport rollers 25, 26 have a low mass so that they can quickly implement the dynamics of the acceleration. The first transport roller pair 3a is driven, but has an integrated freewheel so that the clamping force exerted on the electrode element does not counteract the acceleration by the transport roller pair 25, 26. To prevent rotation of the electrode elements during their acceleration, another such transport roller 26 is arranged on the shaft of the transport roller 26 and is driven in phase with it. Analogously, another such transport roller 25 is arranged on the shaft of the transport roller 25 and driven in phase with it and used to accelerate the electrode elements, see Fig. 8b. Instead of a ramp-like curve of the angular or path speed of the transport rollers 25, 26, this can also be modulated using a sinusoidal or similar curve.

[0117] Alternatively, the light barrier L can also be arranged in front of the transport roller pair 25, 26 or their clamping point along the transport direction. This enables earlier acceleration already at the time when the front edge of the electrode element 1 reaches the clamping point. The start of the acceleration by means of the transport roller pair 25, 26 is then slightly delayed compared to the earlier light barrier signal (at t1) so that the acceleration only begins when or after the front edge arrives at the clamping point. The start of the reduction in transport speed is also correspondingly delayed compared to the light barrier signal (at t3). In comparison to the third and fourth embodiments, the principle of the sixth embodiment can be used to easily achieve different distance increases between electrode elements of different lengths. For this purpose, the strength orDuration of acceleration adapted to the length of the electrode element, e.g. so that the leading edge distances of the electrode elements of different lengths are the same.

Claims

Patent claims Device (5) for transporting flat electrode elements (1) of a stream of flat electrode elements which has a multiplicity of flat electrode elements, with a transport device (3, 21, 23, 24) which is designed to transport the flat electrode elements one after the other along a transport path (10), characterized in that the device (5) has a distance enlarging device (12) which is arranged along the transport path of the flat electrode elements and which is designed to accelerate the flat electrode elements (1) in order to increase their distance.Device according to claim 1, characterized in that the device is designed for stacking the planar electrode elements (1) of the stream of planar electrode elements, wherein the device has a stacking device (17) designed to stack the planar electrode elements, wherein the transport device (3, 21, 23, 24) is designed to transport the planar electrode elements one after the other along the transport path (10) to the stacking device (17), and wherein the spacing enlargement device (12) is arranged upstream of the stacking device (17) along the transport path of the planar electrode elements. Device according to claim 2, characterized in that the stacking device (17) has at least one rotatable stacking wheel (7) with a plurality of stacking wheel compartments, each of which is designed to receive a planar electrode element (1). Device according to one of the preceding claims, characterized in that the distance enlarging device (12) is designed to each first planar electrode element (1), in particular each first planar electrode element, which is arranged downstream of a second planar electrode element (1) immediately following it. z ) is transported along the transport path, relative to the second planar electrode element (l z) in order to increase their distance. Device according to one of the preceding claims, characterized in that the device (5) in the region of the distance enlarging device (12), in particular the distance enlarging device itself, has at least one leading transport means (21, 3a) along the transport path, which provides a first transport speed (vl) for the flat electrode elements transported by it, and at least one following transport means (23, 24, 3b) which provides a second transport speed (v2) for the flat electrode elements transported by it, which is greater than the first transport speed (vl).Device according to claim 5, characterized in that the distance enlarging device (12) has an acceleration device (25, 26, S) arranged in the region of the transition between the preceding and the following transport means, which is designed to accelerate the respective first planar electrode element (1) when it is located along the transport path between the preceding and the following transport means, relative to the respective second. flat electrode element (l z) in order to increase their distance. Device according to claim 6, characterized in that the acceleration device has a pair of transport rollers (25, 26) which are arranged along the transport path in the region of the transition between the preceding and the following transport means, and which has at least one upper transport roller (26) arranged above the transport path of the flat electrode elements and at least one lower transport roller (25) arranged below the transport path of the flat electrode elements, between which the flat electrode elements are clamped and which are designed to act mechanically on a flat electrode element transported between them in order to accelerate it.Device according to claim 7, characterized in that the transport rollers of the transport roller pair (25, 26) each have a non-uniform radius, which increases continuously along the rotation direction of the respective transport roller from a first roller radius along a ramp (R) to a larger second roller radius, wherein the first roller radius corresponds in particular to the first transport speed (v1) of the planar electrode elements and the second roller radius corresponds in particular to the second transport speed (v2) of the planar electrode elements. Device according to claim 7, characterized in that the distance-increasing device is designed to modulate the angular velocity of the transport rollers of the transport roller pair (25, 26) in order to accelerate the planar electrode elements. Device according to claim 9, characterized in that the distance-increasing device has at least one non-circular gear (27, 28) and is designed to drive the transport roller pair (25, 26) with a drive via the at least one non-circular gear (27, 28) in order to achieve the modulation of the angular velocity. Device according to claim 9, characterized in that the distance-increasing device is designed to drive the transport rollers of the transport roller pair (25, 26) by means of a modulatable rotary drive in order to achieve the modulation of the angular velocity.Device according to claim 6, characterized in that the acceleration device has a suction conveyor belt (S) arranged above the transport path of the flat electrode elements, which is designed to lift a flat electrode element (1) that is transported to the transition at the first transport speed by the preceding transport means, from the preceding transport means (21) by suction, to accelerate it during and / or during the suction, and to deposit it on the following transport means (23) after the acceleration. Device according to one of the preceding claims, with. - a sensor device (14) designed to detect measurement signals from the flat electrode elements, and - an evaluation device (15) which is designed to test the planar electrode elements on the basis of the measurement signal detected for the respective planar electrode element by means of at least one test criterion, wherein the evaluation device is designed to, when testing the to generate a test result for each flat electrode element indicating whether the respective flat electrode element (1) satisfies the at least one test criterion or not, and - a sorting device (16) arranged downstream of the sensor device (14) along the transport path (10) of the planar electrode elements and designed to sort the planar electrode elements depending on the respective test result, wherein the transport device (10) is designed to transport the planar electrode elements (1) along the transport path (10) one after the other to the sensor device (14) and to the sorting device (16), and, if present, to the stacking device (17). Device according to claim 13, characterized in that the spacing enlargement device (12) is arranged upstream of the sorting device (16) along the transport path (10) of the planar electrode elements, wherein the spacing enlargement device is preferably arranged upstream of the sensor device (14) along the transport path (10).Method for transporting flat electrode elements (1), in particular with the aid of the device (5) according to one of the preceding claims, a stream of flat electrode elements which has a multiplicity of flat electrode elements which have been separated from a material web, in particular in a separating process by a separating device, wherein the flat electrode elements (1) of the stream are transported individually one after the other along a transport path (10) with the aid of at least one transport device, characterized in that the flat electrode elements (1) are transported to a distance enlarging device (12) which accelerates the flat electrode elements (1) in order to increase their distance, in particular to a processing distance. A method according to claim 15 for stacking flat electrode elements, characterized in that the flat electrode elements (1) are transported individually one after the other along the transport path (10) with the aid of the transport device to a stacking device (17) designed to stack the flat electrode elements. The flat electrode elements (1) are transported to the spacing enlargement device (12) prior to stacking by the stacking device (17). The stacking device comprises, for example, at least one rotatable stacking wheel (7) with a plurality of stacking wheel compartments, each of which is designed to accommodate a flat electrode element. A method according to claim 15 or 16, characterized in that the current of the flat electrode elements is generated by means of the following steps: - providing a material web (101) along the longitudinal direction of which a plurality of flat electrode elements are arranged, and - Transporting the material web to a separating device (102) and separating the individual planar electrode elements from the material web by the separating device during a separating process, wherein the planar electrode elements are each spaced apart from one another by a separation distance (a) during the separating process, which corresponds to the width of a separation line along which the planar electrode elements are separated from the material web during the separation process. Method according to one of claims 15 to 17, wherein the electrode elements are transported along the transport path (10) individually one after the other to a sensor device (14) and to a sorting device (16) and, if present, then to the stacking device (17), comprising the steps: - transporting the flat electrode elements of the current to the sensor device and detecting measurement signals of the flat electrode elements by the sensor device (14), - Testing the flat electrode elements based on the measurement signal recorded for the respective flat electrode element by means of at least one test criterion, wherein during testing of the respective flat electrode element a test result is generated which indicates whether the respective flat electrode element fulfils the at least one test criterion or not, - transporting the flat electrode elements to the sorting device (16) and sorting the flat electrode elements by the sorting device depending on the respective test result, - if necessary, transporting the flat electrode elements, in particular the flat electrode elements left in the stream after sorting, to the stacking device (17) arranged after the sorting device (16), which is designed to stack the flat electrode elements, characterized in that the flat electrode elements, before sorting by the sorting device (16) and if necessary before stacking by the stacking device (17), are transported to the distance enlarging device (12), which accelerates the flat electrode elements (1) in order to increase their distance, in particular to the processing distance.

Images