Sorting planar objects for the production of galvanic cells

Abstract

The invention relates to the sorting of planar objects that are used to produce galvanic cells, in particular electrochemical energy stores or electrochemical energy transducers. In the process, planar objects are transported along a transport path to at least two intermediate stations, said transport path branching in such a way at at least one branching device that the planar objects can be selectively transported to a first or second intermediate station. In order to sort the planar objects, the following steps are carried out in each case: - providing at least one object property of the respective planar object, and - selecting one of the intermediate stations for the respective planar object depending on the object property / properties of the respective planar object, in order to assign the respective planar object to the selected intermediate station, and - transporting the respective planar object along the transport path to the selected intermediate station, with the respective planar object being guided to the selected intermediate station by the branching device.

Description

[0001] Sorting of flat objects for the production of galvanic cells

[0002] The invention relates to a method and a device for sorting flat objects for the production of galvanic cells, e.g. electrochemical energy storage devices or electrochemical energy converters.

[0003] Flat objects such as electrodes or monocells are used to produce electrochemical energy storage devices such as batteries or energy converters such as fuel cells.

[0004] In a production line for the manufacture of lithium or sodium-ion batteries for electrically powered vehicles, e.g., pouch cells, anodes and cathodes are typically placed alternately on top of each other, separated by separators. The electrodes can be stacked on top of each other by z-folding or by stacking the electrodes or monocells made from electrodes. At the end of the production line, a multitude of the stacked electrodes are placed in a casing, which is then filled with an ion-conductive electrolyte and sealed.

[0005] In a preliminary process for the production of electrochemical energy storage devices or converters, flat objects, such as electrodes, are typically produced by separating individual flat objects from a long web of material. These flat objects are then further processed in a production line for electrochemical energy storage devices or converters.

[0006] It is known that defective flat objects are removed from the production line so that they are not further processed into electrochemical energy storage devices or converters in production.

[0007] However, it has been found that those flat objects that are further processed in the production line, despite nominally identical manufacturing conditions, have different mechanical and electrical properties, which lead to considerable quality variations in the finished electrochemical energy storage devices or converters. Since end products with the tightest possible tolerances are desired, significantly different mechanical or electrical properties between several flat objects installed in an electrochemical energy storage device or converter can lead to the finished electrochemical energy storage device or converter not meeting the requirements during final production inspection and then having to be rejected. This results in rejects in production. Since the quality and tolerance requirements for electrochemical energy storage devices or converters are constantly increasing, the reject rate also increases.the proportion of finished electrochemical energy storage or conversion devices that must be discarded to achieve a desired minimum quality.

[0008] To avoid significant quality fluctuations in the flat objects, efforts are being made to improve the pre-process for the production of the flat objects. However, there are tolerances in the starting material and the processing, which can hardly be reduced or only through complex processing optimization.

[0009] For example, the requirements for the geometric tolerances of a battery stack with regard to its external dimensions and for the relative position of electrodes or separators contained in the battery stack are increasing. Depending on the process step in the manufacture of the battery stack, these requirements can only be met with considerable effort, are hardly achievable due to the principle, or the supplied material must be accordingly available and meet the higher requirements for processing in the respective process step. If this is not successful, the number of batteries rejected during production increases because they do not meet the increased requirements. One object of the invention is therefore to provide a method and / orto specify a device which makes it possible to reduce the rejects and / or quality fluctuations of galvanic cells, in particular electrochemical energy storage devices or converters, during the production of galvanic cells, in particular electrochemical energy storage devices or converters.

[0010] 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.

[0011] A first aspect of the invention relates to a method for sorting flat objects used for the production of galvanic cells, in particular electrochemical energy storage devices or converters. In the method, a plurality of flat objects are transported individually one after the other along a transport path to at least two intermediate stations with the aid of at least one transport device. At least one branching device is arranged along the transport path, at which the transport path branches such that the flat objects can be transported selectively to a first of the intermediate stations or to at least one further of the intermediate stations. To sort the flat objects, the following steps are performed for each flat object:

[0012] - Providing at least one object property of the respective planar object and assigning the object property to the respective planar object, and

[0013] - Selecting one of the intermediate stations for the respective planar object depending on the object property(ies) of the respective planar object in order to assign the respective planar object to the selected intermediate station,

[0014] - Transporting the respective flat object along the transport path to the intermediate station selected for the respective flat object, wherein the respective flat object is guided by the branching device to the intermediate station selected for the respective flat object.

[0015] The planar objects are therefore sorted depending on the respective object property(ies) of the respective planar object.

[0016] By sorting the planar objects into different intermediate stations based on their object properties, the planar objects that match the planar objects already located there, or those whose object properties complement or compensate for the object properties of the planar objects already located there, are transported to the intermediate stations. In the first case ("match"), sorting can, for example, ensure that for each intermediate station considered, the object properties of the objects transported to the respective intermediate station vary less than the object properties of the planar objects before sorting.

[0017] For example, this can achieve a more consistent quality of the flat objects transported to or collected from the respective intermediate station. In the second case (supplement / compensate), sorting can be used to achieve a requirement for a specific stacking property of a stack of flat objects formed from the flat objects in a stacking device at the intermediate station, or to maintain tolerances for a stacking property.

[0018] Since the respective (e.g. unsuitable) flat object (e.g. electrode, monocell) can be sorted into a suitable intermediate station or sorted out at the beginning or within the production line, and a product consisting of several flat objects (galvanic cell, e.g. battery or fuel cell) does not have to be sorted out at the end of the production line due to a single (e.g. unsuitable) flat object, less waste of finished galvanic cells is produced. For example, during sorting, relevant properties of the input material (coils, separator coil) from a previous process or an incoming goods measurement and the data of the flat objects determined during the ongoing processing of the flat objects can be used to achieve an optimized, branching-assigned stack formation. For this purpose, the collected data is assigned to the respective flat objects (e.g.Electrodes, monocells) are assigned and correlated and used to decide which stack the flat object will be fed to. The selection and distribution of the material into different material streams, taking into account the requirements and knowledge of the previous parameters and expected subsequent process steps, enables a final assignment of each flat object to a stacking device or to the flat object previously placed in the stacking device. If, for example, the cathode of the last monocell placed on top is off-center / twisted, it is advantageous to place a new monocell whose anode is off-center / twisted in the same direction or orientation.

[0019] Based on the collected data of the respective flat object and the knowledge of the requirements resulting from the further processing and the permissible values ​​of each material stream (including the previous object), it is also possible to sort out the respective flat object at an early stage. For example, if the material could not meet the requirements of one of the various material streams during further processing or if the object does not meet the requirements, it can be sorted out of the production line at the earliest possible time.

[0020] A second aspect of the invention relates to a device for sorting flat objects used for the production of galvanic cells, in particular electrochemical energy storage devices or converters. The device comprises at least two, in particular two or more than two, intermediate stations, one or more transport devices designed to transport a plurality of the flat objects one after the other along a transport path to the intermediate stations, at least one branching device arranged on the transport path, at which the transport path branches such that the flat objects can be transported along the transport path selectively to a first of the intermediate stations or to at least one further of the intermediate stations, a selection device which, for the flat objects, has at least one object property of the respective flat object and which is designed todepending on the object property(ies) of the respective planar object, to select one of the intermediate stations for the respective planar object in order to assign the respective planar object to the selected intermediate station, and wherein the selection device or a control device connected to the selection device for sorting the planar objects is designed to control the at least one branching device such that the respective planar object is guided by the branching device to the intermediate station selected for the respective planar object in order to transport it along the transport path to the selected intermediate station.

[0021] An assignment of the respective object properties to the respective objects can be stored in the selection device, e.g. in the form of a table. In particular, the selection device can be designed to receive at least one object property of the respective flat object provided externally to the respective flat object (e.g. transmitted by a sensor device or by a pre-process device) and to assign it to the respective flat object. The information received externally can, however, also already contain the assignment for which of the flat objects the transmitted object property(ies) apply, e.g. if an object property is already known from a pre-process. The selection device and, if applicable, also the control device can have a processor which executes a corresponding computer program to carry out the aforementioned steps.

[0022] Flat objects

[0023] The device according to the invention / the method according to the invention is a device / method for sorting flat objects for the production of galvanic cells. These can be flat objects for the production of galvanic cells, in particular electrochemical energy storage devices, in particular batteries, or electrochemical energy converters, in particular tertiary cells, such as fuel cells.

[0024] The term "battery" is generally used as a generic term for primary cells and secondary cells. The flat objects can be battery elements for producing a primary cell or a secondary cell. For example, the battery elements are monocells, bicells, individual electrodes such as anodes or cathodes, or anode-separator combinations, cathode-separator combinations, or anode-separator-cathode-separator combinations.

[0025] The flat objects can also be fuel cell elements, such as fuel cell electrodes (fuel cell anodes or fuel cell cathodes) or combinations of fuel cell anodes and / or fuel cell cathodes and other objects (e.g. membranes or plates) or individual fuel cell units (several of which are connected together to form a fuel cell).

[0026] The flat objects can also be battery elements or fuel cell elements, in particular electrodes that are coated and / or arranged on a carrier.

[0027] The flat objects to be sorted preferably originate from one of the several pre-processes used to produce the flat objects. The multitude of flat objects to be sorted can originate from a common pre-process used to produce the flat objects and can accordingly be a multitude of similar elements, e.g., monocells or electrodes. However, the sorting process can also be used to sort different types of flat objects, e.g., cathodes and anodes, from which monocells are produced during or after sorting.

[0028] stopover

[0029] In particular, flat objects can be collected in the intermediate station for further processing into galvanic cells, e.g., electrochemical energy storage devices or converters. For example, the intermediate stations each have a stacking device for the flat objects, e.g., a stacker wheel with a storage device for the flat objects, a z-folding device, or a laminating device, or are connected to one of these devices.

[0030] The intermediate stations are not reject or waste stations. They are components of a production line for galvanic cells, in particular electrochemical energy storage devices or converters, such as batteries or fuel cells. In particular, the intermediate stations / each of the intermediate stations / the first and second intermediate stations are each integrated into the production line for galvanic cells in such a way that the flat objects transported to the intermediate station (in the intermediate station or in a further processing station following the intermediate station in which the flat objects are further processed, e.g. in a further processing station of the production line following the intermediate station) are processed into galvanic cells, in particular electrochemical energy storage devices or converters, e.g. batteries or fuel cells.

[0031] In preferred embodiments, at least two intermediate stations each have a stacking device for the flat objects, which is designed to deposit the flat objects transported to it along the respective transport path onto a stack receptacle (e.g., storage shelf) of the respective stacking device in order to stack them there on a stack comprising a plurality of the flat objects. The stacking device can have a pick-and-place robot or a stacker wheel. In the stacking device, the flat objects can be stacked alternately with other flat stack objects (e.g., electrode and counterelectrode, electrode and separator) to form the stack. However, several similar objects can also be stacked to form the stack, e.g., monocells or similar electrodes (anodes or cathodes).

[0032] Alternatively, the intermediate station can also be a further processing station for individual flat objects without collecting or stacking them there, e.g., where the flat objects are further treated or processed in another way. For example, the intermediate station can be designed to apply a coating to the individual flat objects (e.g., electrodes) transported to the intermediate station.

[0033] Branching device The branching device is designed to switch the transport path of the flat objects between two or more than two intermediate stations such that the flat objects transported along the transport path to the branching device can be guided selectively to one or the other intermediate station by the branching device. The branching device has, for example, at least two positions between which it can be switched, wherein the branching device guides the flat objects transported along the transport path to the branching device to the first intermediate station in a first position of the branching device and to one or more other intermediate stations in a second position of the branching device.

[0034] If different intermediate stations are selected for two consecutive flat objects along the transport path, the branching device is switched between the respective flat objects in order to guide the respective flat object transported along the transport path through the branching device to the intermediate station selected for the respective flat object. If the same intermediate station is selected for the two flat objects, the branching device between the two flat objects can be left in its position. The branching device can, for example, comprise one or more transport switches.

[0035] Sorting out

[0036] Optionally – in addition to the sorting described – flat objects that do not meet certain minimum requirements can be sorted out, e.g. by a pre-sorting device arranged along the transport path upstream of the branching device. This has, for example, a transport diverter via which unsuitable flat objects can be sorted out of the transport path into a reject container. Only the flat objects that remain on the transport path after the pre-sorting are reused in production, in particular transported further to the branching device(s) and / or to the intermediate stations. Preferably, the sorting is carried out by a pre-sorting device arranged upstream of the at least one branching device.However, the sorting can also be carried out by a sorting device arranged at the end of the transport route, after the branching device(s).

[0037] The decision as to which flat objects are to be sorted out can be made based on information from the previous process or a previously known material property.

[0038] The pre-sorting device can be arranged downstream of a sensor device (described in more detail below). The decision as to which flat objects are to be pre-sorted can then be made based on the measurement data from the sensor device, possibly also taking into account information from the previous process or a previously known material property. However, the pre-sorting device is preferably arranged along the transport path upstream of the aforementioned sensor device. This eliminates the need to measure pre-sorted flat objects unnecessarily with the sensor device.

[0039] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described for sorting, e.g. have a processor which executes a corresponding computer program.

[0040] Object properties used for sorting The object property of the respective flat object, depending on which the flat objects are sorted, can be determined from measurement results of a sensor device arranged on the transport path of the flat objects and made available for sorting or it can be transmitted by an external device and made available for sorting, such as a previously known material property of the flat objects or an object property determined from measurement results of a previous process.

[0041] Examples of the object property(ies) used for sorting are:

[0042] - geometric properties of the flat object, e.g. geometric dimensions such as length, width, thickness of the flat object; angular deviations; parallelism of the edges; straightness of the cutting edges; surface area of ​​the flat object; a relative position of two sub-elements of the flat object (e.g. position of the electrode on a carrier),

[0043] - Positional tolerances and deviations of the flat object, e.g. displacement and rotation of an electrode on the separator or the position of the electrodes within a monocell,

[0044] - Quality information (Q-sorting), e.g. quality of the cut edges,

[0045] - Material properties of the flat object, e.g. homogeneity, porosity, the number, type or properties of defects or faults of the flat object,

[0046] - the electrical property of the flat object (e.g. electrical voltage or electrical resistance or conductivity or electrical capacitance).

[0047] The one or more object properties used for sorting can already be known before sorting begins. In particular, a previously known material property of the respective flat object and / or an object property of the respective flat object determined in a preliminary process of the sorting method can be made available and assigned to the respective flat object. The material property or object property determined from the preliminary process can apply and be made available individually for the respective flat object or for a group of flat objects. For example, information about the material quality or one or more dimensions of the respective flat object or of a production batch of flat objects can be made available and assigned to the individual flat objects.

[0048] Alternatively or additionally, one or more (individual) object properties used for sorting can be determined using a sensor device. The sensor device is designed to perform one or more measurements, based on which the respective object property can be determined individually for the respective flat object and thus made available for sorting.

[0049] In particular, the flat objects can be transported one after the other along the transport path by means of a transport device past the sensor device, which is arranged along the transport path upstream of the at least one branching device. To determine the at least one individual object property, the sensor device detects at least one measurement signal of the respective flat object, e.g., while the flat object is being transported past. Based on the measurement signal detected for the respective flat object, it then determines at least one individual object property of the flat object.

[0050] The sensor device can be designed to detect at least one measurement signal of the respective flat object, e.g., while the respective flat object is being transported past the sensor device, and to determine at least one of the object properties of the flat object based on the measurement signal detected for the respective flat object and to make it available to the selection device of the apparatus. Preferably, the sensor device is designed to perform one or more measurements on the basis of which one or more of the aforementioned individual object properties can be determined. The sensor device can assign the individual object properties to the respective flat object and transmit the individual object properties with this assignment to the selection device.

[0051] Alternatively or additionally, information about object properties of individual or multiple planar objects, possibly also individual object properties of the respective planar object, can be made available to the selection device by a device external to the device.

[0052] Sorting criteria and sorting classes

[0053] When selecting the intermediate station / stacking device, the at least one object property provided for the respective flat object can be checked - individually for each flat object - against at least one sorting criterion. The flat objects are assigned to different sorting classes depending on whether the respective flat object fulfills the at least one sorting criterion. For example, in a first step, the flat object can be assigned to one of the sorting classes (predefined sorting classes or a sorting class defined by the object property itself) based on the at least one object property specified for the respective flat object, and in a second step, it can be assigned to one of the intermediate stations / stacking devices based on the sorting class.

[0054] When checking based on at least one sorting criterion, a test result can be generated that indicates whether the object property(ies) of the respective flat object meet(s) the respective sorting criterion. The intermediate station for the respective flat object is then selected depending on the test result. For example, a first intermediate station / stacking device can be selected for the respective flat object if the test result is that the object property(ies) meet(s) the respective sorting criterion, and a second intermediate station / stacking device can be selected if the test result is that the object property(ies) do not meet the respective sorting criterion.

[0055] The sorting criteria and / or sorting classes can be predefined. For example, a predefined sorting criterion involves comparing the respective object property (e.g., one of the object properties mentioned above) with one or more predefined thresholds corresponding to minimum or maximum values. Alternatively, the sorting criteria and / or sorting classes can be determined or adjusted dynamically, which is explained in more detail below. Some of the sorting criteria and / or sorting classes can also be predefined and others determined or adjusted dynamically.

[0056] It can be a single object property that is checked against one or more sorting criteria. However, multiple object properties can also be checked against multiple sorting criteria in order to determine an overall test result for multiple object properties of the planar object, which is determined depending on which sorting criteria are met for the planar object and which are not. The overall test result then contains information about multiple sorting criteria, which sorting criteria the object properties of the respective planar object meet and which are not. The advantage of an overall test result for multiple object properties and multiple sorting criteria is that it enables an overall assessment of the planar object.

[0057] For example, the suitability of flat objects for the production of galvanic cells can be assessed from several perspectives. For a positive overall test result for the flat object, the respective sorting criteria must be met. For example, it may be required that the dimensions must be within specified limits and the electrical resistance within specified limits. Otherwise, as soon as one of the sorting criteria is not met, a negative overall test result is generated for the flat object, and the flat object is sorted differently or rejected accordingly.

[0058] The intermediate stations / stacking devices can be assigned to different sorting classes or can be assigned during the sorting process.

[0059] Each intermediate station / stacking device is preferably uniquely assigned to one of these sorting classes. However, multiple intermediate stations / stacking devices can also be assigned to the same sorting class to provide sufficient capacity for the flat objects with the most frequently occurring object properties.

[0060] If, when checking the respective flat object based on at least one sorting criterion, it becomes apparent that several intermediate stations / stacking devices could be selected for the respective flat object, the sorting decision, i.e., the selection of the stacking device for the respective flat element, can be controlled based on the process, e.g., to optimize throughput through the production line or to avoid stop situations. For example, the stacking device for the respective flat object can be selected depending on the following aspects:

[0061] - based on the knowledge of the properties of the last deposited flat objects and the knowledge of the properties of subsequently incoming flat objects of the material flow,

[0062] - the completion of several stacks as evenly as possible in order to make them available for further processing at the same time,

[0063] - to complete the stacks one after the other if possible, so that the stacks can be removed for further processing one after the other,

[0064] - the correlation with other properties (deviating from the position tolerance) - the consideration of the tolerance-related storage accuracy of the stacking process

[0065] - the achievement of (other) target properties of the stack (such as a specified maximum stack height for a given number of objects). In other words, as new planar objects are deposited that must achieve a target property through summation, a successive tolerance narrowing for the additional planar objects takes place and can be taken into account during sorting.

[0066] Quality sorting classes

[0067] Preferably, several quality sorting classes are used for the flat objects. In particular, there are at least two different acceptance sorting classes within the sorting classes, and associated intermediate stations / stacking devices for those flat objects that are transported to intermediate stations / stacking devices for further processing into galvanic cells.

[0068] By sorting the flat objects into multiple quality sorting classes, it is achieved that – despite the highly fluctuating object properties of the input material or the flat objects (e.g., electrodes, monocells) – end products or galvanic cells can be manufactured with minimal quality fluctuations in the respective quality sorting class. Furthermore, multiple quality sorting classes ensure that not only high-quality flat objects, but also lower-quality flat objects (with lower requirements) can be used for the production of galvanic cells, thus eliminating the need for disposal. This reduces overall production waste.For example, there is a first acceptance sorting class for flat objects of very good quality, to which one or more first intermediate stations / stacking devices are assigned, and a second acceptance sorting class for flat objects of sufficient quality, to which one or more second intermediate stations / stacking devices are assigned. The various sorting classes for different qualities of the flat objects or stacks can, for example, relate to mechanical deviations of the flat objects, which in a first acceptance sorting class are very close to the target values, or in the second acceptance sorting class are somewhat further away from them, but are still acceptable. Preferably, there is also at least one reject sorting class among the sorting classes for those flat objects that are sorted out so that they are not used for further processing into galvanic cells.

[0069] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described with regard to the sorting criteria / sorting classes, e.g., have a processor which executes a corresponding computer program.

[0070] Sorting using the best fit method

[0071] In order to decide to which intermediate station / stacking device the respective flat object should be transported, a so-called best-fit method can be used. In this case, at least one (dynamic or predetermined) target value and / or at least one (dynamic or predetermined) value range is assigned to each of the intermediate stations / stacking devices for at least one object property, or this is assigned during the sorting process. To decide which of the intermediate stations / stacking devices is selected for the respective flat object, the corresponding object property of the respective object is compared with the at least one (dynamic or predetermined) target value or with the at least one (dynamic or predetermined) value range of several of the intermediate stations / stacking devices.Depending on the comparison results, the respective flat object is then assigned to one of the intermediate stations / stacking devices and transported there (in the case of the stacking device, stacked there).

[0072] For example, for the respective planar object, the intermediate station / stacking device is selected whose (dynamic or predetermined) target value(s) and / or whose (dynamic or predetermined) value range(s) is closest to the value of the corresponding object property of the planar object, and the respective planar object is assigned to the selected intermediate station / stacking device and transported there (in the case of the stacking device, stacked there).

[0073] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described for the best-fit method, e.g., have a processor that executes a corresponding computer program.

[0074] Sorting taking into account a stack property

[0075] If the intermediate stations each have a stacking device for stacking the flat objects, these stacking devices can

[0076] - a stack target value / stack target range for a stack property (e.g. for the stack thickness or for the electrical voltage / resistance of the stack as a whole) of a stack of flat objects to be formed in the respective stacking device is or will be specified, and

[0077] - for the flat objects already stacked in the respective stacking device, an actual value for the relevant stacking property is determined during sorting (dynamically, e.g. regularly after one or more flat objects), e.g. based on the measurement results or advance information on these flat objects, and

[0078] - based on the stack target value / stack target range predetermined for the stack property and the actual value determined for the stack property, it is examined whether the stack with the actual value is likely to reach the stack target value / stack target range or not after placing further flat objects (with expected, e.g. average, value of the object property) on the stack.

[0079] In the event that the actual value is not expected to reach the stack target value / stack target range of the stack property in question, those flat objects can be specifically selected for the stacking device in question and stacked there whose object property changes the actual value in such a way that the actual value approaches the stack target value / stack target range.

[0080] For the other planar objects whose object properties would not bring the actual value close to the stack target value / stack target range, another stacking device is selected and these are stacked there (e.g. a new stack is started) or these other planar objects are sorted out.

[0081] The stacking property of each stack results from the object properties of the planar objects in the stack. For example, the value of the stacking property corresponds to a (mathematical) summation (e.g., summing, averaging, weighting) of the object property values ​​of all planar objects in the respective stack. The stacking property affects, for example, the stack height, the electrical voltage, or the electrical resistance / conductivity of the stack.

[0082] The investigation of whether the stack, with the actual value, is likely to reach the stack target value / stack target range after additional flat objects are placed on the stack can be carried out, for example, using statistical methods that take into account a probability distribution of the values ​​of the respective object properties. The actual value of the stack already deposited in the stacking device can also be extrapolated based on the number of flat objects still to be deposited on the stack and based on an expected object property (e.g., expected / average thickness or stress), and the extrapolated value can be compared with the stack target value / stack target range of the stack property.If this exceeds or falls below the stack target value / stack target range (actual value too large / small), flat objects with a lower / larger value of the respective object property (thickness, voltage) are preferentially placed on the respective stack in order to compensate for the actual value that is too large / too small.

[0083] For example, one or more suitable planar objects can be selected as the final object(s) of the stack so that a certain stacking property of the stack as a whole is achieved, e.g. a certain total height or a certain electrical property of the stack as a whole.

[0084] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described (with regard to the sorting taking into account the stacking property), e.g. have a processor which executes a corresponding computer program. depending on the highest one

[0085] Alternatively or additionally, the decision as to which of the stacking devices is selected for the respective flat object can be made for one or more flat objects depending on the object properties of one or more uppermost flat objects that are currently placed on top of the stacks in the stacking devices. For example, a dynamic target value / value range of at least one object property can be assigned to at least one stacking device, which is selected depending on the value of the corresponding object property of the uppermost flat object of the stack placed in the stacking device. A subsequent flat object is only assigned to the respective stacking device and stacked on top of the uppermost flat object if its value of the object property at least approximately corresponds to the dynamic target value orwhose object property value lies within the dynamic value range. Otherwise, if the object property value does not correspond to the dynamic target value / value range, the subsequent flat object is assigned to a different stacking device and transported there, or it is sorted out.

[0086] The object property of the flat object placed on top of the respective stack, depending on which the sorting decision is made, can be provided by the above-mentioned pre-processing device or by the above-mentioned sensor device or by another sensor device arranged on the stacking device, which detects the top flat object of the stack currently located in the stacking device, e.g. its position on the stack (e.g. offset or rotation).

[0087] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described (with regard to the sorting depending on the uppermost flat object), e.g. have a processor which executes a corresponding computer program.

[0088] Dynamic sorting classes Of the sorting classes used during sorting, one or more sorting classes can be determined dynamically, i.e. at least one sorting criterion of the sorting class is not yet determined before the start of sorting of the flat objects, but is only determined after the start of sorting of these flat objects, in particular after one or more first flat objects have been transported to the respective intermediate station / stacking device. This intermediate station / stacking device is then assigned a dynamic sorting class, i.e. a sorting class that is defined / selected depending on the object property(ies) of this first flat object. At least some of the flat objects, in particular one or more flat objects following the first flat object, can then be assigned to this dynamic sorting class and transported to the intermediate station / stacking device assigned to it.For the sorting criterion that has not yet been defined before sorting begins, a default value or range can be assumed before sorting begins, which is then overwritten or defined more precisely depending on the object property(ies) of the first planar object in order to determine the sorting criterion.

[0089] For example, the sorting criteria of the dynamic sorting class can only be determined after the first several flat objects have been transported to the respective intermediate station / stacking device. For example, due to a surprisingly large number of flat objects that do not meet the sorting criteria, the limits of the affected sorting criterion can be extended to allow a greater tolerance for a stack that has already been partially formed than originally intended. This has the advantage that the affected flat objects do not have to be sorted out subsequently, but can be used to create a (lower quality) stack. Analogously, if the affected sorting criterion is unexpectedly exceeded by the flat objects, the limits of the affected sorting criterion can be set more narrowly (i.e. tightened) in order to create a higher quality stack from the affected flat objects.

[0090] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described (with regard to the dynamic sorting classes), e.g., have a processor which executes a corresponding computer program.

[0091] Dynamically selected stacking device

[0092] In an intermediate station with a stacking device for stacking flat objects, after the respective stacking device has stacked a stack with a plurality of flat objects on a stack and the stack is finished, the finished stack can be removed from the respective stack holder of the stacking device in order to transport it to a further processing station following the stacking device and to make the stack holder of the respective stacking device ready to receive a new stack.At least one of these stacking devices can be a dynamically selected stacking device, in which, after the respective stacking device has been prepared to receive a new stack (when none of the flat objects are temporarily located on the stacking device's stacking receptacle), one or more first flat objects are assigned to the dynamic stacking receptacle thus provided in order to stack them there. The assignment of the first flat objects to the dynamic stacking device can be random or dependent on object property(ies) of the first flat objects, e.g., if they do not match any sorting class of the other stacking devices.After the first flat objects have been assigned to the dynamic stacking device, the decision as to which of the stacking devices is selected for the respective subsequent flat object can be made for one or more subsequent flat objects that follow the first flat objects along the transport path, depending on the object properties of the first flat object(s) that the dynamic stacking device has already deposited on the stack holder of the dynamic stacking device (which is / are currently located on the stack holder of the dynamic stacking device (stack is not yet fully formed). For example, with the object property position or rotation of the electrode relative to the carrier, it is preferred that subsequent flat objects with a similar rotation are subsequently deposited on the same stack onto a first flat object that has such a rotation.

[0093] In a stack, the requirements between two adjacent planar objects of the stack can be more tightly tolerated than the requirements for the stack as a whole, for example, when covering a cathode lying on the stack with the next incoming anode.

[0094] When depositing the first object of a new stack, it may be useful to specify additional requirements at the beginning of a new stack to reduce the number of flat objects to be sorted out, as this first object defines, influences, or even restricts the target properties of the respective stacking device. Examples: the various stacks should, if possible, cover the entire spectrum of all currently occurring deviations.

[0095] - Untypical, more restrictive first flat objects are better used to complete a stack rather than as the starting object for a new stack, or the flat object in question is better sorted out. Likewise, process-related requirements for material flow can influence whether it is better to continue filling a stack, complete a stack, or start a new one. If, for example, the subsequent process requires the completed stacks to be synchronized as evenly as possible, it may be preferable to complete a stack, continue filling another stack, or start a new stack instead.

[0096] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described (with respect to the dynamically selected stacking device), e.g., have a processor which executes a corresponding computer program.

[0097] Dynamically selected target values ​​or value ranges

[0098] The dynamically selected stacking device to which the first planar object(s) was / are assigned can be assigned at least one dynamic target value / value range of at least one object property, which is selected depending on the value of the corresponding object property of the first planar object(s). The value of the object property of the first planar object or a value of the object property that is representative of several first planar objects can be selected as the dynamic target value, e.g. their mean value. The dynamic value range can be selected such that it includes the value of the object property of the first planar object(s), e.g. + / - 10% around the value of the object property of the first planar object(s). One or more subsequent planar objects whose value of the object property at least approximately corresponds to the dynamic target value orObjects whose object property value lies within the dynamic value range can also be assigned to this dynamically selected stacking device and stacked on top of the first flat objects. Otherwise, if the value of the object property does not correspond to the dynamic target value or value range, the respective subsequent flat object can be assigned to a different stacking device or sorted out.

[0099] Even in the case of the dynamically selected stacking device, a comparison can be performed with dynamic and other stacking devices in accordance with the best-fit method described above. Thus, to decide which of the stacking devices is selected for the respective subsequent flat object, the corresponding object property of the respective subsequent object can be compared with the dynamic target value or the dynamic value range of the dynamic stacking device and with (dynamic or predetermined) target values ​​or (dynamic or predetermined) value ranges of other stacking devices. The respective subsequent object can be assigned to one of the stacking devices and stacked there depending on the comparison results of this comparison.For example, for the respective subsequent flat object, the stacking device is selected whose (dynamic or predetermined) target value or whose (dynamic or predetermined) value range is closest to the value of the object property of the respective subsequent object, and the respective subsequent object is assigned to the selected stacking device, transported there and stacked there.

[0100] For example, a dynamically selected stacking device to which the first planar object has been assigned can be assigned a size value range for a size of the planar object, which is selected depending on the size of the first planar object (e.g. which is selected around the size of the first planar object and includes it, e.g. as an average value + / - 10%). If there are several first planar objects, their average value + / - 10% can be used as the value range. For example, a dynamic angle target value can be assigned for the rotation of the electrode relative to the electrode carrier of the stacking device, which is selected depending on the rotation of the first electrode.

[0101] For the position shift of the electrode relative to the electrode carrier, the stacking device can be assigned a dynamic value range, which is selected depending on the position shift of the first electrode.

[0102] If the respective flat object could be assigned to several stacking devices due to its object property(ies), the decision can be made in such a way that the flat objects are distributed as evenly as possible among the stacking devices.

[0103] In the device according to the invention, the selection device of the device (and optionally the control device of the device) can be designed to carry out the steps described (with regard to the dynamically selected target values / value ranges), e.g., have a processor which executes a corresponding computer program.

[0104] In some embodiments, the transport path branches at the branching device into at least two transport branches, each leading to one of the intermediate stations, wherein the flat objects in the transport branches can be transported to the respective intermediate station (with the aid of the transport device or with the aid of another transport device of the respective transport branch). The flat objects are transported in the transport branches to the respective intermediate station, in particular a stacking device, in particular with the aid of the transport device or with the aid of another transport device of the respective transport branch. For example, each transport branch leads to a different one of the intermediate stations / stacking devices.

[0105] The respective planar object transported along the transport path can be sorted by the at least one branching device into a selected transport branch of the transport branches, which leads to the intermediate station selected for the respective planar object, so that the respective planar object is transported along the selected transport branch to the selected intermediate station.

[0106] The advantages presented with reference to the method according to the invention apply accordingly to the device 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:

[0107] Fig. 1 A first embodiment of a device for sorting flat objects,

[0108] Fig. 2 shows a second embodiment of a device for sorting flat objects,

[0109] Fig. 3 shows an embodiment of sorting into several stacks depending on the days of an electrode on a carrier,

[0110] Fig. 4 schematically shows the sorting of flat objects into several stacks based on various possible sorting criteria,

[0111] Fig. 5 shows an overview of the process steps in monocell production up to the sorting of the monocells.

[0112] Figure 1 shows a first exemplary embodiment of a section of a production line for galvanic cells, e.g., fuel cells or battery cells, with a device 10 for sorting flat objects for the manufacture of the galvanic cells. A pre-processing device 40 is located upstream of the sorting device 10 in the production line, which pre-processing device provides a plurality of individual flat objects i for the manufacture of galvanic cells. In the exemplary embodiment shown, the flat objects are transported from the pre-processing device 40 to the sorting device 10. The flat objects are components of fuel cells or battery cells.

[0113] In the sorting device 10, the flat objects i are transported by means of a transport device 2 along a transport path 5 (arrow in the transport direction) to a branching device 6. The branching device can be a transport switch 6 that can be switched between a lower position and an upper position in order to transport the flat objects i optionally either to an intermediate station 4a or to an intermediate station 4b. Between the branching device 6 and the intermediate stations 4a, 4b, the flat objects i are transported in the transport branch 5a to the upper intermediate station 4a by means of a further transport device 2a and in the transport branch 5b to the lower intermediate station 4b by means of a further transport device 2b. The transport devices 2, 2a, 2b have, for example, transport rollers and / or conveyor belts that rotate around rollers on which the flat objects are transported lying down.Opposing pairs of transport rollers or opposing conveyor belts can be used, between which the flat objects are clamped. Suction plates, suction belts, or suction drums can also be used as transport devices for the flat objects.

[0114] The intermediate stations 4a, 4b are each designed to stack the flat objects i onto a stack 7a or 7b. For example, they have a stacking device for this purpose, e.g., a pick-and-place robot or a stacker wheel, see Fig. 2. The stacks 7a or 7b of flat objects i formed in the intermediate stations 4a or 4b are then transported, e.g., stack by stack, to a further processing station 20a or 20b of the production line, which further processes the stacks 7a or 7b to manufacture battery cells or fuel cells. For example, the flat objects of a first acceptance sorting class A1, which corresponds to a high quality and whose flat objects are used to manufacture high-quality galvanic cells, are transported to the intermediate station 4a and then to the further processing station 20a.And to the intermediate station 4b and then to the further processing station 20b, the flat objects of a second acceptance sorting class A2 are transported, which does not correspond to the high quality and whose flat objects are used for the production of normal galvanic cells.

[0115] The sorting of the flat objects i to the upper or lower intermediate station 4a or 4b is carried out based on object properties of the flat objects i, which are made available to a selection device 8a for sorting. For example, the selection device 8a has a data memory 81 in which one or more values ​​Pi of one or more object properties are contained for each flat object i (e.g. in the form of a table). Depending on the object property(ies) of the respective flat object, the selection device 8a selects one of the intermediate stations 4a, 4b for the respective flat object in order to assign the respective flat object to the selected intermediate station 4a or 4b. In order to select the intermediate station suitable for the flat object, an evaluation device 82 of the selection device 8a evaluates the information about its object property(ies).For example, the evaluation device 82 checks the at least one object property determined for the respective flat object based on at least one sorting criterion and assigns the flat objects to different sorting classes (e.g., the aforementioned acceptance sorting classes A1, A2) depending on whether the respective flat object fulfills the at least one sorting criterion. A control device 8b connected to the selection device receives the information about the selected intermediate station from the selection device and, based thereon, adjusts the branching device 6 such that the respective flat object is guided by the branching device 6 to the intermediate station selected for the respective flat object in order to transport it along the transport path 5a or 5b to the selected intermediate station 4a or 4b.If successive flat objects i have to be guided to different intermediate stations 4a, 4b, the control device 8b switches the branching device 6 between the two flat objects accordingly.

[0116] In order to additionally provide individual object properties of the planar objects i, the device 10 has a sensor device 9 arranged along the transport path upstream of the branching device 6. The sensor device 9 detects at least one measurement signal of the respective planar object as it is transported past the sensor device, determines at least one individual object property of the planar object based on the detected measurement signal, and makes this available to the selection device 8a.

[0117] Alternatively or additionally, an external device 30 can transmit information about object properties of several individual planar objects or about individual object properties of the respective planar object i to the selection device 8a. These object properties include, for example, a previously known material property of the respective planar objects of a specific production batch or an object property determined in a preliminary sorting process that is already assigned to the respective planar object.

[0118] In the first embodiment of Fig. 1, the flat objects are transported by means of at least one further transport device of the selected transport branch (from the branching device) to the selected intermediate station, in particular stacking device.

[0119] Figure 2 shows a second embodiment of a device 10 for sorting flat objects for the production of galvanic cells. As in the first embodiment, the sorting device 10 is also preceded by a pre-process device 40, which generates a plurality of individual flat objects i and prepares them for a production line for the production of galvanic cells, which are transported to the sorting device 10. In the second embodiment of Fig. 2, the branching device 6a guides the flat objects (without any further transport device in between) in one position directly to an intermediate station 4a and in the other position to a further transport device, which transports the flat objects in the direction of the other branching device 6b, c or intermediate stations 4b.c.

[0120] In the sorting device 10, the flat objects i are transported along the transport path 5 by means of a transport device 2. The device 10 has a plurality of sensors 9, 19 along the transport path 5 (arrow in the transport direction of the flat objects i), which - like the sensor device 9 described above - make individual object properties of the flat objects i available to the selection device 8. For example, the sensor device 9 can be designed to measure electrical properties of the flat objects, e.g. their electrical voltage or their electrical resistance. For example, the sensor device 19 can be designed to detect the geometric position of the edges of the flat objects in order to detect the geometric dimensions and / or the shape and / or a transport offset and / or an inclined position of the flat object. For this purpose, the sensor device 19 can have a camera or a line of light barriers.In the sorting device 10, the flat objects i are first transported along the transport path 5 to the transport diverter 16 of a pre-sorting device, which is arranged along the transport path upstream of the branching devices 6a-c and upstream of the sensors 9, 19. The pre-sorting device 16 sorts out those flat objects that do not meet certain minimum requirements. For this purpose, the pre-sorting device has a transport diverter 16, via which unsuitable flat objects can be sorted out of the transport path into a reject container 17. Only the flat objects i that are transported further along the transport path 5 after the pre-sorting are reused in production.

[0121] A transport diverter 61 of a further pre-sorting device can be arranged along the transport path downstream of the sensors 9, 19. Using the further pre-sorting device 61, flat objects can be sorted into a further reject container 20 for which it is determined, based on measurement signals from the sensor devices 9 and / or 19, that they do not meet certain sorting criteria necessary or desired for production and are therefore assigned to a reject sorting class.

[0122] The individual object properties of the flat objects i made available to the selection device 8 by the sensor devices 9, 19 are used by the selection device 8 to select the appropriate intermediate station for the flat object. For example, the evaluation device 82 checks the at least one object property determined for the respective flat object using at least one sorting criterion and assigns the flat objects to different sorting classes depending on whether the respective flat object fulfills the at least one sorting criterion. Examples of this are explained in more detail below. The selection device 8 sets the branching devices 6a, 6b, 6c based on the selection made such that the respective flat object is guided by the branching device to the intermediate station selected for the respective flat object in order to transport it to the selected intermediate station 4a or 4b or.4c. If consecutive flat objects i need to be guided to different intermediate stations 4a, 4b, 4c, the selection device 8 switches the branching device 6a and / or 6b and / or 6c between the two flat objects accordingly. The branching devices can be designed analogously to the transport switch 6.

[0123] By means of the branching device 6a, the flat objects i can be selectively directed either to the intermediate station 4a or transported toward the intermediate stations 4b, 4c. Accordingly, the flat objects can be selectively directed either to the intermediate station 4b or transported toward the intermediate stations 4c by means of the branching device 6b, and can be selectively directed either to the intermediate station 4c or transported further along the transport path 5, e.g., to further intermediate stations, by means of the branching device 6c.

[0124] The intermediate stations 4a, 4b, 4c are each designed to stack the flat objects i onto a stack 7a, 7b, or 7c, respectively, and for this purpose each have a stacker wheel 41, see Fig. 2. The stacker wheels 41 are each rotatable about a stacker wheel axis and have a plurality of stacker wheel compartments, each designed to receive a flat object. The stacker wheel compartments are formed between stacker wheel fingers of the stacker wheel, which are distributed over the circumference of the stacker wheel. The stacker wheel is rotated about the stacker wheel axis by means of a motor such that a flat object i is inserted into a stacker wheel compartment of the respective stacker wheel 41 by means of the transport device. By means of a stripper (cf. Fig. 2), the flat object i received in the respective compartment is stripped out of the stacker wheel 41 in order to place it on a shelf 42 and there to form a stack of flat objects 7a or 7b or 7c.The forklift wheel fingers and compartments run spirally around the axis of rotation, but can also be straight, e.g. radial, and may have a larger compartment width than shown.

[0125] The stacks 7a-c of flat objects formed in the intermediate stations 4a-c are then transported to a further processing station 20a, 20b, or 20c of the production line, which further processes the stacks 7a, 7b, or 7c to produce battery cells or fuel cells. For example, the flat objects of a first acceptance sorting class A1, which corresponds to a high quality and whose flat objects are used to produce high-quality galvanic cells, are transported to the intermediate station 4a and then to the further processing station 20a. The flat objects of a second acceptance sorting class A2, which does not correspond to the high quality and whose flat objects are used to produce normal galvanic cells, are transported to the intermediate stations 4b and 4c and then to the further processing stations 20b and 20c.

[0126] A third embodiment is analogous to the second embodiment with the difference that the device 10 of the third embodiment does not have any of the pre-sorting devices 16, 61.

[0127] A fourth embodiment is analogous to the second embodiment with the difference that the device 10 of the fourth embodiment does not have any pre-sorting devices 16 and the sorting device 61 is arranged along the transport path not before, but after the intermediate stations 4a-4c (dashed line on the right in Fig. 2).

[0128] A fifth embodiment is analogous to the first embodiment, with the difference that the device of the fifth embodiment does not have a sensor device 9, but uses the information from the pre-process device 40 for sorting.

[0129] Examples A)-D) of possible sorting variants

[0130] A) In a first sorting variant, the flat objects are sorted into different intermediate stations (e.g. stacking devices) only depending on the object properties known from a previous process.

[0131] For example, due to the current production process—due to a different production batch—the pre-process device 40 may announce before sorting that smaller electrodes / monocells will be fed into the sorting process at a certain point in time than previously. Therefore, during sorting, a new stack is started for the smaller electrodes / monocells, onto which only smaller electrodes / monocells are subsequently stacked. All larger electrodes / monocells are directed to another stacking device and stacked there on top of a stack of larger electrodes / monocells.

[0132] B) In a second sorting variant, the flat objects are sorted into different intermediate stations (e.g. stacking devices) depending on the object properties, which are determined by one or more sensors located in front of the branching device of the sorting device.

[0133] For example, the flat objects are sorted into various intermediate stations (e.g., stacking devices) depending on the geometric dimensions measured by such a sensor and / or the relative position of two sub-elements of the flat object (e.g., the position of an electrode on a carrier) measured by such a sensor and / or the material properties measured by one of the sensors and / or the electrical quality of the objects measured by one of the sensors. If necessary, the flat objects can also be sorted depending on the object properties known from a previous process.

[0134] For the first and second sorting variants, predefined sorting classes and / or predefined sorting criteria (i.e., which object properties are assigned to the various intermediate stations / stacking devices) can be used. In this case, the sorting criteria or sorting classes are already defined before the start of sorting / stacking. For example, intermediate stations 4a, 4b, and 4c can be predefined to collect electrodes / monocells of different material qualities (e.g., with regard to defects).

[0135] C) In a third sorting variant, at least one sorting criterion or sorting class is not predefined, but is only determined after the sorting process has begun (e.g., after batch formation begins). This is referred to as a dynamic sorting criterion / dynamic sorting class.

[0136] The dynamic sorting criterion / dynamic sorting class for a planar object to be sorted can be determined or at least influenced by the sorting of one or more planar predecessor objects that were sorted / stacked before the planar object in question. In particular, the dynamic sorting criterion / dynamic sorting class for a planar object to be sorted can be determined or at least influenced by object properties of those planar objects that are stored in one or more stacks that have already been started, e.g., by the object properties of several / all planar objects or only the topmost planar object of one or more of the stacks that have already been started. The object properties that determine / influence the dynamic sorting criterion / dynamic sorting class are not known, for example, by a previous process or are not yet determined before the start of the sorting, but are, for example,only determined / influenced by the object properties of one or more flat objects determined by a sensor located upstream of the branching devices of the sorting device. For example, a dynamic sorting criterion / a dynamic sorting class can be determined by the position (e.g. offset or rotation) of the flat objects in the transport path measured by such a sensor, or by the relative position of two sub-elements of the flat object measured by such a sensor (e.g. position of an electrode on a carrier), or by the electrical quality or material properties of one or more flat objects measured by such a sensor, e.g. with regard to material defects.

[0137] For example, for a first flat predecessor object, a "free" intermediate station / stacking device is first selected in which no flat object has yet been deposited or in which a new stack of flat objects is to be started. The selection of which flat object is to be used as the first flat object for a currently free intermediate station or for a new stack can be made arbitrarily or depending on its object properties known from the previous process or measured by the sensor. The selected intermediate station / stacking device is then dynamically assigned a sorting class characterized by a target object property selected depending on the object properties of the predecessor object, e.g. a certain material quality.The sorting criteria are then dynamically changed (during or after sorting the predecessor object) so that subsequent flat objects to be sorted, which are sorted after the predecessor object and which (at least approximately) also have this target object property (e.g., material quality), are also sorted into the intermediate station / stacking device selected for the predecessor object. The target object property can also correspond to / be similar to the object properties of several predecessor objects already routed to the respective intermediate station / stacking device, or to the object property of the predecessor object last routed to the respective intermediate station / stacking device.

[0138] For example, if a stack in a stacking device began with a laterally offset flat object, the sorting criterion can be set to stack subsequent flat objects on this stack that exhibit a similar lateral offset along the transport path. Or, if, for example, the cathode of the last monocell placed is off-center / twisted, it is advantageous to place a new monocell with an anode that is off-center / twisted in the same direction or orientation.

[0139] Alternatively, the target object property can be contrary to the object properties of several previous objects already routed to the respective intermediate station / stacking device, or contrary to the object properties of the flat objects located / stacked there. For example, if the electrical quality of the flat objects stacked in a stacking device is low, the sorting criterion can be specified so that, to compensate, flat objects with a higher electrical quality are selectively sorted to this intermediate station / stack.

[0140] It is also possible for a specific target property of a stack to be predefined before the start of sorting or stack formation, and for the target object property of a selected stacking device to be adjusted during the stacking of the flat objects in this stacking device in order to achieve this target property of the stack. For example, the target property of a stack can be specified as that the total height of a stack does not exceed a maximum height. If, for example, thick monocells tend to be stacked on top of each other at the start of the stack, thinner monocells are deliberately stacked on top of this stack as the sorting process progresses in order not to exceed the maximum height of the stack. Any thicker monocells to be sorted are directed to another stacking device in the meantime.

[0141] D) In ​​a fourth sorting variant, at least one predefined sorting criterion / sorting class as well as at least one dynamic sorting criterion or sorting classes are used.

[0142] This is explained using the example from Fig. 3, in which the position tolerance of an electrode 14 on the carrier 11 is used as the object property and sorted based on this according to a best-fit method.

[0143] Flat objects 15 are sorted, the position of which has been determined by a sensor 9 of the sorting device 10. Four stacking devices are available for sorting, into which the electrodes are guided by means of transport switches to form four stacks AD of flat objects 15. The sorting function of the transport switches is indicated by the arrows in Fig. 3.

[0144] Predefined sorting criterion:

[0145] Based on the initial specifications (defined before the first planar object was placed) and the planar objects placed on a stack so far, the four stacks AD each have their own overall tolerance field 12 for the position of the electrode 14 on the carrier 11, which defines whether a newly arriving planar object can be placed on this stack.

[0146] Dynamic sorting criterion: Based on the properties of the topmost flat object 15 of each stack (A, B, C, D), each stack has a dynamic tolerance field 13 (which differs from the overall tolerance field 12). This field also defines whether a newly arriving flat object may be placed on this individual stack. In this example, the dynamic tolerance field 13 depends on the position of the electrode 14 on the carrier 11 of the topmost flat object 15 of the stack and changes accordingly during stacking. The dynamic tolerance fields 13 can also have different sizes to sort according to different qualities.

[0147] For the placement of further flat objects 15, the following conditions are used:

[0148] - MUST: Both tolerance zones 12 and 13 must be maintained. If the electrode 14 of a flat object 15 to be deposited lies outside one of the tolerance zones 12 and 13 of all four stacks AD, the flat object in question will not be deposited there, but will be sorted out, for example.

[0149] - CAN Condition: if there are several storage options, the best-fit method is used to decide on which stack AD the flat object 15 is placed in order to place it on the best-fitting stack.

[0150] Stack A collects all flat objects 15 with electrodes 14 shifted to the left, stack D collects all flat objects 15 with electrodes 14 shifted to the right, and stacks B and C collect all flat objects 15 with centrally located electrodes 14. Stacks B and C differ in that in stack B, the dynamic tolerance fields 13 lie in all directions within the overall tolerance field 12 for this stack. Thus, for stack B, only the dynamic tolerance field 13, i.e., the positional tolerance relative to the adjacent flat object 15, needs to be considered. For stack C, however, the overall tolerance field 12 limits the range of the tolerance field of adjacent flat objects 15 and must therefore be considered additionally. Fig. 4 schematically illustrates the sorting of flat objects into multiple stacks based on various possible sorting criteria. The material flow from a large number of flat objects branches into multiple stacks 1, 2, ...n. For an object to be stacked, object-specific data is provided, e.g., by the sensor device 9 or the pre-processing device 40. This data is then checked against various sorting criteria, e.g., correlated with the stacking requirements of the individual stacks 1, 2,...n. A test result is generated that indicates whether or not the object-specific data of the respective flat object fulfills the respective sorting criterion or stacking requirement, and the stack is selected based on the test result. The flat objects sorted according to Fig. 4 can, for example, be monocells from which monocell stacks are formed, or they can be electrodes that are stacked in magazines.

[0151] Batch requirements can include predefined batch requirements and / or dynamic batch requirements defined by the objects already in the respective stack. Dynamic batch requirements can be defined, for example, by the object-specific data of the first object placed at the bottom of the stack, by the object-specific data of the topmost object in the stack, or by a batch property resulting from the object-specific data of all objects in the stack.

[0152] For example, several object properties are checked for a given flat object based on several stacking requirements (sorting criteria). Sorting criteria or stacking requirements include, for example, that positional deviations between stacked objects are below a certain threshold and that the fluctuation of an electrical or geometric object property across the entire stack must be within a certain tolerance. Depending on which sorting criteria / stacking requirements are met for the flat object and which are not, an overall test result is generated for several object properties of the given flat object.

[0153] If the test result shows that the respective object meets the respective stacking requirements, it may be stacked on the respective stack. If the test result shows that the respective flat object could be assigned to more than one stacking device, the sorting decision can be made using the best-fit method, i.e. the object is stacked on the stack to which it best fits or is most similar based on its object-specific data. The sorting decision can also be made such that the flat objects are distributed as evenly as possible across these stacks or such that one of these stacks is completed as quickly as possible. If the respective object does not meet the stacking requirements of any of the stacks, it is sorted out (reject).

[0154] Fig. 5 shows an example overview of possible process steps in monocell production, from the starting materials (electrodes and separator foils) to the sorting of the monocells. The right part of Fig. 5 shows how object-related data is generated during the individual process steps of monocell production. For each individual monocell, a data set Q is created, which is then used as the basis for the sorting decision on which the stack X' (A z , B', ... or N') the respective object should be stacked. Ql(X) is the data set of your previous object Ql on a stack X, i.e., the properties of the object on top of the substack X. The sorting decision can be made as described in Fig. 4.

[0155] Analogous to the sorting of monocells shown in Fig. 5, the procedure for producing battery element stacks can also be z-folded or for stacking individual electrodes. Before deciding on which

[0156] Stack is stacked, then other process steps would be required accordingly.

Claims

Patent claims 1. A method for sorting flat objects (i) used for the production of galvanic cells, in particular electrochemical energy storage devices or converters, in which a plurality of the flat objects are transported individually one after the other along a transport path (5) to at least two intermediate stations (4a-c) with the aid of at least one transport device, wherein at least one branching device (6, 6a-c) is arranged along the transport path, at which branching device the transport path branches such that the flat objects can be transported selectively to a first of the intermediate stations or to at least one further of the intermediate stations, wherein, for sorting the flat objects, the following steps are carried out for each of the flat objects: - Providing at least one object property of the respective planar object (i) and assigning the object property to the respective planar object and - selecting one of the intermediate stations (4a-c) for the respective planar object depending on the object property(ies) of the respective planar object in order to assign the respective planar object to the selected intermediate station, and - Transporting the respective flat object (i) along the transport path (5) to the intermediate station selected for the respective flat object, wherein the respective flat object is guided by the branching device (6, 6a-c) to the intermediate station (4a-c) selected for the respective flat object.

2. Method according to claim 1, wherein the intermediate stations (4a-c) are components of a production line for galvanic cells, in particular electrochemical energy storage devices or converters, wherein the Intermediate stations are each designed, in particular, to collect several flat objects for further processing into galvanic cells, in particular electrochemical energy storage devices or converters.

3. Method according to one of the preceding claims, wherein the at least one object property of the respective planar object (i) relates to one or more of the following object properties: - geometric property(ies) of the flat object, e.g. geometric dimension(s) such as length, width, thickness of the flat object; angular deviations; parallelism of the edges; straightness of the cutting edges; area of ​​the flat object; - Position of the planar object on the transport path, e.g. displacement or rotation, or a relative position of two sub-elements of the planar object, - Quality information about the flat object, - Material property(ies) of the flat object, e.g. homogeneity or porosity or the number, type or properties of defects or faults of the flat object, - electrical property(ies) of the flat object.

4. Method according to one of the preceding claims, wherein the / at least one of the provided object properties relates to a previously known material property of the respective planar object (i) and / or an object property of the respective planar object (i) determined in a preliminary process of the sorting method.

5. Method according to one of the preceding claims, wherein the flat objects (i) are transported along the transport path (5) one after the other past a sensor device (9) which is arranged in front of the at least one branching device (6, 6a-c) is arranged, wherein the sensor device detects at least one measurement signal of the respective flat object and determines the object property / at least one of the object properties of the respective flat object on the basis of the measurement signal detected for the respective flat object.

6. Method according to one of the preceding claims, wherein such flat objects which do not meet certain minimum requirements are sorted out in advance by a pre-sorting device (16, 17; 61, 20) arranged upstream of the branching device and only the flat objects remaining on the transport path (5) after the pre-sorting are transported further to the at least one branching device (6, 6a-c) and / or are used for the production of galvanic cells, in particular electrochemical energy storage devices or converters.

7. Method according to one of the preceding claims, wherein at least two of the intermediate stations (4a-b) each have a stacking device (41) for the flat objects, which is designed to deposit the flat objects transported to it along the respective transport path onto a stack holder (42) of the respective stacking device in order to stack them there on a stack which has a plurality of the flat objects.

8. Method according to one of the preceding claims, wherein when selecting the intermediate station (4a-c), in particular stacking device (41), the at least one object property determined for the respective flat object (i) is checked on the basis of at least one sorting criterion and a test result is generated which indicates whether the object property(ies) of the respective flat object fulfill(s) the respective sorting criterion or not, and that the intermediate station for the respective flat object is selected depending on the test result, wherein for the respective flat object, preferably several object properties are checked using several sorting criteria in order to determine an overall test result for several object properties of the respective flat object, which overall test result is determined depending on which sorting criteria are met for the flat object and which are not.

9. Method according to one of the preceding claims, wherein when selecting the intermediate station (4a-c), in particular stacking device (41), the at least one object property provided for the respective flat object is checked on the basis of at least one sorting criterion and the flat objects are assigned to different sorting classes depending on whether the respective flat object fulfills the at least one sorting criterion or not, wherein the intermediate stations, in particular stacking devices, are assigned to the different sorting classes or are assigned to the different sorting classes during the sorting.

10. The method according to claim 9, wherein the sorting classes comprise at least two different acceptance sorting classes (A1, A2), to which at least one of the intermediate stations, in particular at least one of the stacking devices, is assigned for those flat objects which are transported to the intermediate stations, in particular stacking devices, in order to make them available for further processing into galvanic cells, wherein the sorting classes preferably additionally comprise at least one reject sorting class for those flat objects which are sorted out in order not to use them for the production of galvanic cells.

11. Method according to one of the preceding claims, wherein the intermediate stations (4a-c), in particular stacking devices (41), for at least one object property is assigned at least one target value and / or at least one value range or is assigned during the sorting process, and in order to decide which of the intermediate stations (4a-c), in particular stacking devices, is selected for the respective flat object, the corresponding object property of the respective flat object (i) is compared with the target values ​​and / or with the value ranges of several of the intermediate stations (4a-c), in particular stacking devices, and in that the respective flat object is assigned to one of the intermediate stations, in particular stacking devices, depending on the comparison results of this comparison and is transported there, and in particular is stacked there.

12. Method according to claim 11, wherein for the respective flat object (i) that intermediate station (4a-c), in particular stacking device (41), is selected whose target value(s) is / are closest to the value(s) of the corresponding object property of the flat object and / or in whose value range(s) the value of the corresponding object property of the flat object is contained, and that the respective flat object is assigned to the selected intermediate stations, in particular stacking device, and is transported there, in particular is stacked there.

13. Method according to one of the preceding claims, wherein the intermediate stations (4a-c) each have a stacking device (41) for stacking the flat objects and wherein in these stacking devices - a stack target value and / or stack target range is defined for a stack property of a stack of flat objects to be formed in the respective stacking device, and- for the flat objects already stacked in the respective stacking device, an actual value is determined for the relevant stacking property during sorting, and based on the stack target value / stack target range predetermined for the stacking property and the actual value determined for the stacking property of the respective stacking device, it is examined whether the stack formed in the respective stacking device with the actual value is likely to reach the stack target value / stack target range or not after further flat objects have been placed on this stack, and that in the event that the stack formed in the respective stacking device with the actual value is likely not to reach the stack target value / stack target range, then those flat objects are specifically or preferentially selected for stacking in the respective stacking device whose object property changes the actual value in such a way thatthat the actual value approaches the batch target value / batch target range., 14. Method according to one of the preceding claims, wherein the intermediate stations (4a-c) each have a stacking device (41) for stacking the flat objects and wherein in these stacking devices for one or more flat objects the decision as to which of the stacking devices is selected for the respective flat object is made depending on the object properties of one or more uppermost flat objects which are currently deposited on top of the stacks located in the stacking devices, wherein at least one of the stacking devices is assigned in particular a dynamic target value / dynamic value range of at least one object property which is selected depending on the value of the corresponding object property of the uppermost flat object of the stack deposited in the stacking device.

15. Method according to one of the preceding claims, wherein at least one sorting class, to which at least some of the planar objects are assigned, is determined dynamically, wherein in the dynamically determined sorting class at least one sorting criterion of the sorting class is not yet determined before the start of the sorting of the planar objects, but is only determined after the start of the sorting of these planar objects, preferably by at least one object property of at least a first planar object which was / was first transported to the respective intermediate station, in particular stacking device, in particular after the respective stacking device was made ready to receive a new stack.

16. Method according to one of the preceding claims, wherein the intermediate stations (4a-c) each have a stacking device (41) for stacking the flat objects and wherein at least one of the stacking devices is a dynamically selected stacking device, in which, after the respective stacking device has been made ready to receive a new stack, one or more first flat objects are assigned to the dynamically selected stack receptacle thus provided in order to stack it / them there, and wherein, after the assignment of the first flat object(s) to the dynamic stacking device, for one or more subsequent flat objects, the decision as to which of the stacking devices is selected for the respective subsequent flat object is made depending on the object properties of the first flat object(s) which are already stacked in the stacking device.

17. The method according to claim 16, wherein the dynamically selected stacking device to which the first planar object(s) was / are assigned, at least one dynamic target value / value range at least is assigned to an object property which is selected depending on the value of the corresponding object property of the first planar object(s), and wherein one or more of the subsequent planar objects, the value of the object property of which at least approximately corresponds to the dynamic target value or the value of the object property of which lies in the dynamic value range, is / are also assigned to this dynamically selected stacking device and is / are stacked on the first planar object(s).

18. Device (5) for sorting flat objects used for the production of galvanic cells, in particular electrochemical energy storage devices or converters, comprising: - at least two intermediate stations (4a-c), - one or more transport devices (2, 2a-b) which are designed to transport a plurality of the flat objects one after the other along a transport path (5) to the intermediate stations, - at least one branching device (6) arranged on the transport path (5), at which the transport path (5) branches off in such a way that the flat objects can be transported along the transport path selectively to a first of the intermediate stations or to at least one further of the intermediate stations, - a selection device (8, 8a) which has at least one object property of the respective planar object for the planar objects and which is designed to select one of the intermediate stations for the respective planar object depending on the object property(ies) of the respective planar object in order to assign the respective planar object to the selected intermediate station, wherein the selection device (8) or a device connected to the selection device connected control device (8b) for sorting the flat objects is designed to control the at least one branching device such that the respective flat object is guided by the branching device (6, 6a-c) to the intermediate station selected for the respective flat object in order to transport it along the transport path to the selected intermediate station.

19. Device according to claim 18, wherein the device has a sensor device (9, 19) which is arranged along the transport path (5) such that the flat objects are transported past the sensor device (9, 19), wherein the sensor device is arranged in front of the at least one branching device (6, 6a-c) and is designed to detect at least one measurement signal of the respective flat object and to determine the object property / at least one of the object properties of the respective flat object on the basis of the measurement signal detected for the respective flat object and to make it available to the selection device (8, 8a).

20. Device according to one of claims 18 to 19, wherein at least two of the intermediate stations (4a-c) each have a stacking device (41) for the flat objects, which is designed to deposit the flat objects transported to it along the respective transport path onto a stacking receptacle (42) of the respective stacking device in order to stack them there on a stack which has a plurality of the flat objects.

21. Device according to one of claims 18 to 20, wherein the selection device (8, 8a) of the device is designed to select the intermediate station (4a-c), in particular stacking device, the at least one object property determined for the respective flat object to check based on at least one sorting criterion and to assign the flat objects to different sorting classes depending on whether the respective flat object fulfills at least one sorting criterion or not.

22. Device according to one of claims 18 to 21, wherein the selection device (8, 8a) is designed to assign at least one target value and / or at least one value range to the intermediate stations (4a-c), in particular stacking devices, for at least one object property and - to decide which of the intermediate stations, in particular stacking devices, is selected for the respective flat object, to compare the corresponding object property of the respective flat object with the target values ​​and / or with the value ranges of several of the intermediate stations, in particular stacking devices, and to assign the respective flat object to one of the intermediate stations, in particular stacking devices, depending on the results of this comparison and to ensure that it is transported there and, in particular, stacked there.

23. Device according to one of claims 18 to 22, wherein the intermediate stations each have a stacking device (41) for stacking the flat objects and wherein the selection device (8, 8a) of the device is designed to - to specify a stack target value and / or a stack target range for a stack property of a stack of flat objects to be formed in the respective stacking device, - and to determine an actual value for the relevant stacking property for the flat objects already stacked in the respective stacking device during sorting, and to examine, on the basis of the stack target value / stack target range predetermined for the stacking property and the actual value of the relevant stacking device determined for the stacking property, whether the stack formed in the relevant stacking device with the actual value is likely to reach the stack target value / stack target range or not after further flat objects have been placed on this stack, wherein the selection device (8, 8a) is designed to, in the event that the stack formed in the relevant stacking device with the actual value is likely not to reach the stack target value / stack target range, then specifically or preferentially select those flat objects for stacking in the relevant stacking device whose object property changes the actual value in such a way,that the actual value approaches the batch target value / batch target range., 24. Device according to one of claims 18 to 23, wherein the intermediate stations (4a-c) each have a stacking device (41) for stacking the flat objects and wherein the selection device (8, 8a) of the device is designed to make the decision, in these stacking devices for one or more flat objects, as to which of the stacking devices is selected for the respective flat object, depending on the object properties of one or more uppermost flat objects which are currently deposited on top of the stacks located in the stacking devices, wherein the selection device is designed to assign to at least one of the stacking devices a dynamic target value / dynamic value range of at least one object property, which is dependent on the value of the corresponding Object property of the uppermost planar object of the stack deposited in the stacking device is selected, and wherein the selection device is designed to assign the respective planar object to the respective stacking device and to stack it on the uppermost planar object only if its value of the object property at least approximately corresponds to the dynamic target value or its value of the object property lies in the dynamic value range, and otherwise, if the value of the object properties does not correspond to the dynamic target value / value range, to assign the subsequent planar object to another stacking device or to sort it out.

25. Device according to one of claims 18 to 24, wherein the selection device (8, 8a) of the device is designed to dynamically determine at least one sorting class to which at least some of the flat objects are assigned, wherein the selection device of the device is designed to determine at least one sorting criterion of the sorting class in the dynamically determined sorting class not before the start of the sorting of the flat objects, but only after the start of the sorting of these flat objects, preferably on the basis of at least one object property of at least a first flat object which was / was first transported to the respective intermediate station, in particular stacking device, in particular after the respective stacking device has been made ready to receive a new stack.

26. Device according to one of claims 18 to 25, wherein the intermediate stations (4a-c) each have a stacking device (41) for stacking the flat objects and wherein the selection device of the device is designed to dynamically select at least one of the stacking devices, wherein and the selection device (8, 8a) of the device is designed to assign one or more first planar objects of the dynamically selected stack receptacle thus provided to the dynamically selected stacking device, after said stacking device has been made ready to receive a new stack, in order to stack it / them there, and wherein the selection device is designed, after the first planar object(s) have been assigned to the dynamic stacking device, to make the decision as to which of the stacking devices is selected for the respective subsequent planar object, depending on the object properties of the first planar object(s) which are already stacked in the stacking device.

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