Battery arrangement, battery system including the battery arrangement, and method for checking the manufacturing status of the battery arrangement

Abstract

A battery arrangement 1 is proposed, comprising at least one battery 2, wherein the battery 2 has at least one pole 3a for electrical contacting the battery 2, the pole 3a forming a first contact partner, with a contact element 4 for electrical contacting the pole 3a, the contact element 4 forming a second contact partner, wherein in a joining state as a first manufacturing state of the battery arrangement 1 the contact element 4 rests on the pole 3a in at least one joining area 5 ready for joining / suitable for joining and / or wherein in a contacting state of the battery arrangement 1 as a second manufacturing state the contact element 4 is materially bonded to the pole 3a in one and / or the at least one joining area 5, with a sensor section 6 for checking at least one of the manufacturing states of the battery arrangement 1, wherein the sensor section 6 is arranged between the contact element 4 and the battery 2.wherein the sensor section 6 is printed at least partially or completely on one of the contacting partners.

Description

[0001] The invention relates to a battery arrangement having the features of claim 1. The invention also relates to a battery system having a plurality of such battery arrangements and to a method for checking the manufacturing state of the battery arrangement.

[0002] Storage units for vehicles, electrical devices, etc. often have battery packs with numerous individual batteries. These individual batteries must be electrically connected to each other within the battery packs and to a load structure. In principle, electrical contacting is a simple manufacturing process. However, in such battery packs, numerous individual batteries must be contacted, so that, from a purely statistical perspective, it cannot be ruled out that one or more contacts will not be made completely. Depending on the contact structure, even a single faulty contact can lead to a failure or reduced performance of the battery pack.It is therefore imperative to either implement the contacting 100% error-free or at least to be able to check the contacting afterwards in order to be able to subsequently rectify any faulty contacts or to be able to identify in advance any unstable contacting that could fail during later operation.

[0003] The document DE 10 2020 129 385 A1 discloses a method for determining a quality measure of a material connection between two electrically conductive joining partners arranged one above the other, e.g. in a battery cell, in which a current profile is impressed into the material connection and a voltage drop across the connection caused by the impressed current is determined via measuring contacts, and in which the quality measure of the material connection is determined from a predetermined relationship between the current profile and the voltage drop.

[0004] The document DE 10 2021 123 246 A1 discloses a battery arrangement comprising a plurality of energy storage cells, wherein the energy storage cells have connection poles to which cell connectors are fastened, in particular welded, for interconnecting the energy storage cells, and wherein the energy storage cells are connected to a contacting system which is formed by a printed circuit board having a cover layer on both sides, wherein the printed circuit board is arranged between the connection poles and the cell connectors in such a way that the fastening points, in particular the weld points, via which the cell connectors are indirectly connected to the connection poles via the printed circuit board, are protected from external influences by the cover layers.

[0005] It is an object of the present invention to propose a battery arrangement with an improved possibility for checking the contacting.

[0006] This object is achieved by a battery assembly having the features of claim 1, by a battery system having the features of claim 15, and by a method for testing the manufacturing state of the battery assembly having the features of claim 16. Preferred or advantageous embodiments of the invention emerge from the subclaims, the following description, and the accompanying figures.

[0007] The invention thus relates to a battery arrangement which is particularly suitable and / or designed for a battery system.

[0008] The battery arrangement comprises at least one battery. The battery is designed, in particular, as a single cell. However, it can also be provided that the battery is implemented as a multiple cell. The battery can be designed, in particular, as a rechargeable battery, specifically as an accumulator. In particular, the battery stores energy on an electrochemical basis. Alternatively, the battery is designed as a capacitor bank.

[0009] The battery has at least one terminal for electrically contacting the battery. In particular, the terminal is designed as a positive terminal or a negative terminal. The battery preferably comprises at least one positive terminal and at least one negative terminal. The terminal forms a first contact partner in the battery arrangement.

[0010] The battery arrangement has a contact element for electrically contacting the pole. The contact element can be designed, for example, as a metal strip, a contact structure, etc. In particular, the contact element is designed to be rigid, at least in the contact area. Specifically, the joint of the contact element is designed to be rigid. The transition between the joint and a main structure of the contact element for discharging the current collected from possibly different batteries can be designed to be flexible, so that tolerance compensation can take place, to compensate for thermal movements, geometric tolerances, compensating movements during assembly, etc., and so that no stresses or reduced stresses arise in the joint and the connection is not damaged by stresses in the material.However, locally (especially measured in a few millimeters), the contact element is preferably designed to be rigid, especially since the aspect ratios in the contacting area ensure this. The contact element connects the terminal, for example, to a load structure. The contact element forms a second contact partner in the battery assembly.

[0011] It is provided that the battery arrangement in a joining state as a first manufacturing state of the battery arrangement the contact element rests on the pole in at least one joining region ready for joining and / or in a manner suitable for joining.

[0012] The joining area is defined in the joined state as the area in which the contact element rests on the pole, ready for joining and / or correctly. Alternatively or additionally, the contacting state is defined as the area in which the contact element is firmly and / or permanently connected to the pole.

[0013] In the joined state, the pole and the contact element are not yet in a materially bonded and / or permanent contact, but are arranged in a manner suitable for joining and / or ready for joining, but in particular unconnected or only "tacked." The contact element can rest on the pole in a contacting manner. Alternatively, a joining gap is present between the contact element and the pole, but this gap is dimensioned so small that the subsequent joining process can be carried out successfully. Both with mechanical contact and when resting with a joining gap, the battery assembly is in the joined state and is thus arranged ready for joining and / or correctly for joining.

[0014] Alternatively or additionally, the battery arrangement is in a contacting state of the battery arrangement, wherein the contacting state forms a second manufacturing state. In the contacting state, the contact element is integrally connected to the pole in one and / or in the at least one joining region. The integral connection is effected in particular via a metal melting process, in particular via a metal welding process, in particular laser beam welding, ultrasonic welding or resistance welding. In particular, the joining takes place without additional material. Alternatively, a metal soldering process can also be used, wherein, for example, the solder is provided to the contacting partners via a solder depot.

[0015] The battery assembly has a sensor section, wherein the sensor section is suitable and / or configured to check at least one of the manufacturing states of the battery assembly. It can thus be provided that the sensor section checks the joining state or the contacting state, or alternatively, the joining state and the contacting state. In particular, the check is carried out with regard to a positioning that is suitable for joining and / or ready for joining in the joining state and / or with regard to sufficient contact between the contact element and the terminal in the contacting state.

[0016] Within the scope of the invention, it is proposed that the sensor section be arranged between the contact element and the battery, in particular in the region of the terminal. Preferably, the sensor section is clamped between the contact element and the battery. For example, if the battery arrangement is viewed from above, the sensor section, the contact element, and the battery, in particular the terminal of the battery, are positioned congruently. In particular, the sensor section is arranged in the region of the terminal.

[0017] One idea of ​​the invention is to place the sensor section as close as possible to the actual test point, namely the joining area. Because the sensor section is arranged between the contact element and the battery, particularly in the area of ​​the terminal and / or the joining area, the sensor section can directly detect the joining area. This proposes a battery assembly that offers a novel way of checking the positioning and / or contacting of the contact element at the terminal.

[0018] In a preferred embodiment of the invention, the sensor section is arranged circumferentially and / or overlapping the at least one joining area. Alternatively or additionally, the sensor section is positioned adjacent, in particular directly adjacent. Due to the immediate proximity to the joining area, which – as already described – is achieved by positioning the sensor section, the joining area can be inspected particularly easily with regard to its manufacturing status.

[0019] In particular, the sensor section can be applied to the contact element and / or to the battery. It is also possible for the sensor section to be applied partially to the contact element and partially to the battery by coating.

[0020] In a preferred embodiment of the invention, the sensor section is applied at least partially or completely to one or both of the contact partners by coating. The coating for creating the sensor section is implemented in particular by applying a firmly adhering layer of amorphous material, in particular a functional ink and / or a functional paint, to the surface of the contact partner or a preceding layer. Because the sensor section is applied by coating, it takes up virtually no installation space, so that when the sensor section is arranged between the battery and the contact element, no interfering contour is created that would negatively impact the joining process.

[0021] However, this positioning could potentially result in the contact element being mechanically separated and / or spaced from the terminal. Because the sensor section is applied to at least one of the contact partners, at least partially or completely by coating, it is designed to be particularly thin, so that it does not form an interfering contour between the contact element and the terminal. This allows the contact between the contact element and the terminal to be made without interference from the sensor section, while still allowing the sensor section to monitor the joining area in close proximity.

[0022] Particularly preferably, the sensor section is printed. Printing is carried out, in particular, by applying the functional ink and / or the functional color to the respective contact partner. For example, the printing process is carried out using an inkjet process.

[0023] It is preferred that the sensor section has a thickness of less than 25 µm, in particular less than 10 µm, and especially less than 1 µm. This small thickness ensures that the sensor section does not act as an interfering contour, even with a "zero gap," for example, for laser welding. Rather, the small distance between the pole and the contact element caused by the sensor section can be bridged in a process-tolerant manner during joining.

[0024] In a preferred embodiment of the invention, the sensor section has a test structure applied by coating, wherein the test structure is electrically conductive at least in sections. In particular, the test structure is realized in metal. The test structure can have any desired selection of conductor tracks, resistors, capacitors, etc. Such a test structure allows the sensor section to be easily adapted to the required test.

[0025] Optionally, the sensor section can have a base layer and / or a cover layer, wherein the test structure is arranged on the base layer or beneath the cover layer, such that the sensor section is designed as a layered device. The base layer can have fewer details than the test structure of the sensor section, such that a less precise application method can be selected to produce the base layer. For example, it is possible for the base layer to be adhesively bonded. However, since such adhesive bonding could increase the thickness of the sensor section and thus lead to a possible interference contour between the pole and the contact element, it is preferred that the base layer is also applied by coating, in particular printing. The base layer is designed in particular as an insulation layer and / or as an adhesion promoter layer. The test structure is preferably arranged on the base layer.

[0026] The battery layer device can comprise the cover layer, wherein the cover layer is applied to the test structure. The cover layer can have fewer details compared to the test structure, so that a less precise application method can be selected to create the cover layer. For example, it is possible for the cover layer to be glued on. Due to potential disadvantages associated with the thickness, it is preferred that the cover layer be applied by coating, in particular printing.

[0027] The base layer and / or the cover layer are preferably limited to the functionally important areas, e.g., for isolating the test structure. In particular, the base layer and / or the cover layer can be left out at the joint, provided they are not required for isolating the test structure, in order to minimize the material ingress into the joint through the base layer and / or the cover layer.

[0028] It is particularly preferred that the sensor section, in particular the test structure, has at least one measuring region. The measuring region is arranged congruently and / or overlapping and / or circumferentially and / or adjacent to the joining region. In the measuring region, the manufacturing state of the battery assembly is checked in the joining region, i.e., locally. It can also be provided that the sensor section has several such measuring regions, which check several joining regions of the battery assembly. However, it is preferably provided that the majority of the joining regions are assigned to a pair of pole contact elements.

[0029] In principle, the sensor section, particularly the measuring range, can be configured for temperature measurement to measure a process temperature, frequency measurement to measure frequencies, e.g., during resistance welding, or for measuring other process variables, etc. By recording process variables, the respective production status can be checked. In particular, the process variables are forwarded to an evaluation device or queried by it and processed there in relation to the production status of the battery assembly.

[0030] In a preferred embodiment of the invention, the measuring region comprises a first electrode structure and a second electrode structure. The measuring region can be limited to the two electrode structures; alternatively, additional electrode structures can also be present. The first electrode structure and the second electrode structure are electrically separated from one another in an initial state of the sensor section. The joining region is arranged between the electrode structures.

[0031] It is preferred that the measuring area for an electrical continuity measurement for checking the manufacturing state of the battery arrangement is formed in the wing area.

[0032] In a preferred implementation, the measuring area is designed for an electrical continuity measurement to check the joining state of the battery arrangement in the joining area. In this implementation, an electrical continuity is generated in the measuring area by one of the contacting partners as a contacting partner applied, in particular by the contacting partner without a sensor section, and / or by the unjoined joining area, which electrical continuity can be determined and / or tapped via the sensor section. In particular, the applied contacting partner and / or the unjoined joining area connects the electrode structures. If, for example,If an electrical continuity in the measuring area is determined by a possible evaluation device in the joining state, it is assumed that the contacting partner rests on the sensor section, in particular on the measuring area, in such a way that an electrical continuity is formed in the measuring area via the contacting partner placed on it and the contacting partner rests in a manner suitable for joining and / or ready for joining.

[0033] Alternatively or additionally, in the contacting state, it is concluded, in particular by the evaluation device, that the joined joining area forms the electrical continuity in the measuring area, so that in the event of an electrical continuity, it can be concluded that the joining area is correctly joined.

[0034] The evaluation device is an optional component of the battery assembly. The evaluation device can be designed as an analog and / or digital data processing device.

[0035] In an alternative or a further development of the invention, the measuring region for an electrical resistance measurement for checking the manufacturing status of the battery arrangement is formed in the joining region. The electrode structures form a plurality of individual contact pairs, wherein the individual contact pairs can be designed as 1:1 contact pairs, in particular as individual contact bridges. It is possible for one electrode structure to have a collecting electrode for all or a subset of the individual electrode sections of the other electrode structure, and for only the other electrode structure to have individual electrode sections. In this case, the individual electrode sections form the individual contact pairs. However, it is also possible for each electrode structure to have one or more collecting electrode sections and individual electrode sections in order to form the individual contact pairs between the electrode structures.The individual contact pairs are conductively connected to one another depending on the manufacturing state: If the joining state and / or the contacting state is very good, all individual contact pairs are connected. If the manufacturing state is borderline, only a few of the individual contact pairs are connected. If the manufacturing state is poor, no individual contact pairs are connected to one another. The individual contact pairs each have at least or exactly one individual resistance. In the fully connected manufacturing state, the individual resistances of the individual contact pairs are arranged in parallel to one another, so that this parallel connection results in a total measuring range resistance depending on the contacted individual contact pairs. Based on the total measuring range resistance, a connection length in the joining area can be estimated in relation to the joining state and / or the contacting state.In particular, the assessment is carried out by the evaluation device.

[0036] Optionally, each of the individual contact pairs can have two individual resistors, with one of the individual resistors being assigned to each electrode structure. This refinement ensures that the individual connection lengths of both electrode structures are included in the estimation, allowing for a more accurate estimation of the connection length.

[0037] In a preferred development of the invention, the individual contact pairs are encoded via the respective individual resistance or resistances. For example, all individual resistances of one and / or the other electrode structure are designed differently, wherein the values ​​of the individual resistances are selected such that it is possible to estimate from the total measuring range resistance which individual contact pairs are electrically contacted and which individual contact pairs are open. In the simplest embodiment, the measuring range has two individual contact pairs which have different individual resistances. If both individual contact pairs are closed, then there is a total measuring range resistance which is formed from the two individual resistances. If only one individual contact pair is closed, the respective individual resistance of the individual contact pair results.This allows the different states of the measuring range to be distinguished: the joining state and / or the contacting state. In particular, a bonding distribution can be estimated based on the total measuring range resistance. The estimation is performed primarily by the evaluation device. If each of the electrode structures has corresponding coded individual resistances, the individual bonding distributions of both electrode structures are included in the estimation, allowing for a more accurate estimation of the bonding distribution.

[0038] In one possible structural embodiment of the invention, the sensor section has at least one contact area for contacting the sensor section, in particular the measuring area, with an evaluation device, wherein the contact area is printed on one of the contact partners. It is even possible for the contact area not to lie in the same plane as the sensor section, but rather to be arranged on a surface facing away from or parallel to it during 3D printing in order to enable easy access of the evaluation device to the sensor section during production of the battery arrangement. For example, a tap for the evaluation device can be introduced into a hold-down device of a tool for the joining process between the contact element and the pole, which tap automatically makes contact with the sensor section when the tool is closed.

[0039] The measuring area is preferably arranged in a measuring path between two contact areas, so that the continuity measurement and / or the resistance measurement can be carried out via the contact areas, e.g. by the evaluation device.

[0040] It is particularly preferred for the sensor section to have at least or exactly two of the measuring ranges. The pole is often connected to the contact element via a plurality of joining regions, with some or each of the joining regions being assigned such a measuring range. The measuring ranges are interconnected in the sensor section in such a way that a total section resistance is formed, with the manufacturing state of the battery arrangement in the respective joining region with the different measuring ranges being estimable on the basis of the total section resistance. If, for example, the embodiment with the coded individual resistors is considered, one measuring range can be designed with individual resistors in a first order of magnitude, e.g., in the order of magnitude of 1 kOhm, and the other measuring range can be designed with individual resistors in a second order of magnitude, e.g., in the order of magnitude of 100 kOhm, i.e., in a different order of magnitude than the first order of magnitude.The magnitudes can differ by a factor of 10 or more, for example. The manufacturing state of the battery assembly can be estimated for the respective joining area and / or the respective measuring ranges based on the magnitude of the total section resistance.

[0041] In the event that the sensor section has exactly two measuring areas, these can be connected in series, in particular between the contact areas, and form a measuring path, wherein a continuity measurement only results in an electrical continuity and thus a ready-to-join and / or joining-appropriate arrangement of the contact element on the pole in the joining state and / or a material connection between contact element and pole in the contacting state if both measuring areas are electrically connected.

[0042] If the two measuring ranges are configured for electrical resistance measurement to check the manufacturing status of the battery assembly in the joining area, they can be connected either in series in one measuring path or—provided the individual resistances of the measuring ranges differ sufficiently—in parallel in two measuring paths to detect a ready-to-join and / or correctly assembled arrangement of the contact element on the terminal in the joining state and / or a material connection between the contact element and the terminal in the contacting state. In this configuration, the two measuring ranges form a resistance network.

[0043] In a preferred development of the invention, the measuring ranges are arranged in one or the resistor network and / or - as just explained - form one or the resistor network. A plurality of, e.g. two, three, four, five or more measuring paths can be provided in the resistor network. Different measuring paths are encoded in the resistor network by path resistors. Alternatively or additionally, the measuring ranges have individual resistors so that the total section resistance is formed from the components of the resistor network. In addition to coding the measuring ranges via the individual resistors, it is thus also possible to introduce one or more path resistors into the measuring paths so that the different measuring paths can be differentiated.For example, the measuring areas between two contact areas of the sensor section are arranged electrically in parallel, with each parallel path forming a measuring path that is encoded via a path resistance. Optionally, and for testing the joining condition, conductive pads are arranged on the contact partner to be pressed onto the sensor section, which are insulated from the conductive base material of the contact partner. For example, an imprint on the contact partner to be joined is necessary. This ensures that short circuits cannot occur between the measuring areas through or via the base material of the contact partner to be pressed. The pads preferably each have an insulating base layer and an electrically conductive cover layer. In particular, the pads or at least the electrically conductive cover layer are each limited to a measuring area or joining area.

[0044] Alternatively or additionally, a path resistance is arranged in each measuring path before and after each measuring area. The path resistances of the various measuring paths are designed differently so that the respective measuring path is uniquely coded via the combination of the path resistances and / or so that the joining state of the joining areas can be determined from the total resistance. In particular, the measuring path can have significantly higher resistance values ​​than the resistance of the joining area, e.g., at least 10 times, at least 100 times, or more. Alternatively or additionally, however, it can be smaller than the parasitic resistance without the joining partner applied or the joined connection.

[0045] Particularly preferably, each of the measuring paths has a measuring range and a path resistor arranged upstream and downstream, wherein the path resistors uniquely encode the measuring paths. In one possible embodiment, the measuring paths, in particular all measuring paths or a subset thereof, are arranged electrically parallel to one another.

[0046] If more than two measuring ranges are to be arranged in the resistor network, it is preferable that a maximum of two measuring ranges are arranged in each measuring path. This ensures that each of the measuring ranges is reliably detected without missing a measuring range due to a short-circuit connection via one of the contact partners.

[0047] Alternatively, in each connection between two measuring ranges in a measuring path, a resistor is formed which is formed by the individual resistors or by a path resistor and thereby encodes a measuring path section.

[0048] In the event that the contacting partner has a metallic surface or conductive surface, it is preferred that the sensor section has the insulating bottom layer via which the test structure is electrically insulated from the contacting partner on which the test structure is printed.

[0049] For use of the sensor section to check the joining state, it is preferred that the sensor section is designed to be contact-capable at least in sections in the initial state, particularly in the joining area and / or measuring area, so that the sensor section can make electrical contact with the contact partner placed thereon in the joined state in order to check the joining state. Simply put, the contact partner is placed on the other contact partner or on the contact partner with the sensor section, so that an electrical connection is closed, particularly in the measuring area. This is made possible by the fact that the sensor section, particularly the measuring area, is contact-capable in sections.

[0050] In contrast, when the sensor section is used to check the contact state, it is preferred that the sensor section be electrically insulated from the contact partner in the joined state and / or in the initial state, particularly in the joining region and / or measuring region, at least in sections. This prevents an electrical continuity or the like from being created in the joined state. However, it is provided that the sensor section is electrically connected in the contact state depending on the contact state in the measuring region in order to check the contact state.In particular, it is intended that the joining process, on the one hand, connects the contacting partners to one another in a material-to-material manner and, on the other hand, the material-to-material connection dissolves the electrical insulation and an electrical connection is created between the electrode structures in the measuring area so that the contact state can be checked.

[0051] Another subject matter of the invention relates to a battery system, wherein the battery system has a plurality of battery arrangements as described above or according to one of the preceding claims. The battery system can be designed, for example, as a battery system for an electric drive of a vehicle. However, it can also be designed as a stationary or mobile energy storage device. In principle, the battery system can have a few battery arrangements, e.g. more than 2, 3, 4 or 5. The battery can be designed as a straight cylinder, in particular a circular cylinder. In particular, the battery forms a round cell. Alternatively, the battery is rectangular or cuboid-shaped. In particular, the battery can be designed as a “blade,” which is designed as a narrow cuboid.The battery system preferably has at least 50, in particular at least 80, and especially at least 100 battery arrangements, particularly in the form of cylinders. If cells with a rectangular format are used instead of cylindrical cells, the number can be smaller, i.e., less than 50, but should be at least 6, 10, or 16. The battery system preferably has mostly or exclusively battery arrangements, so that a large portion or all of the batteries are controlled. Especially in the area of ​​power tools, the consumer sector, or the like, the battery system can have fewer than 10 battery arrangements, especially fewer than 5 battery arrangements. For example,at least or exactly three battery arrangements (in particular for 12V battery systems) or at least or exactly four battery arrangements (in particular for 24V battery systems), or at least or exactly eight battery arrangements (in particular for 48V battery systems) or battery systems with only two battery arrangements.

[0052] Another subject of the invention relates to a method for checking the manufacturing state of a battery assembly, as described above or according to one of the preceding claims. It is provided that the battery assembly is brought into one of the manufacturing states, and the manufacturing state of the battery assembly is checked via the sensor section.

[0053] Further features, advantages, and effects of the invention will become apparent from the following description of preferred embodiments of the invention. These show: Fig. 1 a schematic, three-dimensional representation of a battery arrangement as an embodiment of the invention; Fig. 2 a schematic longitudinal section through the battery arrangement of the Fig. 1; Fig. 3 ah different variants for a measuring range in a sensor section in the battery arrangement of the previous figures; Fig. 4 shows a first embodiment of a sensor section for the battery arrangement of the preceding figures. Fig. 5 a second embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 6 a third embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 7 a fourth embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 8 a fifth embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 9 a sixth embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 10 a seventh embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 11 an eighth embodiment of a sensor section for the battery arrangement of the preceding figures Fig. 12 a schematic, three-dimensional representation of a contact element of the battery arrangement.

[0054] Corresponding or identical parts are provided with the same reference numerals in the figures.

[0055] The Fig. 1 shows a highly schematic, three-dimensional view of a battery assembly 1 as an exemplary embodiment of the invention. The battery assembly 1 has a battery 2, which is designed as a single cell or as a multiple cell. In this exemplary embodiment, the battery 2 has two poles 3a, b, via which the battery 2 can be contacted with a load structure. Furthermore, the battery assembly 1 has a contact element 4, which is designed, for example, as a metal strip and which is intended to contact one of the two poles 3a, b in order to electrically connect the battery 2 to the load structure.

[0056] The contacting of the contact element 4 to the pole 3a mentioned by way of example is implemented via four joining regions 5, for example, although only one joining region 5 or more joining regions 5 can also be provided for contacting. Contacting is achieved via a material-to-material joining process, in particular without additional material. For example, the joining process is carried out via a metal melting process, such as welding or soldering. For example, the contact element 4 is fastened to the joining region 5 of the pole 3a in a material-to-material and electrically contacting manner using ultrasonic welding, resistance welding, or laser beam welding. The pole 3a forms a first contacting partner, the contact element 4 forms a second contacting partner.

[0057] Joining area 5 is formed by the contacting partners. Joining area 5 can be understood as the area to be joined, i.e., before the material connection between the contacting partners, and the joined area, after the material connection between the contacting partners.

[0058] A sensor section 6 is printed on one of the contact partners. It can be provided that the sensor section 6 is printed on the pole 3 a and / or on the contact element 4

[0059] The sensor section 6 has the function of checking the manufacturing state of the battery assembly 1. Depending on the design, the sensor section 6 can check the battery assembly 1 in a joining state as a manufacturing state to determine whether the contacting partners are ready to join and / or arranged correctly for joining, in order to subsequently perform a faultless joining process.

[0060] Alternatively or additionally, the sensor section 6 can check a contacting state of the battery arrangement 1 as a manufacturing state, whether the contact element 4 is materially and thus electrically connected to the pole 3 a in one of the joining regions 5.

[0061] The Fig. 2 shows a schematic sectional view of the battery arrangement 1, wherein the battery 2 with the pole 3 a, b and the contact element 4 are shown. From the illustration it can be seen that the sensor section 6 is arranged between the contacting partners, i.e. the pole 3 a and the contact element 4. When contacting the contact element 4 with the pole 3 a, however, a joining gap between the contact element 4 and the pole 3 or generally the contacting partners may only be very small in order to enable functionally correct contact. The sensor section 6, which is arranged in the joining gap between the contacting partners, has a small thickness, wherein the small thickness is made possible by printing the sensor section 6. The thickness of the sensor section 6 is in particular less than 25 µm, in particular less than 10 µm and especially less than 1 µm in the joining gap.

[0062] Due to this small thickness and the small amount of material, the joining process can be carried out in a process-compliant manner despite the sensor section 6.

[0063] In the cross-section shown, it can be seen that the sensor section 6 has a base layer 7, via which the sensor section 6 is printed on the contact partner, here the pole 3a. As a functional layer, the sensor section 6 has a printed test structure 8, which is described in more detail below and which was printed using a conductive ink or paint. Optionally, the sensor section 6 is provided in some areas with a cover layer 9, which electrically insulates the test structure 8, at least in sections, from the contact partner resting on it, in this exemplary embodiment from the contact element 4. The base layer 7 can either be designed as an adhesion improvement and / or can form electrical insulation from the other contact partner, here the pole 3a.The base layer 7 and / or the cover layer 9 can be formed only in sections and, in particular, leave the joining area 5 exposed in order to avoid any influence on the quality of the joined joining area due to material admixture by the base layer 7 and / or cover layer 9. As long as the material of the base layer 7 and / or cover layer 9 is easy to join and does not have a negative influence on the quality of the joined joining area 5, the base layer 7 and / or cover layer 9 can also be applied over the entire surface.

[0064] The Fig. 3 a - f show various embodiments of the sensor section 6. The sensor section 6 has two contact areas 10 a, b via which a sensor signal can be derived from the sensor section 6.

[0065] For example, and as in the Fig. As can be seen in Figure 2, the battery assembly 1 comprises an evaluation device 11, which can contact the contact areas 10a, b in order to derive the sensor signal. The sensor section 6 is designed in particular as a passive sensor section, so that the evaluation device 11 applies a test voltage and / or a test current to it, for example.

[0066] The sensor section 6 has at least one measuring area 12, wherein the measuring area 12 is arranged congruently and / or overlapping and / or directly adjacent to the joining area 5. Because the measuring area 12 is arranged directly at the joining area 5, the latter can be checked locally by the measuring area 12. The check can be carried out both in the joined state and in the contacting state of the battery arrangement 1. The Fig. 3 a shows the general structure of the sensor section 6. The dashed lines between the measuring area 12 and the contact areas 10 a, b indicate that further electrical elements, in particular resistors, or measuring areas 12 can be realized in the sensor section 6.

[0067] The Fig. Figure 3b shows a schematic representation of a first possible implementation of the measuring region 12. The measuring region 12 has a first electrode structure 13 and a second electrode structure 14, wherein the first electrode structure 13 is conductively connected to the contact region 10a and the second electrode structure 14 is conductively connected to the contact region 10b. In the embodiment of the Fig. 3 b, the electrode structures 13, 14 are each formed as a rectangular electrode section. Optionally, the electrode section can also be adapted to the shape of the joining area 5 and, for example, be cut out semicircularly.

[0068] In the joined state, the contacting partners are thus positioned adjacent to one another in the joining area 5, ready for joining and / or suitable for joining, with the contacting partner electrically connecting the electrode structures 13, 14 to one another, so that the joining state can be verified by a continuity test. As soon as the evaluation device 11 detects an electrical continuity between the electrode structures 13, 14, the contacting partners are positioned ready for joining and / or suitable for joining.

[0069] In the contacting state, the joining region 5 is joined in a materially bonded manner, with the electrode structures 13, 14 being electrically conductively connected to one another by the materially bonded joining region 5. In this way, the evaluation device 11 can also check the contacting state of the battery assembly 1 in the joining region 5 by means of a continuity measurement.

[0070] The Fig. Figure 3c shows an alternative embodiment, wherein the first electrode structure 13 has a plurality of individual electrode sections 15. The individual electrode sections 15 extend parallel to one another. This configuration results in less interference with the joining region 5 by the first electrode structure 13.

[0071] In the Fig. 3 d shows an embodiment in which both electrode structures 13, 14 have corresponding electrode sections 15.

[0072] Both in the embodiment in the Fig. 3 c as well as in the embodiment in the Fig. 3 d, individual contact pairs 16 are formed, wherein the individual contact pairs 16 can be electrically connected independently of one another by the joining region 5 and / or the contacting partner. In the embodiment in the Fig. 3 c, a single contact pair 16 is formed by a single electrode section 15 of the first electrode structure 13 and the opposite second electrode structure 14. In the embodiment in the Fig. 3 d, a single contact pair 16 is formed by a single electrode section 15 of the first electrode structure 13 and an opposite single electrode section 15 of the opposite second electrode structure 14.

[0073] In the Fig. 3 e, each of the electrode sections 15 of the first electrode structure 13 has a resistor 17, so that in the joining state and / or in the contacting state, several of the individual contact pairs 16 are conductively connected to one another and thereby form a parallel circuit with the individual resistors 17.

[0074] A total measuring range resistance results at the outputs of the measuring range 12, whereby the total measuring range resistance is formed by the parallel connection of the individual resistors 17. The total measuring range resistance thus depends on how many individual contact pairs 16 are conductively connected to one another.

[0075] The evaluation device 11 is designed to estimate a connection length in the joining area 5 based on the total measuring range resistance. If the connection length is short, few individual contact pairs 16 are electrically connected to one another, and the total measuring range resistance is large; this may correspond to an individual resistance 17. If the connection length is longer, more of the individual contact pairs 16 are connected to one another, resulting in a smaller total measuring range resistance. The connection length can be estimated both in the joining state and in the contacting state.

[0076] In the Fig. 3f shows an embodiment in which the second electrode structure 14 also has individual resistors 17. In this embodiment, the connection length can be better estimated because the second electrode structure 14 with the individual resistors 17 also generates a change in the total measuring range resistance depending on the connection length.

[0077] In the Fig. Figure 3g shows a further embodiment, wherein the individual resistors 17 are of different sizes and are therefore coded. By selecting the values ​​for the individual resistors 17 accordingly, not only can a connection length be estimated, but it can also be estimated which of the individual contact pairs 16 are electrically connected to one another. This allows a connection distribution to be estimated by identifying the individual contact pairs 16 that are electrically connected to one another via the total measuring range resistance.

[0078] In the Fig. 3h shows an embodiment in which the second electrode structure 14 also has coded individual resistors 17. In this embodiment, the connection distribution can be better estimated, since the second electrode structure 14 with the coded individual resistors 17 also generates a change in the total measuring range resistance depending on the connection distribution.

[0079] In the Fig. 4 shows an embodiment of the sensor section 6, which can simultaneously and / or at the same time check four joining areas 5 of the pole 3a. The sensor section 6 has four measuring areas 12, as shown in the Fig. 3 d, which are connected in series. After the first two measuring areas 12, a path resistor 19 is inserted in series in the measuring path 18 for coding the subsequent measuring path section. In the event that only one of the joining areas 5 is either not positioned correctly for joining and / or ready for joining in the joined state, the electrical path between the contact areas 10 a, b is interrupted via the path resistor 19, and the evaluation device 11 cannot measure the total section resistance dependent on the path resistance 19, so that the incorrect positioning is detected. In this case, conductive pads are arranged on the contact partner to be pressed onto the sensor section 6, which are insulated from the conductive base material of the contact partner. For example, an imprint on the contact partner to be joined is necessary.In this way, it is ensured that short circuits between the measuring areas 12 cannot occur through or via the base material of the contact partner to be pressed.

[0080] The pads thus each have an insulating base layer and an electrically conductive cover layer. In particular, the pads are each limited to a measuring area 12 or joining area 5.

[0081] The Fig. 5 shows in the same schematic representation a sensor section 6 as an embodiment with four measuring areas 12, as shown in the Fig. 3 b, wherein the measuring regions 12 are arranged in a resistor network. The resistor network has a measuring path 18 a, b, c, d for each measuring region 12, which are electrically connected in parallel to one another. In each resistance path 18 a, b, c, d there is a path resistor 19 a, b, c, d, wherein the path resistors 19 a, b, c, d are designed as different resistors. By selecting different values ​​for the path resistors 19 a, b, c, d, the measuring paths 18 a, b, c, d are coded so that the evaluation device 11 can estimate which of the joining regions 5 may be faulty in the joining state. In the event that one of the joining areas 5 is not free of defects in the joining state, the corresponding measuring path 18 a, b, c, d is switched to non-conductive by the measuring area 12, so that a changed total section resistance results at the contact areas 10, a, b.The evaluation device 11 is designed to estimate, on the basis of the total section resistance, which measuring path 18 a, b, c, d and thus which measuring region 12 is conductive and can thus estimate the manufacturing state of the battery arrangement 1 in the joining regions 5.

[0082] The Fig. 6 shows a modification of the embodiment of the sensor section 6 in the Fig. 5, wherein one of the measuring areas 12 is designed as shown in the Fig. 3 e or Fig. 3 f. In this embodiment, the sensor section 6 not only enables the determination of an absolute electrical continuity for each measuring area 12 and thus for each joining area 5, but it can also - as previously described in connection with the Fig. 3 e and Fig. 3 f - the respective connection length and / or the respective connection distribution for the measuring range 12 with the individual resistors 17 can also be estimated by the evaluation device 11.

[0083] The Fig. 7 shows a modification of the sensor section 6 in the Fig. 6, wherein the cover layer 9 is shown schematically. The sensor section 6 and in particular the measuring areas 12 are specially designed for testing in the joined state of the battery assembly 1. The measuring areas 12 are designed to be contact-capable in sections in the region of the respective joining areas 5, in that the insulating cover layer 9 has corresponding free areas 20, so that the sensor section 6, in particular the respective measuring area 12, can make electrical contact with the applied contact partner in the joined state in order to test the joined state.

[0084] In the examples in the Fig. 5 to 7, the contact partner to be pressed has a pad for each measuring area 12 and / or for each joining area 5 to prevent a short circuit. In these embodiments, the joining state can be monitored. Monitoring the contact state is not, or not entirely, meaningful due to the resulting short circuits across the contact partner carrying the measuring area 12.

[0085] The Fig. 8 shows the embodiment from the Fig. 5, wherein a further path resistor 22 a, b, c, d is arranged in front of each measuring area 12, wherein the further path resistors are configured differently. In particular, path resistors 19 a, b, c, d are arranged as trailing resistors and the further path resistors 22 a, b, c, d are arranged as leading resistors with respect to the measuring areas 12. This extended coding makes it possible to check the joining state and / or the contacting state of all measuring areas 12, in particular without the use of pads.

[0086] The Fig. 9 and Fig. 10 show the embodiments of the Fig. 6 and Fig. 7, wherein the further path resistors 22 a, b, c, d are also introduced.

[0087] The embodiment in the Fig. 10 is particularly suitable for checking the joining condition.

[0088] The Fig. 11 shows an alternative embodiment, wherein the cover layer 9 completely covers the measuring areas 12 and thereby electrically insulates them, so that an electrical connection of the measuring areas 12, in particular of the electrode structures 13, 14, can only be made after the material-to-material joining, in that the insulation of the cover layer 9 is removed by the joining process and an electrical contact is established between the electrode structures and the joining area 5 in the joined state in order to check the contact state. In the embodiment in the Fig. The additional path resistors 22 a, b, c, d are also incorporated in the contact area 11. This embodiment with a cover layer 9, which electrically insulates the measuring areas 12 from the contact partner to be pressed, is particularly suitable for testing the contact state.

[0089] In further embodiments not shown, the sensor section 6 can have measuring areas 12 with complete insulation as in the Fig. 11, and measuring areas 12 with non-contact areas as in the Fig. 7 or without a cover layer 9, so that both the joining state and the contacting state can be checked via a common sensor section 6.

[0090] It is also possible for a joining region 5 to have both a measuring region 12, which is designed to make contact for testing the joining state, and a second measuring region 12, which is rotated, for example, by 90°, and is electrically insulated for testing the contact state, arranged thereon. In this context, it can be provided that the sensor section 6 has a plurality of contact regions 10a, b, with one pair of contact regions 10a, b being assigned to the insulated measuring regions 12 and another pair of contact regions being assigned to the contact-capable measuring regions 12.

[0091] In further embodiments, the measuring range 12 can be connected both in parallel and in series. Fig.12 shows the contact element 4 in a schematic, three-dimensional representation, wherein the contact area 10 a, b or the sensor section 6 is arranged on an underside. A connection to the contact area 10 a, b or to the sensor section 6 can be printed onto the contacting partner via printing, thus making it easier to access. For example, a tapping area 21 is located on an opposite side of the contact element 4. Such a tapping area 21 can be used, for example, to use a hold-down device during the joining process to signal-connect the sensor section 6 to the evaluation device 11, so that the inspection of the manufacturing status can be easily integrated into production.

[0092] The sensor section 6 thus enables monitoring of an electrical connection point in a joining area 5 with respect to physical parameters such as contact, presence of a weld seam, positioning, temperature, etc. This allows cost- and space-efficient integration of measuring or detecting functions for individual contacts or battery cells into the sensor section 6 as a single product. Invisible or inaccessible gaps that must be closed during welding in order to define the welding process can be monitored by sensors / detection, and signals can be provided externally. Indirect process monitoring processes can be replaced or supplemented by a direct monitoring process.

[0093] Surface structures are applied to the weld area to define the contact state for the weld. These surface structures allow the "contact state" of the joining partners to be evaluated by measurement (electrical contact, pressure -> change in resistance, etc.). The conductor tracks / contact surfaces are designed in such a way that digital (yes / no) or more differentiated information about the contact or connection state is possible (resistance-coded, temperature-sensing). The electrical contact of the signals is established via a device or, for example, via the hold-down tool that presses the arrester onto the battery cell.

[0094] Conductor tracks in the area of ​​the connection point that come into contact / interaction with the component to be welded and can thus detect the state of the "zero gap" formation or report back process information such as a welding temperature, which can be recorded directly on the battery or the component to be welded. Designed in a way that makes it possible to make a metrological statement about the contact state, e.g. using resistance codes to detect the number or extent of the connection points. Surface-applied conductor tracks can be integrated on the arrester, replacing separate conductor tracks in the form of cables or ribbon cables. Printed layers are contacted during the pressing process (e.g. elastic, electrically conductive layers) or activated via the joining process (waste heat from the weld seam) or activated via a dedicated laser effect (sufficient heating for activation).

[0095] Possible benefits include: Deterministic detection of contact between battery and arrester becomes possible; sensor functions that persist beyond the welding process can be reused later to record the operating status of the product during operation; sensor cables can be largely eliminated if they are applied directly to the component surface; connections can be realized without welding, as the printed layers are sufficiently thin to be functionally ineffective in the "gap." Pre-sintered conductive layers are sufficiently robust to clamp them in the gap. List of reference symbols 1 Battery arrangement 2 batteries 3a, b Pole 4 Contact element 5 Joining area 6 Sensor section 7 Soil layer 8 Test structure 9 Top layer 10a, b Contact areas 11 Evaluation device 12 measuring range 13 first electrode structure 14 second electrode structure 15 single electrode sections 16 individual contact pairs 17 single resistors 18 a, b, c, d measuring path 19 a, b, c, d Path resistance 20 outdoor areas 21 Tapping area

Claims

[1] Battery arrangement (1) with at least one battery (2), wherein the battery (2) has at least one pole (3a) for electrically contacting the battery (2), wherein the pole (3a) forms a first contact partner, with a contact element (4) for electrically contacting the pole (3a), wherein the contact element (4) forms a second contact partner, wherein in a joining state as a first manufacturing state of the battery arrangement (1), the contact element (4) rests on the pole (3a) in at least one joining region (5) ready for joining and / or in a manner suitable for joining, and / or wherein in a contacting state of the battery arrangement (1) as a second manufacturing state, the contact element (4) is integrally connected to the pole (3a) in one and / or the at least one joining region (5), with a sensor section (6) for checking at least one of the manufacturing states of the battery arrangement (1), characterized by , that the sensor section (6) is arranged between the contact element (4) and the battery (2). [2] Battery arrangement (1) according to claim 1, characterized by that the sensor section is arranged circumferentially and / or overlapping the at least one joining area (5). [3] Battery arrangement (1) according to claim 1 or 2, characterized by that the sensor section (6) is applied to one of the contact partners at least partially or completely by coating, in particular printing. [4] Battery arrangement (1) according to one of the preceding claims, characterized by that the sensor section (6) comprises a test structure (8) applied by coating, wherein the test structure (8) is designed to be conductive at least in sections. [5] Battery arrangement (1) according to one of the preceding claims, characterized bythat the sensor section (6) has a thickness of less than 25µm, in particular less than 10µm and especially less than 1µm. [6] Battery arrangement (1) according to one of the preceding claims, characterized by in that the sensor section (6) has at least one measuring region (12), wherein the measuring region (12) is arranged circumferentially and / or congruently and / or overlapping with the joining region (5), wherein the manufacturing state of the battery arrangement (1) in the joining region can be checked in the measuring region (12). [7] Battery arrangement (1) according to claim 6, characterized by in that the measuring region (12) has a first electrode structure (13) and a second electrode structure (14), wherein the first electrode structure (13) and the second electrode structure (14) are electrically separated from one another, wherein the joining region (5) is arranged between the electrode structures (13, 14). [8] Battery arrangement (1) according to claim 7, characterized bythat the measuring region (12) for an electrical continuity measurement for testing the manufacturing state of the battery arrangement (1) is formed in the joining region (5), wherein the electrode structures (13, 14) are conductively connected to one another by the applied contacting partner and / or the joining region (5) depending on the manufacturing state. [9] Battery arrangement (1) according to one of the preceding claims 7 or 8, characterized byin that the measuring region (12) is designed for an electrical resistance measurement for checking the manufacturing state of the battery arrangement (1) in the joining region (5), wherein the electrode structures (13, 14) form a plurality of individual contact pairs (16), wherein the individual contact pairs (16) each have at least one individual resistor (17), wherein the individual contact pairs (16) are conductively connected to one another depending on the manufacturing state, so that a total measuring range resistance is formed, wherein a connection length can be estimated on the basis of the total measuring range resistance. [10] Battery arrangement (1) according to claim 9, characterized by that the individual contact pairs (16) are coded via the respective individual resistance (17) so that a connection distribution can be estimated on the basis of the total measuring range resistance. [11] Battery arrangement (1) according to one of claims 6 to 10, characterized byin that the sensor section (6) has at least two of the measuring regions (12), wherein the measuring regions (12) in the sensor section (6) are interconnected in such a way that a total section resistance is formed, wherein the manufacturing state of the battery arrangement (1) in the respective joining region (5) with the different measuring regions (12) can be estimated on the basis of the total section resistance. [12] Battery arrangement (1) according to claim 11, characterized by that the measuring areas (12) are arranged in a resistance network and / or form a resistance network, wherein in the resistance network different measuring paths (18, 18a, b, c, d) and / or measuring path sections are coded by path resistors (19, 19a, b, c, d, 22a, b, c, d) and / or the measuring areas (12) have the individual resistors (17), so that the total section resistance is formed. [13] Battery arrangement (1) according to claim 12, characterized bythat each measuring path (18, 18, b, c, d) and / or measuring path section has a path resistance (19, 19 a, b, c, d, 22 a, b, c, d) upstream of the measuring area (12) and downstream of the measuring area (12), wherein the path resistances (19, 19 a, b, c, d, 22 a, b, c, d) of the measuring paths (18, 18 a, b, c, d) are designed differently, so that the respective measuring path (18, 18, b, c, d) is uniquely coded via the combination of the path resistances and / or so that the joining state of the joining areas (12) can be deduced from the total resistance. [14] Battery arrangement (1) according to one of the preceding claims, characterized byin that the sensor section (6) is designed to check the joining state, wherein the sensor section (6) is contact-capable at least in sections, so that the sensor section (6) can make electrical contact with the applied contacting partner in the joining state in order to check the joining state and / or in that the sensor section (6) is designed to check the contacting state, wherein the sensor section (6) is at least in sections electrically insulated in the contacting state, so that the sensor section (6) is electrically insulated from the applied contacting partner in the joining state and is electrically connected in the contacting state in order to check the contacting state. [15] Battery pack, characterized by a plurality of battery assemblies (1) according to one of the preceding claims. [16] Method for checking the manufacturing state of a battery assembly (1) according to one of claims 1 to 14, wherein the battery assembly (1) is brought into one of the manufacturing states and the manufacturing state of the battery assembly (1) is checked via the sensor section (6).

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