Measuring device for inline measurement of the adhesion strength of a coating on an electrode, manufacturing plant for an electrode, and method for checking the adhesion strength of a coating on an electrode.

Abstract

The invention relates to a measuring device (22) for inline measurement of the adhesion strength of a coating (16) of an electrode (12), comprising two deflecting rollers (28) and a measuring roller (30), which are aligned with their respective central axes parallel to each other, wherein the measuring roller (30) is configured to be moved in a lateral direction (32) perpendicular to a longitudinal extension direction of the central axes relative to the deflecting rollers (28), wherein the deflecting rollers (28) are configured to be positioned against the same side of the electrode (12) and the measuring roller (30) is configured to be positioned against the other side of the electrode (12), whereby by moving the measuring roller (30) the electrode (12) can be positioned around the measuring roller (30), whereby the electrode (12) has a bend in a test area defined by a radius of the measuring roller (30), and comprising an optical defect detection device (34).which is designed to optically detect and evaluate the area of ​​the electrode (12) to be tested.

Description

[0001] The invention relates to a measuring device for inline measurement of the adhesion strength of a coating of an electrode, a manufacturing plant for an electrode for a vehicle battery and a method for checking the adhesion strength of a coating of an electrode.

[0002] From DE 11 2022 130 119 A1, an adhesion tester for determining the adhesion strength of a coating on an electrode of a motor vehicle battery is known. The adhesion tester comprises a test plunger designed to be attached to the coating under test. Furthermore, the adhesion tester comprises a spring assembly in which a spring force can be generated, and a clamping device by means of which the spring force in the spring assembly can be adjusted and which is designed to transmit the spring force to the test plunger. This causes the test plunger to be pulled by the spring force, and the adhesion strength can be determined based on the spring force generated in the spring assembly when the coating detaches from the electrode.

[0003] The object of the present invention is to provide a solution by which the adhesive strength of a coating on an electrode can be determined particularly easily and promptly after the electrode has been produced.

[0004] This problem is solved according to the invention by the subject matter of the independent claims. Further possible embodiments of the invention are disclosed in the dependent claims, the description, and the figures. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0005] The invention relates to a measuring device for the inline measurement of the adhesion strength of a coating on an electrode. An electrode is an electrical conductor that interacts with a counter electrode and with a medium located between the two electrodes. Electrodes comprise electrical conductors, which are usually made of a metal or graphite. The electrode is specifically designed for use in a battery, particularly in a vehicle battery. For example, the electrode can be intended for use as part of a lithium-ion battery cell. During the manufacturing process, the electrode is produced in the form of an electrode strip, which is cut according to requirements or according to the specified size of the electrode to be produced.To manufacture the electrode, an electrode material, such as an electrode paste or electrode slurry, can be applied as a coating to a carrier substrate, particularly a carrier film. The adhesion strength of this coating to the carrier substrate influences the quality of the electrode. Therefore, during electrode manufacturing, the adhesion strength of the coating to the carrier substrate must be checked. If the determined adhesion strength falls below a predefined limit, then the electrode production parameters must be adjusted, or already produced sections of the electrode strip where the adhesion strength is below the predefined limit must be rejected.To minimize scrap during electrode production by quickly addressing coating adhesion issues, the coating's adhesion strength is measured inline. The measuring device is integrated directly into the production line. Inline measurement takes place immediately during manufacturing, directly within the process. Based on the data obtained from the measuring device, electrodes can be selectively rejected if the coating does not meet specifications. This rejection process can be automated. The measuring device is therefore designed to be an integral part of an electrode manufacturing system. Inline measurement allows for immediate verification of the coating's adhesion strength after the substrate has been coated or after the coating has dried.

[0006] The measuring device comprises two deflection rollers and a measuring roller, whose respective central axes are aligned parallel to each other. The measuring roller is configured to move laterally relative to the deflection rollers in a direction perpendicular to the longitudinal direction of the central axes. The deflection rollers are configured to be positioned against the same side of the electrode. The measuring roller is configured to be positioned against the opposite side of the electrode, allowing the electrode to be positioned against and around the measuring roller by moving it laterally and between the deflection rollers. This results in the electrode exhibiting a bend, defined by the radius of the measuring roller, within the area to be tested. The measuring device further comprises an optical defect detection device, which is configured to optically detect and evaluate the area to be tested.This means that the defect detection device, with its detection range, is aligned with the area of ​​the electrode to be inspected. For example, the optical defect detection device can include a camera for optically detecting the area of ​​the electrode to be inspected. It is possible that the electrode is moved relative to the measuring roller during the optical detection of the area to be inspected. If the electrode is moved relative to the measuring roller during the optical detection and inspection of the coating, then a particularly long area of ​​the electrode can be examined within the procedure. By positioning the deflection rollers and the measuring roller against opposite sides of the electrode, the deflection rollers ensure that the electrode is reliably and evenly contacted with the measuring roller, especially with the outer surface of the measuring roller.For this purpose, it is provided that, in the direction of electrode movement in which the electrode is moved by the measuring device during inline measurement, and which is perpendicular to both the lateral direction and the longitudinal direction of the rollers' central axes, one of the deflection rollers is positioned in front of the measuring roller and the other deflection roller is positioned behind the measuring roller. This means that when the measuring roller moves laterally relative to the deflection rollers, it passes between the deflection rollers, thereby receiving the electrode or reliably applying it to the electrode. This achieves the electrode wrapping around the measuring roller.By adjusting the distance between the deflection rollers in the direction of movement, or by adjusting the lateral path traveled by the measuring roller relative to the deflection rollers, the wrap angle of the measuring roller can be set during inline measurement with the electrode. The smaller the distance between the deflection rollers in the direction of electrode movement, and the further the measuring roller is moved laterally from the deflection rollers, the tighter the wrap angle of the measuring roller becomes. This measuring device enables particularly simple and precise inline measurement of the adhesion strength of the electrode coating.

[0007] In a possible further development of the invention, the measuring device includes a marking device configured to mark the beginning and end of the section of the electrode that has been bent with the specified bend. Bending the electrode with the specified bend causes damage to the electrode coating. Inline measurement is, in particular, a destructive test of the coating's adhesion strength. Thus, once a section of the electrode has been subjected to the specified bend, it can be assumed that the coating in that section has been damaged. Consequently, this section must be reliably removed from the production process. This can be ensured by the marking device reliably marking these sections.

[0008] In this context, it may be particularly useful for the marking device to be configured to mark the area with a mark that characterizes a result of the evaluation. This mark, which characterizes the evaluation result, makes it especially easy to determine the result for the marked area. For example, if the mark indicates that the determined adhesion strength of the coating in that area does not meet a specified adhesion strength, then after reading this mark, at least that area, and at least one other area of ​​the electrode produced with the same production parameters as the rejected area, can be automatically rejected. This eliminates the risk of further processing or...The risk of using a defective electrode, whose coating does not meet the required adhesion strength, in the manufacture of a battery should be kept to a minimum.

[0009] In a further possible embodiment of the invention, the measuring device comprises a heating element configured to heat the measuring roller, at least in certain areas, and a thermographic camera configured to capture the area to be tested. The thermographic camera can also be referred to as a thermal imaging camera. Thermography is an imaging technique for displaying the surface temperature of objects. The intensity of infrared radiation emanating from a point is interpreted as a measure of its temperature. The thermographic camera converts the infrared radiation, invisible to the human eye, into electrical signals. From these signals, evaluation electronics can generate a false-color image that characterizes the respective measured temperatures of the object.Using a thermographic camera, a detachment of the coating from the substrate can be detected particularly easily and reliably based on changes in the heat conduction of the electrode.

[0010] In a further possible embodiment of the invention, the measuring roller comprises a roller core and a roller body, which is interchangeably mounted on the roller core and provides a cylindrical surface for the measuring roller. The roller body of the measuring roller can be interchangeable. For example, several roller bodies with different radii can be available, and depending on a predetermined electrode bend in the area to be tested, one of the roller bodies can be selected and mounted on the roller core. This allows for particularly easy adjustment of different electrode bends during inline measurement, especially depending on the coating adhesion being tested.

[0011] In a further possible embodiment of the invention, the measuring roller has a radius of at least 3.5 mm and at most 200 mm, and in particular a radius of at least 10 mm and at most 60 mm. In a cylindrical cell, the smallest radius of an electrode winding in the cell core is 3.5 mm. By selecting a measuring roller with a particularly small radius, especially one of approximately 3.5 mm, the maximum stress on the electrode occurring in a cylindrical cell can be tested. By selecting the measuring roller with a radius of approximately 200 mm, the minimum electrode requirements for further processing can be tested. In particular, the bending generated at the electrode, which results from the radius of the measuring roller of at least 10 mm and at most 60 mm, represents an ideal test range.

[0012] The invention further relates to a manufacturing system for an electrode for a vehicle battery. The manufacturing system comprises a coating unit configured to apply a coating to a carrier substrate, in particular a carrier film, for the production of the electrode. The manufacturing system further comprises a drying unit configured to dry the coating applied to the carrier substrate. The manufacturing system also includes a measuring device as already described in connection with the measuring device according to the invention. The measuring device is configured to test the adhesion strength of the dried coating inline. Thus, in the electrode manufacturing process, the carrier substrate is first coated, then the coating is dried, and finally the adhesion strength of the coating is checked.The manufacturing system thus enables inline testing of the coating's adhesion strength particularly quickly, especially immediately after the coating has dried, allowing for a particularly fast response to coating quality deficiencies with very little rejects.

[0013] In this context, it is specifically intended that the manufacturing plant includes a reject device designed to automatically reject a section of the electrode that has been marked as having been inspected by the measuring device. For example, the marking device of the measuring device may have marked the beginning and end of the section of the electrode that was bent at the specified angle for the inspection. As a result of bending this section of the electrode, the coating in that area has been damaged. The reject device ensures that this section, bent at the specified angle, is reliably and automatically sorted out.The ejection device automatically removes the area of ​​the electrode that has undergone destructive testing, in order to prevent this area of ​​the electrode, in which the coating has been destroyed, from being further processed, for example into a vehicle battery.

[0014] The invention further relates to a method for checking the adhesion strength of a coating on an electrode. In particular, the method is carried out using a measuring device as already described in connection with the device according to the invention. In the method, the electrode is guided between two deflection rollers and a measuring roller. The deflection rollers and the measuring roller are aligned parallel to each other with their respective central axes. The electrode is guided in the direction of movement between the deflection rollers and the measuring roller, with the deflection rollers being positioned against the same side of the electrode and the measuring roller against the opposite side of the electrode. Thus, the deflection rollers and the measuring roller are positioned on opposite sides of the electrode in the lateral direction.In this process, the electrode is placed around the measuring roller, causing it to partially encircle the roller. This is achieved by moving the measuring roller laterally relative to the deflecting rollers in a direction perpendicular to the longitudinal direction of the central axes. As a result, the electrode exhibits a bend in the area to be tested, defined by the radius of the measuring roller. The process also incorporates an optical defect detection device for the optical detection and evaluation of the area under test. This method enables a particularly simple and reliable inline measurement of the adhesion strength of the electrode coating.

[0015] In this context, it may be particularly suitable that, during the inspection of the area to be tested using the defect detection device, the measuring roller is encircled by the electrode within an angular range of 1° to 180°, especially within an angular range of 45° to 160°. By adjusting the degree of encirclement of the measuring roller with the electrode, the bending of the electrode can be precisely controlled. The greater the degree of encirclement, and thus the larger the angular range of the electrode's encirclement, the greater the bending of the electrode in the area to be tested when it is pressed against the measuring roller, given a specific radius of the measuring roller. By encircling the measuring roller within the angular range of 45° to 160°, it can be ensured that, firstly, a particularly long section of the electrode, in the direction of movement, is subjected to the predetermined bending, and secondly, that the predetermined bending can be precisely controlled.

[0016] Further features of the invention may become apparent from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures themselves, can be used not only in the combinations specified, but also in other combinations or on their own, without departing from the scope of the invention.

[0017] The drawing shows in: Fig. 1 a schematic view of a manufacturing plant for an electrode for a vehicle battery; Fig. 2 a schematic top view of an area of ​​the electrode which has been bent for the purpose of carrying out a measurement of adhesion strength; Fig. 3 a schematic partial view of the manufacturing plant, in which a measuring device of the manufacturing plant is shown in an initial state; Fig. 4 a schematic partial view of the manufacturing plant, showing the measuring device in an intermediate state; and Fig. 5 A schematic partial view of the manufacturing plant, showing the measuring device in a measuring state.

[0018] In the figures, identical and functionally equivalent elements are provided with the same reference symbols.

[0019] The drawing shows in Fig. 1. A manufacturing plant 10 for producing an electrode 12 for a vehicle battery of a motor vehicle. For the production of the electrode 12, a carrier substrate 14 must be provided with a coating 16 on at least one side. In this case, the carrier substrate 14 is to be provided with a coating 16 on opposite sides and thus on both sides. This coating 16 is, in this case, an electrode paste or an electrode slurry. For each side of the carrier substrate 14 to be coated, the manufacturing plant 10 comprises a coating device 18, a drying device 20, and a measuring device 22. The respective coating device 18 includes, in particular, at least one slot nozzle by means of which the carrier substrate 14, which is in particular a carrier film, is to be provided with the coating 16.The respective drying unit 20 is configured to dry the coating 16 applied to the carrier substrate 14. This means that, as part of the electrode 12 manufacturing process, the respective coating 16 applied to the carrier substrate 14 is dried by means of the respective drying unit 20. The respective measuring device 22 is configured to test the adhesion strength of the respective coating 16 applied to the carrier substrate 14 inline. Here, it is provided that the electrode 12 successively passes through one of the coating units 18, then the respective drying unit 20, and then the respective measuring device 22 for the application of the coating 16 to one side in a direction of movement 24. For the in . Fig. The bidirectional coating 16 shown in Figure 1 passes through the carrier substrate 14 first through a first coating unit 18, then the first drying unit 20, then the first measuring device 22, then the second coating unit 18, then the second drying unit 20, and finally the second measuring device 22. An alternative arrangement of the respective measuring devices 22 can be after a calendering unit and / or after a cutting unit in the direction of movement 24.

[0020] The respective measuring devices 22 are designed to perform a destructive test of the adhesion strength of the respective coating 16 being tested. During the adhesion strength test, cracks 26 may occur in the coating 16, as shown in the top view of the coating 16 being tested. Fig. 2 can be identified so that, after inspection, at least the area of ​​the electrode 12 subjected to inspection by the measuring device 22 is to be rejected and not further processed into a battery cell, for example, for a vehicle battery. For this purpose, the manufacturing plant 10 can include a rejection device (not shown in the figures) which is configured to automatically reject the area of ​​the electrode 12 that is marked as having been inspected by the respective measuring device 22. This marking can be applied to the electrode 12 by means of a marking device of the respective measuring device 22.This marking device can be configured to mark a beginning and an end of that area of ​​the electrode 12 which has been subjected to testing or which has been bent with a predetermined bend for the purpose of carrying out the test and which may have been destroyed as a result.

[0021] In the Fig. 3, Fig. 4 to Fig. Figure 5 shows an enlarged section of the manufacturing plant 10. Each section shows a part of the drying device 20 and the measuring device 22, which is arranged behind the drying device 20 in the direction of movement 24 of the electrode 12. Fig. 3, Fig. 4 to Fig. Figure 5 shows the measuring device 22 in different states. Here, the measuring device 22 is in Fig. 3 in an initial state, in Fig. 4 in an intermediate state and in Fig. Figure 5 shows the measuring device 22 in a verification state. The measuring device 22 comprises two deflection rollers 28 and one measuring roller 30. Here, it is provided that the two deflection rollers 28 are each arranged on the side of the carrier substrate 14 on which the coating 16 is applied. The measuring roller 30 is, as shown in the Fig. 3, Fig. 4 to Fig. 5 can be particularly well detected, on the side of the carrier substrate 14 where the coating 16 is not applied. The deflection rollers 28 are thus arranged on the same side of the electrode 12. The measuring roller 30 and the deflection rollers 28 are arranged on opposite sides of the electrode 12. In the Fig. In the initial state shown in Figure 3, the electrode 12 is moved in a lateral direction 32 perpendicular to the direction of movement 24 between the deflecting rollers 28 and the measuring roller 30. With respect to the direction of movement 24, the measuring roller 30 is arranged between the deflecting rollers 28. The measuring roller 30 is configured to move in the lateral direction 32 relative to the deflecting rollers 28, particularly in the direction of the side on which the deflecting rollers 28 are arranged with respect to the electrode 12. In the interaction of the Fig. 3 and Fig. Figure 4 shows how the measuring roller 30 is moved between the deflecting rollers 28 by movement in the lateral direction 32, thereby bringing the electrode 12 into contact with the measuring roller 30. The further the measuring roller 30 is moved in the lateral direction 32, the greater the area around the measuring roller 30 with the electrode 12. By bringing the electrode 12 into contact with a surface of the measuring roller 30, the electrode 12 is bent, with the curvature or radius of the bend being determined by a radius of the measuring roller 30. In this case, the measuring roller 30 comprises a roller core and a roller body, which is interchangeably mounted on the roller core and provides a surface of the measuring roller 30. This roller body is selected from several available roller bodies depending on a predetermined radius for the measuring roller 30.This radius for the measuring roller 30 can in turn be specified depending on a predetermined, achievable bend of the electrode 12. In the case of... Fig. Figure 5 shows the measuring device 22 in its test state, in which an optical defect detection device 34 of the measuring device 22 is aligned with its viewing area on a test area of ​​the electrode 12 which has the specified bend, whereby this test area can be optically detected and evaluated by means of the optical defect detection device 34.

[0022] The present arrangement provides that the measuring roller 30 can be heated, at least in certain areas, by means of a heating device of the measuring device 22, whereby a thermal imaging camera of the measuring device 22 can detect detachment of the coating 16 from the substrate 14 based on the thermal conductivity properties of the electrode 12. The thermal imaging camera can be part of the optical defect detection device 34. The thermal imaging camera can visualize detachments of the coating 16 from the substrate 14 based on changes in thermal conductivity.

[0023] The measuring device 22 thus comprises a system of three rollers that generate a shearing of the coating 16, thereby enabling the testing of a mandrel bending radius of the electrode 12. Furthermore, the measuring device 22 includes the optical defect detection device 34 for identifying cracks 26 in the coating 16. Immediately after the test has been carried out, the marking device can mark the inspected area of ​​the electrode 12, in particular with a specific code, which allows for the rapid identification and rejection of at least one area of ​​the electrode 12 if the adhesion strength of the coating 16 does not meet specified requirements.

[0024] The measuring device 22, which can also be referred to as a test module, performs a destructive test by applying a defined mechanical load to a small, precisely defined area of ​​the coating 16. The measuring roller 30 with a predetermined radius is used as a test tool to test a bending radius of the coating 16. The measuring roller 30 used here has a radius of at least 3.5 mm and at most 200 mm. In particular, the measuring roller 30 has a radius of at least 10 mm and at most 60 mm. Full engagement of the measuring roller 30 can be achieved by reaching a specific degree of wrap around the measuring roller 30 with the electrode 12. For this purpose, it is provided that during the inspection of the area to be inspected by means of the defect detection device 34, the measuring roller 30 is enclosed by the electrode 12 in an angular range of 1° to 180°, in particular in an angular range of 45° to 160°.

[0025] The measuring device 22, designed for inline measurement and used to check the adhesion strength of electrode coatings in lithium-ion batteries, enables particularly good quality assurance during a manufacturing process and reduces rejects. The measuring device 22 allows the adhesion strength of the coating 16 to be checked immediately after it has dried and before the electrode 12 is wound onto the coating, thus enabling early detection and correction of defects. The measuring device 22 therefore offers a precise, destructive solution for early quality control, thereby enabling particularly efficient production and high quality of lithium-ion batteries manufactured from the electrode 12.

[0026] A mandrel bending radius, which is an important indicator of the flexibility and adhesion of the coating 16, is typically tested at-line, meaning that the electrode 12 is removed from the production process and tested separately. This process is time-consuming and cannot be performed continuously during production. The adhesion strength of the coating 16 is usually evaluated by destructive testing, in which samples of a coated film are taken and physically stressed until failure. While this method provides accurate data on adhesion strength, it results in material loss and does not allow for real-time monitoring or immediate adjustment of production parameters. Furthermore, this creates the problem that the coating 16 cannot be tested quickly enough in the system after drying to effectively optimize dryer profiles.This can lead to a delayed response to quality problems and impair the efficiency of the production process.

[0027] Despite the destructive nature of the measurement, the measuring device 22 enables precise marking of the tested area of ​​the electrode 12, allowing for its exact rejection and thus preventing scrap. The measuring device 22 allows for inline application, resulting in particularly high production efficiency and excellent quality assurance.

[0028] Measuring device 22 is a testing system that can be integrated into a production line and thus into the manufacturing plant 10. It is designed to destructively test the adhesion strength of electrode coatings and precisely mark the tested area of ​​the electrode 12, allowing it to be removed without material loss. Measuring device 22 creates a defined bending radius on the electrode 12 and precisely marks the tested area for subsequent removal. This enables the acquisition and correlation of test data with the markings for excellent traceability. Removal of the marked areas of the electrode 12 can be automated without disrupting the production flow. These measures enable efficient quality control and process optimization directly within the production line.By integrating the measuring device 22 into the production system 10, new materials or films can be introduced as electrodes 12 particularly quickly, as the adhesion strength can be checked in real time. This results in a significant reduction in material and time losses, since non-conforming areas of the electrode 12 can be identified and removed immediately without having to cut the electrode 12. The measuring device 22 enables repeated testing during the coating process 16 without having to cut the electrode 12, which would otherwise lead to considerable effort, long setup times, and significant disruptions in downstream processing. Since subsequent processes require continuously processable semi-finished products, the measuring device 22 contributes to increasing the efficiency of the entire production chain and ensuring product quality.

[0029] In production plant 10, the measuring device 22 is strategically positioned after the drying unit 20 and after a basis weight measurement, but before a laser marking and before a surface defect detection unit. This surface defect detection unit is a test module distinct from the optical defect detection unit 34, and in particular, a redundant test module. The aforementioned arrangement of the measuring device 22 in production plant 10 allows the adhesion strength of the coating 16 to be tested directly after a drying process. An alternative possible position for in-line adhesion measurement, and thus for positioning the measuring device 22 in production plant 10 along the production line for the electrode 12, is after a calendering / cutting process.

[0030] The measuring device 22 performs the destructive test by applying a defined mechanical load to a small, precisely defined area of ​​the coating 16.

[0031] Overall, the invention shows how an inline adhesion strength measurement system can be implemented in the manufacture and processing of electrodes 12 for lithium batteries. Reference symbol list 10 Production plant 12 electrode 14 Carrier substrate 16 coating 18 Coating equipment 20 drying equipment 22 Measuring device 24 Direction of movement 26 cracks 28 Deflection roller 30 Measuring roller 32 Side direction 34 optical defect detection device QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 11 2022 130 119 A1

[0002]

Claims

[1] Measuring device (22) for inline measurement of the adhesion strength of a coating (16) of an electrode (12), - with two deflection rollers (28) and a measuring roller (30), which are aligned with their respective central axes parallel to each other, wherein the measuring roller (30) is configured to be moved in a lateral direction (32) perpendicular to a longitudinal extension direction of the central axes relative to the deflection rollers (28), wherein the deflection rollers (28) are configured to be placed against the same side of the electrode (12) and the measuring roller (30) is configured to be placed against the other side of the electrode (12), whereby by moving the measuring roller (30) the electrode (12) can be placed around the measuring roller (30), whereby the electrode (12) has a bend defined by a radius of the measuring roller (30) in an area to be tested, and - with an optical defect detection device (34) which is designed to optically detect and evaluate the area of ​​the electrode (12) to be tested. [2] Measuring device (22) according to claim 1, characterized by a marking device which is designed to mark a beginning and an end of that part of the electrode (12) which has been bent with the specified bend. [3] Measuring device (22) according to claim 2, characterized by that the marking device is set up to mark the area with a mark that characterizes a result of the evaluation. [4] Measuring device (22) according to one of the preceding claims, characterized by a heating device which is designed to heat the measuring roller (30) at least in certain areas, and a thermographic camera which is designed to detect the area to be tested. [5] Measuring device (22) according to one of the preceding claims, characterized by , that the measuring roller (30) comprises a roller core and a roller body which is interchangeably mounted on the roller core and provides a cylindrical surface of the measuring roller (30). [6] Measuring device (22) according to one of the preceding claims, characterized by , that the measuring roller (30) has a radius of at least 3.5 millimeters and at most 200 millimeters, in particular a radius of at least 10 millimeters and at most 60 millimeters. [7] Manufacturing plant (10) for an electrode (12) for a vehicle battery, comprising a coating device (18) which is configured to provide a carrier substrate (14), in particular a carrier film, with a coating (16) for the production of the electrode (12), comprising a drying device (20) which is configured to dry the coating (16) applied to the carrier substrate (14), and comprising a measuring device (22) according to one of the preceding claims which is configured to test the adhesion strength of the dried coating (16) inline. [8] Manufacturing plant (10) according to claim 7, characterized by a rejection device which is designed to automatically reject an area of ​​the electrode (12) which is marked as having been checked by means of the measuring device (22). [9] Method for checking the adhesion strength of a coating (16) of an electrode (12), in which - the electrode (12) is guided between two deflection rollers (28) and a measuring roller (30), which are aligned with their respective central axes parallel to each other, wherein the deflection rollers (28) are placed against the same side of the electrode (12) and the measuring roller (30) is placed against the other side of the electrode (12), - the electrode (12) is placed around the measuring roller (30) by moving the measuring roller (30) in a lateral direction (32) perpendicular to a longitudinal extension direction of the central axes relative to the deflecting rollers (28), whereby the electrode (12) has a bend in an area to be tested which is defined by a radius of the measuring roller (30), and - the area to be inspected is optically detected and evaluated by means of an optical defect detection device (34). [10] Method according to claim 9, characterized by, that during the inspection of the area to be inspected by means of the defect detection device (34) the measuring roller (30) is enclosed by the electrode (12) in an angular range of 1° to 180°, in particular in an angular range of 45° to 160°.

Images