METHOD FOR LEAK TESTING ON AN ELECTRICAL BUSBAR ASSEMBLY AND USE OF AN IMAGING X-RAY METHOD FOR LEAK TESTING

Abstract

A method for leak testing of an electrical busbar assembly is proposed. The method comprises providing a busbar assembly (100) with at least one busbar (110, 120) and a heat-shrink tube (140) that surrounds at least one busbar (110, 120) at least partially and whose longitudinal end section is shrunk onto the busbar (110, 120). The method also includes checking the longitudinal end section for the presence of air inclusions between the heat-shrink tube (130) and the busbar (110, 120) using an X-ray imaging technique. Furthermore, the use of an X-ray imaging technique for leak testing is proposed.

Description

Technical field

[0001] The present invention relates to a method for leak testing of an electrical busbar assembly. The invention further relates to the use of an X-ray imaging method for leak testing of an electrical busbar assembly. The invention also relates to an electrical busbar assembly. State of the art

[0002] In practice, it is desirable to insulate an electrical busbar assembly used to conduct electric current, for example, for technical and / or safety reasons, e.g., to protect against electrical hazards to people, as short-circuit protection, to protect the busbar assembly from external influences, etc. It may also be desirable to seal the busbar assembly.

[0003] To verify the insulation and / or sealing or tightness of the busbar assembly, it would be conceivable to perform a pressure test using overpressure or underpressure and thereby conclude the insulation quality and / or tightness. It is also conceivable that, for example, a gaseous medium could be introduced into insulation, e.g., under an insulating jacket, the escape of the gaseous medium from there detected, and conclusions drawn about tightness or leakage from this. For such pressure tests, a pressure chamber and / or a suitable gaseous medium could be used. Conversely, it would be desirable to find a method that does not require a pressure chamber and / or the use of a gaseous medium. Description of the invention

[0004] One object of the invention is therefore to create a means of leak testing an electrical busbar assembly using simple means.

[0005] The problem is solved by the subject matter of the independent claims. Advantageous embodiments of the invention are specified in the dependent claims, the description, and the accompanying figures.

[0006] According to a first aspect, a method for leak testing of an electrical busbar assembly is proposed. The method comprises providing a busbar assembly. The provided busbar assembly has at least one busbar. Furthermore, the provided busbar assembly has a heat-shrink sleeve. The heat-shrink sleeve surrounds the at least one busbar, at least partially. A longitudinal end section of the heat-shrink sleeve is shrunk onto the at least one busbar. The method further comprises checking the longitudinal end section for the presence of air inclusions between the heat-shrink sleeve and the busbar. The check is carried out using an X-ray imaging method.

[0007] The leak test according to the proposed method does not require an energy-intensive pressure test using overpressure or underpressure. Furthermore, the method does not require the use of, for example, gas as a test medium. Instead, the method can be performed using a commercially available X-ray-based imaging device, such as a computed tomography scanner, an X-ray machine or X-ray detector, or the like. The use of the X-ray-based imaging device allows for non-destructive external testing of the busbar assembly's leak tightness. In addition, the heat-shrink tubing provides electrical insulation for the busbar assembly, e.g., the at least one busbar. The heat-shrink tubing also protects the busbar assembly, e.g., the at least one busbar, from the ingress of media such as liquids, contaminants, or the like.

[0008] Leakage testing can be used, for example, to check and / or assess component quality, i.e., the quality of the busbar assembly. This can be done during manufacturing, quality control, etc. Leakage can refer to the tightness of the heat shrink tubing, i.e., the sealing of the busbar assembly by the tubing.

[0009] As used herein, the busbar assembly can serve to conduct and / or distribute electric current, without limitation. For example, it can serve to mechanically decouple a high-voltage busbar, e.g., a high-voltage double busbar, from connection points, e.g., a charging socket and / or battery. The busbar assembly comprises at least one busbar and the further conductive element. The at least one busbar can be designed to be at least substantially rigid or inflexible. That is, it cannot deform, at least substantially, under its own weight, disregarding long-term cold yielding. For example, the at least one busbar can be of sheet metal form. The at least one busbar can be made of an electrically conductive metallic material. For example, it can be made of an aluminum alloy, e.g.,The busbars may be made of pure aluminum or an aluminum alloy, or the like. For example, a rectangular cross-section may be provided. It has been shown that the busbar arrangement proves particularly advantageous with comparatively larger cross-sectional sizes of the at least one busbar. By way of example only, the cross-sectional size of the at least one busbar may be at least 120 mm². 2 , in particular at least 180 mm 2 , in particular at least 210 mm 2 , or about 240 mm 2 However, the busbar arrangement is also suitable for smaller cross-sectional sizes and can still offer particularly good ease of assembly and / or compensation for tolerances.

[0010] In at least some embodiments, the busbar arrangement can have at least one connecting section. In this connecting section, the at least one busbar can be connected to another conductive element. This other conductive element can, for example, be a second busbar connected to the first busbar. The connection can be, for example, a metallurgical bond, which can be achieved, for instance, by ultrasonic welding or another suitable method. Furthermore, the other conductive element can be a connecting element. This connecting element can serve to compensate for tolerances, movements, etc. Therefore, it can also be understood and described as a flexible compensating element.It can also serve to bridge the gap between the first and second busbars. The at least one connecting element can, for example, be made of an electrically conductive metal material. The connecting element can, for example, have an at least substantially elongated shape. A first end of the at least one connecting element can be connected to the first busbar and a second end of the at least one connecting element can be connected to the second busbar. At least two connecting elements can also be provided, arranged at least substantially parallel to each other. The higher mechanical flexibility of the at least one connecting element compared to the first and / or the second busbar can be understood to mean that it has greater flexibility, greater elasticity, lower strength, or the like, or is less stiff.less rigid, less hard, or the like. In other words, the first busbar may, for example, have a first mechanical flexibility, the second busbar a second mechanical flexibility, and the at least one connecting element a third mechanical flexibility, the third flexibility being greater than the first and / or the second flexibility. The mechanical flexibility of the at least one connecting element, in particular its greater mechanical flexibility compared to the first busbar and / or the second busbar, may be based on one or more material properties and / or cross-sectional properties that are accordingly different from those of the first busbar and / or the second busbar.A distance bridged by at least one connecting element between the first busbar and the second busbar can, for example, refer to a distance between respective edges, butt surfaces, narrow sides, or the like of the first busbar and the second busbar, which are arranged in a common plane or in planes approximately parallel to each other.

[0011] In the connection section, the busbar is connected to the other conductive element. For example, the busbar and the other conductive element can be bonded together. The connection can be made, for example, by ultrasonic welding or another suitable method. It may be desirable to insulate and / or seal the connection section to protect it from contact, the ingress of contaminants, air, or the like.

[0012] Heat shrink tubing can be understood as a tubular element, e.g., a hose, which, due to its material properties, can shrink radially when exposed to heat. Heat shrink tubing can serve for insulation, mechanical protection, sealing, etc., of the busbar assembly in general and / or of the at least one connecting section, as well as of any other conductive element, e.g., the connecting element, the at least one busbar, etc. The heat shrink tubing extends over the at least one connecting section. This can be understood to mean that the heat shrink tubing has a length that is at least greater than the longitudinal extent of the connecting section. For example, the longitudinal end section of the heat shrink tubing. When shrinking, the heat shrink tubing can conform very closely to the (radially) underlying surface, e.g., a surface of the at least one busbar, and / or adhere to it.This can also be facilitated by an adhesive, such as hot melt adhesive, which can be applied to the heat shrink tubing. When shrinking the tubing, a desirable characteristic is that as little or no air as possible is trapped between the inner surface of the tubing and the underlying surface. With no or very little air trapped, a large-area conformity, adhesion, etc., of the heat shrink tubing to the underlying surface can be assumed. The longitudinal end section of the heat shrink tubing then forms a barrier, at least substantially sealing, between the outer surface of the tubing and the at least one busbar, the connection section enclosed by the heat shrink tubing, etc., particularly in the axial direction. Air inclusions in the shrunk section are therefore undesirable.For example, air inclusions can create a creepage distance, at least in a certain proportion, which can lead to leaks. This means that a lower proportion of air inclusions can indicate a higher level of tightness, and conversely, a higher proportion of air inclusions can indicate a lower level of tightness. A threshold value can be predetermined to distinguish between tightness and leakage.

[0013] The term X-ray-based imaging technique and / or device can refer to any imaging procedure that uses X-rays. This can include, for example, a computed tomography (CT) scanner, an X-ray machine or X-ray detector, or similar equipment. For instance, air inclusions can be detected using an X-ray machine or X-ray detector because air absorbs little to no radiation and therefore appears dark or black in an X-ray image. Denser materials, such as the material of a busbar, appear whiter in an X-ray image. Air inclusions appear at least similarly in a CT scan.

[0014] According to further training, the tightness of a busbar assembly can be determined based on the proportion of air inclusions detected in the longitudinal end section. If a predetermined or defined proportion of air inclusions is detected using X-ray imaging, a creepage path can develop, causing the busbar assembly to leak. If no air inclusions are present, or only a small, predetermined or defined proportion, it can be assumed that the heat shrink tubing is fully shrunk onto the longitudinal end section, or that it is in full contact with the underlying surface. This means that the busbar assembly is, for example, as desired, tight. The proportion of air inclusions can be determined, for example, by manual assessment or automatically, e.g., using image recognition.

[0015] In a training course, the proportion of detected air inclusions can be compared to a limit value. If the proportion of detected air inclusions is below the limit value, the tightness of the busbar assembly can be determined. If the proportion of detected air inclusions is above the limit value, the leakage of the busbar assembly can be determined.

[0016] According to further training, the imaging procedure can be performed as a computed tomography (CT) scan. For example, air inclusions can be visually identified in a CT scan, e.g., appearing darker than denser materials, thus making air inclusions easy to detect. A standard commercially available CT scanner can be used.

[0017] Another aspect concerns the use of an imaging X-ray procedure, in particular computed tomography, for leak testing of a busbar assembly. The imaging X-ray procedure is used to check for the presence of air inclusions between a busbar and a heat-shrink tube that is partially shrunk onto the busbar. The leak tightness of the busbar assembly is determined based on the percentage of air inclusions detected.

[0018] Regarding the advantages and possible further developments of this use and / or the busbar arrangement, reference is made to the explanations under the first aspect.

[0019] Another aspect concerns an electrical busbar assembly. The busbar assembly comprises a first busbar and a second busbar. Furthermore, the busbar assembly includes a connecting element that electrically connects the first and second busbars and is mechanically more flexible than either the first or second busbar. Additionally, the busbar assembly includes a heat-shrink tube that extends over the connecting element, the longitudinal end of which is shrunk onto the first and / or second busbar.

[0020] Regarding the advantages and possible further developments of this busbar arrangement, reference is made to the explanations of the first aspect and the second aspect.

[0021] According to a further development, the heat shrink tubing can extend beyond a longitudinal end section of the connecting element and be shrunk onto the corresponding sections of the first and second busbars. For example, the busbar assembly can have an elongated shape, at least substantially, along which the heat shrink tubing extends. In the longitudinal direction, i.e., axially, starting from the connecting element, the longitudinal end section of the heat shrink tubing can extend outwards beyond a connecting section where the connecting element is joined to the respective busbar and be shrunk onto the corresponding busbar there.

[0022] In a training course, a section of heat-shrink tubing can be shrunk onto the surface of the corresponding busbars of the first and second busbars. The goal is to minimize air pockets between the inner surface of the heat-shrink tubing and the surface of the busbar. Shrinking is achieved by applying heat to the tubing.

[0023] According to a further development, at least one of the first and second busbars can have an insulating sheath. The respective insulating sheath can be connected to a corresponding longitudinal end section of the heat shrink tubing. For example, the longitudinal ends, e.g., longitudinal edges or the like, of the insulating sheath and the heat shrink tubing can be butted together or overlapping. This results in a particularly good seal of the busbar assembly and / or the connecting section.

[0024] In a further training course, the connecting element can consist of a braided band made of a metallic material. A braided band has more flexible mechanical properties than a busbar. For example, the metallic material could be a copper alloy, although other electrically conductive metallic materials are also conceivable.

[0025] According to further training, at least one braided band can have a cross-sectional size greater than 120 mm. 2 , especially larger than 160 mm 2 , for example, of about 200 mm 2 exhibit.

[0026] The aspects, designs, variations, and examples described above can, of course, be combined without this being explicitly stated. Each of the described training courses and each example is therefore optional in relation to any of the aspects, designs, variations, and examples, or even combinations thereof. This disclosure is thus not limited to the individual designs and design variations in the described order or to any specific combination of aspects and design variations. Brief character description

[0027] An advantageous embodiment of the invention is explained below with reference to the accompanying figures. These show: Fig. 1 in a top view a busbar arrangement according to an exemplary embodiment. Fig. 2 in a schematic block diagram an exemplary device for carrying out a leak test on a busbar arrangement according to an embodiment. Fig. 3 An exemplary image from an X-ray imaging procedure showing air inclusions within or radially below a shrink tube. Fig. 4 in a flowchart a method for leak testing on an electrical busbar arrangement according to an embodiment.

[0028] The figures are merely schematic representations and serve only to illustrate the invention. Identical or equivalent elements are consistently identified by the same reference numerals. Detailed description of an exemplary implementation

[0029] Fig. Figure 1 shows a schematic top view of an exemplary electrical busbar arrangement 100. This can be used to conduct and / or distribute electrical energy, such as in a motor vehicle, although its use is not limited to this.

[0030] The busbar assembly 100 comprises at least one busbar 110, 120. In at least some embodiments, the busbar assembly can have at least one connecting section 112, 122 in which the at least one busbar 110, 120 is connected to a further conductive element 130. The respective connection in the at least one connecting section 112, 122 can, for example, be a metallurgical connection, which can be achieved, for example, by ultrasonic welding or the like. For illustrative purposes only, the conductive element 130 is designed here as a connecting element between a first busbar 110 and a second busbar 120. The conductive element could also be another busbar, for example, one of the busbars 110, 120, if these were directly connected to each other.

[0031] Furthermore, the busbar assembly 100 has a heat shrink tube 140. The heat shrink tube 140 surrounds at least part of the at least one busbar 110, 120. In at least some embodiments, the busbar can have at least one connecting section 112, 122, wherein the heat shrink tube 140 can extend over the at least one connecting section 112, 122. Fig. 1. Each longitudinal end section of the heat shrink tubing 140 is marked "142" or "144". In these sections, the heat shrink tubing 140 overlaps the respective busbar 110 or 120 and is shrunk onto it. In other words, the respective longitudinal end section 142, 144 of the heat shrink tubing 140 is shrunk onto at least one busbar 110, 120.

[0032] When shrinking the heat shrink tubing 140 onto at least one busbar 110, 120 in the respective longitudinal end section 142, 144, it may be desirable for as little or no air as possible to be trapped between an inner surface of the heat shrink tubing 140 and the underlying surface, i.e., a surface of the at least one busbar 110, 120. With no air inclusion or with only a small amount of air inclusion, a desired large-area conformity, adhesion, etc., of the heat shrink tubing to the underlying surface can be assumed. With the best possible conformity, adhesion, etc., of the heat shrink tubing 140, it can be assumed that the at least one connecting section 112, 122 is adequately sealed. A proportion of air inclusions detected as present between an inner surface of the heat shrink tubing 140 and the underlying surface, i.e.,a surface of the at least one busbar 110, 120, is therefore indicative of the tightness of the busbar arrangement, and in particular of the tightness of the shrink tubing 140 or of the at least one connecting section 112, 122.

[0033] Fig. 2 in a schematic block diagram an exemplary device 200 for carrying out a leak test on a busbar arrangement, e.g. the busbar arrangement 100.

[0034] The device 200 comprises or is designed as an X-ray-based imaging device, such as a computed tomography scanner, an X-ray machine or X-ray detector, or the like. The device 200 includes, for example, an X-ray source 210, an X-ray detector 220, or the like, and optionally a data processor 230, or the like, which is shown here by way of example as a computer.

[0035] The device 200 is configured to check a section in which a heat shrink tube, e.g., the heat shrink tube 140, is shrunk onto another element, e.g., onto the at least one busbar 110, 120, for air inclusions. For example, the device 200 can be configured to check the aforementioned longitudinal end sections 142, 144 for air inclusions after they have been shrunk onto the at least one busbar 110, 122.

[0036] Fig. Figure 3 shows an exemplary image 300, which was produced using an X-ray imaging technique. Image 300 can also be referred to as an X-ray image, computed tomography image, etc., depending on the X-ray imaging technique used to generate it.

[0037] Figure 300 shows the aforementioned longitudinal end sections 142, 144 after their shrink-fitting onto at least one busbar 110, 122. The reference symbol "146" denotes air inclusions that are visually apparent in Figure 300. Since the trapped air absorbs little to no X-rays, it appears dark or black in an X-ray image. Accordingly, the air inclusions 146 are recognizable and / or identifiable from Figure 300. For example, a proportion of the air inclusions 146 could be measured or otherwise determined from Figure 300. It is also possible to determine the proportion of the air inclusions 146 in comparison to the total area of ​​the inspected section, at least semi-automatically, for example, using an image recognition algorithm, a pattern recognition algorithm, or the like.

[0038] As mentioned above, the tightness of the busbar assembly 100 can be inferred from the identified air inclusions 146. A proportion of air inclusions 146 below or up to a certain or predetermined limit value can indicate a desired tightness. A proportion of air inclusions 146 above or above a certain or predetermined limit value can indicate an undesirable leakage.

[0039] Fig. Figure 4 illustrates in a flowchart a procedure 400 for leak testing on an electrical busbar arrangement, e.g. the busbar arrangement 100.

[0040] The method comprises providing 410 a busbar assembly, e.g., the busbar assembly 100, with at least one connecting section, e.g., the connecting section 112, 122, in which a busbar, e.g., the busbar 110, 120, is connected to another conductive element, e.g., the connecting element 130, and to the other busbar 110, 120, respectively, and a heat shrink tube, e.g., the heat shrink tube 140, which extends over the at least one connecting section and whose longitudinal end section is shrunk onto the at least one busbar 110, 120. Furthermore, the method comprises checking 420 the longitudinal end section for the presence of air inclusions between the heat shrink tube and the busbar by means of an X-ray imaging method.

[0041] Based on the proportion of detected air inclusions, e.g., air inclusions 146 in Figure 300, the tightness of the busbar assembly can be determined in the longitudinal end section. Furthermore, the proportion of detected air inclusions, e.g., air inclusions 146, can be compared to a threshold value. If the proportion of detected air inclusions is below the threshold value, the tightness of the busbar assembly is determined; if the proportion of detected air inclusions is above the threshold value, the leakage of the busbar assembly is determined. As mentioned above, the imaging X-ray procedure can be performed as computed tomography.

[0042] Referring again to Fig. 1. The exemplary busbar arrangement 100 will now be described in more detail.

[0043] The busbar assembly 100 comprises a first busbar 110 with an insulating sheath 114, which is partially recessed, e.g., in section 142. The busbar assembly 100 also comprises a second busbar 120, which is spaced apart from the first busbar 110 and has an insulating sheath 124, which is partially recessed, e.g., in section 144. A distance or spacing between the first busbar 110 and the second busbar 120 can, for example, refer to a distance between respective edges, butt surfaces, narrow sides, or the like of the first busbar 110 and the second busbar 120, which are arranged in a common plane or in planes that are at least substantially parallel to each other. The first busbar 110 and / or the second busbar 120 must be designed to be at least substantially rigid or inflexible.that they cannot deform excessively under their own weight. For example, the first busbar 110 and / or the second busbar 120 can be made of sheet metal. The first busbar 110 and / or the second busbar 120 are made of an electrically conductive metal material. For example, the first busbar 110 and / or the second busbar 120 can be made of an aluminum material, e.g., pure aluminum or an aluminum alloy, or the like. The first busbar 110 and the second busbar 120 can have the same or different cross-sectional shapes and / or cross-sectional sizes. For example, a rectangular cross-section can be provided. By way of example only, the cross-sectional size of the first busbar 110 and / or the second busbar 120 can be at least 120 mm². 2 , in particular at least 180 mm 2 , in particular at least 210 mm2 , or about 240 mm 2 The busbar arrangement 100 is also suitable for smaller cross-sectional sizes.

[0044] Furthermore, the busbar assembly 100 has at least one connecting element 130. The at least one connecting element 130 electrically connects the first busbar 110 and the second busbar 120. The connecting element 130 is connected to the first busbar 110 in the connecting section 112 and to the second busbar 120 in the connecting section 122. Moreover, the at least one connecting element 130 is mechanically more flexible than the first busbar 110 and / or the second busbar 120. The greater mechanical flexibility of the at least one connecting element 130 compared to the first busbar 110 and / or the second busbar 120 can be understood to mean that the at least one connecting element 130 has greater flexibility, greater elasticity, lower strength, or the like, or is less stiff, less rigid, less hard, or the like.In other words, the first busbar can have a first mechanical flexibility, the second busbar a second mechanical flexibility, and the at least one connecting element a third mechanical flexibility, the third flexibility being greater or higher than the first and / or second flexibility. The at least one connecting element 130 serves, for example, to compensate for tolerances, movements, etc. Therefore, it can also be understood and referred to as a flexible compensating element. It can also serve to bridge the gap between the first busbar 110 and the second busbar 120. The at least one connecting element 130 is, for example, made of an electrically conductive metal material. The at least one connecting element 130 has, for example, an at least substantially elongated shape.A first end of the at least one connecting element 130 is connected to the first busbar 110 and a second end of the at least one connecting element 130 is connected to the second busbar.

[0045] The at least one connecting element 130 can, for example, be made of a copper alloy. Accordingly, the busbar arrangement 100 can comprise an arrangement and / or material combination of, for example, (first) aluminum (Al) busbar 110 - copper (Cu) connecting element 130 - (second) aluminum (Al) busbar 120. For example, the at least one connecting element 130 comprises at least one braided band made of an electrically conductive metal alloy. A braided band is inherently more flexible than a busbar. For example, the metal alloy can be a copper alloy, although other electrically conductive metal alloys are also conceivable. Fig. 1. In at least some embodiments, the at least one connecting element 130 can be directly bonded to a respective surface of the first busbar 110 and / or the second busbar 120. This respective connection can be formed, for example, by ultrasonic welding. Ultrasonic welding also allows for an Al-Cu material pairing. As in Fig. As indicated in 1, for example the ends of the connecting element 130 can be materially connected to the first busbar 110 or the second busbar 120.

[0046] Furthermore, the busbar assembly 100 includes the heat shrink tubing 140. The heat shrink tubing 140 extends over the at least one connecting section 112, 122. The respective longitudinal end sections 142, 144 of the heat shrink tubing 140 are shrunk onto the at least one busbar 110, 120. The heat shrink tubing 140 can serve for insulation, mechanical protection, sealing, etc., of the busbar assembly 100 in general, of the connecting section 112, 122, of other conductive elements, e.g., the connecting element 130, the busbar 110, 120, etc.

[0047] The aspects, designs, variations, and examples described above can, of course, be combined without this being explicitly stated. Each of the described training courses and each example is therefore optional in relation to any of the aspects, designs, variations, and examples, or even combinations thereof. This disclosure is thus not limited to the individual designs and design variations in the described order or to any specific combination of aspects and design variations. REFERENCE MARK LIST 100 electrical busbar arrangement 110 (first) busbar 112 Connecting section 114 Insulation jacket 120 (second) busbar 122 Connecting section 124 Insulation jacket 130 additional conductive element, e.g. connecting element or busbar 140 heat shrink tubing 142 longitudinal end section 144 longitudinal end section 146 Air inclusion 200 Device 210 X-ray source 220 X-ray detector 230 data processor 300 Image of an imaging X-ray procedure 400 procedures 410 Procedure step 420 Process step

Claims

[1] Method (400) for leak testing of an electrical busbar assembly, comprising: Providing (410) a busbar arrangement comprising at least one busbar and a heat shrink tube which surrounds at least one busbar at least section by section and whose longitudinal end section is shrunk onto the at least one busbar, and (420) Checking the longitudinal end section for the presence of air inclusions between the shrink tubing and the at least one busbar using an X-ray imaging technique. [2] Method according to claim 1, wherein a tightness of the busbar arrangement is determined based on a proportion of air inclusions identified as present in the longitudinal end section. [3] Method according to claim 1 or 2, wherein a proportion of air inclusions detected as present is compared with a limit value, wherein, if a proportion of air inclusions detected as present is below the limit value, the tightness of the busbar arrangement is determined and if a proportion of air inclusions detected as present is above the limit value, the leakage of the busbar arrangement is determined. [4] Method according to one of the preceding claims, wherein the X-ray imaging method is carried out as computed tomography. [5] Use of an imaging X-ray technique, in particular computed tomography, for leak testing of an electrical busbar assembly, wherein the imaging X-ray technique is used to check for the presence of air inclusions between a busbar and a shrink sleeve that is partially shrunk onto the busbar and the tightness of the busbar assembly is determined based on the proportion of air inclusions detected as being present. [6] Electrical busbar arrangement (100), comprising: a first busbar (110), a second busbar (120), a connecting element (130) that electrically connects the first busbar and the second busbar and is mechanically more flexible than the first busbar and the second busbar, and a heat shrink tube (140) which extends over the connecting element (130) and whose longitudinal end section (142, 144) is shrunk onto the first busbar (110) and / or second busbar (120). [7] Busbar arrangement according to claim 6, wherein the shrink tubing (140) extends beyond a respective longitudinal end section of the connecting element (130) and is shrunk onto the corresponding section of the first busbar (110) and the second busbar (120). [8] Busbar arrangement according to claim 6 or 7, wherein a respective longitudinal end section (142, 144) of the shrink tubing (140) is shrunk onto a surface of the corresponding first busbar (110) and second busbar (120). [9] Busbar arrangement according to one of claims 6 to 8, wherein at least one of the first busbar (110) and the second busbar (120) has an insulating sheath (114, 124) which connects to a respective longitudinal end section (142, 144) of the heat shrink tubing (140). [10] Busbar arrangement according to one of claims 6 to 9, wherein the connecting element (130) comprises a braided band made of a metal material.

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