Electrical power line having two insulating layers; battery module; and power electronics

Abstract

The invention relates to an electrical power line (1) for connecting electrical components in a motor vehicle, preferably for connecting battery elements (2) of a battery module (3), comprising a conductor (4); a first insulating layer (5) having a fabric strip (6a), a film (6b) or a paper (6c), wherein the fabric strip (6a), the film (6b) or the paper (6c) is wound around the conductor (4); and a second insulating layer (7), which is applied onto the first insulating layer (5) in the form of a powder layer in order to completely sheath the first insulating layer (5). The invention also relates to a battery module (3), to power electronics (25) and to a method for producing an electrical power line (1).

Description

[0001] Electrical conductor with two insulation layers; battery module;

[0002] Power electronics

[0003] The invention relates to an electrical power line for connecting electrical components in a motor vehicle, preferably for connecting battery elements of a battery module.

[0004] Battery-related components in a motor vehicle are required to withstand and maintain their functionality for a certain period of time in emergency situations, such as a fire in the vehicle. Exposure to very high temperatures on the electrical wiring poses the risk of a short circuit in the battery, which can have serious consequences for the vehicle components and the surrounding area. In the event of a vehicle fire, it is essential that the battery is protected against short circuits for at least a certain period of time.

[0005] The object of the present invention is to provide an electrical power line which is particularly stable and has a high level of durability.

[0006] This is achieved in an existing electrical power line in that this power line has a conductor, a first insulation layer comprising a fabric tape, an insulation film or insulation paper, wherein the fabric tape, the film or the paper is wrapped or glued around the conductor, and a second insulation layer which is applied to this first insulation layer as a powder layer to completely enclose the first insulation layer. According to the design with two insulation layers, the first insulation layer is encased by the second insulation layer, which is why the first insulation layer is protected. This creates a heavily insulated electrical power line that can withstand various influences. The electrical power line is designed such that the second insulation layer shields the first insulation layer from direct influences.These influences can include, for example, high temperatures during a fire or damage during transport or assembly. The second insulation layer acts as a kind of buffer layer between the first insulation layer and the environment, cushioning / mitigating / reducing the influences on the first insulation layer.

[0007] Advantageous embodiments are claimed in the subclaims and are explained in more detail below.

[0008] It is advantageous if the powder layer is a resin layer made of epoxy resin. This allows for a certain degree of flexibility in the electrical conduction. Epoxy resin has the advantage that the second insulation layer can be produced entirely in a cost-effective process. Compared to a second insulation layer made of plastic, cost-intensive injection molding tools are eliminated.

[0009] Furthermore, the electrical power line can be a busbar. The conductor is preferably made of a sheet metal, preferably copper.

[0010] Using a sheet metal, different cross-sectional shapes or contours can be implemented, which are preferred for the specific application of the busbar.

[0011] Particularly preferably, a cross-section of the conductor can be rectangular with sides of different lengths.

[0012] Alternatively, the cross-section can be square or round and the conductor can be formed from a cable.

[0013] It is advisable for the fabric tape to be an adhesive tape, the insulation foil to be an adhesive film, or the insulation paper to be an adhesive paper, all of which adhere self-adhesively to the outer surface / outer contour of the conductor. This simplifies the attachment of the fabric tape, foil, or paper to the conductor. Due to the self-adhesive properties, a separate fastening or adhesive layer on the conductor or fabric tape is not required, thus simplifying the construction of the electrical conductor.

[0014] Preferably, the fabric tape is wound in turns over the outside of the conductor. If the first insulation layer comprises an insulating foil or insulating paper, these can be wrapped or glued around the outer contour / outside of the electrical conductor. Furthermore, the turns can at least partially overlap / cover each other when following a longitudinal axis. This has the advantage that the conductor is completely covered by the fabric tape and there are no gaps in the longitudinal direction between the circumferential turns. This provides complete insulation in the form of the first insulation layer.

[0015] Furthermore, the fabric tape can be made of fiberglass. Fiberglass has very high heat resistance, which allows it to withstand very high temperatures for a certain period of time. This allows the electrical conductor, for example, to be used in a battery module in a motor vehicle, to temporarily prevent a short circuit in the battery module in the event of a fire.

[0016] The invention also relates to a battery module for a motor vehicle, comprising at least two battery elements which are electrically connected to one another via an electrical power line as described above.

[0017] The invention also relates to power electronics for a motor vehicle, wherein the power electronics are electrically connected to a previously described battery module by means of a previously described electrical power line.

[0018] The invention also relates to a method for producing an electrical power cable, in particular a busbar, in which, in a first step, a conductor, preferably made of copper, is formed; in a second step, the conductor is wrapped or bonded with a first insulating layer comprising a fabric tape, preferably made of glass fiber, an insulating film, or an insulating paper; and, in a third step, the first insulating layer is encased in a second insulating layer in the form of a powder coating, preferably made of an epoxy resin. Glass fiber offers the advantage of being a heat-resistant material. Overall, a heat-resistant and flexible electrical power cable can be produced in just a few process steps.

[0019] It is advisable for the fabric tape to be an adhesive tape, the insulation film to be an adhesive film, or the insulation paper to be an adhesive paper, all of which adhere self-adhesively to the outer surface / outer contour of the conductor. This simplifies the attachment of the fabric tape to the conductor. Due to the self-adhesive properties, a separate fastening or adhesive layer on the conductor or fabric tape is not required, thus simplifying the construction of the electrical cable.

[0020] It is advantageous if the fabric tape is wound in turns over the outside of the conductor. This allows for a particularly even distribution of the fabric tape along the outer contour. Preferably, the turns can at least partially overlap each other while following a longitudinal axis. This has the advantage that the conductor is completely covered by the fabric tape and no gaps form in the longitudinal direction between the circumferential turns. This ensures complete insulation in the form of the first insulation layer.

[0021] In other words, the invention relates to a busbar with a glass fiber fabric tape wound around the busbar, wherein the glass fiber fabric tape is coated with a layer of powder.

[0022] Furthermore, the invention relates to a method for producing a busbar, preferably made of copper, wherein in a first step the busbar is wrapped with a glass fiber fabric as an adhesive tape with overlapping of the adhesive tape layers and in a second step the insulation made of fabric tape is coated with powder, for example epoxy.

[0023] Various advantageous embodiments of the invention are explained in more detail below with reference to a drawing with figures.

[0024] They show:

[0025] Fig. 1 shows an electrical power line according to the invention in a sectional view,

[0026] Fig. 2 shows the electrical power line in a perspective view in a first embodiment, Fig. 3 shows various materials for use as a first insulation layer in a perspective view,

[0027] Fig. 4 shows the electrical power line in a perspective view in a second embodiment,

[0028] Fig. 5 shows a plurality of different embodiments of a conductor,

[0029] Fig. 6 is a schematic view of a battery module,

[0030] Fig. 7 is a schematic view of a power electronics system.

[0031] The figures are merely schematic and serve solely to facilitate understanding of the invention. The same elements are provided with the same reference numerals. Features of the individual embodiments can be interchanged and used alternatively / cumulatively.

[0032] Fig. 1 shows an electrical power line 1 according to the invention for connecting electrical components in a motor vehicle, preferably for connecting battery elements 2 of a battery module 3, with a conductor 4, a first insulation layer 5, comprising a fabric tape 6a (see Fig. 3a), a film 6b (see Fig. 3b) or a paper 6c (see Fig. 3c), wherein the fabric tape 6a, the film 6b or the paper 6c is wound around the conductor 4, and a second insulation layer 7, which is applied as a powder layer to completely enclose the first insulation layer 5 on this first insulation layer 5.

[0033] Fig. 1 shows an electrical power line 1 according to the invention in a sectional view. The conductor 4 has a rectangular cross-section. The fabric tape 6 in the form of the first insulation layer 5 lies against an outer side 8 of the conductor 4. The second insulation layer 7 in the form of the powder layer lies against an outer side 9 of the fabric tape 6. Fig. 2 shows a second embodiment of the electrical power line 1 according to the invention in a perspective view. The conductor 4 is shown here in the form of a sheet metal bent several times in different directions. The conductor 4 is divided into different sections 10, 11, 12. The conductor 4 has a start section 10, a middle section 11 and an end section 12, with a first transition section 13 being formed between the start section 10 and the middle section 11 and a second transition section 14 being formed between the middle section 11 and the end section 12.

[0034] The initial section 10 and the end section 12 each have a through-opening 15 in the form of a circular hole. The middle section 11 has a total of two through-openings 15 in the form of a circular hole. The through-openings 15 serve to connect individual battery elements 2 (not shown here).

[0035] The transition sections 13, 14 are covered by the first insulation layer 5 and the second insulation layer 7, with the first insulation layer 5 being concealed as shown. Furthermore, the transition sections 13, 14 are angularly deformed.

[0036] Figures 3a to 3c show various materials intended for use as the first insulation layer 5. Figure 3a shows a fabric tape 6a wound on a roll, Figure 3b shows an (insulating) foil 6b wound on a roll, and Figure 3c shows an (insulating) paper 6c wound on a roll.

[0037] Fig. 3a shows a perspective view of the fabric tape 6a. In the view shown, the fabric tape 6a is depicted in a rolled-up state, with a starting piece 16 of the fabric tape 6a being unrolled. The fabric tape 6a has a fiber structure 17 typical of a fabric and has a one-sided adhesive layer 26. Fig. 3b shows a perspective view of the film 6b. In the view shown, the film 6b is depicted in a rolled-up state, with a starting piece 16 of the film 6b being unrolled. The film 6b has a one-sided adhesive layer 26.

[0038] In Fig. 3c, the paper 6c is shown in a perspective view. The paper 6c is depicted in a rolled-up state. The paper 6c has a one-sided adhesive layer 26, which is, however, concealed by the rolled-up state.

[0039] Fig. 4 shows a further, second embodiment of the electrical power line 1 according to the invention in a perspective view. In the present embodiment, the conductor 4 has a rectangular cross-section, wherein the conductor 4 has a straight extension in the longitudinal direction 18. The conductor 4 has two sections, the starting section 10 and the end section 12, wherein the starting section 10 is formed on a first end side in the longitudinal direction 18 and the end section 12 is formed on a second end side, the other side. The two sections 10, 12 are free of the two insulation layers 5, 7. In the present embodiment, the first insulation layer 5 is encased and covered by the second insulation layer 7.

[0040] In Figs. 5a to 5d different embodiments of the conductor 4 are shown.

[0041] In Fig. 5a, the conductor 4 is shown in the form of a sheet, in a first embodiment. The conductor 4 is divided in the longitudinal direction 18 into three sections: a starting section 10, a middle section 11, and an end section 12. The starting section 10 and the end section 12 are connected to one another by means of the middle section 11. According to the longitudinal direction 18 of the conductor 4, the starting section 10 and the end section 12 extend in the horizontal direction. The middle section 11 extends in the vertical direction. In the longitudinal direction 18, in the transition between the starting section 10 and the middle section 11, a first kink / bend 19 is formed, whereby an angle of 90° is formed between the starting section 10 and the middle section 11.In the longitudinal direction 18, at the transition between the central section 11 and the end section 12, a second kink / bend 20 is formed, creating an angle of 90° between the central section 11 and the end section 12. A radius is formed at the respective bends 19, 20. The conductor 4 is thus bent in a stepped manner in the longitudinal direction 18, with a step in the 90° direction.

[0042] In Fig. 5b, the conductor 4 is shown in a form comparable to Fig. 5a, in a second embodiment. Compared to Fig. 5a, the extension of the central section 11 is much smaller than the extension in the longitudinal direction 18 of the initial section 10 and the end section 12. The angle formed between the initial section 10 and the central section 11, as well as between the central section 11 and the end section 12, is 45° in this case. Thus, the central section 11 has an S-shaped cross-section.

[0043] Fig. 5c shows a third embodiment of conductor 4. In this case, conductor 4 is wire-shaped. Here, conductor 4 is bent at an angle, in this case 90°. The conductor has a radius at the bending point.

[0044] Fig. 5d shows a fourth embodiment of the conductor 4. In this case, the conductor 4 is formed from a plurality of individual wires 21 extending in the longitudinal direction 18 and twisted together in the circumferential direction 22.

[0045] Fig. 6 shows a schematic view of a battery module 3 with individual battery elements 2, in this case two battery elements 2. The battery elements 2 are arranged in a housing 23. Adjacent battery elements 2 are connected to one another by means of the electrical power line 1. The battery elements 2 each have at least one connection pin 24, to which the electrical power line 1 is respectively fixed in order to establish an electrical connection between the two battery elements 2. The electrical power line 1 is connected to one battery element 2 via the through-opening 15 at the start section 10 and to the other battery element 2 via the opening 15 at the end section 12. In the longitudinal direction 18 between the two through-openings, the two insulation layers 5, 7 are formed on the conductor 4, the first insulation layer 5 being concealed.

[0046] Fig. 7 shows a schematic view of a power electronics unit 25. The power electronics unit 25 is connected to a battery module via the electrical power line 1.

[0047] 3. In principle, it is also possible to electrically connect electrical components installed in the power electronics using the electrical power line 1.

[0048] List of reference symbols electrical power line battery element battery module

[0049] Conductor first insulation layer a fabric tape b foil c paper second insulation layer

[0050] outside

[0051] Outside 0 Initial section 1 Middle section 2 End section 3 First transition section 4 Second transition section 5 Through opening 6 Initial section 7 Fibre 8 Longitudinal direction 9 First bend 0 Second bend 1 Wire 2 Circumferential direction 3 Housing 4 Connection pin 5 Power electronics 6 Adhesive layer

Claims

Patent claims 1. Electrical power line (1) for connecting electrical components in a motor vehicle, preferably for connecting battery elements (2) of a battery module (3), with a conductor (4), a first insulation layer (5) comprising a fabric tape (6a), a film (6b) or a paper (6c), wherein the fabric tape (6a), the film (6b) or the paper (6c) is wound around the conductor (4), and a second insulation layer (7) which is applied to this first insulation layer (5) as a powder layer for completely encasing the first insulation layer (5).

2. Electrical power line (1) according to claim 1, characterized in that the powder layer is a resin layer formed from an epoxy resin.

3. Electrical power line (1) according to claim 1 or 2, characterized in that the electrical power line (1) is a busbar.

4. Electric power line (1) according to one of claims 1 to 3, characterized in that the fabric tape (6a) is an adhesive tape, the film (6b) is an adhesive film or the paper (6c) is an adhesive paper and adheres self-adhesively to an outer side (8) of the conductor (4).

5. Electric power cable (1) according to claim 4, characterized in that the fabric tape (6a) is wound in turns over the outer side (8) of the conductor (4).

6. Electric power line (1) according to claim 5, characterized in that the windings at least partially overlap when following a longitudinal axis 7. Electrical power line (1) according to one of the preceding claims, characterized in that the fabric band (6a) is formed from glass fiber.

8. Battery module (3) for a motor vehicle, comprising at least two battery elements (2) which are electrically connected to one another via an electrical power line (1) according to one of the preceding claims.

9. Power electronics (25) for a motor vehicle, wherein the power electronics (25) is electrically connected to a battery module (3) according to claim 9 by means of an electrical power line (1) according to one of claims 1 to 8 or electrical components in the power electronics (25) are electrically connected to one another by means of an electrical power line (1) according to one of claims 1 to 8.

10. Method for producing an electrical power line (1), in which in a first step a conductor (4), preferably made of copper, is formed, in a second step the conductor (4) is wrapped by a first insulation layer (5), comprising a fabric tape (6a), a film (6b) or a paper (6c), and in a third step the first insulation layer (5) is encased by a second insulation layer (7) in the form of a powder coating.

Images