Electrical power line having a multilayer tube; 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), wherein the conductor (4) is surrounded by a multi-layer tube (5), and the tube (5) is designed as a shrink tube. The invention also relates to a battery module (3), power electronics (24) and a method for producing an electrical power line (1).

Description

[0001] Electrical power cable with a multilayer hose; battery module; power electronics

[0002] 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.

[0003] 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's 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.

[0004] The object of the present invention is to provide an electrical power line which is particularly stable and has a high level of durability.

[0005] This is achieved in an existing electrical power line in that the electrical power line is designed with a conductor, wherein the conductor is surrounded by a multi-layer tube, wherein the tube is designed as a heat-shrink tube. Using a multi-layer tube, several insulation layers can be formed, and this can be implemented using a prefabricated component / element. This simplifies production, as the tube has several layers and is less susceptible to faulty sheathing of the conductor. The tube preferably comprises a material that is shrinkable above a predetermined temperature so that the tube can adhere to the conductor.

[0006] Advantageous embodiments are claimed in the subclaims and are explained in more detail below. It is advantageous if a first insulation layer of the hose is formed from fabric, an insulation film or an insulation paper. This provides a flexible first insulation layer which can be applied to the conductor. The fabric, film or paper is preferably made of a temperature-resistant material in order to withstand, for example, very high temperatures. This can be helpful in preventing a short circuit in the event of fires in a motor vehicle in which the electrical power line for connecting two battery elements is installed. The fabric preferably has fibers which extend in the longitudinal direction and are distributed in the circumferential direction and are in the form of interconnected individual fibers.Particularly preferably, the fiber pattern has a wave-like extension in the longitudinal direction. In other words, the individual fibers are formed in a jagged shape in the longitudinal direction. This pattern allows for a kink-free fit against the outer surface of the conductor during shrinking. During shrinking, the fabric can contract more effectively, thus reducing the cross-section of the shrink tubing. This makes the formation of the insulation layers on the conductor less prone to errors.

[0007] Furthermore, a second insulation layer of the hose can be made of a thermoplastic. The thermoplastic allows for shrinking the hose. Depending on the type of thermoplastic selected, various temperature windows can be selected for shrinking the hose. This allows for a particularly flexible design of the electrical power line. Alternatively, the second insulation layer of the hose can be made of a thermoset or an elastomer.

[0008] It is advisable for the first insulation layer to be directly adjacent to or encase an outer surface of the conductor. This ensures that the first insulation layer adheres fully to the conductor.

[0009] It is advantageous if the second insulation layer is directly adjacent to the first insulation layer or encases the first insulation layer. This allows the first insulation layer to be completely surrounded by the second insulation layer. This ensures complete insulation of the first insulation layer, thus protecting it from external influences.

[0010] According to the design with two insulation layers, the first insulation layer is encased in the second insulation layer, thus protecting the first insulation layer. This creates a highly insulated electrical line that can withstand various influences. The electrical line is designed so 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.

[0011] Furthermore, the electrical power line can be a busbar. The conductor is preferably formed from a sheet metal, preferably copper. Using a sheet metal, various cross-sectional shapes or contours can be implemented, which are preferred for the specific application of the busbar. Particularly preferably, the 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] 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.

[0014] The invention also relates to a battery module for a motor vehicle, comprising at least two battery elements that are electrically connected to one another via a previously described electrical power line. 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 an electrical power line.

[0015] The invention also relates to a method for producing an electrical power cable, in particular a busbar, in which a conductor, preferably made of copper, is formed in a first step, a multi-layer hose, preferably with a first insulation layer made of fabric, an insulation film or an insulation paper, the fabric preferably being made of glass fiber, and a second insulation layer made of a thermoplastic, a thermoset or an elastomer, is guided around the conductor and in a third step the hose is shrunk under the influence of temperature so that the hose rests against an outer side of the conductor. 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.In other words, fiberglass has a very high heat resistance, which means it can 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] In other words, the invention describes a busbar with insulation by means of a heat-shrink tubing made of a thermoplastic, a thermoset, or an elastomer and a fiberglass fabric. The insulation comprises a thermoplastic, a thermoset, or an elastomer as a heat-shrink tubing, which contains a fiberglass fabric. The busbar is preferably formed from copper.

[0017] The invention also relates to a method for producing a busbar, preferably made of copper, in which the copper busbar is formed / machined in a first step. In a second step, the shrink tube containing fiberglass fabric, (insulating) foil, or (insulating) paper is guided around the copper busbar. In a third step, the shrink tube is shrunk at high temperature. Various advantageous embodiments of the invention are explained in more detail below with reference to a drawing with figures.

[0018] They show:

[0019] Fig. 1 shows two electrical power lines according to the invention in a sectional view,

[0020] Fig. 2 a variety of different hoses in a perspective view,

[0021] Fig. 3 shows the electrical power line in a perspective view in a first embodiment,

[0022] Fig. 4 shows the electrical power line in a perspective view in a further embodiment,

[0023] Fig. 5 shows a plurality of different embodiments of a conductor,

[0024] Fig. 6 is a schematic view of a battery module,

[0025] Fig. 7 is a schematic view of a power electronics system.

[0026] 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.

[0027] 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, wherein the conductor 4 is surrounded by a multi-layer hose 5, wherein the hose 5 is designed as a shrink hose. Fig. 1 shows an electrical power line 1 according to the invention in a sectional view. In Fig. 1a a cross-section of the electrical power line 1 is rectangular and in Fig. 1b the cross-section is circular. A first insulation layer 7 of the hose 5 lies against an outer side 6 of the conductor 4. A second insulation layer 9 of the hose 5 lies against an outer side 8 of the first insulation layer 7.

[0028] Fig. 2 shows a plurality of double-shell / two-layer hoses 5 with different cross-sectional sizes that can be used in the electrical power line 1 according to the invention. The hose 5 has two insulation layers 7, 9, the first insulation layer 7 in the form of a woven fabric, in this case a glass fiber fabric, and the second insulation layer 9. The hose 5 has the first insulation layer 7 radially on the inside and the second insulation layer 9 radially on the outside, adjacent to the first insulation layer 7. The fabric has fibers 12 in the form of interconnected individual fibers that extend in the longitudinal direction 10 and are distributed in the circumferential direction 11. The fibers 12 have a pattern, wherein the individual fibers have a wavy / jagged extension in the longitudinal direction 10.

[0029] Fig. 3 shows an embodiment of the electrical power cable 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 various sections 13, 14, 15. The conductor 4 has a starting section 13, a middle section 14, and an end section 15. A first transition section 16 is formed between the starting section 13 and the middle section 14, and a second transition section 17 is formed between the middle section 14 and the end section 15.

[0030] The initial section 13 and the end section 15 each have a through-opening 18 in the form of a circular hole. The middle section 14 has a total of two through-openings 18 in the form of a circular hole. The through-openings 18 serve to connect individual battery elements 2 (not shown here). The transition sections 16, 17 are coated with the first insulation layer 7 and the second insulation layer 9 according to the design of the hose 5, with the first insulation layer 7 being concealed as shown. Furthermore, the transition sections 16, 17 are angularly deformed.

[0031] Fig. 4 shows a further embodiment of the electrical power cable 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 10. The conductor 4 has two sections, the starting section 13 and the end section 15, wherein the starting section 13 is formed on a first end side in the longitudinal direction 10 and the end section 15 is formed on a second end side, the other side. The two sections 13, 15 are free of the two insulation layers 7, 9. In the present embodiment, the first insulation layer 7 is surrounded and covered by the second insulation layer 9.

[0032] In Figs. 5a to 5d different embodiments of the conductor 4 are shown.

[0033] Fig. 5a shows a first embodiment of the conductor 4 in the form of a sheet metal. The conductor 4 is divided in the longitudinal direction 10 into three sections: a starting section 13, a middle section 14, and an end section 15. The starting section 13 and the end section 15 are connected to one another by means of the middle section 14. According to the longitudinal direction 10 of the conductor 4, the starting section 13 and the end section 15 extend horizontally. The middle section 14 extends vertically. In the longitudinal direction 10, in the transition between the starting section 13 and the middle section 14, a first kink / bend 19 is formed, creating an angle of 90° between the starting section 13 and the middle section 14.In the longitudinal direction 10, at the transition between the central section 14 and the end section 15, a second kink / bend 20 is formed, creating an angle of 90° between the central section 14 and the end section 15. A radius is formed at the respective bends 19, 20. The conductor 4 is thus bent in a stepped manner in the longitudinal direction 10, with a step in the 90° direction.

[0034] 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 14 is much smaller than the extension in the longitudinal direction 10 of the initial section 13 and the end section 15. The angle formed between the initial section 13 and the central section 14, as well as between the central section 14 and the end section 15, is 45° in this case. Thus, the central section 14 has an S-shaped cross-section.

[0035] 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.

[0036] 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 10 and twisted together in the circumferential direction 11.

[0037] 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 22. 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 23, 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 18 at the start section 13 and to the other battery element 2 via the opening 18 at the end section 15. In the longitudinal direction 10 between the two through-openings 18, the two insulation layers 7, 9 are formed on the conductor 4, the first insulation layer 7 being concealed.

[0038] Fig. 7 shows a schematic view of a power electronics system 24. The power electronics system 24 is connected to a battery module 3 via the electrical power line 1. In principle, it is also possible to electrically connect electrical components installed in the power electronics system 24 to one another via the electrical power line 1.

[0039] List of reference symbols electrical current line battery element battery module conductor hose outside first insulation layer outside second insulation layer longitudinal direction circumferential direction graining initial section middle section end section first transition section second transition section through-hole first bend second bend wire housing connection pin power electronics

Claims

Patent claims 1. Electrical power cable (1) for connecting electrical components in a motor vehicle, preferably for connecting battery elements (2) of a battery module (3), to a conductor (4), wherein the conductor (4) is surrounded by a multi-layer hose (5), wherein the hose (5) is designed as a shrink hose.

2. Electrical power line (1) according to claim 1, characterized in that a first insulation layer (7) of the hose (5) is formed from a fabric, a film or a paper.

3. Electrical power line (1) according to claim 1 or 2, characterized in that a second insulation layer (9) of the hose (5) is formed from a thermoplastic, a thermosetting plastic or an elastomer.

4. Electrical power line (1) according to claim 2 or 3, characterized in that the first insulation layer (7) lies directly against an outer side (6) of the conductor (4).

5. Electrical power line (1) according to claim 3 or 4, characterized in that the second insulation layer (9) lies directly against an outer side (8) of the first insulation layer (7).

6. Electrical power line (1) according to one of claims 2 to 5, characterized in that the fabric is made of glass fiber.

7. Electrical power line (1) according to one of the preceding claims, characterized in that a cross section of the electrical conductor (4) is rectangular.

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 (24) for a motor vehicle, wherein the power electronics (24) is electrically connected to a battery module (3) according to claim 8 by means of an electrical power line (1) according to one of claims 1 to 7 or electrical components in the power electronics (24) 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 a multi-layer hose (5) is guided around the conductor (4) and in a third step the hose (5) is shrunk under the influence of temperature so that the hose (5) rests on an outer side (6) of the conductor (4).

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