Insulator for busbar

Abstract

The invention relates to a busbar insulator 10 for insulating a busbar 12, wherein the busbar insulator 10 comprises a composite material. The composite material includes a polymeric matrix material and a fibrous material disposed in the matrix material. The polymer matrix comprises a thermoplastic polymer component. The fibrous material is based on one or more non-combustible inorganic components. The invention also relates to the use of a busbar insulator for insulating a busbar, a busbar provided with a busbar insulator, and an energy system comprising a busbar.

Description

TECHNICAL FIELD

[0001] The present invention relates to a busbar insulation. The present invention also relates to a busbar having such an insulation. Furthermore, the present invention relates to an energy storage system comprising at least one such busbar. BACKGROUND

[0002] In electrically driven vehicles, such as in purely electrically driven vehicles, hybrid vehicles or plug-in vehicles, there is usually a high current. In particular, a high current flows between a high-voltage battery and an electric motor of an electric vehicle. For this purpose, a busbar is usually provided which is able to conduct a high current. The busbar must be correspondingly safely insulated. The insulating material used must ensure that the surrounding components are shielded from the high voltage or high current flowing through the busbar. Furthermore, the insulating properties must also be ensured for fault situations in which a high thermal load can occur.

[0003] CN 204190113 U describes an insulation foil for a busbar which is intended to increase the creepage distance between the copper pillars. Typically, an insulation foil, copper pillars and a busbar are provided. The insulation foil comprises an edge seal and the busbar comprises a grommet. The insulation foil is arranged on the busbar surface around the copper pillars.

[0004] CN 211670261 U describes a busbar insulation structure comprising a busbar comprising a plurality of busbar bodies, a first flame-retardant insulation film on which the busbar is mounted, and a second flame-retardant insulation film connected with the first flame-retardant insulation film so that the busbar is sandwiched between the first and second flame-retardant insulation films.

[0005] CN 213844898 U discloses a busbar insulation device comprising an upper protection plate and a lower protection plate, wherein one side or both sides of the upper protection plate and the lower protection plate are provided with an insulation fixing edge, the middle part of the upper protection plate and the middle part of the lower protection plate are provided with an insulation seal, the insulation fixing edge is provided with an insulation magnet, and the upper protection plate and the lower protection plate are connected with the insulation magnet through a positioning device.

[0006] CN 109215895 A describes a method for insulating a busbar. This method comprises coating a straight section of the busbar with an insulation film, such as a PET polyester film, sealing the structure thus produced, applying a sealing substance and drying the busbar.

[0007] CN 105957591 A describes an insulation coating for irregular busbars. For this purpose, an insulation made of a polyurethane film is used.

[0008] US 2019 / 237956 A1 describes an arrangement for electrically connecting at least one electrical component to a first busbar and a second busbar, which have different electrical potentials relative to each other during electrical operation.

[0009] US 2020 / 0335238 A1 describes a thermally conductive, electrically insulating nonwoven material, in particular for improved heat dissipation from electrical transformers, electric motors, and generators. The material comprises, inter alia, organic fibers and a polymer matrix.

[0010] EP 2372723 A1 relates to the curing of electrical insulators and, in particular, to improving the curing of electrical insulators. The method comprises impregnating fibers with a UV-curable matrix.

[0011] RU 2501109 C2 relates to an insulated composite power cable having a core defining a common longitudinal axis, a plurality of composite wires surrounding the core, and an insulating jacket surrounding the composite wires. The composite wires can comprise, inter alia, an epoxy resin matrix and aramid fibers.

[0012] EP 3259762 B1 relates to an insulating element for electrical insulation in the high-voltage range having a low electrical conductivity, which comprises natural fiber materials, preferably from wood and / or annual plants.

[0013] However, the solutions according to the prior art still show potential for improvement. SUMMARY

[0014] It is an object of the present invention to at least partially overcome at least one of the drawbacks of the prior art. In particular, it is an object of the present invention to provide a reliable insulator for a busbar, which can provide a safe insulation even under high thermal loads. The inventors have surprisingly found that the present invention can advantageously provide a reliable insulator for a busbar, which can provide an electrical insulation, and / or which can provide an improved protection against discharge events during and even after a thermal runaway event.

[0015] This object is at least partially solved by a busbar insulator having features as disclosed herein. The object is further solved by a use having features as disclosed herein, by a busbar having features as disclosed herein, and by an energy storage system having features as disclosed herein. Preferred embodiments of the present invention are described in the dependent claims, the description or the drawings, wherein further features described or shown in the dependent claims or the description or the drawings can constitute the object of the present invention, alone or in any combination, unless clearly contradicted by a context.

[0016] This describes a bus insulator for insulating a busbar, the bus insulator comprising at least a composite material comprising a polymer matrix material and a fibrous material disposed within the matrix material. Preferably, the fibrous material comprises a composition selected to at least temporarily withstand thermal oxidation conditions during the period, or is substantially composed of a composition selected to at least temporarily withstand thermal oxidation conditions during the period. As described in more detail below, the polymer matrix material is preferably, but not necessarily, based on a thermoplastic component. Alternatively, the matrix material may consist at least partially or substantially of a thermosetting plastic component.

[0017] This busbar insulator has significant advantages over existing technology solutions.

[0018] Therefore, the described bus insulator is suitable for electrically insulating the bus and can be conveniently mounted on or coated onto the bus for this purpose. A bus should be understood in particular as including components of this type that connect individual energy storage devices (e.g., battery cells or battery packs) to each other in an energy storage system, or that connect energy storage devices to, for example, an electric motor in an energy storage system. In principle, such buses are typically made of metals (such as aluminum or copper). This achieves good connectivity. Therefore, the bus must be electrically insulated. This insulator must ensure that surrounding parts are shielded from the high voltage or high current flowing through the bus.

[0019] Especially in mobile applications, such as those in electric vehicles (e.g. motor vehicles), it is even more important that the insulation properties of the bus insulator are maintained for at least a certain period of time, even in emergency situations such as car crashes, battery failures, or fires, such as thermal oxidation conditions, such as conditions during thermal runaway.

[0020] To achieve this, the bus insulator described herein is provided to comprise a composite material, for example, consisting of a polymer matrix material and a fibrous material disposed within the matrix material. The arrangement of the fibrous material within the matrix material is, in principle, freely selectable depending on the specific application. Preferably, the fibrous material can be in the form of a textile, such as a woven fabric, nonwoven fabric, tape, or scrim. This allows the fibrous material to have a defined arrangement or three-dimensional structure, ensuring or at least improving good insulation even under fault conditions.

[0021] Typically, fibrous materials are based on one or more non-flammable inorganic components, primarily comprise one or more non-flammable inorganic components, or even consist essentially of one or more non-flammable inorganic components, preferably one or more inorganic components disclosed herein. As used herein, the phrase "fibrous material consisting essentially of one or more inorganic components" can be understood to mean a fibrous material containing no more than 10 wt%, preferably less, for example, less than 5 wt% or even less than 1 wt% of a flammable component. Not wishing to be bound by theory, the inventors have found that the higher the fraction of flammable / combustible components contained in the fibrous material, the worse the stability of the insulator during the progression of thermal oxidative degradation of the polymer matrix and / or after a fire / thermal runaway event.

[0022] Therefore, in the case of the bus insulator described herein, it can retain its insulating properties at least for a limited period of time, even after an unexpected event (such as an accident or fire). This is especially true in situations such as a fire occurring in a vehicle after an accident (which poses a potential hazard to the insulating material), or in the event of battery failure or a similar event (such as thermal runaway). The bus insulation according to the invention also prevents the loss of insulating capacity, or in particular dielectric strength, due to exposure to high temperatures in the event of a fire, and prevents further exacerbation of hazards arising from energy storage systems.

[0023] According to the present invention, at least for a certain period of time, it is possible to prevent, for example, vehicle occupants from being directly exposed to significant danger due to busbar insulator failure.

[0024] In this respect, the solution according to the invention is particularly easy to implement because the insulator is very simple in structure and consists mainly or essentially of fibers and matrix materials.

[0025] Furthermore, it enables particularly simple adaptations to desired specific applications. By altering the structure of the bus insulator or its insulating material, for example by changing the number, thickness, and design of the fiber structure and the fiber material within the insulating material, the insulation capability, namely, in particular the dielectric strength (also known as electrical breakdown resistance) or breakdown voltage, can be tuned in a desired manner.

[0026] Using suitable fiber materials offers the following advantages: It eliminates the need for excessively stringent requirements on the plastic matrix material. Even if the matrix material loses at least some of its insulating properties after a short period, the fiber material can retain the insulating properties of the insulating material after prolonged exposure to high temperatures. This generally makes it more resilient to conditions that may occur during a fire than when using plastic as the matrix material.

[0027] Therefore, for the purpose of solving the resistance of insulation behavior (i.e., in particular breakdown voltage), it is particularly preferred to be based at least in part on the properties of the fiber or the fiber structure.

[0028] Particularly preferably, the insulation properties of the bus insulator (i.e., particularly the electrical breakdown voltage) can be maintained at a value of at least 700 V DC for at least 5 minutes, or for at least 10 minutes, at a temperature of at least 450°C, for example at least 500°C, or for example at least 1000°C. The breakdown voltage can be determined according to DIN EN 60243.

[0029] In principle, it is advantageous if the fibers are formed of an electrically insulating material (preferably an electrically insulating and non-flammable material). It is further preferred if the fiber length of the fiber material is in the range of ≥10 mm. In this embodiment, the fibers may preferably comprise so-called continuous fibers. Continuous fibers (also called long fibers) are known in the art and should be understood herein as having an aspect ratio of at least 500. For example, the length of long fibers in an insulator can extend along the transverse dimension of the busbar insulator in which they reside. In particular, in this embodiment, the fibers can be allowed to maintain a stable fiber structure, which can also be used as an insulating material in extreme cases without a matrix material, even in the event of insulation material damage or, in principle, thermal effects. Especially according to this embodiment, particularly reliable insulation capability can be ensured even under prolonged exposure to high temperatures, even if the matrix material cannot withstand these conditions.

[0030] Furthermore, especially when using such fibers, it is preferable to provide the fibers as textiles, such as woven fabrics, nonwoven fabrics, tapes or loose fabrics or laid-up fabrics, which can further enhance the aforementioned properties. In this way, a precisely defined three-dimensional structure is provided that surrounds the busbar and thus can provide sufficient insulation together with the matrix material or the air present.

[0031] The matrix material may comprise thermosetting or thermoplastic plastic components. In particular, such plastics can possess good insulating properties and are easily processed, making the insulating material according to the invention advantageously suitable for use as an insulator for busbars. Particularly preferred is that the plastic of the matrix material can be a thermoplastic. Compared to thermosetting-based matrix materials, thermoplastics advantageously offer one or more of the following: relatively easy application onto and / or around the busbar; and recyclability.

[0032] Insulating composite materials can typically be identified as having a strength higher than 10. 12 Resistivity (ohms * mm²) / m. Higher resistivity results in better electrical insulation properties per unit thickness of busbar insulator. Fibers used in composite materials preferably have higher resistivity. Preferably, it is above 10. 15 -10 21 Within the range of (ohms * mm²) / m, for example, 1016 -10 20 (Ohms*mm²) / m, such as glass fiber. Other fiber materials in this range include other mineral fibers, such as ceramic fibers and / or basalt fibers.

[0033] Regarding the multilayer structure, it may be advantageous for the composite material (i.e., the actual insulating material of the bus insulator) to have at least one core layer with fibrous material, which is surrounded by end layers (surface layers) with non-fibrous matrix material. Thus, a multilayer structure is provided that includes a core layer having fibrous material disposed within and, for example, in complete contact with the matrix material. Along the multilayer structure, this is preferably surrounded on both sides by pure (i.e., non-fibrous) matrix material of the end layers, thereby forming a sandwich structure. In this way, the described insulating properties can be combined in a particularly preferred manner with suitability as an insulator, especially processability for this purpose. However, in principle, multilayer structures are also possible, in which there is more than one core layer with optional pure matrix material layers in between.

[0034] Regarding the matrix material, and particularly in order to combine good processability with good insulation properties, the preferred matrix material comprises a thermoplastic polymer selected from the group consisting of: polyamides (especially polyamide 6 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), polyamide 11 (PA11)), polyolefins (especially polyethylene (PE), polypropylene (PP)), polyphenylene sulfide (PPS), thermoplastic polyurethane (TPU), polyphthalamide (PPA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (PEI), polyetheretherketone (PEEK), polystyrene (PS), styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene copolymer (ABS), polysulfone (PSU), and polylactic acid (PLA). For thermosetting materials, epoxy resins may be used, for example.

[0035] Regarding fibrous materials (i.e., materials from which fibers are made), it is preferable that the fibrous materials be selected from a list consisting of glass, aramid, basalt, natural fibers, or mixtures thereof. Such fibers have good electrical insulation properties and can generally be easily processed in the form of woven fabrics, nonwoven fabrics, tapes, loose fabrics, or laminated fabrics (such as multi-layered fabric sheets).

[0036] Regarding the combined benefits of electrical insulation properties, ease of processing, and mitigation of discharge, one or more of the following are particularly preferred: mineral fibers, including ceramic fibers, glass-based fibers, and / or basalt-based fibers; or combinations thereof. Glass and basalt have proven to be exemplary suitable non-combustible materials that can exhibit good electrical insulation properties during normal operation and mitigate the loss or reduction of protection against discharge during thermal oxidizing conditions, such as thermal runaway. In a preferred embodiment, the fiber material may comprise continuous fiber textiles (i.e., fibers ≥10 mm in length), such as woven fabrics, nonwoven fabrics, tapes, or loose fabrics based on at least one raw material selected from the list of glass, aramids, basalt, natural fibers, or mixtures thereof, and the matrix material may comprise thermoplastics selected from the list of: polyamides (particularly polyamide 6 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), polyamide 11 (PA11)), polyolefins ( In particular, polyethylene (PE), polypropylene (PP), polyphenylene sulfide (PPS), thermoplastic polyurethane (TPU), polyphthalamide (PPA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (PEI), polyetheretherketone (PEEK), polystyrene (PS), styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene copolymer (ABS), polysulfone (PSU), and polylactic acid (PLA). Based on the above description, continuous fiber textiles are preferably based on one or more raw materials selected from the list consisting of glass and basalt.

[0037] Regarding the fiber proportion, what may be particularly advantageous for the properties described is that the fiber material is present in the insulating material at a proportion of ≥30 vol% to ≤90 vol%, referring to the entire composite material. Preferably, the fiber proportion can be in the range of ≥40 vol% to ≤50 vol%, such as ≥43 vol% to ≤48 vol%. This fiber volume fraction allows for an advantageous combination of good dielectric strength that remains after prolonged exposure to heat with good machinability.

[0038] It is understood that the bus insulator disclosed herein can advantageously be manufactured as, for example, a structural element independent of the bus. The disclosed bus insulator can be, for example, in the form of a planar sheet material. The bus insulator can advantageously be applied to the insulating bus in a separate application step. For example, the application process includes one or more of the following: adjusting the dimensions of the material to match the dimensions of the bus or a portion thereof to be insulated, and applying the insulating product onto the bus or a portion thereof. The dimensional adjustment and sequential application can advantageously be performed using conventional processes known in the art, including but not limited to cutting and sequential thermoforming.

[0039] Other advantages and technical features of bus insulators are described herein with reference to the descriptions of applications, busbars, energy storage systems, figures and descriptions thereof, and vice versa.

[0040] The use of bus insulators for insulating busbars is also described, wherein the bus insulators are formed as described above.

[0041] It has been demonstrated that the described insulator or its insulating material has very good properties, particularly for insulating busbars. Specific applications include busbar insulation in capacity storage systems, especially in mobile applications such as motor vehicles.

[0042] In particular, good processability can be combined with high electrical insulation quality. Specifically, the insulation quality is maintained even after prolonged exposure to high temperatures. Therefore, according to the invention, insulation properties can be maintained after a heat load of at least 450°C for at least 5 minutes, and the insulation properties are quantified by electrical breakdown voltage and have a value of at least 700 V DC, specifically measured according to DIN EN 60243.

[0043] This allows for improved safety performance even in the event of malfunctions (such as accidents) and associated heat generation (such as fires).

[0044] Other advantages and technical features of the application are described herein with reference to the description of busbar insulators, busbars, energy storage systems, figures and descriptions of figures, and vice versa.

[0045] A bus for connecting an energy storage device to another energy storage device or an electric motor is also described, the bus being provided with a bus insulator for electrically insulating the bus. The bus insulator is designed as described above.

[0046] In particular, busbars can be part of an energy storage system and can be used in mobile applications such as motor vehicles.

[0047] This type of bus provides the advantages described above in particular. In summary, it also improves safety performance in the event of malfunctions (such as accidents) and associated heat generation (such as fires).

[0048] Such a busbar with a busbar insulator can be produced, for example, by placing the busbar in a molding die and coating the busbar insulator with busbar insulating material by molding the insulating material, thereby applying the insulating material to the busbar and manufacturing the busbar insulator.

[0049] Other advantages and technical features of the busbar are described herein with reference to the descriptions of its applications, busbar insulators, energy storage systems, figures, and figure descriptions, and vice versa.

[0050] An energy storage system is also described, comprising at least one energy storage device for supplying electrical energy to an electric motor, and the energy storage system includes at least one bus for electrically connecting the energy storage device to another energy storage device or to the electric motor. The bus is designed as described above.

[0051] In particular, the energy storage device can be part of an energy storage system and can be used in mobile applications such as motor vehicles.

[0052] The aforementioned advantages are particularly relevant to energy storage systems. In summary, safety performance can also be improved in the event of malfunctions (such as accidents) and associated heat generation (such as fires).

[0053] Other advantages and technical features of the energy storage system are described herein with reference to the description of its uses, bus insulators, busbars, figures, and figure descriptions, and vice versa.

[0054] The present invention will be explained by way of example below with reference to the accompanying drawings and embodiments, wherein the features set forth below may each constitute aspects of the present invention individually or in combination, and wherein the present invention is not limited to the following drawings, description and embodiments. Attached Figure Description

[0055] As shown below:

[0056] Figure 1 A schematic diagram of a busbar coated with insulating material is shown; and

[0057] Figure 2 It shows along Figure 1 The view of the insulating material defined in view AA. Detailed Implementation

[0058] Figure 1 A busbar 12 insulated with insulating material 14 is shown. Therefore, the insulating material 14 forms a busbar insulator 10 on the busbar 12. This busbar 12 can, for example, be part of an energy storage system, where it is used to connect an energy storage device to another energy storage device or to an electric motor. One or more energy storage devices are then used to supply electrical energy to the electric motor.

[0059] Figure 2 The text shows the data based on... Figure 1 The view shown is a cross section passing through the insulating material 14 or through the busbar insulator 10.

[0060] The insulating material 14 comprises a composite material including a polymer matrix material and a fibrous material disposed within the matrix material, such that the bus insulator 10 preferably has an electrical breakdown voltage or dielectric strength of at least 700 V DC, and wherein the insulating material 14 is molded such that the breakdown voltage or dielectric strength of the bus insulator 10 remains even after a heat load of at least 450°C for at least 5 minutes. Figure 2 As shown, the composite material has at least one core layer 16 comprising fibrous material, the core layer 16 being surrounded by end layers 18, 20 comprising non-fibrous matrix material.

[0061] This layered structure can have a thickness ranging from ≥0.2 mm to ≤5 mm, for example, from ≥0.9 mm to ≤3 mm, such as from ≥1.2 mm to ≤2 mm. Each layer or single layer (plies, sheets, laminates) can have its own corresponding thickness.

[0062] Typically, and regardless of the specific implementation method, multiple layers may be provided. For example, multiple core layers 16 may be provided, each core layer being separated by a fiber-free layer of matrix material, and the core layer 16 is surrounded on the outside by end layers 18 and 20.

[0063] Regarding the matrix material, it can be set to contain plastics, which are selected from the group consisting of: polyamides (especially polyamide 6 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), polyamide 11 (PA11)), polyolefins (especially polyethylene (PE), polypropylene (PP)), polyphenylene sulfide (PPS), thermoplastic polyurethane (TPU), polyphthalamide (PPA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (PEI), polyetheretherketone (PEEK), polystyrene (PS), styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene copolymer (ABS), polysulfone (PSU), and polylactic acid (PLA).

[0064] The fibers may have a fiber length in the range of about ≥10 mm, wherein the fibers are in a structure selected from woven fabrics, nonwoven fabrics, tapes, loosely woven fabrics, or laminated fabrics. Alternatively or additionally, it may be advantageous to select fiber materials from glass, aramid, basalt, natural fibers, or mixtures thereof. In terms of maintaining advantageous breakdown or dielectric properties of the busbar insulator even after a heat load of at least 450°C for at least 5 minutes, fibers based on one or more non-flammable electrical insulating components disclosed herein are most preferred. Particularly preferably, based on the total insulation material, the fibers may be present in the matrix material at a fiber volume fraction of ≥30 vol% to ≤90 vol%.

[0065] In one specific embodiment, the fiber material may include fibers with a length ≥10 mm, such as woven fabrics, nonwoven fabrics, tapes, loose fabrics, or laminated fabrics based on at least one raw material selected from the list of glass, aramid, basalt, natural fibers, or mixtures thereof, and the matrix material may include thermoplastics selected from the list of: polyamides (particularly polyamide 6 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), polyamide 11 (PA11)), polyamide 66 (PA46), polyamide 1010 (PA10.10), polyamide 11 (PA11)), polyamide 66 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), polyamide 11 (PA11)), polyamide 66 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 12 (PA12), polyamide 12 (PA12), polyamide 12 (PA13 ... Olefins (especially polyethylene (PE), polypropylene (PP)), polyphenylene sulfide (PPS), thermoplastic polyurethane (TPU), polyphthalamide (PPA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polycarbonate (PC), polyetherimide (PEI), polyetheretherketone (PEEK), polystyrene (PS), styrene-acrylonitrile copolymer (SAN), acrylonitrile-butadiene-styrene copolymer (ABS), polysulfone (PSU), and polylactic acid (PLA). Based on the above description, continuous fiber textiles are preferably based on one or more raw materials selected from the list consisting of glass and basalt.

[0066] The use of fiber-encapsulated plastic composite materials for busbar insulation has significant advantages. Even in the event of a fault or fire, and even in the event of matrix damage, the existing fibers act as spacers and thus as insulators, remaining around the busbar. This further ensures insulation performance even in the presence of air.

[0067] Example:

[0068] The positive effects of the bus insulator 10 according to the invention are shown in the following embodiments for determining the dielectric strength properties (also known as electrical breakdown resistance) of the composite material to which the bus insulator 10 according to the invention can be formed.

[0069] A 20mm thick flat aluminum plate was used as the grounding electrode. The high-voltage electrode consisted of a large 80 x 80mm² aluminum profile with rounded edges, machined and polished. High voltage was supplied via a transformer and a unidirectional rectifier with a 25 nF mesh capacitor. Five identical samples were tested accordingly.

[0070] Regarding the samples, these samples consist of a polyamide 6 matrix and embedded glass fiber fabric (fiber volume ratio of 47%), or consist of glass fiber fabric alone.

[0071] The first sample was formed as a plastic-fiber composite plate with a thickness of 1 mm and dimensions of 310 mm × 320 mm. No flashover or electrical breakdown was observed after 60 seconds of exposure to 30 kV DC.

[0072] The second sample was formed as a plastic-fiber composite plate with a thickness of 1 mm and dimensions of 150 mm × 150 mm. No flashover or electrical breakdown occurred after being subjected to a voltage of 20 kV DC for 60 seconds.

[0073] The third sample was formed from a fabric pad made solely of fibrous material. These samples were provided in two layers and tested in 150 mm × 150 mm dimensions. No flashover was observed during a 60-second test at 3 kV DC.

[0074] The fourth specimen was formed from a single layer of fibrous fabric. These specimens were tested at a size of 150 mm × 150 mm. A voltage of 1.9 kV DC was applied for 60 seconds. No flashover was recorded for the four specimens, and for one specimen, only breakdown was recorded after 40 seconds.

[0075] To test the temperature resistance of the insulation properties, the dielectric strength of a 1 mm thick monolayer pad or tape (pad) was tested after storage at 500°C for 5 minutes. Breakdown was not determined at less than 3.9 kV. For the corresponding pad with a total thickness of 3 mm, breakdown could not be determined at less than 9.5 kV.

[0076] The inventors discovered that for similar samples of fibrous materials not incorporated into a plastic matrix, or for similar samples containing organic fibers, the aforementioned advantages in preventing electrical breakdown are diminished or lost. Unwilling to be bound by theory, organic fibers exhibit relatively poor performance compared to mineral / inorganic fibers. For example, the inventors found that aromatic polyamides begin to degrade from approximately 400°C, while other polymer fiber structures tend to degrade / melt earlier.

[0077] Reference Signs

[0078] 10 Busbar Insulator

[0079] 12 busbars

[0080] 14 Insulation Materials

[0081] 16 core layers

[0082] 18 end layers

[0083] 20 End layer.

Claims

1. A busbar insulator (10) for insulating a busbar (12), wherein, The bus insulator (10) comprises a composite material comprising a polymer matrix material and a fiber material disposed in the matrix material, wherein the polymer matrix comprises a thermoplastic polymer component, and wherein the fiber material is based on one or more non-flammable inorganic components.

2. The busbar insulator (10) according to claim 1, wherein, The bus insulator (10) has an electrical breakdown voltage of at least 700V DC, and the breakdown voltage after being subjected to a heat load of at least 450°C for at least 5 minutes is within the range defined above.

3. The busbar insulator (10) according to any one of claims 1 or 2, wherein, The fiber material has a fiber length in the range of ≥10 mm.

4. The busbar insulator (10) according to any one of claims 1 to 3, wherein, The fibers have a structure selected from woven fabrics, nonwovens, tapes, or loose fabrics.

5. The busbar insulator (10) according to any one of claims 1 to 4, wherein, The fiber material is based on raw materials selected from the list of the following: glass; basalt; or a mixture thereof.

6. The busbar insulator (10) according to any one of claims 1 to 5, wherein, The matrix material is selected from thermoplastic plastics.

7. The busbar insulator (10) according to any one of claims 1 to 6, wherein, The matrix material includes plastics selected from the group consisting of: polyamides, particularly polyamide 6 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), and polyamide 11 (PA11); polyolefins, particularly polyethylene (PE) and polypropylene (PP); polyphenylene sulfide (PPS); thermoplastic polyurethane (TPU); polyphthalamide (PPA); polybutylene terephthalate (PBT); polyethylene terephthalate (PET); polycarbonate (PC); polyetherimide (PEI); polyetheretherketone (PEEK); polystyrene (PS); styrene-acrylonitrile copolymer (SAN); acrylonitrile-butadiene-styrene copolymer (ABS); polysulfone (PSU); and polylactic acid (PLA).

8. The busbar insulator (10) according to any one of claims 1 to 7, wherein, The composite material includes at least one core layer (16) comprising fibrous material, which is laminated between end layers (18, 20) comprising non-fibrous matrix material.

9. The busbar insulator (10) according to any one of claims 1 to 8, wherein, The fiber material comprises fibers with a length ≥10 mm, such as woven fabrics, nonwoven fabrics, tapes, loose fabrics, or laminated fabrics based on at least one raw material selected from the group consisting of glass, basalt, or mixtures thereof, and wherein the matrix material comprises thermoplastics selected from the group consisting of: polyamides, particularly polyamide 6 (PA6), polyamide 66 (PA66), polyamide 12 (PA12), polyamide 46 (PA46), polyamide 1010 (PA10.10), and polyamide 11 (PA11); polyolefins, particularly... Specifically, these include polyethylene (PE), polypropylene (PP); polyphenylene sulfide (PPS); thermoplastic polyurethane (TPU); polyphthalamide (PPA); polybutylene terephthalate (PBT); polyethylene terephthalate (PET); polycarbonate (PC); polyetherimide (PEI); polyetheretherketone (PEEK); polystyrene (PS); styrene-acrylonitrile copolymer (SAN); acrylonitrile-butadiene-styrene copolymer (ABS); polysulfone (PSU); and polylactic acid (PLA).

10. The busbar insulator (10) according to any one of claims 1 to 9, wherein, Based on the composite material, the fiber material is present in the matrix material in an amount of ≥30% to ≤90% by volume.

11. Busbar insulator (10) for the purpose of insulating the busbar (12), wherein, The bus insulator (10) is formed according to any one of claims 1 to 10.

12. A bus (12) for connecting an energy storage device to another energy storage device or to an electric motor, said bus (12) being provided with a bus insulator for electrically insulating said bus (12), wherein, Busbar insulator (10) is designed according to any one of claims 1 to 10.

13. An energy storage system, comprising at least one energy storage device for supplying electrical energy to an electric motor, wherein, The energy storage system includes at least one bus (12) for electrically connecting the energy storage device to another energy storage device or to the motor, wherein the bus (12) is arranged according to claim 12.

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