Electrical insulating device for an electrical appliance

Abstract

Electrical insulating device (1) for an electrical device (2), in particular for a high-voltage storage device, wherein the electrical insulating device (1) comprises at least one plastic material (5) and is configured to electrically insulate a first electrical conducting element (3), in particular an anode, from a second electrical conducting element (4), in particular a cathode, wherein the electrical insulating device (1) has ceramic particles (6) arranged in the plastic material (5) which are configured above a limit temperature, in particular a melting temperature, of the plastic material (5) to electrically insulate the first electrical conducting element (3) from the second electrical conducting element (4).

Description

[0001] The invention relates to an electrical insulating device for an electrical device, in particular for a high-voltage storage device, wherein the electrical insulating device comprises at least one plastic material and is configured to electrically isolate a first electrical conducting element, in particular an anode, from a second electrical conducting element, in particular a cathode.

[0002] Electrical insulating devices for electrical equipment, for example for high-voltage storage systems, are generally known from the prior art. These are typically made of a plastic material and arranged around or between electrical conductors to electrically insulate the conductor(s). For example, such a plastic material can be applied as an insulating device around at least one electrical conductor or inserted between two electrical conductors. This interrupts direct contact between the conductors or galvanically isolates them from one another, and also typically establishes a defined air and creepage distance between the conductors.

[0003] The conductive elements can be, for example, an anode and a cathode of an electrical energy storage cell or of different electrical energy storage cells, or at least one of the conductive elements can be a cell connector that connects several terminals of different electrical energy storage cells. Accordingly, it is essential to prevent a short circuit or an unintended electrical connection between one conductive element and another.

[0004] However, operating situations are possible in which the temperature within the electrical device rises. In these cases, the temperature may exceed limit values ​​or rise into temperature ranges that could lead to a change in the electrical insulation. For example, if the glass transition temperature of the plastic material forming the electrical insulation is reached, or if the melting point of the plastic material is reached, the plastic material may change its shape or melt.

[0005] In this case, the insulating effect of the electrical insulating device can be impaired, or, if the electrical insulating device is damaged, at least locally, due to the rising temperature, its insulating properties can be lost. In the worst case, direct electrical contact can occur between the two conductive elements that are meant to be isolated from each other by the electrical insulating device if the device is damaged, for example, above the melting temperature of the plastic material. Even with only partial damage to the plastic material, such as deformation, the air and creepage distances between the conductive elements can be reduced to an unacceptable level.

[0006] The invention is based on the objective of providing an improved electrical insulation device that is particularly more resistant to temperature changes.

[0007] The problem is solved by an electrical insulating device having the features of claim 1. The dependent claims relate to possible embodiments.

[0008] As described, the invention relates to an electrical insulating device for an electrical device, specifically a high-voltage storage device. The electrical insulating device is fundamentally designed to electrically isolate two conductive elements from each other, for example, to electrically isolate a first conductive element, specifically an anode, from a second conductive element, in particular a cathode. An electrical potential or voltage is thus present between the two conductive elements. Specifically, the electrical potential can be in the high-voltage range, i.e., several hundred volts or more than 1000 volts.

[0009] The invention is based on the finding that the electrical insulating device comprises ceramic particles arranged in the plastic material, which, above a limiting temperature, in particular a melting temperature, of the plastic material, are configured to electrically insulate the first electrical conductor from the second electrical conductor. In other words, the invention proposes using ceramic particles as a filler instead of the homogeneous plastic material commonly used.

[0010] Above a certain temperature threshold, for example, when the glass transition temperature or melting point of the plastic material is exceeded, the plastic material may deform, but the ceramic particles embedded within it retain their shape. This means that the electrical insulation can ensure insulation of the conductive elements largely independent of the temperature, as the ceramic particles remain in the space between the conductive elements. In particular, at least a residual level of insulation is guaranteed, even if the plastic material is damaged.

[0011] Even if the plastic material is completely destroyed, for example by melting or burning, the ceramic particles remain between the conductive elements, thus preventing direct electrical contact and ensuring a defined air and creepage distance. If, for example, a fault occurs in the electrical device where at least the glass transition temperature or the melting temperature of the plastic material is exceeded, the ceramic particles ensure that no short circuit can occur between the conductive elements. This improves the electrical safety of the device during operation, particularly in the event of thermal incidents.

[0012] The electrical insulating device can be manufactured, for example, using an injection molding process. As described, the ceramic particles can be added to the plastic material as a filler during the manufacturing process. The plastic material can therefore be referred to as the matrix or plastic matrix. The ceramic particles form a filler within the plastic matrix. Although deformation of the plastic material can still occur if the limit temperature is exceeded, the ceramic particles at least ensure that a minimum distance is maintained between the conductive elements.

[0013] As described at the outset, this document proposes the use of ceramic particles as a filler in the plastic material of the electrical insulating device. In one embodiment, the ceramic particles can have a higher melting point than the plastic material. Therefore, regardless of the plastic material used, it can always be ensured that the ceramic particles have a higher melting point than the plastic material. In principle, any ceramic particles can be used for this purpose. The melting point of the ceramic particles can, for example, be above 800 °C, specifically above 1000 °C or above 1200 °C. By way of example, metal oxides, such as aluminum oxide or lithium oxide, or more generally, technical ceramics can be used as ceramic particles.

[0014] As previously described, the ceramic particles can remain between the two conductive elements if the plastic material is damaged. In one embodiment of the electrical insulating device, the ceramic particles can define a minimum distance between the conductive elements, particularly when the plastic material is molten. In other words, the ceramic particles determine the maximum distance between the two conductive elements. For example, if the plastic material that electrically insulates the two conductive elements from each other partially or completely melts, at least the ceramic particles remain in the space between the conductive elements. Thus, the minimum distance is determined by the expansion of the ceramic particles, since the two conductive elements cannot be positioned closer together or approach each other more closely than the expansion of the ceramic particles allows.Since the ceramic particles themselves are not electrically conductive, they insulate the two conductive elements from each other.

[0015] In particular, it can be provided that the ceramic particles galvanically isolate the conductive elements, especially by defining a minimum distance, an air gap, and / or creepage distance. As described, the ceramic particles are also present between the conductive elements in the molten state of the plastic material or in the plastic material above the limiting temperature. The conductive elements can therefore approach each other so closely that a ceramic particle or the ceramic particles are in direct contact between them. This achieves at least galvanic isolation, as no direct electrical contact between the conductive elements can occur because the ceramic particles galvanically isolate them. Specifically, it can further be provided that the previously described minimum distance defines an air gap and / or creepage distance.The air and / or creepage distance is at least the dimension of the at least one ceramic particle located between the guiding elements. Furthermore, several layers of ceramic particles can be formed, so that their dimensions add up accordingly.

[0016] Furthermore, it follows that different ceramic particles can be used for different electrical insulating devices. These ceramic particles can differ fundamentally in their material, for example, which ceramic material is to be used. In addition, a difference in the particle size of the ceramic particles used can occur or be specified.

[0017] In one embodiment of the electrical insulating device, the particle size of the ceramic particles can be determined based on the electrical potential of the conductive elements. For example, the size of the ceramic particles can increase with increasing electrical potential. This means that the greater the electrical potential between the conductive elements, the larger the particle size of the ceramic particles can be. For instance, a maximum expected or possible electrical potential can be used to determine the particle size. For this purpose, a maximum voltage of the high-voltage storage device could be used, for example.

[0018] In a further embodiment of the electrical insulating device, a particle size can be specified based on an air and creepage distance table, in particular between 200 µm and 5 mm. The air and creepage distance table specifies which air and creepage distances must be maintained for a particular electrical voltage or potential. From this, it can be determined for which electrical potential between the conductive elements a specific particle size is sufficient.

[0019] It is generally possible to select the same particle size for all ceramic particles or to select different sizes, specifically for different conductive elements or potentials to be insulated, and particularly for different areas of the electrical device. For example, electrical insulating devices can be located at different points within the electrical device, or different conductive elements can be insulated with different electrical insulating devices or different sections of the same electrical insulating device. This makes it possible, on the one hand, to use the highest electrical potential to be insulated by the electrical insulating device as the basis for selecting the particle size, or, on the other hand, to use different ceramic particles for different electrical potentials.

[0020] As previously described, in addition to the size and material selection, the shape of the ceramic particles can also be specified. For example, the ceramic particles can be spherical, and / or it can be stipulated that a dimension perpendicular to the guide elements corresponds to the minimum distance. If the ceramic particles are spherical, it follows that the diameter must at least correspond to the minimum distance. Since the orientation of the spherical ceramic particles is therefore arbitrary, the minimum distance is ensured regardless of their orientation. Alternatively, the ceramic particles can also be designed as cylinders, rods, ribs, or columns. In this case, the ceramic particles can be randomly distributed within the plastic material, or a directed distribution within the plastic material can be provided, in particular with the longest direction of extension perpendicular to the guide elements.The random distribution takes advantage of the fact that at least some of the ceramic particles will end up in the desired orientation.

[0021] According to a further embodiment, the electrical insulating device can comprise at least two different ceramic particles, particularly for different areas to be insulated. As already described at the outset, the electrical insulating device can, for example, comprise different individual insulating elements designed for insulating different conductive elements. Depending on the potential of the individual conductive elements, it is possible for the individual insulating elements to be manufactured from plastic material containing different ceramic particles.

[0022] For example, a first electrical potential between two conductive elements may be lower than a second electrical potential between two other conductive elements. To isolate the first electrical potential, smaller ceramic particles may suffice, compared to smaller ceramic particles embedded in a plastic material within an insulating element designed to isolate the second electrical potential. The individual insulating elements can be combined by the electrical insulation device, even if they are spatially separated.

[0023] In a further embodiment of the electrical insulating device, it can be designed as a base plate that supports at least one cell connector of a high-voltage storage device. The base plate can also be referred to as a "carrier board." This electrical insulating device thus ensures that a cell connector, which is connected, for example, to a cathode of the electrical energy storage device of the high-voltage storage system, remains galvanically isolated from an anode of the electrical energy storage device. The electrical insulating device can, for example, be arranged on a conductive element, for example, be injection-molded onto the conductive element, or it is possible to manufacture the electrical insulating device separately and, for example, insert it between two electrical conductive elements.

[0024] In addition to the electrical insulation device, the invention relates to a high-voltage storage device which has a previously described electrical insulation device.

[0025] All advantages, details, designs and / or features described in relation to the electrical insulation device are fully transferable to the high-voltage storage device.

[0026] The invention is explained with reference to exemplary embodiments and the figures. The figures are schematic representations and show: Fig. 1. A schematic representation of a high-voltage storage device with an electrical insulating device according to an exemplary embodiment; and Fig. 2 A schematic representation of a high-voltage storage device with an electrical insulation device according to an exemplary embodiment.

[0027] Fig. Figure 1 schematically shows an electrical insulating device 1 for an electrical device 2, particularly in a first state, for example, below a limit temperature. The electrical device 2 can, for example, be a high-voltage storage device, specifically for a motor vehicle. The electrical insulating device 1 is configured to electrically isolate a first conductive element 3 from a second conductive element 4. For example, the first conductive element 3 can be a cell connector that connects the cathodes of electrical energy storage cells of the high-voltage storage device. The second conductive element 4 can accordingly be configured as an anode or be connected to one. The conductive elements 3 and 4 thus have different electrical potentials, or an electrical voltage is present between them.

[0028] In other words, the electrical insulating device 1 separates the conductive elements 3 and 4 from each other, or electrically isolates them from each other. In particular, the electrical insulating device 1 provides galvanic isolation between the first conductive element 3 and the second conductive element 4. How Fig. As can be seen further in Figure 1, the electrical insulating device 1 comprises a plastic material 5. The plastic material can also be referred to or considered as a "plastic matrix". Ceramic particles 6 are embedded in the plastic material 5, or the plastic material 5 comprises ceramic particles 6 arranged within the plastic material 5.

[0029] The ceramic particles 6 are shown as spheres for illustrative purposes only; however, it is equally possible that the ceramic particles 6 have a different shape, for example, they could be cylinders. The ceramic particles 6 are themselves not electrically conductive, so the air and creepage distances of the insulating device 1 are not affected by the ceramic particles 6.

[0030] Fig. Figure 1 shows an initial state of the electrical insulating device 1, for example, below a limit temperature. The limit temperature can be arbitrarily defined or predetermined by the plastic material 5. If the limit temperature is exceeded, the plastic material 5 can change its state, shape, or structure. For example, the limit temperature can be defined as the glass transition temperature for the plastic material 5. Similarly, the limit temperature can be considered to be the melting temperature of the plastic material 5.

[0031] Fig. Figure 2 shows, for example, the state of the electrical insulating device 1 after the limit temperature has been exceeded. For example, the plastic material 5 can become liquid upon exceeding the limit temperature, or it can deform plastically once the limit temperature has been exceeded. If the temperature acting on the electrical insulating device 1 becomes higher, the plastic material 5 can melt or burn completely.

[0032] The ceramic particles 6 have a different limiting temperature than the plastic material 5. In particular, the ceramic particles 6 have a higher melting point. If the limiting temperature for the plastic material 5 is exceeded, the plastic material 5 changes, but the ceramic particles 6 do not.

[0033] Fig. Figure 2 shows, for example, that even if the plastic material 5 melts or flows, galvanic isolation between the conductive elements 3 and 4 is maintained due to the ceramic particles 6. The ceramic particles 6 remain between the conductive elements 3 and 4 even if the plastic material 5 is damaged by exposure to temperatures above the limiting temperature or is partially or completely removed. The ceramic particles 6 thus prevent direct contact between the conductive elements 3 and 4 and therefore galvanically isolate them from each other.

[0034] Fig.Figure 2 further shows that a minimum distance 7 is ensured by the ceramic particles 6. Even if the plastic material 5 is completely removed and the ceramic particles are thus in contact with both guide elements 3, 4, the guide elements 3, 4 cannot come closer to each other than the diameter or largest dimension of the ceramic particles 6, especially perpendicular to the surfaces of the two guide elements 3, 4. It is also possible that several layers of ceramic particles 6 lie on top of each other and that these layers of ceramic particles 6 separate the guide elements 3, 4 from each other.

[0035] The minimum distance 7 thus ensures not only galvanic isolation between the conductive elements 3 and 4, but also an air and / or creepage distance. The number of ceramic particles 6, their shape, and / or the particle size of the ceramic particles 6 can be determined, for example, based on a potential or potential difference between the conductive elements 3 and 4. For instance, it can be determined what the maximum potential or voltage of the electrical device 2 is during operation, or what the maximum voltage that can occur between the conductive elements 3 and 4 during operation can be.

[0036] Based on this, the design of the ceramic particles 6 can be carried out, in particular their particle size can be determined. The particle size can, for example, range between 200 µm and 5 mm. For spherical ceramic particles 6, the particle size can be, for example, the diameter. If the ceramic particles 6 are not spherical, but cylindrical, for example, the particle size can be defined as the largest or smallest dimension. If the ceramic particles 6 deviate from a spherical shape, either random or directed orientation of the ceramic particles 6 can be carried out.

[0037] As previously described, the configuration of the ceramic particles 6 can be determined based on the electrical potential to be isolated by the electrical insulating device 1. The electrical insulating device 1 can have at least two or more insulating elements, each containing different ceramic particles 6 embedded in the plastic material 5. For example, different sections of the electrical insulating device 1 can be filled with different ceramic particles 6, enabling them to insulate different conductive elements 3, 4 from one another. Alternatively, the electrical insulating device 1 can also have individual or separate insulating elements containing different ceramic particles 6 embedded in the same or different plastic materials 5.

[0038] This means that a first electrical insulating element can be provided for isolating a first electrical potential, for example between the conductive elements 3 and 4, and at least one second electrical insulating element can be provided for isolating a second electrical potential, for example between other conductive elements 3 and 4. The first insulating element can comprise a first plastic material 5 and first ceramic particles 6, and the second insulating element can comprise a second plastic material 5 and second ceramic particles 6. The first plastic material 5 and the second plastic material 5 can be the same or different, and / or the first ceramic particles 6 and the second ceramic particles 6 can be the same or different.

[0039] In principle, the electrical insulating device 1 can be designed as a base plate or have one. The base plate can, for example, support a cell connector of a high-voltage storage device or a cell connector of the electrical device 2. The electrical insulating device 1 can therefore be referred to or considered as a "carrier board".

[0040] The advantages, details, and features described in relation to the individual embodiments can be combined, interchanged, and transferred to one another as desired. The electrical insulating device 1 can be a component of a high-voltage storage device, or a high-voltage storage device, for example, the electrical device 2, can comprise at least one such electrical insulating device 1. The preceding description is therefore also fully transferable to such a high-voltage storage device. REFERENCE MARK LIST 1 electrical insulating device 2 electrical devices 3, 4 guide element 5 plastic material 6 ceramic particles 7 Minimum distance

Claims

[1] Electrical insulating device (1) for an electrical device (2), in particular for a high-voltage storage device, wherein the electrical insulating device (1) comprises at least one plastic material (5) and is configured to electrically insulate a first electrical conductor (3), in particular an anode, from a second electrical conductor (4), in particular a cathode, characterized by , that the electrical insulating device (1) comprises ceramic particles (6) arranged in the plastic material (5) which are designed above a limit temperature, in particular a melting temperature, of the plastic material (5) to electrically insulate the first electrical conducting element (3) from the second electrical conducting element (4). [2] Electrical insulating device (1) according to claim 1, characterized by that the ceramic particles (6) have a higher melting temperature than the plastic material (5). [3] Electrical insulating device (1) according to claim 1 or 2, characterized by , that the ceramic particles (6) establish a minimum distance (7) between the guide elements (3, 4), especially in a molten state of the plastic material (5). [4] Electrical insulating device (1) according to claim 3, characterized by , that the ceramic particles (6) galvanically isolate the conductive elements (3, 4), in particular the minimum distance (7) defines an air and / or creepage distance. [5] Electrical insulating device (1) according to any one of the preceding claims, characterized by , that a particle size of the ceramic particles (6) is determined depending on an electrical potential of the conducting elements (3, 4). [6] Electrical insulating device (1) according to any one of the preceding claims, characterized by , that a particle size is specified based on an air and creepage distance table, in particular between two hundred µm and 5 mm. [7] Electrical insulating device (1) according to any one of the preceding claims, characterized by that the ceramic particles (6) are spherical and / or that a dimension perpendicular between the guide elements (3, 4) corresponds to the minimum distance (7). [8] Electrical insulating device (1) according to any one of the preceding claims, characterized by , that the electrical insulating device (1) comprises at least two different ceramic particles (6), in particular for different areas to be insulated. [9] Electrical insulating device (1) according to any one of the preceding claims, characterized by , that the electrical insulating device (1) is designed as a base plate which carries at least one cell connector of a high-voltage storage device. [10] High-voltage storage device comprising at least one electrical insulating device (1) according to any one of the preceding claims.

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