Multi-layer insulation element for battery

Abstract

To provide a multi-layer insulating element for the thermal insulation of a battery, in which a covering layer is weak in bending and the thermal insulation element as a whole is compressible and flexible, a battery including such an insulating element, and a method for using the insulating element.SOLUTION: A multi-layer insulation element 1 includes a first covering layer 2, a second covering layer 3, and a compressible and flexible intermediate material 4 which includes at least one heat-resistant fiber layer 5 and is arranged between the first covering layer 2 and the second covering layer 3, and the heat-resistant fiber layer 5 is formed from a needled nonwoven fabric and at least one of the first covering layer 2 and the second covering layer 3 is a heat-resistant mica layer, preferably a mica paper layer or a mica plate.SELECTED DRAWING: Figure 1B

Description

[Technical field]

[0001] The present invention relates to a multi-layer insulating element for the thermal insulation of a battery according to the preamble of claim 1, to a battery comprising a multi-layer insulating element according to the preamble of claim 35 and to the use of a multi-layer insulating element according to the preamble of claim 49. [Background technology]

[0002] In the present invention, the term "thermal insulation element" is preferably to be understood as a flat part consisting of a layer structure, in particular a layer package, designed and / or used for the thermal insulation of a battery. In particular, the thermal insulation element is configured to reduce and / or delay the release of heat into the environment, in particular into the vehicle cabin, and / or to inhibit and / or reduce and / or delay the spread of heat in the battery in the event of uncontrolled and / or excessive heat development in the battery. In the present invention, the term "battery" is to be understood as meaning in particular a rechargeable storage element and / or secondary element for providing electrical energy by converting chemical energy. A battery is preferably composed of several interconnected accumulator cells and / or cell blocks, i.e. battery cells. In particular, the battery is configured as a traction battery and / or for driving an electric vehicle and / or as a lithium-ion battery, where reliable and / or effective thermal insulation is important in order to protect the vehicle occupants in the event of battery overheating, for example as a result of a road accident, at least until the arrival of rescue services.

[0003] Due to their chemical composition, lithium-ion batteries in particular exhibit a relatively high instability. If a local short circuit of the electrodes occurs, for example due to contamination of the separator separating the internal electrodes in the battery cell, due to trapped foreign particles and / or mechanical action or damage, a strong short circuit current will heat the battery cell up to 800°C, sometimes even up to 1300°C, in a short time. This process is known as thermal runaway. In particular, since the separator loses stability at relatively low temperatures, for example above 120°C, the thermal runaway of one battery cell can easily and / or quickly spread to other, adjacent battery cells, thus causing a rapid short circuit in the adjacent battery cells. This leads to an unstoppable chain reaction, in which the energy stored in the battery is released in a short time, usually explosively and with the release of debris. Against this background, it is desirable to keep battery cells adjacent to a runaway or overheating battery cell at a certain limit temperature, preferably below 120° C., in particular below 80° C., for as long as possible. Above 80° C., the degradation process of the battery cell is significantly accelerated, and above 120° C., separators in the battery cells often start to melt, with irreversible damage and / or short circuits. Similarly, there is a high demand for efficient and / or long-lasting thermal protection of adjacent areas and / or rooms, especially vehicle cabins, against uncontrolled heat development in the battery. In particular, occupants and / or objects should be protected from heat until rescue and / or recovery procedures are fully completed.

[0004] DE10134145A1 relates to a fire-resistant battery housing. The battery housing contains a thermoactive material, for example aluminum silicate or gibbsite, which is deformed above a certain temperature, whereby the thermal energy further supplied is consumed for progressive deformation and thus the temperature rise is at least slowed down. In this case, since it is not possible to arrange a protective material between the battery cells, an effective containment of the thermal cycles is not possible or at best only very difficult to achieve, transformations can lead to mechanical stress or destruction of the battery cells and there is a risk that the thermoactive material will prematurely burst and thus lose its thermal insulation function.

[0005] AT518161A4 relates to a battery having a plurality of battery cells, at least two adjacent battery cells being thermally insulated from each other by a protective material. Above a certain temperature, the protective material expands and the battery cells insulated from each other are pushed away from each other by the increase in the volume of the protective material expanding under the effect of temperature, thus further thermally isolating and / or insulating the battery cells from each other. A disadvantage is that the increase in the volume of the protective material - especially in addition to the pressure increase due to thermal development - results in an expansion pressure in the battery, with a corresponding increase in the risk of battery rupture and / or damage to and destruction of the battery cells. From US Pat. No. 8,541,126 (B2) an insulating element for the thermal insulation of batteries is known. The insulating element is arranged between two adjacent battery cells. The insulating element has a layered structure with an intermediate layer arranged between two covering layers. The intermediate layer has a higher thermal conductivity than the covering layer. The covering layer can be designed as a fibrous layer of ceramic or refractory fibers. A disadvantage is that the insulating element is brittle due to the formation of fibers and can burst and / or break even under low pressure loads. This is not only associated with a significant loss or even loss of the thermal insulating function, but also leads to damage to adjacent and / or nearby battery cells and ultimately increases the risk of explosion.

[0006] EP 3142166 A1 relates to an insulating element comprising rigid mica plates and compressible short fibre and / or refractory fibre layers arranged and / or stacked on top of one another. A disadvantage is that flexible adaptation and / or shaping, in particular for installation in a battery, is not possible. Also, the insulating element with its brittle mica plates and its short fibre fibre mat can easily burst and / or break as a result of uncontrolled heat development and associated pressure rise, leading to damage to the surroundings and / or prematurely losing its thermal insulating function. Finally, the high unit area mass is a disadvantage, in particular for vehicles. Summary of the Invention

[0007] The object of the present invention is to provide a multi-layer insulating element for the thermal insulation of a battery, which allows and / or supports efficient thermal insulation and / or a robust and / or resistant structure and / or a flexible and / or easy assembly and / or integration into the battery, a battery comprising such an insulating element, and a method for using the same. The above object is solved by a multilayer insulating element according to claim 1, by a battery according to claim 35 or by a use according to claim 49. Advantageous further developments are the subject of the subclaims.

[0008] The first aspect of the present invention is that the fiber layer is formed from long fibers with a length of more than 30 mm and / or from a needled or bonded nonwoven. The long fibers and / or needling and / or bonding of the fiber layer significantly increase the mechanical resistance compared to another fiber layer. Thus, the fiber layer according to the present invention is on the one hand stretchable and pressure elastic, allowing the absorption of high compressive forces. At the same time, the fiber layer has a high thermal insulation capacity, since the entangled fibers effectively reduce the passage of thermal energy through the fiber layer. This is particularly advantageous in the case of uncontrolled heat generation in the battery, for example when thermal runaway of a battery cell occurs, since this significantly delays the complete destruction or explosion of the battery. Finally, the needled nonwoven has a low mass per unit area, making it easy to handle. Preferably, the fibrous layer is made from needled and / or bonded glass fibres or silicate fibres or mixtures thereof. Particularly preferably, the fibres of the fibre layer have a length of at least 40 mm, preferably at least 50 mm, in particular essentially 50 mm to 60 mm, which allows a particularly high pressure and tear resistance of the fibre layer. In particular, the fibres have an average diameter of at least 4 μm, preferably at least 5 μm, in particular between 6 μm and 15 μm. It is particularly preferred that the fibrous layer be binder-free and / or free of melt beads. Preferably, the fiber layer and the intermediate material each have a density of 1000 g / m 2 Less than 800 g / m 2 Less than 600g / m2 Less than and / or 150 g / m 2 More than 200 g / m 2 More than 300 or 400 g / m 2 The mass per unit area is greater than 1.0 mm, which allows for easy handling.

[0009] According to a second aspect of the invention, which can also be realized independently, the covering layer is designed to be flexibly and / or flexibly in order to make the insulation element both compressible and flexible and / or elastically flexible. This allows for flexible adaptation to different installation situations and / or better adaptation in case of high loads, for example in case of a battery cell bursting, so that the insulation element is more resistant to destruction and / or loss of its insulation function. Finally, the release of debris is significantly reduced. Preferably, at least one covering layer is designed to be liquid-tight, preferably waterproof. In addition, one of the covering layers, preferably both covering layers, is designed to be water-repellent and / or air-tight. In this way, the intermediate material and / or the fiber layer are efficiently protected, thus ensuring efficient thermal insulation even in wet and / or gaseous environments. Preferably, at least one coating layer is designed as a refractory metal layer, preferably an aluminum layer. Alternatively, at least one covering layer may be formed as a heat-resistant plastic layer, preferably a polyimide layer, or as a heat-resistant woven fabric layer, preferably a glass fabric layer. The covering layer, designed as a metal, plastic or woven fabric layer, is preferably less than 100 μm, particularly preferably less than 80 μm, in particular between 20 μm and 50 μm thick.

[0010] According to a preferred design, the insulation element has a layer of woven fabric. The woven fabric can form at least one covering layer and / or additional layer. Preferably, the woven fabric is arranged on the outside of the insulation element. The woven fabric may comprise or consist of metal fibers, in particular stainless steel fibers and / or aluminum fibers, glass fibers, carbon fibers, silicate fibers and / or mixtures thereof. In particular, the mechanical stability of the insulation element can be significantly increased and / or improved by using the woven fabric as a covering layer. This is particularly advantageous as a mechanical protection in case of a battery cell explosion. Preferably, at least one of the covering layers and / or the insulating element is made gas permeable and / or gas permeable, for example when the covering layer comprises or is formed by a woven fabric, which may reduce the risk of explosion of the battery sealed and / or surrounded by one or more insulating elements, since explosive gases can thus be released through the covering layer.

[0011] Particularly preferably, at least one or both coating layers are designed as heat-resistant mica layers, preferably as mica paper layers or mica sheets. In particular, the coating layer formed as a mica layer has a thickness of less than 3 mm, preferably less than 2 mm, in particular less than 1 mm, particularly preferably between 0.05 mm and 0.15 mm. This allows high heat resistance and at the same time flexibility and / or pliability. Particularly preferably, the first covering layer is designed as a high-temperature resistant mica layer, preferably a mica paper layer, while the second covering layer is designed as an aluminum layer, preferably an aluminum foil. Alternatively, the second covering layer can also be designed as a plastic layer, preferably a polyimide layer. The above-mentioned material pairs allow the thermal insulation to be optimized. This has been confirmed by tests.

[0012] Particularly preferably, the intermediate material comprises two fiber layers, in particular of a needled nonwoven fabric, which are separated from each other by a heat-resistant and / or bending-weak intermediate layer. The multi-layer structure thus formed (two or more insulating and / or fiber layers separated by an intermediate layer) allows the insulating performance of the intermediate material to be further improved, since the intermediate layer in the intermediate material forms a thermal barrier between the fiber layers, thus further reducing and / or limiting the spread of heat through the intermediate material and / or the insulating element. This was also confirmed in tests. Particularly preferably, the intermediate layer is designed as a high-temperature resistant plastic layer, preferably a polyimide film, or an aluminum layer, in particular an aluminum foil. The intermediate layer is preferably less than 100 μm, particularly preferably less than 80 μm, in particular between 20 μm and 50 μm thick. Preferably, at least one coating layer and / or intermediate layer has a dielectric strength of more than 1 kV / mm, preferably more than 1.5 kV / mm, in particular more than 2 kV / mm, which avoids and / or delays the formation of electric arcs or sparks. In particular, the insulating element - preferably when installed - has a thickness of less than 7 mm, preferably less than 6 mm, in particular between 2 mm and 3 mm, which allows a flexible and easy installation in the battery even in narrow installation gaps.

[0013] In particular, the insulating element has an adhesive layer at least in places on at least one flat side or is adhesive at least in places on one flat side, which allows the insulating element to be easily positioned and / or attached to or in the battery and / or further insulating elements. Preferably, the coating layer and the intermediate material are glued or otherwise joined to form a bond, thus achieving a mechanically stable layered composite. In particular, the insulating element has a dielectric strength of more than 20 kV / mm, preferably more than 30 kV / mm, in particular between 40 kV / mm and 70 kV / mm. Preferably, the insulating element has a thickness of 1500 g / m 2 Less than 1300 g / m 2 Less than 1000g / m 2Less than and / or 150 g / m 2 More than 200 g / m 2 More than 300 or 400 g / m 2 It has a mass per unit area of ​​greater than 1000 MPa. The thermal conductivity of the insulating element at room temperature of 25° C. is less than 0.1 W / mK, preferably less than 0.08 W / mK, in particular less than 0.04 W / mK. A battery according to the proposal, preferably a lithium-ion battery, in particular in the form of a traction battery for electric vehicles, comprises a housing and at least one multilayer insulating element according to the proposal arranged in and / or on the housing for thermal insulation, which results in corresponding advantages.

[0014] Preferably, the insulating element closes and / or insulates the battery or battery cell or housing at least partially, preferably completely or over the entire surface, on the outside or inside of the surface. This allows effective insulation of the battery towards the outside and / or towards the area above and / or adjacent to the battery, in particular towards the vehicle cabin. In this way, people, occupants and / or objects in the area and / or in the cabin are effectively and / or for a sufficiently long time protected from uncontrolled heat development in the battery, i.e. until rescue and / or recovery procedures are completed.

[0015] Alternatively or additionally, a thermal insulating element can be placed between two adjacent battery cells in the housing to thermally insulate them from each other. In this way, a thermal runaway flashover from one battery cell to the next and / or adjacent battery cell is effectively delayed and / or inhibited, thus preventing or at least significantly delaying the explosive release of heat and / or debris from the battery. In particular, the insulating element is attached and / or fixed, preferably glued, to or within the housing lid and / or the housing surface of the housing. The insulating element can be attached, in particular over its entire surface, to the inside of the housing or the housing lid facing the housing interior and preferably to the front in the installed state, thus enabling an effective front-side insulation. Alternatively or additionally, the insulating element and / or another insulating element may be attached or aligned laterally and / or vertically on the inside, particularly so that the insulating element can be easily inserted between two adjacent battery cells. Alternatively or additionally, the insulating element and / or another insulating element can be arranged on the floor and / or on the inside of the underside of the housing interior, in this way it is possible to protect the battery against heat acting on it from below, for example in the case of a fuel fire on the road. Alternatively or additionally, insulating elements and / or separate insulating elements can be disposed inside the sidewalls and / or the inner sidewalls of the housing.

[0016] Preferably, at least two insulating elements are arranged in the battery, with at least one first insulating element insulating the housing and / or the housing interior at the front, and at least one second insulating element arranged between adjacent battery cells. In this way, corresponding advantages, which in principle can also be realized independently of each other, can be realized simultaneously, i.e., on the one hand, front-side insulation of the battery and on the other hand, delaying and / or reducing heat transfer between adjacent battery cells, packs or modules. In particular, the second insulating element is attached laterally and / or longitudinally to the first insulating element, preferably glued, sewn or otherwise firmly connected.

[0017] In the case of a battery according to the present proposal, it is particularly advantageous if the insulating element has at least one covering and / or additional layer of a woven fabric, preferably a metal mesh, in particular a wire mesh of stainless steel, which, as mentioned above, may allow explosive gases to escape through the covering layer and thus reduce the risk of the battery exploding. In addition, the covering or additional layer of woven fabric preferably provides high mechanical stability, so that passengers in the vehicle compartment can be effectively protected from debris in the event of a battery explosion. A filtering function for explosive and / or toxic and / or harmful gases can also be provided by the fabric, so that passengers in the vehicle compartment are protected from such gases. Preferably, the fabric is designed such that at least a portion of the gases is separated by the fabric. This reduces the risk to humans arising from such gases and / or exhaust gases.

[0018] In general, it should be noted that the proposed embodiment according to the invention improves and / or simplifies the thermal insulation and fire protection of the battery compartment, in particular for electric vehicles. In particular, the proposed thermal insulation element allows a very effective thermal insulation between the battery on the one hand and the vehicle compartment on the other hand, preferably a vehicle compartment arranged above and / or adjacent to the battery. Alternatively or additionally, the heat transfer and / or thermal runaway of the battery cells to adjacent battery cells is delayed and / or inhibited, thus preventing or at least significantly delaying destruction and / or explosion of the battery. In this way, sufficient time is provided for rescue and / or recovery, in which the occupants are adequately protected from uncontrolled thermal development in the battery. The aspects and features of the invention, besides those mentioned above, arising from the claims and the following description, can essentially be realized independently of one another in any combination and / or order. Further advantages, features, capabilities and aspects of the invention arise from the claims and the following description of preferred embodiments based on the drawings. [Brief description of the drawings]

[0019] [Figure 1A] FIG. 2 is a schematic cross-sectional view of a proposed multi-layer insulating element for thermal insulation. [Figure 1B] FIG. 2 is a schematic cross-sectional view of a multi-layer insulation element according to another embodiment. [Figure 1C] FIG. 2 is a schematic cross-sectional view of the proposed insulation element according to another further embodiment. [Figure 1D]FIG. 1 is a schematic diagram of a woven fabric. [Diagram 2] FIG. 2 is a schematic cross-sectional view of a battery with an insulating element disposed therein, disposed and / or installed in a vehicle as shown diagrammatically. [Diagram 3] FIG. 1 is a schematic cross-sectional view of a battery with a custom insulating element according to a further embodiment. [Figure 4] First experimental setup for carrying out temperature measurements on the proposed insulation element. [Diagram 5] Second experimental setup for carrying out temperature measurements on the proposed insulation element. [Figure 6] FIG. 1 shows a first temperature diagram measured on the proposed insulation element with a first layer structure. [Figure 7] FIG. 2 shows a second temperature diagram measured on the proposed insulation element with a second layer structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Figure 1A illustrates a multilayer insulation element 1 according to the proposal in a schematic, non-scale cross-sectional view. Figures 1B and 1C illustrate further embodiments of the multilayer insulation element 1 according to the proposal, also in schematic, non-scale cross-sectional views. The illustrated embodiments are similar to each other and can also be combined with each other as desired. In particular, the different Figures 1A, 1B and 1C serve only to highlight different preferred aspects. The thermal insulation element 1 is especially designed as a flat layer package. The insulating element 1 is particularly compressible and at the same time flexible.

[0021] The term "flexible" is preferably understood to mean a sufficiently low bending stiffness of the insulating element 1, the bending stiffness being a measure of the resistance of an acting force to bending deformation on the part and / or on the insulating element 1. The bending stiffness is preferably determined according to ISO 5628 2493. For this purpose, a plate-shaped insulating element 1 having certain dimensions, for example a thickness of 6 mm and a size of 60 mm x 40 mm, is clamped in a rotatable clamping device. The free end of the insulating element 1 contacts a sensor of a load cell, via which a corresponding contact force is recorded as the clamping device is rotated. In particular, the sensor contacts the free end of the insulating element 1 at a distance of 50 mm from the clamping point. The bending stiffness is determined in particular by the force measured by the sensor when the insulating element is bent by 15°. Preferably, the insulating element 1 has a bending stiffness thus determined of less than 10 N, preferably less than 5 N, in particular less than 1 N.

[0022] The term "compressible" is preferably understood to mean a sufficiently low compression hardness of the insulation element 1, the compression hardness representing the pressure required to compress the test specimen and / or the insulation element 1 by 40% of its original thickness. The compression hardness is preferably determined according to DIN EN ISO 3386 using a plate-shaped insulation element 1 having a thickness of 5 mm and a size of 300 mm x 200 mm as the test specimen and an aluminum plate having a thickness of 20 mm and a size of 190 x 80 mm as the indenter. Preferably, the insulation element 1 has a compression hardness thus determined of less than 40 kPa, preferably less than 30 kPa, in particular less than 20 kPa. The insulating element 1 is especially configured for the thermal insulation of a battery 8 as illustrated in Figure 2. A preferred structure of the battery 8 and a preferred arrangement of the insulating elements 1A, 1B in the battery 8 will be described later. The insulating element 1 comprises a first covering layer 2 and a second covering layer 3. The covering layers 2, 3 in particular each form one (outer) flat side of the insulating element 1. Preferably, a compressible and / or flexible intermediate material 4 is arranged between the cover layers 2, 3. The intermediate material 4 comprises at least one fiber layer 5 - in the illustrated embodiment two or more fiber layers 5.

[0023] The or each fiber layer 5 is preferably formed from a needled and / or bonded nonwoven. For the purposes of the present invention, the term "needled nonwoven" is preferably to be understood as a fabric whose fibers are randomly intertwined and thereby bonded by dry needling and / or needling without a binder and / or a molten bead. The fibre layer 5 is made in particular of glass fibres or silicate fibres or mixtures thereof. For example glass fibres, in particular of E, ECR or R glass or mixtures thereof, and / or other heat-resistant fibres may be used. The fibres preferably have an average diameter of at least 4 μm, in particular at least 6 μm, and most preferably essentially between 8 μm and 16 μm. The length of the fibres is preferably more than 30 mm, preferably more than 40 mm, in particular essentially 50 mm to 60 mm. In principle, however, the length of the fibres can also be greater, for example up to about 120 mm. Preferably, the fibrous layer 5 is free of binders and / or melt beads.

[0024] Preferably, the mass per unit area of ​​the fibrous layer 5 and / or the intermediate material 4 is greater than 1000 g / m 2 Less than 800 g / m 2 Less than 600g / m 2 Less than and / or 150 g / m 2 More than 200 g / m 2 More than 300 or 400 g / m 2 It's super. Preferably, the mass per unit area of ​​the insulating element 1 is 1500 g / m 2 Less than 1300 g / m 2 Less than 1000g / m 2 Less than and / or 150 g / m 2 More than 200 g / m 2 More than 300 or 400 g / m 2 It's super. Preferably, the fibre layers 5 of the intermediate material 4 are separated from one another by intermediate layers 6. The intermediate layers 6 are in particular formed by heat-resistant metal layers, preferably aluminium layers, but may also be formed by heat-resistant plastic layers, preferably polyimide layers. The insulation element 1 can also have several intermediate layers 6 and correspondingly several fibre layers 5, in particular two fibre layers 5 separated from each other by an intermediate layer 6.

[0025] The covering layers 2, 3 are preferably designed to be flexibly weak, i.e. easily flexible and / or flexible. A "flexibly weak" covering layer 2, 3 in the sense of the present invention is preferably paper-like, cloth-like or foil-like and / or has a thickness of less than 2 mm, in particular less than 1 mm. Particularly preferably, the covering layers 2, 3 have a thickness of more than 0.05 mm and / or less than 0.15 mm. This makes the entire insulation element 1 compressible and flexible, the compressibility being at least essentially due to the compressible design of the intermediate material 4. The covering layers 2 and 3, the intermediate material 4, the fibre layer 5 and / or the insulating element 1 are preferably heat-resistant, in particular heat-resistant up to at least 200°C, particularly preferably above 250°C, 500°C or 1000°C. Preferably, at least one of the covering layers 2, 3 is configured as a heat-resistant metal layer, preferably an aluminum foil, or as a heat-resistant plastic layer, preferably a polyimide foil, or as a heat-resistant woven fabric layer, preferably a glass cloth foil, or as a mica layer, preferably a mica paper layer.

[0026] Particularly preferably, one and / or the first covering layer 2 is configured as a heat-resistant mica layer, preferably a mica paper layer, and the other and / or the second covering layer 3 is configured as a metal layer, preferably an aluminum foil, or a plastic layer, preferably a polyimide foil. However, both covering layers 2, 3 may also be designed identically, in particular as a mica layer, preferably a mica paper layer. This allows for a particularly high heat resistance. An embodiment of the thermal insulation element 1 is particularly illustrated in FIG. 1B, in which the covering layers 2, 3 are designed identically, for example as mica layers each. According to a further embodiment, the insulation element 1 may comprise a woven fabric 21. The woven fabric 21 preferably forms an at least substantially planar and / or flat layer and / or a woven fabric layer. The term "woven fabric" refers in particular to a preferably flat product formed by a plurality of threads or wires which cross one another at least substantially at right angles, the threads and / or wires being guided above and below the weft threads and / or wires, in particular with a certain rhythmic and / or repeating sequence. Preferably, the woven fabric 21 forms one or both cover layers 2, 3. However, it is also possible for the woven fabric 21 to form an additional layer 22, which is preferably provided in addition to the cover layers 2, 3. The additional layer is illustrated in Figure 1C.

[0027] The woven fabric 21 is preferably a metal mesh, in particular a wire mesh made of stainless steel and / or aluminum. However, the woven fabric 21 can also be a glass fiber fabric, a carbon fiber fabric or a silicate fabric. It is also possible for the woven fabric 21 to be a blended fabric and / or to have or consist of a mixture of metal fibers, in particular stainless steel fibers and / or aluminum fibers, glass fibers, carbon fibers and / or silicate fibers. The additional layer 22 is preferably arranged on the outside of the insulation element 1. Alternatively, the additional layer 22 can be provided on the inside of the insulation element 1, for example between the covering layer 2, 3 and the fiber layer 5 and / or between the fiber layer 5 and the intermediate layer 6.

[0028] The covering layers 2, 3 of the woven fabric 21 are preferably laminated and / or glued to the textile layer 5 or are otherwise firmly connected to the textile layer 5. Particularly preferably, a gas-permeable and / or gas-permeable adhesive is used to connect the woven fabric 21 forming the covering layers 2, 3 to the textile layer 5, preferably the adhesive allowing gases to escape and / or pass through but forming a barrier against sparks or flames. This is particularly advantageous when using the insulating element 1 in a battery 8, which is described in more detail below. Furthermore, embodiments are possible in which the thermal insulation element 1 has both the additional layer 22 and the adhesive layer 7, preferably in this case the adhesive layer 7 being arranged on the first covering layer 2 and the additional layer 22 being arranged on the second covering layer 3, or vice versa. The fabric 21 preferably has high heat resistance, preferably up to a temperature of about 1150°C. The woven fabric 21, in particular the metal mesh, preferably has a mesh size of at least 0.1 mm and / or at most 0.4 mm. Particularly preferred mesh sizes are, for example, about 0.114 mm, about 0.22 mm and about 0.315 mm.

[0029] The woven fabric 21, in particular the metal mesh, preferably has an open screening area of ​​at least 30% and / or at most 60%. Particularly preferred open screening areas are, for example, about 37.0%, about 42.4% and about 51%. Preferably, at least one of the covering layers 2, 3 and / or the additional layer 22, in particular the woven fabric, is gas permeable.

[0030] Preferably, at least one covering layer and / or additional layer 22, in particular the woven fabric 21, is designed in such a way that explosive, toxic and / or harmful gases are removed and / or absorbed, e.g. mechanically and / or chemically, when they permeate the insulation element 1, the covering layers 2, 3 and / or the additional layers 22. Preferably, at least one covering layer 2, 3 and / or additional layer 22, in particular the metal mesh and / or the insulating element 1 as a whole, has such mechanical stability that no fragments can penetrate the insulating element 1 in the event of an explosion of the battery 8. The insulating element 1 preferably has a thickness, especially in the uncompressed or delivery state, of less than 15 mm, preferably less than 10 mm, in particular between 6 mm and 8 mm. Particularly preferably, the thermal insulation element 1 and / or the at least one covering layer 2, 3 and / or the intermediate layer 6 have a dielectric strength of more than 20 kV / mm, preferably more than 30 kV / mm, in particular between 40 kV / mm and 70 kV / mm. The covering layers 2, 3 and the intermediate material 4 are in particular connected to one another by gluing. In particular, a heat-resistant adhesive is used for this purpose. However, other connection techniques, such as sewing or welding, are also possible. Preferably and / or optionally, at least one covering layer 2, 3 - in this example the first covering layer 2 - has an adhesive layer 7 for attaching and / or fixing the insulating element 1 to a part of the battery 8 and / or to another insulating element 1, if necessary. The adhesive layer 7 consists in particular of an acrylate adhesive. The mass per unit area of ​​the adhesive layer 7 is preferably 150 g / m 2 Less than 120 g / m 2 Less than 50 and 100 g / m 2 Alternatively or additionally, the adhesive layer 7 may be designed as a double-sided adhesive tape. However, adhesive layer 7 is not essential, but merely optional, as can be seen especially from Figures 1B and 1C.

[0031] In the following, the proposed arrangement and / or the use of the proposed insulating elements 1A and 1B and optionally the proposed further insulating elements 1C and 1D in a battery 8 is explained in more detail on the basis of Fig. 2. The insulating elements 1A-1D can be designed identically or differently according to the above-described embodiments. Hereinafter, the insulating elements 1A to 1C are referred to as the first insulating element 1A, the second insulating element 1B, the third insulating element 1C, and the fourth insulating element 1D for the sake of distinction. However, this serves only to distinguish between different insulating elements, and does not mean, for example, that when the third insulating element 1D is provided, the second insulating element 1B must also be present. In particular, a battery 8 for the power supply is arranged and / or installed in a diagrammatically represented vehicle 14, in particular an electric vehicle. In particular, when installed, the battery 8 is provided in a passenger compartment 15, for example below a passenger or other interior area of ​​the vehicle 14. The battery 8 preferably has a housing 9 comprising a lower housing part 10 and an upper housing part and / or housing lid 11. The housing 9 preferably consists of a non-conductive material, for example plastic, or of metal.

[0032] Battery 8 is preferably designed as a rechargeable lithium-ion accumulator. Alternatively, it can be constructed or designed from or with lithium iron phosphate, lithium cobalt oxide, lithium metal oxide, lithium ion polymer, nickel zinc, nickel metal, nickel cadmium, nickel hydrogen, nickel silver, nickel metal hybrids and similar systems and / or materials. In particular, the battery 8 includes at least one group of battery cells 12 electrically interconnected and housed in a housing 9 , preferably a lower housing portion 10 . A first insulating element 1A is attached and / or fixed above the battery cells 12 and / or to the housing lid 11 of the housing 9, preferably by means of an adhesive, in particular by means of an adhesive layer 7.

[0033] Particularly preferably, the first insulating element 1A is attached over its entire surface to the inside 13 of the housing lid 11, the inside 13 facing towards the housing interior. The first insulating element 1A thus closes and / or insulates the lower housing part 10 and / or the battery 8 and / or its cells 12 on the front side. In this way, a particularly efficient front-side insulation and fire protection for the passenger compartment 15 is achieved in order to protect people or objects inside efficiently and / or for a long enough time from uncontrolled heat development in the battery 8. The airtight construction also prevents and / or reduces gas explosion-like propagation in the direction of the passenger compartment.

[0034] Particularly preferably, the second covering layer 3 of the first insulating element 1A facing the interior of the housing and / or towards the battery cells 12 is designed as a mica layer, preferably a mica paper layer, and the first covering layer 2 facing away from the battery cells 12 and / or the interior of the housing is designed for fastening to the housing lid 11 and is provided in particular with an adhesive layer 7. This improves the heat resistance and at the same time facilitates handling and / or fastening of the insulating element 1 to the housing 9. Alternatively or additionally, at least one (further and / or second) insulating element 1B is disposed between adjacent battery cells 12, in this example between two groups of battery cells 12, whereby the groups are thermally insulated and / or separated from each other. Particularly preferably, the insulating element 1B is inserted, pressed in, or otherwise placed between the battery cells 12.

[0035] In particular, the insulating element 1A and / or 1B seals and / or encapsulates at least one battery cell 12 or a group of battery cells 12, preferably on all sides and / or in particular such that the battery cell 12 and / or the group of battery cells 12 is mounted and / or arranged in a damped manner in the housing 9 via the insulating element 1A and / or 1B. In addition to an effective, in particular all-round, insulation, this also allows the battery cell 12 to be mounted in a robust and / or resistant manner, since any shocks and / or vibrations are damped and / or absorbed by the compressible insulating element 1A and / or 1B. In particular, the second insulating element 1B is laterally and / or vertically attached and / or longitudinally aligned on the inner side 13 of the housing lid 11 such that it is insertable between the battery cells 12, in particular when the housing lid 11 is placed on the lower housing part 10. The second insulating element 1B may optionally be attached and / or fastened laterally and / or longitudinally to the first insulating element 1A, for example by gluing, sewing or in any other manner. The battery 8 can have a plurality of second insulating elements 1B. Preferably, the second insulating elements 1B are arranged and / or provided between some of the battery cells 12, in particular between all of the battery cells 12. In Fig. 3, a battery 8 with several insulating elements 1B is illustrated diagrammatically.

[0036] As an alternative or in addition to the first insulating element 1A and / or the second insulating element 1B, the battery 8 may have a further and / or third insulating element 1C, for example as illustrated in Fig. 3. The third insulating element 1C is preferably arranged opposite the first insulating element 1A and / or at the underside and / or bottom of the housing interior 13, in particular at the inside 13 of the housing 9. Preferably, the underside and / or bottom is completely and / or over its entire surface covered by the third insulating element 1C.

[0037] In particular in addition to the first, second and / or third insulating elements 1A, 1B and / or 1C, a further and / or fourth insulating element 1D may also be provided. Preferably, the further and / or fourth insulating element 1D is provided and / or arranged on the inside and / or on one or more side walls of the housing 9. Preferably, the side walls are completely covered and / or thermally insulated by the fourth insulating element 1D. Preferably, in the cell 8 and / or housing 9, the woven fabric layer and / or fabric 21 - if present - is arranged on the side of the insulating element 1A, 1C, 1D facing towards the inside 13. Preferably, the insulating elements 1A, 1C, 1D are arranged on the inside 13 and / or inside the housing 9. The heat insulating elements 1A to 1D are preferably disposed between one battery cell 12 and / or multiple battery cells 12 and the housing 9, respectively. The battery cells 12 are preferably at least substantially completely and / or on all sides sealed and / or surrounded by one or more insulating elements 1A-1D. The battery 8 and / or the housing 9 may have an outlet 23 for the escape of gases. This is illustrated by way of example in FIG.

[0038] The outlet 23 is preferably provided in the housing lid 11 and / or on the front side of the battery 8 and / or the housing 9. Preferably, the outlet 23 is formed by an opening through the housing lid 11 and / or the insulating element 1A. The outlet 23 allows gas to escape from the housing 9, thus reducing the risk of explosion. The outlet 23 may have a filter 24 for the gas and / or a valve 25, in particular a one-way valve. By means of the valve it can be ensured that the gas can escape from the cell 8 but that the gas cannot enter the cell 8. Figures 4 and 5 show diagrammatically a test setup and / or test arrangement for carrying out temperature measurements on an insulating element 1 according to the present proposal.

[0039] In the carried out tests, the insulating function and / or insulating capacity of the proposed insulating element 1 was investigated. For this purpose, heat was specifically introduced into the housing 9 and / or corresponding structure via a heating element 16, preferably a heating foil, in order to simulate temperature conditions corresponding to the case of uncontrolled heating and / or thermal runaway. The obtained temperature diagrams and / or temperature curves are illustrated in Fig. 6 for the insulating element 1 with the first layer structure and in Fig. 7 for the insulating element 1 with the second layer structure.

[0040] In the test setup illustrated in FIG. 4, a heating element 16 was inserted between battery cell 12′—located in the second position starting from insulating element 1—and battery cell 12″—located in the third position starting from insulating element 1—and continuously heated to a temperature above 120° C., preferably above 200° C., to simulate uncontrolled heating and / or thermal runaway. At the same time, the resulting temperature curve and / or temperature rise of the insulating element 1 on the one hand, on the cold side 17 facing away from the heating element 16, and on the other hand, on the hot side 18 facing towards the heating element 16, were measured using measuring devices, in particular thermocouples, two measurements being performed for each layer structure. Curves M1 and M2 in FIG. 6 show the resulting temperature curves on the cold side 17 of an insulating element 1 with a first layer structure for each measurement, and curves M1 and M2 in FIG. 7 show the corresponding temperature curves for an insulating element 1 with a different and / or second layer structure. Generally, the test setup illustrated in FIG. 4 is intended to investigate and / or verify the insulation function with respect to inhibiting and / or retarding the transfer of thermal energy to adjacent battery cells 12 within the housing 9. The second test setup differs from the first one in that the temperature curve is determined with the insulation element 1 operating on the upper side with respect to the battery cell 12, as illustrated in Figure 5. This is intended to investigate and / or verify the insulation function and / or the insulation with respect to the interior space adjacent to the battery 8, in particular the vehicle cabin 15.

[0041] For this purpose, analogous to the first experimental setup, a heating element 16, in particular a heating foil, is arranged between adjacent battery cells 12 and heated to at least 120° C., preferably at least 200° C., in order to simulate uncontrolled heat generation and / or thermal runaway. The temperature course and / or temperature rise is recorded by means of measuring means, in particular thermocouples, on the one hand at the cold side 19 of the insulating element 1 remote from the heating element 16 and on the other hand at the hot side 20 of the insulating element 1 towards the heating element 16. Curve M3 in FIG. 6 illustrates the resulting temperature curve at the cold side 19 of the thermal insulation element 1 with the first layer structure, and curve M3 in FIG. 7 illustrates the resulting temperature curve for the second layer structure.

[0042] In the temperature diagram illustrated in FIG. 6, a thermal insulation element 1 was used with the following first layer structure: [Table 1] The X-axis represents the time course in minutes. The axis starts at "0", indicating the starting point for switching on the heating foil 16. The Y-axis represents temperature in °C. The curve begins just above 20 °C, which is essentially ambient temperature.

[0043] As already mentioned, a temperature below 120° C., in particular below 80° C., on the cold side 17 and / or 19 should be maintained for as long as possible in order to avoid damage and / or short circuits and / or to prevent complete destruction and / or explosion of the battery 8, in particular for a sufficiently long time to protect the passenger compartment 15 from the release of heat, gases and / or debris. The maximum temperature for all measurements was measured after about 30 minutes on curve M3 (i.e. on the cold side 19, FIG. 5) at 115.4° C. In this case the maximum temperature on the opposite hot side 20 was 837° C. In curve M1 (first measurement on the cold side 17, FIG. 4), a maximum temperature of 92.75° C. was reached after about 20 minutes. In this case, the maximum temperature on the opposite hot side 18 was 730° C. In curve M2 (second measurement on the cold side 17, FIG. 4), a maximum temperature of 89° C. was reached after about 20 minutes. In this case, the maximum temperature on the opposite hot side 18 was 728° C. Curves M1 and M2 only deviate slightly from each other - as would be expected - since they are two measurements of the same test series (test setup, FIG. 4).

[0044] A comparison of the one curve M3 (test setup, FIG. 5) with the other curves M1 and M2 (test setup, FIG. 4) first shows that the highest temperature (115.4° C.) is measured on the cold side 19. However, this temperature is only reached after more than 30 minutes - thus significantly later than in the case of the other curves M1 and M2. Until about 25 minutes after the heat is introduced, the curve M3 is clearly below the other two curves M1 and M2 and only rises from there. In this respect, especially in the first 20 to 25 minutes, an efficient insulation on the cold side 19 and therefore a high level of insulation for the interior and / or passenger compartment 15 adjacent to the front side is enabled.

[0045] In addition, the results show that the maximum limit temperature of 120° C. is not reached for all curves M1-M3, so that heat transfer and / or thermal runaway to adjacent battery cells 12 is efficiently delayed and / or suppressed, which eliminates or at least minimizes the risk of damage and / or short circuit. Furthermore, the first layer structure can be realized relatively cheaply.

[0046] Within the framework of the second temperature diagram illustrated in FIG. 7, the proposed thermal insulation element 1 was used with the following second layer structure: [Table 2] The X-axis represents the time course in minutes. The axis starts at "0" and initiates the starting point of switching on the heating foils 14 and / or 15 to initiate the heat development in the corresponding group of battery cells 12A-E (see FIG. 5). The Y-axis represents temperature in °C. The curve begins just above 20 °C, which is essentially ambient temperature. The maximum temperature for all measurements was determined after 10 minutes on curve M1 (i.e. the first measurement on the cold side 17, FIG. 4) to be 76.5° C. In this case the maximum temperature on the opposite hot side 18 was 1300° C. For curve M2, a maximum temperature of -75°C was reached on the cold side 17 after 35 minutes - in the second measurement according to Figure 4. In this case, the maximum temperature on the opposite hot side 20 was 1000°C. For curve M3, a maximum temperature of 70°C was reached on the cold side 19 after 55 minutes. In this case, the maximum temperature on the opposite hot side 20 was 730°C. As a result, even accelerated degradation of adjacent battery cells is avoided or at least reduced as a result of not reaching the preferred maximum limit temperature of 80° C. in all cases.

[0047] A comparison of one curve M3 (test setup, FIG. 5) with the other curves M1 and M2 (test setup, FIG. 4) shows that not only is there a minimum maximum temperature (70° C.) on the low-temperature side 19 (curve M3), but also that this maximum temperature occurs very late, after about 55 minutes. Nevertheless, a minimum temperature (730° C.) was also found on the corresponding high-temperature side 20. Furthermore, it can be seen from FIG. 7 that only one significant temperature increase in one of the curves M1-M3 was recorded after a time T of about 11-12 minutes.

[0048] The progression described in Figure 6 is also confirmed in that on the cold side 19, in particular in the first few minutes of heat input - up to about 45 minutes in Figure 7 - the temperature is significantly lower than on the cold side 17 (curves M1 and M2). In this respect, the insulating element 1 with the second layer structure allows a particularly effective thermal insulation of adjacent interiors and / or areas, in particular the vehicle compartment 15.

[0049] A comparison of the curves M1-M3 in Fig. 7 (second layer structure) with the corresponding curves in Fig. 6 (first layer structure) also shows that a further improved thermal insulation function can be achieved with the second layer structure. In particular, a reduction in the maximum temperature is achieved, the difference in curve M3 (first layer structure: 115.4°C compared to second layer structure: 70.0°C) being particularly striking. This proves a particularly advantageous use of the second layer structure as front insulation. All in all, due to the multi-layer structure of the intermediate material 4, in particular with the polyimide layer arranged inside as intermediate layer 6, the second layer structure allows an optimal reduction of heat transfer and therefore a particularly efficient thermal insulation function. The polyimide layer protected by the nonwoven fabric retains its structure even after thermal explosion, so that electrical insulation is maintained.

[0050] Overall, the tests show that the proposed thermal insulation element 1 is suitable both for thermal containment within the battery 8 and for topside arrangement and / or insulation, i.e. in particular for thermal protection of the adjacent vehicle compartment 15. Efficiency is optimal with the second layered composite, while the first layered composite allows a relatively low-cost implementation with an equally effective thermal insulation function. The invention also relates to the use of the proposed thermal insulation element 1 on and / or in a battery 8, preferably a lithium-ion battery, in particular a traction battery for electric vehicles. In particular, a thermal insulation element 1 is placed on the front side of the housing 9 to provide thermal insulation at the front side. Alternatively or additionally, a thermal insulation element 1 for thermal insulation is arranged between two adjacent battery cells 12 . In particular, the insulating element 1 is attached and / or fixed to the housing lid 11 and / or to the top of the housing 9, preferably by adhesive. Particularly preferably, the insulating element 1 is mounted, in particular over its entire surface, on the inside 13 of the housing lid 11 facing towards the housing interior. Preferably, the insulating elements 1 are mounted and / or aligned laterally and / or vertically on the inner side 13 . In particular, at least one first insulating element 1A and at least one second insulating element 1B are used, with the first insulating element 1A closing and / or thermally insulating the housing interior at the front, and the second insulating element 1B being positioned between adjacent battery cells 12A-E. Preferably, the second insulating element 1B is attached to the first insulating element 1A, in particular laterally and / or longitudinally, preferably by glued, pierced or welded. The individual aspects of the invention, as mentioned above, can be combined as desired, but can also be realized independently of one another. [Explanation of symbols]

[0051] 1. Thermal insulation elements 1A (First) Insulation Element 1B (Second) Insulation Element 1C (Third) Insulation Element 1D (4th) Insulation Element 2 First coating layer 3 Second coating layer 4 Intermediate materials 5 Fiber layer 6. Middle Tier 7 Adhesive layer 8 batteries 9. Housing 10 Lower housing part 11 Housing lid / upper housing part 12, 12', 12" Battery Cells 13 Inside 14 Vehicles 15 Cabin 16 Heating element 17 Cold side vertical surface 18 High temperature side vertical surface 19 Low temperature side horizontal plane (above the battery) 20 High temperature side horizontal plane (above the battery) 21 Woven fabric 22 Additional layers 23 Exit 24 Filters 25 Valves M curve T Time X-axis Y-Axis

Claims

1. A first coating layer (2); A second coating layer (3); and a compressible and / or flexible intermediate material (4) arranged between said covering layers (2, 3), comprising at least one heat-resistant fiber layer (5); A multilayer insulating element (1) for the thermal insulation of a battery (8), comprising: the fibrous layer (5) is formed from a needled nonwoven fabric, and / or The covering layers (2, 3) are weak in bending, and the insulating element (1) as a whole is compressible and flexible. A multi-layer insulation element, characterized in that

2. 2. A thermal insulation element according to claim 1, characterized in that the fibre layer (5) is made from glass fibres or silicate fibres or a mixture thereof.

3. An insulating element according to claim 1 or 2, characterised in that the fibres of the fibre layer (5) have a length of more than 30 mm, preferably more than 40 mm, in particular substantially between 50 mm and 60 mm.

4. An insulating element according to any one of claims 1 to 3, characterized in that the fibres have an average diameter of at least 4 μm, preferably at least 5 μm, in particular between 6 μm and 15 μm.

5. Thermal insulation element according to any one of the preceding claims, characterized in that the fibre layer (5) is binder-free and / or free of molten beads.

6. 6. The insulating element according to claim 1, wherein the intermediate material (4) has a multi-layer structure comprising at least two fibrous layers (5) separated from each other by a heat-resistant, highly dielectric and / or weak-bending intermediate layer (6).

7. 7. The thermal insulation element according to claim 6, characterized in that the intermediate layer (6) is configured as a heat-resistant and / or heat-reflecting metal layer, preferably an aluminum layer, in particular an aluminum foil.

8. 7. The thermal insulation element according to claim 6, characterized in that the intermediate layer (6) is constructed as a heat-resistant and / or highly dielectric plastic layer, preferably a polyimide layer, in particular a polyimide film.

9. 9. The insulating element according to claim 1, wherein at least one covering layer (2, 3) is designed to be impermeable to water vapor, preferably airtight and / or water-repellent and / or waterproof.

10. An insulating element according to any one of the preceding claims, characterized in that the covering layers (2, 3) are less than 1 mm, preferably less than 0.5 mm, in particular less than 0.1 mm thick.

11. Thermal insulation element according to any one of the preceding claims, characterized in that at least one covering layer (2, 3) is formed as a heat-resistant metal layer, preferably an aluminum foil.

12. Thermal insulation element according to any one of the preceding claims, characterized in that at least one covering layer (2, 3) is formed as a heat-resistant plastic layer, preferably a polyimide film.

13. 13. Thermal insulation element according to any one of the preceding claims, characterized in that at least one covering layer (2, 3) is formed as a heat-resistant fabric layer, preferably a glass fabric foil.

14. 14. The thermal insulation element according to claim 1, characterized in that at least one covering layer (2, 3), in particular both covering layers (2, 3), are designed as a heat-resistant mica layer, preferably as a mica paper layer or mica plate.

15. Thermal insulation element according to any one of the preceding claims, characterized in that at least one covering layer (2, 3) or additional layer (21) is formed by a woven fabric (21).

16. 16. The insulating element according to claim 15, characterized in that the woven fabric (21) is a metal mesh, in particular a wire mesh made of stainless steel and / or aluminium, and / or comprises metal fibres, in particular stainless steel fibres and / or aluminium fibres.

17. 17. Thermal insulation element according to claim 15 or 16, characterized in that the woven fabric (21) is a glass fibre fabric and / or contains glass fibres.

18. Thermal insulation element according to any one of claims 15 to 17, characterized in that the woven fabric (21) is a carbon fibre fabric and / or comprises carbon fibres.

19. Thermal insulation element according to any one of claims 15 to 18, characterized in that the woven fabric (21) is a silicate fabric and / or comprises silicate fibres.

20. 20. The thermal insulation element according to any one of the preceding claims, characterized in that the first covering layer (2) is designed as a mica layer, preferably as a mica paper layer, and the second covering layer (3) is designed as an aluminum layer, preferably as an aluminum foil.

21. 20. The thermal insulation element according to any one of claims 1 to 19, characterized in that the first covering layer (2) is formed as a mica layer, preferably as a mica paper layer or mica plate, and the second covering layer (3) is formed as a polyimide layer, preferably as a polyimide film.

22. 20. The insulating element according to any one of the preceding claims, characterized in that the first covering layer (2) is formed as a woven fabric (21), preferably a metal mesh, a glass fiber fabric, a carbon fiber fabric or a silicate fabric, and the second covering layer (3) is formed as an aluminum layer, preferably an aluminum foil.

23. 20. The insulation element according to any one of claims 1 to 19, characterized in that the first covering layer (2) is formed as a woven fabric (21), preferably a metal mesh, a glass fiber fabric, a carbon fiber fabric or a silicate fabric, and the second covering layer (3) is formed as a polyimide layer, preferably a polyimide film.

24. 20. The thermal insulation element according to any one of claims 1 to 19, characterized in that the first covering layer (2, 3) is formed as a heat-resistant mica layer, preferably as a mica paper layer or mica plate, and the second covering layer (3) is formed as a woven fabric (21), preferably as a metal mesh, a glass fiber fabric, a carbon fiber fabric, a silicate fabric or a blended fabric.

25. 25. An insulating element according to any one of the preceding claims, characterized in that the insulating element (1) comprises, in addition to the covering layers (2, 3), an additional layer (22) of woven fabric (21), preferably of metal mesh, glass fiber fabric, carbon fiber fabric, silicate fabric or blended fabric.

26. 26. An insulating element according to claim 25, characterized in that the additional layer (22) is arranged on the outside of the insulating element (1).

27. Thermal insulation element according to any one of the preceding claims, characterized in that the covering layers (2, 3) and the intermediate material (4) are connected to one another by means of an adhesive bond.

28. 28. An insulating element according to any one of the preceding claims, characterised in that at least one of the covering layers (2, 3) and / or the intermediate layer (6) has a dielectric strength of more than 1 kV / mm, preferably more than 1.5 kV / mm, in particular more than 2 kV / mm.

29. The heat insulating element (1) has a thickness of 1500 g / m 2 less than 1300 g / m 2 Less than 1000 g / m 2 An insulating element according to any one of the preceding claims, characterized in that it has a mass per unit area of ​​less than 1000 mm.

30. The fiber layer (5) and / or the intermediate material (4) have a fiber density of 1000 g / m 2 less than 800 g / m 2 Less than 600 g / m 2 An insulating element according to any one of the preceding claims, characterized in that it has a mass per unit area of ​​less than 1000 mm.

31. The insulation element (1) and / or the fibrous layer (5) have a thickness of 150 g / m 2 More than 200 g / m 2 More preferably 300 or 400 g / m 2 An insulating element according to any one of the preceding claims, characterized in that it has a mass per unit area of ​​more than 1000 .mu.m.

32. An insulating element according to any one of the preceding claims, characterized in that the insulating element (1) has a thickness of less than 7 mm, preferably less than 6 mm, in particular between 2 and 3 mm.

33. An insulating element according to any one of the preceding claims, characterized in that the insulating element (1) has a dielectric strength of more than 20 kV / mm, preferably more than 30 kV / mm, in particular 40-70 kV / mm.

34. An insulating element according to any one of the preceding claims, characterized in that the insulating element (1) is at least in places sticky or has an adhesive layer (7) on at least one flat side.

35. A housing (9); At least one multi-layer insulation element (1) arranged in and / or on said housing (9) for thermal insulation and fire protection; A battery (8), preferably a lithium-ion battery, in particular a traction battery for an electric vehicle, comprising: Battery, characterized in that the thermal insulation element (1) is designed according to any one of claims 1 to 34.

36. 36. The battery according to claim 35, characterized in that the heat insulating element (1) overlaps or covers and / or thermally insulates and / or thermally insulates the battery (8), the housing (9), the housing lid (11) and / or the battery cells (12) at least partially, preferably completely and / or over the entire surface at the front.

37. 37. Battery according to claim 35 or 36, characterized in that the heat insulating element (1) is attached and / or fixed, preferably glued, to a housing lid (11) and / or a housing top of the housing (9).

38. 38. Battery according to claim 36 or 37, characterized in that the insulating element (1) is attached to the housing lid (11) and / or to the inside (13) of the housing (9), on the inside (13) facing the inside of the housing, in particular over its entire surface.

39. Battery according to any one of claims 35 to 38, characterized in that the thermal insulation element (1) for thermal insulation is arranged between two adjacent battery cells (12) of the battery (8).

40. Battery according to any one of claims 35 to 39, characterized in that the heat insulating element (1) is provided and / or arranged under the interior space and / or at the base of the inside (13) of the housing (9), in particular over the entire surface.

41. The battery according to any one of claims 35 to 40, characterized in that at least one first insulating element (1A) and at least one second insulating element (1B) are provided, the first insulating element (1A) closing and / or thermally insulating the housing interior at the front, and the second insulating element (1B) being arranged between adjacent battery cells (12).

42. 42. The battery according to claim 41, characterized in that the second insulating element (1B) is attached in a thermally insulating manner to the first insulating element (1A), preferably laterally and / or longitudinally, preferably by glued, sewn or welded.

43. The battery according to any one of claims 35 to 42, characterized in that a plurality of heat insulating elements (1B) are provided, each arranged between adjacent battery cells (12), in particular between all battery cells (12).

44. Battery according to any one of claims 35 to 43, characterized in that at least one first insulating element (1A) and at least one further and / or third insulating element (1C) are provided, the first insulating element (1A) being arranged on the upper side of the interior of the housing (9) and / or on the housing lid (11) of the housing (9) and the further and / or third insulating element (1C) being provided and / or arranged on the lower side of the interior space and / or on the bottom of the inner side (13) of the housing (9).

45. Battery according to any one of claims 35 to 44, characterized in that at least one first insulating element (1A) and at least one further and / or fourth insulating element (1D) are provided, the first insulating element (1A) being provided on the upper side of the interior space (13) of the housing and / or on a housing lid (11) of the housing (9) and the further and / or fourth insulating element (1D) being provided and / or arranged on the inside (13) and / or on one or more side walls of the housing (9).

46. Battery according to any one of claims 35 to 45, characterised in that the battery cells (12) of the battery (8) are at least substantially completely and / or on all sides sealed or surrounded by one or more thermal insulation elements (1, 1A, 1B, 1C, 1D).

47. A battery according to any one of claims 35 to 46, characterised in that the battery (8) and / or the housing (9) have an outlet (22) for the escape of gases.

48. 48. The battery according to claim 47, characterized in that the outlet (22) comprises a filter (23) and / or a valve (24).

49. Use of a multilayer insulating element (1) for the thermal insulation of a battery (8), comprising:

34. Use, characterized in that a multi-layer and generally flexible and compressible insulating element (1) according to any one of claims 1 to 33, comprising a long-fiber needled nonwoven fabric as a fiber layer (5) and / or arranged between and / or above adjacent battery cells (12) for thermal insulation.

Images