Isolated channel system

Abstract

An isolated aisle system in an electric motor vehicle comprises an aisle connecting a first area (9) to a second area (10), where the first area (9) is air-permeable in a direction towards a battery of the motor vehicle, and where the second area (10) is air-permeable in a direction towards a passenger cabin of the motor vehicle. The system further comprises a barrier element (2) comprising an expanded material (3 '), where the expanded material (3') closes a channel towards the first region (9), and where the expanded material (3 ') is a one-component heat-curable epoxy resin composition.

Description

[0001] The present invention relates to an isolated A channel system and in particular a system for isolating a channel in an electric motor vehicle.

[0002] In electric motor vehicles, in addition to the usual sound insulation, there is the problem that the interior of the motor vehicle must be protected against a failure of the drive battery. If the battery of an electric motor vehicle thermally runs away or overheats in an exothermic chemical reaction, toxic and very hot gases are produced. These toxic and hot gases must be kept away from the passenger compartment of the motor vehicle for a certain minimum time in order to ensure that the passengers in the motor vehicle can be brought to safety in time.

[0003] One object of the present invention is therefore to provide a device that allows the hot, toxic gases produced during thermal runaway of a battery of an electric motor vehicle to be kept away from the passenger compartment.

[0004] This object is achieved by an insulating channel system in an electric motor vehicle, the system comprising: a channel connecting a first area to a second area, wherein the first area is air-permeable in a direction toward a battery of the motor vehicle, and wherein the second area is air-permeable in a direction toward a passenger compartment of the motor vehicle; and an insulating element, which comprises an expanding material, wherein the expanding material closes the channel toward the first area; wherein the expanding material is a foamed and at least partially cured epoxy resin composition.

[0005] This solution has the advantage that known materials can be used in automobile construction for this new purpose. Epoxy-based compositions that expand in this way under the action of heat are usually used to reinforce vehicle body parts. These materials have a very high mechanical load capacity in the expanded and cured state. Usually, these materials are referred to as reinforcing adhesives or "expanded reinforcements", "reinforced foams", "reinforcement materials" or "expanded adhesives".

[0006] Therefore, one advantage of the solution proposed here is that already proven and known materials can be used to solve the tasks proposed at the beginning. For example, such materials do not have to be re-licensed to the car manufacturer, which can save costs and complexity.

[0007] The solution proposed here also offers the advantage that, by using expandable materials, a simple and effective insulation of the channel can be achieved. Such an insulation element proposed here can be assembled in the vehicle body in a non-expanded state and then expanded and cured in an oven during painting of the vehicle body. The handling, installation and planning of such an insulation element are therefore simple and cost-effective.

[0008] The term "isolating element" or "isolating" or "isolating" is intended to include an element or structure or method step that is used to shield and / or seal and / or isolate passages associated with the present invention. In this case, the different characteristics of this isolating element may occur alone or in combination with one another.

[0009] In one exemplary embodiment, the channel is configured in a tube-like manner.

[0010] In one exemplary embodiment, the channel is formed by side walls surrounding the cavity.

[0011] In another embodiment, the channel is configured as a hole. In this case, the channel is particularly formed by an opening in the wall.

[0012] In an exemplary embodiment, the insulation element is only exposed to expanded material in the direction towards the first region.

[0013] This arrangement of intumescent material provides the advantage that the epoxy resin composition cured thereby forms an effective protective shield against the toxic and hot gases from a battery that is running away. It has been found in experiments that many other materials cannot withstand such a load for a long enough time. It is therefore advantageous if only this durable intumescent material is exposed to the hot gases without other parts of the insulating element (such as carrier segments or the like).

[0014] In an exemplary embodiment, the layer thickness of the expanded material measured in the direction along the main channel axis of the channel is 1-50 mm. Preferably, the layer thickness is 2-30 mm, particularly preferably 5-20 mm.

[0015] It has been found in experiments that a certain layer thickness is required to withstand the hot gas load for a sufficiently long time. In experiments, the uppermost layer of the cured epoxy resin composition carbonized during the hot gas load, but the lower layer of the cured epoxy resin composition remained intact. Therefore, a sufficiently thick layer must be provided to be able to withstand the hot gas load for a sufficiently long time.

[0016] In an exemplary embodiment, the expanded material before expansion, i.e. the expandable material, has a layer thickness measured in the direction along the main channel axis of the channel of between 1 mm and 10 mm. The layer thickness is preferably between 2 mm and 7 mm, particularly preferably between 3 mm and 6 mm.

[0017] In an exemplary embodiment, the isolation element further comprises a carrier.

[0018] The provision of a carrier offers the advantage that the expansion material before expansion can be positioned more easily and precisely in the motor vehicle.

[0019] In an exemplary development, the carrier is configured in the form of a foil. In particular, the carrier is configured in a flexible manner. In another exemplary embodiment, the carrier can be made of metal.

[0020] In an alternative embodiment, the carrier is configured in the form of a rigid carrier, wherein the carrier is made in particular of plastic.

[0021] In an exemplary further development, the carrier and the expansion material are produced by a two-component injection molding process.

[0022] In an exemplary embodiment, the isolation element does not comprise a carrier.

[0023] This offers the advantage that the spacer element can thereby be produced in a more cost-effective manner, for example by an extrusion process.

[0024] In an exemplary further development, the spacer element is fixed to the structure of the channel by means of an adhesive film.

[0025] This has the advantage that the expandable material can be positioned in the region of the channel before expansion.

[0026] In a further exemplary further development, the insulating element is fixed to the structure of the channel by means of push pins.

[0027] This method also offers the advantage that the expandable material can be pre-fixed at the desired position in the channel region before expansion without any carrier.

[0028] In one exemplary embodiment, the system is in a motor vehicle without an internal combustion engine.

[0029] In an alternative embodiment, the system is in a motor vehicle with an electric drive and an internal combustion engine (in particular in a hybrid vehicle).

[0030] In the context of the present invention, the term “battery of a motor vehicle” is intended to be understood as a battery for supplying energy to an electric drive. It is not intended to be understood as a battery for starting an internal combustion engine.

[0031] Expanded material

[0032] In the state of use, that is, in the system of separating passages present in a finished vehicle, the initially expandable material is in the form of an expanded material. However, certain properties of this expanded material can be better described in terms of the state before expansion. Therefore, in the following more detailed description of this material, in some places reference is made to the expanded material after expansion and in some places to the expandable material before expansion.

[0033] In an exemplary embodiment, the expanded material has a volume that is 50% to 1200% greater than before expansion. In a preferred further development, the volume increases by 100% to 1000%, preferably by 200% to 800%.

[0034] In an exemplary embodiment, the expanded material is a foamed and cured epoxy composition.

[0035] In one exemplary embodiment, the expanded material is obtained from a one-component heat-curing epoxy resin composition.

[0036] In an exemplary embodiment, the expanded material (3') before expansion is in the form of an expandable material (3) having the following composition:

[0037] A one-component heat-curing epoxy resin composition comprising:

[0038] a) at least one epoxy resin A having an average of more than one epoxy group per molecule;

[0039] b) at least one latent curing agent for the epoxy resin; and

[0040] c) at least one physical or chemical blowing agent BA.

[0041] In an exemplary embodiment, the proportion of epoxy resin A having an average of more than one epoxy group per molecule is 30 to 90 wt %, 35 to 85 wt %, 40 to 75 wt %, more preferably 45 to 60 wt %, relative to the total weight of the heat-curable one-component epoxy resin composition.

[0042] In an exemplary embodiment, epoxy resin A is a solid epoxy resin.

[0043] In an exemplary embodiment, the heat-curable one-component epoxy resin composition further comprises:

[0044] d) at least one toughness improver D.

[0045] In an exemplary embodiment, the toughness improver D is selected from the group consisting of a terminal blocked polyurethane polymer D1, a liquid rubber D2, and a core / shell polymer D3.

[0046] In an exemplary embodiment, the latent curing agent is selected from dicyandiamide, guanamine, guanidine, aminoguanidine and its derivatives, substituted urea, imidazole and amino complex, preferably dicyandiamide.

[0047] In an exemplary embodiment, the heat-curable one-component epoxy resin composition further comprises at least one filler F selected from calcium carbonate, calcium oxide, talc, glass fiber and pyrogenic silicic acid, more preferably talc, glass fiber and pyrogenic silicic acid.

[0048] In an exemplary embodiment, the heat-curable one-component epoxy resin composition further comprises at least one flame retardant component G. In particular, the flame retardant component G is selected from ammonium phosphate, ammonium pyrophosphate, ammonium polyphosphate, melamine phosphate, magnesium sulfate and boric acid, preferably ammonium polyphosphate.

[0049] Preferably, the particle size of the ammonium polyphosphate is ≤100 μm, in particular 50 μm to 5 μm.

[0050] The total proportion of the flame retardant component G is advantageously 3 to 50% by weight, preferably 5 to 40% by weight, 8 to 35% by weight, relative to the total weight of the epoxy resin composition.

[0051] It is further advantageous if the ammonium polyphosphate is an ammonium polyphosphate having the formula (NH4PO3)n, wherein n is 200-2000, preferably 600-1500.

[0052] In an exemplary embodiment, the proportion of the blowing agent BA is 0.1% to 10% by weight, preferably 0.5% to 5% by weight, in particular 1% to 3% by weight, relative to the total weight of the epoxy resin composition.

[0053] The epoxy resin composition is one-component, which means that the components of the epoxy resin composition, in particular the epoxy resin and the curing agent, are present in one component without curing at normal ambient or room temperature. It can therefore be handled in this form, whereas in the case of a two-component system the components can be mixed directly before use.

[0054] Curing of the one-component epoxy resin composition is carried out by heating, typically at a temperature greater than 70°C, for example in the range of 100 to 220°C.

[0055] In expressions such as polyol or polyisocyanate, the prefix "poly" means that the compound has two or more of the groups in question. A polyisocyanate is, for example, a compound having two or more isocyanate groups.

[0056] The expression "independently of one another" used hereinafter means that in the same molecule, two or more identically designated substituents may have the same or different meanings according to definition.

[0057] The dashed lines in the formulae herein each represent a bond between the relevant substituent and the corresponding molecular residue.

[0058] Unless otherwise stated, room temperature herein refers to a temperature of 23°C.

[0059] The heat-curable one-component epoxy resin composition contains at least one epoxy resin A which has on average more than one epoxy group per molecule. The epoxy groups are preferably in the form of glycidyl ether groups.

[0060] The proportion of epoxy resin A having on average more than one epoxide group per molecule, relative to the total weight of the heat-curable one-component epoxy resin composition, is preferably 30% to 90% by weight, 35% to 85% by weight, 40% to 75% by weight, particularly preferably 45% to 60% by weight.

[0061] The epoxy resin A having an average of more than one epoxy group per molecule is preferably a liquid epoxy resin or a solid epoxy resin, particularly preferably a solid epoxy resin. The term "solid epoxy resin" is very familiar to technicians in the field of epoxides and is used in contrast to "liquid epoxy resins". The glass transition temperature of solid resins is higher than ambient temperature, so that they can be crushed at room temperature to form pourable powders. Preferably, more than 70% by weight, particularly preferably more than 80% by weight, more than 90% by weight, more than 95% by weight, more than 98% by weight of epoxy resin A is a solid epoxy resin.

[0062] Preferred epoxy resins have the formula (II)

[0063]

[0064] In this formula, the substituents R' and R" independently of one another represent H or CH3.

[0065] In solid epoxy resins, the index s has values ​​>1.5, in particular from 2 to 12.

[0066] Such solid epoxy resins are commercially available, for example from Dow or Huntsman or Hexion.

[0067] Compounds of formula (II) with an index s of 1 to 1.5 are referred to by those skilled in the art as semisolid epoxy resins. They are also considered solid resins in the context of the present invention. However, preferred solid epoxy resins are epoxy resins in the narrow sense, that is to say, in which the index s has a value greater than 1.5.

[0068] In liquid epoxy resins, the index s has a value less than 1. Preferably, s has a value less than 0.2.

[0069] Thus, diglycidyl ether of bisphenol A (DGEBA), diglycidyl ether of bisphenol F and diglycidyl ether of bisphenol A / F are preferred. Liquid resins of this type can be used, for example, as GY 250, PY 304, GY 282 (Huntsman) or DER TM 331 or DER TM 330 (Dow) or Epikote 828 (Hexion).

[0070] The epoxy resin A is preferably a solid epoxy resin having the formula (II).

[0071] The heat-curable one-component epoxy resin composition also contains at least one latent curing agent for epoxy resin. The latent curing agent is substantially inert at room temperature and is activated by elevated temperature (usually at 70° C. or higher), thereby initiating a curing reaction. Conventional latent curing agents for epoxy resins can be used. Preferred are nitrogen-containing latent epoxy resin curing agents.

[0072] The latent curing agent is preferably selected from dicyandiamide, guanamine, guanidine, aminoguanidine and its derivatives, substituted ureas, imidazoles and amine complexes, preferably dicyandiamide.

[0073] The latent curing agent is preferably used in a stoichiometric amount relative to the epoxy groups in the composition. The molar ratio of epoxy groups to active hydrogen of the latent curing agent is preferably 0.8-1.2, particularly 0.9-1.1, preferably 0.95-1.05.

[0074] The proportion of the latent curing agent is preferably 0.1 to 15% by weight, particularly preferably 0.2 to 5% by weight and in particular 0.5 to 3% by weight, relative to the total weight of the epoxy resin composition.

[0075] The heat-curable one-component epoxy resin composition optionally contains at least one toughness improver D. The toughness improver D can be solid or liquid. In particular, the toughness improver D is selected from the group consisting of a terminal-blocked polyurethane polymer D1, a liquid rubber D2, and a core / shell polymer D3.

[0076] The proportion of toughness improver D is preferably 5 to 30% by weight, particularly preferably 7.5 to 20% by weight, relative to the total weight of the epoxy resin composition.

[0077] In a preferred embodiment, the heat-curable one-component epoxy resin composition further comprises at least one filler F. Here, the filler is preferably mica, talc, kaolin, wollastonite, feldspar, syenite, chlorite, bentonite, montmorillonite, calcium carbonate (precipitated or ground), dolomite, quartz, silicic acid (fumed or precipitated), cristobalite, calcium oxide, aluminum hydroxide, magnesium oxide, ceramic hollow beads, glass hollow beads, organic hollow beads, glass beads, glass fibers and color pigments. Particularly preferably, the filler is selected from calcium carbonate, calcium oxide, talc, glass fibers and pyrogenic silicic acid, more preferably talc, glass fibers and pyrogenic silicic acid.

[0078] The total proportion of the entire filler F is advantageously 3 to 50% by weight, preferably 5 to 40% by weight, 8 to 35% by weight, relative to the total weight of the epoxy resin composition.

[0079] The heat-curable one-component epoxy resin composition comprises at least one physical or chemical blowing agent BA.

[0080] Chemical foaming agents are organic or inorganic substances that form or crack gaseous substances under the influence of temperature, moisture, electromagnetic radiation or chemical substances. Such substances are particularly azodicarbonamide, sulfonyl hydrazide, bicarbonate or carbonate. For example, compounds that transform into a gaseous aggregate state under temperature, pressure or volume changes, particularly under elevated temperature, and therefore form a foam structure due to volume expansion can be used as physical foaming agents. Such physical foaming agents are particularly liquids that evaporate at elevated temperatures. In addition, gases or low-boiling liquids introduced into the composition in the form of microcapsules can be used as physical foaming agents. Both chemical and physical foaming agents can produce foam structures in polymer compositions.

[0081] The at least one physical or chemical blowing agent BA preferably has an activation temperature of 120°C to 220°C, preferably 140°C to 200°C.

[0082] The proportion of the blowing agent BA is advantageously 0.1% to 10% by weight, preferably 0.5% to 5% by weight and in particular 1% to 3% by weight, relative to the total weight of the epoxy resin composition.

[0083] Particularly preferred heat-curable one-component epoxy resin compositions comprise:

[0084] 30% to 90% by weight, 35% to 85% by weight, 40% to 75% by weight, particularly preferably 45% to 60% by weight, relative to the total weight of the heat-curable epoxy resin composition, of at least one epoxy resin A having on average more than one epoxy group per molecule;

[0085] 0.1% to 15% by weight, particularly preferably 0.2% to 5% by weight, in particular 0.5% to 3% by weight, relative to the total weight of the heat-curable epoxy resin composition, of at least one latent curing agent for epoxy resins, more particularly dicyandiamide;

[0086] 0.1% to 10% by weight, preferably 0.5% to 5% by weight, in particular 1% to 3% by weight, of a blowing agent BA, relative to the total weight of the heat-curable epoxy resin composition;

[0087] - preferably 5% to 30% by weight, preferably 7.5% to 20% by weight, relative to the total weight of the heat-curable epoxy resin composition, of at least one toughness improver D;

[0088] - preferably 5 to 40% by weight, preferably 20 to 40% by weight, of a filler F selected from calcium carbonate, calcium oxide, talc, glass fibers and pyrogenic silicic acid, more preferably talc, glass fibers and pyrogenic silicic acid, relative to the total weight of the heat-curable epoxy resin composition;

[0089] - Optionally, 3% to 50% by weight, preferably 5% to 40% by weight, in particular 8% to 35% by weight, based on the total weight of the heat-curable epoxy resin composition, of at least one flame retardant component G selected from ammonium phosphate, ammonium pyrophosphate, ammonium polyphosphate, melamine phosphate, magnesium sulfate and boric acid, preferably ammonium polyphosphate.

[0090] Furthermore, the preferred heat-curable one-component epoxy resin composition can advantageously consist of more than 80% by weight, preferably more than 90% by weight, in particular more than 95% by weight, particularly preferably more than 98% by weight of the above-mentioned components, relative to the total weight of the epoxy resin composition.

[0091] Details and advantages of the invention are described below with reference to exemplary embodiments and schematic drawings, in which:

[0092] Figure 1 A schematic diagram of the channel is shown;

[0093] Figure 2 a schematic diagram showing a channel in which an isolation element is arranged; and

[0094] Figures 3a to 6b A schematic diagram of an isolated channel system is shown.

[0095] Figure 1 By way of example, a channel 5 in an electric motor vehicle is shown. In this case, the channel 5 connects a first region 9 with a second region 10. The first region 9 is permeable to air in the direction of the battery of the motor vehicle, and the second region 10 is permeable to air in the direction of the passenger compartment of the motor vehicle. In this exemplary embodiment, the channel 5 is configured as a duct-like channel, in which the side walls 6 surround the cavity. Furthermore, arrows indicate the direction in which hot and toxic gases propagate in the event of a thermal runaway of the battery of the motor vehicle.

[0096] Figure 2 Again, the channel 5 in the electric motor vehicle is shown. However, Figure 2The channel 5 is now separated by the separating element 2. The separating element 2 thus prevents the hot and toxic gases from being able to diffuse from the first region 9 to the second region 10. This is shown in the figure by the dashed lines and crossed-out arrows.

[0097] Exemplary and possible embodiments of such an insulating element 2 are now schematically and incompletely shown in the following figures. In this case, for each exemplary embodiment, the state of the system 1 before the expansion of the expandable material 3 and the state after the expansion of the expandable material 3 are shown. The system 1 after expansion, i.e. with the expanded material 3', is each denoted as system 1'.

[0098] Figure 3a and 3b A first exemplary system 1 or 1 ' is shown in FIG. 1 . In this exemplary embodiment, the channel 5 is again configured in a tubular manner and has side walls 6. In this case, the insulating element 2 is positioned in the channel in such a way that the expanded material 3' closes the channel. In this case, the expanded material is oriented toward the first region 9. In this exemplary embodiment, the insulating element 2 comprises an expandable material 3 or an expanded material 3' and a carrier 4. In this exemplary embodiment, the carrier 4 also has a clamp, which simplifies positioning in the region of the channel.

[0099] exist Figure 3a In FIG. 5 , a main channel direction 11 through the channel 5 is shown. In the exemplary embodiment, the main channel direction 11 extends essentially parallel to the side wall 6.

[0100] Figure 4a and 4b Another example of a system 1 or 1' of isolating channels is shown in FIG. Figure 3a and 3b Unlike the exemplary embodiment of , the carrier 4 and the expandable material 3 do not form a continuous surface on the side of the first region 9 before the material expands. However, Figure 4b It is shown that in the use state of the system 1', the expanded material 3' completely closes the channel 5 in the direction of the first region 9. The insulating effect of the insulating element 2 against hot and toxic gases is thus fully achieved.

[0101] Figure 5a and 5b The insulating element 2 is shown without a carrier. The insulating element 2 in this exemplary embodiment is fixed to the structure in the region of the channel 5 by means of an adhesive layer. The expanded material 3' completely closes the channel 5 again in the use state of the system 1'.

[0102] at last, Figure 6a and 6bA further exemplary embodiment of a system 1 or 1 ′ is shown. In this exemplary embodiment, the channel 5 is configured in a hole-like manner, wherein the channel 5 is formed by an opening 8 in a wall 7. In this exemplary embodiment, the main channel direction 11 extends substantially perpendicularly to the wall 7.

[0103] Here, the thermal insulation element 2 also comprises a carrier 4 and an expandable material 3 or an expanded material 3'. After the expandable material 3 has expanded, the expanded material closes the channel 5 towards the first region 9, such as Figure 6b shown.

[0104] Reference numerals list

[0105] 1 System (before using the state)

[0106] 1' System (in use)

[0107] 2 Isolation components

[0108] 3 Expandable materials

[0109] 3' Expanded material

[0110] 4 Carrier

[0111] 5 channels

[0112] 6 Sidewall

[0113] 7 walls

[0114] 8 Opening

[0115] 9. Area 1

[0116] 10 Second Area

[0117] 11 Main channel axis

Claims

1. A system (1') of isolated passages (5) in an electric motor vehicle, said system (1') comprising: a channel (5) connecting a first region (9) to a second region (10), wherein the first region (9) is permeable to air in the direction towards a battery of the motor vehicle, and wherein the second region (10) is permeable to air in the direction towards a passenger compartment of the motor vehicle; as well as an insulating element (2) comprising an expanded material (3'), wherein the expanded material (3') closes the channel (5) towards the first region (9); The expanded material (3') is a foamed and at least partially cured epoxy resin composition.

2. The system (1') according to claim 1, wherein the channel (5) is configured in a duct-like form and / or wherein the channel (5) is formed by side walls (6) surrounding a cavity.

3. The system (1') according to claim 1, wherein the channel (5) is configured in the form of a hole and / or wherein the channel (5) is formed by an opening (8) in a wall (7).

4. The system (1') as claimed in any one of the preceding claims, wherein the insulation element (2) is exposed only to expanded material (3') in the direction towards the first region (9).

5. The system (1') according to any of the preceding claims, wherein the expanded material (3') has a layer thickness measured in a direction along a main channel axis (11) of the channel (5) of between 1 mm and 50 mm.

6. The system (1') according to any one of the preceding claims, wherein the expanded material (3') has a volume that is 50% to 1200% greater than before expansion.

7. The system (1') according to any one of the preceding claims, wherein the expanded material (3') before expansion is in the form of an expandable material (3) having the following composition: A one-component heat-curing epoxy resin composition comprising: a) at least one epoxy resin A having an average of more than one epoxy group per molecule; b) at least one latent curing agent for the epoxy resin; and c) at least one physical or chemical blowing agent BA.

8. The system (1') according to any one of the preceding claims, wherein the isolation element (2) comprises a carrier (4).

9. The system (1') as claimed in claim 8, wherein the carrier (4) is configured in the form of a foil and / or wherein the carrier (4) is configured in a flexible manner and / or wherein the carrier (4) is made of metal.

10. The system (1') as claimed in claim 8, wherein the carrier (4) is designed in the form of a rigid carrier and / or wherein the carrier (4) consists of plastic.

11. The system (1') according to claim 10, wherein the carrier (4) and the expanded material (3') are produced by a two-component injection molding process.

12. The system (1') according to any one of claims 1 to 7, wherein the spacer element (2) does not contain any carrier (4).

13. System (1') according to claim 12, wherein the spacer element (2) is fixed to the structure of the channel (5) by means of an adhesive film.

14. System (1') according to claim 12, wherein the isolation element (2) is fixed to the structure of the channel (5) by push pins.

15. The system (1') according to any one of the preceding claims, wherein the system (1) is in a motor vehicle without an internal combustion engine.

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