ELECTRICAL ENERGY STORAGE FOR A MOTOR VEHICLE

Abstract

Electrical energy storage device (1) for a motor vehicle, comprising a storage housing (2) in which energy storage cells (4) of the electrical energy storage device (1) and a temperature control device (5) for temperature control of the electrical energy storage device (1) are accommodated in an interior space (3) of the storage housing (2), wherein the temperature control device (5) has at least one temperature control channel (6) through which a temperature control medium (7), in particular a liquid, can be guided or is guided, wherein the temperature control device (5) has a diffusion stop device (13) which is designed to reduce diffusion of the temperature control medium (7) from the at least one temperature control channel (6) into the interior space (3) of the storage housing (2).

Description

The invention relates to an electrical energy store for a motor vehicle, comprising a storage housing in which energy storage cells of the electrical energy store and a temperature control device for temperature control of the electrical energy store are accommodated in an interior of the storage housing, wherein the temperature control device has at least one temperature control channel through which a temperature control medium, in particular a liquid, can be guided or is guided.When using electrical energy stores of the type mentioned at the beginning, it is known from the prior art that introducing moisture into the interior of the storage housing can have a negative effect on the components arranged in the interior of the storage housing, for example the electrical energy storage cells, electrical contacts, mechanical properties of structural elements and the like. Moisture can enter the storage housing, for example, by air entering the storage housing due to a pressure compensation or by diffusion through a wall of the storage housing from the environment into the interior space. In addition to the possibility of absorbing moisture from the environment, moisture can also penetrate into the interior by diffusion from assemblies within the interior. For example, electrical energy stores can have temperature control devices which guide a temperature control medium into temperature control channels. For example, with such temperature control devices, heat can be dissipated from the interior of the storage housing, for example from the energy storage cells. The tempering medium is usually a liquid, in particular a water-glycol mixture. The liquid can also penetrate into the interior by diffusion through the wall of the temperature control channel.The object of the invention is to specify an electrical energy store which is improved in comparison with it, in which, in particular, absorption of moisture from a temperature control device into the interior of the storage housing is reduced.The object is achieved by an electrical energy store according to claim 1. The claims dependent thereon relate to possible embodiments.As described, the invention relates to an electrical energy store for a motor vehicle, which has a storage housing in which the energy storage cells of the electrical energy store are arranged. Furthermore, a temperature control device is arranged in the interior space, which is designed for the temperature control of the electrical energy store, in particular for the temperature control of the energy store cells arranged in the electrical energy store. For the purpose of tempering the energy storage cells or the electrical energy storage device, the tempering device has at least one tempering channel through which a tempering medium, in particular a liquid, is guided. In other words, the temperature control medium is guided through the temperature control channel in such a way that a heat exchange is possible between the temperature control medium and the interior space, in particular between the liquid and the energy storage cells. The term "temperature control channel" can, in the context of this application, relate to any channel section in the interior of the storage housing in which liquid is guided.The invention is based on the finding that the temperature control device has a diffusion stop device which is designed to reduce a diffusion of the temperature control medium from the at least one temperature control channel into the interior of the storage housing. The diffusion stop device is arranged, for example, on the temperature control channel or is applied to the temperature control channel such that a diffusion of the temperature control medium from the interior of the temperature control channel, in particular through the wall of the temperature control channel, into the interior of the storage housing can be reduced. Advantageously, the diffusion stop device can surround the temperature control channel at least in sections, so that a diffusion of the temperature control medium from the temperature control channel into the interior is at least reduced or completely prevented. Depending on which diffusion stop device and how it is applied to or arranged on the temperature control channel, the diffusion of the temperature control medium can be proportionally reduced or completely prevented due to a reduction in the free surface of the temperature control channel or due to a layer thickness of the diffusion stop device. For example, this can be achieved by the diffusion stop device being formed from a different material than the temperature control channel or its wall. If the temperature control channel is formed, for example, from a plastic which does not prevent a diffusion of the temperature control medium, the diffusion stop device can at least reduce the described diffusion by a suitable choice of material, for example from a metal.According to one configuration of the electrical energy store, the at least one temperature control channel can be configured as an inlet channel or outlet channel, in particular between a housing connection of the storage housing and a temperature control body inlet or temperature control body outlet. As described, the "temperature control channel" can fundamentally relate to any channel section of the temperature control device within the storage housing in which a temperature control medium, in particular a liquid, is guided. According to the described embodiment, the temperature control channel can be designed as an inlet channel or outlet channel, i.e. the temperature control channel is connected between the housing connection of the storage housing, at which the temperature control channel is guided outwards or to a unit arranged outside the storage housing, for example a reservoir or a pump, and extends to the temperature control body inlet or outlet in the interior of the storage housing.The temperature control body inlet or outlet can in particular establish the connection between the temperature control channel and a temperature control body. A temperature control body can be understood to mean, for example, a temperature control structure, in particular a heat-conducting structure or a heat exchanger. If the temperature control body and / or the temperature control body inlet or outlet itself is formed from a material which prevents a diffusion of the temperature control medium into the interior of the storage housing, it is sufficient to surround the remaining temperature control channel sections, which are designed, for example, as a plastic hose, by the diffusion stop device. The at least one temperature control channel can thus represent, for example, the inlet and / or the outlet of the temperature control body.The electrical energy store can further be developed to the effect that the diffusion stop device has at least one at least partially enveloping of the temperature control channel. As described at the beginning, the at least one temperature control channel is surrounded at least in sections by the diffusion stop device, so that temperature control medium cannot overcome the diffusion stop device. The casing can enclose the temperature control channel such that moisture cannot enter the interior space from the temperature control channel, i.e. cannot leave the casing.According to a further embodiment of the electrical energy store, the diffusion stop device can enclose the at least one temperature control channel over part of the surface or over the entire surface. In this case, the diffusion of the temperature control medium through the wall of the temperature control channel is reduced proportionally, depending on the surface proportion of the surface of the temperature control channel surrounded by the diffusion stop device. In order to reduce the diffusion as completely as possible, a full-surface enclosure of the temperature control channel by the diffusion stop device is appropriate.The diffusion stop device can furthermore have a diffusion stop layer, in particular a metal layer or a lacquer layer, which surrounds the at least one temperature control channel at least in sections. The diffusion stop layer can be applied, for example, over the circumference or the length of the temperature control channel. In other words, the diffusion stop layer can cover the at least one temperature control channel and thus have a diffusion-reducing effect. Depending on the thickness of the diffusion stop layer, the proportion of diffusion from the temperature control channel into the interior can be reduced and, with a sufficiently thick diffusion stop layer, completely prevented. As described, a metal layer, for example a layer of aluminum, can be applied to the temperature control channel as a diffusion stop layer. Furthermore, lacquers can be used which can contain metal particles in particular.According to a further embodiment of the electrical energy store, the diffusion stop device can have a diffusion stop film, in particular a metal film, which is arranged around the at least one temperature control channel, in particular in a self-adhesive manner. The described diffusion stop film can in principle be applied to the temperature control channel as desired or arranged around the latter. For example, the diffusion stop film can also be wound around the temperature control channel. It is appropriate to make the diffusion-stop film self-adhesive, so that the assembly of the diffusion-stop film can be simplified. For example, aluminum foil can be arranged around the temperature control channel, which reduces or prevents a diffusion from the temperature control channel into the interior. It is likewise possible to form the diffusion stop film by deep drawing and to arrange the temperature control channel. The diffusion stop device thus generally represents a vapor-tight housing for the at least one temperature control channel, so that an escape of liquid from the temperature control channel into the interior is reduced, in particular prevented.The electrical energy store can furthermore be further developed to the effect that the diffusion stop device has an at least partially surrounding of the at least one temperature control channel, in particular a clip or a shell. The diffusion stop device can thus be designed as a clip or shell and be arranged around the temperature control channel. For example, the diffusion stop device can have a flat clip, which is clipped onto the temperature control channel.Furthermore, the diffusion stop device can be connected to an electrical potential of the electrical energy store, in particular a ground connection. The configuration enables the diffusion stop device, which as described can represent a metallic layer or a metallic element, to be linked to a defined electrical potential of the electrical energy store. For example, the diffusion stop device can be connected to a ground terminal of the electrical energy store. For this purpose, the diffusion stop device can be electrically conductively connected to the housing of the electrical energy store. This offers the particular advantage that requirements for contact protection, potential compensation and the like can be fulfilled.The electrical energy store can be further developed to the effect that the diffusion stop device has at least one diffusion stop element arranged on a wall element of the storage housing. In addition to reducing or preventing entry of liquid from the temperature control channel into the interior space, by providing the diffusion stop element, entry of liquid by diffusion from the environment into the interior space can also be prevented. The diffusion stop element can be arranged on the wall element of the storage housing in such a way that diffusion of moisture from the environment into the interior space is prevented or at least reduced. For example, the wall element can likewise be covered with a diffusion stop layer, for example a diffusion stop film, or such a layer can be arranged on it that liquid cannot diffuse through the wall element or such a diffusion is at least reduced.In addition to the electrical energy store, the invention relates to a motor vehicle which has such an electrical energy store described above.All advantages, details, embodiments and / or features described with reference to the electrical energy store can be completely transferred to the motor vehicle.The invention is explained on the basis of exemplary embodiments with reference to the figures. The figures are schematic representations and show: FIG. 1 shows a schematic illustration of a detail of a motor vehicle, comprising an electrical energy store according to a first exemplary embodiment; FIG. 2 shows a schematic illustration of a detail of a temperature control duct of the electrical energy store of FIG. 1 according to a second exemplary embodiment; and FIG. 3 shows a schematic illustration of a detail of a temperature control duct of the electrical energy store of FIG. 1 according to a third exemplary embodiment.FIG. 1 shows a schematic detail of a motor vehicle, which has an electrical energy store 1 which comprises a storage housing 2, in the interior 3 of which energy store cells 4 are arranged. Furthermore, a temperature control device 5 is arranged in the interior 3 of the storage housing 2, which is designed to control the temperature of the interior 3, in particular of the energy storage cells 4. The temperature control device 5 has a plurality of temperature control channels 6, through which a temperature control medium 7 is guided. The temperature control channels 6 extend, purely by way of example, from an inlet channel 8 to an outlet channel 9. For example, the inlet channel 8 extends from a first housing connection 10 of the storage housing 2 to a temperature control body inlet 11 of a temperature control body, for example a heat exchanger or a channel structure of the temperature control device 5 running between the energy storage cells 4.The electrical energy store 1 has a diffusion stop device 13, which is formed on the inlet duct 8 and an outlet duct 9 in the exemplary embodiment shown. For example, the temperature control body can be formed from a different material than the inlet channel 8 and the outlet channel 9. In particular, the inlet channel 8 and the outlet channel 9 are produced from a plastic, i.e. their outer wall, which faces the interior 3 and which separates the interior 3 from the temperature control medium 7, is produced from a plastic. In order to prevent a diffusion of the temperature control medium 7 from the temperature control channel 6 into the interior 3 or to reduce the amount of temperature control medium 7 that can diffuse into the interior 3 through the wall of the temperature control channel 6, the diffusion stop device 13 is provided on the inlet channel 8 and the outlet channel 9. The diffusion stop device 13 surrounds the inlet channel 8 and the outlet channel 9 at least in sections, in particular completely. In principle, it is also possible to surround any other region of the temperature control channel 6, i.e. also in the region of the temperature control body, in particular of the temperature control body inlet 11 and of the temperature control body outlet 12, by a diffusion stop device 13. Alternatively, only the inlet channel 8 or the outlet channel 9 can also be surrounded by a diffusion stop device 13.FIG. 2 shows a schematic longitudinal section through a temperature control channel 6, for example the inlet channel 8 or the outlet channel 9. In the section of the longitudinal section through the temperature control channel 6 shown, i.e. along its longitudinal axis or longitudinal extent, it can be seen that a wall 14 of the temperature control channel 6 separates the interior 3 from the temperature control medium 7 or the temperature control medium 7 is guided within the wall 14. In order to prevent or at least reduce a diffusion of the temperature control medium 7, for example a water-glycol mixture, through the wall 14, a diffusion stop device 13 is provided which surrounds the temperature control channel 6. For example, the diffusion stopper 13 includes a diffusion stopper layer 15. The diffusion stopper layer 15 may be formed by, for example, a metal coating or a paint, particularly including metallic particles. The diffusion stop layer 15 can likewise be designed as a film, in particular a self-adhesive film. The diffusion stop layer 15 can be designed, for example, as a self-adhesive aluminum foil or any other metal foil and can surround the temperature control channel 16 at least in sections, in particular over the entire surface.FIG. 3 shows a further exemplary embodiment of an electrical energy store 1, comprising a diffusion stop device 13 for a temperature control channel 6. as an alternative or in addition to the embodiment in FIG. 2, the diffusion stop layer 13 can have a casing 16 which surrounds the temperature control channel 6. For example, the enclosure 16 may be formed from a metal, for example a deep-drawn sheet or a foil, in particular from aluminum. The enclosure 16 can be clipped onto the temperature control channel 6 and at least partially enclose the latter.FIGS. 2, 3 also show a connection of the diffusion stop device 13 to a defined electrical potential 17. For example, the potential 17 can establish the connection to a ground terminal of the electrical energy store 1, in particular form a connection to the storage housing 2. This makes it possible to ensure that an, in particular metallic, portion of the diffusion stop device 13 is connected to the defined electrical potential, for example in order to implement requirements with respect to potential compensation.The advantages, details and features described in the individual exemplary embodiments can be combined with one another as desired, interchanged and transferred to one another.List of reference characters1 Electrical energy store 2 Storage housing 3 Interior space 4 Energy store cell 5 Temperature control device 6 Temperature control channel 7 Temperature control medium 8 Inlet channel 9 Outlet channel 10, 10' Housing connection 11 Temperature control body inlet 12 Temperature control body outlet 13 Diffusion stop device 14 Wall 15 Diffusion stop layer 16 Enclosure 17 Potential

Claims

Electrical energy store (1) for a motor vehicle, comprising a storage housing (2) in which energy storage cells (4) of the electrical energy store (1) and a temperature control device (5) for temperature control of the electrical energy store (1) are accommodated in an interior space (3) of the storage housing (2), wherein the temperature control device (5) has at least one temperature control channel (6) through which a temperature control medium (7), in particular a liquid, can be guided or is guided, characterized in that the temperature control device (5) has a diffusion stop device (13) which is designed to reduce diffusion of the temperature control medium (7) from the at least one temperature control channel (6) into the interior space (3) of the storage housing (2).Electrical energy store (1) according to Claim 1, characterized in that the at least one temperature-control duct (6) is designed as an inlet duct (8) and / or an outlet duct (9), in particular between a housing connection of the storage housing (2) and a temperature-control body inlet (11) or a temperature-control body outlet.Electrical energy store (1) according to Claim 1 or 2, characterized in that the diffusion stop device (13) has at least one at least partially enveloping of the temperature control duct (6).Electrical energy store (1) according to one of the preceding claims, characterized in that the diffusion stop device (13) encloses the at least one temperature control channel (6) over part of the surface or over the entire surface.Electrical energy store (1) according to one of the preceding claims, characterized in that the diffusion stop device (13) has a diffusion stop layer (15), in particular a metal layer or a lacquer layer, which surrounds the at least one temperature control channel (6) at least in sections.Electrical energy store (1) according to one of the preceding claims, characterized in that the diffusion stop device (13) has a diffusion stop film, in particular a metal film, which is arranged around the at least one temperature control channel, in particular in a self-adhesive manner.Electrical energy store (1) according to one of the preceding claims, characterized in that the diffusion stop device (13) has an at least partially surrounding (16) of the at least one temperature control channel, in particular a clip or a shell.Electrical energy store (1) according to one of the preceding claims, characterized in that the diffusion stop device (13) is connected to an electrical potential (17) of the electrical energy store (1), in particular to a ground connection.Electrical energy store (1) according to one of the preceding claims, characterized in that the diffusion stop device (13) has at least one diffusion stop element arranged on a wall element of the storage housing (2).Motor vehicle comprising an electrical energy store (1) according to one of the preceding claims.

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