Temperature control device for an energy storage system

Abstract

Tempering device (1) of an energy storage device (2), in particular in a motor vehicle, - with a first circuit (4) in which a first heat exchanger (5) and the energy storage device (2) to be tempered are arranged and are connected in a heat-transfer manner via a first heat transfer medium (6), - with a second circuit (7) in which a second heat exchanger (8) and the first heat exchanger (5) are arranged and are connected in a heat-transfer manner via a second heat transfer medium (9), characterized in that - that in at least one line (10) of the first circuit (4) and / or in at least one line (11) of the second circuit (7) a predetermined kink point (13) is arranged, which interrupts a flow of the first heat transfer medium (6) and / or the second heat transfer medium (9) in the respective associated circuit (4, 7) when a predefined force (14) is applied, but prevents the heat transfer medium (6, 9) from escaping into the environment.

Description

[0001] The present invention relates to a temperature control device for an energy storage device, in particular in a motor vehicle. The invention also relates to a motor vehicle, in particular an electric vehicle, with an energy storage device and such a temperature control device for controlling the temperature, in particular for cooling, of this energy storage device.

[0002] In order to increase the performance of electric vehicles in particular, it is necessary to operate their energy storage devices within an optimal temperature window, for which purpose temperature control devices are usually used to cool or, if necessary, heat the energy storage device.

[0003] From DE 10 2019 109 750 A1, a generic temperature control device of an energy storage device is known, comprising a first circuit in which a first heat exchanger and the energy storage device to be temperature controlled are arranged and are connected in a heat-transferring manner via a first heat transfer medium, and a second circuit in which a second heat exchanger and the first heat exchanger are arranged and are connected in a heat-transferring manner via a second heat transfer medium.

[0004] DE 10 2015 003 119 A1 discloses a vehicle with at least one electric motor and an air conditioning system, with which at least one high-voltage component, in particular at least one energy storage device and / or at least one power electronics as a high-voltage component, can be cooled. The air conditioning system has a rechargeable cold storage device as an energy buffer, which can be used and / or discharged for cooling the at least one high-voltage component at a defined time and / or in a defined operating situation, in particular with the engine switched off during stationary operation for post-cooling.

[0005] Further temperature control devices are known from DE 10 2019 007 737 A1, DE 10 2017 004 723 A1, DE 10 2019 126 848 A1, DE 10 2014 210 158 A1, DE 10 2014 204 263 A1 and DE 10 2019 204 270 A1.

[0006] In order to achieve particularly effective temperature control of the energy storage device, individual energy storage cells of the energy storage device can be in direct contact with a heat transfer medium, for example, a dielectric fluid. A dielectric heat transfer medium is required to prevent short circuits. The dielectric fluid used can be, for example, oil, which is temperature-controlled in a heat exchanger integrated into a further circuit via a conventional coolant cooler. Such a coolant cooler contains an aqueous heat transfer medium, in particular a glycol-water mixture.In the event of an accident involving a motor vehicle equipped with a directly cooled energy storage device, such as an electric vehicle, it is essential to prevent the aqueous heat transfer medium in the radiator circuit from mixing with the dielectric heat transfer medium used for direct cooling or temperature control of the electrical energy storage device. Otherwise, if the aqueous heat transfer medium penetrates a directly cooled or temperature-controlled energy storage device, this could lead to the development of oxyhydrogen gas (HHO) through electrolysis and, as a result, a vehicle fire. Unfortunately, this cannot be completely ruled out in conventional motor vehicles, especially in conventional electric vehicles.

[0007] The present invention therefore addresses the problem of providing an improved or at least an alternative embodiment for a temperature control device which, in particular, overcomes the disadvantages known from the prior art.

[0008] This problem is solved according to the invention by the subject matter of independent claim 1.

[0009] Advantageous embodiments are the subject of the dependent claims.

[0010] The present invention is based on the general idea of ​​interrupting a heat transfer medium circuit in the event of a crash by simply providing at least one predetermined kink point, thereby particularly effectively preventing undesired penetration of water-containing heat transfer medium into a directly cooled energy storage device, while preventing the heat transfer medium from escaping into the environment. The temperature control device for an energy storage device according to the invention has a first circuit in which a first heat exchanger and the energy storage device to be temperature-controlled are arranged and are connected to one another in a heat-transferring manner via a first heat transfer medium. The temperature control device also has a second circuit in which a second heat exchanger, for example a coolant cooler, and the first heat exchanger are arranged and are connected to one another in a heat-transferring manner via a second heat transfer medium.In at least one line of the first circuit and / or in at least one line of the second circuit, the predetermined kink point according to the invention is now provided, which interrupts a flow of the first heat transfer medium and / or the second heat transfer medium in the respective associated circuit when a predefined force is applied, but in any case prevents access of the second heat transfer medium to the energy storage device, but prevents the heat transfer medium from escaping into the environment.

[0011] This makes it relatively easy to prevent crash-related direct contact between the water-containing heat exchanger medium and the energy storage cells of the energy storage system, and the associated potential development of oxyhydrogen gas and a vehicle fire. Such predetermined kink points can be installed relatively easily at suitable locations with extremely minimal installation space requirements, so that they simply trigger in the event of a vehicle crash, for example, a head-on collision, thereby blocking the respective circuit in which they are located by kink.In the event of a crash, the predetermined kink point can be used, particularly in the area of ​​the first heat exchanger, to prevent the second heat exchanger medium from coming into contact with the first heat exchanger medium, thereby preventing the second heat exchanger medium from being transported via the first circuit to the energy storage device, where it may cause the development of oxyhydrogen gas or a fire.

[0012] The first heat exchanger is expediently an oil cooler. The first heat exchange medium is typically a dielectric fluid, particularly oil, which is essential for direct cooling of the energy storage device, in which its energy storage cells are directly immersed in the first heat exchange medium.

[0013] In an advantageous development of the temperature control device according to the invention, the second heat exchanger is a coolant cooler. Such a coolant cooler is generally present in motor vehicles with an internal combustion engine, but also in hybrid vehicles or purely electric vehicles, wherein an electrically conductive fluid, usually a glycol-water mixture, is cooled in the second heat exchanger. However, such a coolant cooler can not only indirectly control the temperature of the first heat exchanger medium in the first circuit and thus the energy storage device, in particular cool it, via the first heat exchanger, but also further heat exchangers can be arranged in the second circuit, for example a refrigerant cooler of an air conditioning system.

[0014] Coolant coolers are now available in a wide variety of designs and have been tried and tested for many years. They enable a comparatively high cooling performance with a comparatively small installation space requirement.

[0015] In this case, a heating device can of course be provided in at least the first circuit, via which the first heat exchange medium flowing in the first circuit and, above it, the energy storage device can be heated in order to be able to keep the latter in a temperature window that is optimal for operation, particularly at low outside temperatures.

[0016] In a further advantageous embodiment of the temperature control device according to the invention, the predetermined bending point has a constriction, a notch, or a predefined bend. Compared to a predetermined breaking point, a predetermined bending point offers the major advantage that, in the event of a crash, it merely bends, thus preventing the heat transfer medium flowing in this circuit. However, unlike a predetermined breaking point, it prevents the heat transfer medium from escaping into the environment. Even this non-exhaustive list of possible embodiments of the predetermined bending point gives an idea of ​​the diverse embodiments that are conceivable here, although in principle, such a predetermined bending point is preferable to a predetermined breaking point for the reasons stated above.

[0017] The energy storage device expediently has energy storage cells that are in direct contact with the first heat transfer medium. In order to achieve particularly effective cooling, i.e. in particular direct cooling, direct application of cooling fluid, in particular a dielectric fluid, to the energy storage cells is usually preferred, since in this case the heat transfer and thus also the cooling performance is significantly improved compared to indirect cooling, for example via a heat transfer plate. This makes it much easier to keep the energy storage device within a temperature window that is optimal for its operation. However, direct cooling, in which the energy storage cells are in direct contact with the first heat transfer medium, requires the use of a dielectric fluid, since otherwise short circuits can occur.

[0018] The present invention is further based on the general idea of ​​equipping a motor vehicle, in particular an electric vehicle, with an energy storage device with such a temperature control device according to the previous paragraphs for temperature control of this energy storage device. The motor vehicle according to the invention offers the great advantage that in the event of an accident, there is no mixing of an electrically conductive fluid, for example a glycol-water mixture, and the dielectric fluid, for example oil, and thus no direct contact of energy storage cells with the glycol-water mixture, which can in particular prevent the development of oxyhydrogen gas and, under certain circumstances, even a vehicle fire. The predetermined kink point makes it possible to avoid direct contact between the second heat exchanger medium, for example a water-containing coolant, and the energy storage cells in a comparatively simple manner.

[0019] Further important features and advantages of the invention emerge from the subclaims, from the drawings and from the associated description of the figures with reference to the drawings.

[0020] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0021] Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical components.

[0022] They show, schematically, Fig. 1 a temperature control device according to the invention for an energy storage device in the normal state with a predetermined bending point and a predetermined breaking point, Fig. 2 a representation as in Fig. 1, but after an impact with a bent predetermined bending point and a broken predetermined breaking point.

[0023] According to the Fig. 1 and Fig. 2, a temperature control device 1 according to the invention for an energy storage device 2, in particular in an electric vehicle 3, has a first circuit 4, in which a first heat exchanger 5 and the energy storage device 2 to be temperature-controlled are arranged and are connected to one another for heat transfer via a first heat transfer medium 6. Also provided is a second circuit 7, in which a second heat exchanger 8, in particular a coolant cooler, and the first heat exchanger 5 are arranged and are connected to one another for heat transfer via a second heat transfer medium 9. In the first heat exchanger 5, heat is transferred between the first heat transfer medium 6 flowing in the first circuit 4, for example a dielectric fluid, in particular oil, and a second heat transfer medium 9 flowing in the second circuit 7, for example a glycol-water mixture.

[0024] According to the invention, a predetermined bending point 13 is arranged in at least one line 10 of the first circuit 4 and / or in at least one line 11 of the second circuit 7, which bends when a predefined force 14 is applied (cf. Fig. 2) interrupts a flow of the first heat transfer medium 6 and / or the second heat transfer medium 9 in the respective associated circuit 4, 7.

[0025] According to the Fig. 1, a predetermined breaking point 12 is arranged in the line 10 of the first circuit 4, while the predetermined bending point 13 is arranged in the line 11 of the second circuit 7. Of course, it is conceivable that such a predetermined bending point 13 can also be arranged in the line 10 as an alternative to the predetermined breaking point 12.

[0026] The energy storage device 2 has energy storage cells 15 which are in direct contact with the first heat transfer medium 6, for example the oil, whereby a particularly effective cooling of the energy storage device 2 can be achieved compared to indirect cooling, for example via a heat exchanger plate.

[0027] In order to achieve improved cooling of the energy storage system 2, the first circuit 4 is coupled to the second circuit 7 via the first heat exchanger 5 in a heat-transfer manner, so that the coolant cooler, or generally a second heat exchanger 8, cools the first heat transfer medium 6 via the first heat exchanger 5, which can be designed, for example, as an oil cooler. This is particularly advantageous because other components of the electric vehicle 3, for example, a refrigerant cooler of an air conditioning system or a transmission oil cooler, can also be temperature-controlled, in particular cooled, via the coolant cooler.

[0028] In the event of a vehicle crash, for example in a rear-end collision, a force 14 is exerted (cf. Fig.2) onto a front section of the electric vehicle 3, whereupon, for example, the second heat exchanger 8 arranged at the front, i.e., the coolant cooler, can be displaced. In purely theoretical terms, this can lead to damage to the first heat exchanger 5, so that in the worst case scenario, mixing of the second heat exchanger medium 9, which usually contains water, and the dielectric first heat exchanger medium 6 in the first heat exchanger 5 is to be feared, so that in the further course, the water-containing second heat exchanger medium 9 can enter the energy storage device 2 and the energy storage cells 15, which in turn can potentially lead to the development of oxyhydrogen gas and a vehicle fire or a short circuit.

[0029] In order to avoid this or at least reduce the risk thereof, the predetermined bending point 13 is provided, which bends when a predefined force 14 is applied, for example in the event of an accident, and thereby prevents a mixing of the two heat transfer media 9, 6 and direct contact of the second heat transfer medium 9 with the energy storage cells 15.

[0030] The predetermined breaking point 12 can be designed, for example, as a thinned material section or as a brittle development that breaks upon application of a predefined force, whereby the dielectric fluid, i.e., the first heat exchanger medium 6, can no longer flow or can only flow for a short time in the first circuit 4. The predetermined breaking point 12 can be arranged either in a supply line to the first heat exchanger 5 or in a discharge line therefrom.

[0031] The predetermined kink point 13 can be designed, for example, as a constriction, as a notch, or as a predefined kink and can be arranged in a supply line or discharge line to the first heat exchanger 5. In purely theoretical terms, an arrangement directly on the first heat exchanger 5 or on the second heat exchanger 8 is of course also conceivable. The advantage of the predetermined kink point 13 lies in particular in the fact that it kinked when a predefined force 14 is applied, preventing further flow of the second heat exchanger medium 9 in the second circuit 7 or, in the case of an arrangement in the first circuit 4, preventing flow of the first heat exchanger medium 6 flowing there, but preventing leakage of the respective heat exchanger medium 9, 6, as is to be feared with a predetermined breaking point.

[0032] At least one line 10 in the first circuit 4 and / or the at least one line 11 in the second circuit 7 can be made of plastic or metal, which makes it relatively easy to form the predetermined bending point 13. Such a predetermined bending point 13 can also be inserted into the line 10, 11 as a prefabricated component.

[0033] With the temperature control device 1 according to the invention and the motor vehicle according to the invention, in particular the electric vehicle 3, damage such as a short circuit, the development of oxyhydrogen gas or even a vehicle fire in the event of a vehicle crash can be prevented, or at least the risk thereof can be reduced.

Claims

[1] Temperature control device (1) of an energy storage device (2), in particular in a motor vehicle, - with a first circuit (4) in which a first heat exchanger (5) and the energy storage device (2) to be tempered are arranged and are connected in a heat-transfer manner via a first heat transfer medium (6), - with a second circuit (7) in which a second heat exchanger (8) and the first heat exchanger (5) are arranged and are connected in a heat-transfer manner via a second heat transfer medium (9), characterized by , - that in at least one line (10) of the first circuit (4) and / or in at least one line (11) of the second circuit (7) a predetermined kink point (13) is arranged, which interrupts a flow of the first heat transfer medium (6) and / or the second heat transfer medium (9) in the respective associated circuit (4, 7) when a predefined force (14) is applied, but prevents the heat transfer medium (6, 9) from escaping into the environment. [2] Tempering device (1) according to claim 1, characterized by that the first heat exchanger (5) is an oil cooler. [3] Tempering device (1) according to claim 1 or 2, characterized by that the first heat transfer medium (6) is a dielectric fluid, in particular oil. [4] Tempering device (1) according to one of the preceding claims, characterized by that the second heat exchanger (8) is a coolant cooler. [5] Tempering device (1) according to one of the preceding claims, characterized by that the second heat transfer medium (9) is an electrically conductive fluid, in particular a glycol-water mixture. [6] Tempering device (1) according to one of the preceding claims, characterized by that the predetermined bending point (13) has a constriction, a notch or a predefined bend. [7] Tempering device (1) according to one of the preceding claims, characterized by that the at least one line (10) in the first circuit (4) and / or the at least one line (11) in the second circuit (7) are / is made of plastic or metal. [8] Tempering device (1) according to one of the preceding claims, characterized by that the energy storage device (2) has energy storage cells (15) which are in direct contact with the first heat transfer medium (6). [9] Motor vehicle, in particular an electric vehicle (3), with an energy storage device (2) and a temperature control device (1) according to one of the preceding claims for temperature control of this energy storage device (2).

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