Heat storage arrangement for a vehicle battery and method for its operation

Abstract

Heat storage arrangement (100) configured for the use of engine waste heat for preheating a battery (310) designed as a traction battery of an electric or hybrid motor vehicle, with a first cooling circuit (200) which has at least - a drive motor (210) designed as an internal combustion engine, generating waste heat, wherein the waste heat is dissipated by means of a first coolant, - a heat storage unit (230) was set up to store the waste heat contained in the first coolant, - a heat exchanger (240) provided for the use of the waste heat contained in the first coolant, wherein the heat exchanger (240) is integrated into the first cooling circuit (200) by means of a first three-way valve (231), - a first cooler (220) for dissipating the waste heat contained in the first coolant to the environment, and with a second cooling circuit (300) which has at least - a battery (310) designed as a traction battery of an electric or hybrid motor vehicle, configured to store electrical energy for supplying an electric motor, wherein the battery (310) is cooled by means of a second coolant, - a second cooler (320) configured for dissipating heat contained in the second coolant to the environment, characterized in that the first cooling circuit (200) is fluidically coupled to the second cooling circuit (300) by means of a first and a second connecting line (410, 420), wherein the first cooling circuit (200) has a first connecting line (410) arranged downstream of the heat exchanger (240), which opens into a second three-way valve (330) which is integrated into the second cooling circuit (300) immediately upstream of the battery (310), wherein a second connecting line (420) for extracting the first coolant and / or a mixture of the first and second coolant is fluidically connected to the second cooling circuit (300) immediately downstream of the battery (310), wherein the second connecting line (420) opens into the first cooling circuit (200) immediately upstream of the first pump (232),wherein the waste heat stored in the heat storage unit (230) can be used by means of the first coolant to preheat the battery (310) designed as a traction battery of an electric or hybrid motor vehicle.

Description

[0001] The present invention relates to a heat storage arrangement configured to utilize engine waste heat to preheat a battery, i.e., a traction battery of an electric or hybrid motor vehicle, having the features of the preamble of claim 1. Furthermore, the invention relates to a method for operating a heat storage arrangement having the features of the preamble of claim 4.

[0002] In addition to combustion engines such as diesel, gasoline, or gas engines, alternative drive solutions are also used in modern motor vehicles. Especially with regard to reducing exhaust gases and pollutant emissions, the use of electric motors in purely electric or hybrid vehicles with any degree of hybridization is a suitable option. Vehicles with battery-electric drive require, in addition to a fuel tank if necessary, a battery, particularly a traction battery, to store the electrical drive energy. The use of lithium-ion high-performance batteries is well known; their optimal operating temperature is typically between approximately 20°C and 30°C. This temperature should be kept as constant as possible to ensure a long battery service life.

[0003] However, motor vehicles present a challenging environment for electrical components, both mechanically and thermally. The thermal integration of the electric motor, battery, and power electronics results in complex and coupled cooling systems. In hybrid vehicles, the cooling circuit of the combustion engine has so far differed little from that of conventional combustion vehicles. Due to different operating temperatures, the cooling circuit of a combustion engine cannot be used for the battery. Hybrid vehicles therefore require a separate cooling circuit for the battery in addition to the conventional cooling circuit for the drive motor. Depending on the drive train and battery type, different cooling circuits are appropriate for the electrical system.

[0004] On the other hand, operation at outside temperatures that are too low can lead to a shortened battery life. For vehicles with a battery-electric drive, cold starting in very cold conditions (for example when the outside temperature is below 0°C) represents a technological challenge, as the available battery power drops steeply as the temperature drops. A cold start occurs, among other things, when the vehicle is started up again after a long period of inactivity in a cold environment or when the temperature of the engine, battery or other drive-related components is below their operating temperature. Below a critical temperature limit, the vehicle can therefore no longer be operated electrically. However, especially with plug-in hybrid vehicles, the user expects to be able to start and drive the vehicle electrically, even after a long period of inactivity.

[0005] The problem of cold starts has long been recognized in the field of motor vehicles with internal combustion engines. Especially in diesel engines, cold starts lead to increased fuel consumption and increased pollutant emissions. State-of-the-art technology offers a variety of options for preheating the internal combustion engine after a prolonged period of inactivity to avoid cold starts or at least to keep the warm-up phase after a cold start as short as possible.

[0006] For example, DE 10 2011 017 764 A1 proposes a heat storage system for a motor vehicle with an internal combustion engine to store the waste heat generated by the internal combustion engine during driving. After a prolonged period of inactivity of the motor vehicle, the stored thermal energy can be used to heat the internal combustion engine to its operating temperature. The system comprises a fluidic charging circuit for charging the heat storage unit with the engine's waste heat and a discharging circuit through which the heat stored in the heat storage unit is supplied to the internal combustion engine.

[0007] DE 44 02 215 A1 also discloses a method for improving the cold-start performance of internal combustion engines. In this method, the waste heat from the internal combustion engine is stored in at least one heat accumulator, which absorbs the thermal energy from the engine oil or cooling water. The cooling water or the engine oil itself is used as the storage medium. Before a cold start, the engine oil is pumped from the heat accumulator back into the oil pan to warm the internal combustion engine to operating temperature.

[0008] An alternative embodiment of a heat accumulator is known, for example, from EP 2 143 573 B1. This discloses a heating device for heating components of a motor vehicle, such as a radiator. The heating device has a heat accumulator suitable for temporarily storing a released amount of heat over a period of time. The heat accumulator is designed as a latent heat accumulator. Latent heat accumulators have a separate storage medium and generally utilize the enthalpy of reversible thermodynamic changes in the state of the storage medium (for example, the transition from the solid to the liquid phase). The stored heat can be used to heat the vehicle interior.

[0009] DE 10 2010 029 904 A1 proposes using a fuel tank for biogenic fuel of a hybrid vehicle with a two-stroke diesel engine simultaneously as a coolant storage device and latent heat storage device for preheating electrical components and / or the passenger compartment during a cold start of the diesel engine.

[0010] DE 10 2014 007 214 A1 also discloses a heat storage device for storing the waste heat of an internal combustion engine. The heat storage device is designed as a so-called Ruths storage device, in which the heat storage fluid exists in two phases, i.e., liquid and gaseous, thereby increasing the amount of heat that can be stored. Using an expansion machine, the heat stored in the fluid can be converted into mechanical energy and supplied to various vehicle components.

[0011] A recuperation system with multiple storage units for energy recovery and energy storage in a motor vehicle is known from DE 10 2013 209 837 A1. By providing different storage units, various energy domains (electrical, chemical, electrochemical, thermal, mechanical), for example, from braking, exhaust, and waste heat energy, can be temporarily stored, thereby increasing the efficiency of the recuperation system.

[0012] DE 10 2013 225 582 A1 discloses a lithium battery system with an electrochemical energy storage device. It is proposed to store thermal energy, which is generated, for example, during engine operation, in a heat storage device. In the case of a hybrid vehicle, the stored heat can be used to heat the engine and / or to regulate the temperature in the passenger compartment and / or to support an auxiliary heater.

[0013] A thermal management system for a vehicle with a first coolant circuit connected to the engine and a second coolant circuit suitable for heating or cooling a vehicle battery is proposed in DE 10 2015 103 032 A1. The first and second coolant circuits are thermally coupled via a refrigerant circuit and a heat exchanger.

[0014] DE 10 2015 208 100 A1, which is closest to the invention, also discloses a motor vehicle with a heat accumulator and a method for utilizing the heat contained in the heat accumulator to heat an internal combustion engine and / or for the vehicle interior heating. The waste heat from the internal combustion engine is fed to a heat accumulator during engine operation and stored there. The storage medium contained in the heat accumulator can be additionally heated using an electric heater. The stored heat can be used to bring the internal combustion engine back to its operating temperature as quickly as possible after a cold start, to heat other vehicle components such as the vehicle battery or a traction battery of an electric vehicle, and / or to heat the vehicle interior. Further explanations regarding the thermal coupling of the cooling circuit of the internal combustion engine with a cooling circuit of the vehicle battery are not provided in the document.

[0015] A battery temperature control device for heating and / or cooling a traction battery of an electric or hybrid vehicle is disclosed in DE 10 2015 106 382 A1. The device comprises a thermochemical heat storage device and a heat transfer element for heating and / or cooling the battery. The thermal coupling between the thermochemical heat storage device and the battery to be temperature-controlled is achieved via a heat transfer element.

[0016] DE 10 2013 209 045 A1 relates to a cooling system for a hybrid vehicle comprising a low-temperature cooling circuit with a low-temperature heat source, with a low-temperature cooler and with a low-temperature pump and comprising an independently operable high-temperature cooling circuit with a high-temperature heat source, with a high-temperature cooler and with a high-temperature pump, wherein the low-temperature cooling circuit and the high-temperature cooling circuit can be coupled for the purpose of heat exchange.

[0017] DE 10 2015 122 196 A1 relates to a cooling or heating circuit system for an electrically powered vehicle, with at least one electric motor integrated in a first cooling circuit, as well as with a battery integrated in a second cooling circuit, as well as with a connecting line which is arranged between the first and the second cooling circuit and which can be controlled by at least one switching valve, as well as with an electric charger for the battery which is integrated in the connecting line.

[0018] From US 2008 / 0 251 303 A1 a method for controlling a vehicle drive train is known which connects or keeps connected two cooling circuits, each of which is connected to a heat engine and to at least one electrical component, via at least one valve.

[0019] DE 10 2010 014 752 A1 discloses an arrangement comprising an electrical energy storage device connected to a cooling circuit and two exhaust gas release devices connected in series or parallel to another cooling circuit, wherein the exhaust gas release devices release the exhaust gas during operation of the arrangement. Coupling elements connect the electrical energy storage device to the latter cooling circuit, and pump devices for supplying the cooler and / or the electrical energy storage device with coolant are connected to each of the two cooling circuits.

[0020] In view of the state of the art shown, there are still opportunities for improvement in the use of the waste heat of a drive motor to preheat a battery, especially during a cold start.

[0021] The invention is therefore based on the object of improving a heat storage arrangement with an engine cooling circuit and a method for its operation, in particular to create an alternative and more cost-effective possibility for heat transfer between the engine cooling circuit and a separate battery cooling circuit.

[0022] According to the invention, the object is achieved by a heat storage arrangement having the features of claim 1.

[0023] A heat storage arrangement is shown which is designed to use engine waste heat to preheat a battery designed as a traction battery of an electric or hybrid motor vehicle, with a first cooling circuit which has at least - a drive motor designed as an internal combustion engine, generating waste heat, wherein the waste heat is dissipated by means of a first coolant, - a heat storage device is provided for storing the waste heat contained in the first coolant, - a heat exchanger configured to utilize the waste heat contained in the first coolant, in particular for a vehicle interior heater, wherein the heat exchanger is integrated into the first cooling circuit by means of a first three-way valve, - a first cooler for discharging the waste heat contained in the first coolant to the environment, and with a second cooling circuit which has at least - a battery designed as a traction battery of an electric or hybrid motor vehicle, designed to store electrical energy to power an electric motor, wherein the battery is cooled by means of a second coolant, - a second cooler arranged to release heat contained in the second coolant to the environment,

[0024] It is proposed that the first cooling circuit is fluidically coupled to the second cooling circuit by means of a first and a second connecting line, wherein the first cooling circuit has a first connecting line arranged downstream of the heat exchanger, which opens into a second three-way valve which is integrated into the second cooling circuit immediately upstream of the battery, wherein a second connecting line for removing the first coolant and / or a mixture of first and second coolant is fluidically connected to the second cooling circuit immediately downstream of the battery, wherein the second connecting line opens into the first cooling circuit immediately upstream of the first pump, wherein the waste heat stored in the heat accumulator can be used by means of the first coolant to preheat the battery designed as a traction battery of an electric or hybrid motor vehicle.

[0025] Further advantageous embodiments of the invention are disclosed in the subclaims.

[0026] It should be noted that the features and measures listed individually in the following description can be combined in any technically reasonable manner and demonstrate further embodiments of the invention. The description further characterizes and specifies the invention, particularly in conjunction with the figures.

[0027] As described above, a heat storage arrangement is proposed for utilizing engine waste heat to preheat a battery. In particular, the engine waste heat can be used to preheat a traction battery of an electric or hybrid motor vehicle with any degree of hybridization. The heat storage arrangement has a first cooling circuit, a high-temperature cooling circuit for cooling a drive motor, and a second cooling circuit, a low-temperature cooling circuit for cooling the battery. The drive motor is integrated into the first cooling circuit. This is an internal combustion engine (e.g., a diesel or gasoline engine, or a gas engine). If a purely electrically powered motor vehicle is used, it could also be a liquid-cooled electric motor. During engine operation, the drive motor generates waste heat, which is dissipated using a first coolant, preferably a water-based one.The first cooling circuit further comprises a heat accumulator, in particular a latent heat accumulator, and a first cooler. In order to retain stored heat for a sufficiently long period of time (e.g., overnight), the heat accumulator must be designed as an insulating container with sufficient thermal insulation. The coolant itself is preferably used as the heat storage medium. To charge the heat accumulator with heat, it is filled with the hot coolant, in particular coolant. The first cooler is designed to dissipate the waste heat from the drive engine contained in the coolant to the environment of the motor vehicle. The first cooling circuit can comprise further components, such as pumps for conveying the first coolant, valves, temperature sensors, and the like.

[0028] The second cooling circuit includes at least the battery, i.e., a traction battery, and a second cooler. The battery, which serves to store electrical energy to power an electric motor, is cooled by a second coolant, preferably also water-based. The heat contained in the second coolant is dissipated to the environment via the second cooler. The second cooling circuit may include additional components, such as pumps for conveying the second coolant, valves, temperature sensors, and the like.

[0029] As mentioned above, the first cooling circuit is fluidically coupled to the second cooling circuit. This means that the first coolant can be fed into the second cooling circuit. This allows the waste heat from the drive motor to be fed directly to the second cooling circuit without the need for a heat exchanger. Waste heat stored in the heat accumulator can also be fed directly to the second cooling circuit without the use of a heat exchanger. In this way, the waste heat stored in the heat accumulator can be used to preheat the battery even after the vehicle has been idle for an extended period, without the drive motor having to be started or already running.

[0030] According to a preferred embodiment, the heat accumulator has an electric heating means suitable for transferring heat to a heat storage medium contained in the heat accumulator. The heat storage medium can be the first coolant itself or other media known from the prior art (liquid, solid, gaseous) with high heat capacity that are suitable for storing heat. The electric heating means is preferably designed in the manner of an immersion heater and can be supplied with energy by means of the battery and / or an external power supply. The electric heating means heats up during operation and transfers the resulting heat energy to the heat storage medium.

[0031] A heat exchanger is integrated into the first cooling circuit, which dissipates the thermal energy contained in the first coolant as an alternative to the first radiator. The heat exchanger can be used to heat various vehicle components, preferably to heat the vehicle interior. In a preferred embodiment, the heat exchanger is connected in series with the heat accumulator and is arranged downstream of the first coolant with respect to the flow direction of the first coolant. A first three-way valve can be used to bypass the heat accumulator, so that the first coolant flows directly from the combustion engine to the heat exchanger.

[0032] The fluidic coupling between the first cooling circuit and the second cooling circuit is realized, as already described above, by means of a first and a second connecting line. The first connecting line is used to remove the first coolant from the first cooling circuit and is fluidically connected to it for this purpose. The first connecting line opens into a second, switchable three-way valve, which is integrated into the second cooling circuit. The fluidic coupling between the first and second cooling circuits can be opened or closed via the second three-way valve. By means of a second connecting line, the first coolant and / or a mixture of first and second coolant is removed from the second cooling circuit and fed to the first cooling circuit. In this way, the battery can be integrated into the first cooling circuit or connected to it.In this case, the first connecting line opens into the second cooling circuit immediately upstream of the battery in terms of flow direction, while the second connecting line is connected to the second cooling circuit immediately downstream of the battery.

[0033] The process-engineering aspect of the problem is solved by a method for operating a heat storage arrangement according to claim 4.

[0034] A method is shown for operating a heat storage arrangement for utilizing engine waste heat to preheat a battery designed as a traction battery of an electric or hybrid motor vehicle, comprising a first cooling circuit having at least one drive motor designed as an internal combustion engine, a heat accumulator, a first cooler, a heat exchanger and a first coolant circulating in the first cooling circuit, a second cooling circuit having at least one battery designed as a traction battery of an electric or hybrid motor vehicle, a second cooler and a second coolant circulating in the second cooling circuit, and having at least three operating modes, wherein in - in a first operating mode, a standard mode, the first coolant circulates through the drive motor and the first cooler, wherein the first coolant absorbs waste heat from the drive motor and releases it to the environment via the first cooler, - in a second operating mode, a charging mode, the first coolant circulates through the drive motor and the heat accumulator, wherein the first coolant absorbs the waste heat of the drive motor and releases it to the heat accumulator for storage, and which is characterized in that - in a third operating mode, a battery heating mode, the first coolant circulates only through the heat accumulator and the battery designed as a traction battery of an electric or hybrid vehicle, wherein the first coolant absorbs heat stored in the heat accumulator and releases it to the battery in order to preheat it.

[0035] The invention is therefore further directed to a method for operating a heat storage arrangement for utilizing engine waste heat to preheat a battery. This is a traction battery of an electric or hybrid motor vehicle. The heat storage arrangement has a first cooling circuit and a second cooling circuit according to the previously described embodiments. The first cooling circuit has at least one drive motor, a heat accumulator, a first radiator, and a first coolant. The first coolant circulates in the first cooling circuit. The second cooling circuit has at least one battery, a second radiator, and a second coolant, wherein the second coolant is preferably identical to the first coolant and circulates in the second cooling circuit. The cooling circuits can also have other components, such as pumps for conveying the coolants, valves, temperature sensors, and the like.As mentioned above, the heat storage arrangement can be operated in at least three different operating modes. In the first operating mode, which is the standard mode, the first coolant circulates through the drive motor and the first radiator. The standard mode serves solely to dissipate the waste heat generated in the drive motor. For this purpose, the first coolant passes through the drive motor and absorbs the waste heat generated during engine operation. The first coolant then passes through the first radiator, allowing the waste heat contained in the coolant to be released into the environment outside the motor vehicle.

[0036] The second operating mode, known as charging mode, is used to charge the heat storage unit with thermal energy. For this purpose, the first coolant flows through the drive engine and absorbs the waste heat generated during engine operation. The coolant is then directed to the heat storage unit to transfer the absorbed waste heat to it. For this purpose, the heat storage unit can either be fed with the hot coolant, or the waste heat contained in the coolant can be transferred via suitable means to a separate heat storage medium in the heat storage unit.

[0037] As already mentioned above, the heat storage arrangement has a third operating mode, a battery heating mode, for preheating the battery. In this operating mode, the first coolant circulates only through the heat storage medium and the battery. It does not pass through the drive motor. The first coolant absorbs the waste heat stored in the heat storage medium by either removing the coolant contained therein from the heat storage medium or by transferring the heat contained in the heat storage medium to the coolant. The first coolant is then removed from the first cooling circuit and fed into the second cooling circuit, where it passes through the battery. The heat contained in the first coolant is transferred to the battery, which can be preheated, for example for a cold start.After the first coolant has passed through the battery, it, or a mixture of the first and second coolants, is returned to the first cooling circuit and the heat accumulator integrated there. Advantageously, starting or operating the drive motor is not necessary to preheat the battery. The fluidic coupling between the first and second cooling circuits eliminates the need for complex components for thermal coupling, such as heat exchangers.

[0038] As mentioned above, the first cooling circuit has an additional heat exchanger. In a fourth operating mode, an interior heating mode, the first coolant can pass through the heat exchanger after passing through the drive motor to dissipate the waste heat absorbed by the drive motor. In particular, the waste heat can be used to heat the vehicle interior. Using a three-way valve, the heat accumulator can be selectively connected between the drive motor and the heat exchanger.

[0039] Alternatively, according to a fifth operating mode, a storage heat heating mode, the first coolant can only circulate through the heat accumulator and the heat exchanger. The drive motor is not passed through in this case. The first coolant extracts the stored heat from the heat accumulator and transfers it to the heat exchanger, in particular for heating the vehicle interior. After passing through the heat exchanger, the first coolant flows back to or into the heat accumulator. A process variant which combines the third operating mode with the fifth operating mode is particularly advantageous. The first coolant first flows through the heat accumulator, absorbs the heat stored therein and then passes through the heat exchanger. In this case, part of the heat contained in the first coolant can be transferred to the heat exchanger and used, for example, to heat the vehicle interior.After passing through the heat exchanger, the first coolant is fed into the second cooling circuit, which then flows through the battery. The residual heat contained in the coolant can be used to preheat the battery. The first coolant, or a mixture of the first and second coolants, is then returned to the first cooling circuit. In this way, both the passenger compartment and the battery of a motor vehicle, especially an electric or hybrid vehicle, can be preheated or heated to operating temperature before a cold start.

[0040] An optional embodiment of the method allows for the activation of a heat storage heating mode, whereby a heat storage medium contained in the heat storage device can be heated using an external energy supply. For this purpose, the heat storage device has an electric heating medium, for example in the form of an immersion heater, which can be operated either by the vehicle battery or by an external energy supply, such as a power connection. In this way, the heat storage medium of the heat storage device can be charged with sufficient thermal energy, even after any length of downtime or when the drive engine is not in operation, to preheat the interior and / or the battery of the vehicle during the next cold start. Fig. Figure 1 shows a schematic process flow diagram of a heat storage arrangement with a first and a second cooling circuit, as is known from the prior art. Further advantageous embodiments of the invention are disclosed in the subclaims and the following description of the figures. They show: Fig. 2 a schematic process flow diagram of a heat storage arrangement with a first and a second cooling circuit, in a first operating mode. Fig. 3 a schematic process flow diagram of the heat storage arrangement from Fig. 2 in a second operating mode, Fig. 4 a schematic process flow diagram of a heat storage arrangement from Fig. 2 in a third operating mode, Fig. 5 a schematic process flow diagram of a heat storage arrangement from Fig. 2 in a first operating mode with heat storage heating mode switched on.

[0041] In the different figures, identical parts are always provided with the same reference symbols, which is why they are usually only described once.

[0042] In Fig. 1 shows a schematic process flow diagram of a heat storage arrangement 100 according to the prior art. The heat storage arrangement 100 has a first cooling circuit 200 and a second cooling circuit 300. The first cooling circuit 200 is designed as a high-temperature cooling circuit for cooling a drive motor 210, preferably an internal combustion engine, and also has a radiator 220, a heat accumulator 230, and a heat exchanger 240. A thermostat 211 for regulating the temperature of a first coolant circulating in the first cooling circuit 200 is connected to the drive motor 210. The flow direction of the first coolant is shown by the arrows in the flow diagram. A first line section 212, a second line section 213, and a third line section 214 are connected to the thermostat 211. The first line section 212 flows into a first three-way valve 231.The heat accumulator 230 can be connected to the first cooling circuit 200 by means of the three-way valve 231. A first pump 232, preferably an electric water pump, is connected upstream of the heat accumulator 230 in terms of flow direction. In this embodiment, the heat accumulator 230 is implemented as an insulated container for the hot coolant. According to the illustrated circuit of the three-way valve 231, the first coolant flows directly into the heat exchanger 240 without first passing through the heat accumulator 230. The first coolant is returned to the drive motor 210 via a second pump 215, which is connected upstream of the drive motor 210.

[0043] The first coolant is fed to the first cooler 220 via the second line section 213. The first cooler 220 serves to dissipate the heat contained in the coolant to the environment. After passing through the cooler 220, the first coolant is in turn fed back to the drive motor 210 via the second pump 215. The first coolant, provided it has not yet absorbed sufficient heat, can be fed directly back to the combustion engine 210 via the third line section 214 via the second pump 215. The thermostat 211 is used to control the first coolant. Depending on the desired operating mode or the measured coolant temperature, the corresponding line sections 212, 213, or 214 are opened or closed, respectively. The second cooling circuit 300 is designed as a low-temperature cooling circuit for cooling a battery 310, preferably a traction battery of a hybrid vehicle.In addition to the battery 310, the second cooling circuit 300 has a second cooler 320, which is designed as a low-temperature cooler, and a third pump 340, preferably an electric water pump. A second coolant circulates within the second cooling circuit 300, with the arrows in the flow diagram indicating the flow direction of the second coolant. The second coolant absorbs the heat emitted by the battery 310 and passes through the second cooler 320 to dissipate the absorbed heat to the environment. It is known in the prior art to design the first cooler 220 and the second cooler 320, for example, as direct current heat exchangers, in order to create a thermal coupling between the first cooling circuit 200 and the second cooling circuit 300.

[0044] In the following, the terms “in front of” and “behind” refer to the flow direction of the coolant in question, as indicated by the arrows.

[0045] A schematic process flow diagram of a heat storage arrangement 100 is shown in Fig. 2. The heat storage arrangement 100 essentially corresponds to the heat storage arrangement known from the prior art according to Fig. 1, wherein the first cooler 220 and the second cooler 320 preferably have no thermal coupling. The first cooling circuit 200 additionally has a first connecting line 410, which opens into a second three-way valve 330. The second three-way valve 330 is integrated into the second cooling circuit 300 immediately upstream of the battery 310. With the appropriate position of the second three-way valve 330, the first coolant from the first cooling circuit 200 can be fed into the second cooling circuit 300. A second connecting line 420 is fluidly connected to the second cooling circuit 300 immediately downstream of the battery 310 for withdrawing the first coolant and / or a mixture of first and second coolants. The second connecting line 420 opens into the first cooling circuit 200 immediately upstream of the first pump 232.

[0046] According to Fig. Figure 2 shows a first operating mode, a standard mode. The first coolant circulates through the drive motor 210, absorbs its waste heat, passes through the thermostat 211, the second line section 213, and the first cooler 220, to release the heat contained in the coolant to the environment. The first coolant is then pumped back to the drive motor 210 by means of the second pump 215. Alternatively, the first coolant can be supplied to the first three-way valve 231 via the first line section 212. According to the illustrated position of the three-way valve 231, the first coolant is then supplied directly to the heat exchanger 240 and pumped to the drive motor 210 by means of the second pump 215.

[0047] In Fig. 3 is a schematic process flow diagram of a heat storage arrangement 100 according to Fig. 2. In this second operating mode, the first coolant, provided it has absorbed sufficient waste heat from the drive motor 210, is fed to the first line section 212 by means of the thermostat 211. The first three-way valve 231 is in the appropriate position to switch on the heat accumulator 230. The first coolant is fed to the heat accumulator 230 by means of the second pump 215 in order to charge it with the absorbed waste heat. It may also be useful for both pumps 232 and 215 to be activated simultaneously in order to increase the coolant flow to the heat accumulator 230. The first coolant then passes through the heat exchanger 240 in order to release any remaining heat to the vehicle interior. The cooled coolant is pumped back to the drive motor 210 by means of the second pump 215.

[0048] A third operating mode, a battery heating mode, is available in Fig. 4. The schematic process flow diagram shows a heat storage arrangement 100 according to Fig. 2. To preheat the battery 310, the second three-way valve 330 is in the appropriate position to fluidically connect the first connecting line 410 to the second cooling circuit 300. The first coolant is pumped from the heat accumulator 230 by means of the first pump 232, passes through the heat exchanger 240, and is then fed into the second cooling circuit 300 via the connecting line 410. The first coolant then passes through the battery 310 and transfers the heat contained in the first coolant to it. By means of the connecting line 420, which connects to the second cooling circuit 300 immediately after the battery 310, the first coolant and / or a mixture of the first and second coolants is fed back into the first cooling circuit 200 immediately before the first pump 232.The coolant circulates through the heat accumulator 230 and the battery 310 until, for example, a temperature sensor registers that the battery 310 has reached its operating temperature. Alternatively or optionally, part of the heat contained in the first coolant can be used to heat the vehicle interior via the heat exchanger 240. It is also conceivable to bypass the heat exchanger 240 using a bypass (not shown).

[0049] In Fig. 5 there is a heat storage arrangement 100, according to Fig.2, in a first operating mode. In addition, an optional heat storage heating mode is activated, in which an electrical heating element 500 is used to charge the heat storage device 230 with external energy. The electrical heating element 500 can, for example, be a simple immersion heater that is supplied with electrical energy by the battery 310, another vehicle battery, or an external power source. In particular, after a longer period of inactivity of the motor vehicle, for example after several days, the heat storage device 230 can be charged in this way by an external energy supply, and the stored energy can be used in the form of heat to preheat the battery 310 according to the third operating mode. List of reference symbols: 100 heat storage arrangement 200 first cooling circuit / high-temperature cooling circuit 210 drive motor 211 Thermostat 212 first line section 213 second line section 214 third line section 215 second pump 220 first cooler / high-temperature cooler 230 heat storage units 231 first three-way valve 232 first pump 240 heat exchangers 300 second cooling circuit / low-temperature cooling circuit 310 battery 320 second cooler / low-temperature cooler 330 second three-way valve 340 third pump 410 first connecting line 420 second connecting line 500 electric heating element

Claims

[1] Heat storage arrangement (100) designed to use engine waste heat to preheat a battery (310) designed as a traction battery of an electric or hybrid motor vehicle, with a first cooling circuit (200) which has at least - a drive motor (210) designed as an internal combustion engine and generating waste heat, wherein the waste heat is dissipated by means of a first coolant, - a heat accumulator (230) arranged to store the waste heat contained in the first coolant, - a heat exchanger (240) configured to utilize the waste heat contained in the first coolant, wherein the heat exchanger (240) is integrated into the first cooling circuit (200) by means of a first three-way valve (231), - a first cooler (220) for discharging the waste heat contained in the first coolant to the environment, and with a second cooling circuit (300) which has at least - a battery (310) designed as a traction battery of an electric or hybrid motor vehicle, arranged to store electrical energy for supplying an electric motor, wherein the battery (310) is cooled by means of a second coolant, - a second cooler (320) arranged to release heat contained in the second coolant to the environment, characterized bythat the first cooling circuit (200) is fluidically coupled to the second cooling circuit (300) by means of a first and a second connecting line (410, 420), wherein the first cooling circuit (200) has a first connecting line (410) arranged downstream of the heat exchanger (240), which opens into a second three-way valve (330) which is integrated into the second cooling circuit (300) immediately upstream of the battery (310), wherein a second connecting line (420) for removing the first coolant and / or a mixture of first and second coolant is fluidically connected to the second cooling circuit (300) immediately downstream of the battery (310), wherein the second connecting line (420) opens into the first cooling circuit (200) immediately upstream of the first pump (232),wherein the waste heat stored in the heat accumulator (230) can be used by means of the first coolant to preheat the battery (310) designed as a traction battery of an electric or hybrid motor vehicle. [2] Heat storage arrangement (100) according to claim 1, characterized by that the heat accumulator (230) has an electrical heating means (500) which is designed to release heat to a heat storage medium contained in the heat accumulator (230). [3] Heat storage arrangement (100) according to claim 1 or 2, characterized by that the heat exchanger (240) is designed to use the waste heat contained in the first coolant for a vehicle interior heating system. [4] Method for operating a heat storage arrangement (100) for utilising engine waste heat to preheat a battery (310) designed as a traction battery of an electric or hybrid motor vehicle according to one of the preceding claims, with a first cooling circuit (200) which has at least one drive motor (210) designed as an internal combustion engine, a heat accumulator (230), a first cooler (220), a heat exchanger (240) and a first coolant which circulates in the first cooling circuit (200), a second cooling circuit (300) which has at least one battery (310) designed as a traction battery of an electric or hybrid motor vehicle, a second cooler (320) and a second coolant which circulates in the second cooling circuit (300), and with at least three operating modes, wherein in - in a first operating mode, a standard mode, the first coolant circulates through the drive motor (210) and the first cooler (220), wherein the first coolant absorbs waste heat from the drive motor (210) and releases it to the environment via the first cooler (220), - in a second operating mode, a charging mode, the first coolant circulates through the drive motor (210) and the heat accumulator (230), wherein the first coolant absorbs the waste heat of the drive motor (210) and releases it to the heat accumulator (230) for storage, characterized by , that - in a third operating mode, a battery heating mode, the first coolant circulates only through the heat accumulator (230) and the battery (310) designed as a traction battery of an electric or hybrid vehicle, wherein the first coolant absorbs heat stored in the heat accumulator (230) and releases it to the battery (310) in order to preheat it. [5] Method according to claim 4, characterized by in a fourth operating mode, an interior heating mode, the first coolant circulates through the drive motor (210) and the heat exchanger (240), wherein the first coolant absorbs the waste heat of the drive motor (210) and releases it to the heat exchanger (240), in particular for heating a vehicle interior. [6] Method according to one of claims 4 or 5, characterized by in a fifth operating mode, a storage heat heating mode, the first coolant circulates only through the heat accumulator (230) and the heat exchanger (240), wherein the first coolant absorbs heat stored in the heat accumulator (230) and releases it to the heat exchanger (240), in particular for heating a vehicle interior. [7] Method according to one of claims 4 to 6, characterized bythat a heat storage heating mode can be switched on in order to supply heat to a heat storage medium contained in the heat accumulator (230) by means of an electrical heating means (500).

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