DE102018203540A1 - Air conditioning device of a motor vehicle with a heat pump and method for operating such a heat pump - Google Patents

Abstract

The invention relates to an air conditioning device of a motor vehicle with a heat pump, wherein the heat pump has a battery heat exchanger (6) which is thermally coupled to a battery of the motor vehicle, wherein the battery heat exchanger (6) in an operating mode of the heat pump as a condenser or gas cooler to give off heat to the battery. Furthermore, the invention relates to a method for operating such an air-conditioning device (1, 1 ', 1 ").

Description

The invention relates to an air conditioning device of a motor vehicle, in particular a hybrid vehicle or an electric vehicle, with a heat pump, which enables the heating of a battery, in particular a traction battery of the motor vehicle. Furthermore, the invention relates to a method for operating a heat pump of such an air conditioning device.

In the field of automotive development, the focus is currently on efficient electrification of the powertrain of motor vehicles. In particular, electrification requires the use of high-voltage batteries (HV batteries).

To maximize the performance of a battery and to protect the battery from aging and damage, the temperature of the battery should be kept within a temperature range of 15 ° C to 30 ° C. Therefore, high voltage batteries are usually cooled during operation to avoid overheating. In cold environments it may also be necessary to heat the battery.

For this reason, water cooling of the high-voltage battery in conjunction with a heater, for example a so-called PTC heater (PTC - positive temperature coefficient), is often used in the water circuit. So revealed the DE 10 2015 103 032 A1 For example, a thermal management system for a vehicle having a series of refrigerant circuits. One of the coolant circuits is used to cool the vehicle battery and also integrates a battery heater, such as a 12V electric heater, to warm the coolant before flowing through the battery. A similar heating and cooling system also describes the DE 10 2013 114 307 A1 ,

When using a heater, in addition to the battery, the entire water circuit must be heated, which reduces the efficiency of this heating method. Furthermore, the installation of this heater leads to additional space requirements and extra weight in the vehicle.

Alternatively, heating of the battery may be provided by electrical heating elements, e.g. Heated mats, wires and the like, take place. Electrical heating elements inside the battery, however, cause additional costs in the already very cost-sensitive component high-voltage battery.

All of these heating methods are often powered from the high-voltage battery itself with energy. The energy required for this purpose is then no longer available for the driving function and the vehicle range is thus reduced.

The object of the present invention is to provide an air-conditioning device and a method for operating a heat pump of the air-conditioning device which at least partially overcome the abovementioned disadvantages.

This object is achieved by the air conditioning device according to the invention according to claim 1 and the inventive method for operating a heat pump according to claim 10.

According to a first aspect, the invention relates to an air conditioning device of a motor vehicle with a heat pump, wherein the heat pump has a battery heat exchanger, which is thermally coupled to a battery of the motor vehicle, wherein the battery heat exchanger in an operating mode of the heat pump as a condenser or gas cooler for dispensing of heat to the battery acts.

According to a second aspect, the invention relates to a method for operating a heat pump of an air conditioning device of a motor vehicle, wherein actuators of the heat pump are set so that a battery heat exchanger of the heat pump, which is thermally coupled to a battery of the motor vehicle, in a first mode of operation as a condenser or gas cooler acts to deliver heat to the battery and in a second mode of operation acts as an evaporator for receiving heat from the battery.

Further advantageous embodiments of the invention will become apparent from the subclaims and the following description of preferred embodiments of the present invention.

The present invention relates to an air conditioning device of a motor vehicle, for example a hybrid or electric vehicle, each having an electric drive machine. The air conditioning device comprises a heat pump, which is designed in particular as a refrigerant circuit. The refrigerant circuit is preferably flowed through by a refrigerant, for example 2,3,3,3-tetrafluoropropene (R1234yf), carbon dioxide (R744) or another refrigerant. The heat pump has a battery heat exchanger, which is thermally coupled to a battery of the motor vehicle. The battery may be a high-voltage battery of the motor vehicle, for example a traction battery of the motor vehicle for feeding the electric drive machine of the motor vehicle.

The battery heat exchanger acts in an operating mode of the heat pump, in particular at least in a first operating mode of the heat pump, as a condenser (condenser) or gas cooler for discharging heat to the battery, in particular as a refrigerant condenser. The battery thus forms a heat sink of the heat pump, at least in the first operating mode.

The battery can thus be heated by a heat pump in the vehicle. The battery heat exchanger is preferably integrated directly into the refrigerant circuit and not included in a coupled cooling circuit. Since the heat pump can usually be operated with a COP (coefficient of performance)> 1, such a heating function can be more efficient than a purely electrical heating according to the prior art.

In some embodiments, the battery heat exchanger in a further operating mode of the heat pump, in particular at least in a second operating mode of the heat pump, act as an evaporator for absorbing heat from the battery, in particular as a refrigerant evaporator. Depending on requirements, in particular as a function of an outside temperature and a load on the battery, the battery can thus be heated or cooled via the same refrigerant circuit, which can be dispensed with additional heating elements for heating the battery.

In some embodiments, the heat pump, an actuator, such as a shut-off valve, having arranged so that refrigerant flows through the battery heat exchanger in a first position of the actuator so that the battery heat exchanger acts as a condenser or gas cooler, and that the refrigerant flows through the battery heat exchanger in a second position of the actuator so that the battery heat exchanger acts as an evaporator. Preferably, the actuator is at least in the first operating mode of the heat pump in its first position and at least in the second operating mode of the heat pump in its second position, wherein the switching of the actuator between the first and the second operating mode results in a flow reversal.

For example, the shut-off valve may be arranged upstream of a compressor of the heat pump and a node, via which the compressor with an outdoor heat exchanger, for example, a condenser for receiving heat from the environment, is connected. In the first position of the shut-off valve, in which the shut-off valve is closed, the heated refrigerant after passing through an indoor heat exchanger for dissipating heat to an interior of the motor vehicle (vehicle interior) via a first open flow branch directly to the heating of the battery by the battery Heat exchanger and then flow through the outdoor heat exchanger. In the first position of the shut-off valve, a second flow branch, via which the heated refrigerant can also flow into the battery heat exchanger, may be closed. In the second position of the shut-off valve, in which the shut-off valve is opened, the refrigerant can flow through the battery heat exchanger after flowing through an indoor heat exchanger for releasing heat to the vehicle interior for cooling the battery via the second flow branch, which is now open and then flowing the refrigerant heated by the battery heat exchanger directly to the compressor through the opened shut-off valve. In the second position of the shut-off valve, the first flow branch is preferably closed. By adjusting the shut-off valve and the first valve in the first flow branch and the second valve in the second flow branch so a reversal of the flow direction through the battery heat exchanger, ie preferably in the battery or a battery chiller, occur, so that in the first position of the shut-off valve in the battery, a further heat dissipation occurs after in both cases, the inner heat exchanger was first flowed through.

In some embodiments, the heat pump may further include a compressor and an indoor heat exchanger for directly or indirectly releasing heat to an interior of the motor vehicle. Preferably, the heat pump may be a heat pump, which is integrated in particular in the motor vehicle, primarily serves the cabin heater and in addition for heating the battery, in particular the high-voltage battery, is available. The compressor may have an electric motor, which may preferably be supplied with electrical energy by an electrical system, for example a 12V vehicle electrical system or a 400V vehicle electrical system. The indoor heat exchanger may include a water-refrigerant heat exchanger for transmitting heat to a refrigerant circuit coupled to the refrigerant circuit, a refrigerant-to-air heat exchanger that outputs heat directly from the refrigerant to the indoor heat exchanger, or another indoor heat exchanger his. The internal heat exchanger can be arranged in the refrigerant circuit in the flow direction after the compressor and in front of the battery heat exchanger. Thus, the heated refrigerant can first flow through the inner heat exchanger, which absorbs a portion of the heat and the refrigerant cools something, and then flow through the battery heat exchanger with a lower temperature.

In some embodiments, the heat pump may be configured such that the refrigerant releases heat in the indoor heat exchanger until a temperature of the refrigerant reaches the boiling temperature of the refrigerant, and then the refrigerant flows through the battery heat exchanger at the boiling temperature. So it comes to a two-part heat dissipation. Since the refrigerant may be overheated by compression by means of the compressor, i. may have a temperature above the boiling point, it can in the indoor heat exchanger as long as heat until the temperature reaches the boiling point. The refrigerant then flows through the battery heat exchanger at the boiling point. Thus, overheating of the battery can be prevented and the battery can be uniformly heated because the boiling temperature is maintained during the heat release for a certain time.

In some embodiments, the heat pump may include a controllable expansion device disposed between the indoor heat exchanger and the battery heat exchanger, wherein the controllable expansion device is adapted to reduce a pressure in a region of the battery heat exchanger. The expansion device may be a valve, preferably a valve with a variable cross-sectional opening. The valve may be configured to reduce the pressure in the refrigerant circuit, resulting in a reduction in the boiling temperature of the refrigerant. As a result, on the one hand, heating at lower temperatures and evaporation of the refrigerant at lower temperatures can be made possible.

The controllable expansion device may be designed to reduce the pressure in a region of the battery heat exchanger so that a boiling point of the refrigerant in a range between 0 ° C and 30 ° C, preferably in a range of 20 ° C to 30 ° C. , lies. It can thus come to a two-stage heat dissipation, wherein the internal heat exchanger gas cooling and optionally condensing at a high pressure level, especially at a condensation temperature in a range of 40 ° C to 80 ° C, for example, at a condensation temperature of 60 ° C, heat and releases the battery heat exchanger then after condensation condensing at a low pressure at a condensation temperature in the range of 20 ° C to 30 ° C, for example, at a condensation temperature of 25 ° C, evenly emits heat to the battery.

In some embodiments, the heat pump may alternatively be configured such that the refrigerant flows from the indoor heat exchanger to the battery heat exchanger without being actively throttled. Preferably, in this case between the indoor heat exchanger and the battery heat exchanger no relaxation member and thus no active throttling provided. A pressure level in the region of the internal heat exchanger and the battery heat exchanger can thus be substantially the same and vary only due to pressure losses in the lines. For example, a pressure difference between the area of the indoor heat exchanger and the area of the battery heat exchanger can be less than 15 bar. If the refrigerant is R1234yf, the pressure difference may be less than 2 bar and, if the refrigerant is R744, the pressure difference may be less than 10 bar. It can thus come to a quasi-two-part isobaric heat output, the inner heat exchanger gas cooling and partially condensing emits heat with a detectable temperature difference and the battery heat exchanger then gives off condensing heat without significant temperature difference to the battery. Thus, even without throttling, a uniform heating of the battery can be made possible.

In some embodiments, the heat pump may further include an indoor air-refrigerant heat exchanger disposed in the refrigerant circuit of the heat pump such that it is at least in the first operating mode of the heat pump in parallel to the battery heat exchanger with release of heat from the refrigerant is flowed through. Thus, the refrigerant flow through the heat pump can be used both for effective heating of the interior of the motor vehicle and for heating the battery.

The heat pump may also dispense with an indoor heat exchanger and an indoor air-refrigerant heat exchanger. In this case, the battery heat exchanger can be coupled directly behind the compressor in the refrigerant circuit and there is a one-stage heat transfer to the battery without simultaneous heating of the cabin. However, so the warming of the vehicle interior can not be realized in the same refrigerant circuit and also the heating temperature and the homogeneity of the heating can be made difficult.

In some embodiments, the battery heat exchanger may be a phase change structure disposed in and / or on the battery or a heat exchanger for introducing heat into a cooling circuit through which the battery flows, for example, a battery chiller. In a conversion of a refrigerant evaporative cooling for the battery evaporator structures are often introduced in the battery interior, in which a direct evaporation of the Refrigerant the vehicle air conditioning is done. In this way, a cooling effect for the battery can be displayed without additional liquid cooling circuit. This refrigerant evaporator can now be used directly in the heat pump operation of the air conditioning also for heating the battery. Alternatively, the heat can also be introduced via a separate heat exchanger (chiller) in a water circuit, which flows through the battery. Preferably, a water circuit is used here, which is already provided for a battery cooling anyway.

The heat pump may have further actuators and other controllable relaxation organs. The actuators and controllable relaxation organs of the heat pump can be actuated by means of electrical actuators, which are supplied via the electrical system of the motor vehicle with electrical energy.

In summary, the present air-conditioning device enables a very efficient heating of the battery by a heat pump function with COP> 1, a sharing of heating capacity on the cabin and battery, which takes into account the interior comfort, and an adjustable temperature level for the battery by two-stage operation of the heat pump that optimal operating conditions can be adjusted for the battery (temperature level and homogeneity).

Furthermore, the present invention relates to a method for operating a heat pump of an air conditioning device of a motor vehicle, for example a heat pump, as described in detail above. According to the method, actuators of the heat pump are set so that a battery heat exchanger of the heat pump, which is thermally coupled to a battery of the motor vehicle, acts as a condenser or gas cooler for discharging heat to the battery in a first operating mode and in a second operating mode Evaporator acts to absorb heat from the battery.

In some embodiments, in the first mode of operation, a pressure in a region of the battery heat exchanger may be reduced so that a boiling temperature of the refrigerant is in a range between 0 ° C and 30 ° C, preferably in a range of 20 ° C to 30 ° C , lies. For this purpose, a controllable expansion element, which is arranged between an internal heat exchanger and the battery heat exchanger, are adjusted accordingly. It can thus be made possible a two-stage heat release, wherein the internal heat exchanger gas cooling and optionally condensing at a high pressure level, especially at a condensation temperature in a range of 40 ° C to 80 ° C, for example, at a condensation temperature of 60 ° C, heat and releases the battery heat exchanger then after condensation condensing at a low pressure at a condensation temperature in the range of 20 ° C to 30 ° C, for example, at a condensation temperature of 25 ° C, evenly emits heat to the battery.

An entry point, in particular a relationship between pressure, moisture content and temperature, of the refrigerant in the battery heat exchanger, ie in the battery or the battery chiller, can be adjusted by a heat output at the internal heat exchanger and an opening cross section of the controllable expansion device. Ideally, this point should come to lie on a dew line (condensation curve) in an enthalpy pressure diagram, for example, a logarithmic enthalpy pressure diagram, that as much heat as possible at the temperature level of the battery heat exchanger through the phase change of the refrigerant the battery can be registered without the refrigerant undergoes a Temperauränderung.

The heat pump can still be operated in other operating modes, wherein the battery heat exchanger acts as an evaporator for absorbing heat from the battery or is not used.

• 1 schematisch ein erstes Ausführungsbeispiel einer Klimatisierungsvorrichtung eines Kraftfahrzeugs;
• 2 eine erste Beziehung zwischen Enthalpie und Druck während eines Strömungszyklus des Kältemittels;
• 3 eine zweite Beziehung zwischen Enthalpie und Druck während eines Strömungszyklus des Kältemittels;
• 4 schematisch ein zweites Ausführungsbeispiel einer Klimatisierungsvorrichtung eines Kraftfahrzeugs; und
• 5 schematisch ein zweites Ausführungsbeispiel einer Klimatisierungsvorrichtung eines Kraftfahrzeugs.

Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings. It shows:

• 1 schematically a first embodiment of an air conditioning device of a motor vehicle;
• 2 a first relationship between enthalpy and pressure during a flow cycle of the refrigerant;
• 3 a second relationship between enthalpy and pressure during a flow cycle of the refrigerant;
• 4 schematically a second embodiment of an air conditioning device of a motor vehicle; and
• 5 schematically a second embodiment of an air conditioning device of a motor vehicle.

1 shows a first embodiment of an air conditioning device 1 of a motor vehicle. The air conditioning device 1 includes a refrigerant circuit 2 which forms a heat pump. The refrigerant circuit 2 contains a compressor 3 , an interior condenser 4 , a first relaxation valve 5a and a second expansion valve 5b , a battery heat exchanger 6 , a first shut-off valve 7a , a second shut-off valve 7b and a third shut-off valve 7c and an outdoor evaporator 8th ,

The compressor 3 Compresses warmed refrigerant such as 2,3,3,3-tetrafluoropropene (R1234yf) or carbon dioxide (R744) released from the outdoor evaporator 8th or from the battery heat exchanger 6 to the compressor 3 flows. The interior condenser 4 moving in the direction of flow after the compressor 3 is arranged and removes heat from the heated and compressed refrigerant and to an air flow 9 , which flows in the direction of a passenger cabin of the motor vehicle, emits and heats the passenger cabin. The first relaxation valve 5a is downstream of the interior condenser 4 arranged and serves to reduce the pressure of the refrigerant. By reducing the pressure, the boiling temperature of the refrigerant also decreases.

At a first node 10 moving in the flow direction after the first expansion valve 5a is located, the refrigeration cycle is divided into a first branch 11 and a second branch 12 on. In the first branch 11 is the first shut-off valve 7a , a second node 13 and the second shut-off valve 7b intended. The first branch 11 flows into a third node 14 where the first branch is 11 with the second branch 12 united. In the second branch 12 is the third shut-off valve 7c , a fourth node 15 , the second expansion valve 5b and the outdoor evaporator 8th intended. The battery heat exchanger 6 is between the second node 13 and the fourth node 15 arranged so that the refrigerant from the second node 13 or the fourth node 15 to the battery heat exchanger 6 can flow.

In a first operating mode of the air conditioning device 1 is the first shut-off valve 7a opened and the second shut-off valve 7b and the third shut-off valve 7c closed. As a result, the refrigerant flows from the interior condenser 4 through the first expansion valve 5a and along the first branch 11 through the first shut-off valve 7a in the battery heat exchanger 6 that in the first expansion valve 5a throttled refrigerant extracts more heat and thus heats the battery of the motor vehicle. The battery heat exchanger 6 acts in the first mode of operation thus as a condenser and thus as a further heat sink of the air conditioning device.

The refrigerant that overheats in the interior condenser 4 occurred is by the release of heat in the interior condenser 4 approximately to the boiling temperature at the pressure in the interior condenser 4 , here about 60 ° C, cooled. In the first expansion valve 5a the pressure was reduced and the boiling point of the refrigerant lowered to about 25 ° C. At this temperature, the battery is then heated evenly.

Subsequently, the refrigerant flows over the fourth node 15 through the second expansion valve 5b , which further lowers the pressure, to the outdoor evaporator 8th , The outdoor evaporator 8th absorbs heat from the ambient air to heat the refrigerant at low pressure at which the boiling temperature is lowered.

2 shows by way of example a first relationship between enthalpy H and pressure during a flow cycle of the refrigerant through the refrigerant circuit, wherein the pressure axis is scaled logarithmically. It rises in the compressor 3 the enthalpy with increasing pressure, as at A indicated. Then it comes in the interior condenser 4 at a first pressure p ₁ to an enthalpy delivery at unchanged pressure, as indicated at B. In the first relaxation valve 5a the pressure is lowered without changing the enthalpy, as indicated at C. Then it comes in the battery heat exchanger 6 , which is operated as a condenser, at a second pressure p ₂ that is lower than the first pressure p ₁ is to give an enthalpy at unchanged pressure, as in D indicated. Subsequently, in the second expansion valve 5b the pressure on a third pressure p ₃ which is lower than the second pressure p ₂ is, lowered, as indicated at E. In the outdoor evaporator 8th it comes at the third pressure to an enthalpy increase, as indicated at F.

It thus comes to a two-stage heat dissipation, wherein gas-cooling and optionally condensing at a high pressure level heat in the interior condenser 4 is discharged and then at low pressure level, the battery is heated. This makes it possible to reliably heat the battery at a suitable temperature and uniformly. Alternatively, the first expansion valve may be fully opened or omitted. In this case, the refrigerant flows unthrottled through the first shut-off valve 7a and the second node 13 in the battery heat exchanger 6 , Again, the battery heat exchanger acts 6 as a condenser, which gives off heat to the battery, and forms another heat sink of the air conditioning device 1 ,

The refrigerant that overheats in the interior condenser 4 occurred is by the release of heat in the interior condenser 4 cooled, causing a temperature difference between in the interior condenser 4 inflowing refrigerant and from the interior condenser 4 escaping refrigerant comes. Subsequently, the refrigerant flows through the battery heat exchanger at a reduced temperature 6 , where the Temperature remains substantially constant. At this temperature, the battery is then heated evenly. The further course of the flow of the refrigerant corresponds to the course described above by the second expansion valve 5b and the outdoor evaporator 8th ,

3 shows by way of example a second relationship between enthalpy and pressure during a flow cycle of the refrigerant through the refrigerant circuit, wherein the pressure axis is scaled logarithmically. It rises in the compressor 3 the enthalpy with increasing pressure, as at A ' indicated. Then it comes in the interior condenser 4 at a first pressure p ₁ to an enthalpy release at unchanged pressure, as in B ' indicated. Then it comes in the battery heat exchanger 6 Operated as a condenser, at the first pressure to a further Enthalpieabgabe, as in C ' indicated. Subsequently, in the second expansion valve 5b the pressure on a second pressure p ₂ that is lower than the first pressure p ₁ is, lowered, as at D ' indicated. In the outdoor evaporator 8th it comes at the second pressure to an enthalpy increase, as in e ' indicated.

So it comes to a two-stage heat dissipation, heat is given gas cooling and partially condensing in the interior (with temperature difference) and then condensing (without significant temperature difference) heat is discharged into the battery.

In a second operating mode of the air conditioning device 1 is the first shut-off valve 7a closed and the second shut-off valve 7b and the third shut-off valve 7c open. The refrigerant flows over the second branch 12 over the fourth node 15 to the battery heat exchanger 6 which extracts heat from the battery and cools the battery. The battery heat exchanger 6 acts in the second operating mode thus as an evaporator and forms a cold trap of the air conditioning device 1 ,

4 shows a second embodiment of an air conditioning device 1' of a motor vehicle. The air conditioning device 1' is based on the principle of the air conditioning device 1 of the first embodiment. In addition, the air conditioning device includes 1' an interior heat exchanger 16 in the second branch 12 before the fourth node 15 is arranged and shared with the interior condenser 4 an air conditioner (shown as dashed box) forms. Instead of the outside vaporizer 6 is an outdoor heat exchanger 6 ' provided, which can act both as an evaporator and as a condenser. Furthermore, in the second branch 12 before the fourth node 15 a third expansion valve 5c provided and between the fourth node and the battery heat exchanger 6 ' a fourth expansion valve 5d ,

The air conditioning device 1' also includes a third branch 17 , which is at a fifth node 18 that is between the interior condenser 4 and the first expansion valve 5a is located, branches off and at a sixth node 19 that is between the outdoor heat exchanger 8th' located in the second branch 12 In the branch there is a fourth shut-off valve 7d ,

The second branch 12 will after the second expansion valve 5b through an internal heat exchanger 19 that is between the third node 14 and the compressor 3 is arranged, and then in the outdoor heat exchanger 8th' directed. Between the sixth node 19 and the third node 14 is a fifth shut-off valve 7e arranged and between the third node 14 and the internal heat exchanger 20 is still a collector 21 intended.

In the first mode of operation, the first shut-off valve 7a and the fifth stop valve 7e opened while the second shut-off valve 7b and the fourth shut-off valve 7d are closed. As in the first embodiment, the refrigerant flows through the interior condenser 4 , happens the battery heat exchanger 6 and then flows through the outdoor heat exchanger 6 ' , As described in detail with regard to the first exemplary embodiment, two-part heat emission occurs in the second exemplary embodiment as well, so that the battery can be heated uniformly at moderate temperatures.

In the second mode of operation, the first shut-off valve 7a , the fourth shut-off valve 7d and the fifth stop valve 7e as well as the second expansion valve 5b closed and the second shut-off valve 7b open. The refrigerant flows through the interior condenser 4 and the interior heat exchanger 16 and becomes in the fourth expansion valve 5d throttled. The throttled refrigerant reaches the battery heat exchanger 6 and absorbs heat from the battery to cool it. The cooled refrigerant continues to flow through the second shut-off valve 7b , the collector 21 and the internal heat exchanger 20 to the compressor 3 ,

In a third mode of operation, the first shut-off valve 7a , the second shut-off valve 7b and the fourth shut-off valve 7d closed and the fifth shut-off valve 7e open. In this mode of operation, the refrigerant flows into the interior condenser 4 and the interior heat exchanger 16 , is in the second expansion valve 5b throttled and flows under heat absorption the outside Heat exchanger 8th' , The battery heat exchanger 6 In this operating mode, the refrigerant does not flow through and the battery is neither cooled nor heated accordingly.

In a fourth mode of operation, the first shut-off valve 7a , the second shut-off valve 7b and the fourth shut-off valve 7d opened and the fifth shut-off valve 7e as well as the first relaxation valve 5a closed. The refrigerant flows through the interior condenser 4 , the third branch 17 and gets to the outdoor heat exchanger 8th' which extracts heat from the refrigerant and releases it to the environment. The cooled refrigerant is passed through the second expansion valve 5b throttled and parallel through the interior heat exchanger 16 or the battery heat exchanger 6 directed. In this mode of operation, the battery heat exchanger functions 6 as an evaporator to cool the battery. At the same time, the passenger cabin is air-conditioned.

In a fifth operating mode, the first shut-off valve 7a and the fifth stop valve 7e as well as the first relaxation valve 5a closed and the second shut-off valve 7b and the fourth shut-off valve 7d open. The refrigerant flows through the interior condenser 4 , the third branch 17 and gets to the outdoor heat exchanger 8th' which extracts heat from the refrigerant and releases it to the environment. The cooled refrigerant is passed through the second expansion valve 5b throttled and through the battery heat exchanger 6 directed. In this mode of operation, the battery heat exchanger functions 6 again as an evaporator to cool the battery.

5 shows a third embodiment of an air conditioning device 1" of a motor vehicle. The air conditioning device 1" is based on the principle of the air conditioning device 1' of the second embodiment. Instead of the interior condenser 4 is a water-refrigerant heat exchanger 4 ' provided, the heat to a coolant circuit 22 emits. The coolant circuit 22 includes an electrical heating element 23 , a heating heat exchanger 24 that with the interior heat exchanger 16 the air conditioner (shown as dashed box) of the motor vehicle, and a pump 25 ,

The operating modes of the air conditioning device 1" are analogous to the first to fifth operating modes of the second embodiment.

LIST OF REFERENCE NUMBERS

1, 1 ', 1 "

Air conditioning device

2

Refrigerant circuit

3

compressor

4

Interior condenser

4 '

Water-refrigerant heat exchanger

5a, 5b, 5c, 5d,

expansion valve

6

Battery heat exchanger

7a, 7b, 7c, 7d, 7e

shut-off valve

8th

Outdoor evaporator

8th'

Outdoor heat exchanger

9

airflow

10, 13, 14, 15, 18, 19

hubs

11, 12, 17

Branches of the refrigerant circuit

16

Interior heat exchanger

20

internal heat exchanger

21

collector

22

Coolant circuit

23

electric heating element

24

Heating heat exchanger

25

pump

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015103032 A1 [0004]
• DE 102013114307 A1 [0004]

Claims (11)

Air conditioning device of a motor vehicle with a heat pump, wherein the heat pump has a battery heat exchanger (6) which is thermally coupled to a battery of the motor vehicle, wherein the battery heat exchanger (6) in an operating mode of the heat pump as a condenser or gas cooler for discharging heat acts on the battery. Air conditioning device according to Claim 1 wherein the battery heat exchanger (6) acts as an evaporator for receiving heat from the battery in a further operating mode of the heat pump. Air conditioning device according to Claim 2 wherein the heat pump comprises an actuator (7b) which is arranged so that refrigerant flows through the battery heat exchanger (6) in a first position of the actuator (7b) so that the battery heat exchanger (6) acts as a condenser or gas cooler , And that the refrigerant flows through the battery heat exchanger (6) in a second position of the actuator (7b) so that the battery heat exchanger (6) acts as an evaporator. Air conditioning device according to one of the preceding claims, wherein the heat pump further comprises a compressor (3) and an internal heat exchanger (4, 4 ') for discharging heat to an interior of the motor vehicle, wherein the internal heat exchanger (4, 4') in Flow direction after the compressor (3) and in front of the battery heat exchanger (6) is arranged. Air conditioning device according to Claim 4 wherein the heat pump is designed so that the refrigerant in the indoor heat exchanger (4, 4 ') releases heat until a temperature of the refrigerant reaches the boiling point of the refrigerant, and then the refrigerant at the boiling temperature by the battery heat exchanger (6 ) flows. Air conditioning device according to Claim 4 or 5 wherein the heat pump comprises a controllable expansion element (5a) which is arranged between the inner heat exchanger (4, 4 ') and the battery heat exchanger (6), wherein the controllable expansion element (5a) is adapted to a pressure in one To reduce the area of the battery heat exchanger (6). Air conditioning device according to Claim 4 or 5 wherein the heat pump is configured such that the refrigerant flows from the indoor heat exchanger (4, 4 ') to the battery heat exchanger (6) without being actively throttled thereby. Air conditioning device according to one of the preceding claims, wherein the heat pump further comprises a further interior air-refrigerant heat exchanger (16) which is arranged so that it is flowed through in parallel to the battery heat exchanger (6) with the release of heat from the refrigerant , Air conditioning device according to one of the preceding claims, wherein the battery heat exchanger (6) is a phase change structure, which is arranged in and / or on the battery, or a heat exchanger for introducing heat into a cooling circuit flowing through the battery. A method for operating a heat pump of an air conditioning device (1, 1 ', 1 ") of a motor vehicle, wherein actuators (7b) of the heat pump are set so that a battery heat exchanger (6) of the heat pump, which is thermally coupled to a battery of the motor vehicle , acts as a condenser or gas cooler in a first mode of operation to deliver heat to the battery and, in a second mode of operation, acts as an evaporator to absorb heat from the battery. Method according to Claim 10 wherein, in the first operating mode, a pressure in a region of the battery heat exchanger (6) is reduced so that a boiling temperature of the refrigerant is in a range between 0 ° C and 30 ° C.

Images