DE102016222080A1 - Heat cycle of an electric vehicle and method of operating the same - Google Patents

Abstract

The invention relates to a heat cycle of an electric vehicle, comprising an electric motor (5) designed to drive the electric vehicle, a battery (4) designed to provide energy for the electric motor (5), and a battery (4) and / or control unit Electric motor (5) formed power electronics (6), wherein the heat circuit (1) further comprises a housing (2) with a through-flow formed with a tempering fluid interior space (3), and the housing (2) has a thermal conductivity with the electric motor (5) connected, and in particular for the transmission of heat from the electric motor (5) to the interior (3) formed, first terminal (51), a thermally conductive to the power electronics (6) connected, and in particular for the transmission of heat from the power electronics (6 ) to the interior (3) formed second terminal (61), and further thermally conductively connected to the battery (4) en, and in particular for the transfer of heat from the interior (4) to the battery (4) formed, third terminal (41), wherein the battery (4) comprises a solid electrolyte.

Description

State of the art

The invention is based on a heat cycle of an electric vehicle according to the preamble of the independent claim. The subject matter of the present invention is also a method for operating a heat cycle of an electric vehicle.

In addition to the batteries used at the time of filing of the present application predominantly for electric vehicles with lithium-ion battery cells, which have a liquid organic electrolyte, possible post-lithium technologies based on battery cells with a solid electrolyte. In such battery cells whose performance is reduced below a temperature of 60 ° C. Furthermore, such battery cells should also have a temperature below 90 ° C for optimum operation. It is known from the prior art that a battery with a solid electrolyte has an additional heating element or a thermal insulation, in order to prevent falling below a lower temperature limit, in particular of 60 ° C.

The publication DE 42 26 781 A1 discloses a heat cycle of an electric vehicle, wherein the waste heat generated by a particularly operated at high temperature sodium-sulfur battery and an electric motor used to heat a passenger compartment.

The publication US Pat. No. 9,095,077 B2 discloses an arrangement for heating a battery with a solid electrolyte.

Disclosure of the invention

The heat cycle of an electric vehicle having the features of the independent claim has the advantage that a reliable temperature control of a solid electrolyte battery having by utilizing waste heat of other components of the electric vehicle is possible.

For this purpose, a heat cycle of an electric vehicle is provided. In this case, the heat cycle comprises an electric motor, which is designed to drive the electric vehicle, a battery, which is designed to provide energy for the electric motor, and power electronics, which is designed to control the battery and / or the electric motor. Furthermore, the heat cycle to a housing which has a formed for the passage of a tempering fluid interior. In this case, the housing has a thermally conductive connected to the electric motor first port, which is formed in particular for the transmission of heat from the electric motor to the interior of the housing. Furthermore, the housing has a thermally conductive connected to the power electronics second port, which is formed in particular for the transmission of heat from the power electronics to the interior of the housing.

Furthermore, the housing has a thermally conductive connected to the battery third terminal, which is designed in particular for the transfer of heat from the interior of the housing to the battery. According to the invention, the battery has a solid electrolyte.

This has the advantage that during operation of the electric vehicle resulting waste heat of the electric motor and the power electronics can heat the battery having a solid electrolyte.

The measures listed in the dependent claims advantageous refinements and improvements of the independent claim device are possible.

Under a solid electrolyte battery having a medium temperature battery should be understood, the operating range in the temperature range between 60 ° C and 120 ° C may be or between 60 ° C and 90 ° C or between 80 ° C and 120 ° C.

In particular, the battery having a solid electrolyte may have battery cells which have lithium as an anode, preferably in the form of a lithium foil, a Li alloy (eg Liln) or a thin layer Li on a metal substrate (eg Cu or Cu coated with Ni), as a cathode, a solid, such as a polymer, and having as a separator, a solid-based electrolyte, such as a ceramic or a polymer.

Due to limited conductivities of ions in such solid electrolyte, the battery should be operated in a described elevated temperature range to meet the power requirements of an electric vehicle.

According to a first advantageous development, the heat cycle also includes a fuel cell, which in particular has a polymer electrolyte. In this case, the housing has a thermally conductive connected to the fuel cell fourth port, which is designed in particular for the transmission of heat from the fuel cell to the interior of the housing.

As a result, the waste heat produced during the operation of a fuel cell can also heat the battery having a solid electrolyte.

In particular, designed as a hybrid or plug-in hybrid vehicles with a heat cycle with a fuel cell, for example, has a capacity of 35 kW, and having a solid electrolyte battery having, for example, a capacity of 35 kWh, a stationary operation of the fuel cell be made possible, whereby a simplification of their training and also their operation is possible. For this purpose, the battery having a solid electrolyte can provide additional power required, for example, for acceleration and / or uphill driving.

For a drive of the vehicle, in particular the fuel cell can deliver a continuous power and the battery having a solid electrolyte can deliver an additional power. In particular, the heat emitted by the fuel cell can also be used to heat the battery. By combining the fuel cell with the battery, the power output from the battery can be reduced because the fuel cell provides additional power. It is advantageously possible to charge the battery having a solid electrolyte in a rest phase of the vehicle and to dimension the battery according to the required range, for example for a range of one hundred kilometers. In addition, the fuel cell can provide additional energy to reach longer ranges without additional charging of the battery.

In this case, the fast starting capacity of the fuel cell is particularly useful for heating the battery at the beginning of a driving cycle and the battery can be used for a long-term power supply of the vehicle, whereby the requirements for the fuel cell can be reduced.

Overall, with the fuel cell so a higher range of the vehicle can be achieved. In addition, the battery can also provide high performance in the short term.

Overall, reduce the use of waste heat of the fuel cell for heating the battery, the requirements for the cooling system of the fuel cell.

According to a second advantageous development of the heat cycle further includes an internal combustion engine. In this case, the housing has a thermally conductive connected to the internal combustion engine fifth port, which is designed in particular for the transmission of heat from the internal combustion engine to the interior of the housing. As a result, the waste heat generated during operation of an internal combustion engine can also heat the battery having a solid electrolyte.

It is expedient if the heat cycle also has a delivery unit which is designed to convey a possible temperature-controlling fluid flowing through the interior. Preferably, the delivery unit is a pump and the tempering fluid flowing through the interior of the housing, a tempering, whereby a higher heat capacity of the heat transfer fluid compared to gases can ensure reliable transfer of heat between the individual elements of the heat cycle. Of course, it is also possible that the delivery unit is a compressor and the temperature control fluid flowing through the interior is a temperature control gas.

It is advantageous if the heat cycle continues to have an additional heating element. The additional heating element is designed to transmit additional heat to the interior, wherein the additional heating element may be, for example, a heating wire through which electric current flows.

It is particularly preferred if the heat circuit furthermore has a control unit connected to the delivery unit and / or with the additional heating element. The control unit is designed to control the volumetric flow which can be conveyed by the delivery unit through the interior of the housing and / or also the heat transferable to the interior from the additional heating element. In particular, this offers the advantage that by means of the control unit, the temperature of the battery having a solid electrolyte can be adjusted and in particular can be set in such a way that the temperature is in a temperature range between 60 ° and 90 °.

In particular, it can also be provided that housing walls not formed as thermally conductive connections and delimiting the interior of the housing have a heat-insulating coating in order to limit the heat transferred from the heat circuit to the environment in order not to affect surrounding components and, on the other hand, the housing to use existing heat in the interior for heating the battery.

Furthermore, the invention also relates to a method for operating a heat cycle according to the invention and in particular for controlling a Temperature of a battery with a solid electrolyte. For this purpose, a heat cycle just described is provided, which has at least one delivery unit, which is designed to convey a tempering fluid flowing through the interior and / or has at least one additional heating element, which is designed to transfer additional heat to the interior.

Furthermore, the heat cycle provided also has a control unit, which is connected in terms of regulation with the delivery unit and / or the additional heating element. In this case, the control unit is designed in such a way that the control unit controls the delivery unit and / or the additional heating element so that the battery with the solid electrolyte has a temperature of above 60 ° C and / or below 90 ° C.

In this case, the tempering fluid is preferably a tempering liquid, which has a higher heat capacity compared to a tempering gas, as already described.

Of course, the heat cycle provided for the process according to the invention can also be developed by all the advantageous developments shown in connection with the heat cycle according to the invention.

Overall, an embodiment of the invention of the heat cycle for an electric vehicle has the advantage that by integrating a plurality of required for the drive of the electric vehicle components, such as the electric motor, the power electronics, the fuel cell or the internal combustion engine, in a single heat cycle in addition to a reliable temperature the battery having a fortress electrolyte, the space required, the weight and the cost can be reduced in particular for a known from the prior art thermal insulation or a known additional heating element. This makes it possible to use the waste heat generated by the plurality of components required for the drive of the electric vehicle for the temperature control of the battery having a solid electrolyte. Furthermore, it is advantageously possible to reduce the number of required heat cycles, whereby the number of components of the electric vehicle can be reduced.

Furthermore, the invention also relates to an electric vehicle, which has a heat cycle according to the invention or a heat cycle, which is operated by a method according to the invention comprises.

Brief description of the drawings

Embodiments of the invention are illustrated in the single drawing and explained in more detail in the following description.

list of figures

• 1 schematically an embodiment of a heat cycle according to the invention.

The 1 schematically shows an embodiment of a heat cycle according to the invention 1 one in the 1 not shown electric vehicle.

The heat cycle 1 has a housing 2 on which of a first housing wall 21 , in particular an outer housing wall, and a second housing wall 22 , in particular an inner housing wall, is formed.

Furthermore, the housing has 2 an interior 3 on. It is from the 1 to recognize that the first housing wall 21 and the second housing wall 22 the interior 3 limit and in particular the interior 3 also fluid-tight with respect to an environment 23 of the heat cycle 1 to lock.

At this point it should be noted that the interior 3 can be flowed through by a tempering fluid.

The heat cycle 1 has a battery 4 on. The battery 4 has a solid electrolyte or a plurality of battery cells, each having a solid electrolyte.

The housing 2 has a thermal conductivity with the battery 4 connected third port 41 on. In particular, the third port 41 as a thermally conductive portion 43 the housing wall 21 be educated. The third connection is preferred 41 to a transfer of heat from the interior 3 to the battery 4 formed, which is indicated by the arrow 42 should be clarified.

The heat cycle 1 has an electric motor 5 on. In this case, the housing has 2 of the heat cycle 1 a first connection 51 on, which is thermally conductive with the electric motor 5 connected is. This is heat from the electric motor 5 to the interior 3 transferable, which is denoted by the reference numeral 52 indicated arrow should be clarified. Under a thermally conductive connection between the electric motor 5 and the first connection 51 of the housing 2 should be understood in particular that the first housing wall 21 of housing 2 at the point of the first connection 51 a thermally conductive formed section 53 and the electric motor 5 directly contacting on this thermally conductive trained section 53 is arranged. In particular, the electric motor 5 while another in the 1 Not shown heat cycle, which results in a transfer of the during operation of the electric motor 5 resulting waste heat to the first connection 51 is trained. By means of the thermally conductive formed section 53 the heat can then be transferred to the interior 3 be transmitted.

The heat cycle 1 has a power electronics 6 on. In this case, the housing has 2 of the heat cycle 1 a second connection 61 on, the thermally conductive with the power electronics 6 connected is. This is heat from the power electronics 6 to the interior 3 transferable, which is denoted by the reference numeral 62 indicated arrow should be clarified. Under a thermally conductive connection between the power electronics 6 and the second port 61 of the housing 2 should be understood in particular that the first housing wall 21 of the housing 2 at the location of the second port 61 a thermally conductive formed section 63 has and the power electronics 6 directly contacting on this thermally conductive trained section 63 is arranged. In particular, the power electronics 6 while another in the 1 Not shown heat cycle, which is a transfer of the during operation of the power electronics 6 resulting waste heat to the second connection 61 is trained. By means of the thermally conductive formed section 63 the heat can then be transferred to the interior 3 be transmitted.

The heat cycle 1 has, for example, a fuel cell 7 on. In this case, the housing has 2 of the heat cycle 1 a fourth connection 71 on, the thermally conductive with the fuel cell 7 connected is. This is heat from the fuel cell 7 to the interior 3 transferable, which is denoted by the reference numeral 72 indicated arrow should be clarified. Under a thermally conductive connection between the fuel cell 7 and the fourth connection 71 of the housing 2 should be understood in particular that the first housing wall 21 of the housing 2 in the place of the fourth connection 71 a thermally conductive formed section 73 has and the fuel cell 7 directly contacting on this thermally conductive trained section 73 is arranged. In particular, the fuel cell 7 while another in the 1 Not shown heat cycle, which is a transfer of the during operation of the fuel cell 7 resulting waste heat to the fourth connection 71 is trained. By means of the thermally conductive formed section 73 the heat can then be transferred to the interior 3 be transmitted. Preferably, the fuel cell 7 while a polymer electrolyte.

The heat cycle 1 has, for example, an internal combustion engine 8th on. In this case, the housing has 2 of the heat cycle 1 a fifth connection 81 on, the thermally conductive with the internal combustion engine 8th connected is. This is heat from the internal combustion engine 8th to the interior 3 transferable, which is denoted by the reference numeral 82 indicated arrow should be clarified. Under a thermally conductive connection between the internal combustion engine 8th and the fifth port 81 of the housing 2 should be understood in particular that the first housing wall 21 of the housing 2 at the location of the fifth port 81 a thermally conductive formed section 83 and the internal combustion engine 8th directly contacting on this thermally conductive trained section 83 is arranged. In particular, the internal combustion engine 8th while another in the 1 Have not shown heat cycle, resulting in a transfer of the during operation of the internal combustion engine 8th resulting waste heat to the fifth connection 81 is trained. By means of the thermally conductive formed section 83 the heat can then be transferred to the interior 3 be transmitted.

Furthermore, the shows 1 that the heat cycle 1 a conveyor unit 9 having. The conveyor unit 9 can be designed in particular as a pump or as a compressor. The interior 3 of the housing 2 is permeated by a tempering fluid, wherein the tempering fluid may be in particular a tempering or a tempering.

Furthermore, the in the 1 shown heat cycle 1 an additional heating element 10 on, by means of the additional heating element 10 an additional heat to the interior 3 can be transferred.

Preferably, they are not thermally conductive terminals of the housing 2 , So in particular not designed as thermally conductive sections 43 . 53 . 63 . 73 and 83 , trained and the interior 3 of the housing 2 delimiting housing walls on a heat-insulating coating or are advantageously formed of a heat-insulating material. To clarify the thermally conductive connections are formed 41 . 51 . 61 . 71 and 81 shown filled in black throughout.

Advantageously, the heat cycle comprises 1 also a control unit 11 , where the control unit 11 control technology by means of the connection shown 111 with the conveyor unit 9 is connected and further by means of the connection shown 112 control technology also with the additional heating element 10 connected is.

Here is the control unit 11 adapted to that of the conveyor unit 9 through the interior 3 of the housing 2 to control the delivered volume flow of the tempering and also of the additional heating element 10 to the interior 3 of the housing 2 to control transmitted heat.

This can be done by the control unit 11 for example by means of a connection 113 also with one on the battery 4 arranged temperature sensor 114 be connected to the temperature of the battery 4 to determine with a solid electrolyte and that of the conveyor unit 9 subsidized volume flow or that of the additional heating element 10 to the room 3 transferred heat to the measured temperature.

For example, the control unit 11 be formed in the way that at regular intervals by means of the temperature sensor 114 a value of the temperature of the battery 4 is determined and compared with a value of a target temperature. Since a temperature below 60 ° C is to be avoided, the setpoint temperature can be set to 65 ° C or 70 ° C, for example. Is the specific value of the temperature of the battery 4 less than the value of the specified setpoint temperature, the control unit switches 11 the conveyor unit 9 or increases the delivery capacity and / or switches the control unit 11 the additional heating element 10 or increases its performance. Is the specific value of the temperature of the battery 4 higher than the value of the specified setpoint temperature, the control unit switches 11 the conveyor unit 9 from or reduces their capacity and / or switches the control unit 11 the additional heating element 10 or reduce its performance. Such a method is used to heat the battery 10 , Which should be understood at this point to prevent the falling below a specified setpoint temperature.

Furthermore, the control unit 11 additionally be designed in such a way that these are the measured value of the temperature of the battery 4 compared with another value of a set temperature. If the measured value of the temperature is above the further value of the setpoint temperature, then the control unit can 11 on the one hand, the conveyor unit 9 and the additional heating element 10 switch off and / or one in the 1 not shown cooling circuit, which leads to a heat dissipation from the battery 4 is formed, turn on. This can also exceed the temperature of the battery 4 be prevented, for example, above 90 ° C. Such another setpoint value of the temperature may for example be advantageously 80 ° C or 85 ° C.

At this point it should be noted that the 1 merely intended to contribute to an understanding of the invention and is not limited to the embodiment shown, in particular, a different order of arrangement of the individual components is conceivable. Furthermore, for reasons of clarity, it is also not shown separately that the electric motor 5 designed to drive the electric vehicle that the battery 4 Energy for the electric motor 5 provides, and that the power electronics 6 the battery 4 and / or the electric motor 5 controls.

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 4226781 A1 [0003]
• US 9095077 B2 [0004]

Claims (10)

Heat cycle of an electric vehicle, comprising an electric motor (5) designed to drive the electric vehicle, a battery (4) designed to provide energy for the electric motor (5), and a controller (4) for controlling the battery (4) and / or the electric motor (5) trained power electronics (6), wherein the heat circuit (1) further comprises a housing (2) formed with a flow medium with a tempering fluid interior (3), and the housing (2) a thermally conductive with the electric motor (5) connected, and in particular for transmission of heat from the electric motor (5) to the interior (3) formed, first terminal (51), a thermally conductive with the power electronics (6) connected, and in particular for the transmission of heat from the power electronics (6) to the interior (3) formed second terminal (61), and further thermally conductive with the battery (4) connected, and in particular for practicing carrying heat from the interior (3) to the battery (4) formed third terminal (41), characterized in that the battery (4) comprises a solid electrolyte. Heat cycle according to one of the preceding claims, characterized in that the heat circuit (1) further comprises a, in particular a polymer electrolyte having fuel cell (7) and the housing (2) a thermally conductive with the fuel cell (7) connected, and in particular for the transmission of Heat from the fuel cell (7) to the interior (3) formed fourth terminal (71). Heat cycle according to one of the preceding claims, characterized in that the heat circuit (1) further comprises an internal combustion engine (8) and the housing (2) a thermally conductive with the internal combustion engine (8) connected, and in particular for the transmission of heat from the internal combustion engine (8 ) to the interior (3) formed fifth terminal (81). Heat cycle according to one of the preceding claims, characterized in that the heat circuit (1) further comprises a conveyor unit (9), in particular a pump, which is designed for conveying a the inner space (3) flowing through Temperierfluids. Heat cycle according to one of the preceding claims, characterized in that the heat circuit (1) further comprises an additional heating element (10) which is adapted to a transfer of additional heat to the interior (3). Heat cycle after at least one of the previous ones Claims 4 and 5 , characterized in that the heat circuit (1) further comprising a control unit (11) connected in terms of control with the conveying unit (9) and / or the additional heating element (10), which is adapted to the from the conveyor unit (9) through the interior (3) to control the volume (2) of the housing (2) and / or the heat transferred from the additional heating element (10) to the interior (3). Heat cycle according to one of the preceding claims, characterized in that not as thermally conductive terminals (41, 51, 61, 71, 81) formed and the interior (3) of the housing (2) delimiting housing walls have a heat-insulating coating. Method for controlling a temperature of a battery (4) with a solid electrolyte, wherein a heat circuit (1) according to at least one of Claims 1 to 7 is provided, wherein the heat circuit (1) has at least one conveying unit (9) which is designed to convey a tempering fluid flowing through the interior (3), and / or at least one additional heating element (10), which to a transfer of additional heat is formed on the interior (3), and further comprising a control technology with the conveyor unit (9) and / or the additional heating element (10) connected control unit (11), characterized in that the control unit (11) the conveyor unit (9) and / or the additional heating element (10) controls in such a way that the battery (4) has a temperature above 60 ° C and / or below 90 ° C. Method according to Claim 8 , characterized in that the tempering fluid is a temperature control liquid. Electric vehicle with a heating circuit (1) according to one of Claims 1 to 7 or one after Claim 8 or 9 operated heat cycle (1).

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