Temperature control system for electric vehicle

Abstract

To control the temperature of a battery with high responsiveness.SOLUTION: A temperature control system (100) for an electric vehicle includes a compressor (1) configured to compress a first coolant including CO2, a first heat exchanger (2a) configured to cool the first coolant, a cooling expansion valve (V1a, V1b) configured to expand the cooled first coolant, a coolant path (13b) configured to supply the expanded first coolant to an air conditioner (5) when cooling the air conditioner, a coolant path (12) configured to supply the expanded first coolant to a motor (4) when cooling the motor, a second heat exchanger (6a) configured to perform heat exchange between the first coolant and a second coolant including CO2 sealed inside a battery case (2b), and a fan (20) configured to circulate the second coolant between a periphery of a cell (6b) and the second heat exchanger. A refrigerant path (16b) for supplying the first refrigerant expanded by the expansion valve to the second heat-exchanger and a refrigerant path (141517) for supplying the first refrigerant to the compressor are provided.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a temperature control system for an electric vehicle. [Background technology]

[0002] Conventionally, air conditioning systems having a heat cycle circuit that operates with a refrigerant containing CO2 (hereinafter referred to as "CO2 refrigerant") have been known. Also under consideration are a technology in which the heat cycle circuit of an air conditioning system for a passenger compartment of an electric vehicle is thermally coupled to a battery to cool or heat the battery (for example, Patent Document 1), and a cooling system in which low-temperature CO2 is circulated inside a cooling unit to directly cool a vehicle drive motor, inverter, and battery that are sealed in individual packages to each other (for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-68348 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-107453 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the use of CO2 refrigerant in vehicle cabin air conditioning systems has been considered. In this case, it is conceivable that the CO2 refrigerant used in the thermal cycle circuit of the vehicle cabin air conditioning system could also be used to regulate the temperature of the motor and battery.

[0005] However, since the pressure of the CO2 refrigerant, which is reduced to a low temperature by an expansion valve in the thermal cycle circuit of an air conditioning system, is generally very high at around 5 MPa, if such high-pressure CO2 refrigerant is flowed around the battery cells to directly cool the cells, it becomes necessary to strengthen the battery case and cell structure, resulting in increased battery weight and manufacturing costs.On the other hand, if the cells inside the battery are indirectly cooled via a heat exchanger installed on the outside of the battery case by flowing high-pressure CO2 refrigerant through the heat exchanger, the temperature control response is slower than with the above-mentioned direct cooling, which increases the battery temperature fluctuation range and makes the battery more susceptible to deterioration due to the thermal cycle.

[0006] The present invention has been made to solve these problems, and has an object to provide a temperature control system for an electric vehicle that can control the temperature of a battery with high responsiveness using a CO2 refrigerant. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a temperature control system for an electric vehicle equipped with an air conditioning unit for performing air conditioning, a drive motor, and a battery with cells housed inside a battery case, the temperature control system including a compressor for compressing a first refrigerant containing CO2, a first heat exchanger for cooling the first refrigerant compressed by the compressor, a first expansion valve for expanding the first refrigerant cooled by the first heat exchanger, an air conditioning cooling path for supplying the first refrigerant expanded by the first expansion valve to the air conditioning unit when cooling the air conditioning unit, and a first expansion valve for supplying the first refrigerant expanded by the first expansion valve to the air conditioning unit when cooling the motor. The battery cooling system includes a motor cooling path that supplies the first refrigerant expanded by the expansion valve to the motor, a second heat exchanger that performs heat exchange between the first refrigerant and a second refrigerant containing CO2 sealed inside the battery case, a refrigerant circulation device that circulates the second refrigerant between the periphery of the cell and the second heat exchanger, a battery cooling path that supplies the first refrigerant expanded by the first expansion valve to the second heat exchanger when cooling the battery, and a recovery path that supplies the first refrigerant that has passed through the air conditioning unit, the first refrigerant that has passed through the motor, and the first refrigerant that has passed through the second heat exchanger to the compressor.

[0008] According to the present invention configured as described above, the air conditioning unit, the motor, and the battery are cooled using a common first refrigerant containing CO2, thereby enabling the overall temperature control system to be compact. Furthermore, the second refrigerant containing CO2 sealed inside the battery case is cooled by the first refrigerant in the second heat exchanger, and circulates between the periphery of the cells and the second heat exchanger, allowing the cells to be directly cooled using the low-pressure second refrigerant. This eliminates the need to increase the strength of the battery cell and case structures, enabling battery temperature control with high responsiveness without increasing battery weight or manufacturing costs.

[0009] In the present invention, preferably, the refrigerant circulation device has a fan provided inside the battery case, the second heat exchanger is provided on a wall surface of the battery case, and the fan circulates the second refrigerant between the periphery of the cells and the second heat exchanger inside the battery case.

[0010] According to the present invention configured as described above, the second refrigerant circulated inside the battery case by the fan exchanges heat with the first refrigerant as it flows along the second heat exchanger, thereby cooling or heating the battery, and then directly cooling or heating the battery cells as it flows around them. This allows for highly responsive temperature control of the battery without increasing the battery weight or manufacturing costs.

[0011] In the present invention, the refrigerant circulation device preferably has a second refrigerant path that fluidly connects the interior of the battery case and the second heat exchanger, and a pump that circulates the second refrigerant between the interior of the battery case and the second heat exchanger via the second refrigerant path.

[0012] According to the present invention configured as described above, the second refrigerant circulated between the inside of the battery case and the second heat exchanger by the pump exchanges heat with the first refrigerant as it passes through the second heat exchanger, thereby cooling or heating the cells, and then returning to the inside of the battery case and flowing around the cells, thereby enabling high-responsive temperature control of the battery without increasing the weight or manufacturing costs of the battery.

[0013] In the present invention, the temperature regulation system for an electric vehicle preferably includes a battery heating path that supplies a first refrigerant compressed by the compressor to the second heat exchanger when the battery is heated.

[0014] According to the present invention configured as described above, a high-temperature, high-pressure first refrigerant compressed by a compressor is supplied to the second heat exchanger, and the second refrigerant heated by the first refrigerant in the second heat exchanger directly heats the cells as it flows around them. This allows for highly responsive temperature control of the battery without increasing the battery weight or manufacturing costs.

[0015] In the present invention, the temperature control system for an electric vehicle preferably includes an air conditioning heating path that supplies refrigerant compressed by the compressor to the air conditioning unit when the air conditioning unit is heating.

[0016] According to the present invention configured as described above, the air conditioning unit can be heated by supplying high-temperature, high-pressure refrigerant compressed by the compressor to the air conditioning unit via the air conditioning heating path. [Effects of the Invention]

[0017] According to the temperature regulation system for an electric vehicle of the present invention, the temperature of the battery can be regulated with high responsiveness using CO2 refrigerant. [Brief explanation of the drawings]

[0018] [Figure 1]1 is a schematic configuration diagram of a vehicle to which a temperature control system for an electric vehicle according to an embodiment of the present invention is applied; [Figure 2] 1 is a schematic configuration diagram of a temperature control system for an electric vehicle according to an embodiment of the present invention; [Figure 3] 1 is a block diagram showing an electrical configuration of a temperature regulation system for an electric vehicle according to an embodiment of the present invention; [Figure 4] 3 is a flowchart of control executed by the temperature regulation system for an electric vehicle according to an embodiment of the present invention. [Figure 5] 1 is an explanatory diagram showing a PH diagram and a PT diagram of the thermal cycle of the air conditioner and the battery, and the flow of refrigerant, when there is a request for cooling of the air conditioner and a request for cooling of the battery, in a temperature control system for an electric vehicle according to an embodiment of the present invention. [Figure 6] 1 is an explanatory diagram showing a PH diagram and a PT diagram of the heating cycle of the air conditioner and the battery, and the flow of refrigerant, when there is a request for heating the air conditioner and a request for heating the battery, in a temperature control system for an electric vehicle according to an embodiment of the present invention. [Figure 7] FIG. 5 is a schematic configuration diagram of a temperature regulation system for an electric vehicle according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A temperature control system for an electric vehicle according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0020] [Overall configuration] First, the overall configuration of the temperature regulation system for an electric vehicle according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic configuration diagram of a vehicle to which the temperature regulation system for an electric vehicle according to this embodiment is applied.

[0021] 1, electric vehicle 200 includes a temperature control system 100 having a heat cycle circuit that operates with a refrigerant containing CO2, a motor 4 for driving electric vehicle 200, an air conditioner (air conditioning unit) 5 that conditions the air inside electric vehicle 200, and a battery 6 that supplies power to motor 4. Temperature control system 100 also includes mainly a compressor 1 for compressing the refrigerant and a heat exchanger 2 for exchanging heat with the refrigerant.

[0022] The temperature control system 100 circulates a CO2 refrigerant (hereinafter sometimes simply referred to as "refrigerant") as a natural refrigerant. Typically, CO2 refrigerant is a refrigerant containing refrigeration oil (oil) such as PAG and additives. To use such a CO2 refrigerant, the compressor 1 is configured to compress the refrigerant to a very high pressure. The motor 4 uses the refrigerant compressed by the compressor 1 and cooled by the heat exchanger 2 to cool the rotor and stator. Furthermore, the motor 4 is configured to lubricate the sliding bearing that supports the rotating shaft with the refrigerant. The refrigerant compressed by the compressor 1 or the refrigerant cooled by the heat exchanger 2 after compression is used for air conditioning in the air conditioner 5, as well as for cooling or heating the battery 6.

[0023] [Temperature control system configuration] Next, the temperature adjustment system 100 according to this embodiment will be specifically described with reference to Fig. 2. Fig. 2 is a schematic configuration diagram of the temperature adjustment system 100 according to this embodiment.

[0024] The temperature adjustment system 100 forms a heat cycle circuit that circulates the above-mentioned CO2 refrigerant as the first refrigerant, and in addition to the above-mentioned compressor 1 and heat exchanger 2, has refrigerant passages 11 to 17 through which the first refrigerant flows, cooling expansion valves (first expansion valves) V1a and V1b that expand the first refrigerant to reduce its pressure, and heating valves V1d and V1e, and a heat exchanger bypass control valve V1c that switches the refrigerant passages.

[0025] In this embodiment, the compressor 1 increases the pressure of the first refrigerant that has passed through the air conditioner 5, the motor 4, and the second heat exchanger 2b (described later) from pressure P2 to pressure P1. In one example, the pressure P1 is about 11 MPa, and the pressure P2 is about 5 MPa.

[0026] The motor 4 is cooled by the temperature adjustment system 100. Specifically, a first refrigerant is compressed by the compressor 1, passes through the first heat exchanger 2a via the refrigerant passage 11 to be cooled, and is further expanded by the cooling expansion valve V1a to be cooled, and is supplied to the motor 4 through the refrigerant passage (motor cooling path) 12. The first refrigerant supplied to the motor 4 cools the motor 4 by absorbing heat as it passes through the stator, rotor, bearings, etc. of the motor 4, returns to the compressor 1 via the refrigerant passage 14 (recovery path), and is compressed again.

[0027] The air conditioner 5 is cooled or heated by the temperature adjustment system 100. When the air conditioner 5 is cooling, the first refrigerant is compressed by the compressor 1, passes through the first heat exchanger 2a via the refrigerant passage 11 to be cooled, and then expands through the cooling expansion valve V1b to become cooler than the air inside the vehicle cabin, and is supplied to the air conditioner 5 through the refrigerant passage (air conditioning cooling path) 13b. The refrigerant supplied to the air conditioner 5 cools the air flowing into the vehicle cabin by absorbing heat as it passes through the vehicle cabin heat exchanger of the air conditioner 5, returns to the compressor 1 through the refrigerant passage 15 (recovery path), and is compressed again.

[0028] When the air conditioner 5 is heated, the first refrigerant is compressed by the compressor 1 to a high temperature and pressure, and is expanded by the temperature raising valve V1e through the heat exchanger bypass control valve V1c and the refrigerant passage 13a (air conditioning heating path). The first refrigerant, which is at a higher temperature than the air in the vehicle cabin, is supplied to the air conditioner 5. The first refrigerant supplied to the air conditioner 5 heats the air flowing into the vehicle cabin by dissipating heat as it passes through the vehicle cabin heat exchanger of the air conditioner 5, returns to the compressor 1 through the refrigerant passage 15 (recovery path), and is compressed again.

[0029] In this embodiment, the battery 6 includes a battery case 6a and cells 6b housed inside the battery case 6a. The battery case 6a is sealed, and a refrigerant containing CO2 is sealed inside the battery case 6a as a second refrigerant. A second heat exchanger 2b is provided on the wall of the battery case 6a, and the first refrigerant is supplied to the second heat exchanger 2b from a refrigerant passage 16a (battery heating path) or a refrigerant passage 16b (battery cooling path). This allows heat exchange between the first refrigerant and the second refrigerant inside the battery case 6a via the second heat exchanger 2b. Furthermore, a fan 20 (refrigerant circulation device) is provided inside the battery case 6a. The fan 20 circulates the second refrigerant inside the battery case 6a between the periphery of the cells 6b and the second heat exchanger 2b.

[0030] When cooling the battery 6, the first refrigerant is compressed by the compressor 1, passes through the first heat exchanger 2a via the refrigerant passage 11, is cooled, and further expands through the cooling expansion valve V1b to become cooler than the cells 6b. The first refrigerant supplied to the second heat exchanger 2b absorbs heat as it passes through the second heat exchanger 2b, thereby cooling the second refrigerant inside the battery case 6a. The first refrigerant returns to the compressor 1 via the refrigerant passage 17 (recovery passage), and is compressed again. The second refrigerant circulated inside the battery case 6a by the fan 20 is cooled by exchanging heat with the first refrigerant as it flows along the second heat exchanger 2b, and then absorbs heat from the cells 6b as it flows around them, thereby cooling the cells 6b.

[0031] Furthermore, when the battery 6 is heated, the first refrigerant is compressed by the compressor 1 and expanded by the heating valve V1d via the heat exchanger bypass control valve V1c and the refrigerant passage 13a (air conditioning heating path). At this time, the temperature of the first refrigerant is higher than that of the cells 6b. The first refrigerant expanded by the heating valve V1d is supplied to the second heat exchanger 2b through the refrigerant passage 16a (battery heating path). The first refrigerant supplied to the second heat exchanger 2b heats the second refrigerant inside the battery case 6a by dissipating heat as it passes through the second heat exchanger 2b, returns to the compressor 1 through the refrigerant passage 17 (recovery path), and is compressed again. The second refrigerant circulated inside the battery case 6a by the fan 20 is heated by exchanging heat with the first refrigerant as it flows along the second heat exchanger 2b, and then dissipates heat to the cells 6b as it flows around the cells 6b, heating them.

[0032] Next, the electrical configuration of the temperature adjustment system 100 according to this embodiment will be described with reference to Figures 2 and 3. Figure 3 is a block diagram showing the electrical configuration of the temperature adjustment system 100 according to this embodiment.

[0033] 3, the temperature adjustment system 100 has a control device 40 configured to perform various controls in the system. The control device 40 is configured by a computer including one or more processors 40a (typically a CPU) and memory 40b such as ROM and RAM that stores various programs (including basic control programs such as an OS and application programs that are started on the OS and realize specific functions) that are interpreted and executed on the processor 40a, and various data.

[0034] The temperature adjustment system 100 also includes a refrigerant temperature sensor 31 that detects the temperature of the refrigerant flowing through the refrigerant passages 11-17, a refrigerant pressure sensor 32 that detects the pressure of the refrigerant, a battery temperature sensor 33 that detects the temperature of the battery 6, a motor temperature sensor 34 that detects the temperature of the motor 4, an inside / outside air temperature sensor 35 that detects the air temperatures inside and outside the vehicle interior of the electric vehicle 200, and an air conditioning switch 36 that receives operation input to the air conditioner 5. A plurality of refrigerant temperature sensors 31 and refrigerant pressure sensors 32 can be provided at any location in the refrigerant passages 11-17.

[0035] Based on signals input from the above sensors 31 to 35 and the air conditioning switch 36, the control device 80 outputs control signals to the compressor 1, the fan 20, the cooling expansion valves V1a and V1b, the heat exchanger bypass control valve V1c, and the heating valves V1d and V1e, and controls them.

[0036] [control] Next, the control performed by the control device 40 in this embodiment will be described with reference to Fig. 4. Fig. 4 is a flowchart of the control performed by the temperature regulation system 100 for an electric vehicle according to the embodiment of the present invention.

[0037] 4 is repeatedly executed at predetermined intervals by the control device 40. Specifically, the processor 40a in the control device 40 reads out a program stored in the memory 40b and executes the program, thereby realizing the control shown in the flowchart of FIG.

[0038] When control is started, in step S1, the control device 40 acquires various information such as the detection values ​​detected by the above-mentioned sensors 31 to 35 and the operation value input to the air conditioning switch 36.

[0039] Next, in step S2, the control device 40 acquires a cooling / heating request for the air conditioner 5, i.e., a required value for the cooling capacity or heating capacity of the air conditioner 5 (e.g., the flow rate of refrigerant supplied to the air conditioner 5), based on the information acquired in step S1. For example, the required value for the cooling capacity or heating capacity of the air conditioner 5 is acquired according to the difference between the temperature set by the air conditioning switch 36 and the temperature inside the vehicle cabin.

[0040] Next, in step S3, the control device 40 acquires a cooling requirement for the motor 4, i.e., a required value of the cooling capacity for the motor 4 (e.g., the flow rate of the refrigerant supplied to the motor 4), based on the information acquired in step S1. For example, the required value of the cooling capacity for the motor 4 is acquired according to the difference between a preset reference temperature and the temperature of the motor 4 detected by the motor temperature sensor 34.

[0041] Next, in step S4, the control device 40 acquires a temperature adjustment request for the battery 6, i.e., a request for cooling or heating the battery 6, based on the information acquired in step S1. Specifically, when cooling of the battery 6 is required, for example, when the temperature of the battery 6 is higher than a preset reference temperature, the control device 40 acquires a request value for cooling the battery 6 (for example, a control value corresponding to opening the cooling expansion valve V1b, turning on the fan 20, operating the compressor 1, etc.). Also, when heating of the battery 6 is required, for example, when the temperature of the battery 6 is lower than a preset reference temperature, a request value for heating the battery 6 (for example, a control value corresponding to opening the heat exchanger bypass control valve V1c and the temperature raising valve V1d, turning on the fan 20, operating the compressor 1, etc.) is acquired.

[0042] Next, in step S5, the control device 40 controls the refrigerant flowing through the temperature adjustment system 100 based on the cooling / heating request for the air conditioner 5 acquired in step S2, the cooling request for the motor 4 acquired in step S3, and the temperature adjustment request for the battery 6 acquired in step S4 (step S5). That is, the control device 40 controls the operations of the compressor 1, fan 20, cooling expansion valves V1a and V1b, heat exchanger bypass control valve V1c, and temperature rise valves V1d and V1e so as to correspond to the required cooling or heating capacity of the air conditioner 5, the required cooling capacity of the motor 4, and the required cooling or heating capacity of the battery 6, respectively. After step S5, the control device 40 ends the control.

[0043] Next, an example of temperature control of the temperature adjustment system 100 according to an embodiment of the present invention will be described with reference to Figures 5 and 6. The upper parts of Figures 5 and 6 show PH diagrams and PT diagrams of the cooling or heating cycle of the air conditioner 5 and battery 6 in each control pattern, and the lower parts show the thermal cycle circuits of the temperature adjustment system 100 in each control pattern. In the thermal cycle circuits of Figures 5 and 6, solid lines indicate refrigerant passages through which refrigerant flows, and dashed lines indicate refrigerant passages through which refrigerant does not flow.

[0044] [Control 1] FIG. 5 is an explanatory diagram showing a PH diagram and a PT diagram of the cooling cycle of the air conditioner 5 and the battery 6 and the flow of refrigerant when there is a request for cooling of the air conditioner 5 and a request for cooling of the battery 6.

[0045] In the control 1 shown in FIG. 5, a heat cycle circuit for cooling the motor 4, a heat cycle circuit for cooling by the air conditioner 5, and a heat cycle circuit for cooling the battery 6 via the heat exchanger 2b are formed in the temperature adjustment system 100.

[0046] Of these, in the heat cycle circuit that cools the motor 4, the first refrigerant is compressed by compressor 1 to a high temperature and pressure (approximately 120°C, 11 MPa in the example of FIG. 5), passes through refrigerant passage 11 and first heat exchanger 2a where it is cooled (approximately 30°C in the example of FIG. 5), and is further isenthalpily expanded by cooling expansion valve V1a to a low temperature (approximately 20°C, 5 MPa in the example of FIG. 5) and is supplied to motor 4 through refrigerant passage (motor cooling path) 12. The first refrigerant supplied to motor 4 cools motor 4 by absorbing heat as it passes through the stator, rotor, bearings, etc. of motor 4, and then returns to compressor 1 through refrigerant passage 14 (recovery path) where it is compressed again.

[0047] In the heat cycle circuit that cools the air conditioner 5, the first refrigerant is compressed by the compressor 1 to a high temperature and high pressure (approximately 120°C and 11 MPa in the example of FIG. 5, point A2 on the PH and PT diagrams), passes through the first heat exchanger 2a via the refrigerant passage 11, is cooled (approximately 30°C in the example of FIG. 5, point A3 on the PH and PT diagrams), and is isoenthalpily expanded by the cooling expansion valve V1b to a low temperature (approximately 20°C and 5 MPa in the example of FIG. 5, point A4 on the PH and PT diagrams), and is supplied to the air conditioner 5 through the refrigerant passage (motor cooling path) 13b. The first refrigerant supplied to the air conditioner 5 absorbs heat as it passes through the passenger compartment heat exchanger of the air conditioner 5, thereby cooling the air flowing into the passenger compartment, and then returns to the compressor 1 via the refrigerant passage 15 (recovery path) (approximately 30°C and 5 MPa in the example of FIG. 5, point A1 on the PH and PT diagrams) and is compressed again.

[0048] In the thermal cycle circuit that cools the battery 6, the first refrigerant is compressed by the compressor 1 to a high temperature and high pressure (approximately 120°C and 11 MPa in the example of FIG. 5, point A2 on the PH and PT diagrams). The first refrigerant passes through the first heat exchanger 2a via the refrigerant passage 11 and is cooled (approximately 30°C in the example of FIG. 5, point A3 on the PH and PT diagrams). The first refrigerant is isoenthalpily expanded by the cooling expansion valve V1b to a temperature lower than that of the cells 6b (approximately 20°C and 5 MPa in the example of FIG. 5, point A4 on the PH and PT diagrams). The first refrigerant is then supplied to the second heat exchanger 2b via the refrigerant passage 16b (battery cooling path). The first refrigerant supplied to the second heat exchanger 2b absorbs heat as it passes through the second heat exchanger 2b, thereby cooling the second refrigerant inside the battery case 6a. The first refrigerant then returns to the compressor 1 via the refrigerant passage 17 (recovery path) and is compressed again (approximately 30°C and 5 MPa in the example of FIG. 5, point A1 on the PH and PT diagrams). The second refrigerant (0.1 MPa in the example of Figure 5) circulated inside the battery case 6a by the fan 20 is cooled by exchanging heat with the first refrigerant as it flows along the second heat exchanger 2b, and then cools the cells 6b by absorbing heat from the cells 6b as it flows around them.

[0049] [Control 2] FIG. 6 is an explanatory diagram showing a PH diagram and a PT diagram of the heating cycle of the air conditioner 5 and the battery 6 and the flow of refrigerant when there is a request for heating the air conditioner 5 and a request for heating the battery 6.

[0050] 6, a heat cycle circuit for cooling the motor 4, a heat cycle circuit for cooling the air conditioner 5, and a heat cycle circuit for cooling the battery 6 via the heat exchanger 2b are formed in the temperature adjustment system 100. Of these, the heat cycle circuit for cooling the motor 4 is the same as in Control 1.

[0051] In the heat cycle circuit that heats the air conditioner 5, the first refrigerant is compressed by the compressor 1 to a high temperature and pressure (approximately 120°C and 11 MPa in the example of FIG. 6, point A2 on the PH and PT diagrams), and is expanded by the temperature raising valve V1e through the heat exchanger bypass control valve V1c and the refrigerant passage 13a (air conditioning heating path). The first refrigerant, which is at a higher temperature than the air in the vehicle cabin (approximately 60°C and 5 MPa in the example of FIG. 6, point A3 on the PH and PT diagrams), is supplied from the refrigerant passage (air conditioning heating path) 13a to the air conditioner 5. The first refrigerant supplied to the air conditioner 5 heats the air flowing into the vehicle cabin by dissipating heat as it passes through the interior heat exchanger of the air conditioner 5, returns to the compressor 1 through the refrigerant passage 15 (recovery path) (approximately 30°C and 5 MPa in the example of FIG. 6, point A1 on the PH and PT diagrams), and is compressed again.

[0052] In the heat cycle circuit that heats the battery 6, the first refrigerant is compressed by the compressor 1 to a high temperature and high pressure (approximately 120°C and 11 MPa in the example of FIG. 6, point A2 on the PH and PT diagrams), and is expanded by the heating valve V1d through the heat exchanger bypass control valve V1c and the refrigerant passage 13a (air conditioning heating path). At this time, the temperature of the first refrigerant is higher than that of the cell 6b (approximately 60°C and 5 MPa in the example of FIG. 6, point A3 on the PH and PT diagrams). The first refrigerant expanded by the heating valve V1d is supplied to the second heat exchanger 2b from the refrigerant passage 16a (battery heating path). The first refrigerant supplied to the second heat exchanger 2b dissipates heat as it passes through the second heat exchanger 2b, thereby heating the second refrigerant inside the battery case 6a, and returns to the compressor 1 through the refrigerant passage 17 (recovery path) (approximately 30°C, 5 MPa in the example of FIG. 6, point A1 on the PH diagram and PT diagram), where it is compressed again. The second refrigerant circulated inside the battery case 6a by the fan 20 is heated by exchanging heat with the first refrigerant as it flows along the second heat exchanger 2b, and then dissipates heat to the cells 6b as it flows around them, thereby heating the cells 6b.

[0053] In addition to the above-described Control 1 and Control 2, the temperature adjustment system 100 can also execute controls when there is a request for heating to the air conditioner 5 and a request for cooling to the battery 6, when there is no request for heating or cooling to the air conditioner 5 (i.e., the air conditioner 5 is OFF) and a request for cooling or heating to the battery 6, and when there is a request for dry heating to the air conditioner 5 and a request for cooling or heating to the battery 6. In these controls, as with the above-described Control 1 and Control 2, by forming a thermal cycle circuit corresponding to the temperature adjustment request to the air conditioner 5 and the temperature adjustment request to the battery 6, control according to the temperature adjustment request can be executed.

[0054] [Second embodiment] Next, a temperature regulation system 100 according to a second embodiment will be described with reference to Fig. 7. Fig. 7 is a schematic configuration diagram of the temperature regulation system 100 according to the second embodiment.

[0055] In the temperature adjustment system 100 of the second embodiment, the configuration of the refrigerant circulation device that circulates the second refrigerant between the periphery of the cell 6b and the second heat exchanger 2b is different from that of the above embodiment shown in FIG.

[0056] Specifically, in the second embodiment, no fan 20 is provided inside the battery case 6a, as shown in Fig. 7. Furthermore, the second heat exchanger 2b does not necessarily have to be provided on the wall surface of the battery case 6a.

[0057] On the other hand, in the second embodiment, the refrigerant circulation device is provided with a refrigerant passage 22 (second refrigerant path) that fluidly connects the interior of the battery case 6a and the second heat exchanger 2b, and a pump 21 that circulates the second refrigerant between the interior of the battery case 6a and the second heat exchanger 2b via the refrigerant passage 22. That is, the first refrigerant and the second refrigerant are supplied to the second heat exchanger 2b, and are configured to exchange heat with each other inside the second heat exchanger 2b.

[0058] When cooling the battery 6, the first refrigerant is compressed by the compressor 1, passes through the first heat exchanger 2a via the refrigerant passage 11, is cooled, and further expands through the cooling expansion valve V1b, becoming cooler than the cells 6b. The first refrigerant is then supplied to the second heat exchanger 2b via the refrigerant passage 16b (battery cooling path). The first refrigerant supplied to the second heat exchanger 2b absorbs heat as it passes through the second heat exchanger 2b, thereby cooling the second refrigerant flowing through the second heat exchanger 2b, returns to the compressor 1 via the refrigerant passage 17 (recovery path), and is compressed again. The second refrigerant, which is pumped by the pump 21 and circulates between the inside of the battery case 6a and the second heat exchanger 2b, is cooled by exchanging heat with the first refrigerant as it passes through the second heat exchanger 2b, and then returns to the inside of the battery case 6a and absorbs heat from the cells 6b as it flows around them, thereby cooling the cells 6b.

[0059] Furthermore, when the battery 6 is heated, the first refrigerant is compressed by the compressor 1 and expanded by the heating valve V1d through the heat exchanger bypass control valve V1c and the refrigerant passage 13a (air conditioning heating path). At this time, the temperature of the first refrigerant is higher than that of the cells 6b. The first refrigerant expanded by the heating valve V1d is supplied to the second heat exchanger 2b through the refrigerant passage 16a (battery heating path). The first refrigerant supplied to the second heat exchanger 2b dissipates heat as it passes through the second heat exchanger 2b, thereby heating the second refrigerant flowing through the second heat exchanger 2b, and then returns to the compressor 1 through the refrigerant passage 17 (recovery path) and is compressed again. The second refrigerant, which is pumped by the pump 21 and circulates between the inside of the battery case 6a and the second heat exchanger 2b, is heated by exchanging heat with the first refrigerant as it passes through the second heat exchanger 2b. Then, as it returns to the inside of the battery case 6a and flows around the cells 6b, it dissipates heat to the cells 6b, thereby heating the cells 6b.

[0060] The temperature regulation control and thermal cycle circuit of the temperature regulation system 100 according to the second embodiment can be configured in the same manner as those described in the above embodiments.

[0061] [Action and effect] Next, the effects of the temperature regulation systems for electric vehicles according to the above-described embodiment and the second embodiment will be described.

[0062] According to the temperature adjustment system 100 of this embodiment, a common first refrigerant containing CO2 is used to cool the air conditioner 5, the motor 4, and the battery 6, allowing the overall configuration of the temperature adjustment system 100 to be compact. Furthermore, the second refrigerant containing CO2 sealed inside the battery case 6a is cooled by the first refrigerant in the second heat exchanger 2b, and circulates between the periphery of the cells 6b and the second heat exchanger 2b, allowing the cells 6b to be directly cooled using the low-pressure second refrigerant. Therefore, there is no need to increase the structural strength of the cells 6b of the battery 6 or the battery case 6a, and the temperature of the battery 6 can be adjusted with high responsiveness without increasing the weight of the battery 6 or increasing manufacturing costs.

[0063] Furthermore, the second refrigerant circulated inside the battery case 6a by the fan 20 exchanges heat with the first refrigerant as it flows along the second heat exchanger 2b, thereby cooling or heating the cells 6b, and then directly cooling or heating the cells 6b as it flows around the cells 6b. This allows the temperature of the battery 6 to be regulated with high responsiveness without increasing the weight of the battery 6 or the manufacturing costs.

[0064] Furthermore, the second refrigerant circulated between the inside of the battery case 6a and the second heat exchanger 2b by the pump 21 exchanges heat with the first refrigerant as it passes through the second heat exchanger 2b, thereby cooling or heating the cells 6b, and then returning to the inside of the battery case 6a and flowing around the cells 6b, thereby directly cooling or heating the cells 6b. This allows the temperature of the battery 6 to be regulated with high responsiveness without increasing the weight of the battery 6 or the manufacturing cost.

[0065] Furthermore, the high-temperature, high-pressure first refrigerant compressed by the compressor 1 is supplied to the second heat exchanger 2b, and the second refrigerant heated by the first refrigerant in the second heat exchanger 2b can directly heat the cells 6b as it flows around the cells 6b. This allows the temperature of the battery 6 to be regulated with high responsiveness without increasing the weight of the battery 6 or the manufacturing cost.

[0066] Furthermore, the high-temperature, high-pressure refrigerant compressed by the compressor 1 is supplied to the air conditioner 5 via the refrigerant passage 13a, thereby heating the air conditioner 5. [Explanation of symbols]

[0067] 1 Compressor 2 Heat exchanger 2a 1st heat exchanger 2b Second heat exchanger 4 motors 5. Air Conditioning 6 Battery 6a Battery Case 6b Cell 11~17 Refrigerant passage 20 fans 21 Pump 22 Refrigerant passage 31 Refrigerant temperature sensor 32 Refrigerant pressure sensor 33 Battery Temperature Sensor 34 Motor temperature sensor 35 Inside and outside air temperature sensor 36 Air conditioning switch 40 Control device 100 Temperature Control System 200 Electric Vehicles V1a, V1b cooling expansion valve V1c Heat Exchanger Bypass Control Valve V1d, V1e temperature rise valve

Claims

1. A temperature control system for an electric vehicle including an air conditioning unit for performing air conditioning, a drive motor, and a battery having cells housed inside a battery case, CO 2 a compressor for compressing a first refrigerant including: a first heat exchanger that cools the first refrigerant compressed by the compressor; a first expansion valve that expands the first refrigerant cooled by the first heat exchanger; an air conditioning cooling path that supplies the first refrigerant expanded by the first expansion valve to the air conditioning unit when cooling the air conditioning unit; a motor cooling path that supplies the first refrigerant expanded by the first expansion valve to the motor when cooling the motor; The first refrigerant and the CO sealed inside the battery case 2 a second heat exchanger for exchanging heat with a second refrigerant containing a refrigerant circulation device that circulates the second refrigerant between the periphery of the cell and the second heat exchanger; a battery cooling path that supplies the first refrigerant expanded by the first expansion valve to the second heat exchanger when cooling the battery; a recovery path that supplies the first refrigerant that has passed through the air conditioning unit, the first refrigerant that has passed through the motor, and the first refrigerant that has passed through the second heat exchanger to the compressor; A temperature control system for an electric vehicle.

2. the refrigerant circulation device has a fan provided inside the battery case, the second heat exchanger is provided on a wall surface of the battery case, the fan circulates the second refrigerant between the periphery of the cells and the second heat exchanger inside the battery case. The temperature control system for an electric vehicle according to claim 1 .

3. The refrigerant circulation device includes a second refrigerant path that fluidly connects the interior of the battery case and the second heat exchanger, and a pump that circulates the second refrigerant between the interior of the battery case and the second heat exchanger via the second refrigerant path. The temperature control system for an electric vehicle according to claim 1 .

4. 4. The temperature control system for an electric vehicle according to claim 1, further comprising: a battery heating path that supplies the first refrigerant compressed by the compressor to the second heat exchanger when the battery is heated.

5. 4. The temperature control system for an electric vehicle according to claim 1, further comprising an air conditioning heating path that supplies the first refrigerant compressed by the compressor to the air conditioning unit when the air conditioning unit is heated.

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