Battery temperature control device

Abstract

To appropriately control the temperature of a low-voltage battery and the temperature of a high-voltage battery.SOLUTION: Provided is a battery temperature control apparatus, including: a high-voltage battery installed in a vehicle; a low-voltage battery installed in the vehicle; a first temperature control system capable of controlling a temperature of the low-voltage battery using air supplied from outside the vehicle; and a second temperature control system that is different from the first temperature control system and can control a temperature of the high-voltage battery using a heat medium circulating within the vehicle. The second temperature control system includes: a first heat exchanger capable of exchanging heat between the high-voltage battery and the heat medium; and a second heat exchanger capable of exchanging heat between the low-voltage battery and the heat medium. The temperature of the low-voltage battery is controlled using the heat medium supplied to the second heat exchanger.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a battery temperature control device.

Background Art

[0002] For example, Patent Document 1 discloses a technique for adjusting the temperature of each battery in a vehicle including a high-voltage battery and a low-voltage battery. In such Patent Document 1, the temperature of the high-voltage battery is adjusted by a refrigerant (LLC), and the temperature of the low-voltage battery is adjusted by air cooling.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An appropriate temperature range in which the charge and discharge operations can be properly performed is predetermined for the low-voltage battery and the high-voltage battery. Here, for example, it is assumed that the low-voltage battery is composed of a battery with a narrow appropriate temperature range. In this case, depending on the temperature of the air for adjusting the temperature of the low-voltage battery and the heat generation state of the low-voltage battery, it may not be possible to sufficiently adjust the temperature of the low-voltage battery by air cooling.

[0005] Therefore, it is conceivable to adjust the temperature of the low-voltage battery by the refrigerant that adjusts the temperature of the high-voltage battery. However, since the usage states of the low-voltage battery and the high-voltage battery are different, the temperatures of the low-voltage battery and the high-voltage battery change independently of each other. Then, for example, the high-voltage battery may be overcooled outside the appropriate temperature range by cooling the low-voltage battery, and it may not be possible to appropriately adjust the temperature of the low-voltage battery and the temperature of the high-voltage battery.

[0006] Therefore, the present invention aims to provide a battery temperature control device capable of appropriately adjusting the temperature of low-voltage batteries and high-voltage batteries. [Means for solving the problem]

[0007] To solve the above problems, a battery temperature control device according to one embodiment of the present invention is provided. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Control device and Equipped with, The aforementioned second temperature control system is, A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by supplying the heat transfer medium to the second heat exchanger. Occasionally, The control device is One or more processors, One or more memory connected to the processor, It has, The aforementioned processor, If the temperature of the low-voltage battery is higher than the upper limit temperature of the appropriate temperature range, the temperature of the air supplied to the first temperature control system is compared with the temperature of the low-voltage battery. If the temperature of the air supplied to the first temperature control system is lower than the temperature of the low-voltage battery, the first temperature control system will perform cooling of the low-voltage battery. If the temperature of the air supplied to the first temperature control system is equal to or greater than the temperature of the low-voltage battery, the second temperature control system will perform cooling of the low-voltage battery. Execute the process that includes this. To solve the above problems, a battery temperature control device according to one embodiment of the present invention is provided. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Control device and Equipped with, The aforementioned second temperature control system is, A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The control device is One or more processors, One or more memory connected to the processor, It has, The first temperature control system includes an air heater that heats the air supplied to the first temperature control system. The aforementioned processor, If the temperature of the low-voltage battery is lower than the lower limit temperature of the appropriate temperature range, the temperature of the heated air, which is the air heated by the air heater, is compared with the temperature of the low-voltage battery. If the temperature of the heated air is higher than the temperature of the low-voltage battery, the first temperature control system will perform heating of the low-voltage battery. If the temperature of the heated air is below the temperature of the low-voltage battery, the second temperature control system will perform heating of the low-voltage battery. Execute the process that includes this. To solve the above problems, a battery temperature control device according to one embodiment of the present invention is provided. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Control device and Equipped with, The aforementioned second temperature control system is, A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The control device is One or more processors, One or more memory connected to the processor, It has, The first temperature control system includes an air heater that heats the air supplied to the first temperature control system. The aforementioned processor, When the temperature of the low-voltage battery is within the appropriate temperature range, the temperature of the mixture of heated air, which is air heated by the air heater among the air supplied to the first temperature control system, and unheated air, which is air supplied to the first temperature control system that has not been heated by the air heater, is derived. To determine whether the temperature of the mixture is within the appropriate temperature range for the low-voltage battery, If the temperature of the mixture is within the appropriate temperature range for the low-voltage battery, the mixture is supplied to the low-voltage battery to maintain the temperature of the low-voltage battery within the appropriate temperature range. Execute the process that includes this. To solve the above problems, a battery temperature control device according to one embodiment of the present invention is provided. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Equipped with, The aforementioned second temperature control system is, A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The first temperature control system is, An air intake port for obtaining air from outside the vehicle, An air heater for heating the air supplied to the first temperature control system, A three-way valve having a first port, a second port, and a third port, and capable of switching the internal flow path connected to the first port, the second port, and the third port, A first duct that connects the first port of the three-way valve to the intake port, A second duct connecting the second port of the three-way valve and the air heater, A third duct that connects the third port of the three-way valve to the low-voltage battery, It has, The three-way valve is configured to switch between a first state in which the first port and the third port are in communication, and a second state in which the second port and the third port are in communication. [Effects of the Invention]

[0008] According to the present invention, it is possible to appropriately regulate the temperature of both the low-voltage battery and the high-voltage battery. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram showing the configuration of the battery temperature control device according to this embodiment. [Figure 2] Figure 2 is a diagram illustrating the state of a three-way valve. [Figure 3] Figure 3 is a flowchart illustrating the control flow of the temperature control unit. [Figure 4] Figure 4 is a flowchart illustrating the control flow of the temperature control unit. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described in detail below with reference to the attached drawings. The specific dimensions, materials, numerical values, etc., shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0011] Figure 1 is a schematic diagram showing the configuration of the battery temperature control device 1 according to this embodiment. Hereafter, the adjustment of the battery temperature may be referred to as temperature control. The battery temperature control device 1 is applied to a vehicle 2. The vehicle 2 is, for example, an electric vehicle or a hybrid electric vehicle.

[0012] The battery temperature control system 1 comprises a low-voltage battery 10, a high-voltage battery 12, a first temperature control system 14, a second temperature control system 16, and a control device 18. The battery temperature control system 1 is applied to a vehicle 2 equipped with both a low-voltage battery 10 and a high-voltage battery 12.

[0013] The low-voltage battery 10 is a rechargeable secondary battery, such as a lithium-ion battery. By using a lithium-ion battery for the low-voltage battery 10, the use of lead can be avoided compared to a configuration in which the low-voltage battery 10 is a lead-acid battery, thereby realizing an environmentally friendly vehicle 2.

[0014] The voltage of the low-voltage battery 10 is, for example, 12V or 24V, which is lower than the voltage of the high-voltage battery 12 described later. The low-voltage battery 10 supplies power to various devices connected to the low-voltage system in the vehicle 2, such as vehicle dynamic control (VDC) and electric power steering (EPS). Note that the devices to which the low-voltage battery 10 supplies power are not limited to the exemplified devices, but may be any devices connected to the low-voltage system.

[0015] The high-voltage battery 12 is a rechargeable secondary battery, such as a lithium-ion battery. The voltage of the high-voltage battery 12 is a predetermined voltage of, for example, 100V or higher, which is higher than the voltage of the low-voltage battery 10. The high-voltage battery 12 supplies power to various devices connected to the high-voltage system in the vehicle 2, such as the motor which is the drive source for the vehicle 2. Note that the devices to which the high-voltage battery 12 supplies power are not limited to the exemplified devices, but may be any devices connected to the high-voltage system. Furthermore, the high-voltage battery 12 may also be capable of supplying power to the low-voltage system through a DC-DC converter.

[0016] In the battery temperature control device 1 of this embodiment, the low-voltage battery 10 and the high-voltage battery 12 are composed of the same type of battery. For example, both the low-voltage battery 10 and the high-voltage battery 12 are lithium-ion batteries.

[0017] Here, the low-voltage battery 10 and the high-voltage battery 12 each have a predetermined optimal temperature range, which is the temperature range within which charging and discharging operations can be performed properly. Although charging and discharging are possible even if the battery temperature is outside the optimal temperature range, there is a risk that a sufficient amount of charging and discharging may not be possible if the battery temperature is outside the optimal temperature range. This optimal temperature range differs depending on the type of battery. Lithium-ion batteries have a narrower optimal temperature range compared to lead-acid batteries. For batteries with a narrow optimal temperature range, it is necessary to actively adjust the battery temperature so that the battery temperature remains within the optimal temperature range. Therefore, the battery temperature control device 1 adjusts the temperature of the low-voltage battery 10 and the temperature of the high-voltage battery 12.

[0018] Furthermore, if the low-voltage battery 10 and the high-voltage battery 12 are composed of the same type of battery, the appropriate temperature range for the low-voltage battery 10 and the appropriate temperature range for the high-voltage battery 12 may be substantially the same or close to each other. In such cases, it is possible to configure the low-voltage battery 10 and the high-voltage battery 12 to be temperature-controlled by the same temperature control system.

[0019] Here, for example, situations may arise where the low-voltage battery 10 consumes relatively high power due to frequent operation of the VDC or EPS, while the high-voltage battery 12 consumes relatively low power due to low output of the drive motor. In this case, the high-voltage battery 12 will consume less power and its temperature will remain within the appropriate temperature range, but the low-voltage battery 10 will consume more power and its temperature may fall outside the appropriate temperature range. Thus, the temperatures of the low-voltage battery 10 and the high-voltage battery 12 change independently of each other.

[0020] Considering these factors, while it is possible to configure the low-voltage battery 10 and the high-voltage battery 12 to be temperature-controlled by the same temperature control system, it is more preferable to independently adjust the temperature of the low-voltage battery 10 and the high-voltage battery 12.

[0021] Therefore, the battery temperature control device 1 of this embodiment includes two temperature control systems: a first temperature control system 14 and a second temperature control system 16. The first temperature control system 14 controls the temperature using air supplied from outside the vehicle 2. The second temperature control system 16 controls the temperature using a heat transfer medium circulating inside the vehicle 2. The first temperature control system 14 is used to control the temperature of the low-voltage battery 10. The second temperature control system 16 is used to control the temperature of the high-voltage battery 12, but it is also configured to be used to control the temperature of the low-voltage battery 10. In other words, the battery temperature control device 1 is configured to control the temperature of the low-voltage battery 10 using either the first temperature control system 14 or the second temperature control system 16.

[0022] As a result, for example, when the temperature of the low-voltage battery 10 can be controlled within the temperature control capacity of the first temperature control system 14, the temperature of the low-voltage battery 10 may be controlled by the first temperature control system 14. On the other hand, when temperature control of the low-voltage battery 10 is required beyond the temperature control capacity of the first temperature control system 14, the temperature of the low-voltage battery 10 may be controlled by the second temperature control system 16. In this way, the temperature control system may be switched according to the temperature control capacity of the first temperature control system 14 and the temperature of the low-voltage battery 10. This makes it possible to appropriately control the temperature of the low-voltage battery 10. The temperature control capacity of the first temperature control system 14 changes according to the temperature of the air supplied to the first temperature control system 14 and the temperature of the air supplied to and heated by the first temperature control system 14.

[0023] Furthermore, for example, while the low-voltage battery 10 is being controlled by the first temperature control system 14, the second temperature control system 16 may be deactivated. In this case, while the low-voltage battery 10 is being controlled by the first temperature control system 14, the low-voltage battery 10 is controlled only by the first temperature control system 14, and the high-voltage battery 12 is controlled only by the second temperature control system 16. In other words, the temperature of the low-voltage battery 10 and the temperature of the high-voltage battery 12 can be controlled independently. This allows the temperature of the low-voltage battery 10 to be appropriately controlled regardless of the temperature of the high-voltage battery 12, and the temperature of the high-voltage battery 12 to be appropriately controlled regardless of the temperature of the low-voltage battery 10.

[0024] As described above, the battery temperature control device 1 of this embodiment can appropriately adjust the temperature of the low-voltage battery 10 and the high-voltage battery 12. The details of the battery temperature control device 1 will be described below.

[0025] The first temperature control system 14 is configured to regulate the temperature of the low-voltage battery 10 using air supplied from outside the vehicle 2. The first temperature control system 14 includes a three-way valve 20, a first duct 22, a second duct 24, a third duct 26, an air intake 28, and an air heater 30.

[0026] The three-way valve 20 has a total of three ports: a first port 32, a second port 34, and a third port 36. An internal flow path 38 is formed inside the three-way valve 20. The three-way valve 20 is configured to allow switching of the internal flow path 38 connected to the first port 32, the second port 34, and the third port 36. The three-way valve 20 will be described in detail later.

[0027] The first duct 22 is formed in a tubular shape. Of the two ends of the first duct 22, the first end is connected to the first port 32 of the three-way valve 20. An air intake port 28 is formed at the second end of the two ends of the first duct 22. The first duct 22 connects the first port 32 of the three-way valve 20 to the air intake port 28. The air intake port 28 can take in air from outside the vehicle 2. In other words, air from outside the vehicle 2 is supplied into the first duct 22 through the air intake port 28. Hereafter, for the sake of explanation, the air taken in through the air intake port 28 may be referred to as intake air.

[0028] The second duct 24 is formed in a tubular shape. Of the two ends of the second duct 24, the first end is connected to the second port 34 of the three-way valve 20. Of the two ends of the second duct 24, the second end is connected to the air heater 30. The second duct 24 connects the second port 34 of the three-way valve 20 to the air heater 30.

[0029] The air heater 30 is, for example, a heat exchanger such as a radiator. The air heater 30 can heat the air supplied to the first temperature control system 14. The air heater 30 is connected to a heat source 40. The heat source 40 is, for example, a motor, but it may be any device that generates heat. The air heater 30 heats the air supplied to the first temperature control system 14 by exchanging heat between the heat generated in the heat source 40 and the air supplied to the first temperature control system 14, and supplies the heated air into the second duct 24. Hereafter, for the sake of explanation, the air supplied to the first temperature control system 14 that has been heated by the air heater 30 may be referred to as heated air. Also, the air supplied to the first temperature control system 14 that has not been heated by the air heater 30, that is, the air sent to the first port 32 of the three-way valve 20 through the intake port 28 and the first duct 22, may be referred to as unheated air.

[0030] Note that the air heater 30 is not limited to a radiator, but may be any device capable of heating air, such as a heater. Also, if the air heater 30 functions as a heat source 40, the heat source 40 may be omitted.

[0031] The third duct 26 is formed in a tubular shape. Of the two ends of the third duct 26, the first end is connected to the third port 36 of the three-way valve 20. Of the two ends of the third duct 26, the second end is connected to the wall of the battery pack in which the low-voltage battery 10 is housed. The second end of the third duct 26 opens into the battery pack of the low-voltage battery 10. The third duct 26 connects the third port 36 of the three-way valve 20 to the low-voltage battery 10.

[0032] Figure 2 illustrates the state of the three-way valve 20. As shown in Figure 2, the three-way valve 20 can be in one of four states: the first state, the second state, the third state, and the fourth state. The three-way valve 20 can switch from any one of the first, second, third, and fourth states to any one of the other states.

[0033] The internal passage 38 of the three-way valve 20 is formed in a T-shaped tubular form. This internal passage 38 is rotatably housed inside the three-way valve 20. The three-way valve 20 can take on a state corresponding to the orientation of the internal passage 38. By rotating the internal passage 38 inside the three-way valve 20, the three-way valve 20 can switch states.

[0034] The first state is one in which the first port 32 and the third port 36 are in communication, and the second port 34 is not in communication with the first port 32 and the third port 36. As shown by the dashed arrow A10 in Figure 2, in the first state, a cooling channel is formed in which the first port 32 and the third port 36 are in communication.

[0035] When the three-way valve 20 is in the first state, outside air from the vehicle 2, obtained through the intake port 28, is sent to the low-voltage battery 10 through the first duct 22, the three-way valve 20, and the third duct 26. In this case, the first temperature control system 14 can cool the low-voltage battery 10 with unheated air flowing through the cooling channel.

[0036] The second state is one in which the second port 34 and the third port 36 are in communication, and the first port 32 is not in communication with the second port 34 and the third port 36. As shown by the dashed arrow A20 in Figure 2, in the second state, a heating channel is formed in which the second port 34 and the third port 36 are in communication.

[0037] When the three-way valve 20 is in the second state, air heated by the air heater 30 is sent to the low-voltage battery 10 through the second duct 24, the three-way valve 20, and the third duct 26. In this case, the first temperature control system 14 can heat the low-voltage battery 10 with heated air heated by the air heater 30 and flowing through the heating channel.

[0038] The third state is a state in which the first port 32, the second port 34, and the third port 36 are all in communication. As shown by the dashed arrows A30 and A32 in Figure 2, in the third state, a mixing channel is formed in which the first port 32 and the third port 36 are in communication, and the second port 34 and the third port 36 are also in communication.

[0039] When the three-way valve 20 is in the third state, the unheated air flowing through the first duct 22 and the heated air heated by the air heater 30 and flowing through the second duct are mixed inside the three-way valve 20. Hereafter, for the sake of explanation, the air that is a mixture of unheated air and heated air may be referred to as a mixed gas.

[0040] When the three-way valve 20 is in the third state, the mixture of gases mixed inside the three-way valve 20 is sent to the low-voltage battery 10 through the third duct 26. In this case, the first temperature control system 14 can adjust the temperature of the low-voltage battery 10 using the mixture of gases sent from the three-way valve 20.

[0041] The fourth state is one in which the first port 32 and the second port 34 are in communication, and the third port 36 is not in communication with the first port 32 and the second port 34. As shown by the dashed arrow A40 in Figure 2, in the fourth state, a bypass flow path is formed that connects the first port 32 and the second port 34. Also, in the fourth state, the third port 36 is blocked from the first port 32 and the second port 34, so the cooling flow path, heating flow path, and mixing flow path described above are not formed. In other words, in the fourth state, neither unheated air nor heated air is supplied to the low-voltage battery 10.

[0042] When the three-way valve 20 is in the fourth state, the unheated air flowing through the first duct 22 can flow to the air heater 30 through the three-way valve 20 and the second duct 24. Also, when the three-way valve 20 is in the fourth state, the heated air flowing through the second duct can flow to the outside of the vehicle 2 through the three-way valve 20, the first duct 22 and the air intake 28.

[0043] Thus, the three-way valve 20 is configured to allow switching between any one of the cooling channel, heating channel, mixing channel, and bypass channel described above.

[0044] Furthermore, the three-way valve 20 is not limited to a configuration in which it can take on any of the four states from the first to the fourth state. For example, the three-way valve 20 may be configured to take on any of the two states, the first state and the second state, with the third and fourth states omitted. In other words, the three-way valve 20 may be configured to be switchable between the first and second states, or in other words, to be switchable between the cooling flow path and the heating flow path as described above.

[0045] Furthermore, the first temperature control system 14 was configured such that the air heated by the air heater 30 was obtained separately from the air obtained from the air intake port 28. However, the first temperature control system 14 may also be configured such that a portion of the air obtained from the air intake port 28 is supplied to the air heater 30.

[0046] Returning to Figure 1, the second temperature control system 16 is a different temperature control system from the first temperature control system 14. The second temperature control system 16 is configured to regulate the temperature of the high-voltage battery 12 using a heat transfer medium circulating inside the vehicle 2. The heat transfer medium circulates along the second temperature control system 16, and heat exchange can occur in each element constituting the second temperature control system 16. The heat transfer medium is, for example, water, but any fluid that can be used for heat exchange may be used. Furthermore, as will be described later, the second temperature control system 16 is configured to regulate not only the temperature of the high-voltage battery 12 but also the temperature of the low-voltage battery 10. Also, for example, to prevent the air in the first temperature control system 14 and the heat transfer medium in the second temperature control system 16 from mixing, the air flow path in the first temperature control system 14 and the heat transfer medium flow path in the second temperature control system 16 are independent of each other.

[0047] The second temperature control system 16 includes a first heat exchanger 50. The first heat exchanger 50 is positioned in contact with the high-voltage battery 12. For example, the first heat exchanger 50 is formed in a plate shape through which a heat transfer medium flows, and the high-voltage battery 12 is installed on top of the first heat exchanger 50. The first heat exchanger 50 is configured to allow heat exchange between the high-voltage battery 12 and the heat transfer medium.

[0048] The second temperature control system 16 includes a second heat exchanger 52. The second heat exchanger 52 is positioned in contact with the low-voltage battery 10. For example, the second heat exchanger 52 is formed in a plate shape through which a heat transfer medium flows, and the low-voltage battery 10 is installed on top of the second heat exchanger 52. The second heat exchanger 52 is configured to allow heat exchange between the low-voltage battery 10 and the heat transfer medium.

[0049] The second temperature control system 16 includes a first common pipe 60, a heating pipe 62, a cooling pipe 64, and a second common pipe 66. A heat transfer medium flows through the inside of each of the first common pipe 60, the heating pipe 62, the cooling pipe 64, and the second common pipe 66.

[0050] The second temperature control system 16 includes a first switching valve 70a, a second switching valve 70b, a third switching valve 70c, a fourth switching valve 70d, a fifth switching valve 70e, and a sixth switching valve 70f. The first switching valve 70a, the second switching valve 70b, the third switching valve 70c, the fourth switching valve 70d, the fifth switching valve 70e, and the sixth switching valve 70f are sometimes collectively referred to as switching valves. Each of the switching valves in the second temperature control system 16 is, for example, a three-way valve.

[0051] The first common piping 60 extends from the first switching valve 70a and is connected to the first heat exchanger 50. The first common piping 60 also extends from the first heat exchanger 50 and is connected to the second switching valve 70b. The second temperature control system 16 includes a first pump 72. The first pump 72 is installed between the first switching valve 70a and the first heat exchanger 50 in the first common piping 60. The first pump 72 circulates the heat transfer medium in the first common piping 60 in the direction from the first switching valve toward the first heat exchanger 50.

[0052] The second temperature control system 16 includes a heater 74. The heating pipe 62 extends from the second switching valve 70b and is connected to the first switching valve 70a via the heater 74. The heater 74 is located between the second switching valve 70b and the first switching valve 70a in the heating pipe 62. The heater 74 heats the heat transfer medium flowing through the heating pipe 62. The heater 74 is, for example, a PTC (Positive Temperature Coefficient) heater, but may be any heater capable of heating the heat transfer medium.

[0053] The second temperature control system 16 includes a chiller 76. Cooling piping 64 extends from the second switching valve 70b and is connected to the first switching valve 70a via the chiller 76. The chiller 76 is located between the second switching valve 70b and the first switching valve 70a in the cooling piping 64. The chiller 76 cools the heat transfer medium flowing through the cooling piping 64.

[0054] The first switching valve 70a and the second switching valve 70b can switch between the heating pipe 62 and the cooling pipe 64 that are in communication with the first common pipe 60.

[0055] For example, suppose that the first common pipe 60 and the heating pipe 62 are connected by the first switching valve 70a and the second switching valve 70b, and the cooling pipe 64 is isolated from the first common pipe 60 and the heating pipe 62. In this case, the heat transfer medium circulates through the heating pipe 62 and the first common pipe 60. In other words, the heat transfer medium heated by the heater 74 is supplied to the first heat exchanger 50. As a result, the high-voltage battery 12 can be heated by heat exchange with the heat transfer medium supplied to the first heat exchanger 50.

[0056] On the other hand, the first common pipe 60 and the cooling pipe 64 are connected by the first switching valve 70a and the second switching valve 70b, and the heating pipe 62 is isolated from the first common pipe 60 and the cooling pipe 64. In this case, the heat transfer medium circulates through the cooling pipe 64 and the first common pipe 60. In other words, the heat transfer medium cooled by the chiller 76 is supplied to the first heat exchanger 50. As a result, the high-voltage battery 12 can be cooled by heat exchange with the heat transfer medium supplied to the first heat exchanger 50.

[0057] The third switching valve 70c is provided between the heater 74 and the first switching valve 70a in the heating pipe 62. The fourth switching valve 70d is provided between the second switching valve 70b and the heater 74 in the heating pipe 62.

[0058] The fifth switching valve 70e is provided between the chiller 76 and the first switching valve 70a in the cooling pipe 64. The sixth switching valve 70f is provided between the second switching valve 70b and the chiller 76 in the cooling pipe 64.

[0059] The second common pipe 66 extends from the third switching valve 70c and from the fifth switching valve 70e, and these pipes merge at the junction 80. The second common pipe 66 extends from the junction 80 and is connected to the second heat exchanger 52. The second common pipe 66 also extends from the second heat exchanger 52 and branches into two at the branching section 82. One of the two branches of the second common pipe 66 at the branching section 82 is connected to the fourth switching valve 70d, and the other branch is connected to the sixth switching valve 70f.

[0060] The second temperature control system 16 includes a second pump 84. The second pump 84 is installed between the junction 80 in the second common piping 66 and the second heat exchanger 52. The second pump 84 circulates the heat transfer medium in the second common piping 66 in the direction from the third switching valve 70c or the fifth switching valve 70e toward the second heat exchanger 52.

[0061] The third switching valve 70c and the fourth switching valve 70d can switch the connection between the second common pipe 66 and the heating pipe 62 on and off.

[0062] For example, suppose that the second common piping 66 and the heating piping 62 are connected by the third switching valve 70c and the fourth switching valve 70d. In this case, the heat transfer medium circulates through the heater of the heating piping 62 and the second common piping 66. That is, the heat transfer medium heated by the heater 74 is supplied to the second heat exchanger 52. As a result, the low-voltage battery 10 can be heated by heat exchange with the heat transfer medium supplied to the second heat exchanger 52.

[0063] On the other hand, the second common piping 66 is isolated from the heating piping 62 by the third switching valve 70c and the fourth switching valve 70d. In this case, since the heat transfer medium heated by the heater 74 is not supplied to the second common piping 66, the low-voltage battery 10 is not heated by the second temperature control system 16.

[0064] Furthermore, when the second common pipe 66 is connected to the heating pipe 62, the heat transfer medium heated by the heater 74 may be supplied to the second heat exchanger 52 through the second common pipe 66, and also to the first heat exchanger 50 through the first common pipe 60. Alternatively, when the second common pipe 66 is connected to the heating pipe 62, the heat transfer medium heated by the heater 74 may not be supplied to the first common pipe 60 or the first heat exchanger 50, but only to the second heat exchanger 52 through the second common pipe 66.

[0065] The fifth switching valve 70e and the sixth switching valve 70f can switch the connection between the second common pipe 66 and the cooling pipe 64 on and off.

[0066] For example, suppose the second common piping 66 and the cooling piping 64 are connected by the fifth switching valve 70e and the sixth switching valve 70f. In this case, the heat transfer medium circulates through the chiller 76 of the cooling piping 64 and the second common piping 66. In other words, the heat transfer medium cooled by the chiller 76 is supplied to the second heat exchanger 52. As a result, the low-voltage battery 10 can be cooled by heat exchange with the heat transfer medium supplied to the second heat exchanger 52.

[0067] On the other hand, the second common piping 66 is isolated from the cooling piping 64 by the fifth switching valve 70e and the sixth switching valve 70f. In this case, since the heat transfer medium cooled by the chiller 76 is not supplied to the second common piping 66, the low-voltage battery 10 is not cooled by the second temperature control system 16.

[0068] Furthermore, when the second common pipe 66 is connected to the cooling pipe 64, the heat transfer medium cooled by the chiller 76 may be supplied to the second heat exchanger 52 through the second common pipe 66, and also to the first heat exchanger 50 through the first common pipe 60. Alternatively, when the second common pipe 66 is connected to the cooling pipe 64, the heat transfer medium heated by the chiller 76 may not be supplied to the first common pipe 60 or the first heat exchanger 50, but only to the second heat exchanger 52 through the second common pipe 66.

[0069] The second temperature control system 16 includes a sub-cooling pipe 90, a compressor 92, a condenser 94, and an expansion valve 96. The sub-cooling pipe 90 extends from the chiller 76 and is configured to return to the chiller 76 after passing through the compressor 92, condenser 94, and expansion valve 96 in that order. The sub-cooling pipe 90 forms a separate flow path from the cooling pipe 64. Inside the sub-cooling pipe 90, a sub-heat transfer medium flows separately from the heat transfer medium inside the cooling pipe 64. The sub-heat transfer medium may be, for example, water, but may be any fluid that can be used for heat exchange.

[0070] The compressor 92 compresses the sub-heat transfer medium supplied from the chiller 76 through the sub-cooling pipe 90 and sends it to the condenser 94. The condenser 94 exchanges heat between the air outside the vehicle 2 and the sub-heat transfer medium compressed by the compressor 92, releasing the heat from the sub-heat transfer medium to the outside of the vehicle 2. The sub-heat transfer medium inside the condenser 94 undergoes a phase transition from gas phase to liquid phase because it is cooled under high pressure. The sub-heat transfer medium after heat exchange in the condenser 94 is sent to the expansion valve 96.

[0071] The expansion valve 96 sprays the sub-heat transfer medium supplied from the condenser 94 into the chiller 76. The sprayed sub-heat transfer medium undergoes a rapid pressure drop and a phase transition to the gas phase. The temperature of the sub-heat transfer medium decreases due to this vaporization. The chiller 76 exchanges heat between the sub-heat transfer medium, whose temperature has decreased in the sub-cooling pipe 90, and the heat transfer medium in the cooling pipe 64, thereby cooling the heat transfer medium in the cooling pipe 64.

[0072] The battery temperature control device 1 includes a first battery temperature sensor 100, a second battery temperature sensor 102, an intake air temperature sensor 104, and a heated air temperature sensor 106.

[0073] The first battery temperature sensor 100 detects the temperature of the high-voltage battery 12. The second battery temperature sensor 102 detects the temperature of the low-voltage battery 10. The intake air temperature sensor 104 is installed in the first duct 22. The intake air temperature sensor 104 detects the temperature of the air flowing through the first duct 22, which is acquired through the intake port 28, i.e., the temperature of the unheated air. The heated air temperature sensor 106 is installed in the second duct 24. The heated air temperature sensor 106 detects the temperature of the air that is heated by the air heater 30 and flows through the second duct 24, i.e., the temperature of the heated air.

[0074] The control device 18 includes one or more processors 110 and one or more memories 112 connected to the processors 110. The memories 112 include ROM, which stores programs, etc., and RAM as a work area. The processors 110 of the control device 18 cooperate with the programs contained in the memories 112 to control the entire vehicle 2. The processors 110 also function as a temperature control unit 120 by executing programs.

[0075] The temperature control unit 120 acquires the temperature of the high-voltage battery 12 detected by the first battery temperature sensor 100. Based on the temperature of the high-voltage battery 12, the temperature control unit 120 adjusts the temperature of the high-voltage battery 12.

[0076] If the temperature of the high-voltage battery 12 is higher than the upper limit temperature of the appropriate temperature range for the high-voltage battery 12, the temperature control unit 120 cools the high-voltage battery 12 using a heat transfer medium cooled by the chiller 76 in the second temperature control system 16. More specifically, the temperature control unit 120 controls the first switching valve 70a and the second switching valve 70b so that the first common piping 60 and the cooling piping 64 are in communication, and the heating piping 62 is isolated from the first common piping 60 and the cooling piping 64. By connecting the first common piping 60 and the cooling piping 64, the heat transfer medium cooled by the chiller 76 is supplied to the first heat exchanger 50 through the cooling piping 64 and the first common piping 60. As a result, the high-voltage battery 12 is cooled, and the temperature of the high-voltage battery 12 can be returned to the appropriate temperature range.

[0077] If the temperature of the high-voltage battery 12 is lower than the lower limit temperature of the appropriate temperature range for the high-voltage battery 12, the temperature control unit 120 heats the high-voltage battery 12 using a heat transfer medium heated by the heater 74 in the second temperature control system 16. More specifically, the temperature control unit 120 controls the first switching valve 70a and the second switching valve 70b so that the first common pipe 60 and the heating pipe 62 are in communication, and the cooling pipe 64 is isolated from the first common pipe 60 and the heating pipe 62. By connecting the first common pipe 60 and the heating pipe 62, the heat transfer medium heated by the heater 74 is supplied to the first heat exchanger 50 through the heating pipe 62 and the first common pipe 60. As a result, the high-voltage battery 12 is heated, and the temperature of the high-voltage battery 12 can be returned to the appropriate temperature range.

[0078] The temperature control unit 120 can switch the state of the first switching valve 70a and the second switching valve 70b by controlling predetermined actuators that drive the first switching valve 70a and the second switching valve 70b.

[0079] The temperature control unit 120 acquires the temperature of the low-voltage battery 10 detected by the second battery temperature sensor 102. Based on the temperature of the low-voltage battery 10, the temperature control unit 120 adjusts the temperature of the low-voltage battery 10.

[0080] If the temperature of the low-voltage battery 10 is higher than the upper limit temperature of the appropriate temperature range for the low-voltage battery 10, the temperature control unit 120 compares the temperature of the air supplied to the first temperature control system 14, i.e., the temperature of the unheated air, with the temperature of the low-voltage battery 10.

[0081] If the temperature of the air supplied to the first temperature control system 14 is lower than the temperature of the low-voltage battery 10, the air supplied to the first temperature control system 14 can effectively cool the low-voltage battery 10. Therefore, if the temperature of the air supplied to the first temperature control system 14 is lower than the temperature of the low-voltage battery 10, the temperature control unit 120 will perform cooling of the low-voltage battery 10 using the first temperature control system 14. More specifically, the temperature control unit 120 sets the three-way valve 20 of the first temperature control system 14 to a first state. In the first state, the first duct 22 and the third duct 26 are in communication, so unheated air is supplied to the low-voltage battery 10. As a result, the low-voltage battery 10 is cooled, and the temperature of the low-voltage battery 10 can be returned to an appropriate temperature range.

[0082] Furthermore, the temperature control unit 120 can switch the state of the three-way valve 20 of the first temperature control system 14 by controlling a predetermined actuator that drives the three-way valve 20.

[0083] If the temperature of the air supplied to the first temperature control system 14 is higher than or equal to the temperature of the low-voltage battery 10, the air supplied to the first temperature control system 14 cannot sufficiently cool the low-voltage battery 10. In such cases, the second temperature control system 16 is used to cool the low-voltage battery 10. That is, the temperature control unit 120 cools the low-voltage battery 10 using the second temperature control system 16 if the temperature of the air supplied to the first temperature control system 14 is higher than or equal to the temperature of the low-voltage battery 10. More specifically, the temperature control unit 120 sets the fifth switching valve 70e and the sixth switching valve 70f to a state where the second common piping 66 and the cooling piping 64 are in communication. At the same time, the temperature control unit 120 sets the third switching valve 70c and the fourth switching valve 70d to a state where the second common piping 66 is isolated from the heating piping 62. The second common pipe 66 and the cooling pipe 64 are connected, allowing the heat transfer medium cooled by the chiller 76 to be supplied to the second heat exchanger 52 through the cooling pipe 64 and the second common pipe 66. This cools the low-voltage battery 10, bringing its temperature back within the appropriate range.

[0084] Furthermore, the temperature control unit 120 can switch the state of the fifth switching valve 70e and the sixth switching valve 70f by controlling predetermined actuators that drive the fifth switching valve 70e and the sixth switching valve 70f. The temperature control unit 120 can also switch the state of the third switching valve 70c and the fourth switching valve 70d by controlling predetermined actuators that drive the third switching valve 70c and the fourth switching valve 70d.

[0085] However, if the low-voltage battery 10 generates a relatively large amount of heat, even if the first temperature control system 14 cools the low-voltage battery 10 for a long period of time, it may not be possible for the temperature of the low-voltage battery 10 to return to the appropriate temperature range.

[0086] Therefore, the temperature control unit 120 may, after a predetermined time has elapsed since the start of cooling of the low-voltage battery 10 by the first temperature control system 14, stop cooling of the low-voltage battery 10 by the first temperature control system 14 and switch to cooling of the low-voltage battery 10 by the second temperature control system 16. Cooling with a heat transfer medium usually has a higher cooling capacity than cooling with unheated air. For this reason, the system may switch from cooling by the first temperature control system 14 to cooling by the second temperature control system 16, which has a higher cooling capacity than the first temperature control system 14.

[0087] For example, the temperature control unit 120 sets the three-way valve 20 of the first temperature control system 14 to the fourth state. The temperature control unit 120 sets the fifth switching valve 70e and the sixth switching valve 70f to a state where the second common pipe 66 and the cooling pipe 64 are in communication. At the same time, the temperature control unit 120 sets the third switching valve 70c and the fourth switching valve 70d to a state where the second common pipe 66 is isolated from the heating pipe 62. As a result, the low-voltage battery 10 is cooled further, and even if the heat generated by the low-voltage battery 10 is relatively large, the temperature of the low-voltage battery 10 can be returned to the appropriate temperature range.

[0088] In this case, the cooling of the low-voltage battery 10 by the first temperature control system 14 was discontinued, and the system switched from cooling by the first temperature control system 14 to cooling by the second temperature control system 16. However, the temperature control unit 120 may continue cooling the low-voltage battery 10 by the first temperature control system 14 while simultaneously performing cooling of the low-voltage battery 10 by the second temperature control system 16.

[0089] If the temperature of the low-voltage battery 10 is lower than the lower limit temperature of the appropriate temperature range for the low-voltage battery 10, the temperature control unit 120 compares the temperature of the air heated by the air heater 30, i.e., the temperature of the heated air, with the temperature of the low-voltage battery 10.

[0090] If the temperature of the air heated by the air heater 30 is higher than the temperature of the low-voltage battery 10, the air heated by the air heater 30 can effectively heat the low-voltage battery 10. Therefore, if the temperature of the air heated by the air heater 30 is higher than the temperature of the low-voltage battery 10, the temperature control unit 120 will heat the low-voltage battery 10 using the first temperature control system 14. More specifically, the temperature control unit 120 will set the three-way valve 20 of the first temperature control system 14 to the second state. In the second state, the second duct 24 and the third duct 26 are connected, so heated air is supplied to the low-voltage battery 10. As a result, the low-voltage battery 10 is heated, and its temperature can be returned to the appropriate temperature range.

[0091] If the temperature of the air heated by the air heater 30 is below the temperature of the low-voltage battery 10, the air heated by the air heater 30 cannot sufficiently heat the low-voltage battery 10. In such cases, the second temperature control system 16 is used to heat the low-voltage battery 10. Specifically, the temperature control unit 120 heats the low-voltage battery 10 using the second temperature control system 16 if the temperature of the air heated by the air heater 30 is below the temperature of the low-voltage battery 10. More specifically, the temperature control unit 120 sets the third switching valve 70c and the fourth switching valve 70d to a state where the second common pipe 66 and the heating pipe 62 are in communication. At the same time, the temperature control unit 120 sets the fifth switching valve 70e and the sixth switching valve 70f to a state where the second common pipe 66 is isolated from the cooling pipe 64. The second common pipe 66 and the heating pipe 62 are connected, allowing the heat transfer medium heated by the heater 74 to be supplied to the second heat exchanger 52 through the heating pipe 62 and the second common pipe 66. This heats the low-voltage battery 10, bringing its temperature back to an appropriate range.

[0092] Incidentally, in environments where the low-voltage battery 10 is cooled, such as when the outside temperature of vehicle 2 is below freezing, even if the first temperature control system 14 heats the low-voltage battery 10 for a long period of time, the temperature of the low-voltage battery 10 may not return to the appropriate temperature range.

[0093] Therefore, the temperature control unit 120 may, after a predetermined time has elapsed since the start of heating of the low-voltage battery 10 by the first temperature control system 14, stop heating of the low-voltage battery 10 by the first temperature control system 14 and switch to heating of the low-voltage battery 10 by the second temperature control system 16. Heating with a heat transfer medium usually has a higher heating capacity than heating with heated air. For this reason, the system may switch from heating by the first temperature control system 14 to heating by the second temperature control system 16, which has a higher heating capacity than the first temperature control system 14.

[0094] For example, the temperature control unit 120 sets the three-way valve 20 of the first temperature control system 14 to the fourth state. The temperature control unit 120 sets the third switching valve 70c and the fourth switching valve 70d to a state where the second common pipe 66 and the heating pipe 62 are in communication. At the same time, the temperature control unit 120 sets the fifth switching valve 70e and the sixth switching valve 70f to a state where the second common pipe 66 is isolated from the cooling pipe 64. As a result, even in an environment where the low-voltage battery 10 is heated more and cooled more, the temperature of the low-voltage battery 10 can be returned to the appropriate temperature range.

[0095] In this case, heating of the low-voltage battery 10 by the first temperature control system 14 was stopped, and the heating was switched from the first temperature control system 14 to the second temperature control system 16. However, the temperature control unit 120 may continue heating of the low-voltage battery 10 by the first temperature control system 14 while simultaneously performing heating of the low-voltage battery 10 by the second temperature control system 16.

[0096] The temperature control unit 120 derives the temperature of the mixture of heated air and unheated air if the temperature of the low-voltage battery 10 is within the appropriate temperature range. For example, the temperature control unit 120 derives the average value of the temperature detected by the intake air temperature sensor 104 and the temperature detected by the heated air temperature sensor 106 as the temperature of the mixture. The temperature control unit 120 then determines whether the derived temperature of the mixture is within the appropriate temperature range of the low-voltage battery 10.

[0097] The temperature control unit 120 supplies the fuel mixture to the low-voltage battery 10 if the temperature of the fuel mixture is within the appropriate temperature range for the low-voltage battery 10, thereby maintaining the temperature of the low-voltage battery 10 within the appropriate temperature range. This prevents the temperature of the low-voltage battery 10 from falling outside the appropriate temperature range.

[0098] Figures 3 and 4 are flowcharts illustrating the control flow of the temperature control unit 120. Point "A" in Figure 3 is connected to point "A" in Figure 4. Figures 3 and 4 describe the temperature control of the low-voltage battery 10, while the temperature control of the high-voltage battery 12 is not described.

[0099] In Figures 3 and 4, "TL" is the temperature detected by the first battery temperature sensor 100 and indicates the temperature of the low-voltage battery 10. "TBa" indicates the lower limit temperature of the appropriate temperature range for the low-voltage battery 10. "TBb" indicates the upper limit temperature of the appropriate temperature range for the low-voltage battery 10. "Ta" is the temperature detected by the intake air temperature sensor 104 and indicates the temperature of the unheated air supplied to the first temperature control system 14, i.e., the non-heated air. "TRd" is the temperature detected by the heated air temperature sensor 106 and indicates the temperature of the air heated by the air heater 30, i.e., the heated air supplied to the first temperature control system 14. "Tmix" indicates the temperature of the mixture.

[0100] The temperature control unit 120 repeatedly executes the processes shown in Figures 3 and 4 each time a predetermined interrupt timing occurs, which takes place at predetermined intervals. As shown in Figure 3, when the predetermined interrupt timing arrives, the temperature control unit 120 acquires the temperature of the low-voltage battery 10 "TL", the temperature of the unheated air "Ta", and the temperature of the heated air "TRd" (S10).

[0101] If the three-way valve 20 of the first temperature control system 14 has not elapsed a predetermined time in the first state (NO in S11) and has not elapsed a predetermined time in the second state (NO in S12), the temperature control unit 120 proceeds to the process in step S13.

[0102] In step S13, if the low-voltage battery is not currently being controlled by the second temperature control system 16 (NO in S13), the temperature control unit 120 proceeds from "A" in Figure 3 to "A" in Figure 4, and then proceeds to the process in step S20 in Figure 4.

[0103] In step S20, the temperature control unit 120 determines whether the temperature "TL" of the low-voltage battery 10 is higher than the upper limit temperature "TBb" of the appropriate temperature range (S20).

[0104] If the temperature "TL" of the low-voltage battery 10 is higher than the upper limit temperature "TBb" of the appropriate temperature range (YES in S20), the temperature control unit 120 determines whether the temperature "Ta" of the unheated air is lower than the temperature "TL" of the low-voltage battery 10 (S21).

[0105] If the temperature of the unheated air "Ta" is lower than the temperature of the low-voltage battery 10 "TL" (YES in S21), the temperature control unit 120 sets the state of the three-way valve 20 of the first temperature control system 14 to the first state in which unheated air is sent to the low-voltage battery 10 through the three-way valve 20 (S22), and terminates the series of processes. If the state of the three-way valve 20 is already the first state, the first state is maintained. As a result, the low-voltage battery 10 is cooled by the first temperature control system 14.

[0106] If the temperature of the unheated air "Ta" is equal to or greater than the temperature of the low-voltage battery 10 "TL" (NO in S21), the temperature control unit 120 sets the state of the three-way valve 20 of the first temperature control system 14 to the fourth state, in which the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S23). If the state of the three-way valve 20 is already the fourth state, the fourth state is maintained. The temperature control unit 120 then performs cooling of the low-voltage battery 10 by the second temperature control system 16 (S24), and the series of processes ends. If cooling of the low-voltage battery 10 by the second temperature control system 16 is already being performed, the cooling of the low-voltage battery 10 by the second temperature control system 16 is continued.

[0107] In step S20, if the temperature "TL" of the low-voltage battery 10 is less than or equal to the upper limit temperature "TBb" of the appropriate temperature range (NO in S20), the temperature control unit 120 determines whether the temperature "TL" of the low-voltage battery 10 is lower than the lower limit temperature "TBa" of the appropriate temperature range (S30).

[0108] If the temperature "TL" of the low-voltage battery 10 is lower than the lower limit temperature "TBa" of the appropriate temperature range (YES in S30), the temperature control unit 120 determines whether the temperature "TRd" of the heated air is higher than the temperature "TL" of the low-voltage battery 10 (S31).

[0109] If the temperature of the heated air "TRd" is higher than the temperature of the low-voltage battery 10 "TL" (YES in S31), the temperature control unit 120 sets the state of the three-way valve 20 of the first temperature control system 14 to the second state in which heated air is sent to the low-voltage battery 10 through the three-way valve 20 (S32), and terminates the series of processes. If the state of the three-way valve 20 is already the second state, the second state is maintained. As a result, the low-voltage battery 10 is heated by the first temperature control system 14.

[0110] If the heated air temperature "TRd" is less than or equal to the low-voltage battery temperature "TL" (NO in S31), the temperature control unit 120 sets the state of the three-way valve 20 of the first temperature control system 14 to the fourth state, in which the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S33). If the state of the three-way valve 20 is already the fourth state, the fourth state is maintained. The temperature control unit 120 then executes heating of the low-voltage battery 10 by the second temperature control system 16 (S34), and the series of processes ends. If heating of the low-voltage battery 10 by the second temperature control system 16 is already being performed, heating of the low-voltage battery 10 by the second temperature control system 16 is continued.

[0111] If the temperature "TL" of the low-voltage battery 10 is below the upper limit temperature "TBb" of the appropriate temperature range (NO in S20), and the temperature "TL" of the low-voltage battery 10 is above the lower limit temperature "TBa" of the appropriate temperature range (NO in S30), then the temperature "TL" of the low-voltage battery 10 is within the appropriate temperature range. In this case, the temperature control unit 120 derives the temperature of the mixture "Tmix" (S40).

[0112] The temperature control unit 120 determines whether the derived temperature of the mixture "Tmix" is above the lower limit temperature "TBa" of the appropriate temperature range for the low-voltage battery 10 and below the upper limit temperature "TBb", that is, whether it is within the appropriate temperature range for the low-voltage battery 10 (S41).

[0113] If the temperature of the air-fuel mixture "Tmix" is determined to be within the appropriate temperature range of the low-voltage battery 10 (YES in S41), the temperature control unit 120 sets the state of the three-way valve 20 of the first temperature control system 14 to the third state in which the air-fuel mixture is supplied to the low-voltage battery 10 (S42), and terminates the series of processes. If the state of the three-way valve 20 is already the third state, the third state is maintained. As a result, the air-fuel mixture is supplied to the low-voltage battery 10, and the temperature of the low-voltage battery 10 is maintained within the appropriate temperature range by the air-fuel mixture.

[0114] If the temperature of the air-fuel mixture "Tmix" is determined to be outside the appropriate temperature range for the low-voltage battery 10 (NO in S41), the temperature control unit 120 sets the state of the three-way valve 20 of the first temperature control system 14 to the fourth state, where the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S43), and terminates the series of processes. If the state of the three-way valve 20 is already the fourth state, the fourth state is maintained. In this case, the temperature of the low-voltage battery 10 is not controlled, but since the low-voltage battery 10 is already within the appropriate temperature range, the low-voltage battery 10 can be charged and discharged appropriately even without temperature control.

[0115] In step S11 of Figure 3, if the three-way valve 20 of the first temperature control system 14 remains in the first state for a predetermined time (YES in S11), the temperature control unit 120 determines whether the temperature "TL" of the low-voltage battery 10 is higher than the upper limit temperature "TBb" of the appropriate temperature range (S50).

[0116] If the temperature "TL" of the low-voltage battery 10 is higher than the upper limit temperature "TBb" of the appropriate temperature range (YES in S50), the temperature control unit 120 sets the three-way valve 20 of the first temperature control system 14 to a fourth state in which the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S51). Then, the temperature control unit 120 performs cooling by the second temperature control system 16 (S51) and ends the series of processes. In this case, since the temperature "TL" of the low-voltage battery 10 did not return to the appropriate temperature range even after continuing cooling by the first temperature control system 14 for a predetermined time, the system switches from cooling by the first temperature control system 14 to cooling by the second temperature control system 16. This makes it easier for the temperature of the low-voltage battery 10 to return to the appropriate temperature range.

[0117] If the temperature "TL" of the low-voltage battery 10 is below the upper limit temperature "TBb" of the appropriate temperature range (NO in S50), the temperature control unit 120 sets the three-way valve of the first temperature control system to the fourth state in which the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S53), and terminates the series of processes. In this case, the cooling of the low-voltage battery 10 by the first temperature control system 14 has continued for a predetermined time, and the temperature of the low-voltage battery 10 has returned to the appropriate temperature range, so the cooling of the low-voltage battery 10 by the first temperature control system 14 is stopped.

[0118] In step S12, if the three-way valve 20 of the first temperature control system 14 remains in the second state for a predetermined time (YES in S12), the temperature control unit 120 determines whether the temperature "TL" of the low-voltage battery 10 is lower than the lower limit temperature "TBa" of the appropriate temperature range (S60).

[0119] If the temperature "TL" of the low-voltage battery 10 is lower than the lower limit temperature "TBa" of the appropriate temperature range (YES in S60), the temperature control unit 120 sets the three-way valve 20 of the first temperature control system 14 to a fourth state in which the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S61). Then, the temperature control unit 120 performs heating by the second temperature control system 16 (S62) and ends the series of processes. In this case, since the temperature "TL" of the low-voltage battery 10 did not return to the predetermined temperature range even after heating by the first temperature control system 14 was continued for a predetermined time, the system switches from heating by the first temperature control system 14 to heating by the second temperature control system 16. This makes it easier for the temperature of the low-voltage battery 10 to return to the appropriate temperature range.

[0120] If the temperature "TL" of the low-voltage battery 10 is above the lower limit temperature "TBa" of the appropriate temperature range (NO in S60), the temperature control unit 120 sets the three-way valve 20 of the first temperature control system 14 to a fourth state in which the flow path between the three-way valve 20 and the low-voltage battery 10 is blocked (S63), and terminates the series of processes. In this case, the heating of the low-voltage battery 10 by the first temperature control system 14 is stopped because the temperature of the low-voltage battery 10 has returned to the appropriate temperature range due to the heating by the first temperature control system 14 continuing for a predetermined time.

[0121] In step S13, if the low-voltage battery 10 is currently being controlled by the second temperature control system 16 (YES in S13), the temperature control unit 120 determines whether the temperature "TL" of the low-voltage battery 10 is above the lower limit temperature "TBa" of the appropriate temperature range and below the upper limit temperature "TBb" of the appropriate temperature range, that is, whether it is within the appropriate temperature range (S70).

[0122] If the temperature "TL" of the low-voltage battery 10 is within the appropriate temperature range (YES in S70), the temperature control unit 120 stops the temperature control of the low-voltage battery 10 by the second temperature control system 16 (S71) and proceeds to the process of step S20 described above.

[0123] If the temperature "TL" of the low-voltage battery 10 is not within the appropriate temperature range (NO in S70), the temperature control unit 120 terminates the series of processes. In this case, temperature control of the low-voltage battery 10 by the second temperature control system 16 continues.

[0124] As described above, the battery temperature control device 1 of this embodiment includes a first temperature control system 14 capable of adjusting the temperature of the low-voltage battery 10 and a second temperature control system 16 capable of adjusting the temperature of the high-voltage battery 12. The second temperature control system 16 has not only a first heat exchanger 50 capable of heat exchange with the high-voltage battery 12, but also a second heat exchanger 52 capable of heat exchange with the low-voltage battery 10. The battery temperature control device 1 of this embodiment is configured to adjust the temperature of the low-voltage battery 10 by the heat transfer medium supplied to the second heat exchanger 52 of the second temperature control system 16.

[0125] Because of this configuration, the battery temperature control device 1 of this embodiment can switch between the first temperature control system 14 and the second temperature control system 16 depending on the temperature control capacity of the first temperature control system 14 and the heat generation state of the low-voltage battery 10. As a result, the battery temperature control device 1 of this embodiment can appropriately adjust the temperature of the low-voltage battery 10.

[0126] Furthermore, the battery temperature control device 1 of this embodiment can control the temperature of the low-voltage battery 10 using the first temperature control system 14 and the temperature of the high-voltage battery 12 using the second temperature control system 16. As a result, the battery temperature control device 1 of this embodiment can independently adjust the temperature of the low-voltage battery 10 and the high-voltage battery 12.

[0127] Therefore, according to the battery temperature control device 1 of this embodiment, the temperature of the low-voltage battery 10 and the temperature of the high-voltage battery 12 can be appropriately adjusted.

[0128] Furthermore, in this embodiment, the temperature control unit 120 of the battery temperature control device 1 performs cooling of the low-voltage battery 10 by the first temperature control system 14 if the temperature of the unheated air is lower than the temperature of the low-voltage battery 10. If the temperature of the unheated air is equal to or higher than the temperature of the low-voltage battery 10, the temperature control unit 120 performs cooling of the low-voltage battery 10 by the second temperature control system 16. As a result, the battery temperature control device 1 of this embodiment can reliably cool the low-voltage battery 10 regardless of the temperature of the unheated air.

[0129] Furthermore, in this embodiment, the temperature control unit 120 of the battery temperature control device 1 heats the low-voltage battery 10 using the first temperature control system 14 if the temperature of the heated air is higher than the temperature of the low-voltage battery 10. If the temperature of the heated air is lower than or equal to the temperature of the low-voltage battery 10, the temperature control unit 120 heats the low-voltage battery 10 using the second temperature control system 16. As a result, the battery temperature control device 1 of this embodiment can reliably heat the low-voltage battery 10 regardless of the temperature of the heated air.

[0130] Furthermore, the temperature control unit 120 of the battery temperature control device 1 in this embodiment supplies the fuel mixture to the low-voltage battery 10 if the temperature of the fuel mixture is within the appropriate temperature range for the low-voltage battery 10, thereby maintaining the temperature of the low-voltage battery 10 within the appropriate temperature range. As a result, the battery temperature control device 1 in this embodiment can prevent the temperature of the low-voltage battery 10 from falling outside the appropriate temperature range.

[0131] Furthermore, the first temperature control system 14 of the battery temperature control device in this embodiment includes a three-way valve 20. The first port 32 of the three-way valve 20 is in communication with the air intake 28, the second port 34 of the three-way valve 20 is in communication with the air heater 30, and the third port 36 of the three-way valve 20 is in communication with the low-voltage battery 10. The three-way valve 20 is configured to switch between a first state in which at least the first port 32 and the third port 36 are in communication, and a second state in which the second port 34 and the third port 36 are in communication. As a result, the battery temperature control device 1 in this embodiment can reliably control the temperature of the low-voltage battery 10 by the first temperature control system 14, both when the temperature of the low-voltage battery 10 is higher than the upper limit temperature of the appropriate temperature range and when it is lower than the lower limit temperature.

[0132] Embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these embodiments. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention. [Explanation of Symbols]

[0133] 1. Battery temperature control device 2 vehicles 10 Low-voltage batteries 12 High-voltage batteries 14 1st temperature control system 16 Second temperature control system 18 Control device 20 Three-way valve 22. Duct No. 1 24. Duct No. 2 26. Third Duct 28 Air intake 30 Air heaters 32 Port 1 34 Port 2 36 Third Port 38 Internal flow path 50 1st heat exchanger 52 Second heat exchanger 110 processors 112 memory

Claims

1. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Control device and Equipped with, The aforementioned second temperature control system is A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The control device is One or more processors, One or more memories connected to the processor, It has, The aforementioned processor, If the temperature of the low-voltage battery is higher than the upper limit temperature of the appropriate temperature range, the temperature of the air supplied to the first temperature control system is compared with the temperature of the low-voltage battery. If the temperature of the air supplied to the first temperature control system is lower than the temperature of the low-voltage battery, the first temperature control system will perform cooling of the low-voltage battery. If the temperature of the air supplied to the first temperature control system is equal to or greater than the temperature of the low-voltage battery, the second temperature control system will perform cooling of the low-voltage battery. Execute the process that includes Battery temperature control device.

2. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Control device and Equipped with, The aforementioned second temperature control system is A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The control device is One or more processors, One or more memories connected to the processor, It has, The first temperature control system includes an air heater that heats the air supplied to the first temperature control system. The aforementioned processor, If the temperature of the low-voltage battery is lower than the lower limit temperature of the appropriate temperature range, the temperature of the heated air, which is the air heated by the air heater, is compared with the temperature of the low-voltage battery. If the temperature of the heated air is higher than the temperature of the low-voltage battery, the first temperature control system will perform heating of the low-voltage battery. If the temperature of the heated air is below the temperature of the low-voltage battery, the second temperature control system will perform heating of the low-voltage battery. Execute the process that includes Battery temperature control device.

3. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Control device and Equipped with, The aforementioned second temperature control system is A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The control device is One or more processors, One or more memories connected to the processor, It has, The first temperature control system includes an air heater that heats the air supplied to the first temperature control system. The aforementioned processor, When the temperature of the low-voltage battery is within the appropriate temperature range, the temperature of the mixture of heated air, which is air heated by the air heater among the air supplied to the first temperature control system, and unheated air, which is air supplied to the first temperature control system that has not been heated by the air heater, is derived. To determine whether the temperature of the mixture is within the appropriate temperature range for the low-voltage battery, If the temperature of the mixture is within the appropriate temperature range for the low-voltage battery, the mixture is supplied to the low-voltage battery to maintain the temperature of the low-voltage battery within the appropriate temperature range. A battery temperature control device that performs processing including the following.

4. The high-voltage battery installed in the vehicle, The low-voltage battery installed in the aforementioned vehicle, A first temperature control system capable of adjusting the temperature of the low-voltage battery by air supplied from outside the vehicle, A second temperature control system, which is different from the first temperature control system, and which can adjust the temperature of the high-voltage battery using a heat transfer medium circulating inside the vehicle, Equipped with, The aforementioned second temperature control system is A first heat exchanger capable of heat exchange between the high-voltage battery and the heat transfer medium, A second heat exchanger capable of heat exchange between the low-voltage battery and the heat transfer medium, It has, The configuration allows for temperature adjustment of the low-voltage battery by the heat transfer medium supplied to the second heat exchanger. The first temperature control system is, An air intake port for obtaining air from outside the vehicle, An air heater for heating the air supplied to the first temperature control system, A three-way valve having a first port, a second port, and a third port, and capable of switching the internal flow path connected to the first port, the second port, and the third port, A first duct that connects the first port of the three-way valve to the intake port, A second duct connecting the second port of the three-way valve and the air heater, A third duct that connects the third port of the three-way valve to the low-voltage battery, It has, The three-way valve is configured to switch between a first state in which the first port and the third port are in communication, and a second state in which the second port and the third port are in communication. Battery temperature control device.

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