Battery cooling system

Abstract

To provide a battery cooling system which can improve cooling efficiency of a battery.SOLUTION: A cooling system 20 comprises: a battery 21 which supplies a motor for driving of a vehicle 10 with electric power; an inlet duct 23 with an introduction port 23a opened in a cabin which supplies the battery 21 with air introduced from the introduction port 23a; a temperature detection part 30 which detects temperature of the battery 21; a first air conditioner 40 which blows air-conditioned air into a first space S1 in the cabin; a second air conditioner 50 which blows air-conditioned air into a second space S2 that is close to the introduction port 23a relative to the first space S1 in the cabin; and an air conditioning control part 90 which controls behavior of the first air conditioner 40 and the second air conditioner 50. The air conditioning control part 90 performs cooling process which controls behavior of the second air conditioner 50 based on a detection value of the temperature detection part 30 to blow cooled air-conditioned air.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a battery cooling system. [Background technology]

[0002] Hybrid vehicles and electric vehicles have traditionally been equipped with batteries that supply power to the vehicle's drive motor. It is known that battery performance deteriorates as the battery temperature rises.

[0003] Patent Document 1 discloses a vehicle in which a battery in a battery housing housing located at the rear of the vehicle is cooled by cooling air blown out from an air conditioner located in front of the driver's seat.

[0004] The air conditioner has an air outlet located in front of the driver's seat. The air conditioner is equipped with a louver that adjusts the direction of the cooling air blown out from the air outlet and an actuator that drives the louver. A thermistor that detects the battery temperature is attached to the battery. The battery housing has a cool air intake duct that draws in air from the passenger compartment using an intake fan. The cool air intake duct opens toward the ceiling of the vehicle.

[0005] In the vehicle described in Patent Document 1, when the battery temperature exceeds a predetermined temperature, the louvers are adjusted so that cooling air is blown toward the ceiling. The cooling air blown toward the ceiling travels along the ceiling toward the rear of the vehicle and is then introduced into the battery housing through a cool air intake duct. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-89569 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the vehicle described in Patent Document 1, as the overall length of the vehicle increases, the path that the cooling air blown out from the air outlet takes to reach the battery becomes longer. This may result in the temperature of the cooling air decreasing before it reaches the battery, or the cooling air having difficulty reaching the battery. Therefore, there is room for improvement in terms of cooling the battery. [Means for solving the problem]

[0008] Various aspects of a battery cooling system for solving the above problems will be described. [Mode 1] A battery cooling system comprising: a battery that supplies power to a vehicle's drive motor; a supply path having an inlet opening into the vehicle cabin and supplying air introduced from the inlet to the battery; a temperature detection unit that detects the temperature of the battery; a first air conditioning unit that blows conditioned air into a first space within the vehicle cabin; a second air conditioning unit that blows conditioned air into a second space within the vehicle cabin that is closer to the inlet than the first space; and an air conditioning control unit that controls the operation of the first air conditioning unit and the second air conditioning unit, wherein the air conditioning control unit is configured to perform a cooling process that controls the operation of the second air conditioning unit so that cooled conditioned air is blown out based on the detection value of the temperature detection unit.

[0009] According to the above configuration, when the cooling process is performed, the second air conditioner blows cooled conditioned air into the second space. The second space is closer to the inlet than the first space from which the first air conditioner blows conditioned air. Therefore, the conditioned air blown out from the second air conditioner is more likely to reach the battery earlier than the conditioned air blown out from the first air conditioner. This improves the cooling efficiency of the battery.

[0010] [Aspect 2] A battery cooling system as described in [Aspect 1], which is provided with an operating unit for setting the temperature and air volume of the conditioned air blown out from the second air conditioning unit, and when the temperature of the conditioned air of the second air conditioning unit set during the previous operation of the operating unit is set to the most recently set temperature, the cooling process includes a process of adjusting the air volume of the conditioned air of the second air conditioning unit without changing the most recently set temperature.

[0011] According to the above configuration, when the second air conditioner blows out cooled conditioned air during the cooling process, the air volume of the conditioned air is adjusted without changing the temperature of the conditioned air. This prevents the temperature in the vehicle cabin from dropping excessively due to a drop in the temperature of the conditioned air. This prevents a decrease in passenger comfort.

[0012] [Aspect 3] The battery cooling system described in [Aspect 2], wherein the air volume of the conditioned air of the second air conditioning unit required to cool the battery is the required air volume determined for each set temperature of the conditioned air of the second air conditioning unit, and the air volume of the conditioned air of the second air conditioning unit set at the time of the previous operation of the operating unit is the most recent set air volume, the cooling process includes a process of changing the air volume of the conditioned air of the second air conditioning unit to be equal to or greater than the required air volume corresponding to the most recent set temperature if the most recent set air volume is less than the required air volume corresponding to the most recent set temperature, and not changing the air volume of the conditioned air of the second air conditioning unit if the most recent set air volume is equal to or greater than the required air volume corresponding to the most recent set temperature.

[0013] According to the above configuration, when the cooling process is performed, the volume of conditioned air from the second air conditioner is equal to or greater than the required volume of air corresponding to the immediately preceding temperature setting. This prevents the volume of conditioned air from the second air conditioner being insufficient to be supplied to the battery. This improves the cooling efficiency of the battery.

[0014] Furthermore, with the above configuration, if the immediately preceding set air volume is equal to or greater than the required air volume corresponding to the immediately preceding set temperature, the air volume of the conditioned air is not changed. This prevents the temperature in the vehicle cabin from dropping excessively due to an increase in the air volume of the conditioned air. This also prevents the operating noise of the second air conditioner from becoming excessively loud. This prevents a decrease in passenger comfort.

[0015] [Aspect 4] A battery cooling system according to [Aspect 3], wherein the required air volume is set to be smaller as the set temperature is lower. According to the above configuration, the lower the set temperature of the second air conditioner, the smaller the required air volume, which prevents the air volume of low-temperature conditioned air from increasing. This prevents the temperature in the vehicle cabin from dropping excessively. Therefore, it is possible to improve the cooling efficiency of the battery while preventing a decrease in passenger comfort.

[0016] [Aspect 5] A battery cooling system described in any one of [Aspect 1] to [Aspect 4], wherein the air conditioning control unit is configured to perform the cooling process only while the first air conditioner is operating.

[0017] According to the above configuration, when the cooling process is performed, both the first air conditioner and the second air conditioner are operated, thereby blowing conditioned air from both the first space and the second space, thereby enabling the battery to be cooled quickly.

[0018] [Aspect 6] A battery cooling system described in any one of [Aspect 1] to [Aspect 5], further comprising an operating unit for setting the temperature and air volume of the conditioned air blown out from the second air conditioning unit, and wherein the air conditioning control unit prioritizes controlling the operation of the second air conditioning unit based on the operation of the operating unit when the operating unit is operated while the cooling process is being performed.

[0019] According to the above configuration, while the cooling process is being performed, the operation of the second air conditioner based on the operation of the operating unit is given priority. This prevents the second air conditioner from continuing to operate in a state that is different from the occupant's intention. This prevents a decrease in occupant comfort. [Effects of the Invention]

[0020] According to the present invention, the cooling efficiency of the battery can be improved. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram of a vehicle equipped with a cooling system according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram of the cooling system of FIG. [Figure 3] FIG. 3 is a block diagram showing the configuration of the air conditioning control unit and the battery control unit shown in FIG. [Figure 4] FIG. 4 is a flowchart showing the procedure of the cooling process. [Figure 5] FIG. 5 is a table showing the relationship between the set temperature of the second air conditioner and the required air volume. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, an embodiment of a battery cooling system will be described with reference to FIGS. First, a vehicle 10 to which a battery cooling system (hereinafter simply referred to as a cooling system 20) is applied will be described.

[0023] Hereinafter, the front and rear in the longitudinal direction of the vehicle 10 will be simply referred to as "front" and "rear", respectively. (Configuration of vehicle 10) As shown in Fig. 1, a vehicle 10 includes a first seat 11, a second seat 12, and a third seat 13. The first seat 11 includes a driver's seat and a passenger seat. The second seat 12 is disposed behind the first seat 11. The third seat 13 is disposed behind the second seat 12.

[0024] The vehicle 10 includes a battery 21 that supplies power to a drive motor (not shown) of the vehicle 10. The vehicle 10 is a hybrid vehicle or an electric vehicle. The vehicle 10 is equipped with a pair of front side doors 14 and a pair of rear side doors 15. The pair of front side doors 14 open and close entrance / exit doors 14a provided on both sides of the first seat 11 in the vehicle width direction, respectively. The pair of rear side doors 15 open and close entrance / exit doors 15a provided on both sides of the second seat 12 in the vehicle width direction, respectively.

[0025] The vehicle 10 has a pair of side walls 16. The side walls 16 are provided on both sides of the third seat 13 in the vehicle width direction. The side walls 16 are provided adjacent to each other behind the rear side door 15. The side walls 16 are portions of the vehicle body where the boarding / exiting doors 14a, 15a are not provided. The side walls 16 form the design surfaces of the interior of the vehicle.

[0026] (Configuration of cooling system 20) The cooling system 20 is a system that cools a battery 21 mounted on the vehicle 10. The cooling system 20 includes the battery 21, a temperature detection unit 30, a first air conditioner 40, a second air conditioner 50, an operation unit 70, a battery control unit 80, and an air conditioning control unit 90. The temperature detection unit 30 detects the temperature of the battery 21. The first air conditioner 40 and the second air conditioner 50 blow conditioned air into the vehicle cabin. The operation unit 70 is a device for setting the temperature and air volume of the conditioned air blown out from the first air conditioner 40 and the temperature and air volume of the conditioned air blown out from the second air conditioner 50. The battery control unit 80 monitors the battery status, including the charging rate and temperature of the battery 21, and controls the charging and discharging of the battery 21. The air conditioning control unit 90 controls the operation of the first air conditioner 40 and the second air conditioner 50 based on operation of the operation unit 70.

[0027] (Configuration of battery 21 and its surroundings) The battery 21 is, for example, a secondary battery such as a lithium ion battery or a nickel-metal hydride battery.

[0028] The battery 21 is housed in a case 22. The case 22 is disposed below the third seat 13, for example. For example, a pair of intake ducts 23 are connected to the case 22. Each intake duct 23 has an inlet 23a that opens to a portion of the side wall 16 facing the occupant seated in the third seat 13. The inlet 23a of the pair of intake ducts 23 opens to each of the pair of side walls 16. The pair of intake ducts 23 communicates between the space inside the vehicle cabin and the space inside the case 22. Note that, for convenience, only one of the pair of intake ducts 23 is shown in FIG. 1. The intake duct 23 is an example of a "supply path."

[0029] An exhaust duct 24 is connected to the case 22. The exhaust duct 24 has an exhaust port that opens into a luggage compartment (not shown) provided at the rear of the vehicle 10. The exhaust duct 24 connects the space inside the case 22 with the space inside the luggage compartment.

[0030] A cooling blower 25 is disposed inside the case 22 between each intake duct 23 and the battery 21. When the cooling blower 25 is driven, air from within the vehicle cabin is introduced into the case 22 through each intake duct 23, and the air from the case 22 is exhausted to the outside through the exhaust duct 24. In this way, the air from within the vehicle cabin is supplied to the battery 21.

[0031] The operation of the cooling blower 25 is controlled by the battery control unit 80. (Configuration of temperature detection unit 30) The temperature detection unit 30 has a first temperature sensor 31 and a second temperature sensor 32. The first temperature sensor 31 is attached to the battery 21. The second temperature sensor 32 is attached inside the case 22. The first temperature sensor 31 detects the temperature of the battery 21. The second temperature sensor 32 detects the temperature of the air introduced into the case 22 through each intake duct 23. The first temperature sensor 31 outputs a detection signal indicating the temperature of the battery 21 to the battery control unit 80. The second temperature sensor 32 outputs a detection signal indicating the temperature of the air introduced into the case 22 to the battery control unit 80.

[0032] Hereinafter, the temperature detected by the first temperature sensor 31 will be referred to as the battery temperature Tb, and the temperature detected by the second temperature sensor 32 will be referred to as the intake air temperature Ti. (Configuration of the first air conditioner 40) The first air conditioner 40 is disposed inside the instrument panel 17 provided at the front of the vehicle interior, i.e., on the opposite side from the vehicle interior. The first air conditioner 40 blows conditioned air into a first space S1. The first space S1 is a space located at the front of the vehicle interior and includes a first seat 11.

[0033] As shown in FIG. 2, the first air conditioner 40 includes a first case 41, a first blower 45, a first evaporator 65, and a first heater core . The first case 41 forms a first flow path 42 through which air flows. A partition wall 43 that separates the first flow path 42 into two regions is provided inside the first case 41. Hereinafter, the flow direction of the air flowing through the first flow path 42 may be referred to as a first flow direction.

[0034] The first case 41 has an outside air inlet 41 a, an inside air inlet 41 b, and a switching member 44. The outside air inlet 41a introduces air from outside the vehicle into the first flow path 42. The inside air inlet 41b introduces air from inside the vehicle cabin into the first flow path 42. The switching member 44 is configured to be movable between a position where the outside air inlet 41a is closed and a position where the inside air inlet 41b is closed. The switching member 44 is driven by an actuator (not shown).

[0035] Although not shown in the figures, a plurality of ducts branching off from the first case 41 are connected to a downstream portion of the first case 41 in the first flow direction. Each duct has an outlet that blows air from the first flow path 42 into the vehicle compartment. The outlets include, for example, an outlet that blows air toward the upper body of an occupant seated in the first seat 11, an outlet that blows air toward the feet of the occupant, and an outlet that blows air toward the windshield at the front of the vehicle compartment.

[0036] The first blower 45 is disposed in the first flow path 42 downstream of the outside air inlet 41a and the inside air inlet 41b in the first flow direction. The first blower 45 has a first fan 45a and a first blower motor 45b that drives the first fan 45a. When the first fan 45a is driven, air is introduced into the first flow path 42, and the air in the first flow path 42 is blown out into the vehicle cabin through the outlets of the ducts connected to the first case 41.

[0037] The first evaporator 65 is disposed in the first flow path 42 downstream of the first blower 45 in the first flow direction. The first evaporator 65 is disposed across two regions of the first flow path 42 separated by the partition wall 43. The first evaporator 65 is also one component of the cooling device 60, which will be described later. Air introduced into the first flow path 42 by the first blower 45 is blown onto the first evaporator 65. The first evaporator 65 exchanges heat between the air blown onto the first evaporator 65 and the refrigerant flowing inside the first evaporator 65. As a result, the air blown onto the first evaporator 65 is cooled, and cooled air flows inside the first flow path 42.

[0038] The first heater core 46 is disposed within the first flow path 42, downstream of the first evaporator 65 in the first flow direction. The first heater core 46 is disposed across two regions of the first flow path 42 separated by the partition wall 43. Air that has passed through the first evaporator 65 is blown onto the first heater core 46. The first heater core 46 is heated by a heating device (not shown). The first heater core 46 heats the air flowing within the first flow path 42, i.e., the cooled air cooled by the first evaporator 65.

[0039] Air mix doors 47, 48 are provided in each of the two regions of the first flow path 42 separated by the partition wall 43. Each air mix door 47, 48 is provided downstream of the first evaporator 65 in the first flow direction and upstream of the first heater core 46. Each air mix door 47, 48 has a rotary shaft and a plate-shaped door body connected to the rotary shaft. Rotation of the door body of each air mix door 47, 48 adjusts the ratio between the amount of air that bypasses the first heater core 46 after passing through the first evaporator 65 and the amount of air that passes through the first heater core 46 after passing through the first evaporator 65. This adjusts the temperature of the air flowing through the first flow path 42, allowing cooled air or warm air to be blown out from the outlet of each duct.

[0040] The operation of the first blower motor 45b and the opening degrees of the air mix doors 47 and 48 are controlled by the air conditioning control unit 90. (Configuration of the second air conditioner 50) As shown in FIG. 1, the second air conditioner 50 is disposed inside one of the side walls 16, i.e., on the opposite side from the vehicle interior. The second air conditioner 50 blows conditioned air into the second space S2. The second space S2 is a space within the vehicle interior that is closer to the inlet 23a than the first space S1. The second space S2 is a space located at the rear of the vehicle interior and includes the second seat 12 and the third seat 13. The second space S2 is adjacent to and rear of the first space S1.

[0041] As shown in FIG. 2, the second air conditioner 50 includes a second case 51, a second blower 55, a second evaporator 66, and a second heater core 56. The second case 51 forms a second flow path 52 through which air flows. Hereinafter, the flow direction of the air flowing through the second flow path 52 may be referred to as a second flow direction.

[0042] The second case 51 has an inside air inlet 51a. The inside air inlet 51a introduces air from inside the vehicle compartment into the second flow path 52. 1, a plurality of ducts 53 branching off from the second case 51 are connected to a downstream portion of the second case 51 in the second flow direction. Each duct 53 has an air outlet that blows air from the second flow path 52 into the vehicle cabin. The air outlet includes a first air outlet 53a that blows air toward the upper body of an occupant seated in the third seat 13, and a second air outlet 53b that blows air toward the upper body of an occupant seated in the second seat 12.

[0043] The second air conditioner 50 has a pair of first air outlets 53a and a pair of second air outlets 53b. The pair of first air outlets 53a open to the upper parts of the pair of side walls 16, respectively. Each first air outlet 53a opens to a position higher than the inlet 23a of the intake duct 23 on the side wall 16 where the inlet 23a opens. Each second air outlet 53b opens to a portion of the vehicle interior that is located forward of the respective first air outlets 53a. Note that, for convenience, only some of the multiple ducts 53 are shown in FIG. 1.

[0044] 2, second blower 55 is disposed in second flow path 52 downstream of inside air inlet 51a in the second flow direction. Second blower 55 includes second fan 55a and second blower motor 55b that drives second fan 55a. When second fan 55a is driven, air is introduced into second flow path 52, and the air in second flow path 52 is blown out into the vehicle cabin through the outlets of each duct 53 connected to second case 51.

[0045] The second evaporator 66 is disposed in the second flow path 52 downstream of the second blower 55 in the second flow direction. The second evaporator 66 is also one component of the cooling device 60, which will be described later. Air introduced into the second flow path 52 by the second blower 55 is blown onto the second evaporator 66. The second evaporator 66 exchanges heat between the air blown onto the second evaporator 66 and the refrigerant flowing inside the second evaporator 66. As a result, the air blown onto the second evaporator 66 is cooled, and cooled air flows inside the second flow path 52.

[0046] The second heater core 56 is disposed in the second flow path 52 downstream of the second evaporator 66 in the second flow direction. Air that has passed through the second evaporator 66 is blown onto the second heater core 56. The second heater core 56 is heated by a heating device (not shown). The second heater core 56 heats the air flowing in the second flow path 52, i.e., the cooled air cooled by the second evaporator 66.

[0047] Two air mix doors 57, 58 are provided in the second flow path 52. The air mix door 57 is provided downstream of the second evaporator 66 in the second flow direction and upstream of the second heater core 56. The air mix door 58 is provided downstream of the second evaporator 66 in the second flow direction and aligned with the second heater core 56. Each air mix door 57, 58 has a rotary shaft and a plate-shaped door body connected to the rotary shaft. The rotation of the door body of each air mix door 57, 58 adjusts the ratio between the amount of air that bypasses the second heater core 56 after passing through the second evaporator 66 and the amount of air that passes through the second heater core 56 after passing through the second evaporator 66. This adjusts the temperature of the air flowing in the second flow path 52, allowing cooled air or warm air to be blown out from the outlets of each duct 53.

[0048] The operation of the second blower motor 55b and the opening degrees of the air mix doors 57 and 58 are controlled by the air conditioning control unit 90. (Configuration of cooling device 60) The cooling system 20 includes a cooling device 60 that cools the air in the first flow path 42 and the air in the second flow path 52. The cooling device 60 includes a compressor 61, a condenser 62, a first expansion valve 63, a second expansion valve 64, a first evaporator 65, and a second evaporator 66.

[0049] The compressor 61 compresses the refrigerant circulating inside the cooling device 60. The refrigerant compressed by the compressor 61 and having a high temperature and pressure is sent to the condenser 62. The condenser 62 cools and liquefies the refrigerant sent from the compressor 61 by heat exchange between the refrigerant and outside air. The refrigerant liquefied by the condenser 62 is sent to the first expansion valve 63 and the second expansion valve 64.

[0050] The first expansion valve 63 decompresses the refrigerant sent from the condenser 62 to atomize it and injects it into the first evaporator 65. The second expansion valve 64 decompresses the refrigerant sent from the condenser 62 to atomize it and injects it into the second evaporator 66.

[0051] The first evaporator 65 vaporizes the refrigerant by heat exchange between the refrigerant injected from the first expansion valve 63 and the air flowing in the first flow path 42. The first evaporator 65 is cooled by the heat of vaporization of the refrigerant, thereby cooling the air passing through the first evaporator 65 in the first flow path 42. The refrigerant vaporized by the first evaporator 65 is sent to the compressor 61.

[0052] The second evaporator 66 vaporizes the refrigerant by heat exchange between the refrigerant injected from the second expansion valve 64 and the air flowing in the second flow path 52. The second evaporator 66 is cooled by the heat of vaporization of the refrigerant, thereby cooling the air passing through the second evaporator 66 in the second flow path 52. The refrigerant in the second evaporator 66 is sent to the compressor 61.

[0053] The rotation speed of the compressor 61, the opening degree of the first expansion valve 63, and the opening degree of the second expansion valve 64 are controlled by the air conditioning control unit 90. (Configuration of operation unit 70) 1, the operation unit 70 is disposed, for example, on the instrument panel 17. The operation unit 70 is a device that accepts input operations by the occupant. The operation unit 70 outputs an operation signal based on the input operation by the occupant to the air conditioning control unit 90.

[0054] The first air conditioner 40 and the second air conditioner 50 can be operated by the occupant operating an operation unit 70. The temperature and air volume of the conditioned air blown out from the first air conditioner 40 and the second air conditioner 50 are set by the occupant operating the operation unit 70. The operation unit 70 has the function of setting the first air conditioner 40 and the second air conditioner 50 independently.

[0055] (Configuration of battery control unit 80) The battery control unit 80 includes a CPU and a memory. The CPU executes various processes related to the battery 21 in accordance with programs stored in the memory.

[0056] 3, the battery control unit 80 acquires detection signals from the first temperature sensor 31 and the second temperature sensor 32. The battery control unit 80 controls the operation of the cooling blower 25 based on the detection signals from the first temperature sensor 31 and the second temperature sensor 32.

[0057] When the battery temperature Tb is equal to or higher than the first threshold value Tth1 and the intake air temperature Ti is equal to or higher than the second threshold value Tth2, the battery control unit 80 outputs a cooling request signal to the air conditioning control unit 90. The cooling request signal is a signal that instructs the air conditioning control unit 90 to start executing a cooling process, which will be described later. The battery control unit 80 outputs the cooling request signal and also operates the cooling blower 25.

[0058] The first threshold value Tth1 is, for example, a temperature equal to or higher than a recommended temperature range recommended for use of the battery 21. The second threshold value Tth2 is, for example, a temperature lower than the first threshold value Tth1. The first threshold value Tth1 and the second threshold value Tth2 are determined in advance by experiment or simulation as temperatures at which the battery 21 needs to be cooled in order to suppress deterioration of the performance of the battery 21.

[0059] After outputting the cooling request signal, the battery control unit 80 outputs a cooling end signal to the air conditioning control unit 90 when the battery temperature Tb is equal to or lower than the third threshold value Tth3 and the intake air temperature Ti is equal to or lower than the fourth threshold value Tth4. The cooling end signal is a signal that instructs the air conditioning control unit 90 to end the execution of the cooling process described below. The battery control unit 80 outputs the cooling end signal and stops the operation of the cooling blower 25.

[0060] The third threshold value Tth3 is, for example, a temperature within the recommended temperature range of the battery 21 and lower than the first threshold value Tth1. The fourth threshold value Tth4 is, for example, a temperature lower than the third threshold value Tth3 and lower than the second threshold value Tth2. Note that the third threshold value Tth3 may be a temperature lower than the second threshold value Tth2.

[0061] (Configuration of air conditioning control unit 90) The air conditioning control unit 90 includes a CPU and a memory. The CPU executes various processes related to the first air conditioner 40 and the second air conditioner 50 in accordance with programs stored in the memory.

[0062] The air conditioning control unit 90 receives an operation signal from the operation unit 70. The air conditioning control unit 90 controls the temperature and air volume of the conditioned air in each of the first air conditioner 40 and the second air conditioner 50 based on the operation signal.

[0063] The air conditioning control unit 90 controls the operation of the compressor 61, the first expansion valve 63, the second expansion valve 64, the first blower motor 45b, the second blower motor 55b, and each air mix door 47, 48, 57, 58 based on various requests from the operation unit 70 and the battery control unit 80.

[0064] The air conditioning control unit 90 sets a cooling flag to ON when a cooling request signal is input from the battery control unit 80. The air conditioning control unit 90 sets the cooling flag to OFF when a cooling end signal is input from the battery control unit 80.

[0065] (Cooling process procedure) Next, the procedure of the cooling process executed by the air conditioning control unit 90 to cool the battery 21 will be described with reference to the flowchart shown in FIG.

[0066] The air conditioning control unit 90 executes a cooling process that controls the operation of the second air conditioner 50 so that cooled air is blown out from the second air conditioner 50 based on the detection value of the temperature detection unit 30. The air conditioning control unit 90 repeatedly executes the cooling process at a predetermined control cycle.

[0067] The air conditioning control unit 90 first executes the process of step S101. In step S101, the air conditioning control unit 90 determines whether or not the cooling flag is ON, that is, whether or not a cooling request signal has been input from the battery control unit 80. If the air conditioning control unit 90 determines that the cooling flag is ON (step S101: YES), the process proceeds to step S102. If the air conditioning control unit 90 determines that the cooling flag is not ON, that is, if the air conditioning control unit 90 determines that the cooling flag is OFF (step S101: NO), the air conditioning control unit 90 determines that there is no need to cool the battery 21, and ends the series of processes.

[0068] As described above, when the battery temperature Tb is equal to or higher than the first threshold value Tth1 and the intake air temperature Ti is equal to or higher than the second threshold value Tth2, the cooling flag is set to ON. When the battery temperature Tb is equal to or lower than the third threshold value Tth3 and the intake air temperature Ti is equal to or lower than the fourth threshold value Tth4, the cooling flag is set to OFF. When the cooling flag is set to ON, the cooling blower 25 operates. As a result, the conditioned air blown out from the second air conditioner 50 is supplied to the battery 21.

[0069] In step S102, the air conditioning control unit 90 determines whether the first air conditioner 40 is operating. More specifically, the air conditioning control unit 90 determines whether the compressor 61 is operating and whether the first blower motor 45b is operating. If the air conditioning control unit 90 determines that the first air conditioner 40 is operating (step S102: YES), the process proceeds to step S103. If the air conditioning control unit 90 determines that the first air conditioner 40 is not operating (step S102: NO), the process ends.

[0070] In step S103, the air conditioning control unit 90 determines whether the second air conditioner 50 is not operating. More specifically, the air conditioning control unit 90 determines whether the second blower motor 55b is not driving. If the air conditioning control unit 90 determines that the second air conditioner 50 is not operating (step S103: YES), the process proceeds to step S104. If the air conditioning control unit 90 determines that the second air conditioner 50 is operating (step S103: NO), the process proceeds to step S105.

[0071] In step S104, the air conditioning control unit 90 operates the second air conditioner 50. More specifically, the air conditioning control unit 90 drives the second blower motor 55b. In step S105, the air conditioning control unit 90 acquires the set temperature and set air volume of the conditioned air of the second air conditioner 50. More specifically, the air conditioning control unit 90 acquires the set temperature and set air volume of the conditioned air of the second air conditioner 50 that were set the previous time the operation unit 70 was operated. The air conditioning control unit 90 then proceeds to step S106.

[0072] Hereinafter, the set temperature of the conditioned air of the second air conditioner 50 set during the previous operation of the operating unit 70 will be referred to as the "previously set temperature," and the set air volume of the conditioned air of the second air conditioner 50 set during the previous operation of the operating unit 70 will be referred to as the "previously set air volume."

[0073] In step S106, the air conditioning control unit 90 determines whether the previous set air volume is less than the required air volume corresponding to the previous set temperature. As shown in FIG. 5, the required air volume is the volume of conditioned air required by the second air conditioner 50 to cool the battery 21, determined for each set temperature of the conditioned air of the second air conditioner 50. The required air volume is determined in advance through experiments or simulations. The required air volume is determined to decrease as the set temperature decreases. For example, when the set temperature is "18°C," "20°C," "22°C," "24°C," etc., the required air volumes are "1," "2," "3," "4," etc. Note that "1," "2," "3," "4," etc. in FIG. 5 are indicators indicating the magnitude of the volume of conditioned air of the second air conditioner 50.

[0074] 4, if the air conditioning control unit 90 determines that the immediately preceding set air volume is less than the required air volume corresponding to the immediately preceding set temperature (step S106: YES), the process proceeds to step S107. If the air conditioning control unit 90 determines that the immediately preceding set air volume is not less than the required air volume corresponding to the immediately preceding set temperature, that is, if the air conditioning control unit 90 determines that the immediately preceding set air volume is equal to or greater than the required air volume corresponding to the immediately preceding set temperature (step S106: NO), the process proceeds to step S108.

[0075] In step S107, the air conditioning control unit 90 changes the set air volume of the conditioned air of the second air conditioner 50 to the required air volume corresponding to the immediately preceding set temperature. After that, the air conditioning control unit 90 ends the series of processes.

[0076] In step S107, for example, if the previous set temperature is 22°C and the previous set air volume is equal to or less than 2, the previous set air volume is less than the required air volume corresponding to the previous set temperature. Therefore, the air conditioning control unit 90 changes the set air volume of the conditioned air of the second air conditioner 50 to 3.

[0077] In step S108, the air conditioning control unit 90 maintains the set air volume of the second air conditioner 50, that is, does not change the air volume of the conditioned air of the second air conditioner 50. After that, the air conditioning control unit 90 ends the series of processes.

[0078] In step S108, for example, if the previous set temperature is "22°C" and the previous set airflow rate is "3" or higher, the previous set airflow rate is equal to or higher than the required airflow rate corresponding to the previous set temperature. Therefore, the air conditioning control unit 90 maintains the set airflow rate of the conditioned air of the second air conditioner 50 at "3" or higher without changing it.

[0079] As described above, the air conditioning control unit 90 adjusts the air volume of the conditioned air of the second air conditioner 50 in accordance with the previous set temperature and previous set air volume without changing the previous set temperature. Incidentally, if the operation unit 70 is operated while the cooling process is being performed, the air conditioning control unit 90 prioritizes control of the operation of the second air conditioner 50 based on the operation of the operation unit 70. In other words, if an occupant operates the operation unit 70 to change the settings of the second air conditioner 50 while the cooling process is being performed, the air conditioning control unit 90 ends the cooling process and controls the second air conditioner 50 based on the changed settings. Note that even if the cooling process has ended, if the ignition switch of the vehicle 10 is turned OFF and then ON again, the air conditioning control unit 90 can execute the cooling process again.

[0080] <Operation of this embodiment> When the cooling process is performed, the second air conditioner 50 blows the cooled conditioned air into the second space S2. The second space S2 is closer to the inlet 23a than the first space S1 from which the first air conditioner 40 blows the conditioned air. Therefore, the conditioned air blown out from the second air conditioner 50 is more likely to reach the battery 21 earlier than the conditioned air blown out from the first air conditioner 40.

[0081] <Effects of this embodiment> (1) The air conditioning control unit 90 executes a cooling process based on the detected value of the temperature detection unit 30 to control the operation of the second air conditioner 50 so that cooled conditioned air is blown out.

[0082] According to the above configuration, the cooling efficiency of the battery 21 can be improved. (2) The air conditioning control unit 90 adjusts the volume of conditioned air from the second air conditioner 50 without changing the immediately preceding temperature setting.

[0083] According to the above configuration, when the second air conditioner 50 blows out cooled conditioned air during the cooling process, the air volume of the conditioned air is adjusted without changing the temperature of the conditioned air. This prevents the temperature in the vehicle cabin from dropping excessively due to a drop in the temperature of the conditioned air. This prevents a decrease in passenger comfort.

[0084] (3) When the previously set air volume is less than the required air volume corresponding to the previously set temperature, the air conditioning control unit 90 changes the air volume of the conditioned air of the second air conditioner 50 to the required air volume corresponding to the previously set temperature. When the previously set air volume is equal to or greater than the required air volume corresponding to the previously set temperature, the air conditioning control unit 90 does not change the air volume of the conditioned air of the second air conditioner 50.

[0085] According to the above configuration, when the cooling process is performed, the air volume of the conditioned air from the second air conditioner 50 becomes equal to or greater than the required air volume corresponding to the immediately preceding set temperature. This makes it possible to prevent the air volume of the conditioned air from the second air conditioner 50 supplied to the battery 21 from becoming insufficient. This makes it possible to improve the cooling efficiency of the battery 21.

[0086] Furthermore, with the above configuration, if the immediately preceding set air volume is equal to or greater than the required air volume corresponding to the immediately preceding set temperature, the air volume of the conditioned air from the second air conditioner 50 is not changed. This prevents the temperature in the vehicle cabin from dropping excessively as the air volume of the conditioned air increases. Also, this prevents the operating noise of the second air conditioner 50 from becoming excessively loud. This prevents a decrease in passenger comfort.

[0087] (4) The required air volume is set to be smaller as the set temperature of the second air conditioner 50 is lower. According to the above configuration, the lower the set temperature of the second air conditioner 50, the smaller the required air volume becomes, so that an increase in the air volume of low-temperature conditioned air can be suppressed. This prevents the temperature in the vehicle cabin from dropping excessively. Therefore, it is possible to improve the cooling efficiency of the battery 21 while suppressing a decrease in passenger comfort.

[0088] (5) The air conditioning control unit 90 executes the cooling process only while the first air conditioner 40 is operating. According to the above configuration, when the cooling process is performed, both the first air conditioner 40 and the second air conditioner 50 operate. As a result, conditioned air is blown out from both the first space S1 and the second space S2. Therefore, the cooling of the battery 21 can be completed quickly.

[0089] (6) If the operation unit 70 is operated while the cooling process is being performed, the air conditioning control unit 90 prioritizes control of the operation of the second air conditioner 50 based on the operation of the operation unit 70. According to the above configuration, while the cooling process is being performed, priority is given to the operation of the second air conditioner 50 based on the operation of the operating unit 70. This prevents the second air conditioner 50 from continuing to operate in a state that is different from the occupant's intention, thereby preventing a decrease in occupant comfort.

[0090] (7) The air conditioning control unit 90 executes the cooling process when the battery temperature Tb is equal to or higher than the first threshold value Tth1 and the intake air temperature Ti is equal to or higher than the second threshold value Tth2. The second threshold value Tth2 is a temperature lower than the first threshold value Tth1.

[0091] According to the above configuration, when the battery temperature Tb is equal to or higher than the first threshold value Tth1 and the intake air temperature Ti is lower than the second threshold value Tth2, the cooling process is not executed. That is, when the battery temperature Tb is high and the intake air temperature Ti is low, the cooling process is not executed. This reduces the frequency with which the cooling process is executed. As a result, the generation of operating noise from the second air conditioner 50 and the decrease in fuel efficiency of the vehicle 10 can be suppressed.

[0092] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0093] The air conditioning control unit 90 may disable operation of the operation unit 70 while the cooling process is being performed. This prevents a shortage of conditioned air reaching the battery 21, i.e., a rise in the temperature of the battery 21, caused by the cooling process being terminated by operation of the operation unit 70.

[0094] The air conditioning control unit 90 may execute the cooling process while the first air conditioner 40 is not operating. That is, only the second air conditioner 50 may be operating while the cooling process is being executed. In this case, step S102 in the cooling process is omitted.

[0095] The required airflow may be determined for each of a plurality of set temperature ranges. In this case, it is preferable that the required airflow be set so that it is smaller for a set temperature range that includes a lower temperature. During the cooling process, if the previously set air volume is less than the required air volume corresponding to the previously set temperature, the air conditioning control unit 90 may increase the air volume of the conditioned air from the second air conditioner 50 to be greater than the required air volume corresponding to the previously set temperature.

[0096] During the cooling process, the air conditioning control unit 90 may change the air volume of the conditioned air from the second air conditioner 50 to a predetermined required air volume, regardless of the immediately preceding set air volume. During the cooling process, if the previously set air volume is greater than the required air volume corresponding to the previously set temperature, the air conditioning control unit 90 may change the air volume of the conditioned air from the second air conditioner 50 to the required air volume corresponding to the previously set temperature.

[0097] During the cooling process, the air conditioning control unit 90 may adjust the set temperature and set air volume of the second air conditioner 50 based on the detection value of the temperature detection unit 30. For example, if the immediately preceding set temperature is equal to or higher than a predetermined temperature, the air conditioning control unit 90 may change the temperature of the conditioned air of the second air conditioner 50 to a temperature lower than the predetermined temperature, and then adjust the air volume of the conditioned air.

[0098] The case 22 may be connected to an intake duct 23 that opens only to the side wall 16 located on one side of the third seat 13 in the vehicle width direction. The inlet 23a of the intake duct 23 may be open at any position in the second space S2.

[0099] The second temperature sensor 32 may be mounted inside the intake duct 23. The first air outlet 53a is not limited to an outlet that opens in the side wall 16, as long as it is capable of blowing air into the second space S2, and may be an outlet that opens in the ceiling of the vehicle interior, for example.

[0100] The exhaust duct 24 may be configured to exhaust the air inside the case 22 to the outside of the vehicle. The battery 21 may be located at any position in the vehicle 10. The second space S2 does not have to be a space adjacent to the first space S1. That is, another space may exist between the first space S1 and the second space S2.

[0101] In addition to the first air conditioner 40 and the second air conditioner 50, the cooling system 20 may include other air conditioners. The cooling system 20 may have a control unit that controls each of the first air conditioner 40 and the second air conditioner 50.

[0102] The air conditioning control unit 90 may be configured as a circuit including one or more processors that execute various processes according to a computer program (software). The air conditioning control unit 90 may also be configured as a circuit including one or more dedicated hardware circuits, such as an application-specific integrated circuit (ASIC), that execute at least some of the various processes, or a combination thereof. The processor includes a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to execute the processes. The memory, i.e., computer-readable medium, includes any medium accessible by a general-purpose or dedicated computer. This modification can also be applied to the battery control unit 80. [Explanation of symbols]

[0103] S1…first space S2…Second space 10...Vehicle 20...Cooling system 21...Battery 23...Intake duct (supply path) 23a...Entrance 30...Temperature detection unit 40...1st air conditioner 50…Second air conditioner 70...Operation unit 90...Air conditioning control unit

Claims

1. a battery that supplies power to a drive motor of the vehicle; a supply path having an inlet opening into the vehicle interior, the supply path supplying air introduced through the inlet to the battery; a temperature detection unit that detects the temperature of the battery; a first air conditioner that blows conditioned air into a first space in the vehicle cabin; a second air conditioner that blows conditioned air into a second space within the vehicle interior that is closer to the inlet than the first space; an air conditioning control unit that controls the operation of the first air conditioner and the second air conditioner, The air conditioning control unit is configured to execute a cooling process to control the operation of the second air conditioner based on the detection value of the temperature detection unit so that cooled conditioned air is blown out. Battery cooling system.

2. an operation unit for setting the temperature and air volume of the conditioned air blown out from the second air conditioner; When the temperature of the conditioned air of the second air conditioner set at the time of the previous operation of the operating unit is set as the immediately preceding set temperature, the cooling process includes a process of adjusting the air volume of the conditioned air of the second air conditioner without changing the immediately preceding set temperature. The battery cooling system of claim 1 .

3. a required air volume is an air volume of the conditioned air of the second air conditioner required to cool the battery, the air volume of the conditioned air being determined for each set temperature of the conditioned air of the second air conditioner; When the air volume of the conditioned air of the second air conditioner set at the time of the previous operation of the operating unit is set to the most recently set air volume, The cooling process includes a process of changing the air volume of the conditioned air of the second air conditioner to equal to or greater than the required air volume corresponding to the immediately preceding set temperature when the immediately preceding set air volume is less than the required air volume corresponding to the immediately preceding set temperature, and not changing the air volume of the conditioned air of the second air conditioner when the immediately preceding set air volume is equal to or greater than the required air volume corresponding to the immediately preceding set temperature. The battery cooling system of claim 2 .

4. The required air volume is set to be smaller as the set temperature is lower. The battery cooling system of claim 3 .

5. The air conditioning control unit is configured to perform the cooling process only while the first air conditioner is operating. The battery cooling system of claim 1 .

6. an operation unit for setting the temperature and air volume of the conditioned air blown out from the second air conditioner; When the operation unit is operated during the execution of the cooling process, the air conditioning control unit prioritizes control of the operation of the second air conditioner based on the operation of the operation unit. The battery cooling system according to any one of claims 1 to 5.

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