Vehicle battery temperature conditioning system

Abstract

To suppress increase in power consumption while performing battery temperature conditioning that takes battery deterioration into account.SOLUTION: A control section 11: predicts travel information of a vehicle from when a vehicle departs from a present location till arrival at a destination; determines whether travel time of the vehicle exceeds a threshold on the basis of the predicted travel information; executes first battery temperature conditioning control when determining that the travel time of the vehicle exceeds the threshold; and executes second battery temperature conditioning control when determining that the travel time of the vehicle does not exceed the threshold. Therefore, increase in power consumption due to unnecessary temperature conditioning within an optimal range may be suppressed, when a battery 12 is used for a short period while executing temperature conditioning of the battery 12 within the optimal range taking into account deterioration of the battery 12 when the same is used for a long period.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a battery temperature control system for vehicles.

Background Art

[0002] A vehicle battery temperature control system for controlling the temperature of a battery mounted on a vehicle is known. For example, Patent Document 1 discloses a technique for changing the target battery temperature of temperature control performed on a battery from an initial value based on vehicle usage information. Further, Patent Document 2 discloses a technique for executing optimal control of battery temperature according to load prediction incorporating the needs of passengers and the battery.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a vehicle battery temperature control system that can suppress an increase in power consumption while performing temperature control of a battery in consideration of battery degradation.

Means for Solving the Problems

[0005] According to one aspect of the present invention, a battery temperature control system for a vehicle includes a battery mounted on the vehicle, a battery temperature control unit for controlling the temperature of the battery, and a control unit capable of executing battery temperature control for controlling the temperature of the battery. The control unit predicts the driving information of the vehicle from the time the vehicle departs from the current location until it arrives at the destination, determines whether the driving time of the vehicle exceeds a threshold based on the predicted driving information, executes first battery temperature control when it is determined that the driving time of the vehicle exceeds the threshold, and executes second battery temperature control when it is determined that the driving time of the vehicle does not exceed the threshold.

Effects of the Invention

[0006] According to the present invention, it is possible to provide a battery temperature control system for a vehicle that can suppress an increase in power consumption while performing temperature control of the battery in consideration of battery degradation.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0008] [Configuration of Battery Temperature Control System for Vehicle] The vehicle battery temperature control system according to this embodiment is configured to suppress an increase in power consumption while performing temperature control of the battery in consideration of battery degradation. Further, the vehicle battery temperature control system according to this embodiment is configured to suppress energy consumption.

[0009] FIG. 1 is an explanatory diagram showing an outline of a configuration example of a vehicle battery temperature control system 1 according to this embodiment.

[0010] The vehicle battery temperature control system 1 is for temperature control of a battery mounted on an electric vehicle EV (EV: Electric Vehicle) such as an electric vehicle or a hybrid vehicle. The vehicle battery temperature control system 1 is incorporated in a vehicle air conditioner for air-conditioning the vehicle interior.

[0011] The vehicle battery temperature control system 1 includes a battery temperature control circuit 10 and a control unit 11.

[0012] The battery temperature control circuit 10 is a part of a heat medium circuit used for air-conditioning the vehicle interior. The battery temperature control circuit 10 includes a battery 12, a battery temperature control unit 13 for temperature control of the battery 12, a circulation pump 14 for extruding the heat medium, and a heat medium heating device 15 for heating the heat medium.

[0013] When the battery 12 is charged and discharged, the battery temperature rises due to self-heating of the battery 12. Therefore, the battery temperature control circuit 10 performs temperature control (temperature regulation) of the battery 12 to prevent degradation and performance deterioration of the battery 12. In this embodiment, a lithium-ion battery is used as the battery 12. Note that a battery other than a lithium-ion battery may be used as the battery 12.

[0014] The heat medium of the battery temperature control circuit 10 circulates due to the operation of the circulation pump 14. In the battery temperature control circuit 10, the temperature of the battery 12 is adjusted by the heat medium circulating through the battery temperature control circuit 10. The heat medium flowing through the battery temperature control circuit 10 can exchange heat with the refrigerant flowing through the refrigerant circuit 16. The refrigerant circuit 16 includes a compressor, a high-temperature side heat exchanger, a decompression device, and a low-temperature side heat exchanger. The refrigerant circuit 16 is configured to function as a heat pump that circulates the refrigerant and repeats compression, condensation, expansion, and evaporation. The heat medium that exchanges heat with the refrigerant in the refrigerant circuit 16 is used for air conditioning in the vehicle interior, temperature control of the battery 12, and temperature control of the motor, etc.

[0015] The control unit 11 is a microcomputer equipped with a processor, a memory, and an input / output interface. The control unit 11 is capable of executing battery temperature control for controlling the temperature of the battery 12. The control unit 11 is capable of controlling the operations of the heat medium circuit including the battery temperature control circuit 10 and the refrigerant circuit 16. When executing the battery temperature control, the control unit 11, for example, switches the heat medium circuit so that the heat medium of the battery temperature control circuit 10 can exchange heat with the refrigerant of the refrigerant circuit 16, or switches the heat medium circuit so that the heat medium circulates between the battery temperature control circuit 10 and the radiator circuit, or switches the heat medium circuit so that the heat medium circulates through the battery temperature control circuit 10 separated from other circuits.

[0016] Detection signals from various sensors 17 are input to the control unit 11. The sensors 17 include an internal air temperature sensor that measures the temperature of the air in the vehicle interior, an outside air temperature sensor that detects the outside air temperature, etc.

[0017] The control unit 11 can transmit and receive data (such as estimated arrival time data, driving route data, weather information data, etc.) with the ECU of the navigation device 19 provided in the vehicle via the communication bus 18. Note that the control unit 11 can also obtain necessary data (such as vehicle speed) from other ECUs (not shown) of the vehicle through the communication bus 18. In addition to the information obtained from the vehicle's ECU, the control unit 11 can also acquire detailed route information such as height differences and traffic jam information from the cloud, other vehicles, infrastructure facilities, etc. through V2X communication.

[0018] [Battery Temperature Control] In this embodiment, a lithium-ion battery is used as the battery 12. The optimal temperature of the lithium-ion battery is around 25°C ± 5°C (that is, in the range of 20°C to 30°C). Therefore, when using a lithium-ion battery, it is preferable to perform temperature management around 25°C ± 5°C. However, generally, it is said that even when temperature management is performed within the allowable temperature range of 0°C to 40°C for a lithium-ion battery, the impact on battery performance and lifespan is small. Therefore, in this embodiment, taking advantage of such characteristics, battery temperature control according to the driving time of the vehicle is executed for the battery 12. Thereby, the power consumption associated with the temperature control of the battery 12 can be reduced, or the energy consumption associated with the temperature control of the battery 12 can be suppressed.

[0019] Note that the vehicle battery temperature control system 1 of this embodiment is equipped with a protection function for the battery 12. Specifically, when the elapsed time since the user stopped driving is long, it is assumed that the battery temperature = outside air temperature. And when the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range, it will cause thermal runaway and deterioration. Also, when the temperature of the battery 12 exceeds the lower limit value of the allowable range, it will cause a decrease in the performance of the battery 12. Therefore, when the battery temperature < 0°C or 40°C < battery temperature, the battery protection function on the vehicle side is activated so that 0°C ≤ battery temperature ≤ 40°C. Specifically, when the battery temperature < 0°C, the control unit 11 forcibly heats the battery 12, and when 40°C < battery temperature, the control unit 11 forcibly cools the battery 12. Therefore, it is assumed that the battery temperature control described below is executed within the range of 0°C or more and 40°C or less.

[0020] Hereinafter, the battery temperature control of the first embodiment and the battery temperature control of the second embodiment that can be executed by the control unit 11 will be described. Either one of the controls may be implemented, or both controls may be implemented.

[0021] Note that in this embodiment, the optimal range of the temperature of the battery 12 will be described as a range in which the deterioration and performance of the battery 12 are less affected than the allowable range. In this embodiment, 20°C to 30°C is cited as an example of the optimal range, and 0°C to 40°C is cited as an example of the allowable range. The optimal range and the allowable range are not limited to this embodiment and can be set as appropriate.

[0022] <Battery Temperature Control of the First Embodiment> When the driving time of the vehicle is short, it is assumed that the effect of suppressing the deterioration of the battery 12 is small compared to the power consumption required for temperature management of the battery 12 within the optimal temperature range. That is, when performing temperature management of the battery 12 within the optimal temperature range, the power consumption increases due to factors such as the need to increase the rotational speed of the compressor to enhance the heat absorption effect of the refrigerant. On the other hand, in the case of short driving, since the usage time of the battery 12 is short, it is assumed that even if the temperature of the battery 12 does not fall within the optimal temperature range, the impact on the deterioration of the battery 12 is small or almost non-existent. Therefore, it is preferable to perform battery temperature management considering the cost-effectiveness of the power consumed when executing battery temperature control for suppressing the deterioration of the battery 12. Thus, the control unit 11 is capable of executing the battery temperature control shown in FIG. 2.

[0023] FIG. 2 is a flowchart showing an example of battery temperature control by the control unit 11.

[0024] As shown in FIG. 2, the control unit 11 acquires driving information of the vehicle (S1). The driving information is, for example, the remaining battery level, battery temperature, outside air temperature, driving distance, and driving time. This information can be obtained based on departure information, destination information, route information obtained from learning data, settings for the navigation device 19, data acquired from the cloud, data by communication with other vehicles, data acquired from infrastructure facilities, etc.

[0025] Next, the control unit 11 predicts the transition of the battery temperature rise based on the driving information, and predicts the temperature of the battery 12 when the vehicle arrives at the destination based on the predicted transition of the battery temperature rise (S2). Specifically, the control unit 11 predicts the timing of the charge / discharge requirement of the battery until the vehicle arrives at the destination. Then, the control unit 11 predicts the transition of the battery temperature rise when temperature control is not performed from the start of the vehicle's driving until it arrives at the destination based on the battery temperature and the heat generation amount of the battery 12 during driving due to charge / discharge, and predicts the temperature of the battery 12 when the vehicle arrives at the destination based on the prediction result.

[0026] Next, the control unit 11 determines whether the driving time of the vehicle exceeds a threshold value (S3). Whether the driving time of the vehicle exceeds the threshold value may be determined based on the driving time predicted from the driving route, or may be determined based on the driving distance predicted from the driving route.

[0027] Next, when the control unit 11 determines that the driving time of the vehicle exceeds the threshold value (S3: YES), in other words, when it determines that the driving time of the vehicle is a long-time driving, as the first battery temperature control, the temperature of the battery 12 is adjusted so that the temperature of the battery 12 falls within the optimal range (S4). That is, in step S4, a battery temperature management control for performing temperature management of the battery 12 within the optimal range is executed.

[0028] Also, when the control unit 11 determines that the driving time of the vehicle does not exceed the threshold value (S3: NO), in other words, when it determines that the driving time of the vehicle is a short-time driving, based on the prediction result of step S2, it is determined whether the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination (S5).

[0029] When the control unit 11 determines that the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination (S5: YES), as the second battery temperature control, the temperature of the battery 12 is adjusted so that the temperature of the battery 12 falls within the allowable range (S6). That is, in step S6, a battery temperature management control for performing temperature management of the battery 12 within the allowable range is executed.

[0030] When the control unit 11 determines that the temperature of the battery 12 does not exceed the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination (S5: NO), it stops the execution of the battery temperature management control under the target temperature and the temperature management range (S7). At this time, the control unit 11 may stop the operation of the circulation pump 14 to stop the circulation of the heat medium in the battery temperature control circuit 10. Further, the control unit 11 may simply circulate the heat medium in the battery temperature control circuit 10 without performing the temperature management of the battery under the target temperature and the temperature management range. For example, the heat medium that has not been cooled by the radiator or exchanged heat with the refrigerant may be circulated in the battery temperature control circuit 10. Thereby, the temperature unevenness between the battery cells of the battery 12 can be eliminated and the deterioration of the battery 12 can be prevented.

[0031] When the running time of the vehicle is the same as the threshold value, it may be determined as long-time running or short-time running.

[0032] As described above, by changing the battery temperature control when the battery 12 is used for a long time and when it is used for a short time, when the battery 12 is used for a long time, the temperature of the battery 12 is adjusted within the optimal range considering the deterioration of the battery 12, and when the battery 12 is used for a short time, the increase in power consumption caused by unnecessarily adjusting the temperature within the optimal range can be suppressed.

[0033] That is, by adjusting the temperature of the battery 12 within the optimal range during long-time running, the life of the battery 12 can be extended, and by adjusting the temperature of the battery 12 within the allowable range during short-time running, the increase in power consumption can be suppressed while suppressing the performance degradation of the battery 12.

[0034] The temperature control of the battery 12 may be performed in real time by monitoring the battery temperature during the running of the vehicle, or may be performed as pre-temperature control before the passengers board.

[0035] For example, the control unit 11 determines whether to execute pre-temperature control by determining whether an occupant is scheduled to board. Whether an occupant is scheduled to board can be determined, for example, from the activation of the vehicle system before the occupant boards by a remote control operation from outside the vehicle, the activation of the vehicle system before the occupant boards by a timer, learning data based on the behavior pattern of the vehicle owner, and the like.

[0036] Then, when an occupant is scheduled to board and the battery 12 is being externally charged, the control unit 11 executes pre-temperature control. The pre-temperature control can be executed in combination with pre-air conditioning for pre-cooling the vehicle interior.

[0037] In this case, when driving for a long time, the temperature of the battery 12 cannot be kept within the optimal range only by pre-temperature control. Therefore, in the battery temperature control in step S4 of FIG. 2, pre-temperature control is performed to bring the temperature of the battery 12 within the optimal range before the vehicle starts, or pre-temperature control is performed to bring the temperature of the battery 12 close to the optimal range before the vehicle starts, and when the temperature of the battery 12 exceeds the upper limit value of 30°C of the optimal range during vehicle driving, the battery 12 is cooled to control the temperature of the battery 12. For example, in pre-temperature control, the temperature of the battery 12 is controlled by cooling or heating the heat medium through heat exchange in the refrigerant circuit 16, and during vehicle driving, the battery 12 is cooled by cooling the heat medium by the radiator. At this time, the battery 12 is cooled so that the temperature of the battery 12 does not drop below the lower limit value of the optimal range. As a result, the temperature of the battery 12 is kept within the optimal range.

[0038] On the one hand, when driving for a short time, the temperature of the battery 12 can be kept within the allowable range by only pre-temperature control. Therefore, in the battery temperature control of step S6 in FIG. 2, if the temperature of the battery 12 is within the allowable range when the vehicle arrives at the destination without performing temperature control during driving by performing pre-temperature control, the battery 12 is cooled so that the temperature of the battery 12 becomes the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination by pre-temperature control. For example, in pre-temperature control, the heat medium is cooled by heat exchange in the refrigerant circuit 16. As a result, the temperature of the battery 12 is kept within the allowable range. In this case, since temperature control does not need to be performed during driving, the power consumption during driving can be reduced.

[0039] On the other hand, in the battery temperature control of step S6 in FIG. 2, if the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination even after performing pre-temperature control, the battery 12 is cooled as much as possible so as not to fall below the lower limit value of the allowable range. Then, when it is determined that the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range during driving of the vehicle, the battery 12 is temperature-controlled by cooling the battery 12. For example, in pre-temperature control, the heat medium is cooled by heat exchange in the refrigerant circuit 16, and during driving of the vehicle, the battery 12 is cooled by cooling the heat medium by the radiator. As a result, the temperature of the battery 12 is kept within the allowable range. In this case, by performing pre-temperature control, the power consumption during driving can be reduced.

[0040] Note that the control unit 11 predicts the power consumption required to keep the temperature of the battery 12 at 40°C or lower, which is the upper limit value of the allowable range, when the vehicle arrives at the destination, even if a passenger is scheduled to board and the battery 12 is not being externally charged. Then, when the value obtained by subtracting the driving power from the remaining battery level is greater than the power consumption required for temperature control of the battery 12, pre-temperature control is performed in the same manner as described above.

[0041] Further, when the value obtained by subtracting the running power from the remaining battery level is smaller than the power consumption required for temperature control of the battery 12, the control unit 11 gives a notification prompting charging to the occupant. For example, it is displayed on an information display terminal such as a smartphone. As a result, when external charging of the battery 12 is started, pre-temperature control is executed in the same manner as above.

[0042] On the other hand, when external charging of the battery 12 is not started, temperature control of the battery 12 is executed while the vehicle is running.

[0043] In this case, in the battery temperature control of step S4 in FIG. 2, when it is determined that the temperature of the battery 12 exceeds the upper limit value of 30°C of the optimal range while the vehicle is running, the battery 12 is temperature-controlled by cooling the battery 12. For example, the battery 12 is cooled by cooling the heat medium with a radiator. At this time, the battery 12 is cooled so that the temperature of the battery 12 does not drop below the lower limit value of the optimal range. As a result, the temperature of the battery 12 remains within the optimal range.

[0044] In the battery temperature control of step S6 in FIG. 2, when it is determined that the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range while the vehicle is running, the battery 12 is temperature-controlled by cooling the battery 12. For example, the battery 12 is cooled by cooling the heat medium with a radiator. At this time, the battery 12 is cooled so that the temperature of the battery 12 does not drop below the lower limit value of the allowable range. As a result, the temperature of the battery 12 remains within the allowable range.

[0045] Note that regardless of whether pre-temperature control is performed or not, in step S7 of FIG. 2, power consumption required for battery temperature control can be reduced by not performing battery temperature control.

[0046] As described above, battery temperature control can be performed either when pre-temperature control is performed or when temperature control is performed while the vehicle is running. However, when pre-temperature control is performed, the power consumption of the battery 12 during vehicle running can be suppressed, which is effective in extending the driving distance of the vehicle.

[0047] FIG. 3 is an explanatory diagram showing a specific example of the temperature change of the battery 12 when the battery temperature control shown in FIG. 2 is executed. In FIG. 3, the pre-temperature control and the in-travel temperature control are separated by the boarding of the passenger, and the short-time travel and the long-time travel are separated by the threshold value TH. Then, a specific example in which the pre-temperature control is not performed in the case of short-time travel and a specific example in which the pre-temperature control is performed in the case of long-time travel are shown. In FIG. 3, the optimal range of the battery temperature is 20°C to 30°C, and the allowable range of the battery temperature is 0°C to 40°C.

[0048] As shown in FIG. 3, when performing long-time travel (step S3 in FIG. 2: YES), the battery 12 is heated by pre-temperature control to keep the temperature a of the battery 12 within the optimal range. Then, when it is determined that the temperature of the battery 12 exceeds the upper limit value of 30°C during the travel of the vehicle, the battery 12 is cooled so that the temperature of the battery 12 does not fall below 20°C (step S4 in FIG. 2). Thereby, when performing long-time travel, the temperature a of the battery 12 falls within the optimal range of 20°C to 30°C.

[0049] When performing short-time travel (step S3 in FIG. 2: NO), the battery 12 is temperature-controlled by cooling the battery 12 when it is determined that the temperature exceeds the upper limit value of 40°C, which is the allowable range, during the travel of the vehicle without performing pre-temperature control (step S6 in FIG. 2). As a result, in this example, the temperature b of the battery 12 decreases. In this example, the battery 12 is cooled so that the temperature of the battery 12 does not exceed 40°C. Then, when the vehicle arrives at the destination, the temperature b of the battery 12 reaches near the upper limit value of 40°C. Thereby, when performing short-time travel, the temperature of the battery 12 falls within the allowable range of 0°C to 40°C.

[0050] <Battery Temperature Control of the Second Embodiment> In order to suppress the deterioration and performance degradation of the battery 12, it is necessary to manage the temperature of the battery 12 within an optimal range during vehicle operation. On the other hand, when the vehicle arrives at the destination, even if the temperature of the battery 12 is managed within an allowable range, there is little impact on the deterioration and performance of the battery 12. Therefore, when the temperature of the battery 12 is managed within the optimal range until the vehicle arrives at the destination, the vehicle arrives at the destination with surplus thermal energy compared to the case where it is managed within the allowable range when the vehicle arrives at the destination. In this case, since the thermal energy is not used after the vehicle arrives at the destination, the loss of thermal energy after the vehicle arrives at the destination increases. For this reason, it is preferable to perform battery temperature management for suppressing the consumed energy while managing the temperature of the battery 12 within the optimal range. Therefore, the control unit 11 is capable of executing the battery temperature control shown in FIG. 4.

[0051] FIG. 4 is a flowchart showing an example of the battery temperature control by the control unit 11.

[0052] As shown in FIG. 4, the control unit 11 acquires the driving information of the vehicle (S1). The driving information is, for example, the remaining battery level, battery temperature, outside air temperature, driving distance, and driving time. These pieces of information can be acquired based on the departure information, destination information, and route information obtained from learning data, settings for the navigation device 19, data acquired from the cloud, data by communication with other vehicles, data acquired from infrastructure facilities, etc.

[0053] Next, the control unit 11 predicts the transition of the battery temperature rise based on the driving information, and predicts the temperature of the battery 12 when the vehicle arrives at the destination based on the predicted transition of the battery temperature rise (S2). Specifically, the control unit 11 predicts the timing of the charge / discharge request of the battery until the vehicle arrives at the destination. Then, the control unit 11 predicts the transition of the battery temperature rise when temperature control is not performed from the start of vehicle operation until the vehicle arrives at the destination based on the battery temperature and the heat generation amount of the battery 12 during driving due to charge / discharge, and predicts the temperature of the battery 12 when the vehicle arrives at the destination based on the prediction result.

[0054] Next, based on the prediction result in step S2, the control unit 11 determines whether the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination (S3).

[0055] When the control unit 11 determines that the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination (S3: YES), in the first time period after the vehicle starts running, the temperature of the battery 12 is within the optimal range, and in the second time period after the first time period until the vehicle arrives at the destination, battery temperature control is executed to adjust the temperature of the battery 12 so that the temperature of the battery 12 is within the allowable range (S4). That is, in step S4, battery temperature management control is executed to manage the temperature of the battery 12 so that the temperature of the battery 12 is within the optimal range in the first time period and within the allowable range in the second time period.

[0056] Specifically, based on the predicted change in the temperature rise of the battery in step S2, the control unit 11 identifies the running time of the vehicle until it reaches the temperature rise starting point of the battery 12 when the temperature of the battery 12 rises from the upper limit value of 30°C of the optimal range during the running of the vehicle and reaches the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination.

[0057] Then, in the first time period after the vehicle starts running until the running time of the vehicle reaches the time of the temperature rise starting point, battery temperature control is executed so that the temperature of the battery 12 is within the first temperature range and the temperature of the battery at the temperature rise starting point reaches the upper limit value of 30°C of the optimal range. On the other hand, battery temperature control is not executed in the second time period after the first time period until the vehicle arrives at the destination. As a result, in the first time period, the temperature of the battery 12 is within the optimal range and the temperature of the battery at the temperature rise starting point reaches the upper limit value of 30°C of the optimal range, and in the second time period, the temperature of the battery 12 is within the allowable range and reaches the upper limit value of 40°C of the allowable range when arriving at the destination.

[0058] When the control unit 11 determines that the temperature of the battery 12 does not exceed the upper limit value of the allowable range when the vehicle arrives at the destination (S3: NO), it stops the execution of the battery temperature management control under the target temperature and the temperature management range (S5). As a result, in the second time period, the temperature of the battery 12 falls within the allowable range. At this time, the control unit 11 may stop the operation of the circulation pump 14 to stop the circulation of the heat medium in the battery temperature control circuit 10. Also, the control unit 11 may simply circulate the heat medium in the battery temperature control circuit 10 without performing battery temperature management under the target temperature and the temperature management range. For example, it may circulate a heat medium that has not been cooled by a radiator or heat-exchanged with a refrigerant in the battery temperature control circuit 10. Thereby, the temperature unevenness between the battery cells of the battery 12 can be eliminated and the deterioration of the battery 12 can be prevented.

[0059] As described above, by managing the temperature of the battery 12 so that it falls within the allowable range when the vehicle arrives at the destination, unnecessary temperature control of the battery 12 within a range that does not affect the deterioration and performance of the battery 12 is not performed, so that energy consumption can be suppressed.

[0060] In particular, since battery temperature control is not executed in the second time period, energy consumption can be effectively suppressed. In this embodiment, an example in which battery temperature control is not executed in the second time period is described, but battery temperature control may be executed in the second time period.

[0061] Note that the temperature control of the battery 12 in step S4 of FIG. 4 may be performed according to a temperature control plan created before the passengers board the vehicle, or the temperature of the battery 12 may be monitored during the running of the vehicle without creating a temperature control plan. In either case, the temperature control of the battery 12 is performed after specifying the running time of the vehicle that reaches the above-described rising starting point.

[0062] When creating a temperature control plan for the battery 12, for example, in the first time period, create a temperature control plan for the battery 12 such that the temperature of the battery 12 falls within the first temperature range and the temperature of the battery at the starting point of the increase reaches the upper limit value of 30°C in the optimal range. Then, perform temperature control of the battery 12 according to the created temperature control plan. As a result, in the first time period, the temperature of the battery 12 falls within the optimal range and the temperature of the battery at the starting point of the increase reaches the upper limit value of 30°C in the optimal range. In the second time period, even if temperature control of the battery 12 is not performed, the temperature of the battery 12 falls within the allowable range and reaches the upper limit value of 40°C in the allowable range when arriving at the destination. Note that when the timing of the charge / discharge requirement of the battery 12 changes, recreate the temperature control plan.

[0063] When not creating a temperature control plan for the battery 12, for example, while monitoring the temperature of the battery 12, perform temperature control of the battery 12 during the running of the vehicle such that the temperature of the battery 12 falls within the optimal range and the temperature of the battery 12 at the starting point of the increase reaches the upper limit value of 30°C in the optimal range in the first time period. Note that when pre-temperature control described later makes it unnecessary to perform temperature control during running, only monitor the temperature of the battery 12 in the first time period. As a result, in the first time period, the temperature of the battery 12 falls within the optimal range and the temperature of the battery at the starting point of the increase reaches the upper limit value of 30°C in the optimal range. In the second time period, even if temperature control of the battery 12 is not performed, the temperature of the battery 12 falls within the allowable range and reaches the upper limit value of 40°C in the allowable range when arriving at the destination.

[0064] In either case of creating a temperature control plan for the battery 12 and not creating a temperature control plan for the battery 12, the temperature control of the battery 12 may be performed in real time by monitoring the temperature of the battery 12 during the running of the vehicle, or may be performed as pre-temperature control before the passenger boards.

[0065] For example, the control unit 11 determines whether to perform pre-temperature control by determining whether an occupant is scheduled to board. Whether an occupant is scheduled to board can be determined, for example, from the activation of the vehicle system before the occupant boards by a remote control operation from outside the vehicle, the activation of the vehicle system before the occupant boards by a timer, learning data based on the behavior pattern of the vehicle owner, and the like.

[0066] Then, when an occupant is scheduled to board and the battery 12 is being externally charged, the control unit 11 performs pre-temperature control. The pre-temperature control can be executed in combination with pre-air conditioning that pre-conditions the vehicle interior.

[0067] In the battery temperature control of step S4 in FIG. 4, by performing pre-temperature control so that the temperature of the battery 12 falls within the optimal range, even if the temperature control of the battery 12 is not performed during the running of the vehicle, when the temperature of the battery 12 falls within the optimal range in the first time zone and then falls within the allowable range in the second time zone, pre-temperature control is performed so that the temperature of the battery 12 reaches the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination. For example, in pre-temperature control, the battery 12 is temperature-controlled by cooling or heating the heat medium by heat exchange in the refrigerant circuit 16. As a result, in the first time zone, the temperature of the battery 12 falls within the optimal range and reaches the upper limit value of 30°C of the optimal range at the rising starting point, and in the second time zone, even if the temperature control of the battery 12 is not performed, the temperature of the battery 12 falls within the allowable range and reaches the upper limit value of 40°C of the allowable range when arriving at the destination. In this case, since it is not necessary to perform temperature control during running, the power consumption during running can be reduced.

[0068] On one hand, in the battery temperature control of step S4 in FIG. 4, if pre-temperature control is performed so that the temperature of battery 12 falls within the optimal range, but the temperature of battery 12 does not fall within the allowable range in the second time period after falling within the optimal range in the first time period, pre-temperature control is performed so that the temperature of battery 12 becomes the lower limit value of 20°C of the optimal range. Further, in the first time period, when it is determined that the temperature of battery 12 exceeds the upper limit value of 30°C of the optimal range, the temperature of battery 12 is controlled by cooling battery 12. At this time, in the first time period, the temperature of battery 12 is controlled so as not to drop below the lower limit value of 20°C of the optimal range. At the same time, the temperature of battery 12 is controlled so that the temperature of battery 12 reaches the upper limit value of 30°C of the optimal range at the starting point of the temperature rise. For example, in pre-temperature control, the temperature of battery 12 is controlled by cooling or heating the heat medium through heat exchange in the refrigerant circuit 16, and during the running of the vehicle, battery 12 is cooled by cooling the heat medium by the radiator. As a result, in the first time period, the temperature of battery 12 falls within the optimal range and reaches the upper limit value of 30°C of the optimal range at the starting point of the temperature rise, and in the second time period, even if the temperature control of battery 12 is not performed, the temperature of battery 12 falls within the allowable range and reaches the upper limit value of 40°C of the allowable range when arriving at the destination. In this case, pre-temperature control can reduce the power consumption during running.

[0069] Note that even if a passenger is scheduled to board, when the external charging of battery 12 is not in progress, the control unit 11 predicts the power consumption required to keep the temperature of battery 12 below the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination. Then, when the value obtained by subtracting the running power from the remaining battery level is greater than the power consumption required for the temperature control of battery 12, pre-temperature control is performed in the same manner as above.

[0070] Also, when the value obtained by subtracting the running power from the remaining battery level is smaller than the power consumption required for the temperature control of battery 12, the control unit 11 gives a notification prompting the passenger to charge. For example, it is displayed on an information display terminal such as a smartphone. As a result, when the external charging of battery 12 is started, pre-temperature control is executed in the same manner as above.

[0071] On the one hand, when external charging of the battery 12 is not started, temperature control of the battery 12 is performed during vehicle travel.

[0072] In this case, in the battery temperature control of step S4 in FIG. 4, in the first time period, while monitoring the temperature of the battery 12 in real time, when it is determined that the temperature of the battery 12 exceeds the upper limit value of 30°C in the optimal range during vehicle travel, the battery 12 is cooled to perform temperature control of the battery 12. At this time, in the first time period, the temperature of the battery 12 is controlled so as not to drop below the lower limit value of 20°C in the optimal range. At the same time, the temperature of the battery 12 is controlled during vehicle travel so that the temperature of the battery 12 reaches the upper limit value of 30°C in the optimal range at the starting point of temperature rise. For example, the battery 12 is cooled by cooling the heat medium with a radiator. As a result, in the first time period, the temperature of the battery 12 is within the optimal range and reaches the upper limit value of 30°C in the optimal range at the starting point of temperature rise, and in the second time period, even if temperature control of the battery 12 is not performed, the temperature of the battery 12 is within the allowable range and reaches the upper limit value of 40°C in the allowable range when arriving at the destination.

[0073] Note that in step S5 in FIG. 4, power consumption required for battery temperature control can be reduced by not performing battery temperature control.

[0074] As described above, battery temperature control can be performed either when pre-temperature control is performed or when temperature control is performed during vehicle travel. However, when pre-temperature control is performed, the power consumption of the battery 12 during vehicle travel can be suppressed, which is effective in extending the driving distance of the vehicle.

[0075] FIG. 5 is an explanatory diagram showing a specific example of the temperature change of the battery 12 when the battery temperature control shown in FIG. 4 is executed. Note that FIG. 5 is a specific example when pre-temperature control is executed. In FIG. 5, the pre-temperature control start time before the passenger boards is set to 0, and the passenger's riding time is set to t1. Then, when the vehicle starts running from t1 and arrives at the destination at t2, the temperature of the battery 12 is defined as temperature a; when the vehicle starts running from t1 and arrives at the destination at t3, the temperature of the battery 12 is defined as temperature b; when the vehicle starts running from t1 and arrives at the destination at t4, the temperature of the battery 12 is defined as temperature c. In FIG. 5, the optimal range of the battery temperature is 20°C to 30°C, and the allowable range of the battery temperature is 0°C to 40°C.

[0076] As shown in FIG. 5, when the vehicle starts running from t1 and arrives at the destination at t2, it can be predicted that when the vehicle arrives at the destination, the temperature a of the battery 12 does not exceed the upper limit value of 40°C of the allowable range (step S3: NO in FIG. 4). And since the running time is short and the impact on the battery 12 is small, the temperature control of the battery 12 is not performed (step S5 in FIG. 4). In this case, the power consumption required for battery temperature control can be reduced.

[0077] On the other hand, when the vehicle starts running from t1 and arrives at the destination at t3, it can be predicted that when the vehicle arrives at the destination, the temperature b of the battery 12 exceeds the upper limit value of 40°C of the allowable range (step S3: YES in FIG. 4).

[0078] Therefore, based on the predicted transition of the temperature rise of the battery 12, when the temperature b of the battery 12 rises from the upper limit value of 30°C of the optimal range during the running of the vehicle and reaches the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination, the running time t11 of the vehicle until it reaches the temperature rise starting point s1 of the battery is specified.

[0079] Then, in the first time period t1 to t11 until the driving time of the vehicle reaches the rising starting point s1 at time t11, battery temperature control is executed so that the temperature of the battery 12 remains within the optimal range and the temperature b of the battery 12 at the rising starting point s1 reaches the upper limit value of 30°C in the optimal range (step S4 in FIG. 4).

[0080] On the other hand, battery temperature control is not executed in the second time period t11 to t3 from when the driving time of the vehicle reaches the rising starting point s1 at time t11 until the vehicle reaches the destination at time t3.

[0081] In this example, if pre-temperature control is performed so that the temperature of the battery 12 is within the optimal range before the passengers board the vehicle, then in the first time period t1 to t11, the temperature of the battery 12 remains within the optimal range and the temperature b of the battery 12 at the rising starting point s1 reaches the upper limit value of 30°C in the optimal range even without performing temperature control on the battery 12 during vehicle driving. Also, in the second time period t11 to t3, the temperature of the battery 12 reaches the upper limit value of 40°C within the allowable range when arriving at the destination even without performing temperature control on the battery 12. Therefore, in this example, only pre-temperature control is performed to cool the battery 12 so that the temperature of the battery 12 is within the optimal range before the passengers board the vehicle. In this way, by performing pre-temperature control, the need for temperature control during driving is eliminated, so the power consumption during driving can be reduced.

[0082] Also, when the vehicle starts driving from t1 and arrives at the destination at t4, based on the transition of the temperature rise of the battery 12, it can be predicted that the temperature c of the battery 12 will exceed the upper limit value of 40°C within the allowable range when the vehicle arrives at the destination (step S3 in FIG. 4: YES).

[0083] Therefore, based on the predicted transition of the temperature rise of the battery 12, the driving time t22 of the vehicle until it reaches the rising starting point s2 of the battery temperature during vehicle driving when the temperature c of the battery 12 rises from the upper limit value of 30°C in the optimal range during vehicle driving and reaches the upper limit value of 40°C within the allowable range when the vehicle arrives at the destination is specified.

[0084] Then, in the first time period t1 to t22 until the driving time of the vehicle reaches the rising starting point s2, i.e., the time t22, battery temperature control is executed so that the temperature of the battery 12 remains within the optimal range and the temperature c of the battery 12 at the rising starting point s2 reaches the upper limit value of 30°C of the optimal range (step S4 in FIG. 4).

[0085] On the other hand, battery temperature control is not executed in the second time period t22 to t4 from when the driving time of the vehicle reaches the time t22 at the rising starting point s2 until the time t4 when the vehicle arrives at the destination.

[0086] In this example, even if pre-temperature control for cooling the battery 12 is performed before the passengers board the vehicle, the temperature of the battery 12 exceeds the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination. Therefore, in this example, pre-temperature control is performed so that the temperature of the battery 12 drops to 20°C, which is the lower limit value of the optimal range, before the passengers board the vehicle, and temperature control of the battery 12 is performed while the vehicle is running. As a result, in the first time period t1 to t22, the temperature of the battery 12 remains within the optimal range and the temperature c of the battery 12 at the rising starting point s2 reaches the upper limit value of 30°C of the optimal range. Also, in the second time period t22 to t4, the temperature of the battery 12 reaches the upper limit value of 40°C of the allowable range when the vehicle arrives at the destination even without performing temperature control of the battery 12. Thereby, the power consumption during running can be reduced compared to the case where temperature control is performed only during running.

[0087] In addition, in this embodiment, an example in which battery temperature control is executed so that the temperature of the battery 12 reaches the upper limit value of the allowable range when the vehicle arrives at the destination has been described. However, if the temperature of the battery 12 remains within the allowable range when the vehicle arrives at the destination, it is not always necessary to execute battery temperature control so that the temperature reaches the upper limit value. That is, when heating of the battery 12 is required so that the temperature of the battery 12 reaches the upper limit value of the allowable range, it is preferable to perform temperature control within the allowable range without heating the battery 12. Thereby, an increase in energy consumption can be suppressed.

[0088] [Effects of this Embodiment] (a1) A vehicle battery temperature control system 1 includes a battery 12 mounted on a vehicle, a battery temperature control unit for temperature control of the battery 12, and a control unit 11 capable of executing battery temperature control for controlling the temperature control of the battery. The control unit 11 predicts the driving information of the vehicle from the departure of the vehicle from the current location until it arrives at the destination, determines whether the driving time of the vehicle exceeds a threshold value based on the predicted driving information, executes first battery temperature control when it is determined that the driving time of the vehicle exceeds the threshold value, and executes second battery temperature control when it is determined that the driving time of the vehicle does not exceed the threshold value. Therefore, by changing the battery temperature control when the battery 12 is used for a long time and when it is used for a short time, when the battery 12 is used for a long time, the temperature control of the battery 12 is performed within an optimal range considering the deterioration of the battery 12, and when the battery 12 is used for a short time, an increase in power consumption caused by unnecessarily performing temperature control within the optimal range can be suppressed.

[0089] Note that, as an example of the first battery temperature control, the temperature control of the battery is performed so that the temperature of the battery falls within the optimal range, and as an example of the second battery temperature control, the example where the temperature of the battery falls within the allowable range is given for explanation. However, for example, in the first battery temperature control, the ratio of the temperature of the battery falling within the optimal range is made higher than that in the second battery temperature control. The modes of the first battery temperature control and the second battery temperature control are not limited to the modes of this embodiment.

[0090] (a2) In the first battery temperature control, the control unit 11 performs temperature control of the battery so that the temperature of the battery falls within the optimal range which is the first temperature range. In the second battery temperature control, the control unit 11 performs temperature control of the battery so that the temperature of the battery falls within the allowable range which is the second temperature range wider than the first temperature range. Performing temperature control of the battery so that it falls within the optimal range which is the first temperature range has less impact on the deterioration or performance of the battery than performing temperature control of the battery so that it falls within the allowable range which is the second temperature range. Therefore, when the battery 12 is used for a long time, temperature control of the battery 12 is performed within an optimal range considering the deterioration of the battery 12, and when the battery 12 is used for a short time, an increase in power consumption caused by unnecessarily performing temperature control within the optimal range can be suppressed.

[0091] (a3) In the second battery temperature control, the control unit 11 determines whether the temperature of the battery 12 exceeds the upper limit value of 40°C, which is the allowable range within the second temperature range. When it is determined that the temperature of the battery 12 exceeds the upper limit value of 40°C within the second temperature range, the battery temperature control is executed. Therefore, when the battery 12 is used for a short time, by performing temperature control of the battery 12 so as to reach the upper limit value of 40°C within the allowable range, it is possible to suppress an increase in power consumption while suppressing deterioration of the battery 12.

[0092] (b1) A vehicle battery temperature control system 1 includes a battery 12 mounted on a vehicle, a battery temperature control unit that controls the temperature of the battery 12, and a control unit 11 capable of executing battery temperature control for controlling the temperature of the battery. The control unit 11 performs battery temperature control so that the temperature of the battery falls within an optimal range within the first temperature range during a first time period after the vehicle starts running, and within an allowable range within a second temperature range that is wider than the optimal range within the first temperature range during a second time period after the first time period until the vehicle reaches the destination. Therefore, by managing the temperature of the battery 12 so that it falls within the allowable range when the vehicle reaches the destination, unnecessary temperature control of the battery 12 within a range that does not affect the deterioration or performance of the battery 12 is eliminated, and energy consumption can be suppressed.

[0093] (b2) The control unit 11 executes battery temperature control so that the temperature of the battery 12 reaches the upper limit value of 40°C, which is the allowable range within the second temperature range, so that the temperature of the battery 12 falls within the second temperature range when the vehicle reaches the destination. Therefore, by controlling the temperature of the battery 12 so that it reaches the upper limit value of 40°C within the allowable range when the vehicle arrives at the destination, unnecessary temperature control of the battery 12 within the range that does not affect the deterioration and performance of the temperature-controlled battery 12 is eliminated, and thus energy consumption can be suppressed.

[0094] (b3) The control unit 11 predicts the rising trend of the temperature of the battery 12 from when the vehicle starts running until it arrives at the destination, and based on the predicted rising trend, determines whether the temperature of the battery 12 exceeds the upper limit value of 40°C, which is the upper limit of the allowable range in the second temperature range, when the temperature of the battery 12 rises from when the vehicle starts running until it arrives at the destination. If the temperature of the battery 12 exceeds the upper limit value of 40°C, which is the upper limit of the allowable range in the second temperature range, the control unit 11 identifies the running time of the vehicle until it reaches the starting point of the temperature rise of the battery 12 in the case where the temperature of the battery 12 rises from the upper limit value of 30°C, which is the upper limit of the optimal range in the first temperature range, during the running of the vehicle and reaches the upper limit value of 40°C, which is the upper limit of the allowable range in the second temperature range, when the vehicle arrives at the destination, based on the predicted rising trend. In the first time period, which is the time period after the vehicle starts running and until the running time of the vehicle reaches the time to reach the starting point of the temperature rise, the battery temperature control is executed so that the temperature of the battery 12 is within the optimal range in the first temperature range and the temperature of the battery at the starting point of the temperature rise reaches the upper limit value of 30°C, which is the upper limit of the optimal range in the first temperature range. In the second time period, which is the time period after the first time period and until the vehicle arrives at the destination, the battery temperature control is not executed. Therefore, by not performing temperature control of the battery 12 in the second time period, it becomes possible to reduce the power required for temperature control of the battery 12, and thus energy consumption can be suppressed.

[0095] As described above, the present invention has been described by showing preferred embodiments. However, it goes without saying that the present invention is not limited only to the above-described embodiments, and various modifications can be made within the scope of the present invention.

Explanation of Reference Numerals

[0096] 1: Vehicle battery temperature control system 10: Battery temperature control circuit 11: Control unit 12: Battery 13: Battery temperature control section 14: Circulation pump 15: Heat medium heating device 16: Refrigerant circuit

Claims

1. A vehicle battery temperature control system comprising a battery mounted on a vehicle, a battery temperature control unit for temperature control of the battery, and a control unit capable of executing battery temperature control for controlling the temperature control of the battery, wherein the control unit predicts the driving information of the vehicle from the time the vehicle departs from the current location until it arrives at the destination, determines whether the driving time of the vehicle exceeds a threshold based on the predicted driving information, executes first battery temperature control when it is determined that the driving time of the vehicle exceeds the threshold, and executes second battery temperature control when it is determined that the driving time of the vehicle does not exceed the threshold A vehicle battery temperature control system characterized by the above.

2. In the first battery temperature control, the control unit performs temperature control of the battery so that the temperature of the battery falls within a first temperature range. In the second battery temperature control, the control unit performs temperature control of the battery so that the temperature of the battery falls within a second temperature range that is wider than the first temperature range. Controlling the temperature of the battery so that it falls within the first temperature range has less impact on the degradation or performance of the battery than controlling the temperature of the battery so that it falls within the second temperature range. The vehicle battery temperature control system according to claim 1, characterized by the above.

3. In the second battery temperature control, the control unit determines whether the temperature of the battery exceeds the upper limit value of the second temperature range, and executes battery temperature control when it is determined that the temperature of the battery exceeds the upper limit value of the second temperature range. The vehicle battery temperature control system according to claim 2, characterized by the above.

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