US-20260128403-A1 - BATTERY COOLING SYSTEM FOR VEHICLE AND CONTROL METHOD THEREOF

Abstract

A battery cooling system for a vehicle and a control method are disclosed. The control method for the battery cooling system may include receiving a detected ambient temperature and obtaining a battery cooling level, determining a switching state control condition based on the ambient temperature and the battery cooling level, determining a first activating temperature and a second activating temperature based on a set temperature of the air conditioning system, controlling a switching status of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, receiving an evaporation temperature and comparing the received evaporation temperature with the determined first activating temperature, controlling the battery chiller expansion valve to open when the evaporation temperature is less than or equal to the second activating temperature, and controlling the battery chiller expansion valve to close when the evaporation temperature is greater than the second activating temperature.

Inventors

• Qing Dong HOU
• Tae Hun Jung
• Xiaorui Zhai

Assignees

• HYUNDAI MOTOR COMPANY
• KIA CORPORATION

Dates

Publication Date

20260507

Application Date

20251105

Priority Date

20241105

Claims (20)

1. 1 . A battery cooling system for a vehicle, comprising: an ambient temperature sensor configured to detect an ambient temperature; an evaporator temperature sensor configured to detect an evaporator temperature of an air conditioning system; a battery chiller configured to cool a coolant supplied from the battery cooling system through heat exchange between a refrigerant supplied from the air conditioning system and the coolant, and cool a battery using the cooled coolant; a battery chiller expansion valve provided upstream of the battery chiller and configured to selectively introduce the refrigerant into the battery chiller in an expanded state; and a controller comprising a memory storing computer-executable instructions, and at least one processor configured to access the memory and execute the instructions, wherein the instructions comprise: receiving the ambient temperature detected from the ambient temperature sensor; obtaining a battery cooling level; determining a switching state control condition for dynamically controlling a switching state of the battery chiller expansion valve based on the ambient temperature and the battery cooling level; determining a first activating temperature and a second activating temperature for controlling activation of the battery chiller expansion valve based on a set temperature received from an air conditioning system, and controlling the switching state of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, wherein the second activating temperature is less than the first activating temperature; receiving the evaporator temperature from the evaporator temperature sensor and comparing the evaporator temperature to the second activating temperature; and controlling the battery chiller expansion valve to an open state when the evaporator temperature is less than or equal to the second activating temperature; and controlling the battery chiller expansion valve to a closed state when the evaporator temperature is greater than the second activating temperature.
2. 2 . The battery cooling system of claim 1 , wherein the instructions further comprise: determining the switching state control condition for dynamically controlling the switching state of the battery chiller expansion valve when the ambient temperature is greater than or equal to a first predetermined temperature, and the battery cooling level is greater than or equal to a first or lowermost battery cooling level and less than a second or uppermost battery cooling level.
3. 3 . The battery cooling system of claim 1 , wherein the instructions further comprise: determining an elapsed time since the battery chiller expansion valve is closed; comparing the elapsed time to a first predetermined time; receiving the evaporator temperature from the evaporator temperature sensor when the elapsed time is less than the first predetermined time, and comparing the evaporator temperature to the second activating temperature; opening the battery chiller expansion valve when the evaporator temperature is less than or equal to the second activating temperature; and re-determining the elapsed time since the battery chiller expansion valve is closed, and comparing the re-determined elapsed time to the first predetermined time when the evaporator temperature is greater than the second activating temperature.
4. 4 . The battery cooling system of claim 3 , wherein the instructions further comprise: determining a first increased first activating temperature and a first increased second activating temperature by increasing the first activating temperature and the second activating temperature by a first predetermined value, when the elapsed time since the battery chiller expansion valve is closed is greater than or equal to the first predetermined time.
5. 5 . The battery cooling system of claim 4 , wherein the instructions further comprise: receiving the evaporator temperature from the evaporator temperature sensor after increasing the first activating temperature and the second activating temperature by the first predetermined value, and comparing the evaporator temperature to the first increased second activating temperature; and opening the battery chiller expansion valve when the evaporator temperature is less than or equal to the first increased second activating temperature.
6. 6 . The battery cooling system of claim 5 , wherein the instructions further comprise: determining an elapsed time, since the first activating temperature and the second activating temperature are adjusted; comparing the elapsed time, since the first activating temperature and the second activating temperature are adjusted, to a second predetermined time; and increasing the first increased first activating temperature to a second increased first activating temperature and increasing the second increased activating temperature to a second increased second activating temperature by a second predetermined value when the elapsed time, since the first activating temperature and the second activating temperature are adjusted, is greater than or equal to the second predetermined time.
7. 7 . The battery cooling system of claim 6 , wherein the instructions further comprise: receiving the evaporator temperature from the evaporator temperature sensor after increasing the first increased first activating temperature and increasing the first increased second activating temperature by the second predetermined value, and comparing the evaporator temperature to the second increased second activating temperature; opening the battery chiller expansion valve when the evaporator temperature is less than or equal to the second increased second activating temperature; and determining an elapsed time, since the first increased first activating temperature and the first increased second activating temperature are adjusted, and comparing the elapsed time to the second predetermined time when the evaporator temperature is greater than the second increased second activating temperature.
8. 8 . The battery cooling system of claim 7 , wherein the instructions further comprise: increasing the second increased first activating temperature to a third increased first activating temperature and increasing the second increased second activating temperature by a second predetermined value to a third increased second activating temperature when the elapsed time, since the first increased first activating temperature and the first increased second activating temperature are adjusted, is greater than or equal to the second predetermined time.
9. 9 . The battery cooling system of claim 1 , wherein the instructions further comprise: determining an elapsed time, since the battery chiller expansion valve is open, and comparing the elapsed time since the battery chiller expansion valve to a first predetermined time; receiving the evaporator temperature from the evaporator temperature sensor when the elapsed time since the battery chiller expansion valve is open is less than the first predetermined time, and determining the evaporator temperature and comparing the evaporator temperature to the first activating temperature; closing the battery chiller expansion valve when the evaporator temperature is greater than or equal to the first activating temperature; and re-determining the elapsed time since the battery chiller expansion valve is open and comparing the re-determined elapsed time to the first predetermined time when the evaporator temperature is less than the first activating temperature.
10. 10 . The battery cooling system of claim 9 , wherein instructions further comprise: determining a first decreased first activating temperature by decreasing the first activating temperature and a first decreased second activating temperature by decreasing the second activating temperature by a first predetermined value when the elapsed time, since the battery chiller expansion valve is open, is greater than or equal to the first predetermined time.
11. 11 . The battery cooling system of claim 10 , wherein instructions further comprise: receiving the evaporator temperature from the evaporator temperature sensor after decreasing the first activating temperature and decreasing the second activating temperature by the first predetermined value, and comparing the evaporator temperature to the first decreased first activating temperature; and closing the battery chiller expansion valve when the evaporator temperature is greater than or equal to the first decreased first activating temperature.
12. 12 . The battery cooling system of claim 11 , wherein instructions further comprise: comparing an elapsed time, since the first activating temperature and the second activating temperature are adjusted, to a second predetermined time when the evaporator temperature is less than the first decreased first activating temperature; and decreasing the first decreased first activating temperature to a second decreased first activating temperature and decreasing the first decreased second activating temperature by a second predetermined value to a second decreased second activating temperature when the elapsed time, since the first activating temperature and the second activating temperature are adjusted, is greater than or equal to the second predetermined time.
13. 13 . The battery cooling system of claim 12 , wherein instructions further comprise: receiving the evaporator temperature from the evaporator temperature sensor after decreasing the first decreased first activating temperature and the first decreased second activating temperature by the second predetermined value, and determining the evaporator temperature and comparing the evaporator temperature to the second decreased first activating temperature; closing the battery chiller expansion valve when the evaporator temperature is greater than or equal to the second decreased first activating temperature; and determining an elapsed time since the first decreased first activating temperature and the first decreased second activating temperature are adjusted and comparing the elapsed time since the first decreased first activating temperature and the first decreased second activating temperature are adjusted to the second predetermined time when the evaporator temperature is less than the second decreased first activating temperature.
14. 14 . The battery cooling system of claim 13 , wherein instructions further comprise: decreasing the second decreased first activating temperature to a third decreased first activating temperature and the second decreased second activating temperature to a third decreased second activating temperature by the second predetermined value when the elapsed time since the first decreased first activating temperature and the first decreased second activating temperature are adjusted is greater than or equal to the second predetermined time.
15. 15 . The battery cooling system of claim 1 , wherein the instructions, while controlling a switching status of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, further comprise: stopping the switching state of the battery chiller expansion valve according to the first activating temperature and the second activating temperature based on the switching state control condition; or determining the first activating temperature and the second activating temperature according to a changed set temperature of the air conditioning system when the set temperature is changed.
16. 16 . A control method for a battery cooling system for a vehicle, the control method comprising: via a controller, receiving an ambient temperature detected from an ambient temperature sensor; obtaining a battery cooling level; determining a switching state control condition for dynamically controlling a switching state of a battery chiller expansion valve based on the ambient temperature and the battery cooling level; determining a first activating temperature and a second activating temperature for controlling activation of the battery chiller expansion valve based on a set temperature received from an air conditioning system based on the switching state control condition, and controlling the switching state of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, wherein the second activating temperature is less than the first activating temperature; receiving an evaporator temperature from an evaporator temperature sensor and comparing the evaporator temperature to the second activating temperature; opening the battery chiller expansion valve to an open state when the evaporator temperature is less than or equal to the second activating temperature; and closing the battery chiller expansion valve to a closed state when the evaporator temperature is greater than the second activating temperature.
17. 17 . The control method of claim 16 , wherein determining the switching state control condition comprises: determining the switching state control condition for dynamically controlling the switching state of the battery chiller expansion valve when the ambient temperature is greater than or equal to a first predetermined temperature, and the battery cooling level is greater than or equal to a lowermost battery cooling level and less than an uppermost battery cooling level.
18. 18 . The control method of claim 16 , wherein, after the battery chiller expansion valve is closed, by the controller, the method comprises: determining an elapsed time since the battery chiller expansion valve is closed and comparing the elapsed time since the battery chiller expansion valve is closed to a first predetermined time; receiving the evaporator temperature from the evaporator temperature sensor when the elapsed time since the battery chiller expansion valve is closed is less than the first predetermined time, and determining the evaporator temperature and comparing the evaporator temperature to the second activating temperature; opening the battery chiller expansion valve when the evaporator temperature is less than or equal to the second activating temperature; and re-determining the elapsed time since the battery chiller expansion valve is closed, and comparing the elapsed time since the battery chiller expansion valve is closed to the first predetermined time when the evaporator temperature is greater than the second activating temperature.
19. 19 . The control method of claim 16 , wherein, after the battery chiller expansion valve is open, by the controller, the method comprises: determining an elapsed time since the battery chiller expansion valve is open and comparing the elapsed time since the battery chiller expansion valve is open to a first predetermined time; receiving the evaporator temperature from the evaporator temperature sensor when the elapsed time since the battery chiller expansion valve is open is less than the first predetermined time, and determining the evaporator temperature and comparing the evaporator temperature to the first activating temperature; closing the battery chiller expansion valve when the evaporator temperature is greater than or equal to the first activating temperature; and re-determining the elapsed time, since the battery chiller expansion valve is open, and comparing the elapsed time since the battery chiller expansion valve is open to the first predetermined time when the evaporator temperature is less than the first activating temperature.
20. 20 . The control method of claim 16 , while controlling a switching status of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, the method further comprising: stopping the switching state of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, by the controller, based on the switching state control condition; or determining the first activating temperature and the second activating temperature according to a changed set temperature of the air conditioning system when the set temperature is changed.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims priority to and the benefit of Chinese Patent Application No. 202411564239.1 filed with the Chinese National Intellectual Property Administration on Nov. 5, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD The present disclosure relates to a battery cooling system for a vehicle and a control method therefor, capable of dynamically controlling a switching state of the battery chiller expansion valve of the battery cooling system according to an activating state of an air conditioning system for the vehicle. BACKGROUND An electric vehicle has a high-voltage battery installed as a power source. The battery cooling system of the electric vehicle is equipped with a battery chiller to maintain a high-voltage battery temperature at an (e.g., optimal) activating level. By installing the battery chiller of the battery cooling system and an evaporator of an air conditioning system in parallel, the battery chiller may (e.g., is able to) cool a coolant of the battery cooling system by exchanging heat between the coolant and a refrigerant supplied from an air conditioning device, thereby allowing the cooled coolant to cool the high-voltage battery. An expansion valve may be installed upstream of the battery chiller to expand the refrigerant. Recently, with the development of electric vehicles, energy density and charging speed of high-voltage batteries are gradually increasing, and a demand for cooling of high-voltage batteries is also increasing. As the cooling demand of high-voltage batteries increases, the size of battery chillers is also increasing, and opening the expansion valve installed upstream of the battery chiller may impact the performance of the air conditioning system. If an opening degree of the expansion valve is large, a large amount of refrigerant flows from the air conditioning system to the battery chiller of the battery cooling system, reducing a cooling effect of the air conditioning system. If the opening degree of the expansion valve is small and a temperature at an outlet of the battery chiller is high, and, at the same time, a coolant temperature at an inlet of the battery chiller is high, the battery cooling effect may be reduced and may cause the air conditioning system to overheat, thereby reducing the cooling efficiency. Accordingly, a conventional battery cooling system and a control method therefor may not be able to accommodate the cooling demand of current high-voltage batteries. The above information disclosed in this Background section is for enhancement of understanding of the background of the disclosure, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. SUMMARY An example embodiment of the present disclosure provides a battery cooling system for a vehicle and a method for controlling the same. An example embodiment of the present disclosure provides a battery cooling system for a vehicle. The system may include an ambient temperature sensor, an evaporator temperature sensor, a battery chiller, a battery chiller expansion valve, and a controller. The ambient temperature sensor may be configured to detect an ambient temperature. The evaporator temperature sensor may be configured to detect an evaporator temperature of an air conditioning system. The battery chiller may be configured to cool a coolant supplied from the battery cooling system through heat exchange between a refrigerant supplied from the air conditioning system and the coolant, and cool a battery using the cooled coolant, and the battery chiller expansion valve may be provided upstream of the battery chiller and configured to selectively introduce the refrigerant into the battery chiller in an expanded state. The controller may be configured to receive the ambient temperature detected from the ambient temperature sensor, to obtain a battery cooling level, and to determine whether the switching state control condition for dynamically controlling a switching state of the battery chiller expansion valve is satisfied based on the ambient temperature and the battery cooling level. The controller further may be configured, to determine a first activating temperature and a second activating temperature for controlling activation of the battery chiller expansion valve based on a set temperature received from an air conditioning system upon determining that the switching state control condition is satisfied, and control the switching state of the battery chiller expansion valve according to the first activating temperature and the second activating temperature, wherein the second activating temperature is lower than the first activating temperature. Also, the controller may be configured to receive the evaporator temperature from the evaporator temperature sensor and determine whether the evaporator temperature is lower