A vehicle battery cooling device and control method

Abstract

This application relates to a vehicle battery cooling device and control method. The device includes a battery pack cooling module, an acquisition module, a calculation module, and an adjustment module. The acquisition module is used to acquire the average heat generation power and average temperature of the battery pack. The calculation module is used to determine the target cooling power of the cooling unit based on the average heat generation power when the average heat generation power is greater than a heat generation power threshold and the average temperature of the battery pack is greater than a cooling temperature threshold. The adjustment module is used to adjust the actual cooling power to the target cooling power to balance the heat generation of the battery pack. By using the cooling device and control method provided in this application, the problem of battery cooling lag in the prior art is improved.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle battery management technology, and in particular to a vehicle battery cooling device and control method. Background Technology

[0002] The battery pack is one of the core components of new energy vehicles, directly affecting their range. The temperature of the battery pack is a direct factor affecting its performance, making thermal management of the battery pack particularly important.

[0003] Existing battery thermal management systems typically cool the battery based on the battery pack temperature. Cooling is activated when the battery pack temperature reaches the upper limit of the control range, and the cooling power is usually determined based on the battery pack temperature. That is, the cooling power will only increase as the battery pack temperature rises further, thus resulting in a certain cooling lag. Summary of the Invention

[0004] Based on this, a vehicle battery cooling device and control method are provided to improve the problem of battery cooling lag in the prior art.

[0005] On one hand, a vehicle battery cooling device is provided, the device comprising:

[0006] A battery pack cooling module includes a refrigerant circuit and a cooling unit connected to the refrigerant circuit. The refrigerant circuit includes a compressor, a condenser, and an expansion valve connected in sequence. The cooling unit is connected to the battery pack to provide cooling power to the battery pack.

[0007] The acquisition module is used to acquire the average heat generation power and average temperature of the battery pack.

[0008] The calculation module is used to determine the target cooling power of the cooling unit based on the average heat generation power when the average heat generation power is greater than the heat generation power threshold and the average temperature of the battery pack is greater than the cooling temperature threshold.

[0009] An adjustment module is used to adjust the actual cooling power of the cooling unit to the target cooling power in order to balance the heat generation of the battery pack.

[0010] In one embodiment, the cooling unit includes a battery circuit, which includes a battery cooler, a medium pump, and a cooling assembly connected in sequence, and the cooling assembly is connected to the battery pack.

[0011] In one embodiment, the acquisition module is further configured to acquire the actual cooling power of the cooling unit. The acquisition module also includes a first temperature sensor, a second temperature sensor, and a flow sensing unit. The first temperature sensor is disposed at the medium outlet of the cooling component, the second temperature sensor is disposed at the medium inlet of the cooling component, and the flow sensing unit is configured to sense the medium flow rate of the battery circuit.

[0012] A vehicle battery cooling control method is also provided, including:

[0013] Obtain the average heat generation power and average temperature of the battery pack;

[0014] When the average heat generation power is greater than the heat generation power threshold and the average temperature of the battery pack is greater than the cooling temperature threshold, the target cooling power of the cooling unit is determined based on the average heat generation power, and the actual cooling power of the cooling unit is adjusted to the target cooling power to balance the heat generation of the battery pack.

[0015] In one embodiment, obtaining the average heat generation power and average temperature of the battery pack then includes:

[0016] The cooling temperature threshold is determined based on state parameters, including battery pack charge, average battery pack temperature, and ambient temperature. The cooling temperature threshold is negatively correlated with the battery pack charge, average battery pack temperature, and ambient temperature.

[0017] In one embodiment, the cooling temperature threshold is determined according to the following mathematical expression:

[0018] Thd1=f(SOC)×K1+f(BatTemp Avg )×K2+f(Temp Amb )×K3

[0019] Where Thd1 is the cooling temperature threshold, f(SOC) is the first parameter with the battery pack SOC as input, and f(BatTemp) is the first parameter with the battery pack SOC as input. Avg (Based on the average temperature of the battery pack, BatTemp) Avg The second parameter is f(Temp) as input. Amb (Based on ambient temperature) Amb K1, K2, and K3 are the third input parameter, and K1, K2, and K3 are the first, second, and third coefficients, respectively.

[0020] In one embodiment, obtaining the average heat dissipation power of the battery pack includes:

[0021] The discharge current and internal resistance of the battery pack are obtained, the instantaneous heating power is obtained based on the discharge current and the internal resistance, and the average heat dissipation power is obtained by averaging the instantaneous heating power over a fixed time period. The internal resistance is determined based on the battery pack charge, the average temperature of the battery pack, and the voltage of the individual battery cells.

[0022] In one embodiment, adjusting the actual cooling power to the target cooling power includes:

[0023] The actual cooling power is determined based on the following mathematical expression:

[0024] P c = (Tout - Tin) × L × C

[0025] Among them, P c The actual cooling power is Tout, the temperature of the cooling medium flowing out of the battery pack is Tin, the temperature of the cooling medium flowing into the battery pack is L, the medium flow rate is C, and the specific heat capacity of the medium is C.

[0026] In one embodiment, the target cooling power is determined according to the following mathematical expression:

[0027] P tag =P1×K4

[0028] Among them, P tag P1 is the target cooling power, P1 is the average heat generation power, and K4 is the fourth coefficient.

[0029] In one embodiment, adjusting the actual cooling power of the cooling unit to the target cooling power includes:

[0030] The target speed of the compressor is determined based on the average heat generation power, and the compressor is controlled based on the target speed to balance the heat generation of the battery; and / or,

[0031] The target opening degree of the expansion valve is determined based on the average heat generation power, and the expansion valve is controlled based on the target opening degree to balance the heat generation of the battery.

[0032] The aforementioned vehicle battery cooling device and control method determine whether the battery pack has a further tendency to heat up by jointly judging the average heat generation power and the average temperature of the battery pack. When both conditions are met, the target cooling power required for cooling is determined based on the average heat generation power. Before the battery pack temperature rises further, the heat generation is offset by power balance, which improves the problem of battery cooling lag and avoids the limitation of power performance caused by the rise in battery pack temperature. Attached Figure Description

[0033] Figure 1This is a structural block diagram of a vehicle battery cooling device in one embodiment;

[0034] Figure 2 This is a structural block diagram of the refrigerant circuit and battery circuit in one embodiment;

[0035] Figure 3 This is a flowchart illustrating a vehicle battery cooling device control method in one embodiment;

[0036] Figure 4 This is a flowchart illustrating a vehicle battery cooling device control method in another embodiment.

[0037] Figure description: Compressor 101, condenser 102, expansion valve 103, battery cooler 104, medium pump 105, cooling assembly 106, first temperature sensor 107, second temperature sensor 108. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0039] As a core component of new energy vehicles, the performance of the battery pack directly affects the vehicle's range and safety. Battery pack thermal management is a key technology to ensure the performance, safety, and lifespan of the power battery in a vehicle. The main functions of the thermal management system include battery cooling, which effectively dissipates heat when the vehicle battery experiences excessively high temperatures, preventing combustion accidents related to thermal runaway.

[0040] Currently, liquid cooling is the mainstream battery pack cooling method. It introduces cooling energy by connecting to the vehicle's refrigerant circuit, offering advantages such as good cooling effect and high economy. The cooling system can determine whether to turn on or off based on the battery temperature, and further adjust the cooling capacity according to the battery pack temperature. However, due to the lag in system adjustment, the battery pack temperature may still rise, affecting the vehicle's power performance.

[0041] This application provides a vehicle battery cooling device, such as... Figure 1 It includes a battery pack cooling module, an acquisition module, a calculation module, and an adjustment module. The battery pack cooling module includes a refrigerant circuit and a cooling unit connected to the refrigerant circuit, such as... Figure 2As shown, a circuit structure diagram of a battery pack cooling module is provided. The refrigerant circuit includes a compressor 101, a condenser 102, and an expansion valve 103 connected in sequence. It can be understood that the refrigerant circuit can also be used for refrigeration of the passenger compartment. For example, the evaporator connected to the refrigerant circuit can provide cooling capacity to the passenger compartment. The cooling unit is connected to the battery pack to provide cooling power to the battery pack.

[0042] The cooling process of the battery pack cooling module is illustrated by way of example. The refrigerant in its refrigerant circuit condenses into a liquid state at the condenser 102 under the action of the compressor 101. After passing through the expansion valve 103, it absorbs heat at the cooling unit, then reverts to a gaseous state and re-enters the compressor 101 to complete the cycle. The efficiency of heat absorption at the cooling unit is affected by the speed of the compressor 101 and the opening degree of the expansion valve 103.

[0043] The acquisition module is used to acquire the average heat generation power and average temperature of the battery pack. For example, the acquisition module determines the average heat generation power corresponding to a certain time scale by acquiring the total heat generation of the battery pack within a certain time period. On the other hand, the average temperature of the battery pack can be obtained by detecting and summarizing the data from sensors distributed in multiple locations on the battery pack.

[0044] The acquisition module can obtain the discharge current and internal resistance of the battery pack, then obtain the instantaneous heating power based on the discharge current and internal resistance, and obtain the average heat release power by taking the average of the instantaneous heating power over a fixed time period.

[0045] The calculation module is used to determine the target cooling power of the cooling unit based on the average heat generation power when the average heat generation power is greater than the heat generation power threshold and the average temperature of the battery pack is greater than the cooling temperature threshold.

[0046] For example, when the average heat generation power exceeds a heat generation power threshold and the average battery pack temperature exceeds a cooling temperature threshold, the calculation module obtains the corresponding target cooling power based on the average heat generation power using methods such as table lookup. In another embodiment, through real-vehicle calibration, a mathematical expression for the average heat generation power and the target cooling power is established for real-time calculation. It is understood that the target cooling power is typically greater than or equal to the average heat generation power to achieve power balance.

[0047] It is understood that the cooling temperature threshold specified in this embodiment can be a fixed value. In some embodiments, the cooling temperature threshold is a dynamic value calculated based on the vehicle's state parameters. As the environment and state of the vehicle change, the temperature threshold that allows the battery pack cooling to be turned on can be calculated more accurately. Compared with setting only a fixed threshold, it can identify and control the situation more accurately in advance.

[0048] The adjustment module is used to adjust the actual cooling power of the cooling unit to the target cooling power in order to balance the heat generation of the battery pack.

[0049] For example, the adjustment module adjusts the actual cooling power of the cooling unit by adjusting the speed of the compressor 101. When the current actual cooling power is lower than the target cooling power, the speed of the compressor 101 is increased, and vice versa. In another embodiment, the actual cooling power is adjusted by changing the opening of the expansion valve 103.

[0050] In one embodiment, the battery pack is cooled using a circulating liquid cooling method, such as... Figure 2 As shown, the cooling unit includes a battery circuit, which includes a battery cooler 104, a medium pump 105, and a cooling assembly 106 connected in sequence. The cooling assembly 106 is connected to the battery pack and can be a heat dissipation component such as a liquid cooling heat sink, which can be disposed inside the battery pack.

[0051] The battery cooler 104 is used for heat exchange between the battery circuit and the refrigerant circuit. For example, the battery cooler 104 includes a refrigerant channel and a cooling medium channel. The refrigerant from the expansion valve 103 circulates through the refrigerant channel, and the cooling medium from the medium pump 105 exchanges heat with the refrigerant through the cooling medium channel. After the temperature is reduced, it enters the cooling component 106 inside the battery pack.

[0052] In another embodiment, the battery pack cooling module can adopt a refrigerant direct cooling structure, with the cooling unit located at the battery pack, where the refrigerant evaporates and absorbs heat to achieve the cooling function.

[0053] The following description uses a battery pack cooling module employing a circulating liquid cooling solution.

[0054] In one embodiment, the acquisition module is further configured to acquire the actual cooling power of the cooling unit. The acquisition module also includes a first temperature sensor 107, a second temperature sensor 108, and a flow sensing unit. The first temperature sensor 107 is disposed at the medium outlet of the cooling component 106, the second temperature sensor 108 is disposed at the medium inlet of the cooling component 106, and the flow sensing unit is configured to sense the medium flow rate of the battery circuit.

[0055] It is understood that the first temperature sensor 107 and the second temperature sensor 108 respectively acquire the temperature of the cooling medium flowing out of the battery pack and the temperature of the cooling medium flowing into the battery pack, thereby calculating the temperature difference of the cooling medium, and further combining the medium flow rate and the specific heat capacity of the medium to obtain the actual cooling power of the cooling unit.

[0056] In addition, the flow sensing unit is exemplarily a flow sensor installed in the battery circuit, which can directly sense flow data; in one embodiment, the flow sensing unit is arranged in the controller of the medium pump 105, and the flow rate is calculated based on the speed of the medium pump 105 by collecting the rotation speed of the medium pump 105.

[0057] When the battery pack receives sufficient cooling, for example, if the average heat generation power of the battery pack is less than or equal to the heat generation power threshold within a certain period of time, the cooling device can shut off the battery pack cooling; or if the average temperature of the battery pack is less than or equal to the cooling temperature threshold within a certain period of time, the battery pack cooling can be shut off.

[0058] The vehicle battery cooling device provided in this application differs from traditional battery cooling systems that control cooling based on battery temperature. It determines the target cooling power based on the average heat generation power and controls the cooling unit accordingly, achieving the effect of identifying and precisely controlling the battery pack temperature before heat accumulation and temperature rise. Furthermore, the battery cooling device in this application employs a power balancing method, ensuring that the battery pack temperature remains within a stable range even under complex operating conditions such as racing tracks or rapid acceleration and deceleration.

[0059] It is understood that the various modules in the aforementioned vehicle battery cooling system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the operations corresponding to each module.

[0060] In one embodiment, a vehicle battery cooling control method is provided, which can be applied to vehicle battery cooling devices employing either circulating liquid cooling or direct refrigerant cooling. The following description uses a control method based on circulating liquid cooling as an example. Figure 3 This includes the following steps:

[0061] Step 201: Obtain the average heat generation power and average temperature of the battery pack.

[0062] The average heat generation power can be determined based on power sampling values ​​over a certain period of time, and the average temperature of the battery pack can be calculated based on real-time temperature sensing by multiple sensors installed in the battery pack.

[0063] Step 202: Determine whether the average heat generation power is greater than the heat generation power threshold and whether the average temperature of the battery pack is greater than the cooling temperature threshold. When the average heat generation power is greater than the heat generation power threshold and the average temperature of the battery pack is greater than the cooling temperature threshold, determine the target cooling power of the cooling unit based on the average heat generation power.

[0064] The heat generation power threshold is the minimum heat generation power value that triggers battery cooling, and it can be calibrated and matched according to the battery model and vehicle type.

[0065] The cooling temperature threshold is the temperature threshold that triggers the battery cooling to start. It can be obtained by calibration on a real vehicle or by dynamic calculation.

[0066] It is understandable that, considering the heat loss caused by factors such as the battery pack structure, the target cooling power can be greater than the average heat generation power. On the other hand, when the vehicle is driving under special conditions, such as in a low-temperature environment, thanks to the vehicle's good heat dissipation, the target cooling power may be less than the average heat generation power. Therefore, the correspondence between the average heat generation power and the target cooling power can be established through actual vehicle calibration.

[0067] Step 203: Adjust the actual cooling power of the cooling unit to the target cooling power to balance the heat generation of the battery pack.

[0068] In the vehicle battery cooling device described above, the actual cooling power of the cooling unit can be adjusted by adjusting the speed of the compressor 101 and / or the opening of the expansion valve 103.

[0069] The vehicle battery cooling control method of this application determines the timing of battery cooling by using the average heat generation power and the average temperature of the battery pack, and further determines the target cooling power based on the average heat generation power. The actual cooling power of the cooling unit is then adjusted according to the target cooling power. Compared with the traditional control method based on battery pack temperature, the control method of this application can introduce cooling measures before the temperature rises further, thereby achieving advanced control and stable temperature. On the other hand, determining the target cooling power based on the average heat generation power and performing power balance adjustment can make the battery pack temperature more stable and improve the system adjustment capability under special operating conditions (such as track conditions, rapid acceleration and deceleration conditions).

[0070] In one embodiment, the cooling temperature threshold is determined based on vehicle state parameters, including battery pack charge, average battery pack temperature, and ambient temperature, wherein the cooling temperature threshold is negatively correlated with the battery pack charge, average battery pack temperature, and ambient temperature.

[0071] In actual implementation, the vehicle's controller, such as the Vehicle Domain Controller (VDC), receives real-time data from the battery management system, including the battery pack's State of Charge (SOC) and average battery pack temperature (BatTemp). Avg Discharge current I Bat At the same time, the ambient temperature is collected in real time.

[0072] VDC is based on the battery pack's state of charge (SOC) and average battery pack temperature (BatTemp). Avg and ambient temperature (Temp) Amb The allowable cooling temperature threshold Thd1 for battery cooling is calculated. For example, the allowable cooling temperature threshold can be determined according to the following mathematical expression:

[0073] Thd1=f(SOC)×K1+f(BatTemp Avg )×K2+f(Temp Amb )×K3

[0074] Where f(SOC) is the first parameter with the battery pack's SOC as input; the higher the SOC, the lower the cooling temperature threshold; f(BatTemp Avg (Based on the average temperature of the battery pack, BatTemp) Avg The second parameter is the input; a higher average battery pack temperature will result in a lower cooling temperature threshold. Amb (Based on ambient temperature) Amb The third parameter is the ambient temperature. The higher the ambient temperature, the lower the cooling temperature threshold will be. K1, K2, and K3 are the first, second, and third coefficients, respectively, which can be calibrated and matched according to the battery pack model and vehicle model.

[0075] Thd1 can more accurately calculate the cooling temperature threshold that allows the battery cooling to be turned on, depending on the vehicle's environment and condition. Compared to setting only a fixed threshold, it can identify and control the temperature more accurately in advance.

[0076] In one embodiment, obtaining the average heat dissipation power of the battery pack includes obtaining the discharge current and internal resistance of the battery pack, obtaining the instantaneous heat dissipation power based on the discharge current and the internal resistance, and obtaining the average heat dissipation power by averaging the instantaneous heat dissipation power over a fixed time period, wherein the internal resistance is determined based on the battery pack charge, the average temperature of the battery pack, and the voltage of the individual battery cells.

[0077] For example, the instantaneous heating power P0 can be calculated according to the following mathematical expression:

[0078] P0=(I Bat ) 2 ×R(SOC, T, V)

[0079] Wherein, R is the internal resistance, the value of which is affected by SOC, battery pack temperature T (average temperature or local temperature) and battery cell voltage V. In the actual implementation process, a fitting relationship can be established based on battery pack design and testing.

[0080] The average heat generation power P1 of the battery within time T1 is calculated based on P0. When P1 > Pmin (heat generation power threshold) and the average temperature of the battery pack > Thd1, the VDC control thermal management system starts the compressor 101, fan, expansion valve 103, and medium pump 105 to activate the battery cooling function.

[0081] In one embodiment, the actual cooling power is determined according to the following mathematical expression:

[0082] P c = (Tout - Tin) × L × C

[0083] Among them, P c The actual cooling power is Tout, the temperature of the cooling medium flowing out of the battery pack is Tin, the temperature of the cooling medium flowing into the battery pack is L, the medium flow rate is C, and the specific heat capacity of the medium is C.

[0084] like Figure 2 As shown, in the battery circuit consisting of the medium pump 105, the battery cooler 104, and the cooling assembly 106, the cooling medium can be water. Tout and Tin are uploaded by temperature sensors arranged at the inlet and outlet of the cooling assembly 106, and the temperature is calculated by VDC. VDC controls the medium pump 105 to meet the flow rate requirements. The flow rate can be obtained through experimental testing based on the battery pack and system design.

[0085] In one embodiment, the target cooling power is determined according to the following mathematical expression:

[0086] P tag =P1×K4

[0087] Among them, P tag The target cooling power is P1, the average heat generation power is K4, and the fourth coefficient can be determined based on actual vehicle calibration. The cooling of the battery pack is dynamically adjusted using a power balance cooling method to keep the battery pack temperature within a certain range, thus achieving more precise control.

[0088] In one embodiment, adjusting the actual cooling power includes determining a target speed of the compressor 101 based on the average heat generation power, and controlling the compressor 101 based on the target speed.

[0089] For example, when the average heat generation power is high, the target rotation speed has a larger value, and the more cooling capacity, the higher the cooling power of the cooling unit.

[0090] In another embodiment, adjusting the actual cooling power includes determining a target opening of the expansion valve 103 based on the average heat generation power, and controlling the expansion valve 103 based on the target opening to balance the heat generation of the battery.

[0091] For example, when the average heat generation power is high, the expansion valve 103 has a larger opening, allowing more liquid refrigerant to enter the battery cooler 104 for evaporation and heat absorption. The cooling water in the battery circuit can have a lower temperature or increase the cooling water circulation speed while maintaining a stable temperature, thereby increasing the actual cooling power.

[0092] In one embodiment, when the average heat generation power P1 ≤ Pmin within time T2, and the average temperature of the battery pack BatTemp Avg After ≤Thd1, VDC controls the vehicle battery cooling device to turn off the battery cooling function.

[0093] like Figure 4 As shown, the control flow of the vehicle battery cooling control method of this application is illustrated. From vehicle startup, the system acquires parameters such as battery discharge current, internal resistance, average battery pack temperature, battery pack charge, and ambient temperature. It calculates the temperature threshold for activating battery pack cooling and the average heat generation power of the battery pack. It then determines whether the average battery pack temperature exceeds the cooling temperature threshold and whether the average heat generation power exceeds the heat generation power threshold. If both conditions are met, the cooling system is activated. The system calculates and controls the cooling power of the cooling device to ensure the actual cooling power P... c To achieve the target cooling power P tag =P1×K4. During the control process, the inlet and outlet water temperatures of the battery pack are monitored in real time. When the average heat generation power and average temperature of the battery pack drop below the corresponding threshold, the battery cooling function can be deactivated.

[0094] In the above-mentioned vehicle battery cooling control method, the average heat generation power and average temperature of the battery pack are used to determine whether there is a trend of further temperature rise in the battery pack. When both conditions are met, the target cooling power required for cooling is determined based on the average heat generation power. Before the battery pack temperature rises further, the heat generation is offset by power balance, which improves the problem of battery cooling lag and avoids the limitation of power performance caused by the rise in battery pack temperature.

[0095] It should be understood that, although Figure 3-4 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 3-4At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0096] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0097] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A vehicle battery cooling device, characterized in that, The device includes: A battery pack cooling module includes a refrigerant circuit and a cooling unit connected to the refrigerant circuit. The refrigerant circuit includes a compressor, a condenser, and an expansion valve connected in sequence. The cooling unit is connected to the battery pack to provide cooling power to the battery pack. The acquisition module is used to acquire the average heat generation power and average temperature of the battery pack. The calculation module is used to determine the target cooling power of the cooling unit based on the average heat generation power when the average heat generation power is greater than the heat generation power threshold and the average temperature of the battery pack is greater than the cooling temperature threshold. An adjustment module is used to adjust the actual cooling power of the cooling unit to the target cooling power in order to balance the heat generation of the battery pack.

2. The vehicle battery cooling device according to claim 1, characterized in that, The cooling unit includes a battery circuit, which includes a battery cooler, a medium pump, and a cooling assembly connected in sequence. The cooling assembly is connected to the battery pack.

3. The vehicle battery cooling device according to claim 2, characterized in that, The acquisition module is also used to acquire the actual cooling power of the cooling unit. The acquisition module also includes a first temperature sensor, a second temperature sensor, and a flow sensing unit. The first temperature sensor is located at the medium outlet of the cooling component, the second temperature sensor is located at the medium inlet of the cooling component, and the flow sensing unit is used to sense the medium flow rate of the battery circuit.

4. A method for controlling vehicle battery cooling, characterized in that, The vehicle battery cooling device according to any one of claims 1-3 comprises: Obtain the average heat generation power and average temperature of the battery pack; When the average heat generation power is greater than the heat generation power threshold and the average temperature of the battery pack is greater than the cooling temperature threshold, the target cooling power of the cooling unit is determined based on the average heat generation power, and the actual cooling power of the cooling unit is adjusted to the target cooling power to balance the heat generation of the battery pack.

5. The vehicle battery cooling control method according to claim 4, characterized in that, The process of obtaining the average heat generation power and average temperature of the battery pack then includes: The cooling temperature threshold is determined based on state parameters, including battery pack charge, average battery pack temperature, and ambient temperature. The cooling temperature threshold is negatively correlated with the battery pack charge, average battery pack temperature, and ambient temperature.

6. The vehicle battery cooling control method according to claim 5, characterized in that, The cooling temperature threshold is determined according to the following mathematical expression: Thd1=f(SOC)×K1+f(BatTemp Avg )×K2+f(Temp Amb )×K3 Where Thd1 is the cooling temperature threshold, f(SOC) is the first parameter with the battery pack SOC as input, and f(BatTemp) is the first parameter with the battery pack SOC as input. Avg (Based on the average temperature of the battery pack, BatTemp) Avg The second parameter is f(Temp) as input. Amb (Based on ambient temperature) Amb K1, K2, and K3 are the third input parameter, and K1, K2, and K3 are the first, second, and third coefficients, respectively.

7. The vehicle battery cooling control method according to claim 4, characterized in that, The process of obtaining the average heat generation power of the battery pack includes: The discharge current and internal resistance of the battery pack are obtained, the instantaneous heating power is obtained based on the discharge current and the internal resistance, and the average heating power is obtained by averaging the instantaneous heating power over a fixed time period. The internal resistance is determined based on the battery pack charge, the average temperature of the battery pack, and the voltage of the individual battery cells.

8. The vehicle battery cooling control method according to claim 4, characterized in that, Adjusting the actual cooling power to the target cooling power includes: The actual cooling power is determined based on the following mathematical expression: P c (All-Tin)×L×C Among them, P c The actual cooling power is Tout, the temperature of the cooling medium flowing out of the battery pack is Tin, the temperature of the cooling medium flowing into the battery pack is L, the medium flow rate is C, and the specific heat capacity of the medium is C.

9. The vehicle battery cooling control method according to claim 4, characterized in that, The target cooling power is determined according to the following mathematical expression: P tag =P1×K4 Among them, P tag P1 is the target cooling power, P1 is the average heat generation power, and K4 is the fourth coefficient.

10. The vehicle battery cooling control method according to claim 4, characterized in that, Adjusting the actual cooling power of the cooling unit to the target cooling power includes: The target speed of the compressor is determined based on the average heat generation power, and the compressor is controlled based on the target speed to balance the heat generation of the battery; and / or, The target opening degree of the expansion valve is determined based on the average heat generation power, and the expansion valve is controlled based on the target opening degree to balance the heat generation of the battery.

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