Battery thermal management method, system, and computer program product

Abstract

The application provides a battery thermal management method, system and computer program product, the method comprising: according to the liquid cooling strategy type set by the user, controlling the liquid cooling machine to dissipate heat in a first or second strategy;The first strategy comprises according to the mapping relationship between the current ambient temperature and the maximum temperature of the battery, the refrigeration point of the liquid cooling machine is dynamically updated according to the current ambient temperature and the maximum temperature of the battery;In the process, the door access state is continuously monitored, and when the door access alarm occurs, the liquid cooling machine is forced to enter the water circulation mode of stopping refrigeration;When the door access alarm is removed, the refrigeration is restored;The second strategy comprises: when the liquid cooling machine is refrigerating and the cooling liquid temperature is lower than the preset stop intervention point, the liquid cooling machine is forced to enter the water circulation mode, and when the cooling liquid temperature rises to the stop intervention point, the liquid cooling machine enters the automatic mode. By using the technical scheme, the system energy efficiency and environmental adaptability can be significantly improved, the hidden danger can be prevented in advance, and the reliability can be enhanced.

Description

Technical Field

[0001] This invention relates to the field of battery heat dissipation control technology, and in particular to a battery thermal management method, system, and computer program product. Background Technology

[0002] The Battery Thermal Management System (BTMS) is the core system ensuring the safe, long-life, and high-performance operation of energy storage batteries. Currently, air cooling and liquid cooling are the two mainstream technologies. Air cooling solutions typically use air conditioning to cool the entire space inside the battery cabinet, supplemented by internal fans to promote airflow circulation and expel heat outside the cabinet. Liquid cooling solutions, on the other hand, use liquid cooling plates in contact with the battery cells, relying on coolant to carry heat to an external liquid chiller for dissipation. Due to its high efficiency and good temperature uniformity, it is becoming the preferred choice for large-scale and high-power-density energy storage systems.

[0003] Defects and shortcomings of existing technology: Rigid control strategies and poor environmental adaptability: Existing liquid cooling systems mostly use on-off control or PID regulation with fixed temperature thresholds, which cannot adaptively adjust operating parameters according to environmental changes such as seasons and regions; they are prone to "overcooling" in cool environments, resulting in high energy consumption; and they may be "undercooled" in extreme high-temperature environments, resulting in poor temperature uniformity; the system lacks self-optimization capabilities and has a low annual energy efficiency ratio (COP); The safety hazards are prominent and there is a lack of proactive protection mechanisms: existing traditional solutions mostly adopt a passive approach of alarming after the fact to deal with the risk of condensation generated by the liquid cooling system when it is running in a high temperature and high humidity environment. They lack proactive intervention strategies based on environmental temperature and humidity prediction and intervention in advance, which poses a short circuit risk. At the same time, there is also a lack of effective protection against the problem that the coolant temperature may be too low in low temperature environments, which may damage the battery cells. The system lacks sufficient reliability and has a rudimentary fault response strategy: The system heavily relies on the main communication link. In the event of a communication interruption or a partial failure of the liquid cooler, such as an access control alarm, the only option is usually to shut down the system completely. This results in the complete failure of the thermal management function and exposes the battery system to the risk of thermal runaway or low-temperature damage. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, embodiments of the present invention provide a battery thermal management method, system, and computer program product.

[0005] To achieve the above objectives, on the one hand, a battery thermal management method is provided, applied to a battery thermal management system, the battery thermal management system comprising: a liquid cooling system, wherein the liquid cooling system includes a liquid chiller, and the battery thermal management method comprising: Based on the liquid cooling strategy type set by the user, the liquid chiller is controlled to dissipate heat using either a first control strategy or a second control strategy; the first control strategy is an adaptive strategy implemented by automatically controlling the outlet water temperature of the liquid chiller; the second control strategy is a control strategy implemented by controlling the cell temperature of the battery; in the second control strategy, control intervention is performed when predetermined conditions are met. The control strategy for the liquid chiller to dissipate heat includes: Continuously monitor the battery cell temperature, ambient temperature, and liquid cooler outlet water temperature; Based on the pre-set mapping relationship between ambient temperature and liquid cooling system cooling point, and the mapping relationship between battery cell maximum temperature and liquid cooling system cooling point, the liquid cooling system cooling point is dynamically updated according to the current ambient temperature and battery cell maximum temperature, and the liquid cooling system performs cooling control according to the updated liquid cooling system cooling point. During the cooling control process, the access control status of the battery cabinet door is continuously monitored. When an access control alarm occurs, the liquid chiller is forced to enter the water circulation mode. In the water circulation mode, cooling is stopped and only the coolant circulates. When the access control alarm is cleared, the forced shutdown of cooling is canceled. The second control strategy for controlling the liquid chiller to dissipate heat includes: Continuously monitor the battery cell temperature and coolant temperature; When the maximum temperature of the battery cell is higher than the cooling point, the liquid chiller is cooling and the coolant temperature is lower than the preset stop intervention point, the liquid chiller is forced to enter the water circulation mode, and when the coolant temperature rises to the stop intervention point, the liquid chiller is controlled to enter the automatic mode.

[0006] Preferably, the battery thermal management method, which dynamically updates the liquid cooling point based on the current ambient temperature and the maximum cell temperature, includes: Determine the first cooling point based on the current ambient temperature; Determine the second cooling point based on the current maximum temperature of the battery cell; The lower of the first and second cooling points is selected as the updated cooling point of the liquid cooling system.

[0007] Preferably, the battery thermal management method allows users to set the liquid cooling strategy type by setting a liquid cooling strategy type parameter.

[0008] Preferably, in the battery thermal management method, the step of controlling the liquid cooler to enter automatic mode when the coolant temperature rises to the stop intervention point includes: Determine whether the liquid chiller is currently in automatic mode; if so, maintain automatic mode; otherwise, after a delay of N seconds, control the liquid chiller to enter automatic mode; where N is a preset value.

[0009] Preferably, in the battery thermal management method, the battery thermal management system further includes: an air-cooling system; the air-cooling system includes fans corresponding to each battery module; the battery thermal management method further includes: The value of the cooling type parameter determines whether the user-set cooling type is air cooling or liquid cooling. When the user-set cooling type is air cooling, the air cooling system is activated for air cooling control; when the user-set cooling type is liquid cooling, the liquid cooling system is activated for liquid cooling control.

[0010] Preferably, the battery thermal management method includes the step of activating the air-cooling system for air-cooling control, which involves cyclically executing the following steps for each battery module: Calculate the difference between the temperature of the battery module and the preset target temperature; Based on the interval where the difference is located and the preset correspondence between the interval where the difference is located and the fan speed level, the fan speed level corresponding to the difference is determined. The fan corresponding to the battery module is controlled to the determined fan speed level.

[0011] Preferably, in the battery thermal management method, the preset correspondence between the range of the difference and the fan speed level includes: When the difference is greater than 4℃, the corresponding fan speed setting is the high speed setting; When the difference is greater than 2℃ and less than or equal to 4℃, the corresponding fan speed setting is medium speed. When the difference is less than or equal to 2℃, the corresponding fan speed setting is low speed.

[0012] On the other hand, a battery thermal management system is also provided, including a liquid cooling system and an air cooling system, and further including a memory and a processor, wherein the memory stores at least one program, which is executed by the processor to implement the steps of the battery thermal management method as described above.

[0013] In another aspect, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of any of the battery thermal management methods described above. The above technical solution has the following technical effects: By employing an adaptive strategy that automatically controls the outlet water temperature of the liquid chiller and dynamically updates the cooling point in liquid cooling mode, operating parameters can be automatically optimized to adapt to different environments. This avoids the energy waste or insufficient heat dissipation defects caused by fixed strategies, improving the system's annual energy efficiency and environmental adaptability. By forcing the liquid chiller into the water circulation mode when it is cooling and the coolant temperature is below the preset stop intervention point, potential alarm hazards such as condensate and low-temperature cold shock can be transformed into preventative measures, enhancing safety. In liquid cooling mode, differentiated handling of access control alarm faults, rather than simple shutdown, provides fault degradation operation capability, enabling the system to maintain basic heat exchange even when main functions are limited, providing a buffer time for operation and maintenance, and greatly improving the system's availability and reliability.

[0014] In a further embodiment, by implementing zoned temperature control and graded speed adjustment of the corresponding fans for each battery module in the air-cooling heat dissipation process, differentiated and refined heat dissipation of the battery cluster is achieved, effectively reducing the temperature difference of the cells within the cluster, slowing down the uneven degradation of the battery pack, and thus extending the overall lifespan of the battery. Attached Figure Description

[0015] Figure 1 This is a schematic flowchart of a battery thermal management method according to an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the parameter mapping relationship of a liquid chiller when the liquid chiller executes an adaptive strategy, as shown in one embodiment of the present invention. Figure 3 A flowchart illustrating the control strategy for an air-cooled air conditioner; Figure 4 A schematic diagram of the control flow for the fan speed sub-process; Figure 5 This is a schematic diagram of the liquid cooling control process in the battery thermal management method of this invention. Detailed Implementation

[0016] To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention, primarily used to illustrate the embodiments and to explain the operating principles of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these drawings, those skilled in the art should be able to understand other possible implementations and the advantages of the present invention. Components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0017] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0018] Example 1: Figure 1This is a schematic flowchart of a battery thermal management method according to an embodiment of the present invention. The battery thermal management method of this embodiment is applied to a battery thermal management system, which includes a liquid cooling system, wherein the liquid cooling system includes a liquid chiller, and the battery thermal management method includes: Based on the liquid cooling strategy type set by the user, the liquid cooler is controlled to dissipate heat using either a first control strategy or a second control strategy. The first control strategy is an adaptive strategy implemented by automatically controlling the outlet water temperature of the liquid cooler. The second control strategy is a control strategy implemented by controlling the cell temperature of the battery. In the second control strategy, control intervention is performed when predetermined conditions are met. In a specific implementation, the first control strategy is called an adaptive strategy, and the second control strategy is called an intervention strategy, such as the liquid cooler cell temperature weighting and battery management system (BMS) intervention strategy. The control strategy for the liquid chiller to dissipate heat includes: Continuously monitor the battery cell temperature, ambient temperature, and liquid cooler outlet water temperature; Based on the pre-set mapping relationship between ambient temperature and liquid cooling system cooling point, and the mapping relationship between battery cell maximum temperature and liquid cooling system cooling point, the liquid cooling system cooling point is dynamically updated according to the current ambient temperature and battery cell maximum temperature, and the liquid cooling system performs cooling control according to the updated liquid cooling system cooling point. During the cooling control process, the access control status of the battery cabinet door is continuously monitored. When an access control alarm occurs, the liquid chiller is forced to enter water circulation mode. In water circulation mode, cooling is stopped and only the coolant circulates. When the access control alarm is cleared, the forced shutdown of cooling is canceled. In one specific implementation, whether cooling is restored when the access control is cleared depends on whether the cooling strategy before the access control alarm was triggered. If so, cooling is restored; otherwise, cooling is not restored. The second control strategy for controlling the liquid chiller to dissipate heat includes: Continuously monitor the battery cell temperature and coolant temperature; When the maximum temperature of the battery cell is not higher than the cooling point, the liquid chiller is cooling and the coolant temperature is lower than the preset stop intervention point, the liquid chiller is forced to enter the water circulation mode, and when the coolant temperature rises to the safety intervention point, the liquid chiller is controlled to enter the automatic mode.

[0019] In one specific implementation, dynamically updating the liquid cooling mechanism's cooling point based on the current ambient temperature and the cell's maximum temperature includes: Determine the first cooling point based on the current ambient temperature; Determine the second cooling point based on the current maximum temperature of the battery cell; The lower of the first and second cooling points is selected as the updated cooling point of the liquid cooling system.

[0020] Figure 2 Examples of the mapping relationships between the pre-set ambient temperature and the liquid cooling system's cooling point, and between the cell's maximum temperature and the liquid cooling system's cooling point, are given in the first control strategy. For example... Figure 2 Preferably, in addition to the cooling point, the mapping relationship also includes other corresponding liquid chiller parameters, including: cooling point, cooling hysteresis and heating hysteresis.

[0021] Example 2: Based on Embodiment 1, in this embodiment of the present invention, the battery thermal management system further includes: an air-cooling system; the air-cooling system includes fans corresponding to each battery module of the battery; the battery thermal management method of this embodiment of the present invention further includes: determining whether the cooling type set by the user is air-cooling mode or liquid-cooling mode according to the value of the cooling type parameter; when the cooling type set by the user is air-cooling mode, starting the air-cooling system for air-cooling control; when the cooling type set by the user is liquid-cooling mode, starting the liquid-cooling system for liquid-cooling control.

[0022] In one specific implementation, the battery thermal management method of this invention is executed by a control unit, such as a CBMS (Battery Thermal Management System), within the battery thermal management system. This control unit includes a memory and a processor. The processor executes a computer program stored in the memory to perform the steps of the battery thermal management method of this invention. In another specific implementation, the aforementioned computer program is implemented as a software platform. This software platform determines whether to operate in air-cooled or liquid-cooled mode using a system-level configuration parameter, such as the parameter System_Cooling_Type. In yet another specific implementation, this parameter is written to the non-volatile memory of the CBMS via a host computer tool using the Modbus TCP protocol during system integration. This parameter is read during system power-on initialization, and the system enters the corresponding cooling mode based on the read parameter value.

[0023] (I) Specific Implementation Method of Air-Cooled Mode Configuration method: Set the system-level configuration parameter System_Cooling_Type to air-cooling mode, i.e., AIR_COOLING.

[0024] Control process: After the system is powered on, the CBMS reads the configuration, initializes the drive circuit of the air-cooled system, and ignores the existence of the liquid-cooled system. At this time, the liquid-cooling mode will be automatically disabled. The air-cooled system includes: air conditioning compressor, fan, and damper actuator.

[0025] CBMS continuously monitors the temperature of each battery module within the battery cluster.

[0026] Entering the air-cooled fine control cycle: Step 1, Enable and Diagnose: Check if the system power supply and air conditioning status are normal.

[0027] Step 2, Zone Calculation: For each battery module, calculate the difference between the module temperature and the preset target temperature for each module. The difference is represented by ΔT.

[0028] Step 3, graded speed control: Based on the range of ΔT for each module, i.e., the preset threshold range, the speed of the cooling fan corresponding to that module is independently controlled. In specific implementation, a pre-defined correspondence between the difference range and the cooling fan speed is established, and the speed of the cooling fan for the corresponding module is set according to this correspondence. For example, in one specific implementation: when ΔT > 4℃, the fan is set to high speed; when 2℃ < ΔT ≤ 4℃, the fan is set to medium speed; when ΔT ≤ 2℃, the fan is set to low speed. The thresholds 2℃ and 4℃ used for the above zoning can be adjusted according to actual scenarios and needs; the specific number of speed levels can also be adjusted according to actual needs and scenarios, which will not be elaborated here.

[0029] By repeating the above steps, heat dissipation can be achieved on demand, minimizing the temperature difference between cells within the cluster.

[0030] in, Figure 3 A flowchart illustrating the control strategy for an air-cooled air conditioner; Figure 4 This is a schematic diagram of the control flow for the fan speed sub-process. Figure 3 The operating modes of the fan are explained as follows: 0x02: Fan is waiting for power-on delay; 0x03: Fan power-on delay ends; 0x04: Fan control is disabled; 0x05: Manual control; 0x00: Fan is off.

[0031] like Figure 3 The air-cooled air conditioner control strategy includes: determining whether manual control is enabled; if so, performing manual control and controlling the air-cooled air conditioner according to the manual control command; if not, when the system is powered on and the air conditioner is fault-free, obtaining the highest temperature of the battery cluster, and when the highest cluster temperature is greater than or equal to the preset high-temperature fan start temperature, entering the fan speed determination sub-process, and sending control commands to all fans in the battery module; if the highest cluster temperature does not meet the requirement of being greater than or equal to the preset high-temperature fan start temperature, further determining whether the highest cluster temperature is less than or equal to the preset high-temperature fan stop temperature and the lowest cluster temperature is greater than or equal to the preset low-temperature fan stop temperature; if so, setting the fan operating mode to 0x00 to stop the fan, and further determining whether the fan has stopped; if it has stopped, updating the fan operating status and fault status; if it has not stopped, sending all fan stop commands and updating the fan operating status and fault status.

[0032] like Figure 4The fan speed sub-process includes, for each battery module, first determining whether the module is operating under a high-temperature strategy based on the module temperature. If so, the temperature difference X between the module's highest temperature and the preset high-temperature fan start temperature is further calculated, and as mentioned above, the speed level of the corresponding cooling fan for that module is determined based on the range of the temperature difference. If the module is not operating under a high-temperature strategy, the temperature difference Y between the module's lowest temperature and the preset low-temperature fan start temperature is further calculated, and as mentioned above, the speed level of the corresponding cooling fan for that module is determined based on the range of the temperature difference. This achieves fine-grained air-cooling control cycle for each module's fan.

[0033] The air-cooling control scheme of this invention achieves refined temperature field management and effectively extends battery life: through the "zoned temperature control" and "graded speed regulation" steps in the air-cooling sub-process, differentiated and refined heat dissipation of the battery cluster is achieved, effectively reducing the temperature difference (ΔT) of the cells within the cluster, slowing down the uneven degradation of the battery pack, and thus extending the overall life.

[0034] (II) Specific Implementation Method of Liquid Cooling Mode Configuration method: Set the system-level configuration parameter System_Cooling_Type to liquid cooling mode, such as LIQUID_COOLING.

[0035] Secondary strategy configuration: Building upon the liquid cooling mode, the specific liquid cooling strategy type is configured via another software parameter, such as `Liquid_Cooling_Strategy`. Optional values ​​for the liquid cooling strategy type include: adaptive strategy (ADAPTIVE_STRATEGY) and intervention strategy (INTERVENTION_STRATEGY). The specific value of this parameter determines the type of liquid cooling control used, and consequently, the branches of the liquid cooling control flow. Figure 5 This is a schematic diagram of the liquid cooling control process in the battery thermal management method of this invention.

[0036] After the system is powered on, the control unit of the battery thermal management system, namely the CBMS, reads the configuration and initializes the liquid chiller parameters, which include: cooling point, heating point, cooling hysteresis, and heating hysteresis.

[0037] CBMS continuously monitors parameters such as battery temperature, ambient temperature, and liquid cooler outlet water temperature.

[0038] Execution as Figure 5 The liquid cooling strategy flow shown is as follows: Step A, Communication and Power-on Assurance: Confirm successful communication with the liquid chiller. If the liquid chiller is not powered on, send a power-on command every 10 seconds until it is successfully powered on.

[0039] Step B, Strategy Selection: The selected liquid cooling strategy type is determined by setting the Liquid_Cooling_Strategy parameter; this step is used to set the control target and confirm the mode.

[0040] If the adaptive strategy is ADAPTIVE_STRATEGY, i.e., the first control strategy, then the CBMS's adaptive strategy is entered. The control target is the outlet water temperature of the liquid chiller. The CBMS will combine the ambient temperature and the highest cell temperature to select parameter thresholds for cooling point, heating point, cooling hysteresis, and heating hysteresis. In one specific implementation, based on the pre-set mapping relationship between parameters, such as... Figure 2 The table shown is used to select parameter thresholds. After selection, the parameters will be updated to the liquid chiller, and the operating mode of the liquid chiller will be set to control the outlet water temperature, i.e., the outlet water temperature.

[0041] Configure the liquid chiller to use "outlet water temperature" as the control target and set it to operate in "automatic mode" via commands. Set a delay afterward and confirm successful configuration; if it fails, reset the settings to ensure reliable command execution. By continuously monitoring the access control status, if an access control alarm is detected, such as one caused by the battery cabinet door being accidentally opened, the liquid chiller is immediately forced into "water circulation mode." In this mode, only the pump operates, and the compressor stops running. This is intended to stop cooling, raise the temperature of the liquid cooling plates and pipes, and prevent their low-temperature surfaces from coming into contact with the high-humidity outside air, thus preventing the formation of condensation and effectively preventing the risk of electrical short circuits caused by condensation, until the alarm is cleared and the system returns to normal.

[0042] If no abnormalities are found, based on the ambient temperature and cell temperature, as referenced... Figure 2 The mapping relationship in the system is used to dynamically update the refrigeration and / or heating setpoints of the liquid chiller, thus completing closed-loop control.

[0043] If the liquid cooling strategy is an intervention strategy (INTERVENTION_STRATEGY), then the "cell temperature weighting & BMS intervention strategy" is executed. Under this strategy, the control target is the battery cell temperature. The liquid cooler executes an automatic strategy based on the real-time highest and lowest cell temperatures, while the CBMS monitors the temperature in real time and intervenes when necessary based on the actual temperature conditions. This strategy aims to solve the dynamic imbalance between battery heat generation and the cooling response of the liquid cooling system. Its core principle is to actively intervene in the liquid cooler's cooling strategy to prevent the coolant temperature from becoming too low due to excessively rapid cooling, thereby ensuring that the surface temperature of the liquid cooling plate in contact with the cell is always maintained within a safe range. This achieves two goals: it avoids "cold shock" to the cell from the low-temperature coolant, extending battery life; and it ensures that the cold plate temperature is above the ambient dew point, fundamentally solving the problem of condensation and ensuring system electrical safety. In one specific implementation, when using an intervention strategy for control, the liquid chiller is set to use the cell temperature as the control target, and its operating mode is set to automatic mode. A predetermined delay, such as a certain number of seconds, is set afterward to confirm successful mode setting; if it fails, the setting is repeated.

[0044] A stop-intervention point is pre-defined; for example, 18℃; this stop-intervention point is pre-selected through experiments. The coolant temperature is continuously monitored. If it falls below the intervention point, the CBMS will proactively intervene, forcibly adjusting the operating target of the liquid chiller or putting it into "water circulation mode" to avoid condensation or low-temperature damage. In one specific implementation, the selectable control modes of the liquid chiller include: fully automatic mode, water circulation mode, cooling mode, and heating mode; and a water circulation mode in which only the pump operates and the compressor does not operate. In one specific implementation, the coolant is an aqueous solution of ethylene glycol.

[0045] Once the water temperature rises above the stop intervention threshold, the liquid chiller is instructed to enter automatic mode. During this process, if the highest cell temperature is higher than the cooling point temperature, the liquid chiller will continue to cool.

[0046] In this embodiment of the invention, two safety conditions are continuously assessed during the automatic operation of the liquid chiller: Anti-condensation or low-temperature intervention: If the system is cooling and the water temperature is lower than the dynamically calculated stop intervention point (this point combines the ambient dew point temperature and the low-temperature protection threshold of the battery cell, and is preset), the liquid chiller will be forced to enter "water circulation mode", that is, only the pump works and the compressor does not work, and cooling will stop until the water temperature rises back to the safe point above the stop intervention point. Access control alarm handling: If an access control alarm is triggered, the liquid chiller will be forcibly set to "water circulation mode" until the alarm is cleared.

[0047] During the liquid cooling process, if there is no safety intervention, the system will dynamically update the cooling setpoint of the liquid chiller according to the current ambient temperature and cell temperature.

[0048] Example 3: A battery thermal management system is characterized by a liquid cooling system and an air cooling system, and further includes a memory and a processor, wherein the memory stores at least one program, which is executed by the processor to implement the steps of the battery thermal management method as described above.

[0049] Furthermore, as an executable solution, the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc. The processor is the control center of the computer unit, connecting various parts of the entire computer unit via various interfaces and lines.

[0050] The memory can be used to store the computer programs and / or modules. The processor implements various functions of the computer unit by running or executing the computer programs and / or modules stored in the memory and by calling data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory and may also include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital card (SD card), flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0051] Example 4: The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps described above.

[0052] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A battery thermal management method, applied to a battery thermal management system, the battery thermal management system comprising: A liquid cooling system, comprising a liquid chiller, characterized in that the battery thermal management method includes: Based on the liquid cooling strategy type set by the user, the liquid chiller is controlled to dissipate heat using either a first control strategy or a second control strategy; the first control strategy is an adaptive strategy implemented by automatically controlling the outlet water temperature of the liquid chiller; the second control strategy is a control strategy implemented by controlling the cell temperature of the battery; in the second control strategy, control intervention is performed when predetermined conditions are met. The control strategy for the liquid chiller to dissipate heat includes: Continuously monitor the battery cell temperature, ambient temperature, and liquid cooler outlet water temperature; Based on the pre-set mapping relationship between ambient temperature and liquid cooling system cooling point, and the mapping relationship between battery cell maximum temperature and liquid cooling system cooling point, the liquid cooling system cooling point is dynamically updated according to the current ambient temperature and battery cell maximum temperature, and the liquid cooling system performs cooling control according to the updated liquid cooling system cooling point. During the cooling control process, the access control status of the battery cabinet door is continuously monitored. When an access control alarm occurs, the liquid chiller is forced to enter the water circulation mode. In the water circulation mode, cooling is stopped and only the coolant circulates. When the access control alarm is cleared, the forced shutdown of cooling is canceled. The second control strategy for controlling the liquid chiller to dissipate heat includes: Continuously monitor the battery cell temperature and coolant temperature; When the maximum temperature of the battery cell is higher than the cooling point, the liquid chiller is cooling and the coolant temperature is lower than the preset stop intervention point, the liquid chiller is forced to enter the water circulation mode, and when the coolant temperature rises to the stop intervention point, the liquid chiller is controlled to enter the automatic mode.

2. The battery thermal management method according to claim 1, characterized in that, The cooling points of the liquid cooling system are dynamically updated based on the current ambient temperature and the maximum temperature of the battery cell, including: Determine the first cooling point based on the current ambient temperature; Determine the second cooling point based on the current maximum temperature of the battery cell; The lower of the first and second cooling points is selected as the updated cooling point of the liquid cooling system.

3. The battery thermal management method according to claim 1, characterized in that, Users can configure the liquid cooling strategy type by setting the liquid cooling strategy type parameter.

4. The battery thermal management method according to claim 1, characterized in that, When the coolant temperature rises to the stop intervention point, the steps for controlling the liquid chiller to enter automatic mode include: Determine whether the liquid chiller is currently in automatic mode; if so, maintain automatic mode; otherwise, after a delay of N seconds, control the liquid chiller to enter automatic mode; where N is a preset value.

5. The battery thermal management method according to claim 1, characterized in that, The battery thermal management system further includes: an air-cooling system; the air-cooling system includes fans corresponding to each battery module; the battery thermal management method further includes: The value of the cooling type parameter determines whether the user-set cooling type is air cooling or liquid cooling. When the user-set cooling type is air cooling, the air cooling system is activated for air cooling control; when the user-set cooling type is liquid cooling, the liquid cooling system is activated for liquid cooling control.

6. The battery thermal management method according to claim 5, characterized in that, The steps for starting the air-cooling system and controlling air cooling include cyclically executing the following steps for each battery module: Calculate the difference between the temperature of the battery module and the preset target temperature; Based on the interval where the difference is located and the preset correspondence between the interval where the difference is located and the fan speed level, the fan speed level corresponding to the difference is determined. The fan corresponding to the battery module is controlled to the determined fan speed level.

7. The battery thermal management method according to claim 6, characterized in that, The preset correspondence between the range of the difference and the fan speed setting includes: When the difference is greater than 4℃, the corresponding fan speed setting is the high speed setting; When the difference is greater than 2℃ and less than or equal to 4℃, the corresponding fan speed setting is medium speed. When the difference is less than or equal to 2℃, the corresponding fan speed setting is low speed.

8. A battery thermal management system, characterized in that, The liquid cooling system and the air cooling system further include a memory and a processor, the memory storing at least one program, the at least one program being executed by the processor to implement the steps of the battery thermal management method as described in any one of claims 1 to 7.

9. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the battery thermal management method as described in any one of claims 1 to 7.

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