Cooling control method of electric vehicle, cooling component and vehicle

Abstract

The present invention discloses a cooling control method, cooling assembly, and electric vehicle for an electric vehicle. The method comprises: determining whether a power battery meets cooling activation conditions based on ambient temperature and battery status information; if the power battery meets the cooling activation conditions, controlling the cooling assembly to operate so that the power battery enters a cooling mode; dynamically adjusting the cooling strategy of the cooling assembly based on changes in battery status information while in the cooling mode; and controlling the cooling assembly to exit the cooling mode if the power battery meets a cooling stop condition. The present invention comprehensively determines whether cooling should be activated based on ambient temperature and battery status information, and dynamically adjusts the cooling strategy based on changes in battery status after cooling is activated, thereby enabling early activation and precise control of power battery cooling, preventing a sharp rise in power battery temperature, accelerating charging efficiency, and extending battery life.

Description

Technical Field

[0001] The present invention relates to the technical field of battery cooling and temperature control, and in particular to a cooling control method, a cooling component and an electric vehicle. Background Art

[0002] With the rapid development of electric vehicle technology, the performance and safety of power batteries, as core components of electric vehicles, are receiving increasing attention. Existing cooling and temperature control methods for electric vehicle power batteries typically use a fixed temperature threshold to trigger cooling, while also maintaining a constant water temperature at the power battery cooling inlet. This approach can meet power battery cooling and temperature control requirements when the power battery is charging slowly and generating little heat.

[0003] However, as power batteries charge faster and generate more heat, existing cooling control methods can no longer fully meet the cooling and temperature control requirements. When a power battery is charged at a high rate with a relatively high current, cooling is activated after the battery reaches a fixed temperature threshold. This triggering of cooling is significantly delayed, causing the battery temperature to rise sharply, reaching the upper temperature limit for high-rate charging more quickly. This reduces the duration of high-rate charging, resulting in a limited increase in charging speed. Furthermore, when cooling is activated, the battery is cooled at a constant cooling inlet water temperature, which fails to suppress the temperature rise of the battery in the early stages of charging, thereby affecting charging speed. It also hinders the reduction of battery temperature differences and system energy consumption in the later stages of charging, impacting battery life and system energy consumption.

[0004] In view of this, it is necessary to provide a cooling control method that can meet the cooling requirements of power batteries under high-rate charging conditions. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a cooling control method for an automobile battery. The method comprehensively determines whether cooling needs to be turned on based on the ambient temperature and battery status information, and dynamically adjusts the cooling strategy according to the change of the battery status after cooling is turned on, so as to realize the early start and precise control of the power battery cooling, avoid the power battery temperature from rising sharply, thereby accelerating the charging efficiency of the power battery and extending the service life of the power battery, so that the temperature control capability of the power battery can meet the needs of high-rate charging.

[0006] The technical solution of the present invention provides a cooling control method for an automobile battery, comprising:

[0007] Determine whether the power battery meets the cooling start conditions based on the ambient temperature and battery status information;

[0008] If the power battery meets the cooling start condition, controlling the cooling component to operate so that the power battery enters a cooling mode;

[0009] Dynamically adjusting the cooling strategy of the cooling component according to changes in the battery status information in the cooling mode;

[0010] If the power battery meets the cooling stop condition, the cooling component is controlled to operate so that the power battery exits the cooling mode.

[0011] In one of the optional technical solutions, the determining whether the power battery meets the cooling start-up condition based on the ambient temperature and battery status information includes:

[0012] If the power battery is in a charging state, test the power battery;

[0013] The charging current value, maximum cell temperature value, minimum cell temperature value and cooling inlet water temperature value of the power battery are measured respectively and combined to generate battery status information;

[0014] If the maximum battery cell temperature is greater than or equal to a first temperature threshold, it is determined that the power battery meets the cooling start condition;

[0015] If the charging current value is continuously greater than or equal to the charging current threshold within a preset time, and the lowest battery cell temperature value is greater than or equal to a second temperature threshold, it is determined that the power battery meets the cooling start-up condition.

[0016] In one of the optional technical solutions, the charging current threshold is calculated by using the difference between the maximum battery cell temperature value and the reference temperature value, the difference between the ambient temperature and the reference temperature value, and characteristic parameters of the power battery.

[0017] In one of the optional technical solutions, the determining whether the power battery meets the cooling start-up condition based on the ambient temperature and battery status information further includes:

[0018] The temperature value of each battery cell is collected at intervals within a preset time, and the heating rate of each battery cell is calculated;

[0019] Calculating a temperature change trend of the power battery based on the charging current value and the temperature rise rate;

[0020] If the temperature change trend meets the rapid temperature rise condition, it is determined that the power battery meets the cooling start-up condition.

[0021] In one of the optional technical solutions, controlling the cooling component to operate so that the power battery enters a cooling mode includes:

[0022] Calculating a target water temperature value according to the charging current value, the maximum battery core temperature value, the minimum battery core temperature value, and the ambient temperature;

[0023] Calculating the temperature difference between the cooling inlet water temperature and the target water temperature;

[0024] The cooling power of the cooling assembly is determined based on the temperature difference, and the power battery enters a cooling mode until the cooling inlet water temperature value is equal to the target water temperature value.

[0025] In one of the optional technical solutions, dynamically adjusting the cooling strategy of the cooling component according to the change of the battery status information in the cooling mode includes:

[0026] Calculating a maximum cell temperature difference value by using the maximum cell temperature value and the minimum cell temperature value, and determining whether the power battery meets a cell temperature difference excessive condition according to the maximum cell temperature difference value;

[0027] If the maximum temperature difference of the battery cells does not meet the condition that the battery cell temperature difference is too large, the target water temperature value is not changed;

[0028] If the maximum temperature difference of the battery cells meets the condition that the temperature difference of the battery cells is too large, the target water temperature value is adjusted based on the maximum temperature difference of the battery cells.

[0029] In one of the optional technical solutions, judging whether the power battery meets the condition of excessive cell temperature difference based on the maximum cell temperature difference includes:

[0030] If the maximum temperature difference of the battery cells is less than or equal to the first temperature difference threshold, it is determined that the power battery does not meet the condition of excessive temperature difference of the battery cells, and the target water temperature value is not changed;

[0031] If the maximum temperature difference of the battery cell is greater than the first temperature difference threshold and less than or equal to the second temperature difference threshold, it is determined that the power battery meets the condition of excessive temperature difference of the battery cell, and a temperature compensation value is calculated according to the maximum temperature difference of the battery cell to be added to the target water temperature value;

[0032] If the maximum temperature difference of the battery cells is greater than the second temperature difference threshold, it is determined that the power battery meets the condition of excessive temperature difference of the battery cells, and the target water temperature is adjusted to the maximum cooling water temperature allowed by the cooling component.

[0033] In one of the optional technical solutions, if the power battery meets the cooling stop condition, controlling the cooling assembly to operate so that the power battery exits the cooling mode includes:

[0034] If the charging current value is continuously less than the charging current threshold within a preset time, and the maximum battery cell temperature value is less than or equal to a third temperature threshold, it is determined that the power battery meets the cooling stop condition.

[0035] The technical solution of the present invention provides a cooling component for implementing any of the aforementioned cooling control methods for automobile batteries, including a refrigeration circuit and a heat exchange circuit connected to the power battery, the refrigeration circuit and the heat exchange circuit are connected through a battery cooler, the refrigeration circuit includes a compressor, a condenser, a condenser fan, a battery cooler, an electronic expansion valve and a temperature and pressure sensor, and the heat exchange circuit includes an electronic water pump and a water temperature sensor.

[0036] The technical solution of the present invention provides an automobile, including an automobile body, in which the aforementioned cooling component is provided, and the cooling component can implement any step of the aforementioned automobile battery cooling control method.

[0037] The above technical solution has the following beneficial effects:

[0038] The cooling control method of the electric vehicle provided by the present invention comprehensively judges whether it is necessary to turn on cooling through the ambient temperature and battery status information, and dynamically adjusts the cooling strategy through the change of the battery status after the cooling is turned on, which can realize the early start of cooling of the power battery before the temperature is too high and realize precise control during the cooling process. When the power battery is in a high-rate charging state, the possible rapid temperature rise is predicted through multi-dimensional information to turn on the cooling temperature control in advance. In the cooling mode, the cooling strategy of the cooling component is dynamically adjusted according to the change of the battery status information to improve the cooling power and cooling accuracy. By performing cooling control on the power battery through the method of the present invention, energy waste caused by excessive cooling can be avoided through precise temperature control and dynamic adjustment of the cooling strategy, so as to improve the overall energy utilization efficiency of the electric vehicle, and can also effectively reduce the risk of thermal runaway of the power battery in a high-temperature environment, extend the service life of the power battery, and improve the safety and reliability of the electric vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The disclosure of the present invention will become more easily understood with reference to the accompanying drawings. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the drawings:

[0040] Figure 1 A flowchart of a cooling control method for an automobile battery provided in one embodiment of the present invention;

[0041] Figure 2 A flowchart of a cooling control method for an automobile battery provided in another embodiment of the present invention;

[0042] Figure 3 A flowchart of a cooling control method for an automobile battery provided in yet another embodiment of the present invention;

[0043] Figure 4A flowchart of a cooling control method for an automobile battery provided in yet another embodiment of the present invention;

[0044] Figure 5 A schematic structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0046] It should be noted that the automotive batteries mentioned below refer to the batteries that power vehicles such as electric vehicles and hybrid vehicles. Power batteries are also responsible for powering the high-voltage power systems of electric vehicles. Power batteries can store electrical energy and release it when needed, and can be recharged repeatedly. To meet the needs of long-distance vehicles, power batteries need to have a high energy density, that is, they can store more electrical energy per unit volume or weight. Among them, lithium-ion power batteries are generally used in electric vehicles. They store and release electrical energy through the migration of lithium ions between the positive and negative electrodes. They have the advantages of high energy density, long cycle life, and low self-discharge rate.

[0047] Power batteries typically consist of multiple cells, which are connected in series or parallel to form a battery module. Multiple battery modules are then combined into a battery pack, ultimately forming the entire power battery system. A cell is the smallest unit in a power battery, responsible for storing and releasing electrical energy. Each cell has specific performance metrics, such as voltage, capacity, and energy density. In a power battery, the performance of the cell directly affects the performance of the entire battery pack. During the charge and discharge process, the temperature and state of each cell vary.

[0048] High-rate charging of power batteries refers to the process of charging a power battery at a high current rate in a short period of time. This charging method is crucial for improving charging efficiency and shortening charging time, and is particularly suitable for applications requiring fast charging, such as electric vehicles. High-rate charging can charge a large amount of energy into a power battery in a relatively short period of time, significantly reducing charging time. This is crucial for improving user experience and increasing device efficiency. Batteries charged at high rates typically have high power output capabilities, enabling them to meet the operational requirements of devices with high power demands. High-rate charging places higher demands on battery thermal management and safety. Batteries can generate significant heat during rapid charging, requiring effective heat dissipation measures to prevent overheating. Furthermore, high-rate charging can exacerbate side reactions within the battery, impacting its cycle life and safety. High-rate charging of power batteries is an efficient and fast charging method, crucial for improving device efficiency and meeting high power demands. However, achieving high-rate charging requires overcoming a number of technical challenges. Therefore, it is necessary to optimize the cooling control of power batteries during high-rate charging.

[0049] like Figure 1 A cooling control method for a vehicle battery provided by one embodiment of the present invention includes:

[0050] Step S101: judging whether the power battery meets the cooling start condition according to the ambient temperature and battery status information.

[0051] Step S102: If the power battery meets the cooling start condition, control the cooling component to operate so that the power battery enters a cooling mode.

[0052] Step S103: dynamically adjusting the cooling strategy of the cooling component according to the change of the battery status information in the cooling mode.

[0053] Step S104: If the power battery meets the cooling stop condition, control the cooling assembly to operate so that the power battery exits the cooling mode.

[0054] Specifically, unlike conventional cooling activation, which relies solely on whether the current power battery temperature is greater than a preset value, step S101 of this embodiment also references the ambient temperature and power battery status information. This battery status information can include multiple real-time power battery operating parameters, such as charging voltage, charging current, charging time, and cell temperature. By comprehensively considering ambient temperature and battery status information, the cooling needs of the power battery can be accurately determined. Compared to conventional cooling activation based on a single temperature threshold, the comprehensive assessment method provided by this embodiment is more adaptable to high-rate charging conditions with complex and variable operating conditions, ensuring battery safety while optimizing energy efficiency. It can also predict in advance whether the power battery will overheat if continued charging in its current state.

[0055] Step S102 controls the operation of the cooling assembly to put the power battery into cooling mode. As an example, the cooling assembly includes a refrigeration circuit and a heat exchange circuit connected to the power battery. The refrigeration circuit and the heat exchange circuit are connected through a battery cooler. The main function of the refrigeration circuit is to evaporate the internal refrigerant in the battery cooler to absorb heat to achieve cooling. It generally includes a compressor, condenser, condenser fan, battery cooler, electronic expansion valve and temperature and pressure sensor, and absorbs the heat of the coolant in the heat exchange circuit through the battery cooler. The heat exchange circuit includes an electronic water pump and a water temperature sensor. The water temperature sensor is set at the coolant inlet of the power battery to measure the water temperature of the cooling inlet of the power battery. The cooling inlet mentioned below refers to the port on the power battery for the coolant to enter. In actual use, the coolant in the heat exchange circuit can be a 50% by volume ethylene glycol water solution. Therefore, the water temperature mentioned below refers to the temperature of the coolant in the heat exchange circuit.

[0056] Step S103 takes into account the significant differences in cooling requirements for power batteries under different environmental conditions, such as high or low temperatures, or large cell temperature differences, as well as in different charging states, such as fast charging, slow charging, or static state. Therefore, this embodiment detects the dynamic changes in ambient temperature and battery status information in real time, accurately determining when to activate the cooling system, the cooling time, and the cooling temperature. In other words, it controls the cooling strategy of the cooling component to prevent the cooling component from intervening in the power battery cooling too early or too late, thereby reducing energy waste and effectively extending battery life. By dynamically adjusting the cooling strategy, it is possible to ensure that the power battery adopts a reasonable cooling strategy in various charging and discharging scenarios. In particular, by pre-implementing highly efficient cooling behavior in high-rate charging states, it is possible to avoid situations where the power battery temperature is too high and high-rate charging cannot be continued, significantly improving the continuity and safety of high-rate charging of the power battery.

[0057] Step S104 determines whether the power battery meets the cooling stop conditions. When the power battery meets the corresponding conditions, ensuring that the power battery can continue to charge at a high rate for a period of time, the main control module controls the operation of the cooling assembly to cause the power battery to exit the cooling mode, thereby preventing battery overcooling and energy waste. While improving the continuity and safety of high-rate charging of the power battery, it also saves energy, thereby avoiding a significant reduction in the vehicle's endurance due to the cooling control method provided by the present invention.

[0058] Through the above steps, the cooling timing of the power battery can be accurately predicted, the response speed and accuracy of the cooling component are improved, and the power battery performance degradation and safety hazards caused by overheating are effectively reduced, while also optimizing the energy utilization efficiency of the entire vehicle.

[0059] In summary, the electric vehicle cooling control method provided in this embodiment comprehensively determines whether cooling is necessary based on ambient temperature and battery status information. Once cooling is enabled, the cooling strategy is dynamically adjusted based on changes in battery status. This enables cooling of the power battery to be initiated before the battery temperature reaches excessively high temperatures, allowing for precise control during the cooling process. When the power battery is in a high-rate charging state, multi-dimensional information is used to predict the potential for rapid temperature increases, enabling cooling temperature control to be initiated in advance. In cooling mode, the cooling strategy of the cooling assembly is dynamically adjusted based on changes in battery status information, improving cooling power and accuracy.

[0060] In addition, by controlling the cooling of the power battery through the method of the present invention, unnecessary energy waste can be avoided through precise temperature control and dynamic adjustment of the cooling strategy, so as to improve the overall energy utilization efficiency of the electric vehicle. It can also effectively reduce the risk of thermal runaway of the power battery in a high-temperature environment, minimize the overheating time of the power battery in a high-rate charging state, extend the service life of the power battery, and improve the safety and reliability of the electric vehicle.

[0061] In one embodiment, Figure 2 As shown, step S101 includes:

[0062] Step S201: If the power battery is in a charging state, the power battery is tested.

[0063] Step S202: the charging current value, the maximum battery cell temperature value, the minimum battery cell temperature value and the cooling inlet water temperature value of the power battery are measured respectively and combined to generate battery status information.

[0064] Step S203: If the maximum battery cell temperature value is greater than or equal to the first temperature threshold, it is determined that the power battery meets the cooling start condition.

[0065] Step S204: If the charging current value is continuously greater than or equal to the charging current threshold within a preset time, and the lowest battery cell temperature value is greater than or equal to a second temperature threshold, it is determined that the power battery meets the cooling start-up condition.

[0066] In this embodiment, the temperature of each cell in the power battery is measured separately, and the highest and lowest cell temperatures are selected as the maximum and minimum cell temperatures, respectively. In step S203, by determining whether the highest cell temperature is greater than or equal to a first temperature threshold, it is possible to determine whether the power battery has partially overheated or is showing a tendency to overheat. Furthermore, it can be determined that the power battery meets the cooling activation conditions and that the current power battery needs to be cooled.

[0067] In step S204, if the maximum cell temperature is less than the first temperature threshold, but the charging current value is continuously greater than or equal to the charging current threshold, the preferred duration is 10 seconds to avoid misjudgment caused by a momentary increase in the charging current. If this condition is met, it can be determined that the power battery is in a high-rate charging state. At this time, it is necessary to further determine whether the power battery has a tendency to overheat and ensure that the minimum cell temperature is greater than or equal to the second temperature threshold to prevent the temperature of some cells in the power battery from being too low after cooling is turned on. If both the charging current value and the minimum cell temperature meet the conditions, it can be determined that the power battery meets the cooling turn-on conditions and the current power battery needs to be cooled.

[0068] Furthermore, the charging current threshold is calculated as follows:

[0069] I v =I p -α1(T max -T)-β1(T amb -T)

[0070] Among them, I v is the charging current threshold, I p is the reference current value, α1 is the first temperature coefficient, β1 is the second temperature coefficient, T max is the maximum cell temperature, T amb is the ambient temperature, and T is the reference temperature. p , α1, β1 and T are fixed values ​​obtained based on the characteristics and calibration of the power battery and cooling components. The designer can also change I p , α1, β1 and T values, as an example, I p is 250A, α1 is 6, β1 is 3, and T is 25.

[0071] This embodiment improves the flexibility and accuracy of setting the charging current threshold, thereby avoiding safety hazards caused by low charging efficiency due to a single fixed threshold or incorrectly triggering cooling in extreme environments, thereby further ensuring the safety and stability of the power battery.

[0072] In one embodiment, the charging current threshold is obtained by calculating the difference between the maximum battery cell temperature value and a reference temperature value, the difference between the ambient temperature and the reference temperature value, and characteristic parameters of the power battery.

[0073] In this embodiment, the charging current threshold is determined through dynamic calculation, taking into account the difference between the maximum cell temperature and the reference temperature, the difference between the ambient temperature and the reference temperature, and the inherent characteristics of the power battery, such as heat capacity and thermal resistance. This dynamic adjustment mechanism, based on real-time data and battery characteristics, makes the setting of the charging current threshold more scientific and reasonable.

[0074] Batteries' thermal response characteristics vary under different temperature environments. By introducing the relative difference between the baseline temperature and the cell temperature and environment, combined with the physical properties of the battery itself, the rate of heat accumulation during charging can be more accurately assessed, allowing for the development of more appropriate current limit standards to ensure battery operation within a safe range.

[0075] In one embodiment, Figure 2 As shown, step S101 also includes:

[0076] Step S205: collecting the temperature value of each battery cell at intervals within a preset time, and calculating the temperature rise rate of each battery cell.

[0077] Step S206: Calculating a temperature change trend of the power battery based on the charging current value and the temperature rise rate.

[0078] Step S207: If the temperature change trend meets the rapid temperature rise condition, it is determined that the power battery meets the cooling start condition.

[0079] In this embodiment, by collecting cell temperature values ​​at preset intervals and calculating the temperature rise rate, combined with the charging current value, a thermal model is used to predict the future temperature trend of the power battery. This prediction method combines the advantages of real-time monitoring and model prediction, enabling early detection of potential overheating risks.

[0080] During charging, the battery's temperature gradually rises due to internal chemical reactions and resistance heat generation. By monitoring and calculating the temperature rise rate in real time, combined with the key factor of charging current, we can more accurately predict the battery's future temperature state, providing a scientific basis for timely activation of the cooling system.

[0081] This embodiment achieves the effect of predicting the temperature change trend of the power battery in advance, provides sufficient time for the cooling execution of the cooling component, and effectively reduces the risk of power battery damage caused by sudden temperature rise.

[0082] In one embodiment, Figure 3 As shown, step S102 includes:

[0083] Step S301: Calculating a target water temperature value according to the charging current value, the maximum battery core temperature value, the minimum battery core temperature value, and the ambient temperature.

[0084] Step S302: Calculate the temperature difference between the cooling inlet water temperature and the target water temperature.

[0085] Step S303: determining the cooling power of the cooling assembly based on the temperature difference, and causing the power battery to enter a cooling mode until the cooling inlet water temperature value is equal to the target water temperature value.

[0086] In this embodiment, an algorithm calculates a target water temperature that effectively balances battery cooling requirements with cooling system energy consumption, using parameters such as charging current, maximum and minimum cell temperatures, and ambient temperature. Subsequently, by monitoring the deviation between the cooling inlet water temperature and the target temperature, the operating state of the cooling assembly, including the electronic expansion valve opening, electronic water pump speed, and coolant flow rate, is dynamically adjusted to precisely control the cooling inlet water temperature toward the target temperature within a preset timeframe.

[0087] Setting the target water temperature requires a comprehensive consideration of both battery heat dissipation requirements and cooling system efficiency. Excessively high water temperatures can lead to poor cooling performance, while excessively low temperatures increase cooling system energy consumption. Therefore, calculating the optimal target water temperature through an algorithm and adjusting the cooling system's operating state accordingly are key to achieving efficient cooling.

[0088] Specifically, the target water temperature value is calculated as follows:

[0089] T w =T p -α2(T max -T)-β2(T amb -T)

[0090] Among them, T w is the target water temperature, T p is the reference temperature value, α2 is the third temperature coefficient, β2 is the fourth temperature coefficient, T max is the maximum cell temperature, T amb is the ambient temperature, and T is the reference temperature. p, α2, β2 and T are fixed values ​​obtained based on the characteristics and calibration of the power battery and cooling components. The designer can also change I p , α2, β2 and T values, as an example, T p is 15℃, α2 is 0.2, β2 is 0.1, and T is 25.

[0091] By comprehensively calculating the target water temperature value based on multiple parameters, the control accuracy and efficiency of the cooling system can be improved to ensure that the power battery always remains within a safe and efficient temperature range during the charging process, while reducing the energy consumption of the cooling system.

[0092] In one embodiment, Figure 4 As shown, step S103 includes:

[0093] Step S401: calculating a maximum cell temperature difference value through the maximum cell temperature value and the minimum cell temperature value, and judging whether the power battery meets a cell temperature difference excessive condition according to the maximum cell temperature difference value.

[0094] If the maximum battery cell temperature difference does not meet the battery cell temperature difference excessive condition, the target water temperature value is not changed.

[0095] If the maximum temperature difference of the battery cells meets the condition that the temperature difference of the battery cells is too large, the target water temperature value is adjusted based on the maximum temperature difference of the battery cells.

[0096] In this embodiment, the uniformity of the temperature distribution within the battery can be assessed by monitoring and calculating the maximum temperature difference between the battery cells. When the maximum temperature difference exceeds a preset threshold, it indicates that there may be local overheating within the battery. In this case, the target water temperature should be adjusted based on the temperature difference to optimize the heat dissipation effect.

[0097] Temperature uniformity within the battery has a significant impact on its performance and lifespan. Localized overheating not only degrades battery performance but can also lead to safety incidents. Therefore, dynamically adjusting the target water temperature to address large temperature differences within the battery cells is a crucial measure to ensure safe and stable battery operation.

[0098] The cooling system's ability to regulate the temperature distribution within the battery has been enhanced, effectively reducing the temperature difference between cells and improving the overall performance and life of the battery. At the same time, it also further improves the reliability and safety of the power battery under complex operating conditions.

[0099] Furthermore, after step S401, the following steps are included:

[0100] Step S402: If the maximum temperature difference of the battery cells is less than or equal to the first temperature difference threshold, it is determined that the power battery does not meet the condition of excessive temperature difference of the battery cells, and the target water temperature value is not changed.

[0101] Step S403: If the maximum temperature difference of the battery cell is greater than the first temperature difference threshold and less than or equal to the second temperature difference threshold, it is determined that the power battery meets the condition of excessive temperature difference of the battery cell, and a temperature compensation value is calculated according to the maximum temperature difference of the battery cell to be added to the target water temperature value.

[0102] Step S404: If the maximum temperature difference of the battery cells is greater than the second temperature difference threshold, it is determined that the power battery meets the condition of excessive temperature difference of the battery cells, and the target water temperature is adjusted to the maximum cooling water temperature allowed by the cooling component.

[0103] As a preferred method, the maximum temperature difference of the battery cell is calculated as follows:

[0104] T diff =T max -T min

[0105] Among them, T diff is the maximum temperature difference of the battery cell, T max is the maximum cell temperature, T min is the minimum cell temperature.

[0106] The temperature compensation value is calculated as:

[0107] T a =K*T diff

[0108] Among them, T a is the temperature compensation value, and K is the compensation coefficient obtained according to the calibration of the power battery or cooling component.

[0109] The target water temperature value is adjusted as follows:

[0110] T c =T w +T a

[0111] Among them, T c is the cooling water inlet temperature, T w is the target water temperature.

[0112] In this embodiment, the present invention proposes two adjustment strategies for situations where the temperature difference between battery cells is too large. When the maximum temperature difference between battery cells is between the first and second temperature difference thresholds, a temperature compensation method is used. The temperature compensation value is calculated based on the power battery characteristics and the maximum temperature difference between battery cells, taking into account factors such as the temperature difference, battery thermal capacity, and cooling system response speed. The goal is to gradually reduce the temperature difference between battery cells by fine-tuning the target water temperature.

[0113] When the maximum temperature difference between the battery cells exceeds the second temperature difference threshold, the system will take more aggressive measures and directly set the target water temperature to the maximum cooling water temperature allowed by the cooling assembly. This will maximize cooling power, quickly reduce battery temperature, and prevent further overheating. After the maximum cooling water temperature value persists for a period of time, such as 2 minutes, the system will re-evaluate whether the maximum temperature difference between the battery cells is less than or equal to the second temperature difference threshold. If the condition is met, the excessive battery temperature difference flag is cleared and the temperature difference is re-evaluated. If the condition is not met, the excessive battery temperature difference flag will continue to be issued, and cooling will continue at the maximum cooling water temperature allowed by the cooling assembly as the cooling inlet water temperature value.

[0114] Excessive temperature differences in battery cells are a major challenge in battery thermal management. Too small an adjustment may not effectively improve the temperature distribution, while too large an adjustment may waste energy or cause other problems. Therefore, the present invention achieves precise control of battery cell temperature differences by introducing two strategies: temperature compensation value and maximum cooling water temperature value. The temperature compensation value strategy is suitable for situations with small temperature differences and can reduce energy consumption while ensuring efficiency. The maximum cooling water temperature value strategy is suitable for emergency situations with extremely large temperature differences and can quickly reduce the battery temperature to ensure battery safety.

[0115] This dynamic adjustment strategy not only improves the cooling system's flexibility and responsiveness, but also ensures optimal cooling under varying temperature conditions. It effectively reduces temperature differences between cells, improving overall battery performance and lifespan, while also enhancing the safety and reliability of power batteries under extreme operating conditions.

[0116] In one embodiment, step S104 includes:

[0117] If the charging current value is continuously less than the charging current threshold within the preset time, and the maximum battery cell temperature value is less than or equal to the third temperature threshold, it is determined that the power battery meets the cooling stop condition.

[0118] In this embodiment, a temperature detection interval is pre-set. After a period of cooling activation, it is determined whether the power battery meets the cooling stop condition. This prevents continued cooling from wasting energy and preventing the power battery from overly low temperature. The third temperature threshold is a system-preset value or is calculated based on a predicted temperature rise of the power battery during high-rate charging. If the charging current value remains below the charging current threshold for a predetermined period of time, for example, 10 seconds, it indicates that the power battery has exited the high-rate charging state. A determination is then made as to whether the maximum cell temperature value is less than or equal to the third temperature threshold. If all conditions are met simultaneously, it can be determined that the power battery temperature is no longer suitable for high-rate charging and that the cell temperature is within a safe range for normal operation. The cooling assembly does not need to be activated during the next temperature detection interval. At this point, the cooling assembly can be controlled to stop operating or operate at low power, causing the power battery to exit cooling mode.

[0119] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0120] One embodiment of the present invention provides a cooling component for implementing the cooling control method of an automobile battery of any of the aforementioned embodiments. The cooling component includes a refrigeration circuit and a heat exchange circuit connected to the power battery. The refrigeration circuit and the heat exchange circuit are connected through a battery cooler. The refrigeration circuit includes a compressor, a condenser, a condenser fan, a battery cooler, an electronic expansion valve and a temperature and pressure sensor. The heat exchange circuit includes an electronic water pump and a water temperature sensor.

[0121] An embodiment of the present invention provides a car, including a car body, in which a cooling assembly as described in the above embodiments is provided. The cooling assembly can implement all steps of the cooling control method for a car battery in any of the above embodiments.

[0122] like Figure 5 The figure shows a hardware structure diagram of an electronic device of the present invention, including a memory 502, a processor 501 and an electronic device program on the memory 502. The processor 501 executes the electronic device program to implement the steps of the automotive battery cooling control method of any of the above embodiments.

[0123] Figure 5 A processor 501 is taken as an example.

[0124] The electronic device may further include an input device 503 and a display device 504 .

[0125] The processor 501, the memory 502, the input device 503 and the display device 504 may be connected via a bus or other means, with the bus connection being used as an example in the figure.

[0126] Memory 502, as a non-volatile electronic device-readable storage medium, can be used to store non-volatile software programs, non-volatile electronic device executable programs, and modules, such as the program instructions / modules corresponding to the automotive battery cooling control method in the embodiments of this application. Processor 501 executes the non-volatile software programs, instructions, and modules stored in memory 502 to perform various functional applications and data processing, thereby implementing the automotive battery cooling control method in the aforementioned embodiments.

[0127] Memory 502 may include a program storage area and a data storage area. The program storage area may store an operating system and application programs required for at least one function; the data storage area may store data generated based on the use of the automotive battery cooling control method. Furthermore, memory 502 may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state memory device. In some embodiments, memory 502 may optionally include memory remotely located relative to processor 501. Such remote memory may be connected to the apparatus executing the automotive battery cooling control method via a network. Examples of such networks include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0128] The input device 503 may receive a user click input and generate a signal input related to the user setting and function control of the cooling control method of the vehicle battery. The display device 504 may include a display device such as a display screen.

[0129] The one or more modules are stored in the memory 502 and, when executed by the one or more processors 501 , execute the cooling control method for a vehicle battery in any of the above method embodiments.

[0130] When in operation, the electronic device disclosed in the present invention can execute all steps of the above-mentioned automotive battery cooling control method, comprehensively determine whether cooling needs to be turned on based on ambient temperature and battery status information, and dynamically adjust the cooling strategy based on changes in battery status after cooling is turned on, so as to achieve early start and precise control of power battery cooling, avoid a sharp rise in power battery temperature, accelerate the charging efficiency of the power battery, extend the service life of the power battery, and enable the temperature control capability of the power battery to meet the needs of high-rate charging.

[0131] An embodiment of the present invention provides an electronic device readable storage medium storing an electronic device program / instruction. When the electronic device program / instruction is executed by the processor 501, all steps of the above-mentioned vehicle battery cooling control method are implemented.

[0132] In the context of the present disclosure, a storage medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or apparatus. The storage medium may be a machine-readable signal medium or a machine-readable storage medium. Alternatively, the storage medium may be a non-transitory electronic device readable storage medium, for example, a non-transitory electronic device readable storage medium may be a ROM, a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, and an optical data storage device.

[0133] An embodiment of the present invention provides an electronic device program product, including an electronic device program / instruction. When the electronic device program / instruction is executed by a processor, the steps of the above-mentioned vehicle battery cooling control method are implemented.

[0134] By running the above-mentioned electronic device program product, all steps of the automotive battery cooling control method described above can be executed, and whether cooling needs to be turned on can be comprehensively judged based on the ambient temperature and battery status information. After cooling is turned on, the cooling strategy can be dynamically adjusted based on the change in battery status to achieve early start and precise control of power battery cooling, avoid a sharp rise in power battery temperature, accelerate the charging efficiency of the power battery, extend the service life of the power battery, and enable the temperature control capability of the power battery to meet the needs of high-rate charging.

[0135] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A cooling control method for a vehicle battery, characterized in that: include: Determine whether the power battery meets the cooling start conditions based on the ambient temperature and battery status information; If the power battery is in a charging state, test the power battery; If the power battery meets the cooling start condition, controlling the cooling component to operate so that the power battery enters a cooling mode; Dynamically adjusting the cooling strategy of the cooling component according to the change of the battery status information in the cooling mode specifically includes: Calculate the maximum temperature difference of the battery cells by the maximum battery cell temperature value and the minimum battery cell temperature value, and determine whether the power battery meets the battery cell temperature difference excessive condition according to the maximum battery cell temperature difference value; If the maximum temperature difference of the battery cells does not meet the condition that the battery cell temperature difference is too large, the target water temperature value is not changed; If the maximum temperature difference of the battery cells meets the condition that the temperature difference of the battery cells is too large, adjusting the target water temperature value based on the maximum temperature difference of the battery cells; If the power battery meets the cooling stop condition, the cooling component is controlled to operate so that the power battery exits the cooling mode.

2. The cooling control method for a vehicle battery according to claim 1, characterized in that: The determining whether the power battery meets the cooling start condition according to the ambient temperature and battery status information includes: The charging current value, maximum cell temperature value, minimum cell temperature value and cooling inlet water temperature value of the power battery are measured respectively and combined to generate battery status information; If the maximum battery cell temperature is greater than or equal to a first temperature threshold, it is determined that the power battery meets the cooling start condition; If the charging current value is continuously greater than or equal to the charging current threshold within a preset time, and the lowest battery cell temperature value is greater than or equal to a second temperature threshold, it is determined that the power battery meets the cooling start-up condition.

3. The cooling control method for an automobile battery according to claim 2, wherein: The charging current threshold is obtained by calculating the difference between the maximum battery cell temperature value and the reference temperature value, the difference between the ambient temperature and the reference temperature value, and the characteristic parameters of the power battery.

4. The cooling control method for a vehicle battery according to claim 2, wherein: The determining whether the power battery meets the cooling start-up condition according to the ambient temperature and the battery status information further includes: The temperature value of each battery cell is collected at intervals within a preset time, and the heating rate of each battery cell is calculated; Calculating a temperature change trend of the power battery based on the charging current value and the temperature rise rate; If the temperature change trend meets the rapid temperature rise condition, it is determined that the power battery meets the cooling start-up condition.

5. The cooling control method for a vehicle battery according to claim 2, characterized in that: The controlling the cooling component to operate so that the power battery enters a cooling mode includes: Calculating a target water temperature value according to the charging current value, the maximum battery core temperature value, the minimum battery core temperature value, and the ambient temperature; Calculating the temperature difference between the cooling inlet water temperature and the target water temperature; The cooling power of the cooling assembly is determined based on the temperature difference, and the power battery enters a cooling mode until the cooling inlet water temperature value is equal to the target water temperature value.

6. The cooling control method for a vehicle battery according to claim 5, characterized in that: The determining whether the power battery meets the condition of excessive cell temperature difference according to the maximum cell temperature difference includes: If the maximum temperature difference of the battery cells is less than or equal to the first temperature difference threshold, it is determined that the power battery does not meet the condition of excessive temperature difference of the battery cells, and the target water temperature value is not changed; If the maximum temperature difference of the battery cell is greater than the first temperature difference threshold and less than or equal to the second temperature difference threshold, it is determined that the power battery meets the condition of excessive temperature difference of the battery cell, and a temperature compensation value is calculated according to the maximum temperature difference of the battery cell to be added to the target water temperature value; If the maximum temperature difference of the battery cells is greater than the second temperature difference threshold, it is determined that the power battery meets the condition of excessive temperature difference of the battery cells, and the target water temperature is adjusted to the maximum cooling water temperature allowed by the cooling component.

7. The cooling control method for a vehicle battery according to claim 2, characterized in that: If the power battery meets the cooling stop condition, controlling the cooling component to operate so that the power battery exits the cooling mode includes: If the charging current value is continuously less than the charging current threshold within a preset time, and the maximum battery cell temperature value is less than or equal to a third temperature threshold, it is determined that the power battery meets the cooling stop condition.

8. A cooling assembly for implementing the cooling control method for an automobile battery according to any one of claims 1 to 7, characterized in that: It includes a refrigeration circuit and a heat exchange circuit connected to the power battery. The refrigeration circuit and the heat exchange circuit are connected through a battery cooler. The refrigeration circuit includes a compressor, a condenser, a condenser fan, a battery cooler, an electronic expansion valve and a temperature and pressure sensor. The heat exchange circuit includes an electronic water pump and a water temperature sensor.

9. A car, comprising a car body, characterized in that: The automobile body is provided with a cooling assembly as claimed in claim 8, and the cooling assembly can implement the steps of the cooling control method for the automobile battery as claimed in any one of claims 1 to 7.

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