Rapid heat balance test method for power battery system

Abstract

The invention discloses a rapid heat balance test method for a power battery system, and relates to the technical field of heat balance test, and the method comprises the following steps: carrying out the preliminary evaluation of the current heat balance state of the power battery system, and setting a reasonable preset temperature value; under a preset temperature value, executing a discharge test item of the power battery system; the temperature difference between the temperature measuring points is calculated, and power reduction processing is carried out on the discharge power; after the discharging test and adjustment are completed, a charging test item of the power battery system is executed; and analyzing the current heat balance state of the power battery system. The test method relates to multiple links of temperature monitoring, discharging test, temperature difference judgment, power adjustment, charging test and the like, the heat balance performance of the power battery system in the charging and discharging process can be comprehensively evaluated conveniently, the heat balance performance can be improved by reducing power and adjusting the preset temperature value, and the service life of the power battery system is prolonged. And therefore, the temperature change of the power battery in the charging and discharging process is always in a safe range.

Description

Technical Field

[0001] The invention relates to the technical field of thermal balance testing, and in particular to a method for rapid thermal balance testing of a power battery system. Background Art

[0002] As the core component of electric vehicles, the performance stability and safety of the power battery system are directly related to the operating efficiency of the entire vehicle and the safety of passengers. When charging and discharging, the power battery system will release heat, and the heat dissipation effect of the power battery system is poor, so a certain amount of heat will accumulate inside the battery pack. In the above case, it is easy to trigger the upper limit of the protection temperature, causing the power battery system to be unable to continue to operate. Therefore, before the electric vehicle leaves the factory, it is necessary to test the thermal balance performance of its power battery system to ensure that the temperature change of the power battery during the charging and discharging process is within a safe range.

[0003] Based on this, a method for rapid testing the thermal balance of a power battery system is now provided, which can eliminate the drawbacks of the existing technical solutions. Summary of the invention

[0004] The purpose of the present invention is to provide a method for quickly testing the thermal balance of a power battery system to solve the problem in the background technology that the power battery system is easily triggered to the upper limit of the protection temperature during charging and discharging, so that the thermal balance performance of the electric vehicle needs to be tested before it leaves the factory.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for quickly testing the thermal balance of a power battery system comprises the following steps:

[0007] S1. Conduct a preliminary assessment of the current thermal balance state of the power battery system and set a reasonable preset temperature value based on the design specifications and working environment requirements of the power battery system;

[0008] S2. At the preset temperature value, simulate the load conditions in actual use, perform the discharge test items of the power battery system, and continuously monitor and record the temperature changes of each temperature measuring point during the discharge process;

[0009] S3, calculating the temperature difference between each temperature measurement point, if the temperature difference exceeds the preset range, reducing the discharge power, after the discharge test and the power reduction process, adjusting the preset temperature value according to the actual temperature change of the battery;

[0010] S4. After completing the discharge test and adjustment, simulate the charging conditions in actual use, perform the charging test items of the power battery system, and continuously monitor and record the temperature changes of the battery during the charging process;

[0011] S5. Analyze the current thermal equilibrium state of the power battery system based on the above test data and parameters.

[0012] Preferably, the step S1 comprises:

[0013] S11. Measure the temperature of each single cell in the battery pack to see whether its distribution is uniform, and monitor the temperature changes of each temperature measuring point in the battery pack over a period of time. If the temperature distribution is quite different, it indicates that the parameters inside the power battery system need to be adjusted and optimized.

[0014] S12. According to the optimal operating temperature range of the battery pack, select an intermediate value as the preset temperature value. This temperature value will be used for environmental control and result comparison in subsequent tests.

[0015] Preferably, the step S2 comprises:

[0016] S21. After confirming that all safety measures are in place, ensure that the voltage and current parameters of the battery pack are within the monitoring range and meet the test standards during the discharge process under the preset temperature value environment, and then discharge the battery pack according to the standard discharge procedure;

[0017] S22. Use high-precision testing equipment and data analysis equipment to continuously monitor and record the temperature changes at each temperature measuring point during the discharge process. The temperature measuring points should cover all key areas of the battery pack, including but not limited to battery cells, connections between modules, and heat sinks.

[0018] Preferably, step S3 comprises:

[0019] S31. After the power battery system executes each discharge test item, determine whether the difference between the current temperature value of the power battery system and the preset temperature value is within a preset range;

[0020] S32, calculating the temperature difference between each temperature measurement point, if the difference between the current temperature value of the power battery system and the preset temperature value is not within the preset range, reducing the discharge power of the current discharge test item;

[0021] S33, if the difference between the current temperature value of the power battery system and the preset temperature value is still not within the preset range after the power reduction process, the discharge power of the current discharge test item is reduced again until the difference between the current temperature value of the power battery system and the preset temperature value is within the preset range;

[0022] S34. If the discharge power of the power battery system still does not meet the preset condition after the power reduction process, adjust the preset temperature value;

[0023] The temperature difference judgment formula is used to determine whether the temperature difference inside the battery system is within the allowable range, and the power adjustment formula is used to adjust the discharge power. The corresponding formula is as follows:

[0024] ΔT=|T measured -T reference |

[0025] P adjusted =P initial ·(1-α·ΔT)

[0026] Where ΔT represents the temperature difference, T measured Indicates the actual measured temperature, T reference Indicates the preset temperature reference value, P adjusted Represents the adjusted discharge power, P initial represents the initial discharge power, and α is the adjustment coefficient.

[0027] Preferably, step S4 comprises:

[0028] S41. After the discharge test is completed and the temperature is restored to the preset value, confirm that all safety measures are in place and the charging equipment is correctly connected, and then charge the battery pack according to the standard charging procedures to ensure that the voltage and current parameters of the battery pack are within the monitoring range during the charging process and meet the test standards;

[0029] S42. Use high-precision testing equipment and data analysis equipment to continuously monitor and record the temperature changes at each temperature measuring point during the charging process. The temperature measuring points should cover all key areas of the battery pack.

[0030] Preferably, the thermal equilibrium state in step S5 is analyzed using a thermal equilibrium equation, and the thermal equilibrium equation is as follows:

[0031] Q a +Q e =c·m·(T measured -T0)+k·S·(T measured -T env )

[0032] Among them, Q a Indicates the heat generated inside the battery pack, Q e represents the input heat from the outside of the battery pack, c represents the specific heat capacity of the battery, m represents the mass of the battery, T0 represents the initial temperature of the battery, k represents the heat dissipation coefficient between the battery and the environment, S represents the heat dissipation area of ​​the battery, and T env Indicates the ambient temperature.

[0033] Preferably, a thermal balance rapid testing system for a power battery system is also included, the testing system comprising:

[0034] A network database is used to collect, store and provide historical data and big data information of thermal balance of power battery system, and divide the data in the corresponding information into several groups according to time, temperature and charge and discharge state parameters;

[0035] The test device is used to monitor and collect the temperature of each temperature measurement point of the power battery system and the flow parameters of the battery pack coolant in real time;

[0036] A data analysis device, used to collect test device data and evaluate the thermal balance state of the battery pack through data processing and data analysis operations;

[0037] The processor is used to receive and output the information results of each module and the network database, and to control various information and output coordination instructions.

[0038] Preferably, the testing device includes a plurality of temperature sensors and flow sensors. The temperature sensor is used to monitor the temperature changes at multiple temperature measuring points of the battery, and the flow sensor is used to monitor the coolant flow changes at multiple key areas of the battery in real time. One side of the sensor is provided with a diagnostic component for determining whether a fault occurs at the corresponding monitoring node.

[0039] Preferably, the data analysis device comprises:

[0040] A data comparison module is used to calculate the actual measured temperature and temperature difference parameters of the power battery system based on the received temperature data, and compare them with the safety range of the preset temperature value;

[0041] A first judgment module is used to judge whether the power battery system meets the test state under a preset ambient temperature;

[0042] A discharge test module, used to perform a discharge test on the power battery system according to the discharge power of each discharge test item;

[0043] A second judgment module is used to judge whether the difference between the current temperature value of the power battery system and the preset temperature value is within a preset range after the power battery system performs the discharge test and the charging test items;

[0044] A power reduction processing module is used to reduce the discharge power of the current discharge test item according to the actual temperature change of the battery;

[0045] An adjustment module is used to set and adjust a preset temperature value so that the difference between the current temperature value of the power battery system and the preset temperature reference value is within a preset range;

[0046] A charging test module, used to perform a charging test on the power battery system according to the charging parameters of each charging test item;

[0047] The warning module is used to detect potential battery runaway risks and transmit warning signals to relevant personnel based on the above detection characteristics.

[0048] Preferably, the diagnostic component includes an electrically connected fault judgment module and an indicator light, wherein the fault judgment module is used to identify fault conditions of different sensors and circuits, and to indicate whether the sensors and circuits meet the fault conditions through the indicator light.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present invention involves multiple links such as temperature monitoring, discharge test, temperature difference judgment, power adjustment and charging test, which are convenient for comprehensively evaluating the thermal balance performance of a power battery system during the charging and discharging process, timely discovering and solving potential battery out-of-control problems, thereby ensuring the safety and performance of the battery and extending the service life. By reducing power and adjusting preset temperature values, the thermal balance performance of the power battery system is improved, thereby ensuring that the temperature change of the power battery during the charging and discharging process is always within a safe range. A thermal balance rapid test system for the power battery system is provided, and under the mutual cooperation of an indicator light and a fault judgment module, fault judgment can be performed on sensors and circuits in real time, thereby avoiding problems in data output and facilitating relevant personnel to perform timely inspection and maintenance operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a schematic diagram of the steps of the present invention.

[0052] Figure 2 It is a schematic flow chart of step S1 of the present invention.

[0053] Figure 3 It is a schematic diagram of the process of step S2 of the present invention.

[0054] Figure 4 It is a schematic flow chart of step S3 of the present invention.

[0055] Figure 5 It is a schematic diagram of the process of step S4 of the present invention.

[0056] Figure 6 It is a structural schematic diagram of the testing system of the present invention.

[0057] Figure 7 It is a schematic diagram of the structure of the testing device of the present invention.

[0058] Figure 8 It is a structural schematic diagram of the data analysis device of the present invention.

[0059] Notes on the accompanying drawings: network database 100, testing device 200, temperature sensor 210, flow sensor 220, fault judgment module 230, indicator light 240, data analysis device 300, data comparison module 310, first judgment module 320, discharge test module 330, second judgment module 340, power reduction processing module 350, adjustment module 360, charging test module 370, warning module 380, processor 400. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0061] In this embodiment, if Figure 1-Figure 8 As shown, a method for rapid testing the thermal balance of a power battery system is provided. The power battery system is placed in a temperature-controlled environment, such as a temperature-controlled room or a test box, to ensure that the ambient temperature is stable near a preset temperature value. If the initial temperature of the battery pack deviates greatly from the preset temperature value, a cooling fan, a coolant pump, and a coolant are required to cool the battery pack until the overall temperature of the battery pack is close to the preset value and remains stable. The method includes the following steps:

[0062] S1. Conduct a preliminary assessment of the current thermal balance state of the power battery system and set a reasonable preset temperature value based on the design specifications and working environment requirements of the power battery system;

[0063] S2. At the preset temperature value, simulate the load conditions in actual use, perform the discharge test items of the power battery system, and continuously monitor and record the temperature changes of each temperature measuring point during the discharge process;

[0064] S3, calculating the temperature difference between each temperature measurement point, if the temperature difference exceeds the preset range, reducing the discharge power, after the discharge test and the power reduction process, adjusting the preset temperature value according to the actual temperature change of the battery;

[0065] S4. After completing the discharge test and adjustment, simulate the charging conditions in actual use, perform the charging test items of the power battery system, and continuously monitor and record the temperature changes of the battery during the charging process;

[0066] S5. Analyze the current thermal equilibrium state of the power battery system based on the above test data and parameters;

[0067] Thermal balance means that under certain environmental conditions, the temperature difference between each single cell or module in the power battery system is kept within the allowable range, and the overall system temperature tends to be stable and no longer changes significantly. By monitoring the temperature changes of each temperature measuring point in the battery pack over a period of time (such as 1 hour), if the temperature change rate is less than the preset threshold (such as ±0.5℃ / hour), the power battery system is considered to have reached thermal equilibrium.

[0068] Among them Figure 1 and Figure 2 As shown, step S1 includes:

[0069] S11. Measure the temperature of each single battery in the battery pack to observe whether its distribution is uniform, and monitor the temperature changes of each temperature measuring point in the battery pack over a period of time. If the temperature distribution is quite different, it indicates that the parameters inside the power battery system need to be adjusted and optimized to avoid the heat generated by multiple battery packs being different, resulting in higher temperatures at some locations and lower temperatures at other locations, so as to avoid affecting the upper temperature limit of the fixed value;

[0070] S12. According to the optimal operating temperature range of the battery pack, select an intermediate value as the preset temperature value. This temperature value will be used for environmental control and result comparison in subsequent tests. The optimal operating temperature range of the battery pack is usually 20°C to 35°C. You can select an intermediate value as the preset temperature value, such as 25°C. The preset temperature value can be determined based on the battery type and system design requirements to ensure that the battery operates within the normal operating range while avoiding adverse effects on battery performance due to overheating or overcooling.

[0071] Among them Figure 1 and Figure 3 As shown, step S2 includes:

[0072] S21. After confirming that all safety measures are in place, ensure that the voltage and current parameters of the battery pack are within the monitoring range and meet the test standards during the discharge process under the preset temperature value environment, and then discharge the battery pack according to the standard discharge procedure, such as constant current discharge to a specific SOC, such as 80% to 20%. Through the discharge test, the temperature change of the battery during the discharge process can be observed to fully stimulate the thermal effect inside the battery. According to the actual use scenario of the power battery system, the corresponding load equipment such as motor controller, inverter or other simulated load device is configured to simulate the actual power demand of the electric vehicle during driving, and the discharge strategy is formulated, including but not limited to the discharge current, discharge time, discharge depth and other parameters to simulate different working conditions in actual use;

[0073] S22. Use a high-precision testing device 200 and a data analysis device 300 to continuously monitor and record the temperature changes at each temperature measuring point during the discharge process. The temperature measuring points should cover all key areas of the battery pack, including but not limited to battery cells, connections between modules, and heat sinks. Record key indicators such as the highest temperature, lowest temperature, average temperature, and temperature difference at each temperature measuring point during the discharge process. If the temperature difference exceeds a preset range, it indicates that the system thermal balance is not good.

[0074] Among them Figure 1 and Figure 4 As shown, if the temperature difference exceeds the range, the discharge power needs to be reduced according to the specific situation. By reducing the discharge power, the heat generation inside the battery can be reduced, which helps to restore the thermal balance state to ensure that the power battery system can operate within a more suitable temperature range. Step S3 includes:

[0075] S31. After the power battery system executes each discharge test item, determine whether the difference between the current temperature value of the power battery system and the preset temperature value is within a preset range;

[0076] S32, calculating the temperature difference between each temperature measurement point, if the difference between the current temperature value of the power battery system and the preset temperature value is not within the preset range, reducing the discharge power of the current discharge test item;

[0077] S33, if the difference between the current temperature value of the power battery system and the preset temperature value is still not within the preset range after the power reduction process, the discharge power of the current discharge test item is reduced again until the difference between the current temperature value of the power battery system and the preset temperature value is within the preset range;

[0078] S34. If the discharge power of the power battery system still does not meet the preset condition after the power reduction process, adjust the preset temperature value;

[0079] The temperature difference judgment formula is used to determine whether the temperature difference inside the battery system is within the allowable range, and the power adjustment formula is used to adjust the discharge power. During the discharge test, if the temperature difference exceeds the allowable range, it is necessary to restore the thermal equilibrium state by adjusting the discharge power. The size of the power adjustment usually depends on the size of the temperature difference and the thermal response characteristics of the power battery system. The corresponding formula is as follows:

[0080] ΔT=|T measured -T reference |

[0081] P adjusted =P initial ·(1-α·ΔT)

[0082] Where ΔT represents the temperature difference, T measuredIndicates the actual measured temperature, T reference Indicates the preset temperature reference value, P adjusted Represents the adjusted discharge power, P initial It represents the initial discharge power, and α is the adjustment coefficient, which can be determined according to the system characteristics and test requirements.

[0083] Among them Figure 1 and Figure 5 As shown, step S4 includes:

[0084] S41. After the discharge test is completed and the temperature is restored to the preset value, confirm that all safety measures are in place and the charging equipment is correctly connected, and then charge the battery pack according to the standard charging procedures to ensure that the voltage and current parameters of the battery pack are within the monitoring range during the charging process and meet the test standards, such as constant voltage and constant current charging to full power;

[0085] S42. Use a high-precision testing device 200 and a data analysis device 300 to continuously monitor and record the temperature changes at each temperature measuring point during the charging process. The temperature measuring points should cover all key areas of the battery pack. Through the charging test, it can be further verified whether the thermal balance state of the power battery system is restored or improved.

[0086] Among them Figure 1 As shown, the thermal equilibrium state in step S5 is analyzed using the thermal equilibrium equation formula, and the thermal equilibrium equation formula is as follows:

[0087] Q a +Q e =c·m·(T measured -T0)+k·S·(T measured -T env )

[0088] Among them, Q a Indicates the heat generated inside the battery pack, Q e represents the input heat from the outside of the battery pack, c represents the specific heat capacity of the battery, m represents the mass of the battery, the specific heat capacity and mass can be obtained by consulting the network database 100, T0 represents the initial temperature of the battery, k represents the heat dissipation coefficient between the battery and the environment, S represents the heat dissipation area of ​​the battery, that is, the area of ​​the battery surface in contact with the environment, which can be calculated according to the geometric shape and size of the battery, T env Indicates the ambient temperature, which is the temperature of the air or liquid surrounding the battery pack.

[0089] Among them Figure 6-Figure 8 As shown, a thermal balance rapid testing system for a power battery system is also included, and the testing system includes:

[0090] The network database 100 is used to collect, store and provide historical data and big data information of the thermal balance of the power battery system, and divide the data in the corresponding information into several groups according to time, temperature, and charge and discharge state parameters;

[0091] The test device 200 is used to monitor and collect the temperature of each temperature measuring point of the power battery system and the flow parameters of the battery pack coolant in real time;

[0092] The data analysis device 300 is used to collect data from the test device 200 and evaluate the thermal balance state of the battery pack through data processing and data analysis operations;

[0093] The processor 400 is used to receive and output information results from various modules and the network database 100, and to control various information and output coordination instructions.

[0094] Among them Figure 6 and Figure 7 As shown, the test device 200 includes a plurality of temperature sensors 210 and flow sensors 220. The temperature sensor 210 is used to monitor the temperature changes at a plurality of temperature measuring points of the battery, and the temperature sensor 210 can monitor the initial temperature of the battery, the ambient temperature outside the battery pack, and the temperature changes during the battery charging and discharging process. The flow sensor 220 is used to monitor the coolant flow changes at a plurality of key areas of the battery in real time. A diagnostic component is provided on one side of the sensor for determining whether a fault occurs at the corresponding monitoring node. The test device 200 also includes a plurality of heat meters for monitoring the heat generated inside the battery pack and the input heat outside the battery pack, so as to facilitate thermal balance evaluation operations.

[0095] Among them Figure 6 and Figure 8 As shown, the data analysis device 300 includes:

[0096] The data comparison module 310 is used to calculate the actual measured temperature and temperature difference parameters of the power battery system according to the received temperature data, and compare them with the safety range of the preset temperature value;

[0097] The first judgment module 320 is used to judge whether the power battery system meets the test state under the preset ambient temperature, including but not limited to checking whether the ambient temperature is within the allowable range and whether the initial state of the battery system is stable. After the above conditions are met, subsequent discharge test and charge test are performed to improve the accuracy of thermal balance evaluation;

[0098] The discharge test module 330 is used to perform a discharge test on the power battery system according to the discharge power of each discharge test item. During the test, the system monitors the temperature change and discharge current and other parameters of the battery in real time to ensure the safety and accuracy of the test;

[0099] The second judgment module 340 is used to judge whether the difference between the current temperature value of the power battery system and the preset temperature value is within a preset range after the power battery system performs the discharge test and the charge test items;

[0100] The power reduction processing module 350 is used to reduce the discharge power of the current discharge test item according to the actual temperature change of the battery. If it is found that the temperature difference exceeds the range, the discharge test can be re-performed by reducing the discharge power until the temperature difference meets the requirement, which helps to reduce the heat generation of the battery;

[0101] An adjustment module 360 ​​is used to set and adjust a preset temperature value so that the difference between the current temperature value of the power battery system and the preset temperature reference value is within a preset range, so as to improve the thermal balance state of the battery;

[0102] A charging test module 370 is used to perform a charging test on the power battery system according to the charging parameters of each charging test item, and also monitor the temperature change and other parameters of the battery in real time during the test;

[0103] The warning module 380 is used to detect potential battery out-of-control risks and transmit warning signals to relevant personnel based on the above-mentioned detection characteristics. If an abnormal situation is detected, the testing device 200 and the data analysis device 300 will immediately stop the test and trigger an alarm.

[0104] Among them Figure 7 As shown, the diagnostic component includes an electrically connected fault judgment module 230 and an indicator light 240. The fault judgment module 230 is used to identify the fault conditions of different sensors and circuits, and to prompt whether the sensors and circuits meet the fault conditions through the indicator light 240. Through the fault judgment module 230, the circuits of the sensors and circuits can be inspected to avoid circuit short circuits.

[0105] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for rapid testing thermal balance of a power battery system, characterized in that: The following steps are involved: S1. Conduct a preliminary assessment of the current thermal balance state of the power battery system and set a reasonable preset temperature value based on the design specifications and working environment requirements of the power battery system; S2. At the preset temperature value, simulate the load conditions in actual use, perform the discharge test items of the power battery system, and continuously monitor and record the temperature changes of each temperature measuring point during the discharge process; S3, calculating the temperature difference between each temperature measurement point, if the temperature difference exceeds the preset range, reducing the discharge power, after the discharge test and the power reduction process, adjusting the preset temperature value according to the actual temperature change of the battery; S4. After completing the discharge test and adjustment, simulate the charging conditions in actual use, perform the charging test items of the power battery system, and continuously monitor and record the temperature changes of the battery during the charging process; S5. Analyze the current thermal equilibrium state of the power battery system based on the above test data and parameters.

2. A method for rapid thermal balance testing of a power battery system according to claim 1, characterized in that: The step S1 comprises: S11. Measure the temperature of each single cell in the battery pack to see whether its distribution is uniform, and monitor the temperature changes of each temperature measuring point in the battery pack over a period of time. If the temperature distribution is quite different, it indicates that the parameters inside the power battery system need to be adjusted and optimized. S12. According to the optimal operating temperature range of the battery pack, select an intermediate value as the preset temperature value. This temperature value will be used for environmental control and result comparison in subsequent tests.

3. The method for rapid thermal balance testing of a power battery system according to claim 1, characterized in that: The step S2 comprises: S21. After confirming that all safety measures are in place, ensure that the voltage and current parameters of the battery pack are within the monitoring range and meet the test standards during the discharge process under the preset temperature value environment, and then discharge the battery pack according to the standard discharge procedure; S22. Use a high-precision testing device (200) and a data analysis device (300) to continuously monitor and record the temperature changes of each temperature measuring point during the discharge process. The temperature measuring points should cover various key areas of the battery pack, including but not limited to battery cells, connections between modules, and heat sinks.

4. The method for rapid thermal balance testing of a power battery system according to claim 1, characterized in that: The step S3 comprises: S31. After the power battery system executes each discharge test item, determine whether the difference between the current temperature value of the power battery system and the preset temperature value is within a preset range; S32, calculating the temperature difference between each temperature measurement point, if the difference between the current temperature value of the power battery system and the preset temperature value is not within the preset range, reducing the discharge power of the current discharge test item; S33, if the difference between the current temperature value of the power battery system and the preset temperature value is still not within the preset range after the power reduction process, the discharge power of the current discharge test item is reduced again until the difference between the current temperature value of the power battery system and the preset temperature value is within the preset range; S34. If the discharge power of the power battery system still does not meet the preset condition after the power reduction process, adjust the preset temperature value; The temperature difference judgment formula is used to determine whether the temperature difference inside the battery system is within the allowable range, and the power adjustment formula is used to adjust the discharge power. The corresponding formula is as follows: ΔT=|T measured -T reference | P adjusted =P initial ·(1-α·ΔT) Where ΔT represents the temperature difference, T measured Indicates the actual measured temperature, T reference Indicates the preset temperature reference value, P adjusted Represents the adjusted discharge power, P initial represents the initial discharge power, and α is the adjustment coefficient.

5. The method for rapid thermal balance testing of a power battery system according to claim 1, characterized in that: The step S4 comprises: S41. After the discharge test is completed and the temperature is restored to the preset value, confirm that all safety measures are in place and the charging equipment is correctly connected, and then charge the battery pack according to the standard charging procedures to ensure that the voltage and current parameters of the battery pack are within the monitoring range during the charging process and meet the test standards; S42. Use a high-precision testing device (200) and a data analysis device (300) to continuously monitor and record temperature changes at each temperature measuring point during the charging process. The temperature measuring points should cover all key areas of the battery pack.

6. A method for rapid thermal balance testing of a power battery system according to claim 4, characterized in that: The thermal equilibrium state in step S5 is analyzed using a thermal equilibrium equation, which is as follows: Q a +Q e =c·m·(T measured -T0)+k·S·(T measured -T env ) Among them, Q a Indicates the heat generated inside the battery pack, Q e represents the input heat from the outside of the battery pack, c represents the specific heat capacity of the battery, m represents the mass of the battery, T0 represents the initial temperature of the battery, k represents the heat dissipation coefficient between the battery and the environment, S represents the heat dissipation area of ​​the battery, and T env Indicates the ambient temperature.

7. A method for rapid testing thermal balance of a power battery system according to claims 1-6, characterized in that: Also included is a thermal balance rapid testing system for a power battery system, the testing system comprising: A network database (100) is used to collect, store and provide historical data and big data information of thermal balance of a power battery system, and divide a plurality of data in the corresponding information into a plurality of groups according to time, temperature and charge and discharge state parameters; A testing device (200) for real-time monitoring and collecting the temperature of each temperature measuring point of the power battery system and the flow parameters of the battery pack coolant; A data analysis device (300) for collecting data from the test device (200) and evaluating the thermal balance state of the battery pack through data processing and data analysis operations; The processor (400) is used to receive and output information results of various modules and the network database (100), and to control various information and output coordination instructions.

8. A method for rapid testing thermal balance of a power battery system according to claim 7, characterized in that: The test device (200) comprises a plurality of temperature sensors (210) and a flow sensor (220), wherein the temperature sensor (210) is used to monitor temperature changes at a plurality of temperature measurement points of a battery, and the flow sensor (220) is used to monitor in real time the flow changes of coolant at a plurality of key areas of the battery, and a diagnostic component is provided on one side of each of the sensors for determining whether a fault occurs at a corresponding monitoring node.

9. A method for rapid thermal balance testing of a power battery system according to claim 7, characterized in that: The data analysis device (300) comprises: A data comparison module (310) is used to calculate the actual measured temperature and temperature difference parameters of the power battery system according to the received temperature data, and compare them with the safety range of the preset temperature value; A first judgment module (320) is used to judge whether the power battery system meets the test state at a preset ambient temperature; A discharge test module (330), used for performing a discharge test on the power battery system according to the discharge power of each discharge test item; A second judgment module (340) is used to judge whether the difference between the current temperature value of the power battery system and the preset temperature value is within a preset range after the power battery system performs the discharge test and the charge test items; A power reduction processing module (350) is used to reduce the discharge power of the current discharge test item according to the actual temperature change of the battery; An adjustment module (360) is used to set and adjust a preset temperature value so that the difference between the current temperature value of the power battery system and the preset temperature reference value is within a preset range; A charging test module (370), used to perform a charging test on the power battery system according to the charging parameters of each charging test item; The warning module (380) is used to detect potential battery runaway risks and transmit a warning signal to relevant personnel based on the above detection characteristics.

10. A method for rapid thermal balance testing of a power battery system according to claim 8, characterized in that: The diagnostic component comprises an electrically connected fault judgment module (230) and an indicator light (240), wherein the fault judgment module (230) is used to identify fault conditions of different sensors and circuits, and to indicate whether the sensors and circuits meet the fault conditions through the indicator light (240).

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