Power battery safety boundary test method, device, medium and equipment

Abstract

The invention provides a power battery safety boundary test method and device, a medium and equipment, and the method comprises the steps: carrying out the static extrusion test of a to-be-tested power battery, recording a pressure value, a temperature value, a voltage value and deformation in the test process, and carrying out the fitting to obtain a pressure curve, a temperature curve, a voltage curve and a deformation curve; determining a pressure boundary point by combining the pressure curve and the temperature curve, determining a deformation quantity boundary point by combining the deformation quantity curve and the pressure boundary point, and determining a voltage boundary point according to the voltage curve, so as to test and determine the safety boundary of the power battery from multiple dimensions of pressure, deformation quantity and voltage. The thermal runaway, the pressure, the deformation quantity and the voltage of the power battery are quantified, so that the safety of the power battery is improved, and meanwhile, the performance of the power battery is favorably improved.

Description

Technical Field

[0001] This application relates to the field of battery testing technology, specifically to a method, apparatus, medium, and equipment for testing the safety boundaries of a power battery. Background Technology

[0002] With the rapid development of new energy vehicles, the power battery, as a core component, has become a key technological challenge, particularly regarding battery safety. The accuracy and timeliness of the power battery's safety boundaries are crucial for early warning systems. Common causes of thermal runaway include thermal abuse, electrical abuse, and mechanical abuse. Mechanical abuse is very common and difficult to avoid during driving. For example, in a vehicle collision, the massive impact can cause deformation or even puncture of the battery pack. Many other forms of mechanical abuse are insidious, such as when a car travels over potholes, protrusions, or rocky surfaces, causing impacts and scrapes to the chassis, leading to battery pack deformation and potentially triggering thermal runaway in the cells. While thermal diffusion occurs in the battery pack under mechanical abuse conditions, the relationship between mechanical abuse and electrical / thermal factors is difficult to quantify, and there is a lack of battery safety boundaries specifically for mechanical abuse. Therefore, a method for accurately testing and determining the safety boundaries of power batteries is urgently needed. Summary of the Invention

[0003] To address the aforementioned technical problems, this application is proposed. Embodiments of this application provide a method, apparatus, medium, and device for testing the safety boundaries of a power battery.

[0004] According to one aspect of this application, a method for testing the safety boundary of a power battery is provided, comprising: performing a static compression test on the power battery under test, and recording the pressure value, temperature value, voltage value, and deformation of the power battery under test during the static compression test; fitting a pressure curve, a temperature curve, a voltage curve, and a deformation curve of the power battery under test based on the pressure value, the temperature value, the voltage value, and the deformation curve, respectively; determining the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve; determining the deformation boundary point of the power battery under test based on the deformation curve and the pressure boundary point; and determining the voltage boundary point of the power battery under test based on the voltage curve.

[0005] In one embodiment, before determining the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve, the power battery safety boundary test method further includes: determining the thermal runaway time of the power battery under test based on the temperature curve.

[0006] In one embodiment, determining the thermal runaway time of the power battery under test based on the temperature curve includes: selecting the point corresponding to the maximum slope of the tangent line of the temperature curve as the thermal runaway point; and taking the time corresponding to the thermal runaway point as the thermal runaway time.

[0007] In one embodiment, determining the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve includes: using the pressure value corresponding to the thermal runaway time as the pressure boundary point.

[0008] In one embodiment, determining the deformation boundary point of the power battery under test based on the deformation curve and the pressure boundary point includes: taking the deformation at the time corresponding to the pressure boundary point as the deformation boundary point.

[0009] In one embodiment, determining the voltage boundary point of the power battery under test based on the voltage curve includes: calculating the voltage boundary point based on the maximum value of the voltage curve and a preset ratio.

[0010] In one embodiment, recording the pressure, temperature, voltage, and deformation values ​​of the power battery under test in the static extrusion test includes: acquiring the pressure, temperature, and voltage values ​​of the power battery under test in the static extrusion test using a pressure sensor, a temperature sensor, and a voltage sensor, respectively; acquiring a deformation image of the power battery under test in the static extrusion test; and calculating the deformation value based on the deformation image.

[0011] According to another aspect of this application, a power battery safety boundary testing device is provided, comprising: a test parameter acquisition module, used to perform a static extrusion test on the power battery under test and record the pressure value, temperature value, voltage value, and deformation of the power battery under test in the static extrusion test; a parameter curve fitting module, used to fit the pressure curve, temperature curve, voltage curve, and deformation curve of the power battery under test based on the pressure value, temperature value, voltage value, and deformation, respectively; a pressure boundary determination module, used to determine the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve; a deformation boundary determination module, used to determine the deformation boundary point of the power battery under test based on the deformation curve and the pressure boundary point; and a voltage boundary determination module, used to determine the voltage boundary point of the power battery under test based on the voltage curve.

[0012] According to another aspect of this application, a computer-readable storage medium is provided, the storage medium storing a computer program for performing any of the methods described above.

[0013] According to another aspect of this application, an electronic device is provided, comprising: a processor; a memory for storing processor-executable instructions; the processor being configured to perform any of the methods described above.

[0014] This application provides a method, apparatus, medium, and equipment for testing the safety boundaries of a power battery. The method involves conducting a static extrusion test on the power battery under test and recording the pressure, temperature, voltage, and deformation values ​​during the test. Based on these values, pressure, temperature, voltage, and deformation curves are fitted to obtain the power battery's pressure, temperature, voltage, and deformation curves, respectively. The pressure and temperature curves are used to determine the pressure boundary points of the power battery. The deformation boundary points are also determined based on the deformation curves and pressure boundary points. Finally, the voltage boundary points are determined based on the voltage curves. Boundary points; this involves using a static compression test to test the power battery under test and recording the pressure, temperature, voltage, and deformation values ​​during the test. Pressure curves, temperature curves, voltage curves, and deformation curves are then fitted. Pressure boundary points are determined by combining the pressure and temperature curves, deformation boundary points by combining the deformation curve and pressure boundary points, and voltage boundary points by determining the voltage curve. This allows for the determination of the power battery's safety boundaries from multiple dimensions, including pressure, deformation, and voltage. This quantifies the thermal runaway of the power battery in relation to pressure, deformation, and voltage, thereby improving the safety of the power battery and contributing to its performance enhancement. Attached Figure Description

[0015] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0016] Figure 1 This is a flowchart illustrating a power battery safety boundary testing method provided in an exemplary embodiment of this application.

[0017] Figure 2 This is a schematic diagram of the structure of a static extrusion test provided in an exemplary embodiment of this application.

[0018] Figure 3 This is a schematic diagram of the relationship between temperature and pressure during a static extrusion test provided in an exemplary embodiment of this application.

[0019] Figure 4 This is a schematic diagram of the relationship between pressure and voltage during a static extrusion test provided in an exemplary embodiment of this application.

[0020] Figure 5 This is a schematic diagram of the structure of a power battery safety boundary testing device provided in an exemplary embodiment of this application.

[0021] Figure 6 This is a structural diagram of an electronic device provided in an exemplary embodiment of this application.

[0022] Explanation of reference numerals in the attached drawings: 1. Extrusion equipment; 2. Power battery under test; 10. Electronic equipment; 11. Processor; 12. Memory; 13. Input device; 14. Output device. Detailed Implementation

[0023] Hereinafter, exemplary embodiments according to this application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein.

[0024] Figure 1 This is a flowchart illustrating an exemplary embodiment of the power battery safety boundary testing method provided in this application. Figure 1 As shown, the power battery safety boundary test method includes the following steps: Step 110: Perform a static extrusion test on the power battery to be tested, and record the pressure, temperature, voltage and deformation values ​​of the power battery to be tested during the static extrusion test.

[0025] This application involves a static compression test on the power battery under test, specifically as follows: Figure 2 As shown, the extrusion device 1 is used to extrude the power battery 2 under test, and the pressure value, temperature value, voltage value and deformation of the power battery 2 under test are recorded during the static extrusion test. That is, the performance of the power battery 2 under test in terms of force, temperature, voltage and deformation during the static extrusion test is recorded.

[0026] Step 120: Based on the pressure value, temperature value, voltage value, and deformation, the pressure curve, temperature curve, voltage curve, and deformation curve of the power battery under test are obtained respectively.

[0027] After the static extrusion test is completed, all recorded pressure, temperature, voltage and deformation values ​​are summarized and outliers are removed to obtain pressure, temperature, voltage and deformation values ​​at different times. Based on the pressure, temperature, voltage and deformation values ​​at different times, the pressure curve, temperature curve, voltage curve and deformation curve of the power battery under test in the static extrusion test are respectively fitted.

[0028] Step 130: Based on the pressure curve and temperature curve, determine the pressure boundary point of the power battery to be tested.

[0029] After fitting the pressure curve, temperature curve, voltage curve and deformation curve, this application combines the pressure curve and temperature curve to comprehensively determine the pressure boundary point of the power battery under test, thereby obtaining the critical pressure value of the power battery under test before thermal runaway, that is, when the pressure on the power battery under test exceeds the pressure boundary point, there will be a risk of thermal runaway.

[0030] Step 140: Determine the deformation boundary points of the power battery to be tested based on the deformation curve and pressure boundary points.

[0031] This application combines deformation curves and pressure boundary points to comprehensively determine the deformation boundary points of the power battery under test, thereby obtaining the deformation boundary points of the power battery under test before thermal runaway. That is, when the deformation of the power battery under test exceeds the deformation boundary points, there is a risk of thermal runaway.

[0032] Step 150: Based on the voltage curve, determine the voltage boundary point of the power battery to be tested.

[0033] This application determines the voltage boundary point of the power battery under test based on the voltage curve, thereby obtaining the voltage boundary point of the power battery under test before thermal runaway. That is, when the voltage of the power battery under test exceeds the voltage boundary point, there is a risk of thermal runaway.

[0034] This application provides a method for testing the safety boundaries of a power battery. The method involves conducting a static extrusion test on the power battery under test and recording the pressure, temperature, voltage, and deformation values ​​during the test. Based on these values, pressure, temperature, voltage, and deformation curves are fitted to obtain the power battery's pressure, temperature, voltage, and deformation curves, respectively. The pressure and temperature curves are used to determine the pressure boundary points of the power battery. The deformation boundary points are also determined based on the deformation curves and pressure boundary points. Finally, the voltage boundary points are determined based on the voltage curves. A static extrusion test is used to test the power battery under test and record the pressure, temperature, voltage and deformation values ​​during the test. Pressure curve, temperature curve, voltage curve and deformation curve are obtained by fitting. The pressure boundary point is determined by combining the pressure curve and temperature curve, the deformation boundary point is determined by combining the deformation curve and pressure boundary point, and the voltage boundary point is determined by the voltage curve. In this way, the safety boundary of the power battery is determined by testing from multiple dimensions of pressure, deformation and voltage. This allows for the quantification of thermal runaway of the power battery and the relationship between pressure, deformation and voltage, thereby improving the safety of the power battery and contributing to the improvement of its performance.

[0035] In one embodiment, prior to step 130, the above-mentioned power battery safety boundary test method may further include: determining the thermal runaway time of the power battery under test based on the temperature curve.

[0036] Excessive mechanical compression leads to side reactions within the tested power battery. These side reactions generate heat, and the resulting temperature rise eventually triggers a chain reaction within the battery. At this stage, the battery temperature becomes irreversible, i.e., thermal runaway. This application, after fitting the temperature curve, determines the thermal runaway time of the tested power battery based on the temperature curve, i.e., it obtains the time point corresponding to thermal runaway (temperature runaway) based on the temperature curve.

[0037] In one embodiment, the thermal runaway time of the power battery under test can be specifically determined by: selecting the point corresponding to the maximum slope of the tangent of the temperature curve as the thermal runaway point; and taking the time corresponding to the thermal runaway point as the thermal runaway time.

[0038] Specifically, this application can calculate the slope of the tangent line at each data point on the temperature curve and select the point with the maximum slope (i.e. the point with the fastest temperature rise) as the thermal runaway point. That is, this point is the point where the temperature of the power battery under test rises rapidly (i.e., the heat is about to run away or has already entered a runaway state), and the time corresponding to this thermal runaway point is taken as the thermal runaway time.

[0039] In one embodiment, step 130 can be implemented by using the pressure value corresponding to the thermal runaway time as the pressure boundary point.

[0040] like Figure 3 As shown, during the initial stage of static extrusion, the multi-layered structure of the tested power battery is continuously compacted, and the force fed back to the sensor continuously increases. During the later stage of static extrusion, as gas accumulates inside the battery, the internal pressure gradually increases until the pressure relief valve opens, releasing the gas. At this stage, the battery pressure (load) rises to a maximum value and then rapidly decreases. This application, after determining the thermal runaway time, uses the pressure value corresponding to the thermal runaway time as the pressure boundary point. That is, when the extrusion force applied to the tested power battery reaches this pressure boundary point, there is a risk of thermal runaway. It should be understood that this application can also select other pressure values ​​as the pressure boundary point according to the needs of the actual application scenario. For example, a fixed value (e.g., 130kN) can be set based on the extrusion force limit value in the standard or actual scenario, and this fixed value can be used as the pressure boundary value. This application does not limit the method for determining the pressure boundary point.

[0041] In one embodiment, step 140 can be implemented by taking the deformation at the time corresponding to the pressure boundary point as the deformation boundary point.

[0042] After determining the pressure boundary point, this application determines the corresponding time in the pressure curve based on the pressure boundary point, and uses the deformation in the deformation curve corresponding to that time as the deformation boundary point. This means that when the deformation of the power battery under test reaches this deformation boundary point, there is a risk of thermal runaway. It should be understood that this application can also select other deformations as deformation boundary points according to the needs of actual application scenarios. For example, a fixed value (e.g., 37.5% of the size) can be set based on the deformation limit value in standards or actual scenarios, and this fixed value can be used as the deformation boundary value. This application does not limit the method for determining the deformation boundary point.

[0043] In one embodiment, step 150 can be implemented by calculating the voltage boundary point based on the maximum value of the voltage curve and a preset ratio.

[0044] like Figure 4 As shown, mechanical abuse can lead to diaphragm collapse, causing a localized internal short circuit in the tested power battery, resulting in voltage drop, heat generation from side reactions, and as mechanical abuse continues, the number of ruptured areas in the diaphragm increases, the voltage drop rate accelerates, and heat begins to accumulate. When the temperature reaches a certain level, the diaphragm melts, causing a large-scale internal short circuit in the tested power battery, and the voltage rapidly drops to 0V. This application sets a voltage boundary point based on the maximum voltage of the tested power battery (open circuit voltage under 100% SOC conditions) and a pre-set percentage (e.g., 7%). If the voltage of the tested power battery rapidly drops to the voltage boundary point within a short period of time (e.g., 0.5 seconds to 1 second) (e.g., the rate of drop is greater than the preset value), it is determined that the tested power battery will immediately experience thermal runaway.

[0045] In one embodiment, step 110 can be implemented as follows: a pressure sensor, a temperature sensor, and a voltage sensor are used to collect the pressure, temperature, and voltage values ​​of the power battery under test in a static extrusion test; deformation images of the power battery under test in a static extrusion test are collected; and the deformation is calculated based on the deformation images.

[0046] This application can collect the pressure, temperature and voltage values ​​of the power battery under test during a static extrusion test by setting pressure sensors, temperature sensors and voltage sensors on the power battery under test, and record the deformation image of the power battery under test in real time during the static extrusion test by using high-speed cameras and other devices. By calculating the image area of ​​the power battery under test during the static extrusion test, the deformation of the power battery under test can be determined.

[0047] Optionally, this application can charge the power battery to be tested before the static extrusion test, wherein the charging rate range is 0.05~0.5C, and the battery is left to stand for 6~24 hours before the static extrusion test, and the ambient temperature during the standing period should be the same as the ambient temperature during the static extrusion test (e.g., 20℃~40℃). Preferably, this application can also perform a voltage verification of the power battery to be tested before the static extrusion test to ensure the accuracy of the voltage before the static extrusion test and reduce the relative error of the test.

[0048] Figure 5 This is a schematic diagram of the structure of a power battery safety boundary testing device provided in an exemplary embodiment of this application. Figure 5 As shown, the power battery safety boundary testing device 20 includes: a test parameter acquisition module 21, used to perform a static extrusion test on the power battery under test and record the pressure, temperature, voltage, and deformation values ​​of the power battery under test during the static extrusion test; a parameter curve fitting module 22, used to fit the pressure curve, temperature curve, voltage curve, and deformation curve of the power battery under test based on the pressure, temperature, voltage, and deformation values, respectively; a pressure boundary determination module 23, used to determine the pressure boundary point of the power battery under test based on the pressure curve and temperature curve; a deformation boundary determination module 24, used to determine the deformation boundary point of the power battery under test based on the deformation curve and pressure boundary point; and a voltage boundary determination module 25, used to determine the voltage boundary point of the power battery under test based on the voltage curve.

[0049] This application provides a power battery safety boundary testing device. The device uses a test parameter acquisition module 21 to perform a static extrusion test on the power battery under test and records the pressure, temperature, voltage, and deformation values ​​during the static extrusion test. A parameter curve fitting module 22 fits the pressure, temperature, voltage, and deformation curves of the power battery under test based on the pressure, temperature, voltage, and deformation values. A pressure boundary determination module 23 determines the pressure boundary points of the power battery under test based on the pressure and temperature curves. A deformation boundary determination module 24 determines the deformation boundary points of the power battery under test based on the deformation curve and the pressure boundary points. A voltage boundary determination module 25... 5. Based on the voltage curve, determine the voltage boundary point of the power battery under test; that is, use a static extrusion test to test the power battery under test and record the pressure, temperature, voltage and deformation values ​​during the test, and fit the pressure curve, temperature curve, voltage curve and deformation curve. Combine the pressure curve and temperature curve to determine the pressure boundary point, combine the deformation curve and pressure boundary point to determine the deformation boundary point, and determine the voltage boundary point according to the voltage curve. In this way, the safety boundary of the power battery is determined from multiple dimensions of pressure, deformation and voltage, so as to quantify the thermal runaway of the power battery with pressure, deformation and voltage, thereby improving the safety of the power battery and helping to improve the performance of the power battery.

[0050] In one embodiment, the above-mentioned power battery safety boundary test device 20 can be further configured to: determine the thermal runaway time of the power battery under test based on the temperature curve.

[0051] In one embodiment, the above-mentioned power battery safety boundary test device 20 can be further configured to: select the point corresponding to the maximum value of the tangent slope of the temperature curve as the thermal runaway point; and take the time corresponding to the thermal runaway point as the thermal runaway time.

[0052] In one embodiment, the pressure boundary determination module 23 can be further configured to: use the pressure value corresponding to the thermal runaway time as the pressure boundary point.

[0053] In one embodiment, the deformation boundary determination module 24 can be further configured to: use the deformation at the time corresponding to the pressure boundary point as the deformation boundary point.

[0054] In one embodiment, the voltage boundary determination module 25 can be further configured to calculate the voltage boundary point based on the maximum value of the voltage curve and a preset ratio.

[0055] In one embodiment, the above-mentioned test parameter acquisition module 21 can be further configured to: acquire the pressure value, temperature value and voltage value of the power battery under test in the static extrusion test using a pressure sensor, a temperature sensor and a voltage sensor respectively; acquire the deformation image of the power battery under test in the static extrusion test; and calculate the deformation based on the deformation image.

[0056] Below, for reference Figure 6 This application describes an electronic device according to embodiments thereof. The electronic device may be either or both of a first device and a second device, or a standalone device independent of them, which may communicate with the first device and the second device to receive acquired input signals from them.

[0057] Figure 6 A block diagram of an electronic device according to an embodiment of this application is illustrated.

[0058] like Figure 6 As shown, the electronic device 10 includes one or more processors 11 and memory 12.

[0059] The processor 11 may be a central processing unit (CPU) or other form of processing unit with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 10 to perform desired functions.

[0060] The memory 12 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 11 may execute the program instructions to implement the methods of the various embodiments of this application described above and / or other desired functions. Various contents such as input signals, signal components, and noise components may also be stored in the computer-readable storage medium.

[0061] In one example, the electronic device 10 may also include an input device 13 and an output device 14, which are interconnected via a bus system and / or other forms of connection mechanism (not shown).

[0062] When the electronic device is a standalone device, the input device 13 can be a communication network connector for receiving the collected input signals from the first device and the second device.

[0063] In addition, the input device 13 may also include, for example, a keyboard, a mouse, etc.

[0064] The output device 14 can output various information to the outside, including determined distance information, direction information, etc. The output device 14 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0065] Of course, for the sake of simplicity, Figure 6 Only some of the components of the electronic device 10 relevant to this application are shown in this illustration; components such as buses, input / output interfaces, etc., are omitted. In addition, the electronic device 10 may include any other suitable components depending on the specific application.

[0066] In addition to the methods and apparatus described above, embodiments of this application may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps in the methods according to various embodiments of this application described in the "Exemplary Methods" section above.

[0067] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0068] Furthermore, embodiments of this application may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps in the methods according to various embodiments of this application described in the "Exemplary Methods" section above.

[0069] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0070] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0071] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0072] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0073] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0074] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method for testing the safety boundary of a power battery, characterized in that, include: A static extrusion test was conducted on the power battery under test, and the pressure, temperature, voltage and deformation values ​​of the power battery under test during the static extrusion test were recorded. Based on the pressure value, temperature value, voltage value, and deformation, the pressure curve, temperature curve, voltage curve, and deformation curve of the power battery under test are respectively fitted. Based on the pressure curve and the temperature curve, the pressure boundary point of the power battery under test is determined. Based on the deformation curve and the pressure boundary point, the deformation boundary point of the power battery under test is determined. Based on the voltage curve, the voltage boundary point of the power battery under test is determined.

2. The power battery safety boundary test method according to claim 1, characterized in that, Before determining the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve, the power battery safety boundary test method further includes: Based on the temperature curve, the thermal runaway time of the power battery under test is determined.

3. The power battery safety boundary test method according to claim 2, characterized in that, Determining the thermal runaway time of the power battery under test based on the temperature curve includes: The point corresponding to the maximum slope of the tangent line of the temperature curve is selected as the thermal runaway point; The time corresponding to the thermal runaway point is taken as the thermal runaway time.

4. The power battery safety boundary test method according to claim 2, characterized in that, The process of determining the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve includes: The pressure value corresponding to the thermal runaway time is taken as the pressure boundary point.

5. The power battery safety boundary test method according to claim 1, characterized in that, The step of determining the deformation boundary points of the power battery under test based on the deformation curve and the pressure boundary points includes: The deformation at the time corresponding to the pressure boundary point is taken as the deformation boundary point.

6. The power battery safety boundary test method according to claim 1, characterized in that, The step of determining the voltage boundary point of the power battery under test based on the voltage curve includes: The voltage boundary point is calculated based on the maximum value of the voltage curve and a preset ratio.

7. The power battery safety boundary test method according to claim 1, characterized in that, The recording of the pressure, temperature, voltage, and deformation values ​​of the power battery under test during the static extrusion test includes: Pressure sensors, temperature sensors, and voltage sensors were used to collect the pressure, temperature, and voltage values ​​of the power battery under test during the static compression test, respectively. The deformation images of the power battery under test were acquired during the static extrusion test. The deformation amount is calculated based on the deformation image.

8. A power battery safety boundary testing device, characterized in that, include: The test parameter acquisition module is used to perform a static extrusion test on the power battery under test and record the pressure, temperature, voltage and deformation values ​​of the power battery under test during the static extrusion test. The parameter curve fitting module is used to fit the pressure curve, temperature curve, voltage curve and deformation curve of the power battery under test based on the pressure value, temperature value, voltage value and deformation, respectively. The pressure boundary determination module is used to determine the pressure boundary point of the power battery under test based on the pressure curve and the temperature curve. The deformation boundary determination module is used to determine the deformation boundary points of the power battery under test based on the deformation curve and the pressure boundary points. The voltage boundary determination module is used to determine the voltage boundary point of the power battery under test based on the voltage curve.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program for performing the method described in any one of claims 1-7.

10. An electronic device, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is used to execute the method described in any one of claims 1-7.

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