A battery swelling force detection method, a battery safety detection device and system

Abstract

The application belongs to the technical field of battery safety detection, and proposes a battery expansion force detection method, a battery safety detection device and a system, which are used to solve the problem of inaccurate battery expansion force detection in the prior art. The method is suitable for the process of detecting the expansion force of the battery by using a thin film pressure sensor. The method comprises the following steps: determining correction information corresponding to the battery to be detected; obtaining detection data of the battery to be detected, the detection data comprising temperature information and an original signal amount output by the thin film pressure sensor; obtaining a response duration of the thin film pressure sensor; correcting the original signal amount according to the temperature information, the response duration and the correction information to obtain a corrected signal amount; and determining expansion force information of the battery to be detected according to the corrected signal amount and calibration information, wherein the calibration information has a preset corresponding relationship between the signal amount and the expansion force.

Description

Technical Field

[0001] This application belongs to the field of battery safety testing technology, and in particular relates to a battery expansion force testing method, battery safety testing device and system. Background Technology

[0002] As a common power source for new energy vehicles, the safety of rechargeable batteries is an important standard for measuring the performance of new energy vehicles. Therefore, it is necessary to conduct regular safety tests on them.

[0003] Currently, various sensors are commonly used to detect multi-dimensional data such as battery temperature, expansion force, and current, and the battery's safety is determined based on this comprehensive data. However, the sensing capability of sensors that detect battery expansion force fluctuates over long-term use, meaning the detected expansion force data deviates from the actual expansion force data. This leads to inaccurate detection of battery expansion force and consequently, inaccurate assessments of battery safety. Summary of the Invention

[0004] In view of this, embodiments of this application provide a battery expansion force detection method, a battery safety detection device and system to solve the problem of inaccurate battery expansion force detection in the prior art.

[0005] The first aspect of this application provides a method for detecting battery expansion force. This method is applicable to the process of detecting battery expansion force using a thin-film pressure sensor. The method includes: acquiring calibration information corresponding to the battery under test; acquiring detection data of the battery under test, including temperature information and the original signal output by the thin-film pressure sensor; acquiring the response time of the thin-film pressure sensor; correcting the original signal based on the temperature information, response time, and calibration information to obtain a corrected signal; and determining the expansion force information of the battery under test based on the corrected signal and calibration information, wherein the calibration information presets a correspondence between the signal and the expansion force.

[0006] In conjunction with the first aspect, in the first possible implementation of the first aspect, the battery under test and the calibration information have a corresponding relationship. The specific steps for obtaining the calibration information are: to obtain the calibration information corresponding to the battery under test according to the model of the battery under test.

[0007] In conjunction with the first aspect, in the second possible implementation of the first aspect, the temperature information is the temperature of the battery under test; or, the temperature information is the temperature of the thin-film pressure sensor; or, the temperature information is the ambient temperature of the thin-film pressure sensor.

[0008] In conjunction with the first aspect, in the third possible implementation of the first aspect, the correction information includes temperature drift correction information and time drift correction information; the specific steps for correcting the original signal quantity based on the temperature information, response duration, and correction information to obtain the corrected signal quantity are as follows: the original signal quantity is corrected based on the temperature information and temperature drift correction information to obtain the first corrected signal quantity; the first corrected signal quantity is corrected based on the response duration and time drift correction information to obtain the corrected signal quantity.

[0009] In conjunction with the first aspect, in the fourth possible implementation of the first aspect, the temperature drift correction information stores a correction model Q and a calibration temperature. The correction model Q is determined based on the relationship between the signal output of the thin-film pressure sensor and the temperature, and the calibration temperature is a preset temperature value. The specific steps for correcting the original signal based on the temperature information and the temperature drift correction information are as follows: the original signal is corrected based on the temperature information and the correction model Q to obtain the first corrected signal corresponding to the calibration temperature.

[0010] In conjunction with the first aspect, in the fifth possible implementation of the first aspect, the calibration information is obtained by calibrating the thin-film pressure sensor within a set temperature range, and the calibration temperature is the temperature value within the set temperature range.

[0011] In conjunction with the first aspect, in the sixth possible implementation of the first aspect, the calibration temperature is the temperature value at which the thin-film pressure sensor is calibrated and the calibration information is obtained.

[0012] In conjunction with the first aspect, in the seventh possible implementation of the first aspect, the time drift correction information includes the correspondence between the correction model K and the response time of the thin-film pressure sensor, wherein the correction model K is determined based on the change relationship between the signal quantity output by the thin-film pressure sensor and time; the specific steps for correcting the first correction signal quantity according to the response time and the time drift correction information to obtain the corrected signal quantity are as follows: the first correction signal quantity is corrected according to the correction model K and the response time to obtain the corrected signal quantity.

[0013] In conjunction with the first aspect, in the eighth possible implementation of the first aspect, the response time is the total duration for which the signal quantity output by the thin-film pressure sensor exceeds a set signal quantity threshold.

[0014] A second aspect of this application provides a battery safety testing device, which includes a data acquisition unit, an expansion force detection unit, and a safety testing unit. The data acquisition unit includes a temperature sensor and a thin-film pressure sensor. The temperature sensor is used to acquire temperature information, and the thin-film pressure sensor outputs a raw signal when squeezed by the battery under test. The expansion force detection unit is used to correct the raw signal based on the usage time, temperature information, and calibration information of the thin-film pressure sensor to obtain a corrected signal, and to determine the expansion force information of the battery under test based on the corrected signal and calibration information. The safety testing unit is used to determine the safety of the battery under test based on the expansion force information.

[0015] In conjunction with the second aspect, in the first possible implementation of the second aspect, the correction information is preset in the expansion force detection unit; or, the correction information is stored in the cloud, and the expansion force detection unit communicates with the cloud to obtain the correction information.

[0016] A third aspect of this application provides a battery safety testing system. The system includes a terminal device and a cloud device. The terminal device is equipped with a battery under test, a temperature sensor, and a thin-film pressure sensor. The cloud device has pre-set calibration and adjustment information corresponding to the thin-film pressure sensor. The terminal device is configured to acquire and send test data of the battery under test to the cloud device. The test data includes temperature information and the raw signal output by the thin-film pressure sensor. The cloud device is configured to receive the test data, determine the expansion force information of the battery under test based on the test data, calibration and adjustment information, and determine the safety of the battery under test based on the expansion force information.

[0017] The beneficial effects of this application embodiment compared with the prior art are as follows: This application embodiment provides a battery expansion force detection method, a battery safety detection device, and a system. When detecting battery expansion force, a thin-film pressure sensor is used. The original signal output by the thin-film pressure sensor is corrected by combining calibration information with temperature information and response time to obtain a corrected signal. This corrected signal avoids the influence of temperature and response time. Therefore, by using the corrected signal and calibration information to determine the expansion force information of the battery under test, more accurate expansion force information can be obtained. Furthermore, by using calibration information and temperature information to correct the original signal to mitigate the influence of temperature on the electrical signal, this method can be used to correct the original signal at different ambient temperatures. In other words, the battery expansion force information obtained by this method is not affected by the ambient temperature of the battery, and has high practicality and versatility. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall process of a battery expansion force detection method provided in an embodiment of this application;

[0020] Figure 2 This is a schematic diagram of the installation of a battery under test and a thin-film pressure sensor provided in an embodiment of this application;

[0021] Figure 3 This is a detailed flowchart illustrating a battery expansion force detection method provided in an embodiment of this application;

[0022] Figure 4 This is a schematic diagram showing the relationship between the signal quantity and temperature of the thin-film pressure sensor provided in this application embodiment;

[0023] Figure 5 This is a schematic diagram showing the relationship between the signal quantity and response time of the thin-film pressure sensor provided in this application embodiment;

[0024] Figure 6 This is a schematic diagram of the battery safety detection device provided in the embodiments of this application;

[0025] Figure 7 This is a schematic diagram of the battery safety detection system provided in the embodiments of this application.

[0026] Explanation of reference numerals in the attached diagram:

[0027] 1-Battery under test; 2-Thin-film pressure sensor. Detailed Implementation

[0028] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0029] The technical solutions provided in this application will be explained in detail below with reference to specific embodiments.

[0030] As a common power source for new energy vehicles, the safety of rechargeable batteries is a crucial standard for evaluating the performance of these vehicles. Therefore, regular safety testing is necessary. Currently, various sensors are typically used to detect multi-dimensional data such as battery temperature, expansion force, and current, and the battery's safety is determined based on this comprehensive data analysis.

[0031] Please see Figure 1 Based on this, the first embodiment of this application provides a battery expansion force detection method. This method is applicable to the process of detecting battery expansion force using a thin-film pressure sensor. The method provided in this embodiment can obtain relatively accurate battery expansion force information. The method includes:

[0032] Determine the calibration information corresponding to the battery under test;

[0033] Acquire the test data of the battery under test, including temperature information and the raw signal output by the thin-film pressure sensor;

[0034] Obtain the response time of the thin-film pressure sensor;

[0035] The original signal is corrected based on temperature information, response time, and correction information to obtain the corrected signal.

[0036] The expansion force information of the battery under test is determined based on the corrected signal quantity and calibration information.

[0037] The calibration information includes a pre-defined correspondence between signal quantities and expansion forces.

[0038] like Figure 2 As shown, in this embodiment, a thin-film pressure sensor 2 is used to detect the battery expansion force. The thin-film pressure sensor 2 is correspondingly set with the battery under test 1. When the battery under test 1 squeezes the thin-film pressure sensor 2, the thin-film pressure sensor 2 will generate a change in signal due to the squeezing force and output a changing signal. The magnitude of this signal changes with the magnitude of the squeezing force. By comparing the calibration information with the signal output by the thin-film pressure sensor 2, the expansion force corresponding to the signal can be obtained.

[0039] The thin-film pressure sensor is a flexible, bendable sensor made of a flexible thin film. Because the properties of flexible thin-film materials change under different environmental temperatures or long-term pressure, these conditions often affect the signal output of the thin-film pressure sensor. Therefore, directly comparing the output signal with calibration information to obtain expansion force information often yields inaccurate results. In other words, when detecting the expansion force of a battery using a thin-film pressure sensor, directly determining the expansion force based on the original signal and calibration information is inaccurate. The method for detecting battery expansion force provided in the first embodiment of this invention, after obtaining the original signal, corrects it by combining calibration information with temperature information and response time to obtain a corrected signal. Since this corrected signal avoids the influence of temperature and response time, more accurate expansion force information can be obtained using the corrected signal and calibration information. Since the original signal quantity can be corrected by using correction information and temperature information to correct the influence of temperature on the electrical signal quantity, the original signal quantity can be corrected by this method under different ambient temperatures. In other words, the battery expansion force information obtained by this method is not affected by the ambient temperature of the battery, and has high practicality and versatility.

[0040] Understandably, the acquisition of temperature information is mainly for correcting the temperature drift of the raw signal output by the thin-film pressure sensor. Since the thin-film pressure sensor is set to the battery under test, the temperature information in this embodiment can be the temperature of the battery under test, the temperature of the thin-film pressure sensor, or the ambient temperature of the thin-film pressure sensor.

[0041] In this embodiment, the expansion force information can be the sum of the expansion forces acting on the thin-film pressure sensor, the distribution of the expansion forces acting on the thin-film pressure sensor, or a combination of both. This invention does not impose any specific limitations.

[0042] Understandably, different batteries have slightly different performance and structures. When using a thin-film pressure sensor to detect the expansion force of a battery over a long period, these differences often have varying effects on the sensor. To further improve the accuracy of battery expansion force detection results, this embodiment establishes a correspondence between the battery under test and the calibration information. That is, for different batteries under test, calibration information corresponding to the battery should be selected to correct the original signal, thus further improving the accuracy of the battery expansion force detection. The correspondence between the battery under test and the calibration information can be derived experimentally. Specifically, by experimentally verifying the performance of the thin-film pressure sensor under different environmental factors, calibration information corresponding to each environmental factor can be obtained. These environmental factors can include the battery's operating environment, the setup of the thin-film pressure sensor and the battery, etc.

[0043] Since different batteries have different identification information, their specific type can be identified through this information. The battery identification information can be the battery model or serial number. As one implementation method, in this embodiment, calibration information corresponding to the battery under test is obtained based on the model of the battery under test. Therefore, the specific steps for obtaining the calibration information are as follows:

[0044] Obtain the calibration information corresponding to the battery under test based on the battery model.

[0045] Please see Figure 3 Furthermore, in this embodiment, the correction information includes temperature drift correction information and time drift correction information. The specific steps for correcting the original signal quantity based on the temperature information, response time, and correction information to obtain the corrected signal quantity are as follows: the original signal quantity is corrected based on the temperature information and temperature drift correction information to obtain a first corrected signal quantity; the first corrected signal quantity is corrected based on the response time and time drift correction information to obtain the corrected signal quantity.

[0046] Of course, in other embodiments, the original signal quantity can be corrected first using time drift correction information, and then temperature correction can be performed using temperature drift correction information to obtain the corrected signal quantity.

[0047] Specifically, the temperature drift correction information stores the correction model Q and the calibration temperature. The correction model Q is determined based on the relationship between the signal output from the thin-film pressure sensor and temperature, and the calibration temperature is a preset temperature value. The specific steps for correcting the original signal based on the temperature information and the temperature drift correction information are as follows:

[0048] The original signal is corrected based on the temperature information and the correction model Q to obtain the first corrected signal corresponding to the calibration temperature.

[0049] Understandably, the ambient temperature of a thin-film pressure sensor will affect the magnitude of the signal it outputs when under pressure. In other words, under different ambient temperatures, when a thin-film pressure sensor is subjected to the same compressive force, the signal output of the thin-film pressure sensor may be different.

[0050] Please see Figure 4 For example, when a compressive force F1 is applied to a thin-film pressure sensor, the trend of the output signal of the thin-film pressure sensor with temperature is shown by curve L1; when a compressive force F2 is applied to the thin-film pressure sensor, the trend of the output signal with temperature is shown by curve L2; and when a compressive force F3 is applied to the thin-film pressure sensor, the trend of the output signal with temperature is shown by curve L3. By analyzing these curves, the relationship between the output signal of the thin-film pressure sensor and temperature can be obtained.

[0051] As one implementation method, the calibration model Q can be obtained through the following experimental approach:

[0052] Under different ambient temperatures, a pressure of F4 was applied to the thin-film pressure sensor, and the variation of the output signal of the thin-film pressure sensor with temperature was obtained, as shown in Table 1. The data in Table 1 can be used to create an optimization model to calculate the relationship between temperature and signal quantity within a certain temperature range under F4 pressure, thus obtaining the correction model Q.

[0053] Table 1

[0054] Temperature / °C -10 -5 0 5 25 40 60 semaphore 300 350 400 450 500 550 600

[0055] Of course, as another implementation, the pressure can be varied to obtain the signal output of the thin-film pressure sensor as a function of temperature when a pressure of F5 is applied to the thin-film pressure sensor at different ambient temperatures; the signal output of the thin-film pressure sensor as a function of temperature when a pressure of F6 is applied to the thin-film pressure sensor at different ambient temperatures; and the signal output of the thin-film pressure sensor as a function of temperature when a pressure of F7 is applied to the thin-film pressure sensor at different ambient temperatures. Here, F5, F6, and F7 represent pressures of different magnitudes. By creating an optimization model, the relationship between temperature and signal output within a certain temperature range under pressure F5 is calculated. Based on the calibration temperature, a correction model Q5 corresponding to different temperatures is obtained. Similarly, correction models Q6 and Q7 corresponding to different temperatures under pressure F6 and pressure F7 can be obtained. Then, correction models Q5, Q6, and Q7 are fitted to obtain a fitted correction model, which is the correction model Q.

[0056] Of course, the calibration model Q can also be obtained through other experimental methods. The above methods are only examples and are not the only limitations.

[0057] Since the effect of temperature on the signal output of a thin-film pressure sensor is independent of the battery type, the correction model Q can be applied to different types of batteries when detecting the magnitude of battery expansion force.

[0058] Understandably, when acquiring the expansion force information of the battery under test, this information is obtained by comparing the calibrated signal with the calibration information, which is a file obtained from the prior calibration of the thin-film pressure sensor. Since the ambient temperature of the thin-film pressure sensor affects the magnitude of its output signal, the calibration temperature should be as close as possible to the ambient temperature during the calibration of the thin-film pressure sensor when correcting for temperature drift in the original signal.

[0059] In this embodiment, as one implementation method, the thin-film pressure sensor is calibrated within a set temperature range to obtain calibration information. The calibration temperature is a temperature value within the set temperature range. For example, the ambient temperature when calibrating the thin-film pressure sensor is between 25°C and 30°C, that is, the set temperature range is 25°C to 30°C. Since the thin-film pressure sensor is less affected by temperature within this range, the calibration temperature can be any temperature within the set temperature range, that is, the calibration temperature can be 25°C, 27°C, or 30°C.

[0060] In this embodiment, as another implementation method, the calibration temperature is the temperature value at which the thin-film pressure sensor is calibrated to obtain calibration information. For example, if the ambient temperature during the calibration of the thin-film pressure sensor is 25°C, then the calibration temperature is also 25°C.

[0061] Furthermore, the time drift correction information includes the correspondence between the correction model K and the response time of the thin-film pressure sensor, wherein the correction model K is determined based on the change of the signal quantity output by the thin-film pressure sensor over time. In this embodiment, the specific steps for correcting the first correction signal quantity according to the response time and the time drift correction information to obtain the corrected signal quantity are as follows: the first correction signal quantity is corrected according to the correction model K and the response time to obtain the corrected signal quantity.

[0062] The response time can be the total time for the thin-film pressure sensor to start and be used, or it can be the total time for the signal output by the thin-film pressure sensor to exceed a set signal threshold. This invention does not impose any specific limitations.

[0063] Understandably, the response time of a thin-film pressure sensor will affect the magnitude of the signal it outputs when subjected to pressure. In other words, when a thin-film pressure sensor is subjected to the same compressive force, the signal output may differ depending on the duration of the compressive force.

[0064] Please see Figure 5 For example, when a pressure of F8 is continuously applied to a diaphragm pressure sensor, the change in the output signal of the diaphragm pressure sensor with the response time is shown by curve L8; when a pressure of F9 is continuously applied to the diaphragm pressure sensor, the change in the output signal of the diaphragm pressure sensor with the response time is shown by curve L9. By analyzing these curves, the relationship between the output signal of the diaphragm pressure sensor and the response time can be obtained.

[0065] As one implementation method, the calibration model K can be obtained through the following experimental approach:

[0066] Under the first preset condition, the battery was charged and discharged multiple times. The expansion force of the battery during charging and discharging was obtained through a pressure detection device, and the signal output of the thin-film pressure sensor at the corresponding time was also obtained. The signal output of the thin-film pressure sensor when the pressure detection device detected the same expansion force at different times was obtained, and the relationship between the signal output of the thin-film pressure sensor and time under the same expansion force was obtained, as shown in Table 2 below. Then, based on this relationship, the equation of the change of the signal output of the thin-film pressure sensor with the response time was obtained, and this equation is the correction model K.

[0067] Table 2

[0068] Time / h 1 10 50 150 200 250 300 semaphore 300 310 330 360 400 450 510

[0069] As another implementation method, multiple variation equations corresponding to different expansion forces can be obtained, and these variation equations can be fitted to obtain the fitted variation equation, which is the correction model K.

[0070] Of course, the calibration model K can also be obtained through other experimental methods. The above methods are only examples and are not the only limitations.

[0071] In this embodiment, the first preset condition is the environmental condition corresponding to the battery under test, which may be the ambient temperature of the battery under test, the initial clamping pressure on the battery under test, etc. The preset condition is set to simulate the real usage scenario of the battery under test.

[0072] In this embodiment, by performing the above experiment with different types of batteries, a calibration model K corresponding to the battery type can be obtained.

[0073] It should be noted that during each of the above experiments, the ambient temperature of the battery must be maintained within a certain temperature range. This can avoid temperature drift of the thin-film pressure sensor caused by changes in ambient temperature, and further ensure the accuracy of the calibration model K.

[0074] Understandably, in this embodiment, the calibration model K represents the relationship between response time and signal quantity, and the calibration model Q represents the relationship between temperature and signal quantity. The calibration model K or the calibration model Q is obtained based on specific experimental data. It may be a specific value or a specific equation function, as long as it can reflect their respective relationship.

[0075] The method for detecting battery expansion force provided in this embodiment corrects for temperature and time drift in the raw signal output by the thin-film pressure sensor. By using the corrected signal and calibration information, the expansion force of the battery under test can be determined to obtain more accurate battery expansion force information. Then, based on the battery expansion force information, the safety status of the battery can be judged more accurately.

[0076] It should be understood that the order of description of each step in the above embodiments does not imply 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 this application.

[0077] Please see Figure 6 The second embodiment of the present invention also provides a battery safety detection device. The battery safety detection device obtains the battery expansion force by using the method of detecting battery expansion force in the first embodiment. The method of detecting battery expansion force and its beneficial effects in the first embodiment have been described above and will not be repeated here.

[0078] The battery safety testing device includes a data acquisition unit, an expansion force detection unit, and a safety testing unit. The data acquisition unit and the expansion force detection unit are communicatively connected. The data acquisition unit includes at least a temperature sensor and a thin-film pressure sensor. The temperature sensor acquires temperature information, and the thin-film pressure sensor outputs a raw signal when compressed by the battery under test. The expansion force detection unit calibrates the raw signal based on the temperature information, the usage time of the thin-film pressure sensor, and calibration information to obtain a calibrated signal. It then determines the expansion force information of the battery under test based on the calibrated signal and calibration information. The safety testing unit determines the safety of the battery under test based on the expansion force information.

[0079] As one implementation method, the correction information can be stored in the expansion force detection unit, and the expansion force detection unit can directly retrieve the correction information when correcting the original signal quantity.

[0080] In another implementation, the calibration information can be stored in the cloud, and the expansion force detection unit communicates with the cloud. When calibrating the original signal, the cloud responds to the expansion force detection unit, and the expansion force detection unit acquires the calibration information corresponding to the identity information of the battery under test.

[0081] Similarly, calibration information can also be stored in the expansion force detection unit or in the cloud.

[0082] Furthermore, when the aforementioned battery safety detection device is applied to new energy vehicles, as one implementation, the data acquisition unit and the expansion force detection unit can be communicatively connected to the vehicle battery management system (BMS) of the new energy vehicle; as another implementation, the vehicle battery management system of the new energy vehicle is equipped with an expansion force detection unit, and the vehicle battery management system is communicatively connected to the data acquisition unit.

[0083] Please see Figure 7 The third embodiment of the present invention also provides a battery safety detection system. The battery safety detection system obtains the battery expansion force by using the method of detecting battery expansion force in the first embodiment. The method of detecting battery expansion force and its beneficial effects in the first embodiment have been described above and will not be repeated here.

[0084] Specifically, the battery safety testing system includes a terminal device and a cloud device. The terminal device is equipped with the battery under test, a temperature sensor, and a thin-film pressure sensor. The cloud device stores calibration and adjustment information corresponding to the thin-film pressure sensor. The terminal device is configured to acquire and send test data of the battery under test to the cloud device. The test data includes temperature information and the raw signal output from the thin-film pressure sensor. The cloud device is configured to receive the test data, determine the expansion force information of the battery under test based on the test data, calibration and adjustment information, and determine the safety of the battery under test based on the expansion force information.

[0085] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0086] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0087] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0088] In the embodiments provided in this application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0089] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0090] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0091] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by hardware related to computer program instructions. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0092] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for detecting battery expansion force, characterized in that, The method is applicable to the process of detecting the expansion force of a battery using a thin-film pressure sensor, and the method includes: Determine the calibration information corresponding to the battery under test; Acquire the detection data of the battery under test, the detection data including temperature information and the raw signal output by the thin-film pressure sensor; Obtain the response time of the thin-film pressure sensor; The original signal quantity is corrected based on the temperature information, the response time, and the correction information to obtain the corrected signal quantity. The expansion force information of the battery under test is determined based on the corrected signal quantity and calibration information, wherein the calibration information contains a preset correspondence between the signal quantity and the expansion force. The correction information includes temperature drift correction information and time drift correction information; the response time is the total time for the thin-film pressure sensor to start and use, or the total time for the signal output by the thin-film pressure sensor to exceed a set signal threshold. The specific steps for correcting the original signal based on the temperature information, the response time, and the correction information to obtain the corrected signal are as follows: The original signal quantity is corrected based on the temperature information and the temperature drift correction information to obtain a first corrected signal quantity; The first correction signal is corrected based on the response duration and the time drift correction information to obtain the corrected signal.

2. The method according to claim 1, characterized in that, The battery under test has a corresponding relationship with the calibration information. The specific steps for obtaining the calibration information are as follows: Obtain the calibration information corresponding to the battery under test based on the battery model.

3. The method according to claim 1, characterized in that, The temperature information is the temperature of the battery under test; or, the temperature information is the temperature of the thin-film pressure sensor; or, the temperature information is the ambient temperature of the thin-film pressure sensor.

4. The method according to claim 1, characterized in that, The temperature drift correction information stores a correction model Q and a calibration temperature. The correction model Q is determined based on the relationship between the signal output from the thin-film pressure sensor and temperature. The calibration temperature is a preset temperature value. The specific steps for correcting the original signal based on the temperature information and the temperature drift correction information are as follows: The original signal quantity is corrected based on the temperature information and the correction model Q to obtain the first corrected signal quantity corresponding to the calibration temperature.

5. The method according to claim 4, characterized in that, The calibration information is obtained by calibrating the thin-film pressure sensor within a set temperature range, where the calibration temperature is the temperature value within the set temperature range.

6. The method according to claim 4, characterized in that, The calibration temperature is the temperature value at which the thin-film pressure sensor is calibrated and the calibration information is obtained.

7. The method according to claim 1, characterized in that, The time drift correction information includes the correspondence between the correction model K and the response time of the thin-film pressure sensor, wherein the correction model K is determined based on the relationship between the signal quantity output by the thin-film pressure sensor and time. The specific steps for correcting the first corrected signal based on the response duration and the time drift correction information to obtain the corrected signal are as follows: The first correction signal is corrected according to the correction model K and the response duration to obtain the corrected signal.

8. The method according to claim 7, characterized in that, The response time is the total duration during which the signal output by the thin-film pressure sensor exceeds a set signal threshold.

9. A battery safety testing device, characterized in that, The device includes a data acquisition unit, an expansion force detection unit, and a safety detection unit; The data acquisition unit includes a temperature sensor and a thin-film pressure sensor. The temperature sensor is used to acquire temperature information, and the thin-film pressure sensor outputs the raw signal quantity when squeezed by the battery under test. The expansion force detection unit is used to correct the original signal quantity according to the response time of the thin-film pressure sensor, the temperature information and the correction information to obtain the corrected signal quantity, and to determine the expansion force information of the battery under test according to the corrected signal quantity and the calibration information. The safety detection unit is used to determine the safety of the battery under test based on the expansion force information. The correction information includes temperature drift correction information and time drift correction information; the response time is the total time for the thin-film pressure sensor to start and use, or the total time for the signal output by the thin-film pressure sensor to exceed a set signal threshold. The specific steps for correcting the original signal based on the temperature information, the response time, and the correction information to obtain the corrected signal are as follows: The original signal quantity is corrected based on the temperature information and the temperature drift correction information to obtain a first corrected signal quantity; The first correction signal is corrected based on the response duration and the time drift correction information to obtain the corrected signal.

10. The battery safety testing device according to claim 9, characterized in that, The correction information is preset in the expansion force detection unit; or, the correction information is stored in the cloud, and the expansion force detection unit communicates with the cloud to obtain the correction information.

11. A battery safety detection system, characterized in that, It includes terminal devices and cloud devices. The terminal devices include a battery under test, a temperature sensor, and a thin-film pressure sensor. The cloud devices have preset calibration information and standardization information corresponding to the thin-film pressure sensor. The terminal device is configured to acquire and send the detection data of the battery under test to the cloud device, the detection data including temperature information and the raw signal output by the thin-film pressure sensor; The cloud device is configured to: receive the detection data, determine the expansion force information of the battery under test based on the detection data, the correction information and the calibration information, and determine the safety of the battery under test based on the expansion force information; The process of acquiring and sending the detection data of the battery under test to the cloud device, wherein the detection data includes temperature information and the raw signal output by the thin-film pressure sensor, includes: determining calibration information corresponding to the battery under test; acquiring the detection data of the battery under test, wherein the detection data includes temperature information and the raw signal output by the thin-film pressure sensor; and acquiring the response time of the thin-film pressure sensor. The step of determining the expansion force information of the battery under test based on the detection data, the correction information, and the calibration information, and determining the safety of the battery under test based on the expansion force information, includes: The original signal quantity is corrected based on the temperature information, the response time, and the correction information to obtain the corrected signal quantity. The expansion force information of the battery under test is determined based on the corrected signal quantity and calibration information, wherein the calibration information contains a preset correspondence between the signal quantity and the expansion force. The correction information includes temperature drift correction information and time drift correction information; the response time is the total time for the thin-film pressure sensor to start and use, or the total time for the signal output by the thin-film pressure sensor to exceed a set signal threshold. The specific steps for correcting the original signal based on the temperature information, the response time, and the correction information to obtain the corrected signal are as follows: The original signal quantity is corrected based on the temperature information and the temperature drift correction information to obtain a first corrected signal quantity; The first correction signal is corrected based on the response duration and the time drift correction information to obtain the corrected signal.

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