Method and device for comprehensively evaluating safety of deep-sea pressure-resistant lithium battery cell

Abstract

The invention provides a safety comprehensive evaluation method and device for a deep-sea pressure-resistant lithium battery cell, and belongs to the technical field of battery detection, and the method comprises the steps: carrying out the pressure loading and releasing test of a to-be-detected deep-sea pressure-resistant lithium battery cell in a pressure environment; acquiring voltage data, temperature data and deformation data of the to-be-detected deep-sea voltage-resistant lithium battery monomer in the voltage applying and releasing test process; and based on the voltage data, the temperature data and the deformation data, determining the danger level of the to-be-detected deep-sea voltage-withstanding lithium battery cell. By detecting the voltage data, the temperature data and the deformation data of the deep-sea voltage-withstanding lithium battery monomer, the safety of the deep-sea voltage-withstanding lithium battery monomer can be comprehensively evaluated, and the danger level is given, so that when the deep-sea voltage-withstanding lithium battery monomer has a fault, professionals can deal with the fault in time, and the safety of the deep-sea voltage-withstanding lithium battery monomer is improved. The use risk of the deep-sea pressure-resistant lithium battery monomer in a deep-sea pressure environment is greatly reduced, and the use safety of the deep-sea pressure-resistant lithium battery monomer is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery detection, and in particular to a method and device for comprehensively evaluating the safety of a deep-sea pressure-resistant lithium battery monomer. Background Art

[0002] Deep-sea pressure-resistant lithium battery cells need to work for days or even months under extreme pressure (up to 115MPa). Ultra-high pressure may cause a short circuit inside the deep-sea pressure-resistant lithium battery cell, resulting in a sharp drop in voltage, rapid heating of the deep-sea pressure-resistant lithium battery cell, and subsequent severe swelling, endangering system safety. Therefore, it is necessary to conduct a safety assessment on the deep-sea pressure-resistant lithium battery cell before it is put into use to ensure safety in actual application.

[0003] At present, the following two methods are commonly used to evaluate the safety of deep-sea pressure-resistant lithium battery cells: one is to predict the performance of the battery through the change of the open-circuit voltage of the deep-sea pressure-resistant lithium battery cells; the other is to detect the swelling of the deep-sea pressure-resistant lithium battery cells through strain gauges. Both methods only use one signal to judge the state of the battery cell, which has a certain false alarm rate and the judgment of the battery cell state is inaccurate. In addition, there is no unified standard to characterize the safety level of the battery, that is, it is impossible to achieve a comprehensive evaluation of the battery cell state.

[0004] Therefore, there is an urgent need to provide a comprehensive safety assessment method and device for deep-sea pressure-resistant lithium battery cells, which can be used to accurately assess the safety level of deep-sea pressure-resistant lithium battery cells operating in a deep-sea environment. Summary of the invention

[0005] In view of this, it is necessary to provide a comprehensive safety assessment method and device for deep-sea pressure-resistant lithium battery cells to solve the technical problem that the prior art uses one signal to judge the state of the battery cell and there is no unified standard to characterize the safety level of the battery, resulting in the inability to accurately assess the safety level of the lithium battery cell.

[0006] On the one hand, in order to solve the above technical problems, the present invention provides a comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells, comprising: Conduct pressure-adding and pressure-removing tests on the deep-sea pressure-resistant lithium battery cells to be tested in a pressure environment; Acquiring voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure increase and decrease test; The danger level of the deep-sea pressure-resistant lithium battery cell to be inspected is determined based on the voltage data, the temperature data and the deformation data.

[0007] In a possible implementation, the pressure increase and reduction test includes: Pressurizing the deep-sea pressure-resistant lithium battery cell to be tested placed in a pressure environment at a preset pressurization rate; When the pressure after pressurization is equal to the preset pressure, the pressure is maintained for the preset time; The deep-sea pressure-resistant lithium battery cell to be tested placed in a pressure environment is depressurized at a preset depressurization rate.

[0008] In a possible implementation, the preset pressurization rate and the preset pressure relief rate are both less than or equal to 0.8 MPa / min, and the preset time length is greater than or equal to 30 minutes.

[0009] In a possible implementation, the voltage data includes a voltage drop value, the temperature data includes a temperature change value, and the deformation data includes a deformation amount; then determining the danger level of the deep-sea pressure-resistant lithium battery cell to be detected based on the voltage data, the temperature data, and the deformation data includes: Determine whether the pressure drop value is greater than a pressure drop threshold, whether the temperature change value is greater than a temperature change threshold, and whether the deformation amount is greater than a deformation amount threshold; When the voltage drop value is greater than the voltage drop threshold, or the temperature change value is greater than the temperature change threshold, or the deformation amount is greater than the deformation amount threshold, the danger level of the deep-sea pressure-resistant lithium battery cell to be detected is level three; When the voltage drop value is greater than the voltage drop threshold and the temperature change value is greater than the temperature change threshold, or the voltage drop value is greater than the voltage drop threshold and the deformation is greater than the deformation threshold, or the temperature change value is greater than the temperature change threshold and the deformation is greater than the deformation threshold, the danger level of the deep-sea pressure-resistant lithium battery cell to be detected is level 2; When the voltage drop value is greater than the voltage drop threshold, the temperature change value is greater than the temperature change threshold, and the deformation amount is greater than the deformation amount threshold, the danger level of the deep-sea pressure-resistant lithium battery cell to be detected is level one; Among them, the danger levels of level one, level two and level three gradually decrease.

[0010] In a possible implementation, the method further includes: During the pressure increase and decrease test, when the danger level of the deep-sea pressure-resistant lithium battery cell to be tested is level 2 or level 1, the test is stopped and the deep-sea pressure-resistant lithium battery cell to be tested is removed from the pressure environment.

[0011] In a possible implementation, the deep-sea pressure-resistant lithium battery cell to be tested is a soft-pack battery.

[0012] In a possible implementation, the method further includes: Conduct pressure-addition and pressure-removal tests on lithium iron phosphate battery cells placed in a pressure environment; Acquire comparative voltage data, comparative temperature data and comparative deformation data of the lithium iron phosphate battery cell during the pressure addition and release test; Determine a comparative hazard level of the lithium iron phosphate battery cell based on the comparative voltage data, the comparative temperature data and the comparative deformation data; The reliability of the deep-sea pressure-resistant lithium battery cell to be tested is verified based on the compared hazard level and the hazard level.

[0013] On the other hand, the present invention also provides a deep-sea pressure-resistant lithium battery monomer safety comprehensive evaluation device, comprising: A pressure test unit is used to perform pressure tests on the deep-sea pressure-resistant lithium battery cells to be tested in a pressure environment; A multi-dimensional data acquisition unit, used to acquire voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure increase and decrease test; A danger level determination unit is used to determine the danger level of the deep-sea pressure-resistant lithium battery cell to be tested based on the voltage data, the temperature data and the deformation data.

[0014] On the other hand, the present invention also provides a lithium battery safety assessment, including a memory and a processor, wherein: The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps in the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells described in any one of the possible implementation methods mentioned above.

[0015] On the other hand, the present invention also provides a computer-readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps in the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells described in any one of the above possible implementation methods are implemented.

[0016] The beneficial effects of the present invention are as follows: the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery monomers provided by the present invention simulates the deep-sea environment by performing pressure-adding and unloading tests in a pressure environment, and obtains the voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery monomer to be tested during the pressure-adding and unloading tests. Compared with the single-dimensional voltage or deformation data in the prior art, the data in three dimensions of voltage, temperature and deformation can more comprehensively characterize the state of the deep-sea pressure-resistant lithium battery monomer to be tested, and improve the comprehensiveness and accuracy of the detection of deep-sea pressure-resistant lithium battery monomers. In addition, the present invention determines the danger level of the deep-sea pressure-resistant lithium battery monomer to be tested based on voltage data, temperature data and deformation data, obtains the danger level by integrating the data in three dimensions, and evaluates the safety of the deep-sea pressure-resistant lithium battery monomer by the danger level, thereby improving the intuitiveness of the safety assessment.

[0017] Furthermore, the present invention determines the danger level of the deep-sea pressure-resistant lithium battery cell to be tested and determines the safety of the deep-sea pressure-resistant lithium battery cell according to the danger level, thereby ensuring the safe and stable operation of the deep-sea pressure-resistant lithium battery cell in a deep-sea pressure environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A schematic flow chart of an embodiment of a method for comprehensive safety assessment of a deep-sea pressure-resistant lithium battery provided by the present invention; Figure 2 A schematic structural diagram of an embodiment of the arrangement positions of the temperature detection device, the deformation detection device, and the voltage detection device provided by the present invention; Figure 3 A schematic diagram of a flow chart of an embodiment of a pressure increase and reduction test provided by the present invention; Figure 4 For the present invention Figure 1 A schematic flow chart of an embodiment of step S103; Figure 5 A schematic diagram of an embodiment of the process for verifying the reliability of a deep-sea pressure-resistant lithium battery cell to be tested provided by the present invention; Figure 6 A schematic diagram of the structure of an embodiment of a device for comprehensive safety assessment of a deep-sea pressure-resistant lithium battery provided by the present invention; Figure 7 A schematic structural diagram of an embodiment of the lithium battery safety assessment device provided by the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0021] It should be understood that the schematic drawings are not drawn to scale. The flowchart used in the present invention shows the operations implemented according to some embodiments of the present invention. It should be understood that the operations of the flowchart can be implemented out of order, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present invention, can add one or more other operations to the flowchart, and can also remove one or more operations from the flowchart. Some of the block diagrams shown in the accompanying drawings are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor systems and / or microcontroller systems.

[0022] Reference to an "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] The present invention provides a method and device for comprehensive safety assessment of a deep-sea pressure-resistant lithium battery cell, which are described below.

[0024] Figure 1 A schematic diagram of an embodiment of the comprehensive safety assessment of a deep-sea pressure-resistant lithium battery provided by the present invention is shown in FIG. Figure 1 As shown in the figure, the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery monomers includes: S101, performing pressure-adding and pressure-removing tests on the deep-sea pressure-resistant lithium battery cells to be tested placed in a pressure environment; S102, obtaining voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure increase and decrease test; S103, determining the danger level of the deep-sea pressure-resistant lithium battery cell to be tested based on the voltage data, temperature data and deformation data.

[0025] In order to obtain voltage data, temperature data and deformation data during the pressure loading and unloading test, in a specific embodiment of the present invention, before step S101, a temperature detection device, a deformation detection device and a voltage detection device need to be installed on the deep-sea pressure-resistant lithium battery cell to be tested. During the pressure loading and unloading test, the voltage data, temperature data and deformation data are obtained in real time through the temperature detection device, the deformation detection device and the voltage detection device.

[0026] Specifically, the temperature detection device is a temperature sensor, the voltage detection device is a voltage sensor, and the deformation detection device is a strain gauge.

[0027] In a specific embodiment of the present invention, the temperature detection device, the deformation detection device, and the voltage detection device are arranged at positions such as Figure 2 As shown, the two ends of the voltage detection device are respectively connected to the positive and negative electrodes of the deep-sea pressure-resistant lithium battery monomer to be detected. The temperature detection device and the deformation monitoring device are arranged in the middle of the deep-sea pressure-resistant lithium battery monomer to be detected.

[0028] It should be noted that: since the deep-sea pressure-resistant lithium battery to be tested has a certain volume, in order to achieve the accuracy of temperature data, such as Figure 2 As shown, the temperature is detected by three temperature detection devices, and the temperature average of the detection results of the three temperature detection devices is used as the temperature data of the deep-sea pressure-resistant lithium battery cell to be detected.

[0029] In order to improve the accuracy of the acquired temperature, deformation and voltage data, the detection accuracy of the temperature detection device, deformation detection device and voltage detection device should meet the requirements. Specifically, the accuracy of the voltage detection device should not be less than 1mV.

[0030] Among them, the deep-sea pressure-resistant lithium battery cell can be any one of a lithium primary battery or a lithium-ion battery.

[0031] Compared with the prior art, the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells provided in the embodiment of the present invention simulates the deep-sea environment by performing pressure-adding and unloading tests in a pressure environment, and obtains the voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cells to be tested during the pressure-adding and unloading tests. Compared with the single-dimensional voltage or deformation data in the prior art, the data in three dimensions of voltage, temperature and deformation can more comprehensively characterize the state of the deep-sea pressure-resistant lithium battery cells to be tested, and improve the comprehensiveness and accuracy of the detection of deep-sea pressure-resistant lithium battery cells. In addition, the embodiment of the present invention determines the danger level of the deep-sea pressure-resistant lithium battery cells to be tested based on the voltage data, temperature data and deformation data, obtains the danger level by integrating the data in three dimensions, and evaluates the safety of the deep-sea pressure-resistant lithium battery cells according to the danger level, thereby improving the intuitiveness of the safety assessment.

[0032] Furthermore, the embodiments of the present invention determine the danger level of the deep-sea pressure-resistant lithium battery cell to be tested, and determine the safety of the deep-sea pressure-resistant lithium battery cell according to the danger level, thereby ensuring the safe and stable operation of the deep-sea pressure-resistant lithium battery cell in a deep-sea pressure environment.

[0033] In some embodiments of the present invention, Figure 3 As shown, the pressure test includes: S301, pressurizing the deep-sea pressure-resistant lithium battery cell to be tested placed in a pressure environment at a preset pressurization rate; S302, when the pressure after pressurization is equal to the preset pressure, the pressure is maintained for a preset time; S303, depressurizing the deep-sea pressure-resistant lithium battery cell to be tested placed in a pressure environment at a preset depressurization rate.

[0034] It should be noted that the purpose of the pressure test is to simulate the deep-sea environment. Therefore, the various parameters in the pressure test need to be set according to the deep-sea environment.

[0035] In a specific embodiment of the present invention, the preset pressurization rate and the preset pressure relief rate are both less than or equal to 0.8 MPa / min, and the preset time length is greater than or equal to 30 minutes.

[0036] The preset pressure is any value between 0 and 115 MPa.

[0037] When a deep-sea pressure-resistant lithium battery cell is under ultra-high pressure, an internal short circuit will occur. At this time, the voltage, temperature and deformation data are specifically manifested as: the voltage drops sharply, the temperature rises rapidly, and then a serious swelling phenomenon occurs (large deformation). That is, the voltage, temperature and deformation data focus on the voltage drop, temperature change value and deformation.

[0038] Therefore, the voltage data includes the voltage drop value, the temperature data includes the temperature change value, and the deformation data includes the deformation amount; then Figure 4 As shown, step S103 includes: S401, determining whether the pressure drop value is greater than a pressure drop threshold, whether the temperature change value is greater than a temperature change threshold, and whether the deformation amount is greater than a deformation amount threshold; S402: When the voltage drop value is greater than the voltage drop threshold, or the temperature change value is greater than the temperature change threshold, or the deformation amount is greater than the deformation amount threshold, the hazard level of the deep-sea pressure-resistant lithium battery to be tested is level three; S403, when the voltage drop value is greater than the voltage drop threshold and the temperature change value is greater than the temperature change threshold, or the voltage drop value is greater than the voltage drop threshold and the deformation is greater than the deformation threshold, or the temperature change value is greater than the temperature change threshold and the deformation is greater than the deformation threshold, the hazard level of the deep-sea pressure-resistant lithium battery to be tested is level 2; S404, when the voltage drop value is greater than the voltage drop threshold, the temperature change value is greater than the temperature change threshold, and the deformation amount is greater than the deformation amount threshold, the hazard level of the deep-sea pressure-resistant lithium battery to be tested is level one; Among them, the danger levels of level one, level two and level three gradually decrease.

[0039] In other words, when one of the parameters among the pressure drop value, temperature change value and deformation amount is greater than the corresponding threshold value, the danger level is the lighter level one; when any two of the parameters among the pressure drop value, temperature change value and deformation amount are greater than the corresponding threshold value, the danger level is the second level; when all three parameters among the pressure drop value, temperature change value and deformation amount are greater than the corresponding threshold value, the danger level is the most serious level one.

[0040] In a specific embodiment of the present invention, the voltage drop threshold is 2mV, and the temperature change threshold is 10° C. Theoretically, when the deep-sea pressure-resistant lithium battery cell to be detected swells, the internal resistance of the strain gauge is infinite. Therefore, the deformation amount can be specifically set according to the actual application scenario, which will not be elaborated here.

[0041] Since when the hazard level of the deep-sea pressure-resistant lithium battery monomer to be tested is level 2 or level 1, the deep-sea pressure-resistant lithium battery monomer to be tested may be damaged, which may cause leakage of chemical substances and cause safety problems. In order to avoid this problem, in some embodiments of the present invention, the comprehensive safety assessment method of the deep-sea pressure-resistant lithium battery monomer further includes: During the pressure test, when the danger level of the deep-sea pressure-resistant lithium battery cell to be tested is level two or level one, the test is stopped and the deep-sea pressure-resistant lithium battery cell to be tested is removed from the pressure environment.

[0042] The embodiment of the present invention stops the test when the danger level of the deep-sea pressure-resistant lithium battery cell to be tested is level two or level one, thereby avoiding further damage to the deep-sea pressure-resistant lithium battery cell to be tested and causing leakage of chemical substances, ensuring the safety of the testers during the test and avoiding pollution to the pressure environment.

[0043] Since soft-pack batteries have the characteristics of flexible design, light weight, small internal resistance, not easy to explode, many cycles, good safety performance, large capacity, high energy density, etc., in a preferred embodiment of the present invention, the deep-sea pressure-resistant lithium battery cell to be tested is a soft-pack battery.

[0044] In order to verify the reliability of the deep-sea pressure-resistant lithium battery cell to be tested, in some embodiments of the present invention, Figure 5 As shown, the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery monomers also includes: S501, performing pressure addition and removal tests on lithium iron phosphate battery cells placed in a pressure environment; S502, obtaining comparative voltage data, comparative temperature data and comparative deformation data of the lithium iron phosphate battery cell during the pressure addition and removal test; S503, determining the comparative hazard level of the lithium iron phosphate battery cell based on the comparative voltage data, the comparative temperature data and the comparative deformation data; S504. Verify the reliability of the deep-sea pressure-resistant lithium battery cell to be tested based on the comparison of the hazard level and the hazard level.

[0045] Compared with deep-sea pressure-resistant lithium battery cells, conventional lithium iron phosphate battery cells have poor pressure resistance. Therefore, under the same pressure-loading and unloading test conditions, the danger level of the comparison danger level should be higher than the danger level. Based on this, step S504 is specifically: judging whether the danger level is greater than the comparison danger level. If it is greater, the reliability of the deep-sea pressure-resistant lithium battery cell to be tested is higher.

[0046] Furthermore, the comparison voltage data, the comparison temperature data and the comparison deformation data should all be greater than the voltage data, the temperature data and the deformation data.

[0047] In a specific embodiment of the present invention, a 62Ah deep-sea pressure-resistant lithium iron phosphate battery cell (referred to as cell A) and a 55Ah conventional lithium iron phosphate battery cell (referred to as cell B) are taken and pressure-added and pressure-unloaded tests are performed respectively, and the batteries are in a fully charged state. The specific pressure-added and pressure-unloaded test process is as follows: The first step is to place monomer A and monomer B in a pressure environment respectively, start the pressurization system, and pressurize at a rate of 2MPa / min; Step 2: When the pressure reaches 60MPa, maintain the pressure for 30 minutes; Step 3: Unload to normal pressure at a rate of 2MPa / min.

[0048] During the pressure increase and decrease process, the voltage, temperature and deformation of monomer A and monomer B are tested. The test results are shown in Table 1: Table 1 Test results

[0049] Among them, the danger level of monomer A is " / ", which means that the pressure drop value is less than the pressure drop threshold, the temperature change value is less than the temperature change threshold, and the deformation amount is less than the deformation amount threshold.

[0050] It can be seen from Table 1 that compared with lithium iron phosphate battery cells, deep-sea pressure-resistant lithium battery cells have better pressure resistance performance.

[0051] To sum up, the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells provided in the embodiment of the present invention can comprehensively assess the safety of battery cells by detecting the voltage, temperature, deformation and other signals of the deep-sea pressure-resistant lithium battery cells, and give a danger level, so that professionals can deal with it in time when the battery fails, which greatly reduces the risk of using deep-sea pressure-resistant lithium battery cells in deep-sea pressure environments and further improves the safety of using deep-sea pressure-resistant lithium battery cells.

[0052] In order to better implement the deep-sea pressure-resistant lithium battery monomer safety comprehensive assessment method in the embodiment of the present invention, based on the deep-sea pressure-resistant lithium battery monomer safety comprehensive assessment method, the embodiment of the present invention also provides a deep-sea pressure-resistant lithium battery monomer safety comprehensive assessment device, such as Figure 6 As shown, the deep-sea pressure-resistant lithium battery single-cell safety comprehensive evaluation device 600 includes: The pressure test unit 601 is used to perform pressure test on the deep-sea pressure-resistant lithium battery cell to be tested in a pressure environment; The multi-dimensional data acquisition unit 602 is used to acquire the voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure test; The danger level determination unit 603 is used to determine the danger level of the deep-sea pressure-resistant lithium battery cell to be tested based on the voltage data, temperature data and deformation data.

[0053] It should be noted that the deep-sea pressure-resistant lithium battery cell comprehensive safety assessment device 600 provided in the above embodiment can implement the technical solution described in the above-mentioned deep-sea pressure-resistant lithium battery cell comprehensive safety assessment method embodiment. The specific implementation principles or specific implementation details of the above-mentioned modules or units can refer to the corresponding contents in the above-mentioned deep-sea pressure-resistant lithium battery cell comprehensive safety assessment method embodiment, and will not be elaborated here one by one.

[0054] like Figure 7 As shown, the present invention also provides a lithium battery safety assessment device 700. The lithium battery safety assessment device 700 includes a processor 701, a memory 702 and a display 703. Figure 7 Only some components of the lithium battery safety assessment device 700 are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0055] In some embodiments, the processor 701 can be a central processing unit (CPU), a microprocessor or other data processing chip, which is used to run the program code or process data stored in the memory 702, such as the comprehensive safety assessment method of deep-sea pressure-resistant lithium battery cells in the present invention.

[0056] In some embodiments of the present invention, the processor 701 may be a single server or a server group. The server group may be centralized or distributed. In some embodiments, the processor 701 may be local or remote. In some embodiments, the processor 701 may be implemented in a cloud platform. In one embodiment, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an internal cloud, a multi-cloud, etc., or any combination thereof.

[0057] In some embodiments, the memory 702 may be an internal storage unit of the lithium battery safety assessment device 700 , such as a hard disk or memory of the lithium battery safety assessment device 700 .

[0058] Furthermore, the memory 702 may include both an internal storage unit and an external storage device of the lithium battery safety evaluation device 700. The memory 702 is used to store application software installed in the lithium battery safety evaluation device 700 and various data.

[0059] In some embodiments, the display 703 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch device, etc. The display 703 is used to display information of the lithium battery safety assessment device 700 and to display a visual user interface. The components 701-703 of the lithium battery safety assessment device 700 communicate with each other through a system bus.

[0060] In some embodiments of the present invention, when the processor 701 executes the deep-sea pressure-resistant lithium battery single-cell safety comprehensive assessment program in the memory 702, the following steps may be implemented: Conduct pressure-adding and pressure-removing tests on the deep-sea pressure-resistant lithium battery cells to be tested in a pressure environment; Obtaining voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure increase and decrease test; The hazard level of the deep-sea pressure-resistant lithium battery cell to be tested is determined based on voltage data, temperature data and deformation data.

[0061] It should be understood that: when the processor 701 executes the deep-sea pressure-resistant lithium battery single cell safety comprehensive assessment program in the memory 702, in addition to the above functions, other functions can also be implemented. For details, please refer to the description of the corresponding method embodiment above.

[0062] Correspondingly, an embodiment of the present invention also provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, the steps or functions in the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells provided in the above-mentioned method embodiments can be implemented.

[0063] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware (such as a processor, a controller, etc.) through a computer program, and the computer program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0064] The above is a detailed introduction to a method and device for comprehensive safety assessment of a deep-sea pressure-resistant lithium battery cell provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for technical personnel in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A comprehensive safety assessment method for deep-sea pressure-resistant lithium battery monomers, characterized in that: include: Conduct pressure-adding and pressure-removing tests on the deep-sea pressure-resistant lithium battery cells to be tested in a pressure environment; Acquiring voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure increase and decrease test; The danger level of the deep-sea pressure-resistant lithium battery cell to be inspected is determined based on the voltage data, the temperature data and the deformation data.

2. The method for comprehensive safety assessment of deep-sea pressure-resistant lithium battery monomers according to claim 1, characterized in that: The pressure test includes: Pressurizing the deep-sea pressure-resistant lithium battery cell to be tested placed in a pressure environment at a preset pressurization rate; When the pressure after pressurization is equal to the preset pressure, the pressure is maintained for the preset time; The deep-sea pressure-resistant lithium battery cell to be tested placed in a pressure environment is depressurized at a preset depressurization rate.

3. The method for comprehensive safety assessment of deep-sea pressure-resistant lithium battery monomers according to claim 2 is characterized in that: The preset pressurization rate and the preset pressure relief rate are both less than or equal to 0.8 MPa / min, and the preset time length is greater than or equal to 30 minutes.

4. The method for comprehensive safety assessment of deep-sea pressure-resistant lithium battery monomers according to claim 1, characterized in that: The voltage data includes a voltage drop value, the temperature data includes a temperature change value, and the deformation data includes a deformation amount; then determining the danger level of the deep-sea pressure-resistant lithium battery cell to be detected based on the voltage data, the temperature data and the deformation data includes: Determine whether the pressure drop value is greater than a pressure drop threshold, whether the temperature change value is greater than a temperature change threshold, and whether the deformation amount is greater than a deformation amount threshold; When the voltage drop value is greater than the voltage drop threshold, or the temperature change value is greater than the temperature change threshold, or the deformation amount is greater than the deformation amount threshold, the danger level of the deep-sea pressure-resistant lithium battery cell to be detected is level three; When the voltage drop value is greater than the voltage drop threshold and the temperature change value is greater than the temperature change threshold, or the voltage drop value is greater than the voltage drop threshold and the deformation is greater than the deformation threshold, or the temperature change value is greater than the temperature change threshold and the deformation is greater than the deformation threshold, the danger level of the deep-sea pressure-resistant lithium battery cell to be detected is level 2; When the voltage drop value is greater than the voltage drop threshold, the temperature change value is greater than the temperature change threshold, and the deformation amount is greater than the deformation amount threshold, the danger level of the deep-sea pressure-resistant lithium battery cell to be detected is level one; Among them, the danger levels of level one, level two and level three gradually decrease.

5. The method for comprehensive safety assessment of deep-sea pressure-resistant lithium battery monomers according to claim 4, characterized in that: The method further comprises: During the pressure increase and decrease test, when the danger level of the deep-sea pressure-resistant lithium battery cell to be tested is level 2 or level 1, the test is stopped and the deep-sea pressure-resistant lithium battery cell to be tested is removed from the pressure environment.

6. The method for comprehensive safety assessment of deep-sea pressure-resistant lithium battery monomers according to claim 1, characterized in that: The deep-sea pressure-resistant lithium battery monomer to be tested is a soft-pack battery.

7. The method for comprehensive safety assessment of deep-sea pressure-resistant lithium battery monomers according to claim 1, characterized in that: The method further comprises: Conduct pressure-addition and pressure-removal tests on lithium iron phosphate battery cells placed in a pressure environment; Acquire comparative voltage data, comparative temperature data and comparative deformation data of the lithium iron phosphate battery cell during the pressure addition and release test; Determine a comparative hazard level of the lithium iron phosphate battery cell based on the comparative voltage data, the comparative temperature data and the comparative deformation data; The reliability of the deep-sea pressure-resistant lithium battery cell to be tested is verified based on the compared hazard level and the hazard level.

8. A comprehensive safety assessment device for deep-sea pressure-resistant lithium battery cells, characterized in that: include: A pressure test unit is used to perform pressure tests on the deep-sea pressure-resistant lithium battery cells to be tested in a pressure environment; A multi-dimensional data acquisition unit, used to acquire voltage data, temperature data and deformation data of the deep-sea pressure-resistant lithium battery cell to be tested during the pressure increase and decrease test; A danger level determination unit is used to determine the danger level of the deep-sea pressure-resistant lithium battery cell to be tested based on the voltage data, the temperature data and the deformation data.

9. A lithium battery safety assessment device, characterized in that: comprising a memory and a processor, wherein: The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps in the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program or instruction, and when the program or instruction is executed by the processor, the steps in the comprehensive safety assessment method for deep-sea pressure-resistant lithium battery cells described in any one of claims 1 to 7 are implemented.

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