Battery module heat insulation pad type selection method and test system
By incrementally increasing the thermal insulation capacity of the thermal insulation pads in the battery module, thermal runaway is triggered and the propagation stop point is determined, which solves the problems of high cost and long cycle of thermal insulation pad selection and realizes efficient thermal insulation pad evaluation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING YIWEI LITHIUM ENERGY CO LTD
- Filing Date
- 2025-12-26
- Publication Date
- 2026-05-01
AI Technical Summary
Existing methods for selecting thermal insulation pads suffer from high testing costs and long testing cycles.
By increasing the thermal insulation capacity of the thermal insulation pads in the battery module along the direction away from the target cell, thermal runaway of the target cell is triggered, and the thermal insulation pad that meets the thermal insulation requirements is selected according to the location where the thermal runaway propagation stops.
This technology enables the evaluation of the thermal insulation performance of multiple insulation pads through a single test, saving sample costs and testing fees, shortening development time, and improving testing efficiency.
Smart Images
Figure CN121955071A_ABST
Abstract
Description
Battery Module Thermal Insulation Pad Selection Method and Testing System Technical Field
[0001] This application relates to the field of battery technology, and in particular to a method for selecting and testing a heat insulation pad for a battery module. Background Technology
[0002] To select the most effective thermal insulation pad from multiple candidates, related technologies typically involve fabricating multiple test modules for each candidate pad and then conducting thermal runaway tests on each module. By comparing the temperature rise data of adjacent cells and whether thermal runaway was triggered in multiple independent thermal runaway tests, the thermal insulation pad that meets the insulation requirements is selected. However, this method of thermal insulation pad selection suffers from high testing costs and long testing cycles. Summary of the Invention
[0003] This application provides a method and testing system for selecting heat insulation pads for battery modules, aiming to solve the problems of high testing costs and long testing cycles in related technologies for selecting heat insulation pads.
[0004] To achieve the above objectives, according to a first aspect of this application, a method for selecting heat insulation pads for a battery module is provided, comprising: obtaining a battery module to be tested, the battery module to be tested including a plurality of battery cells and a plurality of heat insulation pads, the plurality of battery cells being spaced apart along a first direction, and a heat insulation pad being disposed between any two adjacent battery cells, the plurality of battery cells including a target battery cell, and the heat insulation capacity of the plurality of heat insulation pads being progressively increased along the direction away from the target battery cell in the first direction, the heat insulation capacity being determined by the thickness and / or heat insulation coefficient of the heat insulation pads. The process involves: triggering thermal runaway of the target battery cell; determining the location where thermal runaway propagation stops along a direction away from the target battery cell; and selecting a thermal insulation pad that meets the insulation requirements based on the thermal runaway propagation stop location. Optionally, selecting a thermal insulation pad that meets the insulation requirements based on the thermal runaway propagation stop location includes: determining that the thermal runaway propagation stop location and a plurality of thermal insulation pads on the side away from the target battery cell in the first direction all meet the insulation requirements; and selecting the thermal insulation pad located at the thermal runaway propagation stop location as the target thermal insulation pad from among the plurality of thermal insulation pads that meet the insulation requirements.
[0005] Optionally, before triggering the thermal runaway of the target cell, the method further includes: acquiring a pressurizing device; and applying pressure to the battery module through the pressurizing device.
[0006] Optionally, triggering the thermal runaway of the target battery cell includes: acquiring a triggering device; and triggering the thermal runaway of the target battery cell through the triggering device.
[0007] Optionally, the triggering device includes a heating module or a charging module.
[0008] Optionally, each of the battery cells has multiple state parameters, and determining the location where thermal runaway propagation stops along the direction away from the target battery cell includes: determining a first battery cell that has experienced thermal runaway and a second battery cell that has not experienced thermal runaway based on at least one of the state parameters, wherein the first battery cell and the second battery cell are adjacent along the direction away from the target battery cell; and determining the thermal insulation pad between the first battery cell and the second battery cell as the location where thermal runaway propagation stops.
[0009] Optionally, the state parameters include smoke generation state, and determining the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway based on at least one of the state parameters includes: determining that the first battery cell has experienced thermal runaway when the first battery cell is in a smoke generation state; and determining that the second battery cell has not experienced thermal runaway when the second battery cell is not in a smoke generation state.
[0010] Optionally, the state parameter includes the output voltage, and determining the first cell that has experienced thermal runaway and the second cell that has not experienced thermal runaway based on at least one of the state parameters includes: determining that the first cell has experienced thermal runaway when the output voltage of the first cell is 0V; and determining that the second cell has not experienced thermal runaway when the output voltage of the second cell is greater than 0V.
[0011] Optionally, the state parameters include temperature and temperature rise rate. Determining the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway based on at least one of the state parameters includes: determining that the first battery cell has experienced thermal runaway when the temperature of the first battery cell is greater than or equal to a temperature threshold and / or the temperature rise rate of the first battery cell is greater than 3°C / s for multiple consecutive times; determining that the second battery cell has not experienced thermal runaway when the temperature of the second battery cell is less than a first temperature threshold and the temperature rise rate of the second battery cell is less than 3°C / s for multiple consecutive times.
[0012] Optionally, the thickness of the plurality of heat insulation pads is progressively increased along the direction away from the target cell in the first direction; and / or, the heat insulation coefficient of the plurality of heat insulation pads is progressively increased along the direction away from the target cell in the first direction.
[0013] According to a second aspect of this application, a testing system is provided for performing the battery module thermal insulation pad selection method as described above, the testing system comprising: a support platform for supporting the battery module to be tested; and a triggering device for triggering thermal runaway of the target cell.
[0014] Optionally, it also includes a pressurizing device, which is disposed on the support platform and is used to apply pressure to the battery module to be tested.
[0015] Optionally, it further includes: an acquisition module, the acquisition module being used to acquire parameter information of a plurality of the cells along a direction away from the target cell; and a control module, the control module being adapted to determine the location where thermal runaway propagation stops along the direction away from the target cell based on the plurality of parameter information.
[0016] Optionally, the acquisition module includes multiple temperature sensors, each of which is configured to correspond one-to-one with one of the battery cells, and each temperature sensor is used to detect the temperature of the corresponding battery cell; and / or, the acquisition module includes multiple voltage sensors, each of which is configured to correspond one-to-one with one of the battery cells, and each voltage sensor is used to detect the output voltage of the corresponding battery cell.
[0017] In the battery module thermal insulation pad selection method of this application embodiment, the thermal insulation capacity of multiple thermal insulation pads increases progressively along the direction away from the target cell in the first direction. When thermal runaway of the target cell is triggered, the thermal runaway of the target cell can propagate along the direction away from the target cell. By determining the stopping position of thermal runaway propagation along the direction away from the target cell, a thermal insulation pad that meets the thermal insulation requirements can be selected based on the stopping position of thermal runaway propagation. The battery module thermal insulation pad selection method of this application can simultaneously test the thermal insulation performance of multiple thermal insulation pads in a single test, saving sample costs, testing fees, and development time, and greatly improving testing efficiency.
[0018] Other features and advantages of this application will be described in detail in the following detailed description section. The accompanying drawings are provided to more clearly illustrate the technical solutions in the embodiments of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.
[0019] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.
[0020] Figure 1 is a structural schematic diagram of the battery module provided in an exemplary embodiment of this disclosure; Figure 2 is an enlarged schematic diagram of part A in Figure 1; Figure 3 is a flowchart of one of the battery module heat insulation pad selection methods provided in an exemplary embodiment of this disclosure; Figure 4 is a detailed flowchart of step S600 in Figure 3; Figure 5 is another flowchart of the battery module heat insulation pad selection method provided in an exemplary embodiment of this disclosure; Figure 6 is a detailed flowchart of step S400 in Figure 3; Figure 7 is a detailed flowchart of step S500 in Figure 3; Figure 8 is a structural schematic diagram of the test system provided in an exemplary embodiment of this disclosure; Figure 9 is a structural schematic diagram of the test system shown in Figure 8 with the battery module installed.
[0021] Explanation of reference numerals in the attached drawings: 10, battery module; 11, battery cell; 12, heat insulation pad; 20, testing system; 21, support platform; 22, triggering device; 23, pressurizing device; 24, acquisition module. Detailed Implementation
[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.
[0023] This application provides a method for selecting a heat insulation pad for a battery module. Please refer to Figures 1 to 3. Figure 1 is a structural schematic diagram of a battery module provided in an exemplary embodiment of this disclosure; Figure 2 is an enlarged schematic diagram of part A in Figure 1; Figure 3 is one of the flowcharts of the method for selecting a heat insulation pad for a battery module provided in an exemplary embodiment of this disclosure. The method for selecting a heat insulation pad for a battery module includes the following steps: Step S100: Obtain a battery module 10 to be tested. The battery module 10 to be tested includes multiple battery cells 11 and multiple heat insulation pads 12. The multiple battery cells 11 are spaced apart along a first direction. A heat insulation pad 12 is provided between any two adjacent battery cells 11. The multiple battery cells 11 include a target battery cell. The heat insulation capacity of the multiple heat insulation pads 12 increases incrementally along the direction away from the target battery cell in the first direction. The heat insulation capacity is characterized by the thickness and / or heat insulation coefficient of the heat insulation pad 12.
[0024] It should be noted that the method of increasing the heat insulation capacity of the plurality of heat insulation pads 12 along the direction away from the target cell in the first direction can be selected as needed. For example, in one embodiment, the thickness of the plurality of heat insulation pads 12 increases along the direction away from the target cell in the first direction. In another embodiment, the heat insulation coefficient of the plurality of heat insulation pads 12 increases along the direction away from the target cell in the first direction.
[0025] Step S400: Trigger thermal runaway of the target cell.
[0026] It should be noted that when the target battery cell experiences thermal runaway, the thermally runaway battery cell 11 exhibits several characteristics, including the temperature of the battery cell 11 rising to above 300°C, the generation of smoke by the battery cell 11, and the output voltage of the battery cell 11 being 0V. Of course, in other embodiments, the thermally runaway battery cell 11 may have other characteristics, which are not limited in this application.
[0027] Step S500: Determine the location where thermal runaway propagation stops along the direction away from the target cell.
[0028] Step S600: Select a thermal insulation pad 12 that meets the thermal insulation requirements based on the location where thermal runaway propagation stops.
[0029] It should be noted that when the heat insulation pad 12 meets the heat insulation requirements, it means that the heat transmitted by the thermal runaway cell 11 through the heat insulation pad 12 cannot cause the cell 11 adjacent to the thermal runaway cell 11 to experience thermal runaway, thereby blocking the propagation of thermal runaway.
[0030] In the battery module thermal insulation pad selection method of this application embodiment, since the thermal insulation capacity of multiple thermal insulation pads 12 is progressively increased along the direction away from the target cell in the first direction, when thermal runaway of the target cell is triggered, the thermal runaway of the target cell can propagate along the direction away from the target cell. By determining the stopping position of thermal runaway propagation along the direction away from the target cell, a thermal insulation pad 12 that meets the thermal insulation requirements can be selected based on the stopping position of thermal runaway propagation. The battery module thermal insulation pad selection method of this application can test the thermal insulation performance of multiple thermal insulation pads 12 simultaneously in one test, saving sample costs, testing fees and development time, and greatly improving testing efficiency.
[0031] Specifically, referring to Figure 4, which is a schematic diagram of the specific process of step S600 in Figure 3, step S600, selecting the heat insulation pad 12 that meets the heat insulation requirements based on the location where thermal runaway propagation stops, includes: step S610, determining that the location where thermal runaway propagation stops and that multiple heat insulation pads 12 that are far away from the target cell side in the first direction all meet the heat insulation requirements.
[0032] In this step, since the thermal insulation pad 12 at the location where thermal runaway propagation stops can prevent thermal runaway from continuing to propagate away from the target cell, it can be determined that the thermal insulation pad 12 at the location where thermal runaway propagation stops meets the thermal insulation requirements. Furthermore, the thermal insulation performance of the thermal insulation pad 12 located at the location where thermal runaway propagation stops, away from the target cell in the first direction, is superior to that of the thermal insulation pad 12 at the location where thermal runaway propagation stops. Therefore, the thermal insulation pad 12 located at the location where thermal runaway propagation stops, away from the target cell in the first direction, also meets the thermal insulation requirements.
[0033] Step S620: Select the heat insulation pad 12 that is in the position where thermal runaway propagation has stopped from among the multiple heat insulation pads 12 that meet the heat insulation requirements as the target heat insulation pad 12.
[0034] In this step, the thermal insulation pad 12, located at the point where thermal runaway propagation has stopped, is a critical insulation solution that meets the requirement of "not triggering thermal runaway of adjacent cells 11". The thermal insulation pad 12, located at the point where thermal runaway propagation has stopped, has low production cost and is easy to manufacture. Selecting the thermal insulation pad 12 located at the point where thermal runaway propagation has stopped as the target thermal insulation pad 12 achieves the goal of meeting insulation requirements while reducing production difficulty and saving production costs.
[0035] Of course, in other embodiments, the thermal insulation pad 12 located away from the target cell in the first direction from the thermal runaway propagation cessation position can also be selected as the target thermal insulation pad 12. Specifically, this application does not limit this.
[0036] Referring to Figure 5, which is a second flowchart of the battery module thermal insulation pad selection method provided in an exemplary embodiment of this disclosure; specifically, before step 400 and triggering thermal runaway of the target cell, the method further includes: step 200, obtaining the pressurization device 23.
[0037] In this step, the type of pressurizing device 23 can be selected as needed. For example, the pressurizing device 23 may include a servo electric press, a pneumatic pressurizing system, or a hydraulic pressurizing system. Specifically, this application does not limit this.
[0038] Step 300: Apply pressure to the battery module 10 using the pressurizing device 23.
[0039] In this step, pressure is applied to the battery module 10 by the pressurizing device 23 to ensure that the extrusion pressure applied to the battery module 10 by the pressurizing device 23 remains constant throughout the entire selection process, regardless of any changes that occur inside the battery module 10, thereby simulating the mechanical environment that a real battery pack would experience during thermal runaway.
[0040] Referring to Figure 6, which is a schematic diagram of the specific process of step S400 in Figure 3; specifically, step S400, triggering thermal runaway of the target cell, includes: step S410, acquiring the triggering device 22.
[0041] It should be noted that there are various types of triggering devices 22. For example, triggering device 22 may include a heating module or a charging module. Of course, in other embodiments, triggering device 22 may also include a needle penetration testing device. Specifically, this application does not limit the type of triggering device 22.
[0042] Step S420: Trigger thermal runaway of the target cell by triggering device 22.
[0043] It should be noted that when the target cell is triggered by the triggering device 22 to achieve thermal runaway, the temperature of the target cell rises. The heat from the target cell can be transferred to the adjacent cell 11 through the heat insulation pad 12. When the heat insulation performance of the heat insulation pad 12 does not meet the heat insulation requirements, a large amount of heat generated by the thermal runaway of the target cell will be transferred to the adjacent cell 11, thereby causing the cell 11 adjacent to the target cell to be triggered to achieve thermal runaway. This process is the propagation process of thermal runaway.
[0044] Referring to Figure 7, which is a schematic flowchart of step S500 in Figure 3, each battery cell 11 has multiple state parameters. Step S500, determining the stopping position of thermal runaway propagation along the direction away from the target battery cell, includes: step S510, determining the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway based on at least one state parameter. The first and second battery cells are adjacent along the direction away from the target battery cell. It should be noted that the multiple state parameters of the battery cell may include temperature, smoke generation state, current, voltage, temperature rise rate, etc. Furthermore, the method for determining the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway can be selected as needed. For example, the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway can be determined by manual observation. In other embodiments, the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway can also be determined by detection using a detection device.
[0045] Step S520: Determine the thermal insulation pad 12 between the first battery cell and the second battery cell as the location where thermal runaway propagation stops.
[0046] It should be noted that since the first battery cell experienced thermal runaway while the second battery cell did not, it can be determined that the thermal insulation pad 12 located between the first and second battery cells blocked the propagation of thermal runaway, thus identifying the thermal insulation pad 12 between the first and second battery cells as the location where the propagation of thermal runaway stopped.
[0047] Specifically, the state parameters include the smoke generation state. Step S510, which determines the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway based on at least one state parameter, includes: step S511a, when the first battery cell is in the smoke generation state, determining that the first battery cell has experienced thermal runaway; step S512a, when the second battery cell is not in the smoke generation state, determining that the second battery cell has not experienced thermal runaway.
[0048] In the above steps, when cell 11 experiences thermal runaway, it will generate smoke. Whether cell 11 has experienced thermal runaway can be determined by visually observing whether it is generating smoke. Therefore, when the first cell is generating smoke, it is determined that the first cell has experienced thermal runaway; when the second cell is not generating smoke, it is determined that the second cell has not experienced thermal runaway.
[0049] Specifically, the state parameters include the output voltage. Step S510, which determines the first cell that has experienced thermal runaway and the second cell that has not experienced thermal runaway based on at least one state parameter, includes: Step S511b, when the output voltage of the first cell is 0V, it is determined that the first cell has experienced thermal runaway.
[0050] Step S512b: When the output voltage of the second cell is greater than 0V, it is determined that the second cell has not experienced thermal runaway.
[0051] In the above steps, when cell 11 experiences thermal runaway, it can be determined that the output voltage of the thermally runaway cell 11 is 0V, while the output voltage of the cell 11 that has not experienced thermal runaway is greater than 0V. Based on this characteristic, when the output voltage of the first cell is 0V, it is determined that the first cell has experienced thermal runaway; when the output voltage of the second cell is greater than 0V, it is determined that the second cell has not experienced thermal runaway.
[0052] It should be noted that in other embodiments, when cell 11 experiences a voltage drop, and the voltage drop exceeds 25% of the initial voltage, it can also be determined that cell 11 has experienced thermal runaway. Specifically, this application does not limit this.
[0053] Specifically, the state parameters include temperature and temperature rise rate. Step S510, which determines the first cell that has thermal runaway and the second cell that has not thermal runaway based on at least one state parameter, includes: step S511c, when the temperature of the first cell is greater than or equal to a temperature threshold and / or the temperature rise rate of the first cell is greater than 3°C / s for multiple consecutive times, it is determined that the first cell has thermal runaway.
[0054] It should be noted that the temperature threshold can be selected as needed. In the embodiments of this application, the temperature threshold is 300°C. In other embodiments, the temperature threshold can be 295°C, 298°C, 301°C, or 305°C, etc. Specifically, this application does not limit it.
[0055] Step S511c: When the temperature of the second cell is less than the first temperature threshold and the rate of temperature rise of the second cell is less than 3℃ / s for multiple consecutive times, it is determined that the second cell has not experienced thermal runaway.
[0056] In the above steps, when cell 11 experiences thermal runaway, it can be determined that the temperature of the thermally runaway cell 11 is greater than a temperature threshold, and that the temperature rise rate of the thermally runaway cell 11 is greater than 3℃ / s for multiple consecutive cycles. Based on this characteristic, when the temperature of the first cell is greater than or equal to the temperature threshold, it is determined that the first cell has experienced thermal runaway; when the temperature rise rate of the first cell is greater than 3℃ / s for multiple consecutive cycles, it is determined that the first cell has experienced thermal runaway. When the temperature of the second cell is less than the first temperature threshold, and the temperature rise rate of the second cell is less than 3℃ / s for multiple consecutive cycles, it is determined that the second cell has not experienced thermal runaway.
[0057] It should be noted that when cell 11 experiences thermal runaway, its output voltage typically drops to 0V. Then, cell 11 experiences multiple consecutive temperature rise rates exceeding 3℃ / s, and almost simultaneously, it produces smoke. Subsequently, cell 11's temperature reaches its threshold. Therefore, the first cell experiencing thermal runaway and the second cell not experiencing thermal runaway can be determined simultaneously based on output voltage, temperature, temperature rise rate, and smoke generation status.
[0058] The following describes the selection method for the thermal insulation pad of a battery module using five battery cells 11 as an example. Multiple battery cells 11 arranged in a first direction away from the target battery cell include a target battery cell, a first battery cell, a second battery cell, a third battery cell, a fourth battery cell, and a fifth battery cell arranged sequentially. The thermal insulation pad 12 between the target battery cell and the first battery cell is the first thermal insulation pad 12; the thermal insulation pad 12 between the first and second battery cells is the second thermal insulation pad 12; the thermal insulation pad 12 between the second and third battery cells is the third thermal insulation pad 12; the thermal insulation pad 12 between the third and fourth battery cells is the fourth thermal insulation pad 12; and the thermal insulation pad 12 between the fourth and fifth battery cells is the fifth thermal insulation pad 12. A pressurizing device 23 is used to apply pressure to the battery module 10. A triggering device 22 is used to trigger thermal runaway of the target battery cell. When a target cell experiences thermal runaway and propagates, the process is as follows: the heat from the runaway target cell is transferred to the first cell via the first thermal insulation pad 12, triggering thermal runaway in the first cell; the heat from the runaway first cell is transferred to the second cell via the second thermal insulation pad 12, triggering thermal runaway in the second cell; the heat from the runaway second cell is transferred to the third cell via the third thermal insulation pad 12, triggering thermal runaway in the third cell; and so on. This process is the propagation of thermal runaway. When the heat from the runaway third cell is transferred to the fourth cell via the fourth thermal insulation pad 12, but does not trigger thermal runaway in the fourth cell, the propagation of thermal runaway stops. At this point, the fourth thermal insulation pad 12 is the location where the propagation of thermal runaway stops, and the corresponding fourth thermal insulation pad 12 meets the insulation requirements and is a critical insulation solution that satisfies the requirement of "not triggering thermal runaway in adjacent cells 11". Since the insulation capacity of the insulation pads 12 increases progressively in the first direction, the insulation performance of the fifth insulation pad 12 is superior to that of the fourth insulation pad 12. Therefore, it can be determined that both the fourth and fifth insulation pads 12 meet the insulation requirements. Ultimately, the more economical fourth insulation pad 12 can be selected as the target insulation pad 12.
[0059] Referring to Figures 8 and 9, Figure 8 is a structural schematic diagram of the test system provided in an exemplary embodiment of this disclosure; Figure 9 is a structural schematic diagram of the test system shown in Figure 8 with a battery module installed. According to a second aspect of this disclosure, a test system 20 is provided. This test system 20 is used to perform the battery module thermal insulation pad selection method as described above. The test system 20 includes a support platform 21 and a triggering device 22. The support platform 21 is used to support the battery module 10 to be tested, and the triggering device 22 triggers thermal runaway of the target battery cell. This makes the initiation of thermal runaway of the target battery cell more precise and controllable, and the operation is simple, reducing the operational risk of manually triggering thermal runaway of the target battery cell.
[0060] In one embodiment, the test system 20 further includes a pressurizing device 23, which is mounted on the support platform 21 and is used to apply pressure to the battery module 10 to be tested. Thus, by applying pressure to the battery module 10 through the pressurizing device 23, it is ensured that the compressive force applied by the pressurizing device 23 to the battery module 10 remains constant throughout the entire selection process, regardless of any changes occurring inside the battery module 10, thereby simulating the mechanical environment experienced by a real battery pack during thermal runaway.
[0061] In one embodiment, the test system 20 further includes an acquisition module 24 and a control module. The acquisition module 24 acquires parameter information of multiple cells 11 along the direction away from the target cell. The control module is adapted to determine the stopping position of thermal runaway propagation along the direction away from the target cell based on the multiple parameter information. Thus, by continuously and in real-time collecting parameter information (such as temperature, voltage, air pressure, and gas composition) of multiple cells 11 by the acquisition module 24, a comprehensive and objective data foundation is provided. The control module is adapted to automatically and accurately determine the stopping position of thermal runaway propagation along the direction away from the target cell based on the multiple parameter information. This design eliminates human error, achieves automated and accurate determination, and improves work efficiency.
[0062] In one embodiment, the acquisition module 24 includes multiple temperature sensors, each corresponding to one of the multiple battery cells 11. Each temperature sensor detects the temperature of its corresponding battery cell 11. Since thermal runaway is essentially a violent exothermic reaction within the battery cell 11, temperature is the most direct and crucial physical quantity characterizing the occurrence, propagation, and intensity of thermal runaway. By using an independent temperature sensor to monitor the temperature of each battery cell 11, it is easier to accurately determine the location where thermal runaway propagation stops.
[0063] In one embodiment, the acquisition module 24 includes multiple voltage sensors, each corresponding to one of the multiple battery cells 11. Each voltage sensor detects the output voltage of its corresponding battery cell 11. Thus, thermal runaway is typically caused by an internal short circuit, and its earliest and most direct manifestation is often an abnormal output voltage of the battery cell. By using an independent voltage sensor to monitor the output voltage of each battery cell 11, it is easier to accurately determine the location where thermal runaway propagation stops.
[0064] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0065] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0066] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.
[0067] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.
Claims
1. A method for selecting a heat insulation pad for a battery module, characterized in that, include: A battery module to be tested is obtained, the battery module to be tested includes multiple battery cells and multiple thermal insulation pads, the multiple battery cells are spaced apart along a first direction, and a thermal insulation pad is disposed between any two adjacent battery cells, the multiple battery cells include a target battery cell, and the thermal insulation capacity of the multiple thermal insulation pads increases incrementally along the direction away from the target battery cell in the first direction, the thermal insulation capacity being characterized by the thickness and / or thermal insulation coefficient of the thermal insulation pads; thermal runaway of the target battery cell is triggered; the location where thermal runaway propagation stops along the direction away from the target battery cell is determined; and thermal insulation pads that meet the thermal insulation requirements are selected according to the location where thermal runaway propagation stops.
2. The method for selecting a battery module heat insulation pad according to claim 1, characterized in that, The step of selecting the thermal insulation pad that meets the thermal insulation requirements based on the location where thermal runaway propagation stops includes: determining that the location where thermal runaway propagation stops and that multiple thermal insulation pads on the side away from the target cell in the first direction all meet the thermal insulation requirements; and selecting the thermal insulation pad located at the location where thermal runaway propagation stops from among the multiple thermal insulation pads that meet the thermal insulation requirements as the target thermal insulation pad.
3. The method for selecting a battery module heat insulation pad according to claim 1 or 2, characterized in that, Before triggering thermal runaway of the target cell, the process further includes: acquiring a pressurizing device; and applying pressure to the battery module through the pressurizing device.
4. The method for selecting a battery module heat insulation pad according to any one of claims 1 to 3, characterized in that, The process of triggering thermal runaway of the target battery cell includes: acquiring a triggering device; and triggering thermal runaway of the target battery cell through the triggering device.
5. The method for selecting a battery module heat insulation pad according to claim 4, characterized in that, The triggering device includes a heating module or a charging module.
6. The method for selecting a battery module heat insulation pad according to any one of claims 1 to 5, characterized in that, Each of the battery cells has multiple state parameters. Determining the location where thermal runaway propagation stops along the direction away from the target battery cell includes: determining a first battery cell that has experienced thermal runaway and a second battery cell that has not experienced thermal runaway based on at least one of the state parameters, wherein the first battery cell and the second battery cell are adjacent along the direction away from the target battery cell; and determining the thermal insulation pad between the first battery cell and the second battery cell as the location where thermal runaway propagation stops.
7. The method for selecting a battery module heat insulation pad according to claim 6, characterized in that, The state parameters include the smoke generation state. Determining the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway based on at least one of the state parameters includes: determining that the first battery cell has experienced thermal runaway when the first battery cell is in the smoke generation state; and determining that the second battery cell has not experienced thermal runaway when the second battery cell is not in the smoke generation state.
8. The method for selecting a battery module heat insulation pad according to claim 6, characterized in that, The state parameters include the output voltage. Determining the first cell that has experienced thermal runaway and the second cell that has not experienced thermal runaway based on at least one of the state parameters includes: determining that the first cell has experienced thermal runaway when the output voltage of the first cell is 0V; and determining that the second cell has not experienced thermal runaway when the output voltage of the second cell is greater than 0V.
9. The method for selecting a battery module heat insulation pad according to claim 6, characterized in that, The state parameters include temperature and temperature rise rate. Determining the first battery cell that has experienced thermal runaway and the second battery cell that has not experienced thermal runaway based on at least one of the state parameters includes: determining that the first battery cell has experienced thermal runaway when the temperature of the first battery cell is greater than or equal to a temperature threshold and / or the temperature rise rate of the first battery cell is greater than 3°C / s for multiple consecutive times; determining that the second battery cell has not experienced thermal runaway when the temperature of the second battery cell is less than a first temperature threshold and the temperature rise rate of the second battery cell is less than 3°C / s for multiple consecutive times.
10. The method for selecting a battery module heat insulation pad according to any one of claims 1 to 9, characterized in that, The thickness of the plurality of heat insulation pads increases in the first direction along the direction away from the target cell; and / or, the heat insulation coefficient of the plurality of heat insulation pads increases in the first direction along the direction away from the target cell.
11. A testing system for performing the battery module heat insulation pad selection method according to any one of claims 1 to 10, characterized in that, The testing system includes: a support platform for supporting the battery module to be tested; and a triggering device for triggering thermal runaway of the target cell.
12. The testing system according to claim 11, characterized in that, It also includes a pressurizing device, which is located on the support platform and is used to apply pressure to the battery module to be tested.
13. The testing system according to claim 11 or 12, characterized in that, Also includes: An acquisition module is used to acquire parameter information of a plurality of the battery cells along a direction away from the target battery cell; a control module is adapted to determine the location where thermal runaway propagation stops along the direction away from the target battery cell based on the plurality of parameter information.
14. The testing system according to claim 13, characterized in that, The acquisition module includes multiple temperature sensors, each of which is configured to correspond one-to-one with one of the battery cells, and each temperature sensor is used to detect the temperature of the corresponding battery cell; and / or, the acquisition module includes multiple voltage sensors, each of which is configured to correspond one-to-one with one of the battery cells, and each voltage sensor is used to detect the output voltage of the corresponding battery cell.