Air tightness testing methods and systems, controllers and computer-readable storage media

Abstract

This application provides an airtightness testing method and system, a controller, and a computer-readable storage medium. The airtightness testing method includes: placing a thermal management component within the housing space of a battery casing; evacuating the housing space to a negative pressure and detecting pressure changes within the housing space; evacuating the thermal management component to a vacuum and performing helium background detection on the thermal management component; filling the housing space with helium and detecting the helium leakage rate of the battery casing; and performing vacuum accumulation helium detection on the thermal management component. The technical solution of this application can improve the production efficiency of battery devices.

Description

Technical Field

[0001] This application relates to the field of airtightness testing technology, and more specifically, to an airtightness testing method and system, a controller, and a computer-readable storage medium. Background Technology

[0002] Currently, during the battery manufacturing process, airtightness testing of the casing and thermal management components is required. To adapt to the production cycle, the casing and thermal management components undergo high-temperature treatment before airtightness testing. However, because the positive pressure differential method is affected by temperature, the casing and thermal management components need to be cooled down before the airtightness test, resulting in a longer production cycle and impacting production efficiency. Summary of the Invention

[0003] This application provides an airtightness testing method and system, a controller, and a computer-readable storage medium, which can improve the production efficiency of battery devices.

[0004] This application is achieved through the following technical solution:

[0005] In a first aspect, embodiments of this application provide an airtightness testing method, comprising: placing a thermal management component in the housing space of a battery box; drawing a negative pressure into the housing space and detecting the pressure change within the housing space; drawing a vacuum into the thermal management component and performing helium background detection on the thermal management component; filling the housing space with helium and detecting the helium leakage rate of the battery box; and performing vacuum accumulation helium detection on the thermal management component.

[0006] According to the airtightness testing method of this application, the thermal management component is placed within the housing space of the battery box, allowing for simultaneous airtightness testing of both the battery box and the thermal management component. This reduces testing time and improves battery device production efficiency. Furthermore, helium is filled into the housing space for helium testing of the battery box. Simultaneously, the helium in the housing space is used for vacuum accumulation helium testing of the thermal management component, enabling the testing of the airtightness of high-temperature products with high accuracy and precision. Additionally, vacuum accumulation of the thermal management component can be performed simultaneously with helium testing of the battery box, reducing testing time and improving battery device production efficiency. The battery box and thermal management component can share the same helium mass spectrometer leak detector. After helium testing of the battery box is completed, helium testing of the thermal management component is performed, reducing testing costs and lowering manufacturing costs.

[0007] According to some embodiments of this application, filling the containment space with helium and detecting the helium leakage rate of the battery box includes: filling the containment space with helium multiple times, and extracting the gas in the containment space between two adjacent filling operations.

[0008] In the above scheme, by repeatedly filling the containment space with helium and extracting the gas from the containment space between two adjacent filling operations, the uniform speed of helium in the containment space can be accelerated, the equilibration time can be shortened, and the detection accuracy can be improved.

[0009] According to some embodiments of this application, before performing a vacuum accumulation helium test on the thermal management component, the method further includes: repeatedly extracting gas from the thermal management component, and filling the thermal management component with nitrogen gas between two adjacent gas extraction operations.

[0010] In the above scheme, by repeatedly extracting gas from the thermal management component and filling the thermal management component with nitrogen between two adjacent gas extraction actions, the thermal management component is made to breathe. This can amplify the defects in the thermal management component, increase the amount of helium leakage that leaks into the thermal management component through the defect location, and improve the detection accuracy.

[0011] According to some embodiments of this application, during the process of filling the containment space with helium and detecting the helium leakage rate of the battery box, the gas in the thermal management component is extracted multiple times simultaneously, and nitrogen is injected into the thermal management component between two adjacent gas extraction actions.

[0012] In the above scheme, since the helium testing time for the battery box is relatively long, the thermal management components are subjected to multiple gas extraction and helium filling operations while the helium testing of the battery box is being performed. This allows the airtightness testing of the battery box and the thermal management components to be carried out simultaneously during the helium testing waiting time of the battery box, thereby shortening the testing time of the battery device and improving the manufacturing efficiency of the battery device.

[0013] According to some embodiments of this application, after checking the helium leakage rate of the battery housing, a vacuum accumulation helium test is performed on the thermal management components.

[0014] In the above scheme, while performing helium gas testing on the battery box, the thermal management components located in the containment space are also tested using helium gas in a vacuum accumulation manner. This can shorten the airtightness testing time and improve the testing efficiency.

[0015] According to some embodiments of this application, after performing a vacuum accumulation helium test on the thermal management component, the helium gas in the containment space is extracted and the containment space is restored to atmospheric pressure; nitrogen gas is then introduced into the thermal management component and the internal pressure of the thermal management component is restored to atmospheric pressure.

[0016] In the above scheme, the helium in the containment space is extracted to realize the recycling of helium and reduce the pollution of helium to the environment; nitrogen is filled into the thermal management component and the internal pressure of the thermal management component is restored to atmospheric pressure. Nitrogen can reduce the oxidation and corrosion of the detection component by impurities such as oxygen and moisture.

[0017] According to some embodiments of this application, the method of drawing negative pressure into the containment space and detecting the pressure change within the containment space includes: drawing the pressure in the containment space to a first preset pressure value, stopping the drawing, letting it stand for a first preset time, and detecting the pressure change within the containment space. If the pressure change value of the containment space is greater than the preset value, the detection is stopped. If the pressure change value of the containment space is less than or equal to the preset value, helium is filled into the containment space, and the helium leakage rate of the battery box is detected.

[0018] In the above scheme, the pressure in the containment space is pumped down to a first preset pressure value, pumping is stopped, and the space is left to stand for a first preset time. The subsequent actions are determined based on the detected pressure change in the containment space. If the pressure change value in the containment space is greater than the preset value, it indicates that there is a defect in the battery box, and the test is stopped, and the battery box is judged as an unqualified product. If the pressure change value in the containment space is less than or equal to the preset value, it indicates that the battery box is qualified, helium is filled into the containment space, and micro-leakage detection is performed on the battery box.

[0019] According to some embodiments of this application, evacuating the thermal management component and performing helium background testing on the thermal management component includes: evacuating the pressure inside the thermal management component to a second preset pressure value, stopping the evacuation, allowing it to stand for a second preset time, and performing helium background testing on the thermal management component. If the helium background leakage rate is greater than a preset value, the testing is stopped; if the helium background leakage rate is less than or equal to the preset value, helium is filled into the containment space, and while detecting the helium leakage rate value of the battery box, vacuum accumulation helium testing is performed on the thermal management component.

[0020] In the above scheme, the pressure inside the thermal management component is evacuated to a second preset pressure value, the evacuation is stopped, and the component is left to stand for a second preset time. The background helium leakage rate of the thermal management component is then detected to improve the accuracy of the vacuum cumulative helium test. Based on the background helium leakage rate of the thermal management component, if the helium leakage rate is less than or equal to the preset value, the product is considered qualified, and the process of filling the containment space with helium continues, while the helium leakage rate of the battery box is detected, and the vacuum cumulative helium test of the thermal management component is performed. If the helium leakage rate is greater than the preset value, the thermal management component has a defect, the product is considered unqualified, and the testing is stopped.

[0021] Secondly, this application also provides a controller, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the airtightness detection method provided in the above embodiments.

[0022] Thirdly, this application also provides an airtightness detection system, which includes the controller provided in the above embodiments.

[0023] Fourthly, this application also provides a computer-readable storage medium storing computer-executable instructions for performing the airtightness detection method provided in the above embodiments.

[0024] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 A schematic flowchart illustrating an airtightness testing method provided in some embodiments of this application;

[0027] Figure 2 Schematic diagram of the airtightness testing device provided in some embodiments of this application;

[0028] Figure 3 A schematic diagram illustrating the negative pressure and vacuum stages provided in some embodiments of this application;

[0029] Figure 4 A schematic diagram illustrating the large leak detection and background detection stages provided for some embodiments of this application;

[0030] Figure 5 A schematic diagram illustrating the helium filling stage provided for some embodiments of this application;

[0031] Figure 6 A schematic diagram illustrating the respiratory replacement stage provided in some embodiments of this application;

[0032] Figure 7 A schematic diagram illustrating the detection stage provided for some embodiments of this application;

[0033] Figure 8 This is a schematic diagram of the battery casing testing process provided in some embodiments of this application;

[0034] Figure 9 This is a schematic diagram of the testing process for thermal management components provided in some embodiments of this application.

[0035] Icons: 100 - Battery housing; 110 - Storage space; 120 - Vent; 200 - Thermal management components; 210 - Inlet; 220 - Outlet; 11 - First vacuum pump; 12 - Second vacuum pump; 21 - First pipe; 22 - Second pipe; 23 - Third pipe; 24 - Fourth pipe; 25 - Fifth pipe; 26 - Sixth pipe; 27 - Seventh pipe; 28 - Eighth pipe; 29 - Ninth pipe; 30 - Tenth pipe; 31 - Eleventh pipe; 32 - Twelfth pipe; 41 - First solenoid valve; 42 - Second solenoid valve; 4 3-Third solenoid valve; 44-Fourth solenoid valve; 45-Fifth solenoid valve; 46-Sixth solenoid valve; 47-Seventh solenoid valve; 48-Eighth solenoid valve; 49-Ninth solenoid valve; 51-First pressure sensor; 52-Second pressure sensor; 53-First differential pressure leak detector; 54-Helium mass spectrometer leak detector; 55-Helium detection gun; 56-Third pressure sensor; 61-First pressure regulating valve; 62-Second pressure regulating valve; 63-Third pressure regulating valve; 71-Storage tank; 81-Helium gas source; 82-Nitrogen gas source; 83-Air gas source; 91-Robot arm. Detailed Implementation

[0036] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0037] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having" and any variations thereof in the description, claims and foregoing drawings of this application are intended to cover non-exclusive inclusion.

[0038] The terms "first," "second," etc., in the specification, claims, or the accompanying drawings of this application are used to distinguish different objects, rather than to describe a specific order or primary / secondary relationship.

[0039] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0040] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0041] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0042] In this application, "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0043] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0044] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells into a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0045] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.

[0046] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0047] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0048] As an example, the enclosure may include a first sub-enclosure and a second sub-enclosure. The first and second sub-enclosures are interlocked to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or shutting down; it can be sealed or not sealed. The first sub-enclosure may be a top cover or a bottom plate.

[0049] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0050] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0051] The battery device includes a thermal management component, which contains a fluid to regulate the temperature of the individual battery cells. This fluid can be a liquid or a gas, and temperature regulation refers to heating or cooling the individual battery cells. When cooling or lowering the temperature of the individual battery cells, the thermal management component contains a cooling fluid to reduce their temperature. In this case, the thermal management component can also be called a cooling component, a cooling system, or a cooling plate, and the fluid it contains can be called a cooling medium or cooling fluid, more specifically, a coolant or a cooling gas. Alternatively, the thermal management component can also be used to heat the individual battery cells. Optionally, the fluid can be circulating to achieve better temperature regulation. Optionally, the fluid can be water, a mixture of water and ethylene glycol, or air, etc.

[0052] The thermal management component can be a water-cooled plate, which is assembled with the battery cell assembly to regulate the temperature of the battery cell assembly. The water-cooled plate has an inner cavity and an opening communicating with the inner cavity to allow fluid to enter or exit the inner cavity.

[0053] During battery manufacturing, components with high airtightness requirements need to undergo airtightness testing, such as the battery casing and water-cooling plates. In the battery manufacturing production line, to adapt to the production cycle, airtightness tests are performed on the casing and water-cooling plates after the high-temperature treatment of the previous process (such as drying). Airtightness testing typically uses the positive pressure differential method, which involves filling the test component with high-pressure air, stabilizing it, and then measuring the pressure change within a preset time. However, because the positive pressure differential method is affected by temperature, the casing and thermal management components need to be cooled before airtightness testing, resulting in a long waiting time and a longer production cycle, thus affecting production efficiency.

[0054] In view of this, in order to solve the problem of low production efficiency caused by high temperature waiting, this application provides an airtightness detection method, including: placing the thermal management component in the housing space of the battery box; drawing a negative pressure into the housing space and detecting the pressure change in the housing space; drawing a vacuum into the thermal management component and performing helium background detection on the thermal management component; filling the housing space with helium and detecting the helium leakage rate value of the battery box; and performing vacuum accumulation helium detection on the thermal management component.

[0055] According to the airtightness testing method of this application, the thermal management component is placed within the housing space of the battery box, allowing for simultaneous airtightness testing of both the battery box and the thermal management component. This reduces testing time and improves battery device production efficiency. Furthermore, helium is filled into the housing space for helium testing of the battery box. Simultaneously, the helium in the housing space is used for vacuum accumulation helium testing of the thermal management component, enabling the testing of the airtightness of high-temperature products with high accuracy and precision. Additionally, vacuum accumulation of the thermal management component can be performed simultaneously with helium testing of the battery box, reducing testing time and improving battery device production efficiency. The battery box and thermal management component can share the same helium mass spectrometer leak detector. After helium testing of the battery box is completed, helium testing of the thermal management component is performed, reducing testing costs and lowering manufacturing costs.

[0056] The airtightness testing method of this application is described below with reference to the accompanying drawings.

[0057] Please refer to Figures 1 to 2 , Figure 1 This is a schematic flowchart illustrating the airtightness testing method provided in some embodiments of this application. Figure 2 The diagram shows a simplified structure of an airtightness testing device provided in some embodiments of this application. In a first aspect, embodiments of this application provide an airtightness testing method, including:

[0058] S100, the thermal management component 200 is placed in the receiving space 110 of the battery box 100;

[0059] S200, draws negative pressure into the containment space 110 and detects the pressure change within the containment space 110;

[0060] S300, evacuate the thermal management component 200, and perform helium background testing on the thermal management component 200;

[0061] S400: Fill the containment space 110 with helium and detect the helium leakage rate of the battery box 100.

[0062] S500 performs vacuum accumulation helium testing on thermal management component 200.

[0063] In some embodiments, please refer to Figure 2This application also provides an airtightness detection device, which includes a first vacuum pump 11, a second vacuum pump 12, a helium gas source 81, a first pressure sensor 51, a second pressure sensor 52, a first differential pressure leak detector 53, and a helium mass spectrometer leak detector 54. The first vacuum pump 11 is used to extract gas from the containment space 110; the second vacuum pump 12 is used to evacuate the thermal management component 200; the first differential pressure leak detector 53 is used to detect pressure changes in the containment space 110; the helium mass spectrometer leak detector 54 is used to perform helium background detection on the thermal management component 200 and helium detection on the battery box 100; the first pressure sensor 51 is used to detect the pressure in the containment space 110, and the second pressure sensor 52 is used to detect the pressure inside the thermal management component 200.

[0064] For example, in step "S100, placing the thermal management component 200 in the receiving space 110 of the battery box 100", after placing the thermal management component 200 in the receiving space 110 of the battery box 100, the battery box 100 is sealed, while retaining the vent 120 of the battery box 100 and the opening corresponding to the inlet 210 and outlet 220 of the thermal management component 200.

[0065] Step "S300, evacuate the thermal management component 200 and perform helium background detection on the thermal management component 200" can be performed synchronously with step "S200, draw negative pressure into the containment space 110 and detect pressure changes within the containment space 110". For example, a first vacuum pump 11 is connected to the vent 120 on the wall of the battery box 100, and negative pressure is drawn into the containment space 110 by the first vacuum pump 11; a second vacuum pump 12 is connected to the inlet 210 and outlet 220 of the thermal management component 200, and a vacuum is drawn into the thermal management component 200 by the second vacuum pump 12.

[0066] Step "S200, draw negative pressure into the accommodating space 110 and detect the pressure change in the accommodating space 110" is a large leak detection for the battery box 100, which is used to detect larger defects in the battery box 100.

[0067] Step "S300, evacuate the thermal management component 200 and perform helium background detection on the thermal management component 200" includes large leak detection and helium background leak rate detection of the thermal management component 200. After evacuation, the component is left to stand for a period of time, and the pressure change inside the thermal management component 200 is monitored. Then, helium background detection is performed on the thermal management component 200. Helium background detection refers to the calibration and control of the background helium concentration of the tested component during helium mass spectrometry leak detection. Its core purpose is to eliminate the interference of trace amounts of helium in the natural environment and ensure the accuracy of the leak detection results.

[0068] like Figure 2As shown, the vent 120 of the battery housing 100 is connected to the air inlet of the first vacuum pump 11 via a first pipe 21. The inlet 210 of the thermal management component 200 is connected to the air inlet of the second vacuum pump 12 via a second pipe 22, and the outlet 220 of the thermal management component 200 is connected to the air inlet of the second vacuum pump 12 via a third pipe 23. A first solenoid valve 41 is installed on the first pipe 21, positioned near the air inlet of the first vacuum pump 11; a second solenoid valve 42 is installed on the second pipe 22, positioned near the air inlet of the second vacuum pump 12; and a third solenoid valve 43 is installed on the third pipe 23, positioned near the air inlet of the second vacuum pump 12. The vent 120 of the battery housing 100 and the first differential pressure leak detector 53 are connected via a fourth pipe 24, and a fourth solenoid valve 44 is installed on the fourth pipe 24, positioned near the first differential pressure leak detector 53. The thermal management component 200 is connected to the inlet 210 and the helium mass spectrometer leak detector 54 via a fifth pipe 25. A fifth solenoid valve 45 is installed on the fifth pipe 25, and is positioned close to the helium mass spectrometer leak detector 54. The helium mass spectrometer leak detector 54 is connected to the helium detection suction gun 55 via a sixth pipe 26. A sixth solenoid valve 46 is installed on the sixth pipe 26, and is positioned close to the helium mass spectrometer leak detector 54.

[0069] All valves in this application are initially closed. For example, the first solenoid valve 41, the second solenoid valve 42, the third solenoid valve 43, the fourth solenoid valve 44, the fifth solenoid valve 45, and the sixth solenoid valve 46 are initially closed.

[0070] When performing step "S200, draw negative pressure into the containment space 110 and detect the pressure change in the containment space 110", the first solenoid valve 41 is opened, the first vacuum pump 11 is started, and the pressure value in the containment space 110 is detected by the first pressure sensor 51 located at the vent 120 of the battery box 100. When the pressure in the containment space 110 is detected to reach a preset value (such as 0~-5KPa), the pump stops, the first vacuum pump 11 is turned off, the first solenoid valve 41 is closed, and the pump is left to stand for a period of time. Then the fourth solenoid valve 44 is opened, and the pressure change in the containment space 110 is detected by the first differential pressure leak detector 53. Simultaneously, the second solenoid valve 42 and / or the third solenoid valve 43 are opened, the second vacuum pump 12 is started, and the pressure value inside the thermal management component 200 is detected by the second pressure sensor 52 installed on the second pipeline 22. When the second pressure sensor 52 detects that the internal pressure of the thermal management component 200 reaches the third preset pressure value, the second solenoid valve 42 is closed. When the second pressure sensor 52 detects that the internal pressure of the thermal management component 200 reaches the second preset pressure value (the second preset pressure value is less than the third preset pressure value), the third solenoid valve 43 is closed, the second vacuum pump 12 is turned off, and the system is left to stand for a period of time. The pressure change inside the thermal management component 200 is detected by the second pressure sensor 52. If the pressure change value inside the thermal management component 200 detected by the second pressure sensor 52 is less than or equal to the preset value, the large leak detection of the thermal management component 200 is passed. The fifth solenoid valve 45 is then opened, and the background helium leak rate in the thermal management component 200 is detected by the helium mass spectrometer leak detector 54. After the detection is completed, the fifth solenoid valve 45 is closed.

[0071] Because the battery housing 100 has a large volume and a long sealing interface, the execution time of step "S400, filling the containment space 110 with helium and detecting the helium leakage rate of the battery housing 100" is relatively long. During the time it takes to fill the containment space 110 with helium and wait, step "S500, performing vacuum accumulation helium detection on the thermal management component 200" can be executed simultaneously to save detection time. Specifically, after the thermal management component 200 is evacuated, the helium in the containment space 110 is used to accumulate the vacuum in the thermal management component 200. After the helium leakage rate of the battery housing 100 is detected, the thermal management component 200 is then subjected to vacuum accumulation helium detection, and the accumulated helium leakage rate is compared with the benchmark specification for determination. Since the thermal management component 200 is evacuated, the amount of gas in the vacuum is minimal, making it insensitive to the temperature of the thermal management component 200 and the ambient temperature. Simultaneously, the helium mass spectrometer leak detector 54 directly detects the helium leakage rate. The detector itself is insensitive to temperature, allowing it to withstand higher product temperatures and ambient temperature fluctuations, thus improving detection accuracy.

[0072] Vacuum accumulation helium detection is a highly sensitive airtightness detection method. It involves creating a vacuum environment to allow helium gas to escape from and accumulate at the leak point of the workpiece under inspection, and then using a helium mass spectrometer to quantitatively analyze the leak rate.

[0073] When testing the helium leakage rate of the battery housing 100, the sixth solenoid valve 46 can be opened, the helium detection gun 55 can be moved, and the helium leakage rate at different locations can be scanned and recorded to compare with the benchmark specifications for judgment.

[0074] According to the airtightness testing method of this application embodiment, the thermal management component 200 is placed in the receiving space 110 of the battery box 100, allowing for simultaneous airtightness testing of the battery box 100 and the thermal management component 200, thereby reducing airtightness testing time and improving the production efficiency of the battery device. Furthermore, helium is filled into the receiving space 110, and helium testing is performed on the battery box 100. Simultaneously, the helium in the receiving space 110 is used to perform vacuum accumulation helium testing on the thermal management component 200, enabling the testing of the airtightness of high-temperature products with high accuracy and precision. Additionally, while performing helium testing on the battery box 100, vacuum accumulation can be performed on the thermal management component 200, reducing testing time and improving the production efficiency of the battery device. The battery box 100 and the thermal management component 200 can share the same helium mass spectrometer leak detector 54. After the helium testing of the battery box 100 is completed, the helium testing of the thermal management component 200 is then performed, reducing testing costs and lowering manufacturing costs.

[0075] According to some embodiments of this application, the helium leakage rate of the battery housing 100 is detected by filling the accommodating space 110 with helium gas, including:

[0076] S410, the containment space 110 is filled with helium multiple times, and the gas in the containment space 110 is extracted between two adjacent filling operations.

[0077] Step "S410, repeatedly fill the containment space 110 with helium and extract the gas from the containment space 110 between two adjacent filling actions" can be regarded as the battery box 100 breathing and replacing itself, and the actions of filling the containment space 110 with helium and extracting the gas from the containment space 110 are repeated in a cycle.

[0078] In some embodiments, such as Figure 2 As shown, the vent 120 of the battery housing 100 is connected to a helium source 81 via a seventh pipe 27. A first pressure regulating valve 61 is installed on the seventh pipe 27, and the first pressure regulating valve 61 is positioned close to the helium source 81. The first pressure regulating valve 61 is initially closed. Opening the first pressure regulating valve 61 allows helium to be introduced into the accommodating space 110.

[0079] In some embodiments, the airtightness testing device further includes a storage tank 71, such as Figure 2As shown, the outlet of the first vacuum pump 11 is connected to the storage tank 71 via an eighth pipe 28. A seventh solenoid valve 47 is installed on the eighth pipe 28, and the seventh solenoid valve 47 is positioned near the outlet of the first vacuum pump 11. The storage tank 71 is connected to the vent 120 of the battery box 100 via a ninth pipe 29. An eighth solenoid valve 48 is installed on the ninth pipe 29, and the eighth solenoid valve 48 is positioned near the storage tank 71. The first vacuum pump 11 and the ninth pipe 29 are connected in parallel. A third pressure sensor 56 is connected to the storage tank 71 to detect the pressure in the storage tank 71. The outlet of the storage tank 71 is connected to a twelfth pipe 32, and a ninth solenoid valve 49 is installed on the twelfth pipe 32, and the ninth solenoid valve 49 is positioned near the storage tank 71.

[0080] When performing step "S410, repeatedly fill the containment space 110 with helium and extract the gas from the containment space 110 between two adjacent filling operations", the first pressure regulating valve 61 is opened to fill the containment space 110 with helium. After the rated flow of helium has been filled, the first pressure regulating valve 61 is closed. Then, the first solenoid valve 41 and the seventh solenoid valve 47 are opened, and the first vacuum pump 11 is started. The rated concentration of helium gas in the containment space 110 of the battery box 100 is drawn into the storage tank 71. When the third pressure sensor 56 detects that the pressure in the storage tank 71 has reached the preset value, the first solenoid valve 41 and the seventh solenoid valve 47 are closed. After standing for a period of time, the eighth solenoid valve 48 is opened, and the high-pressure gas in the storage tank 71 is filled into the containment space 110. After standing for a period of time, the pressure in the storage tank 71 and the containment space 110 is balanced. The eighth solenoid valve 48 is closed, and then the first solenoid valve 41 and the seventh solenoid valve 47 are opened again. The breathing process of the battery box 100 is repeated until the rated number of breaths is reached and then it stops. The breathing of the battery box 100 can accelerate the uniform speed of helium gas in the containment space 110 and shorten the balance time.

[0081] The ninth pipe 29 can prevent the first vacuum pump 11 from being worn due to frequent start-stop cycles, thus improving the service life of the first vacuum pump 11.

[0082] In some embodiments, the vent 120 of the battery housing 100 is connected to the air source 83 through the tenth pipe 30. The tenth pipe 30 is provided with a second pressure regulating valve 62, which is located near the air source 83. The tenth pipe 30 is connected to the seventh pipe 27.

[0083] After the battery housing 100 stops breathing after reaching the rated number of times, the first solenoid valve 41, the seventh solenoid valve 47, and the eighth solenoid valve 48 close, and the containment space 110 contains a uniformly mixed helium gas. A helium gas detector is installed at the vent 120 of the battery housing 100 to detect the helium concentration in the containment space 110, and the pressure in the containment space 110 is detected by the first pressure sensor 51. The first pressure regulating valve 61 and the second pressure regulating valve 62 are opened and adjusted to their rated opening ratios to mix helium and air in a rated ratio. The helium mixture is then introduced into the containment space 110 until the pressure in the containment space 110 reaches the preset pressure value, at which point the first pressure regulating valve 61 and the second pressure regulating valve 62 are closed. Supplementing the containment space 110 with the helium mixture ensures that the pressure in the containment space 110 meets the helium detection requirements.

[0084] In the above scheme, by repeatedly filling the containment space 110 with helium and extracting the gas from the containment space 110 between two adjacent filling operations, the uniform speed of the helium in the containment space 110 can be accelerated, the equilibration time can be shortened, and the detection accuracy can be improved.

[0085] According to some embodiments of this application, before performing vacuum accumulation helium detection on the thermal management component 200, the following is also included:

[0086] S600, the gas in the thermal management unit 200 is extracted multiple times, and nitrogen is introduced into the thermal management unit 200 between two adjacent gas extraction operations.

[0087] In some embodiments, the airtightness testing device further includes a nitrogen source 82. As shown in the figure, the inlet 210 of the thermal management component 200 is connected to the nitrogen source 82 through an eleventh pipe 31. The eleventh pipe 31 is provided with a third pressure regulating valve 63, which is located close to the nitrogen source 82.

[0088] Step "S600, repeatedly extracting gas from the thermal management component 200 and filling the thermal management component 200 with nitrogen between two adjacent gas extraction actions" can be regarded as performing breathing replacement on the thermal management component 200, and cyclically performing the actions of extracting gas from the thermal management component 200 and filling the thermal management component 200 with nitrogen.

[0089] While performing step "S410, repeatedly filling the containment space 110 with helium and extracting the gas from the containment space 110 between two adjacent helium filling actions", step "S600, repeatedly extracting the gas from the thermal management component 200 and filling the thermal management component 200 with nitrogen between two adjacent gas extraction actions" is performed simultaneously; the second solenoid valve 42 and the third solenoid valve 43 are opened, the second vacuum pump 12 is started, the pressure in the thermal management component 200 is pumped to the preset value, and the second solenoid valve 42 and the third solenoid valve 43 are closed; then, the third pressure regulating valve 63 is opened, nitrogen supplied by the nitrogen source 82 is filled into the thermal management component 200, and after the pressure in the thermal management component 200 reaches the preset value, the third pressure regulating valve 63 is closed; then the second solenoid valve 42 and the third solenoid valve 43 are opened again, and the breathing process of the thermal management component 200 is repeated. The breathing process of the thermal management component 200 can cause it to expand and contract, amplify product defects, increase the amount of helium leakage through the defect location into the thermal management component 200, and improve detection accuracy.

[0090] During the breathing replacement process of the thermal management component 200, the second vacuum pump 12 can be connected to the nitrogen source 82, and the nitrogen extracted by the second vacuum pump 12 is delivered to the nitrogen source 82 to realize the recycling of nitrogen.

[0091] In the above scheme, by repeatedly extracting gas from the thermal management component 200 and filling the thermal management component 200 with nitrogen between two adjacent gas extraction actions, the thermal management component 200 is made to breathe. This can amplify the defects of the thermal management component 200, increase the amount of helium leakage that leaks into the thermal management component 200 through the defect location, and improve the detection accuracy.

[0092] According to some embodiments of this application, during the process of filling the containment space 110 with helium and detecting the helium leakage rate of the battery box 100, the gas in the thermal management component 200 is extracted multiple times simultaneously, and nitrogen is injected into the thermal management component 200 between two adjacent gas extraction actions.

[0093] During the execution of step "S400, filling the containment space 110 with helium and detecting the helium leakage rate of the battery box 100", the battery box 100 is subjected to a breathing replacement. Since the breathing replacement time of the battery box 100 is relatively long, step "S600, repeatedly extracting gas from the thermal management component 200 and filling the thermal management component 200 with nitrogen between two adjacent gas extraction actions" can be performed simultaneously. That is, the breathing replacement of the battery box 100 and the breathing replacement of the thermal management component 200 are performed simultaneously.

[0094] In the above scheme, since the helium testing time of the battery box 100 is relatively long, while performing the helium testing of the battery box 100, the thermal management component 200 is subjected to multiple gas extraction and helium filling operations. This allows the airtightness testing of the battery box 100 and the thermal management component 200 to be performed simultaneously during the helium testing waiting time of the battery box 100, thereby shortening the testing time of the battery device and improving the manufacturing efficiency of the battery device.

[0095] In some embodiments, during the static state of the battery housing 100 under air exchange, the pressure in the containment space 110 is detected. If the pressure in the containment space 110 is less than a preset value, it is determined that the thermal management component 200 has a defect, and the gas in the containment space 110 enters the thermal management component 200. Alternatively, it is determined that the battery housing 100 has a defect, and the gas in the containment space 110 leaves the containment space 110 through the defect in the battery housing 100. If the pressure in the containment space 110 is greater than a preset value, it is determined that the thermal management component 200 has a defect, and the gas in the thermal management component 200 enters the containment space 110.

[0096] According to some embodiments of this application, after checking the helium leakage rate of the battery housing 100, a vacuum accumulation helium test is performed on the thermal management component 200.

[0097] After the breathing action of the battery box 100 is completed, when the battery box 100 is tested for helium, the containing space 110 contains helium. At this time, the containing space 110 is under positive pressure. Simultaneously, the thermal management component 200 is breathed and replaced, and the thermal management component 200 accumulates vacuum. The airtightness test of the battery box 100 and the airtightness test of the thermal management component 200 are carried out simultaneously. After the helium test of the battery box 100 is completed, the helium test of the thermal management component 200 is carried out, shortening the test time.

[0098] In the above scheme, while performing helium gas testing on the battery box 100, the thermal management component 200 located in the housing space 110 is vacuum-accumulated helium gas tested using helium gas in the housing space 110, which can shorten the airtightness testing time and improve the testing efficiency.

[0099] According to some embodiments of this application, after performing a vacuum accumulation helium test on the thermal management component 200, the helium gas in the containment space 110 is extracted and the containment space 110 is restored to atmospheric pressure; nitrogen gas is introduced into the thermal management component 200 and the internal pressure of the thermal management component 200 is restored to atmospheric pressure.

[0100] After completing the airtightness test of the battery housing 100 and the airtightness test of the thermal management component 200, the helium gas in the containment space 110 is extracted. The helium gas can be stored in the storage tank 71 or transported to the helium recovery device via the storage tank 71 to restore the containment space 110 to atmospheric pressure. At the same time, nitrogen gas is introduced into the thermal management component 200 to restore the internal pressure of the thermal management component 200 to atmospheric pressure. The inlet 210 and outlet 220 of the thermal management component 200 are then sealed to protect the thermal management component 200 with nitrogen gas.

[0101] In the above scheme, the helium in the containment space 110 is extracted to realize the recycling of helium and reduce the pollution of helium to the environment; nitrogen is filled into the thermal management component 200 and the internal pressure of the thermal management component 200 is restored to atmospheric pressure. Nitrogen can reduce the oxidation and corrosion of the detection component by impurities such as oxygen and moisture.

[0102] According to some embodiments of this application, the negative pressure is drawn into the accommodating space 110, and the pressure change within the accommodating space 110 is detected, including:

[0103] S210, the pressure in the containment space 110 is reduced to a first preset pressure value, the pumping is stopped, and the space is left to stand for a first preset time. The pressure change in the containment space 110 is detected. If the pressure change in the containment space 110 is greater than the preset value, the detection is stopped. If the pressure change in the containment space 110 is less than or equal to the preset value, helium is introduced into the containment space 110, and the helium leakage rate of the battery box 100 is detected.

[0104] When the containment space 110 is under negative pressure, by detecting the pressure change of the containment space 110 within a first preset time, it is possible to determine whether there is a defect in the battery box 100, so as to stop the detection or continue the subsequent detection steps.

[0105] In the above scheme, the pressure in the containment space 110 is pumped down to a first preset pressure value, the pumping is stopped, and the space is left to stand for a first preset time. The subsequent actions are determined based on the detected pressure change in the containment space 110. If the pressure change value in the containment space 110 is greater than the preset value, it indicates that the battery box 100 has a defect, and the detection is stopped, and the battery box 100 is judged as an unqualified product. If the pressure change value in the containment space 110 is less than or equal to the preset value, it indicates that the battery box 100 is qualified, helium is filled into the containment space 110, and micro-leakage detection is performed on the battery box 100.

[0106] According to some embodiments of this application, evacuating the thermal management component 200 and performing helium background detection on the thermal management component 200 includes:

[0107] S310, the pressure inside the thermal management component 200 is evacuated to the second preset pressure value, the evacuation is stopped, and the unit is left to stand for the second preset time. A helium background test is performed on the thermal management component 200. If the helium background leakage rate is greater than the preset value, the test is stopped. If the helium background leakage rate is less than or equal to the preset value, helium is filled into the containment space 110, and the helium leakage rate value of the battery box 100 is detected. At the same time, a vacuum accumulation helium test is performed on the thermal management component 200.

[0108] With the thermal management component 200 in a vacuum state, the pressure change inside the thermal management component 200 is detected by the second pressure sensor 52 within a second preset time period. This allows the determination of whether the thermal management component 200 has a defect, i.e., a large leak test is performed on the thermal management component 200. If the pressure change value inside the thermal management component 200 is greater than the preset value, the thermal management component 200 has a defect, and the test is stopped. If the pressure change value inside the thermal management component 200 is less than or equal to the preset value, the large leak test of the thermal management component 200 is passed, and a helium background test is performed: the second solenoid valve 42, the third solenoid valve 43 and the second vacuum pump 12 are closed, the fifth solenoid valve 45 is opened, and the helium mass spectrometer leak detector 54 is used to perform a helium background test on the thermal management component 200.

[0109] In the above scheme, the pressure inside the thermal management component 200 is evacuated to a second preset pressure value, the evacuation is stopped, and the system is left to stand for a second preset time. The background helium leakage rate of the thermal management component 200 is then detected to improve the accuracy of the vacuum cumulative helium test of the thermal management component 200. Based on the background helium leakage rate of the thermal management component 200, if the helium leakage rate is less than or equal to a preset value, the product is considered qualified, and the process of filling the containment space 110 with helium continues, while the helium leakage rate of the battery box 100 is detected, and the vacuum cumulative helium test of the thermal management component 200 is performed. If the helium leakage rate is greater than the preset value, the thermal management component 200 is defective, the product is considered unqualified, and the testing is stopped.

[0110] Please refer to Figure 2 and further refer to Figures 3 to 9 The airtightness testing method of this application will be further described below. Figure 3 This is a schematic diagram illustrating the negative pressure and vacuum stages provided in some embodiments of this application. Figure 4 This diagram illustrates the large leak detection and background detection stages provided in some embodiments of this application. Figure 5 This is a schematic diagram illustrating the helium filling stage provided in some embodiments of this application. Figure 6 This is a schematic diagram of the respiratory replacement stage provided in some embodiments of this application. Figure 7 The diagram illustrates the detection phase provided in some embodiments of this application. Figure 8 This is a schematic diagram of the battery casing testing process provided in some embodiments of this application. Figure 9This is a schematic diagram of the testing process for thermal management components provided in some embodiments of this application, along with 8 and Figure 9 In this context, "OK" indicates that the test has passed, and "NG" indicates that the test has failed. This application provides a method for testing airtightness, comprising:

[0111] During the negative pressure and vacuuming phase: First solenoid valve 41, seventh solenoid valve 47, and ninth solenoid valve 49 are opened, and first vacuum pump 11 is started to draw negative pressure into the containment space 110. The pressure sensor 51 detects that the pressure in the containment space 110 has reached the first preset pressure value and stops, then closes first vacuum pump 11, first solenoid valve 41, seventh solenoid valve 47, and ninth solenoid valve 49. Simultaneously, second solenoid valve 42 and third solenoid valve 43 are opened, and second vacuum pump 12 is started to evacuate the thermal management component 200. When second pressure sensor 52 detects that the pressure in the thermal management component 200 has reached the third preset pressure value, second solenoid valve 42 is closed. When second pressure sensor 52 detects that the pressure in the thermal management component 200 has reached the second preset pressure value (the second preset pressure value is less than the third preset pressure value), second vacuum pump 12 and third solenoid valve 43 are closed.

[0112] Large leak detection and background test phases: After a period of settling, open the fourth solenoid valve 44 and use the first differential pressure leak detector 53 to detect pressure changes in the containment space 110. If the pressure change in the containment space 110 is greater than a preset value, stop the test and close the fourth solenoid valve 44. If the pressure change in the containment space 110 is less than or equal to the preset value, the large leak detection of the battery box 100 is passed, and the fourth solenoid valve 44 is closed. Simultaneously, use the second pressure sensor 52 to detect pressure changes inside the thermal management component 200. If the internal pressure change in the thermal management component 200 is greater than a preset value, the thermal management component 200 has a defect, and the test is stopped. If the internal pressure change in the thermal management component 200 is less than or equal to the preset value, the large leak detection of the thermal management component 200 is passed, and helium background testing is performed. Open the fifth solenoid valve 45 and use the helium mass spectrometer leak detector 54 to perform helium background detection on the thermal management component 200. If the helium background leak rate is greater than the preset value, stop the detection and close the fifth solenoid valve 45; if the helium background leak rate is less than or equal to the preset value, close the fifth solenoid valve 45 and wait for subsequent steps.

[0113] Helium charging stage: Open the first pressure regulating valve 61, and helium supplied by the helium source 81 fills the containing space 110. After the rated flow of helium is filled, close the first pressure regulating valve 61. At the same time, open the third pressure regulating valve 63, and nitrogen supplied by the nitrogen source 82 fills the thermal management component 200. After the rated pressure of nitrogen is filled, close the third pressure regulating valve 63.

[0114] Respiration replacement phase: Open the first solenoid valve 41 and the seventh solenoid valve 47, start the first vacuum pump 11, and the rated concentration of helium gas in the containment space 110 of the battery box 100 is drawn into the storage tank 71. When the third pressure sensor 56 detects that the pressure in the storage tank 71 has reached the preset value, the first solenoid valve 41 and the seventh solenoid valve 47 are closed. After standing for a period of time, open the eighth solenoid valve 48, and the high-pressure gas in the storage tank 71 is filled into the containment space 110. After standing for a period of time, the pressure in the storage tank 71 and the containment space 110 is balanced, the eighth solenoid valve 48 is closed, and then the first solenoid valve is opened. 41 and the seventh solenoid valve 47 repeat the breathing process of the battery box 100 until the breathing reaches the rated number and stops. The breathing of the battery box 100 can accelerate the uniform speed of helium in the containment space 110 and shorten the balancing time. Then, the first pressure regulating valve 61 and the second pressure regulating valve 62 are opened and adjusted to the rated opening degree so that helium and air are mixed in the rated ratio. The helium mixture is filled into the containment space 110 until the pressure in the containment space 110 reaches the preset pressure value and stops. Then the first pressure regulating valve 61 and the second pressure regulating valve 62 are closed. Simultaneously, the second solenoid valve 42 and the third solenoid valve 43 are opened, the second vacuum pump 12 is started, and the pressure in the thermal management component 200 is drawn to the preset value. Then, the second solenoid valve 42 and the third solenoid valve 43 are closed. Then, the third pressure regulating valve 63 is opened, and nitrogen supplied by the nitrogen source 82 is introduced into the thermal management component 200. After the pressure in the thermal management component 200 reaches the preset value, the third pressure regulating valve 63 is closed. Then, the second solenoid valve 42 and the third solenoid valve 43 are opened again, and the breathing process of the thermal management component 200 is repeated.

[0115] Testing Phase: The sixth solenoid valve 46 is opened, and the robotic arm 91 drives the helium detection gun 55 to scan and detect along the sealed interface of the battery housing 100. The helium leakage rate at different locations is recorded and compared with the benchmark specifications for judgment. The sixth solenoid valve 46 is then closed. While the battery housing 100 is being helium tested, the thermal management component 200 continuously performs a breathing action until a fixed time is reached. After this breathing action stops, the thermal management component 200 is evacuated and allowed to accumulate helium. Once the helium test of the battery housing 100 is complete, the fifth solenoid valve 45 is opened, and the thermal management component 200 begins vacuum accumulation helium testing. The accumulated helium leakage rate is compared with the benchmark specifications for judgment. The simultaneous evacuation and accumulation of helium in the thermal management component 200 and the battery housing 100 during the scanning helium test of the battery housing 100 allows for simultaneous testing of both components, saving significant testing time. Furthermore, a single helium mass spectrometer can be used to test both chambers, reducing costs.

[0116] Finally, the helium gas in the housing space 110 of the battery box 100 is extracted, and the pressure in the housing space 110 is restored to atmospheric pressure; nitrogen gas is introduced into the thermal management component 200, and the pressure in the thermal management component 200 is restored to atmospheric pressure.

[0117] Secondly, this application also provides a controller, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the airtightness detection method provided in the above embodiments.

[0118] Memory and processor can be connected via a bus or other means.

[0119] Thirdly, this application also provides an airtightness detection system, which includes the controller provided in the above embodiments.

[0120] The airtightness testing system also includes the aforementioned valves, vacuum pumps, pressure sensors, a first differential pressure leak detector 53, a helium mass spectrometer leak detector 54, a helium detection gun 55, a storage tank 71, a helium gas source 81, a nitrogen gas source 82, and an air gas source 83. The controller is electrically connected to the various valves, vacuum pumps, pressure sensors, the first differential pressure leak detector 53, the helium mass spectrometer leak detector 54, the helium detection gun 55, the storage tank 71, the helium gas source 81, the nitrogen gas source 82, and the air gas source 83 to facilitate the execution of the aforementioned airtightness testing method.

[0121] Fourthly, this application also provides a computer-readable storage medium storing computer-executable instructions for performing the airtightness detection method provided in the above embodiments.

[0122] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically include computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium. It should be noted that computer-readable storage media may be non-volatile or volatile.

[0123] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for detecting airtightness, characterized in that, include: The thermal management components are placed within the housing space of the battery box; A negative pressure is drawn into the containment space, and the pressure change within the containment space is detected. The thermal management component is evacuated, and a helium background test is performed on the thermal management component. Helium gas was filled into the containment space, and the helium leakage rate of the battery box was detected. The thermal management component was subjected to vacuum accumulation helium testing. During the process of filling the containment space with helium and detecting the helium leakage rate of the battery box, the gas in the thermal management component is extracted multiple times simultaneously, and nitrogen is injected into the thermal management component between two adjacent gas extraction actions. After checking the helium leakage rate of the battery housing, a vacuum accumulation helium test is performed on the thermal management component.

2. The airtightness testing method according to claim 1, characterized in that, The process of filling the containment space with helium and detecting the helium leakage rate of the battery housing includes: The containment space is filled with helium multiple times, and the gas in the containment space is extracted between two adjacent filling operations.

3. The airtightness testing method according to claim 1, characterized in that, After performing a vacuum accumulation helium test on the thermal management component, the helium gas in the containment space is extracted and the containment space is restored to atmospheric pressure; nitrogen gas is then introduced into the thermal management component and the internal pressure of the thermal management component is restored to atmospheric pressure.

4. The airtightness testing method according to claim 1, characterized in that, The step of drawing negative pressure into the containment space and detecting pressure changes within the containment space includes: The pressure in the containment space is reduced to a first preset pressure value. The pumping is stopped, and the space is left to stand for a first preset time. The pressure change in the containment space is detected. If the pressure change in the containment space is greater than the preset value, the detection is stopped. If the pressure change in the containment space is less than or equal to the preset value, helium is introduced into the containment space, and the helium leakage rate of the battery box is detected.

5. The airtightness testing method according to claim 1, characterized in that, The step of evacuating the thermal management component and performing helium background detection on the thermal management component includes: The pressure inside the thermal management component is evacuated to a second preset pressure value, the evacuation is stopped, and the component is left to stand for a second preset time. A helium background test is performed on the thermal management component. If the helium background leakage rate is greater than a preset value, the test is stopped. If the helium background leakage rate is less than or equal to the preset value, helium is filled into the containment space, and while the helium leakage rate of the battery box is being tested, a vacuum accumulation helium test is performed on the thermal management component.

6. A controller, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the airtightness detection method according to any one of claims 1-5.

7. An airtightness detection system, characterized in that, Includes the controller as described in claim 6.

8. A computer-readable storage medium storing computer-executable instructions, characterized in that, The computer-executable instructions are used to execute the airtightness detection method according to any one of claims 1-5.

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