Sealing nail structure, battery monomer and helium detection method thereof

Abstract

The invention relates to a sealing nail structure, a battery cell and a helium detection method thereof. The sealing nail structure is applied to a liquid injection hole of a battery monomer, and comprises a first sealing nail which can be embedded in a liquid injection through hole; the second sealing nail comprises a main body part and a deformation part; the main body part can be sealed in the liquid injection groove and comprises a first surface facing the first sealing nail and a second surface opposite to the first sealing nail; the deformation part is arranged on the first surface and the second surface; when pressure is applied to the first surface, the deformation part deforms, so that the second surface can push the first sealing nail to be integrally embedded into and sealed in the liquid injection through hole. When the first sealing nail partially enters the liquid injection through hole, the sealing nail structure can effectively identify the problems of poor welding and the like at the welding joint of the second sealing nail, so that the accuracy of a helium detection result is guaranteed, and the sealing reliability of the battery is further improved; meanwhile, the sealing nail structure can achieve double-layer sealing, and the risk of electrolyte leakage is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and in particular, to a sealing nail structure, a battery cell, and a helium leak detection method therefor. Background Art

[0002] As the current mainstream energy storage device, lithium-ion batteries are widely used in portable electronic devices, electric vehicles, and energy storage systems. To ensure the sealing of the electrolyte inside the battery and the reliability of the overall structure, the battery housing is usually provided with a liquid injection hole for the injection and subsequent sealing of the electrolyte. The liquid injection hole generally includes a liquid injection groove provided on the housing and a liquid injection through hole at the bottom thereof. After the liquid injection process is completed, the entire liquid injection hole needs to be sealed by a sealing nail.

[0003] The sealing nail structure generally includes a sealing glue nail and a sealing aluminum nail. The sealing glue nail is used to block the liquid injection through hole, and the sealing aluminum nail is arranged in the liquid injection groove and the overall sealing is completed by welding. To ensure the airtightness of the battery, a helium leak detection (helium leak detection) process needs to be carried out after sealing. This process injects a certain amount of helium into the battery and detects whether helium leaks outside the battery to judge the welding and sealing performance.

[0004] In the traditional technology, the welding and helium leak detection process of the battery sealing nail includes: partially pressing the sealing glue nail into the liquid injection through hole (half-inserted glue nail), then injecting helium into the battery (helium filling), then completely pressing the sealing glue nail into the liquid injection through hole (fully inserted glue nail), then placing the sealing aluminum nail and performing pre-welding and welding, and finally performing helium leak detection operation. This method evaluates the quality of the sealed weld by detecting whether there is helium leakage in the sealed weld area.

[0005] However, in the above traditional process flow, since the sealing glue nail has been completely pressed into the liquid injection through hole before helium leak detection, the entire liquid injection hole is in a closed state during helium leak detection, resulting in the inability of helium leak detection to effectively identify the problem of poor welding at the welded joint of the sealing aluminum nail, causing the helium leak detection to fail, and further affecting the reliable evaluation of the battery sealing quality. Summary of the Invention

[0006] Based on this, it is necessary to provide a sealing nail structure, a battery cell, and a helium leak detection method therefor that can effectively identify the problem of poor welding at the welded joint of the sealing aluminum nail, ensure the accuracy of the helium leak detection result, and further improve the reliability of the battery sealing quality evaluation for the above technical problems.

[0007] In a first aspect, the present application provides a sealing nail structure applied to a liquid injection hole of a battery cell. The liquid injection hole includes a liquid injection groove and a liquid injection through hole opened on the liquid injection groove. The sealing nail structure includes:

[0008] A first sealing nail capable of being embedded in the liquid injection through hole;

[0009] The second sealing nail includes a main body portion and a deformation portion; the main body portion can be sealed in the liquid injection groove, and the main body portion includes a first surface facing the first sealing nail and a second surface facing away from the first sealing nail; the deformation portion is disposed on the first surface and the second surface;

[0010] Wherein, when pressure is applied to the first surface, the deformation portion can deform, so that the second surface can push the first sealing nail to integrally embed and seal in the liquid injection through hole.

[0011] In one embodiment, the first sealing nail includes a sealing portion and a guiding portion, and the guiding portion is fixedly connected to the sealing portion; the guiding portion is disposed in the liquid injection through hole, and under the action of pressure, the second surface can push the sealing portion into the liquid injection through hole, so that the sealing portion embeds and seals in the liquid injection through hole.

[0012] In one embodiment, the diameter of the sealing portion is larger than the aperture of the liquid injection through hole to be able to seal the liquid injection through hole.

[0013] In one embodiment, a recessed portion is provided on the guiding portion along its axial direction; wherein, when the sealing portion does not enter the liquid injection through hole, a flow channel for gas or liquid is formed by the recessed portion, the second surface, the inner wall of the liquid injection through hole, and the inner wall of the liquid injection groove.

[0014] In one embodiment, the deformation portion of the second sealing nail is a groove structure disposed on the first surface and the second surface.

[0015] In one embodiment, the recessed portion is a groove-shaped or spiral-shaped structure formed by the guiding portion extending along its own axial direction.

[0016] In one embodiment, the projection of the deformation portion along the direction perpendicular to the first surface or the second surface falls on the liquid injection groove.

[0017] In a second aspect, the present application further provides a battery cell, including any one of the sealing nail structures provided in the first aspect. The battery cell further includes a liquid injection hole, and the liquid injection hole includes a liquid injection through hole and a liquid injection groove; the liquid injection through hole is opened at the bottom of the liquid injection groove and penetrates into the interior of the battery cell.

[0018] In a third aspect, the present application further provides a helium leak detection method, which is applied to the sealing nail structure provided in the first aspect. The method includes:

[0019] Controlling the first sealing nail to partially enter the liquid injection through hole so that the liquid injection through hole is available for the inspection gas to pass through;

[0020] Injecting helium gas into the interior of the battery cell;

[0021] Welding the second sealing nail to the liquid injection groove to obtain a welded connection portion;

[0022] Perform helium leak detection on the welded connection part.

[0023] In one embodiment, the method further includes:

[0024] When the detection value of the welded connection part is lower than or equal to the preset threshold, apply pressure to the main body of the second sealing nail to push the first sealing nail into and seal the liquid injection through hole;

[0025] When the detection value of the welded connection part is higher than the preset threshold, adjust the welded connection part and perform helium leak detection again after adjustment.

[0026] The above-mentioned sealing nail structure, battery cell and its helium leak detection method, the sealing nail structure is applied to the liquid injection hole of the battery cell. The liquid injection hole includes a liquid injection groove and a liquid injection through hole opened on the liquid injection groove. The sealing nail structure includes: a first sealing nail that can be embedded in the liquid injection through hole; a second sealing nail that includes a main body part and a deformation part; the main body part can seal the liquid injection groove, the main body part includes a first surface facing the first sealing nail and a second surface facing away from the first sealing nail; the deformation part is arranged on the first surface and the second surface; wherein, when pressure is applied to the first surface, the deformation part can generate deformation so that the second surface can push the first sealing nail as a whole into and seal the liquid injection through hole. The first sealing nail and the second sealing nail of this sealing nail structure can achieve double-layer sealing, reducing the risk of electrolyte leakage; at the same time, when the first sealing nail partially enters the liquid injection through hole, this sealing nail structure can effectively identify problems such as poor welding at the welded connection of the second sealing nail, ensuring the accuracy of the helium leak detection result, and thus improving the reliability of the battery sealing quality assessment. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0028] Figure 1 It is a schematic structural diagram of the first sealing nail in one embodiment;

[0029] Figure 2 It is a schematic structural diagram of the second sealing nail in one embodiment;

[0030] Figure 3 It is a schematic diagram when the first sealing nail partially enters the liquid injection through hole in one embodiment;

[0031] Figure 4 It is a schematic diagram when the first sealing nail is completely fitted into the liquid injection through hole in one embodiment;

[0032] Figure 5 Schematic diagram of the top cover structure of a battery cell in an embodiment;

[0033] Figure 6 Schematic flow chart of a helium leak detection method in an embodiment.

[0034] 10. Liquid injection through hole; 20. Liquid injection groove; 100. First sealing nail; 200. Second sealing nail; 102. Sealing part; 104. Introduction part; 106. Concave part; 202. Main body part; 204. Deformation part. Detailed implementation manners

[0035] To make the above objects, features, and advantages of the present application more obvious and understandable, the following will describe the detailed implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0036] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present application.

[0037] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0038] In this application, unless otherwise clearly specified or limited, terms such as "installed", "connected", "linked", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] In this application, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0040] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it may be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation manners.

[0041] In order to solve the problem that in the related art, the poor welding at the welded joint of the sealed aluminum nail cannot be effectively identified, resulting in the failure of helium leak detection, in a first aspect, please refer to Figure 1 and Figure 2 , an embodiment of this application provides a sealing nail structure. This sealing nail structure is applied to the liquid injection hole of a battery cell. The liquid injection hole includes a liquid injection groove 20 and a liquid injection through hole 10 opened on the liquid injection groove 20. This sealing nail structure includes a first sealing nail 100 and a second sealing nail 200. Figure 1 Fig. shows a schematic structural diagram of the first sealing nail 100 in an embodiment of this application. Figure 2The structural schematic diagram of the second sealing nail 200 in an embodiment of the present application is shown. The first sealing nail 100 can be embedded in the liquid injection through hole 10; the second sealing nail 200 includes a main body portion 202 and a deformation portion 204; the main body portion 202 can seal the liquid injection groove 20, and the main body portion 202 includes a first surface facing the first sealing nail 100 and a second surface facing away from the first sealing nail 100; the deformation portion 204 is arranged on the first surface and the second surface; wherein, when pressure is applied to the first surface, the deformation portion 204 can generate deformation, so that the second surface can push the first sealing nail 100 to be integrally embedded and sealed in the liquid injection through hole 10.

[0042] Wherein, the first sealing nail 100 is a sealing glue nail, and the second sealing nail 200 is a sealing aluminum nail.

[0043] The first sealing nail 100 includes a sealing portion 102 and a guiding portion 104, and the guiding portion 104 is fixedly connected to the sealing portion 102; the guiding portion 104 is arranged in the liquid injection through hole 10, and under the action of pressure, the second surface can push the sealing portion 102 into the liquid injection through hole 10, so that the sealing portion 102 is embedded and sealed in the liquid injection through hole 10. Wherein, a recessed portion 106 is arranged on the guiding portion 104 along its axial direction; when a part of the guiding portion 104 enters the liquid injection through hole 10, helium gas can escape through the recessed portion 106.

[0044] The second sealing nail 200 includes a main body portion 202 and a deformation portion 204; the main body portion 202 is arranged inside the liquid injection groove 20 and abuts against the sealing portion 102; the deformation portion 204 is arranged on the first surface and the second surface of the main body portion 202, and when pressure is applied to the first surface, the deformation portion 204 generates deformation, so that the second surface can push the first sealing nail 100 to be integrally embedded and sealed in the liquid injection through hole 10.

[0045] The sealing nail structure is applied to the liquid injection hole of the battery cell to effectively seal the liquid injection hole of the battery cell, ensure that the electrolyte will not leak after injection, and at the same time ensure the airtightness and electrochemical stability of the battery cell during subsequent use. The first sealing nail 100 is used to initially block the liquid injection through hole 10. Specifically, during the use of the sealing nail structure, the first sealing nail 100 is not completely embedded in the liquid injection through hole 10 at one time, but first ensures that a part of the guiding portion 104 enters the inside of the liquid injection through hole 10, such as Figure 3The figure shows a schematic diagram of the import part 104 partially entering the interior of the liquid injection through-hole 10. At this time, detection gases such as helium can escape through the recessed part 106, so as to effectively perform helium leak detection on the welding area of the second sealing nail 200. Optionally, after the welding area of the second sealing nail 200 passes the helium leak detection, pressure is applied to the first surface of the main body part 202, and the deformation part 204 can generate deformation, so that the second surface can push the first sealing nail 100 as a whole to be embedded and sealed in the liquid injection through-hole 10, realizing the final sealing of the liquid injection through-hole 10 by the first seal, and preventing the leakage of the electrolyte of the battery cell, such as Figure 4 The figure shows a schematic diagram of the first sealing nail 100 being completely fitted into the liquid injection through-hole 10. Among them, after the second sealing nail 200 is arranged in the liquid injection groove 20, the second sealing nail 200 and the liquid injection groove 20 are welded to obtain the welding area of the second sealing nail 200.

[0046] In this embodiment, in the helium leak detection stage, the first sealing nail 100 has not completely sealed the liquid injection through-hole 10, so that the helium injected into the battery cell can escape through the recessed part 106 axially arranged on the import part 104, so as to realize the leak detection of the second sealing nail 200 (that is, the welding area of the second sealing nail 200), which can avoid the situation in the traditional technology that helium cannot escape due to the sealing glue nail (that is, the first seal) completely blocking the liquid injection through-hole 10 in advance, effectively identify the welding defect problem at the welding joint of the sealing aluminum nail, ensure the accuracy of the helium leak detection result, and further improve the reliability of the battery sealing quality assessment. After the helium leak detection is completed, when pressure is applied to the first surface of the main body part 202, the deformation part 204 can generate deformation, so that the second surface of the main body part 202 can push the first sealing nail 100 as a whole to be embedded and sealed in the liquid injection through-hole 10, realizing the final sealing of the liquid injection through-hole 10 by the first sealing nail 100, which can enhance the sealing tightness between the first sealing nail 100 and the liquid injection through-hole 10; it can also avoid multiple assemblies or re-operations, and improve the efficiency of the liquid injection hole sealing process.

[0047] In an exemplary embodiment, a recessed part 106 is axially arranged on the import part 104; among them, when the sealing part 102 does not enter the liquid injection through-hole 10, the recessed part 106, the second surface, the inner wall of the liquid injection through-hole 10 and the inner wall of the liquid injection groove 20 form a gas or liquid flow channel.

[0048] Exemplarily, when a part of the introduction portion 104 of the first sealing nail 100 enters the liquid injection through-hole 10, since the introduction portion 104 is provided with a recess 106 along its axial direction, the introduction portion 104 does not completely fit with the inner wall of the liquid injection through-hole 10. Instead, a limited gap region is formed between the recess 106 and the inner wall of the liquid injection through-hole 10. One end of this gap region communicates with the internal space of the battery cell, and the other end extends to the liquid injection groove 20 located outside the liquid injection through-hole 10, so that the recess 106, the second surface, the inner wall of the liquid injection through-hole 10, and the inner wall of the liquid injection groove 20 form a gas or liquid flow channel. Helium can escape from the internal space of the battery cell through the recess 106 to this flow channel. When there is a problem with the soldering joint of the second sealing nail 200, helium can escape from the soldering joint of the second sealing nail 200, and thus the helium leak detection result shows that the helium leak detection is unqualified.

[0049] In this embodiment, this flow channel communicates with the soldering joint of the second sealing nail 200, forming a stable and preset leak detection channel in structure. During the helium leak detection process, the escaped helium can converge in this flow channel and can be quickly sensed by an external detection instrument when there is a problem with the soldering joint of the second sealing nail 200, improving the accuracy and response speed of the helium leak detection process.

[0050] In an exemplary embodiment, the diameter of the sealing portion 102 is larger than the aperture of the liquid injection through-hole 10 to be able to seal the liquid injection through-hole 10.

[0051] Optionally, the diameter of the sealing portion 102 is larger than the aperture of the liquid injection through-hole 10, which can ensure that when pressure is applied to the sealing portion 102, the sealing portion 102 can be pressed tightly in the radial direction, so as to be firmly fitted inside the liquid injection through-hole 10, making a reliable airtight connection formed between the outer wall of the sealing portion 102 and the inner wall of the liquid injection through-hole 10. Through this airtight connection, the opening of the liquid injection through-hole 10 is effectively closed, thereby blocking the entry of external gas or liquid, and at the same time preventing the leakage of the electrolyte inside the battery cell.

[0052] In this embodiment, the diameter of the sealing portion 102 is larger than the aperture of the liquid injection through-hole 10, so that the sealing portion 102 can be completely fitted inside the liquid injection through-hole 10, thus forming a tight contact, greatly reducing the risk of air leakage, effectively preventing electrolyte leakage or external gas entry, and significantly improving the sealing reliability and use safety of the battery cell. At the same time, by achieving sealing through size matching and pressure, it does not rely on auxiliary materials such as sealant and sealing ring, which can reduce the process complexity and improve the overall assembly efficiency and consistency.

[0053] In an exemplary embodiment, the recess 106 is a groove-shaped or spiral-shaped structure formed by the introduction portion 104 extending along its own axial direction.

[0054] Optionally, the recess 106 is configured to extend along the axial direction of the introduction portion 104 itself, and specifically, a groove-shaped or spiral configuration can be adopted. When a part of the introduction portion 104 of the first sealing nail 100 enters the liquid injection through hole 10, a gap region is formed between the outer peripheral surface of the introduction portion 104 and the inner wall of the liquid injection through hole 10. Among them, the groove-shaped structure is a straight groove extending along the length direction on the surface of the introduction portion 104; while the spiral structure is a spiral groove, similar to a thread but without the function of screwing in.

[0055] In an exemplary embodiment, the diameter of the main body portion 202 is larger than the aperture of the sealing portion 102.

[0056] Exemplarily, the main body portion 202 of the second sealing nail 200 (sealing aluminum nail) is disposed in the liquid injection groove 20 of the liquid injection hole, while the sealing portion 102 of the first sealing nail 100 (sealing glue nail) is located in the liquid injection through hole 10. The diameter of the main body portion 202 is larger than the outer diameter of the sealing portion 102, so that the sealing aluminum nail can completely cover the upper surface of the sealing glue nail in terms of size and provide a sufficient contact area for applying an axial pressing force subsequently, thereby effectively pushing the sealing glue nail to be fully fitted into the liquid injection through hole 10 to achieve reliable sealing.

[0057] In an exemplary embodiment, the deformation portion 204 of the second sealing nail 200 is a groove structure provided on the first surface and the second surface.

[0058] Exemplarily, please refer to again Figure 2 that the deformation portion 204 is a groove structure, which can provide sufficient deformation ability when an external pressure is applied to the second sealing nail 200, and thus play a role in the pressing process of the first sealing nail 100. The groove structure helps to enhance the elasticity and deformation ability of the second sealing nail 200, so that when pressure is applied, the deformation portion 204 can generate a certain axial deformation or expansion, so as to better push the first sealing nail 100 to completely enter the liquid injection through hole 10, and make the sealing portion 102 embed and seal in the liquid injection through hole 10.

[0059] In a preferred embodiment when the first sealing nail 100 is a glue nail, the projection of the deformation portion 204 in the direction perpendicular to the first surface or the second surface falls on the liquid injection groove 20.

[0060] Optionally, the projection of the deformation portion 204 of the second sealing nail 200 in the direction perpendicular to the first surface or the second surface of the main body portion 202 preferably falls on the liquid injection groove 20, that is, the deformation in the vertical direction of the deformation portion 204 is mainly concentrated in the area corresponding to the liquid injection groove 20, which can ensure that when pressure is applied to the main body portion 202, the deformation force can be more directly and effectively transmitted to the first sealing nail 100 to enhance the sealing effect.

[0061] In a second aspect, the present application provides a battery cell, as Figure 5 shown in the schematic diagram of the top cover structure of the battery cell; the battery cell includes any one of the sealing nail structures provided in the first aspect, and the battery cell further includes a liquid injection hole, and the liquid injection hole includes a liquid injection groove 20 and a liquid injection through hole 10.

[0062] Among them, the liquid injection through hole 10 is opened at the bottom of the liquid injection groove 20 and penetrates into the interior of the battery cell.

[0063] The sealing nail structure provided in the first aspect, such as the combination of a sealing rubber nail and a sealing aluminum nail, forms an airtight seal at the liquid injection hole through precise matching and pressing force, thereby preventing electrolyte leakage or air entry. Especially during the helium leak detection process, through the improved structural design, the welding quality and the integrity of the seal can be ensured, and the safety and stability of the battery can be improved.

[0064] In this embodiment, by optimizing the structural design of the sealing nail and combining the helium leak detection method, the sealing performance of the battery cell and the accuracy of the welding detection are significantly improved, ensuring the safety and reliability of the battery. Especially during the manufacturing process, potential welding defects can be effectively eliminated, thereby avoiding the risk of failure during subsequent use.

[0065] In a third aspect, as Figure 6 shown, the present application provides a helium leak detection method applied to the sealing nail structure of the first aspect; the method includes step 602 to step 606. Among them:

[0066] Step 602, controlling the first sealing nail 100 to partially enter the liquid injection through hole 10 so that the liquid injection through hole 10 is available for the inspection gas to pass through.

[0067] Step 604, injecting helium gas into the interior of the battery cell.

[0068] Step 606, welding the second sealing nail 200 to the liquid injection groove 20 to obtain a welded connection portion.

[0069] Step 608, performing helium leak detection on the welded connection portion.

[0070] Among them, the first sealing nail 100 is a sealing rubber nail, and the second sealing nail 200 is a sealing aluminum nail.

[0071] Exemplarily, electrolyte is injected into the interior of the battery cell through the liquid injection hole, and after injecting the electrolyte, the sealing rubber nail (the first sealing nail 100) is placed at the liquid injection through hole 10 of the liquid injection hole, and the sealing rubber nail is pressed so that the sealing rubber nail is partially located in the liquid injection through hole 10 of the liquid injection hole; at this time, the sealing rubber nail does not seal the liquid injection through hole 10, so that the gas in the battery cell can be pumped out during the subsequent denting process, and helium gas can be injected into the battery cell during the subsequent helium injection process.

[0072] The concave forming process includes extracting the gas inside the battery cell to create a negative pressure environment inside the battery cell. The concave forming process can extract the gas between the layers of the stacked body inside the battery cell or between the stacked body and the housing, so that the housing and the stacked body are closely attached to each other, avoiding the formation of wrinkles and lithium plating caused by the free expansion of the electrode sheet during the subsequent formation process. After the concave forming process, a small amount of helium gas is injected into the battery cell through the liquid injection hole to provide a helium gas source for the subsequent helium leak detection process.

[0073] The sealing aluminum nail (the second sealing nail 200) is disposed in the liquid injection groove 20. At this time, the sealing glue nail is still partially in the liquid injection through hole 10, and helium gas can escape from the recessed portion 106 of the sealing glue nail. After the sealing aluminum nail is disposed in the liquid injection groove 20, the sealing aluminum nail and the liquid injection groove 20 are pre-welded, which can avoid the situation of welding failure caused by the movement of materials during the formal welding process and improve the welding quality. Then, the sealing aluminum nail and the liquid injection groove 20 are formally welded to obtain a welded connection portion. And the sealing glue nail is still partially in the liquid injection through hole 10. At this time, if the welding of the sealing aluminum nail is poor, helium gas can escape from the recessed portion 106 of the sealing glue nail to the flow channel, and then escape from the welded connection portion to the outside of the sealing nail structure. Therefore, a helium leak detector is used to detect helium gas in the welded connection portion. If there is any leakage in the welded connection portion, the helium leak detector can quickly detect the presence of helium gas.

[0074] In an exemplary embodiment, the method further includes: when the detected value of the welded connection portion is lower than or equal to a preset threshold, applying pressure to the main body portion 202 of the second sealing nail 200 to push the first sealing nail 100 to embed and seal the liquid injection through hole 10; when the detected value of the welded connection portion is higher than the preset threshold, adjusting the welded connection portion and performing helium leak detection again after the adjustment.

[0075] Exemplarily, when the first sealing nail 100 partially enters the liquid injection through hole 10, the recessed portion 106 of the first sealing nail 100, the second surface of the main body portion 202, the inner wall of the liquid injection through hole 10, and the inner wall of the liquid injection groove 20 form a flow channel for helium gas.

[0076] During the helium leak detection process, the helium leak detection instrument will monitor the gas concentration at the welded joint in real time to determine the detection value of the welded joint. If the detection value of the welded joint is lower than or equal to the preset threshold, it indicates that the sealing performance of this part is good and there is no obvious gas leakage. At this time, when pressure is applied to the first surface, the deformation part 204 can generate deformation, enabling the second surface to push the first sealing nail 100 as a whole to be embedded and sealed in the liquid injection through hole 10, so as to eliminate the helium gas flow channel, thereby ensuring that the sealing effect of the liquid injection through hole 10 is more rigorous and enhancing the sealing performance. If the detection value of the welded joint is higher than the preset threshold, it means that there is a problem with the welding at the welded joint of the sealing aluminum nail. In this case, the welded joint needs to be adjusted, such as re-welding or further tightening the sealing nail, until the sealing meets the requirements. After the adjustment is completed, helium leak detection must be carried out again to confirm whether the repair measures are effective and ensure that the sealing performance meets the standards.

[0077] In this embodiment, this method combines a precise helium leak detection method with the pressing effect of the second sealing nail 200 to perform high-precision detection and repair of the sealing performance of the battery cell. Through this process, the sealing performance of the battery cell can be effectively ensured, preventing gas leakage or electrolyte overflow, and ensuring the safety and long-term performance of the battery.

[0078] It should be understood that although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the arrows, these steps do not necessarily need to be executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages. These steps or stages do not necessarily need to be executed at the same moment, but can be executed at different moments. The execution order of these steps or stages does not necessarily need to be sequential, but can be executed alternately or in turn with at least a part of the steps or stages in other steps or other steps.

[0079] In one embodiment, a computer device is provided, including a memory and a processor. A computer program is stored in the memory, and when the processor executes the computer program, the steps in the above method embodiments are implemented.

[0080] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0081] In one embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0082] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with relevant regulations.

[0083] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the various embodiments provided in this application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the various embodiments provided in this application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the various embodiments provided in this application can be general-purpose processors, central processors, graphics processors, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0084] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0085] The above embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. A sealing nail structure is applied to the liquid injection hole of a battery cell. The liquid injection hole includes a liquid injection groove and a liquid injection through hole opened on the liquid injection groove, and is characterized in that, The sealing nail structure includes: A first sealing nail that can be embedded in the liquid injection through hole; A second sealing nail, including a main body portion and a deformation portion; the main body portion can seal the liquid injection groove, the main body portion includes a first surface facing the first sealing nail and a second surface facing away from the first sealing nail; the deformation portion is provided on the first surface and the second surface; Wherein, when pressure is applied to the first surface, the deformation portion can generate deformation, so that the second surface can push the first sealing nail to integrally embed and seal in the liquid injection through hole.

2. The sealing nail structure according to claim 1, wherein, The first sealing nail includes a sealing portion and a guiding portion, and the guiding portion is fixedly connected to the sealing portion; the guiding portion is arranged in the liquid injection through hole, and under the action of pressure, the second surface can push the sealing portion into the liquid injection through hole, so that the sealing portion embeds and seals in the liquid injection through hole.

3. The sealing nail structure according to claim 2, wherein, The diameter of the sealing portion is larger than the aperture of the liquid injection through hole to be able to seal the liquid injection through hole.

4. The sealing nail structure according to claim 2, wherein A concave portion is arranged on the guiding portion along its axial direction; wherein, when the sealing portion does not enter the liquid injection through hole, the concave portion, the second surface, the inner wall of the liquid injection through hole and the inner wall of the liquid injection groove form a gas or liquid flow channel.

5. The sealing nail structure according to claim 4, wherein, The concave portion is a groove-shaped or spiral-shaped structure formed by the guiding portion extending along its own axial direction.

6. The sealing nail structure according to claim 1, characterized in that, The deformation portion of the second sealing nail is a groove structure arranged on the first surface and the second surface.

7. The sealing nail structure according to claim 1, characterized in that, The projection of the deformation portion in the direction perpendicular to the first surface or the second surface falls on the liquid injection groove.

8. A battery cell, characterized in that, Including the sealing nail structure according to any one of claims 1 to 7, the battery cell further includes a liquid injection hole, and the liquid injection hole includes a liquid injection groove and a liquid injection through hole; the liquid injection through hole is opened at the bottom of the liquid injection groove and penetrates into the interior of the battery cell.

9. A helium leak detection method, characterized in that, Applied to the sealing nail structure according to any one of claims 1 to 7; the method includes: Controlling the first sealing nail to partially enter the liquid injection through hole so that the liquid injection through hole can be passed by the inspection gas; Injecting helium gas into the interior of the battery cell; Welding the second sealing nail to the liquid injection groove to obtain a welded connection portion; Performing helium leak detection on the welded connection portion.

10. The method according to claim 9, wherein The method further includes: When the detection value of the welded connection portion is lower than or equal to a preset threshold, applying pressure to the main body portion of the second sealing nail to push the first sealing nail to embed and seal the liquid injection through hole; When the detection value of the welded connection portion is higher than the preset threshold, adjusting the welded connection portion and performing helium leak detection again after adjustment.

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