Built-in helium filling leak detection device for battery cell

Abstract

The utility model discloses a built-in helium-filled leak detection device for a battery cell, which comprises a battery cell shell, a battery cell body and a helium gas bag are respectively and fixedly arranged in the battery cell shell, and the helium gas bag is in contact with the battery cell body. According to the utility model, the helium gas bag is arranged inside the battery cell body, after the battery cell body is filled with electrolyte through the liquid injection port, the liquid injection port is sealed, and the outside of the battery cell shell is vacuumized, so that if the battery cell body leaks, the helium gas bag leaks, and helium gas can be detected, otherwise, the helium gas can not be detected; in the subsequent use process of the battery cell, if the leakage condition of the battery cell body needs to be detected, a mode of detecting helium after vacuumizing can be adopted at any time for detection, the helium filling operation in the battery cell is canceled, long-term leakage problem monitoring of the battery cell can be realized, the use safety of the battery cell is improved, and the safety of the battery cell is improved. And the safety risk caused by leakage of the battery cell is reduced.

Description

Technical Field

[0001] This utility model relates to the field of battery cell leak detection technology, and in particular to a battery cell built-in helium gas leak detection device. Background Technology

[0002] As the core component of a battery, the integrity of the battery cell is crucial during electrolyte injection manufacturing and subsequent use. However, due to various factors, battery cells may leak. During the manufacturing stage, unreasonable or lax production processes, such as poor sealing or welding, can lead to decreased cell sealing and subsequent electrolyte leakage. Furthermore, inappropriate material selection, such as substandard separators or positive and negative electrode materials, can also cause leakage due to their inability to withstand pressure changes during cell operation. Equipment malfunctions, such as insufficient sealing machine pressure or mold wear, can also result in incomplete cell sealing, increasing the risk of leakage. During subsequent use, design flaws and external damage, such as compression or impact, can also cause the battery casing to crack or the sealing structure to fail, leading to electrolyte leakage. Electrolyte leakage not only reduces battery capacity and affects normal battery use but can also corrode internal battery components, further exacerbating battery performance degradation and even causing safety issues such as short circuits and fires.

[0003] To ensure the sealing and safety of battery cells, helium detection technology is used in the current battery cell manufacturing process. This technology involves filling the battery cell with a certain amount of helium gas and then using a helium detector to create an external vacuum to detect any leaks. Helium is an inert gas that does not readily react with other substances and has a lower density than air, allowing it to easily seep through tiny pores, making it suitable for high-precision airtightness testing. In the battery cell manufacturing process, this technology is mainly used for inspecting the sealing of the casing welds before liquid injection and for dry leak testing of the finished battery cells after liquid injection and sealing nail welding. The former uses a positive pressure helium detection method, where the battery cell casing is first evacuated, filled with helium, and sealed, then placed in a vacuum testing chamber to measure the amount of helium leaking. The latter uses a negative pressure helium detection method, utilizing pre-sealed helium gas inside the battery or filling the battery with helium, and detecting whether helium leaks out from the outside of the battery to determine if there are any leaks inside. Helium detection technology, with its high sensitivity, rapid response, and non-destructive testing characteristics, ensures the sealing and safety of battery cells and is an indispensable part of the power battery manufacturing process.

[0004] However, existing helium-filling testing methods have the following shortcomings. First, this technology requires repeated helium-filling operations inside the cell, which carries the risk of introducing foreign objects into the cell, potentially affecting its performance and safety. Second, performing helium-filling testing after electrolyte injection may cause electrolyte leakage, resulting in waste and potential contamination, posing a potential threat to both the production environment and the cell itself. Finally, existing technologies cannot effectively identify and monitor leaking cells over a long period, meaning that leaks may not be detected and addressed promptly, increasing battery safety risks. Utility Model Content

[0005] The purpose of this invention is to provide a battery cell-embedded helium gas leak detection device to address the aforementioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a battery cell built-in helium-filled leak detection device, comprising a battery cell shell, wherein a battery cell body and a helium gas bladder are fixedly installed inside the battery cell shell, the helium gas bladder is in contact with the battery cell body, a top cover is fixedly installed on the top of the battery cell shell, a pressure relief valve is provided on the top of the helium gas bladder, a sealing cover is provided on the pressure relief valve, an inflation port and a liquid injection port are respectively provided on the top of the top of the helium gas bladder and the top of the battery cell body, and a heat dissipation component is provided on one side of the battery cell body.

[0007] As a further description of the above technical solution: both the top of the air inlet and the liquid injection inlet are provided with sealing plates.

[0008] As a further description of the above technical solution: the heat dissipation component includes multiple heat dissipation fins, which are fixedly installed on the side wall of the battery cell housing, and the multiple heat dissipation fins are in contact with the helium gas bag.

[0009] As a further description of the above technical solution: the outer surface of the battery cell body is provided with a thermally conductive coating.

[0010] As a further description of the above technical solution: a counterweight is fixedly installed inside the battery cell casing, and the counterweight is positioned directly below the helium gas bladder.

[0011] This invention provides a helium-filled leak detection device for battery cells. It offers the following advantages: a helium gas bladder is installed inside the battery cell. After the battery cell is filled with electrolyte through the injection port, the injection port is sealed. By evacuating the battery cell casing, if a leak occurs in the battery cell, the helium gas bladder will leak, thus detecting helium. Conversely, no helium will be detected. Furthermore, during subsequent use of the battery cell, if leakage detection is needed, it can be performed at any time by evacuating and detecting helium, eliminating the need for internal helium filling. This allows for long-term monitoring of battery cell leaks, improving battery cell safety and reducing safety risks caused by leaks.

[0012] It should be understood that the foregoing general description and the following detailed description are exemplary and illustrative only, and are not intended to limit this disclosure.

[0013] This application provides an overview of various implementations or examples of the technology described in this disclosure, and is not a full disclosure of the entire scope or all features of the disclosed technology. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall three-dimensional structure of a battery cell built-in helium-filled leak detection device proposed in this utility model.

[0015] Figure 2 This is a three-dimensional structural schematic diagram from another perspective of the present invention;

[0016] Figure 3 This is a three-dimensional exploded structural diagram of the present invention;

[0017] Figure 4 This is a cross-sectional structural diagram of the present invention.

[0018] Legend:

[0019] 1. Battery cell casing; 2. Liquid injection port; 3. Gas filling port; 4. Battery cell body; 5. Helium gas bladder; 6. Pressure relief valve; 7. Sealing cap; 8. Sealing plate; 9. Top cover; 10. Heat dissipation fins; 11. Counterweight; 12. Thermally conductive coating. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0021] Reference Figure 1-4A battery cell-embedded helium leak detection device includes a battery cell housing 1. A battery cell body 4 and a helium gas bladder 5 are fixedly installed inside the battery cell housing 1, with the helium gas bladder 5 in contact with the battery cell body 4. A top cover 9 is fixedly installed at the top of the battery cell housing 1. A pressure relief valve 6 is provided at the top of the helium gas bladder 5, and a sealing cover 7 is provided on the pressure relief valve 6. An inflation port 3 and a liquid injection port 2 are respectively located at the top of the helium gas bladder 5 and the battery cell body 4. A heat dissipation component is provided on one side of the battery cell body 4. Helium gas is disposed inside the battery cell body 4. The helium gas bladder 5 is used to fill the battery cell body 4 with electrolyte through the injection port 2 and then seal the injection port 2. By performing a vacuum operation on the outside of the battery cell shell 1, if the battery cell body 4 leaks, the helium gas bladder 5 will leak, and helium can be detected. Otherwise, helium will not be detected. Furthermore, if it is necessary to detect leakage in the battery cell body 4 during subsequent use, the leakage can be detected at any time by vacuuming and then detecting helium, eliminating the need for helium filling inside the battery cell. This enables long-term monitoring of leakage problems in the battery cell, improves the safety of battery cell use, and reduces the safety risks caused by leakage.

[0022] As a preferred technical solution in this embodiment, a sealing plate 8 is provided at the top of both the inflation port 3 and the liquid injection port 2; the sealing plate 8 can seal the inflation port 3 and the liquid injection port 2 to prevent leakage of the helium gas bag 5 and the electrolyte.

[0023] As a preferred technical solution in this embodiment, the heat dissipation component includes a plurality of heat dissipation fins 10, which are fixedly installed on the side wall of the battery cell housing 1. The plurality of heat dissipation fins 10 are in contact with the helium gas bag 5. Helium has good thermal conductivity, and the helium gas bag 5 can achieve the leak detection effect while conducting the heat generated by the battery cell body 4 through the helium gas, thereby increasing the heat dissipation performance.

[0024] As a preferred technical solution in this embodiment, a thermally conductive coating 12 is provided on the outside of the battery cell body 4; the thermally conductive coating 12 can effectively dissipate the heat generated by the battery cell body 4 through the thermally conductive coating 12.

[0025] As a preferred technical solution in this embodiment, a counterweight 11 is fixedly installed inside the battery cell housing 1, and the counterweight 11 is located directly below the helium gas bag 5. Since the mass of the helium gas bag 5 is small, it will cause uneven mass distribution of the entire battery cell and poor stability. By setting the counterweight 11, the stability of the battery cell housing can be enhanced.

[0026] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A battery cell-embedded helium-filled leak detection device, comprising a battery cell casing (1), characterized in that, Inside the battery cell housing (1), the battery cell body (4) and the helium gas bag (5) are fixedly installed respectively. The helium gas bag (5) is in contact with the battery cell body (4). A top cover (9) is fixedly installed on the top of the battery cell housing (1). A pressure relief valve (6) is provided on the top of the helium gas bag (5). A sealing cover (7) is provided on the pressure relief valve (6). An inflation port (3) and a liquid injection port (2) are provided on the top of the top of the top cover (9). The inflation port (3) and the liquid injection port (2) are respectively located on the top of the helium gas bag (5) and the battery cell body (4). A heat dissipation component is provided on one side of the battery cell body (4).

2. The battery cell built-in helium gas leak detection device according to claim 1, characterized in that, The top of both the air inlet (3) and the liquid injection inlet (2) are provided with sealing plates (8).

3. The battery cell built-in helium gas leak detection device according to claim 1, characterized in that, The heat dissipation assembly includes multiple heat dissipation fins (10), which are fixedly installed on the side wall of the battery cell housing (1) and are in contact with the helium gas bag (5).

4. The battery cell built-in helium-filled leak detection device according to claim 1, characterized in that, The outer surface of the battery cell body (4) is provided with a thermally conductive coating (12).

5. The battery cell built-in helium-filled leak detection device according to claim 1, characterized in that, A counterweight (11) is fixedly installed inside the battery cell casing (1), and the counterweight (11) is located directly below the helium gas bag (5).

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