Battery sealing assembly and liquid injection hole assembly

Abstract

The utility model provides a battery sealing element and a liquid injection hole assembly, the battery sealing element is provided with an annular bulge and an annular groove, when the battery sealing element is sealed, the side wall of the annular bulge is firstly welded with a lower sealing nail for sealing a liquid injection hole, and then the side wall of the annular bulge is welded with an upper sealing nail for secondary welding at the annular groove for sealing the liquid injection hole. And the sealing nail at the lower part is sealed, so that a good sealing effect is realized. In addition, a protective patch is arranged in the annular groove in the liquid injection hole assembly, the liquid injection hole can be effectively isolated, and the defects of welding cracks, pinholes, explosion points and the like caused by the electrolyte problem in the welding process are overcome. Meanwhile, the structural design can ensure that the current welding mode is not changed, the novel sealing nail can be adopted for secondary welding when bad conditions occur, and the reliability of secondary laser welding is effectively improved.

Description

Technical Field

[0001] The utility model relates to the field of solar cell sealing, in particular to the related fields of a battery sealing assembly and a liquid injection hole assembly. Background Art

[0002] A liquid injection hole for injecting electrolyte into an electric core is provided on the end cover of a lithium-ion power battery and an energy storage battery. After the liquid injection is completed, the liquid injection hole needs to be sealed. The sealing form of the liquid injection hole mainly adopts a combination form of an interference fit between a sealing glue nail and the liquid injection hole and laser welding of the sealing nail. In this sealing method during welding, pulse laser welding, continuous laser welding or QCW laser welding is often used. Due to residual electrolyte, surface dirt, foreign objects, welding parameter problems, etc. in the liquid injection hole, welding cracks and pinholes are caused, resulting in poor battery packaging and triggering the risk of internal short circuit of the electric core, greatly affecting the use safety of the electric core. To ensure the safety of the electric core, welding quality inspection is extremely important. With the increase in the capacity of the electric core and the rise in the manufacturing cost of a single electric core, improving the welding excellent rate is crucial for cost reduction and efficiency improvement.

[0003] At present, there are mainly the following several ways to seal the liquid injection hole in the market: 1. The sealing nail adopts the style of a steel ball for sealing; there will be problems with the clearance fit accuracy when using the steel ball type sealing method, resulting in defects. 2. Sealing in the form of applying glue; when using this method, the product quality needs to be downgraded and the manufacturing excellent rate cannot be improved. 3. For a defective welded electric core, it is re-welded by using a repair milling cutter; when using this method, there is a possibility that aluminum chips will fall into the electric core during the processing, affecting the safety of the electric core.

[0004] Therefore, it is urgent to invent a battery sealing member and a liquid injection hole assembly to effectively solve the above technical problems. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a battery sealing assembly and a liquid injection hole assembly to effectively solve the technical problem of low excellent rate in the sealing nail welding process. Moreover, the technical problems that the utility model can also solve are: improving the evacuation rate of the electric core during the helium leak detection process, accelerating the overflow of moisture during the electric core baking process, quickly injecting electrolyte during the liquid injection process, and quickly extracting internal gas of the electric core.

[0006] To achieve the above purpose, the utility model provides a battery sealing assembly, including:

[0007] An annular protrusion, which is arranged around the periphery of the liquid injection hole;

[0008] An annular groove, which is arranged around the periphery of the annular protrusion;

[0009] A lower sealing nail, which is arranged inside the annular protrusion to seal the liquid injection hole;

[0010] The upper sealing nail is arranged on the annular groove to seal the lower sealing nail.

[0011] Furthermore, the upper sealing nail includes an outer edge of the sealing nail and an inner edge of the sealing nail, and the outer edge of the sealing nail is located outside the inner edge of the sealing nail.

[0012] Furthermore, the upper sealing nail further includes a skirt of the sealing nail, which is arranged below the outer edge of the sealing nail.

[0013] Furthermore, stress grooves are provided around the skirt of the sealing nail for absorbing and dispersing the stress generated during the welding process, and the depth of the stress grooves is 0.55 mm.

[0014] Furthermore, the width range of the annular protrusion is 6 - 12 mm.

[0015] Furthermore, an annular sink is provided between the annular protrusion and the liquid injection hole, and the lower sealing nail covers the annular sink.

[0016] Furthermore, a groove of the sealing nail is provided on the inner edge of the sealing nail, and the groove of the sealing nail is used to cover and accommodate the lower sealing nail.

[0017] Furthermore, the depth range of the groove of the sealing nail is 0.15 - 0.3 mm.

[0018] Furthermore, the outer shape width of the sealing nail is greater than or equal to 7.6 mm and less than or equal to 16 mm.

[0019] The present utility model further provides a liquid injection hole assembly, including:

[0020] An annular protrusion, which is arranged around the periphery of the liquid injection hole;

[0021] An annular groove, which is arranged around the periphery of the annular protrusion;

[0022] A protective patch, which is arranged on the annular groove for sealing the annular groove.

[0023] Furthermore, the size range of the liquid injection hole is 3 - 8 mm.

[0024] Compared with the prior art, the beneficial effects of the present utility model are mainly reflected in providing a battery seal and a liquid injection hole assembly. The battery seal is provided with an annular protrusion and an annular groove. When sealing, first, a primary welding is performed between the side wall of the annular protrusion and the lower sealing nail to seal the liquid injection hole. Then, a secondary welding is performed between the annular groove and the upper sealing nail to seal the lower sealing nail, thereby achieving a good sealing effect. In addition, a protective patch is provided in the annular groove of the liquid injection hole assembly, which can effectively isolate the liquid injection hole and avoid defects such as welding cracks, pinholes, and explosion points caused by electrolyte problems during welding. At the same time, this structural design can ensure that the current welding mode remains unchanged. When a bad situation occurs, a new type of sealing nail can be used for secondary welding, effectively improving the reliability of secondary laser welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic cross-sectional view of the welding of the upper sealing nail and the end cover liquid injection hole in an embodiment of the present utility model;

[0026] Figure 2 is a three-dimensional view of the top cover liquid injection hole in an embodiment of the present utility model;

[0027] Figure 3 is a top view of the top cover liquid injection hole with a protective patch in an embodiment of the present utility model;

[0028] Figure 4 is a schematic view of the upper sealing nail in an embodiment of the present utility model;

[0029] Figure 5 is a three-dimensional schematic view of the upper sealing nail in an embodiment of the present utility model;

[0030] Figure 6 is a schematic flow chart of the specific use of the protective patch in an embodiment of the present utility model.

[0031] In the figure, 1, annular protrusion; 11, annular sink; 12, primary welding location; 2, annular groove; 21, secondary welding location; 31, sealing nail outer edge; 32, stress groove; 33, sealing nail inner edge; 34, sealing nail groove; 35, sealing nail skirt; 4, liquid injection hole; 5, protective patch. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following will describe in more detail a battery seal and an end cover liquid injection hole of the present utility model with reference to the accompanying drawings, which show the preferred embodiments of the present utility model. It should be understood that those skilled in the art can modify the present utility model described herein while still achieving the beneficial effects of the present utility model. Therefore, the following description should be understood as a broad guidance for those skilled in the art and not as a limitation on the present utility model.

[0033] The present utility model will be described more specifically by way of example with reference to the accompanying drawings in the following paragraphs. According to the following description, the advantages and features of the present utility model will be clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the embodiments of the present utility model.

[0034] Embodiment 1

[0035] As Figure 1 、 Figure 3 and 4 shown, this embodiment provides a battery sealing assembly, including: an annular protrusion 1, which is arranged around the periphery of the liquid injection hole 4; an annular groove 2, which is arranged around the periphery of the annular protrusion 1; a lower sealing nail (not shown in the figure), which is arranged inside the annular protrusion 1 to seal the liquid injection hole 4; and an upper sealing nail, which is arranged on the annular groove 2 to seal the lower sealing nail.

[0036] As Figure 4 and Figure 5 shown, in this embodiment, the upper sealing nail further includes a sealing nail outer edge 31 and a sealing nail inner edge 33, and the sealing nail outer edge 31 is located outside the sealing nail inner edge 33.

[0037] Furthermore, the upper sealing nail further includes a sealing nail skirt 35, which is arranged below the sealing nail outer edge 31.

[0038] Furthermore, a stress groove is provided around the sealing nail skirt for absorbing and dispersing the stress generated during the welding process; the depth of the stress groove is 0.55 mm, and the diameter near the sealing nail outer edge 31 is 2.2 mm.

[0039] Specifically, the outer edge of the lower sealing nail contacts the inner edge of the annular protrusion 1, and a primary welding is performed at the primary welding joint 12; after detecting that there is a problem of poor welding or liquid leakage at the primary welding joint 12, the upper sealing nail is then welded to the annular groove 2 through the secondary welding joint 21.

[0040] Specifically, when performing secondary welding on the liquid injection hole 4, the stress groove 32 can absorb and disperse the stress generated during the welding process, so that it will not concentrate in the narrow weld area. This can not only improve the welding quality and reliability, but also ensure the subsequent use safety of the battery.

[0041] Furthermore, the width range of the annular protrusion 1 is 6 - 12 mm, for example, 8 mm, and the width range of the annular protrusion 1 meets the requirements of the current normal liquid injection production process.

[0042] By setting a reasonable width, it can not only meet the requirements of the production process, but also ensure the smooth progress of the subsequent formation process, thereby ensuring the stability and reliability of the entire battery manufacturing process.

[0043] As Figure 2 shown, in a specific example, an annular sink 11 is provided between the annular protrusion 1 and the liquid injection hole 4, and the lower sealing nail covers the annular sink 11. Due to the provision of the annular sink 11, during the liquid injection and formation processes, the formation nozzle and the liquid injection hole 4 can be well avoided and do not interfere with each other.

[0044] In this example, the annular groove 2 is a sunken circular ring type, which is convenient for placing the protection gasket and is also convenient for the subsequent upper sealing nail to perform secondary welding on the annular groove 2.

[0045] In this example, a sealing nail groove 34 is provided on the inner edge 33 of the sealing nail, and the sealing nail groove 34 is used to cover and accommodate the lower sealing nail.

[0046] The function of setting the above-mentioned sealing nail groove 34 is to provide a groove for accommodating the convexity formed by the electrolyte splashed out during the previous filling process (the irregular convexity formed on the surface of the lower sealing nail during the welding process), so that the inner edge 33 of the sealing nail fits more closely with the top cover liquid injection hole. When the first sealing nail welding detection is NG (unqualified) and secondary welding is required, the internal structure of the upper sealing nail can avoid the surface of the first weld. The internal height range of the upper sealing nail is 0.15 - 0.3 mm, for example, 0.2 mm, and the inner edge diameter is 2 - 4 mm wider than the diameter of the annular protrusion 1, for example, 3 mm to meet the full cooperation and positioning of the upper sealing nail welding during secondary laser welding.

[0047] Furthermore, the outer shape width of the upper sealing nail is greater than or equal to 7.6 mm and less than or equal to 16 mm.

[0048] Furthermore, the outer shape height of the upper sealing nail is controlled to be 1.6 mm higher than the upper surface of the top cover end plate. This height is lower than the 5 - mm - high pole column, and the use of the protection patch 5 for protection does not affect the external structure design of the battery cell.

[0049] In this embodiment, the size of the liquid injection hole 4 is also modified: Generally, in the prior art, the diameter of the liquid injection hole 4 is generally less than 3 mm. In this embodiment, the diameter range of the liquid injection hole 4 is 3 - 8 mm, and the preferred diameter is 5.5 mm. By the above improvement of the diameter of the liquid injection hole 4, by using the liquid injection hole 4 with this size, during the filling process, the design of the size of the liquid injection hole 4 is not affected by the external shape structure of the battery cell, ensuring smooth filling.

[0050] Increasing the diameter of the liquid injection hole 4 is beneficial to improving the flow rates of gas and liquid, meeting the requirements of the large-capacity battery cell manufacturing process.

[0051] In subsequent processes such as helium leak detection and baking of the battery cell, an appropriate size of the liquid injection hole 4 can ensure the effective discharge of gas and moisture inside the battery cell.

[0052] During the liquid injection process of the battery cell, when injecting a large-capacity electrolyte of 1 - 5 kg, a liquid injection hole 4 with a diameter of 5.5 mm can provide sufficient breathing channels to ensure the smooth injection of the electrolyte without the generation of bubbles.

[0053] In summary, through the optimized design of the diameter of the liquid injection hole 4, it can effectively meet the requirements of various process links in battery manufacturing, ensuring the stability and reliability of the production process.

[0054] In summary, this embodiment proposes a battery seal, in which the battery seal is provided with an annular protrusion 1 and an annular groove 2. When performing sealing, first, a primary welding is carried out between the side wall of the annular protrusion 1 and the lower sealing nail to seal the liquid injection hole 4, and then a secondary welding is carried out at the annular groove 2 with the upper sealing nail to seal the lower sealing nail, thereby achieving a good sealing effect.

[0055] Embodiment 2

[0056] In this embodiment, a liquid injection hole assembly is provided, which can be used in cooperation with the sealing assembly in Embodiment 1. Specifically, the liquid injection hole assembly includes: an annular protrusion 1, which is arranged around the periphery of the liquid injection hole 4; an annular groove 2, which is arranged around the periphery of the annular protrusion 1; and a protective patch 5, which is arranged on the annular groove 2.

[0057] Specifically, the annular protrusion 1 and the annular groove 2 are the same as those in Embodiment 1. For specific reference, please refer to the description in Embodiment 1 and will not be elaborated here.

[0058] Among them, the protective patch 5 can be made of a material with a protective function, and its size is a circular ring type adapted to the annular groove 2, and is used to seal the annular groove.

[0059] During the electrolyte injection process, the protective patch 5 can effectively isolate the annular groove 2 to prevent the electrolyte from contaminating this area.

[0060] Furthermore, the diameter range of the liquid injection hole 4 is 3 - 8 mm, and the preferred diameter is 5.5 mm.

[0061] For a better understanding of the present invention, as Figure 6 shown, the process of the specific use of the protective patch 5 is as follows:

[0062] Step 1: When manufacturing the top cover, the annular groove 2 is pasted with the protective patch 5;

[0063] Step 2: Perform primary welding on the liquid injection hole of the top cover;

[0064] Step 3: Conduct visual inspection on the result of the primary welding. If the inspection is qualified, proceed to Step 9; otherwise, proceed to Step 4;

[0065] Step 4: The repair worker performs repair welding. If the inspection is qualified after the repair welding, proceed to Step 9; otherwise, proceed to Step 5;

[0066] Step 5: Peel off the protective patch 5 at the annular groove 2;

[0067] Step 6: Perform secondary welding at the annular groove 2;

[0068] Step 7: Check the welding appearance again. If the inspection is qualified, proceed to Step 9; otherwise, proceed to Step 8;

[0069] Step 8: The repair worker performs repair welding. If the inspection is qualified after the repair welding, proceed to Step 9;

[0070] Step 9: Conduct ammonia inspection production for the processes under normal transfer.

[0071] It should be noted that the liquid injection hole assembly proposed in this embodiment and the seal in Embodiment 1 are mainly applied to the manufacturing of large-capacity battery cells with a capacity of 300 - 1000 AH (including square batteries, cylindrical batteries, and blade batteries).

[0072] To sum up, the battery seal and liquid injection hole assembly proposed by the present utility model have the following performance:

[0073] New design of the end - cover liquid injection hole: A protective patch is provided on the annular groove, which can effectively isolate the liquid injection hole and avoid defects such as welding cracks, pinholes, and explosion points caused by electrolyte problems during welding. At the same time, this structural design can ensure that the current welding mode remains unchanged. When problems occur, a new type of sealing nail can be used for secondary welding, effectively improving the reliability of secondary laser welding. Specifically, a stress groove is provided in the annular groove, which can effectively absorb and disperse welding stress during the laser welding process, avoiding weld cracking caused by stress concentration. The above - mentioned structural design can not only improve the welding quality but also ensure the safety of the battery during subsequent use.

[0074] Optimization of the liquid injection hole size: Increasing the diameter of the liquid injection hole to the range of 3 - 8 mm is beneficial for quickly completing processes such as electrolyte injection, helium leak detection vacuum suction, and baking moisture overflow for 300 - 1000 Ah batteries, meeting the manufacturing requirements of large-capacity battery cells. Through the optimized design of the liquid injection hole diameter, it can not only meet the process requirements of each link in battery manufacturing but also ensure the flow performance of gas and liquid. For example, in the battery cell liquid injection process, a liquid injection hole diameter of 5.5 mm can provide sufficient breathing channels, enabling the smooth injection of 1 - 5 kg of large-capacity electrolyte without the generation of bubbles. At the same time, the appropriate liquid injection hole size can also ensure the effective discharge of internal gas and moisture during the subsequent helium leak detection and baking processes of the battery cell, improving product quality.

[0075] Improvement of comprehensive performance: Through the above innovative design, not only can various defects during battery cell manufacturing be reduced, and the product qualification rate be improved, but also the overall use safety of the battery is significantly enhanced. Specifically, during the design process, the inventor fully considered the characteristics of the battery manufacturing process and the requirements of the use environment. On the one hand, the new end cap liquid injection hole structure and the optimized liquid injection hole size can effectively avoid the generation of welding defects and reduce the defect rate during manufacturing; on the other hand, these innovative designs also ensure the safety performance of the battery during use. For example, during key processes such as helium leak detection and baking of the battery cell, harmful gases and moisture can be reliably discharged, improving the overall quality of the battery.

[0076] In summary, the battery seal and liquid injection hole assembly of the present utility model give full play to the optimization in terms of structure, size, etc., achieving a double improvement in manufacturing reliability and product performance, and bringing a positive technical contribution to the battery industry.

[0077] It should be understood that the above specific embodiments of the present utility model are only used for exemplary illustration or explanation of the principle of the present utility model, and do not constitute a limitation to the present utility model. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present utility model shall be included within the protection scope of the present utility model. In addition, the appended claims of the present utility model are intended to cover all changes and modification examples falling within the scope and boundary of the appended claims, or equivalent forms of such scope and boundary.

Claims

1. A battery sealing assembly, characterized in that: include: An annular protrusion is disposed around the periphery of the injection hole; An annular groove is disposed around the periphery of the annular protrusion; A lower sealing pin is arranged inside the annular protrusion to seal the injection hole; The upper sealing pin is arranged on the annular groove to seal the lower sealing pin.

2. The battery sealing assembly according to claim 1, characterized in that: The upper sealing nail comprises a sealing nail outer edge and a sealing nail inner edge, and the sealing nail outer edge is located outside the sealing nail inner edge.

3. The battery sealing assembly according to claim 2, characterized in that: The upper sealing pin also includes a sealing pin skirt, which is arranged below the outer edge of the sealing pin.

4. The battery sealing assembly according to claim 3, characterized in that: Stress grooves are arranged around the skirt edge of the sealing nail to absorb and disperse the stress generated during the welding process.

5. The battery sealing assembly according to claim 4, characterized in that: The depth of the stress groove is 0.55 mm.

6. The battery sealing assembly according to claim 1, characterized in that: The width of the annular protrusion is in the range of 6-12 mm.

7. The battery sealing assembly according to claim 2, characterized in that: An annular recessed groove is provided between the annular protrusion and the liquid injection hole, and the lower sealing nail covers the annular recessed groove.

8. The battery sealing assembly according to claim 7, characterized in that: A sealing nail groove is provided on the inner edge of the sealing nail, and the sealing nail groove is used to cover and accommodate the lower sealing nail.

9. The battery sealing assembly according to claim 8, characterized in that: The depth of the sealing nail groove ranges from 0.15 to 0.3 mm.

10. The battery sealing assembly according to claim 1, characterized in that: The outer width of the upper sealing nail is greater than or equal to 7.6 mm and less than or equal to 16 mm.

11. A liquid injection hole assembly, characterized in that: include: An annular protrusion is disposed around the periphery of the injection hole; An annular groove is disposed around the periphery of the annular protrusion; A protective patch is arranged on the annular groove and is used for sealing the annular groove.

12. A liquid injection hole assembly according to claim 11, characterized in that: The size of the injection hole ranges from 3 to 8 mm.

Images