Housing assembly and battery

Abstract

The utility model provides a kind of shell assembly and battery.The shell assembly includes: shell, with installation cavity, shell includes at least one side wall, the top of the inner wall surface of at least one side wall is provided with protrusion, protrusion is located in installation cavity, protrusion and the top surface of the side wall where it is located have first preset distance L1.The utility model technical scheme, can reduce when carrying out top cover welding, the probability that part laser beam can enter shell and ablate battery material.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more specifically, to a housing assembly and a battery. Background Technology

[0002] Lithium-ion batteries, due to their energy density, low self-discharge rate, lack of memory effect, and environmental friendliness, have become an indispensable energy supply core in consumer electronics, electric vehicles, energy storage systems, and even aerospace. However, with the widespread application of lithium-ion batteries in various fields, the requirements for the precision and safety of their manufacturing processes are also increasing. Among these processes, the welding of the top cover after the battery cell is installed is a key step in ensuring the performance of the finished battery. Through high-precision sealing welding, the top cover is tightly bonded to the battery casing (especially the square aluminum casing), aiming to ensure the battery's mechanical strength, airtightness, and reliability of electrical connections. This is a crucial step in the lithium-ion battery manufacturing process.

[0003] Currently, the welding process for the top cover mainly employs laser welding technology. Robots or fixtures are used for positioning to ensure the gap between the top cover and the housing is within 0.1mm. Then, appropriate welding parameters are used for continuous laser welding on all four sides. However, during the welding process, some of the laser beam may enter the housing and come into contact with the battery cells installed inside. Laser beams entering the housing can ablate the battery cell materials (e.g., electrodes, separators, tabs, or insulating films), leading to problems such as short circuits and electrolyte contamination. Utility Model Content

[0004] The main purpose of this invention is to provide a housing assembly and battery that can reduce the probability that some laser beams may enter the housing and ablate the battery cell material during top cover welding.

[0005] To achieve the above objectives, according to one aspect of the present invention, a housing assembly is provided, comprising: a housing having a mounting cavity, the housing including at least one sidewall, a protrusion being provided on the top of the inner wall surface of the at least one sidewall, the protrusion being located within the mounting cavity, and a first preset distance L1 being between the protrusion and the top surface of the sidewall where it is located.

[0006] Furthermore, the housing assembly also includes a top cover, which is connected to the top surface of the housing, and the bottom surface of the top cover has a second preset distance from the protrusion.

[0007] Furthermore, the first preset distance L1 is in the range of 0.05mm≤L1≤0.5mm.

[0008] Furthermore, the first preset distance L1 is in the range of 0.1mm≤L1≤0.3mm.

[0009] Furthermore, there are four side walls, and the shell also includes a bottom wall. The four side walls are perpendicular to the bottom wall and connected to the bottom wall. The four side walls are connected in sequence along the circumference of the bottom wall and together form an installation cavity. The ends of the four side walls away from the bottom wall together form a rectangular opening, which communicates with the installation cavity. The top of the inner wall surface of the four side walls is provided with a protrusion.

[0010] Furthermore, the four protrusions are connected end to end and located on the same horizontal plane.

[0011] Furthermore, the cross-section of the protrusion can be any one of arch, semi-circle, or polygon, and the maximum protrusion height of the protrusion relative to its side wall is L2, with the value of L2 ranging from 0.03mm to 0.08mm.

[0012] Furthermore, the raised outer surface is coated with a coating that is configured to absorb a portion of the laser beam.

[0013] Furthermore, the protrusion and its surrounding sidewall are integrally formed; and / or, the protrusion is made of ceramic or aluminum.

[0014] According to another aspect of the present invention, a battery is provided, comprising: a battery cell; and a housing assembly as described above, wherein the battery cell is mounted within a mounting cavity.

[0015] The present invention provides a housing and a top cover. At least one side wall of the housing has a protrusion on its top surface. The protrusion is at a first preset distance from the top surface of the side wall. The protrusion can block the laser beam that enters the mounting cavity from the gap between the top cover and the top surface of the housing and irradiates the area where the protrusion is located. This prevents the laser beam that enters the mounting cavity and irradiates the area where the protrusion is located from contacting the battery cell. This avoids the laser beam that enters the mounting cavity and irradiates the area where the protrusion is located from ablating the battery cell (e.g., burning the electrode, diaphragm, tab, or insulating film of the battery cell), which could lead to problems such as short circuit of the battery cell and electrolyte contamination. Attached Figure Description

[0016] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments and descriptions of this utility model are used to explain this utility model and do not constitute an undue limitation thereof. In the drawings:

[0017] Figure 1 A schematic diagram of the structure of a prior art housing is shown;

[0018] Figure 2 A schematic diagram of the housing structure according to an embodiment of the present invention is shown;

[0019] Figure 3 A schematic diagram of the structure of a battery according to an embodiment of the present invention is shown.

[0020] The above figures include the following reference numerals:

[0021] 10. Housing; 11. Mounting cavity; 12. Side wall; 13. Bottom wall; 14. Rectangular opening; 20. Protrusion; 30. Battery cell; 40. Prior art housing. Detailed Implementation

[0022] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] In existing technologies for welding the cell top cover to the aluminum shell, the laser beam may be scattered or refracted due to material reflection, assembly gaps, or welding path deviations. Part of the laser beam may enter the shell and contact the cell, leading to problems such as cell material ablation, short circuits, or electrolyte contamination. Traditional solutions have limitations. For example, adjusting laser parameters, mainly by reducing power, may sacrifice weld strength and cause poor sealing; adding a protective layer design, such as applying high-temperature resistant tape to the electrode surface, increases process complexity and prevents reuse; optimizing fixture design to reduce gaps through precise positioning requires extremely high equipment precision and significantly increases costs.

[0024] To solve the above problems, see [reference] Figure 2 and Figure 3 As shown, the present invention provides a housing assembly, which includes: a housing 10 having a mounting cavity 11, the housing 10 including at least one side wall 12, the top of the inner wall surface of at least one side wall 12 being provided with a protrusion 20, the protrusion 20 being located in the mounting cavity 11, and a first preset distance L1 between the protrusion 20 and the top surface of the side wall 12 where it is located.

[0025] In this embodiment, the mounting cavity 11 is used to mount the battery cell 30. The protrusion 20 is located inside the mounting cavity 11, and there is a first preset distance between the protrusion 20 and the top surface of the side wall 12 where it is located. That is, the protrusion 20 is located below the top surface of the side wall 12, and there is a first preset distance between the protrusion 20 and the top surface of the side wall 12 where it is located. This ensures that the protrusion 20 can block the laser beam that enters the mounting cavity 11 from the gap between the top cover and the top surface of the housing 10 and irradiates the area where the protrusion 20 is located, so as to avoid the laser beam entering the mounting cavity 11 and irradiating the area where the protrusion 20 is located from contacting the battery cell 30. This can prevent the laser beam entering the mounting cavity 11 and irradiating the area where the protrusion 20 is located from ablating the battery cell 30 (e.g., burning the electrode, separator, tab or insulating film of the battery cell, etc.) and causing problems such as short circuit of the battery cell and electrolyte contamination, thereby improving the safety performance of the battery cell 30.

[0026] In addition, in the prior art, in order to prevent some laser beams from entering the housing 10 and damaging the battery cell 30, it is necessary to adjust the laser parameters, add a protective layer, or optimize the fixture design. However, with the housing assembly of this application, the above-mentioned operations are not required, nor are additional consumables (such as high-temperature resistant tape). It can ensure welding strength and sealing, avoid increasing process complexity, reduce the precision requirements of the equipment, and reduce production costs.

[0027] It should be noted that if the top of the inner wall surface of all the side walls 12 of the housing 10 is provided with a protrusion 20, it can block all laser beams entering the mounting cavity 11 from the gap between the top cover and the top surface of the housing 10. If the top of the inner wall surface of some of the side walls 12 of the housing 10 is provided with a protrusion 20, it can only prevent the laser beam entering the mounting cavity 11 and irradiating the area where the protrusion 20 is located from contacting the cell 30.

[0028] In addition, the housing assembly of this application has the following advantages:

[0029] 1) The protrusion 20 can physically isolate the welding position of the top cover from the outer surface of the cell 30. The laser beam can only irradiate the protrusion 20 and cannot directly irradiate or reflect to the area where the cell 30 is located, so as to avoid the laser burning the cell.

[0030] 2) The protrusion 20 can physically block the laser leakage path, thereby blocking the laser energy leakage path;

[0031] 3) Since the above settings can reduce the probability of laser leakage into the mounting cavity 11 and reduce the dispersion of laser beam energy, most of the laser beam is concentrated in the welding area, thus improving the welding yield and reducing rework costs.

[0032] 4) The protrusion 20 can also increase the local rigidity of the housing 10.

[0033] In one embodiment, the housing 10 is made of aluminum.

[0034] In one embodiment, the housing 10 is manufactured using a one-piece molding process.

[0035] In one embodiment of the present invention, the housing assembly further includes a top cover, which is connected to the top surface of the housing 10, and the bottom surface of the top cover has a second preset distance from the protrusion 20.

[0036] In this embodiment, the top cover is directly connected to the top surface of the housing, and there is a second preset distance between the bottom surface of the top cover and the protrusion 20. That is to say, the protrusion 20 does not support the top cover, and the protrusion 20 is only used to block the laser beam that enters the mounting cavity 11 from the gap between the top cover and the top surface of the housing 10 and irradiates the area where the protrusion 20 is located.

[0037] In one embodiment, the second preset distance ranges from 0.2 mm to 0.3 mm.

[0038] See also Figure 2 and Figure 3 As shown, in one embodiment of this utility model, the value range of the first preset distance L1 is 0.05mm≤L1≤0.5mm.

[0039] The above settings can effectively block the laser beam from directly irradiating the inside of the cell 30, ensuring the shielding effect of the protrusion 20, and also reduce the impact of the protrusion 20 on the internal space of the mounting cavity 11.

[0040] See also Figure 2 and Figure 3 As shown, in one embodiment of this utility model, the value range of the first preset distance L1 is 0.1mm≤L1≤0.3mm.

[0041] In this embodiment, the first preset distance L1 is in the range of 0.1mm≤L1≤0.3mm. At this time, the protrusion 20 has a better blocking effect on the laser beam.

[0042] In one embodiment of this utility model, the cross-section of the protrusion 20 is any one of arch, semi-circle, or polygon, and the maximum protrusion height of the protrusion 20 relative to the side wall 12 on which it is located is L2, and the value range of L2 is 0.03mm≤L2≤0.08mm.

[0043] In this embodiment, the value range of L2 is 0.03mm≤L2≤0.08mm, and combined with the value range of the first preset distance L1 being 0.1mm≤L1≤0.3mm, the blocking effect of the protrusion 20 on the laser beam can be guaranteed.

[0044] In one embodiment, L2 is 0.05mm, and the first preset distance L1 is in the range of 0.1mm≤L1≤0.3mm, which makes the protrusion 20 have a better blocking effect on the laser beam. After the battery cell 30 is installed into the mounting cavity 11 and the top cover and the housing 10 are welded together, the battery is subjected to a Hi-Pot test (high voltage insulation test). The Hi-Pot success rate is greater than or equal to 98.5%. The Hi-Pot success rate is the pass rate of the High-Potential high voltage test. The Hi-Pot success rate is equal to the ratio of the number of qualified tests to the total number of tests. The number of qualified tests refers to the number of test samples whose insulation resistance value reaches or exceeds the preset standard under high voltage, while the total number of tests is the total number of test samples.

[0045] See also Figure 2 and Figure 3As shown, in one embodiment of the present invention, there are four side walls 12, and the housing 10 also includes a bottom wall 13. The four side walls 12 are perpendicular to the bottom wall 13 and connected to the bottom wall 13. The four side walls 12 are connected in sequence along the circumference of the bottom wall 13 and together with the bottom wall 13 form an installation cavity 11. The ends of the four side walls 12 away from the bottom wall 13 together form a rectangular opening 14, which communicates with the installation cavity 11. The top of the inner wall surface of the four side walls 12 is provided with a protrusion 20.

[0046] In this embodiment, the battery cell 30 can be inserted into the mounting cavity 11 through the rectangular opening 14. The top of the inner wall surface of the four side walls 12 is provided with protrusions 20, which can greatly improve the blocking rate of the laser beam entering the mounting cavity 11 from the gap between the top cover and the top surface of the housing 10.

[0047] See also Figure 2 and Figure 3 As shown, in one embodiment of this utility model, four protrusions 20 are connected end to end and located on the same horizontal plane.

[0048] In this embodiment, the four protrusions 20 are connected end to end to form a closed ring structure, which can block the laser beam entering the mounting cavity 11 from the gap between the top cover and the top surface of the housing 10 in the circumferential direction, and prevent the laser beam from contacting the battery cell 30 in the mounting cavity 11, thereby preventing the laser beam entering the mounting cavity 11 from burning the battery cell 30, which would lead to problems such as short circuit of the battery cell 30 and electrolyte contamination.

[0049] In one embodiment of the present invention, the outer surface of the protrusion 20 is coated with a coating that is configured to absorb a portion of the laser beam.

[0050] In this embodiment, the coating can absorb the energy of the laser irradiating the protrusion 20, reduce the laser's burning effect on the structure of the protrusion 20, protect the protrusion 20, and extend the service life of the protrusion 20.

[0051] In one embodiment, the coating may be made of carbon-based materials such as carbon black or graphene, and its conductivity may be reduced by specific treatments (such as adding an insulating matrix) to ensure that it does not cause abnormal conductivity inside the battery or form a short circuit path. The coating may also be made of metal oxides such as iron oxide or copper oxide.

[0052] In one embodiment of this utility model, the protrusion 20 and the side wall 12 on which it is located are an integral structure.

[0053] In this embodiment, the protrusion 20 and the side wall 12 are integrally formed, which can ensure the structural strength and rigidity of the shell 10 in the area where the protrusion 20 is located. At the same time, it can also reduce the processing and assembly steps of additional parts in the production process, which is conducive to simplifying the production process and improving production efficiency.

[0054] In one embodiment of this utility model, the protrusion 20 is made of ceramic or aluminum.

[0055] In this embodiment, the protrusion 20 is made of ceramic or aluminum. The protrusion 20 made of the two materials each has its advantages. The protrusion 20 made of ceramic has high heat resistance, while the protrusion 20 made of aluminum has good thermal conductivity and lower material cost.

[0056] Examples and Comparative Examples: Examples include batteries A, B, and C. The casings of batteries A, B, and C are all the casing 10 of this application. After the battery cell is installed into the mounting cavity 11, the top cover and casing 10 are welded together. The comparative example is battery D. Battery D uses the existing casing 40. After the battery cell is installed into the existing casing 40, the top cover and casing 40 are welded together. The Hi-Pot yield after baking is compared between the above examples and comparative examples. Figure 1 The structure of the housing 40 in the prior art is shown.

[0057] The capacity of batteries A, B, C and D is 115Ah. Batteries A, B and C are examples. The difference between the three is the value of the first preset distance L1. See Table 1 for details. The number of batteries A, B, C and D is 20.

[0058] After testing, the corresponding Hi-Pot yield was recorded, and the battery was disassembled to check for burn points. If burn points were found, their size was recorded. The test results are shown in Table 2 below. It should be noted that the size of the burn point area is represented by the number of stars (☆), with more stars indicating a larger burn point area.

[0059] Table 1. Relevant parameters of different batteries

[0060]

[0061] Table 2 Test results for different batteries

[0062] Battery A 98.5％ have ☆☆ Battery B 99.5％ have ☆ Battery C 100％ none / Battery D 97％ have ☆☆☆

[0063] As can be seen from the test results in Table 2, the top of the inner wall surface of at least one side wall 12 of the housing 10 of this application is provided with a protrusion 20, which can effectively prevent the laser from falling into the mounting cavity 11 and significantly improve the Hi-Pot yield.

[0064] According to another aspect of the present invention, a battery is provided, comprising: a battery cell 30; and a housing assembly as described above, wherein the battery cell 30 is mounted within a mounting cavity 11.

[0065] In this embodiment, the battery housing assembly has all the technical features and effects of the aforementioned housing assembly, which will not be repeated here.

[0066] As can be seen from the above description, the above embodiments of this utility model achieve the following technical effects: a housing and a top cover are provided, and a protrusion is provided on the top of the inner wall surface of at least one side wall of the housing. There is a first preset distance between the protrusion and the top surface of the side wall where it is located. The protrusion can block the laser beam that enters the mounting cavity from the gap between the top cover and the top surface of the housing and irradiates the area where the protrusion is located, thus preventing the laser beam that enters the mounting cavity and irradiates the area where the protrusion is located from contacting the battery cell. This can prevent the laser beam that enters the mounting cavity and irradiates the area where the protrusion is located from ablating the battery cell (e.g., burning the electrode, diaphragm, tab or insulating film of the battery cell), which would lead to problems such as short circuit of the battery cell and electrolyte contamination.

[0067] Obviously, the embodiments described above are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0068] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0069] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A housing assembly, characterized in that, include: The housing (10) has a mounting cavity (11). The housing (10) includes at least one side wall (12). A protrusion (20) is provided on the top of the inner wall surface of at least one side wall (12). The protrusion (20) is located in the mounting cavity (11). There is a first preset distance L1 between the protrusion (20) and the top surface of the side wall (12) where it is located.

2. The housing assembly according to claim 1, characterized in that, The housing assembly also includes a top cover, which is connected to the top surface of the housing (10), and the bottom surface of the top cover has a second preset distance from the protrusion (20).

3. The housing assembly according to claim 1, characterized in that, The first preset distance L1 has a value range of 0.05mm≤L1≤0.5mm.

4. The housing assembly according to claim 3, characterized in that, The first preset distance L1 has a value range of 0.1mm≤L1≤0.3mm.

5. The housing assembly according to any one of claims 1 to 4, characterized in that, There are four sidewalls (12), and the housing (10) also includes a bottom wall (13). The four sidewalls (12) are perpendicular to the bottom wall (13) and connected to the bottom wall (13). The four sidewalls (12) are connected sequentially along the circumference of the bottom wall (13) and together with the bottom wall (13) form the mounting cavity (11). The ends of the four sidewalls (12) away from the bottom wall (13) together form a rectangular opening (14). The rectangular opening (14) communicates with the mounting cavity (11). The top of the inner wall surface of the four sidewalls (12) is provided with the protrusion (20).

6. The housing assembly according to claim 5, characterized in that, The four protrusions (20) are connected end to end and located on the same horizontal plane.

7. The housing assembly according to any one of claims 1 to 4, characterized in that, The cross-section of the protrusion (20) is any one of arch, semi-circle, or polygon. The maximum protrusion height of the protrusion (20) relative to the side wall (12) on which it is located is L2, and the value range of L2 is 0.03mm≤L2≤0.08mm.

8. The housing assembly according to any one of claims 1 to 4, characterized in that, The outer surface of the protrusion (20) is coated with a coating that is configured to absorb a portion of the laser beam.

9. The housing assembly according to any one of claims 1 to 4, characterized in that, The protrusion (20) and the sidewall (12) on which it is located are integrally formed; and / or, the protrusion (20) is made of ceramic or aluminum.

10. A battery, characterized in that, include: Battery cell (30); The housing assembly as claimed in any one of claims 1 to 9, wherein the battery cell (30) is mounted within the mounting cavity (11).

Images