Top cover assembly and cylindrical battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a top cover assembly and a cylindrical battery, the top cover assembly is used for the cylindrical battery, the cylindrical battery comprises a battery cell, the top cover assembly comprises a top cover piece and a sealing nail, a liquid injection hole is formed in the top cover piece, a first step and a second step are arranged in the liquid injection hole, and the sealing nail is arranged in the first step. The second step is arranged on one side, deviating from the battery cell, of the first step; the sealing nail is arranged on the first step; and the end surface of the sealing nail deviating from the battery cell is flush with the end surface of the top cover sheet deviating from the battery cell. Thus, when the second step is formed through stamping, the first step can be extruded, an arc at the first step can be eliminated, a gap between the hole wall of the liquid injection hole and the sealing nail is reduced, the sealing nail can tightly abut against the side wall of the first step, welding of the sealing nail and the top cover piece is facilitated, the welding yield is increased, and the production efficiency is improved. And liquid leakage caused by poor welding is avoided, and the welding effect of the sealing nail and the top cover plate of the cylindrical battery is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a top cap subassembly and cylindrical battery. BACKGROUND

[0002] Battery is a kind of device that can generate current by chemical reaction, and cylindrical battery is a common battery used in various portable devices.

[0003] The cylindrical battery includes a top cover sheet, a shell and an electric core. The electric core is arranged inside the shell, and the top cover sheet is connected with the shell to protect the electric core. In order to inject electrolyte into the shell, a liquid injection hole is usually punched on the top cover sheet.

[0004] After the liquid injection is completed, the sealing nail is assembled into the liquid injection hole to form a closed environment inside the shell. However, due to the mold process during the production of parts, a circular arc transition is formed around the liquid injection hole, which causes a gap between the liquid injection hole wall and the sealing nail, thereby affecting the welding yield, increasing the risk of liquid leakage, and the sealing nail of the cylindrical battery has the problem of poor welding effect with the top cover sheet. SUMMARY

[0005] The utility model aims at providing a top cap subassembly and a cylindrical battery to solve the problem of poor welding effect of the sealing nail of the cylindrical battery with the top cover sheet.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] In a first aspect, a top cap subassembly is used for a cylindrical battery. The cylindrical battery includes an electric core. The top cap subassembly includes a top cover sheet having a liquid injection hole formed therein. A first step and a second step are arranged in the liquid injection hole. The second step is arranged on the side of the first step away from the electric core. A sealing nail is arranged in the first step. The end surface of the sealing nail away from the electric core is flush with the end surface of the top cover sheet away from the electric core.

[0008] Preferably, the side wall of the first step is perpendicular to the end surface of the top cover sheet away from the electric core, and / or the side wall of the second step is perpendicular to the end surface of the top cover sheet away from the electric core.

[0009] Preferably, the width of the first step is greater than the width of the second step.

[0010] Preferably, the depth of the first step is equal to the depth of the second step.

[0011] Preferably, the liquid injection hole is coaxially arranged with the top cover sheet.

[0012] Preferably, the width of the second step is greater than or equal to 1 mm.

[0013] Preferably, the depth of the first step is greater than or equal to 0.15 mm; and / or, the depth of the second step is greater than or equal to 0.15 mm.

[0014] Preferably, the top cover sheet is provided with a guide portion at a position corresponding to the liquid injection hole, and the guide portion is arranged on an end surface of the top cover sheet facing the battery cell.

[0015] Preferably, the length of the guide portion is greater than the depth of the first step.

[0016] In a second aspect, a cylindrical battery includes a battery cell, a housing, and a top cover assembly as described above, the top cover sheet is connected to the housing, and the battery cell is arranged inside the housing.

[0017] The utility model has the advantages of:

[0018] A top cover assembly for a cylindrical battery, the cylindrical battery including a battery cell, the top cover assembly including: a top cover sheet and a sealing nail, the top cover sheet being provided with a liquid injection hole, the liquid injection hole being provided with a first step and a second step, the second step being arranged on a side of the first step away from the battery cell; the sealing nail being arranged on the first step, and an end surface of the sealing nail away from the battery cell being flush with an end surface of the top cover sheet away from the battery cell.

[0019] In this way, by arranging the second step, not only can the circular arc at the first step be eliminated during the forming process, but also when the sealing nail is assembled to the top cover sheet, the side wall of the sealing nail can be in close abutment with the side wall of the first step, the gap between the liquid injection hole wall and the sealing nail is reduced, the sealing nail and the top cover sheet are stably welded, sufficient welding space is reserved for the sealing nail, the welding effect of the sealing nail and the top cover sheet of the cylindrical battery is improved, and liquid leakage caused by poor welding is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a sectional view of the top cover assembly in an embodiment of the utility model;

[0021] Figure 2 is an enlarged view of A in the top cover assembly in an embodiment of the utility model; Figure 1

[0022] Figure 3 is a top view of the top cover assembly in an embodiment of the utility model;

[0023] Figure 4 is a structural schematic view of the top cover assembly in an embodiment of the utility model.

[0024] In the drawings:

[0025] ​1. Top cover plate; 11. Injection hole; 111. First step; 112. Second step; 12. Guide part; 2. Sealing nail; 3. Explosion-proof plate. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0027] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0028] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0030] See Figures 1 to 4The utility model provides a top cover assembly for cylindrical battery, cylindrical battery includes electric core, and the top cover assembly includes top cover sheet 1 and sealing nail 2, top cover sheet 1 is set up with liquid injection hole 11, first step 111 and second step 112 are provided in liquid injection hole 11, and second step 112 is set up at the side of first step 111 away from electric core, sealing nail 2 is set up at first step 111, and the end face of sealing nail 2 away from electric core is flush with the end face of top cover sheet 1 away from electric core.

[0031] In the embodiment, the top cover sheet 1 is arranged above the electric core, and the top cover sheet 1 and the sealing nail 2 are both circular plate structures, the liquid injection hole 11 is a through hole penetrating the top surface (i.e., the end surface away from the electric core) and the bottom surface (i.e., the end surface facing the electric core) of the top cover sheet 1, so that the electrolyte can be transported through the liquid injection hole 11 along the direction from the top surface to the bottom surface of the top cover sheet 1, the second step 112 and the first step 111 are sequentially arranged, the second step 112 is formed in the liquid injection hole 11 by stamping, the sealing nail 2 is fixedly connected with the top cover sheet 1 by welding, the side wall of the sealing nail 2 abuts against the side wall of the first step 111, and the welding area of the sealing nail 2 is arranged at the edge of the side wall of the sealing nail 2; the diameter of the end of the liquid injection hole 11 away from the electric core (i.e., the end where the second step 112 is arranged) is 14 mm.

[0032] In this way, the second step 112 is formed by stamping, which can eliminate the circular arc at the first step 111, when the sealing nail 2 is assembled, the sealing nail 2 can tightly abut against the side wall of the first step 111, the gap between the hole wall of the liquid injection hole 11 and the sealing nail 2 is reduced, the sealing nail 2 can be stably welded with the top cover sheet 1, the welding yield is improved, liquid leakage caused by poor welding is avoided, the welding effect of the sealing nail 2 and the top cover sheet 1 of the cylindrical battery is improved, and the arrangement of the first step 111 and the second step 112 can facilitate the flow of the electrolyte along the direction of the second step 112 and the first step 111, reduce the electrolyte remaining in the liquid injection hole 11, and be beneficial to the welding of the sealing nail 2 and the top cover sheet 1.

[0033] It can be understood that the top cover assembly can also be used for square batteries, which will not be enumerated here; the diameter of the liquid injection hole 11 can be adjusted according to actual design needs, which will not be described here.

[0034] Referring to Figure 2 In some embodiments, the side walls of the first step 111 and the second step 112 are both perpendicular to the end surface of the top cover sheet 1 away from the electric core, i.e., the side walls of the first step 111 and the second step 112 are both vertically arranged. In the embodiment, the first step 111 and the second step 112 are coaxially arranged.

[0035] Therefore, the sidewall of the first step 111 and the sidewall of the second step 112 are vertically arranged, which facilitates the stamping of the first step 111 and the second step 112 in the liquid injection hole 11, and makes the sealing nail 2 overlap the first step 111 and limits the position of the sealing nail 2 in the liquid injection hole 11, avoids the shaking of the sealing nail 2 in the liquid injection hole 11, makes the sealing nail 2 more closely cooperate with the liquid injection hole 11, improves the sealing performance of the top cover sheet 1, and reduces the requirement for the size accuracy of the liquid injection hole 11 and the sealing nail 2, so that the first step 111 can provide a fault-tolerant space, and facilitate the assembly of the sealing nail 2.

[0036] It can be understood that the angle between the sidewall of the first step 111 and the end surface of the top cover sheet 1 away from the battery cell can be adjusted according to the slope of the sidewall of the sealing nail 2, and the sidewall of the sealing nail 2 can be abutted with the sidewall of the first step 111, which will not be described here.

[0037] Referring to Figure 1 and Figure 2 In some embodiments, the width of the first step 111 is greater than the width of the second step 112.

[0038] In this embodiment, the length of the first step 111 extending along the horizontal direction (i.e., the length direction of the top cover sheet 1) is the width of the first step 111, the length of the second step 112 extending along the horizontal direction is the width of the second step 112, and the width of the first step 111 is less than the diameter of the sealing nail 2.

[0039] Therefore, the first step 111 has a larger width, which can increase the contact area with the sealing nail 2, thereby stably supporting the sealing nail 2. When the sealing nail 2 is welded, the second step 112 can provide a welding space, avoid the end surface of the top cover sheet 1 being uneven, and improve the surface flatness of the top cover sheet 1 and the welding yield of the sealing nail 2 and the top cover sheet 1.

[0040] It can be understood that the width of the first step 111 and the width of the second step 112 can be adjusted according to actual needs, which can realize that the sealing nail 2 is stably overlapped on the first step 111, and the second step 112 has sufficient welding space, which will not be described here.

[0041] Referring to Figure 2 In some embodiments, the depth of the first step 111 is equal to the depth of the second step 112.

[0042] Therefore, by arranging the first step 111 and the second step 112 with the same depth, not only the processing is facilitated, but also the staff can assemble the sealing nail 2 to the first step 111 and limit the position of the sealing nail 2 on the top cover sheet 1, avoid the sealing nail 2 from being offset due to the gap with the liquid injection hole 11, and improve the welding yield and the welding effect of the sealing nail 2 and the top cover sheet 1 of the cylindrical battery.

[0043] It can be understood that the depth of the first step 111 can also be greater than or less than the depth of the second step 112. In the embodiment, the depth of the first step 111 is equal to the depth of the second step 112, which is to facilitate processing and assembly.

[0044] Referring to Figure 3 In some embodiments, the liquid injection hole 11 is coaxially arranged with the top cover sheet 1.

[0045] In the embodiment, when the sealing nail 2 is clamped in the first step 111, the sealing nail 2 is coaxially arranged with the first step 111.

[0046] In this way, the liquid injection hole 11 coaxially arranged on the top cover sheet 1 can make the electrolyte flow more directly into the battery interior, reduce the resistance and loss of the electrolyte during the injection process, improve the injection efficiency, and facilitate the uniform diffusion of the electrolyte in the battery cell, thereby avoiding uneven distribution of the electrolyte. The coaxial arrangement of the sealing nail 2 and the first step 111 can uniformly weld the edge of the sealing nail 2 with the top cover sheet 1, stably connect the sealing nail 2 with the top cover sheet 1, and improve the sealing performance of the sealing nail 2.

[0047] It can be understood that the position of the liquid injection hole 11 can be adjusted according to the size of the top cover sheet 1, which will not be described here.

[0048] Referring to Figure 1 and Figure 2 In some embodiments, the width of the second step 112 is greater than or equal to 1 mm. For example, the width of the second step 112 can be 1 mm, 1.5 mm, 2 mm, or 2.5 mm.

[0049] In this way, the second step 112 can reserve space for welding of the sealing nail 2 and the top cover sheet 1, so that the sealing nail 2 can be stably welded with the top cover sheet 1, thereby making the surface of the top cover sheet 1 more flat, improving the welding yield, reducing the risk of liquid leakage, and improving the welding effect of the sealing nail 2 and the top cover sheet 1 of the cylindrical battery.

[0050] It can be understood that the width of the second step 112 can be flexibly adjusted according to the specifications of the sealing nail 2 and the top cover sheet 1. The width of the second step 112 is greater than or equal to 1 mm, which is to extrude the first step 111 and deform the circular arc edge into a vertical side wall when processing the second step 112, so that the side wall of the first step 111 tightly abuts against the side wall of the sealing nail 2, reduces the gap between the sealing nail 2 and the top cover sheet 1, and improves the welding effect.

[0051] Referring to Figure 1 In some embodiments, the depth of the first step 111 is greater than or equal to 0.15 mm, and the depth of the second step 112 is greater than or equal to 0.15 mm.

[0052] Exemplarily, the depth of the first step 111 can be 0.15 mm, 0.18 mm, 0.2 mm, 0.22 mm, or 0.25 mm, the depth of the second step 112 can be 0.15 mm, 0.18 mm, 0.2 mm, 0.22 mm, or 0.25 mm, and the thickness of the sealing spike 2 is equal to the sum of the depth of the first step 111 and the depth of the second step 112, so that when the sealing spike 2 abuts against the first step 111, the end face of the sealing spike 2 away from the battery cell is flush with the end face of the top cover sheet 1 away from the battery cell.

[0053] In this way, when the sealing spike 2 is arranged in the first step 111, the end face of the sealing spike 2 away from the battery cell protrudes from the first step 111, so as to facilitate welding of the sealing spike 2 and the top cover sheet 1, and realize sealed connection of the sealing spike 2 and the top cover sheet 1.

[0054] It can be understood that the depth of the first step 111 and the depth of the second step 112 can be adjusted according to the thickness of the sealing spike 2, which will not be described herein.

[0055] Referring to Figure 1 In some embodiments, the top cover sheet 1 is provided with a guide portion 12 at a position corresponding to the liquid injection hole 11, and the guide portion 12 is arranged at the end face of the top cover sheet 1 facing the battery cell.

[0056] In this embodiment, the length direction of the guide portion 12 is parallel to the thickness direction of the top cover sheet 1, and the guide portion 12 is integrally formed with the top cover sheet 1, and the guide portion 12 and the first step 111 are smoothly connected. When the sealing spike 2 is arranged in the first step 111, the sealing spike 2 is coaxial with the guide portion 12.

[0057] In this way, the guide portion 12 can guide the flow of electrolyte, so that the electrolyte can fully contact the battery cell. After the sealing spike 2 is assembled to the top cover sheet 1, the end of the guide portion 12 away from the battery cell can be covered, and the liquid injection hole 11 is sealed.

[0058] It can be understood that the arrangement position of the guide portion 12 can be adjusted according to design needs, as long as the electrolyte can flow along the guide portion 12, which will not be described herein.

[0059] Referring to Figure 1 In some embodiments, the length of the guide portion 12 is greater than the depth of the first step 111.

[0060] In this embodiment, the length of the guide portion 12 is greater than the depth of the second step 112, and the diameter of the end of the liquid injection hole 11 facing the battery cell (i.e., the end where the guide portion 12 is arranged) is smaller than the diameter of the end of the liquid injection hole 11 away from the battery cell.

[0061] Therefore, the guide portion 12 has a longer depth, the position of the top cover sheet 1 where the liquid injection hole 11 is formed has higher structural strength, the sealing nail 2 supports the top cover sheet 1, and the sealing nail 2 can be kept stable during welding.

[0062] It can be understood that the end of the sealing nail 2 towards the guide portion 12 can also extend downwardly and be embedded in the guide portion 12, so as to further improve the sealing performance of the sealing nail 2.

[0063] Referring to Figure 1 The utility model also provides a cylindrical battery, including electric core, shell (not shown in the drawing) and top cover assembly, top cover sheet 1 is connected with shell, and electric core is arranged in the shell inside.

[0064] In the embodiment, the top cover sheet 1 is fixedly connected with the shell and forms a cylindrical accommodating space, the electric core is arranged in the accommodating space, and the guide portion 12 is coaxially arranged with the electric core.

[0065] Therefore, the sealing nail 2 is welded on the top cover sheet 1, can seal the accommodating space after the electrolyte is injected into the shell, so as to avoid the leakage of the electrolyte to the outside, ensure the safety of the cylindrical battery, the sealing nail 2 is clamped in the first step 111, can limit the position of the sealing nail 2, make the sealing nail 2 can be stably arranged on the top cover sheet 1, improve the sealing performance of the sealing nail 2.

[0066] Further, the top cover assembly further comprises an explosion-proof sheet 3, and the explosion-proof sheet 3 is concentrically arranged with the liquid injection hole 11.

[0067] Obviously, the above embodiment of the utility model is only for clear illustration of the utility model, and is not limited to the embodiment of the utility model. For ordinary skilled person in the art, various obvious changes, re-adjustment and replacement can be made without departing from the protection scope of the utility model. Here, it is unnecessary and impossible to enumerate all the embodiments. Any modification, equivalent replacement and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model claim.

Claims

1. A top cover assembly for a cylindrical battery, the cylindrical battery comprising a cell, characterized in that, The top cover assembly includes: Top cover plate (1), the top cover plate (1) is provided with a liquid injection hole (11), the liquid injection hole (11) is provided with a first step (111) and a second step (112), the second step (112) is provided on the side of the first step (111) away from the battery cell; A sealing pin (2) is disposed on the first step (111), and the end face of the sealing pin (2) facing away from the battery cell is flush with the end face of the top cover plate (1) facing away from the battery cell.

2. The top cover assembly according to claim 1, characterized in that, The sidewall of the first step (111) is perpendicular to the end face of the top cover (1) away from the end face of the battery cell; and / or, the sidewall of the second step (112) is perpendicular to the end face of the top cover (1) away from the end face of the battery cell.

3. The top cover assembly according to claim 1, characterized in that, The width of the first step (111) is greater than the width of the second step (112).

4. The top cover assembly according to claim 1, characterized in that, The depth of the first step (111) is equal to the depth of the second step (112).

5. The top cover assembly according to claim 1, characterized in that, The injection hole (11) is coaxially arranged with the top cover plate (1).

6. The top cover assembly according to any one of claims 1-5, characterized in that, The width of the second step (112) is greater than or equal to 1 mm.

7. The top cover assembly according to any one of claims 1-5, characterized in that, The depth of the first step (111) is greater than or equal to 0.15 mm; and / or the depth of the second step (112) is greater than or equal to 0.15 mm.

8. The top cover assembly according to any one of claims 1-5, characterized in that, The top cover plate (1) is provided with a guide portion (12) corresponding to the position of the liquid injection hole (11), and the guide portion (12) is provided on the end face of the top cover plate (1) facing the battery cell.

9. The top cover assembly according to claim 8, characterized in that, The length of the guide portion (12) is greater than the depth of the first step (111).

10. A cylindrical battery, characterized in that, It includes a battery cell, a housing, and a top cover assembly as described in any one of claims 1-9, wherein the top cover sheet (1) is connected to the housing, and the battery cell is disposed inside the housing.

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