Battery

Abstract

The battery comprises a shell and a sealing rubber plug, the shell is provided with a liquid injection hole, and the sealing rubber plug is inserted into the liquid injection hole and seals the liquid injection hole; in the inserting direction of the sealing rubber plug, the radial size of the two ends of the sealing rubber plug is larger than the radial size of the middle of the sealing rubber plug. According to the battery, the structure of the sealing rubber plug of the liquid injection hole is improved, so that the sealing effect of the liquid injection hole can be improved, and the use safety of the battery is guaranteed.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery. Background Technology

[0002] Currently, battery filling holes are mostly sealed using sealing caps and sealing rubber studs. During operation, the sealing rubber stud is first inserted into the filling hole, then the sealing cap is placed over the rubber stud and fixedly connected to the casing with the filling hole. While both sealing caps and rubber studs can provide a certain level of sealing performance, there is no effective method to test the final sealing performance of the filling hole. For example, if the rubber stud provides a seal but the sealing cap fails to seal, the test results may show a valid seal, leading to potential battery safety hazards. Utility Model Content

[0003] The purpose of this application is to provide a battery that improves the sealing effect of the filling hole by modifying the structure of the sealing plug, thereby ensuring the safety of the battery.

[0004] To solve the above-mentioned technical problems, this application provides a battery, the battery including a shell and a sealing plug, the shell having an injection hole, the sealing plug being inserted into the injection hole and sealing the injection hole; along the insertion direction of the sealing plug, the radial dimensions at both ends of the sealing plug are greater than the radial dimension at the middle of the sealing plug.

[0005] The above-described design incorporates a gourd-shaped plug for sealing the electrolyte filling hole, wider at both ends and narrower in the middle. After insertion, the large radial dimensions at both ends prevent the plug from easily detaching, resulting in a superior seal. This is especially effective when the internal battery pressure exceeds the external pressure. While the plug may initially tend to move outwards relative to the battery due to the pressure difference, the large radial dimensions at the ends prevent it from falling out and further enhance the seal. This structural design improves the sealing effect on the electrolyte filling hole, ensuring battery safety. Attached Figure Description

[0006] Figure 1 A structural diagram of the battery provided in one embodiment of this application;

[0007] Figure 2 for Figure 1 The diagram shows the structure of the battery from another perspective;

[0008] Figure 3 This is a partial structural diagram of a battery in one embodiment provided in this application;

[0009] Figure 4 for Figure 3 Partial structural diagram of the middle shell;

[0010] Figure 5 for Figure 3 Structural diagram of the central sealing rubber plug;

[0011] Figure 6 A partial structural diagram of the battery in another embodiment provided in this application;

[0012] Figure 7 for Figure 6 Structural diagram of the central sealing rubber plug;

[0013] Figure 8 A structural diagram of a sealing plug in another embodiment provided in this application.

[0014] Explanation of reference numerals in the attached figures:

[0015] Battery 10, first end 101, second end 102;

[0016] Outer shell 11, outer shell 111, outer shell peripheral wall 1111, outer shell bottom wall 1112, cover 112;

[0017] Injection hole 12;

[0018] Sealing plug 13, first sealing section 131, second sealing section 132, head 133;

[0019] Pressure relief structure 14. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] The ordinal numbers used in this article, such as first and second, are used to distinguish different parts with the same name and do not indicate a specific order or primary / secondary relationship.

[0022] Please refer to Figures 1 to 5 , Figure 1 This is a structural diagram of the battery in one embodiment provided in this application. Figure 2 for Figure 1 The diagram shows the structure of the battery from another perspective. Figure 3 This is a partial structural diagram of the battery in one embodiment provided in this application. Figure 4 for Figure 3 A partial structural diagram of the middle shell. Figure 5 for Figure 3 Structural diagram of the central sealing rubber plug.

[0023] This embodiment provides a battery 10. Without loss of generality, a cylindrical battery is used as an example in the figure. The battery 10 includes a casing 11, and a winding core (not shown in the figure) is disposed inside the casing 11. The casing 11 has an injection hole 12, which is used to inject electrolyte into the casing 11 during the battery manufacturing process to complete the electrochemical performance of the battery. After the electrolyte is injected, the injection hole 12 needs to be sealed.

[0024] The battery 10 also includes a sealing plug 13, which is inserted into and seals the liquid injection hole 12. Along the insertion direction of the sealing plug 13, the radial dimensions at both ends of the sealing plug 13 are larger than the radial dimension in the middle. This can be understood as the sealing plug 13 being gourd-shaped, with larger ends and a smaller middle.

[0025] Using the above scheme, after the sealing plug 13 is inserted into the injection hole 12, due to the large radial dimensions at both ends of the sealing plug 13, it is not easy for the sealing plug 13 to fall out of the injection hole 12, resulting in a good sealing effect on the injection hole 12. Especially when the pressure inside the battery 10 is greater than the external pressure, under the action of the pressure difference, the sealing plug 13 tends to move outward relative to the battery 10. However, because of the large radial dimensions at the ends of the sealing plug 13, it not only will not fall out of the injection hole 12, but it will also form a better sealing performance for the injection hole 12. The structural design of this sealing plug 13 can improve the sealing effect on the injection hole 12, thereby ensuring the safety of the battery 10 in use.

[0026] In application, the sealing plug 13 can be inserted into the injection hole 12 under the action of external force. Since the sealing plug 13 has a certain deformation capacity, under the action of external force, the sealing plug 13 can be deformed to squeeze into the injection hole 12, and then return to its original shape to form a seal on the injection hole 12.

[0027] In some embodiments, the outer casing 11 includes a housing 111 and a cover 112. The housing 111 is generally cylindrical and includes a peripheral wall 1111 and a bottom wall 1112. The top of the housing 111 is open to facilitate the assembly of the battery core 10 and related accessories (such as an insulating film covering the core). The cover 112 is connected to the housing 111 and is used to cover the top opening of the housing 111. The housing 111 and the cover 112 are separate structures.

[0028] In other embodiments, the housing 11 may also be a one-piece structure.

[0029] The cover 112 and the bottom wall 1112 are located at opposite ends of the outer shell 11. The outer shell 11 has opposite first end 101 and second end 102. As shown in the figure, the cover 112 is located at the first end 101 of the outer shell 11, and the bottom wall 1112 is located at the second end 102 of the outer shell 11.

[0030] In some embodiments, the ratio of the maximum radial dimension of the sealing plug 13 to the radial dimension of the injection hole 12 is 1.05 to 1.2, and the radial dimension of the injection hole is 2 mm to 8 mm.

[0031] This design ensures the reliability of the sealant plug 13 in sealing the injection hole 12, and also facilitates the insertion and mating of the sealant plug 13 with the injection hole 12. During assembly, a suitable force can be used to insert the sealant plug 13 into the injection hole 12 without affecting the outer shell 11.

[0032] In applications, the radial dimensions of the injection hole 12 can be 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm or 8mm.

[0033] In applications, the radial dimension of the injection hole 12 can be further limited to the range of 2mm to 5mm, taking into account both the convenience of injection operation and the reliability of subsequent sealing. Specifically, the radial dimension of the injection hole can be 2mm, 2.2mm, 2.6mm, 2.8mm, 3mm, 3.3mm, 3.6mm, 3.8mm, 4mm, 4.4mm, 4.8mm, or 5mm.

[0034] In application, the ratio of the maximum radial dimension of the sealing plug 13 to the radial dimension of the injection hole 12 can be 1.05, 1.07, 1.10, 1.13, 1.16, 1.18 or 1.2.

[0035] In some embodiments, the sealing plug 13 may include a first sealing segment 131 and a second sealing segment 132 connected in sequence. The end of the first sealing segment 131 away from the second sealing segment 132, and the end of the second sealing segment 132 away from the first sealing segment 131, form the two ends of the sealing plug 13 with larger radial dimensions. The junction of the first sealing segment 131 and the second sealing segment 132 is the part of the sealing plug 13 with the smallest radial dimension.

[0036] In some embodiments, the maximum radial dimension d1 of the first sealing segment 131 and the maximum radial dimension of the second sealing segment 132 can be set to the same value. This eliminates the need to consider the orientation of the sealing plug 13 during assembly, thus improving assembly efficiency.

[0037] In the specific implementation, the structures of the first sealing section 131 and the second sealing section 132 are symmetrical.

[0038] In some embodiments, the first sealing section 131 of the sealing plug 13 is the end that is inserted into the injection hole 12, that is, the first sealing section 131 is relatively close to the interior of the outer shell 11, and the radial dimension of the first sealing section 131 increases towards the interior of the outer shell 11, that is, the radial dimension of the first sealing section 131 increases from the second sealing section 132 to the first sealing section 131. In this way, the outer peripheral wall of the first sealing section 131 is a smoothly transitioned wall surface, which is beneficial to the insertion and mating of the sealing plug 13 and the injection hole 12.

[0039] In a specific implementation, the first sealing section 131 of the sealing plug 13 can be frustoconical, and its outer peripheral wall can be conical.

[0040] The structure of the second sealing section 132 of the sealing plug 13 can be similar to that of the first sealing section 131.

[0041] In the scheme where the first sealing section 131 is one end inserted into the injection hole 12, the ratio of the maximum radial dimension d1 of the first sealing section 131 to the minimum radial dimension d2 of the sealing plug 13 can be 1.06~1.3.

[0042] The ratio of the maximum radial dimension d1 of the first sealing section 131 to the minimum radial dimension d2 of the sealing plug 13 should not be too large. If it is too large, it will increase the difficulty of assembling the sealing plug 13 and the injection hole 12. Similarly, the ratio should not be too small. If it is too small, it will not effectively improve the sealing performance of the injection hole 12. Setting the ratio of the maximum radial dimension d1 of the first sealing section 131 to the minimum radial dimension d2 of the sealing plug 13 to 1.06~1.3 balances installation convenience and sealing performance of the injection hole 12.

[0043] In application, the ratio of the maximum radial dimension d1 of the first sealing section 131 to the minimum radial dimension d2 of the sealing plug 13 can be 1.06, 1.08, 1.1, 1.12, 1.14, 1.16, 1.18, 1.2, 1.22, 1.24, 1.26, 1.28 or 1.3.

[0044] In some embodiments, a pressure relief structure 14 is provided on the outer casing 11 of the battery 10, and the liquid injection hole 12 and the pressure relief structure 14 are located on the same shell wall of the outer casing 11. In the illustrated scheme, both the pressure relief structure 14 and the liquid injection hole 12 are located on the bottom wall 1112 of the casing 111.

[0045] The pressure relief structure 14 can be a groove structure formed on the bottom wall 1112 of the casing. In this way, the wall thickness of the bottom wall 1112 of the casing is relatively thin at the location of the pressure relief structure 14. When the battery 10 experiences thermal runaway, after the internal pressure of the battery reaches a certain value, the pressure relief structure 14 can burst open, and the gas accumulated inside the battery can be discharged from the bursting position of the pressure relief structure 14 to ensure the safe use performance of the battery 10.

[0046] In specific implementation, the ratio of the maximum radial dimension d1 of the first sealing section 131 inserted into the outer casing 11 by the sealing plug 13 to the casing wall thickness t at the location of the pressure relief structure 14 is 1.2 to 16. This avoids the assembly of the sealing plug 13 and the injection hole 12 affecting the pressure relief structure 14, ensuring the sealing performance of the injection hole 12 while guaranteeing the reliability of the pressure relief structure 14, thus ensuring the safe operation of the battery 10.

[0047] The shell wall thickness t at the location of the pressure relief structure 14 can be 0.5mm to 1.5mm. In specific applications, the shell wall thickness t at the location of the pressure relief structure 14 can be 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, or 1.5mm.

[0048] In application, the ratio of the maximum radial dimension d1 of the first sealing section 131 inserted into the outer shell 11 of the sealing plug 13 to the shell wall thickness t at the location of the pressure relief structure 14 can be 1.2, 1.3, 1.4, 1.6, 2, 3, 4, 5, 7, 9, 10, 12, 14, 15 or 16.

[0049] In actual installation, the position of the injection hole 12 corresponds to the position of the winding hole of the winding core installed inside the housing 10, and the injection hole 12 is approximately located at the center of the bottom wall 1112 of the housing. In application, the distance L between the injection hole 12 and the pressure relief structure 14 should not be too large to avoid affecting the pressure relief effect of the battery 10 during thermal runaway. Conversely, the distance L should not be too small to avoid adverse effects on the pressure relief structure 14 caused by external forces during the assembly of the sealing plug 13 and the injection hole 12. The distance L between the injection hole 12 and the pressure relief structure 14 can be 8mm to 16mm to balance the pressure relief effect of the pressure relief structure 14 and the assembly reliability of the injection hole 12 and the sealing plug 13.

[0050] In application, the distance L between the injection hole 12 and the pressure relief structure 14 can be 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm or 16mm.

[0051] Figure 3 and Figure 5 In the illustrated design, the sealing plug 13 comprises only two parts: a first sealing section 131 and a second sealing section 132. The structure of the sealing plug 13 can also be other forms. Please refer to [reference needed]. Figure 6 and Figure 7 , Figure 6 A partial structural diagram of the battery in another embodiment provided in this application. Figure 7 for Figure 6 Structural diagram of the central sealing rubber plug.

[0052] exist Figure 6 and Figure 7 In the illustrated embodiment, the injection hole 12 is also provided on the bottom wall 1112 of the housing 111. The sealing plug 13 for sealing the injection hole 12 includes a first sealing section 131 and a second sealing section 132, and also includes a head 133. The first sealing section 131 and the second sealing section 132 are connected, and the second sealing section 132 and the head 133 are connected. The radial dimension of the first sealing section 131 decreases from the first sealing section 131 to the second sealing section 132, and the radial dimension of the second sealing section 132 increases from the first sealing section 131 to the second sealing section 132.

[0053] The first sealing section 131 of the sealing plug 13 is one end that is inserted into the injection hole 12. After the sealing plug 13 is inserted into the injection hole 12, the first sealing section 131 is closer to the inside of the outer shell 11 than the second sealing section 132.

[0054] After the sealing plug 13 is inserted into the injection hole 12, the head 133 can abut against the outer surface of the bottom wall 1112 of the shell to limit the relative position of the sealing plug 13 and the bottom wall 1112 of the shell.

[0055] The maximum radial dimension d1 of the first sealing section 131 can be set to be greater than the maximum radial dimension d2 of the second sealing section 132.

[0056] The radial dimension at the connection between the first sealing section 131 and the second sealing section 132 is the minimum radial dimension d3 of the sealing plug 13. The proportional relationship between the maximum radial dimension d1 and the minimum radial dimension d3 of the first sealing section 131 can be referred to the above. Figures 1 to 5 The description of the illustrated embodiment will not be repeated here. The ratio of the maximum radial dimension d1 of the first sealing section 131 to the shell wall thickness at the pressure relief structure 14 can also be referred to the foregoing. Figures 1 to 5 Description of the illustrated embodiment.

[0057] In the foregoing embodiments, the injection hole 12 is disposed on the bottom wall 1112 of the housing 111, and the ratio of the maximum radial dimension of the sealing plug 13 to the radial dimension of the injection hole 12 is 1.07~1.16, wherein the radial dimension of the injection hole 12 is 2mm~8mm.

[0058] In application, the radial dimension of the injection hole 12 can be set with reference to the above description, and will not be repeated here.

[0059] In application, the ratio of the maximum radial dimension of the sealing plug 13 to the radial dimension of the injection hole 12 can be 1.07, 1.08, 1.09, 1.1, 1.12, 1.13, 1.14, 1.15 or 1.16.

[0060] In other embodiments, the injection hole 12 may also be provided on the cover 112 of the housing 10. In this state, the ratio of the maximum radial dimension of the sealing plug 13 to the radial dimension of the injection hole 12 is 1.1 to 1.3.

[0061] In application, the radial dimension of the injection hole 12 can be set with reference to the above description, and will not be repeated here.

[0062] In application, the ratio of the maximum radial dimension of the sealing plug 13 to the radial dimension of the injection hole 12 can be 1.1, 1.13, 1.16, 1.2, 1.23, 1.27 or 1.3.

[0063] Generally speaking, the thickness of the cover 112 should be greater than the thickness of the bottom wall 1112. When the injection hole 12 is set on the bottom wall 1112, the maximum radial dimension of the sealing plug 13 can be set relatively small.

[0064] In the above embodiments, the outer wall surface of the sealing plug 13 may also be provided with a sealing layer to improve the sealing effect on the injection hole 12.

[0065] In the above embodiments, after the sealing plug 13 is assembled with the injection hole 12, a sealing nail cap that is fixedly connected to the outer shell 11 can be provided on the outer side of the sealing plug 13 away from the outer shell 11. The sealing nail cap covers the part of the sealing plug 13 located in the outer shell 11 to achieve secondary sealing.

[0066] In some embodiments, the injection hole 12 may also be provided with a stepped structure with the stepped surface facing the outside of the housing 11. After the sealing plug 13 is sealed with the injection hole 12, the end of the sealing plug 13 that is not inserted into the injection hole 12 is located at the stepped structure, so that the sealing plug 13 does not protrude from the surface of the housing 11. In the embodiment of providing a sealing cap, the sealing cap is also located at the stepped structure and can be fixedly connected with the stepped surface, so that the sealing cap also does not protrude from the surface of the housing 11.

[0067] In the foregoing embodiments, the radial dimensions of the first sealing segment 131 and the second sealing segment 132 of the sealing plug 13 are progressively increasing or decreasing. In other embodiments, the radial dimensions of the first sealing segment 131 and the second sealing segment 132 of the sealing plug 13 may also vary in other ways, not limited to progressively increasing or decreasing, as can be found in [reference needed]. Figure 8The sealing plug shown is for understanding.

[0068] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A battery, characterized in that, The battery includes a housing and a sealing plug. The housing has an injection hole, and the sealing plug is inserted into the injection hole and seals the injection hole. Along the insertion direction of the sealing plug, the radial dimensions at both ends of the sealing plug are greater than the radial dimension at the middle of the sealing plug.

2. The battery according to claim 1, characterized in that, The sealing plug includes a first sealing section and a second sealing section connected in sequence, wherein the maximum radial dimension of the first sealing section is the same as the maximum radial dimension of the second sealing section.

3. The battery according to claim 1, characterized in that, The ratio of the maximum radial dimension of the sealing plug to the radial dimension of the injection hole is 1.05 to 1.2, and the radial dimension of the injection hole is 2 mm to 8 mm.

4. The battery according to any one of claims 1-3, characterized in that, The sealing plug includes a first sealing section near the interior of the housing, the radial dimension of which increases toward the interior of the housing.

5. The battery according to claim 4, characterized in that, The ratio of the maximum radial dimension of the first sealing section to the minimum radial dimension of the sealing plug is 1.06 to 1.

3.

6. The battery according to any one of claims 1-3, characterized in that, The outer casing is provided with a pressure relief structure, the injection hole and the pressure relief structure are located on the same shell wall of the outer casing, and the sealing plug includes a first sealing section near the inside of the outer casing, the ratio of the maximum radial dimension of the first sealing section to the shell wall thickness of the outer casing at the pressure relief structure is 1.2~16.

7. The battery according to any one of claims 1-3, characterized in that, The outer shell is provided with a pressure relief structure. The injection hole and the pressure relief structure are located on the same shell wall of the outer shell. The distance between the injection hole and the pressure relief structure is 8mm to 16mm.

8. The battery according to any one of claims 1-3, characterized in that, The outer casing includes a shell and a cover. The shell is an open cylindrical structure. The cover seals the open end of the shell. The injection hole is located on the cover. The ratio of the maximum radial dimension of the sealing plug to the radial dimension of the injection hole is 1.1 to 1.

3. The radial dimension of the injection hole is 2 mm to 8 mm.

9. The battery according to any one of claims 1-3, characterized in that, The outer casing includes a shell and a cover. The shell is an open cylindrical structure. The cover seals the open end of the shell. The shell includes a bottom wall opposite to the cover. The injection hole is disposed on the bottom wall. The ratio of the maximum radial dimension of the sealing plug to the radial dimension of the injection hole is 1.07~1.

16. The radial dimension of the injection hole is 2mm~8mm.

10. The battery according to any one of claims 1-3, characterized in that, The battery also includes a sealing cap, which covers the portion of the sealing plug located in the outer casing, and the sealing cap is fixedly connected to the outer casing.

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