Battery and cover assembly structure

Abstract

The application discloses a battery and a cover group structure. The cover group structure comprises a cover plate, a pole and a sealing element. The cover plate is provided with a pole hole, and the cover plate is formed with a first boss. The pole is arranged in the pole hole, and the pole is formed with a second boss. The sealing element is pressed between the pole and the cover plate, the first boss is inserted into the sealing element, and the second boss is inserted into the sealing element. The first boss is at least partially flat, and the second boss is at least partially flat. Compared with the prior art, the flat structure increases the width of the boss, thereby increasing the effective sealing area of the boss. Meanwhile, the flat structure enhances the structural strength of the boss, preventing the boss from being deformed during riveting. The battery adopting the cover group structure significantly enhances the sealing effect and improves the overall reliability.

Description

Technical Field

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

[0002] Traditional battery cover assemblies typically consist of a cover plate, terminals, and seals (such as rubber rings and gaskets). Terminal holes are provided in the cover plate, allowing the terminals to pass through, and seals are placed between the terminals and the cover plate to achieve gas-liquid isolation. However, under conditions such as long-term charge-discharge cycles, thermal expansion and contraction, external vibration and shock, and internal pressure fluctuations, traditional structures are prone to seal failure.

[0003] Existing technologies attempt to improve the seal by thickening the seal, increasing the clamping force, using double seals, or adding adhesives, but these often lead to problems such as increased assembly torque, excessive material stress, limited heat release paths, or inconvenient maintenance and replacement. At the same time, simply increasing the clamping force cannot effectively solve the seal degradation caused by stress distribution and thermal cycling. Utility Model Content

[0004] In view of the shortcomings of the prior art, this application provides a battery and cover assembly structure that can enhance the sealing effect of the seal without significantly increasing assembly complexity and cost.

[0005] To achieve the above objectives, this application adopts the following technical solution: A cover assembly structure includes a cover plate, a pole post, and a sealing element. The cover plate has a pole post hole and a first boss. The pole post passes through the pole post hole and has a second boss. The sealing element is pressed between the pole post and the cover plate. The first boss is inserted into the sealing element, and the second boss is inserted into the sealing element. The first boss is at least partially planar, and the second boss is at least partially planar.

[0006] In one embodiment, along the thickness direction of the cover plate, the first boss includes a first top surface facing the seal, the first top surface abutting against the seal, and the first top surface is at least partially planar; the second boss includes a second top surface facing the seal, the second top surface abutting against the seal, and the second top surface is at least partially planar.

[0007] In one embodiment, the edge of the first top surface is formed with a first rounded corner, and the edge of the second top surface is formed with a second rounded corner.

[0008] In one embodiment, the radii of the first fillet and the second fillet are less than 0.1 mm.

[0009] In one embodiment, the radius of the first rounded corner is R1, the width of the first top surface is L1, and the range of R1 is 1 / 40L1 to 1 / 5L1; the radius of the second rounded corner is R2, the width of the second top surface is L2, and the range of R2 is 1 / 40L2 to 1 / 5L2.

[0010] In one embodiment, the distance between the first boss and the second boss along the radial direction of the pole post is L3, and the bottom radius of the pole post is R3, where L3:R3 = 1 / 5 to 3 / 4.

[0011] In one embodiment, the cover assembly structure includes a pressure ring, and the sealing element includes a first sealing portion, a connecting portion, and a second sealing portion. The first sealing portion and the second sealing portion are respectively connected to opposite ends of the connecting portion. The connecting portion passes through the pole hole. The first sealing portion overlaps the upper surface of the cover plate and presses against the pressure ring and the upper surface of the cover plate. The second sealing portion presses against the lower surface of the pole and the cover plate. The first sealing portion protrudes at least partially toward the pressure ring to form a thickened portion, and the thickness of the first sealing portion in the thickened portion is greater than the thickness of the remaining portions.

[0012] In one embodiment, the height of the first boss is H1, and the width of the first boss is L4, wherein H1 / L4 = 1 / 5 to 5 / 6.

[0013] In one embodiment, the height of the second boss is H2, and the width of the second boss is L5, wherein H2 / L5 = 1 / 6 to 2 / 3.

[0014] This application also provides a battery, including the cover assembly structure and battery body of any of the above embodiments, wherein the battery body is connected to the cover assembly structure.

[0015] The beneficial effects of this application are as follows: This application provides a battery and cover assembly structure. The cover assembly structure includes a cover plate, terminals, and a sealing element. The cover plate has a terminal hole and a first protrusion. The terminal passes through the terminal hole and has a second protrusion. The sealing element is pressed between the terminal and the cover plate. The first protrusion and the second protrusion are inserted into the sealing element. The first protrusion and the second protrusion are at least partially planar. Compared with the prior art, the planar structure increases the width of the protrusion, thereby increasing the effective sealing area of ​​the protrusion. At the same time, the planar structure enhances the structural strength of the protrusion itself, preventing deformation of the protrusion during riveting. The battery using this cover assembly structure significantly strengthens the sealing effect and improves overall reliability. Attached Figure Description

[0016] Figure 1A cross-sectional schematic diagram of a cover assembly structure according to this application is shown; Figure 2 It shows Figure 1 Enlarged view of point A in the image; Figure 3 An exploded view of the components of a cover assembly structure according to this application is shown; Figure 4 Another cross-sectional schematic diagram of a cover assembly structure of this application is shown; Figure 5 It shows Figure 4 Enlarged view of point B in the image; Reference numerals: 1. Cover plate; 11. Pole post hole; 12. First boss; 121. First top surface; 122. First fillet; 13. Third boss; 2. Pole post; 21. Second boss; 211. Second top surface; 212. Second rounded corner; 3. Sealing element; 31. First sealing part; 311. Thickened part; 32. Connecting part; 33. Second sealing part; 4. Pressure ring. Detailed Implementation

[0017] In this application, the terms "set up," "equipped with," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; 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, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0018] The terms “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, 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 application.

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0020] See Figure 1This application provides a battery, including a cover assembly structure and a battery body. The battery body typically includes a casing and an internal core pack, with the core pack housed within the casing. The cover assembly structure is connected to the casing and seals the core pack. The cover assembly structure serves two purposes: sealing the core pack and allowing current to be drawn out externally, ensuring normal battery operation.

[0021] See again Figure 1 The cover assembly structure includes a cover plate 1, an electrode post 2, and a sealing element 3. The cover plate 1 has an electrode post hole 11 and a first boss 12. The electrode post 2 passes through the electrode post hole 11 and has a second boss 21. The sealing element 3 is pressed between the electrode post 2 and the cover plate 1. The first boss 12 is inserted into the sealing element 3, and the second boss 21 is inserted into the sealing element 3.

[0022] In practical applications, the cover plate 1 has a pole hole 11 for the pole 2 to pass through, and a first boss 12 is formed around the pole hole 11 on the cover plate 1. The pole 2 passes through the pole hole 11 axially, and a second boss 21 is provided at the axial position corresponding to the sealing element 3. The sealing element 3 is disposed between the cover plate 1 and the pole 2. During assembly, the first boss 12 can be inserted into the annular cavity or corresponding recess of the sealing element 3 from the axis, and the second boss 21 is similarly inserted into another corresponding part of the sealing element 3, so that the sealing element 3 is pressed together by the cover plate 1 and the pole 2 in the axial direction, and squeezed from the radial direction by the two bosses, so that most of the adhesive in the sealing element 3 is squeezed between the two bosses, forming a locking effect, preventing the adhesive from overflowing, and improving the sealing effect. At the same time, the sealing element 3 forms multiple contact interfaces with the outer wall of the first boss 12, the outer wall of the second boss 21, and the opposite end faces of the pole post 2 and the cover plate 1, thereby forming a multi-segment barrier in the sealing path and further enhancing the sealing effect of the sealing element 3.

[0023] In one embodiment, the first boss 12 is at least partially planar, and the second boss 21 is at least partially planar.

[0024] In practical applications, the first boss 12 of the cover plate 1 has a planar step on its axial end face or radial sidewall that contacts the seal 3, forming a planar pressing surface that matches the seal 3. Correspondingly, the second boss 21 of the pole post 2 also has at least one planar pressing surface at the corresponding position, so that when the seal 3 is pressed between the two bosses, the main contact interface changes from curved surface / rounded corner to plane-to-plane surface contact. Compared with the prior art, the planar structure increases the width of the boss, thereby increasing the effective sealing area of ​​the boss. At the same time, the planar structure enhances the structural strength of the boss itself, preventing deformation of the boss during riveting. The seal 3 can be a sealing ring or an O-ring.

[0025] In one embodiment, the height of the first protrusion 12 is H1, and the width of the first protrusion 12 is L4, where H1 / L4 = 1 / 5 to 5 / 6. In practical applications, this application limits the height and width of the first protrusion 12. If the ratio of the height to the width of the first protrusion 12 is less than 1 / 5, the height of the first protrusion 12 is insufficient, and it cannot effectively restrict the flow of the colloid in the sealant 3. If the ratio of the height to the width of the first protrusion 12 is greater than 5 / 6, the relative width of the first protrusion 12 is insufficient, resulting in an insufficient supporting area below the first protrusion 12 after riveting, which in turn makes the effective contact sealing area of ​​this area insufficient, making it difficult to effectively improve the sealing performance of the battery cell. Therefore, the ratio of the height H1 to the width L4 of the first protrusion 12 is limited to 1 / 5 to 5 / 6, preferably 1 / 3 to 2 / 3, and more preferably 1 / 2, which effectively restricts the outward flow of the sealant 3 during the riveting process and promotes the sealant 3 to more fully fill the micropores or gaps.

[0026] In one embodiment, the height of the second protrusion 21 is H2, and the width of the second protrusion 21 is L5, where H2 / L5 = 1 / 6 to 2 / 3. In practical applications, this application limits the height and width of the second protrusion 21. If the ratio of the height to the width of the second protrusion 21 is less than 1 / 6, the height of the second protrusion 21 is insufficient, and it cannot effectively restrict the flow of the colloid in the sealant 3. If the ratio of the height to the width of the second protrusion 21 is greater than 2 / 3, the relative width of the second protrusion 21 is insufficient, resulting in an insufficient supporting area of ​​the second protrusion 21 after riveting, which in turn makes the effective contact sealing area of ​​this area insufficient, making it difficult to effectively improve the sealing performance of the battery cell. Therefore, the ratio of the height H1 to the width L4 of the second boss 21 is limited to 1 / 6 to 2 / 3, preferably 1 / 3 to 2 / 3, and more preferably 1 / 2, which effectively restricts the outward flow of the seal 3 during the riveting process; it also promotes the seal 3 to fill the micropores or gaps between it and the pole post 2 more fully; the second boss 21 and the first boss 12 cooperate with each other to form a bidirectional constraint on the seal 3, thereby enhancing the sealing effect.

[0027] See Figure 2 Along the thickness direction of the cover plate 1, the first boss 12 includes a first top surface 121 facing the seal 3, the first top surface 121 abuts against the seal 3, and the first top surface 121 is at least partially planar; the second boss 21 includes a second top surface 211 facing the seal 3, the second top surface 211 abuts against the seal 3, and the second top surface 211 is at least partially planar.

[0028] In practical applications, the first boss 12, which is provided along the thickness direction of the cover plate 1, forms a first top surface 121 on the side facing the seal 3. The first top surface 121 is at least partially planar in the area for abutting against the seal 3. Correspondingly, the second boss 21 on the pole post 2 forms a second top surface 211 on the side facing the seal 3. The second top surface 211 is at least partially planar in the area for abutting against the seal 3.

[0029] The first top surface 121 and the second top surface 211, each at least partially planar, form a stable surface contact compression band with the sealing element 3, providing a highly reliable sealing interface. Specifically, the planar top surface increases the effective contact area, making the sealing stress more evenly distributed, thereby extending the sealing life; the radial limiting cooperation of the first boss 12 and the second boss 21 achieves a sealant locking effect, improving the sealing performance.

[0030] See again Figure 2 The edge of the first top surface 121 is formed with a first rounded corner 122, and the edge of the second top surface 211 is formed with a second rounded corner 212.

[0031] In practical applications, a first fillet 122 is provided at the edge of the first top surface 121, and a second fillet 212 is provided at the edge of the second top surface 211. This replaces abrupt transitions with sharp edges or large bevels, ensuring a continuous fillet transition without burrs or sharp peaks, and preventing stress concentration. By forming fillets at the edges of the first top surface 121 and the second top surface 211, the technical problems of assembly scratches, stress concentration, and flanged seals caused by traditional sharp edge contact are solved, achieving more stable assembly introduction and more uniform stress distribution.

[0032] In one embodiment, the radii of the first fillet 122 and the second fillet 212 are less than 0.1 mm. In practical applications, the first fillet 122 and the second fillet 212 can take values ​​such as 0.09 mm, 0.08 mm, 0.07 mm, and 0.06 mm. This application limits the size of the first fillet 122 and the second fillet 212 to maximize the effective plane width of the first top surface 121 and the second top surface 211, and avoids the adverse effects of excessively large fillets on the unit contact pressure and target compression ratio.

[0033] In another embodiment, the radius of the first fillet 122 is R1, the width of the first top surface 121 is L1, and the range of R1 is 1 / 40L1 to 1 / 5L1; the radius of the second fillet 212 is R2, the width of the second top surface 211 is L2, and the range of R2 is 1 / 40L2 to 1 / 5L2.

[0034] In practical applications, this application further limits the dimensions of the edge fillet and the top surface plane through proportional relationships, restricting the size range of the fillet to between 1 / 40 and 1 / 5 of the top surface width. If the fillet is too large, exceeding 1 / 5 of the top surface width, the top surface plane will be narrower, resulting in a smaller sealing contact area and reduced sealing effect. If the fillet is too small, less than 1 / 40 of the top surface width, the small fillet will not be sufficiently sharpened, leading to poor assembly smoothness, increased stress concentration, and a higher risk of scratches. The proportional design of this embodiment maximizes the preservation of the effective sealing area while reducing the risk of stress concentration. R1 can take values ​​such as 1 / 40L1, 1 / 30L1, 1 / 20L1, 1 / 10L1, etc., and R2 can take values ​​such as 1 / 40L2, 1 / 30L2, 1 / 20L2, 1 / 10L2, etc.

[0035] See Figure 3 The cover assembly structure also includes a pressure ring 4, and the sealing element 3 includes a first sealing part 31, a connecting part 32, and a second sealing part 33. The first sealing part 31 and the second sealing part 33 are respectively connected to opposite ends of the connecting part 32. The connecting part 32 passes through the pole hole 11. The first sealing part 31 overlaps the upper surface of the cover plate 1 and presses against the pressure ring 4 and the upper surface of the cover plate 1. The second sealing part 33 presses against the lower surface of the pole 2 and the cover plate 1. The first sealing part 31 at least partially protrudes towards the pressure ring 4 to form a thickened part 311. The thickness of the first sealing part 31 in the thickened part 311 is greater than the thickness of the rest of the part.

[0036] In practical applications, the connecting part 32 of the sealing element 3 is first passed through the pole hole 11. At this time, the first sealing part 31 overlaps the upper surface of the cover plate 1, and the second sealing part 33 abuts against the lower surface of the cover plate 1. Then, the pole 2 is passed through the connecting part 32, and the bottom of the pole 2 abuts against the second sealing part 33. Then, the pressure ring 4 is pressed onto the first sealing part 31. After assembly, the cover assembly structure is riveted. Since the first sealing part 31 has a thickened part 311, during riveting, the pressure ring 4 preferentially squeezes the thickened part 311, squeezing the adhesive of the thickened part 311 outward, making the adhesive between the pressure ring 4 and the sealing element 3 more compact, thus improving the sealing effect between the pressure ring 4 and the sealing element 3. The local protrusion of the thickened part 311 can compensate for the manufacturing tolerances and thermal expansion differences of the cover plate 1, the pressure ring 4 and the pole 2, and reduce local pressure loss caused by component warping or incomplete fitting of the pressure ring 4.

[0037] In one embodiment, the thickened portion 311 is provided in the part of the sealing member 3 near the pole hole 11. In practical applications, the thickened portion 311 is arranged in the part near the pole hole 11, which provides a direct and effective means of suppressing seepage that is most likely to occur at the opening of the pole hole 11: the thickened portion 311 forms a main sealing band with high contact stress in the vicinity of the opening, which preferentially blocks the path of the medium to escape upward along the gap between the outer wall of the pole 2 and the hole wall, thereby reducing the probability of leakage from the root.

[0038] Based on the structure of the aforementioned seal 3, refer again to Figure 3 Along the thickness direction of the cover plate 1, the first boss 12 and the second boss 21 are inserted into the seal 3 from opposite sides of the seal 3 respectively.

[0039] In practical applications, the first boss 12 and the second boss 21 are inserted into the second sealing part 33 from opposite sides, respectively. That is, the second sealing part 33 is clamped between the first boss 12 and the second boss 21. The first boss 12 and the second boss 21 on opposite sides provide radial and axial geometric constraints, suppressing the lateral creep and flanging of the seal 3 under pressure, and improving the sealing durability.

[0040] In one embodiment, the distance between the first protrusion 12 and the second protrusion 21 along the radial direction of the pole post 2 is L3, and the bottom radius of the pole post 2 is R3, where L3:R3 = 1 / 5 to 3 / 4.

[0041] In practical applications, the bottom of the pole post 2 refers to the part where the pole post 2 abuts against the second sealing part 33. A second protrusion 21 is formed at the bottom of the pole post 2. The distance between the first protrusion 12 and the second protrusion 21 has a significant impact on the sealing effect. If the distance between the first protrusion 12 and the second protrusion 21 is too large, the bidirectional sealing effect cannot be achieved; if the distance between the first protrusion 12 and the second protrusion 21 is too small, the adhesive in the sealing element 3 will be easily squeezed and deformed, damaging the sealing element 3. The sealing effect can only be achieved when the distance between the first protrusion 12 and the second protrusion 21 is within an effective range. For example, the distance between the first protrusion 12 and the second protrusion 21 can be 1 / 5, 1 / 4, 1 / 3, or 1 / 2 of the radius of the bottom of the pole post 2.

[0042] Understandably, see Figure 3 and Figure 4 The first protrusion 12 can be located at the edge of the pole hole 11, and the second protrusion 21 can be located further away from the pole hole 11 than the first protrusion 12. Alternatively, the second protrusion 21 can be located at the edge of the pole hole 11, and the first protrusion 12 can be located further away from the pole hole 11 than the second protrusion 21. Both methods can achieve similar technical effects, and this application does not limit them.

[0043] See Figure 5The cover plate 1 can also have a third protrusion 13. Along the thickness direction of the cover plate 1, the third protrusion 13 is inserted into the first sealing part 31, so that the first sealing part 31 is squeezed by the third protrusion 13 in the thickness direction of the cover plate 1. This solves the problem of insufficient guidance of the sealing element 3 and force diffusion in traditional planar pressing, which leads to the main sealing strip being insensitive to sealing, and further improves the sealing performance of the cover assembly structure.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0046] The above description is only a specific embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A cover assembly structure, characterized in that, include: The cover plate has an electrode post hole and a first protrusion. A pole post is inserted through the pole post hole, and the pole post has a second protrusion; A sealing element is pressed between the pole post and the cover plate, the first boss is inserted into the sealing element, and the second boss is inserted into the sealing element; Wherein, the first boss is at least partially planar, and the second boss is at least partially planar.

2. The cover assembly structure according to claim 1, characterized in that, Along the thickness direction of the cover plate, the first boss includes a first top surface facing the seal, the first top surface abutting against the seal, and the first top surface is at least partially planar; the second boss includes a second top surface facing the seal, the second top surface abutting against the seal, and the second top surface is at least partially planar.

3. The cover assembly structure according to claim 2, characterized in that, The edge of the first top surface is formed with a first rounded corner, and the edge of the second top surface is formed with a second rounded corner.

4. The cover assembly structure according to claim 3, characterized in that, The radii of the first fillet and the second fillet are less than 0.1 mm.

5. The cover assembly structure according to claim 3, characterized in that, The radius of the first rounded corner is R1, the width of the first top surface is L1, and the range of R1 is 1 / 40L1 to 1 / 5L1; the radius of the second rounded corner is R2, the width of the second top surface is L2, and the range of R2 is 1 / 40L2 to 1 / 5L2.

6. The cover assembly structure according to claim 1, characterized in that, Along the thickness direction of the cover plate, the first boss and the second boss are inserted into the seal from opposite sides of the seal, respectively.

7. The cover assembly structure according to claim 6, characterized in that, Along the radial direction of the pole post, the distance between the first boss and the second boss is L3, and the bottom radius of the pole post is R3, where L3:R3 = 1 / 5 to 3 / 4.

8. The cover assembly structure according to any one of claims 1 to 7, characterized in that, The cover assembly structure includes a pressure ring, and the sealing element includes a first sealing part, a connecting part, and a second sealing part. The first sealing part and the second sealing part are respectively connected to opposite ends of the connecting part. The connecting part passes through the pole hole. The first sealing part overlaps the upper surface of the cover plate and presses against the pressure ring and the upper surface of the cover plate. The second sealing part presses against the lower surface of the pole and the cover plate. The first sealing portion protrudes at least partially toward the pressure ring to form a thickened portion, wherein the thickness of the first sealing portion in the thickened portion is greater than the thickness of the remaining portions.

9. The cover assembly structure according to any one of claims 1 to 7, characterized in that, The height of the first boss is H1, and the width of the first boss is L4, where H1 / L4 = 1 / 5 to 5 / 6.

10. The cover assembly structure according to any one of claims 1 to 7, characterized in that, The height of the second boss is H2, and the width of the second boss is L5, where H2 / L5 = 1 / 6 to 2 / 3.

11. A battery, characterized in that, It includes the cover assembly structure as described in any one of claims 1 to 10 and the battery body, wherein the battery body is connected to the cover assembly structure.

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