Top cover assembly and single battery

Abstract

The utility model is suitable for the technical field of batteries, and discloses a top cover assembly and a single battery. According to the utility model, the top cover assembly comprises a top cover and an anti-explosion sheet, the top cover is provided with a first liquid injection port, and the first liquid injection port is used for allowing electrolyte to pass through; the anti-explosion sheet is connected with the top cover and covers and seals the first liquid injection opening; wherein first matching structures which are matched with each other are arranged at the first position between the top cover and the anti-explosion sheet, and second matching structures which are matched with each other are arranged at the second position between the top cover and the anti-explosion sheet. According to the utility model, the first matching structure and the second matching structure which are used for limiting each other are arranged between the top cover and the explosion-proof sheet, and the first matching structure and the second matching structure can ensure that the explosion-proof sheet is accurately placed at a preset position, so that better connection strength between the explosion-proof sheet and the top cover is ensured. In addition, when the internal pressure of the single battery is too large, the first liquid injection port exhausts air and ejects the anti-explosion sheet, so that the first liquid injection port is reused, punching on the top cover is reduced, and the strength of the top cover is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a top cover assembly and a single cell battery. Background Art

[0002] Currently, new energy battery cells are equipped with a dedicated liquid injection hole for electrolyte and a dedicated vent hole for an explosion-proof sheet (used to discharge internal gas in a timely manner in case of battery abnormalities). The explosion-proof sheet is assembled, welded and sealed on the explosion-proof vent hole of the battery cell top cover assembly before injecting electrolyte into the cell. This will increase the number of openings on the top cover, thereby reducing the strength of the top cover. In addition, the connection strength between the explosion-proof sheet and the top cover is not high. Summary of the Utility Model

[0003] An object of the utility model is to provide a top cover assembly, a single cell battery, etc., which aims to solve the technical problems of the strength of the top cover and the connection strength between the explosion-proof sheet and the top cover.

[0004] To achieve the above object, a solution provided by the utility model is: a top cover assembly, which includes a top cover and an explosion-proof sheet. The top cover is provided with a first liquid injection port for allowing electrolyte to pass through; the explosion-proof sheet is connected to the top cover and seals the first liquid injection port; wherein, a mutually adapted first fitting structure is provided at a first position between the top cover and the explosion-proof sheet, and a mutually adapted second fitting structure is provided at a second position.

[0005] As an implementation manner, the top cover protrudes away from the explosion-proof sheet to form a functional part, the first liquid injection port is opened on the functional part, and an interval space is formed between the functional part and the explosion-proof sheet.

[0006] As an implementation manner, the explosion-proof sheet is provided with a circular notch, and the projection of the first liquid injection port on the explosion-proof sheet falls within the area surrounded by the circular notch.

[0007] As an implementation manner, the first fitting structure includes a rib surrounding the first liquid injection port and a groove provided on the explosion-proof sheet, and the groove and the rib are matched; the second fitting structure includes a first groove on the top cover, the first groove is located on the side of the rib away from the first liquid injection port, and the edge of the explosion-proof sheet is accommodated in the first groove.

[0008] As an implementation manner, the top cover is further provided with a second groove, the second groove is located on the side of the rib close to the first liquid injection port, and at least part of the explosion-proof sheet is accommodated in the second groove.

[0009] As an implementation manner, in the axial direction of the first liquid injection port, the explosion-proof sheet and the bottom of the second groove are spaced apart.

[0010] As an implementation manner, the top cover assembly further includes a protection sheet, a circular boss is formed on the side of the explosion-proof sheet away from the groove, and the protection sheet is attached to the circular boss.

[0011] As an implementation manner, the explosion-proof sheet is provided with a second liquid injection port opposite to the first liquid injection port. The convex strip abuts against the area of the explosion-proof sheet where the second liquid injection port is opened, and an exhaust hole is opened in the area of the top cover facing the explosion-proof sheet. The top cover assembly further includes a sealing member, and the sealing member plugs the second liquid injection port.

[0012] As an implementation manner, the axis of the second liquid injection port coincides with the axis of the first liquid injection port.

[0013] To achieve the above object, another solution provided by the present utility model is: a single cell, which includes a bare battery core, a housing, and the top cover assembly of any one of the above. The bare battery core is placed in the housing, and the top cover assembly is connected to the housing.

[0014] Compared with the prior art, in the present application, the top cover assembly includes a top cover and an explosion-proof sheet. The top cover is provided with a first liquid injection port for allowing the electrolyte to pass through to facilitate the use of the single cell during the liquid injection process. The explosion-proof sheet is connected to the top cover and seals the first liquid injection port. When the internal pressure of the single cell is too high, the explosion-proof sheet is pushed open by exhausting gas through the first liquid injection port, so that the first liquid injection port is reused, and the number of holes punched in the top cover is reduced, thereby improving the strength of the top cover. Among them, a first matching structure and a second matching structure for limiting each other are provided between the top cover and the explosion-proof sheet. The first matching mechanism and the second matching structure can ensure that the explosion-proof sheet is accurately placed at a predetermined position to ensure better connection strength between the explosion-proof sheet and the top cover. In addition, the first matching structure and the second matching structure are provided with a local limiting structure on the top cover, which can strengthen the strength of the top cover and the explosion-proof sheet. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0016] Figure 1 It is a schematic structural diagram of the first embodiment of the top cover assembly provided by the embodiment of the present utility model;

[0017] Figure 2 It is a schematic cross-sectional view of the first embodiment of the top cover assembly provided by the embodiment of the present utility model;

[0018] Figure 3 It is provided by the embodiment of the present utility model Figure 2 Schematic structural diagram of area A in

[0019] Figure 4It is a schematic structural diagram of the second embodiment of the top cover assembly provided by the embodiment of the present utility model;

[0020] Figure 5 It is a schematic cross-sectional view of the second embodiment of the top cover assembly provided by the embodiment of the present utility model;

[0021] Figure 6 It is provided by the embodiment of the present utility model Figure 5 The structural schematic diagram of area B in

[0022] Explanation of the reference numerals in the drawings:

[0023] Top cover 10, first liquid injection port 11, rib 12, first groove 13, second groove 14, functional part 17;

[0024] Spacer 18, exhaust hole 19, explosion-proof film 20, groove 21, annular boss 22, second liquid injection port 24; annular notch 25, limiting part 26, protective film 30, seal 40. Detailed implementation manners

[0025] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0026] It should be noted that all the directional indications (such as up, down, left, right, front, back...) in the embodiments of the present utility model are only used to explain the relative position relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0027] Please refer to Figures 1 to 3 , Figure 1 It is a schematic structural diagram of the first embodiment of the top cover assembly provided by the embodiment of the present utility model, Figure 2 It is a schematic cross-sectional view of the first embodiment of the top cover assembly provided by the embodiment of the present utility model, Figure 3 It is provided by the embodiment of the present utility model Figure 2 The structural schematic diagram of area A in

[0028] In this application, a single battery is protected. The single battery includes a bare battery cell, a housing and a top cover assembly. The bare battery cell is placed in the housing, and the housing also contains electrolyte. The top cover assembly is connected to the housing, and the top cover assembly seals the housing.

[0029] The top cover assembly includes a top cover 10 and a rupture disc 20. The top cover 10 is provided with a first liquid injection port 11 which is used to allow the electrolyte to pass through. The rupture disc 20 is connected to the top cover 10 and seals the first liquid injection port 11. Among them, a first mating structure adapted to each other is provided between the top cover 10 and the rupture disc 20 at a first position, and a second mating structure adapted to each other is provided at a second position. The first mating structure limits the rupture disc 20 at the first position to a predetermined position of the top cover 10, and the second mating structure limits the rupture disc 20 at the second position to a predetermined position of the top cover 10. The rupture disc 20 is mainly used to be pushed open when the pressure in the housing is greater than a preset value, so as to facilitate the pressure discharge in the housing.

[0030] To enable those skilled in the art to have a further understanding of the present application, the applicant will explain the specific assembly method of the single cell:

[0031] 1: Assemble the bare battery cell into the housing;

[0032] 2: Weld the top cover 10 of the top cover assembly and the housing together;

[0033] 3: Inject the electrolyte into the housing through the first liquid injection port 11 on the top cover 10;

[0034] 4: The rupture disc 20 of the top cover assembly and the top cover 10 are adaptively connected through the first mating structure at the first position and the second mating structure at the second position, and are welded and fixed at at least one of them.

[0035] In this embodiment, the top cover assembly includes a top cover 10 and a rupture disc 20. The top cover 10 is provided with a first liquid injection port 11 which is used to allow the electrolyte to pass through to facilitate the use of the single cell during the liquid injection process. The rupture disc 20 is connected to the top cover 10 and seals the first liquid injection port 11. When the internal pressure of the single cell is too high, the rupture disc 20 is pushed open by exhausting gas through the first liquid injection port 11, so as to reuse the first liquid injection port 11 and reduce the punching on the top cover 10. Among them, a first mating structure and a second mating structure for limiting each other are provided between the top cover 10 and the rupture disc 20. The first mating structure limits the rupture disc 20 at the first position to a predetermined position of the top cover 10, and the second mating structure limits the rupture disc 20 at the second position to a predetermined position of the top cover 10. The first mating mechanism and the second mating structure can ensure that the rupture disc 20 is accurately placed at the predetermined position to ensure better connection strength between the rupture disc 20 and the top cover 10. In addition, the first mating structure and the second mating structure are provided with local limiting structures on the top cover 10, which can strengthen the strength of the top cover 10 and the rupture disc 20.

[0036] Further, the explosion-proof sheet 20 is installed and welded on the top cover 10 to cover the first liquid injection port 11, taking into account the sealing of the single battery and saving the cost of the sealing sub-components (sealing aluminum nails, sealing rubber plugs, sealing steel nails, glue, etc.) of the first liquid injection port 11. The explosion-proof sheet 20 is assembled after liquid injection, and the performance of the explosion-proof sheet 20 is not affected during the liquid injection process.

[0037] In one embodiment, the top cover 10 protrudes away from the explosion-proof sheet 20 to form a functional part 17. The functional part 17 extends towards the inside of the housing. The first liquid injection port 11 is opened on the functional part 17, and an interval space 18 is formed between the functional part 17 and the explosion-proof sheet 20. The advantage of the interval space 18 is that it can ensure that the explosion-proof sheet 20 and the functional part 17 do not directly contact. When the pressure in the housing is too high, the pressure can be evenly transmitted to the explosion-proof sheet 20 through the interval space 18, thereby achieving the effect of balancing the pressure. In addition, the explosion-proof sheet 20 will deform and generate internal stress during the installation process, and the interval space 18 can well avoid the deformation of the explosion-proof sheet 20.

[0038] Secondly, the functional part 17 extends towards the inside of the housing, occupying part of the space of the housing. In this way, part of the space of the top cover 10 can be vacated for the explosion-proof sheet 20 to use. The explosion-proof sheet 20 is at least partially accommodated in the top cover 10, so that the single battery can be made shorter in the height direction.

[0039] Further, the explosion-proof sheet 20 is provided with a ring-shaped notch 25, and the projection of the first liquid injection port 11 on the explosion-proof sheet 20 falls into the area surrounded by the ring-shaped notch 25. The ring-shaped notch 25 is the position with the smallest thickness in the explosion-proof sheet 20. When the explosion-proof sheet 20 receives pressure, the explosion-proof sheet 20 preferentially breaks from the ring-shaped notch 25. The first liquid injection port 11 is directly opposite to the area surrounded by the ring-shaped notch 25. Thus, when the pressure in the housing sprays out from the first liquid injection port 11, the force can be directly applied to the area corresponding to the ring-shaped notch 25, and then the ring-shaped notch 25 can be quickly broken.

[0040] In one embodiment, the first matching structure includes a rib 12 surrounding the first liquid injection port 11 and a groove 21 provided on the explosion-proof sheet 20. The groove 21 and the rib 12 cooperate with each other. The rib 12 is provided on the top cover 10, and the groove 21 is provided on the explosion-proof sheet 20. The top cover 10 and the explosion-proof sheet 20 are limited together by the cooperation of the groove 21 and the rib 12 to prevent the explosion-proof sheet 20 from moving relative to the top cover 10.

[0041] The second matching structure includes a first groove 13 on the top cover 10. The first groove 13 is located on the side of the rib 12 away from the first liquid injection port 11. The edge of the explosion-proof sheet 20 is accommodated in the first groove 13. The cooperation between the explosion-proof sheet 20 and the first groove 13 can further prevent the explosion-proof sheet 20 from moving relative to the top cover 10. After the first matching structure and the second matching structure are combined together, the edge of the explosion-proof sheet 20 is welded in the first groove 13 by welding.

[0042] In this embodiment, the first mating structure cooperates through the convex strip 12 and the groove 21 to limit the explosion-proof sheet 20 at a predetermined position on the top cover 10. Then, the second mating structure cooperates through the first groove 13 and the edge of the explosion-proof sheet 20 to further precisely position the contact position between the explosion-proof sheet 20 and the top cover 10, so as to facilitate welding the edge of the explosion-proof sheet 20 to the first groove 13.

[0043] The convex strip 12 can also support the explosion-proof sheet 20, and can limit the circumferential stress deformation of the explosion-proof sheet 20 to protect the explosion-proof performance of the explosion-proof sheet 20 from being affected by stress deformation. The convex strip 12 can also block the liquid overflowing during the liquid injection process to prevent it from flowing to the welding position between the explosion-proof sheet 20 and the top cover 10 and affecting the welding.

[0044] Furthermore, the edge of the explosion-proof sheet 20 does not exceed the first groove 13, and the edge of the explosion-proof sheet 20 is completely accommodated in the first groove 13, so as to ensure the flatness of the contact between the explosion-proof sheet 20 and the top cover 10 and facilitate the implementation of the welding process.

[0045] In another embodiment, the top cover 10 is further provided with a second groove 14. The second groove 14 is located on the side of the convex strip 12 close to the first liquid injection port 11. The first groove 13 and the second groove 14 are located on opposite sides of the convex strip 12. At least part of the explosion-proof sheet 20 is accommodated in the second groove 14. The explosion-proof sheet 20 located in the first groove 13 and the second groove 14 can abut against opposite side surfaces of the convex strip 12, and of course, can also abut against one of the opposite side surfaces of the convex strip 12. In this embodiment, at least part of the explosion-proof sheet 20 is accommodated in the second groove 14 on the top cover 10, so as to let part of the space of the top cover 10 be occupied by the explosion-proof sheet 20. The explosion-proof sheet 20 can reduce the occupation of the external space of the single battery, and thus shorten the height of the single battery.

[0046] Furthermore, in the axial direction of the first liquid injection port 11, the explosion-proof sheet 20 and the second groove 14 are arranged at intervals. The advantage of arranging the explosion-proof sheet 20 and the second groove 14 at intervals is that it can ensure that the explosion-proof sheet 20 and the bottom of the second groove 14 do not directly contact. When the pressure in the housing is too high, the pressure can be evenly transmitted to the explosion-proof sheet 20, so as to achieve the effect of balancing the pressure. In addition, the explosion-proof sheet 20 will deform and generate internal stress during the installation process, which can well avoid the deformation of the explosion-proof sheet 20 from propping up the top cover 10 sheet.

[0047] The top cover assembly further includes a protective sheet 30. An annular boss 22 is formed on the side of the explosion-proof sheet 20 away from the groove 21, and the protective sheet 30 is attached to the annular boss 22. The annular boss 22 is the highest point of the explosion-proof sheet 20. The protective sheet 30 is attached to the annular boss 22 and thus located at the topmost end of the explosion-proof sheet 20. After external pollutants such as dust and water stains move towards the explosion-proof sheet 20, the protective sheet 30 can come into contact with the pollutants first and isolate the pollutants from the explosion-proof sheet 20. Additionally, it has at least the following advantages: 1. The annular boss 22 can enhance the strength and stiffness of the explosion-proof sheet 20 and prevent the explosion-proof sheet 20 from deforming during the assembly process; 2. The annular boss 22 divides the explosion-proof sheet 20 into two inner and outer regions like a dam, and the annular boss 22 can block the heat from spreading from the outside to the inside when the explosion-proof sheet 20 is welded to the top cover 10; 3. Under external strong impacts, the annular boss 22 is the first to be impacted, thus protecting the other positions of the explosion-proof sheet 20 from being impacted.

[0048] Please refer to Figures 4 to 6 , Figure 4 which is a schematic structural diagram of the second embodiment of the top cover assembly provided by the embodiment of the present utility model, Figure 5 which is a schematic cross-sectional diagram of the second embodiment of the top cover assembly provided by the embodiment of the present utility model, Figure 6 which is provided by the embodiment of the present utility model Figure 5 and is a schematic structural diagram of area B in

[0049] The explosion-proof sheet 20 is provided with a second liquid injection port 24 opposite to the first liquid injection port 11. The convex strip 12 abuts against the area of the explosion-proof sheet 20 where the second liquid injection port 24 is opened. An exhaust hole 19 is opened in the area of the top cover 10 opposite to the explosion-proof sheet 20. The top cover assembly further includes a seal 40, and the seal 40 plugs the second liquid injection port 24. The user injects liquid into the first liquid injection port 11 through the second liquid injection port 24. When the pressure in the housing is too high, the pressure is discharged to the explosion-proof sheet 20 through the exhaust hole 19 and the first liquid injection port 11. The explosion-proof sheet 20 can be opened at the annular notch 25 or at the second liquid injection port 24, which is not limited herein.

[0050] In this embodiment, the liquid injection hole of the single cell is on the explosion-proof sheet 20, thereby saving the utilization space on the top cover 10. Additionally, the convex strip 12 supports the area of the explosion-proof sheet 20 where the second liquid injection port 24 is opened. In this way, when injecting liquid into the battery cell, the torque stress of the liquid injection head pressure on the explosion-proof valve can be reduced, and the external force effects such as the collision and pressing of foreign objects on the explosion-proof sheet 20 can also be reduced.

[0051] Further, the axis of the first liquid injection port 11 and the axis of the second liquid injection port 24 can coincide or be approximately coincident. In this way, when injecting liquid through the second liquid injection port 24, the liquid can immediately enter the first liquid injection port 11.

[0052] Further, the first groove 13 can be formed by, for example,Figure 3 a step shown in the figure, or it can also be Figure 6 two steps shown in the figure. Understandably, it can also be other numbers of steps. The more the number of steps, the better the limiting effect.

[0053] Furthermore, the thickness of the explosion-proof sheet 20 within the area surrounded by the annular notch 25 is greater than 0.4 mm to provide sufficient strength and reduce the influence of the pressure inside and outside the area of the annular notch 25 on the annular notch 25.

[0054] It should also be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may be an intermediate element present at the same time. When an element is referred to as "connected to" another element, it can be directly connected to the other element or it can also be indirectly connected to the other element through an intermediate element.

[0055] In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0056] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. All equivalent structural transformations made under the inventive concept of the present invention by using the content of the specification and drawings of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A top cover assembly, characterized in that: include: The top cover (10) is provided with a first liquid injection port (11), wherein the first liquid injection port (11) is used to allow electrolyte to pass through; as well as An explosion-proof disk (20) connected to the top cover (10) and covering the first liquid injection port (11); Wherein, a first matching structure that is mutually compatible is provided at a first position between the top cover (10) and the explosion-proof plate (20), and a second matching structure that is mutually compatible is provided at a second position.

2. The top cover assembly according to claim 1, characterized in that: The top cover (10) protrudes in a direction away from the explosion-proof plate (20) to form a functional portion (17), the first liquid injection port (11) is opened on the functional portion (17), and a spacing space (18) is formed between the functional portion (17) and the explosion-proof plate (20).

3. The top cover assembly according to claim 1, characterized in that: The explosion-proof plate (20) is provided with an annular notch (25), and the projection of the first liquid injection port (11) on the explosion-proof plate (20) falls within the area enclosed by the annular notch (25).

4. The top cover assembly according to any one of claims 1 to 3, characterized in that: The first matching structure comprises a convex strip (12) arranged around the first liquid injection port (11) and a groove (21) arranged on the explosion-proof disk (20), wherein the groove (21) matches the convex strip (12); The second matching structure comprises a first groove (13) on the top cover (10), the first groove (13) being located on a side of the convex strip (12) away from the first liquid injection port (11), and the edge of the explosion-proof plate (20) being accommodated in the first groove (13).

5. The top cover assembly according to claim 4, characterized in that: The top cover (10) is further provided with a second groove (14), the second groove (14) being located on a side of the convex strip (12) close to the first liquid injection port (11), and the explosion-proof disc (20) is at least partially accommodated in the second groove (14).

6. The top cover assembly according to claim 5, characterized in that: In the axial direction of the first liquid injection port (11), the explosion-proof disc (20) and the bottom of the second groove (14) are arranged at a distance.

7. The top cover assembly according to claim 4, characterized in that: The top cover assembly further comprises a protection sheet (30), an annular boss (22) is formed on a side of the explosion-proof sheet (20) away from the groove (21), and the protection sheet (30) is attached to the annular boss (22).

8. The top cover assembly according to claim 4, characterized in that: The explosion-proof plate (20) is provided with a second liquid injection port (24) opposite to the first liquid injection port (11); the convex strip (12) supports the area of ​​the explosion-proof plate (20) provided with the second liquid injection port (24); and the top cover (10) is provided with an exhaust hole (19) in the area facing the explosion-proof plate (20); The top cover assembly also includes a sealing member (40), and the sealing member (40) blocks the second liquid injection port (24).

9. The top cover assembly according to claim 8, characterized in that: The axis of the second liquid injection port (24) coincides with the axis of the first liquid injection port (11).

10. A single cell battery, characterized in that: The single battery comprises a bare cell, a shell and the top cover assembly according to any one of claims 1 to 9, the bare cell is placed in the shell, and the top cover assembly is connected to the shell.

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