Cap assembly and battery

Abstract

A cap assembly and a battery relate to the technical field of battery packaging, and include a connecting piece, the connecting piece includes a sinking platform, the sinking platform is provided with a through hole; an explosion-proof piece, the explosion-proof piece is connected to the sinking platform, the explosion-proof piece is arranged above the through hole of the sinking platform; and a cap, the cap is connected to the connecting piece, and the cap is arranged above the explosion-proof piece. By dividing the explosion-proof piece that bears the current-carrying and pressure-relieving functions in the prior art into a connecting piece for realizing the current-carrying function and an explosion-proof piece for realizing the pressure-relieving function, the squatting sealing process does not cause stress to the explosion-proof piece and the welding point, thereby improving the safety performance of the battery.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packaging, in particular to a cap assembly and a battery. Background Art

[0002] The cap assembly is an important part of the lithium battery packaging process. It is usually located on the top of the battery and seals the electrolyte and internal structure of the battery to prevent the external environment from affecting the battery performance. At the same time, it also provides an electrical connection point so that the battery can be connected to the external circuit and integrates a safety valve or other safety devices to prevent danger when the battery is overcharged or over-discharged.

[0003] In the prior art, the cap assembly includes an explosion-proof disc, which is used to carry current and relieve pressure. The pressure relief function of the explosion-proof disc is generally achieved by setting a scoreline on the explosion-proof disc, which requires that the scoreline position is a weak point. Therefore, during the charging and discharging process, this place will become a hot spot, which is easy to cause safety problems.

[0004] In order to ensure the yield of the battery, it is required to perform a squat sealing process after welding. During the squatting process of the cap, the cap assembly will be displaced relative to the battery roll core, which may easily cause greater stress on the weak point mark position of the explosion-proof plate in the prior art, affecting the consistency of the valve opening pressure value and even affecting the welding strength between the explosion-proof plate and the collecting plate.

[0005] Therefore, it is urgent to develop a cap assembly and a battery to solve the problems in the prior art. Utility Model Content

[0006] The utility model aims to provide a cap assembly and a battery, which splits the existing explosion-proof plate into a connecting plate and an explosion-proof plate, thereby solving the problem in the above-mentioned background technology that large stress is easily generated at the weak point of the explosion-proof plate after squatting and sealing.

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] A cap assembly comprising

[0009] A connecting piece, the connecting piece comprising a sinking platform, and the sinking platform is provided with a through hole;

[0010] An explosion-proof sheet, the explosion-proof sheet is connected to the sinking platform, and the explosion-proof sheet is arranged above the through hole of the sinking platform;

[0011] A cover cap is connected to the connecting piece and is arranged above the explosion-proof piece.

[0012] Furthermore, the cap assembly also includes a sealing ring, and the sealing ring is sleeved outside the connecting piece.

[0013] Furthermore, the connecting piece also includes a bending portion, the bending portion is connected to the sinking platform, the bending portion includes a first portion and a second portion, and the first portion is connected to the second portion.

[0014] Furthermore, the angle between the first portion and the second portion is less than 180°.

[0015] Furthermore, the bent portion surrounds the sinking platform.

[0016] Furthermore, the connecting piece further includes a first connecting portion, and the first connecting portion is connected to the bending portion.

[0017] Furthermore, a bending groove is provided between the first connecting portion and the bending portion.

[0018] Furthermore, the connecting piece further includes a second connecting portion, and the second connecting portion is connected to an outer edge of the first connecting portion.

[0019] A battery comprises a cell assembly, a shell and a cap assembly, wherein the cap assembly is arranged at one end of the shell, the cell assembly is arranged in the shell, and the cap assembly is electrically connected to the cell assembly.

[0020] Furthermore, the sinking platform is connected to the battery core assembly, and a sealing ring is provided between the shell and the connecting piece.

[0021] Compared with the prior art, the beneficial effect of the utility model is that the explosion-proof piece with current-carrying and pressure-relieving functions in the prior art is divided into a connecting piece for realizing the current-carrying function and an explosion-proof piece for realizing the pressure-relieving function, so that the squatting sealing process does not cause stress to the explosion-proof piece, thereby improving the safety performance of the battery.

[0022] At the same time, by arranging a bending portion and a bending groove on the connecting piece, the connecting piece can be deformed in a direction during squatting and sealing, further avoiding the deformation of the sinking platform of the connecting piece caused by squatting and sealing, so as to ensure that the current-carrying and pressure-relief functions of the connecting piece and the explosion-proof piece can be realized normally.

[0023] Other features and advantages of the present invention will be disclosed in detail in the following specific implementations and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the structural explosion of the first embodiment;

[0025] Figure 2 This is a schematic cross-sectional view of the structure of the first embodiment before squatting and sealing;

[0026] Figure 3 This is an enlarged cross-sectional view of the local structure of the first embodiment before squatting and sealing;

[0027] Figure 4 This is an enlarged cross-sectional view of the local structure after squatting and sealing of the first embodiment;

[0028] Figure 5 This is an enlarged cross-sectional view of the local structure of the second embodiment before squatting and sealing;

[0029] Figure 6 This is an enlarged cross-sectional view of the local structure of the second embodiment after squatting and sealing;

[0030] Figure 7 It is a schematic diagram of the overall structure of the third embodiment.

[0031] Explanation of the markings in the figure: 1. connecting piece; 11. sinking platform; 12. bending part; 13. first connecting part; 131. bending groove; 14. second connecting part; 2. explosion-proof piece; 3. cover cap; 4. sealing ring; 5. battery cell assembly; 6. outer shell. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] Cap 3 components, such as Figures 1 to 4 Shown, including

[0035] A connecting piece 1, wherein the connecting piece 1 comprises a sinking platform 11, wherein the sinking platform 11 is provided with a platform through hole, and the sinking platform 11 is used to be electrically connected to the positive electrode current collecting plate of the battery cell assembly 5;

[0036] An explosion-proof plate 2, the explosion-proof plate 2 covers the through hole of the platform and is welded to the sinking platform 11 to seal the through hole on the sinking platform 11;

[0037] A cover cap 3 , which is connected to the connecting piece 1 and is located above the explosion-proof piece 2 , and a through hole is provided on the cover cap 3 .

[0038] In this embodiment, the connection method between the sinking platform 11 and the explosion-proof plate 2 includes welding, and the connection method between the connecting plate 1 and the steel cap also includes welding.

[0039] The present application realizes the current carrying function through the connecting piece 1 and the pressure relief function through the explosion-proof piece 2, so as to avoid deformation of the connecting piece 1 during sealing to affect the pressure relief of the battery. Specifically, the explosion-proof piece 2 may be provided with a pressure relief structure such as a pressure relief score line to realize the pressure relief function, which is a prior art and will not be described in detail in the present application.

[0040] The cap 3 assembly further includes a sealing ring 4 , which is sleeved outside the connecting piece 1 and surrounds the sealing ring 4 .

[0041] Specifically, in this embodiment, Figures 1 to 3 As shown, before squatting and sealing, the connecting piece 1 is as follows from bottom to top:

[0042] The sinking platform 11 is used to connect with the positive electrode current collecting disk. A through hole matching with the positive electrode current collecting disk is arranged in the middle of the sinking platform 11. In this embodiment, the sinking platform 11 is circular.

[0043] The bending portion 12 is connected to the outer side of the sinking platform 11 and surrounds the sinking platform 11; the bending portion 12 and the sinking platform 11 are an integrated structure, the bending portion 12 includes a first portion and a second portion, the first portion is connected to the second portion, the angle between the first portion and the second portion is an acute angle, the bending portion 12 is inwardly concave, and the vertical cross-section of the bending portion 12 is V-shaped or C-shaped, so as to facilitate bending under force, and avoid deformation of the sinking platform 11 caused by the bending portion 12 being subjected to force due to squatting;

[0044] The first connecting portion 13 is connected to the upper part of the bending portion 12 and surrounds the bending portion 12; the first connecting portion 13 and the bending portion 12 are an integral structure, the first connecting portion 13 is annular, and is preferably parallel to the sinking platform 11; the connecting sheet 1 is connected to the cap 3 through the first connecting portion 13, and the first connecting portion 13 and the cap 3 are connected by welding;

[0045] The second connection portion 14 is connected to the outer edge of the first connection portion 13 and surrounds the first connection portion 13. In this embodiment, the second connection portion 14 is vertically arranged to be connected to the upper surface of the cover cap 3 after squatting and sealing to limit the cover cap 3.

[0046] Preferably, a bending groove 131 is provided on the upper surface or the lower surface between the first connecting portion 13 and the bending portion 12, so as to facilitate bending of the connecting portion under force, and further reduce the influence of the connecting portion force on the bending portion 12. Specifically, the bending groove 131 is in the shape of a groove.

[0047] like Figure 4 As shown, after squatting and sealing, the second connecting portion 14 is bent and connected to the upper surface of the cover cap 3.

[0048] Embodiment 2

[0049] like Figures 5 and 6 As shown, the difference between this embodiment and the first embodiment is that the bending portion 12 includes a first portion and a second portion, the first portion is connected to the second portion, and the angle between the first portion and the second portion is an obtuse angle.

[0050] Embodiment 3

[0051] Batteries, such as Figure 7 As shown, it includes a battery cell assembly 5, a shell 6 and the cap 3 assembly, the cap 3 assembly is arranged at one end of the shell 6, the battery cell assembly 5 is arranged in the shell 6, and the cap 3 assembly is electrically connected to the battery cell assembly 5.

[0052] The battery cell assembly 5 includes a battery cell and a positive electrode current collecting plate and a negative electrode current collecting plate connected to the battery cell.

[0053] The sinking platform 11 is welded to the positive current collecting disk, the platform through holes on the sinking platform 11 correspond to the through holes on the positive current collecting disk, and the sealing ring 4 is arranged between the outer shell 6 and the connecting piece 1 to achieve a sealed connection between the outer shell 6 and the connecting piece 1.

[0054] Specifically, the installation process of this application is as follows:

[0055] Put the coil core with positive and negative current collecting discs welded into the steel shell, and after the welding of the negative electrode and the shell is completed, put the sealing ring 4 and the connecting piece 1 on the positive current collecting disc, and weld the sinking platform 11 to the positive current collecting disc; after the liquid injection is completed, weld the explosion-proof disc 2 to the sinking platform 11, and weld the connecting piece 1 to the steel cap; finally, perform squat sealing to form the structure shown. The squat sealing is a prior art and will not be described in detail in this application.

[0056] The utility model provides a cap 3 assembly and a battery, which has a simple structure, is easy to use and has high reliability.

[0057] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0058] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A cap assembly, characterized in that: include A connecting piece, the connecting piece comprising a sinking platform, and the sinking platform is provided with a through hole; An explosion-proof sheet, the explosion-proof sheet is connected to the sinking platform, and the explosion-proof sheet is arranged above the through hole of the sinking platform; A cover cap is connected to the connecting piece and is arranged above the explosion-proof piece.

2. The cap assembly according to claim 1, characterized in that: The cap assembly also includes a sealing ring, which is sleeved outside the connecting piece.

3. The cap assembly according to claim 1, characterized in that: The connecting piece further includes a bending portion, the bending portion is connected to the sinking platform, the bending portion includes a first portion and a second portion, and the first portion is connected to the second portion.

4. The cap assembly according to claim 3, characterized in that: The angle between the first portion and the second portion is less than 180°.

5. The cap assembly according to claim 3, characterized in that: The bent portion surrounds the sinking platform.

6. The cap assembly according to claim 3, characterized in that: The connecting piece further includes a first connecting portion, and the first connecting portion is connected to the bending portion.

7. The cap assembly according to claim 6, characterized in that: A bending groove is provided between the first connecting portion and the bending portion.

8. The cap assembly according to claim 6, characterized in that: The connecting piece further includes a second connecting portion, and the second connecting portion is connected to an outer edge of the first connecting portion.

9. A battery, characterized in that: It comprises a battery cell assembly, a shell and a cap assembly according to any one of claims 1 to 8, wherein the cap assembly is arranged at one end of the shell, the battery cell assembly is arranged in the shell, and the cap assembly is electrically connected to the battery cell assembly.

10. The battery according to claim 9, characterized in that The sinking platform is connected to the battery core assembly, and a sealing ring is arranged between the shell and the connecting piece.

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