Battery top cover assembly and single battery

Abstract

The invention discloses a battery top cover assembly and a single battery, wherein the battery top cover assembly comprises a top cover and an explosion-proof valve, wherein the top cover is provided with an explosion-proof hole, and the top cover is used to seal a housing; the explosion-proof valve comprises a reinforcing boss and an explosion-proof sheet, wherein the reinforcing boss is arranged around the explosion-proof sheet, the thickness of the reinforcing boss is greater than that of the explosion-proof sheet, the reinforcing boss is connected to the top cover, and the explosion-proof sheet seals the explosion-proof hole. The battery top cover assembly of the invention increases the anti-deformation capability of the explosion-proof valve, can effectively reduce the influence of the top cover deformation on the explosion-proof valve, and improve the reliability of the explosion-proof valve.

Description

Technical Field

[0001] The present invention relates to the technical field of battery top cover components, and in particular to a battery top cover component and a single battery. Background Art

[0002] The outer shell, top cover and matching seals of the power battery together form a closed space, which contains components such as the core, electrolyte, active substances, insulating film and various substances required for electrochemical energy conversion. The battery cell will slowly produce gas during normal use, and will produce gas violently under some abuse conditions (such as internal short circuit), causing the air pressure in the closed space of the battery cell to continue to rise. The pressure resistance limit of the connection between the shell and the top cover is limited. If the internal pressure continues to rise and exceeds the pressure resistance limit of the shell and the top cover, it will cause the power battery to explode, posing a safety risk. Therefore, it is necessary to design a safe and reliable explosion-proof valve, which will be opened by the internal air pressure under set conditions to release the internal gas and avoid the explosion of the power battery.

[0003] The currently commonly used explosion-proof valve structure is to process and thin the middle area of ​​a flat substrate. The main problem with this method is that the explosion-proof valve has poor resistance to mechanical tension and pressure performance, and the explosion-proof pressure of the explosion-proof valve is unstable, which affects the life and safety and reliability of the power battery. Summary of the invention

[0004] The purpose of the present invention is to provide a battery top cover assembly and a single cell to solve the technical problem of poor explosion-proof capability of the single cell.

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical solutions: a battery top cover assembly is provided, the battery top cover assembly comprises:

[0006] A top cover is provided with an explosion-proof hole and is used to seal the shell;

[0007] The explosion-proof valve comprises a reinforcing boss and an explosion-proof disc. The reinforcing boss is arranged around the explosion-proof disc. The thickness of the reinforcing boss is greater than that of the explosion-proof disc. The reinforcing boss is connected to the top cover. The explosion-proof disc covers the explosion-proof hole.

[0008] Optionally, the reinforcing boss is welded to the top cover.

[0009] Optionally, a limit groove is provided around the explosion-proof hole on the top cover, and the reinforcing boss is limitedly assembled in the limit groove.

[0010] Optionally, the reinforcing boss includes a first convex portion and a second convex portion, the first convex portion is arranged around the explosion-proof plate, the first convex portion is limitedly assembled in the limiting groove, and the first convex portion is flush with the top cover, and the second convex portion is stacked on the first convex portion.

[0011] Optionally, the thickness of the first protrusion is greater than the thickness of the burst disk.

[0012] Optionally, the reinforcing boss further includes a third convex portion, the third convex portion is arranged around the second convex portion and is connected to the explosion-proof plate, and the third convex portion is sunken relative to the second convex portion to form a step structure.

[0013] Optionally, the top cover is provided with a chamfer at the edge of the limiting groove.

[0014] Optionally, the battery cover assembly further includes a protective sheet, which is attached to the reinforcing boss to cover the explosion-proof sheet.

[0015] Optionally, the thickness of the bursting disk is 0.4 mm to 1 mm, and the bursting disk is provided with notches.

[0016] To achieve the above object, the present invention adopts the following technical solution: a single battery is provided, which includes: a battery cell, a shell and the above-mentioned battery top cover assembly, the battery cell is assembled in the shell, and the battery top cover assembly covers the shell.

[0017] The beneficial effects of the embodiments of the present invention are as follows: the battery top cover assembly of the present application includes a top cover and an explosion-proof valve, and the explosion-proof valve is connected to the top cover as an independent component.

[0018] The top cover covers the shell body and is provided with an explosion-proof hole, which allows gas to flow out.

[0019] The explosion-proof valve includes a reinforced boss and an explosion-proof disk. The reinforced boss is arranged around the explosion-proof disk, the reinforced boss is annular, the reinforced boss is connected to the top cover, and the explosion-proof disk covers the explosion-proof hole. When the pressure in the shell reaches the limit, the gas in the shell breaks through the explosion-proof disk and is discharged to prevent the explosion of the single battery. The thickness of the reinforced boss is greater than that of the explosion-proof disk, wherein the reinforced boss is used to improve the performance of the explosion-proof disk against external mechanical force pulling and squeezing, thereby protecting the explosion-proof disk from external forces. The explosion-proof disk maintains the stability of the bursting pressure, ensuring that the explosion-proof disk will not open prematurely and shorten the life of the single battery, and can also avoid the safety hazards caused by abnormal explosion pressure of the explosion-proof disk. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments or early research and development of the present invention, the drawings required for use in the embodiments or early research and development descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the assembly structure of a single cell provided in this application;

[0022] Figure 2 It is a schematic diagram of the assembly structure of the battery top cover assembly provided by the present application;

[0023] Figure 3 It is a schematic diagram of the exploded structure of the battery top cover assembly provided by the present application;

[0024] Figure 4 It is a schematic diagram of the top view of the explosion-proof valve provided by the present application;

[0025] Figure 5 This application provides Figure 4 A schematic cross-sectional view of an embodiment along the III-III direction;

[0026] Figure 6 This application provides Figure 4 A schematic cross-sectional view of another embodiment along direction III-III.

[0027] The graphic markings are as follows:

[0028] Single battery 100 Battery cell housing 20 Battery top cover assembly 10 Top cover 12

[0029] Explosion-proof hole 121 Limiting groove 123 Chamfer 125 Explosion-proof valve 14

[0030] Reinforced boss 141 Explosion-proof disk 142 First convex portion 143 Second convex portion 144

[0031] Third protrusion 145 protection sheet 16 DETAILED DESCRIPTION

[0032] 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 indicating the number of the indicated technical features.

[0033] See also Figure 1 , Figure 1 It is a schematic diagram of the assembly structure of the single cell 100 provided in the present application.

[0034] The single cell 100 of the present application includes: a battery cell ( Figure 1 The battery cell is an energy storage component, the battery cell is assembled in the shell 20, the battery top cover assembly 10 covers the shell 20, and the battery top cover 12 is electrically connected to the battery cell to assist in introducing electrical energy into the battery cell and extracting energy from the battery cell.

[0035] See also Figures 1 to 5 , Figure 2 is a schematic diagram of the assembly structure of the battery top cover assembly 10 provided in this application, Figure 3 is a schematic diagram of the exploded structure of the battery top cover assembly 10 provided in this application, Figure 4 1 is a schematic diagram of the top view of the explosion-proof valve 14 provided in the present application. Figure 5 This application provides Figure 4 A schematic cross-sectional view of an embodiment along the III-III direction.

[0036] The battery top cover assembly 10 of the present application includes a top cover 12 and an explosion-proof valve 14 , and the explosion-proof valve 14 is connected to the top cover 12 as an independent component.

[0037] The top cover 12 covers the housing 20 and is provided with an explosion-proof hole 121 , which allows gas to flow out.

[0038] The explosion-proof valve 14 includes a reinforcing boss 141 and an explosion-proof disc 142. The reinforcing boss 141 is arranged around the explosion-proof disc 142, and the reinforcing boss 141 is annular. The reinforcing boss 141 is connected to the top cover 12, and the explosion-proof disc 142 covers the explosion-proof hole 121. When the pressure in the shell 20 reaches the limit, the gas in the shell 20 breaks through the explosion-proof disc 142 and is discharged to prevent the single battery 100 from exploding. The thickness of the reinforcing boss 141 is greater than that of the explosion-proof disc 142, wherein the reinforcing boss 141 is used to improve the performance of the explosion-proof disc 142 in resisting external mechanical force pulling and squeezing, thereby protecting the explosion-proof disc 142 from external force. The explosion-proof disc 142 maintains the stability of the explosion pressure, ensuring that the explosion-proof disc 142 will not be opened prematurely to shorten the life of the single battery 100, and can also avoid the safety hazards caused by abnormal explosion pressure of the explosion-proof disc 142.

[0039] The thickness of the explosion-proof sheet 142 is 0.4 mm to 1 mm, for example, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc. The thickness of the explosion-proof sheet 142 affects the maximum pressure that it can withstand. The thicker the explosion-proof sheet 142 is, the greater the maximum pressure that it can withstand. Therefore, the thickness of the explosion-proof sheet 142 is determined by the maximum pressure warned by the single battery 100. The explosion-proof sheet 142 is provided with notches, which are conducive to the explosion of the explosion-proof sheet 142. The notches are opened under the set air pressure specifications to form a pressure relief channel for the explosion-proof hole 121. The shape of the notches can be wavy, triangular, circular, arc-shaped, etc. The notches can be carved on either side of the explosion-proof sheet 142.

[0040] The reinforcing boss 141 is welded to the top cover 12, preferably by laser welding, but of course welding by carbon dioxide shielded welding and other methods is not excluded. In this solution, the reinforcing boss 141 structure can absorb a part of the heat conducted by welding when the explosion-proof valve 14 is welded to the top cover 12, and when the top cover 12 is welded to the shell 20, thereby reducing the influence of this uncertain heat on the explosion-proof disk 142, so as to improve the stability of the bursting pressure of the explosion-proof disk 142. Of course, the reinforcing boss 141 and the top cover 12 can also be connected by screws.

[0041] The top cover 12 is provided with a limiting groove 123 around the explosion-proof hole 121 , and the reinforcing boss 141 is limitedly assembled in the limiting groove 123 to prevent the explosion-proof valve 14 from moving during welding.

[0042] The top cover 12 is provided with a chamfer 125 at the edge of the limiting groove 123 . The chamfer 125 may be a beveled angle or a rounded angle, so as to guide the explosion-proof valve 14 to be installed in the limiting groove 123 .

[0043] The reinforcing boss 141 includes a first convex portion 143 and a second convex portion 144. The first convex portion 143 is arranged around the explosion-proof disc 142. The first convex portion 143 is limitedly assembled in the limiting groove 123, and the first convex portion 143 is flush with the top cover 12, and the second convex portion 144 is stacked on the first convex portion 143. The explosion-proof valve 14 is designed as a separate part. The first convex portion 143 is an annular plane. The first convex portion 143 is assembled with the limiting groove 123 of the top cover 12 and is flush with the top cover 12 to form a butt welding area, so as to facilitate the accumulation and grinding of solder, so that the first convex portion 143 after welding forms a complete sealing plane with the top cover 12. The annular plane of the first convex portion 143 is the annular second convex portion 144 inwardly, and the second convex portion 144 greatly improves the mechanical resistance of the explosion-proof valve 14, and the inner side of the second convex portion 144 is the explosion-proof discharge disc area.

[0044] The thickness of the first protrusion 143 may be greater than the thickness of the explosion-proof disc 142, thereby further enhancing the mechanical resistance of the explosion-proof valve 14. Of course, in another embodiment, the thickness of the first protrusion 143 may also be the same as the thickness of the explosion-proof disc 142, and the first protrusion 143 is mainly used to fix the explosion-proof valve 14 on the top cover 12.

[0045] See also Figure 6 , Figure 6 This application provides Figure 4 A schematic cross-sectional view of another embodiment along direction III-III.

[0046] The reinforcing boss 141 also includes a third convex portion 145, which is arranged around the second convex portion 144 and connected to the explosion-proof disc 142. The third convex portion 145 sinks relative to the second convex portion 144, and the second convex portion 144, the third convex portion 145, and the explosion-proof disc 142 sink in sequence to form a step structure. The characteristics of the third convex portion 145 can reduce the thickness difference between the second convex portion 144 and the explosion-proof disc 142, thereby improving the manufacturability of the explosion-proof valve 14 of this structural type. In addition, this structure can ensure that the second convex portion 144 has sufficient thickness to ensure that the reinforcing convex portion has sufficient strength.

[0047] The explosion-proof valve 14 may be made of aluminum, stainless steel, copper, etc.

[0048] Please continue reading Figure 2and Figure 3 The battery cover assembly further includes a protective sheet 16, which is attached to the reinforcing boss 141 to cover the explosion-proof sheet 142. The protective sheet 16 can be made of a transparent material so that the use status of the explosion-proof sheet 142 can be directly observed.

[0049] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A battery top cover assembly, the battery top cover assembly is used to cover the shell of a single battery, characterized in that: The battery top cover assembly comprises: A top cover is provided with an explosion-proof hole, and the top cover is used to seal the shell; The explosion-proof valve comprises a reinforcing boss and an explosion-proof disk, wherein the reinforcing boss is arranged around the explosion-proof disk, the thickness of the reinforcing boss is greater than that of the explosion-proof disk, the reinforcing boss is connected to the top cover, and the explosion-proof disk covers the explosion-proof hole; The top cover is provided with a limiting groove around the explosion-proof hole, and the reinforcing boss is limitedly assembled in the limiting groove; The reinforcing boss comprises a first convex portion and a second convex portion, the first convex portion is arranged around the explosion-proof plate, the first convex portion is limitedly assembled in the limiting groove, and the second convex portion is stacked on the first convex portion; The reinforcing boss further includes a third convex portion, the third convex portion is arranged around the second convex portion and connected to the explosion-proof disk, and the third convex portion is sunken relative to the second convex portion to form a step structure; The thickness of the first protrusion is greater than the thickness of the explosion-proof disk.

2. The battery top cover assembly according to claim 1, characterized in that: The reinforcing boss is welded to the top cover.

3. The battery top cover assembly according to claim 1, characterized in that: The first protrusion is flush with the top cover.

4. The battery top cover assembly according to claim 1, characterized in that: The top cover is provided with a chamfer at the edge of the limiting groove.

5. The battery top cover assembly according to claim 1, characterized in that: The battery top cover assembly also includes a protection sheet, which is attached to the reinforcing boss to cover the explosion-proof sheet.

6. The battery top cover assembly according to claim 1, characterized in that: The explosion-proof disk has a thickness of 0.4 mm to 1 mm, and is provided with notches.

7. A single cell battery, characterized in that: The single battery comprises: a battery cell, a shell, and the battery top cover assembly according to any one of claims 1 to 6, the battery cell is assembled in the shell, and the battery top cover assembly covers the shell.

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