Cylindrical battery

Abstract

The invention provides a cylindrical battery in order to solve the problems that in the prior art, when a battery is subjected to a short circuit or high-temperature storage test, a valve cannot be opened in time for pressure relief and exhaust, and explosion is likely to occur. The battery comprises a shell, a roll core and a collector plate, a liquid injection groove is formed in the middle of the bottom circular plane of the shell; a liquid injection hole is formed in the middle of the liquid injection groove; and a C-shaped pressure relief nick is arranged on the outer side of the circular plane at the bottom of the shell. A through hole is formed in the middle of the collector plate, an annular plane is arranged around the through hole, and an omega-shaped hollowed-out groove is formed around the plane and provided with a plurality of intermittent partitions. According to the battery, multiple technical effects of efficient liquid injection, accurate pressure relief and mechanical stress dispersion are realized through the planarization of the liquid injection groove, the optimization of the angle of the C-shaped pressure relief nick and the design of the omega / line-shaped composite hollow groove, and the problems that a valve cannot be opened in time for pressure relief and exhaust and explosion is easy to occur when the battery is subjected to a short circuit or high-temperature storage test are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a cylindrical battery. Background Art

[0002] At present, lithium-ion / sodium-ion cylindrical batteries have gradually become the mainstream products in the new energy industry due to their high energy density, good capacity consistency, and support for high-rate charge and discharge. While more and more manufacturers are continuously improving the energy density of cylindrical batteries, they are also continuously pursuing their high safety.

[0003] In existing cylindrical power batteries, the pressure relief valve is commonly set on the top cover. However, for thin and long cylindrical power batteries, only a small-sized pressure relief valve can be set. When the battery undergoes short-circuit or high-temperature storage tests, it is unable to open the valve in time to relieve pressure and exhaust gas, and explosion problems are likely to occur, posing safety risks to customers. Summary of the Invention

[0004] The present invention provides a cylindrical battery to solve the problem that in the prior art, when the battery undergoes short-circuit or high-temperature storage tests, it is unable to open the valve in time to relieve pressure and exhaust gas, and explosion is likely to occur.

[0005] The technical solution adopted by the present invention is as follows:

[0006] Furthermore, it includes a housing, a winding core, and a current collector plate;

[0007] In the middle of the bottom circular plane of the housing, there is a liquid injection groove, and in the middle of the liquid injection groove, there is a liquid injection hole; on the outside of the bottom circular plane of the housing, a C-shaped pressure relief notch is provided;

[0008] In the middle of the current collector plate, there is a through hole, around the through hole, there is an annular plane, around the plane, there is an Ω-shaped hollow groove, and the Ω-shaped hollow groove has multiple intermittent partitions.

[0009] Furthermore, the bottom of the liquid injection groove has a planar feature.

[0010] Furthermore, the central angle r between the two ends of the C-shaped pressure relief notch is 15° - 35°;

[0011] Among them, the two ends of the C-shaped pressure relief notch are the connection positions of the two ends of the C-shaped pressure relief notch.

[0012] Furthermore, connecting the Ω-shaped hollow groove, there is a linear hollow groove provided, and the linear hollow groove has intermittent partitions;

[0013] Among them, the linear hollow groove is the hollow groove of the current collector plate.

[0014] Further, during battery assembly, the root of the linear hollow groove is aligned with both ends of the C-shaped pressure relief notch. When the battery is subjected to short circuit or high-temperature storage tests, the root of the linear hollow groove is bent and deformed when the C-shaped pressure relief notch opens the valve.

[0015] Further, the plane around the through hole is attached to the bottom of the liquid injection groove and fixed by laser penetration welding.

[0016] Further, the material of the housing is aluminum.

[0017] Further, the material of the current collector plate is aluminum.

[0018] Further, the housing is formed by integral stamping / stretching / cold extrusion.

[0019] Further, the current collector plate is formed by integral stamping / stretching / cold extrusion.

[0020] The beneficial effects of the present invention are as follows:

[0021] Through the planarization of the liquid injection groove, the angle design of the C-shaped pressure relief notch, and the Ω / linear composite hollow groove design, the present invention achieves multiple technical effects of efficient liquid injection, precise pressure relief, and mechanical stress dispersion, and solves the problem that the battery is prone to explosion due to the inability to open the valve and relieve pressure and exhaust gas in a timely manner during short circuit or high-temperature storage tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 is a cross-sectional view of a cylindrical battery;

[0024] Figure 2 is a top view of the bottom structure of the housing;

[0025] Figure 3 is a top view of the current collector plate structure;

[0026] Figure 4 is a schematic diagram of the alignment state of the current collector plate and the bottom of the housing. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation on the present invention.

[0028] The present invention provides a cylindrical battery to solve the problem that in the prior art, when a battery undergoes a short - circuit or high - temperature storage test, it cannot vent pressure and exhaust gas in time, and is prone to explosion.

[0029] The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present invention.

[0030] The embodiments of the invention will be described in detail below with reference to the drawings.

[0031] This embodiment discloses a cylindrical battery. As shown in the attached Figure 1 to the attached Figure 1 figures, the cylindrical battery includes a housing 1, a wound core 2, and a current collector plate 3. As shown in the attached Figure 1 figures.

[0032] The bottom of the housing 1 is a circular plane, and a liquid injection groove 11 is formed by stamping in the middle thereof. The bottom of the liquid injection groove 11 is a flat structure, and a liquid injection hole 12 is provided at the center for injecting electrolyte. The planar design of the liquid injection groove 11 can improve the sealing performance during liquid injection and is also convenient for subsequent laser welding. A C - type pressure - relief notch 13 is formed on the outer side of the bottom of the housing 1 by a scoring process. The included angle r between the two connection positions of the C - type pressure - relief notch 13 with the center of the circle is 25° (within the range of 15° - 35°). This angle design can not only ensure the pressure - relief sensitivity but also avoid excessive weakening of the housing strength. As shown in the attached Figure 2 figures.

[0033] The current collector plate 3 is an aluminum disc. A through - hole 31 is provided in the middle thereof, and an annular plane 32 is around the through - hole. An Ω - shaped hollow groove 34 is distributed on the outer edge of the annular plane 32, and the Ω - shaped hollow groove 34 is divided by intermittent partitions. An L - shaped hollow groove 35 is connected to the outside of the Ω - shaped hollow groove 33, and the L - shaped hollow groove 35 also has partitions distributed at intervals. The current collector plate 3 is formed by integral cold extrusion. Its annular plane 32 is closely attached to the bottom plane of the liquid injection groove 11 of the housing 1 and is fixed by laser penetration welding to ensure the reliability of electrical connection. As shown in the attachedFigure 3 as shown

[0034] During assembly, adjust the angle of the manifold 3 so that the root 351 of the linear hollow groove 35 is aligned with both ends 132 of the C-shaped pressure relief notch 13. When abnormal gas is generated in the battery, the C-shaped pressure relief notch 13 cracks preferentially, and the gas pressure is conducted to the root 351 of the linear hollow groove 35, prompting the part to undergo a directional bending deformation, thereby expanding the pressure relief channel and preventing the overall explosion of the housing. The intermittent partition 34 design of the Ω-shaped hollow groove 33 can prevent excessive stress concentration and provide a buffer space when the winding core expands. As shown in the appendix Figure 4 as shown

[0035] The housing 1 is formed by stretching aluminum, with a uniform wall thickness and a smooth inner surface. After the injection of electrolyte is completed, the injection hole 12 is sealed by laser to form a sealed solder joint. Tests show that this structure has no leakage after being stored at a high temperature of 150 °C for 240 hours, and the pressure relief response time during the short-circuit test is shortened by 40%, significantly improving the battery safety.

[0036] In this embodiment, through the planarization of the injection groove 11, the angle design of the C-shaped pressure relief notch 13, and the Ω / linear composite hollow groove design, multiple technical effects of efficient injection of electrolyte, precise pressure relief, and mechanical stress dispersion are achieved, solving the problem that the battery is prone to explosion due to the inability to open the valve for pressure relief and exhaust in a timely manner during short-circuit or high-temperature storage tests.

Claims

1. A cylindrical battery, characterized in that: It includes a shell, a winding core, and a collecting plate; A liquid injection groove is provided in the middle of the circular plane at the bottom of the shell, and a liquid injection hole is provided in the middle of the liquid injection groove; a C-shaped pressure relief notch is provided on the outer side of the circular plane at the bottom of the shell; A through hole is provided in the middle of the current collecting plate, an annular plane is provided around the through hole, an Ω-shaped hollow groove is provided around the plane, and the Ω-shaped hollow groove has a plurality of intermittent partitions.

2. The cylindrical battery according to claim 1, characterized in that: The bottom of the liquid injection groove has a plane feature.

3. The cylindrical battery according to claim 1, characterized in that: The center angle r of the two ends of the C-shaped pressure relief notch is 15°-35°; Wherein, the two ends of the C-shaped pressure relief notch are the connection positions of the two ends of the C-shaped pressure relief notch.

4. The cylindrical battery according to claim 1, characterized in that: Connecting the Ω-shaped hollow grooves, there are all provided with a straight-line hollow groove, and the straight-line hollow grooves have intermittent partitions; Wherein, the straight-line hollow groove is the hollow groove of the collecting plate.

5. The cylindrical battery according to claim 3, characterized in that: When the battery is assembled, the root of the I-shaped hollow groove is aligned with both ends of the C-shaped pressure relief notch. When the battery is undergoing a short circuit or high-temperature storage test, the C-shaped pressure relief notch opens the valve, causing the root of the I-shaped hollow groove to bend and deform.

6. The cylindrical battery according to claim 1, characterized in that: The plane around the through hole fits the bottom of the injection groove and is fixed by laser penetration welding.

7. The cylindrical battery according to claim 1, characterized in that: The shell is made of aluminum.

8. The cylindrical battery according to claim 1, characterized in that: The material of the collecting plate is aluminum.

9. The cylindrical battery according to claim 1, characterized in that: The shell is formed by integrated stamping / stretching / cold extrusion.

10. The cylindrical battery according to any one of claims 1 to 9, characterized in that: The collecting plate is formed by integrated stamping / stretching / cold extrusion.

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