Power battery

Abstract

The invention discloses a power battery which comprises a shell, a roll core, a collector plate and an anti-explosion valve plate, the shell sleeves the roll core and comprises a shell bottom, a boss part protruding upwards is formed on the shell bottom, an exhaust hole penetrating through the shell bottom is formed in the position, spaced from the boss part, of the shell bottom, a circle of reinforcing rib protrudes upwards from the periphery of the exhaust hole of the shell bottom, and the anti-explosion valve plate is arranged in the shell bottom. The upper side of the flow collecting disc is welded to the end of the roll core, the lower side of the flow collecting disc is welded to the boss part in an attached mode, the flow collecting disc is supported by the reinforcing ribs, and the anti-explosion valve plate is arranged at the exhaust hole. According to the application, the balance and compactness of the internal structure of the power battery can be effectively improved, the explosion risk caused by the blockage of the exhaust hole after the deformation of the collector plate can be effectively avoided, and the problem that the deformation of the explosion-proof valve plate / the influence on the valve opening consistency caused by the deformation of the shell when the internal air pressure of the power battery is increased can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a power battery. Background Art

[0002] At present, lithium-ion / sodium-ion power batteries have gradually become mainstream products in the new energy industry due to their high energy density, good capacity consistency, and ability to support high-rate charge and discharge. Conventional power battery structures generally have only one injection hole, and there are the following common problems:

[0003] Cylindrical aluminum shell power batteries have many advantages: low cost, lightweight, etc. However, since the aluminum shell material is relatively soft, it is easy to deform significantly when the abnormal internal pressure inside the battery increases, thus affecting the consistency of the explosion-proof valve opening, bringing safety risks to the power battery.

[0004] With the optimization of power battery structure and the increase of rate demand, the bulge formed on the bottom wall of the liquid injection groove in the middle of the shell bottom is partially fitted with the collecting plate and laser penetration welded, resulting in a gap between the surrounding area of ​​the collecting plate and the shell bottom. When the power battery is subjected to rolling test or vehicle loading vibration, the power battery lacks balance and compactness inside, and is prone to the risk of power battery short circuit.

[0005] When the power battery is abnormal and the internal air pressure increases, when the valve is opened to release the pressure, the rapid pressure release causes the collector plate to deform and fill the gap with the shell bottom. After the collector plate is deformed, the through holes in the collector plate that can be used for exhaust are prone to random skewness, causing the pressure relief valve to be blocked in non-hole positions, posing an explosion risk. Summary of the invention

[0006] The purpose of this application is to provide a power battery that can solve at least one technical problem in the background technology.

[0007] In order to achieve the above-mentioned purpose, the present application provides a power battery, which includes a shell, a winding core, a collecting plate and an explosion-proof valve plate, the shell being sleeved on the outside of the winding core, the shell including a shell bottom, a boss portion protruding upward is formed on the shell bottom, an exhaust hole penetrating the shell bottom is opened at a position spaced apart from the boss portion, the shell bottom has a circle of reinforcing ribs protruding upward from the periphery of the exhaust hole, the upper side of the collecting plate is welded to the end of the winding core, the lower side of the collecting plate is welded to the boss portion, the reinforcing ribs support the collecting plate, and the explosion-proof valve plate is arranged at the exhaust hole.

[0008] Optionally, the reinforcing rib has an upper surface that fits the collecting plate, and a plurality of connecting grooves that penetrate the reinforcing rib inside and outside are formed on the upper surface.

[0009] Optionally, a plurality of through holes are distributed on the collecting plate, and the through holes can allow gas to pass through.

[0010] Optionally, a plurality of through holes are distributed on the collecting plate, and the through holes can allow gas to pass through; at least part of the areas of some of the through holes face the space inside the reinforcing rib.

[0011] Optionally, the collecting plate is punched upward to form at least two sinkers, the collecting plate is welded to the end of the winding core through the sinkers, and the through hole is formed in an unpunched area of ​​the collecting plate.

[0012] Optionally, the collecting plate is punched upward to form at least two sinks, each of which defines a sink groove, and a partial area of ​​at least one of the sink grooves faces the space inside the reinforcing rib to form an exhaust channel.

[0013] Optionally, the inner side wall of the reinforcing rib and the side wall of the exhaust hole are spaced apart inside and outside, so that a platform surface is formed between the inner side wall of the reinforcing rib and the side wall of the exhaust hole, and the outer edge of the explosion-proof valve sheet is attached to the platform surface.

[0014] Optionally, the bottom of the exhaust hole expands outward to form an annular step surface for film sticking.

[0015] Optionally, the reinforcing rib and the exhaust hole are formed by integral stamping / stretching / cold extrusion.

[0016] Optionally, a liquid injection hole is formed in the middle of the boss portion.

[0017] In the embodiment of the present application, a circle of reinforcing ribs protrudes upward from the outer periphery of the exhaust hole at the bottom of the shell, and the reinforcing ribs support the collector plate, so that in addition to the boss portion and the collector plate being partially welded together at the bottom of the shell, there are also reinforcing ribs that can support other positions of the collector plate upward, which can effectively improve the balance and compactness of the internal structure of the power battery, and thus avoid the safety risks that may be caused by insufficient balance / compactness. Moreover, when the internal air pressure of the power battery increases and the valve is opened to release pressure, the support of the collector plate by the reinforcing ribs can effectively avoid the explosion risk caused by the deformation of the collector plate and the blocking of the exhaust hole. In addition, due to the setting of the reinforcing ribs, the strength of the position where the explosion-proof valve plate is set is increased. When the shell material is soft, it can effectively improve the problem of deformation of the explosion-proof valve plate / affected consistency of the valve opening caused by deformation of the shell when the internal air pressure of the power battery increases. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the power battery of an embodiment of the present application.

[0019] Figure 2 It is a schematic diagram of the cross-sectional structure of the power battery of an embodiment of the present application.

[0020] Figure 3It is a cross-sectional schematic diagram of the local structure of the power battery of an embodiment of the present application.

[0021] Figure 4 A schematic cross-sectional view of the local structure of the shell and the explosion-proof valve in an embodiment of the present application.

[0022] Figure 5 A schematic cross-sectional view of a local structure of a shell according to an embodiment of the present application.

[0023] Figure 6 Schematic diagram of the three-dimensional structure of the winding core and the collecting plate in the embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to explain the technical content, structural features, and achieved effects of the present application in detail, the following is a detailed description in conjunction with the implementation methods and the accompanying drawings.

[0025] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0026] See also Figures 1 to 6 The embodiment of the present application discloses a power battery, which includes a shell 10, a winding core 20, a current collecting plate 30 and an explosion-proof valve plate 40. The shell 10 is sleeved on the outside of the winding core 20, and the shell 10 includes a shell bottom 11. A boss portion 12 protruding upward (i.e., toward the inside of the power battery) is formed on the shell bottom 11. A vent 13 penetrating the shell bottom 11 is provided at a position spaced apart from the boss portion 12. A circle of reinforcing ribs 14 protrude upward from the outer periphery of the vent 13 on the shell bottom 11. The upper side of the current collecting plate 30 is welded to the end of the winding core 20, and the lower side of the current collecting plate 30 is welded to the boss portion 12. The reinforcing ribs 14 support the current collecting plate 30, and the explosion-proof valve plate 40 is arranged at the vent 13.

[0027] In the embodiment of the present application, the shell bottom 11 protrudes upward from the periphery of the exhaust hole 13 with a circle of reinforcing ribs 14, and the reinforcing ribs 14 support the collector plate 30, so that in addition to the partial welding of the boss portion 12 and the collector plate 30, the shell bottom 11 also has reinforcing ribs 14 that can support the other positions of the collector plate 30 upward, which can effectively improve the balance and compactness of the internal structure of the power battery, and thus avoid the safety risks that may be caused by insufficient balance / compactness. Moreover, when the internal air pressure of the power battery increases and the valve is opened to release pressure, the support of the collector plate 30 by the reinforcing ribs 14 can effectively avoid the explosion risk caused by the deformation of the collector plate 30 and the blocking of the exhaust hole 13. In addition, due to the setting of the reinforcing ribs 14, the strength of the location where the explosion-proof valve plate 40 is set is increased. When the material of the shell 10 is relatively soft, it can effectively improve the problem that the deformation of the shell 10 when the internal air pressure of the power battery increases causes the deformation of the explosion-proof valve plate 40 / the consistency of the opening of the valve is affected.

[0028] In some embodiments, the reinforcing rib 14 has an upper surface 141 that fits with the collecting plate 30, and a plurality of connecting grooves 142 that penetrate the reinforcing rib 14 from inside to outside are provided on the upper surface 141. Since the reinforcing rib 14 can fit with the collecting plate 30 through its upper surface 141, it is helpful to ensure the supporting effect. By providing the connecting grooves 142 that penetrate from inside to outside on the upper surface 141 of the reinforcing rib 14, when the valve is opened to release pressure, the gas outside the reinforcing rib 14 can flow into the space inside the reinforcing rib 14 (the space surrounded by the reinforcing rib 14) through the connecting grooves 142, and then can be discharged outward from the exhaust hole 13, which is conducive to rapid pressure release.

[0029] Specifically, a plurality of communication grooves 142 are distributed at equal intervals on the upper surface 141 of the reinforcing rib 14. Of course, the present invention is not limited thereto.

[0030] Specifically, the connecting groove 142 may be a groove with a V-shaped or U-shaped cross section. Of course, the specific form of the connecting groove 142 is not specifically limited, as long as it can penetrate the reinforcing rib 14 inside and outside to connect the space outside the reinforcing rib 14 with the space inside the reinforcing rib 14.

[0031] In a specific example, the depth of the communication groove 142 is H*1 / 3 to H*1 / 2, where H is the height of the reinforcing rib 14 .

[0032] In some embodiments, the height H of the reinforcing rib 14 is 0.3 mm to 0.8 mm, and the width W is 0.8 mm to 2.5 mm. Of course, this is not limited to this.

[0033] In some embodiments, the collecting plate 30 is provided with a plurality of through holes 31 for gas to pass through, that is, when the valve is opened for exhaust, the internal gas can first enter the space between the collecting plate 30 and the shell bottom 11 through the through holes 31, and then be discharged to the outside through the exhaust holes 13.

[0034] Specifically, after the gas enters the space between the collecting plate 30 and the shell bottom 11 , it can enter the space inside the reinforcing rib 14 through the connecting groove 142 on the reinforcing rib 14 , and then be discharged outward through the exhaust hole 13 .

[0035] Specifically, at least a portion of at least one through hole 31 faces the space inside the reinforcing rib 14 , so that at least a portion of the gas exhausted from the at least one through hole 31 can directly enter the space inside the reinforcing rib 14 , facilitating rapid exhaustion from the exhaust hole 13 .

[0036] Specifically, the collecting plate 30 is punched upward to form at least two sinkers 32 , each sinker 32 defines a sink groove 33 , the collecting plate 30 is welded to the end of the winding core 20 through the sinkers 32 , and the through hole 31 is formed in the unpunched area of ​​the collecting plate 30 .

[0037] Furthermore, a portion of at least one of the sink grooves 33 faces the space inside the reinforcing rib 14 to form an exhaust channel, and at least part of the gas exhausted from the through hole 31 can pass through the exhaust channel and then be exhausted to the outside through the exhaust hole 13. Of course, the sink groove 33 is not limited to facing the space inside the reinforcing rib 14 to form an exhaust channel.

[0038] In the specific example, in addition to the central through hole 311 corresponding to the winding core through hole 21 and the injection hole 16 on the shell bottom 11, the current collecting plate 30 is also provided with three through holes 312 surrounding the central through hole 311. In addition, three sinkers 32 arranged at intervals in the circumferential direction are formed on the current collecting plate 30, and a through hole 312 is respectively provided between adjacent sinkers 32.

[0039] In some embodiments, the collecting plate 30 is punched upward to form at least two sinks 32, each sink 32 defines a sink 33, and a portion of at least one sink 33 faces the space inside the reinforcing rib 14 to form an exhaust channel. The gas outside the reinforcing rib 14 can pass through the exhaust channel and be discharged outward from the exhaust hole 13. Of course, the sink 33 is not limited to facing the space inside the reinforcing rib 14 to form an exhaust channel.

[0040] When a plurality of connecting grooves 142 are provided on the reinforcing rib 14 and the exhaust passage is formed by utilizing the sinking groove 33, it is beneficial to quickly exhaust the gas.

[0041] In some embodiments, the inner side wall of the reinforcing rib 14 and the side wall of the exhaust hole 13 are arranged in an inner and outer space, so that a platform surface 131 is formed between the inner side wall of the reinforcing rib 14 and the side wall of the exhaust hole 13, and the outer edge of the explosion-proof valve plate 40 is attached to the platform surface 131. Of course, the installation of the explosion-proof valve plate 40 is not limited to this form.

[0042] Specifically, the explosion-proof valve plate 40 is sealed by laser welding after being attached to the platform surface 131 .

[0043] It can be understood that the explosion-proof valve plate 40 is lower than the reinforcing rib 14 as a whole and is spaced apart from the collecting plate 30 .

[0044] In some embodiments, the bottom of the vent hole 13 expands outward to form an annular step surface 132 for film application. Since the annular step surface 132 for film application is formed at the bottom of the vent hole 13, the height of the power battery will not be affected when film application is performed.

[0045] In some embodiments, the reinforcing rib 14 and the vent hole 13 are formed by integral stamping / stretching / cold extrusion. Of course, this is not limited to this.

[0046] In some embodiments, a liquid injection hole 16 is formed in the middle of the boss portion 12 .

[0047] Specifically, due to the formation of the boss portion 12 , a liquid injection groove 17 is formed on the upper side thereof.

[0048] In some embodiments, the explosion-proof valve plate 40 is made of MFX or other aluminum materials.

[0049] The above disclosure is only a preferred example of the present application, and its role is to facilitate the technical personnel in this field to understand and implement it. Of course, it cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the scope of the patent application of the present application still fall within the scope covered by the present application.

Claims

1. A power battery, characterized in that: The power battery includes a shell, a winding core, a current collecting disk and an explosion-proof valve sheet. The shell is sleeved on the outside of the winding core, and the shell includes a shell bottom. A boss portion protruding upward is formed on the shell bottom. An exhaust hole penetrating the shell bottom is opened at a position spaced apart from the shell bottom and the boss portion. A circle of reinforcing ribs protrudes upward from the shell bottom at the periphery of the exhaust hole. The upper side of the current collecting disk is welded to the end of the winding core, and the lower side of the current collecting disk is welded to the boss portion. The reinforcing ribs support the current collecting disk, and the explosion-proof valve sheet is arranged at the exhaust hole.

2. The power battery according to claim 1, characterized in that: The reinforcing rib has an upper surface that is in contact with the current collecting plate, and a plurality of connecting grooves that penetrate the reinforcing rib inside and outside are formed on the upper surface.

3. The power battery according to claim 1 or 2, characterized in that: The collecting plate is provided with a plurality of through holes, and the through holes can allow gas to pass through.

4. The power battery according to claim 1, characterized in that: The collecting plate is provided with a plurality of through holes, and the through holes can allow gas to pass through; at least a portion of the through holes faces the space inside the reinforcing rib.

5. The power battery according to claim 4, characterized in that: The current collecting plate is punched upward to form at least two sinkers, the current collecting plate is welded to the end of the winding core through the sinkers, and the through hole is formed in a non-punched area of ​​the current collecting plate.

6. The power battery according to claim 1, characterized in that: The collecting plate is punched upward to form at least two sinks, each of which defines a sink groove, and a partial area of ​​at least one of the sink grooves faces the space inside the reinforcing rib to form an exhaust channel.

7. The power battery according to claim 1, characterized in that: The inner side wall of the reinforcing rib and the side wall of the exhaust hole are arranged inwardly and outwardly spaced apart, so that a platform surface is formed between the inner side wall of the reinforcing rib and the side wall of the exhaust hole, and the outer edge of the explosion-proof valve sheet is attached to the platform surface.

8. The power battery according to claim 1, characterized in that: The bottom of the exhaust hole expands outward to form an annular step surface for film sticking.

9. The power battery according to claim 1, characterized in that: The reinforcing rib and the exhaust hole are formed by integral stamping / stretching / cold extrusion.

10. The power battery according to claim 1, characterized in that: A liquid injection hole is formed in the middle of the boss portion.

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