Battery cover plate and battery

Abstract

The invention discloses a battery cover plate and a battery, the battery cover plate comprises a cover plate main body, a pole, a current collector and an insulating piece, the current collector comprises a first connecting part, a second connecting part and a fusing part, the first connecting part is used for connecting a battery cell, the fusing part is connected between the first connecting part and the second connecting part, and the second connecting part is used for connecting the battery cell. The cross sectional area of the fusing part is smaller than the cross sectional area of the first connecting part and the cross sectional area of the second connecting part at the same time in the direction perpendicular to the thickness direction of the current collecting piece, the insulating part is connected between the first connecting part and the cover plate main body, the insulating part is provided with a through hole, and the pole penetrates through the through hole and is connected to the second connecting part; the pole is in sealed contact with the inner peripheral wall of the through hole, when the internal pressure of the battery is too large, the pole can be separated from the insulating part, two functions of overcurrent protection and overvoltage protection can be integrated on the battery cover plate, an explosion-proof valve and a safety piece do not need to be additionally arranged, the use safety of the battery can be improved, and the production efficiency of the battery can also be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery cover plate and a battery. BACKGROUND

[0002] With the application of smart wearable products being more and more widely, people's demand for small-size lithium ion button-type secondary rechargeable batteries is also increasing. Button-type batteries are increasingly applied to smart wearable products such as earphones, and the requirements for batteries are also increasing. In order to achieve design requirements and provide better user experience, higher requirements are put forward for batteries, especially improving the safety of button-type batteries, which is an important direction that needs to be solved for button-type batteries at present.

[0003] The existing button-type battery includes a shell, a battery cell and a cover plate. The battery cell is accommodated in the shell, and the cover plate is sealed on the shell. In order to improve the safety of the button-type battery in use, an anti-explosion structure or an anti-short-circuit fuse structure is generally provided on the battery. For example, in order to prevent explosion, a conventional scheme provides an anti-explosion valve on the cover plate to achieve pressure relief and explosion prevention; in order to prevent the battery cell from failing or being damaged due to external short circuit, an insurance sheet is generally provided on the battery cell, and a connecting sheet has an opening. When the current is too large, the connecting sheet is fused. Due to the complex assembly process of the anti-explosion valve and the insurance sheet, the production efficiency of the battery is reduced. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a battery cover plate which can have anti-explosion and anti-short-circuit functions and improve the production efficiency of the battery.

[0005] The present application also provides a battery having the above-mentioned battery cover plate.

[0006] According to the battery cover plate of the first aspect of the present application, the battery cover plate comprises: a cover plate body; a pole; a current collecting sheet comprising a first connecting portion, a second connecting portion and a fuse portion, the first connecting portion being used for connecting the battery cell, the fuse portion being connected between the first connecting portion and the second connecting portion, and the cross-sectional area of the fuse portion being smaller than the cross-sectional area of the first connecting portion and the cross-sectional area of the second connecting portion in a direction perpendicular to the thickness direction of the current collecting sheet; an insulating piece connected between the first connecting portion and the cover plate body, the insulating piece being provided with a through hole, the pole being arranged in the through hole and connected to the second connecting portion, the pole being in sealing contact with the inner peripheral wall of the through hole, and the pole being capable of being separated from the insulating piece when the internal pressure of the battery is too large.

[0007] The battery cover plate according to the embodiment of the present application has at least the following beneficial effects: By setting a fuse part on the current collector tab, when the battery is externally short-circuited, an excessive current can melt the fuse part, so that the first connecting part and the second connecting part are disconnected to prevent the damage of the battery cell, when the internal pressure of the battery is too large, the pole can be separated from the insulating part, the functions of overcurrent protection and overpressure protection can be integrated on the battery cover plate, the internal structure of the battery can be simplified, the explosion-proof valve and the fuse disc do not need to be additionally set, the number of parts and the assembly process can be reduced, the use safety of the battery can be improved, and the production efficiency of the battery can be improved.

[0008] According to some embodiments of the present application, a groove is formed between the first connecting part, the second connecting part and the fuse part, and the groove penetrates through both sides of the thickness direction of the current collector tab.

[0009] According to some embodiments of the present application, the thicknesses of the first connecting part, the second connecting part and the fuse part are equal.

[0010] According to some embodiments of the present application, the first connecting part, the second connecting part and the fuse part are of an integrated structure.

[0011] According to some embodiments of the present application, the pole includes a first protrusion and a second protrusion connected to the first protrusion, the first protrusion and the second protrusion are coaxially arranged, the diameter of the first protrusion is smaller than that of the second protrusion, the first protrusion is arranged in the through hole and in sealing contact with the inner wall of the through hole, and the second protrusion is arranged in the cover plate body.

[0012] According to some embodiments of the present application, the fuse part has a first end and a second end, the first end is connected to the first connecting part, the second end is connected to the second connecting part, and the width of the fuse part gradually decreases from the first end to the second end.

[0013] According to some embodiments of the present application, in a direction perpendicular to the thickness direction of the current collector tab, the cross-sectional area of the first connecting part is greater than that of the second connecting part.

[0014] According to some embodiments of the present application, the minimum cross-sectional area of the fuse part is n, the minimum cross-sectional area of the second connecting part is m, and 0.1m≤n

[0015] According to some embodiments of the present application, the diameter of the second connecting part is less than or equal to the diameter of the through hole, and the second connecting part is coaxially arranged with the pole.

[0016] The battery according to the second aspect of the present application comprises: A shell is provided with a receiving cavity; A battery cell is accommodated in the receiving cavity; The battery cover plate described in the above embodiment, the cover plate body covers the accommodating cavity, and the first connecting part is connected to the battery cell.

[0017] The battery according to the second aspect of the present application has at least the following beneficial effects: The battery cover plate according to the first aspect of the present application has the following beneficial effects: when the battery is externally short-circuited, the excessive current can melt the fuse part, so that the first connecting part and the second connecting part are disconnected, thereby preventing the battery cell from being damaged; when the internal pressure of the battery is too large, the pole can be separated from the insulating part, thereby integrating the overcurrent protection and the overpressure protection on the battery cover plate, simplifying the internal structure of the battery, and reducing the number of parts and the assembly process, thereby improving the safety of the battery and the production efficiency of the battery.

[0018] Additional aspects and advantages of the present application will be given in part in the following description, become apparent from the following description, or be understood by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0019] The present application will be further described below in conjunction with the drawings and embodiments, wherein: Figure 1 The structure diagram of the battery according to an embodiment of the present application; Figure 2 The exploded view of the battery according to an embodiment of the present application; Figure 3 The exploded view of the battery cover plate according to an embodiment of the present application; Figure 4 The top view of the battery according to an embodiment of the present application; Figure 5 The sectional view along line A-A in FIG. 4; Figure 4 The sectional view along line A-A in FIG. 4; Figure 6 The sectional view along line A-A in FIG. 4; Figure 5 The enlarged view of part B in FIG. 4.

[0020] LIST OF REFERENCE NUMBERS Cover plate body 100, pole 200, first protrusion 210, second protrusion 220, current collector 300, groove 301, first connecting part 310, second connecting part 320, fuse part 330, first end 331, second end 332, insulating part 400, through hole 410, shell 500, accommodating cavity 510. DETAILED DESCRIPTION

[0021] Embodiments of the present application are described below in detail with reference to the accompanying drawings, wherein the same or similar components are denoted by the same or similar reference numerals throughout the drawings. The embodiments described below are exemplary only, and are not intended to limit the present application.

[0022] In the description of the present application, it should be understood that the relative description of position, such as up, down, etc., is based on the position or location relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular position, be constructed and operated in a particular position, and therefore cannot be understood as a limitation of the present application.

[0023] In the description of the present application, the plural refers to more than two. If there is a description of the first, the second, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the sequence of technical features indicated.

[0024] In the description of the present application, unless otherwise explicitly limited, the words such as arrangement, installation, connection, etc. should be broadly understood, and those skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0025] In the related art, the button cell includes a shell, a battery cell and a cover plate, the battery cell is accommodated in the shell, and the cover plate is sealed on the shell. In order to improve the use safety of the button cell, a anti-explosion structure or an anti-short circuit fuse structure is generally arranged on the battery. For example, in order to prevent explosion, a conventional scheme sets an anti-explosion valve on the cover plate to achieve pressure relief and explosion prevention; in order to prevent the battery cell from being disabled or damaged due to external short circuit, an insurance sheet is generally arranged on the battery cell, and a connecting sheet is provided with an opening, and when the current is too large, the connecting sheet is fused. Due to the complex assembly process of the anti-explosion valve and the insurance sheet, the production efficiency of the battery is reduced.

[0026] Referring to Figures 2 to 6The battery cover plate of the first aspect embodiment of the present application comprises a cover plate body 100, a pole 200, a current collector 300, and an insulating piece 400, the current collector 300 comprises a first connecting part 310, a second connecting part 320, and a fuse part 330, the first connecting part 310 is used for connecting a battery cell, the fuse part 330 is connected between the first connecting part 310 and the second connecting part 320, in a direction perpendicular to the thickness direction of the current collector 300, the cross-sectional area of the fuse part 330 is smaller than the cross-sectional area of the first connecting part 310 and the cross-sectional area of the second connecting part 320 at the same time, the insulating piece 400 is connected between the first connecting part 310 and the cover plate body 100, the insulating piece 400 is provided with a through hole 410, the pole 200 is arranged in the through hole 410 and connected to the second connecting part 320, the pole 200 is in sealing contact with the inner wall of the through hole 410, when the internal pressure of the battery is too large, the pole 200 can be separated from the insulating piece 400, the battery cover plate can integrate the functions of overcurrent protection and overpressure protection, the internal structure of the battery can be simplified, an explosion-proof valve and a fuse piece do not need to be additionally arranged, the number of parts and the assembly process can be reduced, the use safety of the battery can be improved, and the production efficiency of the battery can be improved.

[0027] For example, by arranging the fuse part 330 on the current collector 300, when the battery is externally short-circuited, excessive current can melt the fuse part 330, so that the first connecting part 310 and the second connecting part 320 are disconnected, to prevent the battery cell from being damaged, when the internal pressure of the battery is too large, the pole 200 can be separated from the insulating piece 400, the battery cover plate can integrate the functions of overcurrent protection and overpressure protection, the internal structure of the battery can be simplified, an explosion-proof valve and a fuse piece do not need to be additionally arranged, the number of parts and the assembly process can be reduced, the use safety of the battery can be improved, and the production efficiency of the battery can be improved.

[0028] It should be noted that the insulating piece 400 is made of acid-resistant materials such as PE, PP, and PFA, the pole 200 is made of metal materials with good electrical conductivity, the insulating piece 400 is integrally formed on the pole 200 by injection molding, on the one hand, the bonding force between the insulating piece 400 and the pole 200 can be ensured, on the other hand, when the internal pressure of the battery is too large, the internal pressure of the battery can overcome the bonding force between the insulating piece 400 and the pole 200, so that the insulating piece 400 and the pole 200 are separated, the battery can be deflated at the through hole 410 to prevent the battery from exploding, thereby improving the use safety of the battery.

[0029] It can be understood that the cover plate body 100, the current collector 300, and the insulating piece 400 are fixedly connected by hot pressing, which can simplify the assembly process of the battery cover plate, thereby improving the production efficiency of the battery, which is not limited herein.

[0030] In the embodiment, the recess 301 is formed between the first connecting portion 310, the second connecting portion 320 and the fusing portion 330, and the recess 301 penetrates through both sides of the thickness direction of the current collector tab 300. By arranging the recess 301, the fusing portion 330 can be easily processed, and the heat and current density of the fusing portion 330 can be concentrated, thereby improving the accuracy and response speed of the overcurrent fusing.

[0031] In the embodiment, the thicknesses of the first connecting portion 310, the second connecting portion 320 and the fusing portion 330 are equal, and the current collector tab 300 can be formed by one-time stamping process, so that the thicknesses of the first connecting portion 310, the second connecting portion 320 and the fusing portion 330 are uniform, and the mechanical strength weakness or uneven current distribution caused by uneven thicknesses can be avoided. The production process of the current collector tab 300 can be simplified, and the manufacturing cost thereof can be reduced.

[0032] In the embodiment, the first connecting portion 310, the second connecting portion 320 and the fusing portion 330 are integrated, so that the number of molds can be reduced, thereby reducing the production and manufacturing cost of the molds and the production and manufacturing cost of the battery cover plate.

[0033] As another embodiment, the first connecting portion 310, the second connecting portion 320 and the fusing portion 330 can also be fixedly connected by welding, and the welding methods include but are not limited to resistance welding, laser welding or ultrasonic welding.

[0034] In the embodiment, the pole post 200 includes a first protrusion 210 and a second protrusion 220 connected to the first protrusion 210. The first protrusion 210 and the second protrusion 220 are coaxially arranged, and the diameter of the first protrusion 210 is smaller than that of the second protrusion 220. The first protrusion 210 is arranged in the through hole 410 and in sealing contact with the inner wall of the through hole 410. The second protrusion 220 is arranged in the cover plate body 100, so that the sealing reliability and explosion-proof response speed of the sealing member can be improved.

[0035] For example, the pole post 200 has a stepped structure. The first protrusion 210 with a smaller diameter is in sealing cooperation with the through hole 410, and the contact area between the first protrusion 210 and the through hole 410 is relatively small, so that the sealing reliability of the insulating member 400 can be improved. Moreover, the smaller contact area makes the sealing force to be overcome during pressure relief relatively small, which is beneficial to timely separation of the pole post 200 and the insulating member 400 when the set pressure is reached, and the sealing reliability and explosion-proof response speed of the sealing member can be improved.

[0036] In the embodiment, the fusing portion 330 has a first end 331 and a second end 332, the first end 331 is connected to the first connecting portion 310, and the second end 332 is connected to the second connecting portion 320. In the direction from the first end 331 to the second end 332, the width of the fusing portion 330 gradually decreases, the heat effect during overcurrent can be concentrated on the second end 332, and the fusing is ensured to occur at the second end 332, thereby improving the accuracy and consistency of overcurrent protection.

[0037] In the embodiment, in the direction perpendicular to the thickness direction of the current collecting sheet 300, the cross-sectional area of the first connecting portion 310 is greater than that of the second connecting portion 320, which helps to reduce the internal resistance of the battery and the heat generation during normal operation.

[0038] For example, by increasing the size of the first connecting portion 310, the first connecting portion 310 can have a larger current or a lower resistance, which can reduce the resistance and heat generation of the path from the battery cell to the fusing portion 330, and help to reduce the internal resistance of the battery and the heat generation during normal operation.

[0039] In the embodiment, the minimum cross-sectional area of the fusing portion 330 is n, and the minimum cross-sectional area of the second connecting portion 320 is m, which satisfies: 0.1m≤n<m, which can ensure that the fusing portion 330 can be preferentially and reliably fused during overcurrent.

[0040] In the embodiment, the diameter of the second connecting portion 320 is less than or equal to the diameter of the through hole 410, and the second connecting portion 320 is coaxially arranged with the pole 200. When the pole 200 is separated from the insulating member 400 under the action of internal pressure, a smooth discharge path is provided for the high-pressure gas, and the second connecting portion 320 avoids hindering the gas flow.

[0041] Referring to Figure 1 , Figure 2 The battery of the second aspect embodiment of the present application comprises a shell 500, a battery cell, and the battery cover plate of the first aspect embodiment of the present application. The shell 500 is provided with a receiving cavity 510, the battery cell is accommodated in the receiving cavity 510, and the cover plate body 100 is sealed in the receiving cavity 510. The first connecting portion 310 is connected to the battery cell. The battery cover plate can integrate overcurrent protection and overvoltage protection functions, can simplify the internal structure of the battery, does not need to additionally provide a burst disc and a fuse, can reduce the number of parts and assembly processes, can improve the use safety of the battery, and can improve the production efficiency of the battery.

[0042] For example, by setting the fusing portion 330 on the current collecting sheet 300, when the battery is externally short-circuited, the excessive current can fuse the fusing portion 330, so that the first connecting portion 310 and the second connecting portion 320 are disconnected to prevent the damage of the battery cell, when the internal pressure of the battery is excessive, the pole 200 can be separated from the insulating piece 400, the functions of the overcurrent protection and the overpressure protection can be integrated on the battery cover plate, the internal structure of the battery can be simplified, the explosion-proof valve and the fuse sheet do not need to be additionally set, the number of parts and the assembly process can be reduced, the use safety of the battery can be improved, and the production efficiency of the battery can be improved.

[0043] Since the battery adopts all the technical solutions of the battery cover plate of the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are possessed, and details are not described herein.

[0044] The embodiments of the application are described in detail above in combination with the drawings, but the application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application.

Claims

1. A battery cover, characterized in that, include: Cover plate body (100); pole (200); The current collector (300) includes a first connecting part (310), a second connecting part (320), and a fuse part (330). The first connecting part (310) is used to connect the battery cell. The fuse part (330) is connected between the first connecting part (310) and the second connecting part (320) along a direction perpendicular to the thickness direction of the current collector (300). The cross-sectional area of ​​the fuse part (330) is smaller than both the cross-sectional area of ​​the first connecting part (310) and the cross-sectional area of ​​the second connecting part (320). An insulating component (400) is connected between the first connecting part (310) and the cover plate body (100). The insulating component (400) has a through hole (410). The electrode post (200) passes through the through hole (410) and is connected to the second connecting part (320). The electrode post (200) is in sealed contact with the inner peripheral wall of the through hole (410). When the internal pressure of the battery is too high, the electrode post (200) can be separated from the insulating component (400).

2. The battery cover according to claim 1, characterized in that: A groove (301) is formed between the first connecting part (310), the second connecting part (320) and the fuse part (330), and the groove (301) penetrates both sides of the current collector (300) in the thickness direction.

3. The battery cover according to claim 1, characterized in that: The thicknesses of the first connecting portion (310), the second connecting portion (320), and the fused portion (330) are equal.

4. The battery cover according to claim 1, characterized in that: The first connecting part (310), the second connecting part (320) and the fuse part (330) are an integral structure.

5. The battery cover according to claim 1, characterized in that: The pole post (200) includes a first protrusion (210) and a second protrusion (220) connected to the first protrusion (210). The first protrusion (210) and the second protrusion (220) are coaxially arranged, and the diameter of the first protrusion (210) is smaller than the diameter of the second protrusion (220). The first protrusion (210) passes through the through hole (410) and is in sealing contact with the inner peripheral wall of the through hole (410). The second protrusion (220) passes through the cover plate body (100).

6. The battery cover according to claim 1, characterized in that: The fusible portion (330) has a first end (331) and a second end (332). The first end (331) is connected to the first connecting portion (310), and the second end (332) is connected to the second connecting portion (320). The width of the fusible portion (330) gradually decreases from the first end (331) to the second end (332).

7. The battery cover according to claim 1, characterized in that: Along a direction perpendicular to the thickness direction of the current collector (300), the cross-sectional area of ​​the first connecting portion (310) is greater than the cross-sectional area of ​​the second connecting portion (320).

8. The battery cover according to claim 7, characterized in that: The minimum cross-sectional area of ​​the fuse part (330) is n, and the minimum cross-sectional area of ​​the second connecting part (320) is m, satisfying: 0.1m≤n<m.

9. The battery cover according to claim 1, characterized in that: The diameter of the second connecting part (320) is less than or equal to the diameter of the through hole (410), and the second connecting part (320) is coaxially arranged with the pole post (200).

10. A battery, characterized in that, include: The housing (500) is provided with a receiving cavity (510); The battery cell is housed within the receiving cavity (510); The battery cover according to any one of claims 1 to 9, wherein the cover body (100) covers the receiving cavity (510), and the first connecting part (310) is connected to the battery cell.

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