Battery negative electrode assembly

Abstract

The utility model provides a battery negative electrode assembly, which is positioned between a battery cell negative electrode and a battery shell, is used for outwards leading out a battery negative electrode, and comprises a negative current collector, a sealing ring, a fixing piece and an insulating assembly, the negative current collector comprises a disc body and a connecting rod; the center of the lower side surface of the disc body is fixedly connected with a connecting rod; a first convex ring and a second convex ring are arranged on the lower side surface of the disc body; the first convex ring and the second convex ring are concentrically distributed around the connecting rod in sequence; the sealing ring is arranged between the first convex ring and the second convex ring; the fixing piece is connected with the connecting rod penetrating through the battery shell and then abuts against the battery shell; the insulating component is arranged between the negative current collector and the battery shell. According to the invention, the sealing ring is limited between the first convex ring and the second convex ring on the negative current collector disc body, so that the sealing ring is not easy to move when the battery is assembled, and the sealing effect is better guaranteed than that of a sealing ring which cannot be positioned.

Description

Technical Field

[0001] This application belongs to the technical field of batteries, and particularly relates to a battery negative electrode assembly. Background Art

[0002] As an energy conversion and storage carrier that can convert chemical energy into electrical energy, lithium-ion batteries have the characteristics of high energy density, high working voltage, long cycle life, no memory effect, and being lightweight and easy to carry. They are widely used in fields such as portable energy storage devices, household energy storage systems, electric vehicle power systems, new energy-powered ships, and backup power for UPS or communication base stations. To avoid affecting the battery service life due to the sealing performance, the structural design of the battery must have high standards of sealing, insulation, and durability. Patent CN202110891817.2 proposes a cylindrical battery with earthquake resistance and impact resistance. The patent adopts the following scheme for the insulation design of the negative electrode: "A negative electrode screw is provided on the upper end surface of the negative electrode current collector. After the negative electrode screw passes through the aluminum shell, a negative electrode connection block is screwed. A negative electrode insulating sleeve and a negative electrode O-ring are provided between the negative electrode connection block and the aluminum shell. The negative electrode O-ring is sleeved on the side of the negative electrode screw to block the electrical connection between the aluminum shell and the negative electrode screw. A negative electrode insulating structure is provided between the negative electrode current collector and the aluminum shell." In the above battery structure, due to the internal screw connection method between the negative electrode connection block and the negative electrode screw, the negative electrode O-ring cannot be closely attached and pressed between the negative electrode screw and the aluminum shell. After the negative electrode assembly operates locked for a period of time and undergoes long-term charge and discharge operations, the compression ratio rebound of the negative electrode O-ring is inconsistent, and there may be a loosening phenomenon, causing poor contact, increasing the battery internal resistance, reducing the battery sealing performance, and being unable to completely isolate air, resulting in serious attenuation of the battery capacity and thus affecting the product cycle life. Summary of the Utility Model

[0003] In view of this, the purpose of this application is to provide a battery negative electrode assembly, which can be tightly connected and not easily loosened, and has good sealing performance, so as to solve the technical problems proposed in the background art.

[0004] The battery negative electrode assembly provided by this application is located between the negative electrode of the battery cell and the battery housing for leading out the battery negative electrode outward, and includes a negative current collector, a sealing ring, a fixing member, and an insulating component;

[0005] The negative current collector includes a disk body and a connecting rod; the upper side of the disk body is connected to the negative electrode of the battery cell, and the center of the lower side of the disk body is fixedly connected to the connecting rod;

[0006] A first convex ring and a second convex ring are provided on the lower side of the disk body; the first convex ring and the second convex ring are concentrically distributed around the connecting rod in sequence;

[0007] The sealing ring is placed between the first convex ring and the second convex ring;

[0008] After the fixing member is connected to the connecting rod passing through the battery case, it abuts against the battery case;

[0009] The insulating assembly is disposed between the negative current collector and the battery case.

[0010] Furthermore, the insulating assembly includes a first insulator, a second insulator, and a third insulator;

[0011] The first insulator is located between the disc body and the battery case for insulating and isolating the disc body and the battery case;

[0012] The second insulator is disposed between the first convex ring and the battery case for insulating and isolating the first convex ring and the battery case;

[0013] The third insulator is disposed between the connecting rod and the battery case for insulating and isolating the connecting rod and the battery case.

[0014] Furthermore, the disc body and the connecting rod are integrally formed.

[0015] Furthermore, the disc body and the connecting rod are welded.

[0016] Furthermore, the connecting rod has an external thread; the fixing member is a nut, and the nut is threadedly connected to the connecting rod.

[0017] Furthermore, the heights of the first convex ring and the second convex ring are both smaller than the thickness of the sealing ring.

[0018] Furthermore, the height of the first convex ring is not less than the height of the second convex ring.

[0019] Furthermore, the sealing ring is an elastic member.

[0020] Furthermore, the insulating assembly is an elastic member.

[0021] This application has the following beneficial effects:

[0022] The present application provides a battery negative electrode assembly. The negative electrode assembly is located between the negative electrode of the battery cell and the battery housing and is used to lead out the negative electrode of the battery outward. It includes a negative current collector, a sealing ring, a fixing member, and an insulating assembly; the negative current collector includes a disc body and a connecting rod; the upper side of the disc body is connected to the negative electrode of the battery cell, and the connecting rod is fixedly connected to the center of the lower side of the disc body; a first convex ring and a second convex ring are provided on the lower side of the disc body; the first convex ring and the second convex ring are concentrically distributed around the connecting rod in sequence; the sealing ring is placed between the first convex ring and the second convex ring; the fixing member is connected to the connecting rod passing through the battery housing and then abuts against the battery housing; the insulating assembly is arranged between the negative current collector and the battery housing. By restricting the sealing ring between the first convex ring and the second convex ring on the disc body of the negative current collector, the sealing ring is not easily displaced during battery assembly, and the sealing effect is more guaranteed than that of a sealing ring that cannot be positioned. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 FIG. is an exploded schematic view of a battery negative electrode assembly provided by some embodiments of the present application,

[0024] Figure 2 FIG. is a cross-sectional schematic view of a battery negative electrode assembly provided by some embodiments of the present application.

[0025] DESCRIPTION OF REFERENCE NUMERALS:

[0026] 100. Negative electrode of the battery cell,

[0027] 200. Battery housing,

[0028] 300. Negative current collector,

[0029] 310. Disc body,

[0030] 311. First convex ring,

[0031] 312. Second convex ring,

[0032] 320. Connecting rod,

[0033] 400. Sealing ring,

[0034] 500. Fixing member,

[0035] 600. Insulating assembly,

[0036] 610. First insulator,

[0037] 620. Second insulator,

[0038] 630. Third insulator. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant accompanying drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0040] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. On the contrary, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "upper", "lower", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only embodiments.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used in the specification of the present application herein are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0042] The present application provides a battery negative electrode assembly. The negative electrode assembly is located between the negative electrode 100 of the battery cell and the battery housing 200 and is used to lead out the battery negative electrode outward. It includes a negative current collector 300, a sealing ring 400, a fixing member 500 and an insulating assembly 600; the negative current collector 300 includes a disk body 310 and a connecting rod 320; the upper side of the disk body 310 is connected to the negative electrode 100 of the battery cell, and the connecting rod 320 is fixedly connected to the center of the lower side of the disk body 310; a first convex ring 311 and a second convex ring 312 are provided on the lower side of the disk body 310; the first convex ring 311 and the second convex ring 312 are concentrically distributed around the connecting rod 320 in sequence; the sealing ring 400 is placed between the first convex ring 311 and the second convex ring 312; the fixing member 500 is connected to the connecting rod 320 passing through the battery housing 200 and then abuts against the battery housing 200; the insulating assembly 600 is arranged between the negative current collector 300 and the battery housing 200. By restricting the sealing ring 400 between the first convex ring 311 and the second convex ring 312 on the disk body 310 of the negative current collector 300, the sealing ring 400 is not easily displaced during battery assembly, and the sealing effect is more guaranteed than that of a sealing ring without positioning.

[0043] In some embodiments disclosed in the present application, the sealing ring 400 is an elastic member.

[0044] In some embodiments disclosed in the present application, the insulating assembly 600 is an elastic member.

[0045] In some embodiments disclosed in the present application, the insulating assembly 600 includes a first insulator 610, a second insulator 620, and a third insulator 630; the first insulator 610 is disposed between the disk body 310 and the battery housing 200 for insulating and isolating the disk body 310 and the battery housing 200; the second insulator 620 is disposed between the first convex ring 311 and the battery housing 200 for insulating and isolating the first convex ring 311 and the battery housing 200; the third insulator is disposed between the connecting rod 320 and the battery housing 200 for insulating and isolating the connecting rod 320 and the battery housing 200. The above-mentioned insulating assembly 600 insulates and isolates the battery cell, the negative electrode assembly, and the battery housing 200 to avoid short circuit, and the above-mentioned insulating assembly 600 is made of an elastic insulating material. The first insulator 610, the second insulator 620, the third insulator 630, and the sealing ring 400 cooperate with each other and are in contact with each other, further improving the sealing effect at the negative electrode end of the battery cell.

[0046] In some embodiments disclosed in the present application, the disk body 310 and the connecting rod 320 are welded. The disk body 310 and the connecting rod 320 are connected by welding, and the appropriate sizes of the disk body 310 and the connecting rod 320 can be selected according to the size specifications of the battery to match the inner diameter of the battery housing 200 and the size of the through hole on the bottom surface of the housing.

[0047] In some other embodiments disclosed in the present application, the disk body 310 and the connecting rod 320 are integrally formed. The negative current collector 300 formed by the integrally formed disk body 310 and the connecting rod 320 has good electrical conductivity and reduces the internal resistance of the battery.

[0048] In some embodiments disclosed in the present application, the heights of both the first convex ring 311 and the second convex ring 312 are less than the thickness of the sealing ring 400. In this embodiment, it is ensured that the sealing ring 400 realizes the sealing at the negative electrode end of the battery cell when it is deformed under force.

[0049] In some embodiments disclosed in the present application, the height of the first convex ring 311 is not less than the height of the second convex ring 312. In this embodiment, the height of the first convex ring 311 at the outer edge is not less than the height of the second convex ring 312 at the inner ring, so that the sealing ring 400 is enclosed by the first convex ring 311 and will not move when deformed under pressure.

[0050] In some embodiments disclosed in the present application, the connecting rod 320 has an external thread; the fixing member 500 is a nut, and the nut is threadedly connected to the connecting rod 320. In this embodiment, the threaded connection between the nut and the connecting rod 320 makes the assembly of the negative electrode more convenient, and the external thread provided on the connecting rod 320 enables the nut to perform torque locking on the negative electrode assembly, resulting in better sealing performance.

[0051] When assembling a battery using the battery negative electrode assembly provided by the present application, the specific process is as follows: The negative electrode 100 of the battery cell is connected to the upper side of the disk body 310 of the negative current collector 300. The upper side of the disk body 310 can be fixedly connected to the negative electrode 100 of the battery cell by laser welding. Place the lower side of the disk body 310 facing upward, fit the first insulator 610 on the lower side of the disk body 310, place the sealing ring 400 between the first convex ring 311 and the second convex ring 312 on the lower side of the disk body 310, place the second insulator 620 on the first convex ring 311, and then fit the battery housing 200 on the battery cell with the above components installed, so that the connecting rod 320 of the negative current collector 300 passes through the through hole on the bottom surface of the end of the battery housing 200 and leads out the negative electrode of the battery. Then, set the third insulator 630 between the connecting rod 320 and the battery housing 200 for insulating and isolating the connecting rod 320 and the battery housing 200. The connecting rod 320 has an external thread. Screw the fixing member 500, the nut, onto the connecting rod 320 until the nut presses against the third insulator 630 and abuts against the battery housing 200. During the process of tightening the nut and the connecting rod 320, the sealing ring deforms under force to achieve the sealing of the negative electrode end of the battery cell, and further realizes the fixed connection between the battery cell and the battery housing.

[0052] The above has introduced in detail a battery negative electrode assembly provided by the present application. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the core idea of the present application. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present application, several improvements and modifications can still be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A battery negative electrode assembly, the negative electrode assembly being located between a battery cell negative electrode (100) and a battery housing (200) for leading out the battery negative electrode, characterized in that: It comprises a negative current collector (300), a sealing ring (400), a fixing member (500) and an insulating component (600); The negative current collector (300) comprises a disk body (310) and a connecting rod (320); the upper side of the disk body (310) is connected to the negative electrode (100) of the battery cell, and the center of the lower side of the disk body (310) is fixedly connected to the connecting rod (320); A first convex ring (311) and a second convex ring (312) are provided on the lower side of the disk body (310); the first convex ring (311) and the second convex ring (312) are sequentially arranged around the connecting rod (320) in concentric circles; The sealing ring (400) is disposed between the first convex ring (311) and the second convex ring (312); The fixing member (500) is connected to a connecting rod (320) passing through the battery housing (200) and then abuts against the battery housing (200); The insulating component (600) is disposed between the negative current collector (300) and the battery housing (200).

2. The battery negative electrode assembly according to claim 1, characterized in that: The insulating assembly (600) comprises a first insulator (610), a second insulator (620) and a third insulator (630); The first insulator is located between the disk (310) and the battery housing (200) to insulate and isolate the disk (310) and the battery housing (200); The second insulator (620) is arranged between the first convex ring (311) and the battery housing (200) to insulate and isolate the first convex ring (311) and the battery housing (200); The third insulator is disposed between the connecting rod (320) and the battery housing (200) to insulate and isolate the connecting rod (320) and the battery housing (200).

3. The battery negative electrode assembly according to claim 1, characterized in that: The disk body (310) and the connecting rod (320) are integrally formed.

4. The battery negative electrode assembly according to claim 1, characterized in that: The disk body (310) and the connecting rod (320) are welded.

5. The battery negative electrode assembly according to claim 1, characterized in that: The connecting rod (320) has an external thread; the fixing member (500) is a nut, and the nut is threadedly connected to the connecting rod (320).

6. The battery negative electrode assembly according to claim 1, characterized in that: The heights of the first convex ring (311) and the second convex ring (312) are both smaller than the thickness of the sealing ring (400).

7. The battery negative electrode assembly according to claim 1, characterized in that: The height of the first convex ring (311) is not less than the height of the second convex ring (312).

8. The battery negative electrode assembly according to claim 1, characterized in that: The sealing ring (400) is an elastic member.

9. The battery negative electrode assembly according to claim 1, characterized in that: The insulating component (600) is an elastic member.

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