New connector assembly and battery

Abstract

This utility model belongs to the field of lithium-ion battery technology, specifically relating to a battery connector assembly, including a cover plate body, a terminal base plate, and a connector. The terminal base plate is disposed on the cover plate body. The connector includes a terminal connection portion, a tab connection portion, and a fusible portion located between the terminal connection portion and the tab connection portion. It also includes an insulating overlay block and an insulating coating. The insulating overlay block is fitted into the fusible portion, and the outer surface of the insulating overlay block is flush with the surface of the connector. The insulating coating covers the terminal connection portion and reserves an area for laser welding. This utility model, by innovatively setting an insulating coating on the terminal connection portion of the connector, effectively solves the problem of fusible failure caused by direct overlap of the terminal connection portion due to excessively long or misaligned tabs.

Description

Technical Field

[0001] This utility model belongs to the field of lithium-ion battery technology, specifically relating to a novel connector assembly and battery. Background Technology

[0002] With the rapid development of the new energy vehicle industry, lithium-ion batteries, as their core power source, have attracted much attention regarding their safety, energy density, and structural reliability. Especially in high-capacity, high-power applications such as electric vehicles and energy storage systems, the working environment of individual battery cells is becoming increasingly complex, placing higher demands on the battery's ability to protect against abnormal conditions such as overcharging and short circuits.

[0003] Inside a lithium battery, the tabs are electrically connected to the terminals on the cover plate via connecting tabs. To promptly disconnect the circuit in case of overcharging or short circuits, and to prevent thermal runaway leading to combustion or explosion, a fuse is usually installed in the middle of the connecting tab. This fuse melts rapidly when excessive current passes through, thereby achieving electrical isolation between the tab and the terminal, and providing safety protection.

[0004] To prevent the tabs from accidentally overlapping with the fuse or pole connection area during assembly or use, thus affecting the reliability of the fuse function, existing technologies often embed insulating rubber blocks around the fuse for local isolation. However, this method has the following obvious drawbacks:

[0005] Insulating rubber blocks occupy space: Traditional insulating rubber blocks usually protrude from the surface of the connecting piece, occupying valuable internal space in the height direction of the battery, which limits the improvement of cell energy density and is not conducive to battery miniaturization and lightweight design;

[0006] Risk of tab misalignment: As battery rate performance requirements increase, the tab area and length may also increase accordingly. In cases of tab misalignment or positioning deviation, excessively long tabs may extend beyond the coverage area of ​​the insulating rubber block and directly contact the terminal connection, forming a parallel current path. This can cause the fuse to fail to effectively melt during overcurrent, resulting in loss of safety protection function and posing a serious safety hazard.

[0007] Several improvements have been made in the prior art, such as using larger insulating sheets to cover both sides of the fused section (e.g., CN201920107707.0), or using an integrally molded insulating component to simultaneously wrap the fused section and part of the connection area (e.g., CN202280027235.2), and there are also solutions that use insulating reinforcement components for structural positioning (e.g., CN202320151345.1). However, these solutions either fail to effectively solve the problem of the insulating components occupying space, or fail to completely eliminate the risk of misalignment and overlap of the electrodes, and there is still room for improvement in terms of space utilization and safety reliability.

[0008] Therefore, there is an urgent need for a new type of battery connector assembly structure that can optimize the spatial layout, improve the space utilization and overall safety of the battery, while ensuring the reliability of the fuse protection function. Utility Model Content

[0009] The purpose of this patent is to provide a novel connector assembly and battery. By providing an insulating coating at the connection point with the terminal post to prevent misalignment of the terminals, and by making the insulating rubber block covering the fused portion flush with the surface of the connector, the battery safety is improved while increasing space utilization.

[0010] To achieve the above objectives, this utility model provides the following technical solution:

[0011] This utility model provides a battery connector assembly, including a cover plate body, a terminal base plate, and a connector. The terminal base plate is disposed on the cover plate body. The connector includes a terminal connection portion, a terminal tab connection portion, and a fusion break portion located between the terminal connection portion and the terminal tab connection portion. It also includes an insulating rubber block and an insulating coating. The insulating rubber block is fitted with the fusion break portion, and the outer surface of the insulating rubber block is flush with the surface of the connector. The insulating coating covers the terminal connection portion and reserves an area for laser welding.

[0012] Preferably, the fused portion is a partially thinned structure in the middle region of the connecting piece.

[0013] Preferably, the two sides of the fused portion are recessed downward into the connecting piece.

[0014] Preferably, the thickness of the insulating rubber-coated block protruding from the surface of the connecting piece ranges from 0 to 300 μm.

[0015] Preferably, the insulating coating is formed by plasma spraying.

[0016] Preferably, the thickness of the insulating coating is 50 μm to 200 μm.

[0017] Preferably, the insulating coating has insulating and flame-retardant properties.

[0018] Preferably, the insulating coating comprises silica powder, alumina, chlorinated polyimide ether, modified halogen-free flame retardant filler, and a resin composition.

[0019] Preferably, the resin composition is one of epoxy resin, silicone resin, phenolic resin, and ethylene copolymer resin.

[0020] This utility model also discloses a battery, including the aforementioned battery connector assembly.

[0021] The beneficial effects of this utility model are as follows: By innovatively setting an insulating coating on the terminal connection part of the connecting piece, this utility model effectively solves the problem of fusible link failure caused by the direct overlap of the terminal connection part due to excessively long or misaligned tabs. This insulating coating acts as a reliable insulating barrier, ensuring that current must flow through the fusible link. Therefore, in abnormal situations such as battery overcharging or short circuits, the fusible link can accurately and quickly melt, forming a safe circuit break, significantly improving the safety and reliability of the battery cell.

[0022] Meanwhile, this invention optimizes the structure and assembly method of the insulating rubber block, making it flush with the fused portion on the surface of the connecting piece, and flush with the outer surface of the connecting piece, thus avoiding the space occupation of the battery's internal space by the traditional protruding design. This design significantly reduces the space requirement of the connecting piece assembly in the height direction of the battery, improves the space utilization and energy density of the cell, and provides favorable conditions for the miniaturization and lightweight design of the battery. Attached Figure Description

[0023] Figure 1 A perspective view of a single battery cell is provided for this utility model;

[0024] Figure 2 for Figure 1 Side sectional view;

[0025] Figure 3 for Figure 2 A magnified view of the internal connection at point A shown in the diagram;

[0026] Figure 4 This is a schematic diagram showing the connection between the cover plate and the connecting piece assembly;

[0027] Figure 5 for Figure 4 A schematic diagram of the connecting piece assembly shown;

[0028] Figure 6 This is an exploded view of the component of this utility model;

[0029] The attached diagram is described below:

[0030] The attached diagram is described below:

[0031] 1. Cover plate body; 11. Pole post base plate; 2. Connecting piece assembly; 21. Connecting piece; 22. Insulating rubber block; 23. Insulating coating; 211. Pole post connecting part; 212. Pole ear connecting part; 213. Fusible part; 3. Pole group; 31. Pole group body; 32. Pole ear. Detailed Implementation

[0032] It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0033] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0034] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixed connection," and "fixed connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0035] The specific embodiments of this utility model are described in detail below with reference to the accompanying drawings and preferred embodiments.

[0036] like Figure 1 The diagram shown is a schematic of a battery cell according to an embodiment of the present invention. The square ternary lithium battery described in this embodiment is formed by laser welding of a cover plate body 1 and a battery casing 4 to the outside of the battery cell.

[0037] like Figures 2-6 As shown. In the embodiments of this application, the connecting piece assembly 2 includes a connecting piece 21, an insulating rubber block 22, and an insulating coating 23. The connecting piece 21 includes a terminal post connecting portion 211, a tab connecting portion 212, and a fusible portion 213. The fusible portion 213 connects the terminal post connecting portion 211 and the tab connecting portion 212. The electrode group 3 includes an electrode group body 31 and a tab 32. The tab 32 is connected to the tab connecting portion 212 by ultrasonic welding. The terminal post connecting portion 211 is connected to the terminal post base plate 11 by laser welding, thereby connecting the electrode group 3 to the cover plate body 1, so that the current generated by the battery can be transmitted to the terminal post through the tab 32 and the connecting piece 21.

[0038] The fuse section 213 is characterized by a localized thinning in the middle area of ​​the connecting piece 21 and recesses on both sides into the connecting piece 21. When the battery is abnormally overcharged, the large current generated by the short circuit will cause the fuse section 213 to melt, disconnecting the terminal connection 211 and the tab connection 212, thereby blocking the connection between the tab 32 and the terminal. The internal circuit of the battery changes from a short circuit to an open circuit, preventing the accumulation of more heat and thus avoiding explosion and fire, ensuring the safety of the battery. The insulating rubber block 22 is flatly embedded with the fuse section 213, wrapping around the fuse section 213. When the fuse section 213 melts, it plays a role in wrapping and supporting, preventing the tab 32 from overlapping with the terminal connection 211 after the circuit is broken, which could endanger the safety of the battery cell. At the same time, the shape of the insulating rubber block 22 is flush with the surface of the connecting piece 21 and does not protrude outward, thus avoiding the space waste caused by the traditional externally embedded insulating rubber block 22 protruding from the connecting piece 21 and its own thickness occupying battery cell space.

[0039] The insulating coating 23 has insulating and flame-retardant properties. It covers the electrode connection 211 in the form of plasma spraying, avoiding the embossed area required for laser welding. The insulating coating 23 is seamlessly connected to the insulating rubber block 22. Generally, the larger the area of ​​the tab 32, the better its heat dissipation performance. For high-rate, high-capacity cells, a large area of ​​tab 32 is required. When the height of the tab 32 is limited, the tab 32 is lengthened. However, the existence of a longer tab 32 and the existence of staggered tabs 32 will cause the tab 32 to bypass the insulating rubber block 22 and directly connect to the electrode connection 211, thereby dispersing the current path. The current cannot pass through the fuse 213 completely, causing the fuse 213 to fail. Therefore, the terminal connection 211 needs to be covered with an insulating coating 23. Even if the length of the tab 32 extends beyond the insulating rubber block 22, the tab 32 will only contact the insulating coating 23. The tab 32 and the terminal connection 211 will not make direct contact, thereby avoiding the failure of the fuse 213 and improving the safety of the battery cell.

[0040] For those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model.

Claims

1. A battery tab assembly, characterized by: The device includes a cover plate body (1), a pole base plate (11), and a connecting piece assembly (2). The connecting piece assembly includes a connecting piece (21), an insulating rubber block (22), and an insulating coating (23). The pole base plate (11) is disposed on the cover plate body (1). The connecting piece (21) includes a pole connecting part (211), a pole tab connecting part (212), and a fusion part (213) located between the pole connecting part (211) and the pole tab connecting part (212). The insulating rubber block (22) is fitted with the fusion part (213), and the outer surface of the insulating rubber block (22) is flush with the surface of the connecting piece (21). The insulating coating (23) covers the pole connecting part (211) and reserves an area for laser welding.

2. The battery tab assembly of claim 1, wherein, The fused portion (213) is a partially thinned structure in the middle region of the connecting piece (21).

3. The battery tab assembly of claim 2, wherein, The two sides of the fuse portion (213) are recessed downward into the connecting piece (21).

4. The battery tab assembly of claim 1, wherein, The thickness of the insulating rubber-coated block (22) protruding from the surface of the connecting piece (21) ranges from 0 to 300 μm.

5. The battery tab assembly of claim 1, wherein, The insulating coating (23) is formed by plasma spraying.

6. The battery tab assembly of claim 1 or 5, wherein, The thickness of the insulating coating (23) is 50μm to 200μm.

7. The battery tab assembly of claim 1, wherein, The insulating coating (23) has insulating and flame-retardant properties.

8. The battery connector assembly according to claim 7, characterized in that, The insulating coating (23) comprises silica powder, alumina, chlorinated polyimide ether, modified halogen-free flame retardant filler and resin composition.

9. The battery tab assembly of claim 8, wherein, The resin composition is one of epoxy resin, silicone resin, phenolic resin, and ethylene copolymer resin.

10. A battery, characterized by Includes the battery connector assembly as described in any one of claims 1 to 9.

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