A split battery tab

Abstract

The utility model relates to a kind of separate battery connecting piece, for electrically connecting battery cell and cover plate, it includes first conductive section, second conductive section and the intermediate fuse layer connecting both, wherein, at least one of first conductive section and second conductive section has elastic deformation structure, in installation state, keep pre-press bending mode;The intermediate fuse layer is connected first conductive section and second conductive section respectively by metallurgical bonding mode;When battery connecting piece is heated and fused, the first conductive section or second conductive section of pre-press bending mode rebounds, for making the pre-press first conductive section and the second conductive section separate, disconnect the electrical connection between the battery cell and cover plate.This application not only can guarantee the normal work of connecting piece, realize good thermal management, but also can be fused quickly when short-circuit fault, reliably and stably realize fuse protection.

Description

Technical Field

[0001] This utility model relates to a detachable battery connector. Background Technology

[0002] With the rapid development of new energy vehicles and energy storage equipment, the safety performance requirements of battery modules are becoming increasingly stringent. As a key component for current transmission within the module, the battery connector is used to connect the cell tabs to the battery cover; its overcurrent protection capability directly affects system safety.

[0003] Traditional integrated metal connectors typically achieve short-circuit protection through a melting mechanism, relying on highly conductive metals (such as copper and aluminum) with high melting points (copper 1083°C, aluminum 660°C). When the battery experiences overcurrent or a short circuit, heat accumulates slowly and cannot melt in time before thermal runaway (usually requiring several seconds to tens of seconds), causing the internal temperature of the battery to rise sharply, leading to fire or explosion.

[0004] To address the aforementioned issues, certain measures have been taken to resolve them. Currently, a common method is to create a 6-inch opening (called a fuse) on the connecting piece, such as... Figure 1 As shown, the opening reduces the current-carrying capacity of the open area. When an overcurrent or short circuit occurs, the open area heats up faster than the conventional area, which helps to melt the fuse in time before thermal runaway. However, this structure introduces a new problem: if the current-carrying area of ​​the fuse region is designed to be too small, the fuse region will heat up severely during normal use, affecting the thermal management of the cell and potentially causing it to melt before a safety fault occurs; if the current-carrying area of ​​the fuse region is designed to be too large, the fuse region will take a long time to melt, failing to meet safety requirements.

[0005] Therefore, how to optimize the structure of the battery connector to overcome the defects of traditional connectors is the technical problem that this application aims to solve. Utility Model Content

[0006] One of the main objectives of this invention is to overcome at least one of the aforementioned defects by providing a detachable battery connector that not only ensures the normal operation of the connector and achieves good thermal management, but also allows for rapid melting and reliable and stable protection in the event of a short circuit.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0008] This utility model provides a detachable battery connector for electrically connecting a battery cell and a cover plate. It includes a first conductive segment, a second conductive segment, and an intermediate fused layer connecting the two.

[0009] At least one of the first conductive segment and the second conductive segment has an elastic deformation structure, which maintains a pre-compression bending shape in the installed state.

[0010] The intermediate fracturing layer connects the first conductive segment and the second conductive segment respectively by metallurgical bonding.

[0011] When the battery connector is heated and melted, the first or second conductive segment, which is in a pre-compressed and bent state, springs back, which is used to separate the first conductive segment from the second conductive segment and disconnect the electrical connection between the battery cell and the cover plate.

[0012] According to one embodiment of the present invention, the first conductive segment is rectangular, one side of the second conductive segment is in contact with the surface of the second conductive segment, and the intermediate fusing layer is disposed at the contact surface between the first conductive segment and the second conductive segment.

[0013] According to one embodiment of the present invention, the cross-sectional area of ​​the intermediate fusion layer is not less than 50% and not more than 75% of the contact surface area.

[0014] According to one embodiment of the present invention, the second conductive segment is U-shaped or L-shaped, and one side of the first conductive segment is connected to the surface of the second conductive segment.

[0015] According to one embodiment of the present invention, the contact surfaces of the first conductive segment and the second conductive segment are provided with an interlocking structure. The interlocking structure includes, but is not limited to, at least one of a serrated interlocking surface and a concave-convex interlocking structure. The intermediate fusion layer is disposed in the interlocking structure.

[0016] According to one embodiment of the present invention, the bending angle of the pre-compression bending form is 15°~60°, and the bending direction is towards the side where the intermediate fusion layer is located.

[0017] According to one embodiment of the present invention, the elastic modulus of the first conductive segment or the second conductive segment is not less than 100 GPa.

[0018] According to one embodiment of the present invention, the first conductive segment or the second conductive segment having an elastic deformation structure is made of 3J21 alloy or 3J01 alloy.

[0019] According to one embodiment of the present invention, the intermediate fracturing layer is made of a metal material with a melting point lower than that of the first conductive segment and the second conductive segment. The material used for the intermediate fracturing layer is any one of Zn, Pb, Sn and Cr, or an alloy composed of two or more of them.

[0020] According to one embodiment of the present invention, one of the first conductive segment and the second conductive segment is made of any one of Al, Cu, Ni and Ti, or an alloy composed of two or more of them.

[0021] Compared with the prior art, the advantages and beneficial effects of the detachable battery connector in this utility model patent application are as follows:

[0022] In the detachable battery connector of this application, the first conductive segment and / or the second conductive segment maintain a pre-compression bent shape during installation, with the bending direction facing the intermediate fusion layer. The intermediate fusion layer connects the two conductive segments through a metallurgical bonding method (such as welding or brazing). When overcurrent causes the intermediate fusion layer to melt, the pre-compression bent portion of the conductive segment rebounds due to elasticity, driving the two conductive segments to separate, thus achieving rapid disconnection of the electrical connection. This structure has the following advantages:

[0023] 1. Fast response speed: The elastic rebound is triggered when the fuse layer melts locally, avoiding large-area heat diffusion;

[0024] 2. Simplified structure: No additional mechanical triggering mechanism is required, reducing space occupation and manufacturing costs;

[0025] 3. High reliability: The pre-compression bending angle is matched with the melting area to ensure that the separation action is triggered instantly upon melting;

[0026] 4. Good operational stability: When the current flowing through the battery connector is normal, the connector heats up normally, ensuring good thermal management of the battery cell. Attached Figure Description

[0027] The following sections will describe some specific embodiments of the present invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or components. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0028] Figure 1 This is a structural diagram of a battery connector based on existing technology;

[0029] Figure 2 This is a schematic diagram of the structure of a detachable battery connector according to an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of a detachable battery connector according to another embodiment of the present invention;

[0031] Figure 4-1 This is a side view of the detachable battery connector in the installation state according to an embodiment of the present invention;

[0032] Figure 4-2This is a side view of the detachable battery connector in the installed state according to an embodiment of the present invention;

[0033] Figure 4-3 This is a side view of the detachable battery connector after thermal melting and disconnection according to an embodiment of the present invention.

[0034] The annotations in the attached figures are explained as follows:

[0035] 1. First conductive segment; 11. Elastic deformation structure of the first conductive segment; 2. Second conductive segment; 21. Warping of the second conductive segment; 3. Intermediate fusion layer; 4. Cover plate; 5. Battery cell.

[0036] 6. The opening in the existing connector, i.e., the fuse. Detailed Implementation

[0037] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0038] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0039] This embodiment describes a detachable battery connector for electrically connecting the battery cell 5 and the cover plate 4, such as... Figure 2 As shown, it generally includes a first conductive segment 1, a second conductive segment 2, and an intermediate fusion layer 3 connecting the two, wherein,

[0040] The first conductive segment 1 has an elastic deformation structure 11, which maintains a pre-compression bending shape in the installation state;

[0041] The intermediate fracturing layer 3 is connected to the first conductive segment 1 and the second conductive segment 2 by a metallurgical bonding method.

[0042] The first conductive segment 1 is connected to the cover plate 4, and the second conductive segment 2 is connected to the tab of the battery cell 5;

[0043] The first conductive segment 1 is rectangular, the second conductive segment 2 is U-shaped or L-shaped, one side of the second conductive segment 2 is in contact with the surface of the second conductive segment 2, and the intermediate fusing layer 3 is disposed at the contact surface between the first conductive segment 1 and the second conductive segment 2.

[0044] When the battery connecting piece is heated and melted, the first conductive segment 1 or the second conductive segment 2, which is in a pre-compressed bent state, springs back, which is used to separate the first conductive segment 1 from the second conductive segment 2 and disconnect the electrical connection between the battery cell 5 and the cover plate 4.

[0045] The first conductive segment 1 with elastic deformation structure is made of 3J21 alloy or 3J01 alloy; the second conductive segment 2 is made of any one of Al, Cu, Ni and Ti, or an alloy composed of two or more of them.

[0046] It is understood that in the detachable battery connector of this embodiment, the first conductive segment 1 maintains a pre-compression bent shape during installation, with the bending direction facing the intermediate fusion layer 3. The intermediate fusion layer 3 connects the two conductive segments through metallurgical bonding methods (such as welding or brazing). When the intermediate fusion layer 3 melts due to overcurrent, the pre-compression bent part in the first conductive segment 1 rebounds due to elasticity. The second conductive segment 2 has less elasticity than the first conductive segment 1, but due to the properties of metal, it can maintain its basic shape.

[0047] As an optimization, to facilitate the connection and fixation between the first conductive segment 1 and the second conductive segment 2, such as... Figure 3 As shown, the end of the second conductive segment 2 (the end that connects with the first conductive segment 1) has a protrusion 21 facing the first conductive segment 1. When the end of the first conductive segment 1 is pre-pressed and bent, it can contact the protrusion 21 of the second conductive segment 2. The connection is then metallurgically bonded by the intermediate fusing layer 3, which can conveniently realize the fixed connection and conductive connection between the first conductive segment 1, the intermediate fusing layer 3, and the second conductive segment 2.

[0048] Alternatively, the second conductive segment 2 can be designed to maintain a pre-compression bent shape during installation, with the bending direction towards the middle fusion layer 3. The second conductive segment 2 can be made of 3J21 alloy or 3J01 alloy with high elastic strength, while the first conductive segment 1 does not have an elastic deformation structure. When the connecting piece melts, the second conductive segment 2 rebounds, causing the two conductive segments to separate. Alternatively, both the first conductive segment 1 and the second conductive segment 2 can be designed with elastic deformation structures, and at the joint ends, the two conductive segments can approach each other and be pre-compressed towards the middle contact area. This allows the first conductive segment 1 and the second conductive segment 2 to separate more quickly when the connecting piece melts. The specific configuration can be adjusted according to user needs or safety parameters.

[0049] However, it should be noted that in order to ensure sufficient rebound force, the elastic modulus of the first conductive segment 1 or the second conductive segment 2 with elastic deformation should not be less than 100 GPa. Furthermore, the bending angle of the pre-compression bending form is 15°~60°, and the bending direction is towards the side where the intermediate fusion layer 3 is located.

[0050] Furthermore, the step of fixing the first conductive segment 1 and the second conductive segment 2 through the intermediate fusing layer 3 can be completed during the manufacturing of the connecting piece at the factory, or it can be completed during battery assembly and then assembled and fixed with the battery cell 5 and the cover plate 4. Alternatively, the first conductive segment 1 can be fixed to the cover plate 4, and the second conductive segment 2 can be fixed to the battery cell 5, and then the first conductive segment 1 and the second conductive segment 2 can be connected and fixed by adding the intermediate fusing layer 3 through metallurgical bonding methods (such as welding or brazing). In short, there are various assembly methods. However, it is important to note that after installation, the elastic deformation structure of the first conductive segment 1 must be pre-compressed and bent. That is, as mentioned above, the elastically deformable first conductive segment 1 must maintain a pre-compressed and bent shape in the installed state. Only in this way can it achieve the effect of overcurrent protection after installation.

[0051] It is understandable that the connection status of the battery connecting pieces before assembly into the battery cell 5 and cover plate 4, i.e., the state before installation, is as follows: Figure 4-1 As shown; after assembly of the battery cell 5 and cover plate 4, that is, the connection status of the battery connecting pieces in the installed state is as follows. Figure 4-2 As shown, the first conductive segment 1 is fixedly connected to the cover plate 4, and the second conductive segment 2 is fixedly connected to the battery cell 5. The first conductive segment 1 is in a pre-compression bent state, that is, the end of the first conductive segment 1 (the end connected to the second conductive segment 2) bends towards the middle fusion layer 3, or in other words, the direction of the second conductive segment 2. When an overload occurs in the current passing through the battery connecting piece (e.g., a short circuit fault), the middle fusion layer 3 begins to melt, and the pre-compression bent part in the first conductive segment 1 rebounds due to its elasticity, driving the first conductive segment 1 and the second conductive segment 2 to quickly separate, achieving a rapid disconnection of the electrical connection. The final state after disconnection is as follows. Figure 4-3 As shown.

[0052] In order to ensure the connection strength between the first conductive segment 1 and the second conductive segment 2 in the connecting piece, and at the same time to ensure that the first conductive segment 1 and the second conductive segment 2 can be effectively separated when the fault such as short circuit causes overcurrent, the cross-sectional area of ​​the intermediate fusion layer 3 is not less than 50% of the contact surface area, but not more than 75% of the contact surface area.

[0053] In one embodiment, the contact surfaces of the first conductive segment 1 and the second conductive segment 2 are provided with an interlocking structure. The interlocking structure includes, but is not limited to, at least one of a serrated interlocking surface and a concave-convex interlocking structure. The intermediate fusion layer 3 is disposed in the interlocking structure.

[0054] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the protection scope of this utility model.

Claims

1. A detachable battery connector for electrically connecting a battery cell and a cover plate, characterized in that, It includes a first conductive segment, a second conductive segment, and an intermediate fusible layer connecting the two, wherein, At least one of the first conductive segment and the second conductive segment has an elastic deformation structure, which maintains a pre-compression bending shape in the installed state. The intermediate fracturing layer connects the first conductive segment and the second conductive segment respectively by metallurgical bonding. When the battery connector is heated and melted, the first or second conductive segment, which is in a pre-compressed and bent state, springs back, which is used to separate the first conductive segment from the second conductive segment and disconnect the electrical connection between the battery cell and the cover plate.

2. The detachable battery connector according to claim 1, characterized in that, The first conductive segment is rectangular, one side of the second conductive segment is in contact with the surface of the second conductive segment, and the intermediate fusing layer is disposed at the contact surface between the first conductive segment and the second conductive segment.

3. The detachable battery connector according to claim 2, characterized in that, The cross-sectional area of ​​the intermediate fusion layer is not less than 50% and not more than 75% of the contact surface area.

4. The detachable battery connector according to claim 1, characterized in that, The second conductive segment is U-shaped or L-shaped, and one side of the first conductive segment is connected to the surface of the second conductive segment.

5. The detachable battery connector according to any one of claims 2 to 4, characterized in that, The contact surfaces of the first conductive segment and the second conductive segment are provided with an interlocking structure. The interlocking structure includes, but is not limited to, at least one of a serrated interlocking surface and a concave-convex interlocking structure. The intermediate fusion layer is disposed in the interlocking structure.

6. The detachable battery connector according to claim 1, characterized in that, The bending angle of the pre-compression bending form is 15°~60°, and the bending direction is towards the side where the intermediate fusion layer is located.

7. The detachable battery connector according to claim 1, characterized in that, The elastic modulus of the first conductive segment or the second conductive segment is not less than 100 GPa.

8. The detachable battery connector according to claim 7, characterized in that, The first or second conductive segment with an elastic deformation structure is made of 3J21 alloy or 3J01 alloy.

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