Bending type lithium battery connecting piece, cover plate and lithium battery

Abstract

The utility model discloses a bending type lithium battery connecting piece, a cover plate and a lithium battery, and belongs to the technical field of lithium batteries, the bending type lithium battery connecting piece comprises a first welding part, a second welding part and a third welding part, the first welding part is used for welding a pole column, and the second welding part and the third welding part are used for welding a battery cell tab; the second welding part and the third welding part are respectively connected with the first welding part through the bending parts, and the first welding part, the second welding part and the third welding part are positioned on different planes through the bending parts; the bent part is provided with a clearance, and gaps are formed between the first welding part and the second welding part and between the first welding part and the third welding part through the clearance. According to the utility model, the tabs of the battery cell can be avoided through the clearance, so that the tabs are prevented from being lapped to the convex hulls of the bent parts of the connecting pieces to influence normal welding.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, specifically to a bent lithium battery connector, a cover plate, and a lithium battery. Background Technology

[0002] Lithium-ion battery connectors are conductive pieces used to connect the positive and negative electrodes in a lithium-ion battery. Their main function is to facilitate current transmission and control the charging and discharging of the battery. A lithium-ion battery generally consists of a top cover, a cell, and connectors. The tabs of the cell are first connected to the connectors via ultrasonic welding, and then the connectors are laser-welded to the terminals of the top cover assembly, thus connecting the cell to the top cover.

[0003] Typically, the connecting piece is welded to the top cover terminal inside the power battery. The connecting piece structure is usually a butterfly clip structure or a flat plate structure. The disadvantage of this structure is that the connecting piece and the terminal occupy the internal space of the cell after welding, and the internal space of the cell cannot be fully utilized.

[0004] To improve the utilization of internal battery space, Chinese patent document CN210837817U discloses a power battery top cover, adapter piece, and power battery. The adapter piece, or connecting piece, includes a first welding portion in the shape of a boss, used for welding to a first electrode post. The first welding portion extends outward to form a second welding portion and a third welding portion, used for connecting to the cell tabs. A first bend and a second bend are respectively provided between the first and second welding portions and the third welding portion to increase the strength of the connecting piece and reduce the occupation of internal battery space. However, the presence of the bends may cause the cell tabs to overlap with the protruding part of the bend, affecting the normal welding of the tabs to the welding portions. Utility Model Content

[0005] The purpose of this utility model is to provide a bent lithium battery connector, cover plate and lithium battery, to solve the problem that the presence of the bend in the lithium battery connector in the prior art may cause the cell tab to overlap with the protruding part of the bend, affecting the normal welding of the tab and the welding part.

[0006] To achieve the above objectives, this utility model provides a bent lithium battery connector, comprising a first welding portion, a second welding portion, and a third welding portion. The first welding portion is used for welding the terminal post, and the second and third welding portions are used for welding the battery cell tabs. The second and third welding portions are respectively connected to the first welding portion through a bending portion, and the first welding portion is located on different planes from the second and third welding portions through the bending portion. The bending portion is provided with a clearance, which creates gaps between the first welding portion and the second and third welding portions, respectively.

[0007] Furthermore, the second and third welded portions extend away from the center of the first welded portion, while the clearance extends closer to the center of the first welded portion.

[0008] The clearance extends closer to the center of the first weld section, further shortening the length of the bend, thereby improving the fusing efficiency of the connecting piece and enhancing its protective function when facing sudden short-circuit high currents.

[0009] Furthermore, the first welding portion includes a first welding surface and a second welding surface disposed opposite to each other, the second welding surface being disposed in the direction of the battery cell; the first welding surface is provided with a protrusion, and the second welding surface is provided with a groove at the position corresponding to the protrusion.

[0010] The protrusion is used for welding to the pole post, and it can also engage with the corresponding groove in the cover plate structure, facilitating the positioning and installation of the connecting piece. A groove is formed on the second welding surface corresponding to the protrusion through stamping. Stamping alters the structure of the connecting piece without increasing its weight, eliminating the need for additional components or materials to form the protrusion, thus conforming to lightweight design principles.

[0011] Furthermore, the protruding direction of the convex bulge of the bent portion is close to the second welding surface, and the second welding portion and the third welding portion are located on the side close to the first welding surface by being bent by the bent portion.

[0012] The first welding surface is used to connect with the terminal post and is closer to the cover plate structure. Therefore, the second and third welding parts are closer to the cover plate structure, which can leave more space for the cell direction, thereby improving the battery energy density.

[0013] Furthermore, the distance between the second and third welding parts and the second welding surface is 0.5mm to 1mm. The second and third welding parts can be raised 0.5mm to 1mm towards the first welding surface, which can make full use of the space under the cover plate structure. The inner angle of the bending angle of the bending part is 90°±10°. At this bending angle, the strength of the connecting piece can be guaranteed, while minimizing the space occupied by the connecting piece, further improving the energy density of the battery. Moreover, the bending angle within this range facilitates equipment stamping and forming.

[0014] Furthermore, the extensions of the second and third welding parts are arranged in parallel and there is a gap between them. The gap can provide more clearance space, ensuring that there is space to arrange other components after the connecting piece connects the battery cell tabs.

[0015] Furthermore, the ends of the extensions of both the second and third welding portions are provided with chamfered portions, which are arranged at intervals.

[0016] The chamfered portion serves two purposes: firstly, it acts as a foolproof design to prevent incorrect assembly of the connecting piece; secondly, it allows for further weight reduction of the connecting piece, thereby increasing the energy density of the battery.

[0017] This utility model also provides a cover plate, including a rivet, which is connected to the connecting piece mentioned above; the cover plate has a groove at the location of the rivet that matches the protrusion.

[0018] This utility model also provides a lithium battery, including the above-mentioned connecting piece or the above-mentioned cover plate.

[0019] Compared with existing known technologies, the technical solution provided by this utility model has the following beneficial effects:

[0020] This utility model discloses a bent lithium battery connector. The bent portion increases the structural strength of the connector. The first welding portion, through the bend, is on a different plane from the second and third welding portions, allowing the first welding portion to be closer to the electrode post. Simultaneously, it creates a spatial misalignment with the second and third welding portions, facilitating the placement of the cell tabs and saving internal battery space. The gaps between the first and second / third welding portions prevent the cell tabs from overlapping with the protrusions of the bent portion, thus avoiding interference with welding. Furthermore, the gaps reduce the size of the bend, thereby reducing the size of the connection area between the first and second / third welding portions, which can act as a fuse, providing a certain level of safety protection.

[0021] It is obvious that the elements or features described in the above individual embodiments can be used alone or in combination in other embodiments. Attached Figure Description

[0022] The dimensions and scales in the accompanying drawings do not represent the actual dimensions and scales of the product. The drawings are for illustrative purposes only, and some non-essential elements or features have been omitted for clarity.

[0023] Figure 1 This is a schematic diagram of the connecting piece in one embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram (II) of the connecting piece in an embodiment of this utility model;

[0025] Figure 3 This is a schematic diagram of the connecting piece projected from the second welding surface in an embodiment of this utility model;

[0026] Figure 4This is a schematic diagram of the cover plate structure in an embodiment of this utility model.

[0027] Explanation of reference numerals in the attached figures

[0028] 100, First welded part; 101, First welded surface; 102, Second welded surface; 110, Bending part; 120, Clearance; 130, Protrusion; 131, Groove; 200, Second welded part; 300, Third welded part; 400, Spacing; 500, Chamfer; 600, Rivet; 610, Groove. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the accompanying drawings. The embodiments described herein are merely preferred embodiments of the present invention. Those skilled in the art can conceive of other ways to implement the present invention based on the preferred embodiments, and such other ways also fall within the scope of the present invention.

[0030] Reference Figures 1-3 This application provides a bent lithium battery connector, including a first welding portion 100, a second welding portion 200, and a third welding portion 300. The first welding portion 100 is typically laser-welded to the electrode post, while the second welding portion 200 and the third welding portion 300 are ultrasonically welded to the cell tab. The cell tab and the electrode post transmit current outward through the connector. The second welding portion 200 and the third welding portion 300 are respectively connected to the first welding portion 100 through bending portions 110. The first welding portion 100, the second welding portion 200, and the third welding portion 300 are an integral structural design. The bending portion 110 is formed by stamping, which increases the structural strength of the connector. Furthermore, the first welding portion 100 is located on a different plane from the second welding portion 200 and the third welding portion 300 via the bending portion 110. This allows the first welding portion 100 to be closer to the terminal post, while simultaneously creating a spatial misalignment with the second welding portion 200 and the third welding portion 300. This facilitates the placement of the cell tabs and helps save internal battery space. Moreover, the bending portion 110 is provided with a clearance 120. The clearance 120 creates gaps between the first welding portion 100 and the second welding portion 200 and the third welding portion 300. On the one hand, the clearance 120 avoids the cell tabs, preventing them from overlapping the protrusion of the bending portion 110 of the connecting piece, which would affect normal welding. On the other hand, the presence of the clearance 120 reduces the size of the bending portion 110, thus reducing the size of the connection area between the first welding portion 100 and the second welding portion 200 and the third welding portion 300. This can act as a fuse, providing a certain level of safety protection.

[0031] Specifically, such as Figure 1 and Figure 3As shown, in some embodiments of this application, the first welding part 100 is a sheet-like structure with a straight edge on the left and an arc edge on the right. The front side is connected to the second welding part 200 via a bending part 110, and the rear side is connected to the third welding part 300 via a bending part 110. The second welding part 200 and the third welding part 300 are generally elongated sheet-like structures. The second welding part 200 and the third welding part 300 extend away from the center of the first welding part 100, while the clearance 120 extends closer to the center of the first welding part 100, further shortening the length of the bending part 110. This improves the fusing efficiency of the connecting piece in the face of sudden short-circuit high currents and enhances the protective function of the connecting piece.

[0032] It is understandable that, such as Figure 1 and Figure 2 As shown, the first welding portion 100 includes a first welding surface 101 and a second welding surface 102 disposed opposite to each other. The first welding surface 101 is disposed towards the direction of the electrode post, and the second welding surface 102 is disposed towards the direction of the battery cell. The first welding surface 101 is provided with a protrusion 130, which is welded to the electrode post. At the same time, the protrusion 130 can engage with the corresponding groove 610 of the cover plate structure, which facilitates the positioning and installation of the connecting piece. The second welding surface 102 is formed into a groove 131 corresponding to the position of the protrusion 130 by stamping. Stamping can change the structure of the connecting piece without increasing its weight, and there is no need to add additional parts or materials to form the protrusion 130, which conforms to the lightweight design concept.

[0033] In some embodiments of this application, the protrusion direction of the convex bulge of the bent portion 110 is close to the second welding surface 102. The second welding portion 200 and the third welding portion 300 are bent by the bent portion 110 and located on the side close to the first welding surface 101. The first welding surface 101 is used to connect with the electrode post and is closer to the cover plate structure. Therefore, when the second welding portion 200 and the third welding portion 300 are closer to the side of the first welding surface 101, that is, closer to the cover plate structure, more space can be left for the position in the cell direction, thereby improving the battery energy density. The distance between the second welding portion 200 and the third welding portion 300 and the second welding surface 102 is 0.5mm to 1mm, preferably 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm and 1mm. When the distance is 1mm, that is, the second welding portion 200 and the third welding portion 300 are raised 1mm towards the first welding surface 101, the space under the cover plate structure can be fully utilized. The inner angle of the bending angle of the bending section 110 is 90°±10°, specifically, it can be 80°, 85°, 90°, 95° or 100°. Within this bending angle range, the strength of the connecting piece can be guaranteed, while minimizing the space occupied by the connecting piece, further improving the energy density of the battery. Moreover, it facilitates stamping and forming by the equipment.

[0034] Understandably, to reduce the space occupied by the connecting piece and for proper assembly, the extensions of the second welding part 200 and the third welding part 300 are arranged parallel to each other with a gap 400 between them. The gap 400 provides more clearance, ensuring that there is space to arrange other components after the connecting piece connects the cell tabs. The ends of the extensions of both the second welding part 200 and the third welding part 300 are provided with chamfered portions 500, which face the gap 400. The chamfered portions 500 serve two purposes: firstly, they act as a foolproof design, preventing incorrect assembly of the connecting piece; secondly, they further reduce the weight of the connecting piece, thereby increasing the energy density of the battery.

[0035] It should be noted that the connecting piece is formed by one-piece stamping.

[0036] like Figure 4 As shown, another aspect of this application provides a cover plate including a rivet 600, which is connected to the connecting piece mentioned above. The rivet 600 is also known as a pole post. The cover plate has a groove 610 at the location of the rivet 600 that matches the protrusion 130. The groove 610 and the protrusion 130 cooperate to perform the functions of positioning and reducing the longitudinal space occupation.

[0037] Another aspect of this application is a lithium battery, including the aforementioned connecting piece or cover plate.

[0038] In the description of this utility model, it should be noted that the terms "front," "rear," "left," "right," "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and 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" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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.

[0040] The scope of protection of this utility model is defined only by the claims. Thanks to the teachings of this utility model, those skilled in the art will readily recognize that alternative structures to the disclosed structure can be used as feasible alternative implementations, and that the disclosed implementations can be combined to produce new implementations, which also fall within the scope of the appended claims.

Claims

1. A bent lithium battery connector, comprising a first welding portion (100), a second welding portion (200), and a third welding portion (300), wherein the first welding portion (100) is used for welding the terminal post, and the second welding portion (200) and the third welding portion (300) are used for welding the battery cell tab; characterized in that, The second welding part (200) and the third welding part (300) are respectively connected to the first welding part (100) through a bending part (110). The first welding part (100) is located on different planes from the second welding part (200) and the third welding part (300) through the bending part (110). The bending part (110) is provided with a clearance (120), which makes gaps form between the first welding part (100) and the second welding part (200) and the third welding part (300).

2. The bent lithium battery connector according to claim 1, characterized in that, The second weld portion (200) and the third weld portion (300) extend away from the center of the first weld portion (100), and the clearance portion (120) extends towards the center of the first weld portion (100).

3. The bent lithium battery connector according to claim 1, characterized in that, The first welding part (100) includes a first welding surface (101) and a second welding surface (102) disposed opposite to each other, the second welding surface (102) being disposed in the direction of the battery cell; the first welding surface (101) is provided with a protrusion (130), and the second welding surface (102) is provided with a groove (131) corresponding to the position of the protrusion (130).

4. A bent lithium battery connector according to claim 3, characterized in that, The protruding direction of the convex bulge of the bent portion (110) is close to the second welding surface (102), and the second welding portion (200) and the third welding portion (300) are bent by the bent portion (110) and located on the side close to the first welding surface (101).

5. A bent lithium battery connector according to claim 4, characterized in that, The distance between the second welding part (200) and the third welding part (300) and the second welding surface (102) is 0.5mm to 1mm.

6. A bent lithium battery connector according to claim 1, characterized in that, The angle of the inner angle of the bending angle of the bending part (110) is 90°±10°.

7. A bent lithium battery connector according to claim 2, characterized in that, The extensions of the second welding part (200) and the third welding part (300) are arranged in parallel and are separated by a gap (400).

8. A bent lithium battery connector according to claim 7, characterized in that, Both the second welding part (200) and the extension of the third welding part (300) are provided with chamfered portions (500) at their ends, and the chamfered portions (500) are provided toward the interval (400).

9. A cover plate comprising rivets (600), characterized in that, The rivet (600) is connected to the connecting piece according to any one of claims 1-8; the cover plate has a groove (610) at the location of the rivet (600) that matches the protrusion (130).

10. A lithium battery, characterized in that, Includes the connecting piece as described in any one of claims 1-8 or the cover plate as described in claim 9.

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