Collecting plate of battery and lithium battery

Abstract

The utility model discloses a current collecting plate of a battery, the battery comprises a tab and a pole, the current collecting plate comprises a plate surface which is positioned at one axial end of the battery and comprises a tab welding area welded with the tab; the protruding part protrudes outwards relative to the disc face in the axial direction, the protruding part comprises an end wall and a side wall, the end wall is one end of the protruding part in the axial direction, the side wall is located between the disc face and the end wall in the axial direction, and the side wall comprises a pole welding area welded to the pole. According to the current collecting plate, the pole and the current collecting plate can be welded on the side wall of the protruding part, the pole and the current collecting plate are firmly welded together, the risk of melting through the current collecting plate is avoided, the manufacturing is simple, the structure is stable, and the overcurrent capability of the battery can be further ensured. The utility model also discloses a lithium battery.

Description

Technical Field

[0001] The utility model relates to the field of novel batteries, in particular to a current collecting plate of a battery and a lithium battery. Background Art

[0002] With the continuous development of technology, the demand for mobile devices, electric vehicles and other fields is increasing, placing higher demands on the energy density and current capacity of lithium batteries. Especially in the field of new energy electric vehicles, as the penetration rate of new energy electric vehicles increases, electric vehicles using cylindrical battery cells are gradually attracting users' attention.

[0003] The terminals in lithium batteries are a crucial component, connecting the positive and negative electrodes to the external circuit. Terminals are often welded to other components within the battery, making welding a critical step in lithium battery manufacturing because it directly impacts the battery's internal resistance, cycling performance, and safety. Poor welding can increase the battery's internal resistance, heat generation, and even cause a short circuit, impacting its performance and lifespan. The battery's complex internal structure further complicates the welding process, and carelessness can lead to meltthrough, severely impacting production efficiency.

[0004] Especially in cylindrical cells, the design schemes of cylindrical cells are different. Taking the positive output end of the cylindrical cell as an example, the pole and the collector are fixedly connected by welding. The main welding methods include lap welding, penetration welding, wire welding, etc. The specific connection method needs to be determined according to the structural scheme of the cell. Figure 1 As shown in the figure, the structural parts of the positive output end of the cylindrical battery cell mainly include aluminum pole 01, rivet ring 02, outer plastic 03, sealing ring, inner plastic 04, current collecting plate 05, steel shell assembly 06 and other components. In order to improve the energy density and overcurrent capacity of the battery cell, Figure 1 In the penetration welding area S01, the collector plate and the pole are connected by penetration welding to improve the stability of the connection. However, when welding a thin collector plate, melting through is likely to occur, causing a short circuit in the battery cell. Utility Model Content

[0005] In order to solve the above technical problems, the embodiment of the present utility model discloses a current collecting plate of a battery, wherein the battery includes a tab and a pole. The current collecting plate includes:

[0006] The disc is located at one end of the battery axial direction and includes a tab welding area welded to the tab;

[0007] The protrusion protrudes outward relative to the disk surface in the axial direction, and the protrusion includes

[0008] The end wall is one end of the protrusion along the axial direction.

[0009] The side wall is located between the disk surface and the end wall in the axial direction and includes a pole welding area welded to the pole.

[0010] By adopting the above technical solution, the pole and the collecting plate can be welded on the side wall of the protrusion, and the position of the pole welding can be adjusted. The pole can be firmly welded to the collecting plate without penetration welding. The manufacturing is simple, the structure is stable, and the production and processing yield is improved.

[0011] Optionally, the protrusion is a frustum structure, and the cross-sectional area of ​​the frustum structure increases along the direction from the end wall to the disk surface.

[0012] Optionally, the thicknesses of the end wall, the side wall and the disk surface are H1, H2 and H3 respectively, wherein H1=H2=H3, and / or the distance between the end wall and the disk surface is D, wherein 1mm<D<5mm, 1<D / H2<25.

[0013] Optionally, the thicknesses of the end wall, the side wall and the disk surface are H1, H2 and H3 respectively, wherein H1>H2>H3, and 0.2mm≤H3≤0.8mm.

[0014] Optionally, the protrusion includes an abutment boss, which extends outward from the side wall along the circumference of the protrusion, and the pole and the abutment boss abut against each other along the axial direction.

[0015] Optionally, the abutment boss is integrally formed with the side wall.

[0016] Optionally, the plurality of batteries are connected via tabs, and the end wall includes a tab welding area welded to the tabs.

[0017] Optionally, the disk surface and the protrusion are integrally formed.

[0018] Optionally, the disk surface includes a buffer zone, and the buffer zone protrudes toward the interior of the battery.

[0019] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a lithium battery, including the above-mentioned current collecting plate.

[0020] By adopting the above technical solution, the structural stability of the lithium battery can be improved, the battery energy density and the stability of the overcurrent capacity can also be improved, and the manufacturing and assembly are convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram showing the connection structure between the collector plate and the pole in the prior art is shown;

[0022] Figure 2A schematic structural diagram of a current collecting plate according to an embodiment of the present invention is shown;

[0023] Figure 3 A schematic structural diagram of a current collecting plate according to another embodiment of the present invention is shown;

[0024] Figure 4 A schematic diagram showing the structure of a current collecting plate and a pole after welding according to another embodiment of the present invention;

[0025] Figure 5 A schematic diagram of the structure of a current collecting plate with abutting bosses in one embodiment of the present invention is shown;

[0026] Figure 6 A schematic diagram showing the structure of a current collecting plate with an abutting boss and a pole after welding in one embodiment of the present invention is shown;

[0027] Figure 7 A schematic diagram of the planar structure of a current collecting disc according to an embodiment of the present invention is shown.

[0028] 01. Aluminum pole, 02. Riveted ring, 03. Outer plastic, 04. Inner plastic, 05. Collector plate, 06. Steel shell assembly, S01. Through-hole welding area, S02. Bar welding area,

[0029] 1. Collector plate, 2. Pole

[0030] 10. Disk, 11. Buffer, 20. Protrusion, 21. End wall, 22. Side wall, 23. Abutment boss

[0031] S1. Tab welding area, S2. Pole welding area, S3. Plate welding area DETAILED DESCRIPTION

[0032] The following is an explanation of the implementation of the present invention by means of specific specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this utility model are limited to this implementation. On the contrary, the purpose of introducing the utility model in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide an in-depth understanding of the present invention, the following description will contain many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0033] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0034] In the description of this embodiment, it should be noted that, unless otherwise specified or limited, the terms "disposed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this embodiment based on specific circumstances.

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0036] The first aspect of the present invention discloses a current collecting plate of a battery, wherein the battery comprises a terminal lug and a terminal column. Figure 2-6 As shown, the current collecting disc 1 includes a disc surface 10 and a protrusion 20. The disc surface 10 is located at one end of the battery in the axial direction and includes a tab welding area S1 welded to the tab; the protrusion 20 protrudes outwardly relative to the disc surface in the axial direction and includes an end wall 21 and a side wall 22. The end wall 21 is one end of the protrusion 20 in the axial direction, and the side wall 22 is located axially between the disc surface 10 and the end wall 21 and includes a pole welding area S2 welded to the pole. Figure 2 As shown, the axial direction is, for example, Figure 2 Direction A in.

[0037] Specifically, a current collecting disk 1 is provided at one end of the battery, that is, the end position of the battery, and the disk surface 10 is located on the end side of the battery and extends on a plane parallel to the end of the battery. The disk surface 10 can be welded to the tab, and the specific welding area is the tab welding area S1. The protrusion 20 protrudes outward from the disk surface 10, that is, the protrusion 20 takes the disk surface 10 as the starting point and extends in a direction away from the battery. Since the battery structure needs to be closed, the protrusion 20 has an end wall 21, and a side wall 22 is formed to connect the disk surface 10 and the end wall 21 in the axial direction. Specifically, the end wall 21 and the disk surface 10 are two parallel surfaces.

[0038] Under this structural design, further reference Figure 4The welding position of the pole 2 can be shifted to the side wall 22, specifically to the S2 region. Instead of using penetration welding to weld the pole 2 to the current collecting plate 1, the pole 2 can be securely connected to the current collecting plate 1 using lap welding, without penetrating the plate. This improves manufacturing consistency, significantly increases production efficiency, and results in a high manufacturing yield and improved battery performance stability. Furthermore, the pole 2 can be arranged around the protrusion 20, specifically around the side wall 22, abutting against it, and then the two can be welded together using lap welding.

[0039] In a specific embodiment of the present invention, one end of the battery is the positive terminal, and the current collecting plate is the positive electrode current collecting plate of the battery, which can improve the connection stability of the positive electrode and prevent the positive electrode from melting through, thereby ensuring the energy density and current capacity of the battery.

[0040] In a specific embodiment of the present invention, the battery is a cylindrical battery. Accordingly, Figure 7 As shown, the disk surface 10 of the collecting disk 1 is circular, forming a disk-shaped structure.

[0041] In a specific embodiment of the present invention, Figure 2-6 As shown, the protrusion 20 is a truncated cone structure and extends in a direction from the end wall 21 to the disk surface 10 (as shown in FIG. Figure 4 In the direction B shown in the figure, the cross-sectional area of ​​the truncated cone structure becomes larger. Especially in the case of a cylindrical battery, the shape of the current collecting disk 1 can be seen as a truncated cone protruding outward from the disk. Taking the disk surface 10 as the starting point, the side wall 22 is not an upright structure, that is, the side wall 22 is not at a right angle to the disk surface 10. The side wall 22 has a certain inclination angle and is inclined toward the center position of the protrusion 20. The protrusion 20 is a hollow truncated cone with a certain taper. The side wall 22 is the side of the truncated cone structure, the end wall 21 is the top surface of the truncated cone structure, and the truncated cone structure does not have a bottom surface. Through this arrangement, after the pole 2 is welded to the side wall 22 by lap welding, the inclination of the side wall 22 can also provide certain mechanical support for the pole 2, especially in the direction along the axial direction of the battery, which can give the pole 2 a certain supporting force, making the connection between the pole 2 and the current collecting disk 1 more stable, thereby ensuring the reliability of the battery end structure.

[0042] In the embodiment of the present invention, the disk surface 10, the end wall 21 and the side wall 22 all have a certain wall thickness, such as Figure 2 and Figure 3 As shown, the wall thickness of the disk surface 10 is H1, the wall thickness of the end wall 21 is H3, and the wall thickness of the side wall 22 is H2.

[0043] In a specific embodiment of the present invention, Figure 2As shown, the collector plate 1 has a uniform wall thickness structure, H1 = H2 = H3. That is, the plate surface 10, end wall 21, and side wall 22 are of uniform thickness, with the thickness of each part being consistent. More specifically, the plate surface 10 and protrusion 20 are integrally formed. In other words, the entire collector plate 1 is integrally stamped and stretched, which conveniently achieves a thickness relationship of H1 = H2 = H3 for each part.

[0044] More specifically, if Figure 2 As shown, the distance between the end wall 21 and the disk surface 10 is D. That is, the length from the bottom of the end wall 21 to the top of the disk surface 10 is D. Here, 1mm < D < 5mm, and 1 < D / H2 < 25. With this arrangement, the protrusion 20 can have more stable mechanical properties, a more reliable structure, and further enhance the weld to the terminal.

[0045] In a specific embodiment of the present invention, Figure 3 As shown, the collector plate 1 has a structure with a gradual wall thickness, H1>H2>H3. That is, the plate surface 10, end wall 21, and side wall 22 are not structures of equal wall thickness. The plate surface 10 is the thinnest, the end wall 21 is the thickest, and the side wall 22 is in the middle. From the plate surface 10 to the side wall 22 and then to the end wall 21, the wall thickness gradually changes from thin to thick, making the structure of the protrusion 20 more stable. Furthermore, considering that the welding position between the pole and the collector plate is near the end wall 21 in the side wall 22, the end wall 21 is the thickest. Therefore, the end wall 21 is relatively thin. This ensures that the connection between the end wall 21 and the side wall 22 is both convenient and stable for welding and strong. Furthermore, the plate surface 10 and the protrusion 20 are integrally formed. When the protrusion 20 is integrally formed with the disc surface 10, the sidewall 22 connecting the end wall 21 and the disc surface 10 has a moderate thickness. This not only improves the structural stability of the collector disc 1, but also facilitates its manufacture and stretching. Furthermore, during stretching, the connection between the sidewall 22 and the disc surface 10, and between the sidewall 22 and the end wall 21, naturally forms a stable bending zone. The gradual wall thickness ensures reliable mechanical stability at these connections. Specifically, 0.2mm ≤ H3 ≤ 0.8mm.

[0046] In a specific embodiment of the present invention, Figure 5-6The protrusion 20 also includes an abutment boss 23. Along the circumference of the protrusion 20, the abutment boss 23 extends outward from the side wall 22, and along the axial direction of the battery, the pole 2 and the abutment boss 23 abut each other. The abutment boss 23 can be set in a position slightly above the middle of the side wall 22, closer to the welding position between the pole 2 and the side wall 22. The abutment boss 23 can further provide support for the pole 2, improve the overall mechanical properties of the protrusion 20, and facilitate the positioning of the current collecting plate 1 and the pole 2 during welding. In addition, during the use of the battery, some gas may be generated from the battery, thereby generating a certain thrust on the protrusion 20. By utilizing this thrust, the abutment boss 23 can improve the tightness of the connection between the current collecting plate 1 and the pole 2, enhance the sealing of the weld, and further improve the battery performance.

[0047] Specifically, the abutment boss 23 is a structure fixedly connected to the side wall 22. Preferably, the abutment boss 23 and the side wall 22 are integrally formed. Specifically, during the manufacturing process, the side wall 22 can be bent inward in the upper middle area of ​​the protrusion 20, thereby forming a step-shaped abutment boss 23. It can be considered that with the abutment boss 23 as the boundary, the protrusions 20 on both sides thereof will undergo a sudden change in cross-sectional area, and the side wall 22 forms a dislocation. Along the direction from the connection part of the side wall 22 and the disk surface 10 to the end wall 21, the side wall 22 forms an inwardly contracted part at the abutment boss 23. Furthermore, the pole 2 can be designed to have a structure corresponding to the shape of the abutment boss 23, forming a matching relationship, which makes assembly more convenient and the abutment can also be more stable.

[0048] In a specific embodiment of the present invention, multiple batteries are connected by tabs, and the end wall 21 includes a tab welding area S3 for welding with the tabs. Since the current collecting plate 1 can be directly welded with the tabs without the need for other structures for connection, the battery's current capacity is improved. Figure 1 As shown, in the bar welding area S02, the aluminum pole 01 is welded to the bar, so that it can be grouped in the PACK. At this time, the output capacity of the battery at this end is related to the welding area between the current collecting plate 05 and the welding pin, the welding area between the welding pin and the aluminum pole 01, and the welding area between the bar and the aluminum pole 01, and is subject to multiple restrictions. However, through the current collecting plate structure of the present invention, the current collecting plate 1 can be directly welded to the bar in the bar welding area S3, as shown in FIG. Figure 7 As shown, the area of ​​S3 region is large, and is much larger than the sum of the welding area between the collecting plate 05 and the welding pin, the welding area between the welding pin and the aluminum pole 01, and the welding area between the bar and the aluminum pole 01. This increases the cross-sectional area for current flow, and eliminates the need for current to be conducted entirely through the pole, thereby reducing the number of current transfers, increasing transmission efficiency, and improving battery performance.

[0049] In a specific embodiment of the present invention, Figure 2 As shown, the disc 10 includes a buffer zone 11 that protrudes toward the interior of the battery. Specifically, during manufacturing, the disc 10 can be bent to form a convex, bent rib area, which serves as the buffer zone 11. The structural design of the buffer zone 11 can reduce vibration amplitude, absorb and disperse vibration energy, and weaken the vibration energy transmitted from the cell casing to the winding core during battery cell vibration. This reduces vibration interference with the internal structure of the cell, helps maintain the cell's optimal operating state, and improves its performance stability.

[0050] The second aspect of the present invention discloses a lithium battery that utilizes the aforementioned current collecting plate structure, achieving enhanced and stable current handling capacity, improving the battery's safety and cycle performance, and simplifying manufacturing and processing. The lithium battery of the present invention can also be used in a pack, electrically connected to other batteries via tabs to form a battery pack.

[0051] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above description is provided to further illustrate the present invention in conjunction with specific embodiments, and that the present invention should not be construed as being limited to these descriptions. Those skilled in the art may make various changes in form and detail, including simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A current collecting plate of a battery, the battery comprising a terminal lug and a terminal post, characterized in that: The collecting plate comprises: A disk surface is located at one end of the battery in the axial direction and includes a tab welding area welded to the tab; A protrusion protrudes outward relative to the disk surface along the axial direction, the protrusion comprising The end wall is one end of the protrusion along the axial direction, The side wall is located between the disk surface and the end wall along the axial direction and includes a pole welding area welded to the pole.

2. A current collecting tray for a battery as claimed in claim 1, characterized in that: The protrusion is a truncated cone structure, and the cross-sectional area of ​​the truncated cone structure increases along the direction from the end wall to the disk surface.

3. A current collecting tray for a battery as claimed in claim 2, characterized in that: The thicknesses of the end wall, the side wall and the disk surface are H1, H2 and H3 respectively, wherein H1=H2=H3, and / or the distance between the end wall and the disk surface is D, wherein 1mm<D<5mm, 1<D / H2<25.

4. A current collecting tray for a battery as claimed in claim 2, characterized in that: The thicknesses of the end wall, the side wall and the disk surface are H1, H2 and H3 respectively, wherein H1>H2>H3, and 0.2mm≤H3≤0.8mm.

5. The current collecting tray of a battery according to claim 1, characterized in that: The protrusion includes an abutting boss, which extends outward from the side wall along the circumference of the protrusion. Along the axial direction, the pole and the abutting boss abut against each other.

6. A current collecting tray for a battery as claimed in claim 5, characterized in that: The abutting boss is integrally formed with the side wall.

7. A current collecting tray for a battery as claimed in claim 1, characterized in that: The plurality of batteries are connected by tabs, and the end wall includes a tab welding area welded to the tabs.

8. The current collecting tray of a battery according to claim 1, characterized in that: The disk surface and the protrusion are integrally formed.

9. The current collecting tray of a battery according to claim 1, wherein: The disk surface includes a buffer zone protruding toward the interior of the battery.

10. A lithium battery, characterized in that: The invention comprises the collecting plate according to any one of claims 1 to 9.

Images