A current collector plate and cylindrical battery

Abstract

The utility model discloses a kind of current collector plate and cylindrical battery, current collector plate includes the disc body and tail body connected with each other, the lower end surface of disc body has a plurality of welding area welded with the pole lug of battery cell, wire type welding mark is equipped in each welding area, welding area is the rectangle of just accommodating welding mark, the area of each welding area is 3.3~4.4% of the area of disc body lower end surface.The cylindrical battery includes current collector plate, roll core, has the cylindrical shell with opening, cover plate, roll core is located in cylindrical shell, cover plate is covered and is located in opening, current collector plate is located between cover plate and roll core, and is connected with roll core, cover plate, the center of current collector plate is equipped with first through-hole, current collector plate is also equipped with a plurality of second through-hole.The current collector plate and cylindrical battery of the utility model can ensure that the connection structure strength of current collector plate and the pole lug of battery cell meets production requirement, can avoid that current collector plate and battery cell are overheated due to too small overcurrent area, and further reduce the difficulty of manufacturing welding mark on current collector plate, reduce cost.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a current collector and a cylindrical battery. Background Technology

[0002] Currently, the primary method of connecting the current collector and the winding core is welding. Technicians create solder marks on the surface of the current collector to weld the winding core's tabs to the current collector within the marked area, thus establishing a conductive connection. However, the applicant has discovered that if the welding area is too small, it directly reduces the effective current-carrying area between the winding core and the current collector, leading to increased resistance at the connection point of the cylindrical battery. This results in concentrated heat generation at the weld, posing a safety risk to the battery. Furthermore, the increased temperature within the welding area weakens the welded connection strength, making the current collector and winding core prone to disconnection. Of course, a small welding area itself also contributes to a weak connection strength between the current collector and the winding core, making them susceptible to breakage.

[0003] Furthermore, the welding area of ​​the current collector is not necessarily better the larger it is. If the welding area is too large, the time spent welding the tabs of the coiled core to the current collector during the actual production of cylindrical batteries will increase, leading to lower battery production efficiency and increased battery manufacturing costs. At the same time, because the weldable area on the current collector is too large, the actual welding position of the tabs may deviate from the intended position, and some of the tab body may extend beyond the current collector without being welded. This results in the actual welding area between the tab and the current collector being smaller than the intended weldable area, and the multiple actual welding areas are not evenly distributed on the current collector, affecting battery performance.

[0004] To address the aforementioned issues, existing technology discloses a utility model patent entitled "A Current Collector and a Battery." The current collector includes a body with welding areas for welding to the electrode assembly. These welding areas are multiple and spaced apart along the circumferential direction of the body. Each welding area has a set of solder marks, which includes multiple sequentially arranged solder points. The solder marks are V-shaped or arc-shaped. According to this utility model, the current collector body has V-shaped solder marks, increasing the length of the welding path, enlarging the welding area between the current collector and the electrode assembly, and improving connection stability, thereby ensuring the battery's current carrying capacity and reliability. However, in this utility model, to improve connection stability and enhance current carrying capacity, the area occupied by the solder marks on the current collector is almost two-thirds of the entire surface area of ​​the current collector. It clearly does not consider the negative impact of an excessively large welding area on battery performance and welding quality. Moreover, since the solder mark on the current collector is composed of several solder points, when the current collector is actually produced, the technicians need to control the solder mark manufacturing device to manufacture solder points one by one at multiple locations on the current collector. The requirements for the movement accuracy of the solder mark manufacturing device and the solder mark manufacturing accuracy are relatively high, which leads to an increase in the manufacturing cost of the current collector and the battery. Utility Model Content

[0005] To address the aforementioned technical deficiencies in the existing technology, this utility model provides a current collector and a cylindrical battery, which can ensure that the connection structure strength between the current collector and the battery cell's tabs meets production requirements, avoid overheating between the current collector and the battery cell due to insufficient current flow area, and further reduce the difficulty of manufacturing solder marks on the current collector, thereby reducing costs.

[0006] The technical solution of this utility model to solve the above problems is: to provide a current collector, the current collector including a disk body and a tail body connected to each other, the lower end surface of the disk body has a plurality of welding areas for welding to the tabs of the battery cell, each welding area is provided with a linear solder mark, the welding area is a rectangle that just accommodates the solder mark, and the area of ​​each welding area is 3.3 to 4.4% of the area of ​​the lower end surface of the disk body.

[0007] Furthermore, the sum of the areas of the plurality of welding areas is 13.3 to 17.7% of the area of ​​the lower end surface of the disc.

[0008] Furthermore, the minimum distance from the welding area to the circumferential edge of the disk is 0.8 to 1.4 mm.

[0009] Furthermore, the tail body is provided with a tail groove for reducing the width of the tail body, and the tail groove is symmetrically arranged at the connection position between the tail body and the disc body.

[0010] This utility model also provides a cylindrical battery, including a current collector as described above, a core, a cylindrical shell with an opening, and a cover plate. The core is disposed inside the cylindrical shell, and the cover plate covers the opening. The current collector is disposed between the cover plate and the core and is connected to the core and the cover plate. The current collector has a first through hole at its center and a plurality of second through holes on its surface.

[0011] Furthermore, the radius of the disc body is 86.4% to 92.3% of the radius of the winding core.

[0012] Furthermore, the radius of the first through hole is 21.6 to 27.5% of the radius of the winding core.

[0013] Furthermore, the radius of the second through hole is 11.8 to 17.7% of the radius of the winding core.

[0014] Furthermore, the core has a central hole, the radius of which is 15.7 to 18.7% of the radius of the core.

[0015] Furthermore, the radius of the core is 9.18–11.18 mm.

[0016] Furthermore, multiple welding areas are equidistantly arranged along the circumferential direction of the disc, and multiple second through holes are equidistantly arranged along the circumferential direction; in a clockwise or counterclockwise direction, except for the first and last welding areas, a second through hole is provided between any two adjacent welding areas.

[0017] Furthermore, the minimum distance from the welding area to the edge of the first through hole is 0.7 to 1.3 mm.

[0018] Furthermore, the minimum distance between the welding area and the edge of the second through hole is 0.4 to 0.8 mm.

[0019] The beneficial effects of this utility model are:

[0020] For the current collector of this utility model, by setting linear solder marks on the current collector and reasonably controlling the area of ​​the rectangular region occupied by the linear solder marks, the connection structure strength between the current collector and the battery cell tabs is guaranteed, and the overheating between the current collector and the battery cell due to the small overcurrent area is effectively avoided.

[0021] In addition, the rectangular area occupied by the linear solder mark does not occupy too much of the lower end face area of ​​the manifold, thus reducing the difficulty of manufacturing this manifold separately.

[0022] Moreover, when welding the tabs and current collectors of the battery cell of this utility model, the tab technicians do not need to worry about the current collector and the tab not making full contact due to the welding area being too large, thus avoiding welding quality defects and unstable welding quality.

[0023] For the cylindrical battery of this utility model, the multiple welding areas on the current collector are arranged equidistantly along the circumferential direction and staggered from the second through holes that are equidistantly arranged along the circumferential direction. The arrangement of the multiple welding areas with the outer edge of the plate and the edge of the first through hole is reasonable. This arrangement further improves the welding quality of the electrode tabs of the welded core and the current collector, so that the electrode tabs of the welded core and the current collector can be connected more stably, improving the electrical performance of the cylindrical battery. It also ensures that the arrangement of the welding areas will not affect the subsequent operation of injecting electrolyte and venting air into the cylindrical battery. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In these drawings, similar reference numerals are used to denote similar elements. The drawings described below are some embodiments of the present invention, but not all embodiments. Other drawings will be readily available to those skilled in the art based on these drawings without any inventive effort.

[0025] Figure 1 This is a top view of the collector disk in a specific embodiment of the present utility model, wherein the collector disk is fully deployed;

[0026] Figure 2 This is a top view of a portion of the fan-shaped area of ​​the current collector in a specific embodiment of the present utility model. The specific shape and size of the welding area are marked accordingly, and the top view of the end face of the cylindrical battery core is drawn below the current collector for size comparison.

[0027] Figure 3 This is an exploded view of a cylindrical battery according to a specific embodiment of the present invention; wherein the tail body is bent upward above the disc body for connection with the cover plate.

[0028] Relevant annotations in the image:

[0029] 1-Collector plate, 11-Plate body, 12-Tail body, 13-Welding area, 14-Linear weld mark, 15-First through hole, 16-Second through hole, 17-Tail groove;

[0030] 2-Core, 21-Core center hole, 3-Cylindrical shell, 31-Opening, 4-Cover plate;

[0031] R0 - Radius of the core;

[0032] R1 - Radius of the disk;

[0033] R2 - Radius of the first through hole;

[0034] R3 - Radius of the second through hole;

[0035] W1 - Minimum distance from the welding area to the outer circumference of the disk;

[0036] W2 - Minimum distance from the welding area to the second through hole;

[0037] W3 - Minimum distance from the welding area to the first through hole;

[0038] W4 - Width of the welding area;

[0039] W5 - Length of the welding area. Detailed Implementation

[0040] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0041] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They 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 of this utility model. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of those features. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0042] 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.

[0043] Now according to Figures 1-3 The current collector and cylindrical battery of this utility model will be described.

[0044] It should be noted that, in order to facilitate those skilled in the art to understand the technical solution of this embodiment, Figure 1 The collector disk shown Figure 2 The portion of the manifold shown is inverted and facing upwards to allow for visualization of the linear solder marks; in fact... Figure 1 and Figure 2 The end face of the manifold in the middle has a linear solder mark. Figure 3 The winding core is positioned towards the center.

[0045] Please see Figure 1 A specific embodiment of the present utility model is a collector plate, the collector plate 1 includes a plate body 11 and a tail body 12 connected to each other.

[0046] Specifically, with Figure 1 Taking the orientation shown as an example, the tail body 12 and the disk body 11 are integrally formed. The disk body 11 is generally circular, but there is a notch at the lower end of the disk body 11. The tail body 12 is integrally connected to the disk body 11 at the notch. In this way, since the tail body 12 cannot be bent exactly at the connection root position of the tail body 12 every time, when the technician bends the tail body 12 upward to connect with the cover plate 4 of the cylindrical battery, the remaining part at the connection root position of the tail body 12 can be just accommodated by the notch, so as to ensure that the size of the current collector 1 does not exceed the area of ​​the opening of the cylindrical battery casing, and ensure that the current collector 1 can be installed inside the cylindrical battery.

[0047] It should be noted that in some embodiments of this utility model, the disk body 11 of the current collector 1 can also be other shapes, such as regular shapes like rectangles or squares, and the corresponding applied battery can also be a square battery or other types of batteries.

[0048] Further, please refer to Figure 1 In some embodiments of this utility model, the tail body 12 is provided with a tail groove 17 to reduce the width of the tail body 12. The tail groove 17 is symmetrically arranged at the connection position between the tail body 12 and the disc body 11. In this way, the overcurrent capacity of the tail body 12 will be limited at the position of the tail groove 17, so that when a high-intensity current exceeding the overcurrent limit of the tail body 12 flows through the tail body 12 to the battery cell, the tail body 12 will melt in time, thereby protecting the battery.

[0049] For further details, please refer to Figure 1In some embodiments of this utility model, the surface of the disk body 11 is provided with four welding areas 13 and three first through holes 15. Each of the four welding areas 13 is just enough to accommodate a linear solder mark 14. The linear solder mark 14 is a continuous wavy line. The welding area 13 is a rectangular area that can just accommodate the linear solder mark 14. The current collector 1 is connected to the electrode tab of the battery cell by welding through these four linear solder marks 14.

[0050] Furthermore, the four welding areas 13 are equidistantly arranged along the circumference of the disc body 11, and the three second through holes 16 are equidistantly arranged along the circumference; in the clockwise or counterclockwise direction, except for the first and last welding areas 13, a second through hole 16 is provided between any two adjacent welding areas 13.

[0051] In this embodiment, a tail body 12 is provided between the two welding areas 13 at the head and tail, as well as a notch to improve the overall size tolerance of the collector plate 1. Due to the presence of the notch, the linear solder mark 14 is not suitable for placement here.

[0052] It should be noted that although the welding area 13 is rectangular in this embodiment, the specific shape and size of the welding area 13 actually vary with the corresponding shape of the linear solder mark 14. For example, if the linear solder mark 14 is set as a circular vortex, then the welding area 13 that can just accommodate the linear solder mark 14 may be a square.

[0053] Furthermore, in some embodiments of this utility model, the area of ​​the welding area 13 is S10, S10 = W4 * W5, and the overall area of ​​the disk 11 is S0. For ease of calculation, S0 is considered as the area of ​​a circle with radius R0.

[0054] In this regard, taking four linear solder marks as an example, in order to ensure the welding stability of the linear solder marks 14 and the electrode tabs of the battery cell, the area S10 of each welding area 13 is 3.3 to 4.4% of the area S0 of the lower end face of the disk body 11.

[0055] In addition, the area percentage of the four welding areas 13 (4*S10) / S0 = 13.3 to 17.7.

[0056] It should be noted that in this embodiment, the sum of the area percentages of the four welding regions 13 is actually (3.3 to 4.4%) * 4 = 13.2 to 17.6%. This is smaller than the value in the previous paragraph because this application allows an upper limit error of 0.1% for the sum of the area percentages of the four welding regions 13 in order to appropriately improve the welding error tolerance.

[0057] Furthermore, in some embodiments of this utility model, in order to avoid the situation where the welding area 13 is too close to the outer edge of the disk body 11, causing some of the electrode tabs of the battery cell to protrude outside the disk body 11 when they are welded to the corresponding welding area 13, thus affecting the installation quality of the current collector 1, the minimum distance from the welding area 13 to the circumferential edge of the disk body 11 is 0.8 to 1.4 mm.

[0058] Similarly, the collector plate 1 is provided with a first through hole 15 and a second through hole 16. In order to avoid the electrode tabs being exposed at the first through hole 15 and the second through hole 16, the minimum distance from the welding area 13 to the first through hole 15 is 0.7 to 1.3 mm. The minimum distance between the welding area 13 and the edge of the second through hole 16 is 0.4 to 0.8 mm.

[0059] This utility model also discloses a cylindrical battery, including the current collector 1 in any of the above embodiments, as well as the winding core 2, the cylindrical shell 3 with an opening 31, and the cover plate 4.

[0060] Specifically, please refer to Figure 3 The core 2 is inserted into the cylindrical shell 3, and the opening 31 is located at the upper end of the cylindrical shell 3. The cover plate 4 is placed at the opening 31. The collector plate 1 is located between the cover plate 4 and the core 2. The plate body 11 of the collector plate 1 is connected to the electrode lug of the core 2 by four linear weld marks 14. The tail body 12 of the collector plate 1 can be connected to the cover plate 4 after being bent upward. The center of the collector plate 1 is provided with a first through hole 15, and the collector plate 1 is also provided with three second through holes 16.

[0061] The four welding areas 13 are equidistantly arranged along the circumference of the disc body 11, and the three second through holes 16 are equidistantly arranged along the circumference. In the clockwise or counterclockwise direction, except for the first and last welding areas 13, a second through hole 16 is provided between any two adjacent welding areas 13.

[0062] Furthermore, when the core 2 is installed into the battery, the opening of the casing is usually sealed by mechanical sealing with a grooving. Due to the grooving and mechanical sealing, the shell wall of the cylindrical shell 3 at the grooving position will deform towards the center of the cylindrical shell 3. In order to prevent the current collector 11 from being too large and close to the diameter of the core 2, which would cause poor positive electrode coating after the current collector 1 and the core 2 are welded together, the shell wall at the grooving position will contact the edge of the positive electrode current collector 1.

[0063] In some embodiments of this utility model, the radius R1 of the disc body 11 is 86.4 to 92.3% of the radius R0 of the core 2, in order to reduce the risk of battery short circuit.

[0064] In addition, the radius of the current collector 1 is not too small, which also avoids the problem that the area of ​​the weldable area 13 between the disk body 11 and the core 2 becomes smaller due to the size of the current collector 1 being too small, thus preventing the current carrying capacity of the disk body 11 from weakening and affecting the performance of the battery.

[0065] Furthermore, in some embodiments of this utility model, in order to reasonably arrange the first through hole 15 and the second through hole 16 so as to ensure the normal exhaust function and exhaust speed of the first through hole 15 and the second through hole 16, and the normal liquid injection function and liquid injection speed of the first through hole 15, while not making the first through hole 15 too large and affecting the flow capacity of the collector plate 1, the radius R2 of the first through hole 15 is 21.6 to 27.5% of the radius R0 of the core 2, and the radius R3 of the second through hole 16 is 11.8 to 17.7% of the radius R0 of the core 2.

[0066] In addition, in order to ensure that the electrolyte can quickly penetrate into the interior of the core 2 along the center hole 21 of the core 2, thus ensuring the electrolyte injection efficiency of the battery, shortening the battery manufacturing time, reducing the battery manufacturing cost, and preventing the core 2 from becoming too large due to the radius of the center hole 21, which would lead to increased difficulty in inserting the core 2 into the casing, reduced yield, increased battery manufacturing cost, and decreased battery energy density, the radius of the center hole 21 is 15.7 to 18.7% of the radius of the core 2.

[0067] Furthermore, in some embodiments of this utility model, in order to further improve the adaptability of the current collector 1 and ensure the best performance of the current collector 1, in the cylindrical battery with the current collector 1 in this embodiment, the radius of the core 2 of the cylindrical battery is 9.18 to 11.18 mm.

[0068] Anything not mentioned above applies to existing technologies.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A current collector plate, characterized by, The current collector (1) includes a disk body (11) and a tail body (12) connected to each other. The lower end face of the disk body (11) has multiple welding areas (13) for welding to the tabs of the battery cells. Each welding area (13) is provided with a linear solder mark (14). The welding area (13) is a rectangle that can just accommodate the solder mark. The area of ​​each welding area (13) is 3.3 to 4.4% of the area of ​​the lower end face of the disk body (11).

2. The collector disk as described in claim 1, characterized in that, The sum of the areas of the plurality of welding areas (13) is 13.3 to 17.7% of the area of ​​the lower end face of the disc (11).

3. The collector disk as described in claim 1, characterized in that, The minimum distance from the welding area (13) to the circumferential edge of the disk body (11) is 0.8 to 1.4 mm.

4. A cylindrical battery, characterized in that, The device includes a collector plate (1) as described in any one of claims 1-3, a core (2), a cylindrical shell (3) with an opening (31), and a cover plate (4). The core (2) is disposed inside the cylindrical shell (3), and the cover plate (4) covers the opening (31). The collector plate (1) is disposed between the cover plate (4) and the core (2) and is connected to the core (2) and the cover plate (4). The collector plate (1) has a first through hole (15) at its center and a plurality of second through holes (16) on the collector plate (1).

5. The cylindrical battery as described in claim 4, characterized in that, The radius of the disc body (11) is 86.4 to 92.3% of the radius of the core (2).

6. The cylindrical battery as described in claim 4, characterized in that, The radius of the first through hole (15) is 21.6 to 27.5% of the radius of the core (2).

7. The cylindrical battery as described in claim 4, characterized in that, The radius of the second through hole (16) is 11.8 to 17.7% of the radius of the core (2).

8. The cylindrical battery as described in claim 4, characterized in that, The core (2) has a core center hole (21), the radius of which is 15.7 to 18.7% of the radius of the core (2).

9. The cylindrical battery as described in claim 4, characterized in that, The radius of the core (2) is 9.18 to 11.18 mm.

10. The cylindrical battery as described in claim 4, characterized in that, The minimum distance from the welding area (13) to the edge of the first through hole (15) is 0.7 to 1.3 mm, and the minimum distance from the welding area (13) to the edge of the second through hole (16) is 0.4 to 0.8 mm.

Images