Cylindrical battery

Abstract

The utility model relates to the technical field of batteries, and provides a cylindrical battery which comprises a battery cell, the battery cell comprises a battery cell main body and a first tab, the first tab extends out of the battery cell main body, and the first tab comprises a plurality of single tabs along the radial direction of the battery cell; the first current collecting piece is connected with the first tab in a welding manner, and a first welding wire is formed on the first current collecting piece; wherein each single tab is provided with a first end connected with the battery cell main body, and the extension direction of the first end is not parallel to the extension direction of the first welding wire, so that welding energy which penetrates through the adjacent single tab and is hit on the battery cell main body in the welding process of the first current collecting piece and the first tab can be reduced, and the problem that the battery cell main body is damaged is avoided; therefore, the safe use performance of the cylindrical battery is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a cylindrical battery. Background Art

[0002] In the related art, the tabs of a cylindrical battery can be electrically connected through a current collecting plate and a pole assembly, and the tabs and the current collecting plate can be connected by welding. When the tabs and the current collecting plate are welded, the battery cell body may be damaged due to the influence of welding energy. Utility Model Content

[0003] The utility model provides a cylindrical battery to improve the use performance of the cylindrical battery.

[0004] The utility model provides a cylindrical battery, comprising:

[0005] A battery cell, the battery cell comprising a battery cell body and a first pole ear, the first pole ear extending from the battery cell body, and along the radial direction of the battery cell, the first pole ear comprises a plurality of single-piece pole ears;

[0006] A first current collecting member, the first current collecting member is welded to the first electrode tab, and a first welding line is formed on the first current collecting member;

[0007] The single-piece electrode tab has a first end connected to the battery body, and an extension direction of the first end is not parallel to an extension direction of the first welding wire.

[0008] The cylindrical battery of the utility model embodiment includes a battery cell and a first current collector, the battery cell and the first current collector are electrically connected, the battery cell includes a battery cell body and a first pole ear extending from the battery cell body, the first pole ear is formed by gathering a plurality of single-piece pole ears, thereby ensuring the overall current flow capacity of the first pole ear, and the first current collector is welded to the first pole ear, thereby ensuring the connection stability between the first current collector and the first pole ear, and further ensuring the current flow capacity between the first current collector and the first pole ear, and the extension direction of the first welding line on the first current collector is not parallel to the extension direction of the first end of the single-piece pole ear connected to the battery cell body, thereby reducing the welding energy during the welding process of the first current collector and the first pole ear from passing through the adjacent single-piece pole ears to hit the battery cell body, avoiding the problem of damaging the battery cell body, thereby effectively improving the safe use performance of the cylindrical battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to better understand the present disclosure, reference may be made to the embodiments shown in the following drawings. The components in the drawings are not necessarily to scale, and related elements may be omitted in order to emphasize and clearly illustrate the technical features of the present disclosure. In addition, related elements or components may have different arrangements as known in the art. In addition, in the drawings, the same reference numerals represent the same or similar components in each drawing. Among them:

[0010] Figure 1 is a schematic structural diagram of a cylindrical battery according to an exemplary embodiment;

[0011] Figure 2 is a partial structural schematic diagram of a cylindrical battery according to an exemplary embodiment;

[0012] Figure 3 is a schematic structural diagram of a cylindrical battery cell according to an exemplary embodiment;

[0013] Figure 4 is a schematic diagram of a cross-sectional structure of a cylindrical battery cell according to an exemplary embodiment;

[0014] Figure 5 is a schematic structural diagram of a single-piece tab of a cylindrical battery according to an exemplary embodiment;

[0015] Figure 6 FIG. 1 is a schematic structural diagram of a first current collector of a cylindrical battery according to an exemplary embodiment.

[0016] The following are the descriptions of the reference numerals:

[0017] 10. Battery cell; 11. Battery cell body; 12. First pole ear; 121. Monolithic pole ear; 1211. First end; 1212. Second end; 122. Gap area; 13. Second pole ear; 20. First current collector; 21. First welding wire; 22. First area; 221. First arc end; 222. Second arc end; 23. Pole connection area; 30. Second current collector; 31. Second welding wire; 32. Second area; 321. Third arc end; 322. Fourth arc end; 33. Shell connection area; 40. Battery shell; 50. Pole assembly. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings in the exemplary embodiments of the present disclosure to clearly and completely describe the technical solutions in the exemplary embodiments of the present disclosure. The exemplary embodiments described herein are only for illustrative purposes and are not intended to limit the scope of protection of the present disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of the present disclosure.

[0019] In the description of the present disclosure, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; the term "plurality" refers to two or more; the term "and / or" includes any and all combinations of one or more associated listed items. In particular, reference to "the / the" object or "an" object is also intended to indicate one of a possible plurality of such objects.

[0020] Unless otherwise specified or explained, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.

[0021] Further, in the description of the present disclosure, it should be understood that the directional words such as "upper", "lower", "inner", "outer" and the like described in the exemplary embodiments of the present disclosure are described at the angles shown in the accompanying drawings and should not be understood as limitations on the exemplary embodiments of the present disclosure. It should also be understood that, in the context, when it is mentioned that an element or feature is connected to another element (one or more) "upper", "lower", or "inner", "outer", it can not only be directly connected to the other (one or more) elements "upper", "lower", "inner", "outer", but also can be indirectly connected to the other (one or more) elements "upper", "lower", "inner", "outer" through an intermediate element.

[0022] An embodiment of the present invention provides a cylindrical battery. Figures 1 to 6 The cylindrical battery includes: a battery cell 10, the battery cell 10 includes a battery cell body 11 and a first pole ear 12, the first pole ear 12 extends from the battery cell body 11, and along the radial direction of the battery cell 10, the first pole ear 12 includes a plurality of single-piece pole ears 121; a first current collector 20, the first current collector 20 is welded to the first pole ear 12, and a first welding wire 21 is formed on the first current collector 20; wherein the single-piece pole ear 121 has a first end 1211 connected to the battery cell body 11, and an extension direction of the first end 1211 is not parallel to an extension direction of the first welding wire 21.

[0023] A cylindrical battery in one embodiment of the utility model includes a battery cell 10 and a first current collector 20, the battery cell 10 and the first current collector 20 are electrically connected, the battery cell 10 includes a battery cell body 11 and a first pole ear 12 extending from the battery cell body 11, the first pole ear 12 is formed by gathering a plurality of single-piece pole ears 121, thereby ensuring the overall current capacity of the first pole ear 12, and by welding the first current collector 20 to the first pole ear 12, the connection stability between the first current collector 20 and the first pole ear 12 can be ensured. In this way, the current flow capacity between the first current collector 20 and the first pole ear 12 is guaranteed, and the extension direction of the first welding wire 21 on the first current collector 20 is not parallel to the extension direction of the first end 1211 connecting the single-piece pole ear 121 and the battery cell body 11, thereby reducing the welding energy during the welding process between the first current collector 20 and the first pole ear 12. It can pass through the adjacent single-piece pole ear 121 to hit the battery cell body 11, avoid the problem of damaging the battery cell body 11, thereby effectively improving the safety performance of the cylindrical battery.

[0024] It should be noted that, combined with Figure 3 As shown, the battery cell 10 includes a battery cell body 11 and a first pole tab 12 , and the first pole tab 12 extends from the battery cell body 11 .

[0025] like Figure 4 As shown, along the radial direction of the battery cell 10, the first pole tab 12 includes a plurality of single-piece pole tabs 121. The first pole tab 12 can be formed by bending and gathering the plurality of single-piece pole tabs 121, thereby ensuring the current carrying capacity of the first pole tab 12 itself. The radial direction of the battery cell 10 is the direction from the center of the battery cell 10 toward the circumferential outer surface of the battery cell 10.

[0026] like Figure 4 As shown, the single-piece pole ear 121 has a first end 1211 connected to the battery body 11. Considering that the battery cell 10 of the cylindrical battery is wound, the shape of the single-piece pole ear 121 can be roughly a circular arc segment. Accordingly, the extension direction of the first end 1211 can be basically the direction of the circular arc. The first end 1211 of the single-piece pole ear 121 is the root of the first pole ear 12. The root of the first pole ear 12 has a length dimension. The extension direction of the first end 1211 is defined as the circumferential direction of the battery body 11. The circumferential direction of the battery body 11 can be considered as the extension direction of the circumferential outer surface of the battery body 11. The first current collector 20 is welded to the first pole ear 12, thereby forming a first welding line 21 on the first current collector 20, as shown in FIG. Figure 2 shown.

[0027] Considering that when the first current collector 20 is welded to the first pole tab 12, if the extension direction of the first welding wire 21 is parallel to the extension direction of the first end 1211, the welding energy of the first current collector 20 and the first pole tab 12 has a certain probability of hitting the adjacent monolithic pole tabs 121, so that the energy may pass through the adjacent monolithic pole tabs 121 and then hit the battery cell body 11. If spot welding is adopted, multiple single points have a greater probability of penetrating the adjacent monolithic pole tabs 121. In this embodiment, the first current collector 20 and the first pole tab 12 are welded by welding wire, and the extension direction of the first end 1211 is not parallel to the extension direction of the first welding wire 21, thereby effectively reducing the probability of energy damaging the battery cell body 11, thereby effectively improving the safety performance of the cylindrical battery.

[0028] The first current collector 20 and the first electrode tab 12 can be laser welded. By making the extension direction of the first end 1211 non-parallel to the extension direction of the first welding line 21 , it is possible to avoid laser energy passing through adjacent single-piece electrode tabs 121 to damage the battery cell body 11 .

[0029] In one embodiment, Figure 4 As shown, the single-piece tab 121 has a second end 1212 away from the battery body 11 , and the extension direction of the second end 1212 is not parallel to the extension direction of the first welding wire 21 , thereby effectively avoiding the possibility of welding energy damaging the battery body 11 .

[0030] Combination Figure 4 As shown, the single-piece pole ear 121 has a first end 1211 and a second end 1212 relative to each other, the first end 1211 is connected to the battery body 11, and the second end 1212 is a free end, the extension direction of the first end 1211 is not parallel to the extension direction of the first welding wire 21, and the extension direction of the second end 1212 is not parallel to the extension direction of the first welding wire 21, thereby effectively reducing the probability of welding energy passing through the adjacent single-piece pole ear 121 to hit the battery body 11, thereby improving the safe use performance of the cylindrical battery.

[0031] The second end 1212 of the monolithic pole tab 121 is the end of the first pole tab 12 away from its root, the end of the first pole tab 12 has a length dimension, and the extension direction of the second end 1212 is also defined as the circumferential direction of the battery cell body 11. Considering that the size of the monolithic pole tab 121 is relatively thin, the first end 1211 and the second end 1212 of the monolithic pole tab 121 have an obvious length dimension direction, and the length dimension directions of the first end 1211 and the second end 1212 of the monolithic pole tab 121 are both interpreted as the circumferential direction of the battery cell body 11.

[0032] Considering that the extension direction of the first end 1211 is parallel to the extension direction of the second end 1212, it is not only convenient to form the battery cell 10, but also can effectively reduce the probability of welding energy passing through the adjacent single-piece tab 121 to hit the battery cell body 11, thereby avoiding affecting the safety performance of the battery cell 10. The extension direction of the first end 1211 can be an arc direction, and the extension direction of the second end 1212 can be an arc direction.

[0033] In one embodiment, Figure 4 As shown, along the radial direction of the battery cell 10, there is a gap area 122 between two adjacent single-piece tabs 121, and the extension direction of the gap area 122 is not parallel to the extension direction of the first welding line 21, thereby avoiding that during the welding process of the first current collector 20 and the first tab 12, for example, when the first current collector 20 and the first tab 12 are laser welded, the probability of laser energy passing through the gap area 122 and hitting the battery cell body 11 is effectively reduced, thereby reducing the probability of damage to the battery cell body 11, thereby improving the safe use performance of the cylindrical battery.

[0034] The first electrode tab 12 is formed by gathering a plurality of single-piece electrode tabs 121. After the plurality of single-piece electrode tabs 121 are gathered, even if two adjacent single-piece electrode tabs 121 are in contact, there will be a certain gap area 122. The size of the gap area 122 is not limited. The extension direction of the gap area 122 is not parallel to the extension direction of the first welding wire 21, which can effectively reduce the probability of welding energy passing through the gap area 122 and hitting the battery body 11.

[0035] The extending direction of the gap region 122 between two adjacent single-piece tabs 121 may be an arc direction.

[0036] In one embodiment, along the circumferential direction of the battery cell 10, there is a gap area 122 between two adjacent single-piece tabs 121, and the extension direction of the gap area 122 is not parallel to the extension direction of the first welding line 21, thereby avoiding that during the welding process of the first current collector 20 and the first pole tab 12, for example, when the first current collector 20 and the first pole tab 12 are laser welded, the probability of laser energy passing through the gap area 122 and hitting the battery cell body 11 is effectively reduced, thereby reducing the probability of damage to the battery cell body 11, thereby improving the safe use performance of the cylindrical battery.

[0037] Combination Figure 5As shown, there is a gap area 122 between two adjacent single-piece pole ears 121 on the same circle, that is, along the circumferential direction of the battery cell 10, there is a gap area 122 between two adjacent single-piece pole ears 121, and the single-piece pole ears 121 of another circle can cover the gap area 122. If the extension direction of the gap area 122 is parallel to the extension direction of the first welding wire 21, the probability of laser energy penetration will increase, which may cause damage to the battery cell 10.

[0038] The extending direction of the gap region 122 between two adjacent single-piece tabs 121 may be an arc direction.

[0039] In one embodiment, the angle between the extension direction of the first end 1211 and the extension direction of the first welding wire 21 is 30°-90°. On the basis of facilitating the formation of the first welding wire 21, the probability of the welding energy passing through the single-piece pole ear 121 and hitting the battery body 11 can also be reduced, thereby reducing the risk of damaging the battery cell 10.

[0040] The first end 1211 may extend in a curved direction, and the first welding wire 21 may extend in a straight line or a curved direction. For example, the first welding wire 21 may extend in a straight line, and the straight line and the curve may form an acute angle, thereby reducing the risk of damaging the battery cell 10 .

[0041] The angle between the extension direction of the first end 1211 and the extension direction of the first welding wire 21 can be 30°, 32°, 35°, 38°, 40°, 42°, 45°, 48°, 50°, 52°, 55°, 58°, 60°, 62°, 65°, 68°, 70°, 72°, 75°, 78°, 80°, 82°, 85°, 88° or 90°, etc.

[0042] In one embodiment, Figure 2 and Figure 6 As shown, the first current collector 20 includes a first region 22 , and a first welding line 21 is formed on the first region 22 , which can not only ensure the current flow capacity of the first region 22 and the first electrode tab 12 , but also facilitate welding of the first region 22 and the first electrode tab 12 .

[0043] Among them, combined Figure 6As shown, along the radial direction of the battery cell 10, the first area 22 has a first arc end 221 and a second arc end 222 relative to each other, and a line connecting the center point of the first arc end 221 and the center point of the second arc end 222 forms a median line, and the median line is perpendicular to the first welding line 21, so as to effectively control the angle between the extension direction of the first end 1211 and the extension direction of the first welding line 21, thereby reducing the probability of the welding energy passing through the gap area 122 and hitting the battery cell body 11 during the welding process of the first current collector 20 and the first pole ear 12, thereby reducing the probability of damage to the battery cell body 11, thereby improving the safe use performance of the cylindrical battery.

[0044] In one embodiment, the first current collector 20 includes a first area 22, and the first welding line 21 is formed on the first area 22; wherein, along the radial direction of the battery cell 10, the first area 22 has a first arc end 221 and a second arc end 222 relative to each other, and the central angle of at least one of the first arc end 221 and the second arc end 222 is 30°-150°, which can not only effectively control the size of the first area 22 and facilitate the welding connection between the first area 22 and the first pole ear 12, but also effectively control the current flow capacity of the first area 22 and the first pole ear 12, thereby improving the safe use performance of the cylindrical battery.

[0045] The central angle of at least one of the first arc end 221 and the second arc end 222 can be 30°, 32°, 35°, 38°, 40°, 42°, 45°, 48°, 50°, 52°, 55°, 58°, 60°, 62°, 65°, 68°, 70°, 72°, 75°, 78°, 80°, 82°, 85°, 88°, 90°, 92°, 95°, 98°, 100°, 102°, 105°, 108°, 110°, 112°, 115°, 118°, 120°, 122°, 125°, 128°, 130°, 132°, 135°, 138°, 140°, 142°, 145°, 148° or 150°, etc.

[0046] In one embodiment, the center angle of the first arc end 221 is equal to the center angle of the second arc end 222, which not only facilitates the forming of the first region 22, but also facilitates the forming of the first welding wire 21, thereby improving the safety performance of the cylindrical battery.

[0047] In one embodiment, there are multiple first welding wires 21, which can not only ensure the connection stability between the first region 22 and the first electrode tab 12, but also ensure reliable current flow capacity between the first region 22 and the first electrode tab 12. There can be two first welding wires 21, or there can be more than two first welding wires 21.

[0048] In one embodiment, the extension directions of at least two first welding lines 21 are parallel, thereby reliably controlling the forming direction of the first welding lines 21 and facilitating the welding of the first region 22 and the first tab 12 , which can improve the manufacturing efficiency of the cylindrical battery to a certain extent.

[0049] The extension direction of the first welding wire 21 may be a straight line, the extension directions of the plurality of first welding wires 21 may all be straight lines, and the extension directions of the first welding wires 21 may all be consistent, thereby making the extension directions of the plurality of first welding wires 21 parallel.

[0050] In one embodiment, Figure 6 As shown, the first current collector 20 includes a first area 22, and the first welding wire 21 is formed on the first area 22; wherein, along the radial direction of the battery cell 10, the first area 22 has a first arc end 221 and a second arc end 222 relative to each other, and the arc length of the first arc end 221 is smaller than the arc length of the second arc end 222, which can not only adapt to the connection between the first current collector 20 and the first pole ear 12, but also ensure the distribution of the controlled resistance during the operation of the battery, thereby ensuring the uniformity of the current, thereby improving the safe use performance of the battery.

[0051] In one embodiment, the length of the first welding wire 21 closest to the first arc end 221 among the multiple first welding wires 21 is less than the length of the first welding wire 21 closest to the second arc end 222, thereby making it possible to reasonably utilize the size of the first region 22 and ensure that the multiple first welding wires 21 have a reasonable length, thereby ensuring the connection capability between the first region 22 and the first pole tab 12 and avoiding damage to the battery cell body 11 during welding, thereby improving the safety performance of the cylindrical battery.

[0052] In one embodiment, the ratio of the length of the first welding wire 21 closest to the first arc end 221 among the multiple first welding wires 21 to the arc length of the first arc end 221 is 0.46-1.5, and / or, the ratio of the length of the first welding wire 21 closest to the second arc end 222 among the multiple first welding wires 21 to the arc length of the second arc end 222 is 0.16-0.7, which can not only ensure the welding quality between the first region 22 and the first pole ear 12, but also avoid the welding energy exceeding the first region 22 and hitting other positions during the welding process, and can also ensure that there is a reliable flow area between the first region 22 and the first pole ear 12, thereby improving the safe use performance of the cylindrical battery.

[0053] After the first current collector 20 is installed, assembly tolerances cannot be ruled out. If the ratio of the length of the first welding wire 21 closest to the first arc end 221 among the multiple first welding wires 21 to the arc length of the first arc end 221 is too large, and / or the ratio of the length of the first welding wire 21 closest to the second arc end 222 among the multiple first welding wires 21 to the arc length of the second arc end 222 is too large, when the first region 22 is laser welded to the first pole ear 12, the welding wire is likely to exceed the first current collector 20 and hit other positions, which is likely to damage other structures.

[0054] The ratio of the length of the first welding wire 21 closest to the first arc end 221 among the plurality of first welding wires 21 to the arc length of the first arc end 221 may be 0.46, 0.47, 0.48, 0.5, 0.52, 0.54, 0.55, 0.57, 0.58, 0.6, 0.62, 0.64, 0.65, 0.68, 0.69, 0.7, 0.72, 0.74, 0.75, 0.78, 0.8, 0.82, 0.84, 0.85, 0.88, 0.9, 0.92, 0.94, 0.95, 0.98, 1, 1.02, 1.04, 1.05, 1.08, 1.1, 1.12, 1.14, 1.15, 1.18, 1.2, 1.22, 1.24, 1.25, 1.28, 1.3, 1.32, 1.34, 1.35, 1.38, 1.4, 1.42, 1.44, 1.45, 1.48 or 1.5, etc.

[0055] The ratio of the length of the first welding wire 21 closest to the second arc end 222 among the multiple first welding wires 21 to the arc length of the second arc end 222 is 0.16, 0.17, 0.18, 0.2, 0.22, 0.24, 0.25, 0.27, 0.28, 0.3, 0.32, 0.34, 0.35, 0.37, 0.38, 0.4, 0.42, 0.44, 0.45, 0.47, 0.48, 0.5, 0.52, 0.54, 0.55, 0.57, 0.58, 0.6, 0.62, 0.64, 0.65, 0.68, 0.69 or 0.7, etc.

[0056] In one embodiment, the ratio of the spacing between two adjacent first welding wires 21 to the minimum distance between the first arc end 221 and the second arc end 222 is 0.03-0.2, which can not only ensure the number of first welding wires 21 and improve the current flow capacity between the first area 22 and the first pole ear 12, but also avoid the welding energy during the welding process affecting the safety performance of the battery cell 10.

[0057] The ratio of the spacing between two adjacent first welding wires 21 to the minimum distance between the first arc end 221 and the second arc end 222 is too large, the multiple first welding wires 21 are relatively loose, and the flow of current between the first region 22 and the first pole tab 12 is small. The ratio of the spacing between two adjacent first welding wires 21 to the minimum distance between the first arc end 221 and the second arc end 222 is too small, the first welding wires 21 formed during the welding process are relatively dense, and the energy generated during the welding process is relatively dense, which will affect the quality of the battery cell 10 and easily cause damage to the battery cell 10.

[0058] The ratio of the spacing between two adjacent first welding lines 21 to the minimum distance between the first arc end 221 and the second arc end 222 may be 0.03, 0.04, 0.05, 0.08, 0.1, 0.11, 0.12, 0.14, 0.15, 0.18 or 0.2, etc.

[0059] In one embodiment, the shortest distance between the first welding wire 21 closest to the first arc end 221 and the first arc end 221 is 0.5mm-6mm, thereby avoiding affecting the capacity of the battery cell 10 and avoiding the welding energy from damaging the battery cell body 11 during the welding process.

[0060] The shortest distance between the first welding wire 21 closest to the first arc end 221 among the multiple first welding wires 21 and the first arc end 221 is too large, the welding area of ​​the inner ring part of the first pole ear 12 is insufficient, and the overcurrent of the pole piece close to the winding head is difficult to meet, which will cause the internal resistance of the entire battery to increase, the polarization to increase, and the capacity cannot be fully utilized. The shortest distance between the first welding wire 21 closest to the first arc end 221 among the multiple first welding wires 21 and the first arc end 221 is too small, the requirement for assembly concentricity is high, and the laser is easy to hit the battery body 11 during welding.

[0061] The shortest distance between the first welding wire 21 closest to the first arc end 221 among the multiple first welding wires 21 and the first arc end 221 can be 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.55mm, 1.6mm, 1.7mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.7mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.7mm, 3.8mm, 4mm, 4.2mm, 4.5mm, 4.7mm, 4.8mm, 5mm, 5.2mm, 5.5mm, 5.7mm, 5.8mm or 6mm, etc.

[0062] In one embodiment, the ratio of the thickness of the first region 22 to the total length of the plurality of first welding wires 21 is 0.0025-0.01, and the current carrying capacity of the first region 22 and the first electrode tab 12 can be ensured while controlling the welding time of the first region 22 and the first electrode tab 12 .

[0063] The thicker the thickness of the first region 22 is, the longer the welding time required to achieve the same welding wire length under the same welding power. To improve production efficiency and reduce welding time, it is necessary to reduce the thickness of the first region 22 or reduce the welding wire length. However, reducing the thickness of the first region 22 will lead to reduced strength and heat resistance, and reducing the welding wire length will lead to the problem of not meeting the flow area. To achieve higher production efficiency, a smaller thickness of the first region 22 or a smaller welding wire length is required. However, to take both strength and flow into account at the same time, it is necessary to control the ratio of the thickness of the first region 22 to the total length of the plurality of first welding wires 21. If the ratio of the thickness of the first region 22 to the total length of the plurality of first welding wires 21 is too large, the thickness of the first region 22 is large and the total length of the plurality of first welding wires 21 is too small, and the flow is not met. If the ratio of the thickness of the first region 22 to the total length of the plurality of first welding wires 21 is too small, the thickness of the first region 22 is small and the total length of the plurality of first welding wires 21 is too large, and the strength is not met.

[0064] The ratio of the thickness of the first region 22 to the total length of the plurality of first welding wires 21 may be 0.0025, 0.0028, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.0095 or 0.01, etc.

[0065] In one embodiment, the thickness of the first region 22 is 0.2 mm-0.8 mm, thereby ensuring the structural strength of the first region 22 and enabling the first region 22 to have a reliable flow capacity.

[0066] The thickness of the first region 22 may be 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm or 0.8 mm, etc.

[0067] In one embodiment, the total length of the plurality of first welding wires 21 is 10 mm to 80 mm. On the basis of controlling the flow capacity between the first region 22 and the first electrode tab 12 , the welding efficiency can also be effectively controlled to improve the manufacturing efficiency of the cylindrical battery.

[0068] The total length of the plurality of first welding wires 21 may be 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 18 mm, 19 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 48 mm, 50 mm, 52 mm, 54 mm, 58 mm, 60 mm, 61 mm, 62 mm, 63 mm, 64 mm, 65 mm, 66 mm, 68 mm, 69 mm, 70 mm, 71 mm, 72 mm, 73 mm, 74 mm, 75 mm, 76 mm, 78 mm, 79 mm or 80 mm, etc.

[0069] It should be noted that the total length of the plurality of first welding wires 21 is the sum of the lengths of the plurality of first welding wires 21 .

[0070] In one embodiment, Figure 4 and Figure 6 As shown, the battery cell 10 also includes a second pole tab 13, and the first pole tab 12 and the second pole tab 13 extend from the same end of the battery cell body 11, thereby effectively controlling the height of the battery cell 10 and improving the space utilization of the battery housing 40, thereby improving the energy density of the cylindrical battery.

[0071] In one embodiment, Figure 2 As shown, the battery also includes a second current collector 30, which is welded to the second pole ear 13, and a second welding wire 31 is formed on the second current collector 30; wherein, the extension direction of the first welding wire 21 is parallel to the extension direction of the second welding wire 31, on the basis of ensuring the welding quality, the welding efficiency can also be improved, thereby improving the manufacturing efficiency of the cylindrical battery.

[0072] One of the first electrode tab 12 and the second electrode tab 13 may be a positive electrode tab, and the other may be a negative electrode tab. One of the first current collector 20 and the second current collector 30 may be a positive electrode current collecting disc, and the other may be a negative electrode current collecting disc.

[0073] When welding the first current collector 20 to the first pole tab 12, and the second current collector 30 to the second pole tab 13, it is considered that the parallel first welding line 21 and the second welding line 31 are not easy to interfere. To facilitate the positioning of the equipment, one galvanometer can be used for simultaneous welding, or two galvanometers can be used for simultaneous welding, one inside and one outside, or one galvanometer can weld one pole first, turn a circle, and then weld the other pole at the same angle. In short, it is not easy to interfere between welding the positive pole tab and the negative pole tab, and the galvanometer angle does not need to be adjusted, which is convenient for quick assembly.

[0074] It should be noted that the first pole tab 12 and the second pole tab 13 can extend from opposite ends of the battery body 11, which can not only make the electron transmission path shortest, the transmission rate fast, and the heat generation low, thereby improving the safety performance of the battery.

[0075] In one embodiment, Figure 1 As shown, the cylindrical battery also includes a battery case 40 and a pole assembly 50, the pole assembly 50 is arranged on the battery case 40, the battery cell 10, the first current collector 20 and the second current collector 30 are all arranged in the battery case 40, one of the first current collector 20 and the second current collector 30 can be electrically connected to the battery case 40, and the other can be electrically connected to the pole assembly 50.

[0076] Alternatively, there may be two pole assemblies 50 , both of which are disposed on the battery housing 40 , and the first current collector 20 and the second current collector 30 may be electrically connected to the two pole assemblies 50 , respectively.

[0077] In one embodiment, the first welding wire 21 and the second welding wire 31 are symmetrically arranged, which not only facilitates the molding of the first welding wire 21 and the second welding wire 31 and improves the manufacturing efficiency of the cylindrical battery, but also ensures the safe use performance of the cylindrical battery.

[0078] For example, the first welding wire 21 and the second welding wire 31 can be symmetrically arranged about the center line of the end face of the battery cell body 11. For example, the end face of the battery cell body 11 is a circular surface, and the circular surface has a center line, and the center line divides the circular surface into two semicircles, and the first welding wire 21 and the second welding wire 31 can be symmetrically arranged about the center line of the circular surface.

[0079] In one embodiment, Figure 2 and Figure 6 As shown, the first current collector 20 includes a first area 22, the first welding line 21 is formed on the first area 22, and along the radial direction of the battery cell 10, the first area 22 has a first arc end 221 and a second arc end 222 relative to each other, the second current collector 30 includes a second area 32, along the radial direction of the battery cell 10, the second area 32 has a third arc end 321 and a fourth arc end 322 relative to each other, and the second welding line 31 is formed on the second area 32; wherein, the extension direction of the midline of the first area 22 coincides with the extension direction of the midline of the second area 32, which facilitates the rapid assembly of the first current collector 20 and the second current collector 30, while reducing the probability of the welding laser hitting the battery cell body 11 to a minimum, thereby ensuring the safety performance of the battery cell 10.

[0080] The first region 22 has a first arc end 221 and a second arc end 222 opposite to each other, and a line connecting the center point of the first arc end 221 and the center point of the second arc end 222 forms a median line of the first region 22. Correspondingly, the second region 32 may have a third arc end 321 and a fourth arc end 322, and a line connecting the center point of the third arc end 321 and the center point of the fourth arc end 322 forms a median line of the second region 32.

[0081] In one embodiment, the extension direction of the first welding wire 21 is a straight line, so that the formation of the first welding wire 21 can be facilitated and the forming efficiency of the first welding wire 21 can be improved.

[0082] In one embodiment, the product of the length of a single first welding line 21 and the weld width of a single first welding line 21 is 1 mm. 2 -5mm 2 , thereby ensuring the connection strength between the first current collecting member 20 and the first electrode tab 12 , and also ensuring the current flow capacity between the first current collecting member 20 and the first electrode tab 12 .

[0083] The product of the length of a single first welding line 21 and the weld width of a single first welding line 21 may be 1 mm. 2 , 1.2mm 2 , 1.3mm 2 , 1.4mm 2 , 1.5mm 2 , 1.6mm 2 , 1.7mm 2 , 1.8mm 2 , 1.9mm 2 , 2mm 2 , 2.2mm 2 , 2.3mm 2 , 2.4mm 2 , 2.5mm 2 , 2.6mm 2 , 2.7mm 2 , 2.8mm 2 , 2.9mm 2 , 3mm 2 , 3.2mm 2 、3.3mm 2 、3.4mm 2 , 3.5mm 2 、3.6mm 2 、3.7mm 2 、3.8mm 2 、3.9mm 2 , 4mm 2 , 4.2mm 2 , 4.3mm 2 , 4.4mm2 , 4.5mm 2 , 4.6mm 2 , 4.7mm 2 , 4.8mm 2 , 4.9mm 2 or 5mm 2 etc.

[0084] In one embodiment, in combination Figure 1 , Figure 2 as well as Figure 6 As shown, the first current collector 20 includes a first area 22, and the first welding wire 21 is formed on the first area 22. Along the radial direction of the battery cell 10, the first area 22 has a first arc end 221 and a second arc end 222 relative to each other. The cylindrical battery also includes: a pole assembly 50, and the first current collector 20 also includes a pole connection area 23, which is connected to the first arc end 221, and the pole connection area 23 is connected to the pole assembly 50, thereby allowing the first pole ear 12 to be electrically connected to the pole assembly 50 through the first current collector 20.

[0085] The first current collector 20 includes a first area 22 and a pole connection area 23, the circumferential outer edge of the pole connection area 23 can be basically a circle, the pole connection area 23 can be located at the center of the battery, and the pole assembly 50 can be arranged at the center of the battery housing 40, thereby facilitating the connection between the pole assembly 50 and the pole connection area 23, the pole assembly 50 and the pole connection area 23 can be welded, or the pole assembly 50 and the pole connection area 23 can be riveted, or the pole assembly 50 and the pole connection area 23 can be electrically connected by conductive glue.

[0086] In one embodiment, Figure 1 and Figure 2 As shown, the battery also includes a second current collector 30 and a battery shell 40, the battery cell 10, the first current collector 20 and the second current collector 30 are all arranged in the battery shell 40, and the pole assembly 50 is arranged on the battery shell 40; the second current collector 30 includes a second area 32 and a shell connection area 33, along the radial direction of the battery cell 10, the second area 32 has a third arc end 321 and a fourth arc end 322 relative to each other, the shell connection area 33 is connected to the third arc end 321, the second area 32 is welded to the second pole ear 13, and the shell connection area 33 is connected to the battery shell 40, that is, the pole assembly 50 and the battery shell 40 can be used as two electrode lead-out terminals of the battery, which can not only reduce the number of components used in the battery, but also facilitate the connection between the bus and the battery when the batteries are subsequently grouped, that is, the battery shell 40 is used as the electrode lead-out terminal, which can increase the selectivity of the connection area of ​​the bus.

[0087] The second current collector 30 includes a second region 32 and a shell connection region 33. The shell connection region 33 may be substantially a circular ring structure, thereby ensuring the connection strength with the battery shell 40. The shell connection region 33 and the battery shell 40 may be connected by welding.

[0088] Combination Figure 1 As shown, the battery housing 40 may include a cover plate and a housing member. A pole assembly 50 may be arranged on the cover plate. The pole assembly 50 may be electrically connected to the first current collector 20, and the cover plate may be electrically connected to the second current collector 30. At this time, the pole assembly 50 and the cover plate may be insulated, thereby ensuring the insulation protection capability between the cover plate and the pole assembly 50.

[0089] It should be noted that along the radial direction of the battery cell 10, the first region 22 has a relative first arc end 221 and a second arc end 222, and along the radial direction of the battery cell 10, the second region 32 has a relative third arc end 321 and a fourth arc end 322. The first arc end 221, the second arc end 222, the third arc end 321 and the fourth arc end 322 can basically be arc segments, and manufacturing errors within a controllable range and slight changes in the structural form can be considered to be included in the range of the arc segment.

[0090] It should be noted that the cylindrical battery includes a cell and an electrolyte, which is the smallest unit capable of performing electrochemical reactions such as charge / discharge. A cell refers to a unit formed by winding or laminating a stacked portion, which includes a positive electrode sheet, a negative electrode sheet, and a separator. The cell 10 includes a positive electrode sheet, a negative electrode sheet, and a separator, and the separator provides insulation protection for the positive electrode sheet and the negative electrode sheet.

[0091] An embodiment of the utility model further provides a battery pack, comprising the above-mentioned cylindrical battery.

[0092] The battery pack of one embodiment of the utility model includes a cylindrical battery, the cylindrical battery includes a battery cell 10 and a first current collector 20, the battery cell 10 and the first current collector 20 are electrically connected, the battery cell 10 includes a battery cell body 11 and a first pole ear 12 extending from the battery cell body 11, the first pole ear 12 is formed by gathering a plurality of single-piece pole ears 121, thereby ensuring the overall current capacity of the first pole ear 12, and by welding the first current collector 20 to the first pole ear 12, the first current collector 20 and the first pole ear 12 can be ensured. The connection stability is improved, thereby ensuring the current flow capacity between the first current collector 20 and the first pole ear 12, and the extension direction of the first welding wire 21 on the first current collector 20 is not parallel to the extension direction of the first end 1211 connecting the single-piece pole ear 121 and the battery cell body 11, thereby reducing the welding energy during the welding process of the first current collector 20 and the first pole ear 12 from passing through the adjacent single-piece pole ear 121 to the battery cell body 11, avoiding the problem of damaging the battery cell body 11, thereby effectively improving the safe use performance of the battery pack.

[0093] In one embodiment, the battery pack is a battery module or a battery pack.

[0094] The battery pack includes a plurality of batteries and a box body, and the box body is used to fix the plurality of batteries.

[0095] It should be noted that the battery pack includes a battery, and the battery may be multiple, and the multiple batteries are arranged in the box. Among them, the multiple batteries can be installed in the box after forming a battery module. Alternatively, the multiple batteries can be directly arranged in the box, that is, there is no need to group the multiple batteries, and the box is used to fix the multiple batteries.

[0096] Those skilled in the art will readily come up with other embodiments of the present disclosure after considering the specification and practicing the utility model disclosed herein. The present disclosure is intended to cover any variation, use or adaptation of the present utility model, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and example embodiments are to be regarded as exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

[0097] It should be understood that the present disclosure is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from its scope. The scope of protection of the present disclosure is limited only by the appended claims.

Claims

1. A cylindrical battery, characterized in that: include: A battery cell (10), the battery cell (10) comprising a battery cell body (11) and a first pole lug (12), the first pole lug (12) extending from the battery cell body (11), and along the radial direction of the battery cell (10), the first pole lug (12) comprising a plurality of single-piece pole lugs (121); A first current collecting member (20), the first current collecting member (20) being connected to the first electrode tab (12) by welding, and a first welding line (21) being formed on the first current collecting member (20); The single-piece electrode tab (121) has a first end (1211) connected to the battery cell body (11), and an extension direction of the first end (1211) is not parallel to an extension direction of the first welding wire (21).

2. The cylindrical battery according to claim 1, characterized in that: The single-piece pole ear (121) has a second end (1212) away from the battery core body (11), and the extension direction of the second end (1212) is not parallel to the extension direction of the first welding wire (21).

3. The cylindrical battery according to claim 1, characterized in that: Along the radial direction of the battery core (10), there is a gap region (122) between two adjacent single-piece tabs (121), and the extension direction of the gap region (122) is not parallel to the extension direction of the first welding line (21); And / or, along the circumferential direction of the battery core (10), there is a gap area (122) between two adjacent single-piece tabs (121), and the extension direction of the gap area (122) is not parallel to the extension direction of the first welding line (21).

4. The cylindrical battery according to claim 1, characterized in that: The angle between the extension direction of the first end (1211) and the extension direction of the first welding line (21) is 30°-90°.

5. The cylindrical battery according to claim 1, characterized in that: The first current collecting member (20) comprises a first region (22), and the first welding line (21) is formed on the first region (22); Wherein, along the radial direction of the battery core (10), the first region (22) has a first arc end (221) and a second arc end (222) opposite to each other, and a line connecting the center point of the first arc end (221) and the center point of the second arc end (222) forms a midline, and the midline is perpendicular to the first welding line (21).

6. The cylindrical battery according to claim 1, characterized in that: The first current collecting member (20) comprises a first region (22), and the first welding line (21) is formed on the first region (22); Wherein, along the radial direction of the battery core (10), the first region (22) has a first arc end (221) and a second arc end (222) opposite to each other, and a central angle of at least one of the first arc end (221) and the second arc end (222) is 30°-150°.

7. The cylindrical battery according to claim 6, characterized in that: The center angle of the first arc end (221) is equal to the center angle of the second arc end (222).

8. The cylindrical battery according to claim 1, characterized in that: There are multiple first welding wires (21).

9. The cylindrical battery according to claim 8, characterized in that: The extension directions of at least two of the first welding lines (21) are parallel.

10. The cylindrical battery according to claim 8, characterized in that: The first current collecting member (20) comprises a first region (22), and the first welding line (21) is formed on the first region (22); Wherein, along the radial direction of the battery core (10), the first region (22) has a first arc end (221) and a second arc end (222) opposite to each other, and the arc length of the first arc end (221) is smaller than the arc length of the second arc end (222).

11. The cylindrical battery according to claim 10, characterized in that: Among the plurality of first welding wires (21), the length of the first welding wire (21) closest to the first arc end (221) is smaller than the length of the first welding wire (21) closest to the second arc end (222).

12. The cylindrical battery according to claim 10, characterized in that: The ratio of the length of the first welding wire (21) closest to the first arc end (221) among the plurality of first welding wires (21) to the arc length of the first arc end (221) is 0.46-1.5, and / or the ratio of the length of the first welding wire (21) closest to the second arc end (222) among the plurality of first welding wires (21) to the arc length of the second arc end (222) is 0.16-0.

7.

13. The cylindrical battery according to claim 10, characterized in that: The ratio of the spacing between two adjacent first welding lines (21) to the minimum distance between the first circular arc end (221) and the second circular arc end (222) is 0.03-0.

2.

14. The cylindrical battery according to claim 10, characterized in that: The shortest distance between the first welding wire (21) closest to the first arc end (221) among the plurality of first welding wires (21) and the first arc end (221) is 0.5 mm to 6 mm.

15. The cylindrical battery according to claim 10, characterized in that: The ratio of the thickness of the first region (22) to the total length of the first welding wires (21) is 0.0025-0.

01.

16. The cylindrical battery according to claim 15, characterized in that: The thickness of the first region (22) is 0.2 mm-0.8 mm, and / or the total length of the plurality of first welding wires (21) is 10 mm-80 mm.

17. The cylindrical battery according to any one of claims 1 to 16, characterized in that: The battery cell (10) further comprises a second pole lug (13), wherein the first pole lug (12) and the second pole lug (13) extend from the same end of the battery cell body (11).

18. The cylindrical battery according to claim 17, characterized in that: The battery further comprises a second current collecting member (30), the second current collecting member (30) being connected to the second electrode tab (13) by welding, and a second welding wire (31) being formed on the second current collecting member (30); Wherein, the extension direction of the first welding line (21) is parallel to the extension direction of the second welding line (31).

19. The cylindrical battery according to claim 18, characterized in that: The first welding line (21) and the second welding line (31) are arranged symmetrically.

20. The cylindrical battery according to claim 18, characterized in that: The first current collecting member (20) comprises a first region (22), the first welding wire (21) is formed on the first region (22), and along the radial direction of the battery cell (10), the first region (22) has a first arc end (221) and a second arc end (222) opposite to each other; the second current collecting member (30) comprises a second region (32), along the radial direction of the battery cell (10), the second region (32) has a third arc end (321) and a fourth arc end (322) opposite to each other, and the second welding wire (31) is formed on the second region (32); The extension direction of the median line of the first region (22) coincides with the extension direction of the median line of the second region (32).

21. The cylindrical battery according to any one of claims 1 to 16, characterized in that: The extension direction of the first welding line (21) is a straight line, and / or the product of the length of a single first welding line (21) and the weld width of a single first welding line (21) is 1 mm. 2 -5mm 2 .

22. The cylindrical battery according to any one of claims 1 to 16, characterized in that: The first current collector (20) comprises a first region (22), the first welding line (21) is formed on the first region (22), and along the radial direction of the battery cell (10), the first region (22) has a first arc end (221) and a second arc end (222) opposite to each other, and the cylindrical battery further comprises: The first current collector (20) further comprises a pole connection region (23), wherein the pole connection region (23) is connected to the first arc end (221), and the pole connection region (23) is connected to the pole assembly (50).

23. The cylindrical battery according to claim 22, characterized in that: The battery further comprises a second current collector (30) and a battery casing (40); the battery cell (10), the first current collector (20) and the second current collector (30) are all arranged in the battery casing (40); and the pole assembly (50) is arranged on the battery casing (40); The second current collector (30) comprises a second region (32) and a shell connection region (33); along the radial direction of the battery cell (10), the second region (32) has a third arc end (321) and a fourth arc end (322) opposite to each other; the shell connection region (33) is connected to the third arc end (321); the battery cell (10) further comprises a second pole lug (13); the second region (32) is welded to the second pole lug (13); and the shell connection region (33) is connected to the battery shell (40).

Images