Battery

Abstract

The invention relates to the technical field of batteries, in particular to a battery which comprises a shell and a cylindrical roll core, the shell comprises a pole assembly, and the cylindrical roll core comprises a roll core hole; the cylindrical roll core comprises a pole piece; the pole piece comprises a pole piece body and a plurality of tabs; the tab is used for being electrically connected with the pole assembly and / or the shell; the pole piece comprises a winding head end, the pole lug comprises a first pole lug, in the length direction of the unfolded pole piece, the distance between the first pole lug and the winding head end is D1, the area of a winding core hole is S, and the range of D1 / S is between 3 and 45. According to the embodiment of the invention, the spacing and the area of the roll core hole can be comprehensively adjusted, the position of the roll core hole is prevented from being covered after the tab is turned over, and liquid injection is not influenced. When the liquid injection holes and the tabs are on the same side, the situation that the electrolyte is injected into the roll core holes directly affected by shielding of the tabs is avoided; and when the liquid injection hole and the tab are not arranged at the same end, the condition that the battery cell is infiltrated by the electrolyte in the roll core hole after the roll core hole is shielded by the tab is avoided.

Description

[0001] This application is a divisional application of the invention patent application with publication number CN202411399326.6. The application date of the original application is: 2024.10.09; the application number is: 202411399326.6; the name of the invention is: "Battery". Technical Field

[0002] The present invention relates to the technical field of batteries, and in particular to a battery. Background Art

[0003] The battery is formed by winding the positive electrode sheet, negative electrode sheet and separator according to the set number of layers and turns. After the battery is wound, a core hole will be formed. In addition, after the winding is completed, the first pole ear may block the core hole, which is not conducive to the subsequent electrolyte infiltration of the pole sheet in the core hole. Summary of the invention

[0004] In view of this, the present invention provides a battery to solve the problem that the tabs in the battery block the winding core holes, affecting the electrolyte injection and the electrolyte infiltration of the pole pieces.

[0005] In a first aspect, the present invention provides a battery, comprising:

[0006] A shell and a cylindrical winding core, wherein the shell includes a pole assembly, and the cylindrical winding core includes a winding core hole and a pole piece; the pole piece includes a pole piece body and a plurality of pole ears; the pole ears are used to be electrically connected to the pole assembly and, or, the shell;

[0007] The pole piece includes a winding head end, the pole ear includes a first pole ear, in the length direction of the pole piece after being unfolded, the distance between the first pole ear and the winding head end is D1, the area of ​​the winding core hole is S, and the range of D1 / S is between 3 and 45;

[0008] After the pole piece is unfolded, the distance between two adjacent pole ears in the first winding core layer and the adjacent winding core layer is D3, and the first winding core layer is the winding core layer closest to the winding core hole;

[0009] D3 is the minimum distance between two adjacent tabs in the first winding layer and the adjacent winding layer.

[0010] Beneficial effect: The embodiment of the present invention limits the spacing between the first pole ear and the winding head end, and limits the area of ​​the winding core hole at the same time. In this way, the spacing and the area of ​​the winding core hole can be adjusted comprehensively. When the area of ​​the winding core hole is larger, the spacing also needs to be larger, so as to avoid covering the position of the winding core hole and affecting the injection after the pole ear is folded. When the injection hole and the pole ear are on the same side, the pole ear is prevented from blocking the electrolyte injection into the winding core hole; when the injection hole and the pole ear are not set at the same end, the pole ear is prevented from blocking the winding core hole and affecting the electrolyte in the winding core hole from infiltrating the battery cell. In addition, the ratio between the spacing and the area cannot be too small. If it is too small, the spacing between the first pole ear and the winding head end will be too small, and the area of ​​the winding core hole will be too large. Then, after the pole ear is folded, it is easy to block the winding core hole and affect the injection. If it is too large, the spacing between the pole ear and the winding head end is too far. Since the pole ear mainly bears the overcurrent, it is equivalent to a part of the pole sheet without the pole ear, resulting in poor overcurrent capacity of this part. Therefore, limiting the distance between the first pole ear and the winding head end to within this numerical range can ensure the current capacity of the pole piece. Furthermore, it is also necessary to control the size of the winding core hole, and the area of ​​the winding core hole also needs to be within a certain range. If it is too small, it will be detrimental to electrolyte injection and exhaust. In order to avoid the pole ear blocking the winding core hole, the distance between the first pole ear and the winding head end is increased, resulting in poor current capacity of the pole piece. Therefore, on this basis, it is necessary to control the distance between the first pole ear and the adjacent pole ear to avoid poor current capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 Schematic diagram of the overall structure of the winding core in an embodiment of the present invention;

[0013] Figure 2 is a top view of a winding core according to an embodiment of the present invention;

[0014] Figure 3 is a cross-sectional view of a battery in an embodiment of the present invention;

[0015] Figure 4 It is a schematic diagram showing that the liquid injection hole and the electrode tab are arranged on the same side in an embodiment of the present invention;

[0016] Figure 5 This is a schematic diagram of an embodiment of the present invention in which the injection hole and the electrode tab are arranged on opposite sides;

[0017] Figure 6Schematic diagram of a pole piece after unfolding in an embodiment of the present invention;

[0018] Figure 7 It is a schematic diagram of marking D3 after the pole piece is unfolded in an embodiment of the present invention.

[0019] Description of reference numerals:

[0020] 1. Cylindrical winding core; 2. Pole piece; 3. Winding core hole; 4. Positive electrode piece; 5. Negative electrode piece; 6. Winding start end; 7. First pole ear; 8. Second pole ear; 9. Winding end end; 10. Third pole ear; 11. Fourth pole ear; 12. Liquid injection hole. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0022] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal communication of two components, it can be a wireless connection, or it can be a wired connection. For ordinary workers in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0025] The battery is a cylindrical core 1 formed by winding the positive electrode sheet 4, the negative electrode sheet 5 and the separator according to the set number of layers and turns. The battery includes a cylindrical core 1 and a shell, and the shell can be circular; or it can also be other shapes, such as a hexagonal prism. The shell material can be steel, aluminum, etc. Specifically, it can be stainless steel, nickel-plated steel, aluminum alloy, aluminum-manganese alloy, etc. Of course, other materials can also be used. This is just an example, but it is not limited to this. It can achieve the same technical effect.

[0026] The cylindrical winding core 1 includes a pole piece 2, and a winding core hole 3 is formed in the pole piece 2 after winding. In the length direction after the pole piece 2 is unfolded, the first pole ear is usually a certain distance away from the winding head end 6 of the pole piece 2. The winding head end 6 is the very beginning of the winding. If the first pole ear 7 is directly set at the winding head end 6, the first pole ear 7 may block the winding core hole 3 after the winding is completed. Therefore, the method adopted in this embodiment is to control the distance between the first pole ear 7 and the winding head end 6 within a certain range to prevent the first pole ear 7 from blocking the winding core hole 3 after winding. Since the pole ear mainly bears the role of overcurrent, if the distance between the first pole ear 7 and the winding head end 6 is controlled too far, the overcurrent capacity will be deteriorated, which will seriously affect the battery. If the distance between the first pole ear 7 and the winding head end 6 is controlled too close, the winding core hole 3 will still be blocked.

[0027] The present application can prevent the first pole ear 7 from blocking the winding core hole 3 and affecting the electrolyte infiltration into the battery cell by comprehensively controlling the distance between the first pole ear 7 and the winding head end 6 and the area of ​​the winding core hole 3, while ensuring the current flow capacity of the pole piece 2.

[0028] A distance D1 is provided between the first pole lug 7 and the winding head end 6. Figure 6 and Figure 7 As shown, D1 refers to the minimum distance between the first pole tab 7 and the winding head end 6. In addition, the pole tab can be rectangular or trapezoidal.

[0029] Of course, this embodiment is only an example to illustrate the specific shape of the pole ear, but it is not limited to this. Those skilled in the art can make changes according to actual conditions as long as the same technical effect can be achieved.

[0030] The area of ​​the core hole 3 is S, and the ratio between the spacing and the area is D1 / S. When D1 / S is too large, that is, D1 is too large, or S is too small, the current carrying capacity of the electrode 2 will be poor. In addition, if S is too small, it will affect the capacity of the core hole 3 to store electrolyte, which is not conducive to the subsequent electrolyte in the core hole 3 to infiltrate the electrode 2; the ratio cannot be too small, D1 is too small, or S is too large, D1 is too small, the pole ear is easy to block the core hole 3, in addition, when the area of ​​the core hole 3 is relatively large, the risk of the pole ear blocking the core hole 3 increases, affecting the electrolyte infiltration of the battery cell.

[0031] In the present application, the shell also includes an injection hole 12, and the positive ear, the negative ear and the injection hole 12 can be located on the same side or on different sides. When the positive ear, the negative ear and the injection hole 12 are located on the same side, there is a high risk that the positive ear and the negative ear block the winding core hole 3, and D1 needs to be larger, or S needs to be smaller. However, S cannot be too small, otherwise it will affect the amount of electrolyte stored in the winding core hole 3, which is not conducive to the subsequent infiltration of the electrolyte in the winding core hole 3 into the electrode 2. When the injection hole 12 and the ear are not arranged on the same side, after the ear blocks the winding core hole 3, it affects the electrolyte in the winding core hole 3 from infiltrating the battery cell.

[0032] Combine the following Figures 1 to 7 , describe the embodiments of the present invention in detail.

[0033] According to an embodiment of the present invention, on the one hand, a battery is provided, such as Figure 1 As shown, the cylindrical winding core 1 includes a winding core hole 3 and a pole piece 2. The pole piece 2 includes a pole piece body and a plurality of pole tabs. The pole tabs are used to electrically connect with the pole assembly and the housing. Of course, the pole tabs can also be electrically connected only with the pole assembly or the housing.

[0034] Further, in the embodiment of the present invention, the pole piece 2 includes a winding head end 6, the pole ear includes a first pole ear 7, and in the length direction of the pole piece 2 after being unfolded, the distance between the first pole ear 7 and the winding head end 6 is D1, the area of ​​the winding core hole 3 is S, and the range of D1 / S is between 3 and 45. Specifically, the value of D1 / S can be any value of 3, 10, 15, 20, 25, 30, 35, 40, etc., or a value between any two values.

[0035] like Figure 2 As shown, the pole piece 2 is provided with a winding head end 6 at one end close to the winding core hole 3, that is, when winding, the pole piece 2 starts winding from the winding head end 6, which is the first end of the winding. In addition, since a plurality of pole lugs are provided on the pole piece 2, the pole lug closest to the winding head end 6 is defined as the first pole lug 7.

[0036] Regarding the tab forming method, specifically, in this embodiment, the pole piece 2 includes a current collector and an active material layer, the active material layer is coated on the current collector, and the tab can be formed by cutting the current collector. It can also be, for example, a separate conductive member electrically connected to the current collector. The current collector can be aluminum or copper.

[0037] With such a configuration, the embodiment of the present invention limits the spacing between the first pole tab 7 and the winding head end 6, and at the same time limits the area of ​​the winding core hole 3. In this way, the spacing and the area of ​​the winding core hole 3 can be adjusted comprehensively. The larger the area of ​​the winding core hole 3, the larger the spacing needs to be, so as to avoid covering the position of the winding core hole 3 after the pole tab is folded, which affects the injection. When the injection hole 12 and the pole tab are on the same side, the pole tab directly affects the injection of electrolyte into the winding core hole 3. When the injection hole 12 and the pole tab are not set at the same end, the pole tab blocks the winding core hole 3, which affects the electrolyte in the winding core hole 3 from infiltrating the battery cell. When they are not set on the same side, the electrolyte needs to be injected into the winding core hole 3 from one end of the injection hole. The pole tab blocks the winding core hole 3, causing the electrolyte in the winding core hole 3 to be unable to flow out to infiltrate the battery cell. In addition, the ratio between the spacing and the area cannot be too small. If it is too small, the spacing between the first pole tab 7 and the winding head end 6 will be too small, and the area of ​​the winding core hole 3 will be too large. Then, after the pole tab is folded, it is easy to block the winding core hole 3, affecting the injection. If it is too large, the spacing between the pole tab and the winding head end 6 will be too far. Since the pole tab mainly bears the overcurrent, it is equivalent to a part of the pole piece 2 without a pole tab, causing the overcurrent capacity of this part to deteriorate. Therefore, limiting the spacing between the first pole tab 7 and the winding head end 6 within this numerical range can ensure the overcurrent capacity of the pole piece 2.

[0038] Furthermore, it is also necessary to control the size of the core hole 3, and the area of ​​the core hole 3 also needs to be within a certain range. If it is too small, it will be detrimental to the injection and exhaust of the electrolyte. Specifically, when the injection hole 12 and the pole ear are on the same side, the pole ear blocks the injection hole 12, affecting direct injection. When the injection hole 12 and the pole ear are on different sides, the pole ear blocks the core hole 3. In actual application, the pole ear may be at the top of the battery, and the injection hole 12 is at the bottom of the battery. When injecting liquid, theoretically, the side of the battery injection hole 12 facing up can avoid the problem of the pole ear blocking. But in fact, under the action of gravity, the pole ear may sag and block the injection hole 12 due to its own weight or other factors, resulting in poor electrolyte outflow. The electrolyte cannot flow out smoothly from the core hole 3 to infiltrate the end face of the battery cell, which not only affects the uniform infiltration of the internal materials of the battery, but also may bring safety hazards and reduce battery performance and life. The area range of the core hole 3 can be 0.7mm 2 Up to 80mm 2 Specifically, it can be 0.7 mm 2 , 25mm 2 , 10mm 2 , 20mm 2 , 30mm 2 , 40mm 2 , 50mm 2 、60mm 2 , 70mm 2 , 80mm 2Any value in between or any value between any two values.

[0039] Further, in an optional embodiment, as Figure 6 As shown, when the pole piece 2 is unfolded, in the plane where the pole piece 2 is located, the direction perpendicular to the winding of the pole piece 2 is defined as the height direction of the pole ear, the height of the first pole ear 7 is H, the ratio between the spacing and the height is D1 / H, and D1 / H is between 18 and 240. Specifically, the value of D1 / H can be any value of 18, 40, 80, 120, 160, 200, 240, etc. or a value between any two values.

[0040] In the embodiment of the present invention, the range of H is between 2.5 mm and 15 mm.

[0041] In this arrangement, the greater the height of the tab, the easier it is for the tab to block the winding core hole 3 after the tab is folded. Therefore, the greater the height of the tab, the larger the distance between the first tab 7 and the winding head end 6 needs to be controlled, so that after the tab is folded, the area blocking the winding core hole 3 can be reduced. In addition, the height of the first tab 7 cannot be too small, otherwise it will affect the overall flow area of ​​the first tab 7, thereby affecting the overall flow capacity of the first tab 7.

[0042] Further, in an optional embodiment, as Figure 1 As shown, the electrode sheet 2 includes a positive electrode sheet 4 and a negative electrode sheet 5 .

[0043] Specifically, in an embodiment of the present invention, along the axial direction of the winding core hole 3, the positive electrode sheet 4 is provided with a plurality of positive electrode ears on one side of the winding core hole 3, and the plurality of positive electrode ears can be arranged at intervals. For the specific interval value, those skilled in the art can adjust it according to the actual situation. This embodiment is not limited to this, and it is sufficient to achieve the same technical effect.

[0044] Similarly, along the axial direction of the winding core hole 3, the negative electrode sheet 5 is provided with a plurality of negative electrode ears on the other side of the winding core hole 3. The plurality of negative electrode ears can also be arranged at intervals, and the specific interval value can be adjusted by those skilled in the art according to the actual situation, and this embodiment is not limited thereto, as long as the same technical effect can be achieved.

[0045] Of course, in this embodiment, the positive electrode ear and the negative electrode ear can be arranged on the same side of the winding core hole 3 at the same time, or the positive electrode ear and the negative electrode ear can be arranged on opposite sides of the winding core hole 3 along the axial direction. For the specific implementation, those skilled in the art can change it according to the actual situation. This embodiment is only an example, but it is not limited to this, and it can achieve the same technical effect.

[0046] Furthermore, in the embodiments of the present invention, the two configurations of the positive electrode tab and the negative electrode tab are respectively described by way of example.

[0047] like Figure 2 As shown, when the positive electrode ear and the negative electrode ear are arranged on the same side of the winding core hole 3, after the electrode sheet 2 is unfolded, D1 is between 200 mm and 900 mm. Specifically, it can be any value among 200 mm, 300 mm, 400 mm, 500 mm, 600 mm, 700 mm, 800 mm, 900 mm, etc., or a value between any two values.

[0048] That is to say, on the same side, the distance between the positive electrode ear and the winding head end 6 of the positive electrode sheet 4 can be between 200 mm and 900 mm, and the distance between the negative electrode ear and the winding head end 6 of the negative electrode sheet 5 can be between 200 mm and 900 mm.

[0049] Furthermore, the distance between the positive electrode ear and the winding head end 6 of the positive electrode sheet 4, and the distance between the negative electrode ear and the winding head end 6 of the negative electrode sheet 5 may be consistent or inconsistent. When the distances between the positive electrode ear and the negative electrode ear and the winding head end 6 are inconsistent, the smaller distance between the positive electrode ear and the negative electrode ear and the winding head end 6 is taken as D1.

[0050] Those skilled in the art can make changes according to actual conditions.

[0051] When the positive electrode ear and the negative electrode ear are arranged on opposite sides of the winding core hole 3 along the axial direction (not shown in the figure), after the pole piece 2 is unfolded, D1 is between 150 mm and 850 mm. Specifically, it can be any value among 200 mm, 300 mm, 400 mm, 500 mm, 600 mm, 700 mm, 800 mm, 850 mm, etc., or a value between any two values.

[0052] That is to say, when the positive electrode ear and the negative electrode ear are located on both sides respectively, the distance between the positive electrode ear and the winding head end 6 of the positive electrode sheet 4 can be between 150mm and 850mm, and the distance between the negative electrode ear and the winding head end 6 of the negative electrode sheet 5 can be between 150mm and 850mm.

[0053] Similarly, the distance between the positive electrode ear and the winding head end 6 of the positive electrode sheet 4, and the distance between the negative electrode ear and the winding head end 6 of the negative electrode sheet 5, may be consistent or inconsistent. Those skilled in the art may change it according to actual conditions. When the distances between the positive electrode ear and the negative electrode ear and the winding head end 6 are inconsistent, the smaller distance between the positive electrode ear and the negative electrode ear and the winding head end 6 is taken as D1.

[0054] It should be noted that when the positive electrode tab and the negative electrode tab are arranged on the same side of the winding core hole 3, the probability of the positive electrode tab and the negative electrode tab blocking the injection hole 12 becomes greater. Therefore, the distance between the first electrode tab 7 and the winding head end 6 of the electrode sheet 2 can be larger than that on both sides, so as to avoid the first electrode tab 7 blocking the winding core hole 3.

[0055] Moreover, when the positive and negative pole ears are arranged on the same side of the winding core hole 3 at the same time, after winding, if the first pole ear 7 is too close to the head end of the pole piece 2, the insufficient isolation distance between the pole ears may lead to accidental contact and cause a short circuit, thereby causing rapid heat accumulation, battery damage and even safety problems.

[0056] Therefore, by further limiting the distance between the first electrode tab 7 and the winding head end 6, it can be ensured that there is a sufficient safety distance between the positive and negative electrode tabs even in extreme environments, such as vibration and deformation environments.

[0057] Further, in an optional embodiment, as Figure 6 As shown, when the positive electrode tab and the negative electrode tab are simultaneously arranged on the same side of the winding core hole 3, the range of H is between 2.5 mm and 12 mm. Specifically, it can be any value of 2.5 mm, 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, etc., or a value between any two values; that is, when the first electrode tab 7 is a positive electrode tab, the height range of the positive electrode tab is between 2.5 mm and 12 mm, and when the first electrode tab 7 is a negative electrode tab, the height range of the negative electrode tab is between 2.5 mm and 12 mm.

[0058] Similarly, the height of the positive electrode ear and the height of the negative electrode ear may be consistent or inconsistent. Those skilled in the art may change it according to actual conditions. When the heights of the positive electrode ear and the negative electrode ear are inconsistent, the maximum value of the two is taken as H.

[0059] When the positive electrode ear and the negative electrode ear are arranged on opposite sides of the winding core hole 3 along the axial direction (not shown in the figure), the range of H is between 3.5 mm and 15 mm, specifically, any value of 3.5 mm, 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, 13 mm, etc. or a value between any two values. In other words, the height of the positive electrode ear ranges from 3.5 mm to 13 mm, and the height of the negative electrode ear ranges from 3.5 mm to 13 mm.

[0060] Similarly, the height of the positive electrode ear and the height of the negative electrode ear may be consistent or inconsistent. Those skilled in the art may change it according to actual conditions. When the heights of the positive electrode ear and the negative electrode ear are inconsistent, the maximum value of the two is taken as H.

[0061] By configuring in this way, the heights of the positive electrode tab and the negative electrode tab are controlled within a certain range, thereby preventing the positive electrode tab and the negative electrode tab from blocking the winding core hole 3 due to their being too large.

[0062] Further, in an optional embodiment, the positive electrode tab includes a first positive electrode tab, and the first positive electrode tab is closest to the winding head end 6 of the positive electrode sheet. There is a first distance between the first positive electrode tab and the winding head end of the positive electrode sheet.

[0063] Similarly, the negative electrode lugs include a first negative electrode lug, and the first negative electrode lug is closest to the winding head end 6 of the negative electrode sheet 5. There is a second distance between the first negative electrode lug and the winding head end 6 of the negative electrode sheet 5.

[0064] Furthermore, the absolute value of the difference between the first distance and the second distance ranges from 0 mm to 50 mm. That is, when the first distance is greater than the second distance, the difference between the first distance and the second distance is between 0 mm and 50 mm; when the second distance is greater than the first distance, the difference between the second distance and the first distance is between 0 mm and 50 mm. Specifically, it can be any value of 0 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, etc., or a value between any two values.

[0065] Such a configuration achieves symmetry and manufacturing consistency for the first positive electrode ear and the first negative electrode ear, which helps to simplify the production process and improve production efficiency. In addition, in the actual manufacturing process, it is necessary to ensure that there is sufficient insulation protection between the positive and negative electrodes, and to take measures in the winding and packaging stages to prevent any potential short circuit risks.

[0066] Further, in an optional embodiment, as Figure 6 As shown, the pole piece 2 further includes a winding tail end 9, and the pole ear closest to the winding tail end 9 is the second pole ear 8. The winding tail end 9 is the end after the winding is completed.

[0067] In the length direction of the unfolded pole piece 2, a spacing D2 is provided between the second pole ear 8 and the winding tail end 9, and D2 is between 50 mm and 600 mm. Specifically, it can be any value among 50 mm, 100 mm, 200 mm, 300 mm, 400 mm, 500 mm, 600 mm, etc., or a value between any two values.

[0068] Likewise, if Figure 6 and Figure 7 As shown, D2 refers to the minimum distance between the second pole tab 8 and the winding tail end 9. In addition, the pole tab can be rectangular or trapezoidal.

[0069] Of course, this embodiment is only an example to illustrate the specific shape of the pole ear, but it is not limited to this. Those skilled in the art can make changes according to actual conditions as long as the same technical effect can be achieved.

[0070] At the same time, in the embodiment of the present invention, since there is a certain distance between the second pole ear 8 and the winding tail end 9, it is possible to avoid affecting the insulation between the pole ear and the shell due to a small distance, and to avoid affecting the overcurrent of the pole piece 2 due to a large distance.

[0071] Furthermore, in an optional embodiment, the cylindrical core 1 includes a plurality of core layers arranged in a radial direction, and some of the core layers are not provided with pole ears.

[0072] In the embodiment of the present invention, it is not necessary to provide tabs for all winding core layers. Figure 1 As shown, only a portion of the core layers may be provided with tabs, and the other portion of the core layers may not be provided with tabs. Furthermore, the core layers provided with tabs and the core layers not provided with tabs may be provided alternately, so that the tabs are distributed discontinuously. Furthermore, the second core layer is defined as the core layer farthest from the core hole 3, and among all the core layers, except for the first core layer and the second core layer, some of the core layers in the middle position are not provided with tabs.

[0073] In this embodiment, since some winding core layers are not provided with tabs, after the tabs are cut, the position connected to the pole body is processed first, and then the tabs are flattened and folded. Therefore, if all winding core layers are provided with tabs, the tabs will be too thick, increasing the difficulty of folding.

[0074] Further, in an optional embodiment, there is a winding core layer without a pole ear, and in the two third and fourth core layers adjacent to the winding core layer without a pole ear, both of which are provided with pole ears, the third pole ear 10 is arranged in the third winding core layer, and the fourth pole ear 11 is arranged in the fourth winding core layer, and the third pole ear 10 is closer to the winding core hole 3 than the fourth pole ear 11, wherein the third pole ear 10 is located in the third winding core layer away from the head end of the pole piece 2, and the fourth pole ear 11 is located in the fourth winding core layer close to the head end of the pole piece 2.

[0075] That is to say, there is a core layer without a tab between the third core layer and the fourth core layer. That is, in this embodiment, there is one or more core layers without a tab in the cylindrical core 1, and two core layers adjacent to this part of the core layer are provided with tabs, and a spacing is provided between adjacent tabs in the two core layers.

[0076] Meanwhile, the distance between the third pole tab 10 and the fourth pole tab 11 is L1, and L1 is between 20 mm and 280 mm. Specifically, it can be any value among 20 mm, 40 mm, 80 mm, 120 mm, 160 mm, 200 mm, 240 mm, 280 mm, etc., or a value between any two values.

[0077] In this embodiment, by providing one or more consecutive core layers without tabs in the cylindrical core 1, the tabs are easily folded in the radial direction of the core hole 3, thereby avoiding the difficulty of folding the tabs. In addition, by providing a spacing between two adjacent tabs, it is equivalent to avoiding too many layers without tabs, resulting in insufficient current capacity of the core layers without tabs.

[0078] At the same time, setting a certain distance between the pole ears on two adjacent winding core layers can help manage the current distribution to a certain extent, and can also enhance the stability and safety of the battery structure. If the distance is too small, then when the winding length of the pole piece 2 is constant, the number of pole ears will increase, making it inconvenient to fold the pole ears. If the distance is too large, then when the winding length of the pole piece 2 is constant, the number of pole ears will be reduced. Once the number of pole ears is reduced to a certain extent, it will seriously affect the overall overcurrent performance of the battery. Furthermore, a reasonable spacing between the pole ears helps with thermal management, avoids local overheating, and reduces the risk of thermal runaway. In addition, a reasonable spacing between the pole ears will not interfere with each other during the operation of welding or connecting the pole ears, thereby improving production efficiency and quality.

[0079] Furthermore, in an optional embodiment, the cylindrical core 1 includes multiple core layers, the pole ears in some core layers are not welded to the pole assembly or the shell, and the number of core layers not welded to the pole assembly or the shell is less than or equal to 15 and greater than or equal to 2.

[0080] In the embodiment of the present invention, by limiting the number of core layers that are not welded to the tabs, the stability of the internal structure of the battery and the reliability of the electrical connection can be ensured, and the overcurrent performance of the tabs can be prevented from being affected by too many unwelded layers. In addition, too many freely suspended conductors can be prevented from moving inside the battery, reducing the risk of short circuits and ensuring that the battery can still maintain good electrical contact when vibrating or deforming.

[0081] Further, in an optional embodiment, the shell further includes a liquid injection hole 12, and the positive electrode ear, the negative electrode ear and the liquid injection hole 12 are all located on the same side. The range of D1 / S is between 4 and 38. Specifically, it can be any value among 4, 10, 15, 20, 25, 30, 35, 38, etc., or a value between any two values.

[0082] In this configuration, when the tab and the injection hole 12 are at the same end, the risk of the tab blocking the winding core hole 3 is relatively high, and D1 needs to be larger, or S needs to be smaller. However, S cannot be too small, which will affect the storage of electrolyte. Therefore, D1 and S can be adjusted comprehensively to achieve the same technical effect. This embodiment does not limit this, and those skilled in the art can make changes according to actual conditions.

[0083] Further, in an optional embodiment, the ratio of the area of ​​the injection hole 12 to the area of ​​the winding core hole 3 is in the range of 0.2 to 0.8. Specifically, it can be any value among 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, etc. or a value between any two values.

[0084] In this arrangement, the pole ear and the injection hole 12 are arranged at the same end, and the pole ear is easy to block the injection hole 12 and affect the injection. The ratio between the area of ​​the injection hole 12 and the area of ​​the core hole 3 cannot be too small. If it is too small, the area of ​​the core hole 3 will be larger, so the risk of the pole ear covering the core hole 3 is greater; or the area of ​​the injection hole 12 is small, resulting in low injection efficiency, and the risk of the core hole 3 being covered is high, and the electrolyte infiltration effect of the pole piece 2 is poor. However, the ratio between the area of ​​the injection hole 12 and the area of ​​the core hole 3 cannot be too large. If the area of ​​the injection hole 12 is too large and the area of ​​the core hole 3 is small, the core hole 3 will be able to accommodate less electrolyte.

[0085] Further, in an optional embodiment, since the cylindrical core 1 includes a plurality of core layers, the core layer closest to the core hole 3 is the first core layer.

[0086] like Figure 7 As shown, after the pole piece 2 is unfolded, the distance between two adjacent pole ears in the first winding core layer and the adjacent winding core layer is D3, and the range of D3 is between 20mm and 80mm. Specifically, it can be any value among 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, etc., or a value between any two values.

[0087] Each winding layer is usually provided with a certain number of pole lugs. When the first winding layer includes only a single pole lug, namely the first pole lug 7 , D3 is the distance between the first pole lug 7 and the pole lug in the adjacent winding layer.

[0088] Likewise, if Figure 6 and Figure 7 As shown, D3 refers to the minimum distance between the first pole tab 7 and the pole tabs in the adjacent winding core layer. In addition, the pole tab can be rectangular or trapezoidal.

[0089] Of course, this embodiment is only an example to illustrate the specific shape of the pole ear, but it is not limited to this. Those skilled in the art can make changes according to actual conditions as long as the same technical effect can be achieved.

[0090] When the first winding layer includes a plurality of tabs, D3 is the distance between two adjacent tabs in the first winding layer and an adjacent winding layer.

[0091] In this configuration, in order to prevent the tab from blocking the winding core hole 3, the distance between the first tab 7 and the winding head end 6 is increased, resulting in poor current carrying capacity of the pole piece 2. Therefore, it is necessary to control the distance between the first tab 7 and the adjacent tab to avoid poor current carrying capacity.

[0092] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery, characterized in that: include: A shell and a cylindrical winding core (1), wherein the shell comprises a pole assembly, and the cylindrical winding core (1) comprises a winding core hole (3) and a pole piece (2); the pole piece (2) comprises a pole piece body and a plurality of pole ears; the pole ears are used to be electrically connected to the pole assembly and, or, the shell; The pole piece (2) comprises a winding head end (6), the pole ear comprises a first pole ear (7), in the length direction after the pole piece (2) is unfolded, the distance between the first pole ear (7) and the winding head end (6) is D1, the area of ​​the winding core hole (3) is S, and the range of D1 / S is between 3 and 45; After the pole piece (2) is unfolded, the distance between two adjacent pole ears in the first winding core layer and the adjacent winding core layer is D3; the first winding core layer is the winding core layer closest to the winding core hole (3); D3 is the minimum distance between two adjacent tabs in the first winding layer and the adjacent winding layer.

2. The battery according to claim 1, characterized in that The area of ​​the winding core hole (3) is 0.7 mm 2 Up to 80mm 2 between.

3. The battery according to claim 2, characterized in that The positive electrode ear and the negative electrode ear are arranged on the same side of the winding core hole (3) along the axial direction, and after the pole piece (2) is unfolded, D1 is between 200 mm and 900 mm; Alternatively, the positive electrode ear and the negative electrode ear are arranged on opposite sides of the winding core hole (3) along the axial direction, and after the pole piece (2) is unfolded, D1 is between 150 mm and 850 mm.

4. The battery according to any one of claims 1 to 3, characterized in that: The cylindrical winding core (1) comprises a plurality of winding core layers arranged in a radial direction, and some of the winding core layers are not provided with pole ears.

5. The battery according to claim 4, characterized in that The second winding core layer is defined as the winding core layer farthest from the winding core hole (3). Among all the winding core layers, except for the first winding core layer and the second winding core layer, some winding core layers in the middle position are not provided with pole ears.

6. The battery according to claim 4, characterized in that There is a winding core layer without a pole ear, and in the two third and fourth winding core layers adjacent to the winding core layer without a pole ear, both of which are provided with pole ears, the third pole ear (10) is arranged on the third winding core layer, and the fourth pole ear (11) is arranged on the fourth winding core layer, and the third pole ear (10) is closer to the winding core hole (3) than the fourth pole ear (11), wherein the third pole ear (10) is located in the third winding core layer away from the front end of the pole piece (2); and the fourth pole ear (11) is located in the fourth winding core layer close to the front end of the pole piece (2).

7. The battery according to claim 6, characterized in that The distance between the third pole tab (10) and the fourth pole tab (11) is L1, and L1 is between 20 mm and 280 mm.

8. The battery according to any one of claims 1 to 3, characterized in that: The cylindrical winding core (1) comprises a plurality of winding core layers, the pole ears in some winding core layers are not welded to the pole assembly or the shell, and the number of winding core layers not welded to the pole assembly or the shell is less than or equal to 15 and greater than or equal to 2.

9. The battery according to any one of claims 1 to 3, characterized in that: The D3 range is between 20mm and 80mm.

10. The battery according to claim 9, characterized in that When the first winding core layer only includes the first pole lug (7), D3 is the distance between the first pole lug (7) and the pole lug in the adjacent winding core layer; When the first winding layer includes a plurality of tabs, D3 is the distance between two adjacent tabs in the first winding layer and an adjacent winding layer.

Images