Roll core, battery cell and battery

Abstract

The utility model provides a roll core, a battery cell and a battery, and relates to the technical field of batteries. The roll core comprises a roll core main body and a first tab; the roll core main body comprises a first pole piece, a diaphragm and a second pole piece, and the roll core main body is provided with a first end part along the axial direction of the roll core; the first tab is arranged at the first end part and is connected to the first pole piece; the plurality of layers of first tabs are stacked at the first end part to form a first tab region extending in the circumferential direction, and at least one first inner tab-free region and at least one first outer tab-free region are respectively arranged on the inner circumferential side and the outer circumferential side of the first tab region; the first inner tab-free area and the first outer tab-free area are arranged in a staggered manner along the circumferential direction of the roll core main body. In the application, the first inner tab-free area and the first outer tab-free area are respectively arranged on the inner peripheral side and the outer peripheral side of the first tab area, so that the electrolyte can directly flow into the roll core through the tab-free area of the first end part, the path of the electrolyte to infiltrate the roll core can be shortened, and the infiltration efficiency of the roll core can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a winding core, a battery cell and a battery. Background Art

[0002] In related technologies, a battery includes a casing and a winding core disposed within the casing. The winding core comprises a positive electrode sheet, a negative electrode sheet, and a separator, stacked and wound in sequence. The electrode sheet comprises a coated area and a hollow foil area surrounding the coated area. The coated area is used to apply the active material, while the hollow foil area serves as the tab.

[0003] In order to control the height of the tabs inside the battery cell, the tabs need to be flattened, that is, the tabs are bent toward the end face of the core so that adjacent tabs are stacked along the axial direction of the core to form a tab area. However, the flattened tabs will block the end of the core, causing the electrolyte to mainly flow down from the middle hole of the core to the bottom of the inner cavity of the battery cell, and then the electrolyte is adsorbed by the electrode to the top of the core to complete the infiltration of the core. In this way, the path for the electrolyte to infiltrate the core is longer, resulting in poor infiltration efficiency of the core. Utility Model Content

[0004] The embodiments of the present application provide a winding core, a battery cell, and a battery, which can improve the wetting efficiency of the winding core.

[0005] In the first aspect, an embodiment of the present application provides a winding core, which includes a winding core body and a first pole piece; the winding core body includes a first pole piece, a diaphragm and a second pole piece that are wound together, the diaphragm is located between the first pole piece and the second pole piece, the polarity of the first pole piece and the second pole piece are opposite, and the winding core body has a first end along the axial direction of the winding core; multiple layers of first pole pieces are arranged at the first end and connected to the first pole piece; wherein the multiple layers of first pole pieces are stacked on the first end to form a first pole piece area, the first pole piece area extends along the circumference of the winding core body, and at least one first inner pole piece-free area is provided on the inner circumference side of the first pole piece area, and at least one first outer pole piece-free area is provided on the outer circumference side of the first pole piece area; along the circumference of the winding core body, the first inner pole piece-free area and the first outer pole piece-free area are staggered.

[0006] In one embodiment, with the axial direction of the winding core as the projection direction, the projection area of the first tab region is S1, and the area of the first end portion is S, satisfying: 0.5≤S1 / S<1.

[0007] In one embodiment, with the axial direction of the winding core as the projection direction, the projection of the first inner tab-free region is a fan-shaped ring, with the small end of the fan-shaped ring facing the axis of the winding core.

[0008] In one embodiment, the central angle of the first inner tab-free region is α1, which satisfies: 10°≤α1≤45°.

[0009] In one embodiment, with the axial direction of the winding core as the projection direction, the projection of the first outer tab-free region is a fan-shaped ring, with the small end of the fan-shaped ring facing the axis of the winding core.

[0010] In one embodiment, the central angle of the first outer tab-free region is α2, which satisfies: 10°≤α2≤45°.

[0011] In one embodiment, at least one first inner lug-free region corresponds one-to-one to at least one first outer lug-free region. Along the circumference of the core body, the first outer lug-free region has an offset angle δ1 relative to the corresponding first inner lug-free region. The central angle of the first inner lug-free region is α1, the central angle of the first outer lug-free region is α2, and the number of first inner lug-free regions is n, satisfying: α1≤δ1≤360° / n-α2.

[0012] In one embodiment, the winding core further includes a second pole tab, the winding core having a second end portion disposed opposite to the first end portion; the second pole tab is disposed at the second end portion and connected to the second pole piece; wherein multiple layers of the second pole tab are stacked on the second end portion to form a second pole tab region, the second pole tab region extending along the circumference of the winding core body, at least one second inner pole tab-free region is disposed on the inner circumference of the second pole tab region, and at least one second outer pole tab-free region is disposed on the outer circumference of the second pole tab region;

[0013] At least one second inner tab-free region corresponds one-to-one to at least one first inner tab-free region, and along the axial direction of the roll core, the second inner tab-free region overlaps with the corresponding first inner tab-free region at most partially, and along the circumferential direction of the roll core body, the second inner tab-free region has a deviation angle β1 relative to the corresponding first inner tab-free region, satisfying: 5°≤β1≤45°, and / or, at least one second outer tab-free region corresponds one-to-one to at least one first outer tab-free region, and the second outer tab-free region overlaps with the corresponding first outer tab-free region at most partially, and along the circumferential direction of the roll core body, the second outer tab-free region has a deviation angle β2 relative to the corresponding first outer tab-free region, satisfying: 5°≤β2≤45°.

[0014] In a second aspect, an embodiment of the present application provides a battery cell comprising a shell, a cover plate, and the aforementioned winding core; the cover plate is covered with the shell to define a accommodating cavity; and the winding core is disposed in the accommodating cavity.

[0015] In a third aspect, an embodiment of the present application provides a battery comprising the aforementioned battery cell.

[0016] Beneficial effects of the embodiments of the present application:

[0017] In an embodiment of the present application, by respectively arranging a plurality of first inner non-pole lug areas and a plurality of first outer non-pole lug areas on the inner and outer sides of the first pole lug area, the electrolyte can flow directly into the interior of the core through the first inner non-pole lug areas and the first outer non-pole lug areas, thereby shortening the path of the electrolyte infiltrating the core and further improving the infiltration efficiency of the core. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 Schematic diagram of the structure of the winding core provided in an embodiment of the present application;

[0020] Figure 2 is a structural schematic diagram of the first end portion provided in an embodiment of the present application;

[0021] Figure 3 Schematic diagram of the deflection of the first outer tab-free region relative to the corresponding first inner tab-free region provided in an embodiment of the present application;

[0022] Figure 4 Schematic diagram of another first outer tab-free region deflected relative to the corresponding first inner tab-free region provided by an embodiment of the present application;

[0023] Figure 5 is a structural schematic diagram of the second end provided in an embodiment of the present application;

[0024] Figure 6 Schematic diagram of the deflection of the second inner tab-free region relative to the corresponding first inner tab-free region provided in an embodiment of the present application;

[0025] Figure 7 is a schematic structural diagram of a battery cell provided in an embodiment of the present application;

[0026] Figure 8 It is a schematic structural diagram of a battery provided in an embodiment of the present application.

[0027] Description of reference numerals:

[0028] 001- core;

[0029] 011 - winding core body; 111 - first end; 1111 - first inner tab-free region; 1112 - first outer tab-free region; 112 - second end; 1121 - second inner tab-free region; 1122 - second outer tab-free region; 113 - middle hole;

[0030] 012-first tab area; 121-first tab;

[0031] 013-second pole lug area; 131-second pole lug;

[0032] 002-battery cell; 021-housing; 022-cover;

[0033] 003-battery; 031-box. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0035] Furthermore, it should be understood that the specific embodiments described herein are intended only to illustrate and explain the present application and are not intended to limit the present application. In this application, unless otherwise indicated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the directions of the drawings in the accompanying drawings; whereas "inner" and "outer" refer to the outline of the device.

[0036] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0037] In the description of the embodiments of this application, words such as "example" or "for example" are used to indicate an example, illustration, or description. Any embodiment or design described as "for example" or "for example" in the embodiments of this application is not to be construed as being preferred or having more advantages than another embodiment or design. The use of words such as "example" or "for example" is intended to clearly present relative concepts.

[0038] To facilitate understanding of the solution of the present application, the spline curves and arrows used in the drawings are explained here: the components indicated by the spline curves without arrows are solid components, that is, components with solid structures; the components indicated by the spline curves with arrows are virtual components, that is, components without solid structures.

[0039] See also Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of the winding core 001 provided in an embodiment of the present application. Figure 2 Schematic diagram of the structure of the first end 111 provided in an embodiment of the present application. An embodiment of the present application provides a winding core 001, comprising a winding core body 011 and a first pole piece 121. The winding core body 011 comprises a first pole piece, a diaphragm, and a second pole piece wound together. The diaphragm is located between the first pole piece and the second pole piece. The first pole piece and the second pole piece have opposite polarities. Along the axial direction of the winding core 001, the winding core body 011 has a first end 111. Multiple layers of first pole pieces 121 are disposed at the first end 111 and connected to the first pole piece. The multiple layers of first pole pieces 121 are stacked on the first end 111 to form a first pole piece region 012. The first pole piece region 012 extends circumferentially along the winding core body 011. At least one first inner pole piece-free region 1111 is disposed on the inner circumference of the first pole piece region 012. At least one first outer pole piece-free region 1112 is disposed on the outer circumference of the first pole piece region 012. Along the circumference of the core body 011 , the first inner tab-free region 1111 and the first outer tab-free region 1112 are alternately arranged.

[0040] Specifically, the number of the first inner non-polar lug area 1111 and the first outer non-polar lug area 1112 can be one or more, for example, three or five. When there are multiple first inner non-polar lug areas 1111 and the first outer non-polar lug areas 1112, the multiple first inner non-polar lug areas 1111 and the multiple first outer non-polar lug areas 1112 are respectively arranged at intervals along the circumference of the core body 011. In this embodiment, the number of the first inner non-polar lug area 1111 and the first outer non-polar lug area 1112 are both three, such as Figure 1 shown.

[0041] Furthermore, the first tab region 012 may extend in a ring shape or a sector ring shape along the circumference of the core body 011. The sector ring shape may be one or more. If there are multiple sector ring shapes, the multiple sector ring shapes are spaced apart along the circumference of the core body 011. The sector ring shape refers to a shape formed by the first tab region 012 extending along the circumference of the core body 011, with the central angle of the extension being less than 360°.

[0042] It is understood that the inner diameter and outer diameter refer to the diameters of the relevant parts. The tab-free area is the area on the end surface of the core 001 where no tabs are provided. Before being bent, the tabs are parallel to the axial direction of the core 001. After being bent, the tabs are stacked in sequence along the axial direction of the core 001 to form the tab area.

[0043] The first electrode sheet includes a coated area coated with an active material and an uncoated area uncoated with the active material. The first electrode tab 121 may be integrally provided as at least a portion of the uncoated area. In other embodiments, the first electrode tab 121 may be separately welded to the first electrode sheet.

[0044] In addition, the first electrode tab 121 can be a positive electrode tab or a negative electrode tab.

[0045] In this embodiment, by respectively arranging the first inner non-polar lug area 1111 and the first outer non-polar lug area 1112 on the inner and outer sides of the first polar lug area 012, on the one hand, the electrolyte can flow directly into the interior of the core 001 through the top of the core 001, thereby shortening the path of the electrolyte infiltrating the core 001, and further improving the infiltration efficiency of the core 001; on the other hand, the core 001 can have multiple liquid inlet parts on the first end 111, and the multiple liquid inlet parts respectively infiltrate inward along the outer circumference of the core 001 and infiltrate inward along the inner circumference of the core 001, which can improve the uniformity of the infiltration of the core 001, thereby further improving the infiltration efficiency of the core 001.

[0046] In addition, by staggering multiple first inner tab-free areas 1111 and multiple first outer tab-free areas 1112 in sequence, the first inner tab-free areas 1111 and the first outer tab-free areas 1112 can be at least partially non-opposite to each other, thereby ensuring that the first tab area 012 between the first inner tab-free areas 1111 and the first outer tab-free areas 1112 has a larger area, thereby ensuring the ease of operation and reliability of welding the first tab area 012 located between the first inner tab-free areas 1111 and the first outer tab-free areas 1112 to the collecting plate.

[0047] In one embodiment, with the axial direction of the winding core 001 as the projection direction, the projection area of the first tab region 012 is S1, and the area of the first end portion 111 is S, which satisfies: 0.5≤S1 / S<1.

[0048] It can be understood that the plane perpendicular to the axis of the winding core 001 is the projection plane, and in the projection plane, the projection area of the first tab region 012 is S1.

[0049] Illustratively, the ratio between the area S1 of the first tab region 012 in the projection plane and the area S of the first end portion 111 includes but is not limited to: 0.5, 0.52, 0.55, 0.58, 0.6, 0.62, 0.63, 0.64, 0.66, 0.66, 0.68, 0.7, 0.72, 0.76, 0.78, 0.8, 0.85, 0.9, and 0.95.

[0050] Further, 0.5≤S1 / S≤0.8.

[0051] In this embodiment, through the above-mentioned limitation, on the one hand, the first tab region 012 can have a sufficient area to meet the current collection requirements of the core 001; on the other hand, it can avoid the first tab region 012 being too large and causing the area of the tab-free region to be too small, thereby ensuring the liquid inlet speed of the first end portion 111, which is beneficial to improving the wetting efficiency of the core 001.

[0052] See also Figure 2 In one embodiment, with the axial direction of the winding core 001 as the projection direction, the projection of the first inner tab-free area 1111 is a fan ring, and the small end of each fan ring faces the axis of the winding core 001.

[0053] It can be understood that, taking the plane perpendicular to the axis of the winding core 001 as the projection plane, in this projection plane, the projection of the first inner tab-free area 1111 is a fan-shaped ring.

[0054] The fan-shaped ring refers to a shape formed by the first inner tab-free area 1111 extending along the circumference of the core body 011, with the central angle of the extension being less than 360°.

[0055] In this embodiment, through the above-mentioned setting, the size of the first inner lug-free area 1111 in the circumferential direction of the winding core 001 can be positively correlated with the circumferential size of the first lug area 012, thereby increasing the area of the first inner lug-free area 1111, which is conducive to improving the wetting efficiency, and reducing the influence of the first inner lug-free area 1111 on the circumferential size of the first lug area 012, which is conducive to improving the operability and reliability of welding the first lug area 012 to the collecting plate.

[0056] See also Figure 2 In one embodiment, the central angle of the first inner tab-free region 1111 is α1, which satisfies the following relationship: 10°≤α1≤45°.

[0057] It will be understood that α1 includes but is not limited to 10°, 12°, 14.5°, 16°, 17°, 18°, 19°, 20°, 22°, 26°, 29°, 30°, 36°, 38°, 39°, 40°, 42.5°, 44°, and 45°.

[0058] Furthermore, 20°≤α1≤35°.

[0059] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the size of the first inner lug-free area 1111 in the circumferential direction of the winding core 001 being too small, which is not conducive to the flow of the electrolyte. On the other hand, it is possible to avoid the size of the first inner lug-free area 1111 in the circumferential direction of the winding core 001 being too large, which causes the area of the first lug area 012 at the circumference of the first inner lug-free area 1111 to be too small, thereby ensuring that the first lug area 012 at the circumference of the first inner lug-free area 1111 has a larger area, thereby ensuring the ease of operation and reliability of welding the first lug area 012 located on the circumference to the collecting plate.

[0060] See also Figure 2 In one embodiment, with the axial direction of the winding core 001 as the projection direction, the projection of the first outer tab-free region 1112 is a fan ring, and the small end of each fan ring faces the axis of the winding core 001.

[0061] It can be understood that, taking the plane perpendicular to the axis of the winding core 001 as the projection plane, in this projection plane, the projection of the first outer tab-free region 1112 is a fan ring.

[0062] In this embodiment, through the above-mentioned setting, the size of the first outer lug-free area 1112 in the circumferential direction of the winding core 001 can be positively correlated with the circumferential size of the first lug area 012, thereby increasing the area of the second outer lug-free area 1122 to improve the wetting efficiency, and reducing the influence of the first outer lug-free area 1112 on the circumferential size of the first lug area 012, so as to improve the operability and reliability of welding the first lug area 012 to the collecting plate.

[0063] See also Figure 2 In one embodiment, the central angle of the first outer tab-free region 1112 is α2, satisfying: 10°≤α2≤45°.

[0064] It will be understood that α2 includes but is not limited to 10°, 12°, 14.5°, 16°, 17°, 18°, 19°, 20°, 22°, 26°, 29°, 30°, 36°, 38°, 39°, 40°, 42.5°, 44°, and 45°.

[0065] Furthermore, 20°≤α2≤35°.

[0066] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the size of the first outer lug-free area 1112 in the circumferential direction of the winding core 001 being too small, which is not conducive to the flow of the electrolyte. On the other hand, it is possible to avoid the size of the first outer lug-free area 1112 in the circumferential direction of the winding core 001 being too large, which causes the area of the first lug area 012 at the circumference of the first inner and outer lug areas to be too small, thereby ensuring that the first lug area 012 at the circumference of the first outer lug-free area 1112 has a larger area, thereby ensuring the ease of operation and reliability of welding the first lug area 012 located on the circumference to the collecting plate.

[0067] See also Figure 2 In one embodiment, at least one first inner tab-free region 1111 corresponds one-to-one to at least one first outer tab-free region 1112. Along the circumference of the core body 011, the first outer tab-free region 1112 has a deviation angle δ1 relative to the corresponding first inner tab-free region 1111. The central angle of the first inner tab-free region 1111 is α1, the central angle of the first outer tab-free region 1112 is α2, and the number of the first inner tab-free regions 1111 is n, satisfying: α1≤δ1≤360° / n-α2.

[0068] It can be understood that when there are multiple first inner tab-free regions 1111 and first outer tab-free regions 1112, there can be a one-to-one correspondence between one first inner tab-free region 1111 and one first outer tab-free region 1112, or there can be a one-to-one correspondence between X first inner tab-free regions 1111 and X first outer tab-free regions 1112, where X is a natural number and X≤n.

[0069] For example, when n is 2, α1≤δ1≤180°-α2, such as Figure 3 As shown, Figure 3 This is a schematic diagram of the deflection of the first outer non-polar lug region 1112 relative to the corresponding first inner non-polar lug region 1111 provided in an embodiment of the present application. The dotted line in the figure is the maximum position to which the first outer non-polar lug region 1112 can be deflected relative to the corresponding first inner non-polar lug region 1111 as shown by the thick line.

[0070] When n is 3, α1≤δ1≤120°-α2, such as Figure 4 As shown, Figure 4 This is another schematic diagram of the deflection of the first outer non-polar lug region 1112 relative to the corresponding first inner non-polar lug region 1111 provided in an embodiment of the present application. The dotted line in the figure is the maximum position to which the first outer non-polar lug region 1112 can be deflected relative to the corresponding first inner non-polar lug region 1111 as shown by the thick line.

[0071] Specifically, 2≤n≤6.

[0072] In this embodiment, through the above-mentioned limitations, the first outer tab-free area 1112 and the first inner tab-free area 1111 can be completely staggered, thereby increasing the area of the first tab-free area 012 between the first inner tab-free area 1111 and the first outer tab-free area 1112, and further improving the operability and reliability of welding the first tab-free area 012 between the first inner tab-free area 1111 and the first outer tab-free area 1112 to the collecting plate.

[0073] See also Figure 2 In one embodiment, the outer diameter of the first tab region 012 is smaller than the outer diameter of the core body 011 . Specifically, the outer diameter of the first tab region 012 is B, and the outer diameter of the core body 011 is A, satisfying 0.8A≤B<A.

[0074] It can be understood that B includes but is not limited to: 0.8A, 0.81A, 0.81.5A, 0.82A, 0.83A, 0.84A, 0.85A, 0.86A, 0.88A, 0.9A, 0.92A, 0.95A, and 0.99A.

[0075] For example,

[0076] When A is 44.6mm, 35.68mm≤B<44.6mm;

[0077] When A is 45mm, 36mm≤B<45mm;

[0078] When A is 45.2mm, 36.16mm≤B<45.2mm.

[0079] Furthermore, 0.8A≤B≤0.95A.

[0080] In this embodiment, through the above-mentioned limitation, on the one hand, a gap can be formed between the outer periphery of the first pole lug area 012 and the outer periphery of the core body 011, so that the electrolyte can infiltrate the core 001 through the gap, and it can be beneficial for the core 001 to enter the shell, thereby improving the assembly convenience of the core 001; on the other hand, it can avoid the outer diameter of the first pole lug area 012 being too small, resulting in a smaller area of the first pole lug 121, thereby ensuring the area of the first pole lug 121, so that the current collecting capacity of the first pole piece meets the requirements.

[0081] See also Figure 2 In one embodiment, the inner diameter of the first tab region 012 is C, and the outer diameter of the winding core body 011 is A, satisfying: 0.02A≤C≤0.25A.

[0082] It can be understood that C includes but is not limited to: 0.02A, 0.06A, 0.08A, 0.1A, 0.11A, 0.12A, 0.15A, 0.18A, 0.2A, 0.4A, and 0.25A.

[0083] For example,

[0084] When A is 44.6 mm, 0.892 mm ≤ C ≤ 11.5 mm;

[0085] When A is 45mm, 0.9mm≤C≤11.25mm;

[0086] When A is 45.2mm, 0.904mm≤C≤11.3mm.

[0087] Furthermore, 0.1A≤C≤0.25A.

[0088] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the first pole lug 121 blocking the middle hole 113 of the winding core 001, so that a space for the electrolyte to flow can be formed on the inner peripheral side of the first pole lug area 012 to ensure the smooth flow of the electrode liquid; on the other hand, it is possible to avoid the inner diameter of the first pole lug area 012 being too large, resulting in a smaller area of the first pole lug 121, so that the area of the first pole lug 121 can be guaranteed, so that the current collecting capacity of the first pole piece meets the requirements.

[0089] See also Figure 5 , Figure 5 : is a structural schematic diagram of the second end portion 112 provided in an embodiment of the present application. The winding core 001 also includes a second pole lug 131. The winding core 001 has a second end portion 112 disposed opposite to the first end portion 111; the second pole lug 131 is disposed at the second end portion 112 and is connected to the second pole piece; wherein multiple layers of second pole lugs 131 are stacked on the second end portion 112 to form a second pole lug region 013. The second pole lug region 013 extends along the circumference of the winding core body 011. At least one second inner pole lug-free region 1121 is disposed on the inner circumference of the second pole lug region 013, and at least one second outer pole lug-free region 1122 is disposed on the outer circumference of the second pole lug region 013.

[0090] The second tab region 013 may extend in a ring shape or a sector ring shape along the circumference of the core body 011. The sector ring shape may be one or multiple. If multiple sector ring shapes are provided, the multiple sector ring shapes are spaced apart along the circumference of the core body 011. A sector ring shape refers to a shape formed by the second tab region 013 extending along the circumference of the core body 011, with the central angle of the extension being less than 360°.

[0091] Specifically, the second electrode sheet includes a coated area coated with an active material and an uncoated area uncoated with the active material. The second electrode tab 131 can be integrally provided as at least a portion of the uncoated area. In other embodiments, the second electrode tab 131 can be separately welded to the second electrode sheet.

[0092] In addition, one of the first tab 121 and the second tab 131 is a positive tab and the other is a negative tab. Typically, the tab closest to the top cover of the battery cell is the positive tab.

[0093] In this embodiment, through the above-mentioned arrangement, the second end portion 112 can have multiple channels inside the battery cell for electrolyte infiltration, thereby improving the infiltration efficiency of the core 001; on the other hand, the core 001 can have multiple liquid inlet portions on the second end portion 112, and the multiple liquid inlets are distributed to infiltrate inward along the outer circumference of the core 001 and inward along the inner circumference of the core 001, respectively, which can improve the uniformity of the infiltration of the core 001, thereby further improving the infiltration efficiency of the core 001.

[0094] Among them, the structure and layout of the second tab area 013, the second inner tab-free area and the second outer tab-free area 1122 on the second end 112 are respectively consistent with the structure and layout of the first tab area 012, the first inner tab-free area and the first outer tab-free area 1112 on the first end 111. The details are as follows:

[0095] Along the circumference of the core body 011 , a plurality of second inner tab-free areas and a plurality of second outer tab-free areas 1122 are alternately arranged.

[0096] Furthermore, with the axial direction of the winding core 001 as the projection direction and the plane where the second end 112 is located as the projection plane, the area of the second tab region 013 in the projection plane is S2, and the area of the second end 112 is S, satisfying: 0.5≤S2 / S<1. Furthermore, 0.5≤S2 / S≤0.8.

[0097] Furthermore, taking the axial direction of the core 001 as the projection direction and the plane where the first end 111 is located as the projection plane, the projection of the first inner lug-free area 1111 in the projection plane is a fan-shaped ring, with the small end of the fan-shaped ring facing the axis of the core 001, and the projection of the first outer lug-free area 1112 in the projection plane is a fan-shaped ring, with the small end of the fan-shaped ring facing the axis of the core 001.

[0098] Specifically, the central angle of the second inner tab-free region 1121 is α3, which satisfies: 10°≤α3≤45°. Further, 20°≤α3≤35°.

[0099] The central angle of the second outer tab-free region 1122 is α4, which satisfies: 10°≤α4≤45°. Furthermore, 20°≤α4≤35°.

[0100] Among them, at least one second inner tab-free area 1121 corresponds one-to-one to at least one second outer tab-free area 1122. Along the circumference of the core body 011, the second outer tab-free area 1122 has a deviation angle δ2 relative to the corresponding second inner tab-free area 1121. The central angle of the second inner tab-free area 1121 is α3, the central angle of the second outer tab-free area 1122 is α4, and the number of second inner tab-free areas 1121 is n, satisfying: α3≤δ2≤360° / n-α4.

[0101] It can be understood that when there are multiple second inner tab-free areas 1121 and second outer tab-free areas 1122, there can be a one-to-one correspondence between one second inner tab-free area 1121 and one second outer tab-free area 1122, or there can be a one-to-one correspondence between Z second inner tab-free areas 1121 and Z second outer tab-free areas 1122, where Z is a natural number and Z≤n.

[0102] See also Figure 6 , Figure 6 Schematic diagram of the deflection of the first inner tab-free region 1111 relative to the corresponding second inner tab-free region 1121 provided in an embodiment of the present application. Figure 6 , the dotted line shows the first inner tab-free area and the first outer tab-free area 1112, and the solid line shows the second end 112. In one embodiment, at least one second inner tab-free area 1121 corresponds to at least one first inner tab-free area 1111 one-to-one, and along the axial direction of the winding core 001, the second inner tab-free area 1121 overlaps with the corresponding first inner tab-free area 1111 at most partially, and / or, at least one second outer tab-free area 1122 corresponds to at least one first outer tab-free area 1112 one-to-one, and the second outer tab-free area 1122 overlaps with the corresponding first outer tab-free area 1112 at most partially.

[0103] It can be understood that when there are multiple second inner non-protagon lug areas 1121 and first inner non-protagon lug areas 1111, at least one second inner non-protagon lug area 1121 corresponds to at least one first inner non-protagon lug area 1111, specifically: Y second inner non-protagon lug areas 1121 correspond to Y first inner non-protagon lug areas 1111, wherein Y is a natural number, and Y is an integer not greater than the number of second inner non-protagon lug areas 1121. Similarly, when there are multiple second outer non-protagon lug areas 1122 and first outer non-protagon lug areas 1112, at least one second outer non-protagon lug area 1122 corresponds to at least one first outer non-protagon lug area 1112, specifically: M second outer non-protagon lug areas 1122 correspond to M first outer non-protagon lug areas 1112, wherein M is a natural number, and M is an integer not greater than the number of second outer non-protagon lug areas 1122.

[0104] In addition, the second inner tab-free region 1121 overlaps with the corresponding first inner tab-free region 1111 at most partially, that is, the second inner tab-free region 1121 has a bias angle relative to the corresponding first inner tab-free region 1111; the second outer tab-free region 1122 overlaps with the corresponding first outer tab-free region 1112 at most partially, that is, the second outer tab-free region 1122 has a bias angle relative to the corresponding first outer tab-free region 1112.

[0105] Specifically, along the circumference of the core body 011, the second inner tab-free zone 1121 has a deviation angle β1 relative to the corresponding first inner tab-free zone 1111, satisfying: 5°≤β1≤45°, and / or, along the circumference of the core body 011, the second outer tab-free zone 1122 has a deviation angle β2 relative to the corresponding first outer tab-free zone 1112, satisfying: 5°≤β2≤45°.

[0106] It will be understood that β1 and β2 include but are not limited to 5°, 8°, 10°, 12.5°, 15°, 18°, 19°, 20°, 21.2°, 24°, 25°, 27°, 29°, 35°, 38°, 40°, 42°, and 45°.

[0107] In this embodiment, through the above-mentioned arrangement, the tab-free area of the second end 112 is deflected relative to the tab-free area of the first end 111. On the one hand, the first end 111 and the second end 112 can respectively enter the liquid from different radial positions of the core 001, thereby further improving the uniformity of the wetting of the core 001, and thus improving the efficiency of the wetting of the core 001; on the other hand, the first inner tab-free area 1111 and the second inner tab-free area 1121 can be at least partially arranged opposite to the second tab area 013, so that when the electrode liquid flowing into the core 001 from the first inner tab-free area 1111 and the second inner tab-free area 1121 is discharged from the second end 112, the discharge of this part of the electrolyte is slowed down due to the obstruction of the second tab area 013, so that more electrolyte can be retained in the core 001, thereby improving the electrolyte wetting efficiency.

[0108] See also Figure 7 , Figure 7 Schematic diagram of the structure of a battery cell 002 provided in an embodiment of the present application. Accordingly, an embodiment of the present application provides a battery cell 002 comprising a housing 021, a cover plate 022, and the aforementioned winding core 001; the cover plate 022 and the housing 021 are combined to define a receiving cavity; the winding core 001 is disposed within the receiving cavity.

[0109] In this embodiment, by adopting the aforementioned winding core 001, on the one hand, the electrolyte can flow directly into the interior of the winding core 001 through the top of the winding core 001, thereby shortening the path of the electrolyte infiltrating the winding core 001, and further improving the infiltration efficiency of the battery cell 002; on the other hand, the winding core 001 can have multiple liquid inlet parts on the first end 111, and the multiple liquid inlet parts respectively infiltrate inward along the outer circumference of the winding core 001 and infiltrate inward along the inner circumference of the winding core 001, which can improve the uniformity of the infiltration of the winding core 001, thereby further improving the infiltration efficiency of the battery cell 002.

[0110] See also Figure 8 , Figure 8 003 is a schematic diagram of the structure of a battery 003 provided in an embodiment of the present application. The embodiment of the present application provides a battery 003, and the battery 003 includes the aforementioned battery cell 002.

[0111] It can be understood that the battery 003 may also include a box or a base plate, and the battery cell 002 is arranged in the box, or the battery cell 002 is installed on the base plate.

[0112] In this embodiment, by adopting the aforementioned battery cell 002, on the one hand, the electrolyte can flow directly into the interior of the core 001 through the top of the core 001, thereby shortening the path of the electrolyte infiltrating the core 001, thereby improving the manufacturing efficiency of the battery 003; on the other hand, the core 001 can have multiple liquid inlet parts on the first end 111, and the multiple liquid inlet parts respectively infiltrate inward along the outer circumference of the core 001 and infiltrate inward along the inner circumference of the core 001, which can improve the uniformity of the infiltration of the core 001, thereby further improving the manufacturing efficiency of the battery 003.

[0113] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A winding core, characterized in that: include: A winding core body, comprising a first pole piece, a diaphragm, and a second pole piece wound together, wherein the diaphragm is located between the first pole piece and the second pole piece, the first pole piece and the second pole piece having opposite polarities, and the winding core body having a first end along the axial direction of the winding core; a first pole lug, disposed at the first end portion and connected to the first pole piece; Among them, multiple layers of the first pole tabs are stacked on the first end to form a first pole tab area, the first pole tab area extends along the circumference of the core body, at least one first inner pole tab-free area is arranged on the inner circumference side of the first pole tab area, and at least one first outer pole tab-free area is arranged on the outer circumference side of the first pole tab area; along the circumference of the core body, the first inner pole tab-free area and the first outer pole tab-free area are staggered.

2. The winding core according to claim 1, characterized in that Taking the axial direction of the winding core as the projection direction, the projection area of the first tab region is S1, and the area of the first end portion is S, satisfying: 0.5≤S1 / S<1.

3. The winding core according to claim 1, characterized in that Taking the axial direction of the winding core as the projection direction, the projection of the first inner tab-free area is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the winding core.

4. The winding core according to claim 3, characterized in that The central angle of the first inner tab-free region is α1, which satisfies the following conditions: 10°≤α1≤45°.

5. The winding core according to claim 1, characterized in that Taking the axial direction of the winding core as the projection direction, the projection of the first outer tab-free area is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the winding core.

6. The winding core according to claim 5, characterized in that The central angle of the first outer tab-free region is α2, which satisfies the following conditions: 10°≤α2≤45°.

7. The winding core according to any one of claims 1 to 6, characterized in that: At least one of the first inner tab-free regions corresponds one-to-one to at least one of the first outer tab-free regions. Along the circumference of the core body, the first outer tab-free region has an offset angle δ1 relative to the corresponding first inner tab-free region. The central angle of the first inner tab-free region is α1, the central angle of the first outer tab-free region is α2, and the number of the first inner tab-free regions is n, satisfying: α1≤δ1≤360° / n-α2.

8. The winding core according to any one of claims 1 to 6, characterized in that: The winding core further includes a second pole tab, the winding core having a second end portion disposed opposite to the first end portion; the second pole tab is disposed at the second end portion and connected to the second pole piece; wherein, a plurality of the second tabs are stacked on the second end portion to form a second tab region, the second tab region extending along the circumference of the winding core body, at least one second inner tab-free region being provided on the inner circumference of the second tab region, and at least one second outer tab-free region being provided on the outer circumference of the second tab region; At least one of the second inner tab-free areas corresponds one-to-one to at least one of the first inner tab-free areas. Along the axial direction of the roll core, the second inner tab-free area overlaps with the corresponding first inner tab-free area at most partially. Along the circumferential direction of the roll core body, the second inner tab-free area has an angle β1 relative to the corresponding first inner tab-free area, satisfying: 5°≤β1≤45°; and / or, at least one of the second outer tab-free areas corresponds one-to-one to at least one of the first outer tab-free areas. The second outer tab-free area overlaps with the corresponding first outer tab-free area at most partially. Along the circumferential direction of the roll core body, the second outer tab-free area has an angle β2 relative to the corresponding first outer tab-free area, satisfying: 5°≤β2≤45°.

9. A battery cell, characterized in that: include: case; a cover plate, covering the shell to define a receiving cavity; And, the winding core according to any one of claims 1 to 8 is arranged in the accommodating cavity.

10. A battery, characterized in that: Comprising the battery cell as claimed in claim 9.

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