Roll core, battery cell, battery pack and electric equipment

Abstract

The utility model provides a roll core, a battery cell, a battery pack and electric equipment, and relates to the technical field of batteries. The roll core comprises a roll core main body, a first tab, a second tab and a third tab, the roll core main body comprises a first pole piece, a second pole piece and a diaphragm arranged between the first pole piece and the second pole piece, the polarities of the first pole piece and the second pole piece are opposite, and the roll core main body is provided with a first end and a second end along the axial direction of the roll core; the first tab is arranged at the first end and is connected to the first pole piece; the second tab is arranged at the first end and is connected to the second pole piece; and the third tab is arranged at the second end, and the third tab is connected to the first pole piece or the second pole piece. In the application, the first tab and the second tab are arranged at one end of the roll core, and the third tab is arranged at the other end of the roll core, so that the current collection area of the pole piece connected with the third tab can be increased, the conduction paths of electrons are increased, and the current collection capability of the pole piece can be improved. Therefore, the current collecting capacity of the roll core can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and specifically to winding cores, battery cells, battery packs and electrical equipment. Background Art

[0002] In the related art, the battery cell includes a shell and a winding core arranged in the shell. The winding core includes a positive electrode sheet, a diaphragm and a negative electrode sheet that are stacked and wound in sequence. Usually, the positive and negative electrodes of the battery cell can be output on the same side, or they can be output from both ends of the battery cell respectively. In the structure in which the positive and negative electrodes are output on the same side, the shell of the battery cell is generally used as the output electrode of the negative electrode. At the same time, the installation position for installing the pole is insulated and isolated on the top cover sheet of the shell by a seal, and the pole is set in the installation position as the output electrode of the positive electrode. A positive electrode ear and a negative electrode ear are respectively provided at one end of the winding core close to the top cover sheet. The negative electrode ear is connected to the top cover sheet, and the positive electrode ear is connected to the pole, so that the positive and negative electrodes of the battery cell are respectively led out from the same end of the battery cell. In the structure where the positive and negative electrodes are output from both ends of the battery cell, the positive electrode ear and the negative electrode ear are respectively located at the two ends of the winding core, the positive electrode ear is connected to the positive electrode column, and the negative electrode ear is connected to the negative electrode column or the outer shell of the battery cell, thereby leading the positive and negative electrodes of the battery cell out from the two ends of the battery cell.

[0003] In the above solution, although the current collecting capacity of the core basically meets the application requirements of the battery cell, there is still room for improvement in the current collecting capacity of the core. Utility Model Content

[0004] The embodiments of the present application provide a winding core, a battery cell, a battery pack, and an electrical device, which can improve the current collecting capacity 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, a first pole piece, a second pole piece and a third pole piece; the winding core body includes a first pole piece, a second pole piece and a diaphragm arranged 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 along the axial direction of the winding core, the winding core body has a first end and a second end; the first pole piece is arranged at the first end and is connected to the first pole piece; the second pole piece is arranged at the first end and is connected to the second pole piece; the third pole piece is arranged at the second end, and the third pole piece is connected to the first pole piece or the second pole piece.

[0006] In one embodiment, multiple layers of third tabs are bent and stacked to form a third tab region, and the third tab region extends along the circumference of the winding core body into a closed or open ring shape.

[0007] In one embodiment, along the radial direction of the winding core, from the center of the winding core body to the outside, the second end is sequentially provided with a first central hollow lug area and a third tab area.

[0008] In one embodiment, the inner diameter of the third tab region is C, and the outer diameter of the winding core body is A, satisfying: 3%A≤C≤30%A.

[0009] In one embodiment, along the radial direction of the winding core, from the center of the winding core body to the outside, the second end is sequentially provided with a third tab area and a first peripheral hollow tab area.

[0010] In one embodiment, the outer diameter of the third tab region is D, and the outer diameter of the winding core body is A, satisfying: 65%A≤D≤80%A.

[0011] In one embodiment, the third pole tab is connected to the first pole piece, and the plane perpendicular to the axis of the core body is used as the projection plane, and the axial direction of the core body is used as the projection direction. In the projection plane, the projection of the first pole tab before bending and the projection of the third pole tab before bending at least partially overlap; or, the third pole tab is connected to the second pole piece, and the plane perpendicular to the axis of the core body is used as the projection plane, and the axial direction of the core body is used as the projection direction. In the projection plane, the projection of the second pole tab before bending and the projection of the third pole tab before bending at least partially overlap.

[0012] In one embodiment, the winding core further includes a fourth pole tab, which is disposed at the second end of the winding core body. One of the third pole tab and the fourth pole tab is connected to the first pole piece, and the other is connected to the second pole piece.

[0013] In one embodiment, multiple layers of third pole tabs are bent and stacked to form a third pole tab area, and multiple layers of fourth pole tabs are bent and stacked to form a fourth pole tab area. Along the radial direction of the core body, from the center of the core body to the outside, the second end is sequentially provided with the fourth pole tab area, the first middle ring hollow tab area and the third pole tab area. The fourth pole tab area and the third pole tab area extend along the circumference of the core body into closed or open rings, respectively.

[0014] In one embodiment, multiple layers of third pole tabs are bent and stacked to form a third pole tab area, and multiple layers of fourth pole tabs are bent and stacked to form a fourth pole tab area. Along the radial direction of the core body, from the center of the core body to the outside, the second end is sequentially provided with a third central hollow tab area, a fourth pole tab area and a third pole tab area, and the fourth pole tab area and the third pole tab area respectively extend along the circumference of the core body into closed or open rings.

[0015] In one embodiment, the inner diameter of the fourth tab region is J, and the outer diameter of the winding core body is A, satisfying: 3%A≤J≤22%A.

[0016] In one embodiment, multiple layers of third pole tabs are bent and stacked to form a third pole tab area, and multiple layers of fourth pole tabs are bent and stacked to form a fourth pole tab area. Along the radial direction of the core body, from the center of the core body to the outside, the second end is sequentially provided with the fourth pole tab area, the third pole tab area and the third peripheral hollow tab area, and the fourth pole tab area and the third pole tab area respectively extend along the circumference of the core body into closed or open rings.

[0017] In one embodiment, the outer diameter of the third tab region is D, and the outer diameter of the winding core body is A, satisfying the following relationship: 85%A≤D<100%A.

[0018] In one embodiment, the outer diameter of the winding core body is A, the outer diameter of the fourth tab region is I, and the following conditions are met: 25%A≤I≤35%A; and / or the inner diameter of the third tab region is C, and the following conditions are met: 40%A≤C≤75%A.

[0019] In one embodiment, the third electrode tab is connected to the first electrode piece.

[0020] In one embodiment, a plane perpendicular to the axis of the winding core body is used as a projection plane, and the axial direction of the winding core body is used as a projection direction. In the projection plane, the projection of the first tab before bending partially overlaps with the projection of the third tab before bending.

[0021] In one embodiment, the fourth electrode tab is connected to the second electrode piece.

[0022] In one embodiment, a plane perpendicular to the axis of the winding core body is used as a projection plane, and the axial direction of the winding core body is used as a projection direction. In the projection plane, the projection of the second tab before bending at least partially overlaps with the projection of the fourth tab before bending.

[0023] In one embodiment, multiple layers of first pole ears are bent and stacked to form a first pole ear area, and multiple layers of second pole ears are bent and stacked to form a second pole ear area. Along the radial direction of the core body, from the center of the core body to the outside, the first end is sequentially provided with the first pole ear area, the second middle ring hollow ear area and the second pole ear area, and the first pole ear area and the second pole ear area respectively extend along the circumference of the core into closed or open rings.

[0024] In one embodiment, multiple layers of first pole tabs are bent and stacked to form a first pole tab area, and multiple layers of second pole tabs are bent and stacked to form a second pole tab area. Along the radial direction of the winding core body, from the center of the winding core body to the outside, the first end is sequentially provided with a second central hollow tab area, a first pole tab area and a second pole tab area.

[0025] In one embodiment, the inner diameter of the first tab region is M, and the outer diameter of the winding core body is A, satisfying: 3%A≤M≤22%A.

[0026] In an embodiment, the plurality of first tabs are bent and stacked to form the first tab area, the plurality of second tabs are bent and stacked to form the second tab area, and the first end has the first tab area, the second tab area, and the second peripheral empty tab area in sequence from the center of the core body to the outside in the radial direction of the core body.

[0027] In an embodiment, the second tab area has an outer diameter E, and the core body has an outer diameter A, and 85% A≤E<100% A is satisfied.

[0028] In an embodiment, the core body has an outer diameter A, the first tab area has an outer diameter G, and 35% A≤G≤50% A is satisfied; and / or, the second tab area has an inner diameter F, and 60% A≤F≤75% A is satisfied.

[0029] In an embodiment, F-G≥4 mm is satisfied.

[0030] In an embodiment, the second tab area has an outer diameter E, and the second tab area has an inner diameter F, and E-F≥4 mm is satisfied.

[0031] In an embodiment, the first tab is a positive tab, and the second tab is a negative tab.

[0032] In a second aspect, an embodiment of the present application provides an electric core, which includes a shell and the aforementioned core; the shell has a receiving cavity; and the core is arranged in the receiving cavity.

[0033] In a third aspect, an embodiment of the present application provides a battery pack, which includes a box body and the aforementioned electric core, and a plurality of electric cores are arranged in the box body.

[0034] In a fourth aspect, an embodiment of the present application provides a power consumption device, which includes the aforementioned electric core or the aforementioned battery pack, and the battery pack or the electric core supplies power to the power consumption device.

[0035] The beneficial effects of the embodiments of the present application are as follows:

[0036] In the embodiments of the present application, the first tab and the second tab are arranged at one end of the core to collect current of the positive electrode and the negative electrode respectively, and the third tab is arranged at the other end of the core to collect current of one polarity, so that the current collecting area of the tab connected with the third tab is increased, the conduction path of electrons is increased, and the current collecting capacity of the tab is improved. In this way, the current collecting capacity of the core is improved. BRIEF DESCRIPTION OF DRAWINGS

[0037] 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.

[0038] Figure 1 Schematic diagram of the structure of the winding core provided in an embodiment of the present application;

[0039] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0040] Figure 3 is a structural diagram of the second end provided in an embodiment of the present application;

[0041] Figure 4 is a structural diagram of another second end provided in an embodiment of the present application;

[0042] Figure 5 Schematic diagram of the projection relationship between the third tab and the first tab before bending provided in an embodiment of the present application;

[0043] Figure 6 Schematic diagram of the projection relationship between the third tab and the second tab before bending provided in an embodiment of the present application;

[0044] Figure 7 is a structural schematic diagram of another winding core provided in an embodiment of the present application;

[0045] Figure 8 is a structural diagram of yet another second end provided in an embodiment of the present application;

[0046] Figure 9 Schematic diagram of the projection relationship between the fourth electrode tab and the second electrode tab before bending provided in an embodiment of the present application;

[0047] Figure 10 is a structural diagram of the first end provided in an embodiment of the present application;

[0048] Figure 11 is a schematic structural diagram of a battery cell provided in an embodiment of the present application;

[0049] Figure 12 is a schematic structural diagram of a battery pack provided in an embodiment of the present application;

[0050] Figure 13 It is a structural diagram of the electrical equipment provided in the embodiment of the present application.

[0051] Description of reference numerals:

[0052] 001- core;

[0053] 011-first pole lug; 111-first pole lug region; 012-second pole lug; 121-second pole lug region; 013-third pole lug; 131-third pole lug region; 014-fourth pole lug; 141-fourth pole lug region;

[0054] 015 - winding core body; 151 - first pole piece; 152 - second pole piece; 153 - diaphragm; 1541 - first central hollow area; 1542 - second central hollow area; 1543 - third central hollow area; 1544 - first peripheral hollow area; 1545 - second peripheral hollow area; 1546 - third peripheral hollow area; 1547 - first middle ring hollow area; 1548 - second middle ring hollow area;

[0055] 016-middle hole;

[0056] 003-battery cell; 031-housing; 032-cover;

[0057] 004-battery pack; 041-battery box;

[0058] 005-Electrical equipment. DETAILED DESCRIPTION

[0059] 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.

[0060] 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.

[0061] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the specified features. In the description of this application, "plurality" means two or more, unless otherwise specifically specified.

[0062] 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.

[0063] The terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0064] See also Figure 1 , Figure 1 Schematic diagram of the structure of the winding core 001 provided in an embodiment of the present application. The embodiment of the present application provides a winding core 001. The winding core 001 includes a winding core body 015, a first pole tab 011, a second pole tab 012 and a third pole tab 013. The winding core body 015 includes a first pole piece 151, a second pole piece 152 and a diaphragm 153 provided between the first pole piece 151 and the second pole piece 152. Figure 2 As shown, Figure 2 yes Figure 1 Enlarged view of point A in the middle; Figure 2 for Figure 1 The enlarged partial cross-sectional view of the portion shown at A in the figure shows a cross section of a first pole piece 151, a cross section of a second pole piece 152, and a cross section of the diaphragm 153. The polarity of the first pole piece 151 and the second pole piece 152 are opposite. Along the axial direction of the winding core 001, the winding core body 015 has a first end and a second end. The first pole tab 011 is provided at the first end and is connected to the first pole piece 151. The second pole tab 012 is provided at the first end and is connected to the second pole piece 152. The third pole tab 013 is provided at the second end and is connected to the first pole piece 151 or the second pole piece 152.

[0065] It can be understood that the first pole piece 151 , the diaphragm 153 and the second pole piece 152 are stacked and wound in sequence to form the winding core 001 .

[0066] The first electrode piece 151 and the second electrode piece 152 include a coated area coated with an active material and an uncoated area uncoated with the active material. The first electrode tab 011, the second electrode tab 012, and the third electrode tab 013 can be integrally provided as at least a portion of the uncoated area. In other embodiments, the first electrode tab 011 can be separately welded to the first electrode piece 151, the second electrode tab 012 can be separately welded to the second electrode piece 152, and the third electrode tab 013 can be separately welded to either the first electrode piece 151 or the second electrode piece 152.

[0067] In addition, one of the first electrode piece 151 and the second electrode piece 152 is a positive electrode piece, and the other is a negative electrode piece. The polarity of the first electrode tab 011 is opposite to that of the second electrode tab 012, and the polarity of the third electrode tab 013 is the same as that of one of the first electrode tab 011 and the second electrode tab 012, but opposite to that of the other. For example, the first electrode piece 151 is a positive electrode piece, and the second electrode piece 152 is a negative electrode piece. Accordingly, the first electrode tab 011 is a positive electrode piece, and the second electrode tab 012 is a negative electrode piece. The third electrode tab 013 is connected to the first electrode piece 151 and is a positive electrode piece.

[0068] In the embodiment of the present application, a first electrode tab 011 and a second electrode tab 012 are provided at one end of the winding core 001 to collect current for the positive and negative electrodes, respectively. A third electrode tab 013 is provided at the other end of the winding core 001 to collect current for the positive or negative electrode. This increases the current collecting area of ​​the electrode connected to the third electrode tab 013, thereby increasing the number of electron conduction paths and improving the current carrying capacity of the electrode. This improves the current carrying capacity of the winding core 001.

[0069] See also Figure 3 or Figure 4 , Figure 3 is a structural diagram of the second end provided in an embodiment of the present application, Figure 4 This is another structural diagram of the second end provided by an embodiment of the present application. In one embodiment, multiple layers of third tabs 013 are bent and stacked to form a third tab region 131. The third tab region 131 extends along the circumference of the winding core body 015 in a closed or open ring shape.

[0070] Specifically, the tabs are bent toward the end surface of the winding core so that two radially adjacent layers of tabs are stacked along the axial direction of the winding core 001 .

[0071] The third tab area 131 may extend along the circumference of the winding core body 015 into a closed ring shape, such as Figure 3 As shown; the third tab area 131 can also extend along the circumference of the core body 015 into an open ring, that is, the third tab 013 extends along the circumference of the core body 015 into an arc segment. The arc segment can be one segment or multiple segments, and the multiple arc segments are arranged at intervals along the circumference of the core body 015, as shown. Figure 4 shown.

[0072] In this embodiment, by extending the third pole tab 013 along the circumferential direction of the core body 015, on the one hand, the connection length between the third pole tab 013 and the pole piece can be increased, thereby improving the connection strength between the third pole tab 013 and the pole piece, and further improving the structural reliability of the core 001; on the other hand, the area of ​​the third pole tab 013 can be increased, thereby improving the flow area of ​​the core 001, and further improving the flow capacity of the core 001.

[0073] Among them, when the third pole ear area 131 extends into a closed ring along the circumference of the core body 015, the area of ​​the third pole ear 013 can be further increased, thereby increasing the current collecting area of ​​the pole piece connected to the third pole ear 013, so that the electron conduction path is increased, and the current collecting capacity of the pole piece can be improved.

[0074] In addition, when the third pole tab area 131 extends into an open ring along the circumference of the winding core body 015, the obstruction of the connection between the third pole tab 013 and the pole piece to the pole tab flattening can be controlled, thereby facilitating the smooth flattening operation of the third pole tab 013 and thereby improving the pole tab flattening efficiency.

[0075] See also Figure 3 In one embodiment, along the radial direction of the winding core 001 , from the center of the winding core body 015 outward, a first central hollow lug area 1541 and a third tab area 131 are sequentially provided at the second end.

[0076] The empty lug area is an area at the end of the winding core 001 where no lug is provided. Specifically, it is an area at the end of the winding core 001 that is not blocked by the lug after the lug is bent and stacked.

[0077] In addition, the middle hole 016 of the winding core 001 is located at the center of the first central hollow area 1541.

[0078] As can be understood, after the electrode sheet is wound into the core 001, the third electrode tab 013 is parallel to the axis of the core 001, occupying a large height dimension, which has a negative impact on the energy density of the battery cell. For this reason, the third electrode tab 013 is typically bent toward the center of the core 001 to reduce the height space occupied by the third electrode tab 013 in the battery cell. Directly bending the third electrode tab 013 would cause it to block the central hole 016 of the core 001.

[0079] Based on this, in this embodiment, by setting the first central hollow ear area 1541, the third pole ear 013 can be prevented from blocking the middle hole 016 of the winding core 001, thereby ensuring the smooth flow of the electrolyte into or out of the middle hole 016, and further ensuring the wetting efficiency of the winding core 001.

[0080] In addition, the first central hollow area 1541 can also provide expansion space for the third electrode tab 013 that expands due to heat, so as to avoid the third electrode tab 013 from being staggered and subjected to greater stress after thermal expansion, thereby improving the reliability of the battery cell.

[0081] See also Figure 3 In one embodiment, the inner diameter of the third tab region 131 is C, and the outer diameter of the winding core body 015 is A, satisfying the following: 3%A≤C≤30%A. The inner diameter C of the third tab region 131 is the outer diameter of the first central hollow tab region 1541.

[0082] It can be understood that the inner diameter size C of the third pole ear area 131 includes but is not limited to 3%A, 6.2%A, 8.3%A, 10%A, 12.1%A, 13.9%A, 14.5%A, 15%A, 17%A, 18.3%A, 20%A, 22.5%A, 23%A, 25.3%A, 27%A, 28.2%A, 29%A, 29.6%A, and 30%A.

[0083] For example:

[0084] When A is 24mm, C includes but is not limited to 0.72mm, 0.86mm, 1.08mm, 2.13mm, 2.95mm, 3.11mm, 3.71mm, 4.23mm, 5.25mm, 6.78mm, 7.01mm, and 7.2mm;

[0085] When A is 30mm, C includes but is not limited to 0.9mm, 1.06mm, 2.78mm, 3.13mm, 3.85mm, 4.19mm, 5.21mm, 6.23mm, 6.25mm, 7.28mm, 8.29mm, and 9mm;

[0086] When A is 35mm, C includes but is not limited to 1.05mm, 2.06mm, 3.78mm, 4.13mm, 4.85mm, 5.19mm, 5.21mm, 6.23mm, 7.25mm, 8.28mm, 9.29mm, and 10.5mm;

[0087] When A is 40mm, C includes but is not limited to 1.2mm, 2.06mm, 3.78mm, 4.13mm, 5.85mm, 6.19mm, 7.21mm, 8.23mm, 9.75mm, 10.28mm, 11.29mm, and 12mm;

[0088] When A is 45.5mm, C includes but is not limited to 1.365mm, 2.06mm, 3.78mm, 4.13mm, 5.85mm, 6.19mm, 7.21mm, 8.23mm, 9.25mm, 10.28mm, 12.29mm, and 13.65mm.

[0089] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the inner diameter C of the third pole lug area 131 being too small, which causes the third pole lug 013 to block the middle hole 016 of the winding core 001, thereby ensuring the smoothness of the electrolyte flowing into or out of the middle hole 016, and thus ensuring the wetting efficiency of the winding core 001; on the other hand, it is possible to avoid the inner diameter C of the third pole lug area 131 being too large to affect the radial size of the third pole lug 013, thereby not only ensuring the current collecting area of ​​the third pole lug 013 to improve the current collecting capacity of the winding core 001, but also ensuring the welding area of ​​the third pole lug 013, and thus improving the welding stability between the third pole lug 013 and the collecting plate.

[0090] In addition, by limiting the minimum value of the inner diameter C of the third tab region 131 , the first central hollow tab region 1541 can have sufficient space to accommodate the third tab 013 that expands due to heat, thereby preventing the third tabs 013 from intertwining with each other and generating metal debris after thermal expansion.

[0091] In one embodiment, along the radial direction of the winding core 001 , from the center of the winding core body 015 outward, the third tab area 131 and the first peripheral hollow tab area 1544 are sequentially provided at the second end.

[0092] It can be understood that, in combination with the above embodiments, optionally, along the radial direction of the core 001, from the center of the core body 015 to the outside, the second end is sequentially provided with a first central hollow ear area 1541, a third tab area 131 and a first peripheral hollow ear area 1544.

[0093] In this embodiment, by providing the first peripheral hollow ear area 1544, the third electrode ear 013 can be prevented from exceeding the outer periphery of the core body 015 after being flattened, thereby controlling the radial size of the core 001 to facilitate the core 001 to be put into the shell.

[0094] In one embodiment, the outer diameter of the third tab region 131 is D, and the outer diameter of the winding core body 015 is A, satisfying the following: 65%A≤D≤80%A.

[0095] It can be understood that the outer diameter size D of the third tab area 131 includes but is not limited to 65%A, 66.2%A, 68.3%A, 70%A, 72.1%A, 73.9%A, 74.5%A, 75%A, 77%A, 78.3%A, 78.5%A, 79%A, 79.5%A, and 80%A.

[0096] Exemplarily,

[0097] A is 24mm, D includes but is not limited to 15.6mm, 15.86mm, 16.08mm, 16.13mm, 16.95mm, 17.11mm, 17.71mm, 18mm, 18.25mm, 18.38mm, 18.41mm, 19.2mm;

[0098] A is 30mm, D includes but is not limited to 19.5mm, 20.4mm, 20.86mm, 21.08mm, 21.95mm, 22.11mm, 22.71mm, 23mm, 23.25mm, 23.38mm, 23.41mm, 24mm;

[0099] A is 35mm, D includes but is not limited to 22mm, 23mm, 23.38mm, 24.52mm, 25.5mm, 26.08mm, 26.13mm, 26.95mm, 27.11mm, 27.71mm, 28mm;

[0100] A is 40mm, D includes but is not limited to 26.mm, 26.95mm, 27.11mm, 27.71mm, 28mm, 28.38mm, 28.81mm, 29.4mm, 29.75mm, 30.86mm, 31.08mm, 32mm;

[0101] A is 45.5mm, D includes but is not limited to 29.575mm, 30.86mm, 31.08mm, 31.13mm, 32.11mm, 32.71mm, 33mm, 34.25mm, 35.38mm, 36mm, 36.4mm.

[0102] In the embodiment, through the above setting, on the one hand, the outer periphery of the third tab area 131 and the outer periphery of the winding core 001 are arranged along the radial direction of the winding core 001, so that the third tab 013 after being bent can be located in the interval without exceeding the outer periphery of the winding core 001, thereby the outer diameter of the winding core 001 can be controlled, which is beneficial to the smooth entry of the winding core 001 into the shell; on the other hand, the interval between the outer periphery of the third tab area 131 and the outer periphery of the winding core 001 can be avoided to be too large to affect the area of the third tab 013, so that the current collecting capacity and internal resistance of the third tab 013 can meet the demand.

[0103] Please refer to Figure 5 or Figure 6 , Figure 5 is a schematic diagram of the projection relationship of the third tab 013 and the first tab 011 before being bent, Figure 6 Schematic diagram of the projection relationship between the third pole tab 013 and the second pole tab 012 before bending provided by an embodiment of the present application. In one embodiment, the third pole tab 013 is connected to the first pole piece 151. The plane perpendicular to the axis of the winding core body 015 is used as the projection plane, and the axial direction of the winding core body 015 is used as the projection direction. In the projection plane, the projection of the first pole tab 011 before bending and the projection of the third pole tab 013 before bending at least partially overlap, as shown in FIG. Figure 5 Alternatively, the third pole tab 013 is connected to the second pole piece 152, and the plane perpendicular to the axis of the winding core body 015 is used as the projection plane, and the axial direction of the winding core body 015 is used as the projection direction. In the projection plane, the projection of the second pole tab 012 before bending and the projection of the third pole tab 013 before bending at least partially overlap, as shown in FIG. Figure 6 shown.

[0104] Optionally, the third pole tab 013 is connected to the first pole piece 151, and in the projection plane, the projection of the first pole tab 011 before bending falls within the projection of the third pole tab 013 before bending; or, the third pole tab 013 is connected to the second pole piece 152, and the projection of the second pole tab 012 before bending falls within the projection of the third pole tab 013 before bending.

[0105] Specifically, the projection of the base of the first pole tab 011 falls within the projection of the base of the third pole tab 013, or the projection of the base of the second pole tab 012 falls within the projection of the base of the third pole tab 013. The base of the pole tab is where the pole tab connects to the coating area.

[0106] In this embodiment, the above arrangement enables the third electrode tab 013 to have opposite locations along the axial direction of the winding core 001 from the first electrode tab 011 or the second electrode tab 012 connected to the same electrode sheet. This allows the third electrode tab 013 to collect current and then directly move along the axial direction of the winding core 001 to transfer current to the first electrode tab 011 or the second electrode tab 012 connected to the same electrode sheet, thereby shortening the current collection path of the winding core 001. This improves the current collection capacity of the winding core 001.

[0107] See also Figure 7 , Figure 7 This is a schematic diagram of the structure of another winding core 001 provided in an embodiment of the present application. In one embodiment, winding core 001 further includes a fourth electrode tab 014. Fourth electrode tab 014 is disposed at the second end of winding core body 015. One of third electrode tab 013 and fourth electrode tab 014 is connected to first electrode piece 151, and the other is connected to second electrode piece 152.

[0108] Exemplarily, the third tab 013 is connected to the first tab 151, and the fourth tab 014 is connected to the second tab 152. Moreover, the first tab 011 is arranged closer to the center of the winding core 001 than the second tab 012, and the fourth tab 014 is arranged closer to the center of the winding core 001 than the third tab 013.

[0109] Further, the first tab 151 is a positive tab, and the second tab 152 is a negative tab. Correspondingly, the first tab 011 is a positive tab, and the second tab 012 is a negative tab.

[0110] In the embodiment, by arranging the first tab 011 and the second tab 012 at one end of the winding core 001 to respectively collect the positive and negative currents, and arranging the third tab 013 and the fourth tab 014 at the other end of the winding core 001 to respectively collect the positive and negative currents, the current collection area of the two kinds of tabs of the winding core 001 can be increased, so that the conduction path of the electrons is increased, and thus the current collection capability of the first tab 151 and the second tab 152 can be improved. In this way, the current collection capability of the winding core 001 can be further improved.

[0111] Please refer to Figure 8 , Figure 8 is a structural schematic view of the second end provided by the embodiment of the present application. In an embodiment, the plurality of third tabs 013 are folded and stacked to form a third tab area 131. The plurality of fourth tabs 014 are folded and stacked to form a fourth tab area 141. Along the radial direction of the winding core body 015, from the center of the winding core body 015 outward, the second end is sequentially provided with the fourth tab area 141, the first middle annular tab area 1547, and the third tab area 131, and the fourth tab area 141 and the third tab area 131 respectively extend along the circumferential direction of the winding core body 015 as a closed or non-closed ring.

[0112] It can be understood that the fourth tab area 141 can extend along the circumferential direction of the winding core body 015 as a closed ring; the fourth tab area 141 can also extend along the circumferential direction of the winding core body 015 as a non-closed ring, that is, the fourth tab 014 extends along the circumferential direction of the winding core body 015 as an arc segment. The arc segment can be one segment or multiple segments, and the multiple arc segments are arranged at intervals along the circumferential direction of the winding core body 015.

[0113] Among them, the insulation isolation of the third tab 013 and the fourth tab 014 can be spatially insulated by the first middle annular tab area 1547, or an insulating member can be arranged between the third tab 013 and the fourth tab 014 to achieve insulation isolation.

[0114] In this embodiment, by extending the third pole tab 013 and the fourth pole tab 014 along the circumferential direction of the core body 015, on the one hand, the connection length between the third pole tab 013 and the fourth pole tab 014 and the pole piece can be increased, thereby improving the connection strength between the third pole tab 013 and the fourth pole tab 014 and the pole piece, thereby improving the structural reliability of the core 001; on the other hand, the area of ​​the third pole tab 013 and the fourth pole tab 014 can be increased respectively, thereby improving the flow area of ​​the core 001, thereby improving the flow capacity of the core 001.

[0115] In addition, by providing the first mid-ring hollow ear area 1547, a gap can be created between the third pole ear 013 and the fourth pole ear 014 to provide expansion space for the third pole ear 013 and the fourth pole ear 014 that expand due to heat, thereby avoiding excessive pressure between the third pole ear 013 and the fourth pole ear 014 due to thermal expansion, thereby ensuring the reliability of insulation between the third pole ear 013 and the fourth pole ear 014.

[0116] See also Figure 8 In one embodiment, multiple layers of third tabs 013 are bent and stacked to form a third tab region 131. Multiple layers of fourth tabs 014 are bent and stacked to form a fourth tab region 141. Along the radial direction of the core body 015, from the center of the core body 015 outward, the second end is sequentially provided with a third central hollow tab region 1543, a fourth tab region 141, and a third tab region 131. The fourth tab region 141 and the third tab region 131 each extend along the circumference of the core body 015 in a closed or open ring shape.

[0117] In this embodiment, by setting the third central hollow ear area 1543, the fourth pole ear 014 can be prevented from blocking the middle hole of the core 001, thereby improving the smoothness of the electrolyte flowing out of or into the middle hole of the core 001, thereby ensuring the wetting efficiency of the core 001.

[0118] See also Figure 8 In one embodiment, the inner diameter of the fourth tab region 141 is J, and the outer diameter of the winding core body 015 is A, satisfying: 3%A≤J≤22%A.

[0119] It can be understood that the inner diameter size J of the third pole ear area 131 includes but is not limited to 3%A, 3.6%A, 43%A, 5%A, 6.2%A, 8.3%A, 10%A, 12.1%A, 13.9%A, 14.5%A, 15%A, 17%A, 18.3%A, 20%A, 21%A, 21.3%A, 21.5%A, and 22%A.

[0120] For example:

[0121] When A is 24 mm, J includes but is not limited to 0.72 mm, 0.86 mm, 1.08 mm, 1.65 mm, 2.13 mm, 2.95 mm, 3.11 mm, 3.71 mm, 4.23 mm, 5.25 mm, 5.78 mm, and 5.82 mm;

[0122] When A is 30 mm, J includes but is not limited to 0.9 mm, 1.06 mm, 2.78 mm, 3.13 mm, 3.85 mm, 4.19 mm, 5.21 mm, 6.23 mm, 6.25 mm, 6.38 mm, 6.59 mm, and 6.6 mm;

[0123] When A is 35 mm, J includes but is not limited to 1.05 mm, 2.06 mm, 3.78 mm, 4.13 mm, 4.85 mm, 5.19 mm, 5.21 mm, 6.23 mm, 7.25 mm, 7.38 mm, 7.59 mm, and 7.7 mm;

[0124] When A is 40 mm, J includes but is not limited to 1.2 mm, 2.06 mm, 3.78 mm, 4.13 mm, 5.85 mm, 6.19 mm, 7.21 mm, 7.23 mm, 7.75 mm, 8.28 mm, 8.5 mm, and 8.8 mm;

[0125] When A is 45.5mm, J includes but is not limited to 1.365mm, 2.06mm, 3.78mm, 4.13mm, 5.85mm, 6.19mm, 7.21mm, 8.23mm, 9.25mm, 9.88mm, 10mm, and 10.01mm.

[0126] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the inner diameter J of the fourth pole lug area 141 being too small, which causes the fourth pole lug 014 to block the middle hole 016 of the winding core 001, thereby ensuring the smoothness of the electrolyte flowing into or out of the middle hole 016, and thus ensuring the infiltration efficiency of the winding core 001; on the other hand, it is possible to avoid the inner diameter J of the fourth pole lug area 141 being too large to affect the radial size of the fourth pole lug 014, thereby not only ensuring the current collecting area of ​​the fourth pole lug 014 to improve the current collecting capacity of the winding core 001, but also ensuring the welding area of ​​the fourth pole lug 014, and thus improving the welding stability between the fourth pole lug 014 and the collecting plate.

[0127] In addition, by limiting the minimum value of the inner diameter J of the fourth tab region 141 , the third central hollow region 1543 can have sufficient space to accommodate the fourth tab 014 , thereby preventing the fourth tab 014 from crossing the third central hollow region 1543 after bending and generating metal debris.

[0128] See also Figure 8 In an embodiment, the multi-layer third tab 013 is bent and laminated to form a third tab area 131. The multi-layer fourth tab 014 is bent and laminated to form a fourth tab area 141. Along the radial direction of the core body 015, from the center of the core body 015 outward, the second end is sequentially provided with the fourth tab area 141, the third tab area 131, and the third peripheral empty tab area 1546. The fourth tab area 141 and the third tab area 131 respectively extend along the circumferential direction of the core body 015 to be closed or not closed annular.

[0129] It can be understood that in combination with the foregoing embodiments, along the radial direction of the core 001, from the center of the core body 015 outward, the second end is sequentially provided with the third central empty tab area 1543, the fourth tab area 141, the first middle ring empty tab area 1547, the third tab area 131, and the third peripheral empty tab area 1546.

[0130] In the present embodiment, by providing the third peripheral empty tab area 1546, after the third tab 013 is rubbed flat, the third tab 013 can be prevented from exceeding the outer circumference of the core body 015, and thus the radial dimension of the core 001 can be controlled to facilitate the core 001 into the shell.

[0131] Please refer to Figure 8 In an embodiment, the outer diameter size of the third tab area 131 is D, and the outer diameter of the core body 015 is A, which satisfies: 85% A≤D<100% A.

[0132] It can be understood that the outer diameter size D of the third tab area 131 includes but is not limited to 85% A, 86.2% A, 88.3% A, 90% A, 92.1% A, 93.9% A, 94.5% A, 95% A, 97% A, 98.3% A, 98.5% A, 99% A, 99.5% A, 99.8% A.

[0133] Exemplarily:

[0134] When A is 24mm, D includes but is not limited to 20.4mm, 20.86mm, 21.08mm, 21.13mm, 21.95mm, 22.11mm, 22.71mm, 23mm, 23.25mm, 23.38mm, 23.41mm, 23.5mm;

[0135] When A is 30mm, D includes but is not limited to 25.5mm, 2586mm, 26.08mm, 26.13mm, 26.95mm, 27.11mm, 27.71mm, 28mm, 28.25mm, 28.38mm, 28.81mm, 29.4mm;

[0136] A is 35mm, D includes but is not limited to 29.75mm, 30.86mm, 31.08mm, 31.13mm, 31.95mm, 32.11mm, 32.71mm, 33mm, 33.25mm, 33.38mm, 34mm, 34.3mm; A is 40mm, D includes but is not limited to 34mm, 34.86mm, 35.08mm, 35.13mm, 35.95mm, 36.11mm, 36.71mm, 37mm, 38.25mm, 38.38mm, 39mm, 39.2mm; A is 45.5mm, D includes but is not limited to 38.675mm, 39mm, 39.08mm, 40.13mm, 40.95mm, 41.11mm, 41.71mm, 42mm, 43.25mm, 43.38mm, 44mm, 44.59mm.

[0137] In the embodiment, through the above setting, on the one hand, the outer periphery of the third tab area 131 and the outer periphery of the winding core 001 are arranged along the radial direction of the winding core 001, so that the third tab 013 after being bent can be located in the interval without exceeding the outer periphery of the winding core 001, thereby the outer diameter of the winding core 001 can be controlled, which is beneficial to the smooth entry of the winding core 001 into the shell; on the other hand, the interval between the outer periphery of the third tab area 131 and the outer periphery of the winding core 001 can be avoided to be too large to affect the area of the third tab 013, so that the current collecting capacity and internal resistance of the third tab 013 can meet the demand.

[0138] Please refer to Figure 8 In an embodiment, the outer diameter of the winding core body 015 is A, the outer diameter size of the fourth tab area 141 is I, and 25% A≤I≤35% A is satisfied; and / or, the inner diameter size of the third tab area 131 is C, and 40% A≤C≤75% A is satisfied.

[0139] Specifically, the outer diameter size of the fourth tab area 141 is I, and 25% A≤I≤35% A is satisfied, or the inner diameter size of the third tab area 131 is C, and 40% A≤C≤75% A is satisfied, or the outer diameter size of the fourth tab area 141 is I, and 25% A≤I≤35% A is satisfied, and the inner diameter size of the third tab area 131 is C, and 40% A≤C≤75% A is satisfied.

[0140] The outer diameter size I of the fourth tab area 141 includes but is not limited to 25% A, 25.5% A, 25.9% A, 26% A, 26.8% A, 27% A, 27.33% A, 28% A, 30% A, 31% A, 32% A, 33% A, 34% A, 34.5% A, 35% A.

[0141] Exemplarily,

[0142] A is 24 mm, I includes but is not limited to 6 mm, 6.06 mm, 6.2 mm, 6.5 mm, 6.95 mm, 7.11 mm, 7.21 mm, 7.3 mm, 7.5 mm, 7.8 mm, 8.02 mm, 8.4 mm;

[0143] A is 30 mm, I includes but is not limited to 7.5 mm, 7.6 mm, 8.2 mm, 8.5 mm, 8.95 mm, 9.11 mm, 9.21 mm, 9.3 mm, 9.5 mm, 9.8 mm, 10.41 mm, 10.5 mm;

[0144] A is 35 mm, I includes but is not limited to 8.75 mm, 8.9 mm, 9.2 mm, 9.5 mm, 9.95 mm, 10.11 mm, 10.21 mm, 10.8 mm, 11.05 mm, 11.8 mm, 12 mm, 12.25 mm;

[0145] A is 40 mm, I includes but is not limited to 10 mm, 10.1 mm, 10.2 mm, 10.5 mm, 10.95 mm, 11.11 mm, 11.21 mm, 11.8 mm, 12.05 mm, 12.8 mm, 13 mm, 14 mm;

[0146] A is 45.5 mm, I includes but is not limited to 11.375 mm, 12.1 mm, 12.2 mm, 12.5 mm, 12.95 mm, 13.11 mm, 13.21 mm, 13.6 mm, 13.65 mm, 13.8 mm, 15 mm, 15.925 mm.

[0147] In addition, the inner diameter C of the third tab area includes but is not limited to 40% A, 45.5% A, 50% A, 53.33% A, 55.9% A, 56% A, 58% A, 60% A, 63% A, 65% A, 68% A, 70% A, 71% A, 74.2% A, 75% A.

[0148] Exemplarily:

[0149] A is 24 mm, C includes but is not limited to 9.6 mm, 10.06 mm, 11.2 mm, 12.5 mm, 12.95 mm, 13.11 mm, 14.21 mm, 15.3 mm, 16.5 mm, 16.8 mm, 17.41 mm, 18 mm;

[0150] When A is 30mm, C includes but is not limited to 12mm, 13.6mm, 14.2mm, 15.5mm, 16.95mm, 17.11mm, 17.21mm, 18.3mm, 19.5mm, 20.8mm, 21.41mm, and 22.5mm;

[0151] When A is 35mm, C includes but is not limited to 14mm, 15.9mm, 16.2mm, 17.5mm, 18.95mm, 20.11mm, 21.21mm, 22.8mm, 23.05mm, 24.8mm, 25mm, and 26.25mm;

[0152] When A is 40mm, C includes but is not limited to 16mm, 17.1mm, 18.2mm, 19.5mm, 20.95mm, 22.11mm, 23.21mm, 24.8mm, 26.05mm, 27.8mm, 29mm, and 30mm;

[0153] When A is 45.5mm, C includes but is not limited to 18.2mm, 19.1mm, 20.2mm, 21.5mm, 22.95mm, 23.11mm, 25.21mm, 26.8mm, 30.05mm, 31.8mm, 34mm, and 34.125mm.

[0154] In this embodiment, by limiting the outer diameter size I of the fourth pole lug area 141, it is possible to avoid the outer diameter size of the fourth pole lug area 141 being too large and affecting the arrangement of the third pole lug area 131; by limiting the inner diameter size C of the third pole lug area 131, it is possible to avoid the inner diameter size being too small and affecting the arrangement of the fourth pole lug 014; and by limiting the outer diameter size I of the fourth pole lug area 141 and the inner diameter size C of the third pole lug area 131, it is possible to ensure that there is a sufficient spacing between the fourth pole lug 014 and the third pole lug 013, so that the fourth pole lug 014 and the third pole lug are insulated and isolated by the spacing, or an insulating member is provided in the spacing.

[0155] In addition, by combining the aforementioned embodiments with the restrictions on the inner diameter of the fourth tab region 141 and the outer diameter of the third tab region 131 , the third tab 013 and the fourth tab 014 can meet the current collecting requirements of the winding core 001 and have appropriate internal resistance.

[0156] See also Figure 4 In one embodiment, the third electrode tab 013 is connected to the first electrode piece 151. Taking a plane perpendicular to the axis of the winding core body 015 as the projection plane, and the axial direction of the winding core body 015 as the projection direction, in the projection plane, the projection of the first electrode tab 011 before bending partially overlaps with the projection of the third electrode tab 013 before bending.

[0157] The first pole tab 011 is positioned closer to the center of the winding core 001 than the second pole tab 012. The fourth pole tab 014 is positioned closer to the center of the winding core 001 than the third pole tab 013. Along the axial direction of the winding core 001, the side of the first pole tab region 111 closer to the periphery of the winding core 001 is positioned opposite the side of the third pole tab region 131 closer to the center of the winding core 001.

[0158] In this embodiment, the above arrangement allows the third tab 013 and the first tab 011 to have opposing portions along the axial direction of the winding core 001. This allows the third tab 013 to collect current and then directly move along the axial direction of the winding core 001 to transfer the current to the first tab 011, thereby shortening the current collection path of the winding core 001. This improves the current collection capacity of the winding core 001.

[0159] See also Figure 9 , Figure 9 This is a schematic diagram of the projection relationship between the fourth electrode tab 014 and the second electrode tab 012 before bending, according to an embodiment of the present application. In one embodiment, the fourth electrode tab 014 is connected to the second electrode piece 152. With the plane perpendicular to the axis of the winding core 015 as the projection plane and the axial direction of the winding core 015 as the projection direction, the projection of the second electrode tab 012 before bending at least partially overlaps with the projection of the fourth electrode tab 014 before bending.

[0160] It can be understood that the projection of the root of the second electrode tab 012 partially overlaps with the projection of the root of the fourth electrode tab 014 .

[0161] The first pole tab 011 is positioned closer to the center of the winding core 001 than the second pole tab 012. The fourth pole tab 014 is positioned closer to the center of the winding core 001 than the third pole tab 013. Along the axial direction of the winding core 001, the side of the fourth pole tab region 141 closer to the periphery of the winding core 001 is positioned opposite the side of the second pole tab region 121 closer to the center of the winding core 001.

[0162] In this embodiment, the above arrangement allows the fourth tab 014 and the second tab 012 to have opposing portions along the axial direction of the winding core 001. This allows the fourth tab 014 to collect current and then directly move along the axial direction of the winding core 001 to transfer the current to the second tab 012, thereby shortening the current collection path of the winding core 001. This improves the current collection capacity of the winding core 001.

[0163] See also Figure 10 , Figure 10This is a schematic diagram of the structure of the first end provided by an embodiment of the present application. In one embodiment, multiple layers of first tabs 011 are bent and stacked to form a first tab region 111. Multiple layers of second tabs 012 are bent and stacked to form a second tab region 121. Along the radial direction of the core body 015, from the center of the core body 015 outward, the first end is sequentially provided with the first tab region 111, the second mid-ring hollow tab region 1548, and the second tab region 121. The first tab region 111 and the second tab region 121 each extend along the circumference of the core 001 in a closed or open ring shape.

[0164] The first tab region 111 and the second tab region 121 may extend along the circumference of the winding core body 015 to form a closed ring. Figure 10 As shown, the first tab region 111 and the second tab region 121 may also extend along the circumference of the core body 015 into an open ring shape, that is, the first tab region 111 and the second tab region 121 extend along the circumference of the core body 015 into arc segments. The arc segments may be one or multiple segments, and the multiple arc segments are spaced apart along the circumference of the core body 015.

[0165] In this embodiment, by extending the first pole lug area 111 and the second pole lug area 121 along the circumferential direction of the winding core body 015, not only the connection length between the first pole lug 011 and the first pole piece 151 and the connection length between the second pole lug 012 and the second pole piece 152 can be increased to improve the positional stability of the first pole lug 011 and the second pole lug 012; the area of ​​the first pole lug 011 and the second pole lug 012 can also be increased, thereby improving the current collecting capacity of the first pole lug 011 and the second pole lug 012, and further improving the current collecting capacity of the winding core 001.

[0166] See also Figure 10 In one embodiment, multiple layers of first tabs 011 are bent and stacked to form a first tab region 111. Multiple layers of second tabs 012 are bent and stacked to form a second tab region 121. Along the radial direction of the winding core 015, from the center of the winding core 015 outward, the first end is sequentially provided with a second central hollow tab region 1542, the first tab region 111, and the second tab region 121.

[0167] In this embodiment, by providing the second central hollow ear area 1542, the first electrode ear 011 can be prevented from blocking the middle hole of the winding core 001, thereby ensuring the smooth flow of the electrolyte into or out of the middle hole, and further ensuring the wetting efficiency of the winding core 001.

[0168] See also Figure 10 In one embodiment, the inner diameter of the first tab region 111 is M, and the outer diameter of the winding core body 015 is A, satisfying: 3%A≤M≤22%A.

[0169] It can be understood that the inner diameter size M of the third pole ear area 131 includes but is not limited to 3%A, 3.6%A, 43%A, 5%A, 6.2%A, 8.3%A, 10%A, 12.1%A, 13.9%A, 14.5%A, 15%A, 17%A, 18.3%A, 20%A, 21%A, 21.3%A, 21.5%A, and 22%A.

[0170] For example:

[0171] When A is 24 mm, M includes but is not limited to 0.72 mm, 0.86 mm, 1.08 mm, 1.65 mm, 2.13 mm, 2.95 mm, 3.11 mm, 3.71 mm, 4.23 mm, 5.25 mm, 5.78 mm, and 5.82 mm;

[0172] When A is 30 mm, M includes but is not limited to 0.9 mm, 1.06 mm, 2.78 mm, 3.13 mm, 3.85 mm, 4.19 mm, 5.21 mm, 6.23 mm, 6.25 mm, 6.38 mm, 6.59 mm, and 6.6 mm;

[0173] When A is 35mm, M includes but is not limited to 1.05mm, 2.06mm, 3.78mm, 4.13mm, 4.85mm, 5.19mm, 5.21mm, 6.23mm, 7.25mm, 7.38mm, 7.59mm, and 7.7mm;

[0174] When A is 40 mm, M includes but is not limited to 1.2 mm, 2.06 mm, 3.78 mm, 4.13 mm, 5.85 mm, 6.19 mm, 7.21 mm, 7.23 mm, 7.75 mm, 8.28 mm, 8.5 mm, and 8.8 mm;

[0175] When A is 45.5mm, M includes but is not limited to 1.365mm, 2.06mm, 3.78mm, 4.13mm, 5.85mm, 6.19mm, 7.21mm, 8.23mm, 9.25mm, 9.88mm, 10mm, and 10.01mm.

[0176] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the inner diameter M of the first pole lug area 111 being too small, which causes the first pole lug 011 to block the middle hole 016 of the winding core 001, thereby ensuring the smoothness of the electrolyte flowing into or out of the middle hole 016, and thus ensuring the infiltration efficiency of the winding core 001; on the other hand, it is possible to avoid the inner diameter M of the first pole lug area 111 being too large to affect the radial size of the first pole lug 011, thereby not only ensuring the current collecting area of ​​the first pole lug 011 to improve the current collecting capacity of the winding core 001, but also ensuring the welding area of ​​the first pole lug 011, and thus improving the welding stability between the first pole lug 011 and the collecting plate.

[0177] In addition, by limiting the minimum value of the inner diameter M of the first tab area 111, the second central hollow tab area 1542 can have sufficient space to accommodate the first tab 011 that expands due to heat, thereby preventing the first tab 011 from interlacing in the second central hollow tab area 1542 after thermal expansion and generating metal debris.

[0178] See also Figure 10 In one embodiment, multiple layers of first tabs 011 are bent and stacked to form a first tab region 111. Multiple layers of second tabs 012 are bent and stacked to form a second tab region 121. Along the radial direction of the winding core 015, from the center of the winding core 015 outward, the first end is sequentially provided with the first tab region 111, the second tab region 121, and the second peripheral hollow tab region 1545.

[0179] In combination with the above-mentioned embodiment, optionally, along the radial direction of the core 001, from the center of the core body 015 to the outside, the second end is sequentially provided with a second central hollow ear area 1542, a first pole ear area 111, a second middle ring hollow ear area 1548, a second pole ear area 121 and a second peripheral hollow ear area 1545.

[0180] In this embodiment, by providing the second peripheral hollow ear area 1545, the second electrode ear 012 can be prevented from exceeding the outer periphery of the core body 015 after the second electrode ear 012 is flattened, thereby controlling the radial size of the core 001 to facilitate the core 001 to be put into the shell.

[0181] See also Figure 10 In one embodiment, the outer diameter of the second tab region 121 is E, and the outer diameter of the winding core body 015 is A, satisfying: 85%A≤E<100%A.

[0182] It can be understood that the outer diameter size E of the second tab area 121 includes but is not limited to 85%A, 86.2%A, 88.3%A, 90%A, 92.1%A, 93.9%A, 94.5%A, 95%A, 97%A, 98.3%A, 98.5%A, 99%A, 99.5%A, and 99.8%A.

[0183] For example:

[0184] When A is 24mm, E includes but is not limited to 20.4mm, 20.86mm, 21.08mm, 21.13mm, 21.95mm, 22.11mm, 22.71mm, 23mm, 23.25mm, 23.38mm, 23.41mm, and 23.52mm;

[0185] When A is 30mm, E includes but is not limited to 25.5mm, 2586mm, 26.08mm, 26.13mm, 26.95mm, 27.11mm, 27.71mm, 28mm, 28.25mm, 28.38mm, 28.81mm, and 29.4mm;

[0186] When A is 35mm, E includes but is not limited to 29.75mm, 30.86mm, 31.08mm, 31.13mm, 31.95mm, 32.11mm, 32.71mm, 33mm, 33.25mm, 33.38mm, 34mm, and 34.3mm; when A is 40mm, E includes but is not limited to 34mm, 34.86mm, 35.08mm, 35.13mm, and 35.95mm m, 36.11mm, 36.71mm, 37mm, 38.25mm, 38.38mm, 39mm, 39.2mm; when A is 45.5mm, E includes but is not limited to 38.675mm, 39mm, 39.08mm, 40.13mm, 40.95mm, 41.11mm, 41.71mm, 42mm, 43.25mm, 43.38mm, 44mm, and 44.59mm.

[0187] In this embodiment, through the above-mentioned arrangement, on the one hand, the outer periphery of the second pole lug area 121 and the outer periphery of the core 001 can be arranged at a radial interval along the core 001, so that the bent second pole lug 012 can be located in the interval without exceeding the outer periphery of the core 001, thereby controlling the outer diameter of the core 001, which is conducive to the smooth insertion of the core 001 into the shell; on the other hand, it can avoid the outer periphery of the second pole lug area 121 and the outer periphery of the core 001 being too large to affect the area of ​​the second pole lug 012, so that the current collecting capacity and internal resistance of the second pole lug 012 can meet the requirements.

[0188] In one embodiment, the outer diameter of the winding core body 015 is A, the outer diameter of the first tab region 111 is G, and the following conditions are met: 35% A≤G≤50%A; and / or the inner diameter of the second tab region 121 is F, and the following conditions are met: 60% A≤F≤75%A.

[0189] Specifically, the outer diameter dimension G of the first pole tab region 111 satisfies: 35%A≤G≤50%A; or, the inner diameter dimension F of the second pole tab region 121 satisfies: 60%A≤F≤75%A; or, the outer diameter dimension G of the first pole tab region 111 satisfies: 35%A≤G≤50%A, and the inner diameter dimension F of the second pole tab region 121 satisfies: 60%A≤F≤75%A.

[0190] Among them, the outer diameter size G of the first pole ear area 111 includes but is not limited to 35%A, 35.5%A, 36.9%A, 37%A, 38.8%A, 40%A, 42.33%A, 44.8%A, 45%A, 46.1%A, 47.2%A, 48.3%A, 49.4%A, 49.5%A, and 50%A.

[0191] For example:

[0192] When A is 24mm, G includes but is not limited to 8.4mm, 8.9mm, 9.2mm, 9.5mm, 9.95mm, 10.11mm, 10.21mm, 10.8mm, 11.05mm, 11.8mm, 11.9mm, and 12mm;

[0193] When A is 30mm, G includes but is not limited to 10.5mm, 10.95mm, 11.11mm, 11.21mm, 11.8mm, 12.05mm, 12.8mm, 13mm, 14mm, 14.5mm, 14.8mm, and 15mm;

[0194] When A is 35mm, G includes but is not limited to 12.25mm, 12.95mm, 13.11mm, 13.21mm, 13.8mm, 13.9mm, 15mm, 15.925mm, 16.05mm, 16.8mm, 17mm, and 17.5mm;

[0195] When A is 40mm, G includes but is not limited to 14mm, 14.1mm, 15.2mm, 16mm, 16.95mm, 17.11mm, 17.61mm, 18mm, 18.05mm, 18.8mm, 19mm, and 20mm;

[0196] When A is 45.5mm, G includes but is not limited to 15.925mm, 16.1mm, 16.2mm, 16.5mm, 17mm, 17.11mm, 17.8mm, 18.05mm, 18.8mm, 19mm, 20mm, and 22.75mm.

[0197] In addition, the inner diameter size F of the second tab area 121 includes but is not limited to 60%A, 61.5%A, 63%A, 64.33%A, 65.9%A, 66%A, 68%A, 69%A, 70.3%A, 71.5%A, 72.8%A, 73%A, 74%A, 74.2%A, and 75%A.

[0198] For example:

[0199] When A is 24mm, F includes but is not limited to 14.4mm, 14.6mm, 14.92mm, 15mm, 15.15mm, 15.81mm, 16mm, 16.3mm, 16.5mm, 16.8mm, 17.41mm, and 18mm;

[0200] When A is 30mm, F includes but is not limited to 18mm, 18.1mm, 18.2mm, 18.5mm, 19mm, 19.11mm, 19.21mm, 20.3mm, 10.5mm, 21.8mm, 21.91mm, and 22.5mm;

[0201] When A is 35mm, F includes but is not limited to 21mm, 21.9mm, 22.2mm, 22.5mm, 22.95mm, 23.11mm, 24.21mm, 24.8mm, 25.05mm, 25.8mm, 26mm, and 26.25mm;

[0202] When A is 40mm, F includes but is not limited to 24mm, 24.1mm, 25.2mm, 26.5mm, 26.95mm, 27.11mm, 27.21mm, 27.8mm, 28.05mm, 28.8mm, 29mm, and 30mm;

[0203] When A is 45.5mm, F includes but is not limited to 27.3mm, 28.1mm, 29.2mm, 29.5mm, 29.95mm, 30.11mm, 31.21mm, 31.8mm, 32.05mm, 33.8mm, 34mm, and 34.125mm.

[0204] In this embodiment, by limiting the outer diameter size G of the first pole lug area 111, it is possible to avoid the outer diameter size of the first pole lug area 111 being too large and affecting the arrangement of the second pole lug area 121; by limiting the inner diameter size F of the second pole lug area 121, it is possible to avoid the inner diameter size being too small and affecting the arrangement of the first pole lug 011; and by limiting the outer diameter size G of the first pole lug area 111 and the inner diameter size F of the second pole lug area 121, it is possible to ensure that there is a sufficient spacing between the first pole lug 011 and the second pole lug 012, so that the first pole lug 011 and the second pole lug are insulated and isolated by the spacing, or an insulating member is provided in the spacing.

[0205] In addition, by combining the aforementioned embodiments with the restrictions on the inner diameter of the first tab region 111 and the outer diameter of the second tab region 121 , the first tab 011 and the second tab 012 can meet the current collecting requirements of the winding core 001 and have appropriate internal resistance.

[0206] Optionally, the third electrode tab 013 is connected to the first electrode piece 151, and the inner diameter C of the third electrode tab region 131 is no greater than the outer diameter G of the first electrode tab region 111. Thus, after collecting current, the third electrode tab 013 can directly move along the axial direction of the winding core 001 to transfer current to the first electrode tab 011, thereby shortening the current collection path and enhancing the current collection effect.

[0207] Similarly, the fourth electrode tab 014 is connected to the second electrode piece 152, and the inner diameter F of the second electrode tab region 121 is no greater than the outer diameter I of the fourth electrode tab region 141. As a result, after collecting current, the fourth electrode tab 014 can directly move along the axial direction of the winding core 001 to transfer current to the second electrode tab 012, thereby shortening the current collection path and enhancing the current collection effect.

[0208] In one embodiment, FG ≥ 4 mm.

[0209] Illustratively, the difference between the inner diameter F of the second tab region 121 and the outer diameter G of the first tab region 111 includes but is not limited to 4 mm, 4.1 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.8 mm, and 5 mm.

[0210] In this embodiment, through the above-mentioned limitation, there can be at least a 4 mm gap between the inner diameter F of the second pole tab area 121 and the outer diameter G of the first pole tab area 111, so that the first pole tab 011 and the second pole tab can be insulated and isolated through this gap, or the gap can have enough space to set the insulating part, so as to improve the convenience of configuring the insulating part.

[0211] In one embodiment, the outer diameter of the second tab region 121 is E, and the inner diameter of the second tab region 121 is F, satisfying: EF ≥ 4 mm.

[0212] Illustratively, the difference between the outer diameter E of the second tab region 121 and the inner diameter F of the second tab region 121 includes but is not limited to 4 mm, 4.1 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.8 mm, and 5 mm.

[0213] In this embodiment, through the above-mentioned limitation, the second pole tab 012 can have a sufficient area, which not only enables the current collecting capacity of the second pole tab 012 to meet the current collecting requirements of the winding core 001, but also enables the second pole tab 012 to have a suitable welding area, thereby improving the operability of the welding connection between the second pole tab 012 and the collecting plate.

[0214] See also Figure 11 , Figure 11 Schematic diagram of the structure of a battery cell 003 provided in an embodiment of the present application. Accordingly, an embodiment of the present application provides a battery cell 003 comprising a housing 031 and the aforementioned winding core 001. Housing 031 has a receiving cavity. Winding core 001 is disposed in the receiving cavity.

[0215] It can be understood that the battery cell 003 further includes a shell 031 and a cover plate 032. The shell 031 and the cover plate 032 cover each other to form a receiving cavity, and the winding core 001 is disposed in the receiving cavity.

[0216] In this embodiment, by adopting the aforementioned winding core 001, the current transmission inside the battery cell 003 can be smoother, the charging and discharging efficiency of the battery cell 003 can be higher, and the energy loss can be reduced.

[0217] In addition, by using the aforementioned winding core 001 , the pole pieces of at least one polarity of the battery cell 003 can be used as output ends at both ends, thereby improving the operability of the electrical connection of the battery cell 003 .

[0218] See also Figure 12 , Figure 12 FIG2 is a schematic diagram of the structure of a battery pack 004 provided in an embodiment of the present application. The embodiment of the present application provides a battery pack 004, which includes a battery box 041 and the aforementioned battery cells 003. The battery box 041 has a receiving cavity. Multiple battery cells 003 are disposed in the receiving cavity.

[0219] In this embodiment, by adopting the aforementioned battery cell 003 , the current transmission inside the battery pack 004 can be made smoother, the charging and discharging efficiency of the battery pack 004 can be higher, and the energy loss can be reduced.

[0220] See also Figure 13 , Figure 13005 is a schematic diagram of the structure of an electric device 005 provided in an embodiment of the present application. The embodiment of the present application provides an electric device 005, which includes the aforementioned battery cell 003 or battery pack 004, and the battery pack 004 or the battery cell 003 supplies power to the electric device.

[0221] It is understood that the electrical equipment 005 includes, but is not limited to, electric toys, electric tools, battery-powered vehicles, cars, ships, spacecraft, and the like. Electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft. Cars may include gasoline-powered cars, gas-powered cars, and new energy vehicles.

[0222] In this embodiment, by adopting the aforementioned battery pack 004 , the charging efficiency of the electric device 005 can be improved, the energy utilization rate of the electric device 005 can be improved, and the energy loss of the electric device 005 can be reduced.

[0223] The technical solutions and technical effects of the present application are described in detail below through specific embodiments. The following embodiments are only some embodiments of the present application and do not specifically limit the present application.

[0224] This example aims to investigate the effect of applying the winding core to a battery on battery performance.

[0225] The test contents of the embodiment are described as follows:

[0226] 1. Test related instructions

[0227] The following test method is a DCR test, that is, a Direct Current Resistance test.

[0228] The equipment used for the test is a power battery tester, and its model may be: CTE-8008-5V200A.

[0229] The test environment temperature is: 25±2℃.

[0230] The main operation process of the test is as follows:

[0231] First, take 1C=32.4A as the nominal capacity, 1 / 3C, i.e. 10.8Ah as the standard charge and discharge capacity, and the average value of the actual capacitance measured after 3 weeks of charge and discharge cycles as the calibration capacity C0, where:

[0232] C0=(∑I n *T n +∑I' n *T' n ) / 6,

[0233] In this formula: n is a natural number, and n∈(1,3);

[0234] I n is the nth charging current;

[0235] T n is the nth charging time;

[0236] I' n is the nth discharge current;

[0237] T' n is the nth discharge time.

[0238] Then charge the battery cell to 4.25V at a constant current and constant voltage of 1 / 3C, with a cut-off current of 0.05C; then adjust the state of charge of the battery cell to 50% SOC at a discharge current of 1 / 3C0, and let the battery cell stand for 1 hour.

[0239] Then, when the state of charge of the cell is 50% SOC, discharge it at a constant current of 2C0 for 30s, and record the voltage change difference δU before and after discharge. 放电 And the discharge current value I 放电 , and according to the formula: DCR 放电 =δU 放电 / I 放电 , get the battery charging DCR when the state of charge of the cell is 50% SOC;

[0240] At the same time, when the state of charge of the battery cell is 50% SOC, charge it at a constant current of 2C0 for 30s, and record the voltage change difference δU before and after charging. 充电 and charging current value I 充电 ; and according to the formula: DCR 充电 =δU 充电 / I 充电 , and the battery discharge DCR is obtained when the state of charge of the battery cell is 50% SOC.

[0241] 2. Test Results

[0242] The test results are all based on a battery cell with a core outer diameter A of 45.1mm, a core middle hole diameter of 5mm, a core height of 88.3±0.3mm, and an axial dimension of 4-5mm before the tab is bent.

[0243] 2.1 Setting up a control group

[0244] The control group is a battery cell with only positive and negative tabs on the first end in the related art. The test data is as follows:

[0245]

[0246] Table 1. Parameters and validation results of control groups 1 and 2

[0247] According to Table 1,

[0248] (1) In control group 1, the positive tab is set at the same end of the winding core, and the area of ​​the positive tab is 1002.4mm 2 , the negative ear area is 1067.6mm 2 When the state of charge of the battery cell is 50% SOC, the battery charging DCR is 3.72mΩ and the battery discharging DCR is 3.69mΩ.

[0249] (2) In control group 2, the positive tab is set at the same end of the winding core, and the positive tab area is 235mm 2 、Negative electrode ear area is 1067.6mm 2 When the state of charge of the battery cell is 50% SOC, the battery charging DCR is 4.18mΩ and the battery discharging DCR is 3.95mΩ.

[0250] 2.2 Based on the control group, the single variable method was used to change the parameter setting examples of the core. The parameter change tables and verification results of each example are shown in Tables 2 to 4.

[0251] 2.21 Under the premise that the rest of the structure is the same, a third pole tab is added at the second end of the winding core, and the third pole tab is the positive pole tab.

[0252] According to the formula: 3% A≤C≤30% A and: 65% A≤D≤80% A, the inner and outer diameter ranges of the third tab area formed by bending and stacking the positive tabs are: the inner diameter C of the positive tab: 1.353mm≤C≤13.53mm, the outer diameter D of the positive tab: 29.315mm≤D≤36.08mm. Among them, the area of ​​the negative tab remains unchanged, and the total area of ​​the positive tab is 1002.4mm. 2 and 999.9mm 2 Correspondingly, C is selected as 3mm and 13.5mm, and D is selected as 31.4mm and 34mm.

[0253] Based on the above content, the test data is as follows:

[0254]

[0255] Table 2. Parameters and verification results of the bottom-mounted positive electrode

[0256] Comparing Table 2 with Table 1, we can draw the following conclusions:

[0257] (1) The total area of ​​the positive tabs of Control Group 1 is equal to that of Example 1, both of which are 1002.4 mm 2The total area of the negative tab of the control group 1 and the total area of the negative tab of the example 1 are equal, both of which are 1067.6 mm 2 ; but the battery charging DCR of the control group 1 is 3.72 mΩ, and the battery discharging DCR is 3.69 mΩ; the battery charging DCR of the example 1 is 3.56 mΩ, and the battery discharging DCR is 3.68 mΩ. Thus, it can be known that the battery charging DCR of the example 1 is lower than the battery charging DCR of the control group 1, and the battery discharging DCR of the example 1 is lower than the battery discharging DCR of the control group 1.

[0258] Therefore, under the premise that the total areas of the positive and negative tabs are equal, respectively arranging the positive tabs at the first and second ends can reduce the battery charging DCR and help to reduce the battery discharging DCR, thereby improving the overcurrent capacity.

[0259] (2) The total area of the negative tab of the example 2 and the total area of the negative tab of the control group 1 are equal, both of which are 1067.6 mm 2 , and the total area of the positive tab of the example 2 is 999.9 mm 2 , which is lower than the total area of the positive tab of the control group 1: 1002.4 mm 2 ; but the battery charging DCR of the example 2 is 3.51 mΩ, which is lower than the battery charging DCR of the control group 1: 3.72 mΩ, and the battery discharging DCR of the example 2 is 3.64 mΩ, which is lower than the battery discharging DCR of the control group 1: 3.68 mΩ.

[0260] Therefore, under the premise that the total area of the negative tab is equal, respectively arranging the positive tabs at both ends of the winding core can reduce the battery charging DCR and help to reduce the battery discharging DCR, compared with arranging the positive tabs at only one end of the winding core, even if the total area of the positive tabs of the former is slightly lower than the total area of the positive tabs of the latter, thereby improving the overcurrent capacity.

[0261] (3) According to the comparison between the example 1 or the example 2 and the control group 2, it can be known that, under the premise that the areas of the positive and negative tabs arranged at the first end of the winding core are equal, arranging the positive tab at the second end of the winding core to increase the total area of the positive tab can reduce the battery charging DCR and help to reduce the battery discharging DCR, thereby improving the overcurrent capacity.

[0262] (4) According to the comparison between the example 1 and the example 2, it can be known that the greater the area of the positive tab arranged at the second end of the winding core, the greater the total area of the positive tab, and correspondingly, the smaller the battery charging DCR and the battery discharging DCR, thereby improving the overcurrent capacity.

[0263] 2.22 On the premise that the rest of the structure is the same, a third tab is added at the second end of the core, and the third tab is a positive tab. At the same time, the inner diameter of the third tab area is reduced so that the area of the positive tab increases in turn. The test data are as follows:

[0264]

[0265] Table 3. Parameters and verification results of the bottom provided with a positive tab

[0266] As can be seen from Table 3, on the premise that the areas of the positive and negative tabs at the first end are unchanged, as the area of the positive tab at the second end increases from 874.2 mm 2 to 938.5 mm 2 , 1067.6 mm 2 , the battery charging DCR decreases from 3.45 mΩ to 3.25 mΩ, 3.06 mΩ in turn, and correspondingly, the battery discharging DCR decreases from 3.35 mΩ to 3.30 mΩ, 3.15 mΩ in turn.

[0267] Therefore, by increasing the area of the positive tab at the second end, the total area of the positive tab is increased, so that the battery charging DCR is reduced, and the battery discharging DCR is also reduced, thereby improving the overcurrent capacity.

[0268] 2.23 On the basis of the foregoing embodiment, a fourth tab is added at the second end of the core, and the fourth tab is a negative tab. The area of the negative tab increases in turn.

[0269] According to the formula: 40% A≤C≤75% A and: 85% A≤D<100% A, the value range of the inner and outer diameters of the third tab area formed by the stacking of the positive tabs is: the inner diameter C of the positive tab: 18.4 mm≤C≤33.825 mm, and the outer diameter D of the positive tab: 38.353 mm≤D<45.1 mm. Among them, C is selected as: 33 mm, 28 mm, 25 mm, 22.5 mm in turn, and D is selected as: 45 mm, 42 mm, 40 mm, 38.5 mm.

[0270] According to the formula: 3% A≤J≤22% A and 25% A≤I≤35% A, the value range of the inner and outer diameters of the fourth tab area formed by the stacking of the negative tabs is: the inner diameter J of the negative tab: 1.353 mm≤J≤9.922 mm, and the outer diameter I of the negative tab: 11.275 mm≤I<15.785 mm. Among them, I is selected as: 12 mm, 13 mm, 14 mm and 15 mm in turn, and J is selected as: 8 mm. Correspondingly, the area of the negative tab at the second end is: 64.2 mm 2 , 82.4 mm 2 , 103.6 mm 2 , 126.3 mm 2 in turn.

[0271] Based on the above content, the test data is as follows:

[0272]

[0273] Table 4. Parameters and verification results of the bottom-mounted negative electrode

[0274] According to Table 4, the following conclusions can be drawn:

[0275] From the comparison of Example 6, Example 7, Example 8 and Example 9, it can be seen that under the premise that the areas of the positive and negative electrodes at the first end are equal and the areas of the positive tabs at the second end are equal, the area of ​​the negative tab at the second end is increased from 62.4 mm in Example 6 to 2 Increased to 82.4 mm in Example 7 2 , 103.6mm of Example 8 2 and 126.3 mm in Example 9 2 When the battery discharge DCR decreases from 3.32 mΩ in Example 6 to 3.27 mΩ in Example 7, 3.18 mΩ in Example 8, and 2.95 mΩ in Example 9; correspondingly, the battery charge DCR decreases from 3.43 mΩ in Example 6 to 3.39 mΩ in Example 7, 3.35 mΩ in Example 8, and 3.30 mΩ in Example 9.

[0276] Therefore, by increasing the area of ​​the negative tab at the second end, the total area of ​​the negative tab is increased, thereby reducing the battery discharge DCR and helping to reduce the battery charge DCR, thereby improving the overcurrent capability.

[0277] 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 second pole piece, and a diaphragm disposed between the first pole piece and the second pole piece, wherein the first pole piece and the second pole piece have opposite polarities, and along the axial direction of the winding core, the winding core body has a first end and a second end; a first pole lug, disposed at the first end and connected to the first pole piece; a second pole tab, disposed at the first end and connected to the second pole piece; The third electrode tab is provided at the second end, and the third electrode tab is connected to the first electrode piece or the second electrode piece.

2. The winding core according to claim 1, characterized in that The multiple layers of the third tabs are bent and stacked to form a third tab area, and the third tab area extends along the circumference of the winding core body into a closed or open ring shape.

3. The winding core according to claim 2, characterized in that Along the radial direction of the winding core, from the center of the winding core body to the outside, the second end is sequentially provided with a first central hollow lug area and the third tab area.

4. The winding core according to claim 3, characterized in that The inner diameter of the third tab region is C, and the outer diameter of the winding core body is A, satisfying: 3%A≤C≤30%A.

5. The winding core according to claim 2, characterized in that Along the radial direction of the winding core, from the center of the winding core body to the outside, the second end is sequentially provided with the third tab area and the first peripheral hollow tab area.

6. The winding core according to claim 5, characterized in that The outer diameter of the third tab region is D, and the outer diameter of the winding core body is A, satisfying the following: 65%A≤D≤80%A.

7. The winding core according to any one of claims 1 to 6, characterized in that: The third tab is connected to the first pole piece, and a projection plane perpendicular to the axis of the winding core body is used as a projection plane, and the axial direction of the winding core body is used as a projection direction. In the projection plane, the projection of the first tab before bending and the projection of the third tab before bending at least partially overlap; Alternatively, the third pole tab is connected to the second pole piece, with a plane perpendicular to the axis of the winding core body as the projection plane, and the axial direction of the winding core body as the projection direction. In the projection plane, the projection of the second pole tab before bending at least partially overlaps with the projection of the third pole tab before bending.

8. The winding core according to claim 1, characterized in that The winding core further includes a fourth pole tab, which is arranged at the second end of the winding core body. One of the third pole tab and the fourth pole tab is connected to the first pole piece, and the other is connected to the second pole piece.

9. The winding core according to claim 8, characterized in that The multiple layers of the third pole tabs are bent and stacked to form a third pole tab area, and the multiple layers of the fourth pole tabs are bent and stacked to form a fourth pole tab area. Along the radial direction of the core body, from the center of the core body to the outside, the second end is sequentially provided with the fourth pole tab area, the first middle ring hollow tab area and the third pole tab area. The fourth pole tab area and the third pole tab area respectively extend along the circumference of the core body into closed or open rings.

10. The winding core according to claim 8, characterized in that The multiple layers of the third pole tab are bent and stacked to form a third pole tab area, and the multiple layers of the fourth pole tab are bent and stacked to form a fourth pole tab area. Along the radial direction of the core body, from the center of the core body to the outside, the second end is sequentially provided with a third central hollow tab area, the fourth pole tab area and the third pole tab area. The fourth pole tab area and the third pole tab area respectively extend along the circumference of the core body into closed or open rings.

11. The winding core according to claim 10, characterized in that The inner diameter of the fourth tab region is J, and the outer diameter of the winding core body is A, satisfying: 3%A≤J≤22%A.

12. The winding core according to claim 8, characterized in that The multiple layers of the third pole tabs are bent and stacked to form a third pole tab area, and the multiple layers of the fourth pole tabs are bent and stacked to form a fourth pole tab area. Along the radial direction of the core body, from the center of the core body to the outside, the second end is sequentially provided with the fourth pole tab area, the third pole tab area and the third peripheral hollow tab area. The fourth pole tab area and the third pole tab area respectively extend along the circumference of the core body into closed or open rings.

13. The winding core according to claim 12, characterized in that The outer diameter of the third tab region is D, and the outer diameter of the winding core body is A, satisfying: 85%A≤D<100%A.

14. The winding core according to any one of claims 9 to 13, characterized in that: The outer diameter of the winding core body is A, the outer diameter of the fourth tab region is I, and the following conditions are met: 25%A≤I≤35%A; and / or the inner diameter of the third tab region is C, and the following conditions are met: 40%A≤C≤75%A.

15. The winding core according to any one of claims 8 to 13, characterized in that: The third electrode tab is connected to the first electrode piece.

16. The winding core according to claim 15, characterized in that A plane perpendicular to the axis of the winding core body is used as a projection plane, and the axial direction of the winding core body is used as a projection direction. In the projection plane, the projection of the first tab before bending partially overlaps with the projection of the third tab before bending.

17. The winding core according to any one of claims 8 to 13, characterized in that: The fourth pole tab is connected to the second pole piece.

18. The winding core according to claim 17, characterized in that Taking a plane perpendicular to the axis of the winding core body as a projection plane and the axial direction of the winding core body as a projection direction, in the projection plane, the projection of the second tab before bending at least partially overlaps with the projection of the fourth tab before bending.

19. The winding core according to claim 1, characterized in that The multiple layers of the first pole ears are bent and stacked to form a first pole ear area, and the multiple layers of the second pole ears are bent and stacked to form a second pole ear area. Along the radial direction of the core body, from the center of the core body to the outside, the first end is sequentially provided with a first pole ear area, a second middle ring hollow ear area and a second pole ear area. The first pole ear area and the second pole ear area respectively extend along the circumference of the core into closed or open rings.

20. The winding core according to claim 1, wherein The multiple layers of the first pole ears are bent and stacked to form a first pole ear area, and the multiple layers of the second pole ears are bent and stacked to form a second pole ear area. Along the radial direction of the core body, from the center of the core body to the outside, the first end is sequentially provided with a second central hollow ear area, the first pole ear area and the second pole ear area.

21. The winding core according to claim 20, characterized in that The inner diameter of the first tab area is M, and the outer diameter of the winding core body is A, satisfying: 3%A≤M≤22%A.

22. The winding core according to claim 1, wherein The multiple layers of the first pole ears are bent and stacked to form a first pole ear area, and the multiple layers of the second pole ears are bent and stacked to form a second pole ear area. Along the radial direction of the winding core body, from the center of the winding core body to the outside, the first end is sequentially provided with the first pole ear area, the second pole ear area and the second peripheral hollow ear area.

23. The winding core according to claim 22, characterized in that The outer diameter of the second tab region is E, and the outer diameter of the winding core body is A, satisfying: 85%A≤E<100%A.

24. The winding core according to any one of claims 19 to 23, characterized in that: The outer diameter of the winding core body is A, the outer diameter of the first tab area is G, and the following conditions are met: 35%A≤G≤50%A; and / or the inner diameter of the second tab area is F, and the following conditions are met: 60%A≤F≤75%A.

25. The winding core according to claim 24, characterized in that FG≥4mm.

26. The winding core according to any one of claims 19 to 23, characterized in that: The outer diameter of the second tab region is E, and the inner diameter of the second tab region is F, satisfying: EF≥4mm.

27. The winding core according to any one of claims 1-6 or 8-13, characterized in that The first electrode tab is a positive electrode tab, and the second electrode tab is a negative electrode tab.

28. A battery cell, characterized in that: include: A housing having a receiving cavity; And, the winding core according to any one of claims 1 to 27 is arranged in the accommodating cavity.

29. A battery pack, characterized in that: It comprises a box body and the battery cell as claimed in claim 28, wherein a plurality of the battery cells are installed in the box body.

30. An electrical device, characterized in that: It includes the battery cell as described in claim 28 or the battery pack as described in claim 29, and the battery pack or the battery cell supplies power to the electrical device.

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