Roll core, battery and electric equipment

Abstract

The utility model provides a roll core, a battery and electric equipment, the roll core comprises a pole piece assembly, and the pole piece assembly forms a plurality of stacked positive pole piece unit layers and negative pole piece unit layers; the roll core is provided with a roll core central surface, the pole piece assembly positioned on one side of the roll core central surface is a first section, and the pole piece assembly positioned on the other side of the roll core central surface is a second section; at least one part of the positive plate unit layer of the first section is provided with at least one positive tab; at least one part of the positive plate unit layer of the second section is provided with at least one positive tab; and / or at least one part of the negative plate unit layer of the first section is provided with at least one negative tab; and at least part of the negative plate unit layer of the second section is provided with at least one negative tab. In this way, the arrangement positions of the tabs are restrained, the arrangement number of the tabs can be restrained, and on the premise that the number of tab layers is effectively increased and the overcurrent capacity of the tab positions is guaranteed, the technology manufacturability and actual application can be considered, and the insufficient welding or over-welding risk of the tabs is avoided.

Description

Technical Field

[0001] This application relates to the field of lithium-ion battery technology, and in particular to a winding core, a battery including the winding core, and an electrical device including the battery. Background Technology

[0002] The increasing demand for fast charging and energy density in lithium-ion battery products presents significant challenges to temperature rise at the tabs and cell DCR (difference-to-charge ratio). Faster charging leads to higher temperature rise at the tabs, while higher energy density results in higher cell DCR and a corresponding decrease in fast charging capability. The current-carrying area at the tabs in the cell structure is one of the bottlenecks in improving fast charging temperature rise and DCR. Based on this, the industry is gradually increasing the number of tab layers in wound cores, aiming to place as many tabs as possible on a limited number of electrode layers. However, with an increased number of tab layers and non-standard placement, the constraints of increased total tab thickness, limited ultrasonic welding energy, and limited process windows can easily lead to risks of incomplete or excessive welding. Insufficient ultrasonic welding energy can cause incomplete welding of inner tabs and between the tabs and the adapter, while excessive ultrasonic welding energy can cause the tabs to melt through, reducing welding tensile strength and effective current-carrying area, thus increasing the challenge of ultrasonic welding and reducing manufacturability. Utility Model Content

[0003] In view of this, the purpose of this application is to provide a core, battery and electrical device that solves the problem that electrode welding is prone to cause poor soldering or over-soldering risks.

[0004] To achieve the above objectives, this application provides the following technical solution:

[0005] A winding core, comprising:

[0006] An electrode assembly includes at least one positive electrode and at least one negative electrode. The electrode assembly is continuously wound from the inner starting end of the core to the outer ending end of the core, forming multiple stacked positive electrode unit layers and negative electrode unit layers. The core has a core center plane perpendicular to the thickness direction of the core. The electrode assembly located on one side of the core center plane is a first segment, and the electrode assembly located on the other side of the core center plane is a second segment.

[0007] At least a portion of the positive electrode unit layers in the first segment are provided with at least one positive electrode tab; at least a portion of the positive electrode unit layers in the second segment are provided with at least one positive electrode tab;

[0008] And / or,

[0009] At least a portion of the negative electrode unit layers in the first segment are provided with at least one negative electrode tab; at least a portion of the negative electrode unit layers in the second segment are provided with at least one negative electrode tab.

[0010] Optionally, in the above-mentioned cores,

[0011] In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core,

[0012] The positive electrode unit layers from the 1st to the nth layer do not have positive electrode tabs, while the positive electrode unit layers from the (n+1)th to the bth layer each have one positive electrode tab; where 5≤n≤15, (n+1)≤b, b≤a, and a is the total number of positive electrode unit layers in the second segment.

[0013] And / or,

[0014] The negative electrode unit layers from layer 1 to layer n do not have negative electrode tabs, while the negative electrode unit layers from layer n+1 to layer d each have one negative electrode tab; where 5≤n≤15, (n+1)≤d, d≤c, and c is the total number of negative electrode unit layers in the second segment.

[0015] Optionally, in the above-mentioned cores,

[0016] In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core,

[0017] The positive electrode unit layers from layer 1 to layer n do not have positive electrode tabs. The positive electrode unit layer from layer n+1 has one positive electrode tab. In the positive electrode unit layers from layer n+2 to layer b, one positive electrode tab is provided in every y consecutive positive electrode unit layers after every x layers. Wherein, 5≤n≤15, (n+1)≤b, b≤a, 2≤x≤5, 2≤y≤5, and a is the total number of positive electrode unit layers in the second segment.

[0018] And / or,

[0019] The negative electrode unit layers from layer 1 to layer n do not have negative electrode tabs. The negative electrode unit layer from layer n+1 has one negative electrode tab. In the negative electrode unit layers from layer n+2 to layer d, one negative electrode tab is provided for every consecutive y negative electrode unit layers after every x layers. Wherein, 5≤n≤15, (n+1)≤d, d≤c, 2≤x≤5, 2≤y≤5, and c is the total number of negative electrode unit layers in the second segment.

[0020] Optionally, in the above-mentioned cores,

[0021] When a≤30, then (n+1)≤b≤a;

[0022] When 30 < a ≤ 40, then (n+1) < b ≤ a * 6 / 7;

[0023] When 40 < a ≤ 45, then (n+1) ≤ b ≤ a * 2 / 3;

[0024] When 45 < a ≤ 50, then (n+1) ≤ b ≤ a * 1 / 2;

[0025] When 50 < a ≤ 55, then (n+1) ≤ b ≤ a * 2 / 5;

[0026] When 55 < a ≤ 60, then (n+1) ≤ b ≤ a * 2 / 7;

[0027] When 60 < a ≤ 65, then (n+1) ≤ b ≤ a * 1 / 8;

[0028] When 65 < a ≤ 70, then (n+1) ≤ b ≤ a * 2 / 13;

[0029] When 70 < a ≤ 75, then (n+1) ≤ b ≤ a * 1 / 15;

[0030] And / or,

[0031] When c≤30, then (n+1)≤d≤c;

[0032] When 30 < c ≤ 40, then (n+1) < d ≤ c * 6 / 7;

[0033] When 40 < c ≤ 45, then (n+1) ≤ d ≤ c * 2 / 3;

[0034] When 45 < c ≤ 50, then (n+1) ≤ d ≤ c * 1 / 2;

[0035] When 50 < c ≤ 55, then (n+1) ≤ d ≤ c * 2 / 5;

[0036] When 55 < c ≤ 60, then (n+1) ≤ d ≤ c * 2 / 7;

[0037] When 60 < c ≤ 65, then (n+1) ≤ d ≤ c * 1 / 8;

[0038] When 65 < c ≤ 70, then (n+1) ≤ d ≤ c * 2 / 13;

[0039] When 70 < c ≤ 75, then (n+1) ≤ d ≤ c * 1 / 15;

[0040] And / or,

[0041] a < c.

[0042] Optionally, in the above-mentioned cores,

[0043] In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core,

[0044] In the positive electrode unit layers from the vth layer to the wth layer, at least a portion of the odd-numbered positive electrode unit layers are provided with a first positive electrode tab, and at least a portion of the even-numbered positive electrode unit layers are provided with a second positive electrode tab. On the center surface of the core, the orthographic projection of the first positive electrode tab and the orthographic projection of the second positive electrode tab do not overlap; wherein, 1≤v<a, v≤w≤a, and a is the total number of positive electrode unit layers in the second segment;

[0045] And / or,

[0046] In the negative electrode unit layers from the vth layer to the wth layer, at least a portion of the odd-numbered negative electrode unit layers are provided with a first negative electrode tab, and at least a portion of the even-numbered negative electrode unit layers are provided with a second negative electrode tab. On the center surface of the core, the orthographic projection of the first negative electrode tab and the orthographic projection of the second negative electrode tab do not overlap; wherein, 1≤v<a, v<w≤c, and c is the total number of negative electrode unit layers in the second segment.

[0047] Optionally, in the above-mentioned core, the number of odd-numbered layers from the v-th layer to the w-th layer is f1, and the number of even-numbered layers is f2; wherein:

[0048] When a ≤ 40, then 0 < f1 ≤ a / 2; 0 < f2 ≤ a / 2;

[0049] When 40 < a ≤ 45, then 0 < f1 ≤ a / 3 and 0 < f2 ≤ a / 3;

[0050] When 45 < a ≤ 50, then 0 < f1 ≤ a * 1 / 5 and 0 < f2 ≤ a * 1 / 5.

[0051] When 50 < a ≤ 55, then 0 < f1 ≤ a * 1 / 10 and 0 < f2 ≤ a * 1 / 10.

[0052] And / or,

[0053] When c≤40, then 0<f1≤a / 2; 0<f2≤a / 2;

[0054] When 40 < c ≤ 45, then 0 < f1 ≤ a / 3 and 0 < f2 ≤ a / 3;

[0055] When 45 < c ≤ 50, then 0 < f1 ≤ a * 1 / 5 and 0 < f2 ≤ a * 1 / 5.

[0056] When 50 < c ≤ 55, then 0 < f1 ≤ a * 1 / 10 and 0 < f2 ≤ a * 1 / 10.

[0057] Optionally, in the above-mentioned cores,

[0058] In the first segment, a portion of the positive electrode unit layer is provided with a fifth positive electrode tab, a portion of the positive electrode unit layer is provided with a third positive electrode tab, and a portion of the positive electrode unit layer is provided with a fourth positive electrode tab; along the direction from the side near the center surface of the core to the side away from the center surface of the core, the fifth positive electrode tab is located outside the third positive electrode tab and the fourth positive electrode tab, and the area of ​​the third positive electrode tab and the area of ​​the fourth positive electrode tab are both smaller than the area of ​​the fifth positive electrode tab;

[0059] And / or,

[0060] In the first segment, a portion of the positive electrode unit layer is provided with a fifth negative electrode tab, a portion of the negative electrode unit layer is provided with a third negative electrode tab, and a portion of the negative electrode unit layer is provided with a fourth negative electrode tab; along the direction from the side near the center surface of the core to the side away from the center surface of the core, the fifth negative electrode tab is located outside the third negative electrode tab and the fourth negative electrode tab, and the area of ​​the third negative electrode tab and the area of ​​the fourth negative electrode tab are both smaller than the area of ​​the fifth negative electrode tab.

[0061] Optionally, in the above-mentioned cores,

[0062] On the center surface of the core, the orthographic projections of the third positive electrode tab and the fourth positive electrode tab both at least partially overlap with the orthographic projection of the fifth positive electrode tab;

[0063] and / or

[0064] On the center surface of the core, the orthographic projections of the third negative electrode tab and the fourth negative electrode tab both at least partially overlap with the orthographic projection of the fifth negative electrode tab.

[0065] Optionally, in the above-mentioned cores,

[0066] On the center surface of the core, the orthographic projection of the third positive electrode tab and the orthographic projection of the fourth positive electrode tab do not overlap;

[0067] and / or

[0068] On the center surface of the core, the orthographic projections of the third negative electrode tab and the fourth negative electrode tab do not overlap.

[0069] Optionally, in the above-mentioned cores,

[0070] Along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core,

[0071] The third positive electrode tab is located in an odd-numbered layer, and the fourth positive electrode tab is located in an even-numbered layer;

[0072] and / or

[0073] The third negative electrode tab is located in an odd-numbered layer, and the fourth negative electrode tab is located in an even-numbered layer.

[0074] Optionally, in the above-mentioned cores,

[0075] On the center surface of the core, the orthographic projections of the first positive electrode tab and the third positive electrode tab at least partially overlap, and the orthographic projections of the second positive electrode tab and the fourth positive electrode tab at least partially overlap.

[0076] and / or

[0077] On the center surface of the core, the orthographic projections of the first negative electrode tab and the third negative electrode tab at least partially overlap, and the orthographic projections of the second negative electrode tab and the fourth negative electrode tab at least partially overlap.

[0078] Optionally, in the above-mentioned cores,

[0079] In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core,

[0080] A sixth positive electrode is provided on the outer portion of the positive electrode unit layer of the first and second positive electrode tabs. On the center surface of the core, the orthographic projection of the sixth positive electrode tab overlaps with the orthographic projection of the fifth positive electrode tab.

[0081] And / or,

[0082] A sixth negative electrode tab is provided on the outer portion of the negative electrode unit layer of the first and second negative electrode tabs. On the center surface of the core, the orthographic projection of the sixth negative electrode tab overlaps with the orthographic projection of the fifth negative electrode tab.

[0083] Optionally, in the above-mentioned cores,

[0084] On the center surface of the core, the orthographic projection of the sixth positive electrode tab completely overlaps with the orthographic projection of the fifth positive electrode tab.

[0085] and / or

[0086] On the center surface of the core, the orthographic projection of the sixth negative electrode tab completely overlaps with the orthographic projection of the fifth negative electrode tab.

[0087] Optionally, in the above-mentioned core, along the thickness direction of the core, from one side of the core to the other side of the core,

[0088] The height of each of the positive electrode tabs on each of the aforementioned positive electrode unit layers increases sequentially, and / or

[0089] The height of each negative electrode tab on each negative electrode unit layer increases sequentially.

[0090] A battery comprising a winding core as described above.

[0091] An electrical device comprising a battery as described above.

[0092] In the winding core, battery, and electrical equipment of this application, the electrode assembly is divided into a first segment located on one side of the center surface of the winding core and a second segment located on the other side of the center surface of the winding core. By setting tabs in at least a portion of the electrode unit layers in the first segment and setting tabs in at least a portion of the electrode unit layers in the second segment, not only is the setting position of the tabs constrained, but also the number of tabs can be constrained. While effectively increasing the number of tab layers to ensure the current carrying capacity of the tab position, it can also take into account the manufacturability of the process, make it practically applicable, and avoid the risk of tab poor soldering or over-soldering. Attached Figure Description

[0093] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0094] Figure 1 This is a schematic diagram of the structure of the core according to an embodiment of this application;

[0095] Figure 2 for Figure 1 A cross-sectional view of the negative electrode ear side;

[0096] Figure 3 for Figure 1 A cross-sectional view of the positive electrode ear side;

[0097] Figure 4 This is a schematic diagram of the structure of the core according to another embodiment of this application;

[0098] Figure 5 for Figure 4 A cross-sectional view of the negative electrode ear side;

[0099] Figure 6 for Figure 4 A cross-sectional view of the positive electrode ear side;

[0100] Figure 7 This is a schematic diagram of the structure of the core according to another embodiment of this application;

[0101] Figure 8 for Figure 7 A cross-sectional view of the negative electrode ear side;

[0102] Figure 9 for Figure 7 A cross-sectional view of the positive electrode ear side;

[0103] Figure 10 This is a schematic diagram of the structure of the core according to another embodiment of this application;

[0104] Figure 11 for Figure 10 A cross-sectional view of the negative electrode ear side;

[0105] Figure 12 for Figure 10 A cross-sectional view of the positive electrode ear side;

[0106] Figure 13 This is a schematic diagram of the core structure according to another embodiment;

[0107] Figure 14 for Figure 13 A cross-sectional view of the negative electrode ear side;

[0108] Figure 15 for Figure 13 A cross-sectional view of the positive electrode ear side;

[0109] Figure 16 This is a schematic diagram of the core structure according to another embodiment;

[0110] Figure 17 for Figure 16 A cross-sectional view of the negative electrode ear side;

[0111] Figure 18 for Figure 16 A cross-sectional view of the positive electrode ear side;

[0112] Figure 19 This is a schematic diagram of the core structure according to another embodiment;

[0113] Figure 20 for Figure 19 A cross-sectional view of the negative electrode ear side;

[0114] Figure 21 for Figure 19 Cross-sectional view of the positive electrode ear side.

[0115] superior Figures 1-21 middle:

[0116] 1. Positive electrode unit layer; 2. Negative electrode unit layer; 3. First section; 4. Second section; 5. Positive electrode tab; 6. Negative electrode tab;

[0117] 51. First positive electrode ear; 52. Second positive electrode ear; 53. Third positive electrode ear; 54. Fourth positive electrode ear; 55. Fifth positive electrode ear; 56. Sixth positive electrode ear.

[0118] 61. First negative electrode ear; 62. Second negative electrode ear; 63. Third negative electrode ear; 64. Fourth negative electrode ear; 65. Fifth negative electrode ear; 66. Sixth negative electrode ear. Detailed Implementation

[0119] This application provides a core, battery, and electrical device, which divides the electrode assembly into a first segment located on one side of the core's center plane and a second segment located on the other side of the core's center plane. By setting tabs on a small portion of the electrode unit layers in the first segment and setting tabs on at least a portion of the electrode unit layers in the second segment, not only are the positions of the tabs constrained, but the number of tabs can also be constrained. While effectively increasing the number of tab layers to ensure the current carrying capacity of the tab positions, it can also take into account manufacturability, making it practically applicable and avoiding the risk of tab poor soldering or over-soldering.

[0120] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0121] like Figures 1-21 As shown in the embodiment of this application, a core is provided. The core includes an electrode assembly, which includes at least one positive electrode and at least one negative electrode, as well as a separator located between the positive and negative electrode. The electrode assembly is continuously wound from the inner starting end of the core to the outer ending end of the core, forming multiple stacked positive electrode unit layers 1 and negative electrode unit layers 2. The core has a core center surface perpendicular to the core thickness direction. The electrode assembly located on one side of the core center surface is a first segment 3, and the electrode assembly located on the other side of the core center surface is a second segment 4. At least a portion of the positive electrode unit layers 1 of the first segment 3 are provided with at least one positive electrode tab 5; at least a portion of the positive electrode unit layers 1 of the second segment 4 are provided with at least one positive electrode tab 5. At least a portion of the negative electrode unit layers 2 of the first segment 3 are provided with at least one negative electrode tab 6; at least a portion of the negative electrode unit layers 2 of the second segment 4 are provided with at least one negative electrode tab 6.

[0122] Optionally, each layer of the positive electrode unit layer 1 in the first segment 3 is provided with a positive electrode tab 5, and each layer of the negative electrode unit layer 2 in the first segment 3 is provided with a negative electrode tab 6. In the second segment 4, at least some layers of the positive electrode unit layer 1 are selectively selected, and each layer of these selected layers is provided with a positive electrode tab 5; in the second segment 4, at least some layers of the negative electrode unit layer 2 are selectively selected, and each layer of these selected layers is provided with a negative electrode tab 6.

[0123] It should be noted that the positive electrode sheet, negative electrode sheet, and separator are stacked and wound to form a core. The positive electrode sheet includes a positive current collector and a layer of positive active material disposed on the positive current collector; a positive electrode tab 5 integrally connected to the positive current collector is obtained through die-cutting. The negative electrode sheet includes a negative current collector and a layer of negative active material coated on the negative current collector; a negative electrode tab 6 integrally connected to the negative current collector is obtained through die-cutting. Along the length direction of the positive electrode sheet, the length of each positive electrode sheet unit layer 1 gradually increases, so that after winding, each positive electrode sheet unit layer 1 is sequentially stacked and wound along the direction from the side closer to the center surface of the core to the side farther from the center surface of the core; along the length direction of the positive electrode sheet, the spacing between each positive electrode tab 5 gradually increases. Along the length direction of the negative electrode sheet, the length of each negative electrode sheet unit layer 2 gradually increases, so that after winding, each negative electrode sheet unit layer 2 is sequentially stacked and wound along the direction from the side closer to the center surface of the core to the side farther from the center surface of the core; along the length direction of the negative electrode sheet, the spacing between each negative electrode tab 6 gradually increases. The core is divided into two halves arranged side by side along its thickness direction. The first segment 3 is located in one half of the core, and the second segment 4 is located in the other half of the core. One of the first segment 3 and the second segment 4 is the upper half of the electrode assembly, and the other segment is the lower half of the electrode assembly; preferably, the first segment 3 is the lower half of the electrode assembly, and the second segment 4 is the upper half of the electrode assembly.

[0124] It should be further noted that the core thickness direction is shown in the appendix. Figure 1 The direction indicated by the middle arrow; the location of the center line of the core is attached. Figure 1 The location of the dotted line; also refer to the appendix for the direction along the side closer to the center surface of the core to the side farther away from the center surface of the core. Figure 1 The direction indicated by the middle arrow.

[0125] By providing positive tabs 5 on all positive electrode unit layers 1 in the first segment 3, and selectively providing positive tabs 5 on at least some layers of all positive electrode unit layers 1 in the second segment 4, not only are the placement positions of the positive tabs 5 constrained, but also their number. This effectively increases the number of positive tab layers to ensure the current carrying capacity of the positive tab positions while also considering manufacturability and practical applicability, avoiding the risk of incomplete or over-soldering when welding the positive tabs 5 to the positive electrode adapter. Similarly, by providing negative tabs 6 on all negative electrode unit layers 2 in the first segment 3, and selectively providing negative tabs 6 on at least some layers of all negative electrode unit layers 2 in the second segment 4, not only are the placement positions of the negative tabs 6 constrained, but also their number. This effectively increases the number of negative tab layers to ensure the current carrying capacity of the negative tab positions while also considering manufacturability and practical applicability, avoiding the risk of incomplete or over-soldering when welding the negative tabs 6 to the negative electrode adapter.

[0126] Please see the appendix Figure 1-3In some embodiments of this application, the positive electrode tabs 5 are configured by selectively selecting a portion of the positive electrode unit layers 1 from all the positive electrode unit layers 1 in the second segment 4 according to the positive electrode tab arrangement rule; specifically:

[0127] In the second section 4, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, the first to the nth positive electrode unit layer 1 do not have positive electrode tabs 5, while the (n+1)th to the bth positive electrode unit layer 1 each have one positive electrode tab 5; where 5≤n≤15, (n+1)≤b, b≤a, and a is the total number of positive electrode unit layer 1 layers in the second section 4. n can be any one of 5, 8, 10, 13, 15, etc. On the center surface of the core, the orthographic projections of multiple positive electrode tabs 5 overlap.

[0128] As mentioned above, in the second section 4, the positive electrode tab 5 is no longer provided on the multi-layer positive electrode unit layer 1 closest to the center surface of the core. Instead, a positive electrode tab 5 is provided on each of the several consecutive positive electrode unit layers 1 that are far from the center surface of the core. Since the length of the positive electrode unit layer 1 increases the further away from the center surface of the core, adding a positive electrode tab 5 to the positive electrode unit layer 1 that is far away from the center surface of the core is better for shortening the electron path.

[0129] Please see the appendix Figure 1-3 In some embodiments, the negative electrode tabs 6 are set by selectively selecting a portion of the negative electrode unit layers 2 from all the negative electrode unit layers 2 in the second segment 4 according to the negative electrode tab arrangement rule; specifically:

[0130] In the second section 4, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, the first to the nth negative electrode unit layer 2 do not have negative electrode tabs 6, while the (n+1)th to the bth negative electrode unit layer 2 each have one negative electrode tab 6; where 5≤n≤15, (n+1)≤d, d≤c, and c is the total number of negative electrode unit layer layers 2 in the second section 4. n can be any one of 5, 8, 10, 13, 15, etc. On the center surface of the core, the orthographic projections of multiple negative electrode tabs 6 overlap.

[0131] As mentioned above, in the second section 4, the negative electrode tab 6 is no longer provided on the multi-layer negative electrode unit layer 2 closest to the center surface of the core. Instead, a negative electrode tab 6 is provided on each of the several consecutive negative electrode unit layers 2 far from the center surface of the core. Since the length of the negative electrode unit layer 2 increases the further away from the center surface of the core, adding negative electrode tabs 6 to the negative electrode unit layer 2 far from the center surface of the core is better for shortening the electron path.

[0132] Please see the appendix Figure 4-6 In some embodiments of this application, the positive electrode tabs 5 are configured by selectively selecting a portion of the positive electrode unit layers 1 from all the positive electrode unit layers 1 in the second segment 4 according to the second positive electrode tab arrangement rule 2; specifically:

[0133] In the second section 4, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, the first to the nth positive electrode unit layer 1 do not have positive electrode tabs 5. The (n+1)th positive electrode unit layer 1 has one positive electrode tab 5. In the (n+2)th to the bth positive electrode unit layers 1, every x layers of positive electrode unit layers 1 followed by y consecutive positive electrode unit layers 1 have one positive electrode tab 5. Wherein, 5≤n≤15, (n+1)≤b, b≤a, 2≤x≤5, 2≤y≤5, and a is the total number of positive electrode unit layer layers 1 in the second section 4. n can be any one of 5, 8, 10, 13, 15, etc. x can be any one of 2, 3, 4, 5. y can be any one of 2, 3, 4, 5. On the center surface of the core, the orthographic projections of multiple positive electrode tabs 5 overlap.

[0134] As mentioned above, in the second section 4, the positive electrode tabs 5 are no longer provided on the multi-layer positive electrode unit layer 1 closest to the center surface of the core. Instead, a positive electrode tab 5 is provided on each consecutive specific layer of positive electrode unit layer 1 after a certain interval in several consecutive layers away from the center surface of the core. That is, the positive electrode tabs 5 are spaced out. Since the length of the positive electrode unit layer 1 is longer the further away from the center surface of the core, adding positive electrode tabs 5 on the positive electrode unit layer 1 away from the center surface of the core is better for shortening the electron path. Furthermore, by spaced out the positive electrode tabs 5, while ensuring the total number of positive electrode tab layers and significantly shortening the electron path, it also facilitates the solderability of the positive electrode tabs 5, avoids excessive total thickness of all the stacked positive electrode tabs 5, avoids soldering interference, and meets the requirements of process manufacturability.

[0135] Please see the appendix Figure 4-6 In some embodiments, the negative electrode tabs 6 are set by selectively selecting a portion of the negative electrode unit layers 2 in the second segment 4 according to the negative electrode tab arrangement rule 2; specifically:

[0136] In the second section 4, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, the first to the nth negative electrode unit layer 2 do not have negative electrode tabs 6. The (n+1)th negative electrode unit layer 2 has one negative electrode tab 6. In the (n+2)th to the dth negative electrode unit layers, every x layers of negative electrode unit layer 2 followed by y consecutive negative electrode unit layer layers 2 have one negative electrode tab 6. Wherein, 5≤n≤15, (n+1)≤d, d≤c, 2≤x≤5, 2≤y≤5, and c is the total number of negative electrode unit layer layers 2 in the second section 4. n can be any one of 5, 8, 10, 13, 15, etc. x can be any one of 2, 3, 4, 5. y can be any one of 2, 3, 4, 5. On the center surface of the core, the orthographic projections of multiple negative electrode tabs 6 overlap.

[0137] As mentioned above, in the second section 4, negative electrode tabs 6 are no longer provided on the multi-layer negative electrode unit layer 2 closest to the center surface of the core. Instead, a negative electrode tab 6 is provided on each consecutive specific layer of negative electrode unit layer 2 after a certain interval in several consecutive layers away from the center surface of the core. That is, the negative electrode tabs 6 are spaced out. Since the length of the negative electrode unit layer 2 increases as it moves further away from the center surface of the core, adding negative electrode tabs 6 on the negative electrode unit layer 2 away from the center surface of the core is better for shortening the electronic path. Furthermore, by spaced out the negative electrode tabs 6, while ensuring the total number of negative electrode tab layers 6 and significantly shortening the electronic path, it also facilitates the solderability of the negative electrode tabs 6, avoids excessive total thickness of all the stacked negative electrode tabs 6, avoids soldering interference, and meets the requirements of process manufacturability.

[0138] In some embodiments of this application, when the positive electrode tab 5 is arranged according to positive electrode tab arrangement rule one or positive electrode tab arrangement rule two:

[0139] When a≤30, then (n+1)≤b≤a;

[0140] When 30 < a ≤ 40, then (n+1) < b ≤ a * 6 / 7;

[0141] When 40 < a ≤ 45, then (n+1) ≤ b ≤ a * 2 / 3;

[0142] When 45 < a ≤ 50, then (n+1) ≤ b ≤ a * 1 / 2;

[0143] When 50 < a ≤ 55, then (n+1) ≤ b ≤ a * 2 / 5;

[0144] When 55 < a ≤ 60, then (n+1) ≤ b ≤ a * 2 / 7;

[0145] When 60 < a ≤ 65, then (n+1) ≤ b ≤ a * 1 / 8;

[0146] When 65 < a ≤ 70, then (n+1) ≤ b ≤ a * 1 / 13;

[0147] When 70 < a ≤ 75, then (n+1) ≤ b ≤ a * 1 / 30.

[0148] As shown above, the number of positive electrode unit layer 1 of positive electrode tab 5 can be adjusted according to the total number of positive electrode unit layer 1 to suit various types and specifications of cores, making it highly flexible and adaptable. It specifically constrains the setting position and number of positive electrode tabs 5, effectively increasing the number of positive electrode tab layers to ensure the current carrying capacity of the positive electrode tab position, while also taking into account the manufacturability of the process, making it practically applicable and avoiding the risk of poor soldering or over-soldering of positive electrode tab 5.

[0149] In some embodiments of this application, when the negative electrode tab 6 is arranged according to negative electrode tab arrangement rule one or negative electrode tab arrangement rule two:

[0150] When c≤30, then (n+1)≤d≤c;

[0151] When 30 < c ≤ 40, then (n+1) < d ≤ c * 6 / 7;

[0152] When 40 < c ≤ 45, then (n+1) ≤ d ≤ c * 2 / 3;

[0153] When 45 < c ≤ 50, then (n+1) ≤ d ≤ c * 1 / 2;

[0154] When 50 < c ≤ 55, then (n+1) ≤ d ≤ c * 2 / 5;

[0155] When 55 < c ≤ 60, then (n+1) ≤ d ≤ c * 2 / 7;

[0156] When 60 < c ≤ 65, then (n+1) ≤ d ≤ c * 1 / 8;

[0157] When 65 < c ≤ 70, then (n+1) ≤ d ≤ c * 1 / 13;

[0158] When 70 < c ≤ 75, then (n+1) ≤ d ≤ c * 1 / 30.

[0159] As shown above, the number of negative electrode unit layer 2 can be adjusted according to the total number of negative electrode unit layer 2 to suit various types and specifications of winding cores, making it highly flexible and adaptable. It specifically constrains the setting position and number of negative electrode tabs 6, effectively increasing the number of negative electrode tab layers to ensure the current carrying capacity of the negative electrode tab position, while also taking into account the manufacturability of the process, making it practically applicable and avoiding the risk of poor soldering or over-soldering of negative electrode tabs 6.

[0160] Furthermore, the total number of layers a of positive electrode unit layer 1 is different from the total number of layers c of negative electrode unit layer 2. Generally, the core ends with the negative electrode, so the total number of layers a of positive electrode unit layer 1 is less than the total number of layers c of negative electrode unit layer 2. Optionally, the difference between the number of layers a and c in the first segment 3 is 1, and the difference between the number of layers a and c in the second segment 4 is 1.

[0161] Please see the appendix Figure 7-12 In some embodiments of this application, the positive electrode tabs 5 are configured by selectively selecting a portion of the positive electrode unit layers 1 from all the positive electrode unit layers 1 in the second segment 4 according to the positive electrode tab arrangement rule 3; specifically:

[0162] In the second segment 4, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, in the v-th to w-th positive electrode unit layers 1, at least a portion of the odd-numbered positive electrode unit layers 1 are provided with first positive electrode tabs 51, and at least a portion of the even-numbered positive electrode unit layers 1 are provided with second positive electrode tabs 52. On the center surface of the core, the orthographic projections of the first positive electrode tab 51 and the second positive electrode tab 52 do not overlap; where 1≤v<a, v≤w≤a, and a is the total number of positive electrode unit layers 1 in the second segment 4. Optionally, v=1, w=a.

[0163] As described above, in the second section 4, in each positive electrode unit layer 1, the first positive electrode tab 51 located in the odd-numbered layer and the second positive electrode tab 52 located in the even-numbered layer are arranged alternately and staggered. As described above, this maximizes the total number of positive electrode tabs 5 in the second section 4 (i.e., the sum of the number of the first positive electrode tabs 51 and the second positive electrode tabs 52), thereby improving the current carrying capacity of the positive electrode tabs. Furthermore, by alternating and staggering the arrangement of the first positive electrode tab 51 located in the odd-numbered layer and the second positive electrode tab 52 located in the even-numbered layer, the positive electrode tabs 5 are arranged in two columns, avoiding the excessive total thickness of the positive electrode tabs 5 caused by single-layer stacking. This ensures that the welding positions of the positive electrode tabs 5 on adjacent positive electrode unit layers 1 are staggered with those of the positive electrode adapter, reliably avoiding welding interference, facilitating the weldability of the positive electrode tabs 5, and meeting the requirements of process manufacturability.

[0164] Please see the appendix Figure 7-12 In some embodiments of this application, the negative electrode tabs 6 are configured by selectively selecting a portion of the negative electrode unit layers 2 from all the negative electrode unit layers 2 in the second segment 4 according to the negative electrode tab arrangement rule 3; specifically:

[0165] In the second segment 4, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, in the v-th to w-th negative electrode unit layers 2, at least some of the odd-numbered negative electrode unit layers 2 are provided with first negative electrode tabs 61, and at least some of the even-numbered negative electrode unit layers 2 are provided with second negative electrode tabs 62. On the center surface of the core, the orthographic projections of the first negative electrode tab 61 and the second negative electrode tab 62 do not overlap; where 1≤v<a, v<w≤c, and c is the total number of negative electrode unit layer layers 2 in the second segment 4. Optionally, v=1, w=a.

[0166] As described above, in the second section 4, in each negative electrode unit layer 2, the first negative electrode tab 61 located in the odd-numbered layer and the second negative electrode tab 62 located in the even-numbered layer are arranged alternately and staggered. As described above, this maximizes the total number of negative electrode tabs 6 in the second section 4 (i.e., the sum of the number of the first negative electrode tabs 61 and the second negative electrode tabs 62), improving the current carrying capacity of the negative electrode tabs. Furthermore, by alternating and staggering the first negative electrode tab 61 located in the odd-numbered layer and the second negative electrode tab 62 located in the even-numbered layer, the negative electrode tabs 6 are arranged in two columns, avoiding the excessive total thickness of the negative electrode tabs 6 caused by single-layer stacking. This ensures that the welding positions of the negative electrode tabs 6 on adjacent negative electrode unit layers 2 are staggered, reliably avoiding welding interference, facilitating the weldability of the negative electrode tabs 6, and meeting the requirements of process manufacturability.

[0167] In some embodiments of this application, when the positive electrode 5 is arranged according to the positive electrode arrangement rule three:

[0168] When a ≤ 40, then 0 < f1 ≤ a / 2; 0 < f2 ≤ a / 2;

[0169] When 40 < a ≤ 45, then 0 < f1 ≤ a / 3 and 0 < f2 ≤ a / 3;

[0170] When 45 < a ≤ 50, then 0 < f1 ≤ a * 1 / 5 and 0 < f2 ≤ a * 1 / 5.

[0171] When 50 < a ≤ 55, then 0 < f1 ≤ a * 1 / 10 and 0 < f2 ≤ a * 1 / 10.

[0172] As shown above, the total number of odd-numbered layers of the first positive electrode tab 51 and the total number of even-numbered layers of the second positive electrode tab 52 can be adjusted according to the total number of layers of the positive electrode unit layer 1, so as to be suitable for various types and specifications of cores, with strong flexibility and applicability.

[0173] In some embodiments, when the negative electrode tab 6 is arranged according to negative electrode tab arrangement rule three:

[0174] When c≤40, then 0<f1≤a / 2; 0<f2≤a / 2;

[0175] When 40 < c ≤ 45, then 0 < f1 ≤ a / 3 and 0 < f2 ≤ a / 3;

[0176] When 45 < c ≤ 50, then 0 < f1 ≤ a * 1 / 5 and 0 < f2 ≤ a * 1 / 5.

[0177] When 50 < c ≤ 55, then 0 < f1 ≤ a * 1 / 10 and 0 < f2 ≤ a * 1 / 10.

[0178] As shown above, the total number of odd-numbered layers of the first negative electrode tab 61 and the total number of even-numbered layers of the second negative electrode tab 62 can be adjusted according to the total number of layers of the negative electrode unit layer 2, so as to be suitable for various types and specifications of cores, with strong flexibility and applicability.

[0179] Furthermore, when the positive electrode tab 5 is arranged according to the positive electrode tab arrangement rule three, the center distance between the first positive electrode tab 51 and the second positive electrode tab 52 is (j+5)±4mm; j+j+5=i; where i is the width of the positive electrode tab 5 set in the first segment 3, and j is the width of the positive electrode tab 5 set in the second segment 4.

[0180] As described above, the center distance between the first positive electrode tab 51 and the second positive electrode tab 52 can be controlled within a reasonable range, avoiding the risk of overlap between the first positive electrode tab 51 and the second positive electrode tab 52 if the center distance between the two is too small, and avoiding the risk of insufficient space in the width direction of the core (the width direction of the core is also the length direction of the positive electrode sheet) and the first positive electrode tab 51 and / or the second positive electrode tab 52 covering the liquid injection hole and the explosion-proof valve if the center distance between the two is too large.

[0181] Furthermore, when the negative electrode tab 6 is arranged according to the third negative electrode tab arrangement rule, the center distance between the first negative electrode tab 61 and the second negative electrode tab 62 is (L+5)±4mm; L+L+5=k; where L is the width of the negative electrode tab 6 set in the first segment 3, and k is the width of the negative electrode tab 6 set in the second segment 4.

[0182] As described above, the center distance between the first negative electrode tab 61 and the second negative electrode tab 62 can be controlled within a reasonable range, avoiding the risk of overlap between the first negative electrode tab 61 and the second negative electrode tab 62 if the center distance between them is too small, and avoiding the risk of insufficient space in the width direction of the core (the width direction of the core is the length direction of the negative electrode sheet) and the first negative electrode tab 61 and / or the second negative electrode tab 62 covering the injection hole and the explosion-proof valve if the center distance between them is too large.

[0183] Please see the appendix Figure 16-18 In some parallel embodiments, positive electrode tabs 5 can also be arranged on the positive electrode unit layer 1 of the second segment 4 according to the positive electrode tab arrangement rule four, that is:

[0184] Along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, each positive electrode unit layer 1 from the 1st layer to the pth layer is provided with a positive electrode tab 5, and each positive electrode unit layer 1 from the p+1th layer to the ath layer is not provided with a positive electrode tab; where p < a, and a is the total number of positive electrode unit layer 1 layers.

[0185] Please see the appendix Figure 16-18 Furthermore, negative electrode tabs 6 can also be arranged in the negative electrode unit layer 2 of the second section 4 according to the negative electrode tab arrangement rule four, that is:

[0186] Along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, each negative electrode unit layer 2 from the 1st layer to the pth layer is provided with a negative electrode tab 6, and each negative electrode unit layer 2 from the p+1th layer to the cth layer is not provided with a negative electrode tab c; where p < c, and c is the total number of negative electrode unit layer 2.

[0187] Please see the appendix Figure 19-21 In some parallel embodiments, positive electrode tabs 5 can also be arranged on the positive electrode unit layer 1 of the second segment 4 according to the positive electrode tab arrangement rule five, that is:

[0188] Along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, each positive electrode unit layer 1 from the 1st layer to the qth layer does not have a positive electrode tab 5, and each positive electrode unit layer 1 from the q+1th layer to the ath layer has a positive electrode tab 5; where 1 < q < a, and a is the total number of positive electrode unit layer 1.

[0189] Please see the appendix Figure 19-21 Furthermore, negative electrode tabs 6 can be arranged in the negative electrode unit layer 2 of the second section 4 according to the negative electrode tab arrangement rule five, that is:

[0190] Along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, each positive electrode unit layer 1 from layer 1 to layer q does not have a negative electrode tab 6, and each positive electrode unit layer 1 from layer q+1 to layer c has a negative electrode tab 6; where 1 < q < c, and c is the total number of negative electrode unit layers 2.

[0191] Please see the appendix Figure 13-15 In some embodiments of this application, the positive electrode tab 5 includes a third positive electrode tab 53, a fourth positive electrode tab 54, and a fifth positive electrode tab 55. In the first segment 3, a portion of the positive electrode unit layer 1 is provided with the fifth positive electrode tab 55, a portion of the positive electrode unit layer 1 is provided with the third positive electrode tab 53, and a portion of the positive electrode unit layer 1 is provided with the fourth positive electrode tab 54. Along the direction from the side near the center surface of the core to the side away from the center surface of the core, the fifth positive electrode tab 55 is located outside the third positive electrode tab 53 and the fourth positive electrode tab 54, and the area of ​​the third positive electrode tab 53 and the area of ​​the fourth positive electrode tab 54 are both smaller than the area of ​​the fifth positive electrode tab 55.

[0192] Optionally, in the first segment 3, among the positive electrode unit layers 1 from the 1st to the z1th layer, the odd-numbered positive electrode unit layers 1 are provided with a third positive electrode tab 53, the even-numbered positive electrode unit layers 1 are provided with a fourth positive electrode tab 54, and the z1th to the ath positive electrode unit layers 1 are provided with a fifth positive electrode tab 55. The third positive electrode tab 53 and the fourth positive electrode tab 54 can be arranged sequentially in a aligned stacked manner, or they can be arranged alternately and staggered.

[0193] As mentioned above, in the first paragraph 3, since the length of the positive electrode unit layer 1 closer to the center surface of the core is shorter, the space available for die-cutting the positive electrode tabs is more limited, and the required current flow is smaller. Therefore, setting the tabs of the several positive electrode unit layers 1 near the center surface of the core as small-area third positive electrode tabs 53 and fourth positive electrode tabs 54 not only facilitates the processing of the positive electrode tabs but also meets the current flow requirements of the positive electrode unit layers 1 located in the inner ring of the core. Conversely, since the length of the positive electrode unit layer 1 further away from the center surface of the core is longer, the space available for die-cutting the positive electrode tabs is larger, and the required current flow is also greater. Therefore, setting the tabs of the several positive electrode unit layers 1 further away from the center surface of the core as large-area fifth positive electrode tabs 55 ensures the current flow capacity of the positive electrode tabs while maintaining solderability.

[0194] Please see the appendix Figure 13-15 In some embodiments of this application, the negative electrode tab 6 includes a third negative electrode tab 63, a fourth negative electrode tab 64, and a fifth negative electrode tab 65. In the first segment 3, a portion of the negative electrode unit layer 2 is provided with the fifth negative electrode tab 65, a portion of the negative electrode unit layer 2 is provided with the third negative electrode tab 63, and a portion of the negative electrode unit layer 2 is provided with the fourth negative electrode tab 64. Along the direction from the side near the center surface of the core to the side away from the center surface of the core, the fifth negative electrode tab 65 is located outside the third negative electrode tab 63 and the fourth negative electrode tab 64, and the area of ​​the third negative electrode tab 63 and the area of ​​the fourth negative electrode tab 64 are both smaller than the area of ​​the fifth negative electrode tab 65.

[0195] Optionally, in the first segment 3, among the negative electrode unit layers 2 from the 1st to the z2th layer, the odd-numbered negative electrode unit layers 2 are provided with a third negative electrode tab 63, the even-numbered negative electrode unit layers 2 are provided with a fourth negative electrode tab 64, and the z2th to cth negative electrode unit layers 2 are provided with a fifth negative electrode tab 65. The third negative electrode tab 63 and the fourth negative electrode tab 64 can be arranged sequentially in a positive stack, or they can be arranged alternately and staggered.

[0196] As mentioned above, in the first section 3, since the negative electrode unit layer 2 closer to the center surface of the core is shorter, the space available for die-cutting negative electrode tabs is more limited, and the required current flow is smaller. Therefore, setting the negative electrode tabs of the several negative electrode unit layers 2 near the center surface of the core as small-area third negative electrode tabs 63 and fourth negative electrode tabs 64 not only facilitates the processing of the negative electrode tabs but also meets the current flow requirements of the negative electrode unit layers 2 located in the inner ring of the core. Conversely, since the negative electrode unit layer 2 further away from the center surface of the core is longer, the space available for die-cutting negative electrode tabs is larger, and the required current flow is also greater. Setting the negative electrode tabs of the several negative electrode unit layers 2 further away from the center surface of the core as large-area fifth negative electrode tabs 65 ensures the current flow capacity of the negative electrode tabs while maintaining weldability.

[0197] In some embodiments of this application, on the center surface of the core, the orthographic projections of the third positive electrode tab 53 and the fourth positive electrode tab 54 at least partially overlap with the orthographic projection of the fifth positive electrode tab 55. Optionally, the orthographic projection of the fifth positive electrode tab 55 completely covers the orthographic projections of the third positive electrode tab 53 and the fourth positive electrode tab 54.

[0198] As shown above, the alignment of the third positive electrode tab 53 and the fifth positive electrode tab 55 along the thickness direction of the core is achieved, as is the alignment of the fourth positive electrode tab 54 and the fifth positive electrode tab 55 along the thickness direction of the core. This improves the uniformity of current distribution and facilitates the transfer welding operation between the positive electrode tab 5 and the positive electrode adapter piece, thereby improving the welding quality.

[0199] In some embodiments, on the center plane of the core, the orthographic projections of the third negative electrode tab 63 and the fourth negative electrode tab 64 at least partially overlap with the orthographic projection of the fifth negative electrode tab 65. Optionally, the orthographic projections of the third negative electrode tab 63 and the fourth negative electrode tab 64 completely overlap with the orthographic projection of the fifth negative electrode tab 65.

[0200] As shown above, the third negative electrode tab 63 and the fifth negative electrode tab 65 are aligned along the thickness direction of the core, as are the fourth negative electrode tab 64 and the fifth negative electrode tab 65, which improves the uniformity of current distribution and facilitates the welding operation of the negative electrode tab 6 and the negative electrode adapter piece, thereby improving the welding quality.

[0201] In some embodiments of this application, the orthographic projections of the third positive electrode tab 53 and the fourth positive electrode tab 54 do not overlap on the center surface of the core.

[0202] As shown above, in the first paragraph 3, the third positive electrode tab 53 and the fourth positive electrode tab 54 are staggered (the staggered setting means that the two are not aligned along the thickness direction). The positive electrode tabs 5 are arranged in two columns, which avoids the excessive total thickness of the positive electrode tabs 5 caused by the single-layer stacking arrangement, and makes the welding positions of the two staggered, reliably avoiding welding interference, facilitating the weldability of the electrode tabs, and meeting the requirements of process manufacturability.

[0203] In some embodiments, the orthographic projections of the third negative tab 63 and the fourth negative tab 64 do not overlap on the center plane of the core.

[0204] As shown above, in the first section 3, the third negative electrode tab 63 and the fourth negative electrode tab 64 are staggered along the thickness direction of the core. The negative electrode tabs 6 are arranged in two columns, which avoids the excessive total thickness of the negative electrode tabs 6 caused by the single-layer stacking arrangement, and makes the welding positions of the two staggered, reliably avoiding welding interference, facilitating the weldability of the tabs, and meeting the requirements of process manufacturability.

[0205] In some embodiments of this application, the third positive electrode 53 is located in an odd-numbered layer, and the fourth positive electrode 54 is located in an even-numbered layer.

[0206] As shown above, in the first section 3, the alternating staggered arrangement of the third positive electrode tab 53 located in the odd-numbered layer and the fourth positive electrode tab 54 located in the even-numbered layer is realized. The arrangement of the positive electrode tabs 5 in two columns is simple and easy to process. This not only avoids the excessive total thickness of the positive electrode tabs 5 caused by the single-layer stacking arrangement, but also makes the welding positions of the two staggered, reliably avoiding welding interference, facilitating the weldability of the positive electrode tabs 5, and meeting the requirements of process manufacturability.

[0207] In some embodiments, the third negative electrode tab 63 is located in an odd-numbered layer, and the fourth negative electrode tab 64 is located in an even-numbered layer.

[0208] As shown above, in the first section 3, the alternating staggered arrangement of the third negative electrode tab 63 located in the odd-numbered layer and the fourth negative electrode tab 64 located in the even-numbered layer is realized. The arrangement of the negative electrode tabs 6 in two columns is simple and easy to process. It not only avoids the excessive total thickness of the negative electrode tabs 6 caused by the single-layer stacking arrangement, but also makes the welding positions of the two staggered, reliably avoiding welding interference, facilitating the weldability of the negative electrode tabs 6, and meeting the requirements of process manufacturability.

[0209] In some embodiments of this application, on the center surface of the core, the orthographic projections of the first positive electrode tab 51 and the third positive electrode tab 53 at least partially overlap; optionally, they completely overlap. The orthographic projections of the second positive electrode tab 52 and the fourth positive electrode tab 54 at least partially overlap; optionally, they completely overlap.

[0210] As shown above, from the perspective of the entire core, the staggered arrangement of the positive electrode tabs 5 has only two rows, which ensures the orderly and regular arrangement of all the positive electrode tabs 5. This not only improves the uniformity of current distribution, but also facilitates the transfer welding operation between all the positive electrode tabs 5 and the positive electrode adapter piece, thus improving the welding quality.

[0211] In some embodiments, on the center plane of the core, the orthographic projections of the first negative electrode tab 61 and the third negative electrode tab 63 at least partially overlap; optionally, they completely overlap. The orthographic projections of the second negative electrode tab 62 and the fourth negative electrode tab 64 at least partially overlap; optionally, they completely overlap.

[0212] As shown above, from the perspective of the entire core, the staggered arrangement of the negative electrode tabs 6 has only two rows, which ensures the orderly and regular arrangement of all negative electrode tabs 6. This not only improves the uniformity of current distribution, but also facilitates the transfer welding operation between all negative electrode tabs 6 and the negative electrode adapter piece, thus improving the welding quality.

[0213] Please see the appendix Figure 13-15 In some embodiments of this application, the sixth positive electrode arrangement rule is based on the third positive electrode arrangement rule, with a sixth positive electrode 56 added; the positive electrode 5 can be set by selectively selecting at least some layers of positive electrode unit layers 1 in all positive electrode unit layers 1 of the second segment 4 according to the sixth positive electrode arrangement rule; specifically:

[0214] In the second section 4, along the direction from the side near the center surface of the core to the side away from the center surface of the core, the outer part of the positive electrode unit layer 1 of the first positive electrode tab 51 and the second positive electrode tab 52 is provided with a sixth positive electrode tab 56. On the center surface of the core, the orthographic projection of the sixth positive electrode tab 56 overlaps with the orthographic projection of the fifth positive electrode tab 55.

[0215] Optionally, on the center plane of the core, the orthographic projection of the sixth positive tab 56 completely overlaps with the orthographic projection of the fifth positive tab 55.

[0216] A sixth positive electrode tab 56 is provided on the outer portion of the positive electrode unit layer 1, beyond the first positive electrode tab 51 and the second positive electrode tab 52. This further enriches the arrangement of the positive electrode tabs 5 in the second section 4, allowing users to flexibly choose according to their actual needs. The orthographic projection of the sixth positive electrode tab 56 overlaps with the orthographic projection of the fifth positive electrode tab 55, further enhancing the orderly and regular arrangement of all positive electrode tabs 5 along the thickness direction of the entire core. This not only improves the uniformity of current distribution but also facilitates the transfer welding operation between all positive electrode tabs 5 and the positive electrode adapter piece, thus improving welding quality.

[0217] Please see the appendix Figure 13-15In some embodiments, the sixth negative electrode tab arrangement rule is based on the third negative electrode tab arrangement rule, with a sixth negative electrode tab 66 added; the negative electrode tab 6 can be set by selectively selecting at least some layers of negative electrode sheet unit layers 2 in all negative electrode sheet unit layers 2 of the second segment 4 according to the sixth negative electrode tab arrangement rule; specifically:

[0218] The outer portion of the negative electrode sheet unit layer 2 of the first negative electrode tab 61 and the second negative electrode tab 62 is provided with a sixth negative electrode tab 66. On the center surface of the core, the orthographic projection of the sixth negative electrode tab 66 overlaps with the orthographic projection of the fifth negative electrode tab 65.

[0219] Optionally, on the center plane of the core, the orthographic projection of the sixth negative electrode tab 66 completely overlaps with the orthographic projection of the fifth negative electrode tab 65.

[0220] A sixth negative electrode tab 66 is provided on the outer portion of the positive electrode unit layer 1, beyond the first negative electrode tab 61 and the second negative electrode tab 62. This further enriches the arrangement of the negative electrode tabs 6 in the second section 4, allowing users to flexibly choose according to their actual needs. The orthographic projection of the sixth negative electrode tab 66 overlaps with the orthographic projection of the fifth negative electrode tab 65, further enhancing the orderly and regular arrangement of all negative electrode tabs 6 along the thickness direction of the entire core. This not only improves the uniformity of current distribution but also facilitates the transfer welding operation between all negative electrode tabs 6 and the negative electrode adapter piece, thus improving welding quality.

[0221] In some embodiments of this application, along the thickness direction of the core, from one side of the core to the other side, the height of each positive electrode tab 5 on each positive electrode unit layer 1 increases sequentially. It should be noted that the height of the positive electrode tab 5 is the length by which the positive electrode tab 5 extends outward relative to the electrode assembly along the length direction of the core.

[0222] As shown above, when welding the positive electrode tab 5 and the positive electrode adapter piece, the core needs to be laid flat, and the welding head should be pressed down from top to bottom along the thickness direction of the core. When the core is laid flat, the height of the positive electrode tab 5 that is closer to the top of the core is increased, ensuring that the height of the positive electrode tab 5 located on the top of the core is long enough to prevent poor welding.

[0223] In some embodiments, along the thickness direction of the core, from one side of the core to the other side, the height of each negative electrode tab 6 on each negative electrode unit layer 2 increases sequentially. It should be noted that the height of the negative electrode tab 6 is the length by which the negative electrode tab 6 extends outward relative to the electrode assembly along the length direction of the core.

[0224] As shown above, when welding the negative electrode tab 6 and the negative electrode adapter piece, the core needs to be laid flat, and the welding head should be pressed down from top to bottom along the thickness direction of the core. When the core is laid flat, the extension length of the negative electrode tab 6 that is closer to the top of the core is longer, ensuring that the extension length of the negative electrode tab 6 located on the top of the core is long enough to prevent poor welding.

[0225] Example 1

[0226] In the first section (3), each positive electrode unit layer 1 is provided with one positive electrode tab 5, and each negative electrode unit layer 2 is provided with one negative electrode tab 6; in the second section (4), positive electrode tabs 5 are provided in positive electrode unit layer 1 according to the first arrangement rule, and negative electrode tabs 6 are provided in negative electrode unit layer 2 according to the first arrangement rule; specifically:

[0227] The first segment 3 includes a 40-layer positive electrode unit layer 1 and a 41-layer negative electrode unit layer 2, and correspondingly includes a 40-layer positive electrode tab 5 and a 41-layer negative electrode tab;

[0228] The second segment 4 includes 40 layers of positive electrode unit layer 1 and 41 layers of negative electrode unit layer 2. Layers 1-11 and layers 32-40 of the positive electrode unit layer 1 do not have positive electrode tabs 5, while each layer of the positive electrode unit layer 1 from layers 12-31 has one positive electrode tab 5. Similarly, layers 1-11 and layers 33-41 of the negative electrode unit layer 2 do not have negative electrode tabs 6, while each layer of the negative electrode unit layer 2 from layers 12-32 has one negative electrode tab 6. Therefore, the second segment 4 includes 20 layers of positive electrode tabs 5 and 21 layers of negative electrode tabs 6.

[0229] Example 2

[0230] In the first section, 3, each positive electrode unit layer 1 is provided with one positive electrode tab 5, and each negative electrode unit layer 2 is provided with one negative electrode tab 6; in the second section, 4, positive electrode tabs 5 are provided in positive electrode unit layer 1 according to the second arrangement rule for positive electrode tabs, and negative electrode tabs 6 are provided in negative electrode unit layer 2 according to the second arrangement rule for negative electrode tabs; specifically:

[0231] The first segment 3 includes a 40-layer positive electrode unit layer 1 and a 41-layer negative electrode unit layer 2, and correspondingly includes a 40-layer positive electrode tab 5 and a 41-layer negative electrode tab;

[0232] The second section 4 includes 40 layers of positive electrode unit layer 1 and 41 layers of negative electrode unit layer 2. Layers 1-11 and layers 32-40 of the positive electrode unit layer 1 do not have positive electrode tabs 5. Layer 12 of the positive electrode unit layer 1 has one positive electrode tab 5. In layers 13-31 of the positive electrode unit layer 1, every two consecutive layers after a two-layer interval have one positive electrode tab 5, that is, layers 15, 16, 19, 20, 23, 24, 27, 28, and 31 each have one positive electrode tab 5. Layers 1-11 and layers 32-41 (negative electrode unit layer 1) do not have negative electrode tabs 6. Layer 12 (negative electrode unit layer 2) has one negative electrode tab 6. In layers 13-31, every two consecutive layers of negative electrode unit layer 2 after a two-layer interval have one negative electrode tab 6. That is, layers 15, 16, 19, 20, 23, 24, 27, 28, and 31 each have one positive electrode tab 5. Therefore, the second section includes 10 layers of positive electrode tabs 5 and 10 layers of negative electrode tabs 6.

[0233] Example 3

[0234] In the first section, 3, each positive electrode unit layer 1 is provided with one positive electrode tab 5, and each negative electrode unit layer 2 is provided with one negative electrode tab 6; in the second section, 4, positive electrode tabs 5 are provided in positive electrode unit layer 1 according to the third rule for positive electrode tab arrangement, and negative electrode tabs 6 are provided in negative electrode unit layer 2 according to the third rule for negative electrode tab arrangement; specifically:

[0235] The first segment 3 includes a 40-layer positive electrode unit layer 1 and a 41-layer negative electrode unit layer 2, and correspondingly includes a 40-layer positive electrode tab 5 and a 41-layer negative electrode tab;

[0236] The second segment 4 includes 40 layers of positive electrode unit 1 and 41 layers of negative electrode unit 2. In the 1st to 40th layers of positive electrode unit 1, each odd-numbered layer has a first positive electrode tab 51, and each even-numbered layer has a second positive electrode tab 52. In the 2nd layers of negative electrode unit 2, each odd-numbered layer has a first negative electrode tab 61, and each even-numbered layer has a second negative electrode tab 62. Therefore, the second segment 4 includes 40 layers of positive electrode tabs 5 and 41 layers of negative electrode tabs 6.

[0237] Example 4

[0238] The first section 3 includes 40 layers of positive electrode unit 1 and 41 layers of negative electrode unit 2. In the first 30 layers of positive electrode unit 1, each odd-numbered layer has a third positive electrode tab 53, and each even-numbered layer has a fourth positive electrode tab 54; each of the 31st to 40th layers of positive electrode unit 1 has a fifth positive electrode tab 55. In the first 31st layers of positive electrode unit 1, each odd-numbered layer of negative electrode unit 2 has a third negative electrode tab 63, and each even-numbered layer has a fourth negative electrode tab 64; each of the 32nd to 41st layers of negative electrode unit 2 has a fifth negative electrode tab 65.

[0239] The second section 4 includes 40 layers of positive electrode unit 1 and 41 layers of negative electrode unit 2. In the first 30 layers of positive electrode unit 1, each odd-numbered layer has a first positive electrode tab 51, each even-numbered layer has a second positive electrode tab 52, and each of the 31st to 40th layers has a sixth positive electrode tab 56. In the first 32 layers of negative electrode unit 2, each odd-numbered layer has a first negative electrode tab 61, each even-numbered layer has a second negative electrode tab 62, and each of the 32nd to 41st layers has a sixth negative electrode tab 66.

[0240] Based on the aforementioned winding core, this application embodiment also provides a battery comprising the winding core as described above.

[0241] Since the battery in this embodiment includes the winding core described above, the beneficial effects of the battery brought by the winding core are described above and will not be repeated here.

[0242] In some embodiments of this application, the battery can be a rechargeable battery, which refers to a battery that can be recharged after discharge to activate the active materials and continue to be used. The battery can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application does not limit this type. As an example, the battery can be a cylindrical battery, a prismatic battery, other batteries with a rigid casing and an explosion-proof valve, or other shapes of batteries. Prismatic batteries include prismatic batteries, blade-shaped batteries, and multi-prismatic batteries, such as hexagonal prismatic batteries, etc., and this application does not have any particular limitations.

[0243] The battery mentioned in the embodiments of this application refers to a single physical module that includes one or more batteries to provide higher voltage and capacity.

[0244] In some embodiments, the battery can be a battery module, and when there are multiple batteries, the multiple batteries are arranged and fixed to form a battery module.

[0245] In some embodiments, the battery may be a battery pack, which includes a housing and a battery, with the battery or battery module housed within the housing.

[0246] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0247] Based on the battery described above, this application embodiment also provides an electrical device that includes the battery as described above.

[0248] Since the electrical device in this application embodiment includes the battery described above, the beneficial effects of the battery on the electrical device are described above and will not be repeated here.

[0249] Multiple batteries can directly power electrical devices, or they can be connected in parallel, series, or a hybrid configuration to form a power supply unit, such as a battery module, to power various electrical devices. Electrical devices can include automobiles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Automobiles can be gasoline-powered, natural gas-powered, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This article does not impose any special restrictions on the aforementioned electrical devices.

[0250] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not restrict this application from necessarily using the aforementioned specific details for implementation.

[0251] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0252] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0253] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0254] It should be understood that the qualifiers “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0255] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A type of winding core, characterized in that, include: An electrode assembly includes at least one positive electrode and at least one negative electrode. The electrode assembly is continuously wound from the inner starting end of the core to the outer ending end of the core, forming multiple stacked positive electrode unit layers and negative electrode unit layers. The core has a core center surface perpendicular to the thickness direction of the core. The electrode assembly located on one side of the core center surface is a first segment, and the electrode assembly located on the other side of the core center surface is a second segment. in; At least a portion of the positive electrode unit layers in the first segment are provided with at least one positive electrode tab; at least a portion of the positive electrode unit layers in the second segment are provided with at least one positive electrode tab; And / or, At least a portion of the negative electrode unit layers in the first segment are provided with at least one negative electrode tab; at least a portion of the negative electrode unit layers in the second segment are provided with at least one negative electrode tab.

2. The winding core according to claim 1, characterized in that, In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, The positive electrode unit layers from the 1st to the nth layer do not have positive electrode tabs, while the positive electrode unit layers from the (n+1)th to the bth layer each have one positive electrode tab; where 5≤n≤15, (n+1)≤b, b≤a, and a is the total number of positive electrode unit layers in the second segment. And / or, The negative electrode unit layers from layer 1 to layer n do not have negative electrode tabs, while the negative electrode unit layers from layer n+1 to layer d each have one negative electrode tab; where 5≤n≤15, (n+1)≤d, d≤c, and c is the total number of negative electrode unit layers in the second segment.

3. The winding core according to claim 1, characterized in that, In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, The positive electrode unit layers from layer 1 to layer n do not have positive electrode tabs. The positive electrode unit layer from layer n+1 has one positive electrode tab. In the positive electrode unit layers from layer n+2 to layer b, one positive electrode tab is provided in every y consecutive positive electrode unit layers after every x layers. Wherein, 5≤n≤15, (n+1)≤b, b≤a, 2≤x≤5, 2≤y≤5, and a is the total number of positive electrode unit layers in the second segment. And / or, The negative electrode unit layers from layer 1 to layer n do not have negative electrode tabs. The negative electrode unit layer from layer n+1 has one negative electrode tab. In the negative electrode unit layers from layer n+2 to layer d, one negative electrode tab is provided for every consecutive y negative electrode unit layers after every x layers. Wherein, 5≤n≤15, (n+1)≤d, d≤c, 2≤x≤5, 2≤y≤5, and c is the total number of negative electrode unit layers in the second segment.

4. The winding core according to claim 2 or 3, characterized in that, When a≤30, then (n+1)≤b≤a; When 30 < a ≤ 40, then (n+1) < b ≤ a * 6 / 7; When 40 < a ≤ 45, then (n+1) ≤ b ≤ a * 2 / 3; When 45 < a ≤ 50, then (n+1) ≤ b ≤ a * 1 / 2; When 50 < a ≤ 55, then (n+1) ≤ b ≤ a * 2 / 5; When 55 < a ≤ 60, then (n+1) ≤ b ≤ a * 2 / 7; When 60 < a ≤ 65, then (n+1) ≤ b ≤ a * 1 / 8; When 65 < a ≤ 70, then (n+1) ≤ b ≤ a * 2 / 13; When 70 < a ≤ 75, then (n+1) ≤ b ≤ a * 1 / 15; And / or, When c≤30, then (n+1)≤d≤c; When 30 < c ≤ 40, then (n+1) < d ≤ c * 6 / 7; When 40 < c ≤ 45, then (n+1) ≤ d ≤ c * 2 / 3; When 45 < c ≤ 50, then (n+1) ≤ d ≤ c * 1 / 2; When 50 < c ≤ 55, then (n+1) ≤ d ≤ c * 2 / 5; When 55 < c ≤ 60, then (n+1) ≤ d ≤ c * 2 / 7; When 60 < c ≤ 65, then (n+1) ≤ d ≤ c * 1 / 8; When 65 < c ≤ 70, then (n+1) ≤ d ≤ c * 2 / 13; When 70 < c ≤ 75, then (n+1) ≤ d ≤ c * 1 / 15; And / or, a < c.

5. The winding core according to claim 1, characterized in that, In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, In the positive electrode unit layers from the vth layer to the wth layer, at least a portion of the odd-numbered positive electrode unit layers are provided with a first positive electrode tab, and at least a portion of the even-numbered positive electrode unit layers are provided with a second positive electrode tab. On the center surface of the core, the orthographic projection of the first positive electrode tab and the orthographic projection of the second positive electrode tab do not overlap; wherein, 1≤v<a, v≤w≤a, and a is the total number of positive electrode unit layers in the second segment; And / or, In the negative electrode unit layers from the vth layer to the wth layer, at least a portion of the odd-numbered negative electrode unit layers are provided with a first negative electrode tab, and at least a portion of the even-numbered negative electrode unit layers are provided with a second negative electrode tab. On the center surface of the core, the orthographic projection of the first negative electrode tab and the orthographic projection of the second negative electrode tab do not overlap; wherein, 1≤v<a, v<w≤c, and c is the total number of negative electrode unit layers in the second segment.

6. The winding core according to claim 5, characterized in that, From the v-th layer to the w-th layer, the number of odd-numbered layers is f1, and the number of even-numbered layers is f2; where: When a ≤ 40, then 0 < f1 ≤ a / 2; 0 < f2 ≤ a / 2; When 40 < a ≤ 45, then 0 < f1 ≤ a / 3 and 0 < f2 ≤ a / 3; When 45 < a ≤ 50, then 0 < f1 ≤ a * 1 / 5 and 0 < f2 ≤ a * 1 / 5. When 50 < a ≤ 55, then 0 < f1 ≤ a * 1 / 10 and 0 < f2 ≤ a * 1 / 10. And / or, When c≤40, then 0<f1≤a / 2; 0<f2≤a / 2; When 40 < c ≤ 45, then 0 < f1 ≤ a / 3 and 0 < f2 ≤ a / 3; When 45 < c ≤ 50, then 0 < f1 ≤ a * 1 / 5 and 0 < f2 ≤ a * 1 / 5. When 50 < c ≤ 55, then 0 < f1 ≤ a * 1 / 10 and 0 < f2 ≤ a * 1 / 10.

7. The winding core according to any one of claims 5-6, characterized in that, In the first segment, a portion of the positive electrode unit layer is provided with a fifth positive electrode tab, a portion of the positive electrode unit layer is provided with a third positive electrode tab, and a portion of the positive electrode unit layer is provided with a fourth positive electrode tab; along the direction from the side near the center surface of the core to the side away from the center surface of the core, the fifth positive electrode tab is located outside the third positive electrode tab and the fourth positive electrode tab, and the area of ​​the third positive electrode tab and the area of ​​the fourth positive electrode tab are both smaller than the area of ​​the fifth positive electrode tab; And / or, In the first segment, a portion of the positive electrode unit layer is provided with a fifth negative electrode tab, a portion of the negative electrode unit layer is provided with a third negative electrode tab, and a portion of the negative electrode unit layer is provided with a fourth negative electrode tab; along the direction from the side near the center surface of the core to the side away from the center surface of the core, the fifth negative electrode tab is located outside the third negative electrode tab and the fourth negative electrode tab, and the area of ​​the third negative electrode tab and the area of ​​the fourth negative electrode tab are both smaller than the area of ​​the fifth negative electrode tab.

8. The winding core according to claim 7, characterized in that, On the center surface of the core, the orthographic projections of the third positive electrode tab and the fourth positive electrode tab both at least partially overlap with the orthographic projection of the fifth positive electrode tab; and / or On the center surface of the core, the orthographic projections of the third negative electrode tab and the fourth negative electrode tab both at least partially overlap with the orthographic projection of the fifth negative electrode tab.

9. The winding core according to claim 7, characterized in that, On the center surface of the core, the orthographic projection of the third positive electrode tab and the orthographic projection of the fourth positive electrode tab do not overlap; and / or On the center surface of the core, the orthographic projections of the third negative electrode tab and the fourth negative electrode tab do not overlap.

10. The winding core according to claim 7, characterized in that, Along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, The third positive electrode tab is located in an odd-numbered layer, and the fourth positive electrode tab is located in an even-numbered layer; and / or The third negative electrode tab is located in an odd-numbered layer, and the fourth negative electrode tab is located in an even-numbered layer.

11. The winding core according to claim 7, characterized in that, On the center surface of the core, the orthographic projections of the first positive electrode tab and the third positive electrode tab at least partially overlap, and the orthographic projections of the second positive electrode tab and the fourth positive electrode tab at least partially overlap. and / or On the center surface of the core, the orthographic projections of the first negative electrode tab and the third negative electrode tab at least partially overlap, and the orthographic projections of the second negative electrode tab and the fourth negative electrode tab at least partially overlap.

12. The winding core according to any one of claims 8-11, characterized in that, In the second segment, along the direction from the side closest to the center surface of the core to the side furthest from the center surface of the core, A sixth positive electrode is provided on the outer portion of the positive electrode unit layer of the first and second positive electrode tabs. On the center surface of the core, the orthographic projection of the sixth positive electrode tab overlaps with the orthographic projection of the fifth positive electrode tab. And / or, A sixth negative electrode tab is provided on the outer portion of the negative electrode unit layer of the first and second negative electrode tabs. On the center surface of the core, the orthographic projection of the sixth negative electrode tab overlaps with the orthographic projection of the fifth negative electrode tab.

13. The winding core according to claim 12, characterized in that, On the center surface of the core, the orthographic projection of the sixth positive electrode tab completely overlaps with the orthographic projection of the fifth positive electrode tab. and / or On the center surface of the core, the orthographic projection of the sixth negative electrode tab completely overlaps with the orthographic projection of the fifth negative electrode tab.

14. The core according to any one of claims 1-3, 5-6, 8-11, or 13, characterized in that, Along the thickness direction of the core, from one side of the core to the other side of the core, The height of each of the positive electrode tabs on each of the aforementioned positive electrode unit layers increases sequentially, and / or The height of each negative electrode tab on each negative electrode unit layer increases sequentially.

15. A battery, characterized in that, Includes the core as described in any one of claims 1-14.

16. An electrical appliance, characterized in that, Includes the battery as described in claim 15.

Images