Battery

Abstract

The utility model discloses a battery which comprises a battery cell, a first pole piece and a second pole piece are laminated and then wound to form the battery cell, the first pole piece comprises a plurality of first straight parts and a plurality of first arc parts, and the first straight parts and the first arc parts are alternately arranged along the length direction of the first pole piece; the first straight part comprises first connecting pieces, second connecting pieces and a first main body, the first connecting pieces and the second connecting pieces are connected to the first main body, the multiple first connecting pieces are connected with one another, and the multiple second connecting pieces are connected with one another; the first tab comprises a first part, a second part and a third part, the second part and the third part are both connected to the first part, the second part and the third part are located on the two sides of the first part respectively, the first part is connected to the first main body, the second part is connected to the first connecting piece, and the third part is connected to the second connecting piece; and the second tab is connected to the second pole piece. According to the battery disclosed by the utility model, the lithium precipitation condition can be effectively avoided.

Description

Technical Field

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

[0002] In the related art, a battery includes a housing and an electrode core. The electrode core is disposed inside the housing. The electrode core is made by a positive electrode sheet and a negative electrode sheet. Specifically, after the positive electrode sheet and the negative electrode sheet are respectively manufactured, the positive electrode sheet and the negative electrode sheet are stacked together, and then the two are wound to form the electrode core. Among them, when the battery is in use, the electrode core will experience multiple charge and discharge cycles. After the electrode core undergoes multiple charge and discharge cycles, since the current density at the corner of the electrode core is greater than that at other positions of the electrode core, the electrolyte at the corner of the electrode core will be consumed too fast, resulting in the appearance of lithium deposition at the corner of the electrode core. Summary of the Utility Model

[0003] The utility model aims to at least solve one of the technical problems existing in the prior art. For this purpose, the utility model provides a battery, which can effectively avoid the occurrence of lithium deposition.

[0004] The battery according to the embodiment of the utility model includes:

[0005] An electrode core, which is formed by winding after stacking a first electrode sheet and a second electrode sheet. The first electrode sheet includes a plurality of first flat portions and a plurality of first arc portions. Along the length direction of the first electrode sheet, the first flat portions and the first arc portions are alternately arranged. Along the thickness direction of the electrode core, a plurality of the first flat portions are stacked. The first flat portion includes a first connecting member, a second connecting member and a first main body. The first connecting member and the second connecting member are both connected to the first main body, and the first connecting member and the second connecting member both protrude from the first main body. A plurality of the first connecting members are connected to each other, and a plurality of the second connecting members are connected to each other;

[0006] A first tab, which includes a first portion, a second portion and a third portion. The second portion and the third portion are both connected to the first portion, and the second portion and the third portion are respectively located on both sides of the first portion. The first portion is connected to the first main body, the second portion is connected to the first connecting member, and the third portion is connected to the second connecting member;

[0007] A second tab, which is connected to the second electrode sheet.

[0008] The battery according to the embodiment of the present utility model has at least the following beneficial effects: The first pole piece of the battery cell includes a plurality of first straight portions and a plurality of first arc portions. The two ends of each first straight portion are respectively connected to two first arc portions. Along the length direction of the first pole piece, the first straight portions and the first arc portions are arranged alternately. That is, after the first pole piece is wound, the first arc portion can be the corner of the first pole piece; a plurality of first connecting members are connected to each other, and a plurality of second connecting members are connected to each other. The second portion of the first pole ear is connected to the first connecting member, and the third portion is connected to the second connecting member. Thus, the current flow path can be to enter from the first portion of the first pole ear, and then the current enters the second portion and the third portion respectively from the first portion. Since the second portion is connected to the first connecting member and the third portion is connected to the second connecting member, therefore, the current can enter the plurality of first connecting members from the second portion, and the current can enter the plurality of second connecting members from the third portion. That is, the current can enter each first straight portion and the first arc portion from the first portion; in the prior art, after the current enters the pole ear, the current needs a long path to flow into each position of the pole piece. For example, the current enters from one end of the pole piece, and then passes through a plurality of corners and multiple layers of the pole piece before the current can reach the other end of the pole piece. Therefore, the current density at the corner is relatively large; in this application, the second portion is connected to the first connecting member and the third portion is connected to the second connecting member, which can shorten the current flow path and reduce the current density at the corner of the battery cell, thereby effectively avoiding the problem of lithium deposition in the battery. Specifically, the battery can effectively avoid the occurrence of lithium deposition.

[0009] In the battery according to some embodiments of the present utility model, both the second portion and the third portion include a first section and a second section. The two ends of the second section are respectively connected to the first section and the first portion, and the first section and the first portion are arranged in parallel.

[0010] In the battery according to some embodiments of the present utility model, the distance between the first section and the first portion is A, and A≥8mm.

[0011] In the battery according to some embodiments of the present utility model, the length of the first portion is greater than the length of the first section.

[0012] In the battery according to some embodiments of the present utility model, along the width direction of the battery cell, the distance from the first section to the edge of the battery cell is B, and B≥7mm.

[0013] According to some embodiments of the present utility model, for the battery, the second electrode tab includes a plurality of second straight portions and a plurality of second arc portions. Along the length direction of the second electrode tab, the second straight portions and the second arc portions are arranged alternately. Along the thickness direction of the battery cell, a plurality of the second straight portions are stacked. The second straight portion includes a third connecting member, a fourth connecting member, and a second main body. Both the third connecting member and the fourth connecting member are connected to the second main body, and both the third connecting member and the fourth connecting member protrude from the second main body. A plurality of the third connecting members are connected to each other, and a plurality of the fourth connecting members are connected to each other;

[0014] The second electrode ear includes a fourth portion, a fifth portion, and a sixth portion. Both the fifth portion and the sixth portion are connected to the fourth portion, and the fifth portion and the sixth portion are respectively located on both sides of the fourth portion. The fourth portion is connected to the second main body, the fifth portion is connected to the third connecting member, and the sixth portion is connected to the fourth connecting member.

[0015] According to some embodiments of the present utility model, for the battery, both the fifth portion and the sixth portion include a third section and a fourth section. Two ends of the fourth section are respectively connected to the third section and the fourth portion, and the third section and the fourth portion are arranged in parallel.

[0016] According to some embodiments of the present utility model, for the battery, the length by which the first portion protrudes from the battery cell is C, and 12 mm ≤ C ≤ 15 mm.

[0017] According to some embodiments of the present utility model, for the battery, the lengths of both the second portion and the third portion are D, and 2.5 mm ≤ D ≤ 3.5 mm.

[0018] According to some embodiments of the present utility model, for the battery, along the width direction of the battery cell, the distance from the first portion to the edge of the battery cell is F, and F ≥ 7 mm.

[0019] Additional aspects and advantages of the present utility model will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following further describes the present utility model in conjunction with the drawings and embodiments, where:

[0021] Figure 1 is a schematic diagram of the battery according to the first embodiment of the present utility model;

[0022] Figure 2 is a schematic diagram of the battery according to the second embodiment of the present utility model;

[0023] Figure 3Schematic diagram of the battery according to the third embodiment of the present utility model;

[0024] Figure 4 Cross-sectional schematic diagram of the battery cell in the battery according to some embodiments of the present utility model;

[0025] Figure 5 Schematic diagram of the unfolded first pole piece in the battery according to some embodiments of the present utility model;

[0026] Figure 6 Schematic diagram of the unfolded second pole piece in the battery according to some embodiments of the present utility model;

[0027] Figure 7 Schematic diagram of the first pole ear in the battery according to some embodiments of the present utility model;

[0028] Figure 8 Schematic diagram of the second pole ear in the battery according to some embodiments of the present utility model.

[0029] Reference numerals:

[0030] Battery 10, battery cell 100, first pole piece 200, first straight portion 210, first connecting member 220, second connecting member 230, first main body 240, first arc portion 250, second pole piece 300, second straight portion 310, third connecting member 320, fourth connecting member 330, second main body 340, second arc portion 350, first pole ear 400, first portion 410, second portion 420, third portion 430, first section 450, second section 460, second pole ear 500, fourth portion 510, fifth portion 520, sixth portion 530, third section 540, fourth section 550. Detailed description of the specific implementation

[0031] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.

[0032] In the description of the present utility model, it should be understood that for the orientation description, such as up, down, front, back, left, right, etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0033] In the description of the present utility model, the meaning of "several" is more than one, the meaning of "multiple" is more than two, and understandings such as "greater than", "less than", "exceeding", etc. do not include the corresponding number, and understandings such as "above", "below", "within", etc. include the corresponding number. If there is a description of "first", "second", etc., it is only for the purpose of distinguishing technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0034] In the description of the present utility model, unless otherwise clearly defined, terms such as "arrangement", "installation", "connection", etc. should be understood in a broad sense, and those skilled in the relevant technical field can reasonably determine the specific meanings of the above terms in the present utility model in combination with the specific content of the technical solution.

[0035] In the description of the present utility model, descriptions with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0036] In the related art, the battery 10 includes a housing and an electrode core 100. The electrode core 100 is disposed inside the housing. The electrode core 100 is made by a positive electrode sheet and a negative electrode sheet. Specifically, after the positive electrode sheet and the negative electrode sheet are respectively manufactured, the positive electrode sheet and the negative electrode sheet are stacked together, and then the two are wound to form the electrode core 100. Among them, when the battery 10 is in use, the electrode core 100 will undergo multiple charge and discharge cycles. After the electrode core 100 undergoes multiple charge and discharge cycles, since the current density at the corners of the electrode core 100 is greater than that at other positions of the electrode core 100, the electrolyte at the corners of the electrode core 100 will be consumed too fast, resulting in the appearance of lithium deposition at the corners of the electrode core 100. For this reason, the present application proposes a battery 10.

[0037] Please refer to Figures 1 to 8, in some embodiments, the battery 10 includes: a battery cell 100, a first tab 400, and a second tab 500. The battery cell 100 is formed by winding after laminating a first electrode sheet 200 and a second electrode sheet 300. For example, after laminating the first electrode sheet 200, the separator, and the second electrode sheet 300, the three are wound to form the battery cell 100. This part belongs to the prior art and will not be elaborated herein. It can be conceived that the shape of the battery cell 100 can be square. After winding the first electrode sheet 200, the first electrode sheet 200 includes a plurality of first flat portions 210 and a plurality of first arc portions 250. The first flat portion 210 specifically refers to the part of the first electrode sheet 200 without an arc bend after winding the first electrode sheet 200, and the first arc portion 250 specifically refers to the corner of the first electrode sheet 200 after winding the first electrode sheet 200. Both ends of each first flat portion 210 are respectively connected to two first arc portions 250, that is, both ends of one first flat portion 210 are respectively connected to two first arc portions 250, and both ends of one first arc portion 250 are respectively connected to two first flat portions 210. In other words, when the first electrode sheet 200 is flattened, along the length direction of the first electrode sheet 200, the first flat portions 210 and the first arc portions 250 are alternately arranged. Along the thickness direction of the battery cell 100, a plurality of first flat portions 210 are stacked. The specific stacking of a plurality of first flat portions 210 means that a plurality of first flat portions 210 are arranged in the thickness direction of the battery cell 100, and adjacent two first flat portions 210 are indirectly connected. The first flat portion 210 includes a first connecting member 220, a second connecting member 230, and a first main body 240. Both the first connecting member 220 and the second connecting member 230 are connected to the first main body 240, and both the first connecting member 220 and the second connecting member 230 protrude from the first main body 240. A plurality of first connecting members 220 are connected to each other, and a plurality of second connecting members 230 are connected to each other. That is, after winding the first electrode sheet 200, along the thickness direction of the battery cell 100, a plurality of first connecting members 220 are stacked together, and a plurality of second connecting members 230 are stacked together. The first tab 400 includes a first portion 410, a second portion 420, and a third portion 430. Both the second portion 420 and the third portion 430 are connected to the first portion 410, and the second portion 420 and the third portion 430 are respectively located on both sides of the first portion 410. The first portion 410 is connected to the first main body 240, the second portion 420 is connected to the first connecting member 220, and the third portion 430 is connected to the second connecting member 230. The second tab 500 is connected to the second electrode sheet 300.

[0038] Specifically, the first electrode tab 200 of the battery cell 100 includes a plurality of first straight portions 210 and a plurality of first arc portions 250. Both ends of each first straight portion 210 are respectively connected to two first arc portions 250. That is, after the first electrode tab 200 is wound, the first arc portions 250 can be the corners of the first electrode tab 200. A plurality of first connecting members 220 are connected to each other, and a plurality of second connecting members 230 are connected to each other. The second portion 420 of the first electrode ear 400 is connected to the first connecting member 220, and the third portion 430 is connected to the second connecting member 230. Thus, the current flow path can be to enter from the first portion 410 of the first electrode ear 400, and then the current enters the second portion 420 and the third portion 430 from the first portion 410 respectively. Since the second portion 420 is connected to the first connecting member 220 and the third portion 430 is connected to the second connecting member 230, therefore, the current can enter the plurality of first connecting members 220 from the second portion 420, and the current can enter the plurality of second connecting members 230 from the third portion 430. That is, the current can enter each first straight portion 210 and the first arc portion 250 from the first portion 410. In the prior art, after the current enters the electrode ear, the current needs a long path to flow into each position of the electrode tab. For example, when the current enters from one end of the electrode tab, and then passes through a plurality of corners and multiple layers of the electrode tab, the current can reach the other end of the electrode tab. Therefore, the current density at the corner is relatively large. In this application, the second portion 420 is connected to the first connecting member 220, and the third portion 430 is connected to the second connecting member 230, which can shorten the current flow path, reduce the current density at the corner of the battery cell 100, and thus effectively avoid the problem of lithium plating in the battery 10. Specifically, the battery 10 can effectively avoid the occurrence of lithium plating.

[0039] The following is a further description. In the prior art, the first electrode ear 400 is connected to the middle position of the first electrode tab 200, and the first electrode tab 200 does not include the first connecting member 220 and the second connecting member 230. After the current enters from the first electrode ear 400, the current can flow to both ends of the first electrode tab 200. In the case where the first electrode tab 200 is wound, the current flows to the winding start point and the winding end point of the first electrode tab 200. That is, half of the current reaches one end of the first electrode tab 200, and the other half of the current flows to the other end of the first electrode tab 200, which will result in a relatively large current density at the corner of the battery cell 100. The corner of the battery cell 100 is the winding bend of the first electrode tab 200. Refer to Figure 5, taking the example that the first tab 400 is connected to the middle position of the first electrode tab 200. In the present application, after the first connecting member 220 and the second connecting member 230 are provided, when the current enters from the first tab 400, the current will enter into a plurality of first connecting members 220 and a plurality of second connecting members 230. The plurality of first connecting members 220 and the plurality of second connecting members 230 can play a role in current shunting, thereby reducing the current density at the corner of the battery cell 100. In addition, it should be noted that after the first connecting member 220 and the second connecting member 230 are provided, the flow path of the current can also be shortened, thereby improving the charging rate of the battery 10.

[0040] Furthermore, the first electrode tab 200 can be a positive electrode tab, the first electrode tab 200 can be a negative electrode tab, and the second electrode tab 300 can also be a positive electrode tab or a negative electrode tab. Among them, the number of the first tab 400 and the second tab 500 can both be one. An empty foil area (an area without an active material layer) is provided on the first electrode tab 200 for welding with the first tab 400. The plurality of first connecting members 220 can be connected to each other by welding. The plurality of second connecting members 230 can be connected to each other by welding. Among them, when manufacturing the first electrode tab 200, the first connecting member 220 and the second connecting member 230 can be obtained by cutting the foil. In addition, the first tab 400 can be connected to the middle position or the edge position of the first electrode tab 200, and the second tab 500 can be connected to the middle position or the edge position of the second electrode tab 300. When the first tab 400 is located at the middle position of the first electrode tab 200, the charging speed of the battery 10 can be improved, and the high-rate discharge capacity can also be enhanced. When the first electrode tab 200 is a positive electrode tab, the impedance of the first electrode tab 200 is small, and the temperature of the first electrode tab 200 during charging and discharging is relatively low.

[0041] Furthermore, please refer to Figure 7 , the structure of the first tab 400 will be specifically introduced below. In some embodiments, both the second part 420 and the third part 430 include a first section 450 and a second section 460. The two ends of the second section 460 are respectively connected to the first section 450 and the first part 410, and the first section 450 and the first part 410 are arranged in parallel. The shape of the first tab 400 can be similar to a "mountain" shape. Among them, the "mountain" shape setting can enable the current to flow to both ends of the first electrode tab 200 respectively after the first tab 400 is connected to the first electrode tab 200, thereby achieving the effects of short current path and low current density. In addition, the first tab 400 can be formed by a cutting process.

[0042] Furthermore, please refer to Figure 7, in some embodiments, the distance between the first section 450 and the first part 410 is A, where A ≥ 8 mm. Specifically, A can be 8 mm, 9 mm, 10 mm, or 12 mm, etc. It can be understood that the specific way the second part 420 is connected to the first connecting member 220 and the third part 430 is connected to the second connecting member 230 can be that the second part 420 is welded to the first connecting member 220 and the third part 430 is welded to the second connecting member 230. Therefore, when the distance between the first section 450 and the first part 410 is less than 8 mm, due to the excessively small distance between the first section 450 and the first part 410, this will result in a relatively small space when welding the first connecting member 220 and the second part 420 as well as the second connecting member 230 and the third part 430, making the welding difficult.

[0043] Further, please refer to Figure 7 , in some embodiments, the length of the first part 410 is greater than the length of the first section 450. Specifically, the length of the first part 410 being greater than the length of the first section 450 can be that the length of the first part 410 is greater than the length of the second part 420 and the length of the first part 410 is greater than the length of the third part 430. It can be understood that the first part 410 can be electrically connected to the outside, thereby enabling charging and discharging between the battery 10 and external devices. The second part 420 and the third part 430 mainly play a role in shunting. The lengths of the second part 420 and the second part 420 being less than the length of the first part 410 can increase the energy density of the battery 10. Continuing to explain, the battery 10 further includes a housing, which can be a steel shell or an aluminum plastic film. The battery cell 100 is placed inside the housing, the second part 420 and the third part 430 are arranged inside the housing, and at least part of the first part 410 protrudes outside the housing.

[0044] Further, please refer to Figure 1 , in some embodiments, along the width direction of the battery cell 100, the distance from the first section 450 to the edge of the battery cell 100 is B, where B ≥ 7 mm. Among them, the distance to the edge of the battery cell 100 specifically means that when the battery cell 100 is square, the battery cell 100 includes two long sides and two short sides, and the edge of the battery cell 100 refers to the short side. Specifically, the distance from the first section 450 to the edge of the battery cell 100 can be 7 mm, 8 mm, or 9 mm. When the first section 450 is relatively close to the edge of the battery cell 100, it will cause the current density at the corner of the battery cell 100 to be too large, resulting in the appearance of the lithium plating problem.

[0045] Further, the specific structures and connection methods of the first electrode tab 200 and the first electrode ear 400 are introduced above. Now, the specific structures and connection methods of the second electrode tab 300 and the second electrode ear 500 will be introduced. Please refer to Figures 2 to 8, in some embodiments, the second pole piece 300 includes a plurality of second flat portions 310 and a plurality of second arc portions 350. The second flat portion 310 specifically may refer to the portion of the second pole piece 300 that has no arc-shaped bend after the second pole piece 300 is wound, and the second arc portion 350 specifically may refer to the corner of the second pole piece 300 after the second pole piece 300 is wound. Each end of each second flat portion 310 is respectively connected to two second arc portions 350, that is, the two ends of one second flat portion 310 are respectively connected to two second arc portions 350, and the two ends of one second arc portion 350 are respectively connected to two second flat portions 310. In other words, when the second pole piece 300 is flattened, along the length direction of the second pole piece 300, the second flat portions 310 and the second arc portions 350 are alternately arranged. Along the thickness direction of the battery cell 100, the plurality of second flat portions 310 are stacked. The plurality of second flat portions 310 being stacked specifically means that the plurality of second flat portions 310 are arranged in the thickness direction of the battery cell 100, and adjacent two second flat portions 310 are indirectly connected. The second flat portion 310 includes a third connecting member 320, a fourth connecting member 330, and a second main body 340. Both the third connecting member 320 and the fourth connecting member 330 are connected to the second main body 340, and both the third connecting member 320 and the fourth connecting member 330 protrude from the second main body 340. The plurality of third connecting members 320 are connected to each other, and the plurality of fourth connecting members 330 are connected to each other, that is, after the first pole piece 200 is wound, along the thickness direction of the battery cell 100, the plurality of first connecting members 220 are stacked together, and the plurality of second connecting members 230 are stacked together. Please refer to Figures 2 to 8, the second tab 500 includes a fourth portion 510, a fifth portion 520, and a sixth portion 530. The fifth portion 520 and the sixth portion 530 are both connected to the fourth portion 510, and the fifth portion 520 and the sixth portion 530 are respectively located on both sides of the fourth portion 510. The fourth portion 510 is connected to the second main body 340, the fifth portion 520 is connected to the third connecting member 320, and the sixth portion 530 is connected to the fourth connecting member 330. Specifically, the second electrode tab 300 includes a plurality of second straight portions 310 and a plurality of second arc portions 350. Both ends of each second straight portion 310 are respectively connected to two second arc portions 350. That is, after the second electrode tab 300 is wound, the second arc portion 350 can be the corner of the second electrode tab 300. A plurality of third connecting members 320 are connected to each other, and a plurality of fourth connecting members 330 are connected to each other. The fifth portion 520 of the second tab 500 is connected to the third connecting member 320, and the sixth portion 530 is connected to the fourth connecting member 330. Thus, the current flow path can be to enter from the fourth portion 510 of the second tab 500, and then the current enters the fifth portion 520 and the sixth portion 530 respectively from the fourth portion 510. Since the fifth portion 520 is connected to the third connecting member 320 and the sixth portion 530 is connected to the fourth connecting member 330, therefore, the current can enter the plurality of third connecting members 320 from the fifth portion 520, and the current can enter the plurality of fourth connecting members 330 from the sixth portion 530. That is, the current can enter each second straight portion 310 and the second arc portion 350 from the fourth portion 510. Thus, this can shorten the current flow path, reduce the current density at the corner of the battery cell 100, and effectively avoid the problem of lithium plating in the battery 10. In addition, the charging efficiency of the second electrode tab 300 can also be improved.

[0046] Further, the structure of the second tab 500 will be specifically introduced below. In some embodiments, both the fifth portion 520 and the sixth portion 530 include a third segment 540 and a fourth segment 550. Both ends of the fourth segment 550 are respectively connected to the third segment 540 and the fourth portion 510, and the third segment 540 and the fourth portion 510 are arranged in parallel. The shape of the second tab 500 can be similar to a "mountain" shape. Among them, the "mountain" shape setting can make the current flow to both ends of the second electrode tab 300 respectively after the second tab 500 is connected to the second electrode tab 300, so as to achieve the effects of short current path and low current density. In addition, the second tab 500 can be formed by a cutting process.

[0047] Further, in some embodiments, the length by which the first part 410 protrudes from the battery cell 100 is C, where 12 mm ≤ C ≤ 15 mm. Specifically, the length by which the first part 410 protrudes from the battery cell 100 is 12 mm, 13 mm, 14 mm, or 15 mm. Among them, when the length by which the first part 410 protrudes from the battery cell 100 is less than 12 mm, the length by which the first part 410 protrudes from the battery cell 100 is too small. Since pole ear glue is provided on the first pole ear 400, a smaller length will cause difficulties in assembling the battery 10. When the length by which the first part 410 protrudes from the battery cell 100 is greater than 15 mm, the length by which the first part 410 protrudes from the battery cell 100 is too large, which will result in waste of materials and an increase in the cost of the battery 10. It should be noted that the structure of the fourth part 510 can refer to the structure of the first part 410, that is, the length of the first part 410 is equal to the length of the fourth part 510.

[0048] Further, please refer to Figure 1 , in some embodiments, the lengths of the second part 420 and the third part 430 are both D, where 2.5 mm ≤ D ≤ 3.5 mm. Specifically, the lengths of the second part 420 and the third part 430 can be 2.5 mm, 3 mm, 3.2 mm, or 3.5 mm. Among them, when the lengths of both the second part 420 and the third part 430 are less than 2.5 mm, due to the small lengths of the second part 420 and the third part 430, the welding difficulty will be relatively high when welding the second part 420 to the first connecting member 220 and the third part 430 to the second connecting member 230. When the lengths of both the second part 420 and the third part 430 are greater than 3.5 mm, it will cause waste of materials and an increase in the cost of the battery 10. It should be noted that the structure of the second pole ear 500 can be the same as the structure of the first pole ear 400. Therefore, the length of the fifth part 520 is equal to the length of the second part 420, and the length of the sixth part 530 is equal to the length of the third part 430.

[0049] Further, please refer to Figure 1, in some embodiments, along the width direction of the battery cell 100, the distance from the first part 410 to the edge of the battery cell 100 is F, and F ≥ 7 mm. Specifically, the distance to the edge of the battery cell 100 specifically means that when the battery cell 100 is square, the battery cell 100 includes two long sides and two short sides, and the edge of the battery cell 100 refers to the short side. The distance from the first part 410 to the edge of the battery cell 100 can be 7 mm, 8 mm, or 9 mm. If the first part 410 is too close to the edge of the battery cell 100, then the space between the first part 410 and the edge of the battery cell 100 will be small. Since the second part 420 or the third part 430 is disposed between the first part 410 and the edge of the battery cell 100, therefore, when the space here is too small, it will be difficult to weld the second part 420 and the first connecting member 220, or it will be difficult to weld the third part 430 and the second connecting member 230. It should be noted that the structure of the second tab 500 can be the same as the structure of the first tab 400. Therefore, the distance from the first part 410 to the edge of the battery cell 100 can be equal to the distance from the fourth part 510 to the edge of the battery cell 100.

[0050] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made without departing from the spirit of the present invention within the knowledge scope of those of ordinary skill in the art to which the present invention pertains. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A battery, characterized in that, Comprising: A battery cell formed by winding a first electrode tab and a second electrode tab in a stacked manner. The first electrode tab includes a plurality of first flat portions and a plurality of first arc portions. Along the length direction of the first electrode tab, the first flat portions and the first arc portions are alternately arranged. Along the thickness direction of the battery cell, the plurality of first flat portions are stacked. The first flat portion includes a first connecting member, a second connecting member, and a first main body. Both the first connecting member and the second connecting member are connected to the first main body, and both the first connecting member and the second connecting member protrude from the first main body. The plurality of first connecting members are connected to each other, and the plurality of second connecting members are connected to each other; A first tab, including a first portion, a second portion, and a third portion. The second portion and the third portion are both connected to the first portion, and the second portion and the third portion are respectively located on both sides of the first portion. The first portion is connected to the first main body, the second portion is connected to the first connecting member, and the third portion is connected to the second connecting member; A second tab, connected to the second electrode tab.

2. The battery according to claim 1, wherein, Both the second portion and the third portion include a first section and a second section. Two ends of the second section are respectively connected to the first section and the first portion, and the first section and the first portion are arranged in parallel.

3. The battery according to claim 2, wherein The distance between the first section and the first portion is A, and A ≥ 8 mm.

4. The battery according to claim 2, wherein, The length of the first portion is greater than the length of the first section.

5. The battery according to claim 2, characterized in that, Along the width direction of the battery cell, the distance from the first section to the edge of the battery cell is B, and B ≥ 7 mm.

6. The battery according to claim 1, characterized in that, The second electrode tab includes a plurality of second flat portions and a plurality of second arc portions. Along the length direction of the second electrode tab, the second flat portions and the second arc portions are alternately arranged. Along the thickness direction of the battery cell, the plurality of second flat portions are stacked. The second flat portion includes a third connecting member, a fourth connecting member, and a second main body. Both the third connecting member and the fourth connecting member are connected to the second main body, and both the third connecting member and the fourth connecting member protrude from the second main body. The plurality of third connecting members are connected to each other, and the plurality of fourth connecting members are connected to each other; The second tab includes a fourth portion, a fifth portion, and a sixth portion. The fifth portion and the sixth portion are both connected to the fourth portion, and the fifth portion and the sixth portion are respectively located on both sides of the fourth portion. The fourth portion is connected to the second main body, the fifth portion is connected to the third connecting member, and the sixth portion is connected to the fourth connecting member.

7. The battery according to claim 6, wherein Both the fifth portion and the sixth portion include a third section and a fourth section. Two ends of the fourth section are respectively connected to the third section and the fourth portion, and the third section and the fourth portion are arranged in parallel.

8. The battery according to claim 1, characterized in that, The length by which the first portion protrudes from the battery cell is C, and 12 mm ≤ C ≤ 15 mm.

9. The battery according to claim 1, characterized in that, The lengths of both the second portion and the third portion are D, and 2.5 mm ≤ D ≤ 3.5 mm.

10. The battery according to claim 1, characterized in that, Along the width direction of the battery cell, the distance from the first portion to the edge of the battery cell is F, and F ≥ 7 mm.

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