Multi-electrode poles, cells and batteries
By setting a coating area and/or an empty foil area on the current collector of the battery cell electrode sheet and forming a false ear by combining metal sheets, the problem of difficult manufacturing of multi-pole ears in the prior art is solved, and more efficient battery charging is achieved.
Patent Information
- Application Number
- CN202420502201.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-14
- Publication Date
- 2025-04-01
- Estimated Expiration
- 2034-03-14
AI Technical Summary
The existing manufacturing methods of multi-pole ears on battery cells require the coordination of coating, rolling processes, etc., resulting in high manufacturing requirements and high difficulty.
A multi-pole ear pole sheet is proposed, where a coating area and/or an empty foil area are provided on the current collector, and the active material layer is coated on the coating area, and a plurality of metal sheets are spaced apart along the length direction of the current collector, and a false ear is combined to form a false ear for welding the true ear during winding.
It reduces the difficulty and requirements of multi-pole ear pole chip manufacturing, makes operation easier, and improves overcurrent capability, thereby improving the charging speed of the battery.
Smart Images
Figure CN222705772U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of lithium batteries, and in particular to a multi-electrode pole piece, a battery core and a battery. Background Art
[0002] Lithium battery refers to a battery containing lithium (including metallic lithium, lithium alloys, lithium ions, and lithium polymers) in the electrochemical system. In recent years, lithium batteries have been widely used in digital products and other fields due to their many advantages such as long cycle life, good safety performance, and rapid charging and discharging.
[0003] Lithium batteries are usually made by using winding or lamination equipment to assemble positive electrode sheets, negative electrode sheets and separators to form a battery cell, and then encapsulating the battery cell in a shell. In a battery, the number of tabs on the electrode sheet affects the internal resistance and charging speed of the battery. In order to increase the charging speed, the number of tabs on the electrode sheet is usually increased as much as possible to increase the current capacity, thereby achieving an increase in the battery charging speed.
[0004] At present, in the production process of pole pieces, the current collector of the pole piece is generally directly die-cut to form multiple pole ears, and then the multiple pole ears are overlapped to form a fake pole ear, which is welded with the real pole ear. The manufacturing method of die-cutting the current collector to make a fake pole ear requires the coordination of coating and rolling processes, resulting in high manufacturing requirements and great difficulty. Utility Model Content
[0005] The main purpose of the utility model is to propose a multi-electrode tab pole piece, aiming to solve the technical problem that the current manufacturing method of multi-electrode tabs on battery cell pole pieces requires the coordination of coating and rolling processes, resulting in high manufacturing requirements and great difficulty.
[0006] In order to achieve the above-mentioned object, the utility model provides a multi-pole ear pole piece, which comprises:
[0007] A current collector, provided with a coating area or provided with a coating area and a hollow foil area located at at least one end of the coating area;
[0008] an active material layer, applied to the coating area;
[0009] A plurality of metal sheets are located on one side of the current collector and are spaced apart along the length direction of the current collector. The plurality of metal sheets extend from one side of the current collector and are combined to form a false pole tab when the multi-pole tab pole sheets are wound to be used for welding a real pole tab;
[0010] Wherein, when the current collector is provided with the coating area, the multiple metal sheets are provided in the coating area and are welded to the current collector; when the current collector is provided with the coating area and the empty foil area, the multiple metal sheets are provided in the coating area and / or the empty foil area and are welded to the current collector.
[0011] In some embodiments, when the metal sheet is disposed in the coating area, the active material layer is configured with a welding groove adapted to the metal sheet, and the metal sheet is embedded in the welding groove.
[0012] In some embodiments, an insulating structure is disposed at a welding position of the current collector for welding the metal sheet. The insulating structure is disposed on two sides of the current collector and covers the metal sheet.
[0013] In some embodiments, the insulating structure includes insulating glue;
[0014] When the metal sheet is arranged in the coating area, the insulating glue covers the metal sheet and is bonded to the active material layer; when the metal sheet is arranged in the empty foil area, the insulating glue covers the metal sheet and is bonded to the current collector.
[0015] In some embodiments, the length of the welding groove is 5 mm to 30 mm; and / or,
[0016] The width of the welding groove is 5 mm to 30 mm.
[0017] In some embodiments, the thickness of the metal sheet is 3 μm to 100 μm; and / or,
[0018] The width of the metal sheet is 3 mm to 15 mm.
[0019] The utility model also provides a battery core, which comprises:
[0020] The battery cell body is wound;
[0021] The battery cell body comprises a positive electrode sheet and a negative electrode sheet which are stacked and wound on each other;
[0022] Wherein, the positive electrode plate includes the multi-pole tab plate as mentioned above; and / or, the negative electrode plate includes the multi-pole tab plate as mentioned above.
[0023] In some embodiments, along the thickness direction of the battery cell body, a plurality of the metal sheets in the multi-pole tab pole pieces are overlapped and stacked or staggered.
[0024] In some embodiments, the plurality of metal sheets in the multi-pole tab pole piece are bent.
[0025] The utility model also provides a battery, which comprises a shell and a battery core arranged in the shell, and the battery core is the battery core as described above.
[0026] In the multi-electrode ear pole piece of the utility model, a plurality of metal sheets spaced apart along the length direction are arranged on one side of the current collector, and a plurality of metal sheets extend from one side of the current collector. When the multi-electrode ear pole piece is wound, a plurality of metal sheets are combined to form a false pole ear for welding a true pole ear. Among them, when the current collector is provided with a coating area, a plurality of metal sheets are arranged in the coating area, and are connected to the current collector by welding; when the current collector is provided with a coating area and an empty foil area, a plurality of metal sheets are arranged in the coating area and / or the empty foil area, and are connected to the current collector by welding. Compared with the current method of manufacturing false pole ears by die-cutting the current collector, the manufacturing requirements are low, the difficulty is small, and the operation is simpler. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 It is a schematic diagram of the structure of a multi-electrode pole piece in one embodiment of the utility model;
[0028] Figure 2 It is a schematic diagram of the structure of a multi-electrode pole piece in another embodiment of the utility model;
[0029] Figure 3 This is a schematic diagram of the structure of a multi-electrode pole piece in another embodiment of the utility model;
[0030] Figure 4 This is a schematic structural diagram of a multi-electrode pole piece in yet another embodiment of the utility model;
[0031] Figure 5 It is a structural schematic diagram of a part of a multi-electrode pole piece in one embodiment of the utility model;
[0032] Figure 6 This is a schematic diagram of the structure of a battery cell in one embodiment of the utility model;
[0033] Figure 7 This is a schematic diagram of the structure of a battery cell in another embodiment of the utility model;
[0034] Figure 8 This is a schematic diagram of the structure of a battery cell in another embodiment of the utility model;
[0035] Fig. 9 This is a schematic diagram of the structure of a battery cell in yet another embodiment of the present utility model. DETAILED DESCRIPTION
[0036] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the scheme in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0037] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.
[0038] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.
[0039] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.
[0040] Based on the technical problems existing in the related prior art mentioned in the background technology, the embodiment of the utility model proposes a multi-pole ear pole piece, referring to Figures 1 to 4 , the multi-electrode pole piece comprises:
[0041] The current collector 100 is provided with a coating area 110 or is provided with the coating area 110 and a hollow foil area 120 located at at least one end of the coating area 110;
[0042] An active material layer 200 is applied to the coating area 110;
[0043] A plurality of metal sheets 300 are located on one side of the current collector 100 and are spaced apart along the length direction of the current collector 100. The plurality of metal sheets 300 extend from one side of the current collector 100 and are combined to form a false pole tab when the multiple pole tabs are wound to be used for welding the real pole tab 400.
[0044] Among them, when the current collector 100 is provided with a coating area 110, multiple metal sheets 300 are arranged in the coating area 110 and are welded and connected to the current collector 100; when the current collector 100 is provided with a coating area 110 and an empty foil area 120, multiple metal sheets 300 are arranged in the coating area 110 and / or the empty foil area 120, and are welded and connected to the current collector 100.
[0045] The multi-electrode tab pole piece involved in this embodiment can be a positive pole piece (or cathode pole piece) or a negative pole piece (or anode pole piece), and there is no limitation on this. The multi-electrode tab pole piece includes a current collector 100, an active material layer 200 and a metal sheet 300, wherein the active material layer 200 is coated on the current collector 100. When the multi-electrode tab pole piece is a positive pole piece, the current collector 100 can be made of aluminum foil, and the active material layer 200 can be made of a positive electrode active coating material, such as lithium cobalt oxide, etc.; when the multi-electrode tab pole piece is a negative pole piece, the current collector 100 can be made of copper foil, and the active material layer 200 can be made of a negative electrode active material, such as graphite, etc.
[0046] Specifically, only the coating area 110 is provided on the current collector 100, or the coating area 110 and the empty foil area 120 are provided on the current collector 100 at the same time, the coating area 110 is the area coated with the active material, and correspondingly, the active material layer 200 is coated on the coating area 110, and the empty foil area 120 is the area not coated with the active material. Optionally, the two opposite sides of the current collector 100 are coated with the active material layer 200 in its coating area 110. Among them, when the coating area 110 and the empty foil area 120 are provided on the current collector 100 at the same time, the empty foil area 120 can be one, and the empty foil area 120 is located at one end of the coating area 110; or, there can be two empty foil areas 120, and the two empty foil areas 120 are respectively located at the two ends of the coating area 110.
[0047] There are multiple metal sheets 300, and the multiple metal sheets 300 are located on one side of the current collector 100 and are spaced apart along the length direction of the current collector 100. Among them, the number of metal sheets 300 can be set according to actual conditions, and this embodiment does not limit this. Specifically, there are two or more metal sheets 300. One end of the metal sheet 300 is connected to the current collector 100, and the other end extends from one side of the current collector 100. After the multi-pole ear pole sheet is wound, the width direction of the multi-pole ear pole sheet is used as a reference direction, and the positions of the multiple metal sheets 300 overlap or are adjacent, and then they can be combined to form a false pole ear, and then welded with the real pole ear 400. The false pole ear formed by the combination of multiple metal sheets 300 is connected to the current collector 100 at multiple points, corresponding to the formation of multiple current flow paths, which can improve the current flow capacity to increase the charging speed. The material type of the metal sheet 300 can be set according to actual conditions. Specifically, the metal sheet 300 is preferably made of the same material as the current collector 100 to which it is welded. For example, when the multi-electrode pole piece is a positive pole piece, the current collector 100 is made of aluminum foil, so the metal sheet 300 can be made of aluminum foil; when the multi-electrode pole piece is a negative pole piece, the current collector 100 is made of copper foil, so the metal sheet 300 can be made of copper foil. This is only exemplary and not restrictive. In addition, the metal sheet 300 can also be made of materials such as excellent conductor nickel, copper-plated nickel, and alloy materials.
[0048] Further, when only the coating area 110 is provided on the current collector 100, a plurality of metal sheets 300 are provided in the coating area 110; for example, two metal sheets 300 are provided. Figure 1 As shown, both metal sheets are disposed in the coating area 110 of the current collector 100. When the current collector 100 is provided with both the coating area 110 and the empty foil area 120, the plurality of metal sheets 300 are disposed in the coating area 110 and / or the empty foil area 120. That is, the plurality of metal sheets 300 may be all disposed in the coating area 110 or the empty foil area 120 of the current collector 100, or may be partially disposed in the coating area 110 of the current collector 100 and the other partially disposed in the empty foil area 120 of the current collector 100. For example, when two metal sheets 300 are provided, as shown in FIG. Figure 2 As shown, one metal sheet 300 may be disposed in the coating area 110 of the current collector 100, and another metal sheet 300 may be disposed in the empty foil area 120 of the current collector 100; Figure 3 As shown, the liquid can be two metal sheets 300 are disposed in the coating area 110 of the current collector 100; Figure 4 As shown, two metal sheets 300 can also be arranged in the empty foil area 120 of the current collector 100. In addition, the metal sheet 300 is connected to the current collector 100 by welding, and the connection is stable and easy to operate. The multi-pole tab pole piece of the utility model is provided with a plurality of metal sheets 300 as a false pole tab, and is connected to the current collector 100 by welding. Compared with the current method of manufacturing the false pole tab by die cutting the current collector 100, the manufacturing requirements are low, the difficulty is small, and the operation is simpler.
[0049] It should be noted that the figures only illustrate the positional relationship, connection relationship, etc. among the current collector 100 , the active material layer 200 , and the metal sheet 300 , and do not constitute a limitation on the length, width, and thickness of the same.
[0050] In some embodiments, reference Figure 5 When the metal sheet 300 is disposed in the coating area 110 , the active material layer 200 is configured with a welding groove H adapted to the metal sheet 300 , and the metal sheet 300 is embedded in the welding groove H.
[0051] In this embodiment, the number of welding grooves H in the active material layer 200 is set according to the number of metal sheets 300 required to be set in the coating area 110. For example, when one metal sheet 300 is required to be set in the coating area 110, one welding groove H is correspondingly constructed in the active material layer 200 to accommodate the metal sheet 300; when two metal sheets 300 are required to be set in the coating area 110, two welding grooves H are correspondingly constructed in the active material layer 200, and the two metal sheets 300 are respectively accommodated in the two welding grooves H. Specifically, in actual application, the welding groove H is formed by removing part of the active material of the active material layer 200, so that the current collector 100 at the corresponding position is partially exposed, and the metal sheet 300 is embedded in the welding groove H to be welded with the exposed part of the current collector 100. Among them, the length of the welding groove H is greater than the length of the part of the metal sheet 300 used for welding with the current collector 100, and the width of the welding groove H is greater than the width of the part of the metal sheet 300 used for welding with the current collector 100. Optionally, the active material may be removed by laser cleaning or physical scraping.
[0052] In some embodiments, an insulating structure is provided at the welding position of the current collector 100 for welding the metal sheet 300, and the insulating structure is located on both sides of the current collector 100 and covers the metal sheet 300. In this embodiment, by providing an insulating structure at the welding position of the current collector 100 for welding the metal sheet 300, the insulating structure covers the metal sheet 300 on the side of the current collector 100 where the metal sheet 300 is provided, so as to achieve insulation protection, and avoid the metal sheet 300 from contacting with other pole pieces with opposite polarities to cause an internal short circuit of the battery. It should be noted that when laser cleaning is used to produce a welding groove H in the active material layer 200 on one side of the current collector 100, the active material layer 200 on the other side of the current collector 100 will also be cleaned to form a groove at the position corresponding to the welding groove H. Therefore, at the welding position, an insulating structure is correspondingly arranged on the other side of the current collector 100 where the metal sheet 300 is not arranged. The insulating structure can achieve insulation protection at the groove position to prevent the part of the current collector 100 at the groove position from being exposed and contacting with other pole pieces with opposite polarities to cause an internal short circuit of the battery.
[0053] There are many forms of insulation structure, such as:
[0054] In some embodiments, reference Figures 1 to 4 The insulating structure includes an insulating glue J; when the metal sheet 300 is set in the coating area 110, the insulating glue J covers the metal sheet 300 and is bonded to the active material layer 200; when the metal sheet 300 is set in the empty foil area 120, the insulating glue J covers the metal sheet 300 and is bonded to the current collector 100.
[0055] During manufacturing, the metal sheet 300 is first welded to the current collector 100, and then the insulating glue J is pasted to the metal sheet 300. Specifically, if the metal sheet 300 is set in the coating area 110, the metal sheet 300 is first embedded in the welding groove H of the active material layer 200, and welded to the current collector 100, and then the insulating glue J covers the metal sheet 300 to bond with the metal sheet 300 and the active material layer 200 at the same time. If the metal sheet 300 is set in the empty foil area 120, the metal sheet 300 is welded to the current collector 100, and then the insulating glue J covers the metal sheet 300 to bond with the metal sheet 300 and the current collector 100. In this embodiment, the insulating structure adopts the insulating glue J, which is convenient to obtain and simple to set.
[0056] The insulating glue J has not only an insulating effect, but also has a fixing effect on the metal sheet 300 by bonding to the adjacent structure of the metal sheet 300 (such as the active material layer 200 ), thereby enhancing the structural stability of the metal sheet 300 .
[0057] In addition, the insulating structure may include an insulating layer, and the insulating layer is coated on the side of the metal sheet 300 facing away from the current collector 100. The insulating material used for the insulating layer can be set according to actual conditions and is not limited here.
[0058] In some embodiments, the length of the welding groove H is 5 mm to 30 mm. That is, the length of the welding groove H can be set within the range of 5 mm to 30 mm, for example, the length of the welding groove H can be set to 5 mm, 17.5 mm or 30 mm. Among them, the length of the welding groove H can be set with reference to the length of the portion of the metal sheet 300 used for welding with the current collector 100. Specifically, the length of the welding groove H is slightly larger than the length of the portion of the metal sheet 300 used for welding with the current collector 100. For example, when the length of the portion of the metal sheet 300 used for welding with the current collector 100 is 3 mm, the length of the welding groove H can be set to 5 mm; when the length of the portion of the metal sheet 300 used for welding with the current collector 100 is 15 mm, the length of the welding groove H can be set to 17.5 mm; when the length of the portion of the metal sheet 300 used for welding with the current collector 100 is 28 mm, the length of the welding groove H can be set to 30 mm. The above data are only exemplary and not restrictive.
[0059] In some embodiments, the width of the welding groove H is 5 mm to 30 mm. That is, the width of the welding groove H can be set within the range of 5 mm to 30 mm, for example, the width of the welding groove H can be set to 5 mm, 17.5 mm or 30 mm. Among them, the width of the welding groove H can be set with reference to the width of the metal sheet 300. Specifically, the width of the welding groove H is slightly larger than the width of the metal sheet 300. For example, when the width of the metal sheet 300 is 3 mm, the width of the welding groove H can be set to 5 mm; when the width of the metal sheet 300 is 15 mm, the width of the welding groove H can be set to 17.5 mm; when the width of the metal sheet 300 is 28 mm, the width of the welding groove H can be set to 30 mm. The above data is only exemplary and not restrictive.
[0060] In some embodiments, the length of the welding groove H is 5 mm to 30 mm, and the width of the welding groove H is 5 mm to 30 mm.
[0061] In some embodiments, the thickness of the metal sheet 300 is 3 μm to 100 μm. Specifically, the thickness of the metal sheet 300 can be set within the range of 3 μm to 100 μm. For example, the thickness of the metal sheet 300 can be set to 3 μm, 51.5 μm or 100 μm. Optionally, the thickness of the metal sheet 300 can be set with reference to the thickness specification of the battery cell. For example, when the thickness specification of the battery cell is thin, the thickness of the metal sheet 300 can be set to 3 μm; when the thickness specification of the battery cell is medium, the thickness of the metal sheet 300 can be set to 51.5 μm; when the thickness specification of the battery cell is thick, the thickness of the metal sheet 300 can be set to 100 μm. The above data is exemplary only and not restrictive.
[0062] In some embodiments, the width of the metal sheet 300 is 3 mm to 15 mm. Specifically, the width of the metal sheet 300 can be set within the range of 3 mm to 15 mm. For example, the thickness of the metal sheet 300 can be set to 3 mm, 9 mm, or 15 mm. Optionally, the width of the metal sheet 300 can be set with reference to the width specification of the battery cell. For example, when the width specification of the battery cell is narrow, the width of the metal sheet 300 can be set to 3 mm; when the width specification of the battery cell is medium, the width of the metal sheet 300 can be set to 9 mm; when the width specification of the battery cell is thick, the width of the metal sheet 300 can be set to 15 mm. The above data is exemplary only and not restrictive.
[0063] In some embodiments, the thickness of the metal sheet 300 is 3 μm to 100 μm, and the width of the metal sheet 300 is 3 mm to 15 mm.
[0064] Furthermore, the present invention also provides a battery cell, referring to Figures 6 to 9 , the battery cell comprises:
[0065] The battery cell body is wound;
[0066] The battery cell body comprises a positive electrode sheet and a negative electrode sheet which are stacked and wound on each other;
[0067] Wherein, the positive electrode plate includes the multi-pole ear plate as mentioned above; and / or, the negative electrode plate includes the multi-pole ear plate as mentioned above.
[0068] The specific structure of the multi-electrode ear piece refers to the above-mentioned embodiment. Since the present battery cell adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the technical effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.
[0069] In some embodiments, reference Figures 6 to 9 , along the thickness direction of the battery cell body, the multiple metal sheets 300 in the multi-electrode tabs are overlapped and stacked or staggered. In this embodiment, after the multi-electrode tabs of the positive electrode sheet and / or the negative electrode sheet are wound with the battery cell body, the multiple metal sheets 300 can be overlapped and stacked, or staggered, to form a fake tab. Figure 6 and Figure 7 As shown, when multiple metal sheets 300 overlap and stack, the multiple metal sheets 300 are connected in sequence, and the real tab 400 can be welded to the outermost metal sheet 300; Figure 8 and Fig. 9 As shown, when multiple metal sheets 300 are staggered, the real tab 400 is welded to the multiple metal sheets 300 at the same time. In addition, the multiple metal sheets 300 are staggered, and the occupied thickness spaces overlap each other, thereby reducing the occupied thickness space. It should be noted that, Figure 6 and Figure 8 The two groups of overlapping, stacked or staggered metal sheets 300 shown in the figure include one group of metal sheets 300 of multiple pole tabs included in the positive pole sheet, and the other group of metal sheets 300 of multiple pole tabs included in the negative pole sheet.
[0070] In some embodiments, the plurality of metal sheets 300 in the multi-electrode tab are bent. In this embodiment, optionally, the plurality of metal sheets 300 are bent at 90° relative to the current collector 100. By bending the metal sheets 300, the space occupied by the battery head is reduced, and a compact structure is achieved.
[0071] Furthermore, the embodiment of the utility model also proposes a battery, which includes a housing and a battery cell disposed in the housing, and the battery cell is a battery cell as described in the above embodiment. The specific structure of the battery cell refers to the above embodiment. Since the battery adopts all the technical solutions of all the above embodiments, it has at least all the technical effects brought by the technical solutions of the above embodiments, which will not be described one by one here. Optionally, the battery involved in this embodiment is a lithium battery.
[0072] The above description is only a partial or preferred embodiment of the present invention. Neither the text nor the drawings can limit the scope of protection of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the overall concept of the present invention, or direct / indirect application in other related technical fields are included in the scope of protection of the present invention.
Claims
1. A multi-electrode pole piece, characterized in that: include: A current collector, provided with a coating area or provided with a coating area and a hollow foil area located at at least one end of the coating area; an active material layer, applied to the coating area; A plurality of metal sheets are located on one side of the current collector and are spaced apart along the length direction of the current collector. The plurality of metal sheets extend from one side of the current collector and are combined to form a false pole tab when the multi-pole tab pole sheets are wound to be used for welding a real pole tab; Wherein, when the current collector is provided with the coating area, the multiple metal sheets are provided in the coating area and are welded to the current collector; when the current collector is provided with the coating area and the empty foil area, the multiple metal sheets are provided in the coating area and / or the empty foil area and are welded to the current collector.
2. The multi-electrode pole piece according to claim 1, characterized in that: When the metal sheet is arranged in the coating area, the active material layer is configured with a welding groove matched with the metal sheet, and the metal sheet is embedded in the welding groove.
3. The multi-electrode pole piece according to claim 1 or 2, characterized in that: An insulating structure is provided at a welding position of the current collector for welding the metal sheet. The insulating structure is located on two side surfaces of the current collector and covers the metal sheet.
4. The multi-electrode pole piece according to claim 3, characterized in that: The insulating structure includes insulating glue; When the metal sheet is arranged in the coating area, the insulating glue covers the metal sheet and is bonded to the active material layer; when the metal sheet is arranged in the empty foil area, the insulating glue covers the metal sheet and is bonded to the current collector.
5. The multi-electrode pole piece according to claim 2, characterized in that: The length of the welding groove is 5 mm to 30 mm; and / or, The width of the welding groove is 5 mm to 30 mm.
6. The multi-electrode pole piece according to claim 1, characterized in that: The thickness of the metal sheet is 3 μm to 100 μm; and / or, The width of the metal sheet is 3 mm to 15 mm.
7. A battery cell, characterized in that: include: The battery cell body is wound; The battery cell body comprises a positive electrode sheet and a negative electrode sheet which are stacked and wound on each other; Wherein, the positive electrode plate comprises the multi-pole ear plate as described in any one of claims 1-6; and / or, the negative electrode plate comprises the multi-pole ear plate as described in any one of claims 1-6.
8. The battery cell according to claim 7, characterized in that: Along the thickness direction of the battery cell body, a plurality of the metal sheets in the multi-electrode tab pole pieces are overlapped and stacked or staggered.
9. The battery cell according to claim 7 or 8, characterized in that: The plurality of metal sheets in the multi-electrode tab pole piece are bent.
10. A battery, characterized in that: The invention comprises a shell and a battery cell arranged in the shell, wherein the battery cell is the battery cell as claimed in any one of claims 7 to 9.