Battery cell pole piece, battery cell, battery, battery pack and electric equipment

Abstract

The utility model discloses a battery cell pole piece, a battery cell, a battery, a battery pack and electric equipment, the battery cell pole piece comprises a base material, the base material comprises a tab area and a coating area, and the tab area is located on one side of the coating area along a first direction; and the grafting piece covers at least partial area of at least one surface of the tab area from the end part of the battery cell pole piece along the first direction to the coating area. According to the scheme, the grafting piece covers at least part of the area of the at least one surface of the tab area from the end part of the battery cell pole piece in the first direction to the coating area, and forms the tab with the tab area, so that the overcurrent area of the tab can be increased, the internal resistance of the tab can be reduced, the overcurrent capacity of the tab can be improved, and the service life of the tab is prolonged. The problem that the temperature rise of the tabs is too high during fast charging is effectively solved.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and more particularly to a core electrode sheet, a core, a battery, a battery pack, and an electrical device using the same. Background Art

[0002] With the accelerating pace of life, people hope that electronic products can be charged in a shorter time to achieve higher usage frequencies and better practical experiences, which places higher requirements on the fast charging performance of batteries.

[0003] However, in the related art, the tab of the core electrode sheet in the battery is generally a single-layer foil material with a relatively thin thickness and a small current-carrying area, resulting in an excessive temperature rise of the tab during fast charging of the battery, and further causing the fast charging performance of the battery to fail to meet market requirements, and affecting the service life and safety performance of the battery. Summary of the Utility Model

[0004] A series of simplified concepts are introduced in the Summary of the Utility Model section, which will be further described in detail in the Detailed Implementation section. The Summary of the Utility Model section of the present utility model does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0005] In view of the existing problems, on the one hand, the present utility model provides a core electrode sheet, comprising:

[0006] A substrate, including a tab region and a coating region, wherein the tab region is located on one side of the coating region along a first direction;

[0007] A grafting member, covering at least a partial region of at least one surface of the tab region from an end of the core electrode sheet along the first direction towards the coating region.

[0008] Exemplarily, the grafting member is welded to the tab region.

[0009] Exemplarily, the grafting member covers at least a partial region of one surface of the tab region and is welded to the tab region through at least one weld seam; or,

[0010] The grafting member has an overall U-shaped structure covering at least a partial region of the end of the core electrode sheet along the first direction and two surfaces of the tab region, and is welded to the tab region through at least one weld seam;

[0011] Wherein, the weld seam extends along a second direction, and the second direction is perpendicular to the first direction.

[0012] Exemplarily, the grafting member is welded and connected to the tab region through a plurality of weld seams spaced along the first direction.

[0013] Exemplarily, the width of the weld seam along the first direction is greater than or equal to 1 mm.

[0014] Exemplarily, the weld seam is made by an ultrasonic roll welding process.

[0015] Exemplarily, a coating is further included, and the coating covers at least one surface of the coating area of the substrate.

[0016] Exemplarily, the thickness of the grafting member on the surface of the tab region is less than or equal to the thickness of the coating on the surface of the coating area on the same side.

[0017] Exemplarily, the cell electrode tab is a positive electrode tab, the substrate is a smooth aluminum foil, and the coating is a positive active material coating; or,

[0018] the cell electrode tab is a negative electrode tab, the substrate is a smooth copper foil, and the coating is a negative active material coating.

[0019] Exemplarily, when the cell electrode tab is the positive electrode tab, the grafting member is a smooth aluminum foil;

[0020] when the cell electrode tab is the negative electrode tab, the grafting member is a smooth copper foil.

[0021] On the other hand, the present application provides a battery cell, including a positive electrode tab, a negative electrode tab, and a separator layer, the separator layer is disposed between the positive electrode tab and the negative electrode tab, wherein at least one of the positive electrode tab and the negative electrode tab includes the above-mentioned cell electrode tab.

[0022] Exemplarily, the positive electrode tab, the negative electrode tab, and the separator layer are wound to form a wound battery cell; or,

[0023] the positive electrode tab, the negative electrode tab, and the separator layer are stacked to form a stacked battery cell.

[0024] On the other hand, the present application provides a battery, including a housing, a cover plate, and the above-mentioned battery cell, the housing and the cover plate enclose an accommodation space, and the battery cell is accommodated in the accommodation space.

[0025] On the other hand, the present application provides a battery pack, including the above-mentioned battery.

[0026] On the other hand, the present application provides an electrical device, including the above-mentioned battery, or including the above-mentioned battery pack.

[0027] According to the cell pole piece, cell, battery, battery pack and electrical equipment of the present utility model, the grafting piece in the cell pole piece covers at least a part of at least one surface of the tab area from the end of the cell pole piece along the first direction towards the coating area, and forms a tab with the tab area, thereby being able to reduce the internal resistance of the tab and improve the overcurrent capacity of the tab, effectively improving the problem of excessive temperature rise of the tab during fast charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] By describing the embodiments of the present application in more detail in conjunction with the drawings, the above and other objects, features and advantages of the present application will become more obvious. The drawings are used to provide a further understanding of the embodiments of the present application, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation to the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0029] Figure 1A FIG. shows a schematic structural diagram of a cell pole piece in the related art;

[0030] Figure 1B FIG. shows a schematic structural diagram of a wound cell formed by winding the cell pole piece in the related art;

[0031] Figure 2 FIG. shows a schematic structural diagram of a cell pole piece according to a specific embodiment of the present application;

[0032] Figure 3 FIG. shows a Figure 2 view of the cell pole piece in the present application along the A-A direction;

[0033] Figure 4 FIG. shows a Figure 3 region enlarged schematic diagram of the present application;

[0034] Figure 5 FIG. shows a schematic structural diagram of a cell pole piece according to another specific embodiment of the present application;

[0035] Figure 6 FIG. shows a Figure 5 view of the cell pole piece in the present application along the A-A direction;

[0036] Figure 7 FIG. shows a Figure 6 region enlarged schematic diagram of the present application

[0037] Figure 8 FIG. shows a schematic structural diagram of a wound cell formed by winding the cell pole piece according to a specific embodiment of the present application.

[0038] Reference numerals:

[0039] 110 - Substrate; 120 - Coating; 210 - Substrate;

[0040] 220 - Grafting part; 230 - Coating; 240 - Weld seam. Detailed implementation manners

[0041] In the following description, numerous specific details are given to provide a more thorough understanding of the present application. However, it will be apparent to those skilled in the art that the present application may be practiced without one or more of these details. In other instances, some well - known technical features are not described to avoid obscuring the present application.

[0042] It should be understood that the present application can be implemented in different forms and should not be construed as limited to the embodiments presented herein. On the contrary, these embodiments are provided to make the disclosure thorough and complete, and to fully convey the scope of the present application to those skilled in the art. In the drawings, the dimensions and relative dimensions of layers and regions may be exaggerated for clarity. Like reference numerals throughout the drawings denote like elements.

[0043] It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or part from another element, component, region, layer, or part. Thus, without departing from the teachings of the present application, the first element, component, region, layer, or part discussed below may be referred to as the second element, component, region, layer, or part.

[0044] Spatial relationship terms such as "under", "below", "lower", "beneath", "above", "upper", etc. are used herein for convenience in describing the relationship of one element or feature shown in the figures to other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relationship terms are intended to also include different orientations of the device in use and operation.

[0045] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present application. As used herein, the singular forms "a", "an", and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. As used herein, the term "and / or" includes any and all combinations of the related listed items.

[0046] In the related art, as Figure 1A and Figure 1B shown, the electrode tab of the battery cell in a battery generally includes a base material 110 and a coating 120. The base material 110 includes a coating area and a tab area. The tab area is located on one side of the coating area along the first direction. The coating 120 covers both surfaces of the coating area of the base material. The tab area serves as the tab of the electrode tab of the battery cell. That is, the tab of the electrode tab in the related art is a single-layer base material with a relatively thin thickness and a small current-carrying area of the tab, resulting in too high a temperature rise of the tab during fast charging of the battery, and further causing the fast charging performance of the battery to fail to meet the market demand, and affecting the service life and safety performance of the battery.

[0047] It should be noted that Figure 1A and Figure 1B although the tab areas in the electrode tabs shown in Figure 1B are located on both sides of the coating area along the first direction, this is an intermediate product produced to improve production efficiency. In the electrode tab of the battery cell actually used in the battery, the tab area is located on one side of the coating area along the first direction. Taking the example of winding the electrode tab of the battery cell into a wound battery cell as shown in Figure 1B , the electrode tab of the battery cell is wound into a wound battery cell along the direction perpendicular to the first direction. After winding, the wound battery cell will be cut to form two battery cells symmetrically arranged along the first direction. The tab area of the electrode tab in each battery cell is located on one side of the coating area along the first direction.

[0048] In view of the existence of the above technical problems, the present utility model provides an electrode tab of a battery cell, a battery cell, a battery, a battery pack and an electrical device using the same to solve the above problems.

[0049] Refer to Figures 2 to 7 for an exemplary description of the electrode tab of a battery cell according to a specific embodiment of the present application. As Figures 2 to 7 shown, the electrode tab of the present application includes a base material (also referred to as a current collector) 210 and a grafting member 220, wherein: the base material 210 includes a tab area and a coating area, and the tab area is located on one side of the coating area along the first direction; the grafting member 220 covers at least a partial area of at least one surface of the tab area from the end of the electrode tab along the first direction towards the coating area. Among them, the tab area of the base material 210 and the grafting member 220 together constitute the tab of the electrode tab of the battery cell. Exemplarily, the first direction may be the length direction or the width direction of the electrode tab of the battery cell, and the present application does not limit this.

[0050] It should be noted that although Figure 2 and Figure 5The structure of the electrode tab of the battery cell shown has the tab regions located on both sides of the coating region along the first direction. However, this is an intermediate product produced to improve production efficiency. In the electrode tab of the battery cell actually used in the battery, the tab region is located on one side of the coating region along the first direction, which is equivalent to cutting the electrode tab of the battery cell obtained in manufacturing, such as Figure 2 and Figure 5 shown, into two symmetric electrode tabs along the first direction. In each electrode tab of the battery cell, the tab region is located on one side of the coating region along the first direction; or, after manufacturing a wound battery cell such as Figure 8 shown, cutting the electrode tab of the battery cell into two symmetric battery cells along the first direction. In the electrode tab of each battery cell, the tab region is located on one side of the coating region along the first direction.

[0051] In the above solution, the tab of the electrode tab of the present application is equivalent to a grafting member specially provided on the tab region of the substrate. The outer end portion of the tab along the first direction is connected to the cover plate of the battery to achieve current flow. The grafting member covers at least a partial region of at least one surface of the tab region from the end portion of the electrode tab along the first direction toward the coating region, which can increase the contact area connected to the cover plate on the basis of the original tab region, that is, can increase the current-carrying area of the tab, and further can reduce the internal resistance of the tab and improve the current-carrying capacity of the tab, effectively improving the problem of excessive temperature rise of the tab during fast charging.

[0052] In one example, as Figures 2 to 7 shown, the electrode tab of the present application further includes a coating 230, and the coating 230 covers at least one surface of the coating region of the substrate 210. Preferably, the coating 230 covers both surfaces of the coating region.

[0053] In one example, the electrode tab can be a positive electrode tab or a negative electrode tab. When the electrode tab is a positive electrode tab, the substrate 210 is a smooth aluminum foil, and the coating 230 is a positive active material coating; when the electrode tab is a negative electrode tab, the substrate 210 is a bright copper foil, and the coating 230 is a negative active material coating. Exemplarily, the substrate 210 can also be other suitable materials, and the present application does not limit this.

[0054] Specifically, the material of the positive electrode active material coating can be a lithium-containing phosphate with an olivine structure, a lithium transition metal oxide, and their respective modified compounds. The lithium-containing phosphate with an olivine structure can include, but is not limited to, at least one of lithium iron phosphate (such as LiFePO4 (which can also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon, but is not limited to the above examples. The material of the negative electrode active material coating can be at least one of artificial graphite, natural graphite, mesocarbon microbeads, hard carbon, soft carbon, silicon, silicon oxide, silicon carbide, and silicon alloy, but is not limited to the above examples.

[0055] In one example, when the cell electrode is a positive electrode, the grafting member 220 is a smooth aluminum foil; when the cell electrode is a negative electrode, the grafting member 220 is a smooth copper foil. Preferably, the material of the grafting member 220 is the same as the material of the base material of the cell electrode. Exemplarily, the material of the grafting member can also be any other suitable material, and the present application does not limit this.

[0056] In one example, the grafting member 220 is welded to the tab area.

[0057] In one example, as Figures 2 to 4 shown, the grafting member 220 is integrally formed in a U-shaped structure that covers at least part of the end of the cell electrode along the first direction and covers at least part of the two surfaces of the tab area, and is welded to the tab area through at least one weld 240. Exemplarily, the grafting member 220 should cover at least part of each of the two surfaces of the tab area. Exemplarily, since the grafting member 220 is an integrally formed U-shaped structure, it is naturally fastened to the end of the cell electrode, so that at least one weld is required to firmly weld the grafting member 220 to the tab area. Exemplarily, the weld should be close to one end of the grafting member 220 of the U-shaped structure away from the cell electrode.

[0058] In another example, as Figures 5 to 7 shown, the grafting member 220 covers at least part of one surface of the tab area and is welded to the tab area through at least one weld 240. Exemplarily, the grafting member 220 covers at least part of one surface of the tab area from the end of the cell electrode along the first direction towards the coating area.

[0059] In one example, the grafting member 220 is welded and connected to the tab region through a plurality of welds 240 spaced along a first direction. Among them, when the grafting member 220 has a U-shaped structure as a whole to cover the end of the battery cell electrode along the first direction and at least a partial area of the two surfaces of the tab region, although the grafting member 220 can be firmly connected to the tab region only through one weld 240, the present application does not specifically limit the number of welds 240; when the grafting member 220 covers at least a partial area of one surface of the tab region, since the grafting member 220 only covers at least a partial area of one surface of the tab region, the grafting member 220 is not naturally firmly connected to the end of the battery cell electrode. If there is only one weld 240, problems such as curling and wrinkling are likely to occur in the region of the grafting member 220 far from the weld 240. Preferably, a plurality of welds 240 are required to firmly weld and connect the grafting member 220 to the tab region.

[0060] In one example, whether the grafting member 220 only covers at least a partial area of one surface of the tab region or the grafting member 220 covers at least a partial area of the two surfaces of the tab region, the grafting member 220 extends from the end of the battery cell electrode along the first direction toward the coating region to cover the tab region. In the battery where the battery cell electrode is located, the end of the battery cell electrode along the first direction where the tab region is formed will be connected to an external circuit. By welding and connecting the grafting member 220 to this end to form a tab, the contact area between the end of the tab and the external circuit can be effectively increased, thereby reducing the internal resistance of the tab and increasing the current-carrying area of the tab, effectively improving the problem of excessive temperature rise of the tab during fast charging of the battery.

[0061] In one example, the above-mentioned welds 240 all extend along a second direction, and the second direction is perpendicular to the first direction. For example, if the first direction is the length direction of the battery cell electrode, then the second direction is the width direction of the battery cell electrode; if the first direction is the width direction of the battery cell electrode, then the second direction is the length direction of the battery cell electrode.

[0062] In one example, the width of the above-mentioned weld 240 along the first direction is greater than or equal to 1 mm. For example, the width of the weld 240 along the first direction can be 1 mm, 2 mm, 4 mm, 5.5 mm, etc. Preferably, the width range of the weld 240 along the first direction is 2 mm - 5 mm. For example, it is 2 mm, 3 mm, 3.5 mm, 4 mm, 5 mm, etc.

[0063] In one example, the above-mentioned welds 240 are made by an ultrasonic roll welding process. In other embodiments, the welds 240 can also be made by various conventional welding processes in the art, and the present application does not limit this.

[0064] In one example, the thickness of the grafting member 220 on the surface of the tab area should be less than or equal to the thickness of the coating 230 on the surface of the coating area on the same side, so as to prevent the tab of the battery cell from being unable to be processed into a battery cell due to the thickness of the grafting member 220 being greater than that of the coating 230. For example, it cannot be wound into a wound battery cell.

[0065] Thus, the introduction of the structure of the tab of the battery cell of the present utility model is completed. For a complete tab of the battery cell, there may also be other component structures, which will not be elaborated one by one here.

[0066] In summary, the grafting member in the tab of the battery cell of the present utility model covers at least a partial area of at least one surface of the tab area from the end of the tab of the battery cell along the first direction towards the coating area, and forms a tab with the tab area. Furthermore, it can reduce the internal resistance of the tab and improve the overcurrent capacity of the tab, effectively improving the problem of excessive temperature rise of the tab during fast charging, enhancing the safety of the battery where the tab of the battery cell is located, and extending the service life of the battery.

[0067] The embodiment of the present application further provides a battery cell, which includes a positive electrode tab, a negative electrode tab, and a separator. Among them, at least one of the positive electrode tab and the negative electrode tab includes the above-mentioned tab of the battery cell. The separator is disposed between the positive electrode tab and the negative electrode tab to prevent the positive electrode tab and the negative electrode tab from directly contacting and causing a short circuit. Exemplarily, pores for ion movement are formed in the separator, as well as in the coating of the positive electrode tab and the coating of the negative electrode tab.

[0068] In one example, as Figure 8 shown, the positive electrode tab, the negative electrode tab, and the separator are wound into a wound battery cell. More specifically, the positive electrode tab, the negative electrode tab, and the separator are wound into a wound battery cell along a direction perpendicular to the first direction; or, the positive electrode tab, the negative electrode tab, and the separator are stacked into a stacked battery cell. It should be noted that Figure 8 what is shown is an intermediate product of a wound battery cell formed to improve efficiency. After manufacturing the wound battery cell as Figure 8 shown, the tab of the battery cell will also be cut into two battery cells symmetrical along the first direction, and the tab area in the tab of the battery cell of each battery cell is located on one side of the coating area along the first direction. Exemplarily, the tabs of the positive electrode tab and the negative electrode tab in the wound battery cell and the stacked battery cell are located on the same side. Exemplarily, before winding or stacking the positive electrode tab, the negative electrode tab, and the separator, it further includes a step of die-cutting the tabs of the positive electrode tab and the negative electrode tab to remove part of the tabs so that the shape of the tabs meets the requirements. Exemplarily, before winding or stacking the positive electrode tab, the negative electrode tab, and the separator, it further includes a step of slitting and processing the positive electrode tab, the negative electrode tab, and the separator.

[0069] In one example, taking the case where the positive electrode tab, the negative electrode tab and the separator are wound to form a wound battery cell, and the negative electrode tab is the above-mentioned battery cell tab, during the manufacturing process, a conventional negative electrode tab is first provided, that is, a negative electrode tab including only a substrate and a coating is provided, and a grafting member is also provided; then the grafting member is welded to the tab area of the substrate; finally, the welded negative electrode tab is wound or laminated with the positive electrode tab and the separator.

[0070] In one example, the shape of the battery cell can specifically be a short battery cell or a long battery cell with a relatively thin thickness, or a rectangular block-shaped battery cell with a slightly thicker thickness. The rectangular block-shaped battery cell can specifically be, such as but not limited to, a square aluminum shell battery cell, etc. The shape of the battery cell can also be a cylindrical battery cell.

[0071] Thus, the introduction of the structure of the battery cell of the present utility model is completed. For a complete battery cell, there may be other component structures, which will not be elaborated one by one here.

[0072] In summary, at least one of the positive electrode tab and the negative electrode tab of the battery cell of the present utility model includes the above-mentioned battery cell tab. The grafting member in the battery cell tab covers at least a part of at least one surface of the tab area from the end of the battery cell tab along the first direction towards the coating area, and forms a tab with the tab area, thereby being able to reduce the internal resistance of the tab and improve the over-current capacity of the tab, effectively improving the problem of excessive temperature rise of the tab during fast charging, improving the safety of the battery where the battery cell is located, and extending the service life of the battery.

[0073] The embodiment of the present application also provides a battery, including a housing, a cover plate and the above-mentioned battery cell. The housing and the cover plate enclose an accommodation space, and the battery cell is accommodated in the accommodation space.

[0074] In one example, the tab in the battery cell tab of the battery is generally connected to the cover plate to achieve electrical connection with an external circuit. However, the tab in the battery cell tab of the present application is jointly composed of the tab area of the original substrate and the welded grafting member, which can effectively increase the contact area between the tab and the cover plate, thereby being able to reduce the internal resistance of the tab and improve the over-current capacity of the tab, effectively improving the problem of excessive temperature rise of the tab during fast charging, improving the safety of the battery, and extending the service life of the battery.

[0075] In one example, multiple battery cells are provided in the battery, and an exhaust channel is provided between any adjacent layers of battery cells. Exemplarily, the exhaust channel can be used to prevent gas inside the battery from accumulating between the battery cells, thereby being able to avoid safety problems such as the battery swelling, bursting or even exploding. Exemplarily, the exhaust channel is provided in a cross beam or a longitudinal beam between adjacent layers of battery cells.

[0076] In one example, a cold plate is further provided at the top and / or bottom of the battery cell. The cold plate is bonded to the battery cell through a thermally conductive structural adhesive and is used to control the temperature of the battery cell.

[0077] Thus, the introduction of the structure of the battery of the present utility model is completed. For a complete battery, there may be other component structures, which will not be elaborated one by one here.

[0078] The embodiment of the present application further provides a battery pack, including the above-mentioned battery. Exemplarily, for a complete battery pack, there may be other component structures, which will not be elaborated one by one here.

[0079] The embodiment of the present application further provides an electrical device, including the above-mentioned battery, or including the above-mentioned battery pack. The electrical device includes electric vehicles, hybrid vehicles, industrial devices, etc., all of which are within the protection scope of the present utility model.

[0080] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application. Those of ordinary skill in the art can make various changes and modifications therein without departing from the scope and spirit of the present application. All such changes and modifications are intended to be included within the scope of the present application as claimed by the appended claims.

[0081] In the specification provided herein, a large number of specific details are set forth. However, it can be understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures, and technologies have not been shown in detail so as not to obscure the understanding of this specification.

[0082] Similarly, it should be understood that, in order to streamline the present application and assist in understanding one or more of the various inventive aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be construed as reflecting the intention that the claimed present application requires more features than those expressly recited in each claim. Rather, as reflected by the corresponding claims, the inventive point lies in that the corresponding technical problems can be solved by features less than all the features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into the detailed description, where each claim itself serves as a separate embodiment of the present application.

[0083] Those skilled in the art will appreciate that, except where features are mutually exclusive, any combination can be employed of all the features disclosed in this specification (including the accompanying claims, abstract and drawings), as well as of all the processes or units of any method or device so disclosed. Each feature disclosed in this specification (including the accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

[0084] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not others, combinations of features of different embodiments are meant to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0085] It should be noted that the above embodiments illustrate rather than limit the application, and that those skilled in the art can design alternative embodiments without departing from the scope of the appended claims.

Claims

1. A battery cell electrode, characterized in that: include: A substrate, comprising a tab region and a coating region, wherein the tab region is located on one side of the coating region along a first direction; A grafting piece covers at least a portion of at least one surface of the tab region from an end of the cell electrode along the first direction toward the coating region.

2. The battery cell electrode according to claim 1, characterized in that: The grafting piece is connected to the tab region by welding.

3. The battery cell electrode according to claim 2, characterized in that: The grafting piece covers at least a portion of a surface of the tab region and is welded to the tab region through at least one weld; or, The grafting piece is in a U-shaped structure as a whole, covers the end of the battery cell electrode along the first direction and at least part of the two surfaces of the pole ear area, and is welded to the pole ear area through at least one weld; Wherein, the weld extends along a second direction, and the second direction is perpendicular to the first direction.

4. The battery cell electrode according to claim 3, characterized in that: The grafting piece is welded to the tab region through a plurality of welds spaced apart along the first direction.

5. The battery cell electrode according to claim 3, characterized in that: The width of the weld along the first direction is greater than or equal to 1 mm.

6. The battery cell electrode according to claim 3, characterized in that: The weld is made by an ultrasonic roller welding process.

7. The battery cell electrode according to claim 1, characterized in that: Also included is a coating covering at least one surface of the coating region of the substrate.

8. The battery cell electrode according to claim 7, characterized in that: The thickness of the graft on the surface of the tab region is less than or equal to the thickness of the coating on the surface of the coating region located on the same side.

9. The battery cell electrode according to claim 7, characterized in that: The battery cell pole piece is a positive pole piece, the substrate is a smooth aluminum foil, and the coating is a positive electrode active material coating; or, The battery cell pole piece is a negative pole piece, the substrate is a smooth copper foil, and the coating is a negative electrode active material coating.

10. The battery cell electrode according to claim 9, characterized in that: When the battery cell electrode is the positive electrode, the grafting member is a smooth aluminum foil; When the battery cell electrode is the negative electrode, the grafting member is a smooth copper foil.

11. A battery cell, characterized in that: It comprises a positive electrode sheet, a negative electrode sheet and an isolation layer, wherein the isolation layer is arranged between the positive electrode sheet and the negative electrode sheet, wherein at least one of the positive electrode sheet and the negative electrode sheet comprises the battery cell sheet according to any one of claims 1-10.

12. The battery cell according to claim 11, characterized in that: The positive electrode sheet, the negative electrode sheet and the isolation layer are wound to form a wound battery cell; or, The positive electrode sheet, the negative electrode sheet and the isolation layer stack are arranged to form a stacked battery cell.

13. A battery, characterized in that: The invention comprises a shell, a cover plate and the battery cell according to any one of claims 11 to 12, wherein the shell and the cover plate enclose a containing space, and the battery cell is arranged in the containing space.

14. A battery pack, characterized in that: Comprising the battery of claim 13.

15. An electrical equipment, characterized in that: Includes the battery as claimed in claim 13, or includes the battery pack as claimed in claim 14.

Images