Electrode sheets and battery cells

Abstract

This application relates to the field of battery technology, providing an electrode sheet and a battery cell. The electrode sheet includes a current collector and a tab. The current collector is the main component of the tab, and the tab is connected to the current collector. The tab can be connected to an external structure to conduct electricity. Both the tab and the current collector are thin sheet structures. When the electrode sheet passes through a conveyor roller and the moving direction of the electrode sheet switches between horizontal and vertical directions, the tab will bend along the arc-shaped surface of the conveyor roller. The tab separator groove can divide the tab into at least two parts, which can reduce the internal stress of the tab during bending deformation and prevent the tab from tearing when bending and deforming through the conveyor roller. This can result in a higher yield rate during the preparation of the electrode sheet of this application and reduce the preparation cost of the electrode sheet.

Description

Technical Field

[0001] This application relates to an electrode and a battery cell, belonging to the field of battery technology. Background Technology

[0002] The electrode of a battery cell includes a current collector and a tab. The electrode is a thin sheet structure. During electrode fabrication, relatively long electrode blanks need to be cut to form the electrode. Specifically, laser cutting can be used to cut the electrode blanks. To improve electrode fabrication efficiency, automated equipment is used to process the electrode blanks. This automated equipment includes conveyor rollers, on which the electrode blanks move to various workstations, such as the laser cutting station.

[0003] Currently, when the electrode moves on the conveyor roller, the layout of the automated production line may cause the horizontal movement to be converted into vertical movement. This can cause the tabs on the electrode material to bend, resulting in tearing and damage to the tabs on the electrode. Utility Model Content

[0004] This application provides an electrode sheet and a battery cell to solve the problem in the related art that the electrode tabs are easily torn and damaged when the electrode sheet passes through the conveyor roller.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] In a first aspect, this application provides an electrode sheet, comprising:

[0007] current collector;

[0008] The electrode tab is connected at one end to the current collector.

[0009] The electrode tab has a dividing groove that extends through the electrode tab along its thickness direction. One end of the dividing groove extends to the side of the electrode tab, and the other end extends toward the current collector. The dividing groove divides the electrode tab into at least two parts.

[0010] In some embodiments, one end of the separator extends to the side of the tab away from the current collector.

[0011] In some embodiments, the electrode tab includes a plurality of sub-electrode tabs, the partition groove is located between adjacent sub-electrode tabs, and the bottom wall of the partition groove is spaced from the current collector to connect adjacent sub-electrode tabs.

[0012] In some embodiments, the dividing groove has an opening located on the side of the tab, and the width of the dividing groove gradually decreases along the direction from the opening to the bottom wall of the dividing groove.

[0013] In some embodiments, the sidewalls of the partition groove are inclined or curved.

[0014] In some embodiments, the dividing groove is located in the middle of the tab.

[0015] In some embodiments, the number of the partition grooves is multiple, and the multiple partition grooves are evenly spaced along the length direction of the current collector.

[0016] In some embodiments, the direction from the tab to the current collector is perpendicular to the length direction of the current collector.

[0017] In some embodiments, the number of electrodes is two, and the two electrodes are spaced apart on the same side of the current collector along the length direction of the current collector.

[0018] Secondly, based on the aforementioned electrode, this application also provides a battery cell including the aforementioned electrode.

[0019] In the electrode sheet provided in this application, the current collector is the main component of the tab, and the tab is connected to the current collector. The tab can also be connected to an external structure to conduct electricity. Both the tab and the current collector are thin sheet structures. When the electrode sheet passes through the conveyor roller and the moving direction of the electrode sheet switches between horizontal and vertical directions, the tab will bend along the arc surface of the conveyor roller. The tab dividing groove can divide the tab into at least two parts, which can reduce the internal stress of the tab during the bending deformation process and prevent the tab from tearing when bending and deforming through the conveyor roller. This can result in a higher yield rate during the preparation of the electrode sheet of this application and reduce the preparation cost of the electrode sheet.

[0020] The battery cell provided in this application, including the aforementioned electrode, results in a higher yield rate during battery cell manufacturing and reduces battery cell manufacturing costs. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the electrode sheet provided in an embodiment of this application;

[0023] Figure 2 A schematic diagram showing the electrode sheet being transported by a conveyor roller according to an embodiment of this application;

[0024] Figure 3 A schematic diagram showing that the electrode provided in the embodiments of this application includes two tabs;

[0025] Figure 4 This is a schematic diagram showing that there are multiple electrodes provided in the embodiments of this application.

[0026] Explanation of reference numerals in the attached figures:

[0027] 100-current collector;

[0028] 200 - tab; 210 - separator groove; 211 - groove opening; 220 - sub-tab part;

[0029] 300 - Conveyor Roller. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0031] The electrode of a battery cell includes a current collector and a tab. The electrode is a thin sheet structure. During electrode fabrication, relatively long electrode blanks need to be cut to form the electrode. Specifically, laser cutting can be used to cut the electrode blanks. To improve electrode fabrication efficiency, automated equipment is used to process the electrode blanks. This automated equipment includes conveyor rollers, on which the electrode blanks move to various workstations, such as the laser cutting station.

[0032] Currently, when the electrode moves on the conveyor roller, the layout of the automated production line may cause the horizontal movement to be converted into vertical movement. This can cause the tabs on the electrode material to bend, resulting in tearing and damage to the tabs on the electrode.

[0033] In the electrode sheet proposed in this application, the current collector is the main component of the tab, and the tab is connected to the current collector. The tab can also be connected to an external structure to conduct electricity. Both the tab and the current collector are thin sheet structures. When the electrode sheet passes through the conveyor roller and the moving direction of the electrode sheet switches between horizontal and vertical directions, the tab will bend along the arc surface of the conveyor roller. The tab partition groove can divide the tab into at least two parts, which can reduce the internal stress of the tab during the bending deformation process and prevent the tab from tearing when bending and deforming through the conveyor roller. This can result in a higher yield rate during the preparation of the electrode sheet of this application and reduce the preparation cost of the electrode sheet.

[0034] The battery cell proposed in this application, including the aforementioned electrode, results in a higher yield rate during battery cell manufacturing and reduces battery cell manufacturing costs.

[0035] The contents of this application will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can have a clearer and more detailed understanding of the contents of this application.

[0036] This application proposes an electrode, with reference to Figures 1 to 2 As shown, it includes a current collector 100 and a tab 200. This electrode can be used in a battery cell, which may include multiple electrodes, with adjacent electrodes having opposite polarities.

[0037] The current collector 100 is the basic component of the electrode sheet of this application. The current collector 100 can provide a mounting base for at least some other components of the electrode sheet, thereby stabilizing the electrode sheet structure. Specifically, the current collector 100 has a thin sheet structure, making its thickness much smaller than its length and width. The current collector 100 can be made of metallic materials, specifically aluminum foil or copper foil.

[0038] The tab 200 is connected to one end of the current collector 100 and is used for electrical connection with the external structural components of the electrode. The tab 200 can also be in the form of a thin sheet structure, and the tab 200 is also made of metal. Specifically, the tab 200 can be made of pure metal materials such as aluminum, copper, and nickel, or related alloy materials; this application does not impose any restrictions on this.

[0039] The tab 200 is disposed on one end side of the current collector 100, and the direction from the tab 200 to the current collector 100 is a first direction, which is perpendicular to the thickness direction of the current collector 100. Specifically, the first direction can be the width direction of the current collector 100, i.e. Figure 1 In the Y direction, the tab 200 is located at any end of the current collector 100 in its width direction. In this way, the tab 200 will not occupy the surface area of ​​the current collector 100 on both sides in the thickness direction of the current collector 100, which can make the area of ​​the current collector 100 that can be coated with the dressing layer larger.

[0040] In addition, the first direction can also be the length direction of the current collector 100, that is... Figure 1 In the X direction, the tab 200 is located at any end of the current collector 100 along its length, so that the tab 200 does not occupy the surface area of ​​the current collector 100 on both sides in the thickness direction of the current collector 100, which allows for a larger area on the current collector 100 that can be coated with a dressing layer.

[0041] The tab 200 has a dividing groove 210 that extends through the tab 200 along its thickness direction, such that the dividing groove 210 has openings on both sides of the tab 200 in its thickness direction. One end of the dividing groove 210 also extends to the side of the tab 200 away from the current collector 100, so that the side of the tab 200 can form the opening 211 of the dividing groove 210. In this way, the dividing groove 210 can divide the tab 200 into at least two parts located on both sides of the dividing groove 210, so that the tab 200 has a disconnected structure.

[0042] When the electrode is manufactured by automated equipment, the conveyor roller 300 of the automated equipment can transport the electrode along the length of the current collector 100, that is, along... Figure 2 The electrode 200 moves in the X direction. Correspondingly, the tab 200 slides on the conveyor roller 300. When the electrode changes direction as it passes through the conveyor roller 300, switching between horizontal and vertical directions, the tab 200 moves accordingly around the conveyor roller 300, causing it to bend. Dividing the tab 200 into at least two parts by the dividing groove 210 allows each part of the tab 200 to move independently around the conveyor roller 300 as it moves. This allows each part of the tab 200 to bend and deform independently, preventing interaction between them and reducing internal stress. This prevents tearing and damage when the tab 200 changes direction while moving around the conveyor roller 300, maintaining structural integrity and ultimately improving the yield of the electrode fabrication in this application.

[0043] In the electrode sheet proposed in this application, the current collector 100 is the main component of the tab 200. The tab 200 is connected to the current collector 100 and can be connected to an external structure to conduct electricity. Both the tab 200 and the current collector 100 are thin sheet structures. When the electrode sheet passes through the conveyor roller 300 and the moving direction of the electrode sheet switches between horizontal and vertical directions, the tab 200 will bend along the arc-shaped surface of the conveyor roller 300. The tab 200 partition groove 210 can divide the tab 200 into at least two parts, which can reduce the internal stress of the tab 200 during the bending deformation process and prevent the tab 200 from tearing when bending and deforming through the conveyor roller 300. This can result in a higher yield rate of the electrode sheet during the preparation of this application and reduce the preparation cost of the electrode sheet.

[0044] In some implementations, reference Figure 1 and Figure 3As shown, one end of the partition groove 210 of the tab 200 of this application can extend to the side of the tab 200 away from the electrode plate, and a groove 211 is formed on the surface of the tab 200 away from the electrode plate. In this way, the partition groove 210 of the tab 200 extends along the direction from the tab 200 to the current collector 100. Correspondingly, the multiple parts of the tab 200 separated by the partition groove 210 can also extend along the direction from the tab 200 to the current collector 100, thereby ensuring that multiple parts of the tab 200 can be stably connected to the current collector 100.

[0045] In some implementations, reference Figure 1 and Figure 3 As shown, the electrode tab 200 of this application may include multiple sub-electrode tabs 220, which are separated by a partition groove 210, such that adjacent sub-electrode tabs 220 are located on both sides of the partition groove 210. The bottom wall of the partition groove 210 has a gap with the current collector 100, so that adjacent sub-electrode tabs 220 are connected, thus the electrode tab 200 as a whole can be a single structure.

[0046] Specifically, the bottom wall of the partition groove 210 is opposite to the slot 211 on the side of the electrode tab 200. By creating a gap between the bottom wall of the partition groove 210 and the current collector 100, the partition groove 210 will not extend into the current collector 100. Thus, the sub-electrode portions 220 formed by the partition groove 210 of the electrode tab 200 are interconnected on the side closest to the current collector 100. The sub-electrode portions 220 on both sides of the partition groove 210 can be electrically connected, making the electrode tab 200 a single, integral structure. When the electrode tab 200 is electrically connected to an external structure and energized, both sub-electrode portions 220 can be energized simultaneously, further improving the overall integrity of the electrode tab 200.

[0047] In some implementations, reference Figure 1 and Figure 3 As shown, the width of the partition groove 210 of the tab 200 in this application can be set to gradually change. Specifically, along the direction from the groove opening 211 of the partition groove 210 to the bottom wall of the partition groove 210, the width of the partition groove 210 gradually decreases. In this way, the width of the partition groove 210 near the groove opening 211 is relatively larger, and the width of the partition groove 210 near the bottom wall is relatively smaller.

[0048] By making the width of the portion of the separator 210 near the opening 211 relatively large, the opening of the opening 211 is made relatively large, thus increasing the separation degree of the two sub-electrode tabs 220 on the side away from the current collector 100. When the tabs 200 pass through the conveyor roller 300, the internal stress generated in the two sub-electrode tabs 220 is reduced, thereby further reducing the risk of tearing when the tabs 200 pass through the conveyor roller 300 and improving the yield of the electrode sheets of this application.

[0049] By making the width of the part of the partition groove 210 near the bottom wall relatively smaller, the tab 200 can make the connection between the adjacent sub-tabs 220 located on both sides of the partition groove 210 more stable, thereby making the structure of the tab 200 more stable.

[0050] In some implementations, reference Figure 1 and Figure 3 As shown, the sidewalls of the partition groove 210 in this application can be configured as inclined surfaces. Specifically, the two opposite sidewalls of the partition groove 210 are inclined surfaces, so that the partition groove 210 as a whole can have a "V" shape structure, thereby allowing the width of the partition groove 210 to gradually change. In addition, by making the partition groove 210 as a whole have a "V" shape structure, the transition of the width change of the partition groove 210 can be made smoother, ensuring the overall structural stability of the tab 200.

[0051] The sidewalls of the partition groove 210 in this application can also be configured as curved surfaces. Specifically, the two opposite sidewalls of the partition groove 210 are curved surfaces, allowing the partition groove 210 to have an overall "U" shape, thus enabling the width of the partition groove 210 to gradually change. By making the partition groove 210 have an overall "U" shape, the transition of the width change of the partition groove 210 can be made smoother, ensuring the overall structural stability of the tab 200. In addition, the curved sidewalls of the partition groove 210 can further reduce the internal stress of the tab 200 when it bends as it passes through the conveyor roller 300, effectively preventing the tab 200 from tearing when it bends as it passes through the conveyor roller 300.

[0052] In addition, in other embodiments, the inner wall of the partition groove 210 may be provided with multiple stepped structures, which can also make the width of the partition groove 210 gradually decrease from the groove opening 211 to the bottom wall.

[0053] In some implementations, reference Figure 1 and Figure 3 As shown, when the number of the dividing groove 210 in this application is one, the dividing groove 210 can be disposed in the middle part of the electrode tab 200, so that the dividing groove 210 can divide the electrode tab 200 into two parts by the middle part of the electrode tab 200. In this way, the two sub-electrode tabs 220 can be symmetrically arranged along the center of the dividing groove 210, so that the structures of the two sub-electrode tabs 220 are consistent, thereby ensuring that the performance of the two sub-electrode tabs 220 is consistent when electrically connected to the user's external structure.

[0054] When there are multiple partition grooves 210, the multiple partition grooves 210 can be evenly spaced along a direction perpendicular to the direction from the current collector 100 to the electrode 200. This allows two adjacent sub-electrode 220 located on both sides of the partition groove 210 to be symmetrically arranged along the center of the corresponding partition groove 210, thereby making the structure of the multiple sub-electrode 220 consistent and ensuring that the performance of the multiple sub-electrode 220 is consistent when electrically connected to the user's external structure.

[0055] When there are multiple partition slots 210, and the number of partition slots 210 is odd, one of the partition slots 210 can be set in the middle part of the tab 200.

[0056] In some implementations, reference Figure 1 and Figure 3 As shown, the direction of the tab 200 to the current collector 100 in this application intersects with the length direction of the current collector 100, so that the tab 200 can be located on one side of the width direction of the current collector 100. Specifically, the tab 200 in this application can be applied to cylindrical batteries or square batteries.

[0057] In other embodiments, the direction of the tab 200 to the current collector 100 can be set to be consistent with the length direction of the current collector 100, so that the tab 200 can be located on one side of the length direction of the current collector 100. Specifically, the tab 200 of this application can be applied to blade batteries or other types of batteries.

[0058] In some implementations, reference Figure 3 and Figure 4 As shown, the number of tabs 200 in this application can be set to two, and the two tabs 200 can be a positive tab 200 and a negative tab 200, respectively. When the electrode sheet of this application is applied to a cylindrical battery or a square battery, both the positive tab 200 and the negative tab 200 are connected to the end of the current collector 100, and the positive tab 200 and the negative tab 200 are located on the same side of the current collector 100. There is a gap between the positive tab 200 and the negative tab 200 to prevent the positive tab 200 and the negative tab 200 from contacting each other and short-circuiting.

[0059] In some implementations, reference Figure 1 and Figure 3 As shown, the width of the tab 200 gradually decreases from the end furthest from the current collector 100 to the end where the tab 200 connects to the current collector 100, allowing the tab 200 to have a trapezoidal structure. This allows the weight distribution of the tab 200 to be more concentrated on the side closer to the current collector 100 while maintaining its length, resulting in a more stable connection between the tab 200 and the current collector 100.

[0060] When the electrode of this application is used in a blade battery, the positive tab 200 and the negative tab 200 are respectively connected to the opposite sides of the current collector 100.

[0061] Based on the aforementioned electrodes, this application also proposes a battery cell comprising a housing, a separator, and a plurality of the aforementioned electrodes, wherein the electrodes are stacked within the housing along their thickness direction. A separator is disposed between adjacent electrodes, and one of two adjacent electrodes is designated as the first electrode, and the other as the second electrode. The first and second electrodes have opposite polarities.

[0062] In addition, refer to Figure 4 As shown, the tabs 200 of adjacent electrodes can also be connected by ultrasonic welding.

[0063] It should be noted that the terms "one embodiment," "embodiment," "exemplary embodiment," "some embodiments," etc., mentioned in the specification indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0064] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part by context, the term "one or more" as used in the text can be used to describe any feature, structure, or characteristic of the singular meaning, or a combination of features, structures, or characteristics of the plural meaning. Similarly, at least in part by context, terms such as "a" or "the" can also be understood to convey either singular or plural usage.

[0065] It should be readily understood that the terms “on,” “above,” and “on top of” in this application should be interpreted in the broadest possible sense, such that “on” means not only “directly on something” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “on something” but also “on something” without an intermediate feature or layer therebetween (i.e., directly on something).

[0066] Furthermore, for ease of explanation, spatially relative terms such as "below," "below," "under," "above," and "above" may be used to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation other than those shown in the figures. The device may have other orientations (rotated 90° or in other orientations), and the spatially relative descriptive terms used herein may be interpreted accordingly.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An electrode sheet, characterized in that, include: current collector(100); The electrode (200) is connected at one end to the current collector (100). The electrode tab (200) has a partition groove (210) that extends through the electrode tab (200) along its thickness direction. One end of the partition groove (210) extends to the side of the electrode tab (200), and the other end of the partition groove (210) extends toward the current collector (100). The partition groove (210) divides the electrode tab (200) into at least two parts.

2. The electrode sheet according to claim 1, characterized in that, One end of the dividing groove (210) extends to the side of the tab (200) away from the current collector (100).

3. The electrode sheet according to claim 2, characterized in that, The electrode tab (200) includes a plurality of sub-electrode tabs (220), and the partition groove (210) is located between adjacent sub-electrode tabs (220). The bottom wall of the partition groove (210) is spaced from the current collector (100) so that adjacent sub-electrode tabs (220) are connected.

4. The electrode sheet according to claim 2, characterized in that, The partition groove (210) has a slot (211) located on the side of the tab (200), and the width of the partition groove (210) gradually decreases along the direction from the slot (211) to the bottom wall of the partition groove (210).

5. The electrode sheet according to claim 4, characterized in that, The sidewall of the partition groove (210) is an inclined surface or an arc surface.

6. The electrode sheet according to claim 2, characterized in that, The dividing groove (210) is located in the middle of the tab (200).

7. The electrode sheet according to any one of claims 1-6, characterized in that, The number of the partition grooves (210) is multiple, and the multiple partition grooves (210) are evenly spaced along the length direction of the current collector (100).

8. The electrode sheet according to any one of claims 1-6, characterized in that, The direction from the tab (200) to the current collector (100) is perpendicular to the length direction of the current collector (100).

9. The electrode sheet according to claim 8, characterized in that, The number of the tabs (200) is two, and the two tabs (200) are arranged at intervals along the length direction of the current collector (100) on the same side of the current collector (100).

10. A battery cell, characterized in that, Includes the electrode as described in any one of claims 1-9.

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