Pole piece, battery cell and pole piece manufacturing equipment

Abstract

The utility model discloses a pole piece, battery cell and pole piece manufacturing equipment, the pole piece comprises a middle area and two edge areas, along the width direction of the pole piece, the two edge areas are respectively connected with the two ends of the middle area, the middle area is provided with a plurality of first grooves, and the first grooves are respectively connected with the two ends of the middle area. The edge area is provided with a plurality of first grooves, the edge area is provided with a plurality of second grooves, the orientation of an opening of each first groove is the same as that of an opening of each second groove, and the volume of each first groove is larger than that of each second groove. The pole piece disclosed by the utility model can effectively avoid the situation that powder falls off from the edge.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an electrode sheet, a battery cell, and an electrode sheet manufacturing equipment. Background Technology

[0002] In related technologies, electrode embossing is a process that mechanically embosses the surfaces of positive and negative electrodes in a battery. Specifically, during the electrode conveyor belt operation, the electrode passes through an embossing roller and a back roller, causing the rollers to rotate and creating a raised or recessed structure on the electrode. However, after embossing, the edges of existing electrodes are prone to excessive deformation due to the formed raised or recessed structure, leading to powder shedding and reduced electrode performance. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes an electrode sheet that can effectively prevent powder from falling off the edges.

[0004] This utility model also proposes a battery cell.

[0005] This utility model also proposes an electrode manufacturing equipment.

[0006] An electrode sheet according to a first aspect of the present invention includes: a middle region and an edge region, wherein two edge regions are provided, and the two edge regions are respectively connected to the two ends of the middle region along the width direction of the electrode sheet. The middle region is provided with a plurality of first grooves, and the edge regions are provided with a plurality of second grooves. The opening orientation of the first grooves is the same as the opening orientation of the second grooves, wherein the volume of the first grooves is greater than the volume of the second grooves.

[0007] The electrode sheet according to the embodiment of the present utility model has at least the following beneficial effects: the electrode sheet includes a middle area and two edge areas along the width direction, wherein the middle area is provided with a first groove and the edge areas are provided with a second groove. The volume of the first groove is larger than the volume of the second groove. Since the volume of the second groove is smaller, the deformation of the electrode edge is smaller. Therefore, the active material at the edge area is not easy to fall off, so the electrode sheet can effectively avoid the situation of powder falling off the edge.

[0008] According to some embodiments of the present invention, the volume of the second groove gradually decreases along the direction from the middle region to the edge region.

[0009] According to some embodiments of the present invention, the depth of the second groove gradually decreases along the direction from the middle region to the edge region.

[0010] According to some embodiments of the present invention, the diameter of the second groove gradually decreases along the direction from the middle region to the edge region.

[0011] According to some embodiments of the present invention, the depth of the first groove is A, where 80μm≤A≤120μm.

[0012] According to some embodiments of the present invention, the depth of the second groove is B, where 20μm≤B≤80μm.

[0013] According to some embodiments of the present invention, the electrode sheet has a width of L1, and the size of the intermediate region along the width direction of the electrode sheet is L2, where 0.5 ≤ L2 / L1 ≤ 0.8.

[0014] According to some embodiments of the present invention, the electrode sheet includes at least one rolled area and at least one unrolled area. Along the length direction of the electrode sheet, the unrolled area and the rolled area are alternately arranged. The rolled area includes the middle area and the edge area. The unrolled area is not provided with the first groove and the second groove.

[0015] The battery cell according to a second aspect embodiment of the present invention includes the electrode sheet as described in any one of the first aspect embodiments.

[0016] The battery cell according to the embodiments of this utility model has at least the following beneficial effects: the electrode sheet includes a central region and two edge regions along its width direction, wherein a first groove is provided in the central region and a second groove is provided in the edge regions. The volume of the first groove is larger than the volume of the second groove. Since the volume of the second groove is smaller, the active material at the edge regions is less likely to fall off, thereby effectively preventing powder from falling off the electrode sheet. Specifically, the electrode sheet can effectively prevent powder from falling off the edges. Furthermore, the battery cell having this electrode sheet has better performance.

[0017] An electrode manufacturing apparatus according to a third aspect of the present invention includes an embossing roller, the electrode manufacturing apparatus manufacturing an electrode as described in any one of the first aspect embodiments via the embossing roller.

[0018] The electrode manufacturing equipment according to the embodiments of this utility model has at least the following beneficial effects: the embossing roller can manufacture electrode sheets, which include a central region and two edge regions along their width. The central region is provided with a first groove, and the edge regions are provided with second grooves. The volume of the first groove is larger than the volume of the second groove. Because the volume of the second groove is smaller, the active material at the edge regions is less likely to fall off. That is, after embossing the electrode sheet with the embossing roller of this application, powder shedding at the edges of the electrode sheet can be effectively avoided, thereby improving the yield of the electrode sheet.

[0019] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0021] Figure 1 This is a schematic diagram of the electrode sheets in some embodiments of the present invention;

[0022] Figure 2 These are cross-sectional views of the electrode sheets in some embodiments of this utility model;

[0023] Figure 3 This is a schematic diagram of the embossing roller in the electrode manufacturing equipment of some embodiments of this utility model.

[0024] Figure label:

[0025] Electrode 100, middle area 200, first groove 210, edge area 300, second groove 310, rolling area 400, unrolled area 500, embossing roller 600, body part 610, first protrusion 620, second protrusion 630. Detailed Implementation

[0026] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0027] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0029] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0030] In the description of this utility model, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0031] In related technologies, electrode embossing is a process that mechanically embosses the surfaces of positive and negative electrodes in a battery. Specifically, during the electrode conveyor belt operation, the electrode passes through an embossing roller and a back roller, causing the rollers to rotate and forming a raised / lower structure on the electrode. However, after embossing, the edges of existing electrodes are prone to excessive deformation due to the formed raised / lower structure, leading to powder shedding and reduced electrode performance. Therefore, this application proposes an electrode design.

[0032] Please refer to Figures 1 to 2In some embodiments, the electrode 100 includes a central region 200 and two edge regions 300, with the two edge regions 300 respectively connected to both ends of the central region 200 along the width direction of the electrode 100. Specifically, the shape of the electrode 100 can be elongated or rectangular. The electrode 100 can be a positive electrode 100 or a negative electrode 100. The electrode 100 includes a foil and an active material layer, with the active material layer coated on both sides of the foil in the thickness direction. That is, both the edge regions 300 and the central region 200 have foil and an active material layer. The central region 200 is provided with a plurality of first grooves 210, and the edge regions 300 are provided with a plurality of second grooves 310. That is, the electrode 100 has first grooves 210 and second grooves 310, which can be formed on the electrode 100 by an embossing process. The opening orientation of the first groove 210 is the same as the opening orientation of the second groove 310. That is, one side surface of the electrode 100 is recessed to form a first groove 210 and a second groove 310, while the other side surface of the electrode 100 has a protrusion. The shapes of the first groove 210 and the second groove 310 are not specifically limited; for example, the shapes of the first groove 210 and the second groove 310 can be hemispherical, square, etc. The volume of the first groove 210 is greater than the volume of the second groove 310. Specifically, the electrode 100 includes a central region 200 and two edge regions 300 along its width. The central region 200 is provided with the first groove 210, and the edge regions 300 are provided with the second groove 310. The volume of the first groove 210 is greater than the volume of the second groove 310. Because the volume of the second groove 310 is smaller, the active material at the edge regions 300 is less likely to fall off, thus effectively preventing powder from falling off the edges of the electrode 100. In existing technology, the grooves in the middle region 200 and the edge region 300 of the electrode 100 have the same volume. Therefore, the active material layer in the edge region 300 is prone to detachment due to large deformation, which leads to poor performance of the electrode 100. Specifically, the electrode 100 can effectively prevent powder from falling off at the edge.

[0033] Furthermore, it should be added that the first groove 210 has a large volume. When the electrode 100 forms a battery cell, the first groove 210 can have sufficient gaps for electrolyte storage, thereby improving the wettability of the battery cell. The design of the second groove 310 not only effectively avoids powder shedding, but also effectively reduces the risk of edge breakage of the electrode 100 and effectively improves the problem of uneven tension of the electrode 100.

[0034] Furthermore, please refer to... Figures 1 to 2The middle area 200 is provided with multiple first grooves 210, which can be arranged in an array. The edge area 300 is provided with multiple second grooves 310, which can also be arranged in an array. The volume of the second groove 310 is smaller than the volume of the first groove 210. Specifically, the volume of each second groove 310 is smaller than the volume of each first groove 210.

[0035] Further, please refer to Figures 1 to 2 In some embodiments, the volume of the second groove 310 gradually decreases along the direction from the middle region 200 to the edge region 300. That is, the volume of the plurality of second grooves 310 can decrease in a stepwise manner from the middle region 200 to the edge region 300. For example, the volume of the second groove 310 near the middle region 200 is the largest, and the volume of the second groove 310 far from the middle region 200 is the smallest. This design can further prevent powder shedding at the edge of the electrode 100.

[0036] Further, please refer to Figures 1 to 2 The volume of the second groove 310 gradually decreases along the direction from the middle region 200 to the edge region 300, specifically by gradually decreasing the depth of the second groove 310. That is, in some embodiments, the depth of the second groove 310 gradually decreases along the direction from the middle region 200 to the edge region 300. Specifically, the bottom area of ​​the plurality of second grooves 310 remains unchanged, while the depth of the second grooves 310 changes, thereby changing the volume of the second grooves 310.

[0037] Furthermore, the specific way in which the volume of the second groove 310 gradually decreases along the direction from the middle region 200 to the edge region 300 can be that the diameter of the second groove 310 gradually decreases, that is, please refer to... Figures 1 to 2 In some embodiments, the diameter of the second groove 310 gradually decreases along the direction from the middle region 200 to the edge region 300. Specifically, as the diameter of the second groove 310 decreases, the bottom area of ​​the second groove 310 decreases, while the depth of the second groove 310 remains unchanged, thereby changing the volume of the second groove 310.

[0038] Furthermore, in some embodiments, the depth of the first groove 210 is A, where 80μm ≤ A ≤ 120μm. Specifically, the depth of the first groove 210 can be 80μm, 90μm, 100μm, 110μm, 115μm, or 120μm. When the depth of the first groove 210 is less than 80μm, the volume of the first groove 210 may be small, resulting in less electrolyte that the electrode 100 can store after forming the battery cell. When the depth of the first groove 210 is greater than 120μm, the deformation of the electrode 100 may be large, potentially causing the active material layer to detach from the foil, resulting in poor performance of the electrode 100.

[0039] Furthermore, in some embodiments, the depth of the second groove 310 is B, where 20μm ≤ B ≤ 80μm. Specifically, when there is only one second groove 310, its depth can be the depth of the first groove 210 minus 60μm. When there are multiple second grooves 310, the minimum depth of the second groove 310 is 20μm. To elaborate further, the minimum depth of the second groove 310 is not less than 20μm. If the minimum depth of the second groove 310 is too small, then the second groove 310 can store less electrolyte, and the effect on improving battery performance is not significant.

[0040] Furthermore, in some embodiments, the width of the electrode 100 is L1, and the size of the intermediate region 200 along the width direction of the electrode 100 is L2, where 0.5 ≤ L2 / L1 ≤ 0.8. Specifically, the size of the intermediate region 200 can be one-half or four-fifths of the width of the electrode 100. When the ratio of L2 / L1 is less than 0.5, the space occupied by the intermediate region 200 is too small, and the space occupied by the edge region 300 is too large. Since the volume of the second groove 310 is smaller than the volume of the first groove 210, this results in a smaller amount of electrolyte that the electrode 100 can store. When the ratio of L2 / L1 is greater than 0.8, the size of the intermediate region 200 is larger, and the size of the edge region 300 is smaller, which increases the difficulty of setting the second groove 310 in the edge region 300.

[0041] Further, please refer to Figures 1 to 2In some embodiments, the electrode 100 includes at least one rolled area 400 and at least one unrolled area 500. Along the length of the electrode 100, the two ends of the unrolled area 500 are respectively connected to two rolled areas 400. The rolled area 400 includes a middle area 200 and an edge area 300. The unrolled area 500 does not have a first groove 210 and a second groove 310. That is, the electrode 100 can be elongated, divided into multiple rolled areas 400 and multiple unrolled areas 500 along its length. When the electrode 100 is being conveyed, it can be rolled by an embossing roller 600 to form the rolled areas 400 and the unrolled areas 500. The unrolled area 500 can have reserved positions for electrode tab welding or adhesive application, effectively preventing incomplete welding of the electrode tab and electrode 100 or the adhesive tape being rolled off.

[0042] In some embodiments, the battery cell includes an electrode 100 as described in any of the above embodiments. The electrode 100 includes a central region 200 and two edge regions 300 along its width. The central region 200 is provided with a first groove 210, and the edge regions 300 are provided with second grooves 310. The volume of the first groove 210 is larger than the volume of the second groove 310. Because the volume of the second groove 310 is smaller, the active material at the edge regions 300 is less likely to fall off, thus the electrode 100 can effectively prevent powder shedding at the edges. Specifically, the electrode 100 can effectively prevent powder shedding at the edges. Furthermore, the battery cell having this electrode 100 has better performance.

[0043] In some embodiments, please refer to Figure 3 The electrode manufacturing equipment includes an embossing roller 600. The electrode manufacturing equipment uses the embossing roller 600 to manufacture the electrode 100 according to any of the above embodiments. Specifically, the embossing roller 600 can manufacture the electrode 100, which includes a central region 200 and two edge regions 300 along its width. The central region 200 is provided with a first groove 210, and the edge regions 300 are provided with second grooves 310. The volume of the first groove 210 is larger than the volume of the second groove 310. Because the volume of the second groove 310 is smaller, the active material at the edge regions 300 is less likely to fall off. That is, after embossing the electrode 100 with the embossing roller 600 of this application, the powder shedding at the edges of the electrode 100 can be effectively avoided, thereby improving the yield of the electrode 100.

[0044] The following describes the specific structure of the embossing roller 600. Please refer to [link / reference]. Figure 3The embossing roller 600 includes a body portion 610, a first protrusion 620, and a second protrusion 630. The body portion 610 may be cylindrical. Both the first protrusion 620 and the second protrusion 630 are connected to the body portion 610 and protrude relative to the body portion 610. The volume of the first protrusion 620 is larger than the volume of the second protrusion 630, so that when the embossing roller 600 rolls the electrode sheet 100, it can form a first groove 210 and a second groove 310 on the electrode sheet 100. The number of the first protrusion 620 and the second protrusion 630 is not specifically limited. The first protrusion 620 may be located in the middle of the body portion 610, and the second protrusions 630 may be located at both ends of the first protrusion 620. From the first protrusion 620 to the second protrusion 630, the volume of the plurality of second protrusions 630 may gradually decrease.

[0045] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. An electrode, characterized in that, include: The electrode has a middle region and an edge region. There are two edge regions, which are connected to the two ends of the middle region along the width direction of the electrode. The middle region has a plurality of first grooves, and the edge regions have a plurality of second grooves. The openings of the first grooves face the same direction as the openings of the second grooves. The volume of the first groove is greater than the volume of the second groove.

2. The electrode sheet according to claim 1, characterized in that, Along the direction from the middle region to the edge region, the volume of the second groove gradually decreases.

3. The electrode sheet according to claim 2, characterized in that, The depth of the second groove gradually decreases along the direction from the middle region to the edge region.

4. The electrode sheet according to claim 2, characterized in that, The diameter of the second groove gradually decreases along the direction from the middle region to the edge region.

5. The electrode sheet according to claim 1, characterized in that, The depth of the first groove is A, where 80μm≤A≤120μm.

6. The electrode sheet according to claim 1, characterized in that, The depth of the second groove is B, where 20μm≤B≤80μm.

7. The electrode sheet according to claim 1, characterized in that, The width of the electrode is L1, and the size of the intermediate region along the width direction of the electrode is L2, where 0.5 ≤ L2 / L1 ≤ 0.

8.

8. The electrode sheet according to claim 1, characterized in that, The electrode sheet includes at least one rolled area and at least one unrolled area. Along the length of the electrode sheet, the unrolled area and the rolled area are alternately arranged. The rolled area includes the middle area and the edge area. The unrolled area is not provided with the first groove and the second groove.

9. A battery cell, characterized in that, Includes the electrode as described in any one of claims 1 to 8.

10. Electrode manufacturing equipment, characterized in that, The electrode manufacturing equipment includes an embossing roller, and the electrode manufacturing equipment manufactures the electrode according to any one of claims 1 to 8 by means of the embossing roller.

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