Battery cell and battery

Abstract

Disclosed in the present invention is a battery cell, comprising: a first electrode sheet, which comprises a first tab, a first current collector and a first active material layer, the first active material layer being disposed on the first current collector, the first active material layer and the first current collector jointly defining a first slot, and the first tab being disposed in the first slot and connected to the first current collector; a first adhesive layer, which comprises a first protruding portion and a first body portion that are connected to each other, wherein the thickness of the first protruding portion is greater than that of the first body portion, the first protruding portion is disposed in the first slot and covers the first tab, and the first body portion is connected to the first active material layer; a separator, which is attached to the side of the first adhesive layer facing away from the first current collector; and a second electrode sheet, which comprises a second active material layer, the part of the second active material layer that is arranged facing the first adhesive layer being attached to the separator. The battery cell of the present invention can not only prevent the separator from being punctured, but can also have relatively high energy density.

Description

Cells and batteries Technical Field

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

[0002] In the related art, a slot is reserved on the electrode piece so that the tab is welded to the slot. After the tab is welded to the electrode piece, it is necessary to cover the welding position of the tab and the electrode piece with adhesive tape to prevent the welding burrs from piercing the diaphragm. This can effectively prevent the positive and negative poles of the battery cell from short-circuiting after the electrode piece forms a battery cell. In the prior art, in order to prevent the welding burrs from piercing the diaphragm, multiple layers of adhesive tape need to be set. Specifically, the battery cell will avoid this problem by setting two layers of adhesive tape. For example, the specific method is to first attach the first layer of adhesive tape to the position of the positive tab, and then attach the second layer of adhesive tape to the negative electrode sheet, which corresponds to the positive tab, so as to finally form two layers of adhesive tape to prevent welding burrs. However, this method will cause the adhesive tape to occupy too much thickness, thereby reducing the energy density of the battery cell.

[0003] Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a battery cell that can not only prevent the diaphragm from being punctured but also has a high energy density.

[0005] The present invention also provides a battery.

[0006] A battery cell according to an embodiment of the first aspect of the present invention includes:

[0007] A first electrode sheet, comprising a first electrode tab, a first current collector, and a first active material layer, wherein the first active material layer is disposed on the first current collector, the first active material layer and the first current collector jointly define a first groove, and the first electrode tab is disposed in the first groove and connected to the first current collector;

[0008] a first adhesive layer comprising a first protrusion and a first body connected to each other, wherein the first protrusion is thicker than the first body, wherein the first protrusion is disposed in the first groove and covers the first tab, and the first body is connected to the first active material layer;

[0009] a diaphragm, the diaphragm being bonded to a side of the first adhesive layer facing away from the first current collector;

[0010] The second pole piece includes a second active material layer, and the portion of the second active material layer facing the first adhesive layer is in contact with the diaphragm.

[0011] The battery cell according to an embodiment of the present invention has at least the following beneficial effects: because the thickness of the first protrusion of the first adhesive layer is greater than the thickness of the first main body, the welding burrs generated after the first tab and the first current collector are welded can be blocked by the first protrusion, thereby effectively preventing the diaphragm from being punctured. In addition, in the prior art, two layers of adhesive tape are required, resulting in a low energy density of the battery cell, while only one first adhesive layer is required in the present application. Therefore, the battery cell of the present application also has the characteristic of high energy density. Specifically, the battery cell can not only prevent the diaphragm from being punctured, but also has a high energy density.

[0012] According to some embodiments of the present invention, in a battery cell, one of the first electrode sheet and the second electrode sheet is a positive electrode sheet, and the other is a negative electrode sheet; the second electrode sheet further includes a second tab and a second current collector; the second active material layer is disposed on the second current collector; the second active material layer and the second current collector jointly define a second groove; the second tab is disposed in the second groove and connected to the second current collector;

[0013] The battery cell further includes a second adhesive layer, the second adhesive layer including a second protruding portion and a second main portion connected to each other, the second protruding portion being thicker than the second main portion; the second protruding portion is disposed in the second groove and covers the second tab, and the second main portion is connected to the second active material layer;

[0014] The diaphragm is bonded to the side of the second adhesive layer facing away from the second current collector, and the portion of the first active material layer facing the second adhesive layer is bonded to the diaphragm.

[0015] According to some embodiments of the battery cell of the present invention, the first active material layer defines a third groove, which is connected to the first groove, wherein the groove depth of the third groove is smaller than the groove depth of the first groove, and the first protrusion is arranged in the first groove and the third groove.

[0016] In the battery cell according to some embodiments of the present invention, the first adhesive layer includes two first body portions, and the two first body portions are respectively connected to two ends of the first protrusion.

[0017] According to some embodiments of the battery cell of the present invention, the first protrusion includes a first surface and a second surface arranged opposite to each other, and a third surface and a fourth surface arranged opposite to each other, the two ends of the first surface are respectively connected to the third surface and the fourth surface, the two ends of the second surface are respectively connected to the third surface and the fourth surface, the second surface, the third surface and the fourth surface are all connected to the first main body, and the first surface is aligned with one side edge of the first main body.

[0018] According to some embodiments of the present invention, in a battery cell, two first grooves are provided, and the two first grooves are respectively located on both sides of the first current collector; two first adhesive layers are provided, one first protrusion is located in one first groove, and the other first protrusion is located in the other first groove; and the first tab is located in one of the first grooves.

[0019] In the battery cell according to some embodiments of the present invention, the first active material layer is provided with a fourth groove, the fourth groove is communicated with the first groove, and the first body is provided in the fourth groove.

[0020] According to some embodiments of the battery cell of the present invention, the thickness of the first protrusion is 6 um to 50 um.

[0021] In the battery cell according to some embodiments of the present invention, the thickness of the first body portion is 1 um to 50 um.

[0022] A battery according to an embodiment of the second aspect of the present invention includes: a battery cell as described in any one of the embodiments of the first aspect.

[0023] The battery according to the embodiment of the present invention has at least the following beneficial effects: since the thickness of the first protrusion of the first adhesive layer is greater than the thickness of the first main body, the welding burrs generated after the welding of the first tab and the first current collector can be blocked by the first protrusion, thereby effectively preventing the diaphragm from being punctured. In addition, in the prior art, two layers of adhesive tape are required, which will result in a lower energy density of the battery cell, while in the present application, only one first adhesive layer is required. Therefore, the battery cell of the present application also has the characteristic of higher energy density. Specifically, the battery cell can not only prevent the diaphragm from being punctured, but also has a higher energy density. Furthermore, the battery with this battery cell is not only safer, but also has a longer battery life.

[0024] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0026] FIG1 is a schematic diagram of a battery cell according to a first embodiment of the present invention;

[0027] FIG2 is a schematic diagram of a battery cell according to a second embodiment of the present invention;

[0028] FIG3 is a schematic diagram of a first adhesive layer in a battery cell according to a first embodiment of the present invention;

[0029] FIG4 is a schematic diagram of a first adhesive layer in a battery cell according to a second embodiment of the present invention;

[0030] FIG5 is a schematic diagram of a first adhesive layer in a battery cell according to a third embodiment of the present invention;

[0031] FIG6 is a schematic diagram of a first electrode in a battery cell according to some embodiments of the present invention;

[0032] FIG7 is a schematic diagram of a battery cell according to a third embodiment of the present invention;

[0033] FIG8 is a schematic diagram of a battery cell according to a fourth embodiment of the present invention;

[0034] FIG. 9 is a schematic diagram of a battery cell according to a fourth embodiment of the present invention.

[0035] Reference numerals:

[0036] Battery cell 10, first electrode sheet 100, first electrode tab 110, first current collector 120, first active material layer 130, first groove 140, third groove 150, fourth groove 160, first adhesive layer 200, first protrusion 210, first surface 211, second surface 212, third surface 213, fourth surface 214, first body 220, second electrode sheet 300, second electrode tab 310, second current collector 320, second active material layer 330, second groove 340, second adhesive layer 400, second protrusion 410, second body 420, and diaphragm 500. DETAILED DESCRIPTION

[0037] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0038] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0039] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0040] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0041] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0042] Referring to Figures 1 and 3, in some embodiments, a battery cell 10 includes: a first electrode sheet 100, a first adhesive layer 200, a separator 500, and a second electrode sheet 300. The first electrode sheet 100 includes a first electrode tab 110, a first current collector 120, and a first active material layer 130. The first active material layer 130 is disposed on the first current collector 120. The first active material layer 130 and the first current collector 120 jointly define a first groove 140. The first electrode tab 110 is disposed in the first groove 140 and connected to the first current collector 120. The first electrode sheet 100 can be a positive electrode sheet. When the first electrode sheet 100 is a positive electrode sheet, the material of the first current collector 120 can be aluminum foil. The material of the first active material layer 130 can be one or more of lithium cobalt oxide, lithium nickel manganese cobalt oxide, lithium manganese iron phosphate, sodium iron phosphate, lithium vanadium phosphate, sodium vanadium phosphate, lithium vanadium oxyphosphate, sodium vanadium oxyphosphate, lithium vanadate, lithium manganate, lithium nickel oxide, lithium nickel cobalt manganate, lithium-rich manganese-based materials, lithium nickel cobalt aluminum oxide, or lithium titanate. The first pole piece 100 can also be a negative electrode piece. When the first pole piece 100 is a negative electrode piece, the material of the first current collector 120 can be copper foil. The material of the first active material layer 130 can be one or more of carbon materials (such as graphite, soft carbon, hard carbon, etc.), silicon materials (such as silicon oxide, silicon carbon, etc.), nitrides, tin-based oxides, tin alloys, nano-negative electrode materials, and intermetallic compounds. The first adhesive layer 200 includes a first protrusion 210 and a first main body 220 that are connected to each other. The thickness of the first protrusion 210 is greater than the thickness of the first main body 220.

[0043] Among them, the first protrusion 210 is arranged in the first groove 140 and covers the first electrode tab 110, and the first body portion 220 is connected to the first active material layer 130. The diaphragm 500 is bonded to the side of the first adhesive layer 200 facing away from the first current collector 120. The second electrode 300 includes a second active material layer 330, and the portion of the second active material layer 330 facing the first adhesive layer 200 is bonded to the diaphragm 500. Please refer to Figure 1, which shows the first electrode 100, the diaphragm 500, and the second electrode 300. The diaphragm 500 is not bonded to the first adhesive layer 200 and the second electrode 300 in Figure 1 for the convenience of readers. In actual products, they are bonded. Because the thickness of the first protrusion 210 of the first adhesive layer 200 is greater than the thickness of the first body 220, the welding burrs generated by the welding of the first tab 110 and the first current collector 120 can be blocked by the first protrusion 210, thereby effectively preventing the separator 500 from being punctured. In addition, in the prior art, two layers of adhesive tape are required, which results in a lower energy density of the battery cell 10. However, in the present application, only one first adhesive layer 200 is required. Therefore, the battery cell 10 of the present application also has the characteristic of higher energy density. Specifically, the battery cell 10 can not only prevent the separator 500 from being punctured, but also has a higher energy density.

[0044] It should be noted that in the prior art, in order to meet the safety performance requirements of the battery cell 10, after attaching two layers of adhesive tape, not only does this reduce the energy density, but the greater thickness of the two layers of adhesive tape also results in poor flatness of the battery cell 10, causing deformation after multiple cycles. In the battery cell 10 of the present application, the first protrusion 210 (the thicker portion) is located in the first groove 140, and the first main body 220 (the thinner portion) is connected to the first active material layer 130, thereby effectively avoiding the problem of poor flatness of the battery cell 10. In addition, only one first adhesive layer 200 is used in the present application, thus saving material and reducing the manufacturing cost of the battery cell 10.

[0045] The above description states that the first electrode sheet 100 can be a positive electrode sheet or a negative electrode sheet. When the first electrode sheet 100 is a positive electrode sheet, the second electrode sheet 300 can be used as a negative electrode sheet, and the structure of the negative electrode sheet can be set to be consistent with the structure of the positive electrode sheet, thereby further improving the energy density. Specifically, referring to Figure 2, in some embodiments, one of the first electrode sheet 100 and the second electrode sheet 300 is a positive electrode sheet and the other is a negative electrode sheet. The battery cell 10 also includes a second adhesive layer 400. The second electrode sheet 300 includes a second electrode tab 310, a second current collector 320, and a second active material layer 330. The second active material layer 330 is disposed on the second current collector 320. The second active material layer 330 and the second current collector 320 jointly define a second groove 340. The second electrode tab 310 is disposed in the second groove 340 and is connected to the second current collector 320. The second adhesive layer 400 includes a second protrusion 410 and a second body portion 420 that are connected to each other. The thickness of the second protrusion 410 is greater than the thickness of the second body portion 420. The second protrusion 410 is disposed in the second groove 340 and covers the second tab 310. The second body 420 is connected to the second active material layer 330. The separator 500 is bonded to the side of the second adhesive layer 400 facing away from the second current collector 320. The first active material layer 130 and the second adhesive layer 400 are bonded to the separator 500 at the portion facing the second adhesive layer 400. In this way, both the positive and negative electrodes of the battery cell 10 can effectively avoid the low energy density associated with two layers of adhesive tape.

[0046] It should be noted that, in this application, the first adhesive layer 200 can be used only on the first pole piece 100. After the second pole tab 310 is welded to the second pole piece 300, the second adhesive layer 400 is bonded to the first pole piece 100 instead of the second pole piece 300. In other words, a separator 500 is provided between the second adhesive layer 400 and the second pole piece 300. Specifically, referring to Figures 2 and 9, such a design allows for more flexible specifications of the battery cell 10 during manufacturing while also achieving a higher energy density.

[0047] 1 , in some embodiments, a battery cell 10 includes a first electrode sheet 100, a second electrode sheet 300, and a separator 500. Separator 500 is located between first electrode sheet 100 and second electrode sheet 300. The first electrode sheet 100, separator 500, and second electrode sheet 300 are wound together to form battery cell 10.

[0048] Further, referring to FIG. 1 , in some embodiments, along the thickness direction of the first pole piece 100, the projection of the first protrusion 210 falls within the projection range of the first groove 140. Specifically, the projection of the first protrusion 210 falling within the projection range of the first groove 140 can be specifically that the first groove 140 can be square in shape, and the first protrusion 210 can also be square in shape, wherein the area of ​​the first protrusion 210 is smaller than the area of ​​the first groove 140. In this way, the first protrusion 210 does not exceed the range of the first groove 140, thereby increasing the thickness of the battery cell 10 and resulting in a lower energy density of the battery cell 10. In addition, the projection of the first protrusion 210 can overlap with the projection of the first groove 140, so that the first protrusion 210 can cover the first groove 140 and prevent leakage of the first current collector 120.

[0049] Further, referring to FIG. 2 , in some embodiments, along the thickness direction of the second pole piece 300, the projection of the second protrusion 410 falls within the projection of the second groove 340. Specifically, the projection of the second protrusion 410 falling within the projection of the second groove 340 can be achieved by, for example, the second groove 340 can be square-shaped, and the second protrusion 410 can also be square-shaped, wherein the area of ​​the second protrusion 410 is smaller than the area of ​​the second groove 340. In this way, the second protrusion 410 does not extend beyond the second groove 340, thereby increasing the thickness of the battery cell 10 and resulting in a lower energy density of the battery cell 10. Furthermore, the projection of the second protrusion 410 can overlap with the projection of the second groove 340, so that the second protrusion 410 can cover the second groove 340 and prevent leakage of the second current collector 320.

[0050] Further, referring to Figures 5 and 6 , in some embodiments, the first adhesive layer 200 includes two first main bodies 220, each connected to the ends of the first protrusion 210. Furthermore, in some embodiments, the first active material layer 130 defines a third groove 150, which communicates with the first groove 140. The groove depth of the third groove 150 is less than that of the first groove 140. The first protrusion 210 is disposed in the first groove 140 and the third groove 150, and both first main bodies 220 are connected to the first active material layer 130. Specifically, after defining the third groove 150, the first protrusion 210 can be made larger so that it covers the first groove 140 and the third groove 150. This arrangement further ensures that after the first adhesive layer 200 covers the first electrode 100, the first current collector 120 is not exposed, thereby preventing a short circuit. Specifically, the design in which the depth of the third groove 150 is less than the depth of the first groove 140 can effectively prevent further loss of active material and leakage of the first current collector 120, compared to a design in which the depth of the third groove 150 is equal to the depth of the first groove 140. Furthermore, when the first adhesive layer 200 covers the first electrode sheet 100, if the first adhesive layer 200 becomes too thick due to processing reasons, the third groove 150 can accommodate the first adhesive layer 200, thereby effectively preventing the first adhesive layer 200 from covering the first electrode sheet 100 and increasing the thickness of the battery cell 10, thereby reducing the energy density of the battery cell 10.

[0051] It should be noted that the structures of the second adhesive layer 400 and the second pole piece 300 may also be consistent with the structures of the first adhesive layer 200 and the first pole piece 100 in the above embodiment, and will not be further described here.

[0052] Further, referring to Figures 1 and 4 , in some embodiments, the first protrusion 210 includes a first surface 211 and a second surface 212 disposed opposite each other, as well as a third surface 213 and a fourth surface 214 disposed opposite each other. The first surface 211 is connected to the third surface 213 and the fourth surface 214 at both ends, respectively. The second surface 212, the third surface 213, and the fourth surface 214 are all connected to the first body 220. The first surface 211 is aligned with a side edge of the first body 220. Specifically, the first body 220 can be shaped like a concave character, enclosing the first protrusion 210. This design prevents welding burrs from piercing the separator 500 when the first adhesive layer 200 is attached to the first electrode sheet 100, and prevents the first current collector 120 from being exposed. This improves the safety of the battery cell 10.

[0053] It should be noted that the structure of the second protrusion 410 may also be consistent with the structure of the first protrusion 210 in the above embodiment, and will not be further described here.

[0054] Furthermore, the first pole piece 100 can be manufactured by applying a slurry of the first active material layer 130 to two opposing surfaces of the first current collector 120 using an extrusion device or a gravure roller device; then cleaning the first groove 140 using a laser or scraper device. The first pole piece 100 is then produced through processes such as rolling and slitting. To facilitate laser processing, the laser device can be used to clean two opposing first grooves 140. Specifically, referring to FIG1 , in some embodiments, two first grooves 140 are provided, one located on either side of the first current collector 120, two first adhesive layers 200 are provided, one first protrusion 210 is located in one first groove 140, the other first protrusion 210 is located in the other first groove 140, and the first electrode tab 110 is located in one of the first grooves 140. The two first adhesive layers 200 cover the two first grooves 140, thereby preventing the first current collector 120 from being exposed.

[0055] It should be noted that the structure of the second pole piece 300 may also be consistent with the structure of the first pole piece 100 in the above embodiment, and will not be further described here.

[0056] Referring to Figures 7 and 8 , in some embodiments, the first active material layer 130 is provided with a fourth groove 160 , which communicates with the first groove 140 , and the first body portion 220 is disposed in the fourth groove 160 . In Figure 7 , there is no separator 500 between the first adhesive layer 200 and the first electrode piece 100 . In Figure 8 , a separator 500 is present between the first adhesive layer 200 and the first electrode piece 100 . Specifically, when the first body portion 220 is disposed in the fourth groove 160 , the thickness of the first body portion 220 is equal to the groove depth of the fourth groove 160 . For example, the groove depth of the fourth groove 160 is 1 μm to 50 μm. This ensures that after the first adhesive layer 200 is bonded to the first electrode piece 100 , the first electrode piece 100 maintains its original thickness without adding excess thickness, thereby improving the energy density of the battery cell 10 . When two first body portions 220 are provided, two fourth grooves 160 may also be provided. In addition, the groove depth of the fourth groove 160 may be smaller than the groove depth of the first groove 140 .

[0057] Furthermore, in some embodiments, the thickness of the first protrusion 210 is 6um to 50um. When the thickness of the first protrusion 210 is less than 6um, after the first protrusion 210 is set in the first groove 140, the first protrusion 210 may not be able to prevent welding burrs from penetrating, which may cause the battery cell 10 to have a short circuit risk. When the thickness of the first protrusion 210 is greater than 50um, after the first protrusion 210 is set in the first groove 140, the first protrusion 210 can prevent welding burrs from penetrating, effectively avoiding the risk of short circuit in the battery cell 10. However, if the thickness of the first protrusion 210 is too thick, it will lead to waste of processing materials and excessively high costs. At the same time, when the first protrusion 210 is too thick, the first protrusion 210 will become the thickest part of the battery cell 10, which will result in a low energy density of the battery cell 10.

[0058] It should be noted that the thickness of the second protrusion 410 can also be consistent with the thickness of the first protrusion 210 in the above-mentioned embodiment. That is, in some embodiments, the thickness of the second protrusion 410 is 6 μm to 50 μm. When the thickness of the second protrusion 410 is less than 6 μm, after the second protrusion 410 is disposed in the second groove 340, the second protrusion 410 may not prevent welding burrs from protruding, which may cause the battery cell 10 to short-circuit. When the thickness of the second protrusion 410 is greater than 50 μm, after the second protrusion 410 is disposed in the second groove 340, the second protrusion 410 can prevent welding burrs from protruding, effectively avoiding the risk of short-circuiting the battery cell 10. However, if the second protrusion 410 is too thick, it will waste processing materials and increase costs. At the same time, when the second protrusion 410 is too thick, it will become the thickest part of the battery cell 10, resulting in a lower energy density of the battery cell 10.

[0059] Furthermore, in some embodiments, the thickness of the first body portion 220 is 1 μm to 50 μm. When the thickness of the first body portion 220 is less than 1 μm, this makes processing of the first body portion 220 too difficult. When the thickness of the first body portion 220 is greater than 50 μm, this results in a larger thickness of the first body portion 220, thereby increasing the thickness of the battery cell 10 and reducing the energy density of the battery cell 10.

[0060] It should be noted that the thickness of the second body portion 420 may also be consistent with the thickness of the first body portion 220 in the above embodiment, and will not be further described here.

[0061] In some embodiments, the battery includes: a shell and the battery cell 10 of the above embodiment. The shell can be an aluminum-plastic film. The shell has a storage cavity. The battery cell 10 is arranged in the storage cavity. Since the thickness of the first protrusion 210 of the first adhesive layer 200 is greater than the thickness of the first main body 220, the welding burrs generated after the first electrode 110 and the first current collector 120 are welded can be blocked by the first protrusion 210, thereby effectively preventing the diaphragm 500 from being punctured. In addition, in the prior art, two layers of adhesive tape are required, which will result in a lower energy density of the battery cell 10, while in the present application, only one first adhesive layer 200 is required. Therefore, the battery cell 10 of the present application also has the characteristic of higher energy density. Specifically, the battery cell 10 can not only prevent the diaphragm 500 from being punctured, but also has a higher energy density. Furthermore, the battery with this battery cell 10 is not only safer, but also has a longer battery life.

[0062] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. The battery cell, characterized in that, comprises: a first electrode tab, including a first tab, a first current collector and a first active material layer, the first active material layer is disposed on the first current collector, the first active material layer and the first current collector jointly define a first groove, the first tab is disposed in the first groove and connected to the first current collector; a first adhesive layer, including a first protruding portion and a first body portion connected to each other, the thickness of the first protruding portion is greater than the thickness of the first body portion, wherein, the first protruding portion is disposed in the first groove and covers the first tab, the first body portion is connected to the first active material layer; a separator, the separator is attached to a side of the first adhesive layer facing away from the first current collector; a second electrode tab, including a second active material layer, a portion of the second active material layer facing the first adhesive layer is attached to the separator.

2. The battery cell according to claim 1, characterized in that, one of the first electrode tab and the second electrode tab is a positive electrode tab, and the other is a negative electrode tab, the second electrode tab further includes a second tab and a second current collector, the second active material layer is disposed on the second current collector, the second active material layer and the second current collector jointly define a second groove, the second tab is disposed in the second groove and connected to the second current collector; the battery cell further includes a second adhesive layer, the second adhesive layer includes a second protruding portion and a second body portion connected to each other, the thickness of the second protruding portion is greater than the thickness of the second body portion; the second protruding portion is disposed in the second groove and covers the second tab, the second body portion is connected to the second active material layer; wherein, the separator is attached to a side of the second adhesive layer facing away from the second current collector, and a portion of the first active material layer facing the second adhesive layer is attached to the separator.

3. The battery cell according to claim 1, characterized in that, the first active material layer defines a third groove, the third groove communicates with the first groove, wherein, the depth of the third groove is less than the depth of the first groove, and the first protruding portion is disposed in the first groove and the third groove.

4. The battery cell according to claim 3, characterized in that, the first adhesive layer includes two of the first body portions, and the two first body portions are respectively connected to two ends of the first protruding portion.

5. The battery cell according to claim 1, characterized in that, the first protruding portion includes a first surface and a second surface disposed opposite to each other, and a third surface and a fourth surface disposed opposite to each other, two ends of the first surface are respectively connected to the third surface and the fourth surface, two ends of the second surface are respectively connected to the third surface and the fourth surface, the second surface, the third surface and the fourth surface are all connected to the first body portion, and the first surface is aligned with a side edge of the first body portion.

6. The battery cell according to claim 1, characterized in that, There are two of the first grooves, and the two first grooves are respectively located on both sides of the first current collector. There are two of the first adhesive layers. One of the first protrusions is located in one of the first grooves, and the other first protrusion is located in the other first groove. The first tab is located in one of the first grooves.

7. The battery cell according to claim 1, characterized in that the first active material layer is provided with a fourth groove, the fourth groove communicates with the first groove, and the first body part is disposed in the fourth groove.

8. The battery cell according to claim 1, characterized in that the thickness of the first protrusion is 6 um to 50 um.

9. The battery cell according to claim 1, characterized in that the thickness of the first body part is 1 um to 50 um.

10. A battery, characterized in that it includes the battery cell according to any one of claims 1 to 9.

Images