Battery cell and battery pack
Patent Information
- Application Number
- DE212024000134
- Authority / Receiving Office
- DE · DE
- Patent Type
- Utility models
- Current Assignee / Owner
- Priority Date
- 2023-09-18
- Filing Date
- 2024-06-18
- Publication Date
- 2025-10-09
- Estimated Expiration
- 2034-06-30
AI Technical Summary
The fast charging cell structure of existing lithium-ion batteries is complex, the process is difficult, and the space is occupied, resulting in a reduction in the battery energy density.
The battery cell adopts a winding structure, through the multi-layer winding structure of the first cathode sheet and the first anode sheet, combined with the design of the connecting groove and the conducting part, the synchronous and uniform charging and discharging current is achieved, reducing the adaptation demand of the electrode.
Fast charging and discharging are achieved, reducing battery space occupation, improving battery energy density, and simplifying the battery cell manufacturing process.
Smart Images
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Abstract
Description
A battery cell and a battery Technical Field
[0001] The present invention relates to the field of new energy batteries, and in particular to a battery cell and a battery. Background Art
[0002] Soft-pack lithium-ion batteries are widely used in various digital products and mobile devices. With each successive generation of products, the demands on the battery's range and charging speed have become increasingly stringent. Typical fast-charging cells feature multiple tabs. When higher charge rates are required, this multi-tab structure is used to reduce impedance and increase charging and discharging speeds.
[0003] However, in the existing technology, whether it is a wound multi-pole structure or a stacked multi-pole structure, it is necessary to transfer a battery cell pole ear to the multi-pole ear, fold the pole ear and package it. The process is difficult and will also occupy a large battery space, resulting in a reduction in battery energy density.
[0004] Summary of the Invention
[0005] 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 achieve rapid charging and discharging and has a higher battery energy density.
[0006] The present invention also provides another battery cell.
[0007] The present invention also provides a battery having the battery cell.
[0008] A battery cell according to an embodiment of the first aspect of the present invention includes:
[0009] a first cathode sheet comprising a first current collector and a first coating layer, wherein the first current collector is provided with a first coating region, the first coating layer is applied to the first coating region, and the first cathode sheet is wound to form multiple layers;
[0010] A first anode sheet includes a second current collector and a second coating layer, the second current collector is provided with a second coating region, the second coating layer is applied to the second coating region, the second coating region includes a first region and a second region arranged side by side along a width direction, the first region corresponds to the first coating region, the size of the first region is greater than or equal to the size of the first coating region, the second region is provided with a plurality of first connecting grooves, the plurality of first connecting grooves are spaced apart along a length direction of the first anode sheet, the first anode sheet and the first cathode sheet are stacked and wound to form multiple layers, each layer is provided with at least one first connecting groove, the portion of the second current collector exposed at the first connecting groove is a first connecting region, and the first connecting regions provided in adjacent layers are abutted and connected along a thickness direction to form a first conductive portion;
[0011] a positive electrode tab, electrically connected to the first cathode sheet and extending along a width direction of the first cathode sheet;
[0012] The negative electrode tab is electrically connected to the first anode sheet and extends along the width direction of the first anode sheet.
[0013] The battery cell according to the embodiment of the present invention has at least the following beneficial effects:
[0014] When the cathode and anode sheets are wound to form a battery cell, the connection areas on each layer are connected to form a conductive section. During the battery's charge and discharge process, current flows into the battery cell through the positive and negative tabs. The connection areas on each layer of anode sheets are connected, which can ensure that the charging current of each layer is synchronized and uniform, achieving a certain degree of fast charging effect. Furthermore, compared with existing multi-tab structure batteries, there is no need for processes such as transfer welding between tabs, making it simpler to manufacture, reducing the battery space occupied by the battery cell, and improving the battery's energy density.
[0015] According to some embodiments of the present invention, along the length direction of the first anode sheet, the size of the first connecting groove is between 5 mm and 7 mm, and along the width direction of the first anode sheet, the size of the first connecting groove is between 1 mm and 3 mm.
[0016] According to some embodiments of the present invention, along the width direction of the first anode sheet, a distance between the bottom wall of the first connecting groove and the first region is greater than 1 mm.
[0017] According to some embodiments of the present invention, along the length direction of the first cathode sheet, the positive electrode tab is connected to the middle area of the first coating area in the length direction, and / or, along the length direction of the first anode sheet, the negative electrode tab is connected to the middle area of the second coating area in the length direction.
[0018] According to some embodiments of the present invention, the positive electrode tab and the negative electrode tab are arranged on the same side of the battery cell along the length direction.
[0019] A battery cell according to a second embodiment of the present invention includes:
[0020] a plurality of second cathode sheets, each of the second cathode sheets comprising a third current collector and a third coating layer, the third current collector comprising a third coating region and a protrusion, the third coating layer being coated on the third coating region;
[0021] a plurality of second anode sheets, each of the second anode sheets comprising a fourth current collector and a fourth coating layer, the fourth current collector comprising a fourth coating region, the fourth coating layer being coated on the fourth coating region; the fourth coating region comprising a third region and a fourth region arranged side by side in a width direction, the third region corresponding to the third coating region, the third region having a size greater than or equal to the third coating region, the fourth region being provided with at least one connecting groove, the portion of the fourth current collector exposed in the connecting groove being the connecting region;
[0022] a positive electrode tab, electrically connected to one of the second cathode sheets;
[0023] a negative electrode tab, electrically connected to one of the second anode sheets;
[0024] Among them, each second anode sheet and each second cathode sheet are alternately stacked to form a battery cell, each protrusion is stacked and adjacent protrusions are abutted and connected to form a connecting portion, and each second region is stacked and adjacent second regions are abutted and connected to form a second conductive portion.
[0025] The battery cell according to the embodiment of the present invention has at least the following beneficial effects: when multiple second cathode sheets and multiple second anode sheets are alternately stacked to form a battery cell, the connection areas provided on adjacent second anode sheets are connected to form a second conductive portion, and the protrusions provided on adjacent second cathode sheets are connected to form a connecting portion. During the charge and discharge process of the battery, current flows into the battery cell through the positive and negative tabs. The connection areas on each layer of second anode sheets are connected, and the protrusions on each layer of second cathode sheets are connected, which can make the charge and discharge current of the battery cell synchronous and uniform, and can achieve a fast charging effect. The battery space occupied by the battery cell can also be reduced, and the energy density of the battery can also be improved.
[0026] According to some embodiments of the present invention, along the length direction of the second anode sheet, the size of the connecting groove is between 5 mm and 7 mm, and along the width direction of the second anode sheet, the size of the connecting groove is between 1 mm and 3 mm.
[0027] According to some embodiments of the present invention, along the width direction of the second anode sheet, a distance between the bottom wall of the connecting groove and the first region is greater than 1 mm.
[0028] According to some embodiments of the present invention, the positive electrode tab and the negative electrode tab are located on the same side of the battery cell along the length direction.
[0029] The third embodiment of the present invention further provides a battery, comprising:
[0030] The housing is provided with an accommodating cavity;
[0031] The battery cell provided in the embodiment of the first aspect or the second aspect is accommodated in the accommodating cavity.
[0032] The battery according to the embodiment of the present invention has at least the following beneficial effects: since the battery adopts the battery cell provided by the embodiment of the first aspect or the second aspect, the battery has at least all the beneficial effects of the above-mentioned battery cell.
[0033] 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
[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:
[0035] FIG1 is a schematic diagram of a wound structure battery cell according to an embodiment of the present invention;
[0036] FIG2 is an exploded schematic diagram of a partial structure of a battery cell according to an embodiment of the present invention;
[0037] FIG3 is a schematic diagram of a first cathode sheet according to an embodiment of the present invention.
[0038] FIG4 is a schematic diagram of a first anode sheet according to an embodiment of the present invention;
[0039] FIG5 is a schematic diagram of a first cathode sheet according to another embodiment of the present invention;
[0040] FIG6 is a schematic diagram of a first anode sheet according to another embodiment of the present invention;
[0041] FIG7 is an exploded schematic diagram of a laminated structure battery cell according to an embodiment of the present invention;
[0042] FIG8 is a schematic diagram of a second cathode sheet according to an embodiment of the present invention;
[0043] FIG9 is a schematic diagram of a second anode plate according to an embodiment of the present invention.
[0044] Reference numerals:
[0045] A first cathode sheet 100, a first current collector 110, and a first coating area 120;
[0046] A first anode sheet 200, a second current collector 210, a first connection region 211, a second coating region 220, a first region 221, a second region 222, a first connection groove 2221, and a first conductive portion 230;
[0047] A second cathode sheet 300, a third current collector 310, a third coating region 320, and a protrusion 330;
[0048] A second anode sheet 400, a fourth current collector 410, a second connection region 411, a fourth coating region 420, a third region 421, a fourth region 422, a second connection groove 4221, and a second conductive portion 430;
[0049] The positive electrode ear is 500 and the negative electrode ear is 600. DETAILED DESCRIPTION
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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.
[0055] 1 to 6 , a first embodiment of the present invention provides a battery cell including a first anode sheet 200, a first cathode sheet 100, a positive electrode tab 500, and a negative electrode tab 600. The first cathode sheet 100 includes a first current collector 110 and a first coating layer. The first coating layer is applied to the first current collector 110 to form a first coating region 120. The first cathode sheet 100 is wound to form multiple layers. The first anode sheet 200 includes a second current collector 210 and a second coating layer. The second coating layer is applied to the second current collector 210 to form a second coating region 220. The second coating region 220 includes a first region 221 and a second region 222 arranged side by side along the width direction. The first region 221 corresponds to the first coating region 120 and is larger than or equal to the first coating region 120. The second region 222 is provided with a plurality of first connection grooves 2221 spaced apart along the length direction of the first anode sheet 200. The first anode sheet 200 and the first cathode sheet 100 are stacked and wound to form multiple layers, each layer having at least one first connection groove 2221. The portion of the second current collector 210 exposed by the first connection grooves 2221 is the first connection region 211. Along the thickness direction, the first connection regions 211 of adjacent layers abut and communicate with each other to form a first conductive portion 230. The positive electrode tab 500 is electrically connected to the first cathode sheet 100 and extends along the width direction of the first cathode sheet 100. The negative electrode tab 600 is electrically connected to the first anode sheet 200 and extends along the width direction of the first anode sheet 200. The first connection groove 2221 extends from the edge of the positive electrode sheet away from the first region 221 to the first region 221.
[0056] It should be noted that when the first cathode sheet 100 and the first anode sheet 200 are wound, the first area 221 and the second coating area 220 set in the first coating area 120 need to be set correspondingly, and a diaphragm is generally provided between the first cathode sheet 100 and the first anode sheet 200. The length of the diaphragm corresponds to the length of the first cathode sheet 100 and the first anode sheet 200, and the width of the diaphragm corresponds to the width of the first area 221 and the second coating area 220, so as to ensure that the charging and discharging functions are normally realized after the battery cell is formed.
[0057] Referring to Figure 2, after the first cathode sheet 100 and the first anode sheet 200 are wound to form a battery cell, the first connection areas 211 of each layer of the first anode sheet 200 are connected to form a first conductive portion 230. During the battery's charge and discharge process, current flows into the battery cell through the positive tab 500 and the negative tab 600. The connection of the first connection areas 211 on each layer of the first anode sheet 200 allows for synchronous and uniform charging current on each layer, achieving a certain degree of fast charging. Furthermore, compared to existing multi-tab structure batteries, there is no need for processes such as transfer welding between the tabs and multiple tabs, making manufacturing simpler, reducing the battery space occupied by the battery cell, and improving the battery's energy density. Because the second area 222 of the first anode sheet 200 protrudes beyond the first cathode sheet 100 and the separator, there is no risk of short circuiting due to contact with the cathode when the multiple first connection areas 211 are electrically connected by welding, thereby ensuring the safety of the battery cell when used in batteries. It can be understood that the first connection groove 2221 can be obtained by laser processing or digging, that is, after the second coating is completed, multiple first connection grooves 2221 are processed at corresponding positions on the first anode sheet 200, so that the first anode sheet 200, the first cathode sheet 100 and the diaphragm are wound to form multiple layers, and each layer has at least one first connection area 211. After the multiple first connection areas 211 are welded and connected to form the first conductive part 230, the charging current during the battery charging process is synchronized and uniform, achieving a certain degree of fast charging capability.
[0058] In some embodiments, after the first anode sheet 200 is wound to form multiple layers, each layer can be provided with multiple first connection areas 211, which only need to correspond one-to-one with the multiple first connection areas 211 provided in the adjacent layers, thereby ensuring that the multiple first connection areas 211 are connected in sequence to form the first conductive part 230, and multiple first conductive parts 230 are formed in the length direction of the battery cell to further increase the efficiency of charging and discharging of the battery cell.
[0059] In some embodiments, the size of the first connection groove 2221 along the length of the first anode sheet 200 is between 5 mm and 7 mm, and along the width of the first anode sheet 200, the size of the first connection groove 2221 is between 1 mm and 3 mm. Along the length of the first anode sheet 200, the size of the first connection groove 2221 can be selected to be 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, or any other value between 5 mm and 7 mm; along the width of the first anode sheet 200, the size of the first connection groove 2221 can be selected to be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, or any other value between 1 mm and 3 mm. The sizes of the first connection groove 2221 along the length and width of the electrode sheet are both within the above ranges, so that the first connection areas 211 provided in adjacent layers can have sufficient contact area when connected, thereby ensuring connection stability and current transmission efficiency. For example, when connecting by welding, the connection stability of adjacent layers can be ensured, and the first connection areas 211 of adjacent layers can be prevented from separating during use of the battery, thereby reducing fast charging performance. Specifically, the weld marks formed by welding adjacent first connection areas 211 have a length of 6 mm and a width of 1.5 mm, so that the connection between the first connection areas 211 of adjacent layers is stable.
[0060] In some embodiments, along the width direction of the first anode sheet 200, the distance between the bottom wall of the first connecting groove 2221 and the first region 221 is greater than 1 mm, and the bottom wall of the first connecting groove 2221 is parallel to the length direction of the electrode sheet. To ensure the safety of the battery cell and prevent short circuits during use, the distance between the bottom wall of the first connecting groove 2221 and the first region 221 is greater than 1 mm, thereby preventing the portion of the first current collector 110 exposed in the first connecting groove 2221 from contacting the positive electrode material. Specifically, along the width direction of the first anode sheet 200, the side of the first anode sheet 200 provided with the first connecting groove 2221 extends beyond the width of the first cathode sheet 100 by more than 4 mm, while the side of the first anode sheet 200 without the first connecting groove 2221 extends beyond the width of the first cathode sheet 100 by more than 1 mm. This ensures that the first coating area 120 provided on the first cathode sheet 100 can correspond to the second coating area 220 provided on the first anode sheet 200, thereby reducing the possibility of lithium deposition on the first cathode sheet 100.
[0061] 5 and 6 , in some embodiments, along the length direction of the first cathode sheet 100, the positive electrode tab 500 is connected to the middle region of the first coating area 120 in the length direction, and / or, along the length direction of the first anode sheet 200, the negative electrode tab 600 is connected to the middle region of the second coating area 220 in the length direction, wherein the middle region refers to a region having approximately equal dimensions from both ends of the corresponding electrode sheet in the length direction. It can be understood that both the first anode sheet 200 and the first cathode sheet 100 have a large length, and the battery cell is connected to the outside world through the positive ear 500 and the negative ear 600. The current interacts with the electrode sheet through the positive ear 500 and the negative ear 600. In the actual charging and discharging process, only the area with the active coating on the electrode sheet will participate in the reaction, so the positive ear 500 is set in the middle area of the first coating area 120, and the negative ear 600 is set in the middle area of the second coating area 220. During charging and discharging, the active materials at various positions on the first cathode sheet 100 and the first anode sheet 200 will not be too far away from the electrode ears, and the current can quickly reach various positions of the electrode sheet, thereby further improving the battery charging and discharging rate.
[0062] 3 and 4 , in other embodiments, the positive electrode tab 500 is connected to the edge of the first cathode sheet 100 , and the negative electrode tab 600 can also be connected to the edge of the first anode sheet 200 . An empty foil area is provided at the edge of the first cathode sheet 100 , and an empty foil area is also provided at the edge of the first anode sheet 200 . The positive electrode tab 500 and the negative electrode tab 600 can be directly connected to the empty foil area, thereby eliminating the need to process the active coating area of the electrode sheet, thereby simplifying the production and processing steps.
[0063] Referring to Figures 1 and 2, in some embodiments, the positive tab 500 and the negative tab 600 are disposed on the same side of the battery cell along its length. The first conductive portion 230 is formed by a plurality of stacked and interconnected first connection regions 211. The negative tab 600 is also connected to the first anode sheet 200. During charge and discharge, the negative tab 600 and the first conductive portion 230 have the same polarity, allowing the negative tab 600 to be directly connected to the first conductive portion 230. The positive tab 500 is also disposed on this side. However, during charge and discharge, the polarity of the positive tab 500 and the first conductive portion 230 are opposite. To prevent short circuits, insulation is required between the first conductive portion 230 and the positive tab 500. This insulation is typically performed using insulating adhesive to prevent short circuits in the battery cell.
[0064] It can be understood that the positive tab 500 and the negative tab 600 are arranged on the same side of the battery cell. During the battery cell forming process, the space occupied by the positive tab 500 and the negative tab 600 can be further reduced, thereby improving the energy density of the battery cell.
[0065] Referring to Figures 7 to 9 , a second embodiment of the present invention provides another battery cell, comprising a positive electrode tab 500, a negative electrode tab 600, a plurality of second cathode sheets 300, and a plurality of second anode sheets 400. Each second cathode sheet 300 includes a third current collector 310 and a third coating layer. The third current collector 310 includes a third coating region 320 and a protrusion 330. The third coating layer is applied to the third coating region 320. Each second anode sheet 400 includes a fourth current collector 410 and a fourth coating layer. The fourth coating layer is applied to the fourth current collector 410 to form a fourth coating region 420. The fourth coating region 420 includes a third region 421 and a fourth region 422 arranged side by side along the width direction. The third region 421 has a size greater than or equal to that of the third coating region 320. The fourth region 422 is provided with at least one second connecting groove 4221. The portion of the fourth current collector 410 exposed in the second connecting groove 4221 constitutes the second connecting region 411. The positive electrode tab 500 is electrically connected to one of the second cathode sheets 300. The negative tab 600 is electrically connected to one of the second anode sheets 400. The second anode sheets 400 and second cathode sheets 300 are alternately stacked to form a battery cell. The protrusions 330 are stacked, and adjacent protrusions 330 abut and connect to form a connecting portion. The fourth regions 422 are stacked, and adjacent fourth regions 422 abut and connect to form a second conductive portion 430. The connection between the multiple cathode sheets via the protrusions 330 follows the conventional connection method for multi-tab battery cells, i.e., by welding the multiple protrusions 330 together. A positive tab 500 is provided on one of the second cathode sheets 300 to allow for external current input and output.
[0066] When multiple second cathode sheets 300 and multiple second anode sheets 400 are alternately stacked to form a battery cell, the second connection areas 411 provided on adjacent second anode sheets 400 are connected to form a second conductive portion 430. During the battery's charge and discharge process, current flows into the battery cell through the positive tab 500 and the negative tab 600. The second connection areas 411 on each layer of second anode sheets 400 are connected, and each layer of second cathode sheets 300 is connected through the protrusion 330. This allows the charging and discharging currents of the battery cell to be synchronized and uniform, achieving a fast charging effect. The battery space occupied by the battery cell can also be reduced, and the battery's energy density can be improved.
[0067] In some embodiments, the size of the second connection groove 4221 along the length of the second anode sheet 400 is between 5mm and 7mm, and along the width of the second anode sheet 400, the size of the second connection groove 4221 is between 1mm and 3mm. Along the length of the second anode sheet 400, the size of the second connection groove 4221 can be selected to be 5mm, 5.5mm, 6mm, 6.5mm, 7mm, or any other value between 5mm and 7mm; along the width of the second anode sheet 400, the size of the second connection groove 4221 can be selected to be 1mm, 1.5mm, 2mm, 2.5mm, 3mm, or any other value between 1mm and 3mm. The second connection groove 4221 is within the above ranges along both the length and width of the electrode sheet, so that the second connection areas 411 provided in adjacent layers can have sufficient contact area when connected to ensure the stability of the connection and the efficiency of current transmission. For example, when connected by welding, the connection stability of adjacent layers can be ensured to prevent the second connection areas 411 of adjacent layers from separating during use of the battery, resulting in a decrease in fast charging performance. Specifically, the weld marks formed by welding adjacent second connection areas 411 have a length of 6 mm and a width of 1.5 mm, so that the connection between the second connection areas 411 of adjacent layers is stable.
[0068] In some embodiments, along the width of the second anode sheet 400, the distance between the bottom wall of the second connecting groove 4221 and the third region 421 is greater than 1 mm, and the bottom wall of the second connecting groove 4221 is parallel to the length of the second anode sheet 400. To ensure the safety of the battery cell and prevent short circuits during use, the bottom wall of the second connecting groove 4221 is spaced greater than 1 mm from the edge of the negative electrode sheet, thereby preventing contact between the third current collector 310 and the negative electrode material. Specifically, along the width of the second anode sheet 400, the side of the second anode sheet 400 provided with the second connecting groove 4221 extends beyond the width of the second cathode sheet 300 by more than 4 mm, while the side of the second anode sheet 400 without the second connecting groove 4221 extends beyond the width of the second cathode sheet 300 by more than 1 mm. This ensures that the third coating region 320 provided on the second cathode sheet 300 can correspond to the fourth coating region 420 provided on the second anode sheet 400, thereby reducing the possibility of lithium deposition on the second cathode sheet 300.
[0069] 7 , in some embodiments, the positive tab 500 and the negative tab 600 are located on the same side of the battery cell along the length direction. During the battery cell forming process, the space occupied by the positive tab 500 and the negative tab 600 can be further reduced, thereby improving the energy density of the battery cell.
[0070] A third embodiment of the present invention provides a battery (not shown) comprising a housing and a battery cell according to the first or second embodiment. The housing is provided with a housing cavity. The battery cell is housed within the housing cavity. Because the battery utilizes the battery cell according to the first or second embodiment, it possesses at least all the beneficial effects of the aforementioned battery cells, which will not be further elaborated here.
[0071] 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. A battery cell, characterized in that: include: A first cathode sheet, comprising a first current collector and a first coating, wherein the first current collector is provided with a first coating area, and the first coating is coated on the first coating area; A first anode sheet, comprising a second current collector and a second coating, wherein the second current collector is provided with a second coating area, the second coating area is coated on the second coating area, the second coating area comprises a first region and a second region arranged in parallel along a width direction, the first region corresponds to the first coating area, the size of the first region is greater than or equal to the size of the first coating area, the second region is provided with a plurality of first connecting grooves, the plurality of first connecting grooves are arranged at intervals along a length direction of the first anode sheet, the first anode sheet and the first cathode sheet are stacked and wound to form multiple layers, each layer is provided with at least one first connecting groove, the portion of the second current collector exposed in the first connecting groove is the first connecting area, and the first connecting areas arranged in adjacent layers are abutted and connected along a thickness direction to form a first conducting portion; A positive electrode tab, electrically connected to the first cathode sheet and extending along a width direction of the first cathode sheet; The negative electrode tab is electrically connected to the first anode sheet and extends along the width direction of the first anode sheet.
2. The battery cell according to claim 1, characterized in that: Along the length direction of the first anode sheet, the size of the first connecting groove is between 5 mm and 7 mm, and along the width direction of the first anode sheet, the size of the first connecting groove is between 1 mm and 3 mm.
3. The battery cell according to claim 1 or 2, characterized in that: Along the width direction of the first anode sheet, a distance between the bottom wall of the first connecting groove and the first region is greater than 1 mm.
4. The battery cell according to claim 1, characterized in that: Along the length direction of the first cathode sheet, the positive electrode tab is connected to the middle area of the first coating area in the length direction, and / or, along the length direction of the first anode sheet, the negative electrode tab is connected to the middle area of the second coating area in the length direction.
5. The battery cell according to claim 1, characterized in that: The positive electrode tab and the negative electrode tab are arranged on the same side of the battery cell along the length direction.
6. A battery cell, characterized in that: include: A plurality of second cathode sheets, wherein the second cathode sheets include a third current collector and a third coating, the third current collector includes a third coating area and a protrusion, and the third coating is coated on the third coating area; A plurality of second anode sheets, each of the second anode sheets comprises a fourth current collector and a fourth coating, the fourth current collector comprises a fourth coating area, the fourth coating is coated on the fourth coating area; the fourth coating area comprises a third region and a fourth region arranged in parallel along a width direction, the third region corresponds to the third coating area, the size of the third region is greater than or equal to the size of the third coating area, the fourth region is provided with at least one connecting groove, the fourth current collector is bare The portion exposed in the connecting groove is the connecting area; A positive electrode ear, electrically connected to one of the second cathode sheets; A negative electrode ear, electrically connected to one of the second anode sheets; Among them, each second anode sheet and each second cathode sheet are alternately stacked to form a battery cell, each protrusion is stacked and adjacent protrusions are abutted and connected to form a connecting portion, and each second region is stacked and adjacent second regions are abutted and connected to form a second conductive portion.
7. The battery cell according to claim 6, characterized in that: Along the length direction of the second anode sheet, the size of the connecting groove is between 5 mm and 7 mm, and along the width direction of the second anode sheet, the size of the connecting groove is between 1 mm and 3 mm.
8. The battery cell according to claim 6 or 7, characterized in that: Along the width direction of the second anode sheet, the distance between the bottom wall of the connecting groove and the first region is greater than 1 mm.
9. The battery cell according to claim 6, characterized in that: The positive electrode tab and the negative electrode tab are located on the same side of the battery cell along the length direction.
10. A battery, characterized in that include: The housing is provided with a receiving cavity; The battery cell according to any one of claims 1 to 9, wherein the battery cell is accommodated in the accommodation cavity.