Battery cell, battery device, and electric device

Abstract

The application discloses a battery monomer, a battery device and a power utilization device, and belongs to the technical field of batteries. The battery monomer comprises an electrode assembly, the electrode assembly comprises a first pole piece, the first pole piece comprises a first current collector, a first active material layer and an insulating layer, the first current collector comprises a first body and a first lug, the first lug extends from a first edge of the first body, and the first active material layer is arranged on the surface of the first body; the first lug comprises a first part covered by the insulating layer and a second part not covered by the insulating layer, and the first part is connected to the second part and the first body; wherein the first lug is provided with reinforcing ribs, part of the reinforcing ribs are located on the second part, and the other part of the reinforcing ribs are located on the first part. The technical scheme provided by the application can improve the reliability of the battery monomer.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a battery cell, a battery device, and an electrical device. Background Technology

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. Among these, batteries, as a core component of new energy vehicles, have high requirements regarding reliability.

[0003] In battery technology, the electrodes of a battery cell need to be wound and unwound multiple times during the manufacturing process. This can easily cause creases at the weaker tabs, leading to stress concentration and potentially resulting in creases or even cracks in the tabs, which is detrimental to improving the reliability of the battery cell. Utility Model Content

[0004] This application provides a battery cell, a battery device, and an electrical device, which can effectively improve the reliability of the battery cell.

[0005] In a first aspect, embodiments of this application provide a battery cell including an electrode assembly. The electrode assembly includes a first electrode sheet, which includes a first current collector, a first active material layer, and an insulating layer. The first current collector includes a first body and a first tab. The first tab extends from a first edge of the first body, and the first active material layer is disposed on the surface of the first body. The first tab includes a first portion covered by the insulating layer and a second portion not covered by the insulating layer. The first portion connects the second portion and the first body. The first tab is provided with reinforcing ribs, with a portion of the reinforcing ribs located in the second portion and another portion located in the first portion.

[0006] In the above technical solution, a reinforcing rib is provided on the first tab, so that the reinforcing rib can form a high-strength area on the first tab. This allows the stress generated by the deformation to be more evenly distributed in the area with the reinforcing rib when the weaker first tab is overturned due to external force during transportation and use, thus reducing the risk of stress concentration on the first tab. At the same time, since some reinforcing ribs are located in the second part and others are located in the first part, the first part with the insulating layer and the second part without the insulating layer and the first active material layer share the stress generated by the deformation, thereby further reducing the risk of stress concentration causing creases or even cracks in the first tab, thus improving the reliability of the battery cell.

[0007] In some embodiments, the reinforcing rib includes at least one first reinforcing rib, and the same first reinforcing rib includes a first segment and a second segment arranged continuously, the second segment being located in the second portion and the first segment being located in the first portion.

[0008] In the above technical solution, the same first reinforcing rib includes a second segment and a first segment that are continuously arranged. The second segment is located in the second part, and the first segment is located in the first part. When the area of ​​the second segment in the second part is deformed by external force, the stress generated by the deformation can be distributed along the second segment of the first reinforcing rib to the first segment. This allows the first part of the first electrode tab, which has higher strength due to the presence of an insulating layer, to bear part of the stress through the first segment. This reduces the risk of stress concentration at the connection between the first and second parts due to the difference in strength between the first and second parts. Consequently, it reduces the risk of creases or even cracks appearing on the first electrode tab due to stress concentration at the connection between the first and second parts, thereby improving the reliability of the battery cell.

[0009] In some embodiments, the length direction of the first reinforcing rib intersects with the first edge.

[0010] In the above technical solution, since the length direction of the first reinforcing rib intersects with the first edge, that is, the length direction of the first reinforcing rib forms an angle with the first edge, when the stress generated by the deformation of the first electrode tab is distributed along the length direction of the first reinforcing rib, the first reinforcing rib can decompose the shear stress generated by the deformation of the first electrode tab relative to the first body into stress components along the direction of the first reinforcing rib. In this way, the axial tensile strength of the first electrode tab is used to bear the shear stress, reducing the risk of stress concentration caused by shearing, thereby reducing the risk of creases or even cracks in the first electrode tab, and thus improving the reliability of the battery cell.

[0011] In some embodiments, the length direction of the first reinforcing rib is perpendicular to the first edge.

[0012] In the above technical solution, the length direction of the first reinforcing rib is perpendicular to the first edge. When the stress generated by the deformation of the first electrode is distributed along the length direction of the first reinforcing rib, the first reinforcing rib can decompose the shear stress generated by the flipping of the first electrode relative to the first body into stress components along the direction of the first reinforcing rib. This further utilizes the higher axial tensile strength of the first electrode to bear the shear stress, further reduces the risk of stress concentration caused by shear, and further reduces the risk of creases or even cracks in the first electrode, thereby further improving the reliability of the battery cell.

[0013] In some embodiments, the number of the first reinforcing ribs is multiple, and the multiple first reinforcing ribs are spaced apart along a first direction, which is parallel to the first edge.

[0014] In the above technical solution, multiple first reinforcing ribs are spaced apart along a first direction, which is parallel to the first edge. On the one hand, this increases the area of ​​the high-strength region on the first electrode tab; on the other hand, when creases or even cracks appear on the first electrode tab, the first reinforcing ribs adjacent to the creases or cracks in the first direction can limit the creases or cracks from continuing to extend along the first direction, thereby reducing the risk of defects on the first electrode tab continuing to expand and improving the reliability of the battery cell.

[0015] In some embodiments, along the second direction, the size of the first portion is H1, the size of the first segment is H2, and the condition 0.1 ≤ H2 / H1 ≤ 0.9 is satisfied. The thickness directions of the second direction, the first edge, and the first tab are perpendicular to each other.

[0016] In the above technical solution, when H2 / H1≥0.1, the first segment has sufficient dimensions in the second direction, allowing the first part to withstand more stress, thereby reducing the risk of stress concentration at the connection between the first and second parts due to the difference in strength. When H2 / H1≤0.9, there is a certain distance between the end of the first segment away from the second segment and the edge connecting the first part and the first body, thereby reducing the risk of the first reinforcing rib affecting the setting of the first active material layer on the first body, allowing the first active material layer to be better set on the first body, thus improving the reliability of the battery cell during use. Therefore, when 0.1≤H2 / H1≤0.9, it can both reduce the risk of stress concentration at the connection between the first and second parts due to the difference in strength and improve the reliability of the battery cell during use.

[0017] In some embodiments, 1 / 3 ≤ H2 / H1 ≤ 2 / 3.

[0018] In the above technical solution, when H2 / H1≥1 / 3, the first segment has sufficient dimensions in the second direction, allowing the first part to withstand more stress, thereby further reducing the risk of stress concentration at the connection between the first and second parts due to the difference in strength. When H2 / H1≤2 / 3, there is a certain distance between the end of the first segment away from the second segment and the edge connecting the first part and the first body, further reducing the risk of the first reinforcing rib affecting the setting of the first active material layer on the first body, allowing the first active material layer to be better set on the first body, thereby improving the reliability of the battery cell during use. Therefore, when 1 / 3≤H2 / H1≤2 / 3, it can further reduce the risk of stress concentration at the connection between the first and second parts due to the difference in strength, and further improve the reliability of the battery cell during use.

[0019] In some embodiments, the reinforcing rib includes at least one second reinforcing rib and at least one third reinforcing rib, wherein the second reinforcing rib is located in the second portion and the third reinforcing rib is located in the first portion.

[0020] In the above technical solution, the second reinforcing rib is located in the second part to strengthen the second part, thereby facilitating the release of internal stress in the second part and improving the strength of the second part. The third reinforcing rib is located in the first part to strengthen the first part, so that the first part with the insulating layer and the second part without the insulating layer and the first active material layer can jointly bear the stress generated by deformation, thereby reducing the risk of stress concentration causing creases or even cracks in the first tab, thereby improving the reliability of the battery cell.

[0021] In some embodiments, the area of ​​the reinforcing rib is S1, and the area of ​​the first electrode lug is S2, satisfying 0.1≤S1 / S2<1.

[0022] In the above technical solution, when S1 / S2≥0.1, the reinforcing rib can strengthen the first tab in a sufficient area, thereby reducing the risk of stress concentration in the first tab and improving the reliability of the battery cell.

[0023] In some embodiments, 0.3 ≤ S1 / S2 ≤ 0.7.

[0024] In the above technical solution, when S1 / S2≥0.3, the reinforcing rib can further strengthen the first tab in a sufficient area, thereby reducing the risk of stress concentration in the first tab and improving the reliability of the battery cell; when S1 / S2≤0.7, there is a certain processing allowance area on the first tab, thereby reducing the processing difficulty of the reinforcing rib and reducing the production cost of the battery cell; therefore, when 0.3≤S1 / S2≤0.7, the reliability of the battery cell can be further improved and the production cost of the battery cell can be reduced.

[0025] In some embodiments, the first body includes a first coating area and a first transition area, the first transition area being disposed between the first tab and the first coating area; the first active material layer is disposed on the surface of the first coating area, and neither the first transition area nor the first tab is provided with the first active material layer; a portion of the insulating layer is disposed on the surface of the first transition area, and another portion is disposed on the surface of the first portion.

[0026] In the above technical solution, a portion of the insulating layer is disposed on the surface of the first transition region, so that the insulating layer fills the gap between the first transition region and the second active material layer of the second electrode, thereby reducing impurities falling into the gap, thereby reducing the risk of the second active material layer of the second electrode in the first transition region being electrically connected through metal impurities, leading to a short circuit inside the battery cell, and improving the reliability of the battery cell.

[0027] In some embodiments, the insulating layer comprises an inorganic filler and a binder, wherein the weight ratio of the inorganic filler to the binder is 4.1-9.6.

[0028] In the above technical solution, when the weight ratio of mechanical filler to binder is greater than 4.1, the insulating layer contains sufficient inorganic filler, thereby giving the insulating layer better insulation performance, reducing the risk of internal short circuits in the battery cell, and improving the reliability of the battery cell; when the weight ratio of mechanical filler to binder is less than 9.6, the insulating layer contains sufficient binder, thereby giving the insulating layer better adhesion, reducing the risk of insulating layer detachment, and improving the reliability of the battery cell; therefore, when 0.1≤H2 / H1≤0.9, both the risk of internal short circuits in the battery cell and the risk of insulating layer detachment can be reduced.

[0029] In some embodiments, the inorganic filler includes one of boehmite, Al2O3, SiO2, and TiO2.

[0030] In the above technical solutions, boehmite, Al2O3, SiO2 and TiO2 have good insulation and moderate strength. Using the above materials as inorganic fillers in the insulation layer can not only improve the insulation of the insulation layer, but also reduce the risk of scratching and puncturing the separator, thereby improving the reliability of the battery cell.

[0031] In some embodiments, the adhesive includes polyvinylidene fluoride.

[0032] In the above technical solution, polyvinylidene fluoride has good adhesion and is easy to obtain. Using polyvinylidene fluoride as a binder in the insulating layer can improve the adhesion and reduce the manufacturing cost of the insulating layer, thereby reducing the production cost of the battery cell.

[0033] In some embodiments, the first electrode is a positive electrode.

[0034] In some embodiments, along a first direction, the maximum size of the first tab is W1, and the size of the electrode assembly is W2, satisfying 1 / 9 ≤ W1 / W2 ≤ 1 / 6, and the first direction is parallel to the first edge.

[0035] In the above technical solution, when W1 / W2≥1 / 9, the first tab can have a certain maximum size, thus, with a certain thickness, the first tab has a certain flow area, which helps to reduce the internal resistance of the battery cell, thereby reducing the internal heat generation of the battery cell and improving the reliability of the battery cell. When W1 / W2≤1 / 6, the second tab of the second electrode can be given a certain installation space, which facilitates the processing of the battery cell. Therefore, when 1 / 9≤W1 / W2≤1 / 6, it can both reduce the internal heat generation of the battery cell, thereby improving the reliability of the battery cell, and facilitate the processing of the battery cell.

[0036] In some embodiments, 1 / 8 ≤ W1 / W2 ≤ 1 / 7.

[0037] In the above technical solution, when W1 / W2≥1 / 8, the first tab can have a certain maximum size, thus allowing the first tab to have a larger current-passing area while maintaining a certain thickness. This further reduces the internal resistance of the battery cell, thereby further reducing the internal heat generation of the battery cell and further improving the reliability of the battery cell. When W1 / W2≤1 / 7, the second tab of the second electrode can be given a larger installation space, thus further facilitating the processing of the battery cell. Therefore, when 1 / 8≤W1 / W2≤1 / 7, it can further reduce the internal heat generation of the battery cell, thereby further improving the reliability of the battery cell, and further facilitating the processing of the battery cell.

[0038] In some embodiments, the electrode assembly further includes a second electrode and a separator. The second electrode has the opposite polarity to the first electrode; the separator is disposed between the first electrode and the second electrode.

[0039] In the above technical solution, by placing a separator between the first electrode and the second electrode, the risk of internal short circuits in the battery cell caused by the overlap of the first electrode and the second electrode is reduced, thereby improving the reliability of the battery cell.

[0040] In some embodiments, the electrode assembly has a wound structure.

[0041] In the above technical solution, since the electrode assembly is a wound structure, during the electrode assembly forming process, compared with the case of the electrode assembly being a stacked structure, the first electrode sheet needs to be wound and unwound more times, which makes the first electrode tab more prone to creases or even cracks. Therefore, some reinforcing ribs are located in the main body and other reinforcing ribs are located in the root, so that the root coated with the insulating layer and the main body without the insulating layer and the first active material layer share the stress generated by deformation, thereby further reducing the risk of stress concentration causing creases or even cracks in the first electrode tab, thereby improving the reliability of the battery cell.

[0042] Secondly, embodiments of this application also provide a battery device, including a battery cell as described in any embodiment of the first aspect.

[0043] Thirdly, embodiments of this application also provide an electrical device, which includes a battery cell as described in any embodiment of the first aspect, the battery cell being used to provide electrical energy; or, the electrical device includes a battery device as described in the second aspect, the battery device being used to provide electrical energy. Attached Figure Description

[0044] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0046] Figure 2 Exploded views of the structure of the battery device provided in some embodiments of this application;

[0047] Figure 3 This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0048] Figure 4 This is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0049] Figure 5 This is a schematic diagram of the structure of the first electrode provided in some embodiments of this application;

[0050] Figure 6 for Figure 5 Enlarged view of point A in the middle;

[0051] Figure 7 for Figure 5 BB section view;

[0052] Figure 8 This application provides a schematic diagram of the structure of a first type of first electrode tab in some embodiments;

[0053] Figure 9 This is a schematic diagram of the structure of a second type of first electrode provided in some embodiments of this application;

[0054] Figure 10 A schematic diagram of the structure of a third type of first electrode provided in some embodiments of this application;

[0055] Figure 11 A schematic diagram of the structure of a fourth type of first electrode provided in some embodiments of this application;

[0056] Figure 12 This is a schematic diagram of the structure of a fifth type of first electrode provided in some embodiments of this application.

[0057] Icons: 1000 - Vehicle; 100 - Battery assembly; 10 - Housing; 11 - First housing body; 12 - Second housing body; 20 - Battery cell; 21 - Casing; 21A - Housing; 21B - End cap; 22 - Electrode assembly; 221 - First electrode; 2211 - First current collector; 22111 - First body; 22111A - First coating area; 22111B - First transition area; 22111C - First edge; 22112 - First tab; 22112A - ... Part 1; 22112B - Second Part; 221121 - Reinforcing Rib; 221121A - First Reinforcing Rib; 221121B - Second Section; 221121C - First Section; 221121E - Fourth Reinforcing Rib; 2212 - First Active Material Layer; 2213 - Insulating Layer; 222 - Second Electrode; 223 - Separating Membrane; 22A - Electrode Tab; 23 - Adapter; 24 - Electrode Terminal; 200 - Controller; 300 - Motor; X - First Direction; Y - Second Direction. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0059] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0060] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0061] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0062] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0063] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0064] In this application, "multiple" means two or more (including two).

[0065] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0066] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0067] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0068] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0069] In some embodiments, the positive electrode can be a positive electrode sheet, which may include a positive current collector and a positive active material disposed on at least one surface of the positive current collector.

[0070] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0071] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative current collector.

[0072] As an example, the negative electrode sheet may include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0073] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0074] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0075] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical and mechanical stability.

[0076] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0077] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0078] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0079] In some embodiments, the electrode assembly is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0080] In some implementations, the electrode assembly is a stacked structure.

[0081] As an example, multiple positive and negative electrode plates can be set, and multiple positive and multiple negative electrode plates can be stacked alternately.

[0082] As an example, multiple positive electrode sheets can be set, and negative electrode sheets are folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0083] As an example, both the positive and negative electrode sheets are folded to form multiple stacked folded segments.

[0084] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0085] As an example, the separator can be continuously arranged between any adjacent positive or negative electrode plates by folding or rolling.

[0086] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0087] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0088] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0089] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0090] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity.

[0091] In related technologies, a battery cell generally includes a casing and an electrode assembly. The casing may include a housing and an end cap. The housing has an opening. After the electrode assembly is installed inside the housing, the opening of the housing can be closed by the end cap to form a sealed space inside the housing to accommodate the electrode assembly.

[0092] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.

[0093] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0094] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0095] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing by fixing the battery module in the housing.

[0096] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0097] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0098] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0099] The following discussion will primarily focus on rectangular battery cells. It should be understood that the embodiments described below are also applicable in some respects to cylindrical battery cells, pouch cell cells, or blade cell cells.

[0100] The development of battery technology must take into account multiple design factors, such as energy density, cycle life, discharge capacity, charge / discharge rate and other performance parameters. In addition, the reliability of the battery device also needs to be considered.

[0101] The development of battery technology must take into account multiple design factors, such as energy density, cycle life, discharge capacity, charge / discharge rate and other performance parameters. In addition, battery safety also needs to be considered.

[0102] During the use of a battery cell, if the battery pack is shaken, the electrode assembly inside the cell will also shake, causing the tabs of the electrode assembly to bend and deform under external force. This generates significant internal stress, and because the tabs themselves have relatively low strength, they are prone to creases or even cracks, reducing the reliability of the battery cell.

[0103] Based on the above considerations, in order to effectively reduce the risk of creases or even cracks appearing on the tabs during subsequent die-cutting or winding processes and improve the reliability of the battery cell, this application provides a battery cell including an electrode assembly. The electrode assembly includes a first electrode sheet, which includes a first current collector, a first active material layer, and an insulating layer. The first current collector includes a first body and a first tab. The first tab extends from a first edge of the first body, and the first active material layer is disposed on the surface of the first body. The first tab includes a first portion covered by the insulating layer and a second portion not covered by the insulating layer. The first portion connects the second portion and the first body. Reinforcing ribs are provided on the first tab, with some reinforcing ribs located in the second portion and others located in the first portion.

[0104] In this type of battery cell, a reinforcing rib is provided on the first tab, so that the reinforcing rib can form a high-strength area on the first tab. This allows the stress generated by the deformation to be more evenly distributed in the area with the reinforcing rib when the weaker first tab is overturned due to external force during transportation and use, thus reducing the risk of stress concentration on the first tab. At the same time, since some reinforcing ribs are located in the second part and some reinforcing ribs are located in the first part, the first part with the insulating layer and the second part without the insulating layer and the first active material layer share the stress generated by deformation, thereby further reducing the risk of stress concentration causing creases or even cracks in the first tab, thus improving the reliability of the battery cell.

[0105] For ease of explanation, the following embodiments will be described using a vehicle as an example of an electrical device according to an embodiment of this application.

[0106] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle 1000. The battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to supply power to the vehicle 1000; for example, the battery device 100 can serve as the operating power source or general power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 controls the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0107] In some embodiments of this application, the battery device 100 can not only serve as the operating power or power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0108] Please refer to Figure 2 and Figure 3 , Figure 2 This is an exploded view of the structure of the battery device 100 provided in some embodiments of this application. Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of this application. The battery device 100 includes a housing 10 and battery cells 20, which are housed within the housing 10.

[0109] The housing 10 provides assembly space for the battery cell 20, and the housing 10 can adopt various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which cover each other, and together define an assembly space for accommodating the battery cell 20. The second housing body 12 may be a hollow structure open at one end, and the first housing body 11 may be a plate-like structure, with the first housing body 11 covering the open side of the second housing body 12 so that the first housing body 11 and the second housing body 12 together define the assembly space; alternatively, the first housing body 11 and the second housing body 12 may both be hollow structures open on one side, with the open side of the first housing body 11 covering the open side of the second housing body 12.

[0110] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder, a cuboid, or a cube. For example, in... Figure 2 In the middle, the shape of box 10 is a cuboid.

[0111] In the battery device 100, there can be one or more battery cells 20 disposed within the housing 10. When there are multiple battery cells 20 disposed within the housing 10, they can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel configurations. Multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery device 100 can also consist of multiple battery cells 20 first connected in series, in parallel, or in a mixed configuration to form a battery module, and then multiple battery modules are connected in series, in parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10.

[0112] In some embodiments, the battery device 100 may also include other structures. For example, the battery device 100 may also include a busbar for connecting multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20.

[0113] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 20 can be in the form of a cuboid, cylinder, prism, or other shapes. For example, in... Figure 3 In the middle, the battery cell 20 has a cuboid structure.

[0114] Please refer to Figure 3 The battery cell 20 refers to the smallest unit that makes up the battery assembly 100. Please refer to... Figure 3The battery cell 20 includes a housing 21, an electrode assembly 22, and other functional components. The electrode assembly 22 is housed within the housing 21. The housing 21 includes an end cap 21B and a casing 21A. The end cap 21B is a component that closes onto the opening of the casing 21A to isolate the internal environment of the battery cell 20 from the external environment. Exemplarily, the shape of the end cap 21B may be adapted to the shape of the casing 21A to fit the casing 21A. Functional components such as electrode terminals 24 may be provided on the end cap 21B. The electrode assembly 22 may be provided with tabs 22A, which are portions of the electrode assembly 22 used to guide current into and out of the electrode assembly 22, respectively. The electrode terminals 24 can be electrically connected to the electrode assembly 22 via an adapter 23 for outputting or inputting electrical energy into the battery cell 20. In some embodiments, the end cap 21B may also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. In some embodiments, an insulating element may be provided on the inner side of the end cap 21B. The insulating element can be used to isolate the electrical connection components within the housing 21A from the end cap 21B to reduce the risk of short circuits. Exemplarily, the insulating element may be made of plastic, rubber, etc.

[0115] The housing 21A is an assembly used to cooperate with the end cap 21B to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 22, electrolyte and other components.

[0116] Electrode assembly 22 is the component in the battery cell 20 where electrochemical reactions occur. Electrode assembly 22 is mainly formed by stacking positive and negative electrode plates, and a separator is typically provided between the positive and negative electrode plates. The portions of the positive and negative electrode plates containing active material constitute the second part 22112B of electrode assembly 22, while the portions of the positive and negative electrode plates without active material each constitute tabs 22A. Positive and negative tabs 22A can be located together at one end of the second part 22112B or respectively at both ends of the second part 22112B. During the charging and discharging process of the battery device 100, the positive and negative active materials react with the electrolyte, and the tabs 22A are connected to the electrode terminals 24 via adapter 23 to form a current loop.

[0117] Please refer to Figure 4 and Figure 5 Please refer to Figure 6 and Figure 7 , Figure 4 This is a schematic diagram of the structure of the electrode assembly 22 provided in some embodiments of this application. Figure 5 This is a schematic diagram of the structure of a first electrode 221 provided in some embodiments of this application. Figure 6 for Figure 5 Enlarged view of point A in the middle. Figure 7 for Figure 5 Cross-sectional view of BB. This application provides a battery cell 20, including an electrode assembly 22. The electrode assembly 22 includes a first electrode 221, which includes a first current collector 2211, a first active material layer 2212, and an insulating layer 2213. The first current collector 2211 includes a first body 22111 and a first tab 22112. The first tab 22112 extends from a first edge 22111C of the first body 22111. The first active material layer 2212 is disposed on the first body 22111. Surface; the first electrode tab 22112 includes a first part 22112A covered by an insulating layer 2213 and a second part 22112B not covered by the insulating layer 2213. The first part 22112A connects the second part 22112B and the first body 22111. The first electrode tab 22112 is provided with reinforcing ribs 221121, with one part of the reinforcing ribs 221121 located in the second part 22112B and the other part of the reinforcing ribs 221121 located in the first part 22112A.

[0118] In some embodiments, the first electrode 221 is a positive electrode, and the first current collector 2211 may be a metal foil or a composite current collector. For example, aluminum with a silver-plated surface may be used as the metal foil.

[0119] In some embodiments, the first electrode 221 is a positive electrode, and the first active material layer 2212 may include lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium manganese iron phosphate, and lithium manganese iron phosphate and carbon composites. Examples of lithium transition metal oxides may include, but are not limited to, at least one of lithium cobalt oxides (such as LiCoO2), lithium nickel oxides (such as LiNiO2), lithium manganese oxides (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides (such as LiNi1 / 3Co1 / 3Mn1 / 3O2 (also abbreviated as NCM333), LiNi0.5Co0.2Mn0.3O2 (also abbreviated as NCM523), LiNi0.5Co0.25Mn0.25O2 (also abbreviated as NCM211), LiNi0.6Co0.2Mn0.2O2 (also abbreviated as NCM622), LiNi0.8Co0.1Mn0.1O2 (also abbreviated as NCM811), lithium nickel cobalt aluminum oxides (such as LiNi0.85Co0.15Al0.05O2) and their modified compounds.

[0120] The first body 22111 is the part of the first current collector 2211 used to set the first active material layer 2212. For example, the first body 22111 has the first active material layer 2212 on one side in its thickness direction, or the first body 22111 has the first active material layer 2212 on both sides that are opposite to each other in its thickness direction.

[0121] The first tab 22112 is the part of the first current collector 2211 used to supply current to flow into or out of the first body 22111.

[0122] In some embodiments, the first electrode 221 is a positive electrode, and a plurality of first tabs 22112 are stacked to form a positive tab 22A.

[0123] The first edge 22111C is an edge of the first body 22111.

[0124] In some implementations, the electrode assembly 22 is a wound structure, and the first edge 22111C is an edge of the first body 22111 in the direction of the winding axis.

[0125] In some embodiments, the electrode assembly 22 is a stacked structure, and the first edge 22111C is an edge of the first body 22111 in a direction perpendicular to its thickness direction.

[0126] Insulating layer 2213, as the name suggests, is a coating with insulating properties.

[0127] The first part 22112A is the part where the first electrode tab 22112 is connected to the first body 22111;

[0128] The second part 22112B is the portion of the first tab 22112 that does not have the first active material layer 2212 and the insulating layer 2213. It is used for stacking to form a connection portion that electrically connects the tab 22A of the electrode assembly 22 to the adapter 23.

[0129] The reinforcing rib 221121 is a structure disposed on the surface of the first electrode tab 22112 to enhance the strength of a portion of the first electrode tab 22112. Exemplarily, the reinforcing rib 221121 can be a strip of metal foil welded to the surface of the first electrode tab 22112, or, referring to... Figure 7 The reinforcing rib 221121 can be the indentation formed by compressing the first electrode tab 22112.

[0130] The statement "One part of the reinforcing rib 221121 is located in the second part 22112B, and another part of the reinforcing rib 221121 is located in the first part 22112A" can be understood as follows: the reinforcing rib 221121 is a single piece, with part of the reinforcing rib 221121 located in the second part 22112B, and another part of the reinforcing rib 221121 located in the second part 22112B; or, the reinforcing rib 221121 is a split piece, with part of the structure of the reinforcing rib 221121 located in the second part 22112B, and another part of the structure of the reinforcing rib 221121 located in the second part 22112B.

[0131] In this embodiment, a reinforcing rib 221121 is provided on the first tab 22112 so that the reinforcing rib 221121 can form a high-strength area on the first tab 22112. This allows the stress generated by the deformation to be more evenly distributed in the area where the reinforcing rib 221121 is provided when the weaker first tab 22112 undergoes flip deformation during winding and unwinding, thereby reducing the risk of stress concentration on the first tab 22112. At the same time, since some of the reinforcing ribs 221121 are located in the second part 22112B and the other part of the reinforcing ribs 221121 are located in the first part 22112A, the first part 22112A with the insulating layer 2213 and the second part 22112B without the insulating layer 2213 and the first active material layer 2212 share the stress generated by the deformation, thereby further reducing the risk of stress concentration causing creases or even cracks in the first tab 22112, thus improving the reliability of the battery cell 20.

[0132] Please refer to Figure 6 Please refer to Figures 8-10 , Figures 8-10 The diagram illustrates the structure of three types of first tabs 22112 provided in some embodiments of this application. According to some embodiments of this application, the reinforcing rib 221121 includes at least one first reinforcing rib 221121A. The same first reinforcing rib 221121A includes a second segment 221121B and a first segment 221121C that are continuously arranged. The second segment 221121B is located in the second part 22112B, and the first segment 221121C is located in the first part 22112A.

[0133] The first reinforcing rib 221121A is a reinforcing rib 221121 with its two ends located at the second part 22112B and the first part 22112A, respectively. The second segment 221121B is the portion of the first reinforcing rib 221121A located in the second part 22112B, and the first segment 221121C is the portion of the first reinforcing rib 221121A located in the first part 22112A. Exemplarily, the first reinforcing rib 221121A may extend in a straight line, or it may extend in a curve.

[0134] In some embodiments, please refer to Figure 8 and Figure 9 The end of the second segment 221121B that is away from the first segment 221121C can be located between the edge of the second part 22112B that is away from the first part 22112A and the first part 22112A.

[0135] In some embodiments, please refer to Figure 10 and Figure 11The end of the second segment 221121B away from the first segment 221121C can extend to the edge of the second part 22112B away from the first part 22112A.

[0136] In some embodiments, please refer to Figure 9 The end of the second segment 221121B away from the first segment 221121C can be located between the edge of the second part 22112B away from the first part 22112A and the first part 22112A. The reinforcing rib 221121 also includes a fourth reinforcing rib 221121E, which is located on the side of the second segment 221121B away from the first segment 221121C. On a plane perpendicular to the second direction Y, the orthographic projection of the first reinforcing rib 221121A and the orthographic projection of the fourth reinforcing rib 221121E do not overlap at least partially.

[0137] In this embodiment, the same first reinforcing rib 221121A includes a continuously arranged first segment 221121C and a second segment 221121B. The second segment 221121B is located in the second part 22112B, and the first segment 221121C is located in the first part 22112A. Therefore, when the area of ​​the second part 22112B containing the second segment 221121B deforms, the stress generated by the deformation can be distributed along the second segment 221121B of the first reinforcing rib 221121A to the first segment 221121C, thereby causing the stress in the first tab 22112 to... The first part 22112A, which has a higher strength due to the insulating layer 2213, bears part of the stress through the first segment 221121C. This reduces the risk of stress concentration at the connection between the first part 22112A and the second part 22112B due to the difference in strength between them. Consequently, it reduces the risk of creases or even cracks appearing on the first tab 22112 due to stress concentration at the connection between the first part 22112A and the second part 22112B, thereby improving the reliability of the battery cell 20.

[0138] Please refer to Figure 6 Please refer to Figures 8-10 According to some embodiments of this application, the length direction of the first reinforcing rib 221121A intersects with the first edge 22111C.

[0139] "The length direction of the first reinforcing rib 221121A intersects with the first edge 22111C" means that the length direction of the first reinforcing rib 221121A forms an angle with the length direction of the first edge 22111C.

[0140] In some embodiments, please refer to Figure 10 The length direction of the first reinforcing rib 221121A forms an acute angle with the first edge 22111C.

[0141] In this embodiment, since the length direction of the first reinforcing rib 221121A intersects with the first edge 22111C, that is, the length direction of the first reinforcing rib 221121A forms an angle with the first edge 22111C, when the stress generated by the deformation of the first tab 22112 is distributed along the length direction of the first reinforcing rib 221121A, the first reinforcing rib 221121A can decompose the shear stress generated by the flipping of the first tab 22112 relative to the first body 22111 into stress components along the direction of the first reinforcing rib 221121A. Thus, the axial tensile strength of the first tab 22112 can be used to bear the shear stress, reducing the risk of stress concentration caused by shearing, thereby reducing the risk of creases or even cracks appearing in the first tab 22112, and thus improving the reliability of the battery cell 20.

[0142] Please refer to Figure 6 Please refer to Figure 8 and Figure 9 According to some embodiments of this application, the length direction of the first reinforcing rib 221121A is perpendicular to the first edge 22111C.

[0143] In this embodiment, the length direction of the first reinforcing rib 221121A is perpendicular to the first edge 22111C. When the stress generated by the deformation of the first tab 22112 is distributed along the length direction of the first reinforcing rib 221121A, the first reinforcing rib 221121A can decompose the shear stress generated by the flipping of the first tab 22112 relative to the first body 22111 into stress components along the direction of the first reinforcing rib 221121A. This further utilizes the higher axial tensile strength of the first tab 22112 to bear the shear stress, further reduces the risk of stress concentration caused by shearing, and further reduces the risk of creases or even cracks appearing in the first tab 22112, thereby further improving the reliability of the battery cell 20.

[0144] Please refer to Figure 6 Please refer to Figures 8-10 According to some embodiments of this application, there are multiple first reinforcing ribs 221121A, and the multiple first reinforcing ribs 221121A are spaced apart along the first direction X, and the first direction X is parallel to the first edge 22111C.

[0145] The first direction X is parallel to the first edge 22111C. In some embodiments, the electrode assembly 22 is a wound structure, and the first direction X is the length direction of the unfolded first electrode 221.

[0146] Multiple first reinforcing ribs 221121A are spaced apart along the first direction X, meaning that at least a portion of the first reinforcing rib 221121A has a gap with an adjacent first reinforcing rib 221121A in the first direction X. This is to reduce the possibility of the first electrode tab 22112 tearing due to the tensile stress between two adjacent first reinforcing ribs 221121A exceeding the ultimate stress value that the material of the first electrode tab 22112 can bear.

[0147] In some embodiments, please refer to Figure 6 Please refer to Figure 8 and Figure 9 The length directions of the multiple first reinforcing ribs 221121A are parallel to each other.

[0148] In some embodiments, please refer to Figure 9 The reinforcing rib 221121 also includes a plurality of fourth reinforcing ribs 221121E, which are located on the side of the second segment 221121B away from the first segment 221121C. In the first direction X, the plurality of fourth reinforcing ribs 221121E are spaced apart, and the plurality of first reinforcing ribs 221121A and the plurality of fourth reinforcing ribs 221121E are alternately arranged.

[0149] In some embodiments, please refer to Figure 10 The length directions of multiple first reinforcing ribs 221121A intersect, pointing from the first segment 221121C to the second segment 221121B, and the distance between two adjacent first reinforcing ribs 221121A in the first direction X gradually increases or decreases.

[0150] In this embodiment, multiple first reinforcing ribs 221121A are spaced apart along the first direction X, which is parallel to the first edge 22111C. On the one hand, this increases the area of ​​the high-strength region on the first tab 22112; on the other hand, when creases or even cracks appear on the first tab 22112, the first reinforcing ribs 221121A adjacent to the creases or cracks in the first direction X can limit the creases or cracks from continuing to extend along the first direction X, thereby reducing the risk of defects on the first tab 22112 continuing to expand and improving the reliability of the battery cell 20.

[0151] Please refer to Figure 6 According to some embodiments of this application, along the second direction Y, the size of the first part 22112A is H1, and the size of the first segment 221121C is H2, satisfying 0.1≤H2 / H1≤0.9, and the thickness directions of the second direction Y, the first edge 22111C and the first tab 22112 are perpendicular to each other.

[0152] The second direction Y is a direction that is perpendicular to the thickness directions of the first edge 22111C and the first electrode tab 22112. In some embodiments, the electrode assembly 22 is a wound structure, and the first direction X is the width direction of the unfolded first electrode 221.

[0153] The two points W1 that are furthest apart in the second direction Y of the first part 22112A are H1 apart in the second direction Y. The method for measuring the size of the first part 22112A in the second direction Y is to use a micrometer to measure the distance between the edge of the insulating material layer on the first tab 22112 that is far away from the first edge 22111C and the first edge 22111C.

[0154] The distance between the two points furthest apart in the second direction Y of the first segment 221121C is H2. The dimension of the first segment 221121C in the second direction Y is measured by using a micrometer to measure the distance in the second direction Y between the end of the first segment 221121C away from the second segment 221121B and the edge of the insulating material layer away from the first edge 22111C.

[0155] H2 / H1 can take any point value from 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or any range between the two.

[0156] In this embodiment, when H2 / H1≥0.1, the first segment 221121C has sufficient dimensions in the second direction Y, allowing the first part 22112A to withstand more stress through the first segment 221121C. This reduces the risk of stress concentration at the connection between the first part 22112A and the second part 22112B due to the difference in strength between them. When H2 / H1≤0.9, the end of the first segment 221121C furthest from the second segment 221121B connects to the edge where the first part 22112A and the first body 22111 are connected. The presence of a certain distance between them reduces the risk that the first reinforcing rib 221121A will affect the setting of the first active material layer 2212 on the first body 22111, allowing the first active material layer 2212 to be better set on the first body 22111, thereby improving the reliability of the battery cell 20 during use. Therefore, when 0.1≤H2 / H1≤0.9, it can reduce the risk of stress concentration at the connection between the first part 22112A and the second part 22112B due to the difference in strength, and also improve the reliability of the battery cell 20 during use.

[0157] Please refer to Figure 6According to some embodiments of this application, 1 / 3 ≤ H2 / H1 ≤ 2 / 3.

[0158] H2 / H1 can take any point value from 1 / 3, 3 / 8, 2 / 5, 5 / 12, 3 / 7, 4 / 9, 1 / 2, 5 / 9, 4 / 7, 7 / 12, 3 / 5, 5 / 8, 2 / 3, or any range between the two.

[0159] In this embodiment, when H2 / H1 ≥ 1 / 3, the first segment 221121C has sufficient dimensions in the second direction Y, allowing the first part 22112A to withstand more stress through the first segment 221121C. This further reduces the risk of stress concentration at the connection between the first part 22112A and the second part 22112B due to the difference in strength. When H2 / H1 ≤ 2 / 3, there is a certain distance between the end of the first segment 221121C away from the second segment 221121B and the edge connecting the first part 22112A and the first body 22111. The fixed distance further reduces the risk that the first reinforcing rib 221121A will affect the setting of the first active material layer 2212 on the first body 22111, so that the first active material layer 2212 can be better set on the first body 22111, thereby improving the reliability of the battery cell 20 during use; therefore, when 1 / 3≤H2 / H1≤2 / 3, it can further reduce the risk that stress concentration will easily occur at the connection between the first part 22112A and the second part 22112B due to the difference in strength, and further improve the reliability of the battery cell 20 during use.

[0160] Please refer to Figure 11 and Figure 12 , Figure 11 The diagram shows two structural schematics of the first tab 22112 provided in some embodiments of this application. According to some embodiments of this application, the reinforcing rib 221121 includes at least one second reinforcing rib 221121 and at least one third reinforcing rib 221121, the second reinforcing rib 221121 being located in the second portion 22112B and the third reinforcing rib 221121 being located in the first portion 22112A.

[0161] The second reinforcing rib 221121 is a reinforcing rib 221121 that is completely located in the second part 22112B, and the third reinforcing rib 221121 is a reinforcing rib 221121 that is completely located in the first part 22112A.

[0162] The second reinforcing rib 221121 can be of any shape; for example, refer to... Figure 11 and Figure 12The second reinforcing rib 221121 can be circular, and / or the second reinforcing rib 221121 can be polygonal.

[0163] The third reinforcing rib 221121 can be of any shape; for example, refer to... Figure 11 and Figure 12 The third reinforcing rib 221121 can be circular, and / or the third reinforcing rib 221121 can be polygonal.

[0164] In some implementations, refer to Figure 11 and Figure 12 The second reinforcing rib 221121 can be multiple rows arranged at intervals along the first direction X, and each row of the second reinforcing rib 221121 can be multiple sets arranged at intervals along the second direction Y, and / or the third reinforcing rib 221121 can be multiple rows arranged at intervals along the first direction X, and each row of the third reinforcing rib 221121 can be multiple sets arranged at intervals along the second direction Y.

[0165] In this embodiment, the second reinforcing rib 221121 is located in the second part 22112B to strengthen the second part 22112B, thereby facilitating the release of internal stress and improving the strength of the second part 22112B. The third reinforcing rib 221121 is located in the first part 22112A to strengthen the first part 22112A. This allows the first part 22112A with the insulating layer 2213 and the second part 22112B without the insulating layer 2213 and the first active material layer 2212 to jointly bear the stress generated by deformation, thereby reducing the risk of stress concentration causing creases or even cracks in the first tab 22112, and thus improving the reliability of the battery cell 20.

[0166] According to some embodiments of this application, the area of ​​the reinforcing rib 221121 is S1, and the area of ​​the first electrode tab 22112 is S2, satisfying 0.1≤S1 / S2<1.

[0167] The area of ​​the reinforcing rib 221121 refers to the area of ​​the orthographic projection of the reinforcing rib 221121 onto a plane perpendicular to the thickness direction of the first tab 22112. For example, when there are multiple reinforcing ribs 221121, the sum of the areas of the multiple reinforcing ribs 221121 is S1. The area of ​​the reinforcing rib 221121 is measured by using a micrometer to measure the length of each reinforcing rib 221121 in the second direction Y, and using a micrometer to measure the width of each reinforcing rib 221121 in the first direction X, calculating the product of the length and width, and then summing the resulting products sequentially.

[0168] The area of ​​the first tab 22112 refers to the area of ​​one side of the first tab 22112 perpendicular to its thickness direction. Taking the first tab 22112 as a trapezoid as an example, the method for measuring the area of ​​the first tab 22112 is to use a micrometer to measure the lengths of the two opposite edges of the first tab 22112 in the second direction Y in the first direction X, calculate the median of the lengths of the two edges, and use a micrometer to measure the height of the first tab 22112 in the second direction Y. Multiply the height by the median to obtain the area of ​​the first tab 22112.

[0169] S1 / S2 can be any point value from 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, etc., or a range of values ​​between any two.

[0170] In this embodiment, when S1 / S2≥0.1, the reinforcing rib 221121 can strengthen the first tab 22112 in a sufficient area, thereby reducing the risk of stress concentration in the first tab 22112 and improving the reliability of the battery cell 20.

[0171] According to some embodiments of this application, 0.3 ≤ S1 / S2 ≤ 0.7.

[0172] S1 / S2 can be any point value from 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, or any range between the two.

[0173] In this embodiment, when S1 / S2≥0.3, the reinforcing rib 221121 can further strengthen the first tab 22112 in a sufficient area, thereby reducing the risk of stress concentration in the first tab 22112 and improving the reliability of the battery cell 20; when S1 / S2≤0.7, the first tab 22112 has a certain processing allowance area, thereby reducing the processing difficulty of the reinforcing rib 221121 and reducing the production cost of the battery cell 20; therefore, when 0.3≤S1 / S2≤0.7, the reliability of the battery cell 20 can be further improved, and the production cost of the battery cell 20 can be reduced.

[0174] Please refer to Figure 6 Please refer to Figures 8-12According to some embodiments of this application, the first body 22111 includes a first coating area 22111A and a first transition area 22111B, the first transition area 22111B being disposed between the first tab 22112 and the first coating area 22111A; a first active material layer 2212 being disposed on the surface of the first coating area 22111A, and neither the first transition area 22111B nor the first tab 22112 being disposed of the first active material layer 2212; a portion of the insulating layer 2213 being disposed on the surface of the first transition area 22111B, and another portion being disposed on the surface of the first portion 22112A.

[0175] During the forming process of the first electrode 221, a first active material layer 2212 and an insulating layer 2213 are first set on the surface of the first current collector 2211, and then the first tab 22112 is cut out. The insulating layer 2213 is generally set with a uniform width. If the first part 22112A is not retained on the first tab 22112, then when cutting the first tab 22112, the cutter needs to move along the edge of the insulating layer 2213, which requires high cutting precision and is difficult to achieve. In addition, after cutting, the burrs on the first edge 22111C are large and can easily puncture the separator 223.

[0176] During the cutting of the first tab 22112, the cutting tool is applied directly to the insulating layer 2213. After cutting, the insulating layer 2213 is formed with a portion remaining on the first transition region 22111B and another portion remaining on the first portion 22112A of the first tab 22112. Furthermore, when the cutting tool cuts on the insulating layer 2213, burrs on the first edge 22111C are effectively reduced, thereby lowering the risk of the insulating membrane 223 being punctured.

[0177] In some embodiments, the strength of the insulating layer 2213 is greater than the strength of the first current collector 2211. On the one hand, the high-strength insulating layer 2213 can effectively support the first portion 22112A of the first tab 22112, reducing the risk of bending of the first portion 22112A of the first tab 22112 near the first transition region 22111B. On the other hand, when deformation occurs in the area of ​​the second portion 22112B with the reinforcing rib 221121, the stress generated by the deformation can be distributed along the reinforcing rib 221121, thereby allowing the first portion 22112A of the first tab 22112, which has higher strength due to the insulating layer 2213, to withstand the stress generated by folding, reducing the risk of creases or even cracks appearing in the first tab 22112 due to stress concentration at the connection between the first portion 22112A and the second portion 22112B.

[0178] When the battery cell 20 is charging, metal ions, such as lithium ions, are deintercalated from the positive electrode and intercalated into the negative electrode. However, some abnormal situations may occur, such as insufficient lithium intercalation space in the negative electrode, excessive distance between the negative and positive electrodes, excessive resistance to lithium ion intercalation into the negative electrode, or lithium ions deintercalating too quickly from the positive electrode. The deintercalated lithium ions cannot intercalate into the negative electrode active material layer of the negative electrode in an equal amount. The lithium ions that cannot intercalate into the negative electrode can only gain electrons on the surface of the negative electrode, thus forming metallic lithium. This is the phenomenon of lithium plating.

[0179] In some embodiments, the electrode assembly 22 is a wound structure, with the first electrode 221 being the positive electrode and the second electrode 222 being the negative electrode. Lithium ions in the first active material layer 2212 pass through the separator 223 and embed into the second active material layer. To ensure that lithium ions can be embedded into the second active material layer as much as possible and reduce the risk of lithium plating, the second active material layer needs to have a large width. Specifically, along the direction from the first body 22111 to the first tab 22112, one edge of the second active material layer near the first tab 22112 extends beyond the edge of the first active material layer 2212 near the first tab 22112; along the direction from the first tab 22112 to the first body 22111, another edge of the second active material layer away from the first tab 22112 extends beyond the other edge of the first active material layer 2212 away from the first tab 22112.

[0180] Multiple first tabs 22112 are arranged in a stacked manner, and the multiple first tabs 22112 are gathered together and welded to the adapter 23. During the gathering of the first tabs 22112, the first portion 22112A of some first tabs 22112 near the first transition region 22111B is prone to bending, causing these first portions 22112A of the first tabs 22112 to insert between the first electrode plate 221 and the second electrode plate 222, resulting in a short circuit risk. The insulating layer 2213 of this application can support the first tabs 22112, reducing the risk of bending of the first portions 22112A of the first tabs 22112. In addition, since the insulating layer 2213 extends to the first portion 22112A, the edge of the insulating layer 2213 away from the first active material layer 2212 extends beyond the edge of the second active material layer near the second tab 22A. Therefore, even if the second portion 22112B of the first tab 22112 is bent, the bent position maintains a certain distance from the second active material layer, thereby reducing the risk of the first tab 22112 coming into contact with the second active material layer.

[0181] In this embodiment, a portion of the insulating layer 2213 is disposed on the surface of the first transition region 22111B, so that the insulating layer 2213 fills the gap between the first transition region 22111B and the second active material layer of the second electrode 222, thereby reducing impurities falling into the gap, thereby reducing the risk of the second active material layer of the second electrode 222 in the first transition region 22111B being electrically connected through metal impurities, resulting in a short circuit inside the battery cell 20, and improving the reliability of the battery cell 20.

[0182] According to some embodiments of this application, the insulating layer 2213 includes an inorganic filler and a binder, wherein the weight ratio of the inorganic filler to the binder is 4.1-9.6.

[0183] In this embodiment, when the weight ratio of the mechanical filler to the binder is greater than 4.1, the insulating layer 2213 contains sufficient inorganic filler, thereby giving the insulating layer 2213 better insulation performance, reducing the risk of internal short circuit in the battery cell 20, and improving the reliability of the battery cell 20. When the weight ratio of the mechanical filler to the binder is less than 9.6, the insulating layer 2213 contains sufficient binder, thereby giving the insulating layer 2213 better adhesion, reducing the risk of the insulating layer 2213 falling off, and improving the reliability of the battery cell 20. Therefore, when 0.1≤H2 / H1≤0.9, both the risk of internal short circuit in the battery cell 20 and the risk of the insulating layer 2213 falling off can be reduced.

[0184] According to some embodiments of this application, the inorganic filler includes one of boehmite, Al2O3, SiO2, and TiO2.

[0185] In this embodiment, boehmite, Al2O3, SiO2 and TiO2 have good insulation and moderate strength. Using the above materials as inorganic fillers in the insulating layer 2213 can not only improve the insulation of the insulating layer 2213, but also reduce the risk of the insulating layer 2213 scratching and puncturing the separator, thereby improving the reliability of the battery cell 20.

[0186] According to some embodiments of this application, the adhesive includes polyvinylidene fluoride.

[0187] In this embodiment, polyvinylidene fluoride has good adhesion and is easy to obtain. Using polyvinylidene fluoride as a binder in the insulating layer 2213 can improve the adhesion of the insulating layer 2213 and reduce the manufacturing cost of the insulating layer 2213, thereby reducing the production cost of the battery cell 20.

[0188] According to some embodiments of this application, the first electrode 221 is a positive electrode.

[0189] In some embodiments, the first electrode 221 is a positive electrode, and the second electrode 222 is a negative electrode. The first current collector 2211 is made of aluminum or aluminum alloy, and the second current collector is made of copper or copper alloy. Since aluminum is less ductile than copper, the first current collector 2211 is more prone to creases or even cracks than the second current collector. Therefore, a portion of the reinforcing ribs 221121 is located in the second portion 22112B, and another portion of the reinforcing ribs 221121 is located in the first portion 22112A. This allows the first portion 22112A, which has the insulating layer 2213, and the second portion 22112B, which does not have the insulating layer 2213 and the first active material layer 2212, to share the stress generated by deformation. This further reduces the risk of stress concentration causing creases or cracks in the first electrode 22112, thereby improving the reliability of the battery cell 20.

[0190] Please refer to Figure 4 and Figure 5 According to some embodiments of this application, along the first direction X, the maximum size of the first tab 22112 is W1, and the size of the electrode assembly 22 is W2, satisfying 1 / 9≤W1 / W2≤1 / 6, and the first direction X is parallel to the first edge 22111C.

[0191] Along the first direction X, the maximum size of the first tab 22112 is the maximum distance between corresponding points on two opposite edges of the first tab 22112 in the first direction X. For example, when the first tab 22112 is trapezoidal, the maximum size of the first tab 22112 is the length of the edge connecting the first portion 22112A and the first edge 22111C in the first direction X.

[0192] Along the first direction X, the size of the electrode assembly 22 refers to the size of the first electrode 221 in the first direction X after the first electrode 221, the second electrode 222 and the separator 223 together constitute the electrode assembly 22.

[0193] In some embodiments, the electrode assembly 22 is a wound structure, with the first direction X parallel to the first edge 22111C of the straight segment on which the first tab 22112 is provided.

[0194] In some embodiments, the electrode assembly 22 is a stacked structure, with the first direction X parallel to the first edge 22111C of the first electrode 221.

[0195] W1 / W2 can be any point value from 1 / 9, 1 / 8, 2 / 15, 3 / 22, 5 / 36, 1 / 7, 4 / 27, 5 / 33, 11 / 72, 7 / 45, 5 / 32, 6 / 37, 1 / 6, or a range between any two.

[0196] In this embodiment, when W1 / W2≥1 / 9, the first tab 22112 can have a certain maximum size, and thus, with a certain thickness, the first tab 22112 has a certain flow area, which helps to reduce the internal resistance of the battery cell 20, thereby reducing the internal heat generation of the battery cell 20 and improving the reliability of the battery cell 20. When W1 / W2≤1 / 6, the second tab 22A of the second electrode 222 can be given a certain installation space, which facilitates the processing of the battery cell 20. Therefore, when 1 / 9≤W1 / W2≤1 / 6, it can both reduce the internal heat generation of the battery cell 20, thereby improving the reliability of the battery cell 20, and facilitate the processing of the battery cell 20.

[0197] According to some embodiments of this application, 1 / 8 ≤ W1 / W2 ≤ 1 / 7.

[0198] W1 / W2 can be any point value from 1 / 8, 2 / 15, 3 / 22, 5 / 36, 1 / 7, or any range between the two.

[0199] In this embodiment, when W1 / W2≥1 / 8, the first tab 22112 can have a certain maximum size, thus, with a certain thickness, the first tab 22112 has a larger current-passing area, thereby further reducing the internal resistance of the battery cell 20, further reducing the internal heat generation of the battery cell 20, and further improving the reliability of the battery cell 20; when W1 / W2≤1 / 7, the second tab 22A of the second electrode 222 can be given a larger installation space, thereby further facilitating the processing of the battery cell 20; therefore, when 1 / 8≤W1 / W2≤1 / 7, it can further reduce the internal heat generation of the battery cell 20, thereby further improving the reliability of the battery cell 20, and further facilitating the processing of the battery cell 20.

[0200] Please refer to Figure 4 According to some embodiments of this application, the electrode assembly 22 further includes a second electrode 222 and a separating membrane 223. The second electrode 222 has the opposite polarity to the first electrode 221; the separating membrane 223 is disposed between the first electrode 221 and the second electrode 222.

[0201] Understandably, the first electrode 221 and the second electrode 222 are two electrodes with opposite polarities. Exemplarily, the first electrode 221 is a positive electrode, and the second electrode 222 is a negative electrode. The positive and negative electrodes have opposite polarities. The positive electrode may include a positive current collector and a positive active material layer, the positive active material layer being disposed on the surface of the positive current collector. In some embodiments, the two opposite surfaces of the positive current collector may each have a positive active material layer disposed thereon. In some embodiments, the positive active material layer may be disposed on one surface of the positive current collector. The negative electrode may include a negative current collector and a negative active material layer, the negative active material layer being disposed on the surface of the negative current collector. In some embodiments, the two opposite surfaces of the negative current collector may each have a negative active material layer disposed thereon. In some embodiments, the negative active material layer may be disposed on one surface of the negative current collector.

[0202] Understandably, any well-known porous membrane with good chemical and mechanical stability can be selected.

[0203] As an example, the material of the separator 223 may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator 223 may be a single-layer film or a multi-layer composite film. When the separator 223 is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a single component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0204] In some embodiments, the electrode assembly 22 is a wound structure, wherein the first electrode 221, the separator 223, and the second electrode 222 are stacked and wound to form the electrode assembly 22.

[0205] In some implementations, the electrode assembly 22 has a stacked structure, with the first electrode 221, the separator 223, and the second electrode 222 stacked in sequence to form the electrode assembly 22.

[0206] An isolation membrane 223 is disposed between the first electrode 221 and the second electrode 222 to insulate and isolate the first active material layer 2212 on the first electrode 221 and the second active material layer on the second electrode 222.

[0207] In some embodiments, the second electrode 222 is a negative electrode. The second electrode 222 includes a second current collector and a second active material layer. The second current collector includes a second body and a second tab 22A. The second tab 22A extends from the second edge of the first body 22111. The second active material layer is disposed on the surface of the second body. The second tab 22A can be located on the same side as the first tab 22112 or on opposite sides of the first tab 22112. The second current collector can be a metal foil or a composite current collector. For example, copper with a silver-plated surface can be used as the metal foil. The second active material layer can be a negative electrode active material known in the art for use in battery cells 20. As an example, the negative electrode active material can include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate. Silicon-based materials can be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials can be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0208] In this embodiment, by placing the separator 223 between the first electrode 221 and the second electrode 222, the risk of the first electrode 221 and the second electrode 222 overlapping and causing an internal short circuit in the battery cell 20 is reduced, thereby improving the reliability of the battery cell 20.

[0209] Please refer to Figure 4 According to some embodiments of this application, the electrode assembly 22 has a wound structure.

[0210] In this embodiment, since the electrode assembly 22 has a wound structure, during the forming process of the electrode assembly 22, compared to the case where the electrode assembly 22 has a stacked structure, the first electrode sheet 221 needs to be wound and unwound more times, which makes the first tab 22112 more prone to creases or even cracks. Therefore, some reinforcing ribs 221121 are located in the second part 22112B and other reinforcing ribs 221121 are located in the first part 22112A. This allows the first part 22112A with the insulating layer 2213 and the second part 22112B without the insulating layer 2213 and the first active material layer 2212 to share the stress generated by deformation, thereby further reducing the risk of stress concentration causing creases or even cracks in the first tab 22112, thus improving the reliability of the battery cell 20.

[0211] Among them, reference Figure 2 As shown, the battery device 100 may also include a housing 10, in which the battery cells 20 are housed.

[0212] In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, the first housing body 11 and the second housing body 12 covering each other, the first housing body 11 and the second housing body 12 together defining an assembly space for accommodating the battery cell 20.

[0213] Optionally, the second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure. The first box body 11 covers the open side of the second box body 12 so that the first box body 11 and the second box body 12 together define the assembly space; the first box body 11 and the second box body 12 can also be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0214] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder or a cuboid. For example, in... Figure 2 In the middle, box 10 has a rectangular structure.

[0215] Optionally, the battery cell 20 disposed within the housing 10 can be one or more. For example, in... Figure 2 In the battery device 100, a plurality of battery cells 20 are arranged inside the housing 10. The plurality of battery cells 20 can be connected in series, in parallel, or in a mixed manner. A mixed connection means that the plurality of battery cells 20 are connected in both series and parallel. The plurality of battery cells 20 can be directly connected in series, in parallel, or in a mixed manner, and then the whole assembly of the plurality of battery cells 20 is housed inside the housing 10.

[0216] The battery device 100 may also include other structures. For example, the battery device 100 may also include a busbar component that connects multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20.

[0217] It should be noted that in some embodiments, the battery device 100 may not have a housing 10. The battery device 100 includes multiple battery cells 20, and the battery device 100 composed of multiple battery cells 20 can be directly assembled to the electrical equipment to provide power to the electrical equipment through the multiple battery cells 20. That is, the housing 10 can be part of the electrical equipment. Taking a vehicle 1000 as an example, the housing 10 can be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 can be at least a part of the floor of the vehicle 1000, or a portion of the housing 10 can be at least a part of the crossbeams and longitudinal beams of the vehicle 1000.

[0218] According to some embodiments of this application, some embodiments of this application also provide an electrical device, which includes a battery cell 20 as described above, the battery cell 20 being used to provide electrical energy.

[0219] According to some embodiments of this application, see Figures 3 to 12 As shown, this application embodiment provides a battery cell 20, including an electrode assembly 22. The electrode assembly 22 includes a first electrode 221, a second electrode 222, and a separator 223, with the separator 223 disposed between the first electrode 221 and the second electrode 222. The first electrode 221 includes a first current collector 2211, a first active material layer 2212, and an insulating layer 2213. The first current collector 2211 includes a first body 22111 and a first tab 22112, with the first tab 22112 extending from a first edge 22111C of the first body 22111. The first active material layer 2212 is disposed on the first body 2211. The surface of the first electrode tab 22112 includes a second part 22112B and a first part 22112A. The first part 22112A connects the second part 22112B and the first body 22111. At least a portion of the insulating layer 2213 is disposed on the surface of the first part 22112A. The surface of the second part 22112B is not provided with the insulating layer 2213 and the first active material layer 2212. The first electrode tab 22112 is provided with reinforcing ribs 221121, with one portion of the reinforcing ribs 221121 located in the second part 22112B and the other portion located in the first part 22112A. The area of ​​the reinforcing ribs 221121 is S1, and the area of ​​the first electrode tab 22112 is S2, satisfying 0.3 ≤ S1 / S2 ≤ 0.7. The first body 22111 includes a first coating region 22111A and a first transition region 22111B, with the first transition region 22111B disposed between the first tab 22112 and the first coating region 22111A. A first active material layer 2212 is disposed on the surface of the first coating region 22111A, while neither the first transition region 22111B nor the first tab 22112 has a first active material layer 2212 disposed thereon. A portion of the insulating layer 2213 is disposed on the surface of the first transition region 22111B, and another portion is disposed on the surface of the first portion 22112A. The insulating layer 2213 includes an inorganic filler and a binder, with the weight ratio of the inorganic filler to the binder being 4.1-9.6. The inorganic filler includes one of boehmite, Al2O3, SiO2, and TiO2. The binder includes polyvinylidene fluoride. The first electrode 221 is a positive electrode. Along the first direction X, the maximum size of the first tab 22112 is W1, and the size of the electrode assembly 22 is W2, satisfying 1 / 8 ≤ W1 / W2 ≤ 1 / 7. The first direction X is parallel to the first edge 22111C. The electrode assembly 22 has a wound structure.

[0220] In some embodiments, the reinforcing rib 221121 includes at least one first reinforcing rib 221121A. Each first reinforcing rib 221121A includes a continuously arranged second segment 221121B and a first segment 221121C. The second segment 221121B is located in the second portion 22112B, and the first segment 221121C is located in the first portion 22112A. The length direction of the first reinforcing rib 221121A is perpendicular to the first edge 22111C. There are multiple first reinforcing ribs 221121A, spaced apart along a first direction X. The size of the first portion 22112A is H1, and the size of the first segment 221121C is H2, satisfying 1 / 3 ≤ H2 / H1 ≤ 2 / 3. The second direction Y, the first edge 22111C, and the thickness direction of the first tab 22112 are all perpendicular to each other.

[0221] In some embodiments, the reinforcing rib 221121 includes at least one second reinforcing rib 221121 and at least one third reinforcing rib 221121, with the second reinforcing rib 221121 located in the second portion 22112B and the third reinforcing rib 221121 located in the first portion 22112A.

[0222] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0223] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized by, Includes an electrode assembly, the electrode assembly comprising: The first electrode includes a first current collector, a first active material layer and an insulating layer. The first current collector includes a first body and a first tab. The first tab extends from a first edge of the first body and the first active material layer is disposed on the surface of the first body. The first electrode includes a first portion covered by the insulating layer and a second portion not covered by the insulating layer, wherein the first portion is connected to the second portion and the first body; The first electrode tab is provided with reinforcing ribs, with a portion of the reinforcing ribs located in the second part and another portion of the reinforcing ribs located in the first part.

2. The battery cell of claim 1, wherein, The reinforcing rib includes at least one first reinforcing rib, and the same first reinforcing rib includes a first segment and a second segment arranged continuously, the second segment being located in the second part, and the first segment being located in the first part.

3. The battery cell of claim 2, wherein, The length direction of the first reinforcing rib intersects with the first edge.

4. The battery cell of claim 3, wherein, The length direction of the first reinforcing rib is perpendicular to the first edge.

5. The battery cell of claim 3, wherein, The number of the first reinforcing ribs is multiple, and the multiple first reinforcing ribs are spaced apart along a first direction, which is parallel to the first edge.

6. The battery cell of claim 2, wherein, Along the second direction, the size of the first part is H1, and the size of the first segment is H2, satisfying 0.1≤H2 / H1≤0.

9. The thickness directions of the second direction, the first edge, and the first tab are perpendicular to each other.

7. The battery cell of claim 6, wherein, 1 / 3 ≤ H2 / H1 ≤ 2 / 3.

8. The battery cell of claim 1, wherein, The reinforcing rib includes at least one second reinforcing rib and at least one third reinforcing rib, with the second reinforcing rib located in the second part and the third reinforcing rib located in the first part.

9. The battery cell of claim 1, wherein, The area of ​​the reinforcing rib is S1, and the area of ​​the first electrode lug is S2, satisfying 0.1≤S1 / S2<1.

10. The battery cell of claim 9, wherein, 0.3≤S1 / S2≤0.

7.

11. The battery cell of claim 1, wherein, The first body includes a first coating area and a first transition area, the first transition area being disposed between the first electrode and the first coating area; the first active material layer is disposed on the surface of the first coating area, and neither the first transition area nor the first electrode has the first active material layer disposed thereon; A portion of the insulating layer is disposed on the surface of the first transition region, and another portion is disposed on the surface of the first portion.

12. The battery cell of claim 1, wherein, The insulating layer comprises inorganic fillers and binders, with the weight ratio of inorganic fillers to binders being 4.1-9.

6.

13. The battery cell of claim 12, wherein, Inorganic fillers include one of boehmite, Al2O3, SiO2, and TiO2.

14. The battery cell of claim 12, wherein, The adhesive includes polyvinylidene fluoride.

15. The battery cell of claim 1, wherein, The first electrode is a positive electrode.

16. The battery cell according to claim 1, characterized in that, Along the first direction, the maximum size of the first electrode tab is W1, and the size of the electrode assembly is W2, satisfying 1 / 9≤W1 / W2≤1 / 6, and the first direction is parallel to the first edge.

17. The battery cell according to claim 16, characterized in that, 1 / 8 ≤ W1 / W2 ≤ 1 / 7.

18. The battery cell according to claim 1, characterized in that, The electrode assembly also includes: The second electrode has the opposite polarity to the first electrode. A separator is disposed between the first electrode and the second electrode.

19. The battery cell according to claim 1, characterized in that, The electrode assembly has a wound structure.

20. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1-19.

21. An electrical appliance, characterized in that, The electrical device includes a battery cell as described in any one of claims 1-19, the battery cell being used to provide electrical energy; or... The electrical device includes the battery device as described in claim 20, the battery device being used to provide electrical energy.

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