Battery monomer, battery device and electric device

Abstract

The utility model relates to a battery monomer, a battery device and a power utilization device. The battery monomer comprises a battery cell assembly, and the battery cell assembly comprises a plurality of lamination units which are arranged in a laminated manner; the lamination unit comprises an anode pole piece, a cathode pole piece, a first separator and a second separator, the anode pole piece is provided with a first side and a second side which are oppositely arranged, and the first side of the anode pole piece is concavely provided with a first concave part; the cathode pole piece is embedded into the first concave part; the first separator covers the second side of the anode pole piece; the second separator is arranged between the first side of the anode pole piece and the cathode pole piece in a covering manner; any two adjacent surfaces of the anode pole piece as well as the surface of the first side and the inner side wall of the first concave part are respectively connected through a first arc transition surface. According to the battery monomer, the relative position between the anode pole piece and the cathode pole piece can be limited, the pole piece deflection is reduced, the pole piece alignment degree is improved, the lithium precipitation risk is reduced, the damage to the battery core assembly is reduced, and the diaphragm tearing risk is reduced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to battery cells, battery devices and electrical devices. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development. The battery cell in the battery is usually stacked by anode pole pieces, diaphragms and cathode pole pieces. In the related technology, the stacked battery cells are prone to pole piece deflection during the transportation process before hot pressing, causing the battery cell size to exceed the design requirements, making it difficult for the subsequent battery cell to enter the shell, which is easy to cause damage to the battery cell, and the risk of lithium plating in the battery cell increases, resulting in a decrease in battery performance. Utility Model Content

[0003] In view of the above problems, the present application provides a battery cell, a battery device and an electrical device, which can improve the problem of pole piece deflection.

[0004] In a first aspect, the present application provides a battery cell, comprising a cell assembly, the cell assembly comprising a plurality of lamination units stacked along the thickness direction of the cell assembly; the lamination units comprising: an anode pole sheet, the anode pole sheet having a first side and a second side arranged opposite to each other in the thickness direction of the anode pole sheet, the first side of the anode pole sheet being recessed with a first recess; a cathode pole sheet embedded in the first recess; a first insulating member covering the second side of the anode pole sheet; a second insulating member covering the first side of the anode pole sheet and between the cathode pole sheet; wherein any two adjacent surfaces of the anode pole sheet and the surface of the first side and the inner side wall of the first recess are connected respectively by a first arc transition surface.

[0005] In the technical solution of the embodiment of the present application, by arranging the cathode pole piece to be integrally embedded in the first recessed portion of the anode pole piece, the relative position between the anode pole piece and the cathode pole piece can be limited, thereby reducing the pole piece deflection, improving the problem of pole piece deflection, and improving the reliability and stability of the battery cell assembly. The alignment between the cathode pole piece and the anode pole piece can also be improved, thereby improving the dimensional accuracy of the battery cell assembly, facilitating the insertion of the battery cell assembly into the shell, which is beneficial to reducing the damage to the battery cell assembly, and can also reduce the risk of lithium plating, and is beneficial to improving the charging and discharging performance of the battery cell assembly, improving the fast charging capability, and extending the cycle life, thereby improving The safety and performance of the battery cell; by arranging the first arc transition surface between any two adjacent surfaces of the anode pole piece and between the surface of the first side and the inner wall of the first recess respectively, the sharp edges and corners on the anode pole piece are reduced, and the situation where the pole piece hits the right angle and causes damage to the pole piece can be reduced, and the damage to the battery cell assembly can be further reduced. The risk of puncture damage to the first and second isolation members can also be reduced, and the risk of tearing the diaphragm when the diaphragm is pulled is reduced, which is beneficial to reduce the risk of short circuit between the anode pole piece and the cathode pole piece, and further improve the safety and stability of the battery cell.

[0006] In some embodiments, a second concave portion is recessed on the bottom wall of the first concave portion, and a convex portion is protruded on one side of the cathode electrode piece toward the bottom wall of the first concave portion, and the convex portion is embedded in the second concave portion. By arranging the convex portion of the cathode electrode piece to be embedded in the second concave portion of the anode electrode piece to form a nested structure, the relative area between the cathode electrode piece and the anode electrode piece can be increased, the energy density of the battery cell assembly can be improved, and the efficiency of lithium ion insertion and extraction can be improved, which is conducive to improving the charging and discharging efficiency of the battery cell assembly, thereby improving the charging and discharging performance of the battery cell.

[0007] In some embodiments, the inner side wall of the second concave portion is connected to the bottom wall of the first concave portion by a second arc transition surface; any two adjacent surfaces of the convex portion are connected by a third arc transition surface. In this way, the sharp edges and corners of the convex portion and the second concave portion are reduced, which can reduce the occurrence of pole piece collision at right angles and damage to the pole piece, reduce damage to the battery cell assembly, and reduce the risk of puncture damage to the second separator, reduce the risk of tearing the diaphragm when the diaphragm is pulled, which is conducive to reducing the risk of short circuit between the anode pole piece and the cathode pole piece, and improving the safety and stability of the battery cell.

[0008] In some embodiments, the second separator also covers two opposite sides of the anode electrode sheet in a first direction, wherein the first direction is perpendicular to the thickness direction of the anode electrode sheet. This helps to better separate the anode electrode sheet from the cathode electrode sheet, reduces the risk of short circuit between the anode electrode sheet and the cathode electrode sheet, and helps to improve the safety of the battery cell.

[0009] In some embodiments, the first separator and the second separator both have a head end and a tail end arranged opposite to each other in the first direction; wherein the tail end of the first separator is integrally connected to the head end of the second separator; and / or, the tail end of the second separator of one laminate unit is integrally connected to the head end of the first separator of another adjacent laminate unit. In this arrangement, the first separator and the second separator are an integrated diaphragm, which can reduce the cutting steps of the diaphragm, which is conducive to simplifying the manufacturing process of the battery cell assembly, improving production efficiency, reducing costs, and is conducive to improving the isolation effect of the anode pole piece and the cathode pole piece, reducing the risk of short circuit between the anode pole piece and the cathode pole piece, and improving the safety of the battery cell.

[0010] In some embodiments, the thickness of the cathode electrode piece is less than or equal to the depth of the first concave portion. In this way, the occurrence of electrode piece collision at right angles and resulting in electrode piece damage can be reduced, further reducing damage to the battery cell assembly, and also reducing the risk of tearing the diaphragm when the diaphragm is pulled, further improving the safety and stability of the battery cell.

[0011] In some embodiments, the plurality of laminate units include an outer laminate unit, the first side of the anode electrode sheet of the outer laminate unit is arranged away from the other laminate units; the battery cell assembly also includes a third separator, the third separator covers the anode electrode sheet and the cathode electrode sheet arranged in the outer laminate unit. In this way, it is helpful to improve the isolation effect of the anode electrode sheet and the cathode electrode sheet, reduce the risk of short circuit between the anode electrode sheet and the cathode electrode sheet, and improve the safety of the battery cell.

[0012] In some embodiments, a plurality of laminated units form a stacked body; the battery cell assembly further comprises a first adhesive member, and the first adhesive member is attached to at least one side of the stacked body in a first direction, wherein the first direction is perpendicular to the thickness direction of the battery cell assembly; and / or the battery cell assembly further comprises a second adhesive member, and the second adhesive member is attached to at least one side of the stacked body in the thickness direction of the battery cell assembly. By providing the first adhesive member and / or the second adhesive member, the multi-layer laminated unit after lamination can be fixed, which is conducive to reducing the deflection of the pole piece, facilitating the subsequent hot pressing by a hot press to form a complete battery cell assembly, and is conducive to improving the structural stability and reliability of the battery cell assembly.

[0013] In a second aspect, the present application provides a battery device, which includes the battery cell in the above embodiment.

[0014] In a third aspect, the present application provides an electrical device, which includes the battery device in the above embodiment, and the battery device is used to provide electrical energy.

[0015] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of a vehicle according to some embodiments of the present application.

[0018] Figure 2 Schematic diagram of the exploded structure of a battery device according to some embodiments of the present application.

[0019] Figure 3 This is a schematic diagram of the exploded structure of a battery cell according to some embodiments of the present application.

[0020] Figure 4 This is a schematic diagram of the structure of the battery cell assembly of some embodiments of the present application.

[0021] Figure 5 This is a schematic diagram of the structure of the lamination unit of some embodiments of the present application.

[0022] Figure 6 A schematic diagram of the structure of a plurality of lamination units stacked in some embodiments of the present application.

[0023] Figure 7 A schematic diagram of the structure of a plurality of lamination units stacked in some other embodiments of the present application.

[0024] Figure 8 A schematic diagram of the structure of a plurality of lamination units stacked in some other embodiments of the present application.

[0025] The reference numerals in the specific implementation manner are as follows:

[0026] 1000, vehicle; 100, battery device; 200, controller; 300, motor;

[0027] 10. Box body; 11. First part; 12. Second part;

[0028] 20. Battery cell; 21. End cap; 211. Electrode terminal; 22. Shell; 23. Cell assembly; 230. Lamination unit; 230a. Outer lamination unit; 231. Tab; 232. Anode pole piece; 2321. First recess; 2322. First arc transition surface; 2323. Second recess; 2324. Second arc transition surface; 233. Cathode pole piece; 2331. Protrusion; 2332. Third arc transition surface; 234. First isolating member; 235. Second isolating member; 236. Third isolating member; 237. First adhesive member; 238. Second adhesive member; 24. External insulating member. DETAILED DESCRIPTION

[0029] The specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0030] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0032] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0033] In the description of the embodiments of the present application, it needs to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0034] In the description of the embodiments of the present application, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. Thus, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the embodiments of the present application, the meaning of "plurality" is at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0035] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0036] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0037] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. An element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and are not intended to be the only implementation method.

[0038] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0039] The battery cell is usually stacked with anode plates, separators and cathode plates, and the anode plates and cathode plates are separated by separators. In the related art, the cathode and cathode plates of the laminated battery cell are stacked on the separator, which has poor stability. The plates of the laminated battery cell are easy to move during the transportation from the stacking table to the hot press, causing the plates to be skewed, which in turn causes the battery cell size to exceed the design requirements, making it difficult for the subsequent battery cell to enter the shell, and easily causing damage to the battery cell; and the risk of lithium deposition in the battery cell increases, which will lead to a decrease in battery performance, shorten the cycle life, and limit the fast charging capability. In addition, lithium deposition may also cause safety hazards such as combustion and explosion.

[0040] In order to improve the problem of pole piece deflection, a nested cell structure has emerged, in which the anode pole piece and the cathode pole piece are nested with each other through grooves and bosses to improve the stability of the cell. However, in the stacked cell structure, the pole piece has edges and corners, and the pole piece is prone to hit the right angle during the transportation of the stacked cell, causing damage to the pole piece, which is particularly serious in the nested cell structure; at the same time, when the diaphragm in the stacked cell swings, the edges and corners of the grooves of the anode pole piece or the cathode pole piece are easy to scratch the diaphragm, causing the diaphragm to tear when it is pulled, affecting the performance of the cell.

[0041] Based on the above considerations, in order to improve the problem of pole piece deflection, a battery cell assembly is designed. Based on the nested battery cell structure with the anode pole piece concave, the edges and each sharp corner position of the concave structure of the anode pole piece are set as a circular arc chamfer structure. In such a battery cell assembly, the pole piece deflection can be reduced, the alignment of the cathode pole piece and the anode pole piece can be improved, and the problem of edge impact can be improved, reducing the damage to the battery cell. In addition, the diaphragm is not easy to tear when it is pulled, which is conducive to improving the stability of the stacked battery cell structure, thereby improving battery performance.

[0042] The battery cell assembly disclosed in the embodiment of the present application can be used in a battery cell, and the battery cell can be used in, but not limited to, a power device such as a vehicle, a ship, or an aircraft. A power supply system having the battery cell and the battery device disclosed in the present application can be used to form the power device, which is conducive to improving the stability of the battery cell and the battery device, and further improving the performance of the battery cell and the battery device.

[0043] The embodiment of the present application provides an electric device using a battery device as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0044] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0045] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery device 100 may be used to power the vehicle 1000, for example, the battery device 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0046] In some embodiments of the present application, the battery device 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0047] Please refer to Figure 2 , Figure 2Schematic diagram of the exploded structure of the battery device 100 provided in some embodiments of the present application. The battery device 100 includes a box 10 and a battery cell 20, and the battery cell 20 is contained in the box 10. Among them, the box 10 is used to provide a storage space for the battery cell 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one end open, the first part 11 can be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0048] In the battery device 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery device 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery device 100 may also include other structures, for example, the battery device 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0049] Each battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0050] Please refer to Figure 3 , Figure 3 The schematic diagram of the exploded structure of the battery cell 20 provided in some embodiments of the present application. The battery cell 20 refers to the smallest unit constituting the battery device 100. Figure 3 As shown, the battery cell 20 includes an end cover 21, a housing 22, a battery cell assembly 23 and other functional components.

[0051] The end cap 21 refers to a component that covers the opening of the shell 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 can be adapted to the shape of the shell 22 to match the shell 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 21 is not easy to deform when it is squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 211 can be provided on the end cap 21. The electrode terminal 211 can be used to electrically connect with the battery cell assembly 23 to output or input the electrical energy of the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this. In some embodiments, an insulating member may be provided inside the end cap 21, and the insulating member may be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0052] The shell 22 is a component used to cooperate with the end cover 21 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the battery cell assembly 23, electrolyte and other components. The shell 22 and the end cover 21 can be independent components, and an opening can be set on the shell 22, and the internal environment of the battery cell 20 is formed by covering the opening with the end cover 21 at the opening. Without limitation, the end cover 21 and the shell 22 can also be integrated. Specifically, the end cover 21 and the shell 22 can form a common connection surface before other components are put into the shell, and when the interior of the shell 22 needs to be encapsulated, the end cover 21 covers the shell 22. The shell 22 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 22 can be determined according to the specific shape and size of the battery cell assembly 23. The material of the shell 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0053] The battery cell assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more battery cell assemblies 23 may be contained in the housing 22. The battery cell assembly 23 is mainly formed by stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active substances constitute the main body of the battery cell assembly, and the parts of the positive and negative electrode sheets without active substances each constitute a tab 231. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active substance and the negative active substance react with the electrolyte, and the tab 231 connects the electrode terminals to form a current loop.

[0054] The battery cell 20 may further include an external insulating member 24, which may wrap the cell assembly 23, and may space the shell 22 and the cell assembly 23 to achieve insulation protection for the cell assembly 23. The external insulating member 24 may include an insulating film, which may be folded to form a top-opening box body that is substantially the same shape as the shell 22, but slightly smaller in size. For example, the shell 22 is in the shape of a rectangular parallelepiped, and the external insulating member 24 is folded to form a top-opening rectangular box body that is adapted to the size of the cell assembly 23; the cell assembly 23 is first loaded into the folded external insulating member 24, and then loaded into the shell 22 together with the external insulating member 24, so that the external insulating member 24 spaces the cell assembly 23 from the shell 22. The external insulating member 24 may be made of PP (polypropylene) or PET (polyethylene terephthalate), such as Mylar, a tough polyester polymer that has good heat resistance, excellent electrical insulation, and even good electrical performance at high temperature and high frequency.

[0055] According to some embodiments of the present application, referring to Figures 3 to 5 , Figure 4 This is a schematic diagram of the structure of a battery cell assembly 23 provided in some embodiments of the present application. Figure 5A schematic diagram of the structure of a laminate unit 230 provided for some embodiments of the present application. An embodiment of the present application provides a battery cell 20. The battery cell 20 includes a cell assembly 23. The cell assembly 23 includes a plurality of laminate units 230 stacked along the thickness direction Z of the cell assembly 23. The laminate unit 230 includes an anode pole piece 232, a cathode pole piece 233, a first separator 234 and a second separator 235. The anode pole piece 232 has a first side and a second side that are arranged opposite to each other in the thickness direction of the anode pole piece 232, and the first side of the anode pole piece 232 is recessed with a first recess 2321. The cathode pole piece 233 is embedded in the first recess 2321. The first separator 234 is arranged to cover the second side of the anode pole piece 232. The second separator 235 is arranged to cover between the first side of the anode pole piece 232 and the cathode pole piece 233. Any two adjacent surfaces of the anode electrode sheet 232 and the surface of the first side and the inner wall of the first recess 2321 are connected via the first arc transition surface 2322 .

[0056] like Figures 3 to 5 As shown in , the X direction indicates the first direction, which is the width direction of the battery cell assembly 23, the Y direction indicates the second direction, which is the height direction of the battery cell assembly 23, and the Z direction is the thickness direction of the battery cell assembly 23, and the X direction, the Y direction and the Z direction are perpendicular to each other.

[0057] The battery cell assembly 23 is a laminated battery cell structure, and the thickness direction of the laminated unit 230, the thickness direction of the anode electrode sheet 232, and the thickness direction of the cathode electrode sheet 233 are all along the thickness direction Z of the battery cell assembly 23. Multiple laminated units 230 are stacked in sequence along the thickness direction Z of the battery cell assembly 23, that is, the stacking direction of the laminated units 230 is along the thickness direction Z of the battery cell assembly 23. Multiple laminated units 230 form a stacked body.

[0058] In each laminate unit 230, the anode electrode 232 can lose electrons and undergo an oxidation reaction, has a low potential, and is a negative electrode; the cathode electrode 233 can obtain electrons and undergo a reduction reaction, has a high potential, and is a positive electrode. The anode electrode 232 and the cathode electrode 233 in each laminate unit 230 are separated by a second separator 235, and two adjacent laminate units 230 are separated by a first separator 234.

[0059] Among them, the anode electrode sheet 232 includes a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer is coated on the surface of the negative electrode current collector, the negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector not coated with the negative electrode active material layer constitutes a negative electrode tab. The negative electrode active material can be silicon-carbon material / negative electrode lithium metal / stainless steel material / hard carbon material / nanosilver material, etc. Taking lithium-ion batteries as an example, the negative electrode current collector can be copper foil, and the negative electrode active material can be carbon or silicon, etc. After the negative electrode active material is stirred and mixed, a negative electrode slurry is obtained, and then the negative electrode slurry is coated on the surface of the negative electrode current collector, and after baking and drying, cold pressing, pre-cutting, striping and other processes are carried out to prepare the anode electrode sheet 232.

[0060] The cathode electrode sheet 233 includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer. The positive electrode current collector not coated with the positive electrode active material layer constitutes a positive electrode tab. The positive electrode active material can be a ternary material / lithium iron phosphate material+sulfide / halide / oxide / polymer solid electrolyte, etc. Taking lithium-ion batteries as an example, the positive electrode current collector can be aluminum foil, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The positive electrode active material is stirred and mixed to obtain a positive electrode slurry, and then the positive electrode slurry is coated on the surface of the positive electrode current collector, and after baking and drying, cold pressing (rolling), pre-slitting, slitting and other processes are performed to prepare the cathode electrode sheet 233.

[0061] The materials of the first spacer 234 and the second spacer 235 can be the same or different, and there is no limitation here. The first spacer 234 and the second spacer 235 can be at least one of glass fiber cloth, non-woven fabric, polypropylene (PP) film and polyethylene (PE) film. The first spacer 234 and the second spacer 235 can be a single-layer film or a multi-layer composite film, and there is no limitation here.

[0062] The first side and the second side of the anode electrode sheet 232 are arranged opposite to each other along the thickness direction of the anode electrode sheet 232, and the negative electrode active material layer is arranged at least on the first side surface of the anode electrode sheet 232. The first sides of the anode electrode sheets 232 of the plurality of stacked units 230 have the same orientation along the thickness direction Z of the battery cell assembly 23, that is, the orientation of the first side of each anode electrode sheet 232 is the same. The first recess 2321 can be formed by being recessed on the negative electrode active material layer on the first side of the anode electrode sheet 232 along the thickness direction of the anode electrode sheet 232. The first recess 2321 can be formed when the negative electrode active material layer is applied, or can be formed by etching, cutting, etc. after the negative electrode active material layer is applied. The first recess 2321 has an opening, a bottom wall arranged opposite to the opening in the thickness direction of the anode electrode sheet 232, and an inner side wall connected between the bottom wall and the surface of the first side of the anode electrode sheet 232, and the bottom wall and the inner side wall constitute the inner wall of the first recess 2321.

[0063] The cross-sectional shape of the first recess 2321 on the surface perpendicular to the thickness direction of the anode electrode piece 232 is adapted to the shape of the cathode electrode piece 233, so that the cathode electrode piece 233 can be embedded in the first recess 2321. For example, the shape of the cathode electrode piece 233 may include but is not limited to square, rectangular, semicircular, elliptical, circular or triangular. The cathode electrode piece 233 is located in the first recess 2321 as a whole, and part of the second isolation member 235 is clamped between the cathode electrode piece 233 and the inner wall of the first recess 2321. In some embodiments, the bottom wall of the first recess 2321 may be an arc surface, and the surface of the cathode electrode piece 233 facing the bottom wall of the first recess 2321 is an arc surface; the bottom wall of the first recess 2321 may also be a plane, and the surface of the cathode electrode piece 233 facing the bottom wall of the first recess 2321 is a plane; no specific limitation is made here.

[0064] The stacking unit 230 forms a nested structure, which can limit the relative position between the anode electrode sheet 232 and the cathode electrode sheet 233, reduce the mutual movement between the cathode electrode sheet 233 and the anode electrode sheet 232, and reduce the electrode sheet deflection, thereby improving the reliability and stability of the battery cell assembly 23; and the stacking and alignment operation of the anode electrode sheet 232 and the cathode electrode sheet 233 is convenient, which can improve the alignment of the cathode electrode sheet 233 and the anode electrode sheet 232, thereby improving the dimensional accuracy of the battery cell assembly 23, facilitating the subsequent insertion of the battery cell assembly 23 into the shell, reducing the extrusion of the battery cell assembly 23, and helping to reduce the damage to the battery cell assembly 23.

[0065] Since the cathode electrode piece 233 is integrally embedded in the first recess 2321 of the anode electrode piece 232, the area of ​​the anode electrode piece 232 can be made larger than the area of ​​the cathode electrode piece 233, thereby at least meeting the lower limit requirement of the battery Overhang size (OH size for short). The Overhang size refers to the portion of the anode electrode piece 232 that exceeds the cathode electrode piece 233 in a direction perpendicular to the thickness direction. By setting the size of the anode electrode piece 232 to have a certain excess compared to the size of the cathode electrode piece 233, the probability of lithium deposition at the edge of the electrode piece can be reduced, the precipitation of lithium dendrites can be reduced, and potential safety hazards can be reduced, thereby improving the safety of the battery cell assembly 23, and it is beneficial to improve the charging and discharging performance of the battery cell assembly 23, enhance the fast charging capability, and extend the cycle life, thereby improving the performance of the battery cell assembly 23.

[0066] Meanwhile, the anode electrode piece 232 may have at least five surfaces, namely, the surface of the first side, the surface of the second side, and at least three side surfaces connected between the surface of the first side and the surface of the second side. Any two adjacent surfaces of the anode electrode piece 232 are connected by the first arc transition surface 2322, which means that the surface of the first side is connected to any one of the at least three side surfaces by the first arc transition surface 2322, the surface of the second side is connected to any one of the at least three side surfaces by the first arc transition surface 2322, and any two adjacent side surfaces of the at least three side surfaces are connected by the first arc transition surface 2322. The surface of the first side is connected to the inner side wall of the first recess 2321 by the first arc transition surface 2322, which means that the surface of the first side is connected to any inner side wall of the first recess 2321 by the first arc transition surface 2322. Among them, the first arc transition surface 2322 may be a convex arc surface.

[0067] Such arrangement enables the boundaries and corner positions of each surface of the anode pole piece 232 and the opening position of the first recess 2321 to form a circular arc chamfer structure, reducing the sharp edges and corners on the anode pole piece 232, and reducing the situation where the pole piece hits the right angle position and causes the pole piece to be damaged, which is beneficial to reducing the damage to the battery cell assembly 23; and can reduce the risk of puncturing and damaging the first separator 234 and the second separator 235, and the diaphragm is not easy to scratch the diaphragm when swinging, reducing the risk of tearing the diaphragm when pulling the diaphragm, which is beneficial to reducing the risk of short circuit between the anode pole piece 232 and the cathode pole piece 233, thereby improving the safety and stability of the battery cell assembly 23. In addition, the structure of the battery cell assembly 23 is simple, which can simplify the manufacturing process and reduce costs.

[0068] The battery cell 20 of the embodiment of the present application can limit the relative position between the anode electrode piece 232 and the cathode electrode piece 233 by setting the cathode electrode piece 233 as a whole embedded in the first recess 2321 set in the anode electrode piece 232, thereby reducing the electrode piece deflection, improving the problem of electrode piece deflection, and improving the reliability and stability of the battery cell assembly 23. It can also improve the alignment between the cathode electrode piece 233 and the anode electrode piece 232, thereby improving the dimensional accuracy of the battery cell assembly 23, facilitating the insertion of the battery cell assembly 23 into the shell, which is beneficial to reducing the damage to the battery cell assembly 23, and can also reduce the risk of lithium precipitation, and is beneficial to improving the charging and discharging performance of the battery cell assembly 23, improving the fast charging capability, and extending the cycle life, thereby improving The safety and performance of the battery cell 20; by setting the first arc transition surface 2322 between any two adjacent surfaces of the anode pole piece 232 and between the surface of the first side and the inner wall of the first recess 2321, the sharp edges and corners on the anode pole piece 232 are reduced, and the situation where the pole piece hits the right angle and causes damage to the pole piece can be reduced, and the damage to the battery cell assembly 23 can be further reduced. The risk of puncture damage to the first isolation member 234 and the second isolation member 235 is reduced, and the risk of tearing the diaphragm when the diaphragm is pulled is reduced, which is beneficial to reduce the risk of short circuit between the anode pole piece 232 and the cathode pole piece 233, and further improve the safety and stability of the battery cell 20.

[0069] In some embodiments, reference Figure 6 , Figure 6 A schematic diagram of a structure in which a plurality of lamination units 230 are stacked and arranged in some embodiments of the present application, wherein a second recess 2323 is recessed on the bottom wall of the first recess 2321. A convex portion 2331 is protruded from one side of the cathode electrode 233 toward the bottom wall of the first recess 2321, and the convex portion 2331 is embedded in the second recess 2323.

[0070] The second recess 2323 may be formed by being recessed on the negative electrode active material layer on the bottom wall of the first recess 2321 along the thickness direction of the anode electrode sheet 232. The second recess 2323 may be formed when the negative electrode active material layer is applied, or may be formed by etching, cutting, etc. after the negative electrode active material layer is applied. The second recess 2323 also has an opening, a bottom wall arranged opposite to the opening in the thickness direction of the anode electrode sheet 232, and an inner side wall of the second recess 2323 connected between the bottom wall of the second recess 2323 and the bottom wall of the first recess 2321. The bottom wall and the inner side wall of the second recess 2323 constitute the inner wall of the second recess 2323.

[0071] The convex portion 2331 may be formed by the positive electrode active material layer on the surface of the cathode electrode piece 233 facing the bottom wall of the first concave portion 2321 along the thickness direction of the cathode electrode piece 233. The convex portion 2331 may be formed when the positive electrode active material layer is applied, or may be formed by etching, cutting, etc. after the positive electrode active material layer is applied. The cross-sectional shape of the second concave portion 2323 on the surface perpendicular to the thickness direction of the anode electrode piece 232 is adapted to the cross-sectional shape of the convex portion 2331 on the surface perpendicular to the thickness direction of the cathode electrode piece 233, so that the convex portion 2331 can be embedded in the second concave portion 2323. For example, the cross-sectional shape of the convex portion 2331 on the surface perpendicular to the thickness direction of the cathode electrode piece 233 may include, but is not limited to, square, rectangular, semicircular, elliptical, circular, or triangular. The protrusion 2331 is located in the second recess 2323 , and a portion of the second isolation member 235 is further clamped between the protrusion 2331 and the inner wall of the second recess 2323 .

[0072] In some embodiments, a plurality of second recesses 2323 may be arranged at intervals on the bottom wall of the first recess 2321 , and a plurality of protrusions 2331 may be arranged on the cathode electrode piece 233 corresponding to the plurality of second recesses 2323 .

[0073] By arranging the convex portion 2331 of the cathode electrode sheet 233 to be embedded in the second concave portion 2323 of the anode electrode sheet 232 to form a nested structure, the relative area between the cathode electrode sheet 233 and the anode electrode sheet 232 can be increased, the energy density of the battery cell assembly 23 can be improved, and the efficiency of lithium ion insertion and extraction can be improved, which is beneficial to improving the charging and discharging efficiency of the battery cell assembly 23, thereby improving the charging and discharging performance of the battery cell 20.

[0074] In some embodiments, reference Figure 6 The inner side wall of the second concave portion 2323 is connected to the bottom wall of the first concave portion 2321 via a second arc transition surface 2324. Any two adjacent surfaces of the convex portion 2331 are connected via a third arc transition surface 2332.

[0075] The inner side wall of the second concave portion 2323 is connected to the bottom wall of the first concave portion 2321 through the second arc transition surface 2324, which means that the bottom wall of the first concave portion 2321 is connected to the inner side wall of any second concave portion 2323 through the second arc transition surface 2324. The convex portion 2331 may have at least four surfaces, namely, the end surface of the convex portion 2331 facing the second concave portion 2323 and at least three side surfaces connected to the end surface. Any two adjacent surfaces of the convex portion 2331 are connected through the third arc transition surface 2332, which means that the end surface is connected to any one of the at least three side surfaces through the third arc transition surface 2332, and any two adjacent side surfaces of the at least three side surfaces are connected through the third arc transition surface 2332. Among them, the second arc transition surface 2324 and the third arc transition surface 2332 may be convex arc surfaces.

[0076] By setting the inner wall of the second recess 2323 and the bottom wall of the first recess 2321 to be connected by the second arc transition surface 2324, and any two adjacent surfaces of the protrusion 2331 to be connected by the third arc transition surface 2332, the sharp edges and corners of the protrusion 2331 and the second recess 2323 are reduced, which can reduce the situation where the pole piece hits the right angle and causes damage to the pole piece, reduce the damage to the battery cell assembly 23, and can also reduce the risk of puncture damage to the second isolation piece 235, reduce the risk of tearing the diaphragm when the diaphragm is pulled, and improve the safety and stability of the battery cell 20.

[0077] In some embodiments, reference Figures 4 to 8 , Figure 7 A schematic diagram of a structure in which a plurality of lamination units 230 are stacked and arranged in accordance with other embodiments of the present application is provided. Figure 8 A schematic structural diagram of a plurality of stacked lamination units 230 provided in some other embodiments of the present application, wherein the second isolation member 235 also covers opposite sides of the anode pole piece 232 in a first direction X, wherein the first direction X is perpendicular to the thickness direction of the anode pole piece 232 .

[0078] The first direction X may be the width direction of the anode electrode sheet 232, and the second direction Y may be the height direction of the anode electrode sheet 232. In this way, the second separator 235 cooperates with the first separator 234 to cover the two opposite sides in the thickness direction and the two opposite sides in the width direction of the anode electrode sheet 232. In some embodiments, the size of the first separator 234 and the second separator 235 in the height direction of the battery cell assembly 23 (i.e., the second direction Y) is greater than the height of the anode electrode sheet 232, and the second separator 235 cooperates with the first separator 234 to cover the two opposite sides in the height direction of the anode electrode sheet 232, so that the anode electrode sheet 232 is covered by the first separator 234 and the second separator 235 in all directions.

[0079] Providing the second isolation member 235 to cover the two opposite sides of the anode electrode sheet 232 in the width direction is beneficial to better separate the anode electrode sheet 232 from the cathode electrode sheet 233 , reducing the risk of short circuit between the anode electrode sheet 232 and the cathode electrode sheet 233 , and improving the safety of the battery cell 20 .

[0080] In some embodiments, reference Figure 7 , the first separator 234 and the second separator 235 can be independent of each other. The lamination process of the battery cell assembly 23 may include: moving and placing a separator of a first length along the first direction X, fixing the separator by a mechanical press plate and then cutting to obtain the first separator 234, wherein the first length is greater than the width of the anode electrode sheet 232; then placing the anode electrode sheet 232 on the first separator 234; then continuing to move in the opposite direction of the first direction X to place a separator of a second length, the separator covers the anode electrode sheet 232 and the first separator 234, wherein the second length is greater than the first length, for example, the second length can be twice the first length; placing the cathode electrode sheet 233 in the first recess 2321, part of the separator is clamped between the cathode electrode sheet 233 and the inner wall of the first recess 2321, and then cutting the separator to obtain the second separator 235, the first separator 234, the anode electrode sheet 232, the second separator 235 and the cathode electrode sheet 233 together form a lamination unit 230. Another first isolating member 234 is continuously placed on the lamination unit 230 along the first direction X to form another lamination unit 230 . This cycle is repeated to complete the lamination process of the battery cell assembly 23 .

[0081] In some embodiments, reference Figures 4 to 8 The first isolating member 234 and the second isolating member 235 both have a head end and a tail end that are oppositely disposed in the first direction X. Figures 4 to 6 and Figure 8 , the tail end of the first isolating member 234 is integrally connected to the head end of the second isolating member 235; and / or, the tail end of the second isolating member 235 of one laminate unit 230 is integrally connected to the head end of the first isolating member 234 of another adjacent laminate unit 230.

[0082] The tail end of the first separator 234 in each lamination unit 230 may be integrally connected with the head end of the second separator 235, that is, the first separator 234 and the second separator 235 are two parts of the same separator. At this time, the lamination process of the lamination unit 230 may include: moving along the first direction X to place a separator of a first length, fixing the separator by a mechanical pressing plate, and then placing the anode electrode sheet 232, and continuing to move in the opposite direction of the first direction X to place a separator of a third length to cover the anode electrode sheet 232, wherein the third length is greater than the second length, and the second length is greater than the first length, for example, the third length may be three times the first length; placing the cathode electrode sheet 233 in the first recess 2321, and then swinging and pulling the separator along the first direction X to shorten the length of the separator covering the first side of the anode electrode sheet 232 to the second length, and then cutting the separator, so that a part of the separator covering the second side of the anode electrode sheet 232 forms the first separator 234, and the remaining other part of the separator forms the second separator 235. In this way, the lamination process of the lamination unit 230 is completed.

[0083] Alternatively, the tail end of the second separator 235 of one lamination unit 230 may be integrally connected to the head end of the first separator 234 of another adjacent lamination unit 230, that is, the same separator is used between two adjacent lamination units 230 to form the first separator 234 and the second separator 235. At this time, the lamination process of the battery cell assembly 23 may include: after placing the anode electrode sheet 232 on the first separator 234, continue to move along the first direction X to place a separator of the second length, and the separator covers the anode electrode sheet 232 and the first separator 234; place the cathode electrode sheet 233 in the first recess 2321, and then continue to move in the opposite direction of the first direction X to place another separator of the first length, and the separator covers the cathode electrode sheet 233, thereby obtaining the first separator 234 of another lamination unit 230. This cycle is repeated to complete the lamination process of the battery cell assembly 23.

[0084] It is also possible that the tail end of the first isolation member 234 in each stacking unit 230 is integrally connected to the head end of the second isolation member 235, and at the same time, the tail end of the second isolation member 235 of one stacking unit 230 is integrally connected to the head end of the first isolation member 234 of another adjacent stacking unit 230. That is to say, one diaphragm can be used to simultaneously form multiple first isolation members 234 and multiple second isolation members 235 of the battery cell assembly 23. At this time, the lamination process of the battery cell assembly 23 may include: moving along the first direction X to place a diaphragm of a first length, fixing the diaphragm by a mechanical pressing plate, and then placing an anode electrode sheet 232, and continuing to move in the opposite direction of the first direction X to place a diaphragm of a third length to cover the anode electrode sheet 232; placing the cathode electrode sheet 233 in the first recess 2321, and then swinging and pulling the diaphragm along the first direction X to shorten the length of the diaphragm covering the first side of the anode electrode sheet 232 to the second length, so that a portion of the diaphragm covering the second side of the anode electrode sheet 232 forms a first separator 234, and a portion of the diaphragm covering the first side of the anode electrode sheet 232 forms a second separator 235; and then continuing to move in the opposite direction of the first direction X again to place another diaphragm of the first length, and the diaphragm covers the cathode electrode sheet 233, so as to obtain the first separator 234 of another lamination unit 230. This cycle is repeated to complete the lamination process of the battery cell assembly 23.

[0085] By setting the first isolation member 234 and the second isolation member 235 as an integrated diaphragm, the steps of cutting the diaphragm can be reduced, which is beneficial to simplifying the manufacturing process of the battery cell assembly 23, improving production efficiency, and reducing costs. It is also beneficial to improve the isolation effect between the anode electrode piece 232 and the cathode electrode piece 233, reduce the risk of short circuit between the anode electrode piece 232 and the cathode electrode piece 233, and improve the safety of the battery cell 20.

[0086] In some embodiments, the thickness of the cathode electrode 233 is less than or equal to the depression depth of the first recess 2321 .

[0087] The thickness direction of the cathode electrode sheet 233 is along the thickness direction Z of the battery cell assembly 23. The first recess 2321 is arranged to be recessed along the thickness direction of the anode electrode sheet 232 (ie, the thickness direction Z of the battery cell assembly 23).

[0088] Since the thickness of the cathode electrode sheet 233 is less than or equal to the depression depth of the first recess 2321, the cathode electrode sheet 233 is located entirely in the first recess 2321, which can reduce the height of the cathode electrode sheet 233 protruding from the first side of the anode electrode sheet 232. Therefore, the anode electrode sheet 232 is not easy to hit the cathode electrode sheet 233 during the stacking process of the battery cell assembly 23, and the cathode electrode sheet 233 is not easy to scratch the second isolation piece 235 when the second isolation piece 235 is pulled.

[0089] In this way, the occurrence of pole piece damage caused by hitting the right angle position can be reduced, and the damage to the battery cell assembly 23 can be further reduced. The risk of tearing the diaphragm when pulling the diaphragm can also be reduced, and the safety and stability of the battery cell 20 can be further improved.

[0090] In some embodiments, reference Figure 4 The plurality of lamination units 230 include an outer lamination unit 230a, and the first side of the anode electrode sheet 232 of the outer lamination unit 230a is arranged away from the other lamination units 230. The battery cell assembly 23 also includes a third separator 236, and the third separator 236 covers the anode electrode sheet 232 and the cathode electrode sheet 233 arranged on the outer lamination unit 230a.

[0091] The outer layer laminate unit 230a refers to the outermost laminate unit 230 of the laminated body formed by the multi-layer laminate units 230 along the thickness direction Z of the battery cell assembly 23, and the first side of the outer layer laminate unit 230a faces the outside of the laminated body of the multi-layer laminate units 230. That is, the first recess 2321 of the outer layer laminate unit 230a is located on the outside of the laminated body of the multi-layer laminate units 230, so that the side of the cathode electrode 233 away from the bottom wall of the first recess 2321 faces the outside of the laminated body of the multi-layer laminate units 230.

[0092] The material of the third isolating member 236 may be the same as or different from the material of the first isolating member 234 and the second isolating member 235, and there is no limitation here. The third isolating member 236 may be at least one of glass fiber cloth, non-woven fabric, polypropylene (PP) film and polyethylene (PE) film. The third isolating member 236 may be a single-layer film or a multi-layer composite film, and there is no limitation here. In some embodiments, the third isolating member 236 also has a head end and a tail end arranged opposite to each other in the first direction X, and the head end of the third isolating member 236 is integrally connected to the tail end of the second isolating member 235 of the outer laminate unit 230a.

[0093] By providing a third insulating member 236 to cover the anode electrode sheet 232 and the cathode electrode sheet 233 of the outer laminate unit 230a, it is beneficial to improve the isolation effect of the anode electrode sheet 232 and the cathode electrode sheet 233, reduce the risk of short circuit between the anode electrode sheet 232 and the cathode electrode sheet 233, and improve the safety of the battery cell 20.

[0094] In some embodiments, reference Figure 4 The plurality of laminate units 230 form a stacked body. The battery cell assembly 23 further includes a first adhesive member 237 , and the first adhesive member 237 is attached to at least one side of the stacked body in a first direction X, wherein the first direction X is perpendicular to a thickness direction Z of the battery cell assembly 23 .

[0095] The first adhesive member 237 can be attached and connected along the stacking direction of the laminated unit 230 (i.e., the thickness direction Z of the battery cell assembly 23), and can fix the laminated body of the laminated unit 230, so as to facilitate subsequent hot pressing by a hot press machine, thereby forming a complete battery cell assembly 23. For example, the first adhesive member 237 can include but is not limited to blue glue. In some embodiments, the first adhesive member 237 can be attached to both opposite sides of the laminated body in the first direction X.

[0096] In some embodiments, reference Figure 4 The battery cell assembly 23 further includes a second adhesive member 238 , and the second adhesive member 238 is adhered to at least one side of the stack in the thickness direction Z of the battery cell assembly 23 .

[0097] The second adhesive member 238 can further fix the stacked body of the multi-layer laminate unit 230. For example, the second adhesive member 238 can also include but is not limited to blue glue. In some embodiments, the second adhesive member 238 can be attached to both opposite sides of the stacked body in the thickness direction Z of the battery cell assembly 23.

[0098] By setting the first adhesive 237 and / or the second adhesive 238, the multi-layer laminated unit 230 can be fixed after lamination, which is beneficial to reduce the deflection of the pole pieces and facilitate the subsequent hot pressing by a hot press to form a complete battery cell assembly 23, which is beneficial to improve the structural stability and reliability of the battery cell assembly 23.

[0099] According to some embodiments of the present application, the present application further provides a battery device 100, and the battery device 100 includes the battery cell 20 provided in any of the above embodiments.

[0100] Since the battery device 100 has the same technical effects as the above-mentioned battery cell 20 , detailed description thereof will be omitted here.

[0101] According to some embodiments of the present application, the present application further provides an electric device, which includes the battery device 100 provided in any of the above embodiments, and the battery device 100 is used to provide electric energy for the electric device.

[0102] The power-consuming device may be any of the aforementioned devices or systems using the battery device 100. Since the power-consuming device has the same technical effects as the aforementioned battery device 100 and battery cell 20, they will not be described in detail here.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: The battery cell assembly comprises a plurality of laminate units stacked along a thickness direction of the battery cell assembly; The lamination unit comprises: an anode electrode sheet, the anode electrode sheet having a first side and a second side arranged opposite to each other in a thickness direction of the anode electrode sheet, the first side of the anode electrode sheet being recessed to form a first recess; A cathode electrode, embedded in the first recess; A first separator, covering and disposed on the second side of the anode electrode sheet; A second separator, covering and disposed between the first side of the anode electrode sheet and the cathode electrode sheet; Wherein, any two adjacent surfaces of the anode electrode sheet and the surface of the first side and the inner side wall of the first recess are connected respectively by a first arc transition surface.

2. The battery cell according to claim 1, characterized in that: A second recess is recessed on the bottom wall of the first recess, and a convex portion is protruding from one side of the cathode electrode sheet toward the bottom wall of the first recess, and the convex portion is embedded in the second recess.

3. The battery cell according to claim 2, characterized in that: The inner side wall of the second recess is connected to the bottom wall of the first recess via a second arc transition surface; any two adjacent surfaces of the protrusion are connected via a third arc transition surface.

4. The battery cell according to claim 1, characterized in that: The second separator also covers two opposite sides of the anode electrode sheet in a first direction, wherein the first direction is perpendicular to a thickness direction of the anode electrode sheet.

5. The battery cell according to claim 4, characterized in that: The first isolating member and the second isolating member each have a head end and a tail end that are oppositely disposed in the first direction; The tail end of the first isolating member is integrally connected to the head end of the second isolating member; and / or the tail end of the second isolating member of one of the laminated units is integrally connected to the head end of the first isolating member of another adjacent laminated unit.

6. The battery cell according to claim 1, characterized in that: The thickness of the cathode electrode plate is less than or equal to the depression depth of the first recess.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The plurality of lamination units include an outer lamination unit, wherein the first side of the anode electrode sheet of the outer lamination unit is arranged away from the other lamination units; The battery cell assembly further includes a third separator, which covers the anode electrode sheet and the cathode electrode sheet disposed on the outer layer lamination unit.

8. The battery cell according to any one of claims 1 to 6, characterized in that: A plurality of the lamination units form a laminated body; The battery cell assembly further includes a first adhesive member, and the first adhesive member is attached to at least one side of the stacked body in a first direction, wherein the first direction is perpendicular to a thickness direction of the battery cell assembly; And / or, the battery cell assembly further includes a second adhesive member, and the second adhesive member is adhered to at least one side of the stacked body in the thickness direction of the battery cell assembly.

9. A battery device, characterized in that: The battery device comprises the battery cell according to any one of claims 1 to 8.

10. An electrical device, characterized in that: The electrical device comprises the battery device as claimed in claim 9, and the battery device is used to provide electrical energy.

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