Electrode assembly and processing method and apparatus, battery cell, battery and power consuming device

Abstract

This application provides an electrode assembly and processing method and apparatus, a battery cell, a battery, and a power consumption device. The electrode assembly includes a cathode plate, an anode plate, and a separator, where the cathode plate is folded M times to form M folds in the folding region, a first adhesion region is formed on the inner surface of the Nth fold of the cathode plate, and a second adhesion region is formed on the outer surface of the Nth fold of the cathode plate; an ion-blocking layer, at least a portion of which is attached to the first adhesion region and which prevents ions released from the first adhesion region from being absorbed into the anode plate adjacent to the first adhesion region during charging; and a reinforcing layer, at least a portion of which is attached to the second adhesion region, which has ion exchange channels formed in the reinforcing layer, the ion exchange channels being through-holes arranged along the thickness direction of the reinforcing layer. An electrode cell having this structure can reduce lithium deposition and improve the capacity and safety of the battery cell.

Description

[Technical field]

[0001] The present application relates to the field of batteries, and in particular to electrode assemblies and processing methods and apparatus, battery cells, batteries and power consuming devices. [Background technology]

[0002] Battery cells are widely used in electronic devices, such as mobile phones, notebook computers, battery cars, electric cars, electric airplanes, electric steamships, electric car toys, electric steamship toys, electric airplane toys, electric tools, etc. The battery cells may include nickel-cadmium battery cells, nickel-metal hydride battery cells, lithium-ion battery cells, secondary alkaline zinc-manganese battery cells, etc.

[0003] In the development of battery technology, in addition to improving the performance of battery cells, safety issues have also become a problem that cannot be ignored. If the safety of a battery cell cannot be ensured, the battery cell cannot be used. Therefore, how to improve the safety of battery cells is a technical issue in battery technology that is waiting to be solved as soon as possible. Summary of the Invention

[0004] Aspects of the present application provide electrode assemblies and processing methods and apparatuses, battery cells, batteries and power consuming devices that can improve the safety of battery cells.

[0005] According to a first aspect of the present application, there is provided an electrode assembly, the electrode assembly including: a cathode plate, an anode plate, and a separator, the cathode plate, the separator, and the anode plate being wound along a winding direction to form a folding region, the cathode plate being folded M to form M folding points in the folding region, a first attachment region being formed on an inner surface of the Nth folding point of the cathode plate, and a second attachment region being formed on an outer surface of the Nth folding point, where M and N are positive integers, M≧2, and 1≦N≦M; an ion blocking layer at least a portion of which is attached to the first attachment region, for blocking ions released from the first attachment region from being occluded in the anode plate adjacent to the first attachment region during charging; and a reinforcing layer at least a portion of which is attached to the second attachment region, the reinforcing layer having ion exchange passages provided therein, the ion exchange passages being through holes arranged along a thickness direction of the reinforcing layer.

[0006] The ion-blocking layer is provided on the first attachment region on the inner surface of the N-th folding point of the negative plate in the folding region, thereby effectively reducing the lithium deposition phenomenon. During charging, at least a part of the ions released from the negative active material layer in the first attachment region is blocked by the ion-blocking layer, so that the ions blocked by the ion-blocking layer cannot be absorbed in the positive plate adjacent to the first attachment region, thereby reducing the occurrence of lithium deposition. The reinforcing layer reinforces the negative plate in the second attachment region on the outer surface, and can reduce the occurrence of breakage of the second attachment region of the negative plate or the falling off of the negative active material, thereby improving the safety of the battery cell. In addition, the ion exchange passage on the reinforcing layer allows at least a part of the ions released from the second attachment region to be absorbed in the positive plate adjacent to the second attachment region, so that at least a part of the ions in the second attachment region can complete normal absorption / release and shuttle and exert capacity, thereby improving the safety of the battery cell and improving the capacity of the battery cell.

[0007] In some embodiments, the Nth fold includes a first fold and / or a second fold.

[0008] In this embodiment, the ion blocking layer and the reinforcing layer are provided at the first and / or second folding points of the negative plate in the folding region, which can reduce the occurrence of lithium deposition on the positive plate near the inner surface of the first and / or second folding points of the negative plate, and reduce the occurrence of breakage or detachment of the negative active material layer on the outer surface of the first and / or second folding points of the negative plate, thereby improving the safety of the battery cell and reducing the capacity loss of the battery cell.

[0009] In some embodiments, the electrode assembly has a straight region connected to the folded region, and one end of the ion blocking layer and the reinforcing layer extending along the winding direction is located in the straight region and the other end is located in the folded region, or both ends of the ion blocking layer and the reinforcing layer extending along the winding direction are both located in the straight region. Having one end or both ends of the ion blocking layer and the reinforcing layer located in the straight region can increase the coverage of the ion blocking layer and the reinforcing layer and ensure that the ion blocking layer and the reinforcing layer can be accurately attached to the Nth folded portion of the cathode plate.

[0010] In some embodiments, the ion blocking layer includes a first adhesive layer that is attached to the first attachment region, and the reinforcing layer includes a reinforcing base layer and a second adhesive layer that is attached to the second attachment region via the second adhesive layer.

[0011] In some embodiments, the ion-blocking layer includes a blocking base layer and a first adhesive layer, the blocking base layer being attached to the first attachment region via the first adhesive layer, and the reinforcing layer includes a reinforcing base layer and a second adhesive layer, the reinforcing base layer being attached to the second attachment region via the second adhesive layer.

[0012] In some embodiments, the blocking base layer includes a first body portion and a first extension portion connected to the first body portion, the first adhesive layer for adhering at least a portion of the first body portion to the first attachment area, the first extension portion protruding from the first attachment area in the winding axis direction of the electrode assembly, the reinforcing base layer includes a second body portion and a second extension portion connected to the second body portion, the second adhesive layer for adhering at least a portion of the second body portion to the second attachment area, the second extension portion protruding from the second attachment area in the winding axis direction, the winding axis direction being perpendicular to the winding direction, and the first extension portion and the second extension portion are connected via the first adhesive layer and / or the second adhesive layer.

[0013] In this embodiment, during the process of attaching the ion-blocking layer and the reinforcing layer to the cathode plate, the length of the ion-blocking layer and the reinforcing layer may change due to shearing and tensile stress, which may cause the ion-blocking layer and the reinforcing layer to be unable to completely cover the cathode active material layer on the inner and outer surfaces of the N-th bend of the cathode plate. The first extension protruding from the first attachment area in the winding axis direction is provided on the blocking base layer, and the second extension protruding from the second attachment area in the winding axis direction is provided on the reinforcing base layer, thereby lengthening the length of the ion-blocking layer and the reinforcing layer, and avoiding the risk that the ion-blocking layer and the reinforcing layer may be unable to effectively cover the cathode active material layer on the inner and outer surfaces of the N-th bend of the cathode plate. In addition, since the first adhesive layer and the second adhesive layer have adhesiveness, they may adhere to the winding device during the production process of the electrode assembly, causing defects such as shedding and warping of the ion-blocking layer and the reinforcing layer, and may even cause the ion-blocking layer and the reinforcing layer to break down or destroy the structure of the electrode assembly. By connecting the first extension portion and the second extension portion with the first adhesive layer and / or the second adhesive layer, the portions of the ion-blocking layer and the reinforcing layer protruding from the cathode plate become non-sticky, avoiding the problem of failure caused by adhesion to the winding equipment, and also allowing the ion-blocking layer and the reinforcing layer to adhere to each other, reducing the risk of the ion-blocking layer and the reinforcing layer falling off from the cathode plate, thereby improving the reliability of the ion-blocking layer and the reinforcing layer over the service life of the battery cell.

[0014] In some embodiments, the material of the blocking base layer includes at least one of polyvinyl chloride, polyethylene, polypropylene, polyvinylidene fluoride, hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoropropylene-vinylidene fluoride copolymer, trifluorochloropropylene-vinylidene fluoride copolymer, polyethylene terephthalate, polyimide, polyetherimide, polycarbonate, polystyrene, polyphenylene sulfide, polyvinylidene fluoride or copolymers thereof, polyarylate, fiber, nylon, and nonwoven fabric.

[0015] In some embodiments, the material of the first adhesive layer and / or the second adhesive layer includes at least one of acrylic acid-acrylic acid ester copolymer, butadiene-styrene copolymer, styrene-acrylic acid copolymer, styrene-acrylic acid ester copolymer, ethylene-vinyl acetate copolymer, acrylic acid grafted polyethylene, maleic anhydride grafted polyethylene, acrylic acid grafted polypropylene, maleic anhydride grafted polypropylene, polyvinylidene fluoride, carboxymethyl cellulose, polyimide, polyetherimide, polyethylene terephthalate, styrene-isoprene-styrene copolymer rubber, ethylene-vinyl acetate copolymer bisphenol A type epoxy resin, ethylene-vinyl acetate copolymer bisphenol F type epoxy resin, glyceryl ether type epoxy resin, glyceryl ester type epoxy resin, silicone-based resin, polyurethane, and styrene-isoprene-styrene copolymer.

[0016] In some embodiments, the material of the reinforcing base layer includes at least one of polyvinyl chloride, polyethylene, polypropylene, polyvinylidene fluoride, hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoropropylene-vinylidene fluoride copolymer, trifluorochloropropylene-vinylidene fluoride copolymer, polyethylene terephthalate, polyimide, polyetherimide, polycarbonate, polystyrene, polyphenylene sulfide, polyvinylidene fluoride or copolymers thereof, polyarylate, fiber, nylon, and nonwoven fabric.

[0017] In some embodiments, the through holes extend through the reinforcing base layer and the second adhesive layer.

[0018] In this embodiment, the second adhesive layer can hold the reinforcing layer on the outer surface of the negative plate, the second adhesive layer can further store and hold the electrolyte on the surface of the negative plate and replenish the electrolyte consumed in the cycle process, which is beneficial for ion conduction and diffusion, and further improve the performance of the battery cell, the through-holes can penetrate the reinforcing base layer and the second adhesive layer and provide ion exchange passages through the reinforcing base layer and the second adhesive layer, which is beneficial for the release of the electrolyte and the conduction and diffusion of the ions, which is beneficial for improving the capacity of the battery cell, and improving the cycle performance and service life of the battery cell. The second adhesive layer has a certain fluidity and is prone to movement and deformation on the surface of the negative plate, which will affect the uniformity of the distribution of the electrolyte. The reinforcing base layer allows ions to flow and inhibits the movement and deformation of the second adhesive layer, so that the second adhesive layer can be uniformly maintained on the surface of the negative plate, and the electrolyte can be stably maintained on the surface of the negative plate for a long period of time, which is beneficial to improving the cycle performance and service life of the battery cell.

[0019] In some embodiments, suction regions and punched regions are arranged in the reinforcing layer along the winding direction, and at least a portion of the through holes are distributed in the punched regions, and the porosity of the suction regions is smaller than the porosity of the punched regions, or the through holes are distributed in the reinforcing layer in the form of a zigzag or curved line along the winding axis direction of the electrode assembly.

[0020] In this embodiment, the reinforcing layer is arranged with an adsorption region and a punched region, at least a part of the through-holes are distributed in the punched region, the punched region is for ion passage, which is favorable for the release of electrolyte and the conduction and diffusion of ions, which is favorable for improving the capacity of the battery cell, and for improving the cycle performance and service life of the battery cell. The porosity of the adsorption region is smaller than that of the punched region, which is favorable for using a vacuum adsorption device to adsorb the reinforcing layer onto the negative electrode plate during the production of the electrode assembly, and the small porosity of the adsorption region can reduce the impact on the vacuum adsorption operation.

[0021] In this embodiment, the through holes are arranged in the reinforcing layer in a bent or curved line, so that the through holes are distributed at different widths and heights of the reinforcing layer, and the reinforcing layer can realize the release of electrolyte and the conduction and diffusion of ions at different heights and widths, which is advantageous for improving the cycle performance and service life of the battery. In addition, the bent or curved line makes the porosity of the middle region of the reinforcing layer along the winding direction larger than the porosity of both sides, which is advantageous for forming adsorption regions on both sides of the reinforcing layer.

[0022] According to a second aspect of the present application, there is provided a battery cell, the battery cell including a housing, an electrolyte, a cover plate, and at least one of the electrode assemblies according to the above embodiments, wherein the housing has a receiving cavity and an opening, the electrode assembly and the electrolyte are received in the receiving cavity, and the cover plate is for closing the opening of the housing.

[0023] According to a third aspect of the present application, there is provided a battery, the battery including a housing and at least one battery cell according to the above embodiments, the battery cell being housed within the housing.

[0024] According to a fourth aspect of the present application, there is provided a power consuming device, the power consuming device being configured to receive power provided by the battery of any of the above embodiments.

[0025] According to a fifth aspect of the present application, there is provided a method for processing an electrode assembly, the method including providing a cathode plate, an anode plate, and a separator, the separator being for isolating the cathode plate from the anode plate; the cathode plate, the separator, and the anode plate are wound along a winding direction to form a folding region; the cathode plate is folded M times to form M folding points in the folding region; a first attachment region is formed on an inner surface of the Nth folding point of the cathode plate, and a second attachment region is formed on an outer surface of the Nth folding point; wherein M and N are positive integers, M≧2, and 1≦N≦M; providing an ion-blocking layer and a reinforcing layer; attaching at least a portion of the ion-blocking layer to a first attachment region, wherein the ion-blocking layer prevents ions released from the first attachment region from being absorbed in an anode plate adjacent to the first attachment region during charging; attaching at least a portion of the reinforcing layer to a second attachment region, and providing an ion exchange passage in the reinforcing layer, the ion exchange passage being a through hole arranged along the thickness direction of the reinforcing layer.

[0026] According to a sixth aspect of the present application, there is provided an electrode assembly processing apparatus, the apparatus comprising: a first providing apparatus for providing a cathode plate, an anode plate and a separator, the separator being for isolating the cathode plate from the anode plate; the cathode plate, the separator and the anode plate being wound along a winding direction to form a folding region; the cathode plate being folded M times to form M folding points in the folding region; a first attachment region being formed on an inner surface of the Nth folding point of the cathode plate; and a second attachment region being formed on an outer surface of the Nth folding point, where M and N are positive integers, M≧2. and 1≦N≦M; a second providing device for providing an ion-blocking layer and a reinforcing layer; and an assembly device for attaching at least a portion of the ion-blocking layer to the first attachment region, where the ion-blocking layer prevents ions released from the first attachment region from being occluded in the anode plate adjacent to the first attachment region during charging, and for attaching at least a portion of the reinforcing layer to the second attachment region, where ion exchange passages are provided in the reinforcing layer, the ion exchange passages being through holes arranged along the thickness direction of the reinforcing layer.

[0027] The above description is merely an outline of the technical solutions of the embodiments of the present application, which can be implemented based on the contents of the specification in order to more clearly understand the technical means of the embodiments of the present application, and in order to make the above and other objectives, features and advantages of the embodiments of the present application more obvious and understandable, the following lists specific embodiments of the present application. [Brief description of the drawings]

[0028] In order to more clearly describe the technical solutions of the embodiments of the present application, the following will briefly describe the drawings necessary for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings based on these drawings without creative labor. [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Diagram 2]FIG. 1 is an exploded schematic diagram of a battery according to some embodiments of the present application. [Diagram 3] FIG. 3 is a structural schematic diagram of the battery module shown in FIG. 2. [Figure 4] FIG. 2 is an exploded schematic diagram of a battery cell according to some embodiments of the present application. [Diagram 5] FIG. 1 is a perspective structural schematic diagram of an electrode assembly according to some embodiments of the present application. [Figure 6] 6 is a structural schematic diagram of a cross section along a direction perpendicular to the winding axis K in the electrode assembly of the embodiment shown in FIG. 5. FIG. [Figure 7] FIG. 2 is a structural schematic diagram of an anode plate of an electrode assembly in some embodiments of the present application. [Figure 8] FIG. 2 is a structural schematic diagram of a cathode plate of an electrode assembly in some embodiments of the present application. [Figure 9] FIG. 2 is a structural schematic diagram of a cross section perpendicular to the winding axis in a flat-shaped electrode assembly according to an embodiment of the present application. [Figure 10] FIG. 2 is a structural schematic diagram of a cross section perpendicular to the winding axis of a flat-shaped electrode assembly according to another embodiment of the present application. [Figure 11] FIG. 2 is a structural schematic diagram of a cross section perpendicular to the winding axis of a flat-shaped electrode assembly according to another embodiment of the present application. [Figure 12] FIG. 2 is a structural schematic diagram of the inner surface of the cathode plate of the electrode assembly of some embodiments of the present application after it is unrolled along the winding direction. [Figure 13] FIG. 2 is a structural schematic diagram of the outer surface of the cathode plate of the electrode assembly of some embodiments of the present application after it is unrolled along the winding direction. [Figure 14] FIG. 11 is a structural schematic diagram of the electrode assembly of another embodiment of the present application after the outer surface of the cathode plate is unrolled along the winding direction. [Figure 15] FIG. 14 is a DD cross-sectional structural schematic diagram of one embodiment of the cathode plate of the electrode assembly of FIG. 13 of the present application. [Figure 16] FIG. 14 is a DD cross-sectional structural schematic diagram of another embodiment of the cathode plate of the electrode assembly of FIG. 13 of the present application. [Figure 17] FIG. 14 is a DD cross-sectional structural schematic diagram of another embodiment of the cathode plate of the electrode assembly of FIG. 13 of the present application. [Figure 18] FIG. 14 is a DD cross-sectional structural schematic diagram of another embodiment of the cathode plate of the electrode assembly of FIG. 13 of the present application. [Figure 19] 4 is a flow chart of a method for fabricating an electrode assembly according to another embodiment of the present application. [Figure 20] FIG. 2 is a structural schematic diagram of an electrode assembly processing apparatus according to another embodiment of the present application; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings of the embodiments of the present application. It is clear that the described embodiments are only some of the embodiments of the present application, and are not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the present application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. The terms used in the specification of the application herein are only intended to describe specific embodiments and are not intended to limit the application. The terms "including", "having" and any variations thereof in the specification, claims and above description of the drawings of the application are intended to cover non-exclusive "including".

[0031] When referring to an "embodiment" in the present specification, it means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The phrases appearing in various places in the specification do not necessarily all refer to the same embodiment, nor are they mutually exclusive independent or alternative embodiments. Those skilled in the art can explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0032] The term "and / or" in this text is merely a relational relationship that describes related objects, and indicates that three relations may exist, for example, A and / or B may represent three cases: A alone, A and B in combination, and B alone. Also, the character " / " in this text generally indicates that the related objects before and after are in an "or" relationship.

[0033] In the description of this application, it should be understood that the orientations or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are orientations or positional relationships shown in the drawings, and are merely for the convenience and simplification of the description of this application, and do not indicate or suggest that the indicated device or element has a specific orientation, must be configured and operated in a specific orientation, and therefore should not be understood as a limitation on this application. In addition, terms such as "first", "second" and the like in the specification and claims of this application or the above drawings are used to distinguish different objects, are not intended to describe a specific order, and may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0034] In the description of the present application, it should be explained that unless otherwise clearly specified and limited, the terms "attached", "connected" and "connected" should be understood in a broad sense, for example, may be a fixed connection, a detachable connection, or an integral connection, may be a mechanical connection, may be an electrical connection, may be a direct connection, may be an indirect connection via an intermediate medium, or may communicate the insides of two elements. Those skilled in the art can understand the specific meaning of the above terms in the present application according to the specific situation.

[0035] In the present application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, etc., but is not limited thereto in the embodiments of the present application. The battery cell may have a cylindrical body, a flat body, a rectangular body, or other shapes, etc., but is not limited thereto in the embodiments of the present application. According to the packaging form, the battery cell is generally divided into three types, namely, a prismatic battery cell, a rectangular battery cell, and a pouch battery cell, but is not limited thereto in the embodiments of the present application.

[0036] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or a battery pack. The battery generally includes a housing for packaging one or more battery cells. The housing can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells.

[0037] The battery cell includes an electrode assembly and an electrolyte, and the electrode assembly includes a cathode plate, an anode plate, and a separator. The battery cell is operated mainly by the movement of metal ions between the cathode plate and the anode plate. The cathode plate includes a cathode current collector and a cathode active material layer, and the cathode active material layer is applied to the surface of the cathode current collector. The cathode current collector includes a cathode current collector and a cathode protrusion protruding from the cathode current collector. The cathode active material layer is applied to the cathode current collector, and at least a part of the cathode protrusion is not coated with the cathode active material layer, and the cathode protrusion is a cathode tab. Taking a lithium ion battery as an example, the material of the cathode current collector may be aluminum, the cathode active material layer includes a cathode active material, and the cathode active material may be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganate, etc. The anode plate includes an anode current collector and an anode active material layer, the anode active material layer being applied to the surface of the anode current collector, the anode current collector including an anode current collector and an anode protrusion protruding from the anode current collector, the anode active material layer being applied to the anode current collector, at least a portion of the anode protrusion not being coated with the anode active material layer, and the anode protrusion being an anode tab. The material of the anode current collector may be copper, the anode active material layer including an anode active material, and the anode active material may be carbon or silicon, etc. The number of cathode tabs is stacked in a plurality, and the number of anode tabs is stacked in a plurality, so that melting does not occur even when a large current is passed through it. The material of the separator may be PP (polypropylene) or PE (polyethylene), etc. The electrode assembly may be a wound structure or a stacked structure, and the embodiment of the present application is not limited thereto.

[0038] When a lithium-ion battery is charged, lithium ions are released from the negative active material layer and absorbed into the positive active material layer. However, some abnormal situations may occur, such as insufficient lithium absorption space in the positive active material layer, too large lithium ion absorption resistance in the positive active material layer, or too fast release of lithium ions from the negative active material layer, so that the released lithium ions cannot be absorbed into the positive active material layer of the positive plate in equal amounts, and the lithium ions that cannot be absorbed into the positive plate can only obtain electrons on the surface of the positive plate, forming metallic lithium elements, which is the lithium deposition phenomenon. Lithium deposition not only reduces the performance of the lithium-ion battery and greatly shortens the cycle life, but also limits the fast charging capacity of the lithium-ion battery cell. In addition, when lithium deposition occurs in a lithium-ion battery cell, the activity of the deposited lithium metal is very high and can react with the electrolyte at a low temperature, causing a decrease in the self-heating start temperature of the battery cell and an increase in the self-heating speed, which seriously impairs the safety of the battery cell. Furthermore, when the lithium deposition is severe, the released lithium ions can form lithium crystals on the surface of the positive plate, which are prone to break through the separator, causing the adjacent negative and positive plates to have a risk of short circuit.

[0039] In the research and development process, the inventors found that the lithium deposition phenomenon is likely to occur in the folding area of ​​the wound electrode assembly, and through further research, the inventors found that the lithium deposition phenomenon is mainly caused by the need to fold the cathode plate and anode plate located in the folding area, and the anode plate located inside the cathode plate is likely to have insufficient lithium absorption space, which may cause the lithium absorption sites of the anode active material layer of the anode plate to be less than the number of lithium ions that the cathode active material layer of the adjacent cathode plate can provide, which causes the lithium deposition phenomenon. In addition, the large tensile force that the cathode plate receives on the outer surface of the cathode plate in the folding area may cause the cathode active material layer to break and powder off, which affects the capacity of the battery, and may even expose the current collector of the cathode plate, causing a short circuit, or cause breakage at the folding point of the current collector, which affects safety.

[0040] In view of this, the embodiment of the present application provides a technical solution, in which the electrode assembly is a cathode plate, an anode plate and a separator, the separator is for isolating the anode plate from the cathode plate, the cathode plate, the separator and the anode plate are wound along a winding direction to form a folding region, the cathode plate is folded M times to form M folding points in the folding region, a first attachment region is formed on the inner surface of the Nth folding point of the cathode plate, and a second attachment region is formed on the outer surface of the Nth folding point. The battery cell includes a negative electrode plate, a positive electrode plate, and a separator, where M and N are positive integers, M≧2, and 1≦N≦M, an ion blocking layer, at least a portion of which is attached to the first attachment region, for blocking ions released from the first attachment region during charging from being occluded in the positive electrode plate adjacent to the first attachment region, and a reinforcing layer, at least a portion of which is attached to the second attachment region, the reinforcing layer having ion exchange passages, the ion exchange passages being through holes arranged along the thickness direction of the reinforcing layer. An electrode cell having such a structure can reduce lithium deposition, reduce the risk of the negative electrode active material layer falling off the negative electrode plate and the risk of the negative electrode plate breaking, and improve the capacity and safety of the battery cell.

[0041] The technical solutions described in the embodiments of the present application are applicable to batteries and power-consuming devices using batteries.

[0042] The power consuming device may be a vehicle, a mobile phone, a portable device, a notebook computer, a steamship, a spacecraft, an electric toy, an electric tool, etc. The vehicle may be a fuel oil vehicle, a gas vehicle, or a new energy vehicle, the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or a range extender vehicle, etc., the spacecraft may include an airplane, a rocket, a space shuttle, a spaceship, etc., the electric toy may include a stationary or mobile electric toy, such as a game console, an electric car toy, an electric steamship toy, an electric airplane toy, etc., and the electric tool may include a metal cutting electric tool, a polishing electric tool, an assembly electric tool, and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, a hammer drill, a concrete vibrator, an electric planer, etc. In the embodiment of the present application, the above-mentioned power consuming device is not particularly limited.

[0043] In the following embodiments, for ease of explanation, a case will be described in which the power consuming device is a vehicle.

[0044] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. As shown in FIG. 1, a battery 2 is installed inside the vehicle 1, and the battery 2 may be installed at the bottom, front, or rear of the vehicle 1. The battery 2 can be used to power the vehicle 1, for example, the battery 2 can be an operating power source for the vehicle 1.

[0045] The vehicle 1 may further include a controller 3 and a motor 4, the controller 3 for controlling the battery 2 to power the motor 4 for use in, for example, starting, navigation and operating power needs of the vehicle 1.

[0046] In some embodiments of the present application, the battery 2 can be used not only as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, providing driving power to the vehicle 1 in place of, or in place of, fuel oil or natural gas.

[0047] 2 is an exploded schematic diagram of a battery according to some embodiments of the present application. As shown in FIG. 2, the battery 2 includes a housing 5 and a battery cell (not shown in FIG. 2) housed within the housing 5.

[0048] The housing 5 is for housing the battery cells, and the housing 5 may have various structures. In some embodiments, the housing 5 may include a first housing portion 51 and a second housing portion 52, and the first housing portion 51 and the second housing portion 52 are covered with each other, and the first housing portion 51 and the second housing portion 52 jointly define a housing space 53 for housing the battery cells. The second housing portion 52 may have a hollow structure that opens at one end, and the first housing portion 51 has a plate-like structure, and the first housing portion 51 is covered with the opening side of the second housing portion 52 to form a housing 5 having the housing space 53. The first housing portion 51 and the second housing portion 52 may also have a hollow structure that opens at one side, and the opening side of the first housing portion 51 is covered with the opening side of the second housing portion 52 to form a housing 5 having the housing space 53. Of course, the first housing portion 51 and the second housing portion 52 may have various shapes, for example, a cylindrical body, a rectangular parallelepiped, or the like.

[0049] In order to improve the sealing performance after the first housing part 51 and the second housing part 52 are connected, a sealing member, such as a sealant or a seal ring, may be installed between the first housing part 51 and the second housing part 52.

[0050] Assuming that the first housing part 51 is covered on top of the second housing part 52, the first housing part 51 may be referred to as an upper housing cover, and the second housing part 52 may be referred to as a lower housing.

[0051] The battery 2 may have one or more battery cells. If there are multiple battery cells, the multiple battery cells may be connected in series, parallel, or series-parallel, and series-parallel connection means that the multiple battery cells are connected in both series and parallel. The multiple battery cells may be directly connected in series, parallel, or series-parallel, and then the entire configuration of the multiple battery cells may be housed in the housing 5. Of course, the multiple battery cells may first be connected in series, parallel, or series-parallel to form a battery module 6, and the multiple battery modules 6 may then be connected in series, parallel, or series-parallel to form a whole and housed in the housing 5.

[0052] Fig. 3 is a structural schematic diagram of the battery module shown in Fig. 2. As shown in Fig. 3, in some embodiments, there are a plurality of battery cells 7, and the plurality of battery cells 7 are first connected in series, parallel, or series-parallel to form a battery module 6. The plurality of battery modules 6 are further connected in series, parallel, or series-parallel to form a whole, and are housed in a housing.

[0053] Electrical connection can be realized between the multiple battery cells 7 in the battery module 6 via bus bar members, thereby realizing parallel connection, series connection, or series-parallel connection of the multiple battery cells 7 in the battery module 6.

[0054] 4 is an exploded schematic diagram of a battery cell according to some embodiments of the present application. As shown in FIG. 4, a battery cell 7 according to an embodiment of the present application includes an electrode assembly 10 and an outer casing 20, and the electrode assembly 10 is housed in the outer casing 20.

[0055] In some embodiments, the housing 20 may further be for containing an electrolyte, e.g., an electrolyte solution. The housing 20 may be of various constructions.

[0056] In some embodiments, the outer casing 20 may include a housing 21 and an end cap 22, where the housing 21 is a hollow structure that is open on one side, and the end cap 22 is fitted over the opening of the housing 21 to form a sealed connection and form a sealed space for containing the electrode assembly 10 and the electrolyte.

[0057] The housing 21 may have various shapes, for example, a cylinder, a rectangle, etc. The shape of the housing 21 can be determined based on the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 has a cylindrical structure, a cylindrical housing can be selected. If the electrode assembly 10 has a rectangular parallelepiped structure, a rectangular parallelepiped housing can be selected. Of course, the end cap 22 may have various structures, for example, the end cap 22 is a plate-like structure, a hollow structure with an opening at one end, etc. Exemplarily, in FIG. 4, the housing 21 has a rectangular parallelepiped structure, the end cap 22 has a plate-like structure, and the end cap 22 is covered by the opening at the top of the housing 21.

[0058] In some embodiments, the battery cell 7 may further include a negative electrode terminal 30, a positive electrode terminal 40, and a pressure relief mechanism 50, where the negative electrode terminal 30, the positive electrode terminal 40, and the pressure relief mechanism 50 are all attached to the end cap 22. The negative electrode terminal 30 and the positive electrode terminal 40 are all electrically connected to the electrode assembly 10 for outputting the electric energy generated by the electrode assembly 10. The pressure relief mechanism 50 is for releasing the pressure inside the battery cell 7 when the internal pressure or temperature of the battery cell 7 reaches a preset value.

[0059] Exemplarily, the pressure relief mechanism 50 is located between the negative electrode terminal 30 and the positive electrode terminal 40, and the pressure relief mechanism 50 may be a component such as an explosion-proof valve, an explosion-proof piece, an air valve, a pressure relief valve, or a safety valve.

[0060] Of course, in some other embodiments, the outer casing 20 may have other structures, for example, the outer casing 20 includes a housing 21 and two end caps 22, the housing 21 is a hollow structure with openings on both sides opposite to each other, and one end cap 22 corresponds to and covers one opening of the housing 21 to form a sealed connection, forming a sealed space for containing the electrode assembly 10 and the electrolyte. In such a structure, the cathode electrode terminal 30 and the anode electrode terminal 40 may be attached to the same end cap 22 or different end caps 22. The pressure relief mechanism 50 may be attached to one end cap 22, or the pressure relief mechanism 50 may be attached to both end caps 22.

[0061] It should be noted that the number of electrode assemblies 10 housed in the outer casing 20 of the battery cell 7 may be one or more. For example, there are two electrode assemblies 10 in FIG.

[0062] 5 is a structural schematic diagram of an electrode assembly according to some embodiments of the present application. FIG. 6 is a structural schematic diagram of a cross section along a direction perpendicular to the winding axis K in the electrode assembly of the embodiment shown in FIG.

[0063] As shown in FIGS. 5 and 6, an electrode assembly 10 in an embodiment of the present application includes a cathode plate 11 and an anode plate 12, and the cathode plate 11 and the anode plate 12 are wound along a winding direction A to form a winding structure.

[0064] In the embodiment of the present application, the winding direction A is the direction in which the cathode plate 11 and the anode plate 12 are wound circumferentially from the inside to the outside. In FIG. 5, the winding direction A is the clockwise direction.

[0065] In some embodiments, the electrode assembly 10 further includes a separator 13, which is for isolating the negative electrode plate 11 and the positive electrode plate 12 to reduce the risk of short circuit between the negative electrode plate 11 and the positive electrode plate 12. The separator 13 has a large number of through micropores, which can ensure the free passage of electrolyte and ions, and has excellent permeability to lithium ions, so that the separator 13 can hardly block the passage of lithium ions. For example, the material of the separator 13 may be PP (polypropylene) or PE (polyethylene), etc.

[0066] The cathode plate 11, the anode plate 12 and the separator 13 are all strip-shaped. In the embodiment of the present application, the cathode plate 11, the separator 13 and the anode plate 12 are first stacked in order, and then wound up for two or more turns to form the electrode assembly 10.

[0067] The electrode assembly 10 may have a variety of shapes, for example, the electrode assembly 10 may be a cylindrical body, a flat body, a prismatic body (eg, a triangular, square or hexagonal prism), or other shapes.

[0068] In some embodiments, the winding structure includes a folding region B, which includes a first folding region B1 and a second folding region B2. Both the cathode plate 11 and the anode plate 12 are located at a plurality of folding points in the folding region B. The folding region B is a region having a folding structure in the electrode assembly 10, and both the portion of the cathode plate 11 located at the folding region B (i.e., the folding point of the cathode plate 11) and the portion of the anode plate 12 located at the folding region B (i.e., the folding point of the anode plate 12) are folded and installed. Exemplarily, the folding points of the cathode plate 11 and the folding points of the anode plate 12 are folded in an approximately arc shape. Exemplarily, in the folding region B, the folding points of the cathode plate 11 and the folding points of the anode plate 12 are arranged alternately, i.e., in the folding region B, they are arranged in sequence according to the order of one folding point of the anode plate 12, one folding point of the cathode plate 11, one folding point of the anode plate 12, . . . Optionally, the innermost folding point of the cathode plate 11 is located outside the innermost folding point of the anode plate 12.

[0069] In some embodiments, the electrode assembly 10 is a flat body. Illustratively, the winding structure further includes a straight region C connected to the folding region B. Both the cathode plate 11 and the anode plate 12 include a plurality of straight portions located in the straight region C. The straight region C is a structure having a straight structure in the electrode assembly 10, and optionally, the folding region B is two, and is connected to both ends of the straight region C, respectively.

[0070] The portion of the cathode plate 11 located in the straight region C (i.e., the straight portion of the cathode plate 11) and the portion of the anode plate 12 located in the straight region C (i.e., the straight portion of the anode plate 12) are disposed substantially straight. The surfaces of the straight portion of the cathode plate 11 and the straight portion of the anode plate 12 are both substantially flat.

[0071] As shown in FIG. 6, the first folding region B1 has a midline Z1, and the second folding region B2 has a midline Z2, where the midlines Z1 and Z2 are parallel to the winding axis K of the electrode assembly and extend along the longitudinal direction of the electrode assembly, and the midlines Z1 and Z2 divide the first folding region B1 and the second folding region B2 into two parts, respectively, along the width direction of the electrode assembly.

[0072] The separator 13 has electrical insulation properties and is for isolating the adjacent cathode plate 11 and anode plate 12, thereby preventing short-circuiting between the adjacent cathode plate 11 and anode plate 12. The separator 13 has a large number of through micropores, which can ensure the free passage of electrolyte and ions, and has excellent permeability to lithium ions, so that the separator 13 can hardly block the passage of lithium ions. For example, the separator 13 includes a separator base layer and a functional layer located on the surface of the separator base layer, and the separator base layer includes at least one of polypropylene, polyethylene, ethylene-propylene copolymer, polybutylene terephthalate, etc., and the functional layer may be a mixture layer of ceramic oxide and adhesive.

[0073] The structure of the anode plate 12 may be as shown in FIG. 7, which is a structural schematic diagram of an anode plate in another embodiment of the present application, where the anode plate 12 includes an anode body portion 120 and an anode tab 1203 extending outward from the anode body portion 120 along the winding axis K, and at least a portion of an area along the winding axis K on the surface of the anode body portion 120 is an anode active material layer 1201, which is for applying an anode active material, and the anode active material may be graphite or silicon.

[0074] In another embodiment of the present application, not only is a positive electrode active material layer 1201 provided on a portion of the surface of the positive electrode body 120, but the positive electrode active material layer 1201 is also provided on the surface of the positive electrode tab 1203 and in the root region close to the positive electrode body 120, i.e., a portion of the positive electrode tab 1203 is the positive electrode active material layer 1201.

[0075] In another embodiment of the present application, the positive electrode active material layer 1201 covers the entire surface of the positive electrode body 120 along the winding axis K, as shown in FIG.

[0076] FIG. 8 is a structural schematic diagram of a cathode plate in one embodiment of the present application.

[0077] The negative electrode plate 11 includes a negative electrode body portion 110 and at least one negative electrode tab 1103 extending outward from the negative electrode body portion 110 along the winding axis K, and at least a portion of the surface area of ​​the negative electrode body portion 110 is a negative electrode active material layer 1101, and a negative electrode active material can be applied to the negative electrode active material layer 1101, for example, the negative electrode active material can be a ternary material, lithium manganate or lithium iron phosphate.

[0078] In another embodiment of the present application, the surface of the negative electrode body 110 further includes a first insulating layer-coated area 1102 adjacent to the negative electrode active material layer 1101, the first insulating layer-coated area 1102 is located on the side of the negative electrode active material layer 1101 adjacent to the negative electrode tab 1103, and the first insulating layer-coated area 1102 is for coating an insulating material and for insulating and isolating the negative electrode active material layer 1101 and the negative electrode tab 1103. The two surfaces of the current collector of the negative electrode plate 11 include the negative electrode active material layer 1101, and the negative electrode tab 1103 is a part of the current collector of the negative electrode plate 11, where the material of the current collector may be aluminum.

[0079] For example, the negative electrode active material layer 1101 and the first insulating layer coated area 1102 are distributed on both ends along the winding axis K on the surface of the negative electrode body 110, and the negative electrode tab 1103 and the first insulating layer coated area 1102 belong to the same end of the negative electrode body 110.

[0080] In another embodiment of the present application, the negative electrode active material layer 1101 and the first insulating layer coated area 1102 are two approximately parallel regions on the surface of the negative electrode body portion 110, and are distributed in two layers on the surface of the negative electrode body portion 110 along the winding axis K.

[0081] In another embodiment of the present application, the first insulating layer application area 1102 may be located at a portion where the cathode body portion 110 and the cathode tab 1103 are connected to each other, for example, the first insulating layer application area 1102 is located on the surface of the cathode body portion 110 and at a portion where the cathode tab 1103 is connected to each other, and is for separating the surface of the cathode tab 1103 from the cathode active material layer 1101. In another embodiment of the present application, not only is the first insulating layer application area 1102 provided on the surface of the cathode body portion 110, but a second insulating layer application area is also provided in a root region of the cathode tab 1103 close to the cathode body portion 110, and the second insulating layer application area is for applying an insulating material.

[0082] In another embodiment of the present application, an insulating material is applied to the surface of the first insulating layer application area 1102, and the insulating material includes an inorganic filler and an adhesive. The inorganic filler includes one or more of boehmite, alumina, magnesium oxide, titanium dioxide, zirconium oxide, silicon dioxide, silicon carbide, boron carbide, calcium carbonate, aluminum silicate, calcium silicate, potassium titanate, and barium sulfate. The adhesive includes one or more of polyvinylidene fluoride, polyacrylonitrile, polyacrylic acid, polyacrylic acid ester, polyacrylic acid-acrylic acid ester, polyacrylonitrile-acrylic acid, and polyacrylonitrile-acrylic acid ester.

[0083] In another embodiment of the present application, each cathode plate 11 may include one or more cathode tabs 1103, and when the cathode plate 11 includes more than one cathode tab 1103, all of the cathode tabs 1103 are located on the same side of the cathode plate 11 along the winding axis K.

[0084] When the negative electrode plate 11 and the positive electrode plate 12 are stacked together, both ends of the positive electrode active material layer 1201 of the positive electrode plate 12 along the winding axis K exceed the corresponding ends of the negative electrode active material layer 1101 of the adjacent negative electrode plate 11, so that the electrode assembly can have good energy density. For example, the both ends of the positive electrode active material layer 1201 along the winding axis K are the first end 1204 and the second end 1205, respectively, and the both ends of the negative electrode active material layer 1101 along the winding axis K are the third end 1104 and the fourth end 1105, respectively, where the first end 1204 of the positive electrode active material layer 1201 and the third end 1104 of the negative electrode active material layer 1101 are located on the same side of the electrode assembly along the winding axis K; Furthermore, the first end 1204 of the positive electrode active material layer 1201 extends beyond the third end 1104 of the negative electrode active material layer 1101 along the winding axis K, and the second end 1205 of the positive electrode active material layer 1201 and the fourth end 1105 of the negative electrode active material layer 1101 are located on the other side of the electrode assembly 10 along the winding axis K, and the second end 1205 of the positive electrode active material layer 1201 extends beyond the fourth end 1105 of the negative electrode active material layer 1101 along the winding axis K.

[0085] The extent to which both ends of positive electrode active material layer 1201 along winding axis K extend beyond the corresponding ends of negative electrode active material layer 1101 may be the same or different, and the extent may range from 0.2 mm to 5 mm, for example.

[0086] FIG. 9 is a structural schematic diagram of a cross section perpendicular to the winding axis in a flat-shaped electrode assembly according to one embodiment of the present application.

[0087] The electrode assembly 10 in this embodiment comprises a cathode plate 11, an anode plate 12 and a separator 13. The separator 13 is for isolating the cathode plate 11 and the anode plate 12, and the cathode plate 11, the separator 13, and the anode plate 12 are wound along a winding direction A to form a folding region B, the cathode plate 11 is folded M to form M folding points in the folding region, a first attachment region is formed on an inner surface 11U of the Nth folding point of the cathode plate 11, and a second attachment region is formed on an outer surface 11V of the Nth folding point, where M and N are positive integers, M≧2, and 1≦N≦M. The battery includes the cathode plate 11, the anode plate 12, and the separator 13, at least a portion of which is attached to the first attachment region and which prevents ions released from the first attachment region from being occluded by the anode plate 12 adjacent to the first attachment region during charging, and a reinforcing layer 9 at least a portion of which is attached to the second attachment region, and in which an ion exchange passage is provided in the reinforcing layer 9.

[0088] In some embodiments, the ion exchange channels are through holes 90 located along the thickness of the reinforcing layer 9 .

[0089] In some embodiments, a cathode active material layer 1101 is provided on each of the inner surface 11U and the outer surface 11V of the cathode plate 11, a first attachment region is formed in the cathode active material layer 1101 on the inner surface 11U of the Nth folding portion of the cathode plate 11, and a second attachment region is formed in the cathode active material layer 1101 on the outer surface 11V of the Nth folding portion, and during charging, the ion blocking layer 8 is for preventing ions released from the first attachment region from being absorbed in the anode plate 12 adjacent to the first attachment region, and during charging, the ion exchange passages on the reinforcing layer 9 allow at least a portion of ions released from the second attachment region to be absorbed in the anode plate 12 adjacent to the second attachment region.

[0090] The ion blocking layer 8 is provided in the first attachment region of the inner surface 11U of the N-th folding portion of the negative electrode plate 11 in the folding region B, so that the lithium deposition phenomenon can be effectively reduced. During charging, at least a part of the ions released from the negative electrode active material layer 1101 in the first attachment region is blocked by the ion blocking layer 8, so that the ions blocked by the ion blocking layer 8 cannot be absorbed in the positive electrode plate 12 adjacent to the first attachment region, thereby reducing the occurrence of lithium deposition. The reinforcing layer 9 reinforces the second attachment region of the outer surface 11V of the negative electrode plate 11, and can reduce the occurrence of breakage or detachment of the negative electrode active material in the second attachment region of the negative electrode plate 11, thereby improving the safety of the battery cell 7. In addition, the ion exchange passages of the reinforcing layer 9 allow at least a portion of the ions released from the second adhesion region to be absorbed in the anode plate 12 adjacent to the second adhesion region, so that at least a portion of the ions in the second adhesion region can complete normal absorption / release and shuttle, and fully exert the capacity of the battery cell 7, thereby improving the safety of the battery cell 7 and improving the capacity of the battery cell 7.

[0091] In some embodiments, the inner surface 11U of the cathode plate 11 refers to the surface of the cathode plate 11 facing the winding axis K. The outer surface 11V of the cathode plate refers to the surface of the cathode plate 11 facing away from the winding axis K.

[0092] In some embodiments, the formation of a first attachment region in the cathode active material layer 1101 of the inner surface 11U of the Nth folding position of the cathode plate 11 means that a first attachment region is formed in the cathode active material layer 1101 of one or more inner surfaces 11U of the first folding position to the Mth folding position of the cathode plate 11. The Nth folding position refers to a folding position formed during the Nth folding after the winding structure is folded 1, 2...N along the winding direction A in an unfolded state.

[0093] In some embodiments, applying refers to gluing or painting or spraying.

[0094] The first attachment area refers to the area that the ion blocking layer 8 covers when it is attached to the inner surface 11U of the cathode plate 11. The second attachment area refers to the area that the reinforcing layer 9 covers when it is attached to the outer surface 11V of the cathode plate 11.

[0095] FIG. 9 is a structural schematic diagram of a cross section perpendicular to the winding axis K in a flat-shaped electrode assembly according to one embodiment of the present application, FIG. 10 is a structural schematic diagram of a cross section perpendicular to the winding axis K in another flat-shaped electrode assembly according to another embodiment of the present application, and FIG. 11 is a structural schematic diagram of a cross section perpendicular to the winding axis K in another flat-shaped electrode assembly according to another embodiment of the present application.

[0096] In some embodiments, the Nth fold includes a first fold and / or a second fold.

[0097] In the embodiment shown in FIG. 9 , the Nth folding point includes a first folding point 111 of the cathode plate 11, and a first ion-blocking layer 18 is provided in a first attachment area on an inner surface 11U of the first folding point 111, and a first reinforcing layer 19 is provided in a second attachment area on an outer surface 11V of the first folding point 111.

[0098] In the embodiment shown in FIG. 10 , the Nth folding point includes a first folding point 111 and a second folding point 112 of the cathode plate 11, and a first ion-blocking layer 18 is provided in a first attachment area on the inner surface 11U of the first folding point 111, a first reinforcing layer 19 is provided in a first attachment area on the outer surface 11V of the first folding point 111, a second ion-blocking layer 28 is provided in a first attachment area on the inner surface 11U of the second folding point 112, and a second reinforcing layer 29 is provided in a second attachment area on the outer surface 11V of the second folding point 112.

[0099] The Nth folding point is not limited to the first folding point and the second folding point, but may further include the third, fourth, fifth, and sixth folding points, and in some embodiments, the ion blocking layer 8 and the reinforcing layer 9 may be provided at all of the first to Mth folding points.

[0100] In this embodiment, the ion blocking layer 8 and the reinforcing layer 9 are provided at the first folding point 111 and / or the second folding point 112 of the negative electrode plate 11 in the folding region B, which can reduce the occurrence of lithium deposition on the positive electrode plate 12 near the inner surface 11U of the first folding point 111 and / or the second folding point 112 of the negative electrode plate 11, and can reduce the occurrence of breakage or detachment of the negative electrode active material layer on the outer surface 11V of the first folding point 111 and / or the second folding point 112 of the negative electrode plate 11, thereby improving the safety of the battery cell 7 and reducing the capacity loss of the battery cell 7.

[0101] In some embodiments, the electrode assembly 10 has a straight region C connected to a folding region B, and one end of the ion-blocking layer 8 and the reinforcing layer 9 extending along the winding direction A is located in the straight region C and the other end is located in the folding region B, or both ends of the ion-blocking layer 8 and the reinforcing layer 9 extending along the winding direction A are located in the straight region C. Since there may be an error in the attachment of the ion-blocking layer 8 and the reinforcing layer 9, if the length of the ion-blocking layer 8 and the reinforcing layer 9 is too short, they may not be able to accurately cover the cathode plate 11 in the folding region B. By having one or both ends of the ion-blocking layer 8 and the reinforcing layer 9 located in the straight region C, the coverage of the ion-blocking layer 8 and the reinforcing layer 9 can be increased, and it can be ensured that the ion-blocking layer 8 and the reinforcing layer 9 can be accurately attached to the Nth folding point of the cathode plate 11.

[0102] 11, both ends of the ion-blocking layer 8 and the reinforcing layer 9 extending along the winding direction A are located in the straight region C. This ensures that the ion-blocking layer 8 and the reinforcing layer 9 can be accurately attached to the Nth folding position of the cathode plate 11.

[0103] FIG. 12 is a structural schematic diagram of the inner surface 11U of the cathode plate of the electrode assembly in some embodiments of the present application after it is unrolled along the winding direction.

[0104] In this embodiment, the ion-blocking layer 8 is provided in a first attachment region on the inner surface 11U of the Nth folding portion of the cathode plate 11. In the winding direction A, the ion-blocking layer 8 covers the midline of the folding region B, and as shown in the embodiment of FIG. 11, the first ion-blocking layer 18 covers the midline Z1 of the first folding region B1, and the second ion-blocking layer 28 covers the midline Z2 of the second folding region B2. In the winding direction A, both ends of the ion-blocking layer 8 may be located in the folding region B, or one end of the ion-blocking layer 8 extending along the winding direction A may be located in the straight region C and the other end may be located in the folding region B, or both ends of the ion-blocking layer 8 extending along the winding direction A may be located in the straight region C.

[0105] In this embodiment, in the direction of the winding axis K, one end of the ion-blocking layer 8 is connected to the first insulating layer coating area 1102 beyond the third end 1104 of the negative electrode active material layer 1101, and the other end of the ion-blocking layer 8 extends to at least the fourth end 1105 of the negative electrode active material layer 1101. In this way, it is possible to ensure that the ion-blocking layer 8 covers the entire negative electrode active material layer 1101 in the direction of the winding axis K, and the occurrence of lithium deposition can be effectively avoided. In some embodiments, in the direction of the winding axis K, the second end of the ion-blocking layer 8 may exceed the fourth end 1105 of the negative electrode active material layer 1101. In the process of attaching the ion-blocking layer 8 to the negative electrode plate 11, the length of the ion-blocking layer 8 may change due to shearing and tensile stress, and the ion-blocking layer 8 may not completely cover the negative electrode active material layer 1101 on the inner surface 11U of the Nth folding portion of the negative electrode plate 11. By arranging the ion-blocking layer 8 so that it protrudes from the first attachment region in the direction of the winding axis K, the length of the ion-blocking layer 8 is increased, thereby avoiding the risk that the ion-blocking layer 8 will not be able to effectively cover the cathode active material layer 1101 on the inner surface 11U of the Nth folding point of the cathode plate 11.

[0106] Fig. 13 is a structural schematic diagram of the outer surface of the cathode plate of the electrode assembly of some embodiments of the present application after it is unrolled along the winding direction. Fig. 14 is a structural schematic diagram of the outer surface of the cathode plate of the electrode assembly of another embodiment of the present application after it is unrolled along the winding direction.

[0107] 13, in some embodiments of the present application, a reinforcing layer 9 is installed in the second attachment region of the outer surface 11V of the N-th folding portion of the cathode plate 11. In the winding direction A, the reinforcing layer 9 covers the midline of the folding region B, and as shown in the embodiment of FIG. 11, the first reinforcing layer 19 covers the midline Z1 of the first folding region B1, and the second reinforcing layer 29 covers the midline Z2 of the second folding region B2. In the winding direction A, both ends of the reinforcing layer 9 may be located in the folding region B, or one end of the reinforcing layer 9 extending along the winding direction A is located in the straight region C and the other end is located in the folding region B, or both ends of the reinforcing layer 9 extending along the winding direction A are located in the straight region C.

[0108] In this embodiment, in the direction of the winding axis K, one end of the reinforcing layer 9 is connected to the first insulating layer coating area 1102 beyond the third end 1104 of the negative electrode active material layer 1101, and the other end of the reinforcing layer 9 extends to at least the fourth end 1105 of the negative electrode active material layer 1101. In this way, it is possible to ensure that the reinforcing layer 9 covers the entire negative electrode active material layer 1101 in the direction of the winding axis K, and it is possible to effectively prevent the negative electrode active material on the outer surface 11V from falling off or cracking. In some embodiments, in the direction of the winding axis K, the second end of the reinforcing layer 9 may further exceed the fourth end 1105 of the negative electrode active material layer 1101. In the process of attaching the reinforcing layer 9 to the negative electrode plate 11, the length of the reinforcing layer 9 may change due to shearing and tensile stress, and the reinforcing layer 9 may not completely cover the negative electrode active material layer 1101 on the outer surface 11V of the Nth folding portion of the negative electrode plate 11. By arranging the reinforcing layer 9 so that it protrudes from the first attachment region in the direction of the winding axis K, the length of the reinforcing layer 9 is increased, thereby avoiding the risk that the reinforcing layer 9 will not be able to effectively cover the negative electrode active material layer 1101 on the outer surface 11V of the Nth folding point of the negative electrode plate 11.

[0109] In some embodiments, the reinforcing layer 9 is provided with ion exchange passages, which are through-holes 90 arranged along the thickness direction of the reinforcing layer 9 and allow ions to pass through. The through-holes 90 are for the passage of ions, which is favorable for the release of electrolyte and the conduction and diffusion of ions, which is favorable for improving the capacity of the battery cell 7, and which improves the cycle performance and service life of the battery cell 7.

[0110] In some embodiments, such as the embodiment shown in FIG. 13, suction regions X and punch regions Y are arranged in the reinforcing layer 9 along the winding direction, at least a portion of the through holes 90 are distributed in the punch regions Y, and the porosity of the suction regions X is smaller than the porosity of the punch regions Y.

[0111] In this embodiment, the reinforcing layer 9 is arranged with an adsorption region X and a punched region Y, and at least a part of the through-holes 90 is distributed in the punched region Y, and the punched region Y is for the passage of ions, which is favorable for the release of electrolyte and the conduction and diffusion of ions, and is favorable for improving the capacity of the battery cell, and improving the cycle performance and service life of the battery cell. The porosity X of the adsorption region is smaller than that of the punched region, so that when producing the electrode assembly 10, it is favorable to attach the reinforcing layer 9 to the negative electrode plate 11 by adsorbing it to the adsorption region X using a vacuum adsorption device, and the small porosity of the adsorption region X can reduce the impact on the vacuum adsorption operation. The porosity refers to the ratio of the total volume of all pores connected in the bulk material to the total volume of the bulk material.

[0112] The through holes 90 may be multiple and distributed uniformly or non-uniformly in the punched region Y. For example, the through holes 90 may be arranged in an array in the punched region Y. A small number of holes may be punched in the adsorption region X, which is more favorable for the release of the electrolyte and the conduction and diffusion of ions, and the adsorption region X may not be punched, so that the adsorption region has good adsorption performance. The punched region Y and the adsorption region X are alternately arranged along the winding direction A, and as shown in the embodiment of FIG. 13, two punched regions Y are provided in the reinforcing layer 9, and three adsorption regions X are provided in the middle or on both sides of the two punched regions Y. In some embodiments, the other end of the reinforcing layer 9 exceeds the fourth end 1105 of the negative electrode active material layer 1101, and the punched region Y may or may not be punched in the part beyond the reinforcing layer 9.

[0113] In some other embodiments, such as the embodiment shown in FIG. 14, the through holes 90 are distributed in the reinforcing layer 9 along the direction of the winding axis K of the electrode assembly 10, forming a bent line or a curved line.

[0114] In this embodiment, the through holes 90 are arranged in the reinforcing layer 9 to form a broken line or a curved line, so that the through holes 90 are distributed in both the winding direction A and the winding circumferential direction K of the reinforcing layer 9, and the reinforcing layer 9 can realize the release of electrolyte and the conduction and diffusion of ions in both the different winding directions A and K, which is advantageous for improving the cycle performance and service life of the battery. In addition, the broken line or curved line makes the porosity of the middle region of the reinforcing layer 9 along the winding direction greater than the porosity on both sides, which is advantageous for forming adsorption regions on both sides of the reinforcing layer 9.

[0115] Figure 15 is a schematic diagram of the DD cross-sectional structure of one embodiment of the cathode plate of the electrode assembly of Figure 13 of the present application, Figure 16 is a schematic diagram of the DD cross-sectional structure of another embodiment of the cathode plate of the electrode assembly of Figure 13 of the present application, Figure 17 is a schematic diagram of the DD cross-sectional structure of another embodiment of the cathode plate of the electrode assembly of Figure 13 of the present application, and Figure 18 is a schematic diagram of the DD cross-sectional structure of another embodiment of the cathode plate of the electrode assembly of Figure 13 of the present application.

[0116] Referring to FIG. 15, in some embodiments of the present application, the ion-blocking layer 8 and the reinforcing layer 9 are disposed on the inner surface 11U and the outer surface 11V of the Nth folding portion of the cathode plate 11, respectively.

[0117] As shown in FIG. 16, in some embodiments of the present application, the ion blocking layer 8 includes a first adhesive layer 82 that is attached to a first attachment region, and the reinforcing layer 9 includes a reinforcing base layer 91 and a second adhesive layer 92 that is attached to the second attachment region via the second adhesive layer 92.

[0118] In some embodiments, the material of the first adhesive layer 82 and / or the second adhesive layer 92 may include one or more combinations of acrylic acid-acrylic acid ester copolymer, butadiene-styrene copolymer, styrene-acrylic acid copolymer, styrene-acrylic acid ester copolymer, ethylene-vinyl acetate copolymer, acrylic acid grafted polyethylene, maleic anhydride grafted polyethylene, acrylic acid grafted polypropylene, maleic anhydride grafted polypropylene, polyvinylidene fluoride, carboxymethyl cellulose, polyimide, polyetherimide, polyethylene terephthalate, styrene-isoprene-styrene copolymer rubber, ethylene-vinyl acetate copolymer bisphenol A type epoxy resin, ethylene-vinyl acetate copolymer bisphenol F type epoxy resin, glyceryl ether type epoxy resin, glyceryl ester type epoxy resin, silicone-based resin, polyurethane, and styrene-isoprene-styrene copolymer. The materials of the first adhesive layer and the second adhesive layer may be the same or different. The first adhesive layer 82 and the second adhesive layer 92 may be adhesives.

[0119] In some embodiments, the material of the reinforcing base layer 91 may include one or more combinations of polyvinyl chloride, polyethylene, polypropylene, polyvinylidene fluoride, hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoropropylene-vinylidene fluoride copolymer, trifluorochloropropylene-vinylidene fluoride copolymer, polyethylene terephthalate, polyimide, polyetherimide, polycarbonate, polystyrene, polyphenylene sulfide, polyvinylidene fluoride or its copolymer, polyarylate, fiber, nylon, nonwoven fabric, etc. The reinforcing base layer 91 may be a tape.

[0120] In the embodiment of FIGS. 16 and 17, the reinforcing layer 9 is provided with through holes 90 that allow the passage of ions, and the through holes 90 pass through the reinforcing base layer 91 and the second adhesive layer 92 .

[0121] The second adhesive layer 92 can hold the reinforcing layer on the outer surface of the negative electrode plate 11, the second adhesive layer 92 can further store and hold the electrolyte on the surface of the negative electrode plate 11, and can also replenish the electrolyte consumed in the cycle process, which is beneficial for the conduction and diffusion of ions, and further improve the performance of the battery cell, the through-holes 90 can penetrate the reinforcing base layer 91 and the second adhesive layer 92 and penetrate the reinforcing base layer 91 and the second adhesive layer 92 by ion exchange passages, which is beneficial for the release of electrolyte and the conduction and diffusion of ions, which is beneficial for the capacity improvement of the battery cell 7, and improve the cycle performance and service life of the battery cell 7. The second adhesive layer 92 has a certain fluidity and is prone to movement and deformation on the surface of the negative electrode plate 11, which will affect the uniformity of the distribution of the electrolyte. The reinforcing base layer 91 allows ions to flow and inhibits the flow and deformation of the second adhesive layer 92, so that the second adhesive layer 92 can be uniformly maintained on the surface of the negative electrode plate 11, and the electrolyte can be stably maintained on the surface of the negative electrode plate 11 for a long period of time, which is advantageous for improving the cycle performance and service life of the battery cell 7.

[0122] As shown in FIG. 17, in some other embodiments of the present application, the ion blocking layer 8 includes a blocking base layer 81 and a first adhesive layer 82, where the blocking base layer 81 is attached to the first attachment region via the first adhesive layer 82, and the reinforcing layer 9 includes a reinforcing base layer 91 and a second adhesive layer 92, where the reinforcing base layer 91 is attached to the second attachment region via the second adhesive layer 92.

[0123] In this embodiment, the material of the blocking base layer 81 may include one or more combinations of polyvinyl chloride, polyethylene, polypropylene, polyvinylidene fluoride, hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoropropylene-vinylidene fluoride copolymer, trifluorochloropropylene-vinylidene fluoride copolymer, polyethylene terephthalate, polyimide, polyetherimide, polycarbonate, polystyrene, polyphenylene sulfide, polyvinylidene fluoride or its copolymer, polyarylate, fiber, nylon, and nonwoven fabric. The blocking base layer 81 may be a tape.

[0124] The materials of the first adhesive layer 82, the second adhesive layer 92 and the reinforcing base layer 91 may refer to the above embodiments.

[0125] In some other embodiments, as shown in FIG. 18, the blocking base layer 81 includes a first body portion 81a and a first extension portion 81b connected to the first body portion 81a, the first adhesive layer 82 is for adhering at least a portion of the first body portion 81a to the first attachment region, and the first extension portion 81b protrudes from the first attachment region in the winding axis K direction of the electrode assembly 10, and the reinforcing base layer 91 includes a second body portion 91a and and a second extension portion 91b connected to the second main body portion 91a, the second adhesive layer 92 is for adhering at least a portion of the second main body portion 91a to the second attachment area, the second extension portion 91b protrudes from the second attachment area in the direction of the winding axis K, the direction of the winding axis K being perpendicular to the winding direction A, and the first extension portion 81b and the second extension portion 91b are connected via the first adhesive layer 82 and / or the second adhesive layer 92.

[0126] In this embodiment, in the process of attaching the ion blocking layer 8 and the reinforcing layer 9 to the cathode plate 11, the length of the ion blocking layer 8 and the reinforcing layer 9 may change due to cutting and tensile stress, which may cause the ion blocking layer 8 and the reinforcing layer 9 to be unable to completely cover the cathode active material layer 1101 on the inner surface 11U and the outer surface 11V of the Nth folding portion of the cathode plate 11. The blocking base layer 81 is provided with a first extension 81b protruding from the first attachment region in the direction of the winding axis K, and the reinforcing base layer 91 is provided with a second extension 91b protruding from the second attachment region in the direction of the winding axis K, thereby increasing the length of the ion blocking layer 8 and the reinforcing layer 9, thereby avoiding the risk that the ion blocking layer 8 and the reinforcing layer 9 may be unable to effectively cover the cathode active material layer 1101 on the inner surface 11U and the outer surface 11V of the Nth folding portion of the cathode plate 11. If the ion blocking layer 8 cannot effectively cover the negative electrode active material layer 1101 on the inner surface 11U, there is a risk of lithium deposition. If the reinforcing layer 9 cannot effectively cover the negative electrode active material layer 1101 on the outer surface 11V, the negative electrode plate may break or the negative electrode active material may fall off.

[0127] In addition, since the first adhesive layer 82 and the second adhesive layer 92 have adhesiveness, during the production process of the electrode assembly 10, they may adhere to a winding device, causing defects such as detachment and warping of the ion-blocking layer 8 and the reinforcing layer 9, and may even cause failure of the ion-blocking layer 8 and the reinforcing layer 9 or destroy the structure of the electrode assembly. By connecting the first extension 81b and the second extension 91b with the first adhesive layer 82 and / or the second adhesive layer 92, the adhesiveness of the parts of the ion-blocking layer 8 and the reinforcing layer 9 protruding from the cathode plate 11 is eliminated, avoiding the problem of failure due to adhesion to the winding device, and also reducing the risk of the ion-blocking layer 8 and the reinforcing layer 9 adhering to each other and detaching from the cathode plate 11, thereby improving the reliability of the ion-blocking layer 8 and the reinforcing layer 9 during the service life of the battery cell 7.

[0128] Adhering the first extension portion 81b and the second extension portion 91b with the first adhesive layer 82 and / or the second adhesive layer 92 specifically means that the first adhesive layer 82 may be provided only on the first extension portion 81b or the second adhesive layer 92 may be provided only on the second extension portion 91b, and the first extension portion 81b and the second extension portion 91b are connected with the first adhesive layer 82 or the second adhesive layer 92. Alternatively, the first adhesive layer 82 is provided on the first extension portion 81b, and the second adhesive layer 92 is provided on the second extension portion 91b, and the first extension portion 81b and the second extension portion 91b are connected with the first adhesive layer 82 and the second adhesive layer 92.

[0129] In some other embodiments, the blocking base layer 81 further includes a third extension portion, which is connected to the first main body portion 81a and is located at one end opposite to the first extension portion 81b in the winding axis K direction and protrudes from the first attachment region, and the reinforcing base layer 91 further includes a fourth extension portion, which is connected to the second main body portion 91a and is located at one end opposite to the second extension portion 91b in the winding axis K direction and protrudes from the second attachment region. The first extension portion 81b and the second extension portion 91b are connected to each other at one end in the winding circumferential direction K via the first adhesive layer 82 and / or the second adhesive layer 92. The third extension portion and the fourth extension portion are connected to each other at the other end in the winding circumferential direction K via the first adhesive layer 82 and / or the second adhesive layer 92. This further reduces the risk of the ion-blocking layer 8 and the reinforcing layer 9 falling off from the cathode plate 11, and improves the reliability of the ion-blocking layer 8 and the reinforcing layer 9 over the service life of the battery cell 7.

[0130] FIG. 19 is a flow chart of a method for manufacturing an electrode assembly according to some embodiments of the present application.

[0131] As shown in FIG. 19, the manufacturing method of the electrode assembly according to the embodiment of the present application includes the following steps: S100, providing a positive electrode plate, a negative electrode plate and a separator, the separator being for isolating a negative electrode plate and a positive electrode plate, the negative electrode plate, the separator and the positive electrode plate being wound along a winding direction to form a folding region, the negative electrode plate being folded M times to form M folding points in the folding region, a first attachment region being formed on an inner surface of the Nth folding point of the negative electrode plate, and a second attachment region being formed on an outer surface of the Nth folding point, where M and N are positive integers, M≧2, and 1≦N≦M; S200, providing an ion-blocking layer and a reinforcing layer; S300, at least a portion of an ion-blocking layer is attached to a first attachment region, and during charging, the ion-blocking layer is for preventing ions released from the first attachment region from being absorbed in an anode plate adjacent to the first attachment region; at least a portion of a reinforcing layer is attached to a second attachment region, and an ion exchange passage is provided in the reinforcing layer, the ion exchange passage being a through hole arranged along the thickness direction of the reinforcing layer.

[0132] It should be noted that the structures related to the electrode assembly manufactured by the above-mentioned manufacturing method of the electrode assembly may refer to the electrode assemblies provided by the above-mentioned embodiments.

[0133] When assembling an electrode assembly based on the above-mentioned manufacturing method of an electrode assembly, the steps do not necessarily have to be performed in the order mentioned above, that is, the steps may be performed in the order mentioned in the embodiment, or in an order different from the order mentioned in the embodiment, or multiple steps may be performed simultaneously. For example, step S100 and step S200 may be performed in a random order or simultaneously.

[0134] FIG. 20 is a schematic block diagram of a manufacturing system for an electrode assembly according to some embodiments of the present application.

[0135] As shown in FIG. 20, a manufacturing system 400 for an electrode assembly according to an embodiment of the present application includes: a first providing device 401 for providing a cathode plate, an anode plate and a separator, the separator being for isolating the cathode plate from the anode plate, the cathode plate, the separator and the anode plate being wound along a winding direction to form a folding region, the cathode plate being folded M times to form M folding points in the folding region, a first attachment region being formed on an inner surface of the Nth folding point of the cathode plate, and a second attachment region being formed on an outer surface of the Nth folding point, where M and N are positive integers, M≧2, and 1≦N≦M; a second providing device 402 for providing an ion blocking layer and a backing layer; the assembly device 403 for attaching at least a portion of the ion-blocking layer to the first attachment region, wherein during charging, the ion-blocking layer is configured to prevent ions released from the first attachment region from being absorbed in the anode plate adjacent to the first attachment region; and the assembly device 403 for attaching at least a portion of the reinforcing layer to the second attachment region, wherein an ion exchange passage is provided in the reinforcing layer, the ion exchange passage being a through hole arranged along the thickness direction of the reinforcing layer.

[0136] The structure related to the electrode assembly manufactured by the manufacturing system may refer to the electrode assemblies according to the above embodiments.

[0137] As will be understood by those skilled in the art, some embodiments herein include some features that are included in other embodiments but not other features, and it is meant that a combination of features of different embodiments forms a different embodiment within the scope of the present application. For example, any one of the embodiments that are to be protected in the claims may be used in any combination manner.

[0138] The above embodiments are only used to explain the technical solutions of the present application, and are not intended to limit the same. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art can still understand that the technical solutions described in the above embodiments can be modified or some of the technical features can be replaced with equivalents, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application. [Explanation of symbols]

[0139] 1 vehicle 2 batteries 3. Controller 4 Motor 5. Cabinet 6 Battery Module 7 Battery Cells 8 Ion blocking layer 9 Reinforcement layer 10 Electrode Assembly 11 Cathode plate 12 Anode plate 13 Separator 18 First ion blocking layer 19 First Reinforcement Layer 20 Outer casing 21 Housing 22 End cap 28 Second ion blocking layer 29 Second Reinforcement Layer 30 Cathode electrode terminal 40 Anode electrode terminal 50 Pressure relief mechanism 51 First housing part 52 Second housing part 53 Containment Space 81 Blocking Base Layer 82 First adhesive layer 90 Through hole 91 Reinforced base layer 92 Second adhesive layer 110 Cathode body 120 Anode body 1101 Cathode active material layer 1102 First insulating layer coating area 1103 Cathode tab 1104 The Third Edge 1105 The Fourth Edge 1201 Anode active material layer 1203 Anode tab 1204 First Edge 1205 Second End

Claims

1. An electrode assembly for a lithium ion battery, comprising: A cathode plate, an anode plate, and a separator, the cathode plate, the separator, and the anode plate being wound along a winding direction to form a folding region; the cathode plate is folded M times to form M folding points in the folding region; a negative electrode plate, a positive electrode plate, and a separator, wherein a first attachment area is formed on an inner surface of an Nth folding portion of the negative electrode plate, and a second attachment area is formed on an outer surface of the Nth folding portion, where M and N are positive integers, M≧2, and 1≦N≦M; an ion blocking layer, at least a portion of which is attached to the first attachment region, for preventing ions released from the first attachment region from being absorbed by the anode plate adjacent to the first attachment region during charging; a reinforcing layer at least a portion of which is attached to the second attachment region, the reinforcing layer being provided with an ion exchange passage, the ion exchange passage being a through hole provided along a thickness direction of the reinforcing layer; the ion blocking layer includes a blocking base layer and a first adhesion layer, the blocking base layer being attached to the first attachment region via the first adhesion layer; The reinforcing layer includes a reinforcing base layer and a second adhesive layer, the reinforcing base layer being attached to the second attachment region via the second adhesive layer; the blocking base layer includes a first body portion and a first extension portion connected to the first body portion, the first adhesive layer is for adhering at least a portion of the first body portion to the first attachment area, and the first extension portion protrudes from the first attachment area in a winding axis direction of the electrode assembly; the reinforcing base layer includes a second body portion and a second extension portion connected to the second body portion, the second adhesive layer is for adhering at least a portion of the second body portion to the second attachment area, the second extension portion protruding from the second attachment area in the winding axis direction, The winding axis direction is perpendicular to the winding direction, An electrode assembly, wherein the first extension portion and the second extension portion are connected via the first adhesive layer and / or the second adhesive layer.

2. The electrode assembly of claim 1 , wherein the Nth fold point includes a first fold point and / or a second fold point.

3. the electrode assembly has a straight region connected to the bent region; One end of the ion-blocking layer and the reinforcing layer extending along the winding direction is located in the straight region, and the other end is located in the bent region, or The electrode assembly according to claim 1 , wherein both ends of the ion-blocking layer and the reinforcing layer extending in the winding direction are located in the straight region.

4. the ion blocking layer includes a first adhesion layer, the first adhesion layer being attached to the first attachment region; 4. The electrode assembly of claim 1, wherein the reinforcing layer comprises a reinforcing base layer and a second adhesive layer, the reinforcing base layer being attached to the second attachment region via the second adhesive layer.

5. 2. The electrode assembly of claim 1, wherein the material of the blocking base layer includes at least one of polyvinyl chloride, polyethylene, polypropylene, polyvinylidene fluoride, hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoropropylene-vinylidene fluoride copolymer, trifluorochloropropylene-vinylidene fluoride copolymer, polyethylene terephthalate, polyimide, polyetherimide, polycarbonate, polystyrene, polyphenylene sulfide, polyvinylidene fluoride or a copolymer thereof, polyarylate, fiber, nylon, and nonwoven fabric.

6. 5. The electrode assembly according to claim 4, wherein the material of the first adhesive layer and / or the second adhesive layer includes at least one of an acrylic acid-acrylic acid ester copolymer, a butadiene-styrene copolymer, a styrene-acrylic acid copolymer, a styrene-acrylic acid ester copolymer, an ethylene-vinyl acetate copolymer, an acrylic acid grafted polyethylene, a maleic anhydride grafted polyethylene, an acrylic acid grafted polypropylene, a maleic anhydride grafted polypropylene, a polyvinylidene fluoride, a carboxymethyl cellulose, a polyimide, a polyetherimide, a polyethylene terephthalate, a styrene-isoprene-styrene copolymer rubber, an ethylene-vinyl acetate copolymer bisphenol A type epoxy resin, an ethylene-vinyl acetate copolymer bisphenol F type epoxy resin, a glyceryl ether type epoxy resin, a glyceryl ester type epoxy resin, a silicone-based resin, a polyurethane, and a styrene-isoprene-styrene copolymer.

7. 5. The electrode assembly of claim 4, wherein the material of the reinforcing base layer includes at least one of polyvinyl chloride, polyethylene, polypropylene, polyvinylidene fluoride, hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoropropylene-vinylidene fluoride copolymer, trifluorochloropropylene-vinylidene fluoride copolymer, polyethylene terephthalate, polyimide, polyetherimide, polycarbonate, polystyrene, polyphenylene sulfide, polyvinylidene fluoride or a copolymer thereof, polyarylate, fiber, nylon, and nonwoven fabric.

8. The electrode assembly of claim 1 , wherein the through hole extends through the reinforcing base layer and the second adhesive layer.

9. Adsorption regions and punch regions are arranged in the reinforcing layer along the winding direction, at least a portion of the through holes are distributed in the punch regions, and the porosity of the adsorption regions is smaller than the porosity of the punch regions, or The electrode assembly according to claim 1 , wherein the through holes are distributed in the reinforcing layer in a zigzag or curved line along a winding axis direction of the electrode assembly.

10. A battery cell comprising a housing, an electrolyte, a cover plate and at least one electrode assembly according to any one of claims 1 to 9, wherein: the housing has a receiving cavity and an opening, the electrode assembly and the electrolyte are received in the receiving cavity; The cover plate is for closing an opening in the housing.

11. A battery comprising: a housing; and at least one battery cell according to claim 10, said battery cell contained within said housing.

12. 12. A power consuming device configured to receive power from a battery according to claim 11.

13. A method for fabricating an electrode assembly for a lithium ion battery, comprising the steps of: a cathode plate, an anode plate, and a separator, the separator being for isolating the cathode plate and the anode plate, the cathode plate, the separator, and the anode plate being wound along a winding direction to form a folding region; the cathode plate is folded M times to form M folding points in the folding region; a first attachment area is formed on an inner surface of the Nth fold of the cathode plate, and a second attachment area is formed on an outer surface of the Nth fold, where M and N are positive integers, M≧2, and 1≦N≦M; providing an ion-blocking layer and a reinforcing layer; at least a portion of the ion-blocking layer is attached to the first attachment region, and the ion-blocking layer is for preventing ions released from the first attachment region from being occluded in an anode plate adjacent to the first attachment region during charging; at least a portion of the reinforcing layer is attached to the second attachment region, and an ion exchange passage is provided in the reinforcing layer, the ion exchange passage being a through hole provided along a thickness direction of the reinforcing layer; the ion blocking layer includes a blocking base layer and a first adhesion layer, the blocking base layer being attached to the first attachment region via the first adhesion layer; The reinforcing layer includes a reinforcing base layer and a second adhesive layer, the reinforcing base layer being attached to the second attachment region via the second adhesive layer; the blocking base layer includes a first body portion and a first extension portion connected to the first body portion, the first adhesive layer is for adhering at least a portion of the first body portion to the first attachment area, and the first extension portion protrudes from the first attachment area in a winding axis direction of the electrode assembly; the reinforcing base layer includes a second body portion and a second extension portion connected to the second body portion, the second adhesive layer is for adhering at least a portion of the second body portion to the second attachment area, the second extension portion protruding from the second attachment area in the winding axis direction, The winding axis direction is perpendicular to the winding direction, A method for processing an electrode assembly, wherein the first extension portion and the second extension portion are connected via the first adhesive layer and / or the second adhesive layer.

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