CN220710390U

CN220710390U - Electrode assembly, processing equipment, battery cell, battery and electricity utilization device

Info

Publication number: CN220710390U
Application number: CN202420051677.7U
Authority: CN
Inventors: 王家昌
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2024-01-09
Filing date: 2024-01-09
Publication date: 2024-04-02
Anticipated expiration: 2034-01-09

Abstract

The application provides an electrode assembly, processing equipment, a battery cell, a battery and an electric device. The electrode assembly is a wound structure, and the electrode assembly includes: a main body portion including two end surfaces disposed opposite to each other in a first direction, the end surfaces including a first region and a second region connected to each other; the pole lugs are connected to the first area of the main body part. The electrode assembly is of a winding structure, the electrode assembly comprises a main body and electrode lugs, the main body comprises two end faces which are oppositely arranged in the first direction, the end faces comprise a first area and a second area which are mutually connected, the electrode lugs are arranged in the first area, electrolyte can be quickly immersed into the main body through the second area of the end faces, electrolyte immersion efficiency of the electrode assembly is improved, and battery performance is improved.

Description

Electrode assembly, processing equipment, battery cell, battery and electricity utilization device

Technical Field

The application relates to the technical field of batteries, in particular to an electrode assembly, processing equipment, a battery cell, a battery and an electric device.

Background

Along with the rising of new energy industry, lithium batteries are rapidly developed, and at present, in order to enable the batteries to have higher discharge multiplying power and cost performance, the cost can be effectively controlled, and the lithium batteries mostly adopt a full-tab process. In the full tab process of the lithium battery, the full tab is firstly arranged and flattened, and can be welded later after certain strength is achieved.

In the prior art, after the tab is kneaded flat, electrolyte cannot enter the battery cell rapidly, and the problems of low pole piece infiltration efficiency and poor pole piece infiltration exist.

Disclosure of Invention

In view of the above, the present application provides an electrode assembly, a processing device, a battery cell, a battery and an electric device, which can improve the impregnation efficiency of an electrolyte in the electrode assembly and improve the reliability of the battery.

In a first aspect, the present application provides an electrode assembly for use in a cylindrical battery, the electrode assembly being of a rolled configuration, the electrode assembly comprising: a main body portion including two end surfaces disposed opposite to each other in a first direction, the end surfaces including a first region and a second region connected to each other; the pole lugs are connected to the first area of the main body part.

In the technical scheme of this embodiment, electrode assembly is winding structure, and electrode assembly includes main part and utmost point ear, and main part is including two terminal surfaces that set up relatively in first direction, and the terminal surface includes interconnect's first region and second region, and the utmost point ear all sets up in first region, then in the electrolyte can be through the second region quick immersion main part of terminal surface, improves electrode assembly's electrolyte infiltration efficiency, improves battery performance.

In some embodiments, the body portion includes a central bore disposed therethrough in the first direction, at least a portion of the second region being in communication with the central bore, and/or at least a portion of the second region extending to an edge of the end face.

In the technical solution of the embodiment of the application, at least part of the second area is communicated with the central hole, and/or at least part of the second area extends to the edge of the end surface, so that when the electrolyte is immersed in the second area, the second area can be communicated with the central hole or the edge of the electrode assembly, so that the immersion rate of the electrolyte on the main body part of the electrode assembly is improved.

In some embodiments, one end of the second region extends to the edge of the end face, and the other end thereof communicates with the central bore.

In the technical scheme of this application embodiment, second regional one end extends to the edge of terminal surface, and its other end and centre bore intercommunication reduce the machining precision requirement of utmost point ear, improve electrode assembly's preparation efficiency, and second regional intercommunication centre bore and electrode assembly edge to improve the infiltration rate of electrolyte in the electrode assembly.

In some embodiments, the plurality of first regions are spaced around the central aperture.

In the technical scheme of this application embodiment, a plurality of first regions encircle the centre bore interval setting, and the regional setting of second is between adjacent first region, improves the regional area of second, improves the immersion rate of electrolyte, and the regional even distribution of second on the terminal surface to make things convenient for the even infiltration electrode assembly of electrolyte.

In some embodiments, the first region and the second region nest with each other.

In the technical scheme of the embodiment of the application, the preparation difficulty of the electrode assembly is simplified, the area of the second area is increased, and the infiltration rate of the electrolyte is improved.

In some embodiments, the tab includes a fixed end and a free end, the fixed end is connected to the first region of the main body portion, the free end extends toward the center of the end face, and the free end covers the second region of the portion in projection of the end face.

In the technical scheme of this embodiment, the utmost point ear includes stiff end and free end, and the stiff end is connected in the first region of main part, and the free end extends towards the center of terminal surface and sets up, and the free end covers partial second region at the projection of terminal surface to reduce the shielding of the regional partial utmost point ear of second to the second region of stretching into, make things convenient for the electrolyte to infiltrate electrode assembly's main part by the second region, improved electrode assembly's electrolyte infiltration rate, improved electrode assembly's reliability.

In some embodiments, the tab includes a first segment connected to the first region of the body portion and extending in a first direction, a second segment connected between the first segment and the second segment, and a weakened segment extending in a radial direction of the end face.

In the technical scheme of this embodiment, the utmost point ear includes first segmentation, second segmentation and weakening segmentation, first segmentation is connected in the first region of main part and is extended along first direction, weakening segmentation is connected between first segmentation and second segmentation, the radial direction of terminal surface is extended along to the second segmentation, through setting up weakening segmentation, so that each utmost point ear all buckles in weakening segmentation department, reduce the processing degree of difficulty of utmost point ear, and improve electrode assembly's utmost point ear uniformity, and can improve the utmost point ear interconnect because first region, lead to the problem of electrolyte infiltration difficulty in first region.

In a second aspect, an embodiment of the present application provides a processing apparatus for processing an electrode assembly according to the above first aspect, where the processing apparatus includes a processing area, a frame mechanism, and a rolling structure, the processing area is configured to carry the electrode assembly provided by the above first aspect, the plurality of frame mechanisms are disposed around the processing area, the rolling structure is connected to the frame mechanism, the rolling structure includes a sliding portion and a rolling portion, the sliding portion is slidably connected to the frame mechanism, and the rolling portion is connected to an end of the sliding portion facing away from the frame mechanism and is rotatably disposed relative to the sliding portion.

In a third aspect, embodiments of the present application provide a battery cell, including the electrode assembly provided in the embodiment of the first aspect, where the electrode assembly is accommodated in the case.

In some embodiments, the device further comprises a cover plate, wherein the cover plate is welded with at least part of the lugs, a through hole is formed in the cover plate, and the through hole and at least part of the second area are communicated in the first direction.

In the technical scheme of this embodiment, apron and at least partial utmost point ear welded connection are provided with the through-hole on the apron, and through-hole and at least partial second region are along first direction intercommunication, and electrolyte gets into the second region of main part through the through-hole of apron in order to infiltrate electrode assembly to improve this battery monomer's electrolyte infiltration rate and infiltration reliability.

In a fourth aspect, embodiments of the present application provide a battery, including the battery cell provided in the embodiment of the third aspect.

In a fifth aspect, an embodiment of the present application provides an electrical device, including the battery provided in the above fourth aspect.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

FIG. 1 is a schematic view of a vehicle according to an embodiment of the present application;

fig. 2 is a schematic structural view of a battery module according to an embodiment of the present application;

fig. 3 is a schematic view of a battery module according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a battery cell according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of an electrode assembly according to an embodiment of the present application;

FIG. 6 is a top view of an end face of an electrode assembly provided in an embodiment of the present application;

FIG. 7 is a schematic view of the structure of a pole piece of an electrode assembly according to an embodiment of the present application;

fig. 8 is a top view of an end face of an electrode assembly provided in accordance with yet another embodiment of the present application;

fig. 9 is a top view of an end face of an electrode assembly provided in accordance with yet another embodiment of the present application;

FIG. 10 is a schematic view of the structure of a pole piece of an electrode assembly provided in an embodiment of the present application;

fig. 11 is a top view of an end face of an electrode assembly provided in accordance with yet another embodiment of the present application;

FIG. 12 is a schematic view of the structure of a pole piece of an electrode assembly provided in an embodiment of the present application;

fig. 13 is a schematic structural view of a tab of an electrode assembly according to an embodiment of the present application;

FIG. 14 is a schematic view of a processing apparatus according to an embodiment of the present disclosure;

fig. 15 is a schematic structural view of a rolling structure of a processing apparatus according to an embodiment of the present application;

fig. 16 is a schematic structural view of a battery cell according to an embodiment of the present disclosure;

fig. 17 is a schematic structural view of a cover of a battery cell according to an embodiment of the present disclosure.

Reference numerals illustrate:

1. a vehicle; 2. a battery; 101. a motor; 102. a controller; 202. a case; 2021. a first box portion; 2022. a second box portion; 201. a battery module; 3. a battery cell; 31. a cover plate; 311. a through hole; 4. a housing;

5. an electrode assembly; 51. a main body portion; 52. a tab; 53. a pole piece; 54. an end face; 55. a central bore; 561. a first region; 562. a second region; 521. a first segment; 522. a second segment; 523. weakening the segments; 57. a base;

6. a top cover assembly; 7. processing equipment; 71. a frame mechanism; 72. a roll-in structure; 721. a sliding part; 722. and (5) rolling the press part.

Detailed Description

Embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical solutions of the present application, and thus are only examples, and are not intended to limit the scope of protection of the present application.

It should be noted that unless otherwise indicated, technical or scientific terms used in the embodiments of the present application should be given the ordinary meanings as understood by those skilled in the art to which the embodiments of the present application belong.

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.

Furthermore, the technical terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like are to be construed broadly and may, for example, be fixedly connected, detachably connected, or be integrated; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of embodiments of the present application, unless explicitly specified and limited otherwise, a first feature "up" or "down" on a second feature may be that the first and second features are in direct contact, or that the first and second features are in indirect contact via an intermediary. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

Currently, the application of power batteries is more widespread from the development of market situation. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles, and the like, and a plurality of fields such as military equipment, aerospace, and the like. With the continuous expansion of the application field of the power battery, the market demand of the power battery is also continuously expanding.

In the present application, the battery cells may include lithium ion secondary battery cells, lithium ion primary battery cells, lithium sulfur battery cells, sodium lithium ion battery cells, sodium ion battery cells, or magnesium ion battery cells, and the embodiment of the present application is not limited thereto.

Reference to a battery in embodiments of the present 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 the present application may include a battery module or a battery pack, or the like. The battery generally includes a case for enclosing one or more battery cells. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive electrode plate, a negative electrode plate and a separator. The battery cell mainly relies on metal ions to move between the positive pole piece and the negative pole piece to work. The positive electrode plate comprises a positive electrode foil and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode foil; the positive electrode foil comprises a positive electrode current collecting part and a positive electrode lug connected to the positive electrode current collecting part, wherein the positive electrode current collecting part is coated with a positive electrode active material layer, and the positive electrode lug is not coated with the positive electrode active material layer. Taking a lithium ion battery as an example, the material of the positive electrode foil can be aluminum or stainless steel, the positive electrode active material layer comprises a positive electrode active material, and the positive electrode active material can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate and the like. The negative electrode plate comprises a negative electrode foil and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode foil; the negative electrode foil comprises a negative electrode current collecting part and a negative electrode tab connected to the negative electrode current collecting part, wherein the negative electrode current collecting part is coated with a negative electrode active material layer, and the negative electrode tab is not coated with the negative electrode active material layer. The anode foil may be made of copper, the anode active material layer includes an anode active material, and the anode active material may be carbon or silicon. The material of the separator may be PP (polypropylene) or PE (polyethylene), etc.

The problems of slow electrolyte infiltration speed and insufficient electrolyte infiltration amount exist in the preparation process of the partial cylindrical battery monomer, and the battery performance is affected.

The cylindrical battery cell adopts the full tab technology, and after the full tab is flattened, the full tab is required to be finished and flattened, and the subsequent welding can be performed after certain strength is achieved, after the tab is flattened, the tab is covered on the end face of the battery cell, electrolyte is prevented from infiltrating the battery cell, and the problems of low electrolyte infiltration speed and insufficient infiltration amount are caused.

Based on the above-mentioned problem, this application provides an electrode assembly, and electrode assembly is winding structure, and electrode assembly includes main part and utmost point ear, and main part is including two terminal surfaces that set up relatively in first direction, and the terminal surface includes interconnect's first region and second region, and utmost point ear all sets up in first region, and then electrolyte can be through in the second region of terminal surface soakage main part fast, improves electrode assembly's electrolyte infiltration efficiency, improves battery performance.

The technical scheme described in the embodiment of the application is applicable to batteries and power utilization devices using the batteries.

The electric device may be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, or the like. The vehicle can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the application does not limit the electric device in particular.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to the above-described batteries and electric devices, but may be applied to all batteries including a case and electric devices using the batteries, but for simplicity of description, the following embodiments are described by taking an electric vehicle as an example.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1 according to some embodiments of the present application. The vehicle 1 can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extending vehicle. The interior of the vehicle 1 is provided with a battery 2, which may be provided at the bottom or at the head or at the tail of the vehicle 1. The battery 2 may be used for power supply of the vehicle 1, for example, the battery 2 may serve as an operating power source of the vehicle 1. The vehicle 1 may also include a controller 102 and a motor 101, the controller 102 being configured to control a battery to power the motor 101, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1.

In some embodiments of the present application, the battery may not only serve as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, providing driving power for the vehicle 1 instead of or in part instead of fuel oil or natural gas.

To meet different demands for power use, the battery 2 may include a plurality of battery cells, which means the smallest units constituting a battery module or a battery pack. Multiple cells may be connected in series and/or parallel via electrode terminals for use in various applications. The battery 2 mentioned in the present application includes a battery module or a battery pack. The battery cells can be connected in series or parallel or in series-parallel connection, and the series-parallel connection refers to the mixture of series connection and parallel connection. In the embodiment of the application, a plurality of battery monomers can directly form a battery pack, or can form a battery module first, and the battery module forms the battery pack again.

Fig. 2 shows a schematic structural diagram of a battery 2 according to an embodiment of the present application.

As shown in fig. 2, the battery includes a case 202 and a battery cell (not shown) housed in the case 202.

The case 202 may have a simple three-dimensional structure such as a rectangular parallelepiped, a cylinder, or a sphere, or may have a complex three-dimensional structure formed by combining simple three-dimensional structures such as a rectangular parallelepiped, a cylinder, or a sphere. The material of the case 202 may be an alloy material such as aluminum alloy or iron alloy, a polymer material such as polycarbonate or polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin.

The case 202 is used to house the battery cells, and the case 202 may have various structures. In some embodiments, the case 202 may include a first case portion 2021 and a second case portion 2022, where the first case portion 2021 and the second case portion 2022 are mutually covered, and the first case portion 2021 and the second case portion 2022 together define an accommodating space for accommodating the battery cell 3. The second housing portion 2022 may be a hollow structure having one end opened, the first housing portion 2021 is a plate-like structure, and the first housing portion 2021 is covered on the opening side of the second housing portion 2022 to form the housing 202 having an accommodation space; the first housing portion 2021 and the second housing portion 2022 may each be a hollow structure having an opening at one side, and the opening side of the first housing portion 2021 is covered with the opening side of the second housing portion 2022 to form the housing 202 having the accommodation space. Of course, the first housing portion 2021 and the second housing portion 2022 may be of various shapes, such as a cylinder, a rectangular parallelepiped, or the like.

In order to improve the sealing property after the first housing portion 2021 and the second housing portion 2022 are connected, a sealing member, such as a sealant, a seal ring, or the like, may be provided between the first housing portion 2021 and the second housing portion 2022.

Assuming that the first housing portion 2021 is covered on top of the second housing portion 2022, the first housing portion 2021 may also be referred to as an upper cover, and the second housing portion 2022 may also be referred to as a lower cover.

In the battery 2, the number of battery cells may be one or more. If the number of the battery cells is multiple, the multiple battery cells can be connected in series or in parallel or in series-parallel connection, and the series-parallel connection means that the multiple battery cells are connected in series or in parallel. The plurality of battery cells can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells is accommodated in the box 202; of course, a plurality of battery cells may be connected in series or parallel or in series to form the battery module 201, and then the plurality of battery modules 201 are connected in series or parallel or in series to form a whole and are accommodated in the case 202.

Fig. 3 shows a schematic structural view of a battery module 201 according to an embodiment of the present application.

In some embodiments, as shown in fig. 2 and 3, the battery cells 3 are plural, and the plural battery cells 3 are first connected in series or parallel or series-parallel to form the battery module 201. The plurality of battery modules 201 are then connected in series or parallel or a series-parallel combination to form a unit and are accommodated in the case 202.

The plurality of battery cells 3 in the battery module 201 may be electrically connected through a bus bar member to realize parallel connection or series-parallel connection of the plurality of battery cells 3 in the battery module 201.

In the present application, the battery cell 3 may include a lithium ion battery cell 3, a sodium ion battery cell 3, a magnesium ion battery cell 3, or the like, which is not limited in the embodiment of the present application.

Fig. 4 is a schematic structural diagram of a battery cell 3 according to some embodiments of the present application. The battery cell 3 refers to the smallest unit constituting the battery. As shown in fig. 4, the battery cell 3 includes a top cap assembly 6, a case 4, and an electrode assembly 5.

The electrode assembly 5 is a component in which electrochemical reactions occur in the battery cells 3. One or more electrode assemblies 5 may be contained within the case 4.

The case 4 is an assembly for cooperating with the top cap assembly 6 to form an internal environment of the battery cell 3, wherein the formed internal environment may be used to accommodate the electrode assembly 5, an electrolyte (not shown in the drawings), and other components. The case 4 and the top cap assembly 6 may be separate members, and an opening may be provided in the case 4 to form an internal environment of the battery cell 3 by covering the opening with the top cap assembly 6 at the opening. Alternatively, the top cover assembly 6 and the housing 4 may be integrated. Alternatively, the cap assembly 6 and the housing 4 may be formed with a common connection surface prior to the other components being housed, and the cap assembly 6 is then allowed to cover the housing 4 when it is desired to encapsulate the interior of the housing 4. The material of the housing 4 may be various, and optionally, the material of the housing 4 may be copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

Referring to fig. 5 to 7, fig. 5 is a schematic structural view of an electrode assembly according to an embodiment of the present application; FIG. 6 is a top view of an end face of an electrode assembly provided in an embodiment of the present application; fig. 7 is a schematic structural view of a pole piece of an electrode assembly according to an embodiment of the present application.

In a first aspect, as shown in fig. 5 to 7, the present application provides an electrode assembly 5 applied to a cylindrical battery 2, the electrode assembly 5 being of a wound structure, the electrode assembly 5 including a main body portion 51 and a tab 52, the main body portion 51 including two end faces 54 disposed opposite to each other in a first direction X, the end faces 54 including a first region 561 and a second region 562 connected to each other; the tabs 52 are each connected to a first region 561 of the main body 51.

In the technical scheme of this embodiment, electrode assembly 5 is winding structure, and electrode assembly 5 includes main part 51 and utmost point ear 52, and main part 51 includes two terminal surfaces 54 that set up relatively in first direction X, and terminal surface 54 includes interconnect's first region 561 and second region 562, and utmost point ear 52 all set up in first region 561, and then electrolyte can be through the quick immersion in main part 51 of the second region 562 of terminal surface 54, improves electrode assembly 5's electrolyte infiltration efficiency, improves battery 2 performance.

The electrode sheet 53 is divided into a positive electrode sheet 53 and a negative electrode sheet 53, and a separator is generally provided between the positive electrode sheet 53 and the negative electrode sheet 53. The portions of the positive electrode sheet 53 and the negative electrode sheet 53 having the active material constitute the base 57, and the portions of the positive electrode sheet 53 and the negative electrode sheet 53 having no active material constitute the tab 52. The positive electrode tab 52 and the negative electrode tab 52 may be located at one end of the main body 51 or at both ends of the base 57. During charge and discharge of the battery 2, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 52 connects the electrode terminals to form a current loop. The electrode assembly 5 is formed by winding a pole piece 53, and the main body 51 of the electrode assembly 5 is formed by winding a base 57, and the tab 52 is connected to the main body 51 of the electrode assembly 5.

In this embodiment, the pole piece 53 of the full tab 52 is die-cut, that is, a notch is cut in the full tab 52 of the pole piece 53, and then the pole piece 53 is wound to form the electrode assembly 5, where the notch of the pole piece 53 is located in the second area 562 and each tab 52 is located in the first area 561 on the end surface 54 of the electrode assembly 5. In other words, in the first region 561 of the end surface 54, the tab 52 is connected to the base 57 of the pole piece 53 wound into the main body 51, and the tab 52 is not connected to the base 57 located in the second region 562. Since the tab 52 is not provided on the base 57 in the second region 562, the electrolyte can be conveniently infiltrated into the main body 51 from the second region 562 of the end surface 54.

Or, after the full tab 52 pole piece 53 is wound into the battery 2 assembly, the tab 52 in the second region 562 of the end face 54 is cut to form a notch, so that the electrolyte can infiltrate into the main body 51 from the second region 562 of the end face 54.

Optionally, one or more second areas 562 disposed at intervals may be disposed on the end surface 54, and in order to increase the area of the second areas 562 and speed up the infiltration rate of the electrolyte, a plurality of gaps may be disposed in the second areas 562 along the radial direction of the end surface 54. The number of notches and the notch length on the end face 54 can be flexibly set.

Optionally, the second region 562 on the main body 51 extends radially and/or circumferentially along the end surface 54, i.e. the indentations on the end surface 54 extend radially and/or circumferentially along the end surface 54.

Alternatively, the area of the first region 561 should be larger than the area of the second region 562 in consideration of the overcurrent capability of the tab 52.

Referring to fig. 8, fig. 8 is a top view of an end surface of an electrode assembly according to another embodiment of the present application.

In some embodiments, as shown in fig. 5 and 8, the body portion 51 includes a central bore 55 disposed therethrough in the first direction X, at least a portion of the second region 562 communicates with the central bore 55, and/or at least a portion of the second region 562 extends to an edge of the end face 54.

In these embodiments, at least a portion of the second region 562 communicates with the central bore 55, and/or at least a portion of the second region 562 extends to the edge of the end face 54 such that when electrolyte is immersed in the second region 562, it can communicate to the central bore 55 or to the edge of the electrode assembly 5 to increase the rate of electrolyte immersion into the body portion 51 of the electrode assembly 5.

A central hole 55 penetrates through the main body portion 51 of the electrode assembly 5, the central hole 55 is used for accommodating a winding needle in the winding process of the pole piece 53, the end face 54 of the main body portion 51 is annular, and electrolyte can infiltrate the pole piece 53 through the central hole 55.

The second region 562 and the center hole 55 are communicated by cutting out a part of the tab 52 at the end of the pole piece 53 so that the second region 562 is located at the outer edge portion of the end face 54, or the edge portion of the center hole 55.

At least a portion of the second region 562 communicates with the central bore 55, and/or at least a portion of the second region 562 extends to an edge of the end face 54. A second region 562 communicating with the central bore 55 is provided on the end face 54 or a second region 562 extending to the edge of the end face 54 is provided on the end face 54 or both the second region 562 communicating with the central bore 55 and the second region 562 extending to the edge of the end face 54 are included on the end face 54.

In other embodiments, as shown in fig. 5 and 8, the second region 562 extends from one end to the edge of the end face 54 and the other end communicates with the central bore 55.

In these embodiments, one end of the second region 562 extends to the edge of the end surface 54, the other end thereof communicates with the central hole 55, the processing precision requirement of the tab 52 is reduced, the preparation efficiency of the electrode assembly 5 is improved, and the second region 562 communicates with the central hole 55 and the edge of the electrode assembly 5, so as to improve the infiltration rate of the electrolyte in the electrode assembly 5.

The tabs 52 from the central hole 55 to the edge of the end surface 54 are cut away along the radial direction of the end surface 54, so as to reduce the preparation precision requirement of the second region 562. Or a plurality of notches are arranged on the tab 52 at intervals before the pole piece 53 is wound, and the notches are radially arranged along the end surface 54 after winding to form a second region 562.

Referring to fig. 9 and 10, fig. 9 is a top view of an end surface of an electrode assembly according to still another embodiment of the present application; fig. 10 is a schematic structural view of a pole piece of an electrode assembly according to an embodiment of the present application.

In some embodiments, as shown in fig. 5, 8-10, a plurality of first areas 561 are spaced around the central bore 55.

In these embodiments, a plurality of first areas 561 are spaced around the central hole 55, second areas 562 are disposed between adjacent first areas 561, the area of the second areas 562 is increased, the immersion rate of the electrolyte is increased, and the second areas 562 on the end surface 54 are uniformly distributed to facilitate uniform immersion of the electrolyte into the electrode assembly 5.

Optionally, each first region 561 is uniformly disposed around the central hole 55, and each first region 561 has the same size, so that each second region 562 has a uniform area, so as to facilitate uniform wetting of the electrode assembly 5 by the electrolyte.

Alternatively, as shown in fig. 9, a plurality of tabs 52 are radially arranged in the first region 561, and the linear distance between the two ends of each segment is the same in the circumferential direction of the end face 54, so that the first region 561 is rectangular, and the rectangular first region 561 facilitates welding of the tabs 52 and the cover plate 31.

Referring to fig. 11 and 12, fig. 11 is a top view of an end surface of an electrode assembly according to still another embodiment of the present application; fig. 12 is a schematic structural view of a pole piece of an electrode assembly according to an embodiment of the present application.

In some embodiments, as shown in fig. 5, 11 and 12, the first region 561 and the second region 562 are nested with each other.

The first area 561 and the second area 562 are sleeved with each other, which means that at least one first area 561 is circumferentially arranged at one side of at least one second area 562 facing the edge of the end surface 54, or at least one second area 562 is circumferentially arranged at one side of at least one first area 561 facing the edge of the end surface 54. Illustratively, each of the first regions 561 and each of the second regions 562 are disposed around the central bore 55, with each of the first regions 561 and each of the second regions 562 being spaced apart along the radial direction of the end face 54.

In these embodiments, the difficulty in preparing the electrode assembly 5 is simplified, the area of the second region 562 is increased, and the infiltration rate of the electrolyte is increased.

The end surface 54 includes a second region 562, or a plurality of second regions 562 nested within one another. Before the pole piece 53 is wound, a notch is cut off on the pole lug 52, and a second area 562 is formed after winding, so that the operation is simple and convenient, and the processing difficulty is low.

Optionally, a second region 562 is disposed around the central bore 55 to allow electrolyte to pass through the second region 562 into the central bore 55, or the second region 562 is disposed around the edge of the end face 54.

In some embodiments, as shown in fig. 5, 11 and 12, the tab 52 includes a fixed end connected to the first region 561 of the main body 51 and a free end extending toward the center of the end face 54, the free end projecting over a portion of the second region 562 of the end face 54.

In these embodiments, the tab 52 includes a fixed end and a free end, the fixed end is connected to the first region 561 of the main body 51, the free end extends toward the center of the end face 54, and the projection of the free end on the end face 54 covers part of the second region 562, so as to reduce the shielding of the second region 562 by the tab 52 extending into the second region 562, facilitate the electrolyte to infiltrate the main body 51 of the electrode assembly 5 from the second region 562, improve the electrolyte infiltration rate of the electrode assembly 5, and improve the reliability of the electrode assembly 5.

After the electrode tab 53 is wound into the electrode assembly 5, the tab 52 is connected to the main body 51 and extends in the first direction X, and then the tab 52 needs to be flattened so that the free end of the tab 52 extends toward the region of the central hole 55. When the second region 562 and the first region 561 are arranged along the radial direction of the end surface 54, the free end of the tab 52 covers a part of the second region 562, and by adjusting the area of the second region 562, the projection of the tab 52 on the end surface 54 can only cover a part of the second region 562, so that the electrolyte can infiltrate the main body 51 from the uncovered part of the second region 562.

Referring to fig. 13, fig. 13 is a schematic structural view of a tab of an electrode assembly according to an embodiment of the present disclosure.

In some embodiments, as shown in fig. 5, 6 and 13, the tab 52 includes a first segment 521, a second segment 522, and a weakened segment 523, the first segment 521 being connected to the first region 561 of the body portion 51 and extending in the first direction X, the weakened segment 523 being connected between the first segment 521 and the second segment 522, the second segment 522 extending in the radial direction of the end face 54.

In these embodiments, the tab 52 includes the first segment 521, the second segment 522 and the weakened segment 523, the first segment 521 is connected to the first region 561 of the main body 51 and extends along the first direction X, the weakened segment 523 is connected between the first segment 521 and the second segment 522, and the second segment 522 extends along the radial direction of the end face 54, by providing the weakened segment 523, each tab 52 is bent at the weakened segment 523, so as to reduce the processing difficulty of the tab 52, improve the uniformity of the tab 52 of the electrode assembly 5, and improve the problem that the electrolyte is difficult to wet in the first region 561 due to the interconnection of the tab 52 of the first region 561.

Alternatively, the weakened section may be a crease formed on the tab 52, or the weakened section of the tab 52 is provided with a through hole 311, so as to reduce the structural strength of the weakened section of the tab 52, and when the tab 52 is flattened, the tab 52 is easier to bend along the weakened section.

Referring to fig. 14 and 15, fig. 14 is a schematic structural diagram of a processing apparatus according to an embodiment of the present disclosure; fig. 15 is a schematic structural view of a rolling structure of a processing apparatus according to an embodiment of the present application.

In a second aspect, as shown in fig. 14 and 15, the embodiment of the present application provides a processing apparatus 7 for processing the electrode assembly 5 of the embodiment of the first aspect, the processing apparatus 7 includes a processing area for carrying the electrode assembly 5 provided in the embodiment of the first aspect, a frame mechanism 71, and a rolling structure 72, the plurality of frame mechanisms 71 are disposed around the processing area, the rolling structure 72 is connected to the frame mechanism 71, the rolling structure 72 includes a sliding portion 721 and a rolling portion 722, the sliding portion 721 is slidably connected to the frame mechanism 71, and the rolling portion 722 is connected to an end of the sliding portion 721 facing away from the frame mechanism 71 and is rotatably disposed relative to the sliding portion 721.

The electrode assembly 5 is disposed in the processing area, the rolling structure 72 includes a sliding portion 721 and a rolling portion 722, the sliding portion 721 and the frame mechanism 71 are slidably connected such that the sliding portion 721 can move from the edge of the end surface 54 to the center of the end surface 54 in the radial direction of the end surface 54 through a slide rail, and the rolling portion 722 can be a roller connected to the sliding portion 721 such that the roller rolls the tab 52 when the sliding portion 721 moves along the slide rail.

Referring to fig. 16 and 17, fig. 16 is a schematic structural view of a battery cell according to an embodiment of the present disclosure; fig. 17 is a schematic structural view of a cover of a battery cell according to an embodiment of the present disclosure.

In some embodiments, as shown in fig. 5, 6, 16 and 17, the device further includes a cover plate 31, where the cover plate 31 is welded to at least a portion of the tab 52, and a through hole 311 is disposed on the cover plate 31, and the through hole 311 and at least a portion of the second area 562 are communicated along the first direction X.

In these embodiments, the cover plate 31 and at least part of the tab 52 are welded, the cover plate 31 is provided with a through hole 311, the through hole 311 and at least part of the second region 562 are communicated along the first direction X, and the electrolyte enters the second region 562 of the main body 51 via the through hole 311 of the cover plate 31 to infiltrate the electrode assembly 5, so as to improve the electrolyte infiltration rate and infiltration reliability of the battery cell 3.

The cover plate 31 and the tab 52 are welded, and the through holes 311 and the second areas 562 on the cover plate 31 are correspondingly arranged, so that the electrolyte can infiltrate the main body 51 through the through holes 311 and the second areas 562.

Alternatively, the shape of the through hole 311 may be flexibly designed, and the through hole 311 may be rectangular, circular, elliptical, or the like.

Optionally, the projection of the through hole 311 in the first direction X coincides with the second region 562, so that the electrolyte enters the second region 562 from the through hole 311.

In some embodiments, as shown in fig. 1 to 17, the electrode assembly 5 is a wound structure, the electrode assembly 5 includes a body portion 51 and a tab 52, the body portion 51 includes two end faces 54 disposed opposite to each other in a first direction X, the body portion 51 includes a central hole 55 disposed therethrough in the first direction X, the end faces 54 include a first region 561 and a second region 562 connected to each other, one end of the second region 562 extends to an edge of the end face 54, and the other end thereof communicates with the central hole 55; the tabs 52 are connected to the first areas 561 of the main body 51, the first areas 561 are spaced around the central hole 55, the tabs 52 include a fixed end and a free end, the fixed end is connected to the first areas 561 of the main body 51, the free end extends toward the center of the end surface 54, and the free end covers the second areas 562 of the portions of the end surface 54.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the embodiments, and are intended to be included within the scope of the claims and description. In particular, the technical features mentioned in the respective embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. An electrode assembly for use in a cylindrical battery, the electrode assembly having a rolled configuration, the electrode assembly comprising:

a main body portion including two end faces disposed opposite to each other in a first direction, the end faces including a first region and a second region connected to each other, the main body portion including a center hole penetrating along the first direction, at least a part of the second region communicating with the center hole, and/or at least a part of the second region extending to an edge of the end face;

and the pole lugs are connected to the first area of the main body part.

2. The electrode assembly of claim 1, wherein one end of the second region extends to an edge of the end face and the other end thereof communicates with the central bore.

3. The electrode assembly of claim 2, wherein a plurality of said first regions are spaced around said central aperture.

4. The electrode assembly of claim 1, wherein the first region and the second region are nested with each other.

5. The electrode assembly of claim 4, wherein the tab includes a fixed end connected to the first region of the body portion and a free end extending toward a center of the end face, the free end covering a portion of the second region in a projection of the end face.

6. The electrode assembly of claim 1, wherein the tab comprises a first segment connected to the first region of the body portion and extending in a first direction, a second segment connected between the first segment and the second segment, and a weakened segment extending in a radial direction of the end face.

7. A machining apparatus for machining an electrode assembly according to any one of claims 1 to 6, characterized in that the machining apparatus comprises a machining region for carrying the electrode assembly according to any one of claims 1 to 6, a frame mechanism around which a plurality of the frame mechanisms are arranged, and a roll-in structure connected to the frame mechanism, the roll-in structure comprising a slide and a roll-in part, the slide and the frame mechanism being slidingly connected, the roll-in part being connected to an end of the slide facing away from the frame mechanism and being arranged rotatably relative to the slide.

8. A battery cell comprising a housing and the electrode assembly of any one of claims 1-6, wherein the electrode assembly is contained within the housing.

9. The battery cell of claim 8, further comprising a cover plate, wherein the cover plate is welded to at least a portion of the tab, wherein a through hole is formed in the cover plate, and wherein the through hole and at least a portion of the second region are in communication in the first direction.

10. A battery comprising a cell according to any one of claims 8-9.

11. An electrical device comprising a battery as claimed in claim 10.