Current collector disc processing method, current collector disc, battery cell and electrical apparatus

Abstract

Disclosed in the present application are a current collector disc processing method, a current collector disc, a battery cell and an electrical apparatus. The current collector disc processing method comprises: a punching step of providing a first sheet material; a stacking step of providing a second sheet material and stacking the second sheet material and the first sheet material; a welding step of welding the first sheet material and the second sheet material in a welding area; and a cutting step of obtaining a current collector disc. According to the current collector disc processing method, the current collector disc, the battery cell and the electrical apparatus provided in the present application, the current collector disc is obtained by sequentially performing the punching step, the stacking step, the welding step and the cutting step without the need of providing a positioning structure on an annular piece and a connecting disc, thus helping to simplify the structure of the current collector disc, improving the position precision of the annular piece and the connecting disc in the current collector disc, and simplifying the production and assembling process of the current collector disc.

Description

Current collecting plate processing method, current collecting plate, battery cell and power-consuming device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 19, 2023, with application number 202311208692.4 and invention name “Current collecting plate processing method, current collecting plate, battery cell and electrical device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application belongs to the field of battery technology, and more specifically, relates to a current collecting disc processing method, a current collecting disc, a battery cell and an electrical device. Background Art

[0003] In related technologies, a cylindrical battery cell includes an electrode assembly, a negative electrode current collector, and a housing. The negative electrode tab of the electrode assembly is typically made of copper foil, while the housing is typically made of steel. The negative electrode current collector includes a copper sheet welded to the negative electrode tab and a steel sheet welded to the housing, with the copper and steel sheets welded together for electrical continuity. To ensure assembly accuracy of the current collector, multiple positioning structures are required on the copper and steel sheets to control the welding alignment of the copper and steel sheets, the alignment of the copper and negative electrode tabs, and the alignment of the steel and housing. This results in a complex structure, processing, and assembly of the current collector, affecting the efficiency of processing and assembly.

[0004] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0005] Application Contents

[0006] The purpose of the embodiments of the present application is to provide a current collecting plate processing method, a current collecting plate, a battery cell and an electrical device, including but not limited to solving the technical problems of complex processing and assembly of the current collecting plate in related applications.

[0007] The technical solution adopted in the embodiment of this application is:

[0008] In a first aspect, a method for processing a current collecting plate is provided, comprising the following steps:

[0009] A punching step, providing a first sheet material, wherein the first sheet material includes a pre-punching area, the pre-punching area is divided into an opening area and a welding area surrounding the opening area, and a first opening is formed in the opening area for receiving the tab;

[0010] a laminating step of providing a second sheet material, and laminating the second sheet material with the first sheet material so that the second sheet material covers the pre-punched area;

[0011] a welding step of welding the first sheet material and the second sheet material in the welding area;

[0012] a cutting step of cutting the first sheet material and the second sheet material along the edge of the pre-punching area to obtain a current collecting plate;

[0013] In the collecting plate, the part cut from the first sheet is an annular sheet, which is used to connect to the shell; the part cut from the second sheet is a connecting plate, which is used to connect to the pole ear; the part where the connecting plate and the annular sheet are welded together forms a weld mark area.

[0014] In the current collecting disc processing method provided in the embodiment of the present application, the first sheet and the second sheet are subjected to a punching step, a stacking step, a welding step and a cutting step to obtain a current collecting disc. Since the annular sheet and the connecting disc in the current disc have been welded together before cutting, the cutting edges of the annular sheet and the connecting disc can be kept aligned, so that the current collecting disc can be aligned with the pole ear and the shell at the same time during assembly. Compared with the method of first cutting the annular sheet and the connecting disc and then positioning and welding the annular sheet and the connecting disc, the current collecting disc in the present application does not need to be provided with a positioning structure on the annular sheet and the connecting disc, which is conducive to simplifying the structure of the current collecting disc, improving the position accuracy of the annular sheet and the connecting disc in the current collecting disc, simplifying the production and assembly process of the current collecting disc, and helping to improve production and assembly efficiency. Moreover, the processing method of the present application can improve the symmetry of the current collecting disc, and avoid affecting the welding accuracy of the current collecting disc with the pole ear and the shell due to the difference in the alignment of the annular sheet and the connecting disc in the current collecting disc.

[0015] In one embodiment, in the punching step: a plurality of the pre-punching areas are sequentially arranged along the length direction of the first sheet material, and the first opening is opened in the opening area of ​​each of the pre-punching areas.

[0016] By sequentially arranging a plurality of pre-punching areas along the length direction of the first sheet material and opening the first opening, the welding and cutting positions can be controlled to be arranged sequentially, thereby facilitating the processing of multiple annular sheets of current collecting plates.

[0017] In one embodiment, in the stacking step: the length direction of the second sheet material is kept the same as the length direction of the first sheet material, so that the second sheet material covers each of the pre-punched areas.

[0018] By covering the plurality of pre-punched areas with the second sheet material, it is possible to facilitate cutting to obtain the connecting plates of the plurality of current collecting plates, thereby improving the processing efficiency of the current collecting plates.

[0019] In one embodiment, after the laminating step, the method further includes: pressing the first sheet material and the second sheet material so that the first sheet material and the second sheet material remain flat at positions corresponding to the pre-punching area.

[0020] By pressing the first sheet material and the second sheet material after they are stacked, the first sheet material and the second sheet material can be kept flat and close to each other, so as to facilitate welding and cutting of the first sheet material and the second sheet material.

[0021] In one embodiment, in the welding step, before welding the first sheet material and the second sheet material, the step further includes:

[0022] The position of the first opening is identified, and the welding position of the first sheet material and the second sheet material in the welding area is determined according to the position of the first opening.

[0023] By determining the welding position according to the position of the first opening, it is possible to ensure that the welding position in each collecting plate is consistent with the position of its first opening, thereby avoiding the influence of the position deviation of the first sheet and the second sheet on the consistency of the relative position of the weld mark area and the first opening in the collecting plate.

[0024] In one embodiment, the cutting step further includes: forming a second opening on the second sheet material, and arranging the second opening coaxially with the first opening.

[0025] By adopting the second opening, the flow of electrolyte and the like can be facilitated.

[0026] In one embodiment, in the cutting step, before cutting the first sheet material and the second sheet material, the method further comprises:

[0027] The position of the first opening is identified, and the position of the edge of the pre-punching area and the position in the second sheet for forming the second opening are determined according to the position of the first opening.

[0028] By determining the position of the second opening and the corresponding cutting position of the periphery of the pre-punching area according to the position of the first opening, the relative positions of the first opening and the second opening on the collecting plate and the periphery of the collecting plate can be kept consistent, thereby improving the consistency and symmetry of the collecting plate.

[0029] In one embodiment, in the welding step, the first sheet material and the second sheet material are welded by using one of laser welding, penetration welding, resistance welding, thermal composite welding or friction welding.

[0030] By adopting the above-mentioned welding method, the first sheet material and the second sheet material can be welded together, ensuring that the first sheet material and the second sheet material are firmly welded.

[0031] In one embodiment, after the cutting step, the method further comprises:

[0032] Deburr the edges of the collecting pan.

[0033] By adopting the above technical means, the edge of the collecting plate can be kept smooth, which is beneficial to improving the welding quality during the assembly of the collecting plate.

[0034] In one embodiment, the circumference of the weld mark area is coaxially arranged with the first opening; and / or the outer periphery of the collecting plate is coaxially arranged with the first opening.

[0035] By adopting the above-mentioned technical means, the symmetry of the weld area on the current collecting disk can be improved. After the current collecting disk is welded to the tab and the shell, the resistance distribution of the first sheet and the second sheet in each direction can be uniform; the first opening is coaxial with the outer periphery of the current collecting disk, which can improve the symmetry of the current collecting disk and facilitate the alignment welding of the current collecting disk, the tab and the shell.

[0036] In one embodiment, the weld print area includes a plurality of weld segments.

[0037] By adopting the above technical means, it is possible to avoid unevenness of both surfaces of the collecting plate after welding due to high heat input during welding of the first sheet and the second sheet.

[0038] In one embodiment, the plurality of welding segments are arranged in a circular array; and / or,

[0039] The welding section is arc-shaped, and the central angle of the welding section relative to the first opening is 30°-120°; and / or,

[0040] The central angle of the first opening corresponding to the gap between two adjacent welding sections is 5°-60°; and / or,

[0041] The ratio of the width of the welding section to the width of the annular sheet is 0.2-0.9.

[0042] By adopting the above-mentioned technical means, the symmetry of the weld mark area can be improved, and the two sides of the collecting plate can be conveniently controlled to remain flat after welding; the length of each welding section can be guaranteed to reduce the number of welding times, ensure welding efficiency, disperse the heat input during welding, and ensure the flatness of the collecting plate; the spacing between adjacent welding sections can be controlled to ensure the resistance between the annular sheet and the connecting plate, and prevent the collecting plate from deforming after welding; controlling the width of the welding section can improve the stability of the connection between the annular sheet and the connecting plate, and is conducive to reducing resistance.

[0043] In one embodiment, the first sheet material is a tape material; and / or the second sheet material is a tape material.

[0044] The use of strip materials is beneficial to the continuous production of collecting plates.

[0045] In one embodiment, the material of the first sheet is the same as that of the housing; and / or,

[0046] The material of the second sheet is the same as that of the tab.

[0047] By adopting a first sheet material having the same material as the shell, the annular sheet and the shell can be made of the same material, which facilitates welding the shell and the annular sheet and improves the stability of welding the annular sheet and the shell; by adopting a second sheet material having the same material as the tab, the connecting plate and the tab can be made of the same material, which facilitates welding the tab and the connecting plate and improves the stability of welding the connecting plate and the tab.

[0048] In the second aspect, an embodiment of the present application also provides a collecting plate, comprising an annular sheet for connecting to a shell and a connecting plate for connecting to a pole ear, a weld mark area being formed between the annular sheet and the connecting plate, and a first opening being opened in the middle of the annular sheet; the annular sheet is formed by the portion cut from the first sheet, the connecting plate is formed by the portion cut from the second sheet, the weld mark area is formed by the welding portion of the first sheet and the second sheet, and the annular sheet is aligned with the outer periphery of the connecting plate.

[0049] By adopting the above technical means, the outer periphery of the annular sheet and the connecting plate in the collecting plate can be aligned, the structure of the collecting plate can be simplified, the assembly and alignment of the collecting plate can be facilitated, and the production and assembly efficiency of the collecting plate can be improved.

[0050] In one embodiment, a second opening is formed on the connection plate for electrolyte circulation, and the area of ​​the second opening is smaller than that of the first opening.

[0051] By adopting the above technical means, a certain area can be reserved for the tab welding at the position inside the first opening of the connecting disk corresponding to the connecting disk, so as to facilitate the welding of the connecting disk and the tab.

[0052] In one embodiment, the material of the annular sheet is the same as that of the housing; and / or,

[0053] The material of the connecting plate is the same as that of the tab.

[0054] By using an annular sheet made of the same material as the shell, the welding of the shell and the annular sheet can be facilitated, and the stability of the welding between the annular sheet and the shell can be improved; by using a connecting plate made of the same material as the tab, the welding of the tab and the connecting plate can be facilitated, and the stability of the welding between the connecting plate and the tab can be improved.

[0055] In a third aspect, an embodiment of the present application further provides a battery cell, comprising an electrode assembly and a shell, wherein the electrode assembly is provided with a positive electrode tab and a negative electrode tab, and further comprises the current collecting plate described in any of the above embodiments, wherein the negative electrode tab or the positive electrode tab is placed in the first opening and is welded to the connecting plate, and the shell is welded to the annular sheet.

[0056] By adopting the above technical means, the symmetry of the collecting plate is better, which helps to improve the consistency of the battery cells. The assembly of the collecting plate is more convenient, which is conducive to improving the production efficiency of the battery cells.

[0057] In a fourth aspect, an embodiment of the present application further provides an electrical device comprising the battery cell described in any of the above embodiments.

[0058] By adopting the above technical means, it is helpful to improve the stability of the operation of electrical devices and reduce the cost and production efficiency of electrical devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or exemplary technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0060] FIG1 is a schematic structural diagram of a vehicle according to some embodiments of the present application;

[0061] FIG2 is a schematic diagram of the exploded structure of a battery according to some embodiments of the present application;

[0062] FIG3 is an exploded view of a battery cell provided in one embodiment of the present application;

[0063] FIG4 is a schematic diagram of a method for processing a current collecting plate according to an embodiment of the present application;

[0064] FIG5 is a top view of the pre-punching area on the first sheet in an embodiment of the present application;

[0065] FIG6 is a top view of the first sheet obtained after the punching step in the embodiment of the present application;

[0066] FIG7 is a top view of the first sheet and the second sheet obtained after the welding step in the embodiment of the present application;

[0067] FIG8 is an enlarged view of the pre-punching area in FIG7;

[0068] FIG9 is a top view of a current collecting plate provided in an embodiment of the present application;

[0069] FIG10 is a schematic diagram of the three-dimensional structure of the current collecting plate provided in an embodiment of the present application.

[0070] Among them, the reference numerals in the figures are:

[0071] 1000-Vehicle; 100-Battery; 200-Controller; 300-Motor;

[0072] 10-collecting plate; 101-welding area; 1011-welding section; 11-first sheet; 110-annular sheet; 111-pre-punching area; 1111-welding area; 1112-opening area; 112-first opening; 12-second sheet; 120-connecting plate; 121-second opening;

[0073] 20 - battery cell; 21 - housing; 22 - electrode assembly; 221 - negative electrode tab; 222 - positive electrode tab; 23 - top cover;

[0074] 30-box; 31-first part; 32-second part. DETAILED DESCRIPTION

[0075] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0076] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0077] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0078] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0079] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0080] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0081] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0082] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0083] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As battery applications continue to expand, market demand is also growing.

[0084] In the related art, a cylindrical battery cell includes an electrode assembly, a current collector, and a housing. The electrode assembly is provided with a negative electrode tab and a positive electrode tab. The negative electrode tab is made of copper foil, and the housing is made of steel. The current collector includes a copper sheet and a steel sheet. The copper sheet is welded to the negative electrode tab, and the steel sheet is welded to the housing, thereby connecting the negative electrode tab and the housing. When assembling the battery cell, it is necessary to first align the copper sheet and the steel sheet and weld them to the negative electrode tab, and then weld the copper sheet to the negative electrode tab and the steel sheet to the housing. When welding the copper sheet and the steel sheet, due to the error in the alignment of the copper sheet and the steel sheet, when welding the current collector to the housing and the negative electrode tab, the alignment of the copper sheet and the negative electrode tab, as well as the alignment of the steel sheet and the housing, will be affected, affecting the consistency of the current collector assembly.

[0085] To this end, positioning structures are typically provided on the copper and steel sheets, for example, protrusions on the copper sheet and grooves on the steel sheet. These structures coordinate with each other to control the alignment of the copper and steel sheets. Providing positioning structures on the steel and copper sheets increases the complexity of the collector plate structure, and requires alignment control during assembly, which complicates and reduces the efficiency of processing and assembly.

[0086] Based on the above considerations, some embodiments of the present application provide a current collecting plate processing method, please refer to Figures 3 to 9, the current collecting plate processing method includes the steps of: S10 punching step, S20 stacking step, S30 welding step and S40 cutting step, by first welding the first sheet 11 and the second sheet 12 and then cutting to obtain the current collecting plate 10, because the first sheet 11 and the second sheet 12 have been welded during cutting, so that the positions of the cut annular sheet 110 and the connecting plate 120 remain fixed; and the edges of the annular sheet 110 and the connecting plate 120 are formed by cutting, so that the edges of the annular sheet 110 and the connecting plate 120 in the current collecting plate 10 can be aligned, so that there is no need to strictly control the alignment accuracy of the first sheet 11 and the second sheet 12 during welding, which reduces the welding alignment requirements, simplifies the structure of the current collecting plate 10, and is conducive to improving the alignment accuracy of the current collecting plate 10, improving the processing efficiency and assembly efficiency of the current collecting plate 10, and improving the assembly consistency of the current collecting plate 10 in the battery cell 20.

[0087] The collecting disc disclosed in the embodiment of the present application can be an electrical device for using a battery cell, a battery or a battery pack, and the collecting disc can be an electrical connection between the negative electrode tab and the shell in the battery cell. The electrical device can be, but is not limited to, a vehicle, a portable device, a laptop computer, a ship, a spacecraft, an electric toy and an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. Spacecraft include airplanes, rockets, space shuttles and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc.

[0088] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0089] Please refer to Figure 1, which is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head, or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating, and meeting the power requirements of the vehicle 1000 during operation.

[0090] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000 , but also as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0091] Please refer to Figure 2, which is an exploded view of a battery 100 according to an embodiment of the present application. The battery 100 comprises a housing 30 and a battery cell 20, with the battery cell 20 housed within the housing 30. The current collecting plate processing method is a process for producing the current collecting plate 10 in the battery cell 20.

[0092] The housing 30 is used to provide a storage space for the battery cells 20. The housing 30 can adopt various structures. In some embodiments, the housing 30 can include a first portion 31 and a second portion 32. The first portion 31 and the second portion 32 cover each other, and the first portion 31 and the second portion 32 together define a storage space for accommodating the battery cells 20. The second portion 32 can be a hollow structure with one end open, and the first portion 31 can be a plate-like structure. The first portion 31 covers the open side of the second portion 32, so that the first portion 31 and the second portion 32 together define a storage space; the first portion 31 and the second portion 32 can also be hollow structures with one side open, and the open side of the first portion 31 covers the open side of the second portion 32. Of course, the housing 30 formed by the first portion 31 and the second portion 32 can be of various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0093] In some embodiments, the box 30 may serve as part of the chassis structure of the vehicle 1000. For example, a portion of the box 30 may form at least a portion of the floor of the vehicle 1000, or a portion of the box 30 may form at least a portion of a cross member or a longitudinal member of the vehicle 1000.

[0094] Of course, in some embodiments, the battery 100 may not include the case 30 , but rather a plurality of battery cells 20 may be electrically connected and formed into a whole through necessary fixing structures before being assembled into the vehicle 1000 .

[0095] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 30. Of course, the battery 100 may also be a battery module formed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection, and then the multiple battery modules are further connected in series, in parallel, or in a hybrid connection to form an entire battery cell, which is then housed within the housing 30. The battery 100 may also include other functional components, such as a busbar for electrically connecting the multiple battery cells 20.

[0096] Each battery cell 20 may be a secondary battery or a primary battery. A secondary battery refers to a battery cell 20 that can be recharged to activate the active material after the battery cell 20 is discharged and can continue to be used. A primary battery refers to a battery cell 20 that cannot be recharged to activate the active material after the battery cell 20 is exhausted and can continue to be used. The battery cell 20 may also be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., but is not limited thereto. The battery cell 20 may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of another shape. Prismatic battery cells include square-shell battery cells, blade-shaped battery cells, and polygonal prismatic batteries. Polygonal prismatic batteries, for example, hexagonal prismatic batteries, are not particularly limited in this application.

[0097] For the convenience of description, the following embodiments are described using a method for processing a current collecting plate according to an embodiment of the present application.

[0098] Referring to FIG. 3 to FIG. 10 , the present application provides a method for processing a current collecting plate, which includes the following steps:

[0099] S10 punching step, providing a first sheet material 11, the first sheet material 11 includes a pre-punching area 111, the pre-punching area 111 is divided into an opening area 1112 and a welding area 1111, the welding area 1111 is arranged around the opening area 1112, and a first opening 112 for the tab to be fitted and placed is formed in the opening area 1112;

[0100] S20 lamination step, providing a second sheet material 12, and laminating the second sheet material 12 with the first sheet material 11 so that the second sheet material 12 covers the pre-punched area 111;

[0101] S30 welding step, welding the first sheet 11 and the second sheet 12 in the welding area 1111;

[0102] S40: cutting step, cutting the first sheet 11 and the second sheet 12 along the edge of the pre-punching area 111 to obtain the collecting plate 10;

[0103] In the collecting plate 10, the part cut from the first sheet 11 is the annular sheet 110, which is used to connect to the shell 21. The part cut from the second sheet 12 is the connecting plate 120, which is used to connect to the pole ear. The part where the annular sheet 110 and the connecting plate 120 are welded together forms the weld mark area 101.

[0104] It should be noted that the housing 21 can be made of a metal or alloy such as steel, nickel, aluminum, or copper; the tab can be made of another metal or alloy such as steel, nickel, aluminum, or copper. The current collecting plate 10 can be, but is not limited to, a negative electrode current collecting plate. The first opening 112 can be, but is not limited to, for receiving the negative electrode tab 221. The connection plate 120 in the current collecting plate 10 corresponding to the first opening 112 is welded to the negative electrode tab 221, thereby achieving electrical connection between the current collecting plate 10 and the negative electrode tab 221.

[0105] The first sheet material 11 may be a sheet material or a strip material. When the first sheet material 11 is a sheet material, the width of the sheet material is greater than or equal to the outer diameter of the current collecting tray 10, and the length of the sheet material is greater than the outer diameter of the current collecting tray 10. When the first sheet material 11 is a strip material, the width of the strip material is greater than or equal to the outer diameter of the current collecting tray 10, and the length of the strip material is greater than the outer diameter of the current collecting tray 10. The second sheet material 12 may be a sheet material or a strip material. When the second sheet material 12 is a sheet material, the width of the sheet material is greater than or equal to the outer diameter of the current collecting tray 10, and the length of the sheet material is greater than the outer diameter of the current collecting tray 10. When the second sheet material 12 is a strip material, the width of the strip material is greater than or equal to the outer diameter of the current collecting tray 10, and the length of the strip material is greater than the outer diameter of the current collecting tray 10.

[0106] The opening area 1112 corresponds to the first opening 112 and has the same shape as the first opening 112. The welding area 1111 is the area on the first sheet 11 surrounding the opening area 1112 and corresponding to one annular piece 110. The welding area 1111 has the same shape as the annular piece 110. The pre-punching area 111 is the area on the first sheet 11 corresponding to one annular piece 110 cut out. That is, the pre-punching area 111 is a circular area with an outer diameter equal to the outer diameter of the collecting plate 10. After the opening area 1112 within the pre-punching area 111 is removed, the remaining portion becomes the welding area 1111. The areas of both the first sheet 11 and the second sheet 12 are larger than the area of ​​the pre-punching area 111.

[0107] The first opening 112 can be a circular hole, a square hole, or a regular polygonal hole. The first opening 112 is larger than the cross-section of the tab. During assembly of the battery cell 20, the tab can be inserted into the first opening 112 to facilitate welding of the end face of the tab to the connection plate 120. The first opening 112 can be formed by punching, laser cutting, or other methods. In one embodiment, the first opening 112 is a circular hole, as a circular hole provides high symmetry.

[0108] In the stacking step S20, the second sheet 12 can be stacked on either side of the first sheet 11, and the second sheet 12 covers the pre-punched area 111. The projection of the second sheet 12 on the first sheet 11 can completely cover the pre-punched area 111. The width of the second sheet 12 can be greater than or equal to the width of the first sheet 11, so that alignment can be facilitated during stacking.

[0109] In the S30 welding step, the first sheet 11 and the second sheet 12 can be welded together at planes close to each other by welding methods such as laser welding, penetration welding, resistance welding, thermal composite or friction welding. Here, the first sheet 11 and the second sheet 12 are made of different materials. The S30 welding step welds the different materials together. Since the contact surfaces of the first sheet 11 and the second sheet 12 are parallel and the contact area is large, welding is easier and the consistency of the welding quality is better.

[0110] The weld mark area 101 is the planar area where the first sheet 11 and the second sheet 12 are welded and fused together in the welding step S30. That is, the planar area where the surface of the first sheet 11 that is within a corresponding welding area 1111 and close to the second sheet 12 is welded to the second sheet 12. The weld mark area 101 is smaller than or equal to the surface of the annular sheet 110 close to the connecting pad 120. When the area of ​​the weld mark area 101 is equal to the area of ​​the side of the annular sheet 110 close to the connecting pad 120, the entire surface of the annular sheet 110 close to the connecting pad 120 is welded to the connecting pad 120. When the area of ​​the weld mark area 101 is smaller than the area of ​​the side of the annular sheet 110 close to the connecting pad 120, the portion of the surface of the annular sheet 110 close to the connecting pad 120 is not welded to the connecting pad 120.

[0111] In the S40 cutting step, when cutting along the pre-punching area 111, it can be, but is not limited to, cutting by punching, laser cutting, or other cutting methods, and the cutting method can be the same as or different from the cutting method of the first opening 112. During cutting, the first sheet 11 and the second sheet 12 are cut through along the thickness direction of the first sheet 11 (the direction perpendicular to the XY axis plane in Figures 5 and 6), so that the position of the first sheet 11 corresponding to the pre-punching area 111 is cut from the first sheet 11 to form an annular sheet 110, and the position of the second sheet 12 corresponding to the pre-punching area 111 is cut from the second sheet 12 to form a connecting plate 120. Since the weld print area 101 is within the pre-punching area 111, the annular sheet 110 and the connecting plate 120 are welded together to form the collecting plate 10.

[0112] In the current collecting disc processing method provided in the embodiment of the present application, the first sheet 11 and the second sheet 12 are subjected to the S10 punching step, the S20 stacking step, the S30 welding step and the S40 cutting step to obtain the current collecting disc 10. Since the annular sheet 110 and the connecting disc 120 in the current collecting disc 10 have been welded together before cutting, the cutting edges of the annular sheet 110 and the connecting disc 120 can be kept aligned, so that the current collecting disc 10 can be aligned with the pole ear and the shell 21 at the same time during assembly. Compared with the processing method of first cutting the annular sheet and the connecting disc and then positioning and welding the annular sheet and the connecting disc, which requires setting positioning structures on the copper sheet and the steel sheet of the current collecting disc 10 to control the alignment and welding of the copper sheet and the steel sheet, the current collecting disc 10 in the present application does not need to set positioning structures on the annular sheet 110 and the connecting disc 120, which is conducive to simplifying the structure of the current collecting disc 10, improving the position accuracy of the annular sheet 110 and the connecting disc 120 in the current collecting disc 10, simplifying the production and assembly process of the current collecting disc 10, and improving the production and assembly efficiency. Moreover, the processing method of the present application can improve the symmetry of the collecting plate 10 and avoid affecting the welding accuracy of the collecting plate 10 with the tab and the shell 21 due to the difference in alignment between the annular sheet 110 and the connecting plate 120 in the collecting plate 10.

[0113] Referring to FIG. 3 to FIG. 7 , in one embodiment, in the punching step S10 , a plurality of pre-punching areas 111 are sequentially provided along the length direction X of the first sheet material 11 , and a first opening 112 is opened in the opening area 1112 of each pre-punching area 111 .

[0114] The distances between adjacent pre-punching areas 111 in the plurality of pre-punching areas 111 may be equal or unequal, and two adjacent pre-punching areas 111 may be tangent to each other or spaced apart. When the width of the first sheet 11 is roughly equal to the outer diameter of the collecting disk 10, the pre-punching area 111 on the first sheet 11 is set along the length direction X of the first sheet 11. This can facilitate the control of the cutting position of the first opening 112 and the collecting disk 10. When the width of the first sheet 11 is roughly twice the outer diameter of the collecting disk 10, the pre-punching area 111 can be set in two rows, each row of pre-punching areas 111 is arranged along the length direction X of the first sheet 11, and the two pre-punching areas 111 are arranged along the width direction Y of the first sheet 11. When the first sheet 11 is wider, multiple rows of pre-punching areas 111 can be set according to the width of the first sheet 11 and the outer diameter of the collecting disk 10. Each row of pre-punching areas 111 is arranged along the length direction X of the first sheet 11, and multiple pre-punching areas 111 are arranged along the width direction Y of the first sheet 11.

[0115] In the S10 punching step, the adjacent pre-punching areas 111 can be controlled to be tangent or spaced, and the size of the pre-punching area 111 can match the size of the collecting disc 10, so that the pre-punching area 111 matches the shell 21. In the S10 punching step, it is not necessary to accurately locate the position of the pre-punching area 111 or mark the boundary position of the pre-punching area 111. It is only necessary to ensure that the position interval of any two adjacent opening areas 1112 meets the spacing requirements of the two pre-punching areas 111. It can be understood that the length of the center line of the two opening areas 1112 is greater than or equal to the outer diameter of the collecting disc 10. In this way, an annular sheet 110 can be cut in each pre-punching area 111, avoiding the overlap of the cutting areas when the two adjacent collecting discs 10 are cut subsequently, and ensuring that each collecting disc 10 obtained by cutting remains intact. The pre-punching areas 111 can be arranged along the length direction X on the first sheet 11, or along the width direction Y on the first sheet 11, or arranged in an array on the first sheet 11, etc.

[0116] When the first sheet 11 is short and the number of pre-punched areas 111 is small, multiple first openings 112 may be punched simultaneously using multiple dies. When the first sheet 11 is long and the number of pre-punched areas 111 is relatively large, the first openings 112 may be punched sequentially using one or more dies to reduce the overall size of the die. When the first openings 112 are punched sequentially, one or more first openings 112 may be punched at a time, and the punching of the first openings 112 is not limited to one by one.

[0117] By sequentially arranging a plurality of pre-punching areas 111 along the length direction X of the first sheet 11 and opening the first opening 112 , the welding and cutting positions can be controlled to be arranged sequentially, thereby facilitating the processing of the annular sheets 110 of the plurality of collecting plates 10 .

[0118] Please refer to FIG. 3 to FIG. 9 . In one embodiment, in the lamination step S20 , the length direction of the second sheet material 12 is kept the same as the length direction X of the first sheet material 11 , so that the second sheet material 12 covers each pre-punched area 111 .

[0119] When both the first sheet 11 and the second sheet 12 are sheet materials, the second sheet 12 is stacked on the first sheet 11 so that the thickness direction of the second sheet 12 is the same as the thickness direction of the first sheet 11, and the second sheet 12 and the first sheet 11 are located on two parallel planes. The length direction of the second sheet 12 is the same as the length direction X of the first sheet 11, which can make the width direction of the second sheet 12 the same as the width direction Y of the first sheet 11, and the second sheet 12 and the first sheet 11 have a large overlapping area. When multiple pre-punched areas 111 are arranged along the length direction X of the first sheet 11, the second sheet 12 can cover the multiple pre-punched areas 111 arranged along the length direction X of the first sheet 11, thereby forming connection pads 120 corresponding to each pre-punched area 111 during cutting.

[0120] When at least one of the first and second sheets 11, 12 is a strip, the second sheet 12 is stacked on the first sheet 11 such that the thickness of the second sheet 12 corresponding to some of the pre-punched areas 111 is aligned with the thickness of the first sheet 11, and the portions of the second sheet 12 and the first sheet 11 corresponding to one or more pre-punched areas 111 are located on two parallel planes. The length direction of the second sheet 12 is aligned with the length direction X of the first sheet 11, at least at locations corresponding to one or more pre-punched areas 111. This allows the width direction of the second sheet 12 to be aligned with the width direction Y of the first sheet 11, resulting in a large overlap area between the second sheet 12 and the first sheet 11. When multiple pre-punched areas 111 are arranged along the length direction X of the first sheet 11, the second sheet 12 can sequentially cover the multiple pre-punched areas 111 arranged along the length direction X of the first sheet 11 during the stacking process, thereby forming connection pads 120 corresponding to each pre-punched area 111 during cutting.

[0121] In one embodiment, the first sheet 11 and the second sheet 12 have the same width, which facilitates alignment of the first sheet 11 and the second sheet 12. Of course, the width of the second sheet 12 can also be greater than the width of the first sheet 11 to cover each pre-punched area 111.

[0122] By covering each pre-punched area 111 with the second sheet material 12 , it is possible to facilitate cutting to obtain a plurality of connecting plates 120 of the current collecting plates 10 , thereby improving the processing efficiency of the current collecting plates 10 .

[0123] Please refer to FIG. 3 to FIG. 10 . In one embodiment, after the stacking step S20 , the method further includes: pressing the first sheet 11 and the second sheet 12 tightly so that the first sheet 11 and the second sheet 12 remain flat at positions corresponding to the pre-punching area 111 .

[0124] After the first sheet 11 and the second sheet 12 are aligned, the first sheet 11 and the second sheet 12 are pressed together so that the first sheet 11 and the second sheet 12 can be tightly attached together and remain flat. When pressing the first sheet 11 and the second sheet 12, the positions corresponding to one or more pre-punched areas 111 can be pressed together. It is not necessary to press the positions corresponding to all pre-punched areas 111 at the same time. It is only necessary to keep the first sheet 11 and the second sheet 12 corresponding to the corresponding pre-punched areas 111 pressed together during the welding step.

[0125] When the first sheet 11 and the second sheet 12 are sheet materials, when the first sheet 11 and the second sheet 12 are pressed together, the surface of the first sheet 11 and the surface of the second sheet 12 are in close contact. When the first sheet 11 and the second sheet 12 are strips released from a roll, by pressing the first sheet 11 and the second sheet 12 together, the positions of the first sheet 11 and the second sheet 12 corresponding to the pre-punching area 111 can be kept flat and in close contact with each other during welding.

[0126] When the first sheet 11 and the second sheet 12 are pressed, pressure may be applied to a portion other than the pre-punching area 111. When welding and cutting the first sheet 11 and the second sheet 12 corresponding to one pre-punching area 111, pressure may be applied to the first sheet 11 and the second sheet 12 corresponding to the adjacent pre-punching area 111 so that the first sheet 11 and the second sheet 12 are clamped.

[0127] By pressing the first sheet 11 and the second sheet 12 after stacking them, the first sheet 11 and the second sheet 12 can be kept flat and close to each other, so as to facilitate welding and cutting of the first sheet 11 and the second sheet 12 and prevent the collecting plate 10 from warping after cutting.

[0128] In one embodiment, in the welding step S30, before welding the first sheet 11 and the second sheet 12, the following steps are further included:

[0129] The position of the first opening 112 is identified, and the welding position of the first sheet 11 and the second sheet 12 in the welding area 1111 is determined according to the position of the first opening 112 .

[0130] Identifying the position of first opening 112 can be performed, but is not limited to, through a visual detection mechanism, such as a CCD camera. When determining the welding position, a coordinate system can be established with the center of first opening 112 as the origin, the length of first sheet 11 as the X-axis, and the width of first sheet 11 as the Y-axis. The corresponding position of the welding position in the XY coordinate system is determined, and then the welding position and welding trajectory are determined before welding. Of course, in other embodiments, the position of first opening 112 and the welding position can also be determined based on the position of first sheet 11.

[0131] The welding position of the first sheet 11 and the second sheet 12 within the welding area 1111 refers to the welding position when the weld mark 101 on the current collecting tray 10 is formed in the welding step S30. The welding position within the welding area 1111 is determined based on the position of the first opening 112 within the same pre-punching area 111, so that the position of the weld mark 101 in each current collecting tray 10 remains consistent relative to the position of the first opening 112. This is equivalent to testing the welding position on the first sheet 11 before each welding, which helps prevent the position of the weld mark 101 in the current collecting tray 10 from being affected by deviations in the position of the first opening 112 in the first sheet 11.

[0132] By determining the welding position according to the position of the first opening 112, it is possible to ensure that the welding position in each collecting plate 10 is consistent with the position of its first opening 112, thereby avoiding the influence of the position deviation of the first sheet 11 and the second sheet 12 on the consistency of the relative position of the weld mark area 101 and the first opening 112 in the collecting plate 10.

[0133] Referring to FIG. 3 to FIG. 10 , in one embodiment, the cutting step S40 further includes: forming a second opening 121 on the second sheet 12 , and arranging the second opening 121 coaxially with the first opening 112 .

[0134] The second opening 121 can be, but is not limited to, circular, rectangular, or regular polygonal. The second opening 121 is smaller than the first opening 112. The coaxial arrangement of the second opening 121 and the first opening 112 can be understood as the center of the second opening 121 being on the axis of the first opening 112. The area corresponding to the second opening 121 is staggered with the corresponding position of the tab, which facilitates welding of the tab to the connection plate 120.

[0135] The second opening 121 allows electrolyte to flow on both sides of the connecting plate 120 , preventing the connecting plate 120 from blocking the electrolyte from flowing to the side away from the tab after the current collecting plate 10 is welded to the shell 21 and the tab.

[0136] Please refer to Figures 3 to 10. In one embodiment, in the S40 cutting step, before cutting the first sheet 11 and the second sheet 12, it also includes: identifying the position of the first opening 112, and determining the edge position of the pre-punching area 111 and the position in the second sheet 12 for opening the second opening 121 according to the position of the first opening 112.

[0137] Identifying the position of first opening 112 can be performed, but is not limited to, through a visual detection mechanism, such as a CCD camera. While the positions of first sheet 11 and second sheet 12 remain unchanged during welding step S30 and cutting step S40, the cutting position in cutting step S40 can be determined based on the position of first opening 112 identified in welding step S30. The cutting position can be determined by using the center of first opening 112 as the origin of a coordinate system and determining a circular cutting path based on the radius of current collecting plate 10. Of course, in other embodiments, first opening 112 and the cutting position can also be determined based on the position of first sheet 11.

[0138] The edge of the pre-punching area 111 (coaxial with the outer periphery of the welding area 1111) is the boundary position of the cutting to form the collecting tray 10. The edge position of the pre-punching area 111 is determined by the position of the first opening 112 in the collecting tray 10, so that the edge of each collecting tray 10 is positioned consistently relative to the first opening 112. This is equivalent to testing the cutting position on the first sheet 11 before each cut, which helps prevent the relative position of the edge of the collecting tray 10 and the first opening 112 from being affected by deviations in the position of the first opening 112 in the first sheet 11.

[0139] The position in the second sheet material 12 for forming the second opening 121 is the position on the second sheet material 12 corresponding to the position where the second opening 121 is formed.

[0140] By determining the position of the second opening 121 and the corresponding cutting position of the outer periphery of the collecting plate 10 according to the position of the first opening 112, the relative positions of the first opening 112 and the second opening 121 on the collecting plate 10 and the outer periphery of the collecting plate 10 can be kept consistent, thereby improving the consistency and symmetry of the collecting plate 10.

[0141] Referring to FIG. 3 to FIG. 10 , in one embodiment, in the welding step S30 , the first sheet 11 and the second sheet 12 are welded by using one of laser welding, penetration welding, resistance welding, thermal composite welding or friction welding.

[0142] In the S30 welding step, laser welding, penetration welding, resistance welding, thermal composite welding, or friction welding can achieve surface-to-surface fusion welding between the first sheet 11 and the second sheet 12, forming a larger weld mark 101. In one embodiment, in the S30 welding step, laser welding is used to weld the first sheet 11 and the second sheet 12 to form the weld mark 101. Laser welding can control energy intensity, width, and trajectory to facilitate the position and width of the weld mark 101, helping to reduce deformation on both sides of the collecting plate 10. Laser welding offers high consistency, high speed, and a mature process.

[0143] By adopting the above-mentioned welding method, the first sheet material 11 and the second sheet material 12 can be welded together, ensuring that the first sheet material 11 and the second sheet material 12 are firmly welded.

[0144] Please refer to FIG. 3 to FIG. 10 . In one embodiment, after the cutting step S40, the following steps are further included:

[0145] The edges of the collecting pan 10 are deburred.

[0146] Deburring can be done manually or mechanically, such as by grinding, milling, laser cleaning, etc., to remove sharp corners or burrs on the edge of the collector plate 10, thereby making the edges of the annular plate 110 and the connecting plate 120 more rounded and smooth. When welding the tabs to the housing 21, maintaining a smooth surface on the collector plate 10 can improve welding quality.

[0147] By polishing the collecting tray 10 , the edge of the collecting tray 10 can be kept smooth, thereby preventing the collecting tray 10 from scratching other collecting trays 10 or the housing 21 during production and assembly, and facilitating subsequent assembly.

[0148] 3 to 10 , in one embodiment, the circumference of the weld mark area 101 is coaxially disposed with the first opening 112 ; and / or the outer periphery of the current collecting plate 10 is coaxially disposed with the first opening 112 .

[0149] The circumference of the weld mark area 101 can be understood as the circumference of the inscribed circle of the weld mark area 101 . The radial width of the weld mark area 101 along the collecting plate 10 can be ignored. The weld mark area 101 can be understood as a curve surrounding the first opening 112 .

[0150] The outer circumference of the current collecting tray 10 refers to the circumference formed on the current collecting tray 10 when the first sheet 11 and the second sheet 12 are cut to form the current collecting tray 10 .

[0151] The circumference of the weld mark area 101 is coaxial with the first opening 112, which can improve the symmetry of the weld mark area 101 on the current collecting disc 10. After being welded to the tab and the shell 21, the resistance distribution of the current collecting disc 10 in all directions can be uniform; the first opening 112 is coaxial with the outer circumference of the current collecting disc 10, which can improve the symmetry of the current collecting disc 10 and facilitate the alignment welding of the current collecting disc 10 with the tab and the shell 21.

[0152] Referring to FIG. 3 to FIG. 10 , in one embodiment, the weld print area 101 includes a plurality of welding segments 1011 .

[0153] The number of welding segments 1011 can be 2, 3, 6, or 8. Multiple welding segments 1011 can be, but are not limited to, identical in shape. Welding segments 1011 can be arc-shaped, circular, elliptical, or rectangular, and adjacent welding segments 1011 can be spaced apart. Multiple welding segments 1011 are arranged around first opening 112, and the spacing between welding segments 1011 can vary. Different welding segments 1011 can be welded simultaneously or in multiple passes.

[0154] The weld mark area 101 is formed by a plurality of welding sections 1011 , which can avoid unevenness on both sides of the collecting plate 10 after welding due to high heat input during welding of the first sheet 11 and the second sheet 12 .

[0155] Referring to FIG. 3 to FIG. 10 , in one embodiment, a plurality of welding segments 1011 are arranged in a circular array; and / or,

[0156] The welding section 1011 is arc-shaped, and the central angle β of the welding section 1011 relative to the first opening 112 is 30°-120°; and / or,

[0157] The central angle α of the first opening 112 corresponding to the gap between two adjacent welding segments 1011 is 5°-60°; and / or,

[0158] The ratio of the width of the welding section 1011 to the width of the annular sheet 110 is 0.2-0.9.

[0159] The plurality of welding segments 1011 are arranged in an annular array, such as a multi-point annular array or a multi-arc annular array. On the one hand, the shapes of the welding segments 1011 are roughly the same, and on the other hand, the distances between adjacent welding segments 1011 are roughly the same, so that the formed weld mark area 101 has a high degree of symmetry.

[0160] In one embodiment, in the welding step S30 , multiple welding segments 1011 can be formed by welding the first sheet 11 and the second sheet 12 around the first opening 112 , and the welding parameters of each welding segment 1011 are kept consistent, so that the energy input of each welding segment 1011 is controlled to be consistent.

[0161] β can be 40°, 60°, 80°, or 100°. The arc shape of the weld segment 1011 means that, without considering the radial dimension of the weld segment 1011 along the collecting plate 10, the weld segment 1011 can be considered a smoothly curved line, such as an arc centered at the center of the first opening 112. The central angle β of the weld segment 1011 relative to the first opening 112 is the angle formed by two radial line segments, formed by connecting the center of the circle with the midpoint of the first opening 112 and the ends of the weld segment 1011, on the side closest to the weld segment 1011.

[0162] α can be 10°, 20°, 30°, 40°, or 50°, etc. The gap between two adjacent welding segments 1011 refers to the area between the ends of the two adjacent welding segments 1011. The corresponding central angle α refers to the angle between two radial line segments formed by connecting the center of the circle and the adjacent ends of the two adjacent welding segments 1011 with the midpoint of the first opening 112 as the center.

[0163] The ratio of the width of the welding section 1011 to the width of the annular sheet 110 can be 0.3, 0.5, 0.7 or 0.8. The width of the welding section 1011 refers to the radial dimension of the welding section 1011 along the collecting plate 10. The width of each part of the welding section 1011 can be different.

[0164] Arranging the welding segments 1011 in a circular array can improve the symmetry of the weld mark area 101 and can make the heat input during welding more evenly distributed, making it easier to control the flatness of both sides of the current collecting plate 10 after welding. Controlling the length range of the welding segments 1011 can, on the one hand, ensure the length of each welding segment 1011, so as to reduce the number of welding times and ensure welding efficiency. On the other hand, it can prevent the welding segments 1011 from being too long, which affects the heat input during welding and causes the two sides of the current collecting plate 10 to be uneven after welding. Controlling the spacing between adjacent welding segments 1011 controls the resistance between the annular sheet 110 and the connecting plate 120, and disperses the heat during welding, preventing the current collecting plate 10 from deforming after welding. Controlling the width of the welding segments 1011 can improve the stability of the connection between the annular sheet 110 and the connecting plate 120 and help reduce resistance.

[0165] Please refer to FIG. 3 to FIG. 10 . In one embodiment, the first sheet material 11 is a tape material; and / or the second sheet material 12 is a tape material.

[0166] Strip material refers to a material whose length is much greater than its width, and whose width is much greater than its thickness, such as a length greater than or equal to 4, 5, or 7 times its width. The strip material can be wound into a coil or flattened into a long strip. When using automated equipment to produce the collecting tray 10, the strip material can be provided with multiple pre-punching areas 111. The strip material can be transported by a conveyor mechanism so that the strip material passes through each processing position in sequence.

[0167] The first sheet 11 is made of a strip, and the pre-punching area 111 can be continuously provided on the first sheet 11, reducing the number of times the first sheet 11 needs to be replaced, thereby facilitating the continuous production of the collecting tray 10. The second sheet 12 is made of a strip, and can be continuously stacked, welded, and cut with the first sheet 11, reducing the number of times the second sheet 12 needs to be replaced, thereby facilitating the continuous production of the collecting tray 10.

[0168] Please refer to FIG. 3 to FIG. 10 . In one embodiment, the material of the first sheet 11 is the same as that of the housing 21 ; and / or the material of the second sheet 12 is the same as that of the tab.

[0169] The shell 21 and the first sheet 11 can be made of a metal or alloy such as steel, nickel, aluminum or copper. The first sheet 11 and the shell 21 are made of the same material. When the annular sheet 110 is welded to the shell 21, the welding quality of the same material can more easily ensure the welding quality of the collecting plate 10 and the shell 21; the tab and the second sheet 12 can be made of another metal or alloy such as steel, nickel, aluminum or copper. The tab and the shell 21 are made of different materials, and the second sheet 12 and the tab are made of the same material. When the connecting plate 120 is welded to the tab, the welding quality of the same material can more easily ensure the welding quality of the collecting plate 10 and the tab.

[0170] By adopting a first sheet material 11 made of the same material as the shell 21, the annular sheet 110 can be made of the same material as the shell 21, which facilitates welding the shell 21 and the annular sheet 110 and improves the stability of welding the annular sheet 110 and the shell 21; by adopting a second sheet material 12 made of the same material as the tab, the connecting plate 120 can be made of the same material as the tab, which facilitates welding the tab and the connecting plate 120 and improves the stability of welding the connecting plate 120 and the tab.

[0171] Please refer to Figures 3 to 10. The embodiment of the present application also provides a collecting plate 10, which includes an annular sheet 110 for connecting to the shell 21 and a connecting plate 120 for connecting to the pole ear. A weld print area 101 is formed between the annular sheet 110 and the connecting plate 120, and a first opening 112 is opened in the middle of the annular sheet 110; the first sheet 11 and the second sheet 12 are stacked and welded together by cutting, the annular sheet 110 is formed by the cut portion of the first sheet 11, the connecting plate 120 is formed by the cut portion of the second sheet 12, the weld print area 101 is formed by the welding portion of the first sheet 11 and the second sheet 12, and the outer periphery of the annular sheet 110 is aligned with the outer periphery of the connecting plate 120.

[0172] The current collecting plate 10 may be, but is not limited to, a negative electrode current collecting plate. The current collecting plate 10 may be an accessory manufactured by the above-mentioned current collecting plate processing method, or may be a component produced at a certain stage in the production line of the battery cell 20 .

[0173] The first and second sheets 11, 12 are cut and welded together. After the second sheet 12 and the first sheet 11 having the first opening 112 are stacked, the first and second sheets 11, 12 are welded around the first opening 112. After the first and second sheets 11, 12 are welded securely, the first and second sheets 11, 12 are cut. When the annular sheet 110 and the connecting plate 120 are cut, the outer peripheries of the annular sheet 110 and the connecting plate 120 are aligned. The current collecting plate 10 in this embodiment can be manufactured using the current collecting plate manufacturing method described in any of the above embodiments.

[0174] By adopting the current collecting plate processing method in the above embodiment, the outer periphery of the annular sheet 110 and the connecting plate 120 in the current collecting plate can be aligned, the structure of the current collecting plate 10 is simplified, the assembly and alignment of the current collecting plate 10 are facilitated, the production and assembly efficiency of the current collecting plate 10 is improved, and it helps to improve the consistency of the battery cell 20.

[0175] Referring to FIG. 3 to FIG. 10 , in one embodiment, a second opening 121 for electrolyte circulation is formed on the connection plate 120 , and the area of ​​the second opening 121 is smaller than that of the first opening 112 .

[0176] In one embodiment, the first opening 112 and the second opening 121 are circular holes, the outer diameter of the second opening 121 is smaller than the outer diameter of the first opening 112, and the second opening 121 is coaxially arranged with the first opening 112. An annular region is formed between the first opening 112 and the second opening 121 on the connecting plate 120, and the tab is welded to the annular region.

[0177] By opening the second opening 121, the flow of electrolyte can be facilitated; by controlling the area of ​​the second opening 121 to be smaller than the area of ​​the first opening 112, a certain area can be reserved for the electrode tab welding at the position of the connecting plate 120 corresponding to the first opening 112, so as to facilitate the welding of the connecting plate 120 and the electrode tab.

[0178] 3 to 10 , in one embodiment, the material of the annular sheet 110 is the same as that of the housing 21 ; and / or the material of the connecting plate 120 is the same as that of the tab.

[0179] The shell 21 and the annular sheet 110 can be made of a metal or alloy such as steel, nickel, aluminum or copper. The annular sheet 110 and the shell 21 are made of the same material. When the annular sheet 110 and the shell 21 are welded, the welding quality of the same material can more easily ensure the welding quality of the collecting plate 10 and the shell 21; the pole ear and the connecting plate 120 can be made of another metal or alloy such as steel, nickel, aluminum or copper. The pole ear and the shell 21 are made of different materials, and the connecting plate 120 and the pole ear are made of the same material. When the connecting plate 120 and the pole ear are welded, the welding quality of the same material can more easily ensure the welding quality of the collecting plate 10 and the pole ear.

[0180] By adopting an annular sheet 110 made of the same material as the shell 21, the welding of the shell 21 and the annular sheet 110 can be facilitated, and the stability of the welding between the annular sheet 110 and the shell 21 can be improved; by adopting a connecting plate 120 made of the same material as the pole tab, the welding of the pole tab and the connecting plate 120 can be facilitated, and the stability of the welding between the connecting plate 120 and the pole tab can be improved.

[0181] An embodiment of the present application also provides a battery cell 20, which includes an electrode assembly 22 and a shell 21, wherein the electrode assembly 22 is provided with a positive electrode tab 222 and a negative electrode tab 221, and further includes the current collecting plate 10 in any of the above embodiments, wherein the negative electrode tab 221 is placed in the first opening 112 and is welded to the connecting plate 120, and the shell 21 is welded to the annular sheet 110; alternatively, the positive electrode tab 222 is placed in the first opening 112 and is welded to the connecting plate 120, and the shell 21 is welded to the annular sheet 110.

[0182] The shell 21 is welded to the side of the annular sheet 110 away from the connecting plate 120 , which can increase the welding surface, improve the welding quality, and reduce the resistance of the welding part.

[0183] The electrode assembly 22 may be, but is not limited to, cylindrical and may be composed of, but is not limited to, a wound positive electrode sheet, a negative electrode sheet, and a separator. The positive electrode tab 222 and the negative electrode tab 221 may be disposed at either end of the electrode assembly 22. The battery cell 20 may also include a top cover 23, which is mounted on the end of the housing 21 away from the current collecting plate 10.

[0184] By adopting the current collecting plate 10 in the above embodiment, when the connecting plate 120 is connected to the negative electrode tab 221, it is convenient to weld the current collecting plate 10 with the negative electrode tab 221 and the shell 21. When the connecting plate 120 is connected to the positive electrode tab 222, it is convenient to weld the current collecting plate 10 with the positive electrode tab 222 and the shell 21, which helps to improve the consistency of the battery cell 20, makes the assembly of the current collecting plate 10 more convenient, and is conducive to improving the production efficiency of the battery cell 20.

[0185] An embodiment of the present application further provides an electrical device, comprising the battery cell 20 described in any of the above embodiments.

[0186] The number of the battery cells 20 may be one or more. When there are multiple battery cells 20 , they may be electrically connected to form a battery pack or a battery group.

[0187] By adopting the battery cell 20 in the above embodiment, it is helpful to improve the operational stability of the electric device and reduce the cost and production efficiency of the electric device.

[0188] Please refer to Figures 3 to 9. An embodiment of the present application provides a method for processing a collecting plate. The method for processing a collecting plate is performed by opening a first opening 112 on a first sheet 11, overlapping a second sheet 12 with the first sheet 11, and then welding and cutting to form a collecting plate 10. The edges of the annular sheet 110 and the connecting plate 120 in the collecting plate 10 after cutting can be aligned, which is beneficial to simplifying the processing process of the collecting plate 10 and improving the consistency of the collecting plate 10.

[0189] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for processing a current collecting plate, wherein: The steps include: A punching step, providing a first sheet material, the first sheet material comprising a pre-punching area, dividing the pre-punching area into an opening area and a welding area surrounding the opening area, and forming a first opening in the opening area for the tab to be inserted; a laminating step of providing a second sheet material, and laminating the second sheet material with the first sheet material so that the second sheet material covers the pre-punching area; A welding step of welding the first sheet material and the second sheet material in the welding area; a cutting step of cutting the first sheet material and the second sheet material along the edge of the pre-punching area to obtain a current collecting plate; In the current collecting plate, the part cut from the first sheet is an annular sheet used to connect to the shell, and the part cut from the second sheet is a connecting plate used to connect to the pole ear. The welding area is formed by the part where the connecting plate is welded to the annular sheet.

2. The current collecting plate processing method according to claim 1, wherein: In the punching step: a plurality of the pre-punching areas are sequentially arranged along the length direction of the first sheet material, and the first opening is opened in the opening area of ​​each of the pre-punching areas.

3. The current collecting plate processing method according to claim 2, wherein: In the stacking step: the length direction of the second sheet material is kept the same as the length direction of the first sheet material, so that the second sheet material covers each of the pre-punching areas.

4. The current collecting disk processing method according to any one of claims 1 to 3, wherein: After the stacking step, the method further includes: pressing the first sheet material and the second sheet material tightly so that the first sheet material and the second sheet material are kept flat at positions corresponding to the pre-punching area.

5. The current collecting disk processing method according to any one of claims 1 to 4, wherein: In the welding step, before welding the first sheet material and the second sheet material, the step further includes: The position of the first opening is identified, and the welding position of the first sheet material and the second sheet material in the welding area is determined according to the position of the first opening.

6. The current collecting disk processing method according to any one of claims 1 to 5, wherein: The cutting step also includes: forming a second opening on the second sheet material, and arranging the second opening coaxially with the first opening.

7. The method for processing a current collecting disk according to claim 6, wherein: In the cutting step, before cutting the first sheet material and the second sheet material, the method further includes: The position of the first opening is identified, and the position of the edge of the pre-punching area and the position in the second sheet material for forming the second opening are determined according to the position of the first opening.

8. The method for processing a current collecting disk according to any one of claims 1 to 7, wherein: In the welding step: the first sheet material and the second sheet material are welded by using one of the welding methods selected from the group consisting of laser welding, penetration welding, resistance welding, thermal composite welding and friction welding.

9. The method for processing a current collecting disk according to any one of claims 1 to 8, wherein: After the cutting step, the method further comprises: Deburr the edges of the collector plate.

10. The method for processing a current collecting disk according to any one of claims 1 to 9, wherein: The circumference of the weld mark area is coaxially arranged with the first opening; and / or the outer periphery of the collecting plate is coaxially arranged with the first opening.

11. The method for processing a current collecting disk according to any one of claims 1 to 10, wherein: The weld print area includes a plurality of weld segments.

12. The method for processing a current collecting plate according to claim 11, wherein: The plurality of welding segments are arranged in a circular array; and / or, The welding section is arc-shaped, and the central angle of the welding section corresponding to the first opening is 30°-120°; and / or, The central angle of the gap between two adjacent welding sections corresponding to the first opening is 5°-60°; and / or, The ratio of the width of the welding section to the width of the annular sheet is 0.2-0.

9.

13. The method for processing a current collecting disk according to any one of claims 1 to 12, wherein: The first sheet material is a tape material; and / or the second sheet material is a tape material.

14. The method for processing a current collecting disk according to any one of claims 1 to 13, wherein: The material of the first sheet is the same as that of the housing; and / or, The material of the second sheet is the same as that of the tab.

15. A collecting tray, wherein: It includes an annular sheet for connecting to a shell and a connecting plate for connecting to a pole ear, a weld mark area is formed between the annular sheet and the connecting plate, and a first opening is opened in the middle of the annular sheet; the annular sheet is formed by the portion cut from the first sheet, the connecting plate is formed by the portion cut from the second sheet, the weld mark area is formed by the welding portion of the first sheet and the second sheet, and the annular sheet is aligned with the outer periphery of the connecting plate.

16. The collector tray of claim 15, wherein: The connection plate is provided with a second opening for electrolyte circulation, and the area of ​​the second opening is smaller than the area of ​​the first opening.

17. The collector tray according to claim 15 or 16, wherein: The material of the annular sheet is the same as that of the shell; and / or, The material of the connecting plate is the same as that of the tab.

18. A battery cell, comprising an electrode assembly and a housing, wherein the electrode assembly is provided with a positive electrode tab and a negative electrode tab, wherein: It also includes the current collecting plate as described in any one of claims 15 to 17, wherein the negative electrode tab or the positive electrode tab is placed in the first opening and is welded to the connecting plate, and the shell is welded to the annular sheet.

19. An electrical device, wherein: Comprising the battery cell as claimed in claim 18.

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