CN117790875A

CN117790875A - Electrode assembly manufacturing apparatus and electrode assembly manufacturing method

Info

Publication number: CN117790875A
Application number: CN202410148418.0A
Authority: CN
Inventors: 谢媛媛; 冯保铭
Original assignee: Jiangsu Contemporary Amperex Technology Ltd
Current assignee: Jiangsu Contemporary Amperex Technology Ltd
Priority date: 2024-02-02
Filing date: 2024-02-02
Publication date: 2024-03-29

Abstract

The application relates to the technical field of batteries, and discloses manufacturing equipment and a manufacturing method of an electrode assembly. The first die cutting mechanism is used for die-cutting a plurality of preformed electrode lugs on the electrode plate; the winding mechanism is arranged at the downstream of the first die cutting mechanism and is used for winding the pole piece and the separator and laminating the preformed pole lugs; the second die cutting mechanism is arranged at the downstream of the winding mechanism and is used for die cutting the plurality of preformed tabs which are stacked to form a plurality of tabs. The manufacturing equipment of the electrode assembly can improve the machining precision and reliability of the electrode assembly.

Description

Electrode assembly manufacturing apparatus and electrode assembly manufacturing method

Technical Field

The present disclosure relates to the field of battery technologies, and in particular, to an apparatus and a method for manufacturing an electrode assembly.

Background

With the development of new energy technology, the battery is increasingly widely applied, for example, to mobile phones, notebook computers, battery cars, electric automobiles, electric airplanes, electric ships, electric toy automobiles, electric toy ships, electric toy airplanes, electric tools and the like.

The development of battery technology is an important research direction in the field of batteries, considering various design factors, such as how to improve the processing accuracy and reliability of the production of electrode assemblies in batteries.

Disclosure of Invention

The present application provides an electrode assembly manufacturing apparatus and a motor assembly manufacturing method, which can improve the processing precision and reliability of an electrode assembly.

In a first aspect, the present application provides an apparatus for manufacturing an electrode assembly, comprising a first die cutting mechanism for die cutting a plurality of preformed tabs on a pole piece, a winding mechanism, and a second die cutting mechanism; the winding mechanism is arranged at the downstream of the first die cutting mechanism and is used for winding the pole piece and the separator and laminating a plurality of preformed pole lugs; the second die cutting mechanism is arranged at the downstream of the winding mechanism and is used for die cutting a plurality of preformed tabs which are stacked to form a plurality of tabs.

In the technical scheme of this application embodiment, through set up two cross cutting mechanisms respectively in winding mechanism's upper and lower stream to carry out twice cutting by these two cross cutting mechanisms respectively to the utmost point ear of pole piece, can improve the position accuracy of utmost point ear effectively through the cross cutting mode of first rough cut, second finish cut, thereby improve electrode assembly's reliability.

According to some of the embodiments of the present application, a winding mechanism is used to wind the separator and the two pole pieces; the manufacturing equipment comprises two first die cutting mechanisms, wherein the two first die cutting mechanisms respectively die-cut the two pole pieces; the manufacturing equipment comprises two second die cutting mechanisms, wherein the two second die cutting mechanisms respectively die-cut preformed lugs of the two pole pieces. And a plurality of die cutting mechanisms are arranged simultaneously, and the die cutting mechanisms are in one-to-one correspondence with the pole pieces, so that the processing efficiency is improved.

In a second aspect, the present application provides a method of manufacturing an electrode assembly, comprising: die-cutting a plurality of preformed lugs on the pole piece; winding the pole piece and the separator, and laminating a plurality of preformed pole lugs; and die cutting the laminated plurality of preformed tabs to form a plurality of tabs. The dislocation caused by winding is eliminated by cutting after winding, and the position precision of the tab is effectively improved.

According to some of the embodiments of the present application, before the step of die cutting the plurality of preformed tabs on the pole piece, further comprises: acquiring a preset tab width of a pole piece; the step of die cutting a plurality of preformed tabs on the pole piece further comprises: the width of the preformed tab is made to be larger than the width of the preset tab. And selecting the width of the preformed tab according to the preset tab width, and flowing out sufficient space for the second die cutting.

According to some of the embodiments of the present application, the preset tab width is L1, the width of the preformed tab is L2, and the step of die-cutting the plurality of preformed tabs on the pole piece further includes: 1.2L1L 2 is less than or equal to 2L1. Proper width is selected for the preformed tab, and the influence on winding is reduced on the basis of compatibility with dislocation after winding.

According to some of the embodiments of the present application, between the step of winding the pole piece and separator and the step of die cutting the plurality of preformed tabs in a stacked arrangement further comprises: acquiring a preset tab width and a preset tab position of a pole piece; image acquisition is carried out on the preformed electrode lugs, and the overlapping width of the preformed electrode lugs and the preset electrode lug positions is obtained; judging whether the preformed tab is misplaced after winding according to the overlapping width and the preset tab width; the pole piece including the preformed tab with dislocation after winding is recovered or rewound. And identifying whether the offset is serious after the pole piece is wound, and the dislocation problem that the second cutting cannot be corrected is solved, and re-winding to correct, so that the reliability of the electrode assembly is further improved.

According to some embodiments of the present application, the step of determining whether the preformed tab is dislocated after winding according to the overlapping width and the preset tab width further includes: obtaining the maximum interval L5 between the positions of the pre-formed tabs staggered after winding and the preset tabs, and obtaining the number M of the pre-formed tabs arranged in a stacked manner; and adjusting the cutting positions in the step of die-cutting a plurality of preformed tabs on the pole piece, so that the cutting positions of the preformed tabs are moved by L6 and L6=L5/(M-1) in the direction opposite to the dislocation direction. The cutting parameters of the subsequent pole pieces are corrected according to the dislocation condition in the former winding matrix, so that the cutting position accuracy can be further improved.

According to some embodiments of the present application, the preset tab width is L1, the overlap width is L3, and the step of determining whether the preformed tab is dislocated after winding according to the overlap width and the preset tab width further includes: judging whether the overlapping width accords with L3 or not to be more than 0.5L1, if not, judging that the preformed tab is misplaced after winding. If the position deviation of the preformed tab and the preset tab exceeds the preset value, the dislocation problem is judged to exist so as to accurately correct the dislocation problem.

According to some embodiments of the present application, between the step of judging whether the preformed tab has a post-winding dislocation according to the overlapping width and the preset tab width and the step of unwinding and re-winding the pole piece including the preformed tab having the post-winding dislocation, the method further includes: obtaining the number N of preformed tabs which are arranged in a stacked manner and are staggered after winding; judging whether the number N accords with N less than or equal to 5, and if so, regarding the preformed tabs which are stacked as dislocation after winding does not occur. If the number of the dislocated tabs is small, the dislocated tabs can be regarded as no dislocation, so that the processing time is saved.

According to some of the embodiments of the present application, the step of image capturing the preformed tab includes: and adopting a charge coupled device camera to acquire images. And a charge coupled device camera with small volume, light weight and high image definition is adopted for shooting.

According to some of the embodiments of the present application, the step of die cutting the plurality of preformed tabs in a stacked arrangement further comprises: acquiring a preset tab width L1 of a pole piece and a preset tab position; the tab is trimmed to ensure that the distance L4 between the edge of the tab and the edge of the preset tab position in the width direction is less than or equal to 0.25L1. And correcting and repairing the tab again after cutting, so that the position and size accuracy of the tab are further improved.

According to some of the embodiments of the present application, the step of die cutting the plurality of preformed tabs on the pole piece comprises: providing two pole pieces, and respectively cutting out a plurality of preformed pole lugs on the two pole pieces; the step of winding the pole piece and separator comprises: the preformed lugs of the two pole pieces are respectively overlapped. During winding, the two pole pieces can be wound together at the same time and subjected to secondary die cutting at the same time so as to improve the processing efficiency

According to some of the embodiments of the present application, the step of die cutting the plurality of preformed tabs in a stacked arrangement further comprises: and recovering the pole piece residual materials obtained by cutting in the step of die-cutting a plurality of preformed pole lugs on the pole piece and the step of die-cutting a plurality of preformed pole lugs which are arranged in a stacked manner. The waste materials generated by cutting can be recycled so as to reduce the processing cost.

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 accompanying drawings. In the drawings:

fig. 1 is a schematic structural view of a manufacturing apparatus of an electrode assembly according to an embodiment of the present application;

FIG. 2 is a flow chart of a method of manufacturing an electrode assembly according to one embodiment of the present application;

fig. 3 is a schematic structural diagram corresponding to step S1 shown in fig. 2;

fig. 4 is a schematic structural diagram corresponding to step S3 shown in fig. 2;

FIG. 5 is a flow chart of a method of manufacturing an electrode assembly according to another embodiment of the present application;

FIG. 6 is a partial flow chart of a method of manufacturing an electrode assembly according to one embodiment of the present application;

fig. 7 is a partial flowchart of a method of manufacturing an electrode assembly according to another embodiment of the present application.

Reference numerals:

100-manufacturing equipment;

10-pole pieces; 20-a first die cutting mechanism; 30-a winding mechanism; 40-a second die cutting mechanism;

11-preforming the tab; 12-electrode lugs; 13-spacers.

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.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, the technical terms "first," "second," etc. are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, which means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural sheets" refers to two or more (including two).

In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of describing the embodiments of the present application and for simplifying the description, rather than indicating or implying that the apparatus or element 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.

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 be, for example, fixedly connected, detachably connected, or integrally formed; 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 this embodiment of the present application, the battery cell may be a secondary battery cell, and the secondary battery cell refers to a battery cell that can activate the active material by charging after discharging the battery cell and continue to use.

The battery cell may be a lithium ion battery cell, a sodium lithium ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium sulfur battery cell, a magnesium ion battery cell, a nickel hydrogen battery cell, a nickel cadmium battery cell, a lead storage battery cell, etc., which the embodiment of the application is not limited to.

The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode and a negative electrode. During the charge and discharge of the battery cell, active ions (e.g., lithium ions) are inserted and extracted back and forth between the positive electrode and the negative electrode.

In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode, which may function to prevent the positive electrode and the negative electrode from being shorted, while allowing the active ions to pass through.

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

As an example, the positive electrode current collector has two surfaces opposing in its own thickness direction, and the positive electrode active material layer is provided on either one or both of the two surfaces opposing the positive electrode current collector.

In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector.

As an example, a lithium source material, which is a lithium metal and/or a lithium-rich material, potassium metal, or sodium metal, may also be filled and/or deposited within the negative electrode current collector.

In some embodiments, the material of the positive electrode current collector may be aluminum and the material of the negative electrode current collector may be copper.

In some embodiments, the electrode assembly further includes a separator disposed between the positive and negative electrode sheets.

In some embodiments, the separator is a separator film. The type of the separator is not particularly limited, and any known porous separator having good chemical stability and mechanical stability may be used.

In some embodiments, the separator is a solid state electrolyte. The solid electrolyte is arranged between the positive plate and the negative plate and plays roles in transmitting ions and isolating the positive plate and the negative plate.

In some embodiments, the battery cell further includes an electrolyte that serves to conduct ions between the positive and negative electrodes. The type of electrolyte is not particularly limited in this application, and may be selected according to the need. The electrolyte may be liquid, gel or solid.

In some embodiments, the electrode assembly is a rolled structure. The positive plate and the negative plate are wound into a winding structure.

In some embodiments, the electrode assembly is a lamination stack.

As an example, a plurality of positive electrode sheets and negative electrode sheets may be provided, respectively, and a plurality of positive electrode sheets and a plurality of negative electrode sheets may be alternately stacked.

As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheets are folded to form a plurality of folded sections arranged in a stacked manner, with one positive electrode sheet sandwiched between adjacent folded sections.

As an example, the positive and negative electrode sheets are each folded to form a plurality of folded sections in a stacked arrangement.

As an example, the separator may be provided in plurality, respectively between any adjacent positive electrode sheet or negative electrode sheet.

As an example, the separator may be continuously provided, being disposed between any adjacent positive or negative electrode sheets by folding or winding.

In some embodiments, the electrode assembly may have a cylindrical shape, a flat shape, a polygonal column shape, or the like.

In some embodiments, the electrode assembly is provided with tabs that can conduct current away from the electrode assembly. The tab includes a positive tab and a negative tab.

In some embodiments, the battery cell may include a housing. The case is used to encapsulate the electrode assembly, the electrolyte, and the like. The shell can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), an aluminum-plastic film or the like.

As examples, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or other shaped battery cell, including a square-case battery cell, a blade-shaped battery cell, a polygonal-prismatic battery cell, such as a hexagonal-prismatic battery cell, or the like.

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.

In some embodiments, the battery may be a battery module, and when there are a plurality of battery cells, the plurality of battery cells are arranged and fixed to form one battery module.

In some embodiments, the battery may be a battery pack including a case and a battery cell, the battery cell or battery module being housed in the case.

In some embodiments, the tank may be part of the chassis structure of the vehicle. For example, a portion of the tank may become at least a portion of the floor of the vehicle, or a portion of the tank may become at least a portion of the cross member and the side member of the vehicle.

In some embodiments, the battery may be an energy storage device. The energy storage device comprises an energy storage container, an energy storage electric cabinet and the like.

In the field of batteries, an electrode assembly and an electrolyte are generally disposed in a battery cell, wherein the electrode assembly may include a stacked electrode sheet, a separator, etc., and one side end of the electrode sheet may be provided with a tab protruding to electrically connect the electrode assembly with an end cap, etc. In the process of manufacturing the electrode assembly, the electrode plate base body is generally manufactured first, and then the electrode plate base body is cut to form the electrode lug.

However, when the tab is cut, due to certain differences in parameters such as thickness, winding precision and the like of the pole piece, certain dislocation may exist between the position where the tab obtained by final cutting and the preset tab should be. When the electrode assembly is connected with the end cover assembly, dislocation of the electrode lug may cause interference between the electrode lug and parts such as plastic structures on the end cover, and meanwhile, welding area between the electrode lug and parts such as electrode terminals on the end cover is reduced, so that problems of reduced overcurrent area, reduced electrical connection stability and the like are caused, and the reliability of the electrode assembly is greatly influenced.

In some embodiments, devices such as a laser thickness measuring Device, a thickness control Device and a CCD (Charge-Coupled Device) camera Device are mutually matched, and the dislocation situation of the tab is corrected by detecting the thickness of the pole piece and setting a dislocation threshold value.

In view of this, the embodiment of the application provides a technical scheme, and it adopts and sets up cross cutting mechanism respectively in winding equipment's upper and lower stream to carry out processing to the mode that carries out the cross cutting twice to the pole piece in succession, can carry out accurate cutting to the utmost point ear again after the winding, thereby simply, effectively improve the position accuracy of utmost point ear, reduce the possibility that the utmost point ear misplaced.

Next, a manufacturing apparatus of an electrode assembly and a manufacturing method of an electrode assembly will be described with reference to fig. 1 to 7.

Referring to fig. 1, fig. 1 is a schematic structural view of an apparatus for manufacturing an electrode assembly according to an embodiment of the present application. In a first aspect, embodiments of the present application provide an apparatus 100 for manufacturing an electrode assembly, including a first die cutting mechanism 20, a winding mechanism 30, and a second die cutting mechanism 40, the first die cutting mechanism 20 being configured to die cut a plurality of preformed tabs 11 on a pole piece 10; a winding mechanism 30 is provided downstream of the first die cutting mechanism 20 for winding the pole piece 10 and the separator 13 and laminating the plurality of preformed tabs 11; a second die cutting mechanism 40 is disposed downstream of the winding mechanism 30, the second die cutting mechanism 40 being for die cutting the stacked plurality of preformed tabs 11 to form a plurality of tabs 12.

The present application provides a manufacturing apparatus 100 for manufacturing an electrode assembly, which includes a first die-cutting mechanism 20, a winding mechanism 30, and a second die-cutting mechanism 40 sequentially disposed along a processing sequence of a production line. In use of the manufacturing apparatus 100, the first die cutting mechanism 20 can first die cut the pole piece 10 to form a wide preformed tab 11 on a substrate according to a predetermined procedure.

Subsequently, the pole piece 10 is conveyed to a winding mechanism which is arranged at the downstream of the first die-cutting mechanism, and the cut pole piece 10 and the separator 13 can be wound to form a preset shape and size, and simultaneously, the preformed pole lugs 11 cut by the first die-cutting mechanism can be stacked in the thickness direction of the preformed pole lugs. Alternatively, two pole pieces 10 and at least one layer of separator 13 may be stacked and wound together at the same time, at which time the plurality of preformed tabs 11 on each pole piece 10 may be stacked by adjusting the winding size, while the preformed tabs 11 on different substrates are staggered from each other in the width direction, so as to achieve respective electrical connection.

After winding, the substrate formed by winding the pole piece 10 is conveyed to a second die cutting mechanism 40, and the second die cutting mechanism 40 can cut the preformed tab 11 which is stacked on the basis that the pole piece 10 is wound, and cut the wider preformed tab 11 into the tab 12 with the required and preset width so as to eliminate dislocation of the preformed tab 11 caused in the winding process.

The manufacturing equipment that this application provided has add second cross cutting mechanism 40 in the low reaches of winding mechanism 30 to make preformed tab 11 wider when first cross cutting, cut once more by second cross cutting mechanism 40 to the pole piece 10 after the coiling afterwards, can improve the position accuracy of tab 12 effectively through the cross cutting mode of first rough cut, second finish cut, reduce the influence of coiling dislocation to tab 12 position accuracy, thereby improve electrode assembly's reliability.

In some alternative embodiments, a winding mechanism 30 is used to wind the separator 13 and the two pole pieces 10; the manufacturing equipment comprises two first die cutting mechanisms 20, wherein the two first die cutting mechanisms 20 respectively die-cut the two pole pieces 10; the manufacturing apparatus includes two second die cutting mechanisms 40, the two second die cutting mechanisms 40 respectively die-cut the preformed tabs 11 of the two pole pieces 10.

According to the laminated structure in the electrode assembly, when the electrode sheet 10 is wound, the anode electrode sheet 10, the separator 13 and the cathode electrode sheet 10 may be sequentially laminated, and the first die-cutting mechanism 20 and the second die-cutting mechanism 40 may be respectively provided in two corresponding to the laminated structure and cut in one-to-one correspondence with the electrode sheet 10.

It will be appreciated that two pole pieces 10 in the same winding matrix may be made of different materials and die cut separately, i.e. two first die cutting mechanisms 20 may be provided separately and cut in one-to-one correspondence with the different pole pieces 10. Meanwhile, the second die-cutting mechanism 40 is used for cutting the matrix formed by jointly winding the two pole pieces 10, so that the two second die-cutting mechanisms 40 can be arranged at similar positions or in the same device to simultaneously cut the two preformed pole lugs 11 on the matrix, thereby improving the processing efficiency.

Referring to fig. 2 to 4 together, fig. 2 is a flowchart illustrating a method for manufacturing an electrode assembly according to an embodiment of the present disclosure, fig. 3 is a schematic structural diagram corresponding to step S1 shown in fig. 2, and fig. 4 is a schematic structural diagram corresponding to step S3 shown in fig. 2.

In a second aspect, the present application provides a method of manufacturing an electrode assembly, comprising:

s1, die-cutting a plurality of preformed lugs 11 on a pole piece 10;

s2, winding the pole piece 10 and the separator 13, and laminating a plurality of preformed pole lugs 11;

s3, die cutting the plurality of preformed tabs 11 stacked to form a plurality of tabs 12.

The present application also provides a method for manufacturing an electrode assembly, including providing a pole piece 10 and performing a first rough cutting step S1, specifically, first providing a pole piece 10, where the pole piece 10 may be rectangular and have a larger length, and may include a main body region and a tab region, where the two regions extend in the same direction and are arranged in parallel, and cutting the tab region into a plurality of preformed tabs 11 during cutting. Alternatively, the preformed tabs 11 may have the same or similar size and shape and be equally spaced in the direction of extension of the pole piece 10, and the preformed tabs 11 may have a wider size than the tabs 12 that the pole piece 10 should have in preparation for subsequent secondary cutting.

In step S2, the pole pieces 10 are wound, a corresponding number of pole pieces 10 are selected according to the structure of the electrode assembly, and a separator 13 may be disposed between two adjacent pole pieces 10. For example, two pole pieces 10 may be selected as the anode pole piece 10 and the cathode pole piece 10, and a separator is sandwiched between the two pole pieces 10, and the three are stacked and wound to form a winding matrix. In the winding matrix, a plurality of preformed tabs 11 located on the same pole piece 10 can be stacked by adjusting parameters such as winding parameters and intervals among the preformed tabs 11, that is, orthographic projections in the thickness direction of the tabs at least partially overlap each other. It will be appreciated that the preformed tabs 11 on different pole pieces 10 may be spaced apart in the width direction to reduce the likelihood of a current short circuit between the two.

In step S3, the winding substrate obtained by winding the tab 10 is cut for the second time, and the laminated preformed tab 11 is cut again into the desired tab 12, and the width and position of the tab 12 formed by this cutting should be the same as the final desired tab 12 width and position of the electrode assembly.

The electrode tab 12 dislocation brought by the winding process can be effectively trimmed by cutting through the die cutting before and after the winding step, so that the position and the dimensional accuracy of the electrode tab 12 are improved, and the reliability of the electrode assembly is further improved.

Referring to fig. 5, fig. 5 is a flowchart illustrating a method for manufacturing an electrode assembly according to another embodiment of the present application. In some alternative embodiments, step S1 of providing pole piece 10 is preceded by:

s01, acquiring the preset tab 12 width of the pole piece 10;

step S1 of providing the pole piece 10 further comprises:

s11, enabling the width of the preformed tab 11 to be larger than the width of the preset tab 12.

The manufacturing method may further include a step S01 of acquiring preset parameters before cutting the electrode tab 10, and specifically, the dimensional parameters of the electrode assembly may be designed according to the performance requirement of the electrode assembly and parameters of other components matched with the electrode assembly before manufacturing, where the parameters include the preset tab 12 width of the electrode tab 10, that is, the width of the tab 12 in the electrode assembly that is obtained by final processing. Alternatively, the tab 12 and the preformed tab 11 may be trapezoidal, and the preset dimensional parameters may include a top width, a bottom width, and the like, which may be selected according to the specific shape of the tab 12.

After the width of the preset tab 12 is obtained, the width of the preformed tab 11 formed by the first cutting can be designed according to the value of the width, so that the width of the preformed tab 11 is larger than the width of the preset tab 12, and therefore, the preformed tab 11 can have a certain space margin in the width direction for compatibility and elimination of dislocation caused by winding, and even if dislocation occurs between the preformed tabs 11 which are stacked, the overlapping area of each preformed tab 11 can cover the position where the tab 12 should be located, so that the position accuracy of the tab 12 is improved.

In some alternative embodiments, the width of the preset tab 12 is L1, the width of the preformed tab 11 is L2, and the step S1 of providing the pole piece 10 further includes:

1.2L1L 2 is less than or equal to 2L1.

On the basis that the width of the preformed tab 11 is larger than that of the preset tab 12, the preset tab 12 obtained according to design parameters is marked as L1, the width of the preformed tab 11 obtained by cutting is marked as L2, L2 can be enabled to be between 1.2L1 and 2L1, and corresponding adjustment can be carried out according to the size of dislocation space which possibly exists after winding. Setting the width of the preformed tab 11 within this range can provide the preformed tab 11 with a space margin for eliminating winding misalignment, while avoiding interference with winding of the pole piece 10 due to the excessively wide preformed tab 11.

In some alternative embodiments, between the step S2 of winding the pole piece 10 and the separator 13 and the step S3 of die cutting the plurality of preformed tabs 11 stacked and disposed further comprises:

s21, acquiring the width of a preset tab 12 of the pole piece 10 and the position of the preset tab 12;

s22, acquiring images of the preformed electrode lugs 11, and acquiring the overlapping width of the preformed electrode lugs 11 and the preset electrode lug positions;

s23, judging whether the preformed tab 11 is misplaced after winding according to the overlapping width and the width of the preset tab 12;

s24, recovering or rewinding the pole piece 10 comprising the preformed tab 11 with dislocation after winding.

After winding and before the second cutting, the winding substrate formed by winding can be further tested to determine whether the winding substrate can form the tab 12 conforming to the design parameters by the second cutting.

Specifically, the position of the preset tab 12 and the width of the preset tab 12 corresponding to the pole piece 10 may be obtained in step S21, and the obtaining manner is the same as that in the foregoing step S01, which is not described herein.

In steps S22 and S23, image acquisition is performed on the wound substrate obtained after winding is completed, specific positions of the preformed tabs 11 are obtained, the width of the overlapping area between the preformed tabs 11 is determined according to the positions and the positions of the preset tabs 12 in the step S21, and whether the tabs 12 with preset widths can be obtained through secondary die cutting is further determined according to the width of the overlapping area. If yes, a step S3 of the next die cutting can be performed; if the winding is impossible, it can be judged that the pole piece 10 to which the preformed tab 11 belongs is dislocated after winding, and correction is required.

It will be understood that the overlapping area between the position of the preformed tab 11 and the position of the preset tab 12 refers to the area where the preformed tab 11 is orthographically projected along the thickness direction thereof, and the orthographically projected area overlaps the preset design position of the tab 12 in the pole piece 10 assembly. In an embodiment in which the tab 12 has a shape having a top end and a bottom end with different widths, such as a trapezoid, when the width of the overlapping region is compared with the preset tab 12 width, a reference line may be made parallel to the extending direction of the pole piece 10, the reference line may be made to pass through the preformed tab 11, and the width of the overlapping region located on the same reference line is compared with the width of the preformed tab 11. Alternatively, the root of the preformed tab 11, i.e., the width of the side adjacent to the body of the pole piece 10, may be selected for comparison.

In step S24, the pole piece 10 determined to be misplaced after winding may be directly discarded and recycled, so as to reuse the electrode material, thereby reducing production cost; or, the pole piece 10 may be disassembled and rewound manually, and in this process, parameters of the winding mechanism may be adjusted according to the thickness of the pole piece 10 and the dislocation of the original preformed tab 11, so that the rewound preformed tab 11 conforms to the limitation on the position, that is, there is a sufficient overlapping area between each preformed tab 11 and the preset tab 12.

Alternatively, the steps S22 and S23 may be repeated after the re-winding, and a new winding base is re-inspected to further secure the positional accuracy of the tab 12 and the reliability of the electrode assembly.

In some optional embodiments, step S23 of determining whether the preformed tab is dislocated after winding according to the overlapping width and the preset tab width further includes:

s234, obtaining the maximum interval L5 between the positions of the pre-formed tabs staggered after winding and the preset tabs, and obtaining the number M of the pre-formed tabs in laminated arrangement;

s235, adjusting cutting positions in the step of die-cutting a plurality of preformed tabs on the pole piece, and enabling the cutting positions of the preformed tabs to move by L6 in the direction opposite to the dislocation direction, wherein L6=L5/(M-1).

In the embodiment of judging that the preformed tab 11 is dislocated after winding, the first die cutting parameters of other subsequent pole pieces 10 can be adjusted according to the specific dislocating condition of the preformed tab 11 so as to pre-correct the position of the preformed tab before winding.

Specifically, the specific position and width of the preformed tab 11 may be obtained according to the result of image acquisition in the foregoing step S22, so as to determine whether the preformed tab 11 is dislocated after winding, and for the preformed tab 11 with the dislocation after winding, the specific dislocation dimension L5 between the preformed tab 11 and the preset tab position may also be obtained according to the foregoing image acquisition result. It will be appreciated that the misalignment dimension may refer to the spacing between the central axis of the predetermined tab position and the central axis of the preformed tab 11.

Meanwhile, the winding times of the pole piece 10 can be obtained according to the winding parameters or the image acquisition results, namely, the specific number M of the preformed pole lugs 11 in each group of laminated preformed pole lugs 11 is obtained, and the position compensation parameter L6 can be calculated according to the dislocation distance L5 and the lamination number M.

Specifically, L6 may be L5/(M-1), and the misalignment size detected by the previous preformed tab 11 may be equally compensated for the position of each preformed tab 11 in each next pole piece 10. For example, if the wound pre-formed tab 11 is shifted to the edge position, the cutting position should be shifted to the opposite direction near the center by the compensation parameter L6, and vice versa.

By collecting the dislocation condition and the specific lamination number of the preformed tab 11 in the wound pole piece 10, the cutting parameters of the subsequent pole piece 10 can be corrected according to the data, so that the position of the preformed tab 11 is adjusted in advance in the step of the first die cutting, and the position accuracy of the tab 12 is further improved.

Referring to fig. 6, fig. 6 is a partial flowchart of a method for manufacturing an electrode assembly according to an embodiment of the present application. In some alternative embodiments, the step S23 of determining whether the pre-formed tab 11 is dislocated after winding according to the overlapping width and the preset tab 12 width, where the preset tab 12 has a width L1 and an overlapping width L3, further includes:

S231, judging whether the overlapping width accords with L3 or not more than 0.5L1, and if not, judging that the preformed tab 11 is misplaced after winding.

Specifically, the method for determining whether the preformed tab 11 has the dislocation after winding may be to compare the overlapping width obtained by the image acquisition with the width of the preset tab 12. The width of the preset tab 12 is denoted as L1, and the width of the overlapping area obtained after the image acquisition is denoted as L3, so that the width L3 of the tab 12 should be greater than or equal to 0.5L1, that is, the width of the overlap between the preformed tab 11 and the position of the preset tab 12 should be greater than or equal to half the width of the preset tab 12, so that the preformed tab 11 can be cut in the process of the second die cutting to obtain the tab 12 with sufficient width.

Alternatively, the misalignment may be determined by the overlapping area corresponding to the overlapping width, that is, the area of the area where the preformed tab 11 and the preset tab 12 overlap each other should be greater than or equal to one half the area of the preset tab 12.

The width value or the area value can accurately judge whether the preformed tab 11 is misplaced or not, and correct the preformed tab before performing the second die cutting in time, thereby further improving the reliability of the manufacturing method.

In some alternative embodiments, between the step S23 of judging whether the pre-formed tab 11 is misaligned after winding according to the overlapping width and the preset tab 12 width and the step S24 of recovering or re-winding the pole piece 10 including the pre-formed tab 11 misaligned after winding, the method further includes:

s232, obtaining the number N of the preformed tabs 11 which are arranged in a stacked mode and are staggered after winding;

s233, judging whether the number N accords with N less than or equal to 5, and if so, considering the preformed tab 11 which is stacked as not being misplaced after winding.

Alternatively, in an embodiment in which the occurrence of the misalignment after winding has been judged, further judgment may be made according to the number of the misaligned preformed tabs 11. Specifically, in step S22, image acquisition has been performed on the preformed tab 11, and further detection may be performed on the thickness distribution of the preformed tab 11 to assist in the determination. According to the position of the preformed tab 11 in the expectation and the thickness of each part of the preformed tab 11 after lamination, the position of each preformed tab 11 can be accurately obtained, whether each preformed tab 11 is misplaced after winding can be judged according to the position data, and the number of the preformed tabs 11 misplaced after winding can be obtained accordingly.

Further, the number of the preformed tabs 11 with the dislocation after winding is denoted as N, where the number N refers to the number of the preformed tabs 11 with the dislocation in the plurality of preformed tabs 11 protruding from the same pole piece 10 in the same tab 12 group stacked. The number of the laminated preformed tabs 11 is generally large, and in an embodiment in which there is a misalignment problem, but N is less than or equal to 5, the pole piece 10 may be regarded as not having a misalignment problem after winding, and the re-winding process may be omitted. The number of the tabs 12 which are dislocated, namely, the width of the tabs is possibly narrower after the second die cutting is smaller, so that the processing time can be saved and the processing efficiency can be improved under the condition of less influence on the connection of the tabs 12.

In some alternative embodiments, the step S22 of image capturing the preformed tab 11 includes:

and adopting a charge coupled device camera to acquire images.

In the step of collecting the image, a CCD (charge coupled device ) camera can be used as an image collecting module, the charge coupled device can change light rays into electric charges and store and transfer the electric charges, and the stored electric charges can be taken out to change the voltage, so that the CCD camera has the advantages of small volume, light weight, no influence of a magnetic field, clear imaging and the like, and has good vibration resistance and impact resistance.

Referring to fig. 7, fig. 7 is a partial flowchart of a method for manufacturing an electrode assembly according to another embodiment of the present application. In some alternative embodiments, step S3 of die cutting the plurality of preformed tabs 11 in a stacked arrangement further comprises:

s4, acquiring the width L1 of the preset tab 12 of the pole piece 10 and the position of the preset tab 12;

s5, trimming the tab 12 to enable the distance L4 between the edge of the tab 12 and the edge of the preset tab 12 in the width direction to be less than or equal to 0.25L1.

In order to further improve the position and dimensional accuracy of the tab 12, the tab 12 may be finished after the second die cut is completed. Specifically, the position of the preset tab 12 and the width of the preset tab 12 may be obtained first, and the obtaining methods of the two are the same as those in the foregoing embodiment, which is not described herein.

Subsequently, the tab 12 may be detected after the step S3 of the second die cutting, for example, the position of the tab 12 obtained by actually cutting may be obtained by detecting through an image acquisition manner, and the distance between the edge of the actual tab 12 and the edge of the preset tab 12 is denoted as L4, where L4 should be less than or equal to one fourth of the width L1 of the preset tab 12, so as to reduce the possibility that the tabs 12 interfere with each other or have too small welding area when connected with the structure such as the end cover assembly.

For example, the width of the tab 12 at the root may be 30mm to 40mm, that is, in the opposite side edges in the width direction, the allowable misalignment distance of each edge should be less than or equal to 10mm, in which range the process of trimming the tab 12 may be omitted, and the tab 12 may be regarded as not being misaligned, so as to improve the processing efficiency and reduce the processing cost.

In some alternative embodiments, step S1 of providing pole piece 10 includes:

s12, providing two pole pieces 10, and respectively cutting out a plurality of preformed pole lugs 11 on the two pole pieces 10;

the step S2 of winding the pole piece 10 and the separator 13 includes:

and S25, laminating the preformed tabs 11 of the two pole pieces 10.

Similarly to the aforementioned manufacturing apparatus, when the electrode assembly is manufactured, two electrode sheets 10 may be simultaneously provided and used as the anode electrode sheet 10 and the cathode electrode sheet 10, respectively, and in the step S1 of the first cutting, the preformed tab 11 may be formed by cutting on the two substrates, respectively, and the widths of the preformed tabs 11 on the two substrates may be the same or different according to the actual parameter difference of the electrode sheets 10, and the respective comparison manners are adopted in the aforementioned steps of comparing the widths.

In step S2 of winding the pole pieces 10, the two pole pieces 10 and the separator 13 may be alternately arranged one by one in the thickness direction, and then wound to form a desired winding base, and the tabs 12 of the two pole pieces 10 may be electrically connected to each other, and the separator 13 may serve as an insulating structure between the pole pieces 10. In the winding base, the preformed tabs 11 respectively located on the two pole pieces 10 may be respectively stacked independently of each other, respectively corresponding to the anode tab 12 group and the cathode tab 12 group, and the two tab 12 groups are close to respective preset positions and spaced apart from each other in the width direction.

In some alternative embodiments, step S3 of die cutting the plurality of preformed tabs 11 in a stacked arrangement further comprises:

s6, recovering the surplus materials of the pole piece 10 obtained by cutting in the step of providing the pole piece 10 and the step of die-cutting a plurality of preformed pole lugs 11 which are arranged in a laminated mode.

After the cutting is finished, the manufacturing method in the present application may further include a step of recovering the residual materials of the cutting, in which step S6, the residual materials between the tabs 12 cut from the substrate are recovered, and the residual materials may be reused by recasting into a foil or the like. The pole piece surplus materials obtained through recycling and cutting can save materials, reduce manufacturing cost, and reduce the influence of a processing method of secondary die cutting on the material consumption of the pole piece 10.

The application provides manufacturing equipment of an electrode assembly, which comprises two first die cutting mechanisms, a winding mechanism and two second die cutting mechanisms, wherein the first die cutting mechanisms are used for die cutting a plurality of preformed electrode lugs 11 on a pole piece 10; the winding mechanism is arranged at the downstream of the first die cutting mechanism and is used for winding the pole piece 10 and the separator 13 and laminating a plurality of preformed pole lugs 11; a second die cutting mechanism is disposed downstream of the winding mechanism for die cutting the stacked plurality of preformed tabs 11 to form a plurality of tabs 12.

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 apparatus for manufacturing an electrode assembly, comprising:

the first die cutting mechanism is used for die-cutting a plurality of preformed electrode lugs on the electrode plate;

the winding mechanism is arranged at the downstream of the first die cutting mechanism and is used for winding the pole piece and the separator and laminating the preformed pole lugs; and

the second die cutting mechanism is arranged at the downstream of the winding mechanism and is used for die cutting the plurality of preformed tabs which are stacked to form a plurality of tabs.

2. The manufacturing apparatus of claim 1, wherein the winding mechanism is for winding the separator and the two pole pieces;

the manufacturing equipment comprises two first die cutting mechanisms, wherein the two first die cutting mechanisms respectively die-cut the two pole pieces; the manufacturing equipment comprises two second die cutting mechanisms, wherein the two second die cutting mechanisms respectively die-cut the preformed electrode lugs of the two electrode plates.

3. A method of manufacturing an electrode assembly, comprising:

die-cutting a plurality of preformed lugs on the pole piece;

winding the pole piece and the separator, and laminating the plurality of preformed pole lugs;

And die cutting the laminated preformed tabs to form a plurality of tabs.

4. The method of manufacturing of claim 3, wherein the step of die cutting a plurality of preformed tabs on the pole piece is preceded by the step of:

acquiring a preset tab width of the pole piece;

the step of die cutting the plurality of preformed tabs on the pole piece further comprises:

and enabling the width of the preformed tab to be larger than the width of the preset tab.

5. The method of manufacturing of claim 4, wherein the predetermined tab width is L1 and the preformed tab width is L2, and the step of die cutting the plurality of preformed tabs on the pole piece further comprises:

1.2L1L 2 is less than or equal to 2L1.

6. The method of manufacturing of claim 3, wherein the step of winding the pole piece and separator and the step of die cutting the plurality of preformed tabs in a stacked arrangement further comprises:

acquiring a preset tab width and a preset tab position of the pole piece;

acquiring an image of the preformed tab to obtain the overlapping width of the preformed tab and the preset tab position;

judging whether the preformed tab is misplaced after winding according to the overlapping width and the preset tab width;

And (3) recovering or rewinding the pole piece comprising the preformed pole lug with dislocation after winding.

7. The method of manufacturing according to claim 6, wherein the step of judging whether the pre-formed tab is misaligned after winding according to the overlap width and the preset tab width further comprises:

obtaining the maximum interval L5 between the positions of the preformed lugs and the preset lugs, which are staggered after winding, and obtaining the number M of the preformed lugs which are stacked;

and adjusting cutting positions in the step of die-cutting a plurality of preformed tabs on the pole piece, so that the cutting positions of the preformed tabs are moved in a direction opposite to the dislocation direction by L6, and L6=L5/(M-1).

8. The method of manufacturing according to claim 6, wherein the predetermined tab width is L1 and the overlap width is L3, and the step of determining whether the preformed tab is misaligned after winding according to the overlap width and the predetermined tab width further comprises:

judging whether the overlapping width accords with L3 or not more than 0.5L1, and if not, judging that the preformed tab is misplaced after winding.

9. The method of manufacturing according to claim 6, wherein between the step of judging whether the pre-formed tab is misaligned after winding according to the overlap width and the preset tab width and the step of unwinding and rewound the pole piece of the pre-formed tab including the misalignment after winding, further comprises:

acquiring the number N of the preformed tabs which are arranged in a stacked manner and are staggered after winding;

judging whether the number N accords with N less than or equal to 5, and if so, regarding the preformed lugs which are arranged in a stacked mode as dislocation after winding does not occur.

10. The method of manufacturing of claim 6, wherein the step of image capturing the preformed tab comprises:

and adopting a charge coupled device camera to acquire images.

11. The method of manufacturing of claim 3, wherein the step of die cutting the plurality of preformed tabs in a stacked arrangement further comprises:

acquiring a preset tab width L1 of the pole piece and a preset tab position;

and trimming the tab to ensure that the distance L4 between the edge of the tab and the edge of the preset tab position in the width direction is less than or equal to 0.25L1.

12. A method of manufacturing as claimed in claim 3, wherein the step of die cutting a plurality of preformed tabs on the pole piece comprises:

providing two pole pieces, and respectively cutting out a plurality of preformed pole lugs on the two pole pieces;

the step of winding the pole piece and separator comprises:

and respectively laminating the preformed lugs of the two pole pieces.

13. The method of manufacturing of claim 3, wherein the step of die cutting the plurality of preformed tabs in a stacked arrangement further comprises:

and recycling the pole piece residual materials obtained by cutting in the step of die-cutting a plurality of preformed pole lugs on the pole piece and the step of die-cutting the plurality of preformed pole lugs which are arranged in a stacked manner.