CN116706259A

CN116706259A - Battery cell processing system and method, battery cell, battery and electric equipment

Info

Publication number: CN116706259A
Application number: CN202310936976.9A
Authority: CN
Inventors: 吴凯; 张彦超
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2023-07-28
Filing date: 2023-07-28
Publication date: 2023-09-05
Anticipated expiration: 2043-07-28
Also published as: CN116706259B

Abstract

The invention relates to the technical field of battery manufacturing, and particularly discloses a battery cell processing system and method, a battery cell, a battery and electric equipment, wherein the battery cell processing system comprises a conveying mechanism, bending rollers, a winding needle and a welding mechanism, the conveying mechanism comprises a plurality of conveying rollers, and the conveying rollers are arranged at intervals in a same direction in a rotating way so as to convey a positive plate and a negative plate; the bending rollers are arranged between any two adjacent conveying rollers to bend the positive lugs of the positive plate and bend the negative lugs of the negative plate; the winding needle is positioned at the downstream of the bending roller and is used for winding the bent positive plate and negative plate; the winding needle is arranged on one side of the winding needle so as to weld the wound positive electrode lug and the wound negative electrode lug. The technical scheme of the invention can simplify the processing procedure and improve the processing efficiency and the performance of the battery cell.

Description

Battery cell processing system and method, battery cell, battery and electric equipment

Technical Field

The invention relates to the technical field of battery manufacturing, in particular to a battery cell processing system and method, a battery cell, a battery and electric equipment.

Background

The cylindrical battery core ratio of the full tab to the cylindrical battery core of the traditional single tab has the following advantages: the charging is fast and the power is high; the structure is simple, so that the cost of the whole vehicle is reduced; the large-current charge and discharge has less heat productivity and longer service life. However, the integration and collection of the full tab is a difficulty in addition to the significant advantages.

In the existing winding method, the positive electrode sheet and the negative electrode sheet are generally required to be wound in a winding process, and then the positive electrode tab and the negative electrode tab are subjected to rubbing welding in a rubbing process, so that the process is complicated, metal particles are easy to appear in rubbing, and the internal structure of the battery cell is influenced.

Disclosure of Invention

The invention mainly aims to provide a battery cell processing system which aims at simplifying battery cell processing procedures and improving battery cell quality.

In order to achieve the above object, the present invention provides a system for processing a battery cell, comprising:

the conveying mechanism comprises a plurality of conveying rollers which are arranged at intervals in a same direction in a rotating way so as to convey the positive electrode plate and the negative electrode plate;

the bending rollers are arranged between any two adjacent conveying rollers to bend the positive lugs of the positive plate and bend the negative lugs of the negative plate;

The winding needle is positioned at the downstream of the bending roller and is used for winding the bent positive electrode sheet and negative electrode sheet; and

and the welding mechanism is arranged at one side of the winding needle so as to weld the wound positive electrode lug and the wound negative electrode lug.

In the battery cell processing process, the positive electrode plate and the negative electrode plate are conveyed by using conveying rollers, a plurality of conveying rollers are arranged at the position, the tension balance of the electrode plate can be kept by the conveying rollers, the flatness and the compactness of the surface of the electrode plate are improved, the electrode plate is prevented from loosening, and the stability and the accuracy of the winding quality are ensured. The bending roller is provided between the conveying rollers, and the bending roller may be provided between two conveying rollers upstream, downstream, or downstream of the conveyance, and is not limited herein. The bending roller can bend the edge of the pole piece while transmitting the pole piece, namely, after bending the positive lug, an included angle is formed between the positive lug and the positive plate body. The winding needle winds and forms the bent positive plate and the bent negative plate, so that the positive lug and the negative lug are wound and overlapped. And finally, welding the current collecting disc on the positive electrode lug and the negative electrode lug.

Therefore, in the battery cell processing system, the positive electrode lug of the positive electrode plate and the negative electrode lug of the negative electrode plate are directly bent through the arrangement of the bending roller in the battery cell conveying process; therefore, after the follow-up winding is completed, the process of rolling is not needed, the process can be saved, the particle interference caused by rolling to the inside of the battery cell can be reduced, and the quality of the battery cell is improved.

In an embodiment of the invention, the bending roller comprises a middle roller body and two bending parts arranged at two ends of the middle roller body, the diameter of each bending part is larger than that of the middle roller body, a bending surface is formed between each bending part and the middle roller body, and the bending surface is used for pressing the positive electrode lug and the negative electrode lug to bend.

Here, the bending roller comprises a bending part and a middle roller body, and a bending surface is formed at the joint of the bending part and the middle roller body through different diameters, so that the loss of the pole piece can be reduced, and the bending roller is convenient to process.

In an embodiment of the invention, the electrical core processing system further includes an indentation mechanism, wherein the indentation mechanism is disposed upstream of the bending roller, and the indentation mechanism is used for pressing the root of the positive tab and the root of the negative tab to form an indentation.

Here, the indentation mechanism forms the indentation at the bending position of the positive electrode lug and the negative electrode lug, so that the strength of the bending position is enhanced, and the positive electrode lug and the negative electrode lug can be bent more easily.

In an embodiment of the invention, the electrical core processing system further includes a punching mechanism, and the punching mechanism is disposed between the indentation mechanism and the bending roller, so as to form a perforation at the indentation of the positive electrode tab and the indentation of the negative electrode tab.

The root parts of the positive electrode lug and the negative electrode lug are perforated by the perforation mechanism, so that the bent positive electrode lug and negative electrode lug can be kept in a stable state, and the situation of tilting is avoided.

In an embodiment of the invention, the electrical core processing system further includes a slitting mechanism, where the slitting mechanism is disposed on one side of one of the conveying rollers and is located upstream of the bending roller, and is configured to slit the positive tab of the positive tab and the negative tab of the negative tab, so that the width of the positive tab and the width of the negative tab are in an increasing trend in a direction deviating from conveying.

Here, make the width of anodal ear and negative pole ear be the trend of increasing in the direction that deviates from the transport through cutting the mechanism, can make the utmost point ear width of electric core inner circle little, the utmost point ear width of outer lane is big, the utmost point ear of the inner circle of electric core after the coiling is unanimous with the thickness of outer utmost point ear to can improve the welding effect, and reduce the non-ferrous metal use amount of utmost point ear.

The invention also provides a battery cell processing method, which comprises the following steps:

conveying the positive plate and the negative plate respectively;

bending the positive lug of the conveyed positive plate and the negative lug of the negative plate to enable the positive lug and the positive plate body to be arranged at an included angle, and enabling the negative lug and the negative plate body to be arranged at an included angle;

And winding the positive plate, the negative plate and the diaphragm by using a winding needle to form a bare cell, and respectively welding the bent positive lug and negative lug.

According to the battery cell processing method, the positive electrode lug and the negative electrode lug are directly bent in the process of conveying the positive electrode plate and the negative electrode plate, so that welding can be directly performed after winding and forming, the rolling process is reduced, the processing efficiency is improved, the influence of particles generated by rolling on the battery cell can be reduced, and the quality of the battery cell is improved.

In an embodiment of the present invention, after the step of conveying the positive electrode sheet and the negative electrode sheet respectively, bending the positive electrode tab of the conveyed positive electrode sheet and the negative electrode tab of the conveyed negative electrode sheet so that the positive electrode tab and the positive electrode sheet form an included angle, and before the step of setting the negative electrode tab and the negative electrode sheet form an included angle, the method further includes:

and preprocessing the positive electrode lug of the conveyed positive electrode plate and the negative electrode lug of the negative electrode plate to form a pre-bending area parallel to the conveying direction.

Here, through carrying out preliminary treatment for anodal ear and negative pole ear department form the preflex region, can take place to bend more easily when bending the roller, thereby promote the effect of bending.

In an embodiment of the present invention, the step of pre-treating the positive tab of the positive electrode sheet and the negative tab of the negative electrode sheet to form a pre-bent area parallel to the conveying direction includes:

Prepressing the root of the positive electrode lug and the root of the negative electrode lug to form two indentations parallel to the conveying direction respectively;

and punching holes between the two indentations to form a plurality of holes which are arranged at intervals.

In this step, can promote the intensity of this department structure through pre-compaction indentation to cooperate with the perforation, make anodal ear and negative pole ear more take place to bend, and reduce the perk condition after bending, avoid the overlap joint probability of utmost point ear and aluminum hull, promote electric core performance.

In one embodiment of the present invention, a distance between two indentations is set as a; wherein a is more than 0 and less than or equal to 0.5mm.

Here, the distance between the two indentation that sets up not only can satisfy structural strength and easy bending effect, can reduce the material use of utmost point ear again.

In one embodiment of the present invention, the diameter of the through hole is set to b, wherein b is equal to or less than a.

Here, set up the diameter of perforation and be less than the distance between two indentation, convenient processing, and can promote the intensity of kink.

And cutting the conveyed positive plate and negative plate respectively, so that the widths of the positive lug at the edge of the positive plate and the negative lug at the edge of the negative plate are in an increasing trend in the direction deviating from conveying.

Here, cut positive plate and negative pole piece for positive tab and negative pole ear are less at the width of the inner circle of rolling up the core, and is great at the width of outer lane, thereby make positive tab and the negative pole ear after buckling the thickness of inner circle and outer lane the same, promote the welding effect.

In an embodiment of the present invention, the step of slitting the conveyed positive electrode sheet and negative electrode sheet respectively so that the widths of the positive electrode tab at the edge of the positive electrode sheet and the negative electrode tab at the edge of the negative electrode sheet are in an increasing trend in a direction away from the conveying direction includes:

and cutting the conveyed positive plate and negative plate respectively, so that the widths of the positive lug and the negative lug are linearly increased or stepwise increased in the direction deviating from the conveying direction.

Here, setting a linear increment or a stepwise increment can facilitate processing.

In an embodiment of the present invention, the diameter of the winding needle is set to L, the thickness of the positive electrode sheet is set to M1, the thickness of the negative electrode sheet is set to M2, and the winding number of the battery cell is set to N;

When the widths of the positive and negative lugs increase linearly in a direction away from the transport, the slope of the linear increase is k, wherein,；

or when the widths of the positive electrode lug and the negative electrode lug are in step increment in the direction deviating from conveying, the height difference of two adjacent steps is the sum of M1 and M2.

Here, when linearly increasing, the slope can make the widths of the positive electrode tab and the negative electrode tab satisfy the width increase required by the increase in the number of winding turns, and minimize the material use.

When the steps are gradually increased, the thickness consistency of the lugs of the inner ring and the outer ring can be improved by arranging the height difference of the two adjacent steps, and the use of materials is limited and reduced to the maximum extent.

In an embodiment of the present invention, bending the positive tab of the positive sheet and the negative tab of the negative sheet so that the positive tab and the positive sheet form an included angle, and the step of setting the negative tab and the negative sheet form an included angle includes:

and bending the positive lug of the conveyed positive plate and the negative lug of the negative plate to enable the positive lug to be perpendicular to the positive plate body, and enabling the negative lug to be perpendicular to the negative plate body.

Here, carry out perpendicular buckling with anodal ear and negative pole ear, can promote the compactness of utmost point ear, further make things convenient for subsequent welding.

In an embodiment of the present invention, the step of winding the positive electrode sheet, the negative electrode sheet and the separator to form a bare cell using a winding needle, and welding the bent positive electrode tab and the bent negative electrode tab includes:

respectively flattening the bent positive electrode lug and the bent negative electrode lug by using a pressing mechanism;

and welding the positive electrode lug and the negative electrode lug respectively by using a welding device.

Here, the pressure equipment mechanism can further promote the compactness of utmost point ear, reduces the space, further promotes the welding effect.

The invention also provides a battery cell, which is prepared by using any battery cell processing method.

The invention also provides a battery, which comprises the electric core.

The invention also provides electric equipment which comprises the battery or the battery core.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an embodiment of a cell processing system according to the present invention;

FIG. 2 is a schematic diagram of a bending roller in the cell processing system shown in FIG. 1;

FIG. 3 is a flow chart of an embodiment of a method for processing a battery cell according to the present invention;

fig. 4 is a schematic structural diagram of a bent positive plate prepared by the method for processing a battery cell shown in fig. 3;

fig. 5 is a schematic structural diagram of a bent negative electrode sheet prepared by the method for processing a battery cell shown in fig. 3;

fig. 6 is a schematic diagram of a portion of a battery cell manufactured by the battery cell processing method shown in fig. 3;

FIG. 7 is a flowchart of another embodiment of a method for processing a battery cell according to the present invention;

FIG. 8 is a flowchart of a method for processing a battery cell according to another embodiment of the present invention;

fig. 9 is a schematic structural diagram of a positive plate prepared by the method for processing a battery cell shown in fig. 7 and 8;

fig. 10 is a schematic structural diagram of a negative electrode sheet prepared by the cell processing method shown in fig. 7 and 8;

fig. 11 is an enlarged view at a in fig. 10.

Reference numerals illustrate:

reference numerals	Name of the name	Reference numerals	Name of the name
				100	Battery cell processing system	201	Positive tab
10	Conveying mechanism	2011	Indentation of
				11	Conveying roller	2012	Perforation
12	Bending roller	202	Positive plate
				121	Intermediate roller body	300	Negative plate
122	Bending part	301	Negative electrode ear
				123	Bending surface	302	Negative plate
200	Positive plate

The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that all directional indicators (such as up, down, left, right, front, and rear … …) in the embodiments of the present invention are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture (as shown in the drawings), and if the particular posture is changed, the directional indicator is changed accordingly.

In the present invention, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

Furthermore, the description of "first," "second," etc. in this disclosure is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" as it appears throughout is meant to include three side-by-side schemes, for example, "a and/or B", including a scheme, or B scheme, or a scheme that is satisfied by both a and B. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.

The batteries mentioned in the art can be classified into disposable batteries and rechargeable batteries according to whether they are rechargeable or not. The types of rechargeable batteries that are currently common are: lead acid batteries, nickel hydrogen batteries, and lithium ion batteries. The lithium ion battery is widely applied to pure electric vehicles and hybrid electric vehicles at present, and the capacity of the lithium ion battery used for the application is slightly lower, but the lithium ion battery has larger output and charging current, longer service life and higher cost.

The battery described in the embodiments of the present invention refers to a rechargeable battery. Hereinafter, the disclosed embodiments of the present invention will be mainly described by taking a lithium ion battery as an example. It should be appreciated that the disclosed embodiments are applicable to any other suitable type of rechargeable battery. The batteries according to the embodiments disclosed in the present invention may be directly or indirectly used in a suitable device to power the device.

Reference to a battery in the presently disclosed embodiments refers to a single physical module that includes one or more battery cells to provide a predetermined voltage and capacity. The battery cell is a basic unit in the battery, and comprises a positive pole piece, a negative pole piece, electrolyte and a separation film. The lithium ion battery cell mainly relies on movement of lithium ions between the positive electrode sheet and the negative electrode sheet. Generally, the packaging method can be divided into: cylindrical battery cells, cuboid battery cells and soft package battery cells. Hereinafter, it will be mainly spread around the cylindrical battery cell. It should be understood that the embodiments described hereinafter are also applicable in certain respects to a rectangular parallelepiped battery cell or a pouch battery cell.

The development of battery technology is to consider various design factors, such as energy density, cycle life, discharge capacity, charge-discharge rate, etc., and further consider the production cost and processing technology of the battery to improve the quality and production efficiency of the battery.

In the battery production and manufacturing process, the battery often needs to go through a plurality of working procedures and stations to finish production and measurement, and a complete battery is manufactured. Firstly, forming a positive pole piece, a negative pole piece, electrolyte and a separation film into a battery core shape, and then performing procedures such as shell entering, welding, formation and the like. For the full tab structure, after the positive plate, the negative plate and the diaphragm are wound and formed into the battery core, the positive tab and the negative tab are respectively positioned at two ends of the battery core, and are required to be collected and then welded to form a part for connecting the positive electrode and the negative electrode of the battery, and the welding quality of the battery tab directly influences the service life and the performance of the battery, so that the important research is required for collecting the positive tab and the negative tab and welding the positive tab and the negative tab.

In the related art, after the positive plate, the negative plate and the diaphragm are wound and formed by the battery cell processing system, the positive lug and the negative lug are flattened by the flattening mechanism, so that the positive plate, the negative plate and the diaphragm are positioned in the same plane, and the end cover is convenient to weld and cover. However, the process of rubbing needs to transfer the battery cell from one process to another process, the process is tedious, and the scraps of the positive electrode lug and the negative electrode lug easily appear in the rubbing process, and if the scraps enter the inside of the battery cell, the internal structure of the battery cell can be affected, and then the product yield can be affected.

Therefore, in order to solve the problems in the related art, the bending roller is added in the transmission mechanism, and the positive electrode lug and the negative electrode lug are directly bent in the process of transmitting the pole piece, so that welding can be performed without a rubbing process after winding, the processing process is simplified, and the problem of product yield caused by rubbing is reduced.

The battery cell processing system can be used for preparing the cylindrical battery cells and also can be used for preparing the cuboid battery cells.

Referring to fig. 1 and 2, in an embodiment, a system 100 for processing a battery cell according to the present invention includes a conveying mechanism 10, a bending roller 12, a winding needle and a welding mechanism, wherein the conveying mechanism 10 includes a plurality of conveying rollers 11, and the conveying rollers 11 are disposed at intervals and rotate in the same direction to convey a positive electrode sheet 200 and a negative electrode sheet 300;

the bending roller 12 is disposed between any two adjacent conveying rollers 11 to bend the positive tab 201 of the positive tab 200 and bend the negative tab 301 of the negative tab 300;

the winding needle is positioned at the downstream of the bending roller 12 and is used for winding the bent positive electrode sheet 200 and negative electrode sheet 300; is provided at one side of the winding needle to weld the wound positive electrode tab 201 and negative electrode tab 301.

The positive electrode sheet 200 and the negative electrode sheet 300 may have a structure in which a current collector is coated with a corresponding positive electrode coating and negative electrode coating, that is, the positive electrode sheet 200 is coated with the positive electrode coating in a coating region in the middle of the current collector, and the material of the positive electrode coating is not limited and may be reasonably selected. And the portion of the current collector where the positive electrode coating is not applied is the positive electrode tab 201. Similarly, the negative electrode sheet 300 is formed by coating a negative electrode coating on a coating region of a current collector, and the edge of the current collector is a negative electrode tab 301.

The positive electrode sheet 200 and the negative electrode sheet 300 are wound bodies, and when processing is performed, the wound bodies of the electrode sheet and the separator are transported separately and transported together to a winding needle for winding and forming. The conveying mechanism 10 is a component between the winding body and the winding needle, namely comprises a plurality of conveying rollers 11 arranged at intervals, the conveying rollers 11 can keep tension balance of the pole piece, flatness and compactness of the surface of the pole piece are improved, the pole piece is prevented from loosening, and stability and accuracy of winding quality are guaranteed. The conveying roller 11 can be cylindrical in shape and is rotatably connected to a frame body, so that the conveying roller can rotate along the conveying direction while supporting the pole piece and the diaphragm, and damage and resistance to the pole piece and the diaphragm are reduced. In other examples, the conveying roller 11 may be a shuttle or dumbbell, and is not limited herein. The material of the conveying roller 11 may be metal, wood or rubber, or when the material of the conveying roller 11 is metal, an elastic layer, such as a rubber layer, may be disposed on the surface of the conveying roller, so as to improve the protection effect and the tension effect on the pole piece.

The bending roller 12 is disposed between the two conveying rollers 11, and the bending roller 12 may be disposed between the two conveying rollers 11 upstream, downstream, or in the middle of conveying, and is not limited herein. It will be appreciated that, in order to bend the positive electrode sheet 200 and the negative electrode sheet 300 at the same time, two bending rollers 12 are provided, one bending roller 12 is disposed between two conveying rollers 11 for conveying the positive electrode sheet 200, and the other bending roller 12 is disposed between two conveying rollers 11 for conveying the negative electrode sheet 300, so that the positive electrode tab 201 and the negative electrode tab 301 can be bent while the positive electrode sheet 200 and the negative electrode sheet 300 are conveyed, that is, an included angle is formed between the positive electrode tab 201 and the positive electrode sheet 202 after bending, an included angle is formed between the negative electrode tab 301 and the negative electrode sheet 302 after bending, and the positive electrode sheet 202 (the negative electrode sheet 302) is in a structure after the current collector is coated with a coating. The material of the bending roller 12 may be the same as or different from the material of the conveying roller 11, and is not limited herein.

The winding needle is positioned downstream of the bending roller 12 and the conveying roller 11, and winds and forms the bent positive electrode sheet 200 and negative electrode sheet 300, so that the positive electrode tab 201 and the negative electrode tab 301 are wound and overlapped. The structure of the winding needle can be reasonably selected, and the structure of the winding needle is not improved. After the winding formation is completed, the battery cell may be removed from the winding needle, placed on a welding mechanism, and the current collecting plate may be welded to the positive electrode tab 201 and the negative electrode tab 301. The welding means here may be laser welding.

Therefore, in the battery cell processing system 100 of the present invention, the positive tab 201 of the positive electrode sheet 200 and the negative tab 301 of the negative electrode sheet 300 are directly bent by the arrangement of the bending roller 12 during the battery cell conveying process; therefore, after the follow-up winding is completed, the process of rolling is not needed, the process can be saved, the particle interference caused by rolling to the inside of the battery cell can be reduced, and the quality of the battery cell is improved.

Referring to fig. 2, in an embodiment of the invention, the bending roller 12 includes a middle roller body 121 and two bending portions 122 disposed at two ends of the middle roller body 121, the diameter of the bending portions 122 is greater than that of the middle roller body 121, a bending surface 123 is formed between the bending portions 122 and the middle roller body 121, and the bending surface 123 is used for pressing the positive tab 201 and the negative tab 301 to bend.

Here, the bending roller 12 includes a bending portion 122 and an intermediate roller body 121, the cross-sectional shape of the intermediate roller body 121 is circular, and is used for supporting the coating areas of the positive electrode tab 200 and the negative electrode tab 300, and the cross-sectional shape of the bending portion 122 is circular, and the diameter is larger than that of the intermediate roller body 121, and corresponds to the edge positions of the positive electrode tab 200 and the negative electrode tab 300, that is, the positive electrode tab 201 and the negative electrode tab 301. When the positive electrode sheet 200 passes through the bending roller 12, the positive electrode tab 201 and the negative electrode tab 301 are bent by the bending surface 123 between the positive electrode tab and the negative electrode tab due to the blocking of the bending portion 122, and are disposed at an angle to the positive electrode sheet 202 (negative electrode sheet 302).

The bending roller 12 formed by two cylinders with different diameters can improve structural stability, and the bending part 122 and the middle roller body 121 are of an integrated structure, so that the bending roller 12 is convenient to process, and the smooth surface can reduce the loss to pole pieces. Meanwhile, the two bending parts 122 can correct the positions of the positive electrode plate 200 and the negative electrode plate 300 perpendicular to the conveying direction, so that the conveying stability of the electrode plates is improved. In other examples, the bending roller 12 may be two plate structures disposed at an angle.

Referring to fig. 9 to 11, in an embodiment of the invention, the electrical core processing system 100 further includes an indentation mechanism, which is disposed upstream of the bending roller 12, and is configured to press down on the root of the positive tab 201 and the root of the negative tab 301 to form an indentation 2011.

Here, the specific structure of the indentation mechanism is not limited, and in an example, the indentation mechanism may be a pressing blade driven by a driving member, and the root portions of the positive electrode tab 201 and the negative electrode tab 301 are pressed in the vertical direction, so that the indentation 2011 is formed. In another example, the indentation mechanism may also be a fine roller that rolls from the root positions of the positive tab 201 and the negative tab 301 to form the indentations 2011. Alternatively, in other examples, the indentation mechanism may be a clamping member, and the indentation 2011 is formed by clamping the root portions of the positive tab 201 and the negative tab 301. The creasing mechanism is arranged upstream of the creasing roller 12, i.e. creasing is performed after passing the creasing mechanism, so that the creasing mechanism may be arranged after transportation of the roll or may be formed during coating, without limitation.

The indentation mechanism can be carried out during the conveying process or before the conveying process. The indentation 2011 is formed at the bending position of the positive electrode lug 201 and the negative electrode lug 301 through the indentation mechanism, so that the strength of the bending position of the positive electrode lug 201 and the negative electrode lug 301 is enhanced, the positive electrode lug 201 and the negative electrode lug 301 can be bent more easily, and the bending efficiency and the bending effect are improved.

With continued reference to fig. 11, in an embodiment of the present invention, the electrical core processing system 100 further includes a punching mechanism, which is disposed between the indentation mechanism and the bending roller 12, so as to form a perforation 2012 at the indentation 2011 of the positive tab 201 and at the indentation 2011 of the negative tab 301.

In one example, the punching mechanism may be a laser device that performs punching by a laser. In another example, the punching mechanism may also be a mechanical punching device, such as a punching needle, that performs punching at the positions of the positive electrode tab 201 and the negative electrode tab 301 by moving up and down, forming the punched holes 2012. The punching mechanism is arranged at the downstream of the indentation mechanism to perform positioning punching according to the position of the indentation 2011 so as to improve the consistency of the position of the perforation 2012. Meanwhile, the punching mechanism is arranged at the upstream of the bending roller 12, and the pre-bending area is formed by the arrangement of the punching 2012 and the indentation 2011, so that the bending roller 12 can bend the positive electrode lug 201 and the negative electrode lug 301 more conveniently, and a better bending effect is formed.

The root parts of the positive electrode lug 201 and the negative electrode lug 301 are perforated by the perforation mechanism, so that the bent positive electrode lug 201 and the bent negative electrode lug 301 can keep a stable bending state, the situation of tilting is avoided, and the performance of the battery cell is improved.

Referring to fig. 9 and 10, in an embodiment of the invention, the electrical core processing system 100 further includes a slitting mechanism, which is disposed on one side of one of the conveying rollers 11 and is located upstream of the bending roller 12, and is configured to slit the positive tab 201 of the positive tab 200 and the negative tab 301 of the negative tab 300, so that the width of the positive tab 201 and the width of the negative tab 301 are in an increasing trend in a direction away from the conveying direction.

Here, the slitting mechanism may be a driving member for driving a cutter, scissors, or laser, and is not limited thereto, and may be capable of cutting or shearing the positive tab 201 and the negative tab 301. The slitting structure is provided on one side of one conveying roller 11, that is, on the same horizontal plane as the conveying roller 11, or on the side above or below the conveying roller 11 in the vertical direction, which is not limited herein. The slitting mechanism is provided upstream of the bending roller 12, and bends after cutting the positive tab 201 and the negative tab 301. In one example, if the cell processing system 100 further includes an indentation mechanism, the slitting mechanism may be located upstream of the indentation mechanism or downstream of the indentation mechanism. Alternatively, the slitting device may further include a punching mechanism, which may be located upstream or downstream of the punching mechanism, and is not limited herein.

The widths of the positive electrode tab 201 and the negative electrode tab 301 are gradually increased in a direction away from the conveying direction, and the increase may be gradually increased or stepwise increased, which is not limited herein. The width of the positive tab 201 and the width of the negative tab 301 are gradually increased in the direction away from the conveying direction, that is, the width of the positive tab 201 and the width of the negative tab 301 are gradually reduced in the conveying direction, that is, the width of the tab wound first is smaller, the width of the tab of the inner ring of the battery cell is small, and along with the increase of the diameter of the battery cell, the width of the positive tab 201 and the width of the negative tab 301 are also increased, that is, the width of the tab of the outer ring is increased, so that the end part from the bent tab to the center of the battery cell is consistent, and the thickness of the inner ring and the thickness of the outer ring of the battery cell are consistent.

The width of the positive electrode lug 201 and the width of the negative electrode lug 301 are gradually increased in the direction deviating from conveying through the slitting mechanism, the width of the electrode lug of the inner ring of the battery cell can be small, the width of the electrode lug of the outer ring of the battery cell is large, and the thickness of the electrode lug of the inner ring of the battery cell after winding is consistent with that of the outer layer of the electrode lug, so that convenience in collecting the electrode lug is improved, the welding effect can be improved, the use amount of nonferrous metals of the electrode lug is reduced, and the cost is reduced.

Referring to fig. 3 to 5, the present invention further provides a method for processing a battery cell, where the method includes:

Step S1: conveying the positive electrode sheet 200 and the negative electrode sheet 300, respectively;

step S2: bending the positive electrode lug 201 of the conveyed positive electrode plate 200 and the negative electrode lug 301 of the negative electrode plate 300 so that the positive electrode lug 201 and the positive electrode plate 202 form an included angle, and the negative electrode lug 301 and the negative electrode plate 302 form an included angle;

step S3: the positive electrode sheet 200, the negative electrode sheet 300 and the separator are wound by using a winding needle to form a bare cell, and the bent positive electrode tab 201 and the bent negative electrode tab 301 are welded respectively.

In step S1, the positive electrode sheet 200 and the negative electrode sheet 300 are conveyed by the conveying mechanism 10, respectively, and the conveying mechanism 10 includes a plurality of conveying rollers 11 and can be driven to rotate by the winding driving force of the winding needle to drive the positive electrode sheet 200 and the negative electrode sheet 300 to be conveyed forward. Here, the membrane is also required to be simultaneously delivered, which is not described in detail herein. The bending of the positive tab 201 and the negative tab 301 in step S2 is achieved by the bending roller 12 disposed in the conveying process, the bending roller 12 is located between any two conveying rollers 11, and the tab is directly bent in the conveying process. The bending angle may be 60 ° to 95 °, and is not particularly limited. The bending treatment is directly carried out in the conveying process, so that the rolling process after winding can be canceled, the one-step in-place process is realized, and the processing process is simplified; and can reduce the metal scraps generated by rubbing and leveling, and improve the performance of the battery cell. In step S3, the winding needle winds the positive electrode sheet 200, the separator, the negative electrode sheet 300 and the separator into a bare cell, at this time, the positive electrode tab 201 and the negative electrode tab 301 are also in a winding and overlapping state, and the tab in the processing mode can be directly spot-welded or compacted and then welded, so that the welding effect can be effectively improved.

The battery cell processing method directly bends the positive electrode lug 201 and the negative electrode lug 301 in the process of conveying the positive electrode plate 200 and the negative electrode plate 300, so that the battery cells can be directly welded after winding and forming, the rolling process is reduced, the processing efficiency is improved, the influence of particles generated by rolling on the battery cells can be reduced, and the quality of the battery cells is improved.

Referring to fig. 7, in an embodiment of the present invention, after step S1 of conveying the positive electrode sheet 200 and the negative electrode sheet 300 respectively, bending the positive electrode tab 201 of the conveyed positive electrode sheet 200 and the negative electrode tab 301 of the conveyed negative electrode sheet 300 so that the positive electrode tab 201 and the positive electrode sheet 202 form an included angle, and before step S2 of setting the negative electrode tab 301 and the negative electrode sheet 302 form an included angle, the method includes:

step S201: the positive tab 201 of the positive tab 200 and the negative tab 301 of the negative tab 300 are pre-processed to form a pre-bent region parallel to the conveying direction.

In order to bend the positive tab 201 and the negative tab 301 more easily, before bending, in the step S201, the root portions of the positive tab 201 and the negative tab 301 are pretreated, where the pretreatment may be to set folds, and the corresponding pre-bending area is the indentation 2011; or punching, wherein the pre-bending area is a plurality of holes which are correspondingly distributed at intervals; or thinning, wherein the pre-bending area is a thinner area; or the binding line is arranged, so that the positive tab 201 and the negative tab 301 are easier to bend along the pre-bending area when passing through the bending roller 12, and the bending yield is improved. Therefore, the root portions of the positive electrode tab 201 and the negative electrode tab 301 form a pre-bent region, and bending can be more easily performed when passing through the bending roller 12, thereby improving the bending effect and preventing the occurrence of warpage.

In an embodiment of the present invention, the step of pre-treating the positive tab 201 of the positive electrode tab 200 and the negative tab 301 of the negative electrode tab 300 to form a pre-bent area parallel to the conveying direction includes:

step S2011: prepressing the root of the positive tab 201 and the root of the negative tab 301 to form two indentations 2011 parallel to the conveying direction;

step S2012: punching is performed between two indentations 2011 to form a plurality of spaced perforations 2012.

In the step S2011, the root portions of the positive electrode tab 201 and the negative electrode tab 301 are pre-pressed, that is, the root portions are pressed by the indentation mechanism, which may be a linear pressing knife, so as to form a linear indentation 2011, and two linear indentations 2011 are provided here, so that punching between the two parts is facilitated. The form of the linear indentation 2011 is not limited, and may be a continuous linear type or a discontinuous broken line type. In step S2012, the hole is punched between the two indentations 2011, and may be punched by a laser punching process or a mechanical punching process 2012, which is not limited herein, to form a plurality of holes 2012, and the holes are arranged at intervals in the length direction of the pole piece. The dimensions of the perforations 2012 and the indentations 2011 are not limited. In other examples, the indentation mechanism may be a plate-type pressing tool, so as to directly form an indentation 2011 with a width, and perform punching on the indentation 2011. The opening shape of the perforation 2012 is not limited, and may be circular, diamond-shaped, or elliptical.

The strength of the structure can be improved through the prepressing indentation 2011 and matched with the perforation 2012, so that the pre-bending area of the positive electrode lug 201 and the negative electrode lug 301 is easier to bend, the tilting condition after bending is reduced, the overlapping probability of the electrode lug and the aluminum shell is avoided, and the performance of the battery cell is improved.

Referring to fig. 11, in an embodiment of the present invention, a distance between two indentations 2011 is set as a; wherein a is more than 0 and less than or equal to 0.5mm.

Here, when the two indentations 2011 are linear indentations 2011, the distance between the two indentations 2011 is preferably designed to be smaller so as to facilitate bending, so that the distance between the two indentations 2011 is designed to be a,0 < a is less than or equal to 0.5mm, for example, a may be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc.

The distance between the two indentations 2011 can satisfy the structural reinforcement of the root portions of the positive electrode tab 201 and the negative electrode tab 301, and the bending is easy, and the material use of the tab can be further reduced.

With continued reference to fig. 11, in an embodiment of the present invention, the diameter of the through hole 2012 is set to b, where b is less than or equal to a.

Here, the perforation 2012 is circular, the diameter of the perforation 2012 is smaller than the width of the indentations 2011, that is, the perforation 2012 is located between the two indentations 2011 and is not in contact with the indentations 2011, when the positive tab 201 and the negative tab 301 are bent, the radial line of the perforation 2012 can be a folding line for bending, so that bending is easier, the intensity of the bending position of the indentations 2011 can be improved, and the service performance of the battery cell is improved. In other examples, when the indentation 2011 is of a dashed line type, the diameter of the perforation 2012 may be larger than a, such that a perforation 2012 is located between two intermittent lines of the indentation 2011.

Further, depending on the diameter of the perforations 2012, the number of perforations 2012 may be set as desired, i.e., the distance between two perforations 2012 is c, which may be greater than b or less than b. When the cell size is large, the distance between two perforations 2012 may be smaller than the diameter when the diameter of the corresponding perforation 2012 is relatively large; where the diameter of the perforations 2012 is relatively small, the distance between the diameters of the two perforations 2012 may be greater than the diameter of the perforations 2012.

Referring to fig. 6, 8 and 9, in an embodiment of the invention, after step S1 of conveying the positive electrode sheet 200 and the negative electrode sheet 300 respectively, the positive electrode tab 201 of the conveyed positive electrode sheet 200 and the negative electrode tab 301 of the conveyed negative electrode sheet 300 are bent so that the positive electrode tab 201 and the positive electrode sheet 202 form an included angle, and before step S2 of setting the negative electrode tab 301 and the negative electrode sheet 302 form an included angle, the method further includes:

step S202: the conveyed positive electrode plate 200 and the conveyed negative electrode plate 300 are respectively cut, so that the widths of the positive electrode lug 201 at the edge of the positive electrode plate 200 and the negative electrode lug 301 at the edge of the negative electrode plate 300 are in an increasing trend in the direction deviating from conveying.

The slitting of the positive electrode tab 200 and the negative electrode tab 300 refers to a cutting process of edges of the positive electrode tab 201 and the negative electrode tab 301 by a slitting mechanism, and the slitting process may be performed during the conveying process of the positive electrode tab 200 and the negative electrode tab 300, so that the widths of the positive electrode tab 201 and the negative electrode tab 301 may be gradually increased in a direction deviating from the conveying direction, for example, may be gradually increased, or may be gradually increased in a step-like manner, which is not limited herein. When the positive electrode sheet 200 and the negative electrode sheet 300 need to undergo a pretreatment process during the processing of the battery cell, the slitting process may be located before the pretreatment or after the pretreatment step, which is not limited herein.

The slitting treatment can enable the width of the positive electrode lug 201 and the negative electrode lug 301 at the inner ring of the winding core to be smaller and the width of the outer ring to be larger, so that the thicknesses of the bent positive electrode lug 201 and the bent negative electrode lug 301 at the inner ring and the outer ring are the same, and the welding effect is improved.

In an embodiment of the present invention, the positive electrode tab 200 and the negative electrode tab 300 are respectively cut so that the widths of the positive electrode tab 201 at the edge of the positive electrode tab 200 and the negative electrode tab 301 at the edge of the negative electrode tab 300 are in an increasing trend in the direction away from the conveying direction, which includes:

step S2021: the positive electrode tab 200 and the negative electrode tab 300 are respectively slit, so that the widths of the positive electrode tab 201 and the negative electrode tab 301 are linearly increased or stepwise increased in a direction away from the conveyance direction.

Here, when laser cutting is used, the edge positions of the positive tab 201 and the negative tab 301 can be cut by setting the scanning path of the laser to linearly increment, and the widths of both are linearly increment in the direction away from the conveyance. Or, the scanning path of the laser is set to be in a stepwise increasing structure, so that the edges of the positive electrode tab 201 and the negative electrode tab 301 are also in a stepwise increasing structure. The linear increment growth mode and the step increment growth mode can facilitate processing and improve processing efficiency.

In an embodiment of the present invention, the diameter of the winding needle is set to L, the thickness of the positive electrode sheet 200 is set to M1, the thickness of the negative electrode sheet 300 is set to M2, and the winding number of the battery cell is set to N;

when the widths of the positive tab 201 and the negative tab 301 are linearly increased in a direction away from the conveyance, the slope of the linear increase is k, wherein,；

or, when the widths of the positive tab 201 and the negative tab 301 are stepwise increased in the direction away from the conveying direction, the height difference between two adjacent steps is the sum of M1 and M2.

Here, the diameter of the winding needle is L, and according to the thickness of the positive electrode sheet 200 and the thickness of the negative electrode sheet 300, and the winding number of turns of the battery core, the total length of the wound electrode sheet of the battery core is pi [ l+2n (m1+m2) ], when the widths of the positive electrode tab 201 and the negative electrode tab 301 linearly increase in the direction away from the conveying direction, in order to improve the consistency of the end portions of the positive electrode tab 201 and the negative electrode tab 301 of the wound battery core in the middle of the battery core, the tab of the next turn covers at least the tab of the previous turn, so the height difference of the oblique edges of the adjacent two turns of the positive electrode tab 201 and the negative electrode tab 301 is m1+m2, and thus, the slope k of the linear increase at least satisfies the above formula, and the slope can make the widths of the positive electrode tab 201 and the negative electrode tab 301 satisfy the width increase required by the increasing number of turns, and minimize the material use.

Similarly, when the widths of the positive electrode tab 201 and the negative electrode tab 301 are stepwise increased in the direction away from the conveyance, the length of each step is set to gradually increase with the number of winding turns, thereby satisfying the length of one winding turn. The height difference between the adjacent steps compensates for the increased thickness value of the wound positive and negative electrode sheets 200 and 300, so that the thickness consistency of the tabs of the inner and outer rings can be improved, and the use of materials can be maximally limited and reduced.

In an embodiment of the present invention, bending the positive tab 201 of the conveyed positive electrode sheet 200 and the negative tab 301 of the negative electrode sheet 300 so that the positive tab 201 and the positive sheet 202 form an included angle, and the step S2 of setting the negative tab 301 and the negative sheet 302 form an included angle includes:

step S21: the positive tab 201 of the positive electrode sheet 200 and the negative tab 301 of the negative electrode sheet 300 are bent so that the positive tab 201 is perpendicular to the positive sheet 202, and the negative tab 301 and the negative sheet 302 are perpendicular to each other.

Here, the included angle of the two included angle-forming portions of the bending roller 12 is set to 90 °, so that the positive electrode lug 201 and the negative electrode lug 301 are perpendicularly bent, and the perpendicularly bent positive electrode lug 201 and negative electrode lug 301 can be parallel to the end face of the battery cell, so that the tightness of the electrode lug can be improved, and further subsequent welding is facilitated.

In an embodiment of the present invention, the step S3 of winding the positive electrode tab 200, the negative electrode tab 300 and the separator to form a bare cell by using a winding needle, and welding the bent positive electrode tab 201 and the bent negative electrode tab 301 respectively includes:

step S31: flattening the bent positive electrode lug 201 and the bent negative electrode lug 301 by using a pressing mechanism;

step S32: the positive electrode tab 201 and the negative electrode tab 301 are welded, respectively, using a welding device.

Here, the press-fitting mechanism and the welding device may be of an integral structure or a separate structure, and are not limited thereto. After the positive electrode tab 201 and the negative electrode tab 301 are bent and wound, an avoidance space is formed on the end face of the battery cell, so that welding is facilitated. In the method, the press-fitting mechanism and the welding device can be of an integral structure, the positive electrode lug 201 and the negative electrode lug 301 are directly pressed by driving the press-fitting mechanism, avoiding the avoidance space, and being capable of pressing out air between the electrode lugs, further improving the compactness of the electrode lugs and reducing the gap; and meanwhile, the welding device is used for welding the avoidance space, so that the probability of false welding is reduced, and the welding effect is further improved.

Referring to fig. 6, the present invention further provides a battery cell manufactured by using any one of the above battery cell manufacturing methods, and because the manufacturing method of the battery cell is any one of the above battery cell manufacturing methods, all the technical solutions of all the above embodiments are adopted, and therefore, the battery cell has at least all the beneficial effects brought by the technical solutions of the above embodiments, which are not repeated herein.

The positive electrode lug 201 and the negative electrode lug 301 of the battery cell can reduce the probability of warping through bending and pretreatment of the bending roller 12, so that the contact with an aluminum shell is reduced, and the service performance of the battery cell is improved. Meanwhile, after the positive lug and the negative lug of the battery cell are cut, the thickness of the lug of the inner ring and the thickness of the lug of the outer ring are consistent, the cold joint is reduced, and the welding effect is improved.

The application also provides a battery, the battery comprises the battery core, and the preparation method of the battery core adopts all the technical schemes of all the embodiments, so that the battery has at least all the beneficial effects brought by the technical schemes of the embodiments, and the description is omitted. The battery can be a lithium ion battery, a sodium ion battery, a potassium ion battery, an air battery and the like, and the specific type of the battery is not limited in the application. Further, the battery may be a battery module or a battery pack, or the like.

The application also provides electric equipment which comprises the battery or the battery core. The specific structure of the battery core and the battery refers to the above embodiments, and because the electric equipment adopts all the technical schemes of all the embodiments, the electric equipment at least has all the beneficial effects brought by the technical schemes of the embodiments, and the details are not repeated here.

The electric equipment can be a mobile phone, a notebook computer, a battery car, an electric car, an energy storage station and the like, and the specific type of the electric equipment is not limited. When the electric equipment comprises a battery monomer, the power supply can be improved through the battery monomer. When the powered device includes a battery, the power may be provided by the battery.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the scope of the application, and all equivalent structural changes made by the description of the present application and the accompanying drawings or direct/indirect application in other related technical fields are included in the scope of the application.

Claims

1. A cell processing system, the cell processing system comprising:

2. The battery cell processing system of claim 1, wherein the bending roller comprises a middle roller body and two bending parts arranged at two ends of the middle roller body, the diameter of each bending part is larger than that of the middle roller body, a bending surface is formed between each bending part and the middle roller body, and the bending surface is used for pressing the positive electrode lug and the negative electrode lug for bending.

3. The cell processing system of claim 1, further comprising an indentation mechanism disposed upstream of the bending roller for pressing down on the root of the positive tab and the root of the negative tab to form an indentation.

4. The cell processing system of claim 3, further comprising a punch mechanism disposed between the indentation mechanism and the bending roller to form perforations at the indentations of the positive tab and the negative tab.

5. The cell processing system according to any one of claims 1 to 4, further comprising a slitting mechanism disposed on one side of one of the conveying rollers and upstream of the bending roller for slitting the positive tab of the positive tab and the negative tab of the negative tab so that the widths of the positive tab and the negative tab have an increasing tendency in a direction away from the conveyance.

6. The battery cell processing method is characterized by comprising the following steps of:

conveying the positive plate and the negative plate respectively;

7. The method for processing a battery cell according to claim 6, wherein after the step of conveying the positive electrode sheet and the negative electrode sheet respectively, bending the positive electrode tab of the conveyed positive electrode sheet and the negative electrode tab of the conveyed negative electrode sheet so that the positive electrode tab and the positive electrode sheet form an included angle, and before the step of setting the negative electrode tab and the negative electrode sheet form an included angle, further comprising:

8. The method of processing a battery cell according to claim 7, wherein the step of pre-treating the positive tab of the positive electrode tab and the negative tab of the negative electrode tab to form a pre-bent region parallel to the conveying direction comprises:

9. The method of claim 8, wherein a distance between two indentations is set to a, wherein 0 < a.ltoreq.0.5 mm.

10. The method of claim 9, wherein the diameter of the through hole is set to b, wherein b is less than or equal to a;

and/or the perforation is positioned at the middle position of the two indentations.

11. The battery cell processing method according to any one of claims 6 to 10, wherein after the step of conveying the positive electrode sheet and the negative electrode sheet, respectively, the positive electrode tab of the conveyed positive electrode sheet and the negative electrode tab of the conveyed negative electrode sheet are bent so that the positive electrode tab and the positive electrode sheet are disposed at an angle, and before the step of disposing the negative electrode tab and the negative electrode sheet at an angle, the method further comprises:

12. The method of claim 11, wherein the step of slitting the positive and negative electrode sheets so that the widths of the positive tab at the edge of the positive electrode sheet and the negative tab at the edge of the negative electrode sheet have an increasing tendency in a direction away from the conveyance comprises:

13. The method for processing a battery cell according to claim 12, wherein the diameter of the winding needle is set to L, the thickness of the positive electrode sheet is set to M1, the thickness of the negative electrode sheet is set to M2, and the winding number of turns of the battery cell is set to N;

14. The battery cell processing method according to any one of claims 6 to 10, wherein bending the positive tab of the positive electrode sheet and the negative tab of the negative electrode sheet so that the positive tab and the positive sheet form an angle, the negative tab and the negative sheet form an angle, comprises:

15. The method according to any one of claims 6 to 10, wherein the step of winding the positive electrode sheet, the negative electrode sheet, and the separator using a winding needle to form a bare cell and welding the bent positive electrode tab and negative electrode tab, respectively, comprises:

16. A cell prepared using the cell processing method of any one of claims 6 to 15.

17. A battery comprising the cell of claim 16.

18. A powered device comprising the battery of claim 17 or the cell of claim 16.