CN115020630A

CN115020630A - Pole piece and pole piece unit processing method, pole piece, battery and pole lug roller cutting device

Info

Publication number: CN115020630A
Application number: CN202210725980.6A
Authority: CN
Inventors: 郑俊超; 郭苗苗
Original assignee: Sany Technology Equipment Co Ltd
Current assignee: Sany Technology Equipment Co Ltd
Priority date: 2022-06-23
Filing date: 2022-06-23
Publication date: 2022-09-06
Anticipated expiration: 2042-06-23
Also published as: CN115020630B

Abstract

The invention provides a pole piece and pole piece unit processing method, a pole piece, a battery and a pole lug rolling cutting device, wherein the pole piece processing method comprises the following steps: step S1: coating an electrode material on the metal foil to form a coating layer on the metal foil, wherein the end part of the metal foil is exposed out of the coating layer and forms a hollow foil area; step S2: and cutting the empty foil area and forming the tab. Because the metal foil material is softer, and the coating layer of pole piece makes and has certain distance between utmost point ear and the diaphragm, consequently can not produce the risk that the diaphragm was impaled to the cutting department. In addition, because the coating layer is not cut any more, the coating layer does not need to be thinned at the edge, so that the coating head of the coating machine can be simplified, and the cost is reduced.

Description

Pole piece and pole piece unit processing method, pole piece, battery and pole lug roller cutting device

Technical Field

The invention relates to the technical field of tab processing equipment, in particular to a processing method of a pole piece and a pole piece unit, a pole piece, a battery and a tab roll cutting device.

Background

The tab cutting is one of the battery production processes, and comprises the processes of laser cutting, hardware die cutting and the like. The pole piece comprises a metal foil and a coating layer coated on the metal foil, wherein two ends of the metal foil are exposed out of the coating layer to form a hollow foil area. In order to increase the energy density of the battery, in the prior art, when cutting the tab, not only the empty foil region but also the edge portion of the coating layer is cut by a small amount. Because a certain height difference exists between the coating layer and the empty foil area, the roller cutting or die cutting cannot be carried out, so that in the actual process, a thinning layer needs to be formed at the edge part of the coating layer, and the height difference between the coating layer and the empty foil area is reduced. The thinning layer needs to adopt a special design on a coating head of the coating machine, and the thinning layer is formed on the edge of a coating layer during coating.

Further, since the coating layer and the empty foil area are cut together when the tab is cut in the prior art, hard burrs are generated at the cut part of the coating layer after the cutting. During subsequent lamination, the hard bristles are in direct contact with the membrane and easily pierce the membrane, and cause the problem of short circuit of the cell.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defect that the electrode lug in the prior art is easy to generate hard burrs after being processed, so that the electric core is short-circuited, thereby providing a processing method of a pole piece and a pole piece unit, a pole piece, a battery and a pole lug roll-cutting device.

In order to solve the above problems, the present invention provides a method for processing a pole piece, comprising: step S1: coating an electrode material on a metal foil to form a coating layer on the metal foil, wherein two ends of the metal foil are exposed out of the coating layer and form a hollow foil area; step S2: and cutting the empty foil area and forming the tab.

Optionally, after the cutting of the empty foil area, the outer end of the empty foil area protrudes beyond the coating layer by a distance in the range of 0.5mm to 1 mm.

Optionally, in step S1, the electrode material is uniformly coated on the metal foil.

Alternatively, in step S2, tabs are formed on the metal foil by roll cutting.

The invention also provides a pole piece, and the pole piece is manufactured by the processing method of the pole piece.

The invention also provides a processing method of the pole piece unit, the pole piece unit is formed by compounding and cutting the positive pole piece, the diaphragm and the negative pole piece, and the positive pole piece and the negative pole piece are manufactured by the processing method.

The invention also provides a processing method of the pole piece unit, which is characterized by comprising the following steps: step A1: compounding the negative plate and the diaphragm, and then cutting to form a complex; step A2: and cutting the positive plate, compounding the positive plate and the complex body, and obtaining a plate unit, wherein the positive plate and the negative plate are manufactured by the processing method of the plate.

Optionally, in step a1, the edges of the negative electrode sheet and the separator are flush after cutting.

Alternatively, in step a1, the combined negative electrode sheet and separator are cut in the width direction.

Optionally, the area of the composite is larger than the area of the positive electrode sheet and covers the positive electrode sheet.

The invention also provides a battery which comprises the pole piece, and the pole piece is manufactured by the processing method of the pole piece.

The invention also provides a pole lug rolling cutting device, which is used for processing the pole piece processing method and comprises the following steps: the end part of the first cutting roller is provided with a male die; and a second cutting roller arranged in parallel with the first cutting roller, wherein a female die is arranged at the end part of the second cutting roller, and in the step S2, when the pole piece passes through the first cutting roller and the second cutting roller, the male die and the female die are positioned in the empty foil area.

Optionally, the male die comprises a first male die section and a second male die section extending along the circumferential direction of the first cutting roller, the female die comprises a first female die section and a second female die section extending along the circumferential direction of the second cutting roller, the first female die section is matched with the first male die section, the second female die section is matched with the second male die section, and the first male die section and the second male die section are arranged at intervals so that tabs are formed on the empty foil area after the male die and the female die are cut.

Optionally, the first cutting roller comprises a first roller body and a first template, the first template is detachably connected to the first roller body, and a male die is arranged on the first template; the second cutting roller comprises a second roller body and a second template, the second template is detachably connected to the second roller body, and a female die is arranged on the second template.

The invention also provides a polar battery production line which comprises the polar lug roll-cutting device.

The invention has the following advantages:

by utilizing the technical scheme of the invention, when the pole piece is manufactured, the electrode material is coated on the metal foil to form the coating layer, two ends of the metal foil are exposed out of the coating layer to form the empty foil area, and when the pole lug is processed, only the empty foil area is cut to form the pole lug. Because the metal foil material is softer, and the coating layer of pole piece makes and has certain distance between utmost point ear and the diaphragm, consequently can not produce the risk that the diaphragm was impaled to the cutting department. In addition, because the coating layer is not cut any more, the coating layer does not need to be thinned at the edge, so that the coating head of the coating machine can be simplified, and the cost is reduced. Therefore, the technical scheme of the invention overcomes the defects that the electrode lug in the prior art is easy to generate hard burrs after use and causes short circuit of 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 used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 shows a schematic flow diagram of a tab processing method of the present invention;

FIG. 2 is a schematic structural diagram of a pole piece after being processed by the processing method of the present invention;

FIG. 3 shows an enlarged schematic view at A in FIG. 2;

fig. 4 is a schematic structural view illustrating a tab rolling cutting device of the present invention;

fig. 5 is a schematic structural view illustrating a first mold plate of the tab roll cutting device of fig. 4;

FIG. 6 shows an enlarged schematic view at B in FIG. 5;

fig. 7 is a schematic structural view illustrating a second mold plate of the tab roll cutting apparatus of fig. 4; and

fig. 8 shows an enlarged schematic view at C in fig. 7.

Description of reference numerals:

10. a first cutting roller; 11. a first roller body; 12. a first template; 121. a first half template; 13. a male die; 131. a first male mold section; 132. a second male mold section; 20. a second cutting roller; 21. a second roller body; 22. a second template; 221. a second half template; 23. a female die; 231. a first cavity die section; 232. a second cavity die section; 30. a first positioning structure; 40. a second positioning structure; 100. pole pieces; 101. a coating layer; 102. a foil empty region; 200. and (7) a tab.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

As shown in fig. 1 to 3, a method for processing a pole piece includes: step S1: coating an electrode material on a metal foil to form a coating layer 101 on the metal foil, wherein the end of the metal foil is exposed out of the coating layer 101 and forms a hollow foil region 102; step S2: the blank foil area 102 is cut and the tab 200 is formed.

By using the technical scheme of the embodiment, when manufacturing the pole piece, the electrode material is coated on the metal foil to form the coating layer 101, two ends of the metal foil are exposed out of the coating layer 101 to form the empty foil area 102, and when processing the tab, only the empty foil area 102 is cut to form the tab 200. Because the metal foil material is softer, and the coating layer 101 of pole piece makes certain distance between utmost point ear 200 and the diaphragm, consequently can not produce the risk that the cutting department pierces through the diaphragm. In addition, since the coating layer 101 is not cut any more, the coating layer 101 does not need to be thinned at the processing edge, so that the coating head of the coating machine can be simplified and the cost can be reduced. Therefore, the technical scheme of the embodiment solves the defects that hard burrs are easily generated after the tab in the prior art is used, and the short circuit of the battery cell is caused.

In particular, the technical solution of the present example has the following advantages:

1. because the coating layer 101 is not cut any more when the tab 200 is cut, the coating layer 101 does not need to be thinned, and a coating head of a coating machine does not need to be designed with a special structure, so that the structure is simplified and the cost is reduced;

2. in the embodiment, the cut tab 200 only cuts the empty foil area 102, so that the problem of height difference existing in the prior art when the coating layer 101 and the empty foil area 102 are simultaneously cut does not exist. Therefore, the machining precision can be easily controlled in both laser cutting and hardware die cutting. And the cut waste materials are all metal foils, which is beneficial to waste recovery.

3. The cutting of the tab 200 in this embodiment cuts only the empty foil area 102, and even if burrs are generated, the subsequent lamination does not pierce the membrane. Specifically, the texture of the metal foil is soft, and meanwhile, the coating layer 101 enables a space to exist between the tab 200 and the diaphragm (the thickness of the coating layer 101 is about 70 micrometers, and the length of burrs is about 10 micrometers), so that the burrs cannot exceed the coating layer, and the burrs cannot contact the coating layer during hot-pressing.

4. Because the burr on utmost point ear 200 does not have the risk of impaling the diaphragm, consequently can reduce the processing fineness of utmost point ear 200's chamfer, and then can reduce the mould precision of five metals cross cutting, reduce cost.

In addition, in the prior art, since hard burrs are generated after the tab 200 is cut, the four corners of the pole piece 100 need to be chamfered. The chamfering process requires additional processes, so that the pole piece processing step is complicated. In the embodiment, the burrs of the cut tab 200 do not pierce the separator, so that the pole piece 100 does not need to be chamfered or filleted.

The "end portion of the metal foil" means an end portion of the metal foil in the width direction. The end portion may be one end or both ends.

Further, in step S1, the tab 100 is divided into a positive tab and a negative tab depending on the material of the coating layer 101.

As shown in fig. 2 and 3, after the cutting of the empty foil area 102, the outer end of the empty foil area 102 protrudes from the coating layer 101 by a distance in the range of 0.5mm to 1 mm.

Preferably, in step S1, the electrode material is uniformly coated on the metal foil. As described above, since it is not necessary to apply the thinning layer of the coating layer 101 in the process in this example, it is sufficient to uniformly coat the electrode material on the metal foil, and the structure of the coating head of the coater can be simplified.

Preferably, in step S2, the tab 200 is formed on the empty foil area 102 by roll cutting. During processing, the pole piece 100 passes through a cutting roller, and the concave-convex die on the cutting roller only rolls and cuts the hollow foil area 102, but does not roll and cut the coating layer 101.

Of course, other conventional processing methods may be used for cutting in step S2, such as laser cutting, hardware die cutting, and so on.

The embodiment also provides a pole piece, and the pole piece is manufactured by the pole piece processing method.

The embodiment also provides a processing method of the pole piece unit, the pole piece unit is formed by compounding and cutting the positive pole piece, the diaphragm and the negative pole piece, and the positive pole piece and the negative pole piece are manufactured by the processing method.

As described above, since the four corners of the pole piece 100 in this embodiment do not need to be chamfered, the positive plate material strip with the cut tabs 200, the negative plate material strip with the cut tabs 200, and the separator material strip can be unwound at the same time, the positive plate and the negative plate are cut after unwinding, and then the cut positive plate and the cut negative plate are combined. And after the compounding is finished, cutting and cutting the diaphragm between the adjacent positive plates. And cutting to form the pole piece units in the forms of the positive pole piece, the diaphragm and the negative pole piece.

Compared with the prior art in which the positive plate and the negative plate are cut and chamfered first and then are subjected to composite processing with the diaphragm, the processing method of the pole piece unit of the embodiment greatly improves the production efficiency of the pole piece unit.

In addition, the separator in this example has an area larger than the areas of the positive and negative plates and covers the positive and negative plates to prevent contact short at the edges of the positive and negative plates of the plate unit.

The embodiment also provides another processing method of the pole piece unit, which is different from the processing method of the pole piece unit in a certain degree, and specifically, the processing method includes:

step A1: compounding the negative plate and the diaphragm, and then cutting to form a complex;

step A2: and cutting the positive plate, compounding the positive plate and the complex, and obtaining a pole piece unit.

The positive plate and the negative plate are manufactured by the processing method of the pole piece.

In the processing method of the pole piece unit, the negative pole piece and the diaphragm are compounded and cut, so that a compound body of the negative pole piece and the diaphragm is obtained.

Preferably, in step a1, the edges of the negative electrode sheet and the separator are flush after cutting. Because in this embodiment, the edge of pole piece no longer need fillet or chamfer V angle, consequently can directly cut negative pole piece and diaphragm after the complex, also make the edge parallel and level of negative pole piece and diaphragm.

Preferably, in step a1, the negative electrode sheet and the separator after being combined are cut in the width direction, and then the negative electrode sheet and the separator after being combined are cut into a sheet-shaped composite.

Preferably, the composite has an area larger than that of the positive electrode tab and covers the positive electrode tab. That is, the area of the separator is larger than that of the positive electrode plate, so that the edges of the positive electrode plate and the negative electrode plate can be prevented from contacting, and short circuit can be prevented.

In addition, the cost of the electrode material of the negative plate is higher than that of the electrode material of the positive plate, and in the processing method of the pole piece unit, the waste of the electrode material of the negative plate is less, so that the overall production cost can be reduced.

The embodiment also provides a battery which comprises a pole piece, wherein the pole piece is manufactured by the pole piece processing method.

As shown in fig. 4, the present embodiment further provides a tab rolling and cutting device, and is used for performing step S2 of the above processing method of the pole piece. Including a first cutting roll 10 and a second cutting roll 20. The first cutting roller 10 comprises a first roller body 11 and a first template 12, the first template 12 is detachably connected to the first roller body 11, and a male die 13 is arranged on the first template 12. The second cutting roller 20 is arranged in parallel with the first cutting roller 10, the second cutting roller 20 comprises a second roller body 21 and a second template 22, the second template 22 is detachably connected to the second roller body 21, a female die 23 is arranged on the second template 22, and the female die 23 is matched with the male die 13.

As shown in fig. 5 to 8, in the solution of the present embodiment, the male mold 13 includes a first male mold section 131 and a second male mold section 132 disposed at the end of the first half mold plate 121, and the first male mold section 131 and the second male mold section 132 are disposed at intervals. The cavity die 23 includes a first cavity die section 231 and a second cavity die section 232 disposed at ends of the second half die plate 221, and the first cavity die section 231 and the second cavity die section 232 are disposed at intervals. The first male die section 131 mates with the first female die section 231 and the second male die section 132 mates with the second female die section 232. The gap between the first and

second die segments

231 and 232 allows the tab 200 to be formed after cutting

In this embodiment, the male die 13 and the female die 23 only roll-cut the empty foil area 102 of the pole piece 100, which can improve the cutting quality of the tab 200 and the service life of the tab roll-cutting device. Meanwhile, the waste materials after the roller cutting are all pure metal foils, so that the collection and treatment of the waste materials can be facilitated.

In addition, taking the first cutting roller 10 as an example, when the male die 13 is worn or damaged, the first die plate 12 is detached from the first roller body 11, and the first cutting roller 10 can continue to work by replacing the new first die plate 12 without replacing the whole first cutting roller 10. Similarly, when the female die 23 is worn or damaged, the second die plate 22 is replaced with a new one. The structure facilitates the trimming or replacement of the female die 23 and the male die 13, the first roller body 11 and the second roller body 21 do not need to be disassembled, and the use cost of the first cutting roller 10 and the second cutting roller 20 is greatly reduced. Therefore, the technical scheme of the embodiment also overcomes the defect that the tab cutting roller in the prior art is high in use cost.

During processing, the pole piece 100 is subjected to roll cutting by matching the first cutting roller 10 with the second cutting roller 20, and the male die 13 with the female die 23, so that the pole piece 100 is subjected to roll cutting. Meanwhile, notches are arranged on the male die 13 and the female die 23, and tabs are formed at the notches after the roll cutting.

When the male die 13 is worn, the first die plate 12 is detached from the first roller body 11, and the male die 13 is trimmed and then installed back to the first roller body 11, or a new first die plate 12 is directly replaced. Meanwhile, if the male die 13 is damaged, the first cutting roller 10 cannot be scrapped.

When the die 23 is worn, the second template 22 is detached from the second roller body 21, and the die 23 is trimmed and then mounted back to the second roller body 21, or a new second template 22 is directly replaced. Meanwhile, if the female die 23 is damaged, the second cutting roller 20 cannot be scrapped.

Preferably, a first magnetic member is disposed between the first roller body 11 and the first mold plate 12. The first magnetic member can make the first template 12 be adsorbed on the first roller body 11, thereby realizing the quick installation and the quick removal of the first template 12 relative to the first roller body 11.

Preferably, a second magnetic member is disposed between the second roller body 21 and the second template 22. The second magnetic member may cause the second template 22 to be attracted to the second roller body 21, thereby enabling the second template 22 to be quickly attached and detached with respect to the second roller body 21.

Of course, the first roller body 11 and the first mold plate 12, and the second roller body 21 and the second mold plate 22 may be connected in other ways, such as by conventional fasteners such as screws, snaps, and the like.

As shown in fig. 5 to 7, in the solution of the present embodiment, a first positioning structure 30 is provided between the first roller body 11 and the first template 12, and a second positioning structure 40 is provided between the second roller body 21 and the second template 22.

The first positioning structure 30 can fix the first pattern plate 12 at a predetermined position of the first roller body 11, and the second positioning structure 40 can fix the second pattern plate 22 at a predetermined position of the second roller body 21, so that the male mold 13 and the female mold 23 can be engaged with each other when the first cutting roller 10 and the second cutting roller 20 are rotated.

As shown in fig. 6, in the solution of the present embodiment, the first positioning structure 30 includes a first positioning protrusion disposed on the first roller body 11, and a first positioning hole disposed on the first mold plate 12. When the first positioning protrusion is installed, the first positioning protrusion is inserted into the first positioning hole, so as to fix the relative positions of the first template 12 and the first roller 11, and then the two are connected through the first magnetic member.

As shown in fig. 6, in the solution of the present embodiment, the second positioning structure 40 includes a second positioning protrusion disposed on the second roller body 21, and a second positioning hole disposed on the second template 22. When the roller is mounted, the second positioning protrusion is inserted into the second positioning hole, so as to fix the relative positions of the second template 22 and the second roller 21, and then the two are connected by the second magnetic member.

Of course, the first positioning structure 30 and the second positioning structure 40 may also be conventional structures such as a rib and a slot.

As shown in fig. 5 and fig. 6, in the technical solution of the present embodiment, the first mold plate 12 includes two first mold half plates 121, the first mold half plates 121 are in an arc-shaped plate structure, and the two first mold half plates 121 are fastened outside the first roller body.

Specifically, the first half mold plates 121 are half-cylinder structures, and the two first half mold plates 121 can be symmetrically buckled outside the first roller 11. The first half form 121 is shaped so that it can be installed and removed from the outside of the first cutting roll 10, and thus the rotating shaft of the first roll body 11 is not removed when the first form 12 is replaced, thereby facilitating the installation and removal. Each first half die plate 121 is provided with the first positioning hole, and meanwhile, each first half die plate 121 is assembled on the first roller body 11 through the first magnetic member.

As shown in fig. 7, in the solution of the present embodiment, the male die 13 includes a first male die section 131 and a second male die section 132 disposed at the end of the first half die plate 121, and the first male die section 131 and the second male die section 132 are disposed at an interval to form the tab 200 on the pole piece 100. Specifically, the first and second

male mold segments

131 and 132 are each provided at an end position of the first half mold plate 121, and both extend in the circumferential direction. The first and

second die segments

131 and 132 have a gap therebetween, so that the tab is formed in the gap between the first and

second die segments

131 and 132 after the pole piece passes through the first and second cutting rollers 10 and 20 (as shown in fig. 6).

Further, the length of the first section 131 is smaller than that of the second section 132. It will be understood by those skilled in the art that the distance between the adjacent tabs 200 can be adjusted by adjusting the lengths of the first and second die

sections

131 and 132.

Further, the first male mold section 131 and the second male mold section 132 are each formed by an annular convex edge on the outer wall of the first mold half 121.

In addition, as will be understood by those skilled in the art with reference to fig. 2 and 6, after the two first half die plates 121 are assembled, the first male die section 131 on one first half die plate 121 has a gap with the second male die section 132 on the other first half die plate 121, so that when the pole piece 100 is roll-cut, a narrow strip of material is formed beside the tab 200, and the narrow strip of material is cut off in a subsequent process.

As shown in fig. 7 and 8, in the technical solution of the present embodiment, the second form 22 includes two second form halves 221, the second form half 221 is an arc-shaped plate structure, and the two second form halves 221 are fastened outside the second roller body 21.

Specifically, the second half mold plates 221 are half-cylinder structures, and the two second half mold plates 221 may be symmetrically fastened outside the second roller body 21. The second half pattern plate 221 is shaped so as to be attachable and detachable from the outside of the second cutting roller 20, and thus the rotating shaft of the second roller body 21 is not detached when the second pattern plate 22 is replaced, thereby facilitating the detachment and detachment. Each second half mold plate 221 is provided with the above-mentioned second positioning hole, and meanwhile, each second half mold plate 221 is assembled on the second roller body 21 through the second magnetic member.

As shown in fig. 8, in the solution of the present embodiment, the die 23 includes a first die segment 231 and a second die segment 232 disposed at the end of the second die half 221, and the first die segment 231 and the second die segment 232 are disposed at an interval to form the tab 200 on the pole piece 100. Specifically, the first cavity section 231 is for mating with the first male mold section 131, and the second cavity section 232 is for mating with the second male mold section 132. The first cavity mold section 231 and the second cavity mold section 232 are arranged in the same manner as the first convex mold section 131 and the second convex mold section 132, and thus, the description thereof is omitted.

Preferably, the first cavity segment 231 and the second cavity segment 232 both penetrate the surface of the second mold half 221.

Preferably, the first half mold 121 and the second half mold 221 are made of soft material. Preferably, the first half mold plate 121 and the second half mold plate 221 are made of mild steel.

Further, the processing mode of the tab rolling and cutting device in this embodiment to the tab is different from the prior art, specifically as follows:

the pole piece comprises a metal foil and a coating layer 101 coated on the metal foil, wherein a part of the foil protruding out of the coating layer 101 forms a hollow foil area 102, when the cutting roller in the prior art is used, the coating layer 101 and the hollow foil area 102 are cut together, and after cutting, hard burrs are generated at the cutting part of the edge of the coating layer 101. When the subsequent lamination is carried out, the hard burrs are directly contacted with the diaphragm and easily pierce the diaphragm, and the problem of short circuit of the battery cell is caused.

In the embodiment, the male die 13 of the first cutting roller 10 and the female die 23 of the second cutting roller 20 directly cut the empty foil area 102 of the pole piece 100, but do not cut the coating layer 101 of the pole piece 100. During relative rolling of the first cutting roll 10 and the second cutting roll 20, the first male die section 131 and the first female die section 231 cooperate and cut the blank foil region 102, and the second male die section 132 and the second female die section 232 cooperate and cut the blank foil region 102. The gap between the first and

second die segments

131 and 132 allows the tab 200 to be formed after cutting. Because the metal foil material is softer, and the coating layer 101 of the pole piece 100 enables a certain distance to be reserved between the tab 200 and the diaphragm (the thickness of the coating layer 101 is about 70 micrometers, and the burr length of the foil is about 10 micrometers), the risk that the diaphragm is pierced at the cutting position cannot be caused by subsequent lamination. Therefore, the scheme of the embodiment can overcome the defect that hard burrs are easily generated after the pole lugs are cut by the pole lug cutting roller in the prior art, and the short circuit of the battery cell is caused.

The embodiment also provides a battery production line, which comprises the tab roller cutting device.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. A processing method of a pole piece is characterized by comprising the following steps:

step S1: coating an electrode material on a metal foil to form a coating layer (101) on the metal foil, wherein the end of the metal foil is exposed out of the coating layer (101) and forms a hollow foil region (102);

step S2: cutting the empty foil area (102) and forming a tab (200).

2. The process according to claim 1, wherein the outer end of the foil-free region (102) protrudes beyond the coating layer (101) after cutting of the foil-free region (102) by a distance in the range of 0.5mm to 1 mm.

3. The process of claim 1, wherein in step S1, an electrode material is uniformly coated on the metal foil.

4. The process according to claim 1, wherein in step S2, the tab (200) is formed on the metal foil by roll cutting.

5. A pole piece manufactured by the processing method of the pole piece according to any one of claims 1 to 4.

6. A processing method of a pole piece unit, characterized in that the pole piece unit is formed by compounding and cutting a positive pole piece, a diaphragm and a negative pole piece, wherein the positive pole piece and the negative pole piece are manufactured by the processing method of the pole piece according to any one of claims 1 to 4.

7. A processing method of a pole piece unit is characterized by comprising the following steps:

step A2: cutting the positive plate, compounding the positive plate and the complex to obtain a plate unit,

wherein the positive electrode sheet and the negative electrode sheet are manufactured by the processing method of the electrode sheet according to any one of claims 1 to 4.

8. The manufacturing method according to claim 7, wherein in step A1, the edges of the negative electrode sheet and the separator are flush after cutting.

9. The manufacturing method according to claim 7, wherein in step A1, the negative electrode sheet and the separator after being combined are cut in the width direction.

10. The processing method according to claim 7, wherein the composite has an area larger than that of the positive electrode sheet and covers the positive electrode sheet.

11. A battery, characterized by comprising a pole piece manufactured by the processing method of the pole piece according to any one of claims 1 to 4.

12. A tab rolling and cutting device for carrying out the processing method of the pole piece according to any one of claims 1 to 4, comprising:

the cutting device comprises a first cutting roller (10), wherein a male die (13) is arranged at the end part of the first cutting roller (10);

a second cutting roller (20) arranged in parallel with the first cutting roller (10), a concave die (23) arranged at the end part of the second cutting roller (20),

in the step S2, when the pole piece (100) passes through the first cutting roller (10) and the second cutting roller (20), the convex die (13) and the concave die (23) are positioned in the empty foil area (102).

13. The tab roll cutting device as claimed in claim 12,

the male die (13) comprises a first male die section (131) and a second male die section (132) extending in the circumferential direction of the first cutting roll (10),

the female die (23) comprises a first female die section (231) and a second female die section (232) extending in the circumferential direction of the second cutting roll (20), the first female die section (231) and the first male die section (131) are matched, the second female die section (232) and the second male die section (132) are matched,

the first male die section (131) and the second male die section (132) are arranged at intervals, so that the tabs (200) are formed on the empty foil area (102) after the male die (13) and the female die (23) are cut.

14. The tab roll cutting device according to claim 12, characterized in that the first cutting roll (10) comprises a first roll body (11) and a first template (12), the first template (12) being detachably connected to the first roll body (11), the first template (12) being provided with the male die (13);

the second cutting roller (20) comprises a second roller body (21) and a second template (22), the second template (22) is detachably connected to the second roller body (21), and the female die (23) is arranged on the second template (22).

15. A polar battery production line, characterized by comprising a tab roll cutting apparatus as claimed in any one of claims 12 to 14.