CN115837402B

CN115837402B - Compression roller, rolling device and manufacturing method of pole piece

Info

Publication number: CN115837402B
Application number: CN202111473636.4A
Authority: CN
Inventors: 郑超蜜
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2023-12-05
Anticipated expiration: 2041-11-29
Also published as: WO2023093338A1; CN115837402A

Abstract

The application provides a press roller and a rolling device for rolling a battery pole piece, and a manufacturing method of the pole piece. The press roll provided in the first aspect of the application comprises a main body part, a roll lamination and a containing cavity. The body portion has a channel for inputting or outputting a fluid. The roll-in layer sets up in the outside of main part and is used for the roll-in pole piece, and the roll-in layer forms with the surface of main part and holds the chamber, holds chamber and passageway intercommunication. Wherein the fluid is configured to flow into or out of the receiving cavity via the channel to deform the roll nip. The volume of the containing cavity is variable, so that the concave-convex state of the press roller can be changed, and different rolling pressures can be applied to different positions and different degrees of wavy edges on the pole piece.

Description

Compression roller, rolling device and manufacturing method of pole piece

Technical Field

The application relates to the technical field of battery production, in particular to a press roller and a rolling device for rolling a pole piece of a battery and a manufacturing method of the pole piece.

Background

The manufacturing of the battery pole piece is generally to uniformly coat the slurry on two sides of an aluminum or copper current collector according to a certain pole piece surface density, and remove the solvent in the slurry by baking; the coiled pole piece is continuously rolled to the specified thickness by a pair roller machine, and then is formed after being connected with the pole lugs in a splitting way. In the flaking process, the middle and two sides of the pole piece coating area can generate the phenomenon of pole piece wavy edges due to the difference of the extensibility, namely, the winding deviation correcting is abnormal or wrinkling is carried out, and then the quality of the pole piece is poor or the safety problem of a battery is caused. Therefore, how to improve the defect of the wavy edge of the battery pole piece in production is a problem to be solved.

Disclosure of Invention

In view of the above, the present application provides a press roller for rolling a battery pole piece.

The first aspect of the present application provides a press roll for rolling a pole piece of a battery. The press roll comprises a body part, a roll lamination and a receiving cavity. The body portion has a channel for inputting or outputting a fluid. The roll-in layer sets up in the outside of main part and is used for the roll-in pole piece, and the roll-in layer forms with the surface of main part and holds the chamber, holds chamber and passageway intercommunication. Wherein the fluid is configured to flow into or out of the receiving cavity via the channel to deform the roll nip. The volume of the containing cavity is variable, so that the concave-convex state of the press roller can be changed, and different rolling pressures can be applied to different positions and different degrees of wavy edges on the pole piece.

Optionally, the body portion includes an inner post and a support post. The inner column is disposed inside the main body. The support columns are used for supporting the roll layering. One end of the support column is connected with the inner column, and the other end is connected with the roll lamination. Wherein, inner column, support column and roll-in layer enclose jointly and hold the chamber.

Optionally, the channels include a first channel and a second channel. The first channel is arranged in the inner cavity of the inner column and extends along the axial direction of the inner column. The second channel is arranged in the inner cavity of the support column and extends along the radial direction of the support column. The first channel is communicated with the second channel, the second channel is communicated with the accommodating cavity, and fluid enters the accommodating cavity through the first channel and the second channel to squeeze the roll-in layer.

Optionally, the support column includes first support column and second support column of mutual separation, and first support column is solid structure, and the second passageway sets up in the inner chamber of second support column. The embodiment can remarkably enhance the structural strength of the press roller.

The second aspect of the application provides a rolling device for pole pieces of a battery. The rolling device comprises a rolling module comprising a press roll according to any of the above embodiments, the press roll being for rolling a pole piece.

Optionally, the rolling module further comprises a storage unit and a control unit. The storage unit is configured to store a fluid. The control unit is used for controlling the storage unit to pump or inject fluid into the compression roller. The configuration storage unit and the control unit can accurately control the concave-convex degree of the compression roller, so that the wavy edges of the pole pieces can be corrected more accurately.

Optionally, the rolling device further comprises a detection module, and the detection module is used for detecting the extensibility of the pole piece and feeding back to the control unit. The configuration detection module can accurately collect the severity of the wavy edge defect of the pole piece, and is beneficial to accurately correcting the wavy edge of the pole piece by the rolling module.

Optionally, the detection module includes a coded wheel set and an information processing unit. The coding wheel group is used for contacting with the pole piece and detecting the extensibility of the pole piece. The information processing unit is used for collecting detection information of the coding wheel set and feeding the detection information back to the control unit after processing. The configuration coding wheel group and the information processing unit can accurately collect the wavy edge position of the pole piece, and the rolling module can accurately correct the wavy edge of the pole piece.

Optionally, the detection module includes at least two sets of coding wheelsets, one set of coding wheelsets is disposed on the surface of the pole piece at the upstream of the press roller, and the other set of coding wheelsets is disposed on the surface of the pole piece at the downstream of the press roller. The correction effect of the compression roller on the pole piece can be known by arranging the coding wheel sets on the surfaces of the pole pieces at the upstream and downstream of the compression roller, and the pole piece wave edges can be corrected more accurately by the rolling module.

A third aspect of the application provides a method of manufacturing a pole piece. The method of manufacture comprises providing a pole piece and providing a press roll of any of the above embodiments, and rolling the pole piece using the press roll.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

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

fig. 1 is a perspective view of a press roller for rolling a battery pole piece according to the present application;

FIG. 2 is a cross-sectional view of the press roll of FIG. 1;

fig. 3 is a schematic view of a flat roll state, a concave roll state, and a convex roll state of the press roll, wherein fig. 3 (a) is a schematic view of a concave roll state of the press roll, fig. 3 (b) is a schematic view of a flat roll state of the press roll, and fig. 3 (c) is a schematic view of a convex roll state of the press roll;

fig. 4 is a schematic structural diagram of a rolling device for a battery pole piece according to the present application;

FIG. 5 is a schematic diagram illustrating the operation of a encoder wheel set according to the present application;

fig. 6 is a schematic flow chart of a method for manufacturing a pole piece according to the present application.

Reference numerals in the specific embodiments are as follows:

1000 rolling devices, 1 pole piece and 2 film areas;

10 press rolls, 11 main body, 110 channels, 1101 first channels, 1102 second channels, 111 inner columns, 112 support columns, 1121 first support columns, 1122 second support columns, 12 roll layering, 13 receiving cavities;

100 roll-in modules, 20 storage units and 30 control units;

the device comprises a detection module 200, a coding wheel set 210, a coding wheel 211 and an information processing unit 220;

300 differential stretch modules, 400 cold press modules.

Detailed Description

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

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

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

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

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

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

In the existing battery pole piece production process, a common rolling device can only solve the problem of wavy edges at fixed positions in a pole piece coating region, but cannot solve the problem of wavy edges at unfixed complicated positions. For example, the rolling device can only roll the wavy edge positioned in the middle of the pole piece coating area after being installed, and the wavy edge positioned at the edge of the pole piece coating area cannot be treated. However, in actual production, the position of the wavy edge on the pole piece is not fixed, and the wavy edge may appear in the middle position of the pole piece coating area in part of the time period, and after a period of time, the wavy edge may appear in the edge position of the pole piece coating area. The existing rolling device can not solve the technical problem of pole piece wavy edges at various positions in the production process.

The applicant has found that it is possible to design a press roller having a position of the concavity and convexity and the convexity adjusting roller to solve the above-mentioned problems. The compression roller can be provided with under the outer roll-in layer and hold the chamber, hold the intracavity and pour into like hydraulic oil fluid into, can change the roll-in pressure that the roll-in layer applyed to the polar plate through changing the volume size that holds intracavity fluid: when the volume of the fluid is a certain volume, the compression roller is a flat roller; on the basis of the volume of the fluid, injecting the fluid to enable the compression roller to be a convex roller; the fluid is pumped out to make the press roller be a concave roller. The concave-convex variable compression roller can be matched with the concavity and convexity of the roller according to the size and the position of the wavy edge of the pole piece so as to effectively correct the pole piece.

The present application provides a press roller 10 for rolling a pole piece 1 of a battery, and a rolling device 1000 and a rolling method S100 of a pole piece 1 of a battery including such a press roller 10. Such a press roller 10 is suitable for use in pole pieces 1 of any battery, such as primary and secondary batteries, including, for example, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid (or lead-storage) batteries, lithium ion batteries, sodium ion batteries, polymer batteries, and the like.

Referring to fig. 1 and 2, fig. 1 is a perspective view of a press roller 10 for rolling a pole piece 1 of a battery according to a first aspect of the present application, and fig. 2 is a cross-sectional view of the press roller 10 shown in fig. 1. The press roll 10 comprises a main body part 11, a roll layer 12 and a receiving chamber 13. The body portion 11 has a passage 110, the passage 110 being used for inputting or outputting fluid. The roll layer 12 is arranged on the outer side of the body part 11 for rolling the pole piece 1, the roll layer 12 and the outer surface of the body part 11 forming a receiving cavity 13, the receiving cavity 13 being in communication with the channel 110. Wherein the fluid is configured to flow into or out of the receiving cavity 13 via the channels 110 to deform the roll layer 12.

The press roll 10 is a roll with fluid as a conductive medium for the roll pressure. The pressure roller 10 indirectly applies pressure to the external pole piece through the fluid in the containing cavity 13: the fluid in the receiving cavity 13 applies pressure to the roll-laminated layer 12, which roll-laminated layer 12 in turn applies roll pressure to the pole piece 1. The fluid in the press roll 10 may be hydraulic oil or gas, the hydraulic oil may be various mineral oils, emulsion and synthetic hydraulic oil or other realizable media, and the gas may be hydrogen or helium, etc., and the present application is not limited thereto.

The roll layer 12 may be wrapped around the outside of the body portion 11. The roll layer 12 may be fixed in a fixing groove provided on the outside of the body 11, or may be fixed on the outside of the body 11 by means of gluing. The roll layer 12 is used to contact the pole piece 1 and roll the pole piece 1. The material of the roll layer 12 may be an elastic material such as rubber to deform when pressed by the fluid in the receiving chamber 13. The resilient material also prevents the roll-in layer 12 from scratching the pole piece 1 when the roll-in layer 12 is in contact with the pole piece 1.

At least part of the body portion 11 may be enclosed by the roll-laminated layer 12. The main body 11 may have a simple structure such as a cylinder or a rectangular parallelepiped, or may have a complex structure in which one cylinder is fitted over the other cylinder.

The receiving chamber 13 may be used for storing a fluid such as hydraulic oil. The volume of the receiving chamber 13 is variable.

The press roller 10 may be classified into a flat roller state, a concave roller state, and a convex roller state according to the volume of the receiving chamber 13. Referring to fig. 3, fig. 3 is a schematic view of a flat roll state, a concave roll state and a convex roll state of the press roll 10, wherein fig. 3 (a) is a schematic view of the concave roll state of the press roll 10, fig. 3 (b) is a schematic view of the flat roll state of the press roll 10, and fig. 3 (c) is a schematic view of the convex roll state of the press roll 10. In the flat roll state, the outer diameter L1 of the roll layer 12 is equal to the maximum outer diameter L2 of the body portion 11; in the gravure state, the outer diameter L1 of the roll layer 12 is smaller than the maximum outer diameter L2 of the body portion 11; in the raised roll state, the outer diameter L1 of the roll layer 12 is larger than the maximum outer diameter L2 of the body portion 11.

Since the volume of the accommodating cavity 13 is variable, the concave-convex state of the press roller 10 can be changed, so that different rolling pressures can be applied to different positions and different degrees of wavy edges on the surface of the pole piece 1.

Referring to fig. 2, the main body 11 may optionally include an inner post 111 and a support post 112. The inner column 111 is provided inside the main body 11. The support columns 112 are used to support the roll layer 12. One end of the support column 112 is connected to the inner column 111 and the other end is connected to the roll-in layer 12. Wherein the inner posts 111, the support posts 112 and the roll layer 12 together enclose a receiving cavity 13.

The inner column 111 may be provided in a hollow structure to store fluid such as hydraulic oil. The inner post 111 may be a cylinder, the outer diameter of the inner post 111 may be smaller than the outer diameter of the roll-in layer 12, the outer diameter of the inner post 111 may be smaller than the outer diameter of the support post 112, the length of the inner post 111 may be greater than the length of the roll-in layer 12, and the outer diameter of the inner post 111 may be smaller than the maximum outer diameter of the body portion 11.

The support column 112 may take on a circular configuration. The center of the inner circle of the support column 112 may coincide with the center of the inner circle of the inner column 111. The inner diameter of the support column 112 may be equal to the diameter of the inner column 111. The end of the support column 112 connected to the inner column 111 may extend in the radial direction Y of the inner column 111 towards the roll-in layer 12 and be connected to the roll-in layer 12. The outer diameter of the support column 112 may be equal to the maximum outer diameter L2 of the main body portion 11.

Referring to fig. 2, the channels 110 may optionally include a first channel 1101 and a second channel 1102. The first channel 1101 is disposed in the inner cavity of the inner column 111, and the first channel 1101 extends along the axial direction X of the inner column 111. The second channel 1102 is disposed in the inner cavity of the support column 112, and the second channel 1102 extends along the radial direction Y of the support column 112. Wherein the first channel 1101 is communicated with the second channel 1102, the second channel 1102 is communicated with the accommodating cavity 13, and fluid enters the accommodating cavity 13 through the first channel 1101 and the second channel 1102 to press the roll-in layer 12.

The inner diameter of the first channel 1101 may be smaller than the outer diameter of the inner post 111. The length of the first channel 1101 may be equal to the length of the inner post 111.

The inner diameter of the second channel 1102 may be smaller than the outer diameter of the support column 112. The length of the second channel 1102 may be equal to the length of the support column 112.

In some embodiments, a plurality of first liquid inlets (not shown) may be provided on the inner column 111, and the first liquid inlets may be used to inject or extract fluid such as hydraulic oil into or from the press roll 10. Fluid such as hydraulic oil enters the first passage 1101 through the first inlet port. The first liquid inlet hole may be circular, and the diameter of the first liquid inlet hole may be equal to the diameter of the circular section of the first passage 1101, and the diameter of the first liquid inlet hole may be smaller than the diameter of the circular section of the inner column 111.

In some embodiments, a plurality of second liquid inlets (not shown) may be disposed on the support column 112, where the second liquid inlets are used to communicate the second channel 1102 with the accommodating cavity 13, so as to facilitate the ingress and egress of the fluid such as hydraulic oil in the second channel 1102 and the accommodating cavity 13. The shape of the second inlet opening may be circular or rectangular or star-shaped, and the diameter of the second inlet opening may be smaller than the smallest distance between the roll layer 12 and the inner column 111. The support column 112 may be provided with a plurality of second liquid inlet holes, and the plurality of second liquid inlet holes may be distributed around the inner column 111.

Referring to fig. 3, alternatively, the support column 112 includes a first support column 1121 and a second support column 1122 separated from each other, the first support column 1121 is a solid structure, and the second channel 1102 is disposed in an inner cavity of the second support column 1122.

In some embodiments, the first support column 1121 may be a solid structure and the other portion of the support columns 1122 may be a hollow structure including the second channels 1102. The first support columns 1121 and the second support columns 1122 may be alternately arranged.

Compared to the solution in which all support columns 112 are hollow structures including the second channels 1102, the solution in which only part of support columns 112 are arranged to be hollow structures including the second channels 1102 can significantly enhance the structural strength of the press roller 10.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a rolling device 1000 for a pole piece 1 of a battery according to a second aspect of the present application. The rolling device 1000 comprises a rolling module 100, the rolling module 100 comprising a press roll 10 according to any of the above embodiments, the press roll 10 being used for rolling the pole piece 1.

Optionally, the rolling module 100 may further include a storage unit 20 and a control unit 30. The storage unit 20 is configured to store a fluid. The control unit 30 is used to control the storage unit 20 to draw or inject fluid into the nip roller 10.

The storage unit 20 may be a container including a chamber having a fluid for storing hydraulic oil, etc., and the storage unit 20 may include a pipe (not shown) connected to the platen roller 10, and the pipe may be in communication with the first passage 1101. The storage unit 20 may draw or inject fluid pressing the roll layer 12 from the first channel 1101 to the press roll 10 via a pipe.

A control unit 30 for controlling the speed and volume of the fluid drawn or injected from the storage unit 20 to the press roller 10 so that the press roller 10 has different degrees of concavity and convexity and is switched between a flat roller state, a concave roller state and a convex roller state.

The configuration of the storage unit 20 and the control unit 30 can precisely control the degree of concavity and convexity of the pressing roller 10, so that the wavy edges of the pole piece 1 can be corrected more precisely.

Referring to fig. 4, optionally, the rolling device 1000 further includes a detection module 200, and the detection module 200 is configured to detect the extensibility of the pole piece 1 and feed back the extensibility to the control unit 30.

The elongation is the percentage of the ratio of the total deformation of the stretched gauge length of the pole piece 1 to the length of the original gauge length. By detecting the extensibility of the pole piece 1, it is possible to know whether the surface of the pole piece 1 has the wavy edge defect or not and the severity of the wavy edge defect.

The configuration detection module 200 can accurately collect the severity of the wavy edge defect of the pole piece 1, and is beneficial to accurately correcting the wavy edge of the pole piece 1 by the rolling module 100.

Referring to fig. 4, optionally, the detection module 200 includes a coding wheel set 210 and an information processing unit 220. The encoder wheel set 210 is used to contact the pole piece 1 and detect the extensibility of the pole piece 1. The information processing unit 220 is configured to collect the detection information of the encoding wheel set 210, process the detection information, and feed the processed detection information back to the control unit 30.

Referring to fig. 5, fig. 5 is a schematic diagram illustrating the operation of a coding wheel set 210 according to the present application. As shown in fig. 5, the set of encoding wheel sets 210 may include at least two encoding wheels 211 disposed on both sides of the pole piece 1, respectively. The encoder wheel 211 is a device for calculating the number of turns and converting to obtain the length and the expansion rate of the strip-shaped material of the current pole piece 1 by utilizing the linkage of the wheel disc and the conveying roller of the pole piece 1.

The information processing unit 220 may include wires (not shown) connected to the encoder wheel set 210 and the control unit 30 to transmit signals. The information processing unit 220 processes the detection information after receiving the detection information of the encoding wheel set 210, and feeds back the processed information to the control unit 30, and the control unit 30 determines the degree of concavity and convexity of the pressing roller 10.

The configuration of the encoding wheel set 210 and the information processing unit 220 can accurately collect the wavy edge position of the pole piece 1, which is beneficial to the rolling module 100 to accurately correct the wavy edge of the pole piece 1.

Referring to fig. 4, the detection module 200 optionally includes at least two encoding wheel sets 210. One set of encoding wheel sets 210 is arranged on the surface of the pole piece 1 at the upstream of the press roller 10, and the other set of encoding wheel sets 210 is arranged on the surface of the pole piece 1 at the downstream of the press roller 10.

The encoding wheel set 210 disposed on the surface of the pole piece upstream of the press roller 10 is used to detect the position of the wavy edge of the pole piece 1, so that the rolling module 100 can adjust the state and the degree of concavity and convexity of the press roller 10. The coding wheel set 210 arranged on the surface of the pole piece at the downstream of the press roller 10 is used for detecting whether the surface of the pole piece 1 rolled by the press roller 10 has a wavy edge, detecting the correction effect of the press roller 10 on the pole piece 1, and feeding back to the rolling module 100 according to the detection result.

The coding wheel sets 210 are arranged on the surfaces of the pole pieces 1 at the upstream and downstream of the press roller 10, so that the correction effect of the press roller 10 on the pole pieces 1 can be collected, and the rolling module 100 can accurately correct the wavy edges of the pole pieces 1.

In some embodiments of the application, the pole piece 1 may comprise at least two membrane areas 2. The encoder wheel set 210 may include at least 3 pairs of encoder wheels 211. Each pair of coding wheels 211 comprises 2 coding wheels 211 respectively arranged on the two side surfaces of the pole piece 1. The number of the coding wheel sets 210 corresponds to the number of the film areas 2, and each coding wheel set 210 is used for detecting the extensibility of the pole piece 1 in one film area 2. In embodiments where the set of encoder wheel sets 210 includes 3 pairs of encoder wheels 211, one pair of encoder wheels 211 may be positioned in the middle of a single film section 2 and the other 2 pairs may be positioned on either side of the film section 2.

The film region 2 of the pole piece 1 refers to a region where a layer of film with specific materials of positive and negative electrodes is smeared on the surface of the pole piece 1. The pole piece 1 may have a plurality of film regions 2 during processing. Each film section 2 may be provided with a set of encoder wheel sets 210 to detect the elongation of the pole pieces 1 within that film section 2.

As shown in fig. 5, each group of encoding wheel sets 210 may include at least 3 pairs of encoding wheels 211, that is, 3 encoding wheels 211 are distributed on one side of the film region 2, and 3 encoding wheels 211,3 are also distributed on the opposite position of the other side of the film region 2, where the encoding wheels 211 are respectively disposed at the middle position and the two side edge positions of the film region 2.

The number of the coding wheel sets 210 corresponds to the number of the film areas 2, that is, at least one coding wheel set 210 in each film area 2 is used for detecting the extensibility of the pole piece 1 in the film area 2. For example, the detection module 200 may include 6 sets of encoding wheel sets 210, wherein 3 sets of encoding wheel sets 210 are respectively disposed on 3 film areas 2 of the pole piece 1 before the press roller 10, and another 3 sets of encoding wheel sets 210 are respectively disposed on 3 film areas 2 of the pole piece 1 after the press roller 10.

In some embodiments of the present application, as shown in fig. 4, the rolling device 1000 further includes a differential stretching module 300, and the differential stretching module 300 is used for performing a preliminary stretching treatment on the pole piece 1 before the rolling by the press roller 10.

The differential stretching module 300 comprises a main driving roller, a swinging roller, a tension roller, a two-stage (group) or three-stage (group) differential stretching mechanism and a plurality of passing rollers for steering the pole piece 1; the differential stretching mechanism of each stage (group) comprises a plurality of sets of differential rollers and rubber rollers which are mutually matched to clamp the pole piece 1, and the differential rollers in front of the advancing of the pole piece 1 are higher in rotating speed due to different rotating speeds of the differential rollers in the adjacent two-stage differential stretching mechanisms, so that the pole piece 1 is stretched.

The differential stretching module 300 can perform primary correction treatment on the wavy edge of the pole piece 1, and improve the wavy edge state of the pole piece 1, so as to facilitate the correction of the wavy edge of the pole piece 1 by the subsequent rolling module 100.

In some embodiments of the present application, as shown in fig. 4, the rolling device 1000 further includes a cold pressing module 400, and the cold pressing module 400 is used to provide the cold pressed pole piece 1 to the differential stretching module 300.

The cold press module 400 includes a cold press roller. The pole piece 1 is cold-pressed by adopting a rolling process. In the production process of the battery, the density of the electrode membrane in the pole piece 1 is lower after the electrode membrane is coated and dried by the slurry, and in order to improve the space utilization rate of the battery, the pole piece 1 with high energy density is obtained, and cold pressing is needed to be carried out on the pole piece 1. The cold pressing speed during cold pressing can be 5-50 m/min, the cold pressing pressure can be 0.5-100 MP, and the cold pressing gap can be 50-1 mm. The active substance of the pole piece 1 is tightly contacted with the current collecting piece by cold pressing, the thickness of the pole piece 1 is reduced, the filling amount is increased, and the utilization rate of the battery volume is improved, so that the capacity of the battery is improved.

In some embodiments of the present application, the rolling device 1000 includes a rolling module 100, a detecting module 200, a differential stretching module 300, and a cold pressing module 400. The rolling module 100 includes a press roller 10, a storage unit 20, and a control unit 30, wherein the control unit 30 is used for controlling the storage unit 20 to pump or inject fluid into the press roller 10, so that the press roller 10 is switched among a flat roller state, a concave roller state, and a convex roller state. Wherein the pole piece 1 comprises 3 film areas 2, the detection module 200 comprises 6 sets of encoding wheel sets 210 and an information processing unit 220. Wherein 3 groups of coding wheel sets 210 are arranged on 3 film areas 2 of the pole piece 1 in front of the press roller 10, and the other 3 groups of coding wheel sets 210 are arranged on 3 film areas 2 of the pole piece 1 behind the press roller 10. Wherein, each group of coding wheel sets 210 comprises at least 3 pairs of coding wheels 211, and each pair of coding wheels 211 comprises 2 coding wheels 211 respectively arranged at two sides of the pole piece 1.

Referring to fig. 6, fig. 6 is a schematic flow chart of a manufacturing method S1000 of a pole piece 1 according to a third aspect of the present application. The manufacturing method S1000 comprises providing the pole piece 1, providing the press roll 10 in any of the above embodiments and rolling the pole piece 1 using the press roll 10.

In some embodiments of the present application, the rolling method S1000 of the battery pole piece 1 further includes:

s10, providing a detection module 200, wherein the detection module 200 is used for detecting the extensibility of the pole piece 1;

s20, providing a rolling module 100, wherein the rolling module 100 is used for rolling the pole piece 1;

wherein the detection module 200 comprises a coding wheel set 210 and an information processing unit 220: the coding wheel set 210 is in contact with the pole piece 1 for detecting the extensibility of the pole piece 1; the information processing unit 220 is configured to collect the detection information of the encoding wheel set 210, process the detection information, and feed the processed detection information back to the control unit 30;

the roll-in module 100 includes the roll 10, the storage unit 20, and the control unit 30 in the above-described embodiments: the press roller 10 is used for rolling the pole piece 1; the storage unit 20 draws or injects fluid of the press roll layer 12 through the first liquid inlet opening towards the press roll 10; the control unit 30 is used for controlling the storage unit 20 to pump or inject fluid into the press roller 10, so that the press roller 10 is switched among a flat roller state, a concave roller state and a convex roller state;

optionally, the rolling method S1000 of the battery pole piece further includes:

s30, providing a pole piece 1, wherein the pole piece 1 comprises at least two film areas 2;

s40, providing a differential stretching module 300, wherein the differential stretching module 300 is used for carrying out primary stretching treatment on the pole piece 1 before the rolling of the press roller 10;

s50, providing a cold pressing module 400, wherein the cold pressing module 400 is used for providing the cold pressed pole piece 1 to the differential stretching module 300.

Optionally, the rolling method S1000 of the battery pole piece 1 further includes the following step S60:

s610, cold pressing the pole piece 1 by the cold pressing module 400;

s620, stretching the pole piece 1 by the differential stretching module 300 after cold pressing by the cold pressing module 400;

s630, detecting the extensibility of the pole piece 1 stretched by the differential stretching module 300 and rolled by the rolling module 100 by the coding wheel set 210 and feeding back to the information processing unit 220;

s640, the information processing unit 220 processes the feedback information of the coding wheel set 210 and feeds back the feedback information to the control unit 30;

s650, the control unit 30 controls the storage unit 20 to pump or inject fluid into the press roller 10 according to the feedback information of the information processing unit 220, so that the press roller 10 is in a flat roller state or a concave roller state or a convex roller state.

Optionally, S640 specifically includes the following steps:

s641, receiving and processing feedback information of a first coding wheel set (namely, a group of coding wheel sets 210 arranged on the surface of the pole piece 1 at the upstream of the press roller 10, and another group of coding wheel sets 210 arranged on the surface of the pole piece 1 at the downstream of the press roller 10): if the extensibility of the middle position of the film area 2 is high, the information processing unit 220 determines that the film area 2 has a wavy edge in the middle; if the edge position extensibility of the film area 2 is high, the information processing unit 220 determines that the edge of the film area 2 has a wavy edge; if the extension of the middle position and the extension of the edge position of the film region 2 are equal, the information processing unit 220 judges that the film region 2 is in a good state;

s642, the information processing unit 220 feeds back the determination of S641 to the control unit 30;

s643, the information processing unit 220 receives and processes feedback information of the second encoding wheel set (i.e. the group of encoding wheel sets 210 disposed on the surface of the pole piece 1 behind the press roller 10): if the extensibility of the middle position and the edge position of the film region 2 are not equal, the information processing unit 220 determines that the rolling effect of the rolling module 100 is insufficient; if the extensibility of the middle position and the edge position of the film region 2 are equal, the information processing unit 220 determines that the rolling effect of the rolling module 100 is good;

s644, the information processing unit feeds back the determination of S643 to the control unit 30.

Optionally, S650 specifically includes the following steps:

s651, receiving and processing judgment of S642: if the information processing unit 220 determines that the middle position of the film region 2 has a wavy edge, the control unit 30 controls the storage unit 20 to pump fluid to the press roller 10, so that the press roller 10 is in a concave roller state; if the information processing unit 220 determines that the edge position of the film region 2 has a wavy edge, the control unit 30 controls the storage unit 20 to inject fluid into the press roller 10, so that the press roller 10 is in a convex roller state; if the information processing unit 220 determines that the state of the film region 2 is good, the control unit 30 controls the storage unit 20 to inject or extract fluid into or from the press roller 10 so that the press roller 10 is in a flat roller state;

s652, receiving and processing the judgment of S644: if the information processing unit 220 determines that the rolling effect of the rolling module 100 is insufficient, the control unit 30 controls the storage unit 20 to draw or inject more fluid into the press roller 10 so that the outer diameter of the press roller 10 is changed; if the information processing unit 220 determines that the rolling effect of the rolling module 100 is good, the control unit 30 controls the pressing roller 10 to remain unchanged.

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

Claims

1. A pressure roller for rolling a pole piece of a battery, comprising:

a body portion having a channel for inputting or outputting a fluid;

the rolling layer is arranged on the outer side of the main body part and used for rolling the pole piece, a containing cavity is formed between the rolling layer and the outer surface of the main body part, and the containing cavity is communicated with the channel;

wherein the fluid is configured to flow into or out of the receiving cavity via the channel to deform the roll laminate;

the main body portion includes:

an inner column provided inside the main body;

the support column is used for supporting the roll-in layer, one end of the support column is connected with the inner column, and the other end of the support column is connected with the roll-in layer;

wherein the inner column, the support column and the roll lamination jointly enclose the accommodating cavity;

the channel comprises:

the first channel is arranged in the inner cavity of the inner column and extends along the axial direction of the inner column;

the second channel is arranged in the inner cavity of the support column and extends along the radial direction of the support column;

wherein the first channel is communicated with the second channel, the second channel is communicated with the accommodating cavity, and the fluid enters the accommodating cavity through the first channel and the second channel to squeeze the roll-in layer;

the support column includes first support column and the second support column of mutual separation, first support column is solid structure, the second passageway set up in the inner chamber of second support column.

2. A rolling device for pole pieces of a battery, characterized by comprising a rolling module comprising the press roller for rolling pole pieces of a battery according to claim 1, the press roller being for rolling the pole pieces.

3. The rolling device of the pole piece of the battery according to claim 2, wherein the rolling module further comprises:

a storage unit configured to store a fluid; and

a control unit for controlling the storage unit to pump or inject the fluid into the press roller.

4. A rolling device for pole pieces of a battery according to claim 3, further comprising a detection module for detecting the elongation of the pole piece and feeding back to the control unit.

5. The rolling device of the pole piece of the battery according to claim 4, wherein the detection module comprises:

the coding wheel set is used for contacting with the pole piece and detecting the extensibility of the pole piece; and

and the information processing unit is used for collecting the detection information of the coding wheel set and feeding back the detection information to the control unit after processing.

6. The rolling device of the battery pole piece according to claim 5, wherein the detection module comprises at least two groups of the coding wheel groups, one group of the coding wheel groups is arranged on the pole piece surface at the upstream of the press roller, and the other group of the coding wheel groups is arranged on the pole piece surface at the downstream of the press roller.

7. A manufacturing method of a pole piece is characterized in that:

providing a pole piece;

providing a press roll for rolling a pole piece of a battery according to claim 1;

and rolling the pole piece by using the press roller.