Internal stress removing device for battery pole piece
By combining a medium-containing box and an ultrasonic device, ultrasonic waves are conducted through a conductive medium to remove internal stress from the battery electrodes, thus solving the problem of easy cracking of the battery electrodes and improving their lifespan.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-07
- Publication Date
- 2026-03-27
AI Technical Summary
The battery electrodes are prone to cracking on the outer ring of the cell, which affects its lifespan.
A medium-containing box and an ultrasonic device are used to conduct ultrasonic waves through a conductive medium to perform high-frequency vibration treatment on the battery electrodes, thereby removing internal stress.
It effectively reduces internal stress in battery electrodes, improves the lifespan of battery electrodes, and avoids direct contact damage.
Smart Images
Figure CN224053138U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of battery pole piece processing, in particular to a battery pole piece internal stress removal device. BACKGROUND
[0002] The battery pole piece located at the outer circle of the battery cell is prone to cracking, reducing the service life of the battery pole piece.
[0003] The above statements are only used to provide background technical information related to the present application, and do not necessarily constitute the prior art. CONTENT OF THE UTILITY MODEL
[0004] The purpose of the present application is to provide a battery pole piece internal stress removal device, which aims to remove the internal stress of the battery pole piece to reduce the risk of cracking of the battery pole piece located at the outer circle of the battery cell.
[0005] The present application provides a battery pole piece internal stress removal device, comprising: a medium containing box configured to contain a conductive medium, comprising a pole piece inlet and a pole piece outlet; a pole piece conveying device configured to convey a battery pole piece, so that the battery pole piece enters the medium containing box through the pole piece inlet, and is output from the medium containing box after passing through the conductive medium through the pole piece outlet; and an ultrasonic device configured to emit ultrasonic waves, the ultrasonic waves being conducted to the battery pole piece through the conductive medium to at least partially eliminate the internal stress of the battery pole piece.
[0006] The battery pole piece internal stress removal device of the present application is provided with a medium containing box containing a conductive medium and an ultrasonic device, the battery pole piece is conveyed into the medium containing box by the pole piece conveying device, and the battery pole piece is at least partially in the conductive medium during the process of passing through the medium containing box, the ultrasonic waves emitted by the ultrasonic device can be uniformly and effectively conducted to the battery pole piece through the conductive medium, the battery pole piece is subjected to high-frequency vibration treatment, the internal stress of the battery pole piece is uniformly and effectively removed, which is beneficial to improve the stress removal effect of the battery pole piece and obtain a low-stress battery pole piece with uniform thickness; at the same time, the internal stress of the battery pole piece is removed in a non-contact manner, which is beneficial to reduce the damage that may be caused by directly applying ultrasonic waves to the battery pole piece; after the battery pole piece passes through the battery pole piece internal stress removal device, the internal stress is uniformly and effectively removed, the battery pole piece forms an electrode assembly with a separator and forms a battery cell, and the battery cell is assembled into a shell of a battery monomer to form a battery monomer, during the charge and discharge cycle of the battery monomer, the internal stress of the battery pole piece is relatively reduced, the thickness of the battery pole piece does not increase significantly, the expansion force of the battery cell is limited, and the expansion force of the battery pole piece at the outer circle of the battery cell and the force of the shell are effectively reduced, thereby improving the service life of the battery pole piece.
[0007] In some embodiments, the conductive medium is a gaseous medium with a density greater than that of air or a liquid medium.
[0008] The conductive medium is a gaseous medium with a density greater than that of air or a liquid medium, which is conducive to less attenuation of the ultrasonic wave in the process of the ultrasonic wave being conducted to the battery pole piece through the conductive medium, thereby, conducive to the ultrasonic wave being uniformly and effectively conducted to the battery pole piece to remove the internal stress of the battery pole piece more efficiently.
[0009] In some embodiments, the gaseous medium is carbon dioxide; or the liquid medium is an organic liquid medium or a lithium battery electrolyte.
[0010] The gaseous medium is carbon dioxide, which is conducive to removing the internal stress of the battery pole piece by the ultrasonic wave at a low cost, and the ultrasonic wave passing through the carbon dioxide does not cause damage to the battery pole piece, and the carbon dioxide, if escaping, has a slight impact on the environment.
[0011] The liquid medium is an organic liquid medium or a lithium battery electrolyte, which is conducive to the ultrasonic wave being uniformly and effectively conducted to the battery pole piece to remove the internal stress of the battery pole piece, and the ultrasonic wave passing through the organic liquid medium or the lithium battery electrolyte does not cause damage to the battery pole piece.
[0012] In some embodiments, the battery pole piece internal stress removal device further comprises a pressure adjusting device configured to place the gaseous medium in a negative pressure state.
[0013] The battery pole piece internal stress removal device further comprises a pressure adjusting device, which places the gaseous medium in a negative pressure state, which is conducive to preventing the gaseous medium from escaping from the medium containing box, on the one hand, to save the gaseous medium, and on the other hand, to prevent the gaseous medium from possibly having an adverse effect on the working environment of the battery pole piece internal stress removal device.
[0014] In some embodiments, the pressure adjusting device is configured to place the gaseous medium in a negative pressure range of -10 Pa to -2 Pa.
[0015] The negative pressure range of the gaseous medium is -10 Pa to -2 Pa, which can effectively reduce the gas in the working environment of the battery pole piece internal stress removal device from entering the medium containing box to affect the purity and density of the gaseous medium on the basis of preventing the gaseous medium from escaping from the medium containing box, which is conducive to the ultrasonic wave being effectively conducted to the battery pole piece to remove the internal stress of the battery pole piece more efficiently.
[0016] In some embodiments, the battery pole piece conveying device comprises a roller arranged in the medium containing box, the roller being configured to change the conveying direction of the battery pole piece in the medium containing box.
[0017] The battery pole piece conveying device is provided with a roller wheel for changing the conveying direction of the battery pole piece in the medium containing box, which is beneficial to make more parts of the battery pole piece in the medium containing box be in the conducting medium, improve the stress relief effect of the battery pole piece, and reduce the volume of the medium containing box.
[0018] In some embodiments, the battery pole piece conveying device comprises a plurality of roller wheels, which include an inlet roller near the pole piece inlet, an outlet roller near the pole piece outlet, and intermediate rollers between the inlet roller and the outlet roller; wherein the top edges of the inlet roller and the outlet roller are jointly on a first plane and the battery pole piece passes through the top edges of the inlet roller and the outlet roller, the bottom edges of at least one intermediate roller are spaced from the first plane and the battery pole piece passes through the bottom edges of the at least one intermediate roller; or the bottom edges of the inlet roller and the outlet roller are jointly on a first plane and the battery pole piece passes through the bottom edges of the inlet roller and the outlet roller, the top edges of at least one intermediate roller are spaced from the first plane and the battery pole piece passes through the top edges of the at least one intermediate roller.
[0019] By arranging the inlet roller, the outlet roller and the intermediate rollers, the conveying direction of the battery pole piece can be changed at the inlet, the outlet and the inside of the medium containing box, which is beneficial to make full use of the conducting medium contained in the medium containing box, improve the stress relief effect of the battery pole piece, and reduce the volume of the medium containing box.
[0020] In some embodiments, the top edges of the inlet roller and the outlet roller are jointly on the first plane, wherein the bottom edges of at least one intermediate roller are below the first plane; and / or the bottom edges of at least two intermediate rollers are jointly on a second plane parallel to the first plane.
[0021] The bottom edges of at least one intermediate roller are below the first plane, which is suitable for containing gaseous medium or liquid medium in the medium containing box, is beneficial to increase the length of the battery pole piece in the medium containing box to improve the stress relief effect of the battery pole piece and reduce the volume of the medium containing box; when containing liquid medium in the medium containing box, part of the battery pole piece is immersed in the liquid medium, so that the ultrasonic wave is effectively conducted to the battery pole piece through the liquid medium.
[0022] The bottom edges of at least two intermediate rollers are jointly on a second plane parallel to the first plane, which is beneficial to further increase the length of the battery pole piece in the conducting medium, thereby further improving the stress relief effect of the battery pole piece and reducing the volume of the medium containing box.
[0023] In some embodiments, the plurality of rollers comprises a plurality of intermediate rollers, the plurality of intermediate rollers comprises a first intermediate roller with a bottom edge on the second plane and a second intermediate roller with a top edge spaced from the second plane; wherein the first intermediate rollers and the second intermediate rollers are arranged alternately along the conveying direction of the battery pole piece; or the plurality of first intermediate rollers forms a plurality of intermediate roller groups, at least one intermediate roller group comprises two or more adjacent first intermediate rollers, and the intermediate roller groups and the second intermediate rollers are arranged alternately along the conveying direction of the battery pole piece.
[0024] The first intermediate rollers and the second intermediate rollers are arranged alternately along the conveying direction of the battery pole piece, which is conducive to changing the direction of the battery pole piece multiple times to increase the length of the battery pole piece in the medium containing box and the conductive medium, can more fully utilize the space of the medium containing box, is conducive to more effectively removing the internal stress of the battery pole piece and reducing the volume of the medium containing box.
[0025] The intermediate roller groups and the second intermediate rollers are arranged alternately along the conveying direction of the battery pole piece, and the two or more adjacent first intermediate rollers in the intermediate roller group are conducive to forming a horizontal conveying direction of the battery pole piece in the conductive medium, and are conducive to uniformly removing the internal stress of the battery pole piece.
[0026] In some embodiments, the bottom edge of at least part of the rollers is below the bottom edge of the pole piece inlet and the pole piece outlet.
[0027] The bottom edge of the rollers is below the bottom edge of the pole piece inlet and the pole piece outlet, which is suitable for the case that the battery pole piece is immersed in the liquid medium, and is conducive to the transmission of ultrasonic waves to the battery pole piece through the liquid medium to effectively remove the internal stress of the battery pole piece.
[0028] In some embodiments, the diameter of the rollers ranges from 50mm to 200mm.
[0029] The diameter of the rollers ranges from 50mm to 200mm, which is conducive to avoiding damage caused by increased stress due to turning of the battery pole piece, and is also conducive to reducing the excessive occupation of the internal space of the medium containing box for arranging the rollers.
[0030] In some embodiments, the ultrasonic device comprises a plurality of ultrasonic wave generators arranged symmetrically relative to the medium containing box; and / or the ultrasonic device comprises at least one ultrasonic wave generator arranged on the wall of the medium containing box.
[0031] The medium containing box is arranged with a plurality of ultrasonic wave generators, which is conducive to more uniformly removing the internal stress of the battery pole piece and improving the effect of removing the internal stress of the battery pole piece.
[0032] The ultrasonic generator is arranged on the wall of the medium accommodating box, which is beneficial to directly transmitting the ultrasonic wave to the conductive medium by the ultrasonic device, and is also beneficial to transmitting the ultrasonic wave to the medium after being partially conducted through the wall of the medium accommodating box, so that the ultrasonic wave is more uniformly conducted, and the effect of removing the internal stress of the battery tab is improved. In addition, no mounting bracket needs to be arranged for the ultrasonic device, and no internal space of the medium accommodating box needs to be occupied for arranging the mounting bracket.
[0033] In some embodiments, the medium accommodating box comprises a medium inlet for inputting the conductive medium and a medium outlet for outputting the conductive medium.
[0034] The medium accommodating box is provided with a medium inlet and a medium outlet, which is beneficial to supplementing or replacing the conductive medium according to the demand, and is also beneficial to maintaining the required pressure of the gaseous medium when the conductive medium is a gaseous medium.
[0035] In some embodiments, the battery tab internal stress removal device further comprises a thickness measuring device configured to measure the thickness information of the battery tab; and a control device connected with the thickness measuring device and connected with the ultrasonic device, and configured to control the working parameters of the ultrasonic device according to the thickness information.
[0036] The thickness measuring device is arranged to confirm the thickness of the battery tab. The control device is connected with the thickness measuring device and connected with the ultrasonic device, and the working parameters of the ultrasonic device are adjusted according to the measurement result of the thickness measuring device, that is, the thickness information of the battery tab which is easy to obtain is used to represent the demand of removing the internal stress of the battery tab, and the working parameters of the ultrasonic device are controlled according to the thickness information of the battery tab, so that the working parameters of the ultrasonic device can be more matched with the demand of removing the internal stress of the battery tab, thereby improving the effect of removing the internal stress of the battery tab and obtaining a low-stress battery tab with uniform thickness.
[0037] In some embodiments, the working parameters of the ultrasonic device include the power and frequency of the ultrasonic wave generator of the ultrasonic device.
[0038] The working parameters include the power and frequency of the ultrasonic wave generator, and the power and frequency of the ultrasonic wave generator are adjusted according to the measurement result of the thickness measuring device, which is beneficial to automatically adapting to the stress removal demand of the battery tab, and achieving the required stress removal effect of the battery tab while considering the reasonable energy consumption demand.
[0039] In some embodiments, the thickness measuring device comprises a first thickness measuring sensor and a second thickness measuring sensor, the first thickness measuring sensor is arranged upstream of the medium accommodating box along the conveying direction of the battery pole piece and is configured to measure a first pole piece thickness of the battery pole piece upstream of the medium accommodating box, the second thickness measuring sensor is arranged downstream of the medium accommodating box along the conveying direction of the battery pole piece and is configured to measure a second pole piece thickness of the battery pole piece downstream of the medium accommodating box; the control device controls the working parameter of the ultrasonic device according to the first pole piece thickness and the second pole piece thickness.
[0040] The first thickness measuring sensor and the second thickness measuring sensor respectively measure the first pole piece thickness before the battery pole piece enters the medium accommodating box and the second pole piece thickness after the battery pole piece is output from the medium accommodating box, and the control device controls the working parameter of the ultrasonic device according to the first pole piece thickness and the second pole piece thickness. The stress relief effect of the battery pole piece can be more accurately obtained through the first pole piece thickness and the second pole piece thickness, for example, the stress relief effect of the battery pole piece can be obtained by calculating the thickness difference or the thickness rebound ratio through the first pole piece thickness and the second pole piece thickness. Therefore, the real-time closed-loop adjustment of the stress relief of the battery pole piece is realized by controlling the working parameter of the ultrasonic device according to the first pole piece thickness and the second pole piece thickness, which is beneficial to the control device to control the working parameter of the ultrasonic device to match the stress relief demand of the battery pole piece, thereby improving the stress relief effect of the battery pole piece and obtaining a low-stress battery pole piece with uniform thickness.
[0041] In some embodiments, the first pole piece thickness and the second pole piece thickness are the first pole piece thickness and the second pole piece thickness of the same part of the battery pole piece.
[0042] The first pole piece thickness and the second pole piece thickness are the first pole piece thickness and the second pole piece thickness of the same part of the battery pole piece, which is beneficial to more accurately obtaining the stress relief effect of the battery pole piece, thereby further improving the stress relief effect of the battery pole piece through real-time closed-loop adjustment.
[0043] In some embodiments, the battery pole piece internal stress removal device further comprises: a cold rolling roller arranged upstream of the medium accommodating box along the conveying direction of the battery pole piece and configured to cold press the battery pole piece to be input into the pole piece inlet, the first thickness measuring sensor is arranged downstream of the cold rolling roller along the conveying direction of the battery pole piece to measure the first pole piece thickness of the battery pole piece cold pressed by the cold rolling roller; and / or a drying device arranged downstream of the medium accommodating box along the conveying direction of the battery pole piece and configured to dry the battery pole piece output from the pole piece outlet, the second thickness measuring sensor is arranged downstream of the drying device along the conveying direction of the battery pole piece to measure the second pole piece thickness of the battery pole piece dried by the drying device.
[0044] The first thickness measuring sensor is arranged downstream of the cold rolling roller in the conveying direction of the battery pole piece to measure the first pole piece thickness of the battery pole piece cold-pressed by the cold rolling roller, so as to obtain the first pole piece thickness under the condition that the internal stress of the battery pole piece is the largest, thereby facilitating more accurate obtaining of the stress relief effect of the battery pole piece, and further improving the stress relief effect of the battery pole piece through real-time closed-loop adjustment.
[0045] The second thickness measuring sensor is arranged downstream of the drying device in the conveying direction of the battery pole piece to measure the second pole piece thickness of the battery pole piece dried by the drying device, so as to prevent the residual liquid medium such as electrolyte from affecting the measurement result of the second thickness measuring sensor, thereby facilitating more accurate obtaining of the stress relief effect of the battery pole piece, and further improving the stress relief effect of the battery pole piece through real-time closed-loop adjustment.
[0046] The detailed description of the exemplary embodiments of the present application with reference to the accompanying drawings will be described below, and other features and advantages of the present application will become apparent. BRIEF DESCRIPTION OF DRAWINGS
[0047] The accompanying drawings, which are included to provide a further understanding of the present application, constitute a part of the present application, and the illustrative embodiments of the present application and their description serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings:
[0048] Figure 1 Structure schematic diagram of the battery pole piece internal stress removal device of some embodiments of the present application.
[0049] Figure 2 Control block diagram of the battery pole piece internal stress removal device of some embodiments of the present application.
[0050] Figure 3 Partial structure schematic diagram of the battery pole piece internal stress removal device of some other embodiments of the present application, in which the medium containing box and its related structures are shown.
[0051] Figure 4 Partial structure schematic diagram of the battery pole piece internal stress removal device of some other embodiments of the present application, in which the medium containing box and its related structures are shown.
[0052] Figures 1 to 4 In the drawings, the respective reference numerals represent:
[0053] E, battery pole piece;
[0054] M, conductive medium;
[0055] 1, medium containing box; 11, pole piece inlet; 12, pole piece outlet; 13, medium inlet; 14, medium outlet;
[0056] 2, pole piece conveying device; 21, roller; 211, inlet roller; 212, outlet roller; 213,
[0057] intermediate roller; 2131, first intermediate roller; 2132, second intermediate roller; 22, winding roller;
[0058] 3, ultrasonic device; 31, ultrasonic wave generator;
[0059] 4, thickness measuring device; 41, first thickness measuring sensor; 42, second thickness measuring sensor;
[0060] 5, control device;
[0061] 6, pressure adjusting device;
[0062] 7, cold rolling roller;
[0063] 8, drying device. DETAILED DESCRIPTION
[0064] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without any creative work, are within the scope of protection of the present application.
[0065] Unless otherwise specifically stated, the relative arrangement of parts, numerical expressions, and numerical values set forth in the embodiments are not intended to limit the scope of the present application. At the same time, it should be understood that, for the convenience of description, the sizes of the various parts shown in the drawings are not drawn in accordance with the actual proportional relationship. The technology, methods and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as part of the specification under appropriate circumstances. In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.
[0066] In the description of the application, it should be explained that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.
[0067] In the description of the application, it should be understood that the use of the terms "first", "second" and the like to qualify elements is merely intended to distinguish the corresponding elements, and unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the application.
[0068] In the description of the application, it should be understood that the orientation words such as "horizontal", "up", "down", "front", "back", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings, and are only used for the convenience of describing the application and simplifying the description. Unless otherwise stated, these orientation words do not indicate or imply that the devices or elements referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the application; the orientation words "inner" and "outer" refer to the inner and outer of the contour of each component.
[0069] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as they do not conflict with each other.
[0070] In the process of forming the technical scheme of the application, the inventors found that after the battery pole piece is cold-pressed, the coating is deformed, and the battery pole piece has a certain internal stress. In the case that the internal stress of the battery pole piece cannot be released, after the battery pole piece and the separator form an electrode assembly and form a battery cell, the battery cell is assembled into the shell of the battery monomer to form the battery monomer. During the charge and discharge cycle of the battery monomer, the release of the internal stress of the battery pole piece will be accelerated, the thickness of the battery pole piece will increase significantly, the swelling force of the battery cell will increase, and the battery pole piece at the outer circle of the battery cell will be affected by the swelling force and the force of the shell. Therefore, the battery pole piece at the outer circle of the battery cell is prone to cracking, thereby reducing the service life of the battery pole piece.
[0071] Based on this, the application provides a battery pole piece internal stress removal device, which comprises an ultrasonic device. The ultrasonic waves emitted by the ultrasonic device are transmitted to the battery pole piece through a conductive medium, so as to at least partially eliminate the internal stress of the battery pole piece. Since the internal stress of the battery pole piece is at least partially eliminated, during the charge and discharge cycle of the battery monomer comprising the battery pole piece, the increase in the thickness of the battery pole piece is relatively reduced, the swelling force of the battery cell is relatively reduced, and the cracking of the battery pole piece at the outer circle of the battery cell can be alleviated, thereby facilitating the improvement of the service life of the battery pole piece.
[0072] Battery pole piece is the core component of the electrode assembly constituting the battery cell. In this application, the battery cell can include lithium ion battery, sodium ion battery, sodium lithium ion battery, lithium metal battery, sodium metal battery, lithium sulfur battery, magnesium ion battery, nickel hydrogen battery, nickel cadmium battery, lead storage battery, etc. The present application does not limit this. The battery cell can be flat, cuboid or other shape, etc. The present application does not limit this. The battery cell is generally packaged as a square battery cell and a soft package battery cell, and the present application does not limit this.
[0073] The battery cell mainly includes electrode assembly and electrolyte, and the electrode assembly is mainly composed of positive pole piece, negative pole piece (the positive pole piece and the negative pole piece are collectively referred to as battery pole piece) and diaphragm. The battery cell can include one or more electrode assemblies. The battery cell mainly relies on the movement of metal ions between the positive pole piece and the negative pole piece to work. The positive pole piece includes a positive current collector and a positive active material coating, and the positive active material coating is coated on the surface of the positive current collector. The negative pole piece includes a negative current collector and a negative active material coating, and the negative active material coating is coated on the surface of the negative current collector.
[0074] As shown in Figures 1 to 4 The present application provides a battery pole piece internal stress removal device. The battery pole piece internal stress removal device includes a medium containing box 1, a pole piece conveying device 2 and an ultrasonic device 3. The medium containing box 1 is configured to contain the conductive medium M, including the pole piece inlet 11 and the pole piece outlet 12. The pole piece conveying device 2 is configured to convey the battery pole piece E, so that the battery pole piece E enters the medium containing box 1 through the pole piece inlet 11, and is output from the medium containing box 1 through the pole piece outlet 12 after passing through the conductive medium M. The ultrasonic device 3 is configured to emit ultrasonic waves, and make the ultrasonic waves conduct to the battery pole piece E through the conductive medium M, so as to at least partially eliminate the internal stress of the battery pole piece E.
[0075] The battery pole piece inner stress removal device of the application is provided with a medium containing box 1 containing the conducting medium M and an ultrasonic device 3. The battery pole piece E is conveyed into the medium containing box 1 by the pole piece conveying device 2, and the battery pole piece E is at least partially in the conducting medium M during the passing process in the medium containing box 1. The ultrasonic waves emitted by the ultrasonic device 3 can be uniformly and effectively conducted to the battery pole piece E through the conducting medium M. The battery pole piece E is subjected to high-frequency vibration treatment, and the inner stress of the battery pole piece E is uniformly and effectively removed, which is beneficial to improve the stress removal effect of the battery pole piece E and obtain a low-stress battery pole piece E with uniform thickness. At the same time, the inner stress of the battery pole piece E is removed in a non-contact manner, which is beneficial to reduce the damage that may be caused by directly applying ultrasonic waves to the battery pole piece E. After the battery pole piece E passes through the battery pole piece inner stress removal device, the inner stress is uniformly and effectively removed. After the battery pole piece E forms an electrode assembly with a separator and forms a battery cell, the battery cell is assembled into a shell of a battery monomer to form a battery monomer. During the charge and discharge cycle of the battery monomer, the inner stress release of the battery pole piece E is relatively reduced, the thickness of the battery pole piece E does not increase significantly, the expansion force of the battery cell is limited, and the expansion force and the force of the shell acting on the battery pole piece E at the outer circle of the battery cell are effectively reduced, thereby improving the service life of the battery pole piece E.
[0076] In some embodiments, as shown in Figure 1 、 Figure 3 and Figure 4 , the conducting medium M is a gaseous medium with a density greater than that of air or a liquid medium.
[0077] The conducting medium M is a gaseous medium with a density greater than that of air or a liquid medium, which is beneficial to reduce the attenuation of the ultrasonic waves during the process of conducting the ultrasonic waves to the battery pole piece E through the conducting medium M, thereby uniformly and effectively conducting the ultrasonic waves to the battery pole piece E to more efficiently remove the inner stress of the battery pole piece E.
[0078] In some embodiments, as shown in Figure 1 、 Figure 3 and Figure 4 , the gaseous medium is carbon dioxide; or the liquid medium is an organic liquid medium or a lithium battery electrolyte.
[0079] The gaseous medium is carbon dioxide, which is beneficial to remove the inner stress of the battery pole piece E by ultrasonic waves at a low cost, and the ultrasonic waves passing through carbon dioxide will not cause damage to the battery pole piece E, and the influence of the escaped carbon dioxide on the environment is slight.
[0080] The liquid medium is an organic liquid medium or a lithium battery electrolyte, which is beneficial to uniformly and effectively conduct the ultrasonic waves to the battery pole piece E to remove the inner stress of the battery pole piece E, and the ultrasonic waves passing through the organic liquid medium or the lithium battery electrolyte will not cause damage to the battery pole piece E.
[0081] In some embodiments, as shown in Figure 4 The battery electrode sheet internal stress removal device further comprises a pressure adjusting device 6 configured to place the gaseous medium in a negative pressure state.
[0082] The battery electrode sheet internal stress removal device further comprises a pressure adjusting device 6 configured to place the gaseous medium in a negative pressure state, which is conducive to preventing the gaseous medium from escaping from the medium containing box 1, on the one hand, it is conducive to saving the gaseous medium, on the other hand, it is conducive to preventing the gaseous medium from having an adverse effect on the working environment of the battery electrode sheet internal stress removal device.
[0083] In some embodiments, the pressure adjusting device 6 is configured to place the gaseous medium in a negative pressure range of -10 Pa to -2 Pa.
[0084] The negative pressure range of the gaseous medium is -10 Pa to -2 Pa, which can effectively reduce the gas in the working environment of the battery electrode sheet internal stress removal device from entering the medium containing box 1 and affecting the purity and density of the gaseous medium on the basis of preventing the gaseous medium from escaping from the medium containing box 1, which is conducive to the effective conduction of ultrasonic waves to the battery electrode sheet E to more efficiently remove the internal stress of the battery electrode sheet E.
[0085] In some embodiments, as shown in Figure 1 , Figures 3 to 4 The battery electrode sheet conveying device 2 comprises a roller 21 arranged in the medium containing box 1, and the roller 21 is configured to change the conveying direction of the battery electrode sheet E in the medium containing box 1.
[0086] The battery electrode sheet conveying device 2 is provided with the roller 21 for changing the conveying direction of the battery electrode sheet E in the medium containing box 1, which is conducive to making more parts of the battery electrode sheet E in the medium containing box 1 be in the conducting medium M, which is conducive to improving the stress removal effect of the battery electrode sheet E, and also conducive to reducing the volume of the medium containing box 1.
[0087] In some embodiments, as shown in Figure 1 , Figures 3 to 4 The battery electrode sheet conveying device 2 comprises a plurality of rollers 21, which include an inlet roller 211 close to the electrode sheet inlet 11, an outlet roller 212 close to the electrode sheet outlet 12, and an intermediate roller 213 between the inlet roller 211 and the outlet roller 212; wherein, as shown in Figure 1 , Figures 3 to 4As shown, the top edges of the inlet roller 211 and the outlet roller 212 are both on a first plane, and the battery electrode E passes through the top edges of the inlet roller 211 and the outlet roller 212. The bottom edge of at least one intermediate roller 213 is spaced from the first plane, and the battery electrode E passes through the bottom edge of at least one intermediate roller 213. Alternatively, in an embodiment not shown, the bottom edges of the inlet roller 211 and the outlet roller 212 are both on a first plane, and the battery electrode passes through the bottom edges of the inlet roller 211 and the outlet roller 212. The top edge of at least one intermediate roller 213 is spaced from the first plane, and the battery electrode passes through the top edge of at least one intermediate roller 213.
[0088] By setting inlet roller 211, outlet roller 212 and intermediate roller 213, the conveying direction of battery electrode E can be changed at the inlet, outlet and inside of the medium container 1, which is conducive to making fuller use of the conductive medium M contained in the medium container 1, improving the stress relief effect of battery electrode E and reducing the volume of the medium container 1.
[0089] In some embodiments, such as Figure 1 , Figures 3 to 4 As shown, the top edges of the inlet roller 211 and the outlet roller 212 are both on a first plane; wherein, the bottom edge of at least one intermediate roller 213 is located below the first plane; and / or the bottom edges of at least two intermediate rollers 213 are both on a second plane parallel to the first plane.
[0090] At least one intermediate roller 213 has its bottom edge located below the first plane, which is suitable for containing gaseous or liquid media in the medium receiving box 1. This facilitates the improvement of stress relief effect of battery electrode E by increasing the length of the battery electrode E located in the medium receiving box 1, thereby reducing the volume of the medium receiving box 1. When the medium receiving box 1 contains liquid media, it is beneficial for part of the battery electrode E to be immersed in the liquid media, thereby effectively realizing the transmission of ultrasonic waves to the battery electrode E through the liquid media.
[0091] The bottom edges of at least two intermediate rollers 213 are located on a second plane parallel to the first plane, which is conducive to further increasing the length of the battery electrode E in the conductive medium M, thereby further improving the stress relief effect of the battery electrode E and reducing the volume of the medium container 1.
[0092] In some embodiments, such as Figure 1 , Figures 3 to 4 As shown, the plurality of rollers 21 includes a plurality of intermediate rollers 213. The plurality of intermediate rollers 213 includes a first intermediate roller 2131 with its bottom edge on a second plane and a second intermediate roller 2132 with its top edge spaced from the second plane; wherein, as... Figure 1 and Figure 4 As shown, the first intermediate roller 2131 and the second intermediate roller 2132 are alternately arranged along the conveying direction of the battery electrode E; or as shown... Figure 3As shown, the plurality of first intermediate rollers 2131 form a plurality of intermediate roller groups, at least one intermediate roller group comprising two or more adjacent first intermediate rollers 2131, and the intermediate roller groups and the second intermediate rollers 2132 are arranged alternately along the conveying direction of the battery electrode sheet E.
[0093] The first intermediate rollers 2131 and the second intermediate rollers 2132 are arranged alternately along the conveying direction of the battery electrode sheet E, which is conducive to the multiple changes of direction of the battery electrode sheet E to increase the length of the battery electrode sheet E in the medium containing box 1 and the conducting medium M, so that the space of the medium containing box 1 can be more fully utilized, and the internal stress of the battery electrode sheet E can be more effectively removed and the volume of the medium containing box 1 can be reduced.
[0094] The intermediate roller groups and the second intermediate rollers 2132 are arranged alternately along the conveying direction of the battery electrode sheet E, and the two or more adjacent first intermediate rollers 2131 in the intermediate roller group are conducive to forming a horizontal conveying direction of the battery electrode sheet E in the conducting medium M, and conducive to uniformly removing the internal stress of the battery electrode sheet E.
[0095] In some embodiments, as shown in Figure 1 , Figures 3 to 4 At least part of the bottom edge of the roller 21 is located below the bottom edge of the electrode sheet inlet 11 and the electrode sheet outlet 12.
[0096] The bottom edge of the roller 21 located below the bottom edge of the electrode sheet inlet 11 and the electrode sheet outlet 12 is suitable for the case that the battery electrode sheet E is immersed in the liquid medium, which is conducive to the transmission of ultrasonic waves to the battery electrode sheet E through the liquid medium to effectively remove the internal stress of the battery electrode sheet E.
[0097] In some embodiments, as shown in Figure 1 , Figures 3 to 4 The diameter of the roller 21 ranges from 50 mm to 200 mm.
[0098] The diameter of the roller 21 ranging from 50 mm to 200 mm is conducive to avoiding damage caused by increased stress due to the turning of the battery electrode sheet E, and is also conducive to reducing the excessive occupation of the internal space of the medium containing box 1 for arranging the roller 21.
[0099] In some embodiments, as shown in Figure 1 , Figures 3 to 4 The ultrasonic device 3 comprises a plurality of ultrasonic wave generators 31 arranged symmetrically with respect to the medium containing box 1; and / or the ultrasonic device 3 comprises at least one ultrasonic wave generator 31 arranged on the wall of the medium containing box 1.
[0100] The medium containing box 1 is arranged with a plurality of ultrasonic wave generators 31 symmetrically, which is conducive to more uniformly removing the internal stress of the battery electrode sheet E and improving the effect of removing the internal stress of the battery electrode sheet E.
[0101] The ultrasonic generator 31 is arranged on the wall of the medium containing box 1, which is conducive to the ultrasonic device directly transmitting ultrasonic waves to the conductive medium M, and is also conducive to the ultrasonic waves being partially conducted through the wall of the medium containing box 1 and then being conducted to the medium M, so that the ultrasonic wave conduction is more uniform, and the effect of removing the internal stress of the battery tab E is improved. In addition, there is no need to arrange a mounting bracket for the ultrasonic device, and there is no need to occupy the internal space of the medium containing box 1 for arranging the mounting bracket.
[0102] In some embodiments, as shown in Figure 1 , Figures 3 to 4 The medium containing box 1 includes a medium inlet 13 for inputting the conductive medium M and a medium outlet 14 for outputting the conductive medium M.
[0103] The medium containing box 1 is provided with the medium inlet 13 and the medium outlet 14, which is conducive to supplementing or replacing the conductive medium M according to the needs, and is also conducive to maintaining the pressure required by the gaseous medium when the conductive medium M is a gaseous medium.
[0104] In some embodiments, as shown in Figure 1 and Figure 4 The battery tab internal stress removal device further includes a thickness measuring device 4 and a control device 5. The thickness measuring device 4 is configured to measure the thickness information of the battery tab E. The control device 5 is in signal connection with the thickness measuring device 4 and the ultrasonic device 3, and is configured to control the working parameters of the ultrasonic device 3 according to the thickness information.
[0105] The thickness measuring device 4 is arranged to confirm the thickness of the battery tab E. The control device 5 is in signal connection with the thickness measuring device 4 and the ultrasonic device 3, and adjusts the working parameters of the ultrasonic device 3 according to the measurement results of the thickness measuring device 4, that is, the thickness information of the battery tab E which is easy to obtain is used to represent the demand for removing the internal stress of the battery tab E, and the working parameters of the ultrasonic device 3 are controlled according to the thickness information of the battery tab E, so that the working parameters of the ultrasonic device 3 can be more matched with the demand for removing the internal stress of the battery tab E, thereby improving the effect of removing the internal stress of the battery tab E and obtaining a low-stress battery tab E with uniform thickness.
[0106] In some embodiments, the working parameters of the ultrasonic device 3 include the power and frequency of the ultrasonic generator 31 of the ultrasonic device 3.
[0107] The working parameters include the power and frequency of the ultrasonic generator 31, and the power and frequency of the ultrasonic generator 31 are adjusted through the measurement results of the thickness measuring device 4, which is conducive to automatically adapting to the stress removal demand of the battery tab E, and at the same time, the required stress removal effect of the battery tab E is realized while considering the reasonable energy consumption and other demands.
[0108] In some embodiments, as shown in Figure 1As shown, the thickness measuring device 4 includes a first thickness measuring sensor 41 and a second thickness measuring sensor 42, the first thickness measuring sensor 41 is arranged upstream of the medium containing box 1 along the conveying direction of the battery pole piece E and is configured to measure the first pole piece thickness of the battery pole piece E upstream of the medium containing box 1, the second thickness measuring sensor 42 is arranged downstream of the medium containing box 1 along the conveying direction of the battery pole piece E and is configured to measure the second pole piece thickness of the battery pole piece E downstream of the medium containing box 1; the control device 5 controls the working parameters of the ultrasonic device 3 according to the first pole piece thickness and the second pole piece thickness.
[0109] The first thickness measuring sensor 41 and the second thickness measuring sensor 42 respectively measure the pole piece thickness of the battery pole piece E before entering the medium containing box 1 and after being output from the medium containing box 1, and the control device 5 controls the working parameters of the ultrasonic device 3 according to the first pole piece thickness and the second pole piece thickness. The first pole piece thickness and the second pole piece thickness can be used to more accurately obtain the stress relief effect of the battery pole piece E. For example, the stress relief effect of the battery pole piece can be obtained by calculating the thickness difference or the thickness rebound ratio based on the first pole piece thickness and the second pole piece thickness. Therefore, controlling the working parameters of the ultrasonic device 3 according to the first pole piece thickness and the second pole piece thickness realizes real-time closed-loop adjustment of the stress relief of the battery pole piece E, which is beneficial to the control device 5 to control the working parameters of the ultrasonic device 3 to better match the stress relief demand of the battery pole piece E, thereby improving the stress relief effect of the battery pole piece E and obtaining a low-stress battery pole piece E with more uniform thickness.
[0110] In some embodiments, the first pole piece thickness and the second pole piece thickness are the first pole piece thickness and the second pole piece thickness of the same part of the battery pole piece E.
[0111] The first pole piece thickness and the second pole piece thickness are the first pole piece thickness and the second pole piece thickness of the same part of the battery pole piece E, which is beneficial to more accurately obtain the stress relief effect of the battery pole piece E, thereby further improving the stress relief effect of the battery pole piece E through real-time closed-loop adjustment.
[0112] In some embodiments, as shown, Figure 1 The battery pole piece internal stress removal device further includes a cold rolling roller 7 arranged upstream of the medium containing box 1 along the conveying direction of the battery pole piece E and configured to cold press the battery pole piece E to be input into the pole piece inlet 11, and the first thickness measuring sensor 41 is arranged downstream of the cold rolling roller 7 along the conveying direction of the battery pole piece E to measure the first pole piece thickness of the battery pole piece E cold pressed by the cold rolling roller 7; and / or a drying device 8 arranged downstream of the medium containing box 1 along the conveying direction of the battery pole piece E and configured to dry the battery pole piece E output from the pole piece outlet 12, and the second thickness measuring sensor 42 is arranged downstream of the drying device 8 for drying the battery pole piece E output from the pole piece outlet 12 along the conveying direction of the battery pole piece E to measure the second pole piece thickness of the battery pole piece E dried by the drying device 8.
[0113] The first thickness sensor 41 is positioned downstream of the cold rolling roll 7 along the conveying direction of the battery electrode E to measure the thickness of the first electrode of the battery electrode E cold-pressed by the cold rolling roll 7. This facilitates obtaining the thickness of the first electrode when the internal stress of the battery electrode E is at its maximum, thereby enabling a more accurate determination of the stress relief effect of the battery electrode E. Furthermore, the stress relief effect of the battery electrode E can be further improved through real-time closed-loop adjustment.
[0114] The second thickness sensor 42 is positioned downstream of the drying device 8 along the conveying direction of the battery electrode E to measure the thickness of the second electrode of the battery electrode E dried by the drying device 8. This helps to prevent residual liquid media such as electrolyte from affecting the measurement results of the second thickness sensor 42, thereby facilitating a more accurate acquisition of the stress relief effect of the battery electrode E. Furthermore, the stress relief effect of the battery electrode E can be further improved through real-time closed-loop adjustment.
[0115] The following is combined Figures 1 to 4 The battery electrode internal stress removal device of this application will be described in more detail.
[0116] exist Figure 1 and Figure 2 In the embodiment shown, the battery electrode internal stress removal device includes a dielectric container 1, an electrode conveying device 2, an ultrasonic device 3, a thickness measuring device 4, a control device 5, a pressure regulating device 6, a cold rolling roll 7, and a drying device 8.
[0117] The dielectric container 1 includes an electrode inlet 11, an electrode outlet 12, a dielectric inlet 13, and a dielectric outlet 14. The dielectric inlet 13 is located on the upper interior side of the dielectric container 1, and the dielectric outlet 14 is located on the lower interior side of the dielectric container 1. Electrolyte, serving as the conductive medium M, is filled into the dielectric container 1 through the dielectric inlet 13. In this embodiment, the electrode inlet 11 is located on the upper left side wall of the dielectric container 1, and the electrode outlet 12 is located on the upper right side wall of the dielectric container 1, with the electrode inlet 11 and electrode outlet 12 at the same height; the dielectric inlet 13 is located on the top wall of the dielectric container 1, and the dielectric outlet 14 is located on the bottom wall of the dielectric container 1.
[0118] The electrode conveying device 2 is used to convey battery electrodes E, allowing the battery electrodes E to enter the dielectric container 1 from the electrode inlet 11, pass through the electrolyte within, and exit from the electrode outlet 12. The electrode conveying device 2 includes multiple rollers 21 disposed within the dielectric container 1 and a take-up roller 22 located downstream of the dielectric container 1. The multiple rollers 21 have the same diameter, for example, 100 mm. The multiple rollers 21 include an inlet roller 211, multiple intermediate rollers 213, and an outlet roller 212. The first intermediate roller 2131 and the second intermediate roller 2132 are alternately arranged along the conveying direction of the battery electrodes E.
[0119] likeFigure 1 As shown, the inlet roller 211 and outlet roller 212 are positioned at the same height within the medium receiving tank 1. Three intermediate rollers 213 are two first intermediate rollers 2131 and one second intermediate roller 2132. One second intermediate roller 2132 is positioned at the same height as the inlet roller 211 and the outlet roller 212, while the two first intermediate rollers 2131 are positioned below them. The top edge of the first intermediate roller 2131 is on a first plane, the top edges of the inlet roller 211 and the outlet roller 212 are on a second plane, and both the first and second planes are horizontal. The electrode inlet 11 and the electrode outlet 12 are located on opposite side walls of the medium receiving tank 1. The heights of the electrode inlet 11 and the electrode outlet 12 are approximately equal to the height of the first plane. The electrolyte level is below the first plane where the top edges of the inlet roller 211 and the outlet roller 212 are located, for example, at the height of the center line of the inlet roller 211 and the outlet roller 212. Two first intermediate rollers 2131 are located below the electrolyte level. The two first intermediate rollers 2131 and one second intermediate roller 2132 are alternately arranged along the conveying direction of the battery electrode E.
[0120] The battery electrode E enters the medium container 1 from the electrode inlet 11, passes through the top edge of the inlet roller 211, the bottom edge of the first intermediate roller 2131, the top edge of the second intermediate roller 2132, the bottom edge of the second intermediate roller 2131, and the top edge of the outlet roller 212 in sequence, and then exits the medium container 1 from the electrode outlet 12.
[0121] The ultrasonic device 3 includes multiple ultrasonic generators 31. For example... Figure 1 As shown, the ultrasonic generator 31 comprises four ultrasonic generating components. Two of the four ultrasonic generators 31 are symmetrically arranged on the inner walls of the left and right sides of the media receiving tank 1, respectively. Specifically, two ultrasonic generators 31 are located on the left side wall (where the electrode inlet 11 is located) and the right side wall (where the electrode outlet 12 is located). The other two ultrasonic generators 31 are symmetrically arranged on the inner wall of the bottom wall of the media receiving tank 1, below the two first intermediate rollers 2131. The ultrasonic device 3 is installed away from the electrode inlet 11, electrode outlet 12, media inlet 13, and media outlet 14.
[0122] The ultrasonic generator 31 may include, for example, an electrical signal generating device, a transducer, and an amplitude transformer. The electrical signal generating device outputs a high-frequency electrical signal, the frequency and power of which are adjustable. The transducer converts the high-frequency electrical signal into mechanical vibration. The transducer is made of piezoelectric ceramic, and different frequencies and power of the high-frequency electrical signal result in different mechanical vibration frequencies and amplitudes of the transducer. The amplitude transformer amplifies the amplitude of the transducer, ensuring that the ultrasonic waves emitted by the ultrasonic generator 31 have sufficient energy to be transmitted through the conductive medium M to the battery electrode E.
[0123] like Figure 1 As shown, the thickness measuring device 4 includes a first thickness sensor 41 and a second thickness sensor 42. The first thickness sensor 41 and the second thickness sensor 42 can be, for example, a laser thickness gauge. Figure 2 As shown, the control device 5 is connected to the thickness measuring device 4 and the ultrasonic device 3 via signal transmission.
[0124] The cold rolling roll 7 is positioned upstream of the medium receiving box 1 along the conveying direction of the battery electrode E, and is configured to cold-press the battery electrode E to be input into the electrode inlet 11. The first thickness sensor 41 is positioned downstream of the cold rolling roll 7 along the conveying direction of the battery electrode E to measure the first electrode thickness of the battery electrode E cold-pressed by the cold rolling roll 7.
[0125] The drying device 8 is positioned downstream of the medium container 1 along the conveying direction of the battery electrode E, and is configured to dry the battery electrode E output from the electrode outlet 12. A second thickness sensor 42 is positioned downstream of the drying device 8 along the conveying direction of the battery electrode E to measure the second electrode thickness of the battery electrode E dried by the drying device 8. The drying device 8 may be, for example, an electric heating device, an oil heating device, or an infrared heating device.
[0126] The control device 5 controls the operating parameters of the ultrasonic device 3 based on the thickness of the first electrode and the thickness of the second electrode. The operating parameters of the ultrasonic device 3 include the power and frequency of the ultrasonic generator 31 of the ultrasonic device 3. Furthermore, the thickness of the first electrode and the thickness of the second electrode are the thicknesses of the first electrode and the second electrode at the same location on the battery electrode E.
[0127] During the stress relief process of battery electrode E, firstly, battery electrode E passes through cold rolling roll 7. After being cold-pressed, battery electrode E generates significant internal stress due to the deformation of the coating.
[0128] The first thickness sensor 41 measures the thickness of the first electrode sheet E after it has been cold-pressed by the cold rolling roller 7 and feeds the measurement result back to the control device 5.
[0129] The battery electrode E enters the medium container 1 from the electrode inlet 11, is guided and conveyed by an inlet roller 211, three intermediate rollers 213 and an outlet roller 212, and then leaves the medium container 1 from the electrode outlet 12. During the conveying process, the battery electrode E passes through the electrolyte.
[0130] When the battery pole piece E passes through the electrolyte, the ultrasonic waves emitted by each ultrasonic generator 31 can reach the battery pole piece E through the electrolyte to remove the internal stress of the battery pole piece E. The four ultrasonic generators 31 are all in signal connection with the control device 5.
[0131] After the battery pole piece E leaves the medium containing box 1 from the pole piece outlet 12, it passes through the drying device 8, which dries the electrolyte on the battery pole piece E.
[0132] The second thickness measuring sensor 42 measures the second pole piece thickness of the dried battery pole piece E and feeds back the measurement result to the control device 5. The control device 5 calculates the thickness rebound ratio in real time according to the first pole piece thickness and the second pole piece thickness of the same part of the battery pole piece E measured by the first thickness measuring sensor 41 and the second thickness measuring sensor 42 to adjust the power and frequency of the ultrasonic generator 31 of the ultrasonic device 3 in real time.
[0133] Finally, the winding roller 22 of the pole piece conveying device 2 winds the battery pole piece E whose internal stress has been removed.
[0134] As shown in the embodiment shown in Figure 3 The difference between the embodiment shown in Figure 1 and Figure 2 The main difference between the embodiment shown in Figure 1 The difference between the embodiment shown in
[0135] As shown in the embodiment shown in Figure 3 The difference between the embodiment shown in
[0136] The difference between the embodiment shown in Figure 3As shown, the plurality of intermediate rollers 213 includes four first intermediate rollers 2131 and one second intermediate roller 2132. Two first intermediate rollers 2131 form a group of intermediate rollers. The two first intermediate rollers 2131 of each group of intermediate rollers are arranged adjacently. The second intermediate roller 2132 is located between the two groups of intermediate rollers. The battery tab E enters the medium containing box 1 from the tab inlet 11, passes through the top edge of the inlet roller 211, the bottom edge of the two first intermediate rollers 2131 of the first group of intermediate rollers, the top edge of the second intermediate roller 2132, the bottom edge of the two first intermediate rollers 2131 of the second group of intermediate rollers, and the top edge of the outlet roller 212 in sequence, and then is output from the tab outlet 12 of the medium containing box 1.
[0137] In the medium containing box 1, two ultrasonic generators 31 are respectively arranged on the bottom wall of the medium containing box 1 at positions corresponding to the planes formed when the battery tab E passes through each group of intermediate rollers, and are arranged symmetrically left and right. Another two ultrasonic generators 31 are respectively arranged on the side wall of the medium containing box 1 where the tab inlet 11 is located and on the side wall of the medium containing box 1 where the tab outlet 12 is located, and are arranged symmetrically left and right, so as to remove the internal stress of the battery tab E.
[0138] Figure 3 The parts not described in the embodiment shown can refer to the related contents of Figure 1 and Figure 2 , which will not be described again here.
[0139] The embodiment shown in Figure 4 differs from the embodiments shown in Figure 1 and Figure 2 in that the medium containing box 1 is filled with carbon dioxide as a gaseous medium M, and a pressure adjusting device 6 is arranged at the upper part of the medium containing box 1. The pressure adjusting device 6 is used to maintain the gas negative pressure in the medium containing box 1. The pressure adjusting device 6 is, for example, a vacuum pump. In this embodiment, the medium inlet 13 is located on the bottom wall of the medium containing box 1, and the medium outlet 14 is located on the top wall of the medium containing box 1.
[0140] Figure 4 The parts not described in the embodiment shown can refer to the related contents of Figure 1 and Figure 2 , which will not be described again here.
[0141] In the embodiments not shown, various modifications can be made to the embodiments of the present application. For example, the number and arrangement position of the ultrasonic generators 31 of the ultrasonic device 3 can be changed. For example, the ultrasonic generators 31 can also be arranged on the top of the medium containing tank 1, or the ultrasonic generators 31 can also be arranged in the internal space of the medium containing tank 1 through a mounting bracket, the ultrasonic generators 31 can also be arranged on the outer side wall of the medium containing tank 1, and the like. For another example, the number and arrangement of the rollers 21 in the medium containing tank 1 can be changed. For example, in some modified examples of the embodiments shown in Figure 1 and Figure 4 more first intermediate rollers 2131 and second intermediate rollers 2132 can be included, in some modified examples of the embodiments shown in Figure 3 more intermediate roller groups and second intermediate rollers 2132 can be included. In addition, in some modified examples of the embodiments shown in Figures 1 to 4 the position of the second intermediate rollers 2132 can be lower than the inlet rollers 211 and the outlet rollers 212 or higher than the inlet rollers 211 and the outlet rollers 212, and the like. For another example, the shape, number, arrangement position, and the like of the medium inlet 13 and the medium outlet 14 of the medium containing tank 1 can also be set according to actual conditions.
[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application rather than limit the same; although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the specific embodiments of the present application can be modified or some technical features can be replaced by equivalent ones, which should be included in the technical solution range claimed by the present application.
Claims
1. A battery electrode sheet internal stress removal apparatus, characterized by, The battery electrode sheet internal stress removal device comprises: a medium containing box (1) configured to contain a conductive medium (M), comprising a pole piece inlet (11) and a pole piece outlet (12); a pole piece conveying device (2) configured to convey a battery electrode sheet (E) to make the battery electrode sheet (E) enter the medium containing box (1) through the pole piece inlet (11), and output the medium containing box (1) from the pole piece outlet (12) after passing through the conductive medium (M); and an ultrasonic device (3) configured to emit ultrasonic waves, which are conducted to the battery electrode sheet (E) through the conductive medium (M) to at least partially eliminate the internal stress of the battery electrode sheet (E).
2. The battery pole piece internal stress removal apparatus of claim 1, wherein, The conductive medium (M) is a gaseous medium with a density greater than that of air or a liquid medium.
3. The battery electrode sheet internal stress removal device according to claim 2, wherein the gaseous medium is carbon dioxide; or the liquid medium is an organic liquid medium or a lithium battery electrolyte.
4. The battery pole piece internal stress removal apparatus of claim 2, wherein, Further comprising a pressure regulating device (6) configured to make the gaseous medium in a negative pressure state.
5. The battery pole piece internal stress removal apparatus of claim 4, wherein, The pressure regulating device (6) is configured to make the negative pressure range of the gaseous medium be -10 Pa to -2 Pa.
6. The battery pole piece internal stress removal apparatus of claim 1, wherein, The battery electrode sheet conveying device (2) comprises a roller (21) arranged in the medium containing box (1), and the roller (21) is configured to change the conveying direction of the battery electrode sheet (E) in the medium containing box (1).
7. The battery pole piece internal stress removal apparatus of claim 6, wherein, The battery electrode sheet conveying device (2) comprises a plurality of rollers (21), which comprise an inlet roller (211) close to the pole piece inlet (11), an outlet roller (212) close to the pole piece outlet (12), and an intermediate roller (213) between the inlet roller (211) and the outlet roller (212); wherein the top edges of the inlet roller (211) and the outlet roller (212) are jointly on a first plane and the battery electrode sheet (E) passes through the top edges of the inlet roller (211) and the outlet roller (212), and the bottom edges of at least one intermediate roller (213) are spaced apart from the first plane and the battery electrode sheet (E) passes through the bottom edges of the at least one intermediate roller (213); or the bottom edges of the inlet roller (211) and the outlet roller (212) are jointly on a first plane and the battery electrode sheet (E) passes through the bottom edges of the inlet roller (211) and the outlet roller (212), and the top edges of at least one intermediate roller (213) are spaced apart from the first plane and the battery electrode sheet (E) passes through the top edges of the at least one intermediate roller (213).
8. The battery pole piece internal stress removal apparatus of claim 7, wherein, The top edges of the inlet roller (211) and the outlet roller (212) are jointly on the first plane, wherein the bottom edges of at least one intermediate roller (213) are below the first plane; and / or the bottom edges of at least two intermediate rollers (213) are jointly on a second plane parallel to the first plane.
9. The battery pole piece internal stress removal apparatus of claim 8, wherein, The plurality of rollers (21) comprises a plurality of intermediate rollers (213), the plurality of intermediate rollers (213) comprises a first intermediate roller (2131) with a bottom edge on the second plane and a second intermediate roller (2132) with a top edge spaced from the second plane; wherein, The first intermediate roller (2131) and the second intermediate roller (2132) are alternately arranged along the conveying direction of the battery pole piece (E); or A plurality of first intermediate rollers (2131) form a plurality of intermediate roller groups, at least one of the intermediate roller groups comprises two or more adjacent first intermediate rollers (2131), and the intermediate roller groups and the second intermediate rollers (2132) are alternately arranged along the conveying direction of the battery pole piece (E).
10. The battery pole piece internal stress removal apparatus of claim 6, wherein, The bottom edge of at least part of the rollers (21) is below the bottom edge of the pole piece inlet (11) and the pole piece outlet (12).
11. The battery pole piece internal stress removal apparatus of claim 6, wherein, The diameter of the roller (21) ranges from 50mm to 200mm.
12. The battery pole piece internal stress removal device according to claim 1, wherein, The ultrasonic device (3) comprises a plurality of ultrasonic generators (31) symmetrically arranged relative to the medium containing tank (1); and / or The ultrasonic device (3) comprises at least one ultrasonic generator (31) arranged on the tank wall of the medium containing tank (1).
13. The battery pole piece internal stress removal apparatus of claim 1, wherein, The medium containing tank (1) comprises a medium inlet (13) for inputting the conductive medium (M) and a medium outlet (14) for outputting the conductive medium (M).
14. The battery pole piece internal stress removal apparatus of any one of claims 1 to 13, wherein, Further comprising: A thickness measuring device (4) configured to measure thickness information of the battery pole piece (E); And A control device (5) in signal connection with the thickness measuring device (4) and in signal connection with the ultrasonic device (3), configured to control the working parameters of the ultrasonic device (3) according to the thickness information.
15. The battery pole piece internal stress removal apparatus of claim 14, wherein, The working parameters of the ultrasonic device (3) include the power and frequency of the ultrasonic generator (31) of the ultrasonic device (3).
16. The battery pole piece internal stress removal device according to claim 14, wherein, The thickness measuring device (4) comprises a first thickness measuring sensor (41) and a second thickness measuring sensor (42), the first thickness measuring sensor (41) is arranged upstream of the medium containing tank (1) along the conveying direction of the battery pole piece (E), and is configured to measure a first pole piece thickness of the battery pole piece (E) upstream of the medium containing tank (1), the second thickness measuring sensor (42) is arranged downstream of the medium containing tank (1) along the conveying direction of the battery pole piece (E), and is configured to measure a second pole piece thickness of the battery pole piece (E) downstream of the medium containing tank (1); The control device (5) controls the working parameters of the ultrasonic device (3) according to the first pole piece thickness and the second pole piece thickness.
17. The battery pole piece internal stress removal apparatus of claim 16, wherein, The first pole piece thickness and the second pole piece thickness are the first pole piece thickness and the second pole piece thickness of the same part of the battery pole piece (E).
18. The battery pole piece internal stress removal apparatus of claim 16, wherein, Further comprising: a cold rolling roller (7) disposed upstream of the medium containing box (1) in a conveying direction of the battery electrode sheet (E), configured to cold press the battery electrode sheet (E) to be input into the electrode sheet inlet (11), the first thickness measuring sensor (41) disposed downstream of the cold rolling roller (7) in the conveying direction of the battery electrode sheet (E) to measure the first electrode sheet thickness of the battery electrode sheet (E) cold pressed by the cold rolling roller (7); and / or a drying device (8) disposed downstream of the medium containing box (1) in the conveying direction of the battery electrode sheet (E), configured to dry the battery electrode sheet (E) output from the electrode sheet outlet (12), the second thickness measuring sensor (42) disposed downstream of the drying device (8) in the conveying direction of the battery electrode sheet (E) to measure the second electrode sheet thickness of the battery electrode sheet (E) dried by the drying device (8).