Pole piece cold pressing device and production equipment of electrode assembly

Abstract

The application relates to the technical field of batteries, and discloses a pole piece cold pressing device and a production equipment of an electrode assembly. The pole piece cold pressing device comprises a cold pressing roller set and a spraying assembly. The cold pressing roller set is provided with a first roller and a second roller arranged oppositely, and the first roller and the second roller define a roller pressing channel. The pole piece is adapted to pass through the roller pressing channel. The spraying assembly is arranged upstream of the cold pressing roller set and is used for performing gas spraying treatment on the surface of the pole piece and / or the surface of the first roller, so as to reduce the adhesion of the surface of the first roller and / or the surface of the pole piece. In this way, on one hand, the probability of roller adhesion can be reduced, and no additive or lubricating medium needs to be introduced, so that the pole piece quality, the consistency of the pole piece and the chemical stability of the battery can be improved, and the service life of the first roller can be prolonged; on the other hand, the gas spraying treatment and the cold pressing process can be continuously performed, the production efficiency can be improved, the compatibility is higher, and the modification cost of the existing device is lower.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to an electrode cold pressing device and an electrode assembly production equipment. Background Technology

[0002] In related technologies, in order to obtain the electrode thickness that meets the design requirements and improve the energy density of the battery, the electrode needs to be rolled. Rolling includes hot pressing and cold pressing. During the cold pressing process, sticking to the roller may occur, accompanied by peeling, deformation, and even electrode breakage. Utility Model Content

[0003] This application aims to at least solve one of the technical problems existing in the prior art. To this end, one objective of this application is to provide an electrode cold pressing device that can reduce the probability of roller sticking by performing gas spraying treatment on the electrode or cold pressing roller before the electrode passes through the roller, thereby reducing the probability of coating peeling, deformation, and strip breakage of the electrode and improving the processing yield.

[0004] This application further proposes a production equipment for an electrode assembly using the aforementioned electrode cold pressing device.

[0005] In a first aspect, this application provides an electrode cold pressing apparatus, comprising: a cold pressing roller group and a spraying assembly, the cold pressing roller group having a first roller and a second roller disposed opposite to each other, the first roller and the second roller defining a roller pressing channel, the electrode being adapted to pass through the roller pressing channel to compact the electrode, and the spraying assembly being disposed upstream of the cold pressing roller group and used to perform gas spraying treatment on the surface of the electrode and / or the surface of the first roller to reduce the stickiness of the surface of the first roller and / or the surface of the electrode.

[0006] According to the electrode cold pressing apparatus of this application embodiment, by setting a spraying component located upstream of the cold pressing roller group, on the one hand, the stickiness of the electrode surface or the surface of the first roller can be reduced, thereby reducing the probability of roller sticking, and no additives or lubricating media need to be introduced. This not only improves the quality of the electrode, enhances the consistency of the electrode and the chemical stability of the battery, but also extends the service life of the first roller. On the other hand, not only can the gas spraying treatment and cold pressing process be carried out continuously, which can improve production efficiency, but it also has higher compatibility and lower modification costs for existing devices.

[0007] According to some embodiments of this application, the spraying assembly includes: a gas supply section, a nozzle mounting plate, and a nozzle. The nozzle mounting plate has a gas receiving cavity. The gas supply section communicates with the gas receiving cavity, the nozzle communicates with the gas receiving cavity, and the nozzle is opposite to the surface of the electrode sheet and / or opposite to the surface of the first roller.

[0008] The above technical solution simplifies the structure of the spraying assembly, requiring only a gas source or a gas generating unit as a gas supply unit to supply gas to the nozzle. This further improves the compatibility of the spraying assembly and reduces the modification cost of the electrode cold pressing device.

[0009] According to some embodiments of this application, the length of the nozzle mounting plate is greater than or equal to the width of the electrode.

[0010] In the above technical solution, it can be ensured that the nozzle mounting plate can completely cover the electrode, so that the nozzle on the nozzle mounting plate can better cover the electrode, thereby improving the surface treatment effect after gas spraying, and making the active material in multiple areas in the width direction of the electrode less likely to stick to the roller.

[0011] According to some embodiments of this application, there are multiple nozzles, and the nozzles are spaced apart on the nozzle mounting plate along the length direction of the nozzle mounting plate.

[0012] In the above technical solution, by setting multiple nozzles and spacing them at intervals on the nozzle mounting plate, the uniformity of gas spraying can be improved, thereby enhancing the surface treatment effect of the electrode sheet or the first roller.

[0013] According to some embodiments of this application, among a plurality of nozzles, the center distance between the nozzles located at both ends of the length of the nozzle mounting plate is 100mm-2000mm.

[0014] In the above technical solution, by selecting a suitable nozzle mounting plate to adapt to the processing of electrode sheets of different widths, the compatibility and versatility of the coating assembly can be further improved.

[0015] According to some embodiments of this application, the distance between adjacent nozzles is 10mm-200mm.

[0016] In the above technical solution, based on different nozzle mounting plate lengths and different nozzle spraying ranges, the size interval of the nozzles can be reasonably set to make the distance between adjacent nozzles more reasonable, which can take into account the uniformity of spraying, reduce gas waste, and make the number of nozzles more reasonable, thereby reducing the cost of the spraying components and the overall cost of the electrode cold pressing device.

[0017] According to some embodiments of this application, the gas supply unit is configured as an ozone generator.

[0018] In the above technical solution, the microscopic interaction between the surface of the first roller and the surface of the electrode sheet can be achieved through ozone-induced hydrophilic-hydrophilic repulsion, thereby reducing the adhesion rate of the active material. Moreover, there is no need to stop the machine to clean the first roller. Ozone is eventually decomposed into oxygen, leaving no residual pollutants. This solution is suitable for continuous industrial production, conforms to the concept of green manufacturing, and helps to improve production efficiency.

[0019] According to some embodiments of this application, the gas supply unit is configured as a cryogenic gas pump, and the cryogenic gas is configured to be either nitrogen or carbon dioxide.

[0020] In the above technical solution, low-temperature gases, such as nitrogen and carbon dioxide, can be sprayed onto the surface of the first roller or the electrode sheet to reduce the surface temperature of the electrode sheet or the first roller, and also to reduce the surface adhesion of the first roller or the electrode sheet, thereby reducing the probability of roller sticking.

[0021] According to some embodiments of this application, the electrode cold pressing apparatus further includes: a surface treatment component, which is disposed on the periphery of the first roller, located upstream of the spraying component in the rotation direction of the first roller, and is used to perform surface treatment on the surface of the first roller upstream of the spraying component.

[0022] In the above technical solution, the surface of the first roller can be treated by the surface treatment component, which can reduce the amount of adhering substances on the surface of the first roller. Less adhering substances can improve the surface smoothness of the first roller, thereby reducing the probability of roller sticking. Of course, treating the surface of the first roller before gas spraying can also improve the gas spraying effect of the spraying component and further reduce the probability of roller sticking.

[0023] According to some embodiments of this application, the surface treatment assembly has a laser cleaning head for laser cleaning the surface of a first roller.

[0024] According to some embodiments of this application, the surface treatment assembly has a scraper for scraping the surface of the first roller.

[0025] In the above technical solution, the surface of the first roller can be cleaned by laser cleaning or scraping with a scraper before gas spraying. On the one hand, the surface cleaning of the first roller does not require stopping the machine and can be carried out continuously with the gas spraying and cold pressing processes, which can improve production efficiency. On the other hand, the smoother surface of the first roller can also reduce the probability of roller sticking.

[0026] Secondly, this application provides an electrode assembly manufacturing apparatus, including: the electrode cold pressing device in the above embodiments.

[0027] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0028] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the electrode sheet passing through the cold pressing roller assembly according to an embodiment of this application; Figure 2 This is a schematic diagram of the electrode cold pressing apparatus according to the first embodiment of this application; Figure 3 This is a schematic diagram of an electrode cold pressing apparatus according to the second embodiment of this application; Figure 4 This is a schematic diagram of an electrode cold pressing apparatus according to a third embodiment of this application; Figure 5 This is a schematic diagram of an electrode cold pressing apparatus according to the fourth embodiment of this application; Figure 6 This is a schematic diagram of an electrode cold pressing apparatus according to the fifth embodiment of this application; Figure 7 This is a schematic diagram of the fit between the nozzle mounting plate and the nozzle according to an embodiment of this application; Figure 8 This is a schematic diagram of a production equipment according to an embodiment of this application.

[0029] Figure label: Electrode cold pressing device 100, production equipment 200, electrode 300. Cold pressing roller assembly 10, first roller 11, second roller 12, roller pressing channel 13 Spraying assembly 20, gas supply unit 21, nozzle mounting plate 22, nozzle 23. Surface treatment component 30, The direction of electrode movement is X. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0032] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0033] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0035] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0036] In the description of this application, it should be understood that 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., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0037] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0038] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0039] In this application, "multiple" means two or more (including two).

[0040] A single battery cell can be a rechargeable battery. A rechargeable battery is a battery cell that can be recharged after it has been discharged, allowing the active materials to be activated and the cell to continue to be used.

[0041] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0042] In some embodiments, a battery cell may include a housing, an end cap, and an electrode assembly. The housing defines an accommodating space with an installation opening. The housing may be a pouch structure that wraps around the electrode assembly of a pouch battery, or it may be constructed as a rigid shell structure in which the electrode assembly is disposed.

[0043] The housing is a component used to fit with the end cap to form the internal environment of a battery cell. This internal environment can house electrode components, electrolyte, and other parts. The housing and end cap can be separate components. A mounting opening can be provided on the housing, and the end cap closes the opening at the mounting opening to form the internal environment of the battery cell. The housing can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc.

[0044] The housing may contain one or more electrode assemblies.

[0045] The electrode assembly is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly, while the portions without active material each constitute a tab. The positive and negative tabs can be located together at one end of the main body or at opposite ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals to form a current loop.

[0046] In some embodiments of this application, the positive electrode sheet includes a positive electrode active material. Optionally, the positive electrode sheet includes a positive electrode film layer containing the positive electrode active material. As an example, the positive electrode sheet also includes a positive electrode current collector, with the positive electrode film layer disposed on the positive electrode current collector; in another example, the positive electrode sheet is a self-supporting structure, comprising only the positive electrode film layer without a positive electrode current collector. Further, the positive electrode film layer also includes a conductive agent and a binder. In the positive electrode sheet, the conductive agent includes at least one of carbon black, graphite, carbon nanotubes (CNTs), graphene, and carbon fiber; the binder includes polyvinylidene fluoride (PVDF); the positive electrode current collector includes aluminum foil; and the positive electrode active material includes at least one of lithium iron phosphate, lithium manganese iron phosphate, lithium nickel manganese oxide, lithium cobalt oxide, lithium-rich manganese-based oxide, and lithium manganese oxide.

[0047] In some embodiments of this application, the negative electrode sheet includes a negative electrode active material. Optionally, the negative electrode sheet includes a negative electrode film layer containing the negative electrode active material. As an example, the negative electrode sheet also includes a negative electrode current collector, with the negative electrode film layer disposed on the negative electrode current collector; in another example, the negative electrode sheet is a self-supporting structure, comprising only the negative electrode film layer without a negative electrode current collector. Further, the negative electrode film layer also includes a conductive agent and a binder. In the negative electrode sheet, the conductive agent includes at least one of carbon black, graphite, carbon nanotubes (CNTs), graphene, and carbon fiber; the binder includes at least one of styrene-butadiene rubber (SBR) and polyacrylic acid (PAA); the negative electrode current collector includes copper foil; and the negative electrode active material includes at least one of carbon-based and silicon-based negative electrode materials. Optionally, the negative electrode active material includes lithium metal, and the negative electrode is a lithium metal negative electrode.

[0048] Currently, the conventional manufacturing process of electrode sheets (positive or negative electrode sheets) consists of multiple steps such as coating, drying, rolling, and slitting. Rolling is used to obtain the electrode sheet thickness that meets the design requirements in order to improve the energy density of the battery. Rolling includes cold pressing and hot pressing. In the actual cold pressing process, if the electrode sheet is designed to have a high forming density, it is easy for the rollers to stick together and peel off or deform during the cold pressing process. Existing methods to improve cold pressing roller sticking include: First, installing scrapers on both sides of the roller to scrape off the coating particles adhering to the roller, reducing the roughness of the roller surface. This only improves roller sticking to a certain extent, and the frequency of roller sticking will gradually increase as the pressing continues. Second, using a shutdown cleaning method during production, manually wiping with solvents such as deionized water or alcohol can achieve a certain cleaning effect, but this method is both time-consuming and may not be thorough. Third, applying a lubricating coating to the surface of the electrode sheet. During cold pressing, the lubricating coating reduces the peeling effect of the cold pressing roller on the electrode sheet, reducing the risk of roller sticking and strip breakage. However, the lubricating coating may affect the original active material components on the electrode sheet, even causing modification, and requires an additional lubricating coating application step, which will prolong the production cycle and reduce production efficiency.

[0049] In other words, in the relevant technologies, whether it is manual cleaning or scraping to remove the adhering substances on the roller surface, the improvement on roller sticking is relatively limited. Moreover, the high frequency of manual cleaning will affect production efficiency. While the method of using a lubricating coating has a stable and reliable effect in inhibiting roller sticking, there is a risk of modification of the active material, which will also affect production efficiency.

[0050] Based on this, this application proposes an electrode cold pressing device, which performs gas spraying treatment on the surface of the electrode or the surface of the first roller before the electrode enters the roller pressing channel by a spraying component. On the one hand, it can reduce the probability of roller sticking. On the other hand, it eliminates the need for manual cleaning and lubricating coating, which can not only improve production efficiency, but also reduce the probability of degradation and modification of the surface active material of the electrode, thereby improving the processing yield.

[0051] Below, in conjunction with Figures 1-6 The specific structure of the electrode cold pressing device 100 according to the embodiments of this application will be described.

[0052] like Figure 1As shown, the electrode cold pressing device 100 includes a cold pressing roller group 10, which includes a first roller 11 and a second roller 12. A roller pressing channel 13 is defined between the first roller 11 and the second roller 12. One of the first roller 11 and the second roller 12 rotates counterclockwise and the other rotates clockwise, so that the electrode 300 can pass through the roller pressing channel 13 along the electrode movement direction. During the process of the electrode 300 passing through the roller pressing channel 13, the electrode 300 is cold-pressed, and the active material attached to the electrode film layer (such as: positive electrode film layer, negative electrode film layer) is compacted.

[0053] It should be noted that, for ease of understanding of the technical solution, this application introduces the concepts of upstream and downstream. During the process of the electrode 300 flowing in the electrode cold pressing device 100, the area that the electrode 300 passes through first in the direction of electrode movement is defined as upstream, and the area that the electrode 300 passes through later is defined as downstream. Similarly, during the rotation of the first roller 11 and the second roller 12, the area that the first roller 11 or the second roller 12 passes through first is defined as upstream, and the area that it passes through later is defined as downstream. For example, if the first roller 11 passes through the surface treatment component 30 first and then the spraying component 20, then the spraying component 20 is located downstream of the surface treatment component 30. If the electrode 300 passes through the spraying component 20 first and then the roller pressing channel 13, then the spraying component 20 is located upstream of the cold pressing roller group 10.

[0054] like Figure 2 As shown, in the first embodiment, the electrode cold pressing device 100 includes: a cold pressing roller group 10 and a spraying assembly 20. The spraying assembly 20 includes: a gas supply unit 21, a nozzle mounting plate 22 and a nozzle 23.

[0055] The spraying assembly 20 is located upstream of the cold press roller group 10. The spraying assembly 20 is used to perform gas spraying treatment on the surface of the electrode 300, that is, the nozzle 23 faces the surface of the electrode 300.

[0056] like Figure 3 As shown, in the second embodiment, the electrode cold pressing device 100 includes: a cold pressing roller group 10 and a spraying assembly 20. The spraying assembly 20 includes: a gas supply unit 21, a nozzle mounting plate 22 and a nozzle 23.

[0057] The spraying assembly 20 is located upstream of the cold press roller group 10. The spraying assembly 20 is used to perform gas spraying treatment on the surface of the first roller 11, that is, the nozzle 23 faces the surface of the first roller 11.

[0058] like Figure 4 As shown, in the third embodiment, the electrode cold pressing device 100 includes: a cold pressing roller group 10 and a spraying assembly 20. The spraying assembly 20 includes: a gas supply unit 21, a nozzle mounting plate 22 and a nozzle 23.

[0059] The spraying assembly 20 is located upstream of the cold press roller group 10. The spraying assembly 20 is used to perform gas spraying treatment on the surface of the first roller 11 and the surface of the electrode 300. That is, there are two sets of nozzles 23, one set facing the surface of the first roller 11 and the other set facing the surface of the electrode 300.

[0060] like Figure 5 As shown, in the fourth embodiment, the electrode cold pressing device 100 includes: a cold pressing roller group 10, a spraying assembly 20 and a surface treatment assembly 30. The spraying assembly 20 includes: a gas supply unit 21, a nozzle mounting plate 22 and a nozzle 23. The surface treatment assembly 30 has a laser cleaning head.

[0061] The spraying assembly 20 is located upstream of the cold pressing roller group 10, and the surface treatment assembly 30 is located upstream of the spraying assembly 20. The spraying assembly 20 is used to perform gas spraying treatment on the surface of the electrode 300, that is, the nozzle 23 faces the surface of the electrode 300. The surface treatment assembly 30 is used to perform laser cleaning on the surface of the first roller 11 before the spraying assembly 20, so as to improve the surface smoothness of the first roller 11.

[0062] like Figure 6 As shown, in the fifth embodiment, the electrode cold pressing device 100 includes: a cold pressing roller group 10, a spraying assembly 20 and a surface treatment assembly 30. The spraying assembly 20 includes: a gas supply unit 21, a nozzle mounting plate 22 and a nozzle 23. The surface treatment assembly 30 has a scraper.

[0063] The spraying assembly 20 is located upstream of the cold press roller group 10, and the surface treatment assembly 30 is located upstream of the spraying assembly 20. The spraying assembly 20 is used to perform gas spraying treatment on the surface of the electrode 300, that is, the nozzle 23 faces the surface of the electrode 300. The scraper is used to remove the adhering substances on the surface of the first roller 11 in front of the spraying assembly 20, so as to improve the surface smoothness of the first roller 11.

[0064] It should be noted that the second embodiment differs from the first embodiment in that the nozzles 23 point in different directions. The third embodiment differs from the first embodiment in that two sets of nozzles 23 are provided, and the two sets of nozzles 23 act on the surfaces of the first roller 11 and the electrode 300 respectively. The fourth embodiment differs from the first embodiment in that a surface treatment component 30 is further provided. The fifth embodiment differs from the first embodiment in that a surface treatment component 30 is further provided, and the nozzles 23 point in different directions.

[0065] The following is for reference. Figures 1-8 This application describes an electrode cold pressing apparatus 100 and an electrode assembly production equipment 200 according to embodiments of the present application.

[0066] like Figures 1-6As shown, this application provides an electrode cold pressing device 100, including: a cold pressing roller group 10 and a spraying assembly 20.

[0067] The cold pressing roller group 10 has a first roller 11 and a second roller 12 arranged opposite to each other. The first roller 11 and the second roller 12 define a roller pressing channel 13. The electrode 300 is adapted to pass through the roller pressing channel 13 to compact the electrode 300. The spraying assembly 20 is arranged upstream of the cold pressing roller group 10 and is used to perform gas spraying treatment on the surface of the electrode 300 and / or the surface of the first roller 11 to reduce the stickiness of the surface of the first roller 11 and / or the surface of the electrode 300.

[0068] It should be noted that the spraying assembly 20 being located upstream of the cold pressing roller group 10 means that the electrode 300 first passes through the spraying assembly 20 and then through the roller pressing channel 13 of the cold pressing roller group 10. The purpose of using the spraying assembly 20 to perform gas spraying treatment on the surface of the electrode 300 and / or the surface of the first roller 11 means that, in some embodiments, the spraying assembly 20 is used to perform gas spraying treatment on the surface of the electrode 300; in some embodiments, the spraying assembly 20 is used to perform gas spraying treatment on the surface of the first roller 11; and in some embodiments, the spraying assembly 20 performs gas spraying treatment on both the surface of the electrode 300 and the surface of the first roller 11 simultaneously.

[0069] It is understood that the first roller 11 refers to the cold pressing roller that contacts the active material layer on the electrode 300 when the electrode 300 passes through the roller pressing channel 13, and the second roller 12 refers to the cold pressing roller that presses against the side of the electrode 300 that does not have active material when the electrode 300 passes through the roller pressing channel 13. The two have the same structure, and the surface smoothness of the second roller 12 is greater than or equal to the surface smoothness of the first roller 11.

[0070] Specifically, before the electrode 300 passes through the roller pressing channel 13, at least one of the surfaces of the electrode 300 and the first roller 11 is subjected to gas spraying treatment by the spraying assembly 20. The gas spraying treatment can reduce the stickiness of the surface of the electrode 300 or the surface of the first roller 11, thereby reducing the probability of roller sticking.

[0071] Understandably, because the surface of the first roller 11 or the electrode 300 has lower adhesion, the sticking to the roller is reduced, allowing the surface of the first roller 11 to be pressed more evenly during the cold pressing process. This improves the flatness of the electrode 300 surface, reduces surface defects such as micropores and cracks, lowers the risk of active material peeling and strip breakage, and improves the quality of the electrode 300, thereby enhancing the consistency and electrochemical performance of the battery.

[0072] Of course, it can also extend the service life of the first roller 11, that is, reduce roller sticking, reduce wear and scratches on the surface of the first roller 11, reduce the frequency and probability of wear and scratches, thereby extending the service life of the first roller 11 and reducing the maintenance frequency and maintenance cost of the electrode cold pressing device 100.

[0073] It should be noted that during the conveyor belt process of electrode 300, surface gas spraying treatment is performed first, followed by cold pressing of electrode 300. This allows for continuous processing, and the gas spraying treatment and cold pressing process can be carried out continuously, which is suitable for industrial production needs. There is no need to stop the machine for manual cleaning of the surface of the first roller 11, which can improve production efficiency. Furthermore, surface treatment by spraying gas can also achieve pollution-free operation.

[0074] Furthermore, there is no need to coat the surface of the electrode 300 with a lubricating coating, and no need to introduce external lubricants or additives. That is, it does not rely on external chemical additives (such as silicone oil, zinc stearate, etc.), which can avoid the negative impact of impurities on the active material and avoid the modification or deterioration of the active material caused by the introduction of impurities.

[0075] Of course, the electrode cold pressing device 100 of this application can be directly applied to the existing electrode cold pressing device 100 by setting the spraying component 20 upstream of the cold pressing roller group 10, which has high compatibility and low modification cost.

[0076] According to the embodiment of this application, the electrode cold pressing apparatus 100, by setting a spraying component 20 located upstream of the cold pressing roller group 10, can reduce the stickiness of the surface of the electrode 300 or the surface of the first roller 11, thereby reducing the probability of roller sticking, and without the need to introduce additives or lubricating media, not only can it improve the quality of the electrode 300, enhance the consistency of the electrode 300 and the chemical stability of the battery, but it can also extend the service life of the first roller 11; on the other hand, not only can the gas spraying treatment and cold pressing process be carried out continuously, which can improve production efficiency, but it also has higher compatibility and lower modification cost of existing equipment.

[0077] Combination Figures 2-6 As shown, according to some embodiments of this application, the spraying assembly 20 includes: a gas supply section 21, a nozzle mounting plate 22, and a nozzle 23. The nozzle mounting plate 22 is provided with a gas receiving cavity. The gas supply section 21 is connected to the gas receiving cavity. The nozzle 23 is connected to the gas receiving cavity. The nozzle 23 is opposite to the surface of the electrode 300 and / or the nozzle 23 is opposite to the surface of the first roller 11.

[0078] Specifically, the gas supply unit 21 is used to supply gas to the gas receiving cavity, and the nozzle mounting plate 22 is equipped with a nozzle 23 so that the nozzle 23 can perform gas spraying toward the surface of the electrode 300 or the surface of the first roller 11.

[0079] This simplifies the structure of the spraying assembly 20, requiring only one gas source or one gas generating unit as the gas supply unit 21 to supply gas to the nozzle 23. This further improves the compatibility of the spraying assembly 20 and reduces the modification cost of the electrode cold pressing device 100.

[0080] According to some embodiments of this application, the length of the nozzle mounting plate 22 is greater than or equal to the width of the electrode 300.

[0081] This ensures that the nozzle mounting plate 22 can completely cover the electrode 300, so that the nozzle 23 on the nozzle mounting plate 22 can better cover the electrode 300, thereby improving the surface treatment effect after gas spraying and reducing the probability of the active material sticking to the roller in multiple areas of the electrode 300 in its width direction.

[0082] like Figure 7 As shown, according to some embodiments of this application, there are multiple nozzles 23, and the nozzles 23 are spaced apart on the nozzle mounting plate 22 along the length direction of the nozzle mounting plate 22.

[0083] Therefore, by setting multiple nozzles 23 and arranging them at intervals on the nozzle mounting plate 22, the uniformity of gas spraying can be improved, thereby enhancing the surface treatment effect of the electrode 300 or the first roller 11.

[0084] According to some embodiments of this application, among the plurality of nozzles 23, the center distance between the nozzles 23 located at both ends of the length of the nozzle mounting plate 22 is 100mm-2000mm.

[0085] For example, the center distance between the nozzles 23 located at both ends of the length of the nozzle mounting plate 22 is 100mm, 200mm, 260mm, 330mm, 420mm, 550mm, 600mm, 1000mm, 1750mm, 2000mm, etc.

[0086] In this way, by selecting a suitable nozzle mounting plate 22 to adapt to the processing of electrode sheets 300 with different widths, the compatibility and versatility of the spraying assembly 20 can be further improved.

[0087] Furthermore, the distance between adjacent nozzles 23 is 10mm-200mm.

[0088] For example, the distance between adjacent nozzles 23 is 10mm, 19mm, 25mm, 30mm, 45mm, 90mm, 100mm, 145mm, 190mm, 200mm, etc.

[0089] In this way, based on the different lengths of the nozzle mounting plate 22 and the different spraying ranges of the nozzles 23, the size interval of the nozzles 23 can be reasonably set, making the distance between adjacent nozzles 23 more reasonable, which can take into account the uniformity of spraying, reduce gas waste, and make the number of nozzles 23 more reasonable, thereby reducing the cost of the spraying assembly 20 and the overall cost of the electrode cold pressing device 100.

[0090] In some embodiments, the gas supply unit 21 may be configured as an ozone generator (i.e., a gas generating unit).

[0091] Specifically, during the cold pressing process, ozone acts on the surface of the first roller 11 or the electrode 300, inducing the formation of hydrophilic functional groups (such as -OH, -O-) on the surface of the first roller 11 or the electrode 300, thereby enhancing the hydrophilicity of the surface of the first roller 11 or the electrode 300. By forming a stable hydrophilic layer on the surface of the first roller 11 or the electrode 300, a repulsive effect is formed between the surface of the first roller 11 and the surface of the electrode 300 (repulsive effect between hydrophilic layers), which can reduce viscosity and thus reduce the phenomenon of roller sticking during the cold pressing process.

[0092] Thus, through the ozone-induced hydrophilic-hydrophilic repulsion, the microscopic interaction between the surface of the first roller 11 and the surface of the electrode 300 is achieved, thereby reducing the adhesion rate of the active material. Moreover, there is no need to stop the machine to clean the first roller 11. The ozone is eventually decomposed into oxygen, leaving no residual pollutants. This method is suitable for continuous industrial production, conforms to the concept of green manufacturing, and helps to improve production efficiency.

[0093] Of course, the gas spraying process in this application embodiment is not limited to ozone spraying. In other embodiments, the gas supply unit 21 is configured as a cryogenic gas pump (i.e., gas source), and the cryogenic gas is configured as either nitrogen or carbon dioxide.

[0094] In other words, by spraying low-temperature gases, such as nitrogen or carbon dioxide, onto the surface of the first roller 11 or the electrode 300, the surface temperature of the electrode 300 or the first roller 11 can be reduced, as can the surface adhesion of the first roller 11 or the electrode 300, thereby reducing the probability of roller sticking.

[0095] like Figure 5 and Figure 6 As shown, according to some embodiments of this application, the electrode cold pressing apparatus 100 further includes a surface treatment component 30, which is disposed on the periphery of the first roller 11. The surface treatment component 30 is located upstream of the spraying component 20 in the rotation direction of the first roller 11 and is used to perform surface treatment on the surface of the first roller 11 upstream of the spraying component 20.

[0096] The fact that the surface treatment component 30 is located upstream of the spraying component 20 in the rotation direction of the first roller 11 means that the area of ​​the electrode 300 that the first roller 11 is about to act on will first pass through the surface treatment component 30, then through the spraying component 20, and then through the roller pressing channel 13.

[0097] In this way, the surface of the first roller 11 can be treated by the surface treatment component 30, which can reduce the amount of deposits on the surface of the first roller 11. Fewer deposits can improve the surface smoothness of the first roller 11, thus reducing the probability of roller sticking. Of course, if the surface of the first roller 11 is treated before gas spraying, in the embodiment where the spraying component 20 acts on the surface of the first roller 11, the gas spraying treatment effect of the spraying component 20 can also be improved, further reducing the probability of roller sticking.

[0098] It should be noted that in some embodiments, the surface treatment component 30 has a laser cleaning head for laser cleaning the surface of the first roller 11, and in other embodiments, the surface treatment component 30 has a scraper for scraping the surface of the first roller 11.

[0099] In this way, the surface of the first roller 11 can be cleaned by laser cleaning or scraping with a scraper before gas spraying. On the one hand, the surface cleaning of the first roller 11 does not require stopping the machine and can be carried out continuously with the gas spraying and cold pressing processes, which can improve production efficiency. On the other hand, the smoother surface of the first roller 11 can also reduce the probability of roller sticking.

[0100] For example: In a specific embodiment where the gas supply unit 21 is configured as an ozone generator, the nozzle 23 acts on the surface of the first roller 11, and the electrode 300 is an anode electrode 300, during the cold pressing process, ozone ions are sprayed onto the surface of the first roller 11 through the ozone generator. The ozone ions bombard the surface of the first roller 11, generating hydrophilic groups, which reduces the adhesion tendency between the surface of the first roller 11 and the anode active material. The anode active material can be silicon, graphite, or a composite material thereof.

[0101] Specifically, the ozone generator sprays ozone ions onto the surface of the first roller 11 through nozzle 23. The material of the first roller 11 is stainless steel, tungsten carbide, chrome-plated material, etc. By reasonably adjusting the ozone concentration, spray frequency and cold pressing parameters, the surface of the first roller 11 is treated with ozone, and the hydrophilicity is improved to a contact angle of <30°, which can effectively reduce stickiness and reduce the probability of roller sticking.

[0102] The parameters that need to be adjusted include, but are not limited to: ozone concentration of 0.5ppm-10ppm, spray frequency of 10Hz; cold pressing parameters: pressure of 60t-80t, speed of 20m / min-80m / min; particle size of anode active material of 50μm, and no obvious adhering particles on the surface of the first roller 11 after cold pressing.

[0103] In an embodiment where the gas supply unit 21 is configured as an ozone generator, the nozzle 23 acts on the surface of the first roller 11, the electrode 300 is an anode electrode 300, and a surface treatment component 30 is further configured, the surface treatment component 30 having a laser cleaning head, during the cold pressing process, ozone ions are sprayed onto the surface of the first roller 11 through the ozone generator. The ozone ions bombard the surface of the first roller 11, generating hydrophilic groups, reducing the adhesion tendency between the surface of the first roller 11 and the anode active material. The anode active material can be silicon, graphite or their composite materials.

[0104] The ozone generator sprays ozone ions onto the surface of the first roller 11 through nozzle 23. The first roller 11 is made of materials such as stainless steel, tungsten carbide, and chrome-plated materials. By reasonably adjusting the ozone concentration, spray frequency, and cold pressing parameters, the surface of the first roller 11 is treated with ozone, and the hydrophilicity is improved to a contact angle of <30°, which can effectively reduce stickiness and reduce the probability of roller sticking.

[0105] The parameters that need to be adjusted include, but are not limited to: ozone concentration of 0.5ppm-10ppm, spray frequency of 10Hz; cold pressing parameters: pressure of 60t-80t, speed of 20m / min-80m / min; particle size of anode active material of 50μm, and no obvious adhering particles on the surface of the first roller 11 after cold pressing.

[0106] Furthermore, the surface treatment component 30 can remove the organic and inorganic substances (attachments) adhering to the surface of the first roller 11 by laser burning, restore the original flatness of the surface of the first roller 11, expose the original roller material, and rotate further, and the surface of the first roller 11 is sprayed with ozone.

[0107] In this way, with the synergistic effect of the surface treatment components 30, the cleanliness and smoothness of the surface of the first roller 11 can be improved, the ozone spraying efficiency can be improved, and thus the modification effect of ozone on the surface of the first roller 11 can be improved.

[0108] In an embodiment where the gas supply unit 21 is configured as an ozone generator and the nozzle 23 acts on the surface of the electrode 300, and the electrode 300 is an anode electrode 300, during the cold pressing process, ozone ions are sprayed onto the surface of the electrode 300 through the ozone generator. The ozone ions bombard the surface of the electrode 300, generating hydrophilic groups and reducing the adhesion tendency between the surface of the electrode 300 and the anode active material. The anode active material can be silicon, graphite, or a composite material thereof.

[0109] Specifically, the ozone generator sprays ozone ions onto the surface of the electrode 300 through nozzle 23. The material of the first roller 11 is stainless steel, tungsten carbide, chrome-plated material, etc. By reasonably adjusting the ozone concentration, spray frequency and cold pressing parameters, the surface of the electrode 300 is treated with ozone, and the hydrophilicity is improved to a contact angle of <30°, which can effectively reduce stickiness and reduce the probability of sticking to the roller.

[0110] The parameters that need to be adjusted include, but are not limited to: ozone concentration of 0.5ppm-10ppm, spray frequency of 10Hz; cold pressing parameters: pressure of 60t-80t, speed of 20m / min-80m / min; particle size of anode active material of 50μm, and no obvious adhering particles on the surface of electrode 300 after cold pressing.

[0111] In an embodiment where the gas supply unit 21 is configured as a cryogenic gas pump and the nozzle 23 acts on the surface of the electrode 300, and the electrode 300 is an anode electrode 300, the cryogenic gas is transported to the nozzle 23 through the nozzle mounting plate 22. During the cold pressing process, the cryogenic gas is sprayed onto the surface of the electrode 300. The cryogenic gas impacts the surface of the electrode 300, reducing the surface temperature of the electrode 300 and reducing its tendency to adhere to the anode active material, which is silicon, graphite, or a composite material thereof.

[0112] In this process, the low-temperature gas acts on the surface of the electrode 300 through the nozzle 23, and the temperature, jet velocity and cold pressure parameters of the low-temperature gas are reasonably adjusted.

[0113] The parameters that need to be adjusted include, but are not limited to, the low-temperature gas temperature being -78.5℃ to -196℃, the jet flow rate being 10sccm-1000sccm, the cold pressing parameters being: pressure 60t-80t, speed 20m / min-80m / min, and the particle size of the anode silicon-containing material being 50μm. After cold pressing, there are no obvious adhering particles on the surface of the first roller 11.

[0114] like Figure 1 As shown, this application provides an electrode assembly production equipment 200, including: the electrode cold pressing device 100 in the above embodiment.

[0115] According to the electrode assembly production equipment 200 of the present application embodiment, by using the above-mentioned electrode cold pressing device 100, the quality of the electrode 300 can be improved, thereby improving the quality of the electrode assembly.

[0116] Other configurations and operations of the electrode cold pressing apparatus 100 and the electrode assembly production equipment 200 according to the embodiments of this application are known to those skilled in the art and will not be described in detail here.

[0117] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0118] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. An electrode cold pressing device, characterized in that, include: A cold pressing roller group (10) has a first roller (11) and a second roller (12) arranged opposite to each other, the first roller (11) and the second roller (12) defining a roller pressing channel (13), and an electrode (300) is adapted to pass through the roller pressing channel (13) to compact the electrode (300). A spraying assembly (20) is disposed upstream of the cold press roller group (10) and is used to perform gas spraying treatment on the surface of the electrode (300) and / or the surface of the first roller (11) to reduce the stickiness of the surface of the first roller (11) and / or the surface of the electrode (300).

2. The electrode cold pressing device according to claim 1, characterized in that, The spraying assembly (20) includes: a gas supply unit (21), a nozzle mounting plate (22), and a nozzle (23). The nozzle mounting plate (22) has a gas receiving cavity. The gas supply unit (21) is connected to the gas receiving cavity. The nozzle (23) is connected to the gas receiving cavity. The nozzle (23) is opposite to the surface of the electrode (300) and / or the nozzle (23) is opposite to the surface of the first roller (11).

3. The electrode cold pressing device according to claim 2, characterized in that, The length of the nozzle mounting plate (22) is greater than or equal to the width of the electrode (300).

4. The electrode cold pressing device according to claim 2, characterized in that, There are multiple nozzles (23), and the nozzles (23) are spaced apart on the nozzle mounting plate (22) along the length direction of the nozzle mounting plate (22).

5. The electrode cold pressing device according to claim 4, characterized in that, Among the plurality of nozzles (23), the center distance between the nozzles (23) located at both ends of the length of the nozzle mounting plate (22) is 100mm-2000mm.

6. The electrode cold pressing device according to claim 4, characterized in that, The distance between adjacent nozzles (23) is 10mm-200mm.

7. The electrode cold pressing apparatus according to any one of claims 2-6, characterized in that, The gas supply unit (21) is configured as an ozone generator.

8. The electrode cold pressing apparatus according to any one of claims 2-6, characterized in that, The gas supply unit (21) is configured as a cryogenic gas pump, and the cryogenic gas is configured to be either nitrogen or carbon dioxide.

9. The electrode cold pressing apparatus according to any one of claims 2-6, characterized in that, The electrode cold pressing device further includes a surface treatment component (30), which is disposed on the periphery of the first roller (11). The surface treatment component (30) is located upstream of the spraying component (20) in the rotation direction of the first roller (11) and is used to perform surface treatment on the surface of the first roller (11) upstream of the spraying component (20).

10. The electrode cold pressing device according to claim 9, characterized in that, The surface treatment assembly (30) has a laser cleaning head for laser cleaning the surface of the first roller (11).

11. The electrode cold pressing apparatus according to claim 9, characterized in that, The surface treatment assembly (30) has a scraper for scraping the surface of the first roller (11).

12. An electrode assembly manufacturing apparatus, characterized in that, include: The electrode cold pressing apparatus according to any one of claims 1 to 11.

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