A battery coating system

Abstract

The present application is related to the technical field of battery manufacturing, and provides a coating system for a battery. The coating system includes: an oven, which is provided with a first drying area and a second drying area; a gravure coating unit, which is used to gravure coat the foil, and transport the foil after the gravure coating process to the first drying area of ​​the oven for a primary drying process; an extrusion coating unit, which is used to extrusion coat the foil after the drying process in the first drying area, and transport the foil after the extrusion coating process to the second drying area of ​​the oven for a secondary drying process. The present application integrates gravure coating and extrusion coating into one, so that the two share an oven, which can save a lot of floor space, thereby reducing workshop manufacturing costs and staffing, reducing equipment investment costs, and improving the production efficiency of the coating process.

Description

Technical Field

[0001] The utility model relates to the field related to battery manufacturing, in particular to a battery coating system. Background Art

[0002] In the related technology, lithium-ion batteries have been widely used in the fields of household energy storage and power energy storage due to their advantages such as high energy density, long life, high efficiency, safety and environmental protection. Coating is a very important process in the lithium battery manufacturing process. During the coating process, the bonding strength between aluminum foil and binder and active material is limited. During the cycle charge and discharge, the volume of the electrode changes continuously, resulting in loose bonding between particulate matter and easy powder loss, which causes the battery capacity and cycle life to decay rapidly. In order to improve this defect, the aluminum foil is usually carbonized on the surface. Carbon-coated aluminum foil is a material used for the positive electrode current collector of lithium-ion batteries after adding a carbon coating layer on the surface of the aluminum foil. The carbon materials in the coating mainly include carbon black, graphite flakes and graphene. After the carbon material powder is mixed into a slurry with a certain film-forming agent, solvent and binder, it is coated on the surface of the aluminum foil and forms a dense carbon coating layer after drying. Compared with blank aluminum foil, carbon-coated aluminum foil has the advantages of increasing battery energy density, inhibiting battery polarization, reducing battery internal resistance and increasing battery cycle life. The carbon-coated aluminum foil needs to be primed with a gravure coater first, and then transferred to the coater for positive electrode coating after the primer is dried.

[0003] In the prior art, two types of equipment, a gravure coater and an extrusion coater, need to be set up at the same time, and both types of equipment need to be separately equipped with a winding and unwinding unit, a coating unit, an oven unit, and a traction unit. However, this will have the following disadvantages: the equipment occupies a large area, and the workshop manufacturing and maintenance costs are high; the production process is long and the efficiency is low; two devices need to be purchased for production, and the equipment cost is high; the production requires circulation, the staffing cost is high, and the manufacturing time is long. Utility Model Content

[0004] In view of this, the purpose of the present application is to provide a battery coating system to solve the technical problems existing in the prior art that the coating system occupies a large area, has low production efficiency and high cost.

[0005] In order to achieve the above objectives, this application provides the following technical solutions:

[0006] The present application provides a battery coating system, the coating system comprising:

[0007] A drying oven, wherein a first drying area and a second drying area are provided;

[0008] A gravure coating unit, used for gravure coating the foil, and conveying the foil after gravure coating into the first drying area of ​​the oven for a primary drying treatment;

[0009] The extrusion coating unit is used to perform extrusion coating on the foil after the drying treatment in the first drying area, and transport the foil after the extrusion coating treatment into the second drying area of ​​the oven for secondary drying treatment.

[0010] According to some embodiments of the present application, the first drying area is located at the upper part of the oven, and the second drying area is located at the lower part of the oven;

[0011] The oven comprises:

[0012] A first drying and conveying assembly is disposed in the first drying area and is used to perform a drying process on the foil material after the gravure coating process;

[0013] The second drying and conveying assembly is arranged in the second drying area and is used for performing a secondary drying treatment on the foil after the extrusion coating treatment.

[0014] According to some embodiments of the present application, the first drying and conveying component includes:

[0015] A plurality of first negative pressure rollers are arranged in the first drying area along a preset direction and are used to convey the foil;

[0016] At least one first air nozzle is arranged above the plurality of first negative pressure rollers, and is used for drying the foil material after the gravure coating process in the first drying area.

[0017] According to some embodiments of the present application, the second drying and conveying component includes:

[0018] A plurality of second negative pressure rollers are arranged in the second drying area along a preset direction and are used to convey the foil;

[0019] At least one second air nozzle is arranged below the plurality of second negative pressure rollers, and is used for performing a secondary drying treatment on the foil after the extrusion coating treatment in the second drying area.

[0020] According to some embodiments of the present application, the coating system further includes:

[0021] an unwinding device, arranged upstream of the gravure coating unit, for unwinding the foil material to cooperate with the gravure coating unit for gravure coating;

[0022] The winding device is arranged downstream of the oven and is used for winding the foil material after the secondary drying treatment in the oven.

[0023] According to some embodiments of the present application, the coating system further includes:

[0024] A first transmission roller, disposed between the unwinding device and the gravure coating unit, for conveying the foil;

[0025] The second transmission roller is arranged between the oven and the extrusion coating unit, and is used for transmitting the foil material after a drying treatment in the oven to the extrusion coating unit.

[0026] According to some embodiments of the present application, the coating system further includes:

[0027] The third transmission roller is arranged between the oven and the winding device, and is used to convey the foil material after the secondary drying treatment in the oven to the winding device.

[0028] According to some embodiments of the present application, the coating system further includes:

[0029] The third negative pressure roller is arranged between the extrusion coating unit and the oven, and is used for rotating and transmitting the foil material after extrusion coating by the extrusion coating unit to the oven for secondary drying treatment.

[0030] According to some embodiments of the present application, the coating system further includes:

[0031] The fourth transmission roller is arranged between the third negative pressure roller and the oven, and is used to assist the third negative pressure roller to transfer the foil material after extrusion coating by the extrusion coating unit to the oven.

[0032] According to some embodiments of the present application, the coating system further includes:

[0033] The glue dispensing mechanism is arranged between the gravure coating unit and the oven, and is used for applying glue to the foil material after the gravure coating process.

[0034] In the above technical solution, a battery coating system is provided. By integrating gravure coating and extrusion coating into one, the two share an oven, which can save a lot of floor space, thereby reducing workshop manufacturing costs and staffing, reducing equipment investment costs, and improving the production efficiency of the coating process. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1is a schematic diagram of a battery coating system according to an exemplary embodiment.

[0037] In the figure: 1. unwinding device; 2. first transmission roller; 3. gravure coating unit; 4. oven; 411. first air nozzle; 412. first negative pressure roller; 421. second negative pressure roller; 422. second air nozzle; 5. second transmission roller; 6. extrusion coating unit; 7. third negative pressure roller; 8. third transmission roller; 9. winding device. DETAILED DESCRIPTION

[0038] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0039] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0040] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0041] In the related technology, in the process of coating carbon aluminum foil, a gravure coater is required to first perform gravure primer coating, and after the primer is dried, it is transferred to the coater for positive electrode coating. Since the traditional method requires the simultaneous installation of two types of equipment, a gravure coater and an extrusion coater, and both types of equipment require separate winding and unwinding units, coating units, oven units, and traction units, this will result in a large overall footprint of the coating equipment, high workshop manufacturing and maintenance costs; long production processes and low efficiency; the purchase of two devices for production, high equipment costs; production requires circulation, high staffing costs, and long manufacturing time.

[0042] The present application provides a battery coating system, which integrates gravure coating and extrusion coating by optimizing the corresponding structure in the coating system so that the two can share an oven, thereby saving a lot of floor space (the oven is the unit with the largest floor space in the coating machine equipment), thereby reducing workshop manufacturing costs and staffing, reducing equipment investment costs, and improving the production efficiency of the coating process.

[0043] The technical solution of this embodiment is described in detail below in conjunction with the accompanying drawings. The following embodiments and implementation methods can be combined with each other if there is no conflict.

[0044] In an exemplary embodiment of the present utility model, a battery coating system is provided, such as Figure 1 As shown, Figure 1is a schematic diagram of a battery coating system according to an exemplary embodiment. The coating system includes:

[0045] A drying oven 4, which has a first drying area and a second drying area;

[0046] The gravure coating unit 3 is used to gravure coat the foil and transport the foil after gravure coating to the first drying area of ​​the oven 4 for a primary drying treatment;

[0047] The extrusion coating unit 6 is used to perform extrusion coating on the foil after the drying treatment in the first drying area, and transport the foil after the extrusion coating treatment into the second drying area of ​​the oven 4 for secondary drying treatment.

[0048] In this exemplary embodiment, the structure of the oven 4 is improved, and a first drying area and a second drying area are divided inside the oven 4, which are used to dry the foils processed by the gravure coating unit 3 and the extrusion coating unit 6, respectively. Since the gravure coating unit 3 and the extrusion coating unit 6 share one oven 4, the coating system forms a complete and continuous production line, and when the foils processed by the corresponding process are transported, the number of conveying rollers can be appropriately reduced. The coating system is miniaturized as a whole, which not only reduces the equipment investment cost, but also improves the production efficiency of the coating process while reducing the workshop manufacturing cost and staffing.

[0049] In some exemplary embodiments, Figure 1 As shown, considering that the foil is generally laid flat and transported in a horizontal or approximately horizontal direction, in order to realize that the gravure coating unit 3 and the extrusion coating unit 6 share one oven 4, the oven 4 can be divided into an upper and lower area as a first drying area and a second drying area, respectively. Exemplarily, the first drying area is located at the upper part of the oven 4, and the second drying area is located at the lower part of the oven 4.

[0050] Correspondingly, the oven 4 includes: a first drying conveying assembly, arranged in the first drying area, for performing a primary drying treatment on the foil after the gravure coating treatment; a second drying conveying assembly, arranged in the second drying area, for performing a secondary drying treatment on the foil after the extrusion coating treatment.

[0051] It should be noted that, in this embodiment, the example of "the first drying area for the primary drying treatment is located at the upper part of the oven 4, and the second drying area for the secondary drying treatment is located at the lower part of the oven 4" is used for explanation. In some other methods, the two can also be interchanged.

[0052] In some exemplary embodiments, Figure 1As shown, the first drying and conveying component includes: a plurality of first negative pressure rollers 412, which are arranged in a preset direction in the first drying area and are used for adsorbing and conveying the foil; at least one first air nozzle 411, which is arranged above the plurality of first negative pressure rollers 412 and is used for performing a drying treatment on the foil after gravure coating in the first drying area.

[0053] In this embodiment, the number of the first negative pressure roller 412 and the first air nozzle 411 can be determined according to actual needs. In order to realize the horizontal transmission of the foil, a plurality of first negative pressure rollers 412 are arranged in sequence in the horizontal direction on the upper part of the oven 4, wherein the foil is transmitted above the plurality of first negative pressure rollers 412. Since the first air nozzle 411 is arranged above the first negative pressure roller 412, when a plurality of first air nozzles 411 are used, they can be arranged in sequence along the foil transmission direction. At this time, during the foil transmission process, hot air is blown toward the foil below through the plurality of first air nozzles 411 to perform a drying process.

[0054] In some exemplary embodiments, Figure 1 As shown, the second drying and conveying assembly includes: a plurality of second negative pressure rollers 421, which are arranged in a preset direction in the second drying area and are used for adsorbing and conveying the foil; at least one second air nozzle 422, which is arranged below the plurality of second negative pressure rollers 421 and is used for performing secondary drying treatment on the foil after extrusion coating treatment in the second drying area.

[0055] In this embodiment, the number of the second negative pressure roller 421 and the second air nozzle 422 can also be determined according to actual needs. In order to realize the horizontal transmission of the foil, a plurality of second negative pressure rollers 421 are arranged in sequence in the horizontal direction at the lower part of the oven 4, wherein the foil is transmitted below the plurality of second negative pressure rollers 421. Since the second air nozzle 422 is arranged below the second negative pressure roller 421, when a plurality of second air nozzles 422 are used, they can be arranged in sequence along the foil transmission direction. At this time, during the foil transmission process, hot air is blown toward the foil above through the plurality of second air nozzles 422 for secondary drying.

[0056] It should be noted that, in order to ensure the reliability of the adsorption of the foil by the second negative pressure roller 421, the foil can also be conveyed on the upper side of multiple second negative pressure rollers 421, that is, similar to the design method of the first drying and conveying component. At this time, the position of the second air nozzle 422 is adaptively adjusted, and the second air nozzle 422 is set above the second negative pressure roller 421 and blows hot air downward to perform a secondary drying treatment on the foil.

[0057] In some exemplary embodiments, Figure 1As shown, the coating system also includes: a reeling device 1, which is arranged upstream of the gravure coating unit 3 and is used to reel the foil material to cooperate with the gravure coating unit 3 for gravure coating; a reeling device 9, which is arranged downstream of the oven 4 and is used to reel the foil material after secondary drying treatment in the oven 4.

[0058] Considering that there is a certain distance between the unwinding device 1 and the gravure coating unit 3, and there is also a certain distance between the oven 4 and the extrusion coating unit 6, in order to ensure the efficiency and reliability of the foil conveying, a transmission roller can also be equipped for auxiliary conveying. Exemplarily, the coating system also includes: a first transmission roller 2, arranged between the unwinding device 1 and the gravure coating unit 3, for conveying the foil; and / or, a second transmission roller 5, arranged between the oven 4 and the extrusion coating unit 6, for conveying the foil after a drying treatment in the oven 4 to the extrusion coating unit 6.

[0059] In some exemplary embodiments, Figure 1 As shown, since the distance between the oven 4 and the winding device 9 is relatively large, similar to the above-mentioned method of adding the first transmission roller 2 and the second transmission roller 5, a certain number of third transmission rollers 8 can also be arranged between the two to assist in transmission. Exemplarily, the coating system also includes: a third transmission roller 8, which is arranged between the oven 4 and the winding device 9, and is used to transmit the foil material after the secondary drying treatment in the oven 4 to the winding device 9.

[0060] In some exemplary embodiments, Figure 1 As shown, considering that the foil is processed by the extrusion coating unit 6 and then rotated and transported, and to ensure that the foil does not slip during the return process, a negative pressure roller can be arranged between the extrusion coating unit 6 and the oven 4 to adjust the conveying path of the foil. Exemplarily, the coating system also includes: a third negative pressure roller 7, which is arranged between the extrusion coating unit 6 and the oven 4, and is used to rotate and transport the foil after extrusion coating by the extrusion coating unit 6 to the oven 4 for secondary drying treatment.

[0061] Since the foil conveyed out of the oven 4 forms a foil conveying section, the foil processed by the extrusion coating unit 6 is conveyed back to the oven 4 to form another foil conveying section. Based on the added third negative pressure roller 7, the rotation path between the two foil conveying sections can be greatly reduced, thereby reducing the overall floor space of the coating equipment.

[0062] The coating system in this embodiment is based on the integration of the gravure coating unit 3 and the extrusion coating unit 6, so that the two can share an oven 4, and then configure corresponding transmission rollers and negative pressure rollers for transmission and rotation of the transmission path, which greatly reduces the overall footprint of the equipment, relieves the pressure on the factory building, and can also reduce the cost of personnel allocation and equipment investment, making the flow between processes faster, reducing time costs, and improving production efficiency.

[0063] In some exemplary embodiments, Figure 1 As shown, considering that there is also a distance between the third negative pressure roller 7 and the oven 4, a fourth transmission roller may be provided to assist in conveying the foil. Exemplarily, the coating system in this embodiment further includes: a fourth transmission roller, provided between the third negative pressure roller 7 and the oven 4, for assisting the third negative pressure roller 7 to convey the foil after extrusion coating by the extrusion coating unit 6 to the oven 4.

[0064] In this embodiment, the foil (empty aluminum foil) is unwound by the unwinding device 1; the foil is conveyed through the first transmission roller 2, and is subjected to gravure coating treatment when conveyed to the gravure coating unit 3; after the gravure coating, the foil is added to the oven 4, and since the thickness of the slurry coated on the gravure is relatively thin and the fluidity is not large, this device can be used to absorb the foil for conveying, that is, the foil after the gravure coating treatment is heated and dried by the first air nozzle 411 on the oven 4, and the foil is conveyed above the inside of the oven 4 by the first negative pressure roller 412; then the foil is conveyed by the second transmission roller 5 (at this time, it has been processed into a primer electrode); and then the extrusion coating is used. The coating unit 6 extrude-coats the foil; the third negative pressure roller 7 assists the coated foil to be adsorbed and conveyed, at which time the conveying direction of the foil is adjusted to form a rotary conveying; the fourth transmission roller assists the third negative pressure roller 7 to convey the foil that has been extruded and coated by the extrusion coating unit 6 to the oven 4; the second negative pressure roller 421 in the oven 4 adsorbs the foil and conveys it in the oven 4, at which time the second air nozzle 422 at the bottom of the oven 4 is used to heat and dry the foil; the foil (coated electrode) is conveyed normally after secondary drying assisted by the third transmission roller 8; finally, the winding device 9 winds up the manufactured electrode.

[0065] In some exemplary embodiments, the coating system further includes: a glue dispensing mechanism (not shown in the figure), which is arranged between the gravure coating unit 3 and the oven 4 and is used to perform glue coating on the foil material processed by the gravure coating unit 3 .

[0066] In this embodiment, the ear glue is applied to the foil after being processed by the gravure coating unit 3 through the glue dispensing mechanism, and after drying, the lithium battery slurry is coated on the other side through the extrusion coating unit 6, which can avoid the problems of mutual dissolution and virtual edges between the ear glue and the material area during drying.

[0067] In the description of the present application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of the present application. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present application.

[0068] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0069] The present application has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, various replacements and improvements may be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A battery coating system, characterized in that: The coating system comprises: A drying oven, wherein a first drying area and a second drying area are provided; A gravure coating unit, used for gravure coating the foil, and conveying the foil after gravure coating into the first drying area of ​​the oven for a primary drying treatment; The extrusion coating unit is used to perform extrusion coating on the foil after the drying treatment in the first drying area, and transport the foil after the extrusion coating treatment into the second drying area of ​​the oven for secondary drying treatment.

2. The battery coating system according to claim 1, characterized in that: The first drying area is located at the upper part of the oven, and the second drying area is located at the lower part of the oven; The oven comprises: A first drying and conveying assembly is disposed in the first drying area and is used to perform a drying process on the foil material after the gravure coating process; The second drying and conveying assembly is arranged in the second drying area and is used for performing a secondary drying treatment on the foil after the extrusion coating treatment.

3. The battery coating system according to claim 2, characterized in that: The first drying and conveying component comprises: A plurality of first negative pressure rollers are arranged in the first drying area along a preset direction and are used to convey the foil; At least one first air nozzle is arranged above the plurality of first negative pressure rollers, and is used for drying the foil material after the gravure coating process in the first drying area.

4. The battery coating system according to claim 2, characterized in that: The second drying and conveying assembly comprises: A plurality of second negative pressure rollers are arranged in the second drying area along a preset direction and are used to convey the foil; At least one second air nozzle is arranged below the plurality of second negative pressure rollers, and is used for performing a secondary drying treatment on the foil after the extrusion coating treatment in the second drying area.

5. The battery coating system according to any one of claims 1 to 4, characterized in that: The coating system also includes: an unwinding device, arranged upstream of the gravure coating unit, for unwinding the foil material to cooperate with the gravure coating unit for gravure coating; The winding device is arranged downstream of the oven and is used for winding the foil material after the secondary drying treatment in the oven.

6. The battery coating system according to claim 5, characterized in that: The coating system also includes: A first transmission roller, disposed between the unwinding device and the gravure coating unit, for conveying the foil; The second transmission roller is arranged between the oven and the extrusion coating unit, and is used for transmitting the foil material after a drying treatment in the oven to the extrusion coating unit.

7. The battery coating system according to claim 5, characterized in that: The coating system also includes: The third transmission roller is arranged between the oven and the winding device, and is used to convey the foil material after the secondary drying treatment in the oven to the winding device.

8. The battery coating system according to claim 5, characterized in that: The coating system also includes: The third negative pressure roller is arranged between the extrusion coating unit and the oven, and is used for rotating and transmitting the foil material after extrusion coating by the extrusion coating unit to the oven for secondary drying treatment.

9. The battery coating system according to claim 8, characterized in that: The coating system also includes: The fourth transmission roller is arranged between the third negative pressure roller and the oven, and is used to assist the third negative pressure roller to transfer the foil material after extrusion coating by the extrusion coating unit to the oven.

10. The battery coating system according to claim 5, characterized in that: The coating system also includes: The glue dispensing mechanism is arranged between the gravure coating unit and the oven, and is used for applying glue to the foil material after the gravure coating process.

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