Dry-method electrode preparation equipment

Abstract

The utility model relates to the technical field of battery processing, in particular to dry-method electrode preparation equipment which comprises a stock bin, a conveying belt, a material pressing assembly, a film pressing assembly and a compounding assembly, and the stock bin is used for containing powder and provided with a discharging port; the conveying belt is used for conveying powder flowing out of the discharging opening; the material pressing assembly is arranged on the side, away from the ground, of the conveying belt, and powder on the conveying belt is extruded to form a material belt. The film pressing assembly is arranged at the tail end of the conveying belt, and the thickness of the material belt is gradually reduced by continuously extruding the material belt to form a material film; the compounding assembly is arranged on the downstream side of the film pressing assembly and used for compounding the material film to the surface of the foil. According to the dry-method electrode preparation equipment, the belt breakage rate of the material film before the material film and the foil are compounded can be reduced, and the continuity of pole piece production can be maintained.

Description

Technical Field

[0001] The present application relates to the field of battery processing technology, and in particular to dry electrode preparation equipment. Background Art

[0002] The new energy vehicle industry is currently experiencing rapid growth. Compared to gasoline vehicles, these vehicles offer advantages such as environmental friendliness and low charging costs. However, these advantages remain, including range anxiety, charging anxiety, and cost competition from homogeneous batteries. Improving battery energy density and rate capability has drawn the attention of researchers. Traditional wet-process electrode technology increases energy density by increasing membrane thickness, which can lead to problems such as electrode cracking. Dry-process electrode technology, on the other hand, can effectively increase the coating surface density, thereby increasing energy density.

[0003] At present, dry electrode plates are prepared by dry method. Since there is no or only a very small amount of solvent in the electrode material, the adhesion of the electrode material to the foil is poor. Conventionally, the electrode material needs to be pressed into a plate film first, and then the plate film and the foil are hot-pressed and composited. However, after the electrode material is formed into a film, it is easy to break the belt when it flows over the roller before being composited with the foil, resulting in poor production continuity and low product qualification rate. Utility Model Content

[0004] The present application provides a dry electrode preparation device to solve the problem in the prior art that after the electrode material is formed into a film, the strip is easily broken when it flows through a roller before being composited with a foil material.

[0005] The present application provides a dry electrode preparation device, comprising:

[0006] The silo is used to store powder and has a discharge port;

[0007] Conveyor belt, used to convey the powder flowing out of the discharge port;

[0008] The pressing component is arranged on the side of the conveyor belt away from the ground, and forms a material belt by squeezing the powder on the conveyor belt;

[0009] The film pressing assembly is installed at the tail end of the conveyor belt, and forms a film by continuously squeezing the material belt to gradually reduce its thickness;

[0010] The composite component is arranged at the downstream side of the film pressing component and is used to composite the material film onto the surface of the foil material.

[0011] In one possible design, the die-cast assembly includes:

[0012] a first film-forming roller and a second film-forming roller, wherein a roller gap between the first film-forming roller and the second film-forming roller is smaller than a thickness of the material strip, and the first film-forming roller and the second film-forming roller squeeze the material strip to form a film;

[0013] The thinning roller is arranged on the downstream side of the second film-forming roller. The roller gap between the thinning roller and the second film-forming roller is smaller than the thickness of the material film. The thinning roller and the second film-forming roller reduce the thickness of the material film to a preset thickness by squeezing the material film.

[0014] In a possible design, there are multiple thinning rollers, and along the conveying direction of the thinning rollers, the roller gap between two adjacent thinning rollers gradually decreases.

[0015] In a possible design, the rotation speed of the thinning roller gradually increases along the conveying direction of the thinning roller.

[0016] In one possible design, the press assembly includes:

[0017] The material leveling piece is set at the position of the conveyor belt corresponding to the discharge port, and is used to spread the powder material on the conveyor belt evenly;

[0018] The pressing roller is arranged on the downstream side of the material leveling member and is used to squeeze the powder on the conveyor belt.

[0019] In one possible design, the screed element includes:

[0020] The central axis is perpendicular to the conveying direction of the conveyor belt;

[0021] The fan blades are evenly arranged on the central axis.

[0022] In a possible design, the pressing assembly further includes a scraping roller, and a scraping groove is formed on the roller surface of the scraping roller.

[0023] In one possible design, the silo includes:

[0024] Feed box;

[0025] The crushing box is connected to the feed box, and a crushing shaft is provided in the crushing box, and crushing blades are installed on the crushing shaft;

[0026] The screening box is connected with the crushing box, and a screen is arranged in the screening box.

[0027] In a possible design, a distributor is provided in the silo; and / or a vibrator is provided on the side wall of the silo.

[0028] In one possible design, the composite component includes:

[0029] Unwinding roller, used for unwinding the foil;

[0030] The first composite roller and the second composite roller are used to squeeze the film and the foil so that the film adheres to the surface of the foil to form an electrode.

[0031] The winding roller is used to wind up the pole piece.

[0032] The beneficial effects of this application are as follows:

[0033] The dry electrode preparation equipment of the present application is provided with a pressing assembly on the side of the conveyor belt away from the ground. The pressing assembly squeezes the powder on the conveyor belt to form a material belt on the conveyor belt first, and then the film pressing assembly continuously squeezes the material belt to gradually reduce the thickness of the material belt to form a material film. Finally, the material film that meets the thickness requirement is transported to the composite assembly and compounded to the surface of the foil. Therefore, in the process of the material film being transported to the composite assembly by the film pressing assembly, the thickness of the material film is gradually reduced. The thicker material film is beneficial to prevent the material film from breaking during the transportation process. At the same time, it can also meet the thickness of the material film transported to the composite assembly to meet the product requirements, thereby reducing the breakage rate of the material film before compounding with the foil, which is beneficial to maintaining the continuity of electrode production and improving the product qualification rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0035] Figure 1 A schematic diagram of the structure of a dry electrode preparation device provided in an embodiment of the present application;

[0036] Figure 2 A radial cross-sectional view of a scraper roller of a dry electrode preparation device provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of the structure of a material distributor for a dry electrode preparation device provided in an embodiment of the present application;

[0038] Figure 4 This is a schematic structural diagram of the material leveling component of the dry electrode preparation equipment provided in an embodiment of the present application.

[0039] Reference numerals:

[0040] 100, silo; 110, feed box; 120, crushing box; 121, crushing shaft; 122, crushing blade; 130, screening box; 131, screen; 140, distributor; 150, vibrator;

[0041] 200, conveyor belt;

[0042] 300, material pressing assembly; 310, material leveling member; 311, central axis; 312, fan blade; 320, scraper roller; 321, scraper groove; 330, pressure roller;

[0043] 400, film pressing assembly; 410, first film forming roller; 420, second film forming roller; 430, thinning roller;

[0044] 500, composite assembly; 510, unwinding roller; 520, first composite roller; 530, second composite roller; 540, winding roller. DETAILED DESCRIPTION

[0045] The following will clearly and completely describe the technical solutions of this application in conjunction with the embodiments. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] The following combination Figures 1-4 , describing the dry electrode preparation equipment provided in the embodiments of the present application.

[0047] Reference Figure 1 As shown, the dry electrode preparation equipment provided by the embodiment of the present application includes a silo 100, a conveyor belt 200, a pressing assembly 300, a film pressing assembly 400 and a composite assembly 500. The silo 100 is used to place powder and has a discharge port; the conveyor belt 200 is used to convey the powder flowing out of the discharge port; the pressing assembly 300 is arranged on the side of the conveyor belt 200 away from the ground, and forms a material belt by squeezing the powder on the conveyor belt 200; the film pressing assembly 400 is arranged at the tail end of the conveyor belt 200, and forms a material film by continuously squeezing the material belt so that the thickness of the material belt is gradually reduced; the composite assembly 500 is arranged on the downstream side of the film pressing assembly 400, and is used to composite the material film to the surface of the foil. Specifically, the pressing assembly 300, the film pressing assembly 400 and the composite assembly 500 can be a pressure plate that moves along a straight line or a roller that rotates around its own axis. In this way, the powder enters the conveyor belt 200 from the discharge port of the silo 100. Under the extrusion of the pressing component 300, the powder on the conveyor belt 200 is first pressed into a material belt, and the material belt is transported backward with the conveyor belt 200. Then, under the extrusion of the film pressing component 400, the material belt gradually reduces its thickness to form a material film. Finally, the material film with the required thickness is transported to the compounding component 500 and compounded to the surface of the foil.

[0048] By utilizing the technical solution in the above embodiment, the film pressing component 400 gradually reduces the thickness of the material strip by squeezing the material strip to form a material film with a thickness that meets the requirements, which is then compounded to the surface of the foil. In this way, in the process of the material film being transported to the composite component 500 by the film pressing component 400, the thicker material film is beneficial to preventing the material film from breaking during the transportation process. At the same time, as it is continuously transported backward, the material film is gradually pressed thinner, thereby meeting the thickness of the material film transported to the composite component 500 to meet the product requirements, thereby reducing the breakage rate of the material film before being compounded with the foil, which is beneficial to maintaining the continuity of electrode production.

[0049] Reference Figure 1 As shown, in some embodiments of the present application, the film pressing assembly 400 includes a first film forming roller 410, a second film forming roller 420 and a thinning roller 430, wherein the first film forming roller 410 is parallel to the second film forming roller 420, and the roller gap between the first film forming roller 410 and the second film forming roller 420 is smaller than the thickness of the material strip, and the material strip passes through the roller gap between the first film forming roller 410 and the second film forming roller 420, and the first film forming roller 410 and the second film forming roller 420 are rotated around their own axes. The thinning roller 430 and the second film-forming roller 420 rotate around their own axes to squeeze the material film so that the material film is reduced to a preset thickness. Among them, the diameter of the thinning roller 430 is 100-600mm, and the roller speed is 1m-100m / min; in this way, the material film extending from the roller gap between the first film forming roller 410 and the second film forming roller 420 can be directly wrapped around the second film forming roller 420 and enter between the second film forming roller 420 and the thinning roller 430 as the second film forming roller 420 rotates, thereby avoiding the material film from being suspended between the second film forming roller 420 and the thinning roller 430, which is beneficial to reducing the tension of the material film and preventing breakage.

[0050] In some embodiments, there are multiple thinning rollers 430, and the gap between two adjacent thinning rollers 430 gradually decreases along the conveying direction of the thinning rollers 430. By gradually reducing the gap between the thinning rollers 430, the thickness of the material film passing through the gap is gradually reduced, which is less likely to cause the film to break than thinning in one go. By providing multiple thinning rollers 430, the material film can be wound around the surface of the thinning rollers 430 as much as possible. When the thinning rollers 430 rotate, the material film adheres to the surface of the thinning rollers 430 and is transported backward as the thinning rollers 430 rotate. This can minimize the length of the material film suspended in the air, thereby reducing the tension of the material film during conveyance, which is conducive to preventing the material film from breaking.

[0051] Reference Figure 1 As shown, in some embodiments of the present application, the rotation speed of the thinning roller 430 gradually increases along the conveying direction of the thinning roller 430. By gradually increasing the rotation speed of the thinning roller 430, while squeezing the material film in the thickness direction, it can assist the thinning roller 430 in stretching the material film in the length direction. In addition, since the roller gap between two adjacent thinning rollers 430 gradually decreases along the conveying direction of the thinning roller 430, that is, the thickness of the material film decreases and the length increases, the speed of the rearward conveyance of the material film can be gradually accelerated by gradually increasing the rotation speed of the thinning roller 430, thereby minimizing the length of the material film suspended in the air and ensuring that the material film is wrapped around the surface of the thinning roller 430 as much as possible, which helps to reduce the tension of the material film during the conveying process and prevent the material film from breaking.

[0052] Reference Figure 1 、 Figure 4 As shown, in some embodiments provided in the present application, the pressing assembly 300 includes a material leveling member 310 and a pressure roller 330. The material leveling member 310 is arranged at a position corresponding to the discharge port of the conveyor belt 200 to evenly spread the powder on the conveyor belt 200; the pressure roller 330 is arranged on the downstream side of the material leveling member 310 to squeeze the powder on the conveyor belt 200.

[0053] In some specific embodiments, the number of material leveling members 310 may be one or more, each including a central shaft 311 and blades 312. The central shaft 311 is perpendicular to the conveying direction of the conveyor belt 200, and the blades 312 are evenly arranged on the central shaft 311. Specifically, the central shaft 311 is mounted on a frame and rotated by a motor. The blades 312 are evenly arranged on the sidewalls of the central shaft 311 along the axis of the central shaft 311. The blades 312 rotate around the central shaft 311 as the central shaft 311 rotates, thereby facilitating the even spreading of the powder on the conveyor belt 200. In some specific embodiments, the pressure rollers 330 are steel rods, and the number of pressure rollers 330 may be one or more. The spacing between the pressure rollers 330 and the conveyor belt 200 gradually decreases along the conveying direction of the conveyor belt 200, so that the powder on the conveyor belt 200 is sequentially squeezed by the pressure rollers 330 to form a material belt.

[0054] Reference Figure 2 As shown, in some embodiments provided in the present application, the pressing assembly 300 further includes a scraping roller 320, and a scraping groove 321 is provided on the roller surface of the scraping roller 320. Specifically, the scraping groove 321 is evenly provided on the surface of the scraping roller 320, and the scraping groove 321 extends along the axial direction of the scraping roller 320. The scraping groove 321 provided on the surface of the scraping roller 320 can, on the one hand, prevent the scraping roller 320 and the powder from slipping, and on the other hand, the scraping groove 321 can bring up the powder at a higher position when the scraping roller 320 rotates, which is conducive to keeping the powder evenly laid on the conveyor belt 200.

[0055] Reference Figure 1 As shown, in some embodiments provided in the present application, the silo 100 includes a feed box 110, a crushing box 120 and a screening box 130. The crushing box 120 is connected to the feed box 110. A crushing shaft 121 is provided in the crushing box 120, and a crushing blade 122 is installed on the crushing shaft 121; the screening box 130 is connected to the crushing box 120, and a screen 131 is provided in the screening box 130. The crushing shaft 121 is driven by the motor to rotate at a speed of 11-24 rpm / min, and the crushing blades 122 rotate with the crushing shaft 121. Since the powder particles will agglomerate, the crushing blades 122 rotating with the crushing shaft 121 slowly stir and crush the agglomerated powder particles at a speed of 1-24 rpm / min, and finally achieve uniform powder particle size. The crushed powder falls by gravity into the screening box 130 equipped with an 80-250 mesh screen 131. The screen 131 vibrates the powder in orbit under the drive of the vibration motor, screens out powder with uneven particle size, and discharges it to the outside. The uneven powder is recovered and processed, and the uniform powder enters the conveyor belt 200 under the action of gravity.

[0056] Reference Figure 1 、 Figure 3 As shown, in some embodiments provided in the present application, a distributor 140 is provided in the silo 100. Specifically, the distributor 140 is provided between the feed box 110 and the crushing box 120. The distributor 140 is a gear disk. The gear disk rotates at a speed of 1-100 rpm / min under the drive of the motor. The powder in the feed box 110 enters the distributor 140. The equidistant gears on the gear disk bring the input powder into the crushing box 120 in a uniform and quantitative manner. The number of teeth on the equidistant gears is 17-50, and the groove depth is 5-20 mm. One rotation of the gear disk is just the single delivery amount of the powder. In this way, by providing the distributor 140, the uniformity of the powder delivery can be improved. In some embodiments, the side wall of the silo 100 is provided with a vibrator 150. Specifically, the vibrator 150 is provided on the inner wall of the feed box 110. Under the vibration of the vibrator 150, the powder will fall into the distributor 140 in an orderly manner.

[0057] Reference Figure 1As shown, in some embodiments provided in the present application, the composite assembly 500 includes a unwinding roller 510, a first composite roller 520, a second composite roller 530 and a winding roller 540, the unwinding roller 510 is used to unwind the foil; the first composite roller 520 and the second composite roller 530 are parallel to each other, wherein the diameters of the first composite roller 520 and the second composite roller 530 are 400-800 mm, respectively, and the roller speeds are 1 m-100 m / min; the material film and the foil pass through the roller gap between the first composite roller 520 and the second composite roller 530, respectively, and the first composite roller 520 and the second composite roller 530 extrude the material film and the foil so that the material film adheres to the surface of the foil to form an electrode; the winding roller 540 is used to wind the electrode.

[0058] The workflow of the dry electrode preparation equipment of this application is as follows:

[0059] The mixer mixes the active material, conductive agent and binder according to certain process conditions to form powder. The powder is put into the feed box 110. Under the action of the vibrator 150, the powder falls to the distributor 140 in an orderly manner. The powder is brought into the crushing box 120 by the distributor 140. The crushing blades 122 slowly stir and crush the powder particles. The powder with uniform particles falls into the screening box 130. The screen 131 screens out the powder with uneven particle size and discharges it to the outside. The uniform powder passes through the screen 131 and falls onto the conveyor belt 200, and moves with the conveyor belt 200 to the material leveling member 310, where the powder contacts the fan blades 312 of the material leveling member 310 and is evenly spread under the action of the fan blades 312. The evenly spread powder continues to move with the conveyor belt 200 to the scraper roller 320, and when the scraper groove 321 rotates with the scraper roller 320, it can bring up the powder at a higher position, further making the powder evenly spread on the conveyor belt 200; Then, the powder moves to the position of the pressure roller 330 on the conveyor belt 200, and the pressure roller 330 flattens the powder to form a material belt; under the transmission of the conveyor belt 200, the material belt enters between the first film-forming roller 410 and the second film-forming roller 420, and with the set temperature and pressure, the binder in the powder is activated to form a three-dimensional network structure to bond the active substance and the conductive agent together to form a continuous material film. The initially formed material film is attached to the second film-forming roller 420 and continues to be transferred to each thinning roller 430 in turn. The thickness of the material film gradually decreases during the transfer process; at the same time, the foil of the unwinding roller 510 enters between the first composite roller 520 and the second composite roller 530. The initially formed thick film is transferred and thinned several times, and finally, it is single-sidedly bonded with the foil between the first composite roller 520 and the second composite roller 530 to form a 50-300um electrode, and is wound on the winding shaft; the film forming and electrode composite process on the other side of the foil are the same as the above steps.

[0060] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and 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 orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0061] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0062] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0063] In this application, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0064] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A dry electrode preparation device, characterized in that: include: The silo is used to store powder and has a discharge port; A conveyor belt, used for conveying the powder flowing out of the discharge port; A material pressing assembly is provided on a side of the conveyor belt away from the ground, and is configured to press the powder material on the conveyor belt to form a material belt; a film pressing assembly, arranged at the tail end of the conveyor belt, for forming a material film by continuously pressing the material belt to gradually reduce the thickness of the material belt; The composite component is arranged at the downstream side of the film pressing component and is used for composite the material film to the surface of the foil material.

2. The dry electrode preparation equipment according to claim 1, characterized in that: The film pressing assembly comprises: a first film-forming roller and a second film-forming roller, wherein a roller gap between the first film-forming roller and the second film-forming roller is smaller than a thickness of the material strip, and the first film-forming roller and the second film-forming roller squeeze the material strip to form a material film; The thinning roller is arranged on the downstream side of the second film-forming roller. The roller gap between the thinning roller and the second film-forming roller is smaller than the thickness of the material film. The thinning roller and the second film-forming roller reduce the thickness of the material film to a preset thickness by squeezing the material film.

3. The dry electrode preparation equipment according to claim 2, characterized in that: There are multiple thinning rollers, and along the conveying direction of the thinning rollers, the roller gap between two adjacent thinning rollers gradually decreases.

4. The dry electrode preparation equipment according to claim 3, characterized in that: Along the conveying direction of the thinning roller, the rotation speed of the thinning roller gradually increases.

5. The dry electrode preparation equipment according to any one of claims 1 to 4, characterized in that: The pressing component comprises: a material leveling member, provided at a position of the conveyor belt corresponding to the discharge port, for evenly spreading the powder on the conveyor belt; A pressing roller is provided on the downstream side of the material leveling member and is used for squeezing the powder on the conveyor belt.

6. The dry electrode preparation equipment according to claim 5, characterized in that: The material leveling member comprises: A central axis, perpendicular to the conveying direction of the conveyor belt; The fan blades are evenly arranged on the central axis.

7. The dry electrode preparation equipment according to claim 5, characterized in that: The pressing assembly further comprises a scraping roller, and a scraping groove is provided on the roller surface of the scraping roller.

8. The dry electrode preparation equipment according to any one of claims 1 to 4, characterized in that: The silo comprises: Feed box; A crushing box is connected to the feed box, wherein a crushing shaft is provided in the crushing box, and a crushing blade is installed on the crushing shaft; The screening box is connected to the crushing box, and a screen is provided in the screening box.

9. The dry electrode preparation device according to any one of claims 1 to 4, characterized in that: A distributor is provided in the silo; and / or a vibrator is provided on the side wall of the silo.

10. The dry electrode preparation equipment according to any one of claims 1 to 4, characterized in that: The composite assembly comprises: an unwinding roller, used for unwinding the foil; a first composite roller and a second composite roller, wherein the first composite roller and the second composite roller squeeze the material film and the foil material so that the material film adheres to the surface of the foil material to form an electrode piece; The winding roller is used to wind up the pole piece.

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