Dry-method electrode continuous preparation system

Abstract

The utility model relates to a dry method electrode continuous preparation system which comprises at least one feeding device, the output end of each feeding device is connected with the feeding end of a pre-pressing roller set, the discharging end of each pre-pressing roller set is connected with the feeding end of a calendering device, and the discharging end of each calendering device is connected with the feeding end of a re-pressing device. The automatic gluing machine further comprises a first unwinding device, the discharging end of the first unwinding device is connected with the feeding end of the re-pressing device, a gluing device is arranged at the discharging end of the first unwinding device, and the discharging end of the re-pressing device is connected with a first winding device. By arranging the calendering device and the compounding device, the preparation of the electrode pole piece can be realized based on a dry process, the energy consumption is low, the production cost is low, the environment-friendly requirement is met, the production efficiency is high, and the product quality is high.

Description

Technical Field

[0001] The utility model relates to the technical field of dry electrode preparation, in particular to a dry electrode continuous preparation system. Background Art

[0002] Lithium-ion batteries have become an ideal energy carrier with broad application prospects due to their advantages such as small size, high energy density and long cycle life.

[0003] In the prior art, electrodes are mainly prepared by wet process, which is to evenly apply solution or slurry on the surface of substrate, and then form electrode plates after drying and curing. The preparation system based on wet process needs to consume a lot of thermal energy to achieve production, which has high energy consumption and high production cost. At the same time, the solvent used in the preparation process is highly volatile, which is not conducive to environmental protection. Utility Model Content

[0004] In view of the shortcomings of the above-mentioned existing production technologies, the applicant provides a dry electrode continuous preparation system, which is energy-saving and environmentally friendly, can reduce energy consumption in lithium battery production, enhance product stability, and improve lithium battery performance.

[0005] The technical solution adopted by the utility model is as follows:

[0006] A dry electrode continuous preparation system, comprising at least one feeding device, wherein the output end of a single feeding device is connected to the feed end of a pre-pressing roller group, the discharge end of the pre-pressing roller group is connected to the feed end of a calendering device, and the discharge end of the calendering device is connected to the feed end of a re-pressing device;

[0007] It also includes a first unwinding device, wherein the discharge end of the first unwinding device is connected to the feed end of the re-pressing device, a gluing device is arranged at the discharge end of the first unwinding device, and the discharge end of the re-pressing device is connected to the first winding device;

[0008] The material fed by the feeding device is rolled by the pre-pressing roller group and the calendering device in sequence to form a membrane sheet;

[0009] The first unwinding device unwinds the substrate, and the glue coating device coats the adhesive on the substrate;

[0010] The re-pressing device presses the substrate coated with adhesive and the diaphragm to form a pole piece, and the pole piece is rolled up by the first rolling device.

[0011] As a further improvement of the above technical solution:

[0012] The calendering device adopts a heat-pressing roller group arranged in an array with intervals, and a cooling roller group is connected to the discharge end of the heat-pressing roller group.

[0013] The calendering device adopts a continuous rolling roller group.

[0014] The calendering device is equipped with a roller device for supporting and conveying the film, the roller device includes a film unwinding roller, the film unwinding roller is connected to the film winding roller through the film, and a plurality of roller groups are arranged between the film unwinding roller and the film winding roller, and the roller group supports the film.

[0015] The re-pressing device comprises a plurality of re-pressing roller groups which are arranged in an interval manner.

[0016] A second winding device and a second unwinding device are sequentially arranged between the calendering device and the re-pressing device.

[0017] A trimming device is arranged between the calendering device and the second winding device.

[0018] At least one set of tensioning rollers is arranged between the calendering device and the re-pressing device, and between the first unwinding device and the re-pressing device.

[0019] A deviation correcting device is arranged between the re-pressing device and the first winding device.

[0020] The feeding end of the feeding device is connected to the discharging end of the pre-processing unit, and the pre-processing unit is used to pre-process the powder for preparing the membrane;

[0021] The pre-treatment unit includes a jet mill, and the jet mill fiberizes the adhesive component in the material.

[0022] The beneficial effects of the utility model are as follows:

[0023] The utility model has a compact and reasonable structure and is easy to operate. By arranging a calendering device and a compounding device, the electrode pole piece can be prepared based on a dry process. It has low energy consumption, low production cost, meets environmental protection requirements, has high production efficiency and high product quality.

[0024] The utility model also has the following advantages:

[0025] (1) The feeding device in the utility model adopts a twin-screw kneading machine, which can stably force the feeding amount and ensure the consistency of the density and thickness of the membrane, thereby improving the quality of the electrode.

[0026] (2) The utility model provides a calendering device to increase the compaction density, prevent the solid components in the membrane from falling off, improve the quality of the membrane, and enhance its stability.

[0027] (3) The calendering device of the utility model adopts a hot pressing roller group, which can improve the strength, toughness and film forming stability of the membrane.

[0028] (4) The utility model provides a roller device to support the diaphragm, thereby preventing the diaphragm from breaking, ensuring the tensile strength of the diaphragm, and improving the continuity and stability of the production process.

[0029] (5) The re-pressing device in the present invention arranges multiple groups of re-pressing rollers to perform multiple roll pressing on the electrode sheet, thereby improving the bonding strength between the substrate and the diaphragm and ensuring product quality.

[0030] (6) In the present invention, by providing a second winding device and a second unwinding device, the requirements of the dry electrode continuous preparation system on the production site can be reduced and the flexibility of use can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of the utility model.

[0032] Figure 2 It is a structural schematic diagram of an embodiment of a calendering device in the utility model.

[0033] Figure 3 It is a structural schematic diagram of another embodiment of the calendering device in the utility model.

[0034] Figure 4 It is a structural schematic diagram of another embodiment of the pre-pressing roller group in the utility model.

[0035] Figure 5 It is a structural schematic diagram of the pre-processing unit in the utility model.

[0036] Among them: 1. Feeding device; 2. Pre-pressing roller group; 3. Calendering device; 4. Edge trimming device; 5. Tensioning roller group; 6. First winding device; 7. First unwinding device; 8. Second winding device; 9. Second unwinding device; 10. Re-pressing device; 11. Curing device; 12. Pre-slitting device; 13. Detection device; 14. Gluing device; 15. Roller; 16. Support roller device; 17. Correction device; 18. Air flow mill; 19. Bag opener; 20. Buffer tank; 21. Measuring tank; 22. Mixer;

[0037] 301, hot pressing roller group; 302, cooling roller group; 303, continuous rolling roller group;

[0038] 1001, re-pressing roller group;

[0039] 1601, roller group; 1602, film; 1603, film unwinding roller; 1604, film winding roller. DETAILED DESCRIPTION

[0040] The specific implementation of the present utility model is described below in conjunction with the accompanying drawings.

[0041] The structure and functions of the utility model are as follows:

[0042] like Figure 1-Figure 4 As shown, a dry electrode continuous preparation system includes at least one feeding device 1, the output end of a single feeding device 1 is connected to the feed end of a pre-pressing roller group 2, the discharge end of the pre-pressing roller group 2 is connected to the feed end of a calendering device 3, and the discharge end of the calendering device 3 is connected to the feed end of a re-pressing device 10; it also includes a first unwinding device 7, the discharge end of the first unwinding device 7 is connected to the feed end of the re-pressing device 10, a glue coating device 14 is arranged at the discharge end of the first unwinding device 7, and the discharge end of the re-pressing device 10 is connected to a first winding device 6; the material fed by the feeding device 1 is rolled through the pre-pressing roller group 2 and the calendering device 3 in turn to form a membrane; the first unwinding device 7 unwinds the substrate, and the glue coating device 14 applies adhesive glue on the substrate; the re-pressing device 10 presses the substrate coated with adhesive glue with the membrane to form an electrode sheet, and the electrode sheet is wound up by the first winding device 6. The dry electrode continuous preparation system of the utility model comprises a feeding device 1, a pre-pressing roller group 2, a calendering device 3, a first winding device 6, a first unwinding device 7, a re-pressing device 10, and a glue coating device 14; wherein,

[0043] The feeding device 1 adopts a twin-screw kneader, which can feed materials with a solid content of more than 95% to the feeding end of the pre-pressing roller group 2;

[0044] like Figure 5 As shown, the feeding end of the feeding device 1 is connected with the discharging end of the pre-treatment unit, and the pre-treatment unit is used to pre-treat the powder for preparing the membrane;

[0045] The pre-treatment unit includes a jet mill 18, which fiberizes the adhesive component in the material.

[0046] The pre-treatment unit further includes a bag opener 19, a discharge end of the bag opener 19 is connected to a feed end of a metering tank 21, a discharge end of the metering tank 21 is connected to a feed end of a mixer 22, a discharge end of the mixer 22 is connected to a jet mill 18, and a discharge end of the jet mill 18 is connected to a feeding device 12;

[0047] The bag opener 19 opens the ton bag, and the powder in the ton bag is transported to the metering tank 21, which accurately discharges the powder and transports the powder to the mixer 22, which mixes the powder uniformly and transports it to the feeding device 12 through the airflow mill 18;

[0048] The other discharge end of the metering tank 21 is also connected to the buffer tank 20 , and the buffer tank 20 is used to buffer the powder in the metering tank 21 .

[0049] The pre-pressing roller group 2 calenders the material into a film, such as Figure 1-3As shown, in one embodiment of the present invention, the pre-pressing roller set 2 can be arranged in the horizontal direction, or, as shown in FIG. Figure 4 As shown, in another embodiment of the utility model, it can also be arranged in the vertical direction; when arranged in the vertical direction, the number of hot pressing roller groups 301 in the subsequent calendering device 3 can be reduced, and two groups of hot pressing roller groups 301 can be arranged in actual production.

[0050] In the utility model, the calendering device 3 thins and finish-rolls the membrane formed by calendering of the pre-pressing roller group 2, thereby forming a membrane that meets the production requirements;

[0051] like Figure 1-Figure 2 As shown, in one embodiment of the utility model, the calendering device 3 adopts a hot pressing roller group 301 arranged in an array and spaced apart, and the discharge end of the hot pressing roller group 301 is connected with a cooling roller group 302; when the pre-pressing roller group 2 is arranged in the horizontal direction, four hot pressing roller groups 301 are provided, and along the conveying direction of the film, the discharge end of the last hot pressing roller group 301 is connected with the cooling roller group 302, and the cooling roller group 302 can cool the film rolled by the hot pressing roller group 302;

[0052] Or, if Figure 3 As shown, in another embodiment of the present invention, the calendering device 3 adopts a continuous rolling roller group 303, and the continuous rolling roller group 303 includes a plurality of single rollers rotating at differential speeds, and the rotation directions of two adjacent single rollers are opposite.

[0053] In addition, if Figure 2 As shown, the calendering device 3 is equipped with a roller device 16 for supporting and conveying the film. The film 1602 and the roller group 1601 of the roller device 6 can support the film, prevent the film from cracking, avoid its breakage, and ensure the stability of the production process;

[0054] The roller device 16 includes a film unwinding roller 1603, which is connected to a film winding roller 1604 via a film 1602. An array of roller groups 1601 are arranged between the film unwinding roller 1603 and the film winding roller 1604. The roller group 1601 supports the film 1602. The film 1602 is made of plastic and is bonded to the film during the film conveying process, thereby preventing the film from breaking and improving the tensile strength of the film.

[0055] like Figure 1 As shown, the re-pressing device 10 includes a plurality of re-pressing roller groups 1001 arranged in an interval arrangement. The re-pressing device 10 is used to press the substrate and the diaphragm together to form an electrode sheet. By setting multiple groups of re-pressing roller groups 1001 and performing multiple rolling operations on the electrode sheet, the bonding strength between the substrate and the diaphragm can be improved to ensure product quality.

[0056] In addition, a second winding device 8 and a second unwinding device 9 are sequentially arranged between the calendering device 3 and the re-pressing device 10. The second winding device 8 is used for winding the film, and the second unwinding device 9 is used for unwinding the film; by providing the second winding device 8 and the second unwinding device 9, the requirements of the dry electrode continuous preparation system for the production site can be reduced. When the production site is insufficient, the calendering device 3 and the re-pressing device 10 can be arranged separately, and the second winding device 8 is connected to the discharge end of the calendering device 3, and the second unwinding device 9 is connected to the feed end of the re-pressing device 10. The second winding device 8 winds up the film at the discharge end of the calendering device 3. After winding, the rolled film is unwound by the second unwinding device 9, so that the re-pressing device 10 presses the rolled film onto the end surface of the substrate.

[0057] At least one set of tension rollers 5 is arranged between the calendering device 3 and the re-pressing device 10, and between the first unwinding device 7 and the re-pressing device 10. The tension rollers 5 are used to change the tension of the film and substrate during the conveying process, so as to improve the conveying stability of the system.

[0058] When the pre-pressing roller group 2 is arranged in the horizontal direction, the pre-pressing roller group 2 and the calendering device 3 are connected by a roller 15. In addition, the calendering device 3 and the re-pressing device 10 are also connected by a roller 15. The roller 15 can change the movement direction of the membrane. The number and position of the roller 15 are adjusted according to actual usage requirements.

[0059] A trimming device 4 is arranged between the calendering device 3 and the second winding device 8. The trimming device 4 is used to trim excess edges and corners of the film to make the film have a regular shape.

[0060] A deviation-correcting device 17 is arranged between the re-pressing device 10 and the first winding device 6 ; the deviation-correcting device 17 prevents the pole piece from deviating.

[0061] A detection device 13 is arranged between the re-pressing device 10 and the first winding device 6 , and the detection device 13 is used to detect the thickness of the pole piece.

[0062] In addition, a curing device 11 and a pre-slitting device 12 are arranged between the re-pressing device 10 and the first winding device 6. The curing device 11 cures the adhesive bonding the film and the substrate, thereby further improving the bonding performance between the film and the substrate; the pre-slitting device 12 cuts the electrode to make the electrode regular in shape, which is convenient for subsequent processing.

[0063] In addition, the dry electrode continuous preparation system of the utility model can be used to prepare a pole piece with a single-sided membrane cover, and can also be used to prepare a pole piece with a double-sided membrane cover;

[0064] When used to prepare a double-sided covered film electrode, such as Figure 1As shown, the dry electrode continuous preparation system of the utility model includes at least two feeding devices 1, at least two groups of pre-pressing roller groups 2, at least two calendering devices 3, and corresponding auxiliary devices; when used to prepare electrode sheets with single-sided covered membranes, the number of feeding devices 1, pre-pressing roller groups 2, and calendering devices 3 can be reduced to save production costs.

[0065] The following is the specific examples section.

[0066] like Figure 1 As shown, this embodiment is used to prepare a pole piece with a double-sided covered membrane, and its specific structure is as follows:

[0067] The dry electrode continuous preparation system of this embodiment includes two sets of feeding devices 1, two sets of pre-pressing roller groups 2, two calendering devices 3, a first winding device 6, a first unwinding device 7, a re-pressing device 10, and a glue coating device 14;

[0068] In this embodiment, the pre-pressing roller group 2 is arranged in the horizontal direction; the calendering device 3 adopts the form of a hot pressing roller group 301 and a cooling roller group 302, and four groups of hot pressing roller groups 301 and one group of cooling roller groups 302 are arranged. Along the film conveying direction, the feeding end of the first group of hot pressing roller groups 301 corresponds to the feeding end of the calendering device 3, and the discharging end of the cooling roller group 302 corresponds to the discharging end of the calendering device 3;

[0069] Specifically, the discharge ends of the two feeding devices 1 are connected to the feed ends of the two pre-pressing roller groups 2 respectively, the discharge ends of the two pre-pressing roller groups 2 are connected to the feed ends of the two calendering devices 3 respectively, and the discharge ends of the two calendering devices 3 are connected to the feed end of the re-pressing device 10 at the same time;

[0070] The discharging end of the first unwinding device 7 is connected to the feeding end of the re-pressing device 10 , and the discharging end of the re-pressing device 10 is connected to the first rewinding device 6 .

[0071] The working process of this embodiment is as follows:

[0072] The two feeding devices 1 feed materials to the feeding ends of the corresponding pre-pressing roller groups 2 respectively, and the two pre-pressing roller groups 2 pre-press the corresponding materials into films respectively, and the two rolls of film sheets are respectively finely rolled and thinned by the corresponding calendering devices 3;

[0073] At the same time, the first unwinding device 7 unwinds the substrate, and the glue coating device 14 applies adhesive glue on both end surfaces of the substrate;

[0074] The two calendering devices 3 simultaneously convey the two rolls of film sheets after fine rolling and thinning to the feeding end of the re-pressing device 10, and the first unwinding device 7 conveys the substrate coated with adhesive to the feeding end of the re-pressing device 10. The re-pressing device 10 presses the two rolls of film sheets onto the two end surfaces of the substrate to form a pole piece;

[0075] Finally, the pole piece is rolled up by the first rolling device 6 .

[0076] The above description is an explanation of the utility model, not a limitation of the utility model. The scope of the utility model is defined by the claims. Any form of modification can be made within the protection scope of the utility model.

Claims

1. A dry electrode continuous preparation system, characterized in that: It comprises at least one feeding device (1), the output end of the single feeding device (1) is connected to the feeding end of the pre-pressing roller group (2), the discharge end of the pre-pressing roller group (2) is connected to the feeding end of the calendering device (3), and the discharge end of the calendering device (3) is connected to the feeding end of the re-pressing device (10); It also includes a first unwinding device (7), the material discharge end of the first unwinding device (7) is connected to the material feed end of the re-pressing device (10), a glue coating device (14) is arranged at the material discharge end of the first unwinding device (7), and the material discharge end of the re-pressing device (10) is connected to the first winding device (6); The material fed by the feeding device (1) is rolled by the pre-pressing roller group (2) and the calendering device (3) in sequence, thereby forming a membrane sheet; The first unwinding device (7) unwinds the substrate, and the glue coating device (14) applies adhesive glue on the substrate; The re-pressing device (10) presses the substrate coated with adhesive and the diaphragm to form a pole piece, and the pole piece is rolled up by the first rolling device (6).

2. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: The calendering device (3) adopts a heat-pressing roller group (301) arranged in an array with intervals, and a cooling roller group (302) is arranged in connection with the discharge end of the heat-pressing roller group (301).

3. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: The calendering device (3) adopts a continuous rolling roller group (303).

4. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: The calendering device (3) is equipped with a roller device (16) for supporting and conveying the film, the roller device (16) includes a film unwinding roller (1603), the film unwinding roller (1603) is connected to the film winding roller (1604) through the film (1602), and an array of roller groups (1601) are arranged between the film unwinding roller (1603) and the film winding roller (1604), and the roller group (1601) supports the film (1602).

5. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: The re-pressing device (10) comprises a plurality of re-pressing roller groups (1001) arranged in an alternating pattern.

6. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: A second winding device (8) and a second unwinding device (9) are arranged in sequence between the calendering device (3) and the re-pressing device (10).

7. A dry electrode continuous preparation system as claimed in claim 6, characterized in that: A trimming device (4) is arranged between the calendering device (3) and the second winding device (8).

8. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: At least one set of tensioning rollers (5) is arranged between the calendering device (3) and the re-pressing device (10), and between the first unwinding device (7) and the re-pressing device (10).

9. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: A deviation correction device (17) is arranged between the re-pressing device (10) and the first winding device (6).

10. A dry electrode continuous preparation system as claimed in claim 1, characterized in that: The feeding end of the feeding device (1) is connected to the discharging end of the pre-treatment unit, and the pre-treatment unit is used to pre-treat the powder for preparing the membrane; The pre-treatment unit comprises a jet mill (18), and the jet mill (18) fiberizes the adhesive component in the material.

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