Dry-method pole piece continuous rolling system
Through the dry electrode sheet continuous rolling system, the feed roller group and continuous roll group with different rotation center heights are used to solve the problem of using organic solvents and drying when wet coating in lithium battery sheet production, and efficient and safe dry preparation is achieved, saving costs and improving preparation efficiency.
Patent Information
- Application Number
- CN202422039239.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2034-08-21
AI Technical Summary
In the production of existing lithium battery electrodes, the wet coating process uses a large amount of organic solvents, which harms the health of operators and requires a long oven to dry, increasing production costs and energy consumption.
The dry-method electrode sheet continuous rolling system is adopted, and the feed roller set and continuous roll group with different rotation center heights are set to efficiently prepare lithium battery electrode sheets in the dry process, avoiding the use of organic solvents and ovens.
There is no need to use organic solvents and ovens, which effectively saves production costs, improves production safety, and realizes the continuous thinning and overlaying functions of the diaphragm, improving preparation efficiency.
Smart Images
Figure CN223030180U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of calenders, in particular to a dry-type pole piece continuous rolling system. Background Art
[0002] At present, the production of pole pieces in the lithium battery industry still mainly uses wet coating, that is, the materials are first stirred into a slurry and then coated. However, a large amount of organic solvents are used in the wet coating process, which is harmful to the health of operators; at the same time, a sufficiently long oven needs to be arranged for drying, thus increasing the production cost and energy consumption. Summary of the Utility Model
[0003] The applicant of the present utility model aims at the above-mentioned disadvantages in the existing production technology, and provides a dry-type pole piece continuous rolling system. By setting a feeding roll group and a continuous rolling roll group with different rotational center heights, the lithium battery pole pieces can be efficiently prepared based on the dry process, so that a large amount of organic solvents do not need to be used, and an oven does not need to be set, effectively saving the production cost and improving the production safety.
[0004] The technical solution adopted by the present utility model is as follows:
[0005] A dry-type pole piece continuous rolling system includes at least one group of feeding roll groups. The discharging end of a single group of feeding roll groups is connected and arranged with a continuous rolling roll group. A single group of feeding roll groups roll and form a powder material into a film sheet, and the film sheet is discharged after being continuously rolled and thinned by the corresponding continuous rolling roll group;
[0006] A single group of feeding roll groups includes several calender rolls, and the rotational center heights of adjacent two calender rolls are different. A single group of continuous rolling roll groups includes several continuous rolling rolls, and the rotational center heights of adjacent two continuous rolling rolls are different, so that the running angle of the film sheet on each roll is less than 180°.
[0007] As a further improvement of the above technical solution:
[0008] The rotational center height of each calender roll in the feeding roll group is different from the rotational center height of each continuous rolling roll in the continuous rolling roll group.
[0009] A single group of feeding roll groups includes a first calender roll and a second calender roll arranged in sequence from the feeding to the discharging direction. A first roll gap is formed between the first calender roll and the second calender roll, and the rotational center of the second calender roll is higher than the rotational center of the first calender roll.
[0010] A first back roll is connected and arranged in front of the first calender roll, and the rotational center of the first back roll is lower than the rotational center of the first calender roll.
[0011] The single - group continuous rolling roll group includes a first continuous rolling roll unit and a second continuous rolling roll unit that cooperate with each other. The first continuous rolling roll unit includes several first continuous rolling rolls, and the second continuous rolling roll unit includes several second continuous rolling rolls;
[0012] A second continuous rolling roll is arranged between two adjacent first continuous rolling rolls, so that the first continuous rolling rolls and the second continuous rolling rolls are alternately distributed in sequence. A second roll gap is formed between a first continuous rolling roll and the adjacent second continuous rolling roll.
[0013] The rotational center heights of the first continuous rolling rolls in the first continuous rolling roll unit are equal, and the rotational center heights of the second continuous rolling rolls in the second continuous rolling roll unit are equal.
[0014] The rotational center of the first continuous rolling roll is lower than the rotational center of the second continuous rolling roll.
[0015] A second backing roll is arranged at the rear of the single - group continuous rolling roll group. The rotational center of the second backing roll is higher than the rotational center of the first continuous rolling roll in the first continuous rolling roll unit.
[0016] The roll diameters of the calendering rolls in the feeding roll group are smaller than the roll diameters of the continuous rolling rolls in the continuous rolling roll group.
[0017] A feeding device is installed at the feeding end of the single - group feeding roll group.
[0018] The beneficial effects of the present utility model are as follows:
[0019] The structure of the present utility model is compact and reasonable, and it is convenient to operate. By setting the feeding roll group and the continuous rolling roll group, the functions of continuous thinning and pole - piece lamination can be realized, so as to prepare diaphragm from powder materials. Without using a large amount of organic solvents and without setting an oven, the production cost can be effectively saved and the production safety can be improved; at the same time, the overall structure of the system is compact and the space utilization rate is high.
[0020] The present utility model also has the following advantages:
[0021] (1) In the present utility model, by reasonably arranging the rotational center heights of the rolls in the system, the running - belt angle of the diaphragm on each roll can be less than 180° when the diaphragm passes through the corresponding roll, so that the horizontal speed component of the diaphragm is the same as the total advancing direction X of the diaphragm from the feeding end to the discharging end, ensuring smooth running of the diaphragm, improving the surface compactness of the diaphragm, and preventing tearing damage to the diaphragm surface when the diaphragm separates from each roll in the system.
[0022] (2) In the present utility model, by setting the calendering rolls, the shearing force on the material can be increased, thus ensuring the uniformity and compaction density of the diaphragm; by setting the continuous rolling rolls, the diaphragm can be continuously thinned.
[0023] (3) In the present utility model, by providing the first back roll and the second back roll, the system rigidity can be improved, enabling the feeding roll group and the continuous rolling roll group to obtain stable rolling forces. In addition, the second back roll can also be used as a working roll, with a clever design and high flexibility in use.
[0024] (4) In the present utility model, by reasonably setting the widths of the respective roll gaps, continuous precision rolling and thinning of the diaphragm can be achieved. At the same time, the internal stress generated during multiple rolling processes of the diaphragm can be released, improving the film-making quality.
[0025] (5) In the present utility model, by reasonably setting the roll diameters of the respective rolls, the feeding roll group can obtain a greater shearing force, improving the uniformity during the diaphragm forming process, so as to obtain a more uniform diaphragm.
[0026] (6) In the present utility model, by reasonably setting the roll speeds of the respective rolls, the adhesion forces on both sides of the diaphragm in the system can be controlled, enabling smooth running of the web. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 is a schematic structural view of the first embodiment of the present utility model.
[0028] Figure 2 is a schematic view of the web running angle when the diaphragm passes through the corresponding rolls in the first embodiment.
[0029] Figure 3 is a schematic view of the comparison of the rotational center heights between the respective rolls in the first embodiment.
[0030] Figure 4 is a schematic structural view of the second embodiment of the present utility model.
[0031] Wherein: 1, feeding roll group; 2, continuous rolling roll group; 3, feeding device; 4, frame; 5, first back roll; 6, second back roll; 7, metal foil;
[0032] 101, first calender roll; 102, second calender roll;
[0033] 201, first continuous rolling roll; 202, second continuous rolling roll. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0034] The following will describe the specific embodiments of the present utility model with reference to the accompanying drawings.
[0035] The structure and functions of the present utility model are as follows:
[0036] As Figures 1 - 4As shown in the figure, a dry-type pole piece continuous rolling system includes at least one set of feeding roller groups 1. The discharging end of a single set of feeding roller groups 1 is connected and arranged with a continuous rolling roller group 2. A single set of feeding roller groups 1 calenders and forms a film sheet from the powder material. After the film sheet is continuously rolled and thinned by the corresponding continuous rolling roller group 2, it is discharged. A single set of feeding roller groups 1 includes several calendering rollers, and the rotational center heights of adjacent two calendering rollers are different. A single set of continuous rolling roller group 2 includes several continuous rolling rollers, and the rotational center heights of adjacent two continuous rolling rollers are different, so that the running belt angle of the film sheet on each roller is less than 180°. The dry-type pole piece continuous rolling system of the present utility model is based on a dry process for preparing lithium battery pole pieces. By setting the feeding roller groups 1, various powder materials can be directly calendered to form a film sheet. By setting the continuous rolling roller group 2, the formed film sheet is continuously rolled and thinned to meet the production requirements. Finally, the film sheet is attached to the surface of the metal foil 7, so that the preparation of the lithium battery pole piece can be completed.
[0037] A feeding device 3 is equipped at the feeding end of a single set of feeding roller groups 1. The feeding device 3 is used for feeding the powder material. Its discharging nozzle corresponds to the first roll gap. The feeding device 3 conveys the powder material into the first roll gap, so that the powder material is calendered and formed by the first calendering roller 101 and the second calendering roller 102.
[0038] A single set of feeding roller groups 1 includes a first calendering roller 101 and a second calendering roller 102 arranged in sequence along the feeding to discharging direction. A first roll gap is formed between the first calendering roller 101 and the second calendering roller 102. The rotational center of the second calendering roller 102 is higher than that of the first calendering roller 101. In the present utility model, the feeding roller group 1 includes two calendering rollers, namely the first calendering roller 101 and the second calendering roller 102. The first calendering roller 101 and the second calendering roller 102 are respectively driven by two independent motors, so as to independently control the speeds and torques of the two calendering rollers.
[0039] A first backing roller 5 is connected and arranged in front of the first calendering roller 101. The rotational center of the first backing roller 5 is lower than that of the first calendering roller 101. Along the feeding to discharging direction, the first backing roller 5 is arranged in front of the first calendering roller 101. There is no roll gap between the first backing roller 5 and the first calendering roller 101. When the system works, the first backing roller 5 rotates driven by the first calendering roller 101, and it is used to improve the working stability of the feeding roller group 1.
[0040] A single set of continuous rolling roller group 2 includes a first continuous rolling roller unit and a second continuous rolling roller unit that cooperate with each other. The first continuous rolling roller unit includes several first continuous rolling rollers 201, and the second continuous rolling roller unit includes several second continuous rolling rollers 202. A second continuous rolling roller 202 is arranged between adjacent two first continuous rolling rollers 201, so that the first continuous rolling rollers 201 and the second continuous rolling rollers 202 are alternately distributed in sequence. A second roll gap is formed between the first continuous rolling roller 201 and the adjacent second continuous rolling roller 202.
[0041] A third roll gap is formed between the second calender roll 102 and the corresponding tandem rolling roll group 2. Specifically, a third roll gap is formed between the second calender roll 102 and the first first tandem rolling roll 201 at the head of the first tandem rolling roll unit of the corresponding tandem rolling roll group 2. The diaphragm passes through the second roll gap and the third roll gap in sequence, so as to carry out finish rolling and thinning to improve the compactness of the diaphragm.
[0042] A second backup roll 6 is arranged at the rear of a single set of tandem rolling roll group 2, and the rotation center of the second backup roll 6 is higher than the rotation center of the first tandem rolling roll 201 in the first tandem rolling roll unit. Along the feeding to discharging direction, the second backup roll 6 is arranged at the rear of the tandem rolling roll group 2. Specifically, the second backup roll 6 is arranged in connection with the last first tandem rolling roll 201 in the first tandem rolling roll unit of the tandem rolling roll group 2; the second backup roll 6 can be used as an auxiliary roll or a working roll. When the second backup roll 6 is used as a working roll, a fourth roll gap is formed between the second backup roll 6 and the last first tandem rolling roll 201. The second backup roll 6 is driven by an independent motor and cooperates with the last first tandem rolling roll 201 to carry out calendering rolling treatment on the diaphragm; when the second backup roll 6 is used as an auxiliary roll, no roll gap is provided between the second backup roll 6 and the last first tandem rolling roll 201. During the working process of the system, the second backup roll 6 rotates with the last first tandem rolling roll 201, so as to improve the working stability of the tandem rolling roll group 2.
[0043] In addition, the roll diameter of the second backup roll 6 is larger than the roll diameter of the tandem rolling rolls in the tandem rolling roll group 2, so that when it is used as a working roll, the rolling force on the diaphragm can be increased, thereby improving the product quality.
[0044] As Figure 2 、 Figure 3 shown, Figure 2 the arrow in Figure 3 indicates the rotation direction of the first calender roll 101, and the arrow X indicates the total traveling direction of the diaphragm along the feeding to discharging direction. In
[0045] the rotation centers of each calender roll in the feeding roll group 1 are different from the rotation centers of each tandem rolling roll in the tandem rolling roll group 2;
[0046] the rotation centers of each first tandem rolling roll 201 in the first tandem rolling roll unit are equal, and the rotation centers of each second tandem rolling roll 202 in the second tandem rolling roll unit are equal;
[0047] the rotation center of the first tandem rolling roll 201 is lower than the rotation center of the second tandem rolling roll 202;
[0048] The rotation center of the first calender roll 101 is lower than that of the second calender roll 102, the rotation center of the first back roll 5 is lower than that of the first calender roll 101, and the rotation center of the second back roll 6 is higher than that of the first continuous rolling roll 201 in the first continuous rolling roll unit;
[0049] The rotation centers of the first back roll 5 and the second back roll 6 are at the same height;
[0050] By arranging the rotation centers of the calender rolls, continuous rolling rolls, and back rolls accordingly, it can be ensured that during the operation of the system, when the diaphragm passes through the corresponding rolls, the running angle of the diaphragm on each roll is less than 180°; that is, as Figure 2 shown, θ1 represents the running angle of the diaphragm on the second calender roll 102 during the process of powder feeding and calendering of the diaphragm by the feeding roll group 1, that is,
[0051] Taking the center of the second calender roll 102 as the origin, a straight line is connected to the center of the first calender roll 101 and a straight line is connected to the center of the first continuous rolling roll 201 at the head of the corresponding continuous rolling roll group 2, respectively, so as to form a corresponding running angle between the two straight lines. The radian corresponding to this running angle is the travel of the diaphragm on the first calender roll 101;
[0052] Figure 2 The calculation principles of the remaining running angles θ2, θ3, θ4, θ5, and θ6 are similar to that of θ1 and will not be elaborated here.
[0053] In the present utility model, each running angle is less than 180°, so that the travel of the diaphragm on the corresponding roll is less than half of the circumference of the roll, thereby ensuring that at the outlet of each roll gap, the horizontal velocity component of the diaphragm is the same as the total advancing direction X of the diaphragm from the inlet to the outlet ( Figure 2 the dashed triangle in represents the velocity vector triangle of the diaphragm at the third roll gap), thereby ensuring smooth running of the diaphragm, improving the surface density of the diaphragm, and preventing tearing damage to the surface of the diaphragm when the diaphragm separates from each roll in the system.
[0054] In addition, along the direction from the inlet to the outlet, the rotational speeds of the first calender roll 101, the second calender roll 102, and each continuous rolling roll in the continuous rolling roll group 2 gradually increase (the rotational speed increments of each subsequent roll compared to the previous roll can be the same or different), thereby enabling control of the adhesion force on both sides of the diaphragm in the system and ensuring smooth running of the diaphragm.
[0055] In the present utility model, there are a first roll gap formed between the first calender roll 101 and the second calender roll 102, a second roll gap formed between the first calender roll 101 and the adjacent second calender roll 102, a third roll gap between the second calender roll 102 and the first calender roll 101 at the head, and a fourth roll gap formed between the last first tandem roll 101 and the second backup roll 6 when the second backup roll 6 is used as a working roll;
[0056] The arrangement order of each roll gap is as follows: along the feeding to discharging direction, they are arranged in sequence as the first roll gap, the third roll gap, each second roll gap, and the fourth roll gap;
[0057] The widths of each roll gap generally show a gradually decreasing trend according to the arrangement order along the feeding to discharging direction. Moreover, except for the first roll gap (corresponding to the first roll gap) and the last roll gap (corresponding to the last second roll gap or the fourth roll gap), among the remaining roll gaps, there is at least one roll gap with a width greater than that of the previous roll gap, so as to release the internal stress generated during multiple rolling processes of the diaphragm and improve the film-making quality.
[0058] The roll diameters of the calender rolls in the feeding roll group 1 are smaller than those of the tandem rolls in the tandem roll group 2, and moreover, the roll diameters of the calender rolls in the feeding roll group 1 are smaller than the roll diameter of the first backup roll 5. The smaller roll diameters can bring greater shear force to the feeding roll group 1 and improve the uniformity during the diaphragm forming process, so as to obtain a more uniform diaphragm.
[0059] In addition, by selecting the first backup roll 5 and the second backup roll 6 with larger roll diameters, the calender rolls and tandem rolls in the system can obtain stable rolling force and higher rigidity, thereby improving the working stability of the system.
[0060] In the present utility model, a group of feeding roll group 1 and a group of tandem roll group 2 can be arranged to prepare the powder material into a diaphragm; two groups of feeding roll group 1 and two groups of tandem roll group 2 can also be arranged to prepare the powder material into a diaphragm and laminate it on a metal foil. Specific arrangements can be made according to actual production requirements.
[0061] The feeding to discharging direction referred to in the present utility model is Figure 2 the total advancing direction X of the diaphragm along the feeding to discharging direction in
[0062] In addition, in the present utility model, the feeding roll group 1, the tandem roll group 2, the first backup roll 5, and the second backup roll 6 are all installed on the frame 4 and supported by the frame 4.
[0063] The following is the specific embodiment part.
[0064] Embodiment 1:
[0065] As Figures 1 - 3As shown in the figure, in this embodiment, a set of feeding roller groups 1 (correspondingly, one feeding device 3 is configured), a set of continuous rolling roller groups 2, a first backup roll 5, and a second backup roll 6 are configured.
[0066] The feeding roller group 1 is configured with two calendering rollers, namely a first calendering roller 101 and a second calendering roller 102; the continuous rolling roller group 2 is configured with five continuous rolling rollers, including three first continuous rolling rollers 201 and two second continuous rolling rollers 202; the two calendering rollers in the feeding roller group 1 and the five continuous rolling rollers in the continuous rolling roller group 2 are respectively driven by independently arranged motors.
[0067] The first backup roll 5 is in close contact with the first calendering roller 101, and the second backup roll 6 is in close contact with the last first continuous rolling roller 201.
[0068] The system of this embodiment is used for diaphragm rolling, and its working process is as follows:
[0069] The motors in the system drive the corresponding rollers to rotate. The first backup roll 5 is driven to rotate by the first calendering roller 101, and the second backup roll 6 is driven to rotate by the last first continuous rolling roller 201.
[0070] The powder material enters the first roll gap through the feeding device 3, and is calendered and formed by the first calendering roller 101 and the second calendering roller 102 to form a diaphragm.
[0071] Subsequently, the diaphragm enters between the second calendering roller 102 and the first first continuous rolling roller 201 through the third roll gap in sequence and continues to be rolled.
[0072] Then the diaphragm enters the continuous rolling roller group 2 through the first second roll gap, and each continuous rolling roller in the second roller group 2 performs precision rolling and thinning on the diaphragm.
[0073] Finally, the diaphragm is discharged through the last second roll gap.
[0074] Embodiment 2:
[0075] As Figure 4 shown in the figure, in this embodiment, two sets of feeding roller groups 1 (correspondingly, two feeding devices 3 are configured), two sets of continuous rolling roller groups 2, two first backup rolls 5, and two second backup rolls 6 are configured.
[0076] Each feeding roller group 1 is configured with two calendering rollers, namely a first calendering roller 101 and a second calendering roller 102; each continuous rolling roller group 2 is configured with five continuous rolling rollers, including three first continuous rolling rollers 201 and two second continuous rolling rollers 202; the two calendering rollers in each feeding roller group 1 and the five continuous rolling rollers in each continuous rolling roller group 2 are respectively driven by independently arranged motors.
[0077] A set of feeding roller groups 1 is connected to a set of continuous rolling roller groups 2, and a first backing roll 5 and a second backing roll 6 are configured to form a rolling module. The two rolling modules are symmetrically arranged, and a fifth roll gap is formed between the two rolling modules. A metal foil 7 is arranged in the fifth roll gap;
[0078] Each first backing roll 5 is in close contact with the corresponding first calender roll 101, and each second backing roll 6 is arranged at intervals from the corresponding last first continuous rolling roll 201 to form a fourth roll gap. The two second backing rolls 6 are also equipped with independent motors for driving respectively.
[0079] The system of this embodiment is used for double-sided pole piece rolling, and its working process is as follows:
[0080] Two feeding devices 3 respectively feed powder materials, and roll the powder materials into film sheets through the corresponding feeding roller groups 1, and then the film sheets are subjected to precision rolling and thinning through the corresponding continuous rolling roller groups 2;
[0081] Then, in a single set of rolling modules, the film sheets therein sequentially pass through the last first continuous rolling roll 201, the fourth roll gap, the second backing roll 6 and enter the fifth roll gap, and are attached to the corresponding end faces of the metal foil 7;
[0082] The two rolling modules can work independently respectively to complete the production of single-sided pole pieces or double-sided pole pieces.
[0083] The above description is an explanation of the present invention, not a limitation of the invention. The scope defined by the present invention is referred to the claims. Any form of modification can be made within the protection scope of the present invention.
Claims
1. A dry electrode continuous rolling system, characterized in that: The invention comprises at least one group of feed rollers (1), wherein a continuous rolling roller group (2) is arranged at the discharge end of the single group of feed rollers (1), and the single group of feed rollers (1) calenders the powder material into a membrane, and the membrane is continuously rolled and thinned by the corresponding continuous rolling roller group (2) before being discharged; A single set of feed rollers (1) includes several calendering rollers, and the rotation center heights of two adjacent calendering rollers are different. A single set of continuous rolling rollers (2) includes several continuous rolling rollers, and the rotation center heights of two adjacent continuous rolling rollers are different, so that the running angle of the membrane on each roller is less than 180°.
2. A dry electrode continuous rolling system according to claim 1, characterized in that: The rotation center of each calendering roller in the feed roller group (1) is at a different height from the rotation center of each tandem roller in the tandem roller group (2).
3. A dry electrode continuous rolling system according to claim 1, characterized in that: A single feed roller group (1) comprises a first calendering roller (101) and a second calendering roller (102) which are arranged in sequence along the direction from feeding to discharging, a first roller gap is formed between the first calendering roller (101) and the second calendering roller (102), and a rotation center of the second calendering roller (102) is higher than a rotation center of the first calendering roller (101).
4. A dry electrode continuous rolling system as claimed in claim 3, characterized in that: A first backing roller (5) is arranged in front of the first calendering roller (101), and the rotation center of the first backing roller (5) is lower than the rotation center of the first calendering roller (101).
5. A dry electrode continuous rolling system according to claim 1, characterized in that: The single tandem roller group (2) comprises a first tandem roller unit and a second tandem roller unit that cooperate with each other, wherein the first tandem roller unit comprises a plurality of first tandem rollers (201), and the second tandem roller unit comprises a plurality of second tandem rollers (202); A second tandem roller (202) is arranged between two adjacent first tandem rollers (201), so that the first tandem rollers (201) and the second tandem rollers (202) are alternately distributed in sequence, and a second roller gap is formed between the first tandem roller (201) and the adjacent second tandem roller (202).
6. A dry electrode continuous rolling system as claimed in claim 5, characterized in that: The rotation center heights of the first tandem rollers (201) in the first tandem roller unit are equal, and the rotation center heights of the second tandem rollers (202) in the second tandem roller unit are equal.
7. A dry electrode continuous rolling system according to claim 6, characterized in that: The rotation center of the first tandem roller (201) is lower than the rotation center of the second tandem roller (202).
8. A dry electrode continuous rolling system as claimed in claim 6, characterized in that: A second backing roller (6) is arranged at the rear of the single tandem roller group (2), and the rotation center of the second backing roller (6) is higher than the rotation center of the first tandem roller (201) in the first tandem roller unit.
9. A dry electrode continuous rolling system according to claim 1, characterized in that: The roller diameter of each calendering roller in the feed roller group (1) is smaller than the roller diameter of each tandem roller in the tandem roller group (2).
10. The dry electrode continuous rolling system according to claim 1, characterized in that: The feeding end of the single feeding roller group (1) is equipped with a feeding device (3).