A dry electrode film forming production line
By adopting a variable diameter roller design in the dry electrode film forming production line, the problem of deflection deformation during film rolling in battery electrode manufacturing was solved, achieving uniform film thickness and consistent areal density, and improving electrode quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA INNOVATION AVIATION TECH (WUHAN) CO LTD
- Filing Date
- 2025-06-04
- Publication Date
- 2026-05-26
AI Technical Summary
In the manufacturing process of battery electrodes, especially lithium battery electrodes, the deflection deformation of the rollers due to their identical diameter during film rolling affects the consistency of the transverse surface density of the film, which is a serious problem, especially when the width is greater than 1000mm.
The dry electrode film forming production line includes a frame and symmetrically distributed film forming zones. The film forming zones consist of a support section, a film forming section, and a calendering section. The diameters of the support rollers and film forming rollers decrease from the middle to both ends. The variable diameter roller design increases the rollers' resistance to bending moment and ensures consistent roller gaps.
The variable diameter roller design improves the forming quality of the film and the uniformity of electrode thickness, avoids uneven film thickness, and ensures the consistency of the transverse surface density of the film.
Smart Images
Figure CN224288252U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery manufacturing technology, and in particular to a dry electrode film forming production line. Background Technology
[0002] In the manufacturing process of battery electrodes, especially lithium battery electrodes, film forming and rolling are often required. Specifically, active materials and conductive agents are dry-mixed uniformly, and then a solid binder is added. Under the fibrous action of the binder, a self-supporting film is formed, and finally, the film is rolled and rolled onto the surface of the current collector. During film forming and rolling, the rollers have the same diameter throughout the axial direction. During film rolling, the rollers undergo deflection deformation under gravity. When the width of the dry coating rollers is greater than 1000 mm, the roller deformation reaches 14 μm, severely affecting the consistency of the transverse areal density of the film.
[0003] Therefore, there is an urgent need for a dry electrode film formation production line to solve the above-mentioned technical problems. Utility Model Content
[0004] The purpose of this invention is to propose a dry electrode film forming production line that can avoid uneven film thickness and ensure consistent transverse surface density of the film.
[0005] To achieve this objective, the present invention adopts the following technical solution:
[0006] A dry electrode film forming production line includes a frame and two symmetrically distributed film forming zones. Along the film conveying direction, the film forming zones sequentially include a support section, a film forming section, and a calendering section. The support section has at least one support roller, the film forming section has two film forming rollers, and the calendering section has multiple calendering rollers. The support roller, the film forming roller, and the calendering roller are all rotatably mounted on the frame. Among the support roller and the film forming roller, the diameter of at least one roller decreases from the middle to both ends.
[0007] This utility model has at least the following beneficial effects:
[0008] At least one of the support rollers and the film-forming rollers has a diameter that decreases from the middle to both ends; that is, at least one roller is a variable-diameter roller. This ensures that the diameter of at least one of the support rollers and the film-forming rollers changes from the middle to both ends. Since the roller is subjected to a force F at both ends, the bending moment in the middle is greater than that at both ends. However, the larger diameter in the middle increases the resistance to bending moment, making the deformation in the middle not significantly different from that at the ends. The roller does not experience significant bending before and after being subjected to force, thus ensuring that the gap between the support roller and the film-forming roller is almost the same in the axial direction. This results in a uniform thickness of the extruded film in the width direction, guaranteeing consistent transverse surface density. This design improves the overall forming quality of the film, thereby improving the quality of the electrodes obtained from the film preparation. Attached Figure Description
[0009] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.
[0010] Figure 1 A side view of a dry electrode film forming production line provided in an embodiment of this utility model;
[0011] Figure 2 A first front view of the arrangement of rollers in the film-forming zone of a dry electrode film-forming production line provided in an embodiment of this utility model;
[0012] Figure 3 A second front view of the rollers in the film-forming zone of a dry electrode film-forming production line provided in an embodiment of this utility model;
[0013] Figure 4 A third front view of the rollers in the film-forming zone of the dry electrode film-forming production line provided in this embodiment of the utility model;
[0014] Figure 5 A first schematic diagram of the first busbar provided in an embodiment of this utility model;
[0015] Figure 6 A second schematic diagram of the first busbar provided in an embodiment of this utility model;
[0016] Figure 7 A third schematic diagram of the first busbar provided in an embodiment of this utility model;
[0017] Figure 8 The fifth front view of the rollers in the film-forming zone of the dry electrode film-forming production line provided in this embodiment of the utility model;
[0018] Figure 9 This is a first schematic diagram of the second busbar provided in an embodiment of the present utility model;
[0019] Figure 10 This is a second schematic diagram of the second busbar provided in an embodiment of the present utility model.
[0020] In the picture:
[0021] 1. Support section; 11. Support roller; 2. Film forming section; 21. Film forming roller; 3. Calendering section; 31. Calendering roller; 4. First generatrix; 41. First segment; 42. Second segment; 43. Third segment; 44. Fourth segment; 5. Second generatrix; 51. Fifth segment; 52. Sixth segment; 53. Seventh segment; 6. Composite zone; 61. Composite roller; 100. Central axis. Detailed Implementation
[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.
[0023] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0025] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.
[0026] This invention provides a dry electrode film forming production line that can avoid thinner edges of the film and ensure that the overall thickness of the film is consistent.
[0027] like Figures 1-4 , Figure 8 As shown, the dry electrode film forming production line includes a frame and two symmetrically distributed film forming zones. Along the film conveying direction, the film forming zones sequentially include a support section 1, a film forming section 2, and a calendering section 3. The support section 1 has at least one support roller 11, the film forming section 2 has two film forming rollers 21, and the calendering section 3 has multiple calendering rollers 31. The support roller 11, the film forming roller 21, and the calendering roller 31 are all rotatably mounted on the frame. Among the support roller 11 and the film forming roller 21, the diameter of at least one roller decreases from the middle to both ends.
[0028] The diameter of at least one of the support roller 11 and the film forming roller 21 decreases from the middle to both ends, that is, at least one roller is a variable diameter roller, so that the diameter of at least one of the support roller 11 and the film forming roller 21 changes from the middle to both ends. Since the roller is subjected to force F at both ends, the bending moment in the middle of the roller is greater than that at both ends. However, the diameter in the middle is larger, which can increase the ability to resist bending moment, so that the deformation in the middle is not much different from that at both ends. The roller will not produce large bending before and after being subjected to force, so that the gap between the support roller 11 and the film forming roller 21 is almost the same in the axial direction, thereby making the extruded film uniform in thickness in the width direction and ensuring the consistency of the transverse surface density of the film.
[0029] In the multiple rollers including the support roller 11, the film forming roller 21, and the calendering roller 31, the central axes of adjacent rollers are located on different horizontal planes. This allows the roller located below to provide some support to the roller located above, thereby reducing the pressure exerted on the adjacent rollers and reducing the amount of flexible deformation of some rollers. This arrangement can improve the overall forming quality of the film and thus improve the quality of the electrode obtained from the film preparation.
[0030] The dry electrode film forming production line also includes a composite zone 6, which includes two composite rollers 61. The films obtained from the two symmetrically distributed film forming zones on both sides of the current collector are rolled by the composite rollers 61 to obtain electrode sheets. Since the films obtained from the film forming zones have the same thickness, the electrode sheets obtained by the dry electrode film forming production line provided by this utility model also have the same thickness, which can avoid the edge thickness reduction of the electrode sheets and ensure the consistency of the surface density on both sides of the electrode sheets.
[0031] It should be noted that the film-forming roller 21 and the support roller 11 in the same film-forming area are both installed in the same bearing housing to ensure the accuracy of the installation of the film-forming roller 21 and the support roller 11.
[0032] The support roller 11, film forming roller 21, composite roller 61 and calendering roller 31 all include a working part and a support part. The working part is provided with support parts at both ends, and the support parts rotatably mount the working part to the bearing seat.
[0033] In some embodiments, such as Figure 1 and Figure 2 As shown, there is one support roller 11, and the diameter of the support roller 11 decreases from the middle to both ends. For example, the diameter of the support roller 11 decreases uniformly from the middle to both ends. Since the support roller 11 is subjected to a force F at both ends, the bending moment in the middle of the support roller 11 is greater than that at both ends. However, the diameter in the middle is larger, which increases the ability to resist bending moment, so that the deformation in the middle is not much different from that at both ends. The support roller 11 will not produce large bending before and after being subjected to force, so that the gap between the support roller 11 and the film forming roller 21 is almost the same in the axial direction, ensuring that the extruded film has a uniform thickness in the width direction.
[0034] In other embodiments, the diameter of the film-forming roller 21 adjacent to the support roller 11 decreases from the middle to both ends. Specifically, as... Figure 8 As shown, the diameter of the film-forming roller 21 decreases uniformly from the middle to both ends. Since the film-forming roller 21 is subjected to force F at both ends, the bending moment in the middle of the film-forming roller 21 is greater than that at both ends. However, the diameter in the middle is large, which increases the ability to resist bending moment, so that the deformation in the middle is not much different from that at both ends. The straightness of the film-forming roller 21 does not change much before and after being subjected to force, so that the gap between the support roller 11 and the film-forming roller 21 is almost the same in the axial direction, thus making the extruded film uniform in thickness in the width direction.
[0035] In some embodiments, such as Figure 4 As shown, there are two or more support rollers 11, and the diameter of the support rollers 11 adjacent to the film-forming roller 21 decreases from the middle to both ends. That is, the diameter of the support rollers 11 adjacent to the film-forming roller 21 decreases from the middle to both ends. Specifically, the diameter of the support rollers 11 decreases uniformly from the middle to both ends, or the diameter of the support rollers 11 decreases in a stepwise manner from the middle to both ends. Since the support rollers 11 are subjected to force F at both ends, the bending moment in the middle of the support rollers 11 is greater than that at both ends. However, the diameter in the middle is larger, which increases the ability to resist bending moment, so that the deformation in the middle is not much different from the deformation at both ends. The straightness of the support rollers 11 does not change much before and after being subjected to force (or in other words, it will not produce a large bend), while the diameter of the corresponding film-forming roller 21 is a constant value. In this way, after the film-forming roller 21 adjacent to the support rollers 11 deforms, the support rollers 11 can adapt to the deformation, so that the gap between the support rollers 11 and the film-forming roller 21 is almost the same in the axial direction, thereby making the extruded film uniform in thickness in the width direction.
[0036] In some embodiments, among the adjacent support rollers 11 and film-forming rollers 21, only one roller has a diameter that decreases from the middle to both ends. This arrangement ensures uniform film thickness and avoids uneven film thickness at both ends caused by the diameters of both the adjacent support rollers 11 and film-forming rollers 21 decreasing.
[0037] In some embodiments, the lengths of the support roller 11 and the film-forming roller 21 range from 1200mm to 1300mm. For example, the lengths of the support roller 11 and the film-forming roller 21 can be 1200mm, 1210mm, 1220mm, 1230mm, 1240mm, 1250mm, 1260mm, 1270mm, 1280mm, 1290mm, or 1300mm. No specific limitation is made in this embodiment. When the length of the support roller 11 and the film-forming roller 21 is 1200mm, the width of the film can be guaranteed. When the length of the support roller 11 and the film-forming roller 21 is 1300mm, the deformation at the ends of the film can be reduced while ensuring the width of the film.
[0038] In some embodiments, the diameter of the support roller 11 ranges from 400mm to 600mm. For example, the diameter of the support roller 11 can be selected as 400mm, 410mm, 420mm, 430mm, 440mm, 450mm, 460mm, 470mm, 480mm, 490mm, 500mm, 510mm, 520mm, 530mm, 540mm, 550mm, 560mm, 570mm, 580mm, 590mm, 600mm, 640mm, 670mm, or 700mm. No specific limitation is made in this embodiment.
[0039] In some embodiments, the diameter of the film-forming roller 21 ranges from 150mm to 250mm. For example, the diameter of the film-forming roller 21 can be selected as 150mm, 160mm, 170mm, 180mm, 190mm, 200mm, 210mm, 220mm, 230mm, 240mm, 250mm, 270mm, 290mm or 300mm. No specific limitation is made in this embodiment.
[0040] In some embodiments, the diameter of the calendering roll 31 ranges from 400mm to 600mm. For example, the diameter of the calendering roll 31 is 400mm, 410mm, 420mm, 430mm, 440mm, 450mm, 460mm, 470mm, 480mm, 490mm, 500mm, 510mm, 520mm, 530mm, 540mm, 550mm, 560mm, 570mm, 580mm, 590mm, or 600mm. No specific limitation is made in this embodiment.
[0041] In order to thin the film by rolling to obtain a film that meets the thickness requirements, the number of calendering rolls 31 in each film-forming zone is 5 to 9. For example, the number of calendering rolls 31 is 5, 6, 7, 8, or 9. When the number of calendering rolls 31 is 5, the thickness of the film can be guaranteed, while when the number of calendering rolls 31 is 9, the thickness of the film can be more uniform.
[0042] In some embodiments, the working portion of the support roller 11 is formed by rotating the first generatrix 4 360° around the central axis 100, such as... Figure 5 As shown, the first busbar 4 includes a first line segment 41 and a second line segment 42 located at both ends of the first line segment 41. The first line segment 41 is an arc-shaped line segment, and the second line segment 42 is a straight line segment. The two second line segments 42 are parallel and perpendicular to the central axis 100. From the middle to both ends, the distance between the arc-shaped line segment and the central axis 100 continuously decreases.
[0043] In other embodiments, the working portion of the support roller 11 is formed by rotating the first generatrix 4 360° around the central axis 100, such as... Figure 6 As shown, the first busbar 4 includes a first segment 41, a second segment 42, a third segment 43, and a fourth segment 44. The two ends of the first segment 41 are connected to the second segment 42 through the third segment 43 and the fourth segment 44. The two ends of the third segment 43 are connected to the first segment 41 and the fourth segment 44 respectively. The two ends of the fourth segment 44 are connected to the third segment 43 and the second segment 42 respectively. The first segment 41 is an arc-shaped segment or a straight segment, and the second segment 42 is a straight segment. The two second segments 42 are parallel and perpendicular to the central axis 100. The third segment 43 is a straight segment, and the fourth segment 44 is an arc-shaped segment or a straight segment. From the first segment 41 to the second segment 42, the distance between the fourth segment 44 and the central axis 100 decreases. When the first line segment 41 is a straight line segment, the first line segment 41 is set parallel to the central axis 100. When the fourth line segment 44 is a straight line segment, the fourth line segment 44 is set parallel to the central axis 100 or at an angle to the central axis 100. From the first line segment 41 to the second line segment 42, the distance between the fourth line segment 44 and the central axis 100 continuously decreases.
[0044] In other embodiments, the working portion of the support roller 11 is formed by rotating the first generatrix 4 360° around the central axis 100, such as... Figure 7 As shown, the first generatrix 4 includes a first segment 41, a second segment 42, and a fourth segment 44. From the first segment 41 towards the second segment 42, the distance between the fourth segment 44 and the central axis 100 continuously decreases. The fourth segment 44 is either an arc-shaped segment or a straight segment. From the first segment 41 towards the second segment 42, the distance between the fourth segment 44 and the central axis 100 shows a decreasing trend. When the first segment 41 is a straight segment, it is parallel to the central axis 100. When the fourth segment 44 is a straight segment, it is either parallel to the central axis 100 or forms an angle with it. From the first segment 41 towards the second segment 42, the distance between the fourth segment 44 and the central axis 100 continuously decreases.
[0045] In some embodiments, the working portion of the film-forming roller 21 is formed by rotating the second generatrix 5 360° around the central axis 100, such as Figure 9 and Figure 10 As shown, the second busbar 5 includes a fifth segment 51, two sixth segments 52, and two seventh segments 53. The two ends of the fifth segment 51 are connected to the seventh segments 53 through the sixth segments 52. The fifth segment 51 is parallel to the central axis 100. The two seventh segments 53 are parallel and perpendicular to the central axis 100. The two straight segments are parallel. The sixth segment 52 is a straight segment or an arc segment. From the fifth segment 51 to the seventh segment 53, the distance between the sixth segment 52 and the central axis 100 decreases continuously.
[0046] The mounting portion of the support roller 11 is located at both ends of the working portion of the support roller 11, and the mounting portion of the film forming roller 21 is located at both ends of the working portion of the film forming roller 21. Both the mounting portion of the support roller 11 and the mounting portion of the film forming roller 21 are formed by rotating the mounting line segment 360° around the central axis 100.
[0047] In some embodiments, such as Figure 10 As shown, the length of the fifth line segment 51 is L1. The structure formed by rotating the fifth line segment 51 360° around the central axis is always in contact with the film. The length of the working part of the film roller 21 is L2, where L1 = (60%~90%)L2. For example, L1 = 60%L2, L1 = 70%L2, L1 = 80%L2 or L1 = 90%L2. No specific setting is made in this embodiment. When L1 = 60%L2, the uniformity of the thickness of the obtained film can be improved, while when L1 = 90%L2, the width of the obtained film can be guaranteed.
[0048] Furthermore, the diameter of the film-forming roller 21 varies from 0.005 mm to 0.05 mm. More specifically, the diameter of the film-forming roller 21 varies from 0.005 mm to 0.025 mm. For example, the diameter of the film-forming roller 21 varies from 0.005 mm, 0.01 mm, 0.015 mm, 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, or 0.05 mm. No specific limitation is made in this embodiment.
[0049] Furthermore, the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.
Claims
1. A dry electrode film production line, characterized by, The film forming device comprises a rack and two symmetrical film forming areas, which are sequentially provided with a supporting section (1), a film forming section (2) and a calendering section (3) along the transmission direction of the film sheet, the supporting section (1) has at least one supporting roller (11), the film forming section (2) has two film forming rollers (21), and the calendering section (3) has a plurality of calendering rollers (31), the supporting roller (11), the film forming roller (21) and the calendering roller (31) are rotatably mounted on the rack, and the diameter of at least one roller among the supporting roller (11) and the film forming roller (21) decreases from the middle to the two ends.
2. The dry electrode film formation line according to claim 1, characterized by The number of the supporting roller (11) is one, and the diameter of the supporting roller (11) decreases from the middle to the two ends.
3. The dry electrode film formation line according to claim 1, characterized by The diameter of the film forming roller (21) adjacent to the supporting roller (11) decreases from the middle to the two ends.
4. The dry electrode film formation line according to claim 1, characterized by The number of the supporting roller (11) is more than two, and the diameter of the supporting roller (11) adjacent to the film forming roller (21) decreases from the middle to the two ends.
5. The dry electrode film formation line according to any one of claims 2 to 4, characterized in that, Among the supporting roller (11) and the film forming roller (21) arranged adjacently, only the diameter of one roller decreases from the middle to the two ends.
6. The dry electrode film formation line according to any one of claims 1 to 4, characterized by, The length of the supporting roller (11) and the film forming roller (21) ranges from 1200 mm to 1300 mm; and / or, The diameter of the supporting roller (11) ranges from 400 mm to 700 mm; and / or, The diameter of the film forming roller (21) ranges from 150 mm to 300 mm; and / or, The diameter of the calendering roller (31) ranges from 400 mm to 600 mm.
7. The dry electrode film formation line according to any one of claims 1 to 4, characterized by The number of the calendering roller (31) of each film forming area ranges from 5 to 9.
8. The dry electrode film formation line according to any one of claims 1 to 4, characterized by The working part of the supporting roller (11) is formed by rotating the first generatrix (4) around the center axis (100) by 360°, the first generatrix (4) comprises a first line segment (41) and a second line segment (42) located at both ends of the first line segment (41), the first line segment (41) is an arc line segment, the second line segment (42) is a straight line segment, and the two second line segments (42) are parallel and arranged perpendicularly to the center axis (100).
9. The dry electrode film formation line according to any one of claims 1 to 4, characterized by, The working part of the support roller (11) is formed by rotating a first generatrix (4) 360° around a central axis (100). The first generatrix (4) includes a first segment (41), a second segment (42), a third segment (43), and a fourth segment (44). The two ends of the first segment (41) are connected to the second segment (42) through the third segment (43) and the fourth segment (44). The two ends of the third segment (43) are connected to the first segment (41) and the fourth segment (44) respectively. The fourth segment (44) has... The two ends are respectively connected to the third line segment (43) and the second line segment (42). The first line segment (41) is an arc-shaped line segment or a straight line segment, and the second line segment (42) is a straight line segment. The two second line segments (42) are parallel and perpendicular to the central axis (100). The third line segment (43) is a straight line segment, and the fourth line segment (44) is an arc-shaped line segment or a straight line segment. From the first line segment (41) to the second line segment (42), the distance between the fourth line segment (44) and the central axis (100) tends to decrease.
10. The dry electrode film formation line according to any one of claims 1 to 4, characterized by, The working part of the support roller (11) is formed by rotating the first generatrix (4) around the central axis (100) by 360°. The first generatrix includes a first segment (41), a second segment (42) and a fourth segment (44). From the first segment (41) to the second segment (42), the distance between the fourth segment (44) and the central axis (100) decreases continuously.
11. The dry electrode film formation line according to any one of claims 1 to 4, characterized by The working part of the film-forming roller (21) is formed by rotating the second generatrix (5) 360° around the central axis (100). The second generatrix (5) includes a fifth segment (51), two sixth segments (52) and two seventh segments (53). The two ends of the fifth segment (51) are connected to the seventh segments (53) through the sixth segments (52). The two seventh segments (53) are arranged in parallel and perpendicular to the central axis (100). The fifth segment (51) is arranged in parallel with the central axis (100). The sixth segment (52) is a straight line segment or an arc segment. From the fifth segment (51) to the seventh segment (53), the distance between the sixth segment (52) and the central axis (100) decreases continuously.
12. The dry electrode film formation line according to claim 11, characterized by The length of the fifth line segment (51) is L1, and the length of the working part of the film forming roller (21) is L2, wherein L1 = (60% to 90%)L2.
13. The dry electrode film formation production line according to any one of claims 1 to 4, characterized by, Among the multiple rollers, including the support roller (11), the film forming roller (21), and the calendering roller (31), the central axes of adjacent rollers are located on different horizontal planes.