Pole piece drying device and pole piece coating system
By designing staggered upper and lower air vents and an isolation layer structure in the electrode drying device, the problems of dark marks and coating cracks in ultra-thin, wide foil electrodes during the electrode coating process were solved, achieving high-quality coating and efficient curing of the electrodes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-20
- Publication Date
- 2026-03-31
AI Technical Summary
During the electrode coating process, ultra-thin, wide foil electrodes are prone to dark marks and coating cracks, which affect the cell capacity, performance and safety, resulting in lower electrode quality.
An electrode drying device is designed, which forms an electrode channel between the upper and lower air chambers and uses hot air circulation with the upper and lower air inlets set alternately to dry the electrode. Combined with the isolation layer on the idler roller to separate the electrode from the idler roller, it ensures uniform heat distribution and reduces local overheating. The isolation layer is made of polytetrafluoroethylene or ceramic fiber material to reduce friction and heat transfer.
It effectively reduces dark marks and coating cracks on electrode sheets, improves the production quality of electrode sheets, reduces scrap rate, and enhances the curing effect of coating slurry and the overall integrity of electrode sheets.
Smart Images
Figure CN224057918U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the pole piece production technical field especially relates to a pole piece drying device. BACKGROUND
[0002] With the rapid growth of new energy automobile and energy storage battery market, the performance and energy density of lithium battery are required higher and higher. The application of ultra-thin and wide foil can meet these demands and help to improve the energy density and safety of the battery. The ultra-thin and wide foil should be used in the electrode coating scene, which has great challenge to the manufacturing process.
[0003] In the related art, the manufacturing enterprise electrode adopts copper foil with width ≤1600mm and thickness ≤6um, and in the electrode coating process, the pole piece is sensitive to temperature, and problems such as dark marks on the surface of the pole piece and cracking of the pole piece coating are prone to occur, thereby affecting the capacity, performance and safety of the battery, and resulting in low pole piece quality. SUMMARY
[0004] Therefore, the utility model aims at providing a pole piece drying device to improve the pole piece quality.
[0005] To achieve the above-mentioned purpose, the technical scheme of the utility model is as follows:
[0006] A pole piece drying device comprises a box body, an upper air chamber, a lower air chamber and a supporting roller arranged in the box body.
[0007] The upper air chamber and the lower air chamber form a pole piece channel, the bottom end of the upper air chamber is provided with a plurality of upper air outlets along the moving direction of the pole piece, and the top end of the lower air chamber is provided with a plurality of lower air outlets along the extension direction of the pole piece channel.
[0008] The supporting roller is covered with an isolation layer and can support the pole piece, and the supporting roller is arranged at intervals with the lower air outlet, and the isolation layer is provided with a through hole penetrating along the radial direction of the supporting roller.
[0009] Further, the ratio k of the air outlet volume of the upper air outlet to the air outlet volume of the lower air outlet is between 1.1 and 1.4.
[0010] Further, the upper air outlet and the lower air outlet are staggered in the vertical direction, and the projection of the supporting roller and the upper air outlet on the pole piece at least partially overlaps.
[0011] Further, the distance S between the top end of the isolation layer and the lower air outlet is between 6mm and 10mm.
[0012] Further, the distance L between the upper air outlet and the pole piece is between 10mm and 15mm.
[0013] Further, the isolation layer is a net structure.
[0014] Further, the through hole is a parallelogram, and one pair of internal angles α is 45°.
[0015] Further, the isolation layer is made of polytetrafluoroethylene.
[0016] Further, the width w of the pole piece is 500mm to 2000mm, and the thickness h is 4.5μm to 8μm.
[0017] Compared with the prior art, the utility model has the following advantages:
[0018] The pole piece drying device, by the pole piece is arranged between the upper air chamber and the lower air chamber and forms the pole piece channel, and the pole piece is conveyed along the extension direction of the pole piece channel, the hot air circulation in the upper air outlet and the lower air outlet realizes the drying of the slurry coating on the pole piece in the pole piece conveying process, and the slurry coating is solidified and firmly attached to the pole piece.
[0019] Meanwhile, the isolation layer on the supporting roller is abutted on the pole piece in the pole piece conveying process, the pole piece is separated from the supporting roller, the pole piece is not directly contacted with the high-temperature supporting roller, the contact area of the pole piece and the isolation layer is reduced due to the through hole on the isolation layer, the heat is more uniform, the pole piece is not deformed due to the high temperature of the supporting roller and the direct contact between the pole piece and the supporting roller, the dark mark of the pole piece in the coating process is reduced, the coating layer of the pole piece slurry is not cracked, and the quality of the pole piece is improved.
[0020] Secondly, the air outlet of the upper air outlet is greater than that of the lower air outlet, the hot air blows the wide pole piece abutted on the supporting roller, the pole piece stably passes through the box body without being scratched by the upper air outlet, the surface of the pole piece is complete without dark mark, and the coating layer of the pole piece slurry is dry and not cracked.
[0021] And, the upper air outlet and the lower air outlet are staggered, the pole piece is continuously dried by the hot air without drying interval, the hot air continuously blows on the pole piece, the drying effect of the coating layer of the coating slurry is improved, the projection of the supporting roller and the upper air outlet on the pole piece at least partially coincides, that is, the supporting roller and the pole piece at least correspond to each other, the hot air of the upper air outlet helps to blow the pole piece to abut on the supporting roller, thereby avoiding the bending of the pole piece due to the lack of supporting of the supporting roller under the pole piece corresponding to the upper air outlet, and the dark mark is reduced.
[0022] In addition, the distance L between the upper air outlet and the pole piece is set to be between 10mm and 15mm, so that the pole piece is not scratched by the upper air outlet, and the quality of the pole piece is improved. The distance S between the top end of the isolation layer and the lower air outlet is set to be between 6mm and 10mm, so that the pole piece is not contacted with the lower air outlet when the upper air outlet blows the pole piece downward, and pole piece damage caused by scratching is avoided. Meanwhile, the distance S is beneficial to the circulation of hot air in the lower air chamber, and heat loss is not caused due to the too large distance.
[0023] Another purpose of the utility model is to provide a pole piece coating system.
[0024] The pole piece coating system has the same beneficial effects as the pole piece drying device described above with respect to the prior art, and will not be described here. BRIEF DESCRIPTION OF DRAWINGS
[0025] The accompanying drawings, which form a part of this description, are included to provide a further understanding of the utility model and are incorporated herein for explanation by reference. The schematic embodiments of the utility model and the description thereof are used to explain the utility model, and do not constitute improper limitation on the utility model. In the drawings:
[0026] Figure 1 Part of the pole piece drying device described in the utility model embodiment is shown in the part of the pole piece drying device described in the utility model embodiment.
[0027] Figure 2 For Figure 1 The part B of the part of the pole piece drying device described in the utility model embodiment is shown in the part of the pole piece drying device described in the utility model embodiment.
[0028] Figure 3 The part of the pole piece drying device described in the utility model embodiment is shown in the part of the pole piece drying device described in the utility model embodiment.
[0029] Figure 4 The isolation layer of the pole piece drying device described in the utility model embodiment is shown in the part of the pole piece drying device described in the utility model embodiment.
[0030] Figure 5 For Figure 4 The part B of the part of the pole piece drying device described in the utility model embodiment is shown in the part of the pole piece drying device described in the utility model embodiment.
[0031] Figure 6 The part of the pole piece drying device described in the utility model embodiment is shown in the part of the pole piece drying device described in the utility model embodiment.
[0032] BRIEF DESCRIPTION OF DRAWINGS
[0033] 1, box; 101, upper air chamber; 102, lower air chamber; 103, supporting roller; 1a, pole piece channel; 1b, upper air outlet; 1c, lower air outlet;
[0034] 2, pole piece;
[0035] 3, isolation layer; 3a, through hole;
[0036] 401, unwinding piece; 402, foil thickness gauge; 403, A-side coating piece; 404, A-side wet film thickness gauge; 405, A-side drying device; 406, A-side dry film thickness gauge; 407, B-side coating piece; 408, B-side wet film thickness gauge; 409, B-side drying device; 410, B-side dry film thickness gauge; 411, winding piece. DETAILED DESCRIPTION
[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.
[0038] In the description of the present application, it should be noted that if the terms indicating the orientation or position relationship such as "upper", "lower", "inner", "outer" appear, they are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, if the terms "first", "second", etc. appear, they are also only for the purpose of description, and cannot be understood as indicating or implying relative importance.
[0039] In addition, in the description of the present application, unless otherwise explicitly limited, the terms "mounting", "connection", "connecting", "connecting piece" should be understood broadly. For example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood in combination with the specific circumstances.
[0040] The present application will be described in detail below with reference to the drawings and in combination with embodiments.
[0041] Embodiment one
[0042] The present embodiment relates to a pole piece drying device to reduce dark marks on the pole piece 2 during the pole piece 2 coating process and cracking of the pole piece 2 slurry coating layer to improve the quality of the pole piece 2.
[0043] Overall structure, refer to Figures 1-6The pole piece drying device in the embodiment comprises a box body 1, an upper air chamber 101, a lower air chamber 102 and a supporting roller 103 arranged in the box body 1; a pole piece channel 1a is formed between the upper air chamber 101 and the lower air chamber 102, a plurality of upper air outlets 1b are arranged at the bottom end of the upper air chamber 101 along the moving direction of the pole piece 2, a plurality of lower air outlets 1c are arranged at the top end of the lower air chamber 102 along the extension direction of the pole piece channel 1a; the supporting roller 103 is coated with an isolation layer 3 and can support the pole piece 2, and the supporting roller 103 is arranged in the lower air chamber 102 and spaced from the lower air outlet 1c; the isolation layer 3 is provided with a through hole 3a penetrating along the radial direction of the supporting roller 103.
[0044] As arranged above, the pole piece 2 is arranged in the pole piece channel 1a formed between the upper air chamber 101 and the lower air chamber 102, and the pole piece 2 is conveyed along the extension direction of the pole piece channel 1a, and the hot air circulation in the upper air outlet 1b and the lower air outlet 1c realizes drying of the slurry coating on the pole piece 2 during the conveying of the pole piece 2, so that the slurry coating is solidified and firmly adhered to the pole piece 2.
[0045] Meanwhile, the pole piece 2 abuts on the isolation layer 3 on the supporting roller 103 during the conveying of the pole piece 2, so that the pole piece 2 is separated from the supporting roller 103, and the pole piece 2 does not directly contact the high-temperature supporting roller 103; and since the through hole 3a is arranged on the isolation layer 3, the contact area of the pole piece 2 and the isolation layer 3 is reduced, and the heat is more uniform, so that the pole piece 2 is prevented from being locally overheated and deformed due to direct contact of the pole piece 2 with the supporting roller 103 at a high temperature; this helps to reduce the dark marks of the pole piece 2 during the coating process of the pole piece 2, and helps to reduce the cracking of the slurry coating of the pole piece 2, so as to improve the product quality of the pole piece 2.
[0046] Based on the above overall introduction, specifically, Figures 1-2 the supporting roller 103 is located in the lower air chamber 102 and is arranged in a plurality of supporting rollers 103 along the extension direction of the pole piece channel 1a, and preferably, the plurality of supporting rollers 103 are distributed at equal intervals in the lower air chamber 102. It is worth noting that when the supporting roller 103 coated with the isolation layer 3 supports the pole piece 2 during drying, the side of the pole piece 2 not coated with the coating slurry abuts on the isolation layer 3, or the coating slurry coating that has been completely solidified abuts on the isolation layer 3. Such an arrangement helps to reduce the scrap rate of the pole piece 2, and at the same time, helps to improve the preparation efficiency of the pole piece 2.
[0047] It is worth noting that in order to maintain the product quality of the pole piece 2 and avoid the situation that the pole piece 2 directly contacts the supporting roller 103 due to wear of the isolation layer 3, the isolation layer 3 can be replaceably sleeved and coated on the outside of the supporting roller 103, for example, the isolation layer 3 can be pasted on the supporting roller 103, when it needs to be replaced, the isolation layer 3 can be scraped off from the supporting roller 103, and a new isolation layer 3 can be re-pasted, so that the isolation layer 3 can be replaced.
[0048] As an implementable manner of the isolation layer 3, the isolation layer 3 is made of polytetrafluoroethylene. The isolation layer 3 made of polytetrafluoroethylene has the characteristics of high chemical stability, high temperature resistance, low friction coefficient, electrical insulation and aging resistance. The high temperature resistance of the isolation layer 3 makes it more durable under the action of hot air, and the high chemical stability of the isolation layer 3 makes it less affected by the coating slurry of the pole piece 2.
[0049] Of course, it can be understood that when the isolation layer 3 is selected, materials that meet the characteristics of wear resistance, high temperature resistance, and low heat transfer coefficient can be selected. As another optional material, ceramic fiber can be selected as the raw material to make the isolation layer 3.
[0050] It can be understood that the isolation layer 3 is implemented by referring to Figures 4-5 The isolation layer 3 can be provided in a mesh structure, and the through holes 3a on the flattened isolation layer 3 can be provided in a parallelogram shape. As a special setting, one pair of internal angles α of the through holes 3a in a parallelogram shape is 45°. Of course, as another optional implementation, one internal angle α of the through holes 3a in a parallelogram shape can be other angles besides 45°.
[0051] By providing the isolation layer 3 in a mesh structure, the support stability of the isolation layer 3 to the pole piece 2 is improved, and the contact area between the isolation layer 3 and the pole piece 2 is minimized, thereby reducing the heat transfer from the high-temperature supporting roller 103 to the pole piece 2 through the isolation layer 3, and reducing the influence of the high-temperature supporting roller 103 on the pole piece 2, thereby improving the quality of the pole piece 2.
[0052] In order to make the pole piece 2 contact the supporting roller 103, the ratio k of the air outlet of the upper air outlet 1b to the air outlet of the lower air outlet 1c is between 1.1 and 1.4. By setting the air outlet of the upper air outlet 1b to be greater than the air outlet of the lower air outlet 1c, the hot air blows the wide pole piece 2 against the supporting roller 103, which facilitates the stable passage of the pole piece 2 through the box 1 without scratching the upper air outlet 1b, so as to facilitate the complete surface of the pole piece 2 without marks, and to keep the coating slurry coating of the pole piece 2 dry and not cracked.
[0053] In order to improve the drying effect of the coating slurry coating on the pole piece 2, the upper air outlet 1b and the lower air outlet 1c are staggered in the vertical direction, and the projection of the supporting roller 103 and the upper air outlet 1b on the pole piece 2 at least partially overlaps.
[0054] As above, referring to Figure 1, by setting the upper air outlet 1b and the lower air outlet 1c staggered distribution, the pole piece 2 is heated by the hot air drying without drying interval, the hot air continuously blowing on the pole piece 2 helps to improve the drying effect of the coating slurry coating. And the upper air outlet 1b and the upper air outlet 1b in the pole piece 2 projection at least partially coincide, that is, the upper air outlet 1b and the pole piece 2 at least a part of the corresponding, so set, the hot air of the upper air outlet 1b helps to blow the pole piece 2 to make it abut on the supporting roller 103, thereby avoiding the pole piece 2 bending due to the absence of the supporting roller 103 under the pole piece 2 corresponding to the upper air outlet 1b, which helps to reduce the generation of dark marks.
[0055] It is worth noting that, in order to avoid the pole piece 2 and the lower air outlet 1c contact caused by the pole piece 2 scratch, the distance S between the top of the isolation layer 3 and the lower air outlet 1c is between 6mm-10mm; That is, the height difference between the highest point of the isolation layer 3 and the lower air outlet 1c in the same plane is set as the distance S.
[0056] Thus, when the upper air outlet 1b blows down the pole piece 2, the pole piece 2 is not easy to contact with the lower air outlet 1c, thereby avoiding the pole piece 2 damage caused by scratching. At the same time, the setting of the distance facilitates the circulation of hot air in the lower air chamber 102, and will not cause heat loss due to the distance being too large. Specifically, the distance S may be, for example, 6mm, 7mm, 8mm, 10mm, etc., preferably, the distance S is set to 8mm.
[0057] Similarly, in order to avoid the pole piece 2 and the lower air outlet 1c contact caused by the pole piece 2 scratch, the distance L between the upper air outlet 1b and the pole piece 2 is between 10mm-15mm. Specifically, the distance L may be, for example, 10mm, 11mm, 13mm, 15mm, etc., preferably, the distance L is set to 13mm. Such a setting makes the pole piece 2 not scratch the upper air outlet 1b, which helps to improve the quality of the pole piece 2.
[0058] Based on the above, it is worth noting that the width w of the pole piece 2 in the embodiment is 500mm-2000mm, and the thickness h is 4.5μm-8μm. Correspondingly, the pole piece drying device can realize drying of the pole piece 2 with a width w of 500mm-2000mm and a thickness h of 4.5μm-8μm.
[0059] The pole piece drying device described in the embodiment of the application, when in use, the pole piece 2 is arranged in the pole piece passage 1a formed between the upper air chamber 101 and the lower air chamber 102, and the pole piece 2 is conveyed along the extension direction of the pole piece passage 1a. The hot air in the upper air outlet 1b and the lower air outlet 1c circulates to dry the slurry coating on the pole piece 2, so that the slurry coating is solidified and firmly attached to the pole piece 2.
[0060] Meanwhile, during the electrode 2 conveying process, the electrode 2 abuts against the isolation layer 3 on the idler roller 103, which can separate the electrode 2 from the idler roller 103, so that the electrode 2 does not directly contact the high-temperature idler roller 103; and because the isolation layer 3 is provided with through holes 3a, the contact area between the electrode 2 and the isolation layer 3 is reduced, and the heat is more uniform, avoiding the local overheating and deformation of the electrode 2 caused by the high temperature of the idler roller 103 and the direct contact between the electrode 2 and the idler roller 103; it helps to reduce the generation of dark marks on the electrode 2 and the cracking of the coating of the electrode 2 slurry during the coating process, so as to improve the production quality of the electrode 2.
[0061] Example 2
[0062] This embodiment relates to an electrode coating system, which is equipped with an electrode drying device as described above.
[0063] By setting up this electrode drying device, it is helpful to reduce the dark marks generated on the electrode 2 and the cracking of the coating of the electrode 2 slurry during the coating process, which helps to improve the production quality of the electrode 2.
[0064] Specifically, the two sides of electrode 2 that need to be coated are designated as side A and side B, as shown in the reference. Figure 6 The electrode coating system includes an unwinding component 401, a foil thickness gauge 402, an A-side coating component 403, an A-side wet film thickness gauge 404, an A-side drying device 405, an A-side dry film thickness gauge 406, a B-side coating component 407, a B-side wet film thickness gauge 408, a B-side drying device 409, a B-side dry film thickness gauge 410, and a rewinding component 411, arranged in a double-layer folding manner and in the conveying direction of the electrode 2.
[0065] It is worth noting that both the A-side drying device 405 and the B-side drying device 409 are the aforementioned electrode drying devices. As an optional arrangement, to prevent the undried side of the electrode 2 from contacting the idler roller 103, the A-side drying device 405 and the B-side drying device 409 are arranged vertically. With this arrangement, when coating and drying the A-side, the uncoated B-side contacts the isolation layer 3 on the idler roller 103. When coating and drying the B-side, the cured A-side contacts the isolation layer 3 on the idler roller 103, thus avoiding the situation where the uncured slurry contacts the isolation layer 3 on the idler roller 103.
[0066] In the electrode coating system described in this embodiment, the rolled electrode foil 2 is unwound by the unwinding unit 401, and the initial thickness of the electrode foil 2 is detected by the foil thickness gauge 402. The A-side coating unit 403 applies a coating slurry to the A-side of the electrode 2, and then the thickness of the coating is detected by the A-side wet film thickness gauge 404. After drying by the A-side drying device 405, the coating slurry coating on the A-side is then detected by the A-side dry film thickness gauge 406 to determine whether the coating slurry coating on the A-side meets the production requirements.
[0067] With the continuous conveying of the pole piece 2, the B face coating device 407 coats the B face of the pole piece 2 with slurry, and then the B face wet film thickness gauge 408 detects the thickness of the coated paint, and then the B face drying device 409 dries, and then the B face dry film thickness gauge 410 detects whether the coating of the A face of the coating slurry meets the production requirements, and finally the winding device 411 is wound.
[0068] The pole piece coating system adopts a double-layer folding form, so that the pole piece 2 foil which is not coated with slurry or the side which is solidified with a coating layer contacts the supporting roller 103 in the pole piece drying device, avoids the situation that the slurry which is not solidified and dried contacts the supporting roller 103, helps to improve the integrity of the pole piece 2 after forming, and helps to improve the quality of the pole piece 2 product.
[0069] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A polar sheet drying device, characterized in that: comprising a box body, and an upper air chamber, a lower air chamber and a supporting roller arranged in the box body; a polar sheet channel is formed between the upper air chamber and the lower air chamber, a plurality of upper air outlets are arranged at the bottom end of the upper air chamber along the moving direction of the polar sheet, and a plurality of lower air outlets are arranged at the top end of the lower air chamber along the extension direction of the polar sheet channel; the supporting roller is covered with an isolation layer and can support the polar sheet, the supporting roller is arranged in the lower air outlet, and the isolation layer is provided with a through hole penetrating in the radial direction of the supporting roller. 2.The polar sheet drying device according to claim 1, characterized in that: the ratio k of the air outlet volume of the upper air outlet to the air outlet volume of the lower air outlet is between 1.1 and 1.
4. 3.The polar sheet drying device according to claim 2, characterized in that: the upper air outlet and the lower air outlet are staggered in the vertical direction, and the projection of the supporting roller on the polar sheet at least partially overlaps the upper air outlet. 4.The polar sheet drying device according to claim 3, characterized in that: the distance S between the top end of the isolation layer and the lower air outlet is between 6 mm and 10 mm. 5.The polar sheet drying device according to claim 3, characterized in that: the distance L between the upper air outlet and the polar sheet is between 10 mm and 15 mm. 6.The polar sheet drying device according to claim 1, characterized in that: the isolation layer is a mesh structure. 7.The polar sheet drying device according to claim 6, characterized in that: the through hole is a parallelogram, and one pair of internal angles α is 45°. 8.The polar sheet drying device according to claim 1, characterized in that: the isolation layer is made of polytetrafluoroethylene. 9.The polar sheet drying device according to any one of claims 1 to 8, characterized in that: the width w of the polar sheet is between 500 mm and 2000 mm, and the thickness h is between 4.5 μm and 8 μm. 10.A polar sheet coating system, characterized in that: the polar sheet coating system is provided with the polar sheet drying device according to any one of claims 1 to 9.