Coating die head and back roller structure capable of reducing slurry resistance
By tilting the extrusion coating die head in the extrusion coating machine and adjusting the slurry channel structure, the problems of flipping and film surface unevenness caused by the back roller reaction force during the coating process are solved, and the film is realized The effect of uniform surface thickness and scratch-free.
Patent Information
- Application Number
- CN202420092764.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-15
- Publication Date
- 2025-01-07
- Estimated Expiration
- 2034-01-15
AI Technical Summary
In the existing extrusion coating machine, the slurry is easily flipped by the reaction force of the back roller during the coating process, resulting in intermittent ripples and uneven thickness of the film surface, especially when there are fine particles, the film surface scratches are easily seen. .
An inclined extrusion coating die is designed, with the slurry extrusion outlet higher than the inlet, and by adjusting the angle of the slurry channel and the outlet center height, an oblique thrust and diffusion angle is formed to reduce the slurry and back The resistance of the roller ensures smooth flow of slurry.
It effectively reduces the flip and resistance of the slurry, ensures uniform thickness of the film surface, avoids the occurrence of scratches on the film surface, and improves the coating quality of lithium-ion batteries.
Smart Images
Figure CN222306259U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to an extrusion coating machine, in particular to a coating die head and a back roller structure for reducing slurry resistance. Background Art
[0002] During the production of lithium-ion batteries, the slurry is directly coated on the current collector using an extrusion coating method. The quality of the coating process directly determines the performance of the lithium-ion battery.
[0003] In the existing extrusion coating machine, the extrusion coating die head and the coating backing roller are horizontally at the same height, and form a 90° angle with the vertical tangent of the backing roller. When applying high-volatile solvent slurry, the slurry is subjected to the reaction force of the backing roller, and the direction of the reaction force is opposite to the direction of the slurry, so that the slurry flips toward the extrusion coating die head, and the intermittent lateral ripples on the film surface are prominent, resulting in uneven film thickness. When there are fine particles in the slurry, due to the small gap of the slurry extrusion outlet, it is easier to get stuck between the slurry extrusion outlet and the backing roller under the reaction force of the backing roller, causing scratches on the film surface.
[0004] Therefore, the utility model provides a coating die head and back roller structure for reducing slurry resistance to solve the problems raised in the above background technology. Utility Model Content
[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0006] A coating die and backing roller structure for reducing slurry resistance comprises an extrusion coating die and a coating backing roller, wherein a slurry channel is arranged inside the extrusion coating die, and a slurry inlet and a slurry extrusion outlet connected to the slurry channel are respectively arranged at two ends of the extrusion coating die, the coating backing roller is located beside the extrusion coating die and close to the slurry extrusion outlet, the extrusion coating die is arranged obliquely, and the slurry extrusion outlet is higher than the slurry inlet.
[0007] A further solution is as follows: the plane in the slurry channel that is equidistant from the upper and lower side walls is plane α, the plane vertically tangent to the coating back roller is plane β, and the angle a between plane α and plane β is an obtuse angle, preferably 91.5°.
[0008] A further solution is as follows: the coating back roller is tangent to the plane β at the tangent line l, the center of the slurry extrusion outlet is higher than the tangent line l, and the height difference is h, 0﹤h﹤2cm.
[0009] Compared with the prior art, the beneficial effects of the utility model are:
[0010] 1. The extrusion coating die head is tilted, and the slurry extrusion outlet is higher than the slurry inlet, so that the reaction force of the backing roller is not in the same straight line as the direction of the slurry, but forms an oblique upward thrust, so that the movement direction of the slurry coming out of the slurry extrusion outlet is the same as the direction of the substrate on the coating backing roller.
[0011] 2. The center of the slurry extrusion outlet is slightly higher than the tangent line l, so that a diffusion angle of discharge is formed between the extrusion coating die head and the coating backing roller, so that the slurry and particles are easily brought out to avoid scratches on the membrane surface. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In order to facilitate understanding by those skilled in the art, the present invention is further described below in conjunction with the accompanying drawings.
[0013] Figure 1 It is a schematic diagram of the structure of the utility model;
[0014] Figure 2 It is a schematic diagram of the slurry direction;
[0015] Figure 3 Schematic diagram of particle orientation;
[0016] Figure 4 It is the cross-sectional view of the membrane surface;
[0017] Figure 5 Schematic diagram of the membrane surface.
[0018] In the figure: 1-extrusion coating die head; 11-slurry channel; 12-slurry extrusion outlet; 2-coating backing roller; 3-particles. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model, that is, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.
[0020] Therefore, the following detailed description of the embodiments of the utility model provided in the accompanying drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.
[0021] See also Figure 1In an embodiment of the utility model, a coating die and backing roller structure for reducing slurry resistance includes an extrusion coating die 1 and a coating backing roller 2, wherein a slurry channel 11 is provided in the extrusion coating die 1, and a slurry inlet and a slurry extrusion outlet 12 connected to the slurry channel 11 are respectively provided at both ends of the extrusion coating die 1, and the coating backing roller 2 is located beside the end of the extrusion coating die 1 and close to the slurry extrusion outlet 12, and the coating backing roller 2 is arranged parallel to the slurry extrusion outlet 12. The extrusion coating die 1 is arranged obliquely, and the slurry extrusion outlet 12 is higher than the slurry inlet.
[0022] In the figure, the plane in the slurry channel 11 that is equidistant from the upper and lower side walls is plane α, the plane that is vertically tangent to the coating back roller 2 is plane β, and the angle a between plane α and plane β is an obtuse angle. The coating back roller 2 is tangent to plane β at the tangent line l, and the center of the slurry extrusion outlet 12 is higher than the tangent line l, with a height difference of h, 0﹤h﹤2cm. That is, the extrusion coating die head 1 is slightly tilted upward compared to the coating back roller 2, so that the slurry extrusion outlet 12 is no longer directly facing the tangent line l, but facing above the tangent line l, so that the reaction force of the back roller 2 is not in the same straight line as the direction of the slurry, but forms an oblique upward thrust, which reduces the slurry flipping and is quickly carried away with the movement of the substrate, playing an auxiliary dispersion role, so that the lateral coating thickness of the membrane surface is uniform, please refer to Figure 2 . Also, see Figure 3 The center of the slurry extrusion outlet 12 is slightly higher than the tangent line 1, so that a diffusion angle of discharge is formed between the extrusion coating die head 1 and the coating backing roller 2, and the gap distance is increased to prevent the slurry from rolling up and depositing at the slurry extrusion outlet 12, so that the slurry and particles can be easily discharged without particle jamming, thereby avoiding scratches on the membrane surface.
[0023] The angle a is preferably 91.5°. This angle can make the movement direction of the slurry coming out of the slurry extrusion outlet the same as the direction of the substrate on the coating backing roller, so that the transverse coating thickness of the film surface is uniform, only a single particle point is formed, no scratches will appear, and the production quality is improved. For the cross-sectional view of the film surface, please refer to Figure 4 , Figure 5 The membrane face surface is shown.
[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0025] The above contents are merely examples and explanations of the structure of the utility model. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the utility model or exceed the scope defined in the claims, they should all fall within the protection scope of the utility model.
Claims
1. A coating die head and backing roller structure for reducing slurry resistance, characterized in that: The invention comprises an extrusion coating die head and a coating backing roller. A slurry channel is arranged in the extrusion coating die head. A slurry inlet and a slurry extrusion outlet connected to the slurry channel are arranged at two ends of the extrusion coating die head respectively. The coating backing roller is located beside the extrusion coating die head and close to the slurry extrusion outlet. The extrusion coating die head is arranged obliquely, and the slurry extrusion outlet is higher than the slurry inlet.
2. A coating die head and backing roller structure for reducing slurry resistance according to claim 1, characterized in that: The plane in the slurry channel that is equidistant from the upper and lower side walls is plane α, the plane that is vertically tangent to the coating back roller is plane β, and the angle a between plane α and plane β is an obtuse angle.
3. A coating die head and backing roller structure for reducing slurry resistance according to claim 2, characterized in that: The angle a is 91.5°.
4. A coating die head and backing roller structure for reducing slurry resistance according to claim 2, characterized in that: The coating back roller is tangent to the plane β at the tangent line l, the center of the slurry extrusion outlet is higher than the tangent line l, and the height difference is h, 0﹤h﹤2cm.