CN114643163A

CN114643163A - Coating die head and coating device

Info

Publication number: CN114643163A
Application number: CN202011499022.9A
Authority: CN
Inventors: 郭金鑫; 雷松; 李华标; 田冠楠
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2022-06-21
Anticipated expiration: 2040-12-17
Also published as: CN114643163B

Abstract

The application discloses coating die head and coating unit. The coating die head comprises a die head body, wherein a slit for flowing coating slurry is arranged in the die head body, and the slit is provided with an outlet for flowing out the coating slurry; the two opposite inner walls of the outlet of the slit in the width direction are respectively provided with a first chamfer and a second chamfer which are the same.

Description

Coating die head and coating device

Technical Field

The application relates to the technical field of battery production equipment, in particular to a coating die head and a coating device.

Background

In recent years, with the development of science and technology and the increasing of the popularization of new energy automobiles, the application of the lithium ion battery is more and more extensive. The pole piece is a key component of the lithium ion battery, and coating is one of very important links in the production process of the pole piece. When the existing coating die head is used for coating, the coating slurry has large speed and direction change when flowing out, a flow field is not easy to be stable, and a dead zone of the flow field is easy to form, so that the slurry is settled and blocked after being agglomerated, and the defects of coating, scribing and the like are caused.

In view of the above, a new technical solution is needed to solve the above technical problems.

Disclosure of Invention

An object of the present application is to provide a new solution for a coating die and a coating apparatus.

According to a first aspect of the present application, there is provided a coating die comprising:

a die body in which a slit for flowing a coating slurry is provided, the slit having an outlet for flowing out the coating slurry; the two opposite inner walls of the outlet of the slit in the width direction are respectively provided with a first chamfer and a second chamfer which are the same.

Optionally, the first chamfer and the second chamfer are fillets, and the radius of the fillet of the first chamfer is the same as the radius of the fillet of the second chamfer.

Optionally, the radius of the rounded corner of the first chamfer and the radius of the rounded corner of the second chamfer are both R, and R is greater than or equal to 0.5mm and less than or equal to 2.5 mm.

Optionally, the die body comprises a first die block having a first surface and a second die block having a second surface, the slot being formed between the first surface and the second surface;

the first module has a third surface intersecting the first surface at the outlet, the second module has a fourth surface intersecting the second surface at the outlet, the third surface is disposed flush with the fourth surface; the first chamfer is formed between the first surface and the third surface; the second chamfer is formed between the second surface and the fourth surface.

Optionally, the first surface is disposed obliquely to the third surface, the second surface is disposed obliquely to the fourth surface, and the first surface is parallel to the second surface.

Optionally, the angle at which the first surface is inclined relative to the third surface and the angle at which the second surface is inclined relative to the fourth surface are both Q, and 50 DEG-Q < 70 deg.

Optionally, the die head body further includes a shim, the shim is clamped between the first die block and the second die block, the shim has a fifth surface and a sixth surface that are opposite to each other, the first surface is attached to the fifth surface, the second surface is attached to the sixth surface, a notch that is recessed in a direction away from the outlet is formed in the shim, the notch penetrates through the fifth surface and the sixth surface, and the first surface and the second surface respectively cover the notch to form the slit.

Optionally, the gasket further has a seventh surface connected between the fifth surface and a sixth surface, the seventh surface is respectively butted with the third surface and the fourth surface, and the seventh surface is arranged flush with the third surface and the fourth surface.

Optionally, a third chamfer is arranged between the seventh surface and the fifth surface, and the third chamfer is the same as the first chamfer; a fourth chamfer is provided between the seventh surface and the sixth surface, the fourth chamfer being the same as the second chamfer.

According to a second aspect of the present application, there is provided a coating apparatus comprising a coating die according to the first aspect.

The technical scheme adopted by the application can achieve the following beneficial effects:

in the coating die head provided by the embodiment of the application, the same first chamfer and the same second chamfer are arranged on the two opposite inner walls at the outlet of the slit, so that the coating slurry can be smoothly transferred onto a base material, the residence time of the coating slurry at the outlet is reduced, the flowing dead zone of the coating slurry at the outlet is obviously improved, the agglomeration and sedimentation of the coating slurry are reduced, the risk of forming large particles by the agglomeration and sedimentation of the coating slurry is reduced, and the probability of generating defects such as coating scribing lines is reduced.

Further features of the present application and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which is to be read in connection with the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application.

FIG. 1 is a schematic cross-sectional view of the overall structure of a coating die according to one embodiment of the present application;

FIG. 2 is an enlarged schematic view at A in FIG. 1;

FIG. 3 is a schematic illustration of an exploded structure of a coating die according to one embodiment of the present application;

FIG. 4 is a schematic diagram of a shim in a coating die according to one embodiment of the present application;

fig. 5 is an enlarged schematic view at B in fig. 4.

Detailed Description

Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be discussed further in subsequent figures.

Referring to fig. 1-2, according to one embodiment of the present application, a coating die is provided. The coating die head comprises a die head body, wherein a slit 101 for coating slurry to flow is arranged in the die head body, and the slit 101 is provided with an outlet 1011 for coating slurry to flow out; the outlet 1011 of the slit 101 is provided with the same first chamfer 132 and second chamfer 332 on the two inner walls opposite to each other in the width direction.

In the coating die provided in the embodiment of the present application, the coating slurry flows in the slit 101 and flows out through the outlet 1011 and is then sprayed on the substrate 4. In the process, because the two opposite inner walls of the outlet 1011 of the slit 101 in the width direction are respectively provided with the first chamfer 132 and the second chamfer 332, and the first chamfer 132 and the second chamfer 332 are the same, the first chamfer 132 and the second chamfer 332 can help the coating slurry to smoothly transit onto the base material 4, the residence time of the coating slurry at the outlet 1011 is reduced, the flowing 'dead zone' of the coating slurry at the outlet 1011 is obviously improved, the occurrence of agglomeration and sedimentation of the coating slurry is reduced, the risk of forming large particles by the agglomeration and sedimentation of the coating slurry is reduced, and the probability of the occurrence of defects such as coating scribing and the like is reduced. Wherein the width direction is a direction shown in fig. 2.

In one embodiment, the first chamfer 132 and the second chamfer 332 are both rounded, and the radius of the rounded corner of the first chamfer 132 is the same as the radius of the rounded corner of the second chamfer 332.

In this specific example, the first chamfer 132 and the second chamfer 332 are provided as chamfers with the same shape, for example, the first chamfer 132 and the second chamfer 332 are both rounded, which is not only more beneficial to help the coating slurry smoothly transition to the substrate 4, but also simple in processing and easy to manufacture. Further, the first chamfer 132 and the second chamfer 332 are consistent in size, for example, in the case that both the first chamfer 132 and the second chamfer 332 are rounded, the radius of the first chamfer 132 and the radius of the second chamfer 332 are both R, and R is 0.5mm or more and 2.5mm or less. In other embodiments, the first chamfer 132 and the second chamfer 332 may both be provided at the same chamfer angle, which may also serve to help smooth the transition of the coating slurry onto the substrate 4.

Referring to fig. 3, in one embodiment, the die body comprises a first die block 1 and a second die block 3, the first die block 1 having a first surface 11, the second die block 3 having a second surface 31, the slot 101 being formed between the first surface 11 and the second surface 31; further, referring to fig. 1 and 2, the first module 1 has a third surface 131 intersecting the first surface 11 at the outlet 1011, the second module 3 has a fourth surface 331 intersecting the second surface 31 at the outlet 1011, and the third surface 131 is flush with the fourth surface 331; the first chamfer 132 is formed between the first surface 11 and the third surface 131; the second chamfer 332 is formed between the second surface 31 and the fourth surface 331.

In this particular example, the die body comprises in particular a two-part structure, namely a first block 1 and a second block 3, the first block 1 being arranged opposite the second block 3 with a slit 101 formed therebetween. Thus, the die body is easy to manufacture and install, and the slit 101 is formed in a simple manner. More specifically, the slit 101 is formed between the first surface 11 of the first module 1 and the second surface 31 of the second module 3, that is, the inner wall of the slit 101 includes the first surface 11 and the second surface 31, and the arrangement of the above-mentioned surfaces is not only convenient for installation, but also the slit 101 is formed in a simpler manner, and the size of the slit 101 is easier to control. Specifically, the first module 1 is provided with a first die lip 13 protruding from the outlet, the third surface 131 is the surface of the first die lip 13 facing the substrate 4, and the third surface 131 is connected with the first surface 11; the second die block 3 is provided with a second die lip 33 protruding from the outlet, the fourth surface 331 is the surface of the second die lip 33 facing the substrate 4, and the fourth surface 331 is connected with the second surface 31. The third surface 131 and the fourth surface 331 are located on the same plane, and the plane is parallel to the direction of the base material 4, so that the distances between the first die lip 13 and the base material 4 and the distances between the second die lip 33 and the base material 4 are always consistent, and the stability of the coating process is facilitated. Further, the thickness range of the first die lip 13 is 1.5mm to 5mm, and the thickness range of the second die lip 33 is 4.5mm to 15mm, so that the arrangement is favorable for enabling the first die lip 13 to be easily deformed by other mechanical devices in actual production, and therefore the width of the outlet of the slit 101 is conveniently adjusted, and the spraying amount of a local area is adjusted. Further specifically, a first chamfer 132 is provided between the first surface 11 and the third surface 131, and a second chamfer 332 is provided between the second surface 31 and the fourth surface 331. The first chamfer 132 and the second chamfer 332 can help smooth transition of the coating slurry onto the substrate 4, reduce the residence time of the coating slurry at the outlet end, significantly improve the flowing dead zone of the coating slurry at the outlet end, reduce the occurrence of coating slurry agglomeration and sedimentation, reduce the risk of forming large particles by the agglomeration and sedimentation of the coating slurry, and reduce the probability of occurrence of defects such as coating scribing.

Referring to fig. 1 and 3, a material storage cavity is further arranged in the die head body, and the material storage cavity is communicated with an inlet of the slit 101. In a specific example, a first material storage cavity 12 is formed in the first module 1, and the cross section of the first material storage cavity 12 can be circular or oval; a second material storage cavity 32 is formed in the second module 3, the cross section of the second material storage cavity 32 can also be circular or oval, and the first material storage cavity 12 is butted with the second material storage cavity 32 to form a material storage space inside the die head body together. Further, a feeding channel 34 is further disposed in the second module 3, and the feeding channel 34 is communicated with the second storage cavity 32. In the coating process of the pole piece, the coating slurry enters the storage space (the first storage chamber 12 and the second storage chamber 32) inside the die head body through the feed channel 34, and is sprayed on the substrate 4 through the slit 101. Besides the embodiments shown in fig. 1 and 3, a chamber, that is, a material storage chamber, may be provided only in the first module 1 or the second module 3.

Referring to fig. 1-2, in one embodiment, further, the first surface 11 is disposed obliquely to the third surface 131, the second surface 31 is disposed obliquely to the fourth surface 331, and the first surface 11 is parallel to the second surface 31.

In this specific example, the flow direction of the coating slurry in the slit 101 exhibits an inclined angle rather than a perpendicular angle with respect to the running direction of the base material 4, which causes the flow of the coating slurry to have a velocity component in accordance with the running direction of the base material 4 when the coating slurry flows out through the slit 101, thereby facilitating smooth coating of the coating slurry on the base material 4. Referring to fig. 1-3, further specifically, the first surface 11 and the second surface 31 are parallel to each other. The arrangement of the first surface 11 and the second surface 31 in parallel with each other makes the size of the slit 101 uniform, which facilitates the smooth flow of the coating slurry.

In one embodiment, further, the angle at which the first surface 11 is inclined with respect to the third surface 131 and the angle at which the second surface 31 is inclined with respect to the fourth surface 331 are both Q, and 50 ≦ Q ≦ 70.

The inclination angle within the above-mentioned size range is more advantageous in ensuring smooth application of the coating slurry to the base material 4.

Referring to fig. 3, in an embodiment, the die body further includes a shim 2, the shim 2 is sandwiched between the first die block 1 and the second die block 3, the shim 2 has a fifth surface 21 and a sixth surface 22 opposite to each other, the first surface 11 is attached to the fifth surface 21, the second surface 31 is attached to the sixth surface 22, a notch recessed in a direction away from the outlet is formed in the shim 2, the notch penetrates through the fifth surface 21 and the sixth surface 22, and the first surface 11 and the second surface 31 respectively cover the notch to form the slit 101.

In this particular example, the die body further includes a shim 2 sandwiched between the first die block 1 and the second die block 3. The first module 1 and the second module 3 are partially connected with the gasket 2, and the slits 101 are formed in the overlapping areas of the first module 1 and the second module 3 and the notches of the gasket 2. Thus, the slit 101 is formed in a simple manner, and the size of the slit 101 can be easily controlled. And the area between the first module 1 and the second module 3 outside the slit 101 is sealed by the gasket 2, so that the coating slurry is prevented from leaking at the position where discharging is not needed. More specifically, the first surface 11 of the first module 1 is attached to the fifth surface 21 of the gasket 2, the second surface 31 of the second module 3 is attached to the sixth surface 22 of the gasket 2, and both the first module 1 and the second module 3 are tightly connected to the gasket 2.

Referring to fig. 4 and 5, in an embodiment, further, the gasket 2 further has a seventh surface 23 connected between the fifth surface 21 and the sixth surface 22, the seventh surface 23 is respectively abutted against the third surface 131 and the fourth surface 331, and the seventh surface 23 is flush with the third surface 131 and the fourth surface 331.

In this particular example, the seventh surface 23 abuts and is coplanar with the third surface 131 and the fourth surface 331 on both sides of the die body, respectively, such that the seventh surface 23 closes off both sides of the die body at the outlet, which prevents the coating slurry from leaking out of both sides of the die body during the coating process.

Referring to fig. 4 and 5, in an embodiment, further, a third chamfer 24 is disposed between the seventh surface 23 and the fifth surface 21, and the third chamfer 24 is the same as the first chamfer 132; a fourth chamfer 25 is provided between the seventh surface 23 and the sixth surface 22, the fourth chamfer 25 being identical to the second chamfer 332.

Specifically, the third chamfer 24 and the first chamfer 132 are identical in shape and size and are completely coupled, and the fourth chamfer 25 and the second chamfer 332 are identical in shape and size and are completely coupled, so that the two sides of the die head body can be tightly closed, and the coating slurry can be further prevented from leaking out of the two sides of the die head body in the coating process.

Referring to fig. 3 and 4, in an embodiment, the gasket 2 further includes a main body portion 201 and two extending portions 202 connected to the main body portion 201, where the two extending portions 202 are disposed on the same side of the main body portion 201 at intervals; the fifth surface 21 and the sixth surface 22 both extend from the main body portion 201 to the extension portion 202; the area between the two extensions 202 is the recess 203 of the gasket 2.

In this specific example, the gasket 2 is similar to a "C-shaped" structure, the main body 201 and the two extending portions 202 of the gasket 2 are closely attached to the first surface 11 and the second surface 31, and the recess 203 between the two extending portions 202 forms the slit 101 in the area corresponding to the first surface 11 and the second surface 31. Alternatively, the main body portion 201 and the two extending portions 202 of the gasket 2 are integrally formed, so that the gasket 2 is simple in forming mode and easy to process and manufacture.

According to another embodiment of the present application, there is provided a coating apparatus comprising a coating die as described above. The coating device is used in the production process of the pole piece of the lithium battery.

In the above embodiments, the differences between the embodiments are described in emphasis, and different optimization features between the embodiments can be combined to form a better embodiment as long as the differences are not contradictory, and further description is omitted here in consideration of brevity of the text.

Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present application. The scope of the application is defined by the appended claims.

Claims

1. A coating die, comprising:

a die body in which a slit (101) for flowing a coating slurry is provided, the slit (101) having an outlet (1011) for flowing out the coating slurry; the outlet (1011) of the slit (101) is provided with a first chamfer (132) and a second chamfer (332) which are identical on two opposite inner walls in the width direction.

2. The coating die according to claim 1, wherein the first chamfer (132) and the second chamfer (332) are both rounded corners, and the radius of the rounded corner of the first chamfer (132) is the same as the radius of the rounded corner of the second chamfer (332).

3. The coating die according to claim 2, wherein the radius of the fillet of the first chamfer (132) and the radius of the fillet of the second chamfer (332) are both R, and 0.5mm ≦ R ≦ 2.5 mm.

4. The coating die according to claim 1, characterized in that said die body comprises a first die block (1) and a second die block (3), said first die block (1) having a first surface (11), said second die block (3) having a second surface (31), said slit (101) being formed between said first surface (11) and said second surface (31);

the first module (1) having a third surface (131) intersecting the first surface (11) at the outlet, the second module (3) having a fourth surface (331) intersecting the second surface (31) at the outlet, the third surface (131) being disposed flush with the fourth surface (331); the first chamfer (132) is formed between the first surface (11) and the third surface (131); the second chamfer (332) is formed between the second surface (31) and the fourth surface (331).

5. Coating die according to claim 4, characterized in that said first surface (11) is arranged obliquely with respect to said third surface (131) and said second surface (31) is arranged obliquely with respect to said fourth surface (331), said first surface (11) being parallel to said second surface (31).

6. The coating die according to claim 4, characterized in that the angle of inclination of the first surface (11) with respect to the third surface (131) and the angle of inclination of the second surface (31) with respect to the fourth surface (331) are both Q, and 50 ° ≦ Q ≦ 70 °.

7. The coating die according to claim 4, wherein the die body further comprises a shim (2), the shim (2) is sandwiched between the first die block (1) and the second die block (3), the shim (2) has a fifth surface (21) and a sixth surface (22) which are oppositely arranged, the first surface (11) is attached to the fifth surface (21), the second surface (31) is attached to the sixth surface (22), the shim (2) is provided with a notch which is recessed in a direction away from the outlet, the notch penetrates through the fifth surface (21) and the sixth surface (22), and the first surface (11) and the second surface (31) respectively cover the notch to form the slit (101).

8. The coating die according to claim 7, characterized in that said shim (2) further has a seventh surface (23) connected between said fifth surface (21) and a sixth surface (22), said seventh surface (23) being in abutment with said third surface (131) and said fourth surface (331), respectively, and said seventh surface (23) being arranged flush with said third surface (131) and said fourth surface (331).

9. The coating die according to claim 8, characterized in that a third chamfer (24) is provided between said seventh surface (23) and said fifth surface (21), said third chamfer (24) being identical to said first chamfer (132); a fourth chamfer (25) is provided between the seventh surface (23) and the sixth surface (22), the fourth chamfer (25) being identical to the second chamfer (332).

10. A coating apparatus comprising a coating die according to any one of claims 1 to 9.