CN109939884A - Non-full coverage diaphragm coating device and diaphragm coating process - Google Patents

Abstract

The invention provides a non-full coverage diaphragm coating device and a diaphragm coating process, relates to the technical field of lithium battery processing, and solves the technical problems of complex structure and high cost of the non-full coverage diaphragm coating device in the prior art . The non-full-coverage diaphragm coating device includes a micro gravure roll and a silo, wherein the silo is arranged on one side of the micro gravure roll, and the silo is provided with a silo outlet, and the slurry in the silo can flow directly into the micro gravure through the silo outlet. Inside the groove hole structure on the circumferential surface of the gravure roll. The present invention is used for the coating of battery separators.

Description

Non-full coverage diaphragm coating device and diaphragm coating process

technical field

The invention relates to the technical field of lithium battery processing, in particular to a non-full coverage diaphragm coating device and a diaphragm coating process.

Background technique

In order to improve the safety of lithium batteries, most of the existing technologies use inorganic nanoparticles with stable properties to coat polypropylene or polyethylene microporous films to improve the thermal stability of the microporous films, and coat full-coverage polymer adhesives. The junction layer improves the heat resistance of the separator and the adhesion between the separator and the lithium battery pole piece. However, after the polymer and the electrolyte form a gel layer, the conductivity of the electrolyte drops to 10%, which is not conducive to the conduction of lithium ions, increases the internal resistance of the lithium battery, and affects the rate discharge and cycle performance of the lithium battery. Lithium batteries not only require good thermal stability and adhesion between the separator and electrodes, but also require fast charging performance. Therefore, there is a method of non-full-coverage coating of the adhesive layer, and the area without polymer glue dots can realize lithium The effective transport of ions improves the lithium ion conductivity of the separator, thereby improving the charge and discharge performance of the lithium battery.

The applicant found that the prior art has at least the following technical problems:

The existing non-full coverage diaphragm coating device has complex structure and large investment, and it is difficult to combine with the existing production line.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a non-full-coverage diaphragm coating device and a diaphragm coating process, and solve the technical problems of complex structure and high cost of the non-full-coverage diaphragm coating device in the prior art. The technical effects that can be produced by the preferred technical solutions among the technical solutions provided by the present invention are detailed in the following descriptions.

For achieving the above object, the invention provides the following technical solutions:

A non-full-coverage diaphragm coating device provided by the present invention includes a micro gravure roll and a silo, wherein the silo is arranged on one side of the micro gravure roll, and the silo is provided with a silo outlet. The slurry in the silo can flow directly into the groove hole structure on the circumferential surface of the microgravure roll through the silo outlet.

Preferably, the non-full coverage membrane coating device further comprises a scraping device, and the scraping device is used to remove the slurry on the surface of the micro gravure roll.

Preferably, the scraping device includes a scraper for removing the slurry on the surface of the microgravure roll.

Preferably, the silo is a scraping hopper, and the part of the scraping hopper in contact with the micro gravure roll forms the scraping device.

Preferably, the groove hole structure includes a large groove hole structure and a small groove hole structure, and the large groove hole structure and the small groove hole structure are evenly spaced along the axial direction of the micro gravure roll and distributed along the axis of the micro gravure roll. The circumferential direction of the microgravure roll is evenly spaced apart.

Preferably, on the same cross section, the diameter of the large groove hole structure is larger than the diameter of the small groove hole structure, and the depth of the large groove hole structure is greater than or less than or equal to the small groove hole structure. Depth; or, on the same cross section, the diameter of the large groove hole structure is equal to the diameter of the small groove hole structure, and the depth of the large groove hole structure is greater than or equal to the depth of the small groove hole structure .

Preferably, the micro gravure roll is provided with an axial connecting line groove, and the axial connecting line groove passes through the center of all the groove hole structures in the same row along the axis direction of the micro gravure roll; and/or all The micro-gravure roller is provided with a circumferential connecting line groove, and the circumferential connecting line groove passes through the center of all the groove hole structures in the same circle along the circumferential direction of the micro-gravure roller; and/or the micro-gravure plate The roller is provided with a spiral connecting wire groove, and the spiral connecting wire groove is in a spiral shape and passes through the center of all the groove hole structures in the same row.

Preferably, the diameter of the micro gravure roll ranges from 30 mm to 500 mm; the depth of the groove hole structure on the surface of the micro gravure roll ranges from 10 μm to 220 μm; the diameter of the micro gravure roll groove structure ranges from 30 μm to 500 μm. .

Preferably, the groove hole structures of each row along the axis direction of the micro gravure roll are distributed in a spiral shape.

A diaphragm coating process for coating a battery diaphragm by a non-full coverage diaphragm coating device, comprising the following contents: the micro gravure roll rotates and the slurry in the silo flows into the circumferential surface of the micro gravure roll In the groove hole structure on the upper;

A scraping device scrapes off excess slurry on the circumferential surface of the microgravure roll;

The slurry of the grooved hole structure is coated on the diaphragm which is close to the microgravure roll and moves.

In the non-full-coverage diaphragm coating device provided by the invention, the silo is directly matched with the micro gravure roll, and the slurry flowing out from the silo outlet of the silo can directly flow into the groove structure on the micro gravure roll, and the structure is simple and versatile. It is strong and easy to operate, thereby solving the technical problems of complex structure and high cost of the non-full coverage diaphragm coating device in the prior art.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that are used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative efforts.

1 is a schematic structural diagram of a non-full coverage diaphragm coating device provided by an embodiment of the present invention;

2 is a schematic front view of a microgravure roll provided by an embodiment of the present invention (the diameters of the same cross-section of the large groove hole structure and the small groove hole structure are different);

3 is another schematic front view of the micro gravure roll provided by the embodiment of the present invention (the diameters of the same cross section of the large groove hole structure and the small groove hole structure are different, and the groove hole structure is a helical line along the axis direction of the micro gravure roll shape);

4 is another schematic front view of a microgravure roll provided by an embodiment of the present invention (the diameter of the same cross-section of the large groove hole structure and the small groove hole structure is the same);

5 is another schematic front view of the micro gravure roll provided by the embodiment of the present invention (the large groove hole structure and the small groove hole structure have the same diameter of the same cross section, and the groove hole structure is spiral along the axis direction of the micro gravure roll. linear);

6 is a schematic structural diagram of an axially connecting wire groove and a circumferentially connecting wire groove on a microgravure roller provided by an embodiment of the present invention;

Fig. 7 is the structural schematic diagram of the circumferential connection groove of the micro gravure roller provided by the embodiment of the present invention (the groove hole structure is helical along the axis direction of the micro gravure roller);

FIG. 8 is a schematic structural diagram of an axial connecting wire groove, a circumferential connecting wire groove and a spiral connecting wire groove on a microgravure roller provided by an embodiment of the present invention.

In the figure, 1- micro gravure roller; 2- silo; 21- silo outlet; 3- groove hole structure; 31- small groove hole structure; 32- large groove hole structure; 4- scraper; 5- diaphragm; 6-Axial connection slot; 7-Circumferential connection slot; 8-Spiral connection slot.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

1-8, the present invention provides a non-full coverage diaphragm coating device, including a micro gravure roll 1 and a silo 2, wherein the silo 2 is arranged on one side of the micro gravure roll 1, and the silo 2 A silo outlet 21 is provided, and the slurry in the silo 2 can directly flow into the groove hole structure 3 on the circumferential surface of the microgravure roll 1 through the silo outlet 21 . In the prior art, the silo 2 is not directly matched with the micro gravure roll 1, and the slurry in the silo 2 is transferred to the micro gravure roll 1 by a structure such as a material transfer roll, which is complicated in structure and high in cost; The non-full coverage diaphragm coating device, the silo 2 is directly matched with the micro gravure roll 1, the slurry flowing out from the silo outlet 21 of the silo 2 can directly flow into the groove structure 3 on the micro gravure roll 1, and the structure is simple, And it is easy to combine with the production line, with strong versatility and convenient operation. In addition, the microgravure roll 1 can be a roll with ceramic material sprayed on the surface, which is consistent with the existing technical system and is convenient for implementation.

As an optional implementation of the embodiment of the present invention, the non-full coverage diaphragm coating device further includes a scraping device, and the scraping device is used to remove the slurry on the surface of the micro gravure roll 1 . Referring to FIG. 1, the scraping device includes a scraper 4, and the scraper 4 can remove excess slurry on the surface of the microgravure roll 1; The contact part of the roll 1 forms a scraping device, and a scraping hopper is used to remove the excess slurry on the surface of the microgravure roll 1 .

As an optional implementation of the embodiment of the present invention, the groove hole structure 3 includes a large groove hole structure 32 and a small groove hole structure 31, and the large groove hole structure 32 and the small groove hole structure 31 are along the The distribution is uniformly spaced in the axial direction and uniformly spaced in the circumferential direction of the microgravure roll 1 . The large groove hole structure 32 and the small groove hole structure 31 are evenly distributed on the micro gravure roll 1, so that the slurry can be uniformly coated on the separator, and the performance of the separator can be improved.

As an optional implementation of the embodiment of the present invention, in order to achieve a variety of uniform coating methods for the diaphragm, the following methods can be used. For example, the diameter of the large groove hole structure 32 is larger than the diameter of the small groove hole structure 31 on the same cross section diameter, the depth of the large groove hole structure 32 is greater than or less than or equal to the depth of the small groove hole structure 31, see FIG. 2, the large groove hole structure 32 and the small groove hole structure 31 are evenly spaced; alternatively, see FIG. 4 , the diameter of the large groove hole structure 32 is equal to the diameter of the small groove hole structure 31 on the same cross section, and the depth of the large groove hole structure 32 is greater than the depth of the small groove hole structure 31; The diameter of the groove hole structure 32 is equal to the diameter of the small groove hole structure 31 , and the depth of the large groove hole structure 32 is equal to the depth of the small groove hole structure 31 , that is, the difference between the small groove hole structure 31 and the large groove hole structure 32 . Same structure.

As an optional implementation of the embodiment of the present invention, the micro gravure roll 1 is provided with an axial connecting line groove 6, and the axial connecting line groove 6 passes through the center of all the groove hole structures 3 in the same row along the axis direction of the micro gravure roll 1 , and/or the micro gravure roller 1 is provided with a circumferential connection groove 7, and the circumferential connection groove 7 passes through the center of all groove hole structures 3 in the same circle along the circumferential direction of the micro gravure roller 1; and/or the micro gravure The roller 1 is provided with a spiral connecting wire groove 8, and the spiral connecting wire groove 8 is helical and passes through the center of all the groove hole structures 3 in the same row. Referring to Fig. 6, Fig. 6 shows the axial connection slot 6 and the circumferential connection slot 7; Fig. 7 illustrates the circumferential connection slot 7; Fig. 8 illustrates the axial connection slot 6, the circumferential connection slot 7 Connection slot 7 and spiral connection slot 8. The depth of the axial connecting wire groove 6 , the circumferential connecting wire groove 7 and the spiral connecting wire groove 8 is smaller than that of the groove hole structure 3 .

As an optional implementation of the embodiment of the present invention, the diameter of the micro gravure roll 1 ranges from 30 mm to 500 mm; the depth range of the groove hole structure 3 on the surface of the micro gravure roll 1 is 10 μm to 220 μm; the groove hole structure 3 of the micro gravure roll 1 The diameter range of 30μm ~ 500μm.

As an optional implementation of the embodiment of the present invention, the groove hole structures 3 in each row along the axis direction of the microgravure roll 1 are distributed in a spiral shape. Referring to Figure 3, Figure 5 and Figure 7, the groove hole structure 3 is evenly distributed along the micro gravure roll 1, and the micro gravure roll 1 with this structure is used to coat the diaphragm type, and the connecting line of the slurry along the width direction of the diaphragm is not. The connecting line is perpendicular to the length direction of the diaphragm, but has an inclined angle with respect to the width direction of the diaphragm, for example, it can be inclined by 1°.

A diaphragm coating process for coating a battery diaphragm by a non-full-covering diaphragm coating device, comprising the following contents: a micro gravure roll 1 rotates and the slurry in a silo 2 flows into a groove hole structure on the circumferential surface of the micro gravure roll 1 3; during the rotation of the micro gravure roll 1, the scraper 4 scrapes off the excess slurry on the circumferential surface of the micro gravure roll 1; the diaphragm is tightly attached to the micro gravure roll 1, so that the slurry of the groove hole structure Spread on the moving diaphragm to form a uniform non-full coverage coating. The coated separator is baked in an oven to form a stable coated separator.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. a kind of non-all standing diaphragm apparatus for coating, which is characterized in that including dimple roller (1) and feed bin (2), wherein

Feed bin (2) setting is provided with bin outlet (21), institute on the side of the dimple roller (1), the feed bin (2) State the slurry in feed bin (2) can be flowed directly by the bin outlet (21) it is recessed in dimple roller (1) peripheral surface In slotted hole structure (3).

2. non-all standing diaphragm apparatus for coating according to claim 1, which is characterized in that the non-all standing diaphragm coating Device further includes scraper, and the scraper is to remove the slurry on dimple roller (1) surface.

3. non-all standing diaphragm apparatus for coating according to claim 2, which is characterized in that the scraper include to Remove the scraper (4) of dimple roller (1) surface size.

4. non-all standing diaphragm apparatus for coating according to claim 2, which is characterized in that the feed bin (2) is to scrape hopper, It is described to scrape the part that hopper is in contact with the dimple roller (1) and form the scraper.

5. non-all standing diaphragm apparatus for coating according to claim 1, which is characterized in that groove pore structure (3) packet Include big groove pore structure (32) and little groove pore structure (31), the big groove pore structure (32) and little groove pore structure (31) edge The axis direction of the dimple roller (1) be evenly spaced on and along the dimple roller (1) circumferential direction uniform intervals Distribution.

6. non-all standing diaphragm apparatus for coating according to claim 5, which is characterized in that described big on same cross section The diameter of groove pore structure (32) is greater than the diameter of the little groove pore structure (31), the depth of the big groove pore structure (32) It is more than or less than or is equal to the depth of the little groove pore structure (31)；Alternatively, the big groove hole knot on same cross section The diameter of structure (32) is equal to the diameter of the little groove pore structure (31), and the depth of the big groove pore structure (32) is greater than or waits In or be less than the little groove pore structure (31) depth.

7. non-all standing diaphragm apparatus for coating according to claim 5, which is characterized in that set on the dimple roller (1) It is equipped with axial connection wire casing (6), axial connection wire casing (6) passes through the same row along dimple roller (1) axis direction All groove pore structure (3) centers；

And/or circumferential connection wire casing (7) is provided on the dimple roller (1), circumferential connection wire casing (7) passes through along described Same all groove pore structure (3) centers of circle in dimple roller (1) circumferential direction；

And/or spiral connection wire casing (8) is provided on the dimple roller (1), spiral connection wire casing (8) is helically linear And pass through all groove pore structure (3) centers of same row.

8. non-all standing diaphragm apparatus for coating described according to claim 1 or 5 or 6 or 7, which is characterized in that the dimple version The diameter range of roller (1) is 30mm~500mm；The depth bounds of dimple roller (1) the surface groove pore structure (3) are 10 μm ~220 μm；The diameter range of dimple roller (1) the groove pore structure (3) is 30 μm~500 μm.

9. non-all standing diaphragm apparatus for coating described according to claim 1 or 5 or 6 or 7, which is characterized in that each row is along institute The groove pore structure (3) stated on dimple roller (1) axis direction is spirally distributed.

10. it is a kind of using the described non-all standing diaphragm apparatus for coating coating battery diaphragm of any of claims 1-9 every Film coating process, which is characterized in that including the following contents,

Slurry in dimple roller (1) rotation and the feed bin (2) flows into recessed in dimple roller (1) peripheral surface In slotted hole structure (3)；

Scraper wipes slurry extra in dimple roller (1) peripheral surface off；

The slurry of the groove pore structure (3), which is coated on, is adjacent to the dimple roller (1) and on mobile diaphragm (5).