CN217646809U

CN217646809U - Pole piece coating auxiliary assembly, pole piece coating device and pole piece processing system

Info

Publication number: CN217646809U
Application number: CN202221247848.0U
Authority: CN
Inventors: 郑永光; 徐亚杰; 王茂范
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2022-05-23
Filing date: 2022-05-23
Publication date: 2022-10-25
Anticipated expiration: 2032-05-23

Abstract

The utility model provides a pole piece coating auxiliary assembly, a pole piece coating device and a pole piece processing system, wherein the pole piece coating auxiliary assembly comprises a roller body with a plurality of thermal stripping adhesive tapes and a plurality of compression rollers; the roller body can be driven to rotate to unreel each thermal peeling adhesive tape, and the thermal peeling adhesive tapes can be adhered to the blank area and at least cover one side of the blank area, which is adjacent to the coating area on the pole piece; the compression roller is used for compressing the hot peeling adhesive tape to the surface of the blank area; the coated area and the thermal release tape can be coated simultaneously, and the thermal release tape can be peeled from the margin area by being heated. Pole piece coating auxiliary assembly unreels the hot peeling off sticky tape through the roll body to and the compression roller compresses tightly the hot peeling off sticky tape in the one side of leaving the adjacent coating district in white district, make hot peeling off sticky tape and coating district coated together, peel off by heating through hot peeling off sticky tape, then can prevent that the edge in coating district from appearing cutting thin the district, and then do benefit to the security that improves the pole piece.

Description

Pole piece coating auxiliary assembly, pole piece coating device and pole piece processing system

Technical Field

The utility model relates to a pole piece processing equipment technical field, in particular to pole piece coating auxiliary assembly. And simultaneously, the utility model discloses still relate to a pole piece coating unit who is equipped with this kind of pole piece coating auxiliary assembly to and be equipped with this pole piece coating unit's pole piece system of processing.

Background

However, as the application of lithium ion batteries is popularized, people pay more and more attention to the safety of the batteries. In the use process of the lithium battery, the problems of N/P ratio design, electrode material inactivation, poor pole piece adhesion and the like easily cause the phenomenon that lithium metal is precipitated on the surface of a negative electrode. Along with the growth of lithium dendrite, there is the risk that impales the diaphragm and switches on positive negative pole and lead to inside short circuit, simultaneously because the characteristics of lithium cell high energy density, inside short circuit leads to the battery to appear thermal runaway inefficacy easily, and serious can cause safety risks such as fire, explosion even.

Due to the flow characteristics of the positive and negative electrode slurry in the coating process of the pole piece, the edge of the coating area after coating has a thickness lower than that of the coating area, the edge area of the pole piece with the thinner thickness is called as a thinning area, and the thinning area is positioned on the blank area of the pole piece without coating the slurry. The existence of the thinning area in the pole piece coating process is a common main factor causing the lithium metal precipitation phenomenon.

The control method of the thinning area of the current common lithium ion battery mainly comprises the following steps:

1. the viscosity of the slurry is increased to reduce the flowing characteristic of the slurry, but the increase of the viscosity of the slurry easily causes the problems of uneven pole piece coating, nozzle blockage by the slurry, slurry caking and wave material on the edge part of the rolled pole piece.

2. The addition of the spacer at the edge of the coating controls the slurry flow, but the addition of the spacer also easily causes the slurry at the edge to generate vortex at the contact part of the slurry and the spacer during the coating process, thereby generating abnormal conditions such as edge V-angle.

3. The slurry flow is controlled by adjusting the coating speed and the coating pressure, but the improvement effect of the method is not obvious, and the normal production is influenced to cause the production stoppage.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model aims at providing a pole piece coating auxiliary assembly to reduce the thin problem in edge appears in the coating district on the pole piece, and then improve the security of pole piece.

In order to achieve the above purpose, the technical scheme of the utility model is realized as follows:

a pole piece coating auxiliary assembly is used for assisting the forming of a blank area on a pole piece, and comprises a roller body with a plurality of thermal stripping adhesive tapes and a plurality of compression rollers;

the roller body can be driven to rotate to unreel each thermal peeling adhesive tape, and the thermal peeling adhesive tapes can be adhered to the blank regions and at least cover one side of the blank regions, which is adjacent to the coating regions on the pole pieces;

the press roller is used for pressing the hot peeling adhesive tape to the surface of the white space.

The coated area and the thermal release tape can be coated simultaneously, and the thermal release tape can be peeled from the margin area by being heated.

Further, an annular bulge which corresponds to the thermal peeling adhesive tape is arranged on the outer peripheral wall of the compression roller; the thickness of the annular bulge is 0.5-5 cm.

Further, the width of the thermal peeling adhesive tape is 1 mm-30 mm.

Further, the thickness of the thermal peeling adhesive tape is 5 um-200 um.

Further, the width of the thermal peeling adhesive tape does not exceed the width of the margin area; the width of the white region is 1 mm-50 mm; the width of the coating area is 5-300cm.

Compared with the prior art, the utility model discloses following advantage has:

pole piece coating auxiliary assembly unreels the hot peeling tape through the roll body to and the compression roller compresses tightly the hot peeling tape in the one side that the neighbouring coating district in leaving white district set up, can make hot peeling tape can be scribbled with the coating district together, and peel off on the district because of being heated by leaving white through hot peeling tape, then can prevent that the edge in coating district from appearing cutting thin the district, and then do benefit to the security that improves the pole piece.

In addition, the arrangement of the annular bulges is beneficial to improving the compression effect of the compression roller on the thermal peeling adhesive tape, so that the stability of the thermal peeling adhesive tape in use can be improved. The arrangement of the width range of the thermal peeling tape can ensure that the thinned area can be covered, thereby being beneficial to preventing the thinned area. The thickness range of the thermal peeling adhesive tape can meet the use requirement of the thermal peeling adhesive tape in coating. The arrangement of the width range of the blank area is suitable for the pole pieces with most specifications.

Additionally, another aim at of the utility model is to provide a pole piece coating device, including the unreeling roller that is used for unreeling the pole piece, be used for the rolling the wind-up roll of pole piece to and the coating die head, pole piece coating device still includes as above pole piece coating auxiliary assembly, the roll body is located the upper reaches of coating die head, just the coating die head can be synchronous right the coating district of pole piece with the hot stripping adhesive tape coats.

Pole piece coating unit, through setting up as above pole piece coating auxiliary assembly, do benefit to the coating die head and carry out the coating to coating district and hot stripping adhesive tape simultaneously, and then do benefit to the coating uniformity that improves coating district on the pole piece, and can improve the security of pole piece.

And simultaneously, another aim at of the utility model provides a pole piece system of processing, including the stoving case, still include as above pole piece coating device, unreel the roller with the roll body is located the upper reaches of stoving case entry, the wind-up roll is located the low reaches of stoving case export, just the hot stripping sticky tape can in the stoving incasement by peel off on the white district, the heating temperature scope of stoving incasement is 50 ~ 150 ℃.

Furthermore, a plurality of blowing heads are arranged in the drying box, the blowing heads are used for blowing air to the pole pieces, and the speed of blowing air by the blowing heads is greater than 0.2m/s.

Further, the pole piece processing system also comprises a recovery unit arranged in the drying box, and the recovery unit is provided with an adhesive layer; the adhesive layer is capable of adhering the thermal release tape peeled off by the margin.

Furthermore, the recovery unit is a collection box arranged below the pole piece, and the bonding layer is arranged on the inner wall of the collection box.

Pole piece system of processing, through setting up as above pole piece coating unit, can realize the coating and the stoving of pole piece, simultaneously, the hot stripping adhesive tape can also break away from by leaving white district because of being heated at the stoving incasement, does benefit to the thin district of cutting at elimination coating district edge to can obtain the pole piece that coating thickness uniformity is good.

Drawings

The accompanying drawings, which form a part of the present disclosure, are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and together with the description serve to explain the present disclosure. In the drawings:

fig. 1 is a schematic structural view of a pole piece coating auxiliary assembly according to a first embodiment of the present invention;

fig. 2 is a schematic structural view of a pole piece coating apparatus according to a first embodiment of the present invention;

fig. 3 is a schematic structural diagram of a pole piece processing system according to the second embodiment of the present invention;

fig. 4 is a schematic structural view of the inside of a drying box according to the second embodiment of the present invention;

description of reference numerals:

1. pole pieces; 2. thermally stripping the adhesive tape; 3. a compression roller; 4. a roller body; 5. a coating die head; 6. a drying box;

101. a white region is left; 102. a coating area;

301. an annular projection;

601. an inlet of the drying box; 602. an outlet of the drying box; 603. a collection box; 604. an adhesive layer; 605. a blowing head;

a. width of the thermal release tape; b. the width of the white space; c. the width of the coating zone.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features of the embodiments of the present invention may be combined with each other.

In the description of the present invention, it should be noted that, if terms indicating orientation or positional relationship such as "upper", "lower", "inner", "back", etc. appear, they are based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the appearances of the terms first, second, etc. in this specification are not necessarily all referring to the same order, but are to be construed as referring to the same order.

The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Example one

The embodiment relates to a pole piece coating auxiliary assembly which is used for assisting the forming of a blank area 101 on a pole piece 1. On the whole, the pole piece coating auxiliary assembly comprises a roller body 4 with a plurality of thermal stripping adhesive tapes 2 and a plurality of pressing rollers 3. The roller 4 can be driven to rotate to unreel each thermal peeling tape 2, and the thermal peeling tape 2 can be adhered to the margin area 101 and at least cover one side of the margin area 101, which is adjacent to the coating area 102 on the pole piece 1. The press roller 3 is used to press the thermal release tape 2 to the surface of the margin area 101, the coating area 102 and the thermal release tape 2 can be coated at the same time, and the thermal release tape 2 can be peeled off from the margin area 101 by being heated.

Based on the above general description, an exemplary structure of the pole piece coating auxiliary assembly described in the present embodiment is shown in fig. 1, a pole piece 1 travels between an unwinding roller and a winding roller which are not shown in the figure, the pole piece 1 has blank areas 101 and coating areas 102 which are staggered in the width direction of the pole piece 1, wherein there are three blank areas 101 and two coating areas 102. The roller body 4 in this embodiment is disposed above the pole piece 1, three rolls of thermal release tapes 2 are wound thereon, and the thermal release tapes 2 in each roll are disposed corresponding to each blank area 101, so as to be bonded on the blank areas 101. It can be understood that the number of the margin areas 101 on the pole piece 1 can be increased or decreased according to the use requirement, and in this case, it is only required to ensure that the number of the thermal peeling tapes 2 is matched with the number of the margin areas 101.

The width b of the blank region in this embodiment is 1mm to 50mm, for example, the width b of the blank region is 1mm, 10mm, 20mm, 30mm, 40mm or 50mm. The setting of the width b of the blank area can meet the requirement of coating most of the pole pieces 1, so that the pole piece coating auxiliary assembly in the embodiment has better universality. Accordingly, the width c of each coated area is equal to the width of the pole piece 1 minus the width b of all the blank areas, divided by the number of coated areas 102. Preferably, the width c of the coating region in this embodiment is 5-300cm, for example, 5cm, 50cm, 100cm, 150cm, 200cm, 250cm, or 300cm. It should be noted that the roller 4 in this embodiment can be driven by a driving motor to rotate, so as to unwind the thermal peeling tape 2, and the unwinding speed of the thermal peeling tape 2 should be consistent with the traveling speed of the pole piece 1, so as to ensure that the thermal peeling tape 2 adhered on the margin area 101 can travel synchronously with the pole piece 1. In specific implementation, the free ends of the three thermal peeling tapes 2 are manually bonded to the corresponding margin regions 101, and then the thermal peeling tapes 2 can be automatically bonded to the margin regions 101 under the action of the roller body 4 and the pressing roller 3.

The thermal peeling tape 2 in this embodiment can be a mature product in the prior art, and the adhesive layer components of the thermal peeling tape 2 mainly include acrylic pressure-sensitive adhesive, low-temperature thermal expansion microspheres, etc. (two or more materials with different temperature expansion coefficients can play a role in conventional adhesion at normal temperature, and under the heating condition, the thermal peeling tape 2 can be deformed and bent due to shrinkage stress and lose adhesiveness at the same time because of different softening points of the materials with different expansion coefficients, so that the surface of the pole piece 1 falls off).

It may be deformed completely and lose its viscosity by being heated, and thus can be peeled off from the margin 101. In addition, in order to ensure the effect of eliminating the edge thinning region of the application region 102, the thermal peeling tape 2 in the present embodiment extends from the side of the application region 102 toward a direction away from the application region 102. So arranged, the thermal peeling tape 2 can be ensured to cover at least one side of the margin area 101 adjacent to the coating area 102 on the pole piece 1. Thus, the thermal peeling tape 2 and the coating region 102 can be coated simultaneously, and the slurry coated on the thermal peeling tape 2 can be dropped simultaneously by peeling the thermal peeling tape 2 from the margin region 101 while being heated, so that the thickness of the coating region 102 is uniform and the thinned regions are less likely to occur at both side edges thereof.

In a preferred embodiment, the number of the pressing rollers 3 is one, and all three unwound thermal release tapes 2 are pressed by the pressing rollers 3. In order to improve the use effect of the press roller 3, an annular protrusion 301 corresponding to the thermal peeling tape 2 is provided on the outer peripheral wall of the press roller 3, and the press roller 3 presses the thermal peeling tape 2 against the blank space 101 through the annular protrusion 301. In specific implementation, the thickness of the annular protrusion 301 is 0.5-5 cm. That is, the thickness of the portion of the annular protrusion 301 which is higher than the outer wall of the press roll 3 is 0.5 to 5cm, for example, 0.5cm, 1cm, 2cm, 3cm, 4cm, or 5cm.

The number of the pressing rollers 3 may be increased according to the use requirement, for example, three rolls of the thermal peeling tape 2 are wound around different pressing rollers 3, and the thermal peeling tape 2 can be pressed against the margin area 101.

In addition, the width a of the thermal peeling tape does not exceed the width b of the margin. In order to improve the effect of using the thermal peeling tape 2, the width a of the thermal peeling tape in this embodiment is 1mm to 30mm. For example, the width a of the thermal peeling tape is 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, or 30mm. When the width a of the thermal release tape is within this range, not only a good covering effect is obtained, but also peeling from the margin area 101 is facilitated. And the thickness of the thermal peeling tape 2 is 5um to 200um, for example, the thickness of the thermal peeling tape 2 is 5um, 50um, 100um, 150um or 200um. When the thermal peeling tape 2 is within the thickness range, the requirement of the coating thickness of the coating area 102 can be met, and the thermal peeling tape 2 is also favorably peeled from the margin area 101 in a heating environment. The thermal peeling tape 2 in this embodiment can be peeled from the margin portion 101 at a heating temperature of 50 ℃ or higher.

The pole piece coating auxiliary assembly described in this embodiment unreels thermal peeling adhesive tape 2 through roll body 4 to and compression roller 3 compresses thermal peeling adhesive tape 2 at the one side that the adjacent coating district 102 of margin district 101 set up, can make thermal peeling adhesive tape 2 can be coated with coating district 102 together, and peel off on the margin district 101 because of being heated through thermal peeling adhesive tape 2, then can prevent that the edge in coating district 102 from appearing thinning the district, and then do benefit to the security that improves pole piece 1.

In addition, this embodiment still relates to a pole piece coating unit, including being used for unreeling the unreeling roller of pole piece 1, the wind-up roll that is used for rolling pole piece 1 to and coating die 5. As shown in fig. 2, the pole piece coating apparatus in this embodiment further includes the above pole piece coating auxiliary assembly, the roller 4 is located upstream of the coating die 5, and the coating die 5 can simultaneously coat the coating region 102 of the pole piece 1 and the thermal release tape 2.

The pole piece coating device described in this embodiment, through setting up the pole piece coating auxiliary assembly as described above, is favorable to coating die head 5 to coat coating area 102 and thermal peeling tape 2 simultaneously, and then is favorable to improving the coating uniformity of coating area 102 on pole piece 1, and can improve the security of pole piece 1.

Example two

The embodiment relates to a pole piece processing system, which comprises a drying box 6 and further comprises a pole piece coating device, wherein an unwinding roller and a roller body 4 are positioned at the upstream of an inlet 601 of the drying box, a winding roller is positioned at the downstream of an outlet 602 of the drying box, and a thermal stripping adhesive tape 2 can be stripped from a blank area 101 in the drying box 6.

Wherein the heating temperature range in the drying box 6 is 50-150 ℃. For example, the temperature is 50 ℃, 100 ℃, or 150 ℃. So set up, do benefit to the stripping efficiency who improves hot glass sticky tape 2.

As shown in fig. 3 and fig. 4, a plurality of blowing heads 605 are arranged in the drying box 6, and the blowing heads 605 are used for blowing air to the pole pieces 1, so that the drying effect of the slurry is improved. The blowing head 605 blows a gas velocity greater than 0.2m/s. Namely, the blowing effect is better when the speed of the blowing gas is more than 0.2m/s.

The blowing head 605 in the preferred embodiment blows air obliquely downward, which is beneficial to improving the drying efficiency, and is beneficial to peeling the thermal peeling tape 2 from the margin area 101 and taking away the slurry coated on the margin area, so that the thermal peeling tape 2 is left in the drying box 6, and the thermal peeling tape 2 is taken out by opening the drying box 6 periodically. Of course, the blowing head 605 may also be disposed at other positions of the drying box 6, and the blowing direction is changed as long as the use requirement is satisfied.

In a preferred embodiment, the pole piece processing system further comprises a recycling unit disposed in the drying box 6, wherein the recycling unit has an adhesive layer 604, and the adhesive layer 604 can adhere the thermal release tape 2 peeled from the margin area 101, thereby facilitating recycling of the thermal release tape 2. As shown in FIG. 4, the recovery unit in this embodiment is a collection box 603 disposed below the pole piece 1, and an adhesive layer 604 is disposed on the inner wall of the collection box 603, and blows an air flow at a blowing head 605. Further, a plurality of protrusions protruding upward may be provided in the collection tank, and the plurality of protrusions are arranged in the collection tank 603 in a staggered manner. With this arrangement, the adhesive layer 604 can be adhered to the protrusions, which is advantageous for further improving the adhesion and recovery effect of the thermal release tape 2.

In addition, the slurry falling on the pole piece 1 can be blown away by the blowing of the blowing head 605, and simultaneously, the surface of the pole piece 1 can be cleaned by a hairbrush in the prior art before the pole piece 1 is wound, so that the coating effect of the pole piece 1 is further ensured.

The pole piece processing system of this embodiment, through setting up such as above pole piece coating unit, can realize the coating and the stoving of pole piece 1, simultaneously, hot peel off sticky tape 2 can also be in stoving case 6 because of being heated and break away from by leaving white district 101, does benefit to the thin district of eliminating coating district 102 edge to can obtain pole piece 1 that the coating thickness uniformity is good.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a pole piece coating auxiliary assembly for the shaping of leaving white district (101) on the auxiliary pole piece (1), its characterized in that:

the pole piece coating auxiliary assembly comprises a roller body (4) with a plurality of thermal stripping adhesive tapes (2) and a plurality of pressing rollers (3);

the roller body (4) can be driven to rotate to unreel each thermal peeling adhesive tape (2), and the thermal peeling adhesive tapes (2) can be adhered to the blank leaving area (101) and at least cover one side of the blank leaving area (101) which is adjacent to the coating area (102) on the pole piece (1);

the pressing roller (3) is used for pressing the hot peeling adhesive tape (2) to the surface of the white space (101);

the application region (102) and the thermal release tape (2) can be applied simultaneously, and the thermal release tape (2) can be peeled off from the margin region (101) by being heated.

2. The pole piece coating auxiliary assembly of claim 1, wherein:

the outer peripheral wall of the compression roller (3) is provided with an annular bulge (301) which corresponds to the thermal peeling adhesive tape (2);

the thickness of the annular bulge (301) is 0.5-5 cm.

3. The pole piece coating auxiliary assembly of claim 1, wherein:

the width (a) of the thermal peeling tape is 1 mm-30 mm.

4. The pole piece coating auxiliary assembly of claim 1, wherein:

the thickness of the thermal peeling adhesive tape (2) is 5 um-200 um.

5. The pole piece coating auxiliary assembly of any one of claims 1 to 4, wherein:

the width (a) of the thermal release tape does not exceed the width (b) of the margin;

the width (b) of the white-out area is 1 mm-50 mm;

the width (c) of the coating area is 5-300cm.

6. The utility model provides a pole piece coating unit, is used for the rolling including the unwinding roller that is used for unreeling pole piece (1) the wind-up roll of pole piece (1) to and coating die head (5), its characterized in that:

the pole piece coating apparatus further comprises a pole piece coating auxiliary assembly as claimed in any one of claims 1 to 5, the roller body (4) is located upstream of the coating die head (5), and the coating die head (5) is capable of coating the coating area (102) of the pole piece (1) and the thermal release tape (2) simultaneously.

7. The utility model provides a pole piece system of processing, includes stoving case (6), its characterized in that: the pole piece coating device of claim 6, wherein the unwinding roller and the roller body (4) are positioned at the upstream of the inlet of the drying box (6), the winding roller is positioned at the downstream of the outlet of the drying box (6), the thermal stripping adhesive tape (2) can be stripped from the blank area (101) in the drying box (6), and the heating temperature in the drying box (6) is 50-150 ℃.

8. The pole piece processing system of claim 7, wherein:

the drying box (6) is internally provided with a plurality of blowing heads (605), the blowing heads (605) are used for blowing gas to the pole piece (1), and the blowing speed of the blowing heads (605) is greater than 0.2m/s.

9. The pole piece processing system of claim 7 or 8, wherein:

the pole piece processing system also comprises a recovery unit arranged in the drying box (6), and the recovery unit is provided with an adhesive layer (604);

the adhesive layer (604) is capable of adhering the thermal release tape (2) released from the margin (101).

10. The pole piece processing system of claim 9, wherein:

the recovery unit is a collection box (603) arranged below the pole piece (1), and the bonding layer (604) is arranged on the inner wall of the collection box (603).