Battery insulation sheet forming process

Abstract

The invention provides a battery insulation sheet forming process which comprises the following steps: S1, pretreatment: pouring raw materials into a hopper, and enabling a die head and a first compression roller to respectively move towards a second compression roller by a certain distance; s2, preheating and discharging are conducted, specifically, the raw materials in the hopper, a first pressing roller and a second pressing roller are heated, and the heated raw materials in the hopper flow to the position between the first pressing roller and the second pressing roller from a discharging opening through a die head; s3, hot press molding: rotating the first press roller and the second press roller, and hot-pressing the semi-solid raw material falling from the die head into a sheet-shaped semi-finished product; s4, rolling and cooling; and S5, obtaining a finished product. According to the battery insulation sheet forming process provided by the invention, a pretreatment link is utilized, and the die head is moved towards the second compression roller by a certain distance, so that a semi-cured raw material falls on the second compression roller and is stacked on the second compression roller, and a sheet-shaped semi-finished product generates certain stress; and the stress can effectively resist the stress caused by temperature difference, so that the sheet-shaped finished product passing through the cooling roller is kept flat.

Description

Technical Field

[0001] The invention relates to the technical field of insulating sheet production, and in particular to a battery insulating sheet molding process. Background Art

[0002] Insulating sheets play a role of separation in electrical or electronic equipment. They are mainly thin sheets made of polymer materials such as polyimide, phenolic resin, polypropylene, polycarbonate, etc., and have high insulation and high temperature resistance.

[0003] The battery cell is the main electric drive component in new energy electric vehicles. Insulating sheets are required in the battery cell to prevent electric energy from breaking through the battery cell. Therefore, the insulating sheets require high flatness and insulation effect.

[0004] However, in the production process of battery insulating sheets, the shrinkage of the insulating sheets is relatively high, so that after the insulating sheets are molded, the two sides of the insulating sheets are unevenly heated during transportation and cooling, which easily causes shrinkage and warping of the corners. Therefore, heavy objects are needed to press them down and statically shape them for a long time (usually 24-48 hours) to flatten the warped corners. Long shaping time will slow down the overall production process, thereby affecting the production efficiency of the battery cells. Summary of the invention

[0005] The purpose of the present invention is to solve the above problems in the prior art.

[0006] In order to achieve the above object, the present invention can be implemented by the following technical solutions: A battery insulation sheet forming process comprises the following steps:

[0007] S1, pretreatment: pour the raw materials into the hopper, and move the die head and the first pressing roller to the second pressing roller by a certain distance respectively;

[0008] S2, preheating and discharging: heating the raw material, the first pressing roller and the second pressing roller in the hopper, and making the heated raw material in the hopper flow from the discharge port to between the first pressing roller and the second pressing roller through the die head;

[0009] S3, hot pressing molding: the first pressing roller and the second pressing roller rotate to hot press the semi-solid raw material falling from the die head into a sheet-shaped semi-finished product;

[0010] S4, roller cooling: with the conveyance of the second pressing roller and the first pressing roller, the sheet-like semi-finished product is placed in contact with the cooling roller to cool the sheet-like semi-finished product;

[0011] S5, finished product: the finished product is inspected and packaged.

[0012] In the embodiment of the present invention, the S1 preprocessing includes the following steps:

[0013] S11, pre-processing of the first pressing roller: driving the first pressing roller toward or away from the second pressing roller by a certain distance through the first transmission member;

[0014] S12, die pretreatment: construct an axis on the second pressure roller, the axis is located between the first pressure roller and the second pressure roller, and is vertically fitted with the second pressure roller, and then the die is driven to move toward the first pressure roller through the second transmission member so that one side of the die outlet coincides with the axis.

[0015] In the embodiment of the present invention, the spacing between the first pressing roller and the second pressing roller in S2 is between 2 mm and 6 mm, and the spacing between the die feed openings is greater than the spacing between the first pressing roller and the second pressing roller.

[0016] In the embodiment of the present invention, the heating temperature of the hopper in S2 is controlled at 210° C. to 275° C., and the waiting time is 3 to 5 minutes.

[0017] In the embodiment of the present invention, the heating temperatures of the first pressing roller and the second pressing roller in S2 are consistent, and the temperatures are controlled at 230° C. to 265° C.

[0018] In the embodiment of the present invention, the first pressing roller and the second pressing roller in S3 have the same rotation speed and opposite rotation directions.

[0019] In the embodiment of the present invention, the temperature of the cooling roller in S4 is controlled at 60° C. to 95° C.

[0020] In the embodiment of the present invention, the second pressing roller in S4 is located between the cooling roller and the first pressing roller, and the distance between the cooling roller and the second pressing roller is equal to the distance between the first pressing roller and the second pressing roller.

[0021] In the embodiment of the present invention, the first transmission member in S11 includes a slider, a cylinder and a linkage block arranged at the output end of the cylinder, the linkage block is engaged with the slider, and the slider is fixed to the end of the first pressure roller.

[0022] In an embodiment of the present invention, the second transmission member in S12 comprises a support seat and a motor arranged on the support seat, a screw is arranged at the output end of the motor, and a support plate supporting the die head is threadedly connected to the screw.

[0023] Compared with the prior art, the advantages of the present application are: by utilizing the pretreatment step, the die head is moved a certain distance toward the second pressing roller, so that the semi-solidified raw material falls on the second pressing roller and accumulates on the second pressing roller to produce a certain stress on the sheet-like semi-finished product. When it is on the cooling roller, its stress can effectively resist the stress caused by the temperature difference, so that the sheet-like finished product passing through the cooling roller remains flat. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a schematic diagram of the roll forming process of the battery insulating sheet provided by the present invention;

[0025] Figure 2 It is a schematic diagram of the bonding between the conventional unloading area and the first pressing roller and the second pressing roller provided by the present invention;

[0026] Figure 3 It is a schematic diagram of the bonding between the unloading area and the first pressing roller and the second pressing roller provided by the present invention;

[0027] Figure 4 It is a schematic diagram of the forming of raw materials and the first pressing roller and the second pressing roller in the unloading area provided by the present invention;

[0028] Figure 5 It is a schematic diagram of the overall structure provided by the present invention;

[0029] Figure 6 It is a general plan view diagram provided by the present invention;

[0030] Figure 7 It is a schematic diagram of the positions of the die head, the first pressing roller and the second pressing roller provided by the present invention.

[0031] Description of reference numerals:

[0032] 1. First pressing roller; 11. Axis; 2. Unloading area; 21. First bonding surface; 22. Second bonding surface; 3. Second pressing roller; 4. Sheet semi-finished product; 5. Cooling roller; 6. Support frame; 61. First transmission member; 611. Linkage block; 612. Cylinder; 613. Slider; 62. Second transmission member; 621. Support seat; 622. Motor; 623. Support plate; 624. Screw; 63. Third transmission member; 631. Connecting block; 632. Transmission roller; 633. Spring; 634. Telescopic sleeve; 7. Die head. DETAILED DESCRIPTION

[0033] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention.

[0034] Embodiment 1

[0035] like Figure 1-4 As shown, a battery insulation sheet forming process includes the following steps:

[0036] S1, pretreatment: pour the raw material into the hopper, and move the die head 7 and the first pressing roller 1 to the second pressing roller 3 by a certain distance respectively;

[0037] S2, preheating and discharging: heating the raw material in the hopper, the first pressing roller 1 and the second pressing roller 3, and making the heated raw material in the hopper flow from the discharging port to between the first pressing roller 1 and the second pressing roller 3 through the die head 7;

[0038] S3, hot pressing: the first pressing roller 1 and the second pressing roller 3 rotate to hot press the semi-solid raw material falling from the die head 7 into a sheet-like semi-finished product 4;

[0039] S4, roller cooling: with the conveyance of the second pressing roller 3 and the first pressing roller 1, the sheet-like semi-finished product 4 is placed on the cooling roller 5 to cool the sheet-like semi-finished product 4;

[0040] S5, finished product: the finished product is inspected and packaged.

[0041] In the above technical solution: a material discharge area 2 is constructed at the discharge port of the die head 7, and the material discharge area 2 includes a first bonding surface 21 and a second bonding surface 22, and the sheet-like semi-finished product 4 refers to the insulation sheet after hot pressing;

[0042] like Figure 1 As shown, the insulating sheet forming process is a traditional method, and the die head 7 is located at the center of the distance between the first pressing roller 1 and the second pressing roller 3. When the die head 7 is unloading, the semi-solidified raw material falls from the unloading area 2 to the first pressing roller 1 and the second pressing roller 3. Relatively, the first bonding surface 21 and the second bonding surface 22 have the same contact area and stress generated with the first pressing roller 1 and the second pressing roller 3, respectively, so that when it is transported to the cooling roller 5 for cooling, since the second bonding surface 22 is not in contact with the cooling roller 5, a temperature difference is generated between the temperature of the first bonding surface 21 and the temperature of the second bonding surface 22. At this time, the sheet-like semi-finished product 4 will shrink toward the first bonding surface 21, resulting in the phenomenon of edge warping of the sheet-like semi-finished product 4 after molding.

[0043] like Figure 2 As shown, the die head 7 is moved toward the second pressing roller 3 for a certain distance so that the discharge port of the die head 7 is toward the second pressing roller 3. When the die head 7 discharges the material, the material will be accumulated above the second pressing roller 3, so that the second pressing roller 3 and the second bonding surface 22 complete surface contact and a certain stress is generated at the second bonding surface 22. At the same time, the second pressing roller 3 will take away part of the heat of the second bonding surface 22, while the first pressing roller 1 and the first bonding surface 21 are still in line contact, so the first bonding surface 21 cannot have part of the heat taken away by the first pressing roller 1; and when the first bonding surface 21 forms surface contact with the cooling roller 5, part of the heat of the first bonding surface 21 will be taken away by the cooling roller 5. Therefore, under the stress of the second bonding surface 22, the stress caused by the temperature difference on both sides of the sheet semi-finished product 4 can be effectively resisted, so that the sheet finished product 4 passing through the cooling roller 5 remains flat.

[0044] Furthermore, under the extrusion of the first pressure roller 1 and the second pressure roller 3, the material is deformed and compressed into a sheet under the action of a great extrusion force. During the forming process of the transmission insulating sheet, since the first pressure roller 1 and the second pressure roller 3 rotate at the same time, the material is conveyed and extruded, so that the material is adsorbed and accumulated on the first pressure roller 1 and the second pressure roller 3. In the present application, during the forming process of the insulating sheet, the material is accumulated on the second pressure roller 3, and the material is driven by the second pressure roller 3 and natural falling to form a smaller contact with the first pressure roller 1, and the material is extruded to reduce the phenomenon of adsorption and pushing.

[0045] Furthermore, the first pressing roller 1 and the cooling roller 5 both rotate counterclockwise, while the second pressing roller 3 rotates clockwise, so that when the material falls, the first pressing roller 1 and the second pressing roller 3 can push the material forward for extrusion, thereby improving the efficiency and effect of material forming.

[0046] As an embodiment further provided by the present invention, S1 pretreatment comprises the following steps:

[0047] S11, pre-processing of the first pressing roller 1: driving the first pressing roller 1 toward or away from the second pressing roller 3 by a certain distance through the first transmission member 61;

[0048] S12, pretreatment of the die head 7: construct an axis 11 on the second pressure roller 3, the axis 11 is located between the first pressure roller 1 and the second pressure roller 3, and is vertically fitted to the second pressure roller 3, and then the die head 7 is driven to move toward the first pressure roller 1 through the second transmission member 62, so that one side of the discharge port of the die head 7 coincides with the axis 11.

[0049] Specifically, the first transmission member 61 controls the spacing between the first pressing roller 1 and the second pressing roller 3, and the spacing is between 2 mm and 6 mm, and the spacing of the material discharge port of the die head 7 is greater than the spacing between the first pressing roller 1 and the second pressing roller 3. Further, the die head 7 is driven by the second transmission member 62 to move toward the second pressing roller 3, so that the first bonding surface 21 of the material discharge area 2 coincides with the axis 11, thereby completing the pretreatment process of the die head. The above-mentioned central axis 11 is as shown in Figure 4 The direction is perpendicular to the first pressing roller 1 from top to bottom, and the axis 11 is aligned with the leftmost side of the first pressing roller 1 .

[0050] As an embodiment further provided by the present invention, the heating temperature of the hopper is controlled at 210°C to 275°C before production, and wait for 3 to 5 minutes to soften the raw materials in the hopper and make them semi-solidified so that they can flow along the die head 7 to the unloading area 2. The heating temperatures of the first pressing roller 1 and the second pressing roller 3 are controlled to be relatively consistent (the temperature can be controlled between 230°C and 265°C), and the temperature difference between the two pressing rollers is small to improve the forming effect of the sheet semi-finished product 4. Subsequently, the sheet semi-finished product 4 passes through the cooling roller 5, and the temperature of the cooling roller 5 is controlled at 60°C to 95°C to cool the sheet semi-finished product 4.

[0051] Embodiment 2

[0052] like Figure 5-7 As shown, based on a battery insulation sheet forming process in embodiment 1 of the present invention, embodiment 2 of the present invention provides another battery insulation sheet forming process, wherein embodiment 2 will not hinder the independent implementation of the technical solution of the first embodiment.

[0053] As an embodiment further provided by the present invention, the first transmission member 61 in S11 includes a slider 613, a cylinder 612 and a linkage block 611 arranged at the output end of the cylinder 612, the linkage block 611 is engaged with the slider 613, and the slider 613 is fixed to the end of the first pressure roller 1.

[0054] Specifically, the cylinder 612 controls the linkage block 611 to slide on the support frame 6, thereby pushing the first pressing roller 1 close to or away from the second pressing roller 3 through the slider 613, so as to adjust the distance between the two pressing rollers, that is, the thickness of the insulating sheet after rolling. At the same time, the cylinder 612 can control the pre-pressure of the first pressing roller 1 toward the second pressing roller 3, thereby improving the rolling effect on the insulating sheet, wherein the support frame 6 supports the first pressing roller 1, the second pressing roller 3 and the cooling roller 5, and keeps the axes of the first pressing roller 1, the second pressing roller 3 and the cooling roller 5 on the same horizontal plane.

[0055] As an embodiment further provided by the present invention, the second transmission member 62 in S12 includes a support seat 621 and a motor 622 arranged on the support seat 621, and a screw 624 is arranged at the output end of the motor 622, and a support plate 623 supporting the die head 7 is threadedly connected to the screw 624.

[0056] Specifically, the output end of the motor 622 is connected to a reduction device to improve the stability of the rotation of the screw 624, that is, to make the moving distance of the die head 7 more precise. The above-mentioned support seat 621 is fixed on the support frame 6 by bolts to support the motor 622, the screw 624 and the die head 7. The motor 622 outputs to rotate the screw 624, and then the die head 7 slides toward the second pressure roller 3, so as to adjust the position of the discharge port of the die head 7. In this process, the die head 7 is controlled to move to the top of the second pressure roller 3 so that the first bonding surface 21 of the discharge area 2 coincides with the axis 11 constructed by the second pressure roller 3, so as to reduce the phenomenon of edge warping during the insulating sheet molding process.

[0057] Furthermore, a third transmission member 63 is provided on the support frame 6, and the third transmission member 63 includes a connecting block 631, a transmission roller 632, a telescopic sleeve 634 and a spring 633 arranged in the telescopic sleeve 634. The telescopic sleeve 634 includes a sleeve column and a telescopic rod sliding at the axis of the sleeve column, and the spring 633 is used to pull back the telescopic rod. The above-mentioned connecting block 631 is fixed to the end of the telescopic rod, and the transmission roller 632 is arranged on the connecting block 631. After the insulating sheet is extruded and formed, it will contact with the transmission roller 632. Under the pullback of the spring 633, the tightening effect of the insulating sheet is improved, so that the insulating sheet can better contact the first pressing roller 1, the second pressing roller 3 and the cooling roller 5, so as to improve the production effect of the insulating sheet.

[0058] The technical solution of the present invention provides a solution that is significantly different from the prior art to address the technical problem that the prior art solution is too single. The parts not involved in the technical solution of this application are the same as the prior art or can be implemented by using the prior art and will not be described in detail.

[0059] The technical solutions in the above embodiments have clearly and completely described the contents of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A battery insulation sheet forming process, characterized in that: The following steps are involved: S1， Pretreatment: Pour the raw materials into the hopper, and move the die head and the first pressing roller to the second pressing roller by a certain distance respectively; S2, preheating and discharging: heating the raw material, the first pressing roller and the second pressing roller in the hopper, and making the heated raw material in the hopper flow from the discharge port to between the first pressing roller and the second pressing roller through the die head; S3, hot pressing molding: the first pressing roller and the second pressing roller rotate to hot press the semi-solid raw material falling from the die head into a sheet-shaped semi-finished product; S4, roller cooling: with the conveyance of the second pressing roller and the first pressing roller, the sheet-like semi-finished product is placed in contact with the cooling roller to cool the sheet-like semi-finished product; S5, finished product: the finished product is inspected and packaged.

2. A battery insulation sheet forming process according to claim 1, characterized in that: The S1 pre-processing comprises the following steps: S11, pre-processing of the first pressing roller: driving the first pressing roller toward or away from the second pressing roller by a certain distance through the first transmission member; S12, die pretreatment: construct an axis on the second pressure roller, the axis is located between the first pressure roller and the second pressure roller, and is vertically fitted with the second pressure roller, and then the die is driven to move toward the first pressure roller through the second transmission member so that one side of the die outlet coincides with the axis.

3. A battery insulation sheet forming process according to claim 1, characterized in that: In the S2, the distance between the first pressing roller and the second pressing roller is between 2 mm and 6 mm, and the distance between the die feed openings is greater than the distance between the first pressing roller and the second pressing roller.

4. A battery insulation sheet forming process according to claim 1, characterized in that: The heating temperature of the hopper in S2 is controlled at 210° C. to 275° C., and the hopper is kept heated for 3 to 5 minutes.

5. A battery insulation sheet forming process according to claim 1, characterized in that: In S2, the heating temperatures of the first pressing roller and the second pressing roller are consistent, and the temperatures are controlled at 230°C to 265°C.

6. A battery insulation sheet forming process according to claim 1, characterized in that: In S3, the first pressing roller and the second pressing roller have the same rotation speed and opposite rotation directions.

7. A battery insulation sheet forming process according to claim 1, characterized in that: In the S4, the temperature of the cooling roller is controlled at 60°C to 95°C.

8. A battery insulation sheet forming process according to claim 1, characterized in that: The second pressing roller in S4 is located between the cooling roller and the first pressing roller, and the distance between the cooling roller and the second pressing roller is equal to the distance between the first pressing roller and the second pressing roller.

9. A battery insulation sheet forming process according to claim 2, characterized in that: The first transmission member in S11 includes a slider, a cylinder, and a linkage block arranged at the output end of the cylinder, the linkage block is engaged with the slider, and the slider is fixed to the end of the first pressure roller.

10. A battery insulation sheet forming process according to claim 2, characterized in that: The second transmission member in S12 comprises a support seat and a motor arranged on the support seat, a screw is arranged at the output end of the motor, and a support plate supporting the die head is threadedly connected to the screw.

Images