Pole piece pre-rolling device for coating equipment

Abstract

The utility model relates to a pole piece pre-rolling device for coating equipment, which comprises a rolling roller, the rolling roller is arranged at an outlet of a double-sided coating oven and behind an inherent flattening roller of the coating equipment, and the rolling roller consists of two rollers which are arranged up and down; a plurality of sleeve films are additionally arranged on the rolling roller at the position of a coated tab blank area of the pole piece, and certain extension pretreatment is carried out on the foil at the position of the coated tab blank area; the device has the advantages that the structure is simple, pole piece rebound reduction is promoted, and the problem of pole piece cold pressing and rolling is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of coating equipment, and particularly relates to a pre-rolling device for electrode sheets on coating equipment. Background Art

[0002] After the positive and negative electrode sheets are coated and enter the rolling process, they are rolled to reach the corresponding electrode sheet thickness and compaction according to the process requirements. Currently, the main method used is one-time cold rolling, which easily causes a large thickness rebound of the electrode sheet after rolling, especially for the negative electrode sheet; second, cold rolling requires a large rolling force from the rollers in the rolling process to compress the thickness of the electrode sheet to the thickness required by the process; third, cold rolling performs poorly in terms of the bonding force between the electrode sheet coating material and the current collector, powder shedding during the charge and discharge cycle of the battery, and the cycle life of the battery. Therefore, it is very necessary to provide a pre-rolling device for electrode sheets on coating equipment that has a simple structure, promotes the reduction of electrode sheet rebound, and improves the problems of cold rolling of electrode sheets. Summary of the Invention

[0003] The purpose of the utility model is to overcome the deficiencies of the prior art and provide a pre-rolling device for electrode sheets on coating equipment that has a simple structure, promotes the reduction of electrode sheet rebound, and improves the problems of cold rolling of electrode sheets.

[0004] The purpose of the utility model is achieved as follows: A pre-rolling device for electrode sheets on coating equipment includes a rolling roller. The rolling roller is placed at the outlet of the double-sided coating oven and behind the flattening roller inherent in the coating equipment. The rolling roller is composed of two rollers arranged up and down. Moreover, multiple films are added to the position of the blank area of the coating electrode tab on the electrode sheet, and certain stretching pretreatment is performed on the foil material itself at the position of the blank area of the coating electrode tab.

[0005] The blank area of the coating electrode tab is located between the coating dressing areas. The coating dressing areas are located at the outlet of the double-sided coating oven and between the two upper and lower rollers of the rolling roller.

[0006] The thickness of the film is equal to the thickness of the electrode sheet after pre-rolling minus the thickness of the foil material minus 10 μm.

[0007] The pressures exerted by the two upper and lower steel rollers of the rolling roller on the positive and negative electrode sheets need to be different, that is, the force exerted on the positive electrode sheet is less than the force exerted on the negative electrode sheet.

[0008] The two upper and lower rollers of the rolling roller are both hollow rollers.

[0009] The thickness of the hard chromium layer on the surface of the rolling roller is ≥0.3 mm.

[0010] The surface roughness of the rolling roller is < 0.4μm, there is no pinhole phenomenon, the hardness is ≥ HRC58, the diameter is 160mm, the circular runout is < 2μm Ra0.4, and the straightness is 1.5μm.

[0011] The beneficial effects of the present utility model: The present utility model is a pre-rolling device for pole pieces on a coating device, which improves the disadvantages of the current single cold rolling method in the rolling process. During use, the rolling roller is used in the following way: after double-sided coating, the pole piece comes out of the oven and passes through the flattening roller at the oven outlet, and then reaches the rolling roller. At this time, the upper and lower rollers of the rolling roller close and apply a certain pressure to pre-roll the passing pole piece. At this time, because the pole piece just comes out of the oven and still has residual heat, it is beneficial for pre-rolling, thus reducing the disadvantages of cold rolling in the rolling process to a certain extent. That is to say, placing the rolling roller near the oven outlet is beneficial to promoting the reduction of pole piece rebound, reducing the rolling force of the cold rolling process of the roller, enhancing the bonding force between the pole piece coating material and the current collector, reducing the occurrence of powder dropping during the charge and discharge cycle of the battery, improving the cycle life of the battery, and reducing the cost of the cold rolling process; The present utility model has the advantages of simple structure, promoting the reduction of pole piece rebound, and improving the problem of cold-rolled pole pieces. Description of the Drawings

[0012] Figure 1 It is a schematic diagram of the coating and rolling structure of the present utility model.

[0013] In the figure: 1. Double-sided coating oven outlet; 2. Flattening roller; 3. Rolling roller; 4. Sleeve film; 5. Coating dressing area; 6. Coating tab blank area. Specific Embodiments

[0014] The following further describes the present utility model with reference to the drawings. Embodiment

[0015] As Figure 1 shown, a pre-rolling device for pole pieces on a coating device includes a rolling roller 3. The rolling roller 3 is placed at the double-sided coating oven outlet 1 and behind the inherent flattening roller 2 of the coating device. The rolling roller 3 is composed of two upper and lower rollers, and multiple sleeve films 4 are added to the rolling roller 3 at the position of the coating tab blank area 6 of the pole piece to perform a certain stretching pretreatment on the foil material itself at the position of the coating tab blank area 6.

[0016] The utility model relates to a pre-rolling device for electrode sheets on a coating device, which improves the drawbacks of the current single cold rolling process in the rolling process. During use, the method of using the rolling roller 3 is that after double-sided coating, the electrode sheet comes out of the oven and passes through the flattening roller 2 at the oven outlet, and then reaches the rolling roller 3. At this time, the upper and lower rollers of the rolling roller 3 are closed and a certain pressure is applied to pre-roll the passing electrode sheet. At this time, because the electrode sheet has just come out of the oven and still has residual heat, it is beneficial for pre-rolling, thereby reducing the drawbacks of cold rolling in the rolling process to a certain extent. That is to say, placing the rolling roller 3 near the oven outlet 1 is beneficial to promoting the reduction of electrode sheet rebound, reducing the cold rolling force in the rolling process, enhancing the bonding force between the electrode sheet coating material and the current collector, reducing the occurrence of powder falling during the charge and discharge cycle of the battery, improving the cycle life of the battery, and reducing the cost of the cold rolling process; the utility model has the advantages of simple structure, promoting the reduction of electrode sheet rebound, and improving the problems of cold-rolled electrode sheets. Embodiment

[0017] As Figure 1 shown, a pre-rolling device for electrode sheets on a coating device includes a rolling roller 3. The rolling roller 3 is placed at the outlet 1 of a double-sided coating oven and is located behind the inherent flattening roller 2 of the coating device. The rolling roller 3 is composed of two rollers arranged up and down, and three wrapping films 4 are added to the rolling roller 3 at the position of the blank area 6 of the coating tab of the electrode sheet to perform a certain stretching pretreatment on the foil material itself at the position of the blank area 6 of the coating tab.

[0018] The blank area 6 of the coating tab is located between the coating dressing areas 5, and the coating dressing areas 5 are located at the outlet 1 of the double-sided coating oven and between the upper and lower rollers of the rolling roller 3.

[0019] The thickness of the wrapping film 4 is equal to the thickness of the electrode sheet after pre-rolling minus the thickness of the foil material minus 10 μm.

[0020] In this embodiment, the wrapping film 4 is a wrapping film made of a polymer material.

[0021] The pressures exerted by the upper and lower steel rollers of the rolling roller 3 on the positive and negative electrode sheets need to be different, that is, the force exerted on the positive electrode sheet is less than the force exerted on the negative electrode sheet.

[0022] In this embodiment, the pressures exerted by the upper and lower steel rollers of the rolling roller 3 on the positive and negative electrode sheets need to be different. According to the properties of the electrode sheet coating material, generally speaking, the force exerted on the positive electrode sheet is less than the force exerted on the negative electrode sheet (note: the coating speed of the coating device itself will also affect the effect of the rolling roller 3 to a certain extent, so the specific setting of relevant parameters needs to be debugged and run-in during the use of the device).

[0023] The materials and specifications of the upper and lower rollers of the rolling roller 3 are special steel, hollow rollers.

[0024] The thickness of the hard chromium layer on the surface of the rolling roller 3 is ≥ 0.3 mm.

[0025] In this embodiment, two layers of coatings need to be plated on the surface of the rolling roller 3. One layer is a hard chromium layer, and the other layer is a high-temperature resistant layer made of a polymer material.

[0026] The surface roughness of the rolling roller 3 is < 0.4 μm, there is no pinhole phenomenon, the hardness is ≥ HRC58, the diameter is 160 mm, the circular runout is < 2 μm Ra0.4, and the straightness is 1.5 μm.

[0027] In this embodiment, the materials and specifications of the upper and lower rollers of the rolling roller 3 are special steel, hollow rollers, with a hard chromium coating on the surface. The coating thickness is ≥ 0.3 mm, the surface roughness is < 0.4 μm, there is no pinhole phenomenon, the hardness is ≥ HRC58, the diameter is 160 mm, the circular runout is < 2 μm Ra0.4, and the straightness is 1.5 μm (note: the specifications of this rolling roller 3 refer to the specifications of the steel rollers used in current coating equipment); at the same time, a high-temperature resistant film made of a polymer material is plated on it, that is, two layers of coatings need to be plated on the surface of the rolling roller 3. One layer is a hard chromium layer, and the other layer is a high-temperature resistant layer, and it cannot cause pollution to the electrode sheet.

[0028] The present utility model is a pre-rolling device for electrode sheets on a coating equipment, which improves the drawbacks existing in the current single cold rolling method in the rolling process. In use, the rolling roller 3 is used in such a way that after double-sided coating, the electrode sheet comes out of the oven and passes through the flattening roller 2 at the oven outlet, and then reaches the rolling roller 3. At this time, the upper and lower rollers of the rolling roller 3 are closed and a certain pressure is applied to pre-roll the passing electrode sheet. At this time, because the electrode sheet has just come out of the oven and still has residual heat, it is beneficial for its pre-rolling, thereby reducing the drawbacks of cold rolling in the rolling process to a certain extent. That is to say, placing the rolling roller 3 near the oven outlet 1 is beneficial for promoting the reduction of electrode sheet rebound, reducing the rolling force of the cold roller in the rolling process, enhancing the bonding force between the electrode sheet coating material and the current collector, reducing the occurrence of powder falling during the charge and discharge cycle of the battery, improving the cycle life of the battery, and reducing the cost of the cold rolling process; the present utility model adopts the placement position of the rolling roller at the outlet of the double-sided coating oven, behind the inherent flattening roller of the coating equipment, and the rolling roller applies different forces to the positive and negative electrode sheets, which can effectively improve the problems of the electrode sheets after cold rolling in the current rolling process; the present utility model has the advantages of simple structure, promoting the reduction of electrode sheet rebound, and improving the problems of cold-rolled electrode sheets.

Claims

1. A pre-rolling device for a pole piece on a coating device, which comprises a rolling roller, and is characterized in that: The position of the rolling roller is placed at the outlet of the double-sided coating oven, behind the flattening roller inherent in the coating equipment. The rolling roller consists of two rollers arranged vertically, and multiple membranes are added to the positions of the blank areas of the coating tabs on the electrode foil on the rolling roller to perform pre-extension treatment on the foil material itself in the blank areas of the coating tabs.

2. The pre-rolling device for the pole piece on the coating equipment according to claim 1, wherein: The blank area of the coating tab is located between the coating dressing areas, and the coating dressing areas are located at the outlet of the double-sided coating oven and between the two upper and lower rollers of the rolling roller.

3. The pre-rolling device for the pole piece on the coating equipment according to claim 2, characterized in that: The thickness of the membrane is equal to the thickness of the electrode foil after pre-rolling minus the thickness of the foil material minus 10 μm.

4. The pre-rolling device for the electrode sheet on the coating equipment according to claim 2, characterized in that: The pressures exerted by the two upper and lower steel rollers of the rolling roller on the positive and negative electrode foils need to be different, that is, the force exerted on the positive electrode foil is less than the force exerted on the negative electrode foil.

5. The pre-rolling device for the pole piece on the coating equipment according to claim 4, characterized in that: Both of the two upper and lower rollers of the rolling roller are hollow rollers.

6. The pre-rolling device for the pole piece on the coating equipment according to claim 5, characterized in that: The thickness of the hard chromium layer on the surface of the rolling roller is ≥ 0.3 mm.

7. The pre-rolling device for the pole piece on the coating equipment according to claim 6, characterized in that: The surface roughness of the rolling roller is < 0.4 μm, there is no pinhole phenomenon, the hardness is ≥ HRC58, the diameter is 160 mm, the circular runout is < 2 μm Ra0.4, and the straightness is 1.5 μm.

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