Pole piece preparation device and preparation system

Abstract

The utility model provides a pole piece preparation device and a preparation system. The pole piece preparation device comprises a rolling unit, a feeding unit and an electrostatic generation unit with a high-voltage positive electrode and a high-voltage negative electrode, the rolling unit comprises rollers rotationally arranged on the two sides of the current collector respectively; the feeding units are arranged on at least one side of the current collector and used for spraying powder to the rollers on the same side, the feeding units are electrically connected with the high-voltage negative electrode, the rollers arranged on the same side as the feeding units are electrically connected with the high-voltage positive electrode and are grounded, and the powder sprayed by the feeding units can be adsorbed on the rollers by static electricity and is rolled on the current collector by the two rollers to form a pole piece film. According to the pole piece preparation device disclosed by the utility model, powder is uniformly adsorbed on the rollers by static electricity, and the powder is rolled on the current collector through the two rollers, so that a pole piece film can be formed on the current collector, the uniformity of the pole piece film is favorably improved, and the pole piece film can be effectively prevented from being broken; therefore, the performance and the production efficiency of the pole piece are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of pole piece preparation equipment, and in particular to a pole piece preparation device. The utility model also relates to a preparation system provided with the pole piece preparation device. Background Art

[0002] As people's environmental awareness increases, the development and application of lithium-ion batteries have been improved. Square lithium-ion batteries have become the main products of new energy companies due to their advantages such as high packaging reliability, good tolerance, and relatively simple grouping. The battery process mainly includes slurrying, coating, rolling, slitting, assembly, and formation. The mainstream coating process is wet coating, which requires mixing the electrode material solvent for coating. The slurry needs to be dried during the coating process, and the solvent recovery cost is high. Dry coating eliminates the use of solvents, which greatly reduces the cost and process flow. Dry coating will definitely become the mainstream process for lithium battery coating.

[0003] The traditional wet process is to mix the active material, conductive agent, and binder in a solvent in proportion, and then apply it to the current collector surface as required through a slit coating die and roll it. The dry process is to mix the active particles and conductive agent evenly and then add the binder, form a self-supporting film under the fibrillation of the binder, and finally roll it to cover the current collector surface. However, the self-supporting film formed by the existing binder under the fibrillation of the binder is uneven, and the formed support film is easily broken due to the process tension fluctuation, which has a great impact on mass production efficiency. Utility Model Content

[0004] In view of this, the utility model aims to provide a pole piece preparation device to improve the film forming effect of the pole piece film and to help improve the production efficiency of the pole piece.

[0005] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0006] A pole piece preparation device comprises a rolling unit, a feeding unit, and a static electricity generating unit having a high-voltage positive electrode and a high-voltage negative electrode;

[0007] The rolling unit comprises rollers which are respectively rotatably arranged on both sides of the current collector;

[0008] The feeding unit is arranged on at least one side of the current collector, and is used to spray powder to the roller on the same side, and the feeding unit is electrically connected to the high-voltage negative electrode, and the roller arranged on the same side of the feeding unit is electrically connected to the high-voltage positive electrode and grounded. The powder sprayed by the feeding unit can be electrostatically adsorbed on the roller and pressed onto the current collector by the two rollers to form a pole piece film.

[0009] Furthermore, a heating part is provided in at least the roller arranged on the same side as the feeding unit.

[0010] Furthermore, the heating unit includes a heating tube arranged in the rolling roller.

[0011] Furthermore, the feeding units are arranged on both sides of the current collector corresponding to the rollers, and the static electricity generating units are arranged in one-to-one correspondence with the feeding units and are respectively electrically connected to the feeding units and the pressing rollers on the same side.

[0012] Furthermore, the surface roughness of the roller arranged on the same side as the feeding unit is greater than the surface roughness of the current collector.

[0013] Furthermore, the feeding unit includes an electrostatic spray gun and a material bin connected to the electrostatic spray gun.

[0014] Furthermore, the electrostatic generating unit includes an electrostatic generator.

[0015] Compared with the prior art, the utility model has the following advantages:

[0016] The pole piece preparation device described in the utility model is electrically connected to the high-voltage negative electrode of the static electricity generating unit by the feeding unit, and the roller is electrically connected to the high-voltage positive electrode of the static electricity generating unit and grounded, so that an electrostatic field can be formed between the feeding unit and the roller, so that the powder is uniformly adsorbed on the roller by electrostatic electricity, and the powder is rolled onto the collector by the two rollers, so that a pole piece film can be formed on the collector. Compared with the traditional processing method of forming a self-supporting film, it is not only beneficial to improve the uniformity of the pole piece film, but also can effectively avoid the fracture of the pole piece film, thereby helping to improve the performance and production efficiency of the pole piece.

[0017] In addition, by setting a heating part in the roller, it is beneficial to improve the composite effect and efficiency of the electrode film on the current collector. The heating tube has a simple structure, is easy to arrange and implement in the roller, and has a good heating effect. The feeding unit is set on both sides of the current collector, and the static electricity generating unit is electrically connected to the feeding unit and the roller on the same side, which is beneficial to form the electrode film on both surfaces of the current collector at the same time, thereby further improving the preparation efficiency of the electrode.

[0018] In addition, the surface roughness of the roller is greater than that of the current collector, which is conducive to the powder being pressed on the surface of the current collector as the roller rotates. The electrostatic spray gun and the silo are combined to facilitate the spraying of the powder on the roller, and the products of the electrostatic spray gun and the silo are mature and easy to implement. The electrostatic generator has a simple structure and is easy to arrange and implement, which is conducive to the electrostatic adsorption of the powder on the roller.

[0019] In addition, another object of the present invention is to provide a pole piece preparation system, including a conveying unit for conveying a current collector, and the pole piece preparation device as described above.

[0020] Furthermore, the conveying unit includes a rotatably arranged unwinding roller and a winding roller, the unwinding roller is used for unwinding the current collector, and the winding roller is used for winding the electrode sheet.

[0021] The pole piece preparation system described in the utility model conveys the current collector through the conveying unit, and the pole piece preparation device as described above is conducive to compounding the powder on the current collector during the current collector conveying process, thereby facilitating improving the production efficiency and performance of the pole piece.

[0022] In addition, the unwinding roller and the winding roller are simple in structure, easy to implement, and convenient for unwinding the current collector and winding the electrode sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0024] Figure 1 It is a structural schematic diagram of the electrode preparation device described in an embodiment of the utility model.

[0025] Description of reference numerals:

[0026] 1. Current collector; 2. Pole piece; 3. Roller; 4. Electrostatic spray gun; 5. Unwinding roller; 6. Rewinding roller. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0028] In the description of the present invention, it should be noted that if there are terms indicating orientation or positional relationship such as "upper", "lower", "inner", "back", etc., they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if there are terms such as "first", "second", etc., they are also used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0029] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0030] The present embodiment relates to a pole piece preparation device, including a rolling unit, a feeding unit, and an electrostatic generating unit having a high-voltage positive electrode and a high-voltage negative electrode.

[0031] The rolling unit includes rollers 3 that are respectively rotated on both sides of the current collector 1. The feeding unit is arranged on at least one side of the current collector 1, and is used to spray powder to the rollers 3 on the same side. The feeding unit is electrically connected to the high-voltage negative electrode, and the roller 3 arranged on the same side of the feeding unit is electrically connected to the high-voltage positive electrode and grounded. The powder sprayed by the feeding unit can be electrostatically adsorbed on the rollers 3, and is rolled on the current collector 1 by the two rollers 3 to form a pole piece 2 film.

[0032] The electrode preparation device of this embodiment is electrically connected to the high-voltage negative electrode of the electrostatic generating unit through the feeding unit, and the roller 3 is electrically connected to the high-voltage positive electrode of the electrostatic generating unit and grounded. An electrostatic field can be formed between the feeding unit and the roller 3, so that the powder is uniformly electrostatically adsorbed on the roller 3, and the powder is rolled onto the collector 1 by the two rollers 3, so that the electrode 2 film can be formed on the collector 1. Compared with the traditional processing method of forming a self-supporting film, it is not only beneficial to improve the uniformity of the electrode 2 film, but also can effectively avoid the fracture of the electrode 2 film, thereby helping to improve the performance and production efficiency of the electrode 2.

[0033] Based on the above overall introduction, an exemplary structure of the electrode preparation device described in this embodiment is as follows: Figure 1 As shown in , two rollers 3 are relatively rotatably arranged on the upper and lower sides of the current collector 1, and the two ends of the rollers 3 are specifically rotatably arranged on the frame to roll the powder onto the current collector 1 to form a film of the pole piece 2. In this embodiment, the active material conductive agent and the binder powder need to be pre-mixed, and the mixed powder is sprayed on the roller 3. In specific implementation, the specific composition of the powder can be determined according to the use requirements.

[0034] Preferably, a heating unit is provided in at least the roller 3 arranged on the same side as the feeding unit. The binder in the powder is easily adhered to the surface of the current collector 1 when heated, thereby forming a film of the electrode 2, which is beneficial to improving the production efficiency of the electrode 2. In specific implementation, the heating unit includes a heating tube arranged in the roller 3. The heating tube has a simple structure, is easy to arrange and implement in the roller 3, and has a good heating effect.

[0035] In this embodiment, the surface roughness of the roller 3 used for electrostatically adsorbing the powder is greater than the surface roughness of the current collector 1. Such an arrangement is conducive to the powder rotating with the roller 3 and being rolled onto the surface of the current collector 1.

[0036] In order to further improve the production efficiency of the electrode sheet 2, the feeding units are arranged on both sides of the current collector 1 corresponding to each roller 3, and the static electricity generating units are arranged one by one with the feeding units, and are respectively electrically connected to the feeding units and the rollers on the same side. The feeding units are arranged on both sides of the current collector 1, and the static electricity generating units are electrically connected to the feeding units and the rollers 3 on the same side, which is conducive to forming the electrode sheet 2 film on both surfaces of the current collector 1 at the same time, thereby further improving the preparation efficiency of the electrode sheet 2.

[0037] As a preferred embodiment, the feeding unit in this embodiment includes an electrostatic spray gun 4 and a silo connected to the electrostatic spray gun 4. The electrostatic spray gun 4 here can be a product in the prior art, and the silo is used to store the mixed powder, which is transported to the electrostatic spray gun 4 via a first conveying pipe, and an external air source, such as compressed air, can be transported to the electrostatic spray gun 4 via a second conveying pipe, and the powder is sprayed toward the roller 3.

[0038] When implementing it, Figure 1 As shown in the figure, an electrostatic spray gun 4 is provided corresponding to each roller 3, and the width of its spray range is not less than the width of the current collector 1, so as to ensure that the width of the electrode sheet 2 film completely covers the current collector 1, thereby facilitating the uniformity of the electrode sheet 2. In order to improve the flexibility in use, the spray head on the electrostatic spray gun 4 is detachable, so as to facilitate the disassembly, replacement and maintenance of the spray head.

[0039] In this embodiment, the electrostatic generating unit includes an electrostatic generator, which can also be a product in the prior art, so as to form a strong electrostatic field between the electrostatic spray gun 4 and the roller 3. When the carrier gas (compressed air) transports the powder from the silo to the guide cup of the spray gun, dense charges are generated around it, so that the powder is negatively charged. Under the action of electrostatic force and compressed air, the powder can be uniformly adsorbed on the roller 3. After the roller 3 is heated, the powder is melted and solidified into a uniform, continuous and flat electrode 2 film, thereby improving the uniformity of the electrode 2.

[0040] In addition, this embodiment also relates to a pole piece preparation system, including a conveying unit for conveying the current collector 1, and the pole piece preparation device as above.

[0041] like Figure 1 As shown in the figure, the conveying unit includes a rotatably arranged unwinding roller 5 and a winding roller 6, the unwinding roller 5 is used to unwind the current collector 1, and the winding roller 6 is used to wind up the pole piece 2. Here, the unwinding roller 5 and the winding roller 6 are simple in structure, easy to implement, and convenient for unwinding the current collector 1 and winding up the pole piece 2.

[0042] The electrode preparation system of this embodiment, which transports the current collector 1 through a conveying unit, and the electrode preparation device as described above, is conducive to compounding the powder on the current collector 1 during the transportation of the current collector 1, thereby facilitating improving the production efficiency and performance of the electrode 2.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pole piece preparation device, characterized in that: It includes a rolling unit, a feeding unit, and an electrostatic generating unit having a high-voltage positive electrode and a high-voltage negative electrode; The rolling unit comprises rollers which are respectively rotatably arranged on both sides of the current collector; The feeding unit is arranged on at least one side of the current collector, and is used to spray powder to the roller on the same side, and the feeding unit is electrically connected to the high-voltage negative electrode, and the roller arranged on the same side of the feeding unit is electrically connected to the high-voltage positive electrode and grounded. The powder sprayed by the feeding unit can be electrostatically adsorbed on the roller and pressed onto the current collector by the two rollers to form a pole piece film.

2. The pole piece preparation device according to claim 1, characterized in that: A heating part is provided in at least the roller arranged on the same side as the feeding unit.

3. The pole piece preparation device according to claim 2, characterized in that: The heating part includes a heating tube arranged in the roller.

4. The pole piece preparation device according to claim 1, characterized in that: The feeding units are arranged on both sides of the current collector corresponding to the rollers, and the static electricity generating units are arranged one by one corresponding to the feeding units and are respectively electrically connected to the feeding units and the rollers on the same side.

5. The pole piece preparation device according to claim 1, characterized in that: The surface roughness of the roller arranged on the same side as the feeding unit is greater than the surface roughness of the current collector.

6. The pole piece preparation device according to claim 1, characterized in that: The feeding unit comprises an electrostatic spray gun and a material bin connected to the electrostatic spray gun.

7. The pole piece preparation device according to any one of claims 1 to 6, characterized in that: The static electricity generating unit includes a static electricity generator.

8. A pole piece preparation system, characterized in that: It comprises a conveying unit for conveying a current collector, and a pole piece preparation device as claimed in any one of claims 1 to 7.

9. The pole piece preparation system according to claim 8, characterized in that: The conveying unit comprises a rotatably arranged unwinding roller and a winding roller, wherein the unwinding roller is used for unwinding the current collector, and the winding roller is used for winding the pole piece.

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