Rolling device for dry-method pole piece film forming

Abstract

The utility model discloses a rolling device for dry-method pole piece film forming, which comprises a roller body and a material accommodating part arranged on the roller body, and a material accommodating space is formed between the material accommodating part and the working surface of the roller body. The utility model discloses a rolling device for dry-method pole piece film forming, which is provided with a material accommodating part, can relieve accumulation of materials, can calendaring the materials, remarkably improves production efficiency, reduces production cost, reduces influence on environment, and improves integral performance and quality of products.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a roller pressing device for dry electrode film formation. Background Technology

[0002] Electrode film formation methods are mainly divided into wet film formation processes and dry film formation processes. Traditional wet processes require the use of solvents, which are then removed by heating and drying. This process not only affects production efficiency but also increases production costs. In contrast, dry processes do not require solvents and directly form electrodes by hot-pressing a fibrous binder, active material, and current collector. This method not only improves production efficiency but is also more environmentally friendly.

[0003] In the preparation of dry electrodes, the control of raw material usage is crucial, as it directly affects the thickness and quality of the electrode film, thus influencing the overall performance of the electrode. However, traditional dry film-forming processes typically employ straight rollers and use a constant-width calendering process along the length direction, which easily leads to raw material accumulation and waste in the width direction. Furthermore, when using straight rollers for film formation, the rollers need to apply significant rolling pressure to calender the material into an electrode film. Because of this high rolling pressure, a large roller diameter is required to ensure rigidity. The minimum rolling thickness of the roller is related to its diameter. In dry electrode preparation, a large roller diameter for straight rollers limits the minimum rollable thickness, thus affecting the preparation of the electrode sheet.

[0004] Therefore, there is an urgent need for a roller pressing device for dry electrode film formation to solve the above problems. Utility Model Content

[0005] In view of this, the present invention proposes a roller pressing device for dry electrode film formation, which significantly improves production efficiency, reduces production costs, minimizes environmental impact, and enhances the overall performance and quality of the product. The technical solution of the present invention is as follows:

[0006] This utility model proposes a roller pressing device for dry electrode film formation, including a roller body and a material receiving part disposed on the roller body, wherein a material receiving space is formed between the material receiving part and the working surface of the roller body.

[0007] Specifically, the roller body is an arc-shaped roller, and the cross-section of the material receiving part along the axial direction of the roller body is an arc surface.

[0008] Optionally, the material receiving portion of the roller has a triangular or trapezoidal cross-section along the axial direction of the roller.

[0009] Specifically, the arc-shaped roller is a concave arc-shaped roller, and the diameter of the arc-shaped roller gradually increases from the middle to both sides.

[0010] Optionally, the arc-shaped roller is a constant-diameter arc-shaped roller, with the diameter of the arc-shaped roller remaining unchanged, and the whole roller presenting an arc shape.

[0011] Specifically, the difference between the maximum and minimum radial section diameters of the concave arc-shaped roller is 1–20 μm.

[0012] Specifically, the roller pressing device further includes a rotating shaft that is connected through the roller body.

[0013] Specifically, the roller pressing device further includes a heating device, which is disposed at the rotating shaft.

[0014] Specifically, the roller pressing device further includes a temperature detection device, which is located on the inner wall of the roller body.

[0015] Specifically, the roller pressing device further includes a drive device and is drivenly connected to the rotating shaft.

[0016] The advantages of this utility model are as follows:

[0017] 1. The roller pressing device of this utility model includes a material receiving part. The cross-section of the material receiving part can be arc-shaped, triangular, trapezoidal, etc. This design can reduce the accumulation of raw materials and calender the raw materials, thereby improving the uniformity and quality of film formation.

[0018] 2. This utility model is equipped with a heating device and a temperature detection device, which are respectively installed on the inner wall of the rotating shaft and the roller. By precisely controlling the temperature, the material properties are kept stable during the film formation process, thereby improving production efficiency and finished product quality. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Identical parts are indicated by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "bottom surface," "top surface," "inner," and "outer" refer to directions toward or away from the geometric center of a specific part, respectively.

[0021] Figure 1 This is an overall structural diagram of an embodiment of the present utility model;

[0022] Figure 2This is a cross-sectional view of an embodiment of the present utility model;

[0023] Figure 3 This is a schematic diagram of the concave arc-shaped roller in an embodiment of this utility model;

[0024] Figure 4 This is a schematic diagram of the equal-diameter arc-shaped roller in an embodiment of the present invention;

[0025] The meanings of the reference numerals in the above figures are as follows:

[0026] 1. Material receiving section;

[0027] 2. Concave arc-shaped roller;

[0028] 3. Shaft;

[0029] 4. Heating device;

[0030] 5. Roller body;

[0031] 6. Working face. Detailed Implementation

[0032] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0033] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in the detailed description is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having” and any variations thereof in the specification, claims and foregoing description of the invention are intended to cover non-exclusive inclusion.

[0034] In the description of the specific embodiments of this utility model, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this utility model, "multiple" means two or more, unless otherwise explicitly defined.

[0035] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0036] In the description of this utility model embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this utility model, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0037] Throughout this invention, numerical values ​​represent approximate measurements or limits of a range to cover minute deviations from a given value, as well as embodiments having approximately the mentioned value and embodiments having the exact mentioned value. Except for the working examples provided at the end of the detailed description, all numerical values ​​of parameters, quantities, or conditions in the appended claims should be understood to be modified in all cases by the term “about,” regardless of whether “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows for some minute inaccuracy that is somewhat close to the exact value of the value; approximately or reasonably close to the value; almost. If the inaccuracy provided by “about” is not otherwise understood in this common sense in the art, then “about” as used in this invention at least indicates a variation that can be produced by common methods of measuring and using such parameters. For example, “about” may include a variation of less than or equal to 5%, optionally less than or equal to 4%, optionally less than or equal to 3%, optionally less than or equal to 2%, optionally less than or equal to 1%, optionally less than or equal to 0.5%, and in some respects, optionally less than or equal to 0.1%.

[0038] Additionally, the disclosure of the range includes the disclosure of all values ​​across the entire range and the disclosure of further subdivided ranges, including the endpoints and subranges given for these ranges.

[0039] The embodiments of the present invention will be described in more detail below through examples. It should be noted that the embodiments of the present invention are not limited to these examples.

[0040] Electrode film formation methods are mainly divided into wet film formation processes and dry film formation processes. In the traditional wet process, during electrode manufacturing, binders, conductive agents, and other substances are first mixed and stirred. Then, active materials are added and thoroughly stirred and dispersed. Finally, an appropriate amount of solvent is added to adjust the viscosity for coating. The use of solvent brings several problems. First, the solvent needs to be removed through a heating and drying process, which not only consumes a lot of energy and reduces production efficiency but also significantly increases production costs. Furthermore, the environmental pollution caused by solvent evaporation is becoming increasingly serious and does not meet modern environmental protection requirements.

[0041] To overcome these shortcomings of wet processes, dry film-forming processes have emerged. Dry processes eliminate the need for solvents, directly bonding fibrous binders and active materials to the current collector via hot pressing to form the electrode. This method not only avoids the use of solvents and the corresponding drying steps, significantly improving production efficiency, but also reduces environmental pollution, making it more environmentally friendly.

[0042] However, even dry processes face some challenges. First, precise control of raw material usage is crucial in dry electrode fabrication. The amount of raw materials directly affects the thickness and quality of the electrode film, thus influencing its electrochemical performance. Traditional dry film fabrication processes typically employ linear roller calendering, using a uniform width process along the length. While simple, this method has some drawbacks in practice.

[0043] First, in the linear roll calendering process, a large pressure is required to ensure uniform material distribution on the current collector. This not only increases equipment wear but also increases energy consumption and reduces production efficiency. Second, in the width direction, it easily leads to raw material accumulation and waste. Due to uneven raw material distribution, it is difficult to maintain consistent electrode thickness and quality, affecting the performance and consistency of the final product. Moreover, when using linear pressure rollers for calendering, the required pressure necessitates a larger roller diameter to ensure roller rigidity. However, a larger roller diameter affects the minimum thickness of the electrode film that can be calendered, thus impacting electrode performance.

[0044] Therefore, this application discloses a roller pressing device for dry electrode film formation that can solve the above problems.

[0045] In one specific embodiment, such as Figures 1-2As shown, a roller pressing device for dry electrode film formation includes a roller body 5 and a material receiving part 1 disposed on the roller body 5. A material receiving space is formed between the material receiving part 1 and the working surface 6 of the roller body 5. The material receiving part 1 has the functions of pre-pressing and storing material, and has low requirements for the precision control of material feeding, thus avoiding material accumulation and waste. This invention ensures that the raw material does not accumulate during the calendering process and can be evenly distributed, thereby guaranteeing the quality of the calendered electrode film.

[0046] Specifically, the roller body 5 is an arc-shaped roller, and the cross-section of the material receiving part 1 along the axial direction of the roller body 5 is an arc surface. This arc-shaped design helps to improve the distribution of raw materials on the roller body 5, reduce accumulation, and improve the uniformity and quality of film formation.

[0047] Optionally, the material receiving portion 1 of the roller body 5 has a triangular or trapezoidal cross section along the axial direction of the roller body 5. This can optimize the stacking and distribution of raw materials, further reduce material waste, and ensure consistent thickness and stable quality of the electrode film.

[0048] Specifically, such as Figure 3 As shown, the arc roller is a concave arc roller 2. The diameter of the arc roller gradually increases from the middle to both sides. This design helps to better control the material distribution during the calendering process, making the thickness of the electrode film more uniform, while reducing the pressure required for the roller body 5.

[0049] Optionally, such as Figure 4 As shown, the arc roller is a constant diameter arc roller with an overall arc shape. This design can maintain a stable distribution of material on the roller body 5 and improve the film formation quality and consistency of the electrode film.

[0050] Specifically, the difference between the maximum and minimum radial cross-sectional diameters of the concave arc roller 2 is 1 to 20 μm. This precise radial difference control can effectively improve the material uniformity and quality during the film formation process.

[0051] Specifically, the rolling device also includes a rotating shaft 3, which is connected through the roller body 5. The rotating shaft 3 enables the rolling device to operate stably, ensuring continuity and stability during the calendering process, and helping to improve production efficiency and film quality.

[0052] Specifically, the roller pressing device also includes a heating device 4, which is located at the rotating shaft 3.

[0053] In some embodiments, the heating device 4 can be located inside the rotating shaft 3 or on the outer wall of the rotating shaft 3, so that the material can be better processed into a film. Precise temperature control helps to optimize the performance of the binder and active substances, and ensures the stability of the film formation process and product quality.

[0054] Specifically, the roller pressing device also includes a temperature detection device, which is located on the inner wall of the roller body 5.

[0055] The temperature detection device can monitor the temperature of the roller, making it convenient to adjust the heating device 4 according to the actual production temperature requirements, and preventing temperature fluctuations from affecting the quality of the electrode film.

[0056] Specifically, the roller pressing device also includes a drive device and a drive connection to the rotating shaft 3. The roller pressing device is used to drive the roller body 5 to rotate, and can operate at different speeds and pressures, providing flexible production conditions, meeting different production needs, and improving film forming efficiency and quality.

[0057] When using this device to prepare dry electrode films, the material is first fed into the material receiving section of the device. A vibrating feeder can be used as the material feeding device. The drive device is started, which drives the rotating shaft 3 and then the roller 5 to rotate, so that the material is gradually calendered in the material receiving section 1 of the concave arc roller 2. During the calendering process, the heating device can be activated to heat the material to ensure that it is better calendered into film. The device can be set up in multiple groups according to the needs of the film to be prepared, and the curvature of the multiple groups can be adjusted as needed.

[0058] It should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A roller pressing device for dry electrode film formation, characterized in that, The roller pressing device includes a roller body and a material receiving part disposed on the roller body, and a material receiving space is formed between the material receiving part and the working surface of the roller body.

2. The roller pressing device for dry electrode film formation according to claim 1, characterized in that, The roller body is an arc-shaped roller, and the cross-section of the material receiving part along the axial direction of the roller body is an arc surface.

3. The roller pressing device for dry electrode film formation according to claim 1, characterized in that, The material receiving portion of the roller has a triangular or trapezoidal cross-section along the axial direction of the roller.

4. The roller pressing device for dry electrode film formation according to claim 2, characterized in that, The arc-shaped roller is a concave arc-shaped roller, and the diameter of the arc-shaped roller gradually increases from the middle to both sides.

5. The roller pressing device for dry electrode film formation according to claim 2, characterized in that, The arc-shaped roller is a constant diameter arc-shaped roller, and the overall shape is arc-shaped.

6. The roller pressing device for dry electrode film formation according to claim 4, characterized in that, The difference between the maximum and minimum radial section diameters of the concave arc-shaped roller is 1–20 μm.

7. The roller pressing device for dry electrode film formation according to claim 1, characterized in that, The roller pressing device also includes a rotating shaft, which is connected through the roller body.

8. The roller pressing device for dry electrode film formation according to claim 7, characterized in that, The roller pressing device also includes a heating device, which is located at the rotating shaft.

9. The roller pressing device for dry electrode film formation according to claim 8, characterized in that, The roller pressing device also includes a temperature detection device, which is located on the inner wall of the roller.

10. The roller pressing device for dry electrode film formation according to claim 7, characterized in that, The roller pressing device also includes a drive unit, which is connected to the rotating shaft drive.

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