Lithium battery dry method electrode slurry preparation device and method

Abstract

The invention relates to the technical field of lithium battery manufacturing, in particular to a lithium battery dry method electrode slurry preparation device and method. The invention provides a lithium battery dry method electrode slurry preparation device. The device comprises a stirring tank, a stirring mechanism and a compression roller mechanism, the stirring tank is provided with a closed inner cavity for accommodating materials; the stirring mechanism comprises a main shaft rotatably arranged in the stirring tank, a planet carrier fixedly mounted on the main shaft, at least one stirring paddle mounted on the planet carrier and used for mixing materials, and at least one dispersing component mounted on the planet carrier and used for shearing and dispersing the materials; the compression roller mechanism comprises at least one compression roller, the compression roller is mounted on the planet carrier, and a gap for extruding and shearing materials is defined between the peripheral surface of the compression roller and the inner wall surface of the stirring tank. And the traditional step-by-step process is combined into one, so that the flow is obviously shortened, and the efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of lithium battery manufacturing technology, and in particular to an apparatus and method for preparing dry electrode slurry for lithium batteries. Background Technology

[0002] Dry electrode technology has become an important development direction in lithium battery manufacturing due to its advantages such as no solvent required, simplified process, and low cost. The core of this technology lies in the fiberization of the binder (such as PTFE) to form a three-dimensional network structure, thereby bonding the active material and conductive agent to form a self-supporting electrode film.

[0003] Currently, the mainstream dry electrode slurry (i.e., dry slurry) preparation processes are mainly divided into two categories: one is the high-intensity mechanical shearing method, which uses a high-speed mixer to vigorously stir the dry powder mixture, and the PTFE fibrillates through shear friction between the blades and the powder; the other is the rolling / calendering method, which is usually used as an independent or subsequent step, where the material is passed through high-pressure rollers and the PTFE fibers are further stretched using extrusion pressure. However, these existing technologies are mostly single or step-by-step processes. The shear force provided by the stirring process is relatively dispersed, resulting in limited fiberization efficiency and uniformity; while the subsequent independent rolling step can strengthen the fiber network, it is not organically integrated with the mixing process, leading to a long process flow and problems such as uneven fiberization and potential damage to the electrode pore structure by high pressure. Therefore, how to achieve efficient, uniform, and integrated dry electrode slurry preparation has become an urgent technical problem to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for preparing dry electrode slurry for lithium batteries, so as to solve the technical problems of low efficiency, uneven fiberization, and complex process flow caused by the separation of mixing and fiberization processes in the existing dry electrode slurry preparation process.

[0005] In a first aspect, the present invention provides a lithium battery dry electrode slurry preparation apparatus, comprising: a stirring tank, a stirring mechanism, and a pressure roller mechanism; The mixing tank has a closed inner cavity for containing materials; The stirring mechanism includes a main shaft rotatably disposed in the mixing tank, a planetary carrier fixedly mounted on the main shaft, at least one stirring paddle mounted on the planetary carrier for mixing materials, and at least one dispersing component mounted on the planetary carrier for shearing and dispersing materials. The pressure roller mechanism includes at least one pressure roller mounted on the planetary carrier, and the outer peripheral surface of the pressure roller defines a gap between the inner wall surface of the mixing tank for squeezing and shearing the material.

[0006] In an optional embodiment, the stirring mechanism includes two stirring paddles and two dispersing components, and the pressure roller mechanism includes two pressure rollers; The two stirring paddles, the two dispersing components, and the two pressure rollers are arranged at intervals in the circumferential direction of the planetary carrier.

[0007] In an optional embodiment, the stirring mechanism includes a stirring paddle and a dispersing component, and the pressure roller mechanism includes a pressure roller; The stirring paddle, the dispersing component, and the pressure roller are spaced apart in the circumferential direction of the planetary carrier.

[0008] In an optional embodiment, the width of the gap between the outer peripheral surface of the pressure roller and the inner wall surface of the mixing tank is configured to be adjustable between 0.5 mm and 5.0 mm.

[0009] In an optional embodiment, the pressure roller is connected to an independent drive mechanism configured to drive the pressure roller to rotate about its own axis. The rotation direction of the pressure roller is the same as the direction in which the stirring paddle propels the material, and the linear velocity of the pressure roller is greater than the linear velocity of the planetary carrier relative to the inner wall of the mixing tank.

[0010] In an optional embodiment, the outer peripheral surface of the pressure roller is coated with an anti-stick coating.

[0011] In an optional embodiment, the anti-stick coating includes a sandblasted layer; and / or; The anti-stick coating includes a Teflon layer.

[0012] In an optional embodiment, the stirring paddle is a twisted paddle; and / or; The dispersing component is a dispersing disc.

[0013] In an optional embodiment, the stirring paddle is a twisted paddle, and the dispersing component is a dispersing disc; The diameter of the pressure roller is smaller than the diameter of the dispersing disc; The diameter of the pressure roller is 1 / 10 to 1 / 3 of the inner diameter of the mixing tank.

[0014] In a second aspect, the present invention provides a method for preparing a dry electrode slurry for lithium batteries, using the lithium battery dry electrode slurry preparation apparatus as described in any of the foregoing embodiments, comprising the following steps: Active substance powder, conductive agent powder, and binder PTFE powder are added to the mixing tank to form a dry powder mixture; The stirring mechanism is activated to drive the stirring paddle and dispersing component to rotate, thereby performing preliminary stirring and dispersion of the dry powder mixture; The drive mechanism of the pressure roller mechanism is activated to drive at least one pressure roller to rotate about its own axis; Driven by the stirring mechanism, the dry powder mixture is continuously conveyed to the gap between the pressure roller and the inner wall of the mixing tank; As the dry powder mixture passes through the gap, it is subjected to the squeezing and shearing action between the pressure roller and the inner wall of the mixing tank, causing the PTFE binder powder to become fibrous, thereby transforming the dry powder mixture into a bindable dry slurry. By controlling the stirring parameters of the stirring mechanism, the rotation parameters of the pressure roller, and the width of the gap, a dry pulp with a predetermined degree of fiberization can be obtained.

[0015] Compared with the prior art, the technical advantages of the lithium battery dry electrode slurry preparation apparatus and method provided by the present invention are as follows: The present invention provides a lithium battery dry electrode slurry preparation apparatus, comprising: a mixing tank, a stirring mechanism, and a pressure roller mechanism; the mixing tank has a closed inner cavity for containing materials; the stirring mechanism includes a main shaft rotatably disposed in the mixing tank, a planetary carrier fixedly mounted on the main shaft, at least one stirring paddle mounted on the planetary carrier for mixing materials, and at least one dispersion component mounted on the planetary carrier for shearing and dispersing materials; the pressure roller mechanism includes at least one pressure roller mounted on the planetary carrier, and the outer peripheral surface of the pressure roller defines a gap between the inner wall surface of the mixing tank for extruding and shearing the materials.

[0016] By integrating the pressure roller mechanism onto the planetary carrier of the mixing mechanism, the mixing and dispersion of materials and the high-intensity extrusion and shearing process are carried out synchronously in situ within the same device, combining the traditional step-by-step process into one, significantly shortening the process and improving efficiency. At the same time, the gap formed between the pressure roller and the tank wall of the mixing tank constitutes a concentrated and controllable high shear force field, subjecting the material to concentrated extrusion and shearing far exceeding that of traditional mixing when it passes through, thereby achieving more complete and uniform fiberization of the binder. In addition, this integrated design makes the device structure compact, which is very conducive to the continuous and large-scale production of dry electrode slurry.

[0017] The lithium battery dry electrode slurry preparation method provided by the present invention uses the above-mentioned lithium battery dry electrode slurry preparation apparatus. Therefore, the technical advantages and effects achieved by the method include those achieved by the above-mentioned lithium battery dry electrode slurry preparation apparatus, which will not be elaborated here.

[0018] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the lithium battery dry electrode slurry preparation device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram showing the positions of the dispersing disc, the spiral paddle, and the pressure roller on the planetary carrier, as provided in an embodiment of the present invention.

[0021] Icons: 1-Planetary frame; 2-Dispersion disc shaft; 3-Dispersion disc; 4-Twisted paddle; 5-Pressure roller. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] The specific structure is as follows: Figure 1 and Figure 2 As shown.

[0030] This embodiment provides a lithium battery dry electrode slurry preparation apparatus, including: a mixing tank, a stirring mechanism, and a pressure roller 5 mechanism; the mixing tank has a closed inner cavity for containing materials; the stirring mechanism includes a main shaft rotatably disposed in the mixing tank, a planetary carrier 1 fixedly mounted on the main shaft, at least one stirring paddle mounted on the planetary carrier 1 for mixing materials, and at least one dispersion component mounted on the planetary carrier 1 for shearing and dispersing materials; the pressure roller 5 mechanism includes at least one pressure roller 5, the pressure roller 5 is mounted on the planetary carrier 1, and a gap for squeezing and shearing the materials is defined between the outer peripheral surface of the pressure roller 5 and the inner wall surface of the mixing tank.

[0031] In this embodiment, by integrating the pressure roller 5 mechanism onto the planetary carrier 1 of the stirring mechanism, the mixing and dispersion of materials and the high-intensity extrusion and shearing process are carried out synchronously in situ within the same device, combining the traditional step-by-step process into one, significantly shortening the process and improving efficiency. At the same time, the gap formed between the pressure roller 5 and the tank wall of the stirring tank constitutes a concentrated and controllable high shear force field, causing the material to be subjected to concentrated extrusion and shearing far exceeding that of traditional stirring when passing through, thereby achieving more complete and uniform fiberization of the binder. In addition, this integrated design makes the device structure compact, which is very beneficial for the continuous and large-scale production of dry electrode slurry.

[0032] Specifically, the mixing tank is a container with a cylindrical, closed inner cavity. The agitator can be a twisted impeller 4, or other impellers such as a frame impeller or a blade impeller that can achieve macroscopic mixing; the dispersing component can be a dispersing disc 3, or other components such as a toothed disc or a high-speed shear head that can achieve high-shear dispersion. The pressure roller 5 mechanism includes at least one pressure roller 5, which is mounted on the planetary carrier 1, and its outer circumferential surface defines an adjustable gap between it and the inner wall surface of the mixing tank. During operation, the agitation mechanism is responsible for the initial mixing and conveying of the material, while the pressure roller 5 mechanism integrated thereon applies concentrated extrusion and shearing forces to the material passing through the gap, thereby achieving efficient, in-situ fiberization of the binder.

[0033] In this embodiment, the number and arrangement of the stirring paddles, dispersing components, and pressure rollers 5 can be configured as needed. For example, in one embodiment, the stirring mechanism includes two stirring paddles and two dispersing components, and the pressure roller 5 mechanism includes two pressure rollers 5, which are spaced apart in the circumferential direction of the planetary carrier 1. Preferably, the two stirring paddles, the two dispersing components, and the two pressure rollers 5 are symmetrically arranged, resulting in overall force balance. In another embodiment, the stirring mechanism includes one stirring paddle and one dispersing component, and the pressure roller 5 mechanism includes one pressure roller 5, with all three spaced apart in the circumferential direction of the planetary carrier 1. This spacing ensures that the material can be processed uniformly without dead zones.

[0034] In this embodiment, the gap width between the outer peripheral surface of the pressure roller 5 and the inner wall surface of the mixing tank is configured to be adjustable, preferably between 0.5 mm and 5.0 mm. This ensures sufficient shearing force while preventing material blockage.

[0035] In this embodiment, the pressure roller 5 is connected to an independent drive mechanism. This independent drive mechanism not only drives the pressure roller 5 to rotate around its own axis, but is also configured so that the rotation direction of the pressure roller 5 is the same as the direction in which the stirring paddle propels the material, and the linear velocity of the pressure roller 5 is greater than the linear velocity of the planetary carrier 1 relative to the inner wall of the mixing tank. This specific kinematic relationship generates active and enhanced synergistic shearing.

[0036] In this embodiment, the outer peripheral surface of the pressure roller 5 is coated with an anti-stick coating to prevent material adhesion. This anti-stick coating can be a Teflon layer, or a sandblasted layer can be added under the Teflon layer to increase surface roughness and adhesion, or only a sandblasted layer can be provided, as long as the requirements are met.

[0037] In this preferred embodiment, the stirring paddle is specifically a twisted paddle 4, and the dispersing component is specifically a dispersing disc 3, which is mounted on the planetary carrier 1 via a dispersing disc shaft 2. The planetary carrier 1 is driven to rotate by a main shaft, thereby causing the twisted paddle 4 and the dispersing disc 3 to revolve around the axis of the mixing tank. The dispersing disc shaft 2 usually also has a self-rotation drive, so that the dispersing disc 3 rotates at high speed while revolving, achieving strong shearing and dispersing of the material. The pressure roller 5 mechanism includes at least one pressure roller 5, which is mounted on the planetary carrier 1 via a bearing seat. Its rotation axis is parallel to the rotation axis of the planetary carrier 1, and an adjustable gap is formed between the outer circumferential surface of the pressure roller 5 and the inner wall surface of the mixing tank. The pressure roller 5 is connected to an independent drive mechanism, which can control its speed and direction of rotation.

[0038] In this embodiment, in the preferred configuration where the stirring paddle is a twisted paddle 4 and the dispersing component is a dispersing disc 3, the diameter of the pressure roller 5 is further limited to be smaller than the diameter of the dispersing disc 3. Simultaneously, the diameter of the pressure roller 5 is preferably 1 / 10 to 1 / 3 of the inner diameter of the mixing tank. This dimensional design ensures the functionality, structural strength, and compatibility of the pressure roller 5 with the tank body.

[0039] The following are specific implementation methods; Implementation Method 1: In this embodiment, a pair of pressure rollers 5, each with a diameter of 1 / 5 of the inner diameter of the mixing tank, are symmetrically installed on both sides of the planetary carrier 1. The initial gap between the pressure rollers 5 and the inner wall of the mixing tank is set to 2.0 mm. The agitator of the mixing mechanism is a spiral ribbon. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. After entering the fiberization stage, the pressure rollers 5 are activated, so that their rotation direction is the same as the direction in which the agitator pushes the material, and their linear velocity is 1.5 times the velocity of the planetary carrier 1 relative to the inner wall of the mixing tank. As the material is pushed through the gap, the PTFE is subjected to continuous compression and shearing, and fiberization begins.

[0040] Implementation Method 2: In this embodiment, a pair of pressure rollers 5, each with a diameter of 1 / 6 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The initial gap between the pressure rollers 5 and the inner wall of the mixing tank is set to 2.0 mm. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. During the fiberization stage, the pressure rollers 5 are activated, rotating in the same direction as the direction the mixing paddle pushes the material, and their linear velocity is 1.5 times the velocity of the planetary carrier 1 relative to the inner wall.

[0041] Implementation Method 3: In this embodiment, a pair of pressure rollers 5, each with a diameter of 1 / 6 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The gap between the pressure rollers 5 and the inner wall of the mixing tank is adjusted to 1.0 mm. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. During the fiberization stage, the pressure rollers 5 are activated, with their rotation direction aligned with the direction the mixing paddle pushes the material, and their linear velocity being 1.5 times the velocity of the planetary carrier 1 relative to the inner wall.

[0042] Implementation Method 4: In this embodiment, a pair of pressure rollers 5, each with a diameter equal to 1 / 7 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The initial gap between the pressure rollers 5 and the inner wall of the mixing tank is set to 2.0 mm. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. During the fiberization stage, the pressure rollers 5 are activated, rotating in the same direction as the direction the mixing paddle pushes the material, and their linear velocity is 1.5 times the velocity of the planetary carrier 1 relative to the inner wall.

[0043] Implementation Method 5: In this embodiment, a pair of pressure rollers 5, each with a diameter equal to 1 / 8 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The initial gap between the pressure rollers 5 and the inner wall of the mixing tank is set to 2.0 mm. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. During the fiberization stage, the pressure rollers 5 are activated, rotating in the same direction as the direction the mixing paddle pushes the material, and their linear velocity is 1.5 times the velocity of the planetary carrier 1 relative to the inner wall.

[0044] Implementation Method 6: A pair of pressure rollers 5, with a diameter of 1 / 6 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The gap between the pressure rollers 5 and the inner wall of the mixing tank is adjusted and set to 3.0 mm.

[0045] First, dry mixing is performed, during which the pressure roller 5 is not rotating. In the fiberization stage, the pressure roller 5 is started, and its rotation direction is the same as that of the stirring paddle pushing the material, and its linear velocity is 1.5 times the velocity of the planetary carrier 1 relative to the inner wall.

[0046] Implementation Method 7: In this embodiment, a pair of pressure rollers 5, each with a diameter of 1 / 6 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The gap between the pressure rollers 5 and the inner wall of the mixing tank is adjusted to 1.0 mm. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. During the fiberization stage, the pressure rollers 5 are activated, rotating in the same direction as the direction the mixing paddle pushes the material, but with a linear velocity 1.3 times the velocity of the planetary carrier 1 relative to the inner wall.

[0047] Implementation Method 8: In this embodiment, a pair of pressure rollers 5, each with a diameter of 1 / 6 of the inner diameter of the mixing tank, are introduced and symmetrically installed on both sides of the planetary carrier 1. The gap between the pressure rollers 5 and the inner wall of the mixing tank is adjusted to 1.0 mm. Dry mixing is performed first, during which the pressure rollers 5 do not rotate. During the fiberization stage, the pressure rollers 5 are activated, rotating in the same direction as the direction the mixing paddle pushes the material, but with a linear velocity 1.1 times the velocity of the planetary carrier 1 relative to the inner wall.

[0048] In the above embodiments, the stirring paddle refers to the twisted paddle 4, the dispersing component refers to the dispersing disc 3, and the surface of the pressure roller 5 can be coated with Teflon to form a Teflon layer, or it can be sandblasted to form a sandblasted layer, or it can be sandblasted first to form a sandblasted layer, and then coated with Teflon to form a Teflon layer.

[0049] The above embodiments systematically explored the influence of key parameters such as the diameter of the pressure roller 5 (relative to the can diameter), the gap width, and the relative linear velocity between the pressure roller 5 and the planetary carrier 1 on the final fiberization effect, verifying the effectiveness of the device of the present invention in achieving efficient and controllable fiberization through the integrated pressure roller 5 mechanism and the space for parameter optimization.

[0050] This embodiment provides a method for preparing lithium battery dry electrode slurry using the aforementioned lithium battery dry electrode slurry preparation apparatus. Therefore, the technical advantages and effects achieved by this lithium battery dry electrode slurry preparation method include those achieved by the aforementioned lithium battery dry electrode slurry preparation apparatus, which will not be elaborated here.

[0051] The method for preparing dry electrode slurry for lithium batteries includes the following steps: active material powder, conductive agent powder, and binder PTFE powder are added to a mixing tank to form a dry powder mixture; a stirring mechanism is started, driving the stirring paddle and dispersing components to rotate, performing preliminary stirring and dispersion of the dry powder mixture; the drive mechanism of the pressure roller 5 mechanism is started, driving at least one pressure roller 5 to rotate around its own axis; under the drive of the stirring mechanism, the dry powder mixture is continuously conveyed to the gap between the pressure roller 5 and the inner wall of the mixing tank; as the dry powder mixture passes through the gap, it is subjected to the squeezing and shearing action between the pressure roller 5 and the inner wall of the mixing tank, causing the binder PTFE powder to become fibrous, thereby transforming the dry powder mixture into a bindable dry slurry; by controlling the stirring parameters of the stirring mechanism, the rotation parameters of the pressure roller 5, and the width of the gap, a dry slurry with a predetermined degree of fibrosis is obtained.

[0052] Specifically, S1: Active materials, conductive agents, and PTFE binder powder are added to the mixing tank according to a predetermined ratio to form a dry powder mixture. S2: The stirring mechanism is started. The main shaft drives the planetary carrier 1, the spiral paddle 4, and the dispersing disk 3 to rotate together. The spiral paddle 4 performs strong mixing of the dry powder mixture, and the dispersing disk 3 performs preliminary shearing and dispersion. S3: The drive motor of the pressure roller 5 mechanism is started synchronously, driving the two pressure rollers 5 to rotate around their own axes. The rotation direction of the pressure rollers 5 is controlled to be the same as the direction in which the spiral paddle 4 pushes the material, and the linear velocity of the pressure rollers 5 is controlled to be greater than the linear velocity of the planetary carrier 1 relative to the inner wall of the mixing tank. S4: Driven by the stirring mechanism, the dry powder mixture undergoes complex motion inside the tank and is continuously conveyed to the narrow gap between the pressure rollers 5 and the inner wall of the mixing tank. S5: When the dry powder mixture is forced through the gap, it is subjected to huge local extrusion and shearing forces generated between the pressure rollers 5 and the tank wall. Under this concentrated force field, the PTFE binder particles are fully stretched and fibrillated, forming a micro / nanofiber network that wraps around and encapsulates the active material and conductive agent particles. S6: The fibrillation process is precisely controlled by adjusting parameters such as the rotation speed and time of the stirring mechanism, the rotation speed and direction of the pressure roller 5, and the width of the gap. The entire process continues until the dry powder mixture is transformed into a uniform flocculent dry slurry agglomerate with good adhesion and fiber-drawing effect. S7: The material is discharged, and the obtained dry slurry can be directly used in the subsequent roll forming process.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dry electrode slurry preparation apparatus for lithium batteries, characterized in that, include: Mixing tank, mixing mechanism and pressure roller (5) mechanism; The mixing tank has a closed inner cavity for containing materials; The stirring mechanism includes a main shaft rotatably disposed in the mixing tank, a planetary carrier (1) fixedly mounted on the main shaft, at least one stirring paddle mounted on the planetary carrier (1) for mixing materials, and at least one dispersing component mounted on the planetary carrier (1) for shearing and dispersing materials. The pressure roller (5) mechanism includes at least one pressure roller (5), which is mounted on the planetary carrier (1), and the outer peripheral surface of the pressure roller (5) defines a gap between the inner wall surface of the mixing tank for squeezing and shearing the material.

2. The lithium battery dry electrode slurry preparation apparatus according to claim 1, characterized in that, The stirring mechanism includes two stirring paddles and two dispersing components, and the pressure roller (5) mechanism includes two pressure rollers (5). The two stirring paddles, the two dispersing components and the two pressure rollers (5) are arranged at intervals in the circumferential direction of the planetary carrier (1).

3. The lithium battery dry electrode slurry preparation apparatus according to claim 1, characterized in that, The stirring mechanism includes a stirring paddle and a dispersing component, and the pressure roller (5) mechanism includes a pressure roller (5). The stirring paddle, the dispersing component, and the pressure roller (5) are spaced apart in the circumferential direction of the planetary carrier (1).

4. The lithium battery dry electrode slurry preparation apparatus according to claim 1, characterized in that, The width of the gap between the outer peripheral surface of the pressure roller (5) and the inner wall surface of the mixing tank is configured to be adjustable between 0.5 mm and 5.0 mm.

5. The lithium battery dry electrode slurry preparation apparatus according to claim 1, characterized in that, The pressure roller (5) is connected to an independent drive mechanism, which is configured to drive the pressure roller (5) to rotate around its own axis. The rotation direction of the pressure roller (5) is the same as the direction in which the stirring paddle pushes the material to move, and the linear velocity of the pressure roller (5) is greater than the linear velocity of the planetary carrier (1) relative to the inner wall of the mixing tank.

6. The lithium battery dry electrode slurry preparation apparatus according to claim 1, characterized in that, The outer peripheral surface of the pressure roller (5) is coated with an anti-stick coating.

7. The lithium battery dry electrode slurry preparation apparatus according to claim 6, characterized in that, The anti-stick coating includes a sandblasted layer; and / or; The anti-stick coating includes a Teflon layer.

8. The lithium battery dry electrode slurry preparation apparatus according to any one of claims 1-7, characterized in that, The stirring paddle is a twisted paddle (4). and / or; The dispersing component is a dispersing disk (3).

9. The lithium battery dry electrode slurry preparation apparatus according to claim 8, characterized in that, The stirring paddle is a twisted paddle (4), and the dispersing component is a dispersing disc (3). The diameter of the pressure roller (5) is smaller than the diameter of the dispersing disc (3); The diameter of the pressure roller (5) is 1 / 10 to 1 / 3 of the inner diameter of the mixing tank.

10. A method for preparing dry electrode slurry for lithium batteries, characterized in that, Using the lithium battery dry electrode slurry preparation apparatus as described in any one of claims 1 to 9, the method includes the following steps: Active substance powder, conductive agent powder, and binder PTFE powder are added to the mixing tank to form a dry powder mixture; The stirring mechanism is activated to drive the stirring paddle and dispersing component to rotate, thereby performing preliminary stirring and dispersion of the dry powder mixture; The drive mechanism of the pressure roller (5) mechanism is activated to drive the at least one pressure roller (5) to rotate around its own axis; Driven by the stirring mechanism, the dry powder mixture is continuously conveyed to the gap between the pressure roller (5) and the inner wall of the mixing tank; When the dry powder mixture passes through the gap, it is subjected to the squeezing and shearing action between the pressure roller (5) and the inner wall of the mixing tank, causing the PTFE binder powder to become fibrous, thereby transforming the dry powder mixture into a dry slurry with adhesive properties; By controlling the stirring parameters of the stirring mechanism, the rotation parameters of the pressure roller (5), and the width of the gap, a dry pulp with a predetermined degree of fiberization is obtained.

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