Efficient fibration unit and material fibration method

Abstract

The invention provides an efficient fibration unit and a material fibration method. The efficient fibration unit comprises a feeding system, a constant-pressure fibration kneading machine and an air-blowing type pelletizer. The kneading machine comprises a heatable chamber, a piston type constant-pressure top cover and a kneading wheel, constant pressure of an inner cavity is ensured by controlling the displacement of the piston top cover, and an electric sliding plate valve is arranged at the bottom of the heatable chamber. The air-blowing type granulator is connected with the kneading machine through a connector and comprises a closed powder collecting barrel and a scraping and screening granulation assembly. The scraping and screening assembly comprises a conical screen, a triangular scraper and a gear motor, the tip of the screen is downwards fixed to the inner wall of the collecting barrel, the scraper is attached to the inner wall of the screen and installed on an output shaft of the motor, and an air guide pipe is arranged in the motor and communicated with an air source. The piston type constant-pressure top cover, the heatable chamber and the electric sliding plate valve are utilized to form the sealed inner cavity of the kneading machine, the piston type constant-pressure top cover is matched to keep the constant pressure of the inner cavity of the kneading machine, the electric sliding plate valve is utilized to realize seamless switching of fibration and granulation procedures, and the continuity of the whole operation is improved.

Description

Technical Field

[0001] The invention relates to the technical field of powder fiberization processing equipment, and in particular to a high-efficiency fiberization unit and a material fiberization method. Background Art

[0002] In the dry electrode film forming process, the fibrillation process of polytetrafluoroethylene (PTFE) is a key technical link that determines the electrode performance. At present, there are three main mainstream methods for PTFE fibrillation: shearing fibrillation through a high-speed mixer, impact fibrillation using a jet mill, and preparation of fibrillated materials using a twin-screw extruder. Although these methods have their own characteristics, they all face some common challenges in practical applications.

[0003] First of all, no matter which process route is used, there is a common problem of open fiberization environment space during its operation, which leads to poor controllability of the entire process and difficulty in ensuring the consistency of the fiber network structure. Specifically: when using a high-speed mixer for shear fiberization, due to the uneven distribution of powder particles in the shear field, it is easy for local areas to coexist with over-shear and under-shear, which directly affects the quality of the final product. Although air flow mill impact fiberization can achieve effective collision and dispersion of powders with the help of high-speed airflow, the instability of the turbulent field makes the degree of fiberization fluctuate greatly, making it difficult to maintain stable product quality. Although twin-screw extrusion mechanical fiberization has the advantage of continuous production, it is difficult to accurately control the global shear strength due to the influence of the complex flow field characteristics in the screw meshing area, which affects the uniformity and effect of fiberization.

[0004] The core problem of the above processes is that they fail to build a stable and precisely controllable fibrillation dynamics environment. As a result, the final powder contains not only short PTFE fibers formed by excessive disentanglement, but also residual agglomerated particles that are not fully fibrillated. This microstructural heterogeneity will directly have an adverse effect on the mechanical strength of the electrode membrane and the consistency of ion transport performance. Summary of the invention

[0005] In view of the problems of low working efficiency, poor continuity, poor sealing and poor particle uniformity of existing fiberizing equipment, the present invention provides a high-efficiency fiberizing unit and a material fiberizing method, which uses a piston-type constant pressure top cover, a heatable chamber and an electric slide valve to form a sealed kneading machine cavity, and cooperates with the piston-type constant pressure top cover to maintain a constant pressure in the kneading machine cavity, thereby ensuring a stable and uniform fiberizing process. At the same time, the electric slide valve is used to achieve seamless switching between the fiberizing and granulating processes, thereby improving the continuity and efficiency of the overall operation.

[0006] The present invention achieves the above technical objectives through the following technical means.

[0007] An efficient fibrillating unit, comprising a feeding system, a constant-pressure fibrillating kneader, and a pneumatic granulator, which are arranged in sequence from top to bottom;

[0008] The constant-pressure fibrillating kneader includes a heatable chamber, a piston-type constant-pressure top cover, and a kneading wheel; the kneading wheel is arranged in the heatable chamber. The upper and lower ends of the heatable chamber are open, and the piston-type constant-pressure top cover is slidably installed in the heatable chamber through the upper opening. An electric slide valve is provided at the lower opening. The piston-type constant-pressure top cover, the heatable chamber, and the electric slide valve form a sealed kneader inner cavity; the upper part of the piston-type constant-pressure top cover is connected to a lifting device, and the constant pressure of the kneader inner cavity is maintained by controlling the up and down displacement of the piston-type constant-pressure top cover;

[0009] The pneumatic granulator is connected to the constant-pressure fibrillating kneader through a connector, and includes a closed powder collection barrel and a scraping and sieving granulation assembly located in the upper part thereof; the upper end of the closed powder collection barrel is open and is butted against the lower opening of the connector; the scraping and sieving granulation assembly includes a conical screen, a triangular scraper, and a reduction motor; the conical screen is fixed on the inner wall of the closed powder collection barrel with the tip facing downwards, the triangular scraper is installed on the output shaft of the reduction motor and is located above the conical screen, and is attached to the inner wall of the conical screen; an air duct communicating with the air source is provided inside the reduction motor.

[0010] Further, the kneading wheel includes a first kneading wheel and a second kneading wheel arranged in parallel. The shaft of the first kneading wheel is the driving shaft, and male-type blades are assembled thereon; the second kneading wheel is the driven wheel, and is driven by a gear set with the driving wheel, and female-type blades are assembled thereon for rotation; the male-type blades and the female-type blades rotate relatively, and the minimum gap between the male-type blades and the female-type blades is 0.1 - 1 mm, and the rotational speed of the male-type blades is 1.5 - 3 times that of the female-type blades.

[0011] Further, the cross-section of the male-type blade is in the shape of a blade. Taking the axis of the male-type blade as the coordinate origin O, the line connecting the origin O and the right endpoint of the male-type blade is the X-axis, and the upper half edge line L1 is an arc structure: setting the distance from the origin O to the right endpoint as s, the circular arc center coordinates of the edge line L1 are (a1, b1), satisfying 0.5s < a1 < 0.75s and -0.25s < b1 < -0.1s, and the circular arc radius R1 of the edge line L1 satisfies 0.4s < R1 < 0.7s;

[0012] The lower half edge line L2 is a sine curve: y2 = a2·sin(b2x - c2), where 0.2s < a2 < 0.4s, b2 < 1, c2 > 1;

[0013] The radius R of the middle shaft of the male-type blade g is 0.2s < R g < 0.5s.

[0014] Further, the cross-section of the mother blade is sickle-shaped. Taking the axis of the mother blade as the coordinate origin O, the line connecting the origin O and the right endpoint of the mother blade as the X-axis, and the edge line L3 of its upper half is a downward convex arc: Let the distance from the origin O to the right endpoint be s, the circular arc center coordinates of the edge line L3 be (a3, b3), satisfying 0.5s < a3 < 0.8s and 0.25s < b3 < 0.5s, and the radius R3 of the edge line L3 satisfies 0.4s < R3 < 0.7s;

[0015] The edge line of the lower half is composed of two circular arcs: The left edge line L4 is an upward convex arc, the circular arc center coordinates of the edge line L4 are (a4, b4), satisfying 0.2s < a4 < 0.4s and -0.7s < b4 < -0.4s, and the radius R4 satisfies 0.2s < R4 < 0.5s; The right edge line L5 is a downward concave arc, the circular arc center coordinates are (a5, b5), satisfying 0.4s < a5 < 0.8s and 0.05s < b5 < 0.2s, and the radius R5 satisfies 0.2s < R5 < 0.5s;

[0016] The radius of the middle axis of the mother blade is R m is 0.2s < R m <0.5s.

[0017] Further, the electric slide valve includes a valve body, a slide plate and an electric actuator; the valve body is installed at the lower opening of the heatable chamber, the slide plate is slidably installed on the valve body and driven by the electric actuator to make reciprocating movements; a metal sealing surface is adopted between the slide plate and the valve body, with Ra ≤ 0.8μm, and a fluororubber elastic gasket is provided between the slide plate and the valve body;

[0018] The upper end surface of the slide plate is in a "ω" shape and matches the rotation trajectories of the male blade and the mother blade. The minimum clearance between the male blade, the mother blade and the heatable chamber and the slide plate is 0.1 - 1 mm; the heating temperature of the heatable chamber is 30°C - 200°C;

[0019] Preferably, the upper end of the connector is square, with the same shape as the lower opening of the heatable chamber, and the lower end is circular, adapted to the upper opening size of the closed powder collection barrel.

[0020] Further, the aperture of the conical screen is 0.1 - 2 mm, and the speed ratio of the triangular scraper to the reduction motor is 1:(1.2 - 1.5).

[0021] Further, the feeding system includes a conical mixer and a pneumatic feeding valve, and the material in the conical mixer is controlled by the pneumatic feeding valve to be added to the constant-pressure fiberization kneader.

[0022] Further, a control system is also included, and the control system includes:

[0023] A pressure sensor installed in the inner cavity of the kneading machine is used to detect the inner cavity pressure value of the kneading machine in real time;

[0024] A detection device for detecting the current or torque of the kneading wheel driving shaft driving device, wherein the detection device is an ammeter or a torque sensor;

[0025] And a controller is used to collect the pressure value of the inner cavity of the kneading machine and the working driving force of the kneading wheel driving shaft, and control the opening and closing of the pneumatic feeding valve and the electric sliding plate valve, as well as the lifting and lowering of the piston-type constant pressure top cover.

[0026] The material fiberization method based on the high-efficiency fiberization unit includes kneading fiberization treatment and scraping and screening treatment; the steps of the kneading fiberization treatment are as follows:

[0027] Before starting the kneading fiberization process, first ensure that the electric slide valve is in a closed state, then the controller controls the lifting and lowering of the piston-type constant pressure top cover to maintain the constant pressure of the kneading machine cavity, and then the controller controls the material in the conical mixer to be added to the constant pressure fiberization kneading machine through the pneumatic feeding valve, and starts the kneading wheel to start the kneading fiberization process; the material comprises a main powder and a fiberizable polytetrafluoroethylene (PTFE) powder, wherein the main powder is selected from at least one of a battery positive / negative electrode material mixture, polyphenylene sulfide powder or a solid electrolyte powder;

[0028] During the kneading and fiberizing process, the detection device monitors and detects the current or torque of the kneading wheel driving shaft driving device in real time and sends it to the controller; the controller opens the electric slide valve according to the working driving force of the kneading wheel driving shaft, pours the powder in the kneading machine cavity into the conical screen below, and then closes the electric slide valve, and the kneading and fiberizing process is completed;

[0029] The steps of the scraping and screening process are as follows:

[0030] After the electric slide valve is opened, the controller starts the reduction motor and drives the triangular scraper to rotate along the inner wall of the conical screen. At the same time, the controller turns on the air source and sprays high-pressure gas through the air duct. The powder that falls into the conical screen is completely crushed and sieved and falls into the bottom of the closed powder collection bucket. The controller turns off the reduction motor and air source, and the scraping and screening process is completed.

[0031] Furthermore, the adjustment range of the inner cavity pressure of the kneading machine is 0.1-3 MPa, the rotation speed of the triangular scraper is 2000 rpm-3000 rpm, and the pressure of the high-pressure gas is 0.05-0.3 MPa.

[0032] The beneficial effects of the present invention are as follows:

[0033] 1. The present invention uses a piston-type constant pressure top cover, a heatable chamber, and an electric slide valve to form a sealed kneading machine cavity, and cooperates with the piston-type constant pressure top cover to maintain a constant pressure in the kneading machine cavity, effectively avoiding the fiber breakage or agglomeration problem caused by pressure fluctuations, thereby significantly improving the uniformity of fiberization and the strength of the finished product. In addition, the present invention further ensures that the fiberization process is stable and uniform through constant temperature control technology.

[0034] 2. The present invention adopts blade-shaped male blades and sickle-shaped female blades, which rotate at a speed difference of 1.5 to 3 times. The fiber disentanglement is accelerated through the synergistic effect of strong shearing and stretching, which greatly improves the fiberization efficiency and reduces energy consumption. The present invention achieves uniform coverage and dead-angle processing of powder materials through the precise design of the blade gap and the optimization of size parameters, and strictly controls the fiber diameter deviation within 5%.

[0035] 3. The application of the electric slide valve in the present invention realizes seamless feeding. With the integrated screening-granulation process, the idling time of the equipment is reduced by 90% and the production capacity is increased by 30%. In addition, the electric slide valve adopts a double sealing mechanism of metal hard sealing surface and fluororubber elastic gasket, and combined with the closed powder collection bucket, the dust emission is reduced to 1mg / m 3 The following meets the standard requirements of clean workshops.

[0036] 4. The present invention collects the working driving force of the kneading wheel driving shaft to determine the end point of fiberization in real time, thereby avoiding the errors that may be caused by relying on manual experience and improving the automation level of the entire device.

[0037] 5. The present invention can not only effectively prevent powder from penetrating into the mechanical gap of the reduction motor and ensure the smooth operation of the equipment by spraying high-pressure gas while scraping the screen, but also cooperate with the conical screen and the triangular scraper to improve the uniformity of the screened particles to 98%, and the screening efficiency is increased to more than 95%, so that it can meet the process requirements of subsequent roller pressing and film forming.

[0038] 6. The high-efficiency fiberizing unit of the present invention is suitable for the processing of various high-value-added powders such as battery positive / negative electrode materials, polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE) and solid electrolytes, and can meet the requirement of aspect ratio ≥100:1, and can meet the rolling process requirements of ultra-thin electrodes with a thickness of less than 5 μm. The constant pressure fiberizing kneader and granulator can operate independently or in series, and are suitable for multiple scenarios from laboratory tests with 5L chambers to industrial mass production with 2000L chambers, demonstrating strong adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a front cross-sectional view of the high-efficiency fiberizing unit of the present invention.

[0040] Figure 2 It is a side sectional view of the high-efficiency fiberizing unit of the present invention.

[0041] Figure 3 This is a schematic diagram of the structure of a male blade.

[0042] Figure 4 This is a schematic diagram of the structure of the mother blade.

[0043] Figure 5 It is a structural schematic diagram of the electric slide valve.

[0044] Figure 6 It is a front cross-sectional view of the high-efficiency fiberizing unit showing the material block crushing and screening status after fiberization.

[0045] Figure 7 It is a side cross-sectional view of the high-efficiency fiberizing unit showing the material block crushing and screening status after fiberization.

[0046] The reference numerals are as follows:

[0047] 1-conical mixer; 2-pneumatic feed valve; 3-heatable chamber; 4-piston constant pressure top cover; 5-electric slide valve; 6-male paddle; 7-female paddle; 8-enclosed powder collection bucket; 9-connector; 10-conical screen; 11-triangular scraper; 12-reduction motor. DETAILED DESCRIPTION

[0048] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

[0049] Example 1

[0050] The high-efficiency fiberizing unit described in this embodiment includes a feeding system, a constant-pressure fiberizing kneading machine, an air-blowing granulator, and a control system, which are arranged in sequence from top to bottom. Figure 1 , 2 They are respectively a front sectional view and a side sectional view of the high-efficiency fiberizing unit described in this embodiment.

[0051] The feeding system includes a conical mixer 1 and a pneumatic feeding valve 2, and the pneumatic feeding valve 2 controls the material in the conical mixer 1 to be added to the constant pressure fiberizing kneading machine. The material placed in the conical mixer 1 includes a main powder and a fiberizable polytetrafluoroethylene (PTFE) powder, wherein the main powder is selected from at least one of a battery positive / negative electrode material mixture, polyphenylene sulfide powder or a solid electrolyte powder.

[0052] The constant-pressure fibrillating kneader includes a heatable chamber 3, a piston-type constant-pressure top cover 4, and kneading wheels. The kneading wheels are arranged in the heatable chamber 3 and include a first kneading wheel and a second kneading wheel arranged in parallel. The shaft of the first kneading wheel is the driving shaft, on which a male-type paddle 6 is assembled. The second kneading wheel is a driven wheel and is driven by a gear set with the driving wheel. A female-type paddle 7 is rotatably assembled thereon. The male-type paddle 6 and the female-type paddle 7 rotate relatively, and the minimum gap between the male-type paddle 6 and the female-type paddle 7 is 0.3 mm. The rotational speed of the male-type paddle 6 is twice that of the female-type paddle.

[0053] The cross-section of the male-type paddle 6 is blade-shaped. Taking the axis center of the male-type paddle 6 as the coordinate origin O, the line connecting the origin O and the right endpoint of the male-type paddle 6 is the X-axis. The upper half edge line L1 is an arc structure: setting the distance from the origin O to the right endpoint as s, the circular arc center coordinates of the edge line L1 are (a1, b1), satisfying 0.5s < a1 < 0.75s and -0.25s < b1 < -0.1s, and the circular arc radius R1 of the edge line L1 satisfies 0.4s < R1 < 0.7s. The lower half edge line L2 is a sine curve: y2 = a2·sin(b2x - c2), where 0.2x < a2 < 0.4x, b2 < 1, c2 > 1, and the radius R of the middle axis of the male-type paddle 6 g satisfies 0.2s < R g < 0.5s, Figure 3 is the structural schematic diagram of the male-type paddle described in this embodiment.

[0054] The cross-section of the female-type paddle 7 is sickle-shaped. Taking the axis center of the female-type paddle 7 as the coordinate origin O, the line connecting the origin O and the right endpoint of the female-type paddle 7 is the X-axis. The upper half edge line L3 is a downward convex arc shape: setting the distance from the origin O to the right endpoint as s, the circular arc center coordinates of the edge line L3 are (a3, b3), satisfying 0.5s < a3 < 0.8s and 0.25s < b3 < 0.5s, and the radius R3 of the edge line L3 satisfies 0.4s < R3 < 0.7s.

[0055] The lower half edge line is composed of two arcs: the left edge line L4 is an upward convex arc, and the circular arc center coordinates of the edge line L4 are (a4, b4), satisfying 0.2s < a4 < 0.4s and -0.7s < b4 < -0.4s, and the radius R4 satisfies 0.2s < R4 < 0.5s; the right edge line L5 is a downward concave arc, and the circular arc center coordinates are (a5, b5), satisfying 0.4s < a5 < 0.8s and 0.05s < b5 < 0.2s, and the radius R5 satisfies 0.2s < R5 < 0.5s, and the radius R of the middle axis of the female-type paddle 7 m satisfies 0.2s < R m < 0.5s, Figure 4 is the structural schematic diagram of the female-type paddle described in this embodiment.

[0056] The upper and lower ends of the heatable chamber 3 are open, the heating temperature of the heatable chamber 3 is 80°C, and the piston-type constant pressure top cover 4 is slidably installed in the heatable chamber 3 through the upper end opening, and an electric slide valve 5 is provided at the lower end opening. The electric slide valve 5 includes a valve body, a slide plate and an electric actuator. Figure 5 It is a schematic diagram of the structure of the electric slide valve. The valve body is installed at the lower end opening of the heatable chamber 3, and the slide is slidably installed on the valve body and driven by the electric actuator to reciprocate. A metal sealing surface is used between the slide and the valve body, and its Ra≤0.8μm, and a fluororubber elastic gasket is provided between the slide and the valve body. The upper end surface of the slide is in the shape of "ω" and matches the rotation trajectory of the male blade 6 and the female blade 7. The minimum gap between the male blade 6, the female blade 7 and the heatable chamber 3 and the slide is 0.1-1mm. The piston-type constant pressure top cover 4, the heatable chamber 3, and the electric slide valve 5 form a sealed kneading machine cavity. The upper part of the piston-type constant pressure top cover 4 is connected to the lifting device, and the constant pressure of 0.3MPa in the kneading machine cavity is maintained by controlling the up and down displacement of the piston-type constant pressure top cover 4.

[0057] The air-blowing granulator is connected to the constant pressure fiberizing kneading machine through a connector 9. The upper end of the connector 9 is square, which is the same shape as the lower end opening of the heatable chamber 3, and the lower end is round, which is adapted to the size of the upper end opening of the closed powder collecting barrel 8. The air-blowing granulator includes a closed powder collecting barrel 8 and a scraping and screening granulation assembly located in the upper part thereof. The upper end of the closed powder collecting barrel 8 is open and docked with the lower end opening of the connector 9; the scraping and screening granulation assembly includes a conical screen 10, a triangular scraper 11 and a reduction motor 12. The conical screen 10 is fixed on the inner wall of the closed powder collecting barrel 8 with the tip facing downward, and the aperture of the conical screen 10 is 1 mm. The triangular scraper 11 is mounted on the output shaft of the reduction motor 12, the speed ratio of the triangular scraper 11 to the reduction motor 12 is 1:1.3, and is located above the conical screen 10, and fits the inner wall of the conical screen 10, and the speed of the triangular scraper 11 is 2000rmp. An air duct connected to the air source is provided inside the reducer 12, and the pressure of the output high-pressure gas is 0.1MPa.

[0058] The control system includes: a pressure sensor installed in the inner cavity of the kneading machine, which is used to detect the inner cavity pressure value of the kneading machine in real time; a detection device for detecting the current or torque of the kneading wheel driving shaft driving device, and the detection device is an ammeter or a torque sensor; and a controller, which is used to collect the inner cavity pressure value of the kneading machine and the working driving force of the kneading wheel driving shaft, and control the opening and closing of the pneumatic feed valve 2 and the electric slide valve 5, and the lifting and lowering of the piston-type constant pressure top cover 4.

[0059] The material fiberization method using the above-mentioned high-efficiency fiberization unit includes kneading fiberization treatment and scraping and screening treatment, and the steps of the kneading fiberization treatment are as follows:

[0060] Before starting the kneading fiberization process, first ensure that the electric slide valve 5 is in a closed state, then the controller controls the lifting and lowering of the piston-type constant pressure top cover 4 to maintain the constant pressure in the kneading machine cavity, and then the controller controls the material in the conical mixer 1 to be added to the constant pressure fiberization kneading machine through the pneumatic feeding valve 2, and starts the kneading wheel to start the kneading fiberization process. The material includes graphite and fiberized polytetrafluoroethylene powder.

[0061] During the kneading and fiberizing process, the detection device monitors the current or torque of the kneading wheel driving shaft driving device in real time and sends it to the controller; the controller opens the electric slide valve 5 according to the working driving force of the kneading wheel driving shaft, pours the powder in the inner cavity of the kneading machine into the conical screen 10 below, and then closes the electric slide valve 5, and the kneading and fiberizing process is completed.

[0062] The steps of the scraping and screening process are as follows:

[0063] After the electric slide valve 5 is opened, the controller starts the reduction motor 12, drives the triangular scraper 11 to rotate along the inner wall of the conical screen 10, and at the same time, the controller turns on the air source to spray high-pressure gas through the air duct. The powder that falls into the conical screen 10 is completely crushed and sieved and falls into the bottom of the closed powder collecting barrel 8. The controller turns off the reduction motor 12 and the air source, and the scraping and screening process is completed. Figure 6 , 7 They are the front sectional view and side sectional view of the high-efficiency fiberizing unit showing the material block crushing and screening status after fiberization.

[0064] The particles after scraping and screening are collected and rolled into a film, with PTFE ≤ 1% and a tensile strength ≥ 5Mpa.

[0065] Example 2

[0066] The difference between this embodiment and Example 1 is that the ternary 811 positive electrode powder, Super-P, CNT and PTFE are placed in the conical mixer 1 in a mass ratio of 96.5:1:0.5:2, the pressure in the kneading machine cavity is maintained at 0.8MPa, the aperture of the conical screen 10 is 300-500μm, and the other structures and methods remain unchanged.

[0067] The particles after the scraping and screening process in this embodiment are collected and rolled into a film, and the tensile strength thereof is ≥4 MPa.

[0068] Example 3

[0069] The difference between this embodiment and embodiment 1 is that polyphenylene sulfide powder and PTFE are placed in the mixer 1 at a mass ratio of 94:6, the pressure in the kneader cavity is maintained at 0.6 MPa, the aperture of the conical screen 10 is 2 mm, and the rest of the structure and method remain unchanged.

[0070] The particles after the scraping and screening treatment in this embodiment are collected and rolled into a film, with a porosity of ≤3% and a tensile strength of ≥2MPa.

[0071] The embodiments are preferred implementations of the present invention, but the present invention is not limited to the above-mentioned implementations. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essential content of the present invention belong to the protection scope of the present invention.

Claims

1. A high-efficiency fiberizing unit, characterized in that: It includes a feeding system, a constant-pressure fibrillating kneader, and a pneumatic pelletizer arranged in sequence from top to bottom; The constant-pressure fibrillating kneader includes a heatable chamber (3), a piston-type constant-pressure top cover (4), and kneading wheels; the kneading wheels are arranged in the heatable chamber (3). The upper and lower ends of the heatable chamber (3) are open, and the piston-type constant-pressure top cover (4) is slidably installed in the heatable chamber (3) through the upper opening. An electric slide valve (5) is provided at the lower opening. The piston-type constant-pressure top cover (4), the heatable chamber (3), and the electric slide valve (5) form a sealed kneader inner cavity; the upper part of the piston-type constant-pressure top cover (4) is connected to a lifting device, and the constant pressure of the kneader inner cavity is maintained by controlling the up and down displacement of the piston-type constant-pressure top cover (4); The pneumatic pelletizer is connected to the constant-pressure fibrillating kneader through a connector (9), and includes a closed powder collection barrel (8) and a scraping and sieving pelletizing assembly located in its upper part; the upper end of the closed powder collection barrel (8) is open and is对接 with the lower opening of the connector (9); the scraping and sieving pelletizing assembly includes a conical sieve mesh (10), a triangular scraper (11), and a reduction motor (12); the conical sieve mesh (10) is fixed on the inner wall of the closed powder collection barrel (8) with its tip facing downwards, the triangular scraper (11) is installed on the output shaft of the reduction motor (12) and is located above the conical sieve mesh (10) and fits the inner wall of the conical sieve mesh (10); an air duct communicating with the air source is provided inside the reduction motor (12).

2. The high-efficiency fiberizing unit according to claim 1, characterized in that: The kneading wheels include a first kneading wheel and a second kneading wheel arranged in parallel. The shaft of the first kneading wheel is the driving shaft, and a male-type paddle (6) is assembled thereon; the second kneading wheel is the driven wheel and is driven by a gear set with the driving wheel, and a female-type paddle (7) is rotatably assembled thereon; the male-type paddle (6) and the female-type paddle (7) rotate relatively, and the minimum gap between the male-type paddle (6) and the female-type paddle (7) is 0.1 - 1 mm, and the rotational speed of the male-type paddle (6) is 1.5 - 3 times that of the female-type paddle.

3. The high-efficiency fiberizing unit according to claim 1, characterized in that: The cross-section of the male-type paddle (6) is blade-shaped. Taking the axis of the male-type paddle (6) as the coordinate origin O, the line connecting the origin O and the right endpoint of the male-type paddle (6) is the X-axis, and the upper half-edge line L1 is an arc structure: setting the distance from the origin O to the right endpoint as s, the circular arc center coordinates of the edge line L1 are (a1, b1), satisfying 0.5s < a1 < 0.75s and -0.25s < b1 < -0.1s, and the circular arc radius R1 of the edge line L1 satisfies 0.4s < R1 < 0.7s; The lower half-edge line L2 is a sine curve: y2 = a2·sin(b2x - c2), where 0.2s < a2 < 0.4s, b2 < 1, c2 > 1; Radius R of the intermediate shaft of the male blade (6) g 0.2s <R g <0.5s.

4. The high-efficiency fiberizing unit according to claim 1, characterized in that: The cross-section of the mother blade (7) is sickle-shaped. Taking the axis of the mother blade (7) as the coordinate origin O, the line connecting the origin O and the right endpoint of the mother blade (7) is the X-axis, and the upper half of its edge line L3 is a downward convex circular arc: Let the distance from the origin O to the right endpoint be s, the circular arc center coordinates of the edge line L3 be (a3, b3), satisfying 0.5s < a3 < 0.8s and 0.25s < b3 < 0.5s, and the radius R3 of the edge line L3 satisfies 0.4s < R3 < 0.7s; The lower half of the edge line consists of two circular arcs: The left edge line L4 is an upward convex circular arc, and the circular arc center coordinates of the edge line L4 are (a4, b4), satisfying 0.2s < a4 < 0.4s and -0.7s < b4 < -0.4s, and the radius R4 satisfies 0.2s < R4 < 0.5s; The right edge line L5 is a downward concave circular arc, and the circular arc center coordinates are (a5, b5), satisfying 0.4s < a5 < 0.8s and 0.05s < b5 < 0.2s, and the radius R5 satisfies 0.2s < R5 < 0.5s; The radius of the intermediate axis of the female blade (7) is R m 0.2s <R m <0.5s.

5. The high-efficiency fiberizing unit according to claim 1, characterized in that: The electric slide valve (5) includes a valve body, a slide plate, and an electric actuator; The valve body is installed at the lower end opening of the heatable chamber (3), the slide plate is slidably installed on the valve body, and is driven by the electric actuator to perform a horizontal reciprocating motion; A metal sealing surface is adopted between the slide plate and the valve body, with Ra ≤ 0.8 μm, and a fluororubber elastic gasket is provided between the slide plate and the valve body; The upper end surface of the slide plate is in a "ω" shape and matches the rotation trajectories of the male blade (6) and the mother blade (7). The minimum clearance between the male blade (6), the mother blade (7) and the heatable chamber (3), the slide plate is 0.1 - 1 mm; The heating temperature of the heatable chamber (3) is 30°C - 200°C; Preferably, the upper end of the connector (9) is square, with the same shape as the lower end opening of the heatable chamber (3), and the lower end is circular, adapted to the upper end opening size of the closed powder collection barrel (8).

6. The high-efficiency fiberizing unit according to claim 1, characterized in that: The aperture of the conical screen (10) is 0.1 - 2 mm, and the speed ratio of the triangular scraper (11) to the reduction motor (12) is 1:(1.2 - 1.5).

7. The high-efficiency fiberizing unit according to claim 1, characterized in that: The feeding system includes a conical mixer (1) and a pneumatic feeding valve (2), and the pneumatic feeding valve (2) is used to control the addition of the material in the conical mixer (1) to the constant-pressure fiberization kneader.

8. The high-efficiency fiberizing unit according to claim 1, characterized in that: It also includes a control system, and the control system includes: A pressure sensor installed in the inner cavity of the kneader, used to detect the inner cavity pressure value of the kneader in real time; A detection device for detecting the current or torque of the driving device of the kneading wheel main shaft; The detection device is an ammeter or a torque sensor; And a controller, used to collect the inner cavity pressure value of the kneader and the working driving force of the kneading wheel main shaft, and control the opening and closing of the pneumatic feeding valve (2) and the electric slide valve (5), as well as the lifting of the piston-type constant-pressure top cover (4).

9. A material fiberizing method based on the high-efficiency fiberizing unit according to any one of claims 1 to 8, characterized in that: It includes kneading and fiberization treatment and scraping and screening treatment; The steps of the kneading and fiberization treatment are as follows: Before starting the kneading fiberization process, first ensure that the electric slide valve (5) is in a closed state, then the controller controls the lifting and lowering of the piston-type constant pressure top cover (4) to maintain the constant pressure of the kneading machine inner cavity, and then the controller controls the material in the conical mixer (1) to be added to the constant pressure fiberization kneading machine through the pneumatic feed valve (2), and starts the kneading wheel to start the kneading fiberization process; the material comprises a main powder and a fiberizable polytetrafluoroethylene (PTFE) powder, wherein the main powder is selected from at least one of a battery positive / negative electrode material mixture, polyphenylene sulfide powder or solid electrolyte powder; During the kneading and fiberizing process, the detection device monitors the current or torque of the kneading wheel driving shaft driving device in real time and sends it to the controller; the controller opens the electric slide valve (5) according to the working driving force of the kneading wheel driving shaft, pours the powder in the kneading machine cavity into the conical screen (10) below, and then closes the electric slide valve (5), and the kneading and fiberizing process is completed; The steps of the scraping and screening process are as follows: After the electric slide valve (5) is opened, the controller starts the reduction motor (12) to drive the triangular scraper (11) to rotate along the inner wall of the conical screen (10). At the same time, the controller turns on the air source to spray high-pressure gas through the air duct. The powder falling into the conical screen (10) is completely crushed and sieved and falls into the bottom of the closed powder collection bucket (8). The controller then turns off the reduction motor (12) and the air source, and the scraping and sieving process is completed.

10. The material fiberization method according to claim 9, characterized in that: The adjustment range of the inner cavity pressure of the kneading machine is 0.1-3 MPa, the rotation speed of the triangular scraper (11) is 2000-3000 rpm, and the pressure of the high-pressure gas is 0.05-0.3 MPa.

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