Powder processing mechanism and dry mixing method

Abstract

The invention relates to a powder processing mechanism and a dry mixing method. The powder processing mechanism comprises a mixing module, a compaction module, a kneading module, a block breaking module and a shaping module which are sequentially stacked in the vertical direction. The mixing module is used for mixing and dispersing various preset powder materials and outputting primarily mixed first mixed powder; the jolt ramming module is used for mechanically fusing the first mixed powder and outputting uniformly coated second mixed powder; the kneading module is used for kneading and homogenizing the second mixed powder and outputting a third mixed bulk with a three-dimensional fiber network; the block breaking module is used for breaking the third mixed bulk and outputting fourth mixed powder with the particle size of centimeter level and below; and the shaping module is used for shaping the fourth mixed powder and outputting fifth mixed powder with the particle size of millimeter and below. Through multi-module integration, multi-powder continuous mixing dispersion, fusion coating and homogeneous kneading can be realized, the fibrosis degree and uniformity of an adhesive can be accurately regulated and controlled, and the particle size precision can be accurately controlled, so that continuous production is realized.

Description

Technical Field

[0001] This invention relates to the field of powder processing, and in particular to a powder processing mechanism and dry mixing method suitable for secondary batteries. Background Technology

[0002] Dry electrode technology is a novel lithium-ion battery electrode manufacturing technology. It directly forms electrodes from active materials, conductive agents, and binders through physical mixing and mechanical processing, without the use of liquid solvents. It has advantages such as being environmentally friendly and improving electrode compaction density.

[0003] In existing technologies, the dry mixing step is the core process in dry electrode fabrication. It typically relies on multiple specialized devices to sequentially perform mixing and kneading processes, thereby combining the active material, conductive agent, and binder in a specific ratio to form a homogeneous dry powder mixture. However, the traditional dry mixing step, which relies on multiple specialized devices for intermittent production, suffers from the following main problems: (1) The active material, conductive agent, binder and other multi-component materials are prone to agglomeration or uneven distribution during the dry mixing stage, which leads to the imperfect construction of the internal conductive network of the electrode and the decrease in electrode performance (such as conductivity and capacity retention). (2) Traditional equipment is difficult to precisely control the degree of fiberization and uniformity of the adhesive, which can easily lead to failure problems such as electrode powdering and cracking; (3) The connection between each process is not smooth, the production efficiency is low and the batch stability is poor, which cannot meet the needs of large-scale production and the continuous production capacity is weak. (4) The lack of coordination among various special equipment makes it difficult to achieve precise and controllable adjustment of the output particle size in the crushing and shaping process, which affects the consistency of subsequent rolling, sheet making and other processes. Summary of the Invention

[0004] Based on this, it is necessary to address the problems of poor material fiber uniformity, difficulty in accurately controlling the fiber degree and uniformity of binders, insufficient continuous production capacity, and low particle size control precision in the intermittent dry mixing production relying on various special equipment in the existing technology, and to provide a kneading and internal mixer suitable for dry electrode preparation.

[0005] The technical solution adopted in this invention is as follows: The powder processing mechanism includes several modules stacked sequentially and each having different processing components. These modules, arranged along a powder processing path, are a mixing module, a compaction module, a kneading module, a breaking module, and a shaping module. The mixing module is configured to mix and disperse multiple preset powders and output a first mixed powder with preliminary mixing. The compaction module is configured to mechanically fuse the first mixed powder and output a second mixed powder with uniform coating. The kneading module is configured to knead and homogenize the second mixed powder and output a third mixed agglomerate with a three-dimensional fiber network. The breaking module is configured to break the third mixed agglomerate and output a fourth mixed powder with a particle size of centimeters or less. The shaping module is configured to shape the fourth mixed powder and output a fifth mixed powder with a particle size of millimeters or less.

[0006] Several modules are stacked vertically and can be connected in a controlled manner.

[0007] Each module has a feed inlet and a discharge outlet, and the discharge outlet and feed inlet of two adjacent modules are set to overlap accordingly.

[0008] A first valve body that can move horizontally is provided between the mixing module and the compaction module; and / or, a second valve body that can move horizontally is provided between the compaction module and the kneading module; and / or, a third valve body that can move horizontally is provided between the kneading module and the breaking module.

[0009] The mixing module includes a mixing cylinder, a connecting shaft that is vertically and rotatably installed inside the mixing cylinder, and a mixing assembly sleeved on the connecting shaft. The mixing assembly includes dust-raising blades, shearing and dispersing blades, and horn-shaped blades that are axially spaced and staggered.

[0010] The vibration module includes a vibration cylinder, a blade body that is horizontally and rotatably mounted in the vibration cylinder, and a vibration assembly mounted on the blade body. The vibration assembly includes a number of first blade groups and a number of second blade groups that are circumferentially spaced apart, and adjacent first blade groups and second blade groups are axially staggered.

[0011] The kneading module includes a kneading cylinder and a rotor assembly horizontally and rotatably mounted in the kneading cylinder. The rotor assembly includes two parallel kneading rotors, each having a meshing or shearing ridge.

[0012] The fragmentation module includes a fragmentation cylinder, a fragmentation assembly horizontally installed inside the fragmentation cylinder, and a sieve plate located below the fragmentation assembly and having a first particle size control. The fragmentation assembly includes a rotatable rotor disc, several hammers installed on the rotor disc, and several impact plates installed on the inner wall of the fragmentation cylinder and corresponding to the hammers.

[0013] The shaping module includes a shaping cylinder and a shaping assembly vertically mounted inside the shaping cylinder. The shaping assembly includes a rotatable shaping rotor and a shaping stator surrounding the shaping rotor and having a second particle size control.

[0014] A dry mixing method for the aforementioned powder processing mechanism includes the following steps: S1, the preset multi-powder material is mixed and dispersed in the mixing module to obtain the first mixed powder after preliminary mixing, and then falls into the compaction module; S2, the first mixed powder undergoes mechanical fusion in the compaction module to obtain a uniformly coated second mixed powder, which then falls into the kneading module; S3, the second mixed powder is kneaded in the kneading module to obtain a third mixed agglomerate with a three-dimensional fiber network, and then falls into the breaking module; S4, the third mixed agglomerate is broken down in the fragmentation module to obtain the fourth mixed powder with a particle size of centimeters or less, and then falls into the shaping module; S5, the fourth mixed powder is shaped in the shaping module to obtain the fifth mixed powder with a particle size of millimeter or smaller.

[0015] The beneficial effects of this invention are as follows: This invention features a compact and reasonable structure and is easy to operate. By setting up modular components, it can achieve continuous homogeneous dispersion, fusion coating, and strong kneading and mixing of various materials, precisely control the degree of fiberization and uniformity of the binder, and accurately control the particle size accuracy, thereby realizing continuous production and effectively improving the production efficiency and product performance of dry electrode.

[0016] The present invention also has the following advantages: (1) By setting up multi-level blade units and turbulence rods, combined with temperature control jackets, the present invention can realize multi-level shearing of materials inside the mixing cylinder, thereby achieving dispersion of the entire material domain and solving the problem of uneven dispersion of multi-component materials.

[0017] (2) By setting up a blade body, a first blade assembly and a second blade assembly, the high-speed rotation of the blade body generates mechanical force, thereby causing the material particles to be continuously squeezed and impacted between the blade body and the vibrating cylinder, thus achieving mechanical coating and surface modification of multi-component materials.

[0018] (3) By setting two kneading rotors that rotate in opposite directions and at different speeds, combined with an “∞” shaped kneading cylinder, the present invention can achieve continuous kneading of materials, making the binder components more fully and uniformly fibrous and enhancing the kneading effect.

[0019] (4) By setting hammers and impact plates, the present invention can improve the crushing efficiency of the material breaking module, and combine with the screen plate to screen out materials within the target particle size range, thereby achieving preliminary control over the particle size of particulate materials.

[0020] (5) The present invention sets a shaping stator with through holes on the wall and a rotatable shaping rotor. By relying on the centrifugal force and extrusion force generated by the rotation of the shaping rotor, the material inside the shaping cylinder is squeezed out through the through holes, thereby further shaping the granular material through the through holes and achieving precise control of the particle size of the granular material.

[0021] (6) In this invention, the mixing cylinder, vibrating cylinder, kneading cylinder, breaking cylinder and shaping cylinder are seamlessly connected. The material passes through the corresponding modules in sequence to realize continuous production. Compared with traditional intermittent equipment, it can greatly shorten the production cycle, increase production efficiency by 50% and increase production capacity by more than 30%. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention.

[0023] Figure 2 This is a full sectional view of the present invention.

[0024] Figure 3 This is a schematic diagram of the hybrid module in this invention.

[0025] Figure 4 This is a schematic diagram of the vibration module in this invention.

[0026] Figure 5 This is a schematic diagram of the installation structure of the blade body, the first blade assembly, and the second blade assembly in this invention.

[0027] Figure 6 This is a schematic diagram of the kneading module in this invention.

[0028] Figure 7 This is a full sectional view of the kneading module in this invention (valve omitted).

[0029] Figure 8 This is a schematic diagram of the rotor assembly in this invention.

[0030] Figure 9 This is a schematic diagram of the block-breaking module in this invention.

[0031] Figure 10 for Figure 9 The main view.

[0032] Figure 11 This is a schematic diagram of the shaping module in this invention.

[0033] Figure 12 This is a schematic diagram of the modules of the present invention.

[0034] Figure 13 This is a schematic diagram of the preparation process of the present invention.

[0035] Figure 14 This is a schematic diagram of the state of the first mixed powder of the present invention.

[0036] Figure 15 This is a schematic diagram illustrating the state of the second mixed powder of the present invention.

[0037] Figure 16 This is a schematic diagram of the state of the third mixed aggregate of the present invention.

[0038] Figure 17 This is a schematic diagram showing the state of the fourth and fifth mixed powders of the present invention.

[0039] The modules include: 1. Mixing module; 2. Vibration compaction module; 3. Kneading module; 4. Valve; 5. Block breaking module; 6. Shaping module. 100. Mixing chamber; 101. Mixing cylinder; 102. Jacket; 103. Connecting shaft; 104. First blade unit; 105. Second blade unit; 106. Third blade unit; 200. Vibration chamber; 201. Vibration cylinder body; 202. Cutter body; 203. Forward blade; 204. Reverse blade; 300. Kneading chamber; 301. Kneading cylinder body; 302. Rotor assembly; 303. Hydraulic cylinder; 304. Arc plate; 410, 420, 430: Valve body; 411, 421, 423, 431: Sealing part; 412, 422, 424, 432: Opening part; 500. Crushing chamber; 501. Crushing cylinder body; 502. Hammer; 503. Impact plate; 504. Screen plate; 505. Rotor disc; 600, Shaping cavity; 601, Shaping cylinder; 602, Shaping stator; 603, Shaping rotor. Detailed Implementation

[0040] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0041] The structure and function of this invention are as follows: like Figures 12-13 As shown, the powder processing mechanism according to the present invention comprises an assembly of multiple processing modules of different types stacked vertically. The material to be processed enters the processing module located at the top vertically. The material processed in the current processing module is controlled to fall into the next processing module below it for further processing. Finally, the processing module located at the bottom vertically completes the processing and outputs a mixture that meets the requirements.

[0042] Each processing module includes a housing, an inlet and an outlet on the housing, and processing components located within the housing. When both the inlet and outlet on the housing are controlled to close, a closed processing chamber is formed inside the housing. The processing components then process the material entering the processing chamber to prevent leakage of internal dust or intrusion of external contaminants during the processing. The outlet of the upper processing module and the inlet of the lower processing module partially or completely overlap in two adjacent processing modules to prevent leakage during material descent. A valve body is also provided between adjacent processing modules, allowing controlled opening and closing of the adjacent overlapping outlet and inlet to connect the two processing chambers and facilitate material flow and transfer from top to bottom.

[0043] Different types of processing modules can be combinations of two or more of the following: mixing module 1, compaction module 2, kneading module 3, and crushing module. Mixing module 1 is mainly used for mixing and dispersing materials; compaction module 2 is mainly used for mechanically fusing materials; kneading module 3 is mainly used for kneading and homogenizing materials; and crushing module is mainly used for particle size control. The crushing module can also include a fragmentation module 5 and a shaping module 6. Through primary particle size control by fragmentation module 5 and secondary particle size control by shaping module 6, the manufacturing process requirements for higher particle size control can be met. The powder processing mechanism can be an assembly of mixing module 1 + crushing module, kneading module 3 + crushing module, mixing module 1 + kneading module 3 + crushing module, or mixing module 1 + compaction module 2 + kneading module 3 + crushing module. Depending on the specific process requirements of different products, it can complete the integrated preparation of solid materials through multiple processes or steps, including mixing and dispersion, uniform coating, homogenization and kneading, and particle size control, thereby shortening the production line, reducing production equipment, lowering floor space, and reducing energy consumption.

[0044] This invention can be used for the dry preparation of rechargeable lithium batteries, such as the dry preparation of positive electrodes, negative electrodes, or solid electrolytes. The materials used in the dry preparation of electrodes include at least a variety of powders, such as positive or negative electrode active materials, conductive materials, and binder materials. The materials used in the dry preparation of solid electrolytes include at least a variety of powders, such as electrolyte materials and binder materials. The positive electrode active material may include compounds capable of reversibly inserting and deintercalating lithium, such as composite oxides including lithium and selected from cobalt, manganese, nickel, and / or combined metals. The binder may include fibrillable polymers, such as polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, and / or combinations thereof. The conductive material may include carbon-based materials, one or more metal powders or fibers selected from copper, nickel, aluminum, and silver, and / or conductive polymers such as polyphenylene derivatives. The negative electrode active material may include materials capable of reversibly inserting and deintercalating lithium ions, lithium metal, lithium metal alloys, materials capable of doping and dedoping lithium, or transition metal oxides. The electrolyte material may include sulfides, oxides, halides, or polymers.

[0045] The powder processing mechanism conforming to the present invention will be described below using a dry electrode preparation process.

[0046] like Figures 1-11 As shown, a powder processing mechanism suitable for dry electrode preparation includes a modular assembly. The modular assembly is composed of at least two modules selected from a mixing module 1, a compaction module 2, a kneading module 3, a breaking module 5, and a shaping module 6, with each module having a quantity of ≥1. The mixing module 1 stirs multiple materials under a first temperature condition; the compaction module 2 stirs multiple materials under a second temperature condition; the kneading module 3 stirs multiple materials using dual rotors under a third temperature condition; the breaking module 5 stirs multiple materials using a rotor rotating at a target speed under a fourth temperature condition; and the shaping module 6 stirs multiple materials using a stator-rotor assembly. A horizontally movable valve 4 is installed between the mixing module 1 and the compaction module 2, between the compaction module 2 and the kneading module 3, or between the kneading module 3 and the breaking module 5 to control the flow of materials between adjacent modules. The powder processing mechanism in this embodiment uses a mixing module 1 to homogenize and disperse the material, a vibration module 2 to fuse and coat the material, a kneading module 3 with a strong meshing rotor and temperature and pressure control to strongly knead the material, a breaking module 5 to initially break up the material, and a shaping module 6 with a screen to precisely control the particle size. This improves the uniformity of the conductive agent component distribution and the degree of fiberization of the binder component during the dry mixing process, and enables controllable discharge particle size, thereby achieving continuous production. This effectively solves the problems of uneven fiberization and poor production continuity in the dry electrode process, and significantly improves electrode performance and production efficiency.

[0047] In one embodiment of this application, such as Figures 1-2As shown, the powder processing mechanism includes a mixing module 1, a compaction module 2, a kneading module 3, a breaking module 5, and a shaping module 6 arranged vertically from top to bottom. A controllable horizontally movable valve body 410 is installed between the mixing module 1 and the compaction module 2; a controllable horizontally movable valve body 420 is installed between the compaction module 2 and the kneading module 3; and a controllable horizontally movable valve body 430 is installed between the kneading module 3 and the breaking module 5. The valve body 410 has a closed portion 411 and an open portion 412 arranged adjacent to each other along the horizontal movement direction. The closed portion 411 has an upper end face adapted to the shape of the mixing chamber 100 and a lower end face adapted to the shape of the compaction chamber 200, and when the valve body 410 is controlled to be closed, it is located between the discharge port of the mixing module 1 and the inlet of the compaction module 2 to separate the mixing chamber 100 and the compaction chamber 200. The opening 412 has an opening that vertically penetrates the valve body 410 and is located between the discharge port of the mixing module 1 and the inlet of the compaction module 2 when the valve body 410 is controlled to be in the open state, thereby connecting the mixing chamber 100 and the compaction chamber 200. Similarly, the valve body 420 has a closed portion 421 and an opening 422 arranged adjacent to each other in the horizontal movement direction. The closed portion 421 has an upper end face that matches the shape of the compaction chamber 200 and a lower end face that matches the shape of the kneading chamber 300, and is located between the discharge port of the compaction module 2 and the inlet of the kneading module 3 when the valve body 420 is controlled to be in the closed state, thereby separating the compaction chamber 200 and the kneading chamber 300. The opening 422 has an opening that vertically penetrates the valve body 420 and is located between the discharge port of the compaction module 2 and the inlet of the kneading module 3 when the valve body 420 is controlled to be in the open state, thereby connecting the compaction chamber 200 and the kneading chamber 300. Similarly, valve body 430 has a closed portion 431 and an open portion 432 arranged adjacent to each other in the horizontal direction of movement. The closed portion 431 has an upper end face adapted to the shape of the kneading chamber 300 and a lower end face adapted to the shape of the breaking chamber 500, and is located between the outlet of the kneading module 3 and the inlet of the breaking module 5 when the valve body 430 is controlled to be closed, thus separating the kneading chamber 300 and the breaking chamber 500. The open portion 432 has an opening that vertically penetrates the valve body 430, and is located between the outlet of the kneading module 3 and the inlet of the breaking module 5 when the valve body 430 is controlled to be open, thus connecting the kneading chamber 300 and the breaking chamber 500. In other embodiments, valve bodies 410, 420, and 430 may also have different opening and closing methods, such as a rotary feed valve. The opening and closing movements of valve bodies 410, 420, and 430 can be manually, pneumatically, or electrically driven. By rationally setting the powder processing time of each module and controlling the switching timing of valve opening and closing between modules, discontinuous segmented processing can be transformed into continuous integrated powder processing.

[0048] like Figure 3As shown, the structure of the mixing module 1 includes a mixing cylinder 101 with a mixing chamber 100, a connecting shaft 103 vertically installed inside the mixing cylinder 101, and a mixing component sleeved on the connecting shaft 103. The mixing component rotates under the drive of the connecting shaft 103 to mix and disperse various powders entering the mixing chamber 100. In this embodiment, a jacket 102 is fitted to the outside of the mixing cylinder 101. A gap is provided between the inner wall surface of the jacket 102 and the outer wall surface of the mixing cylinder 101, thereby forming a heat exchange space between the jacket 102 and the mixing cylinder 101. A heat exchange medium circulates in the heat exchange space to regulate the temperature inside the mixing cylinder 101.

[0049] In this embodiment, several baffle rods (not shown in the figure) are also installed on the outer circular surface of the connecting shaft 103. The baffle rods rotate with the connecting shaft 103 to stir the material inside the mixing cylinder 101, which can improve the stirring performance of the mixing module 1 and thus enhance the uniformity of the material flow field inside the mixing cylinder 101.

[0050] like Figure 3 As shown, the mixing assembly includes a first blade unit 104, a second blade unit 105, and a third blade unit 106 arranged sequentially and staggered along the connecting shaft 103. The first blade unit 104 includes several horn-shaped blades evenly spaced along the circumference; the second blade unit 105 includes several shearing and dispersing blades evenly spaced along the circumference; and the third blade unit 106 includes several dust-raising blades evenly spaced along the circumference. When the mixing assembly rotates, the dust-raising blades at the bottom lift various powders from the bottom of the mixing chamber 100 upwards, the shearing and dispersing blades in the middle mix and disperse the lifted powders along the circumference, and the horn-shaped blades at the top push the lifted powders in a vortex towards the circumference of the mixing cylinder 101, where the powders exchange heat with the external jacket 102 as they fall along the circumference of the mixing cylinder 101. By setting three layers of blade units, multi-level shearing of multiple powders within the mixing chamber 100 can be achieved, thereby realizing dispersion of the entire material domain. The connecting shaft 103 can be a single-shaft structure or a multi-shaft structure coaxially nested, that is, the first blade unit 104, the second blade unit 105, and the third blade unit 106 have the same or different angular velocities. Preferably, a multi-shaft structure coaxially nested is adopted to better control the mixing and dispersion of powder by each layer of blade units at different linear velocities of 5-60 m / s.

[0051] In this embodiment, the active material, conductive agent, and binder for manufacturing the positive electrode are fed into the mixing cylinder 101 in a ratio of 8:1:1 via a powder metering system. The mixture is then processed in the mixing chamber 100 for 10-60 minutes under conditions where the jacket 102 temperature does not exceed 20°C, the linear velocity of the dust-raising paddle is not less than 20 m / s, and the linear velocity of the shear-dispersing paddle is not less than 30 m / s, to obtain a preliminarily mixed first powder. The valve 410 is opened in a controlled manner to facilitate the transfer of the first mixed powder from the mixing module 1 to the compaction module 2.

[0052] like Figures 4-5 As shown, the structure of the vibration module 2 is as follows: it includes a vibration cylinder 201 with a vibration cavity 200, a rotatable blade 202 horizontally installed inside the vibration cylinder 201, and an array of first blade assemblies and an array of second blade assemblies spaced along the circumference of the outer circumference of the blade 202. Adjacent first blade assemblies and second blade assemblies are arranged axially in a staggered manner. A single set of first blade assemblies includes several forward blades 203 spaced along the axial direction of the blade 202, and a single forward blade 203 is fixed to the blade 202 according to a first rotation direction. A single set of second blade assemblies includes several reverse blades 204 spaced along the axial direction of the blade 202, and a single reverse blade 204 is fixed to the blade 202 according to a second rotation direction. The first rotation direction and the second rotation direction can be the same or opposite. By setting up the blade body 202, the first blade assembly and the second blade assembly, the high-speed rotation of the blade body 202 generates mechanical force, which causes the material particles to be continuously squeezed and impacted between the blade body 202 and the vibrating cylinder 201 or between any adjacent forward blade 203 and reverse blade 204, thereby achieving mechanical coating and surface modification of multi-component materials.

[0053] In this embodiment, the blade body 202 has two sets of first blade assemblies and two sets of second blade assemblies arranged circumferentially. Along the circumferential direction, the two sets of first blade assemblies are spaced 180° apart, and the two sets of second blade assemblies are also spaced 180° apart. Each set of first blade assemblies is spaced 90° apart from its adjacent set of second blade assemblies. The forward blades 203 and reverse blades 204 have identical structures, and adjacent forward blades 203 and reverse blades 204 are arranged at a cross-shaped angle. In another embodiment, the structures of the forward blades 203 and reverse blades 204 may be different. In yet another embodiment, adjacent forward blades 203, adjacent reverse blades 204, and adjacent forward blades 203 and reverse blades 204 have different fixed angles.

[0054] In this embodiment, the first mixed powder transferred from the mixing module 1 to the compaction module 2 is uniformly coated with conductive agent and binder on the surface of the active material by the high-speed rotation (e.g., 1500 r / min) of the blade 202 within the compaction chamber 200. In another embodiment, the temperature within the compaction chamber 200 can be controlled at 40-90℃ to control the degree and rate of binder fibrillation, allowing partial fibrillation of the binder, thus shortening the time required for subsequent binder fibrillation. After being processed by the compaction module 2 for 3-60 minutes, the first mixed powder yields a second mixed powder with a basically uniform coating. The valve 420 is opened in a controlled manner to facilitate the transfer of the second mixed powder from the compaction module 2 to the kneading module 3.

[0055] like Figures 6-7 As shown, the structure of the kneading module 3 is as follows: it includes a kneading cylinder 301 with a kneading cavity 300, and a rotatable rotor assembly 302 horizontally installed inside the kneading cylinder 301. The rotor assembly 302 adopts a low-speed, high-meshing dual-rotor structure. In this embodiment, an arc-shaped plate 304 is installed inside the kneading cylinder 301. The arc-shaped plate 304 is connected to the piston rod of the hydraulic cylinder 303. The piston rod of the hydraulic cylinder 303 extends, thereby driving the arc-shaped plate 304 to move linearly in the horizontal direction, so that the arc-shaped plate 304 approaches the rotor assembly 302 until the gap between the arc-shaped plate 304 and the rotor assembly 302 meets the production requirements. After the arc-shaped plate 304 moves into position, the kneading cavity 300 is in the shape of "∞". The kneading cylinder 301 also has a feeding port parallel to the inlet and close to the arc-shaped plate 304. The feeding port is used to add powder, such as additive powders like diluents and dispersants, or supplementary powders like active materials, conductive agents, and binders, before the second mixed powder begins homogenization and kneading. The valve body 420 also has a closing part 423 and an opening part 424 corresponding to the feeding port. The closing part 423 is adjacent to the opening part 422, and the opening part 424 is adjacent to the closing part 421. When the valve body 420 is moved horizontally in a controlled manner until the opening part 422 is aligned with the inlet of the kneading cylinder 301, the closing part 423 moves simultaneously to align with the feeding port of the kneading cylinder 301 to close the feeding port; and when the valve body 420 is moved horizontally in a controlled manner until the closing part 421 is aligned with the inlet of the kneading cylinder 301, the opening part 424 moves simultaneously to align with the feeding port of the kneading cylinder 301 to open the feeding port. When the feeding port of the kneading cylinder 301 is open, the arc plate 304 is controlled to move away from the rotor assembly 302 to expand the volume of the kneading cavity 300 to facilitate the addition of powder into the kneading cavity 300 through the feeding port; when the feeding port of the kneading cylinder 301 is closed, the arc plate 304 is controlled to move closer to the rotor assembly 302 to form a volume of the kneading cavity 300 suitable for homogenization kneading.

[0056] Rotor assembly 302 includes two meshing or shearing kneading rotors. The gap between the two kneading rotors is 0.2mm-5mm. Within this gap range, rotor assembly 302 can balance shearing force and physical permeability, effectively improving material mixing. The two kneading rotors rotate in opposite directions, but their speeds can be the same or different. The speed ratio of the two kneading rotors is between 1:1 and 1:4. The dual kneading rotors can employ a butterfly-shaped rotating edge (e.g., Figure 8 (as shown), including the same or two different types of meshing or shearing rotating edges such as ∑-type rotating edge, Z-type rotating edge, cutting type rotating edge, and fishtail type rotating edge.

[0057] In this embodiment, the second mixed powder transferred from the compaction module 2 to the kneading module 3 is subjected to a dual kneading rotor with butterfly-shaped rotating edges and a 1mm gap between the edges, rotating at opposite speeds of 20r / min and 30r / min. The temperature within the kneading chamber 300 is controlled to operate at 60℃-110℃ for 0.1h-3h, allowing the binder to fully fibrillate and form a third mixed agglomerate with a three-dimensional fiber network. The valve 430 is opened in a controlled manner to facilitate the transfer of the third mixed agglomerate from the kneading module 3 to the breaking module 5.

[0058] like Figures 9-10 As shown, the structure of the breaking module 5 is as follows: it includes a breaking cylinder 501 with a breaking chamber 500, a rotatable rotor disk 505 horizontally installed inside the breaking cylinder 501, several hammers 502 arranged on the outer wall of the rotor disk 505, and several impact plates 503 arranged on the two opposite walls inside the breaking cylinder 501. Preferably, the inclination angle of the impact plates 503 is 45°. By setting the hammers 502 and the impact plates 503, the breaking efficiency of the breaking module 5 for materials can be improved by the impact of the hammers 502 and the rebound impact of the impact plates 503 on the lumps or agglomerated mixed powders.

[0059] In addition, a sieve plate 504 is installed at the bottom of the crushing cylinder 501, located above the discharge port of the crushing cylinder 501. The sieve plate 504 has a mesh size of 0.5-5cm to screen out powders within the target particle size range (e.g., centimeter size and below). Preferably, the mesh size of the sieve plate 504 is 3cm. To prevent powders of mismatched particle sizes from clogging the sieve plate 504, a rejection device (e.g., pneumatic sorting) corresponding to the sieve plate 504 can also be installed inside the crushing cylinder 501 to remove large-particle-size powders. An opening and closing valve body can be provided between the crushing module 5 and the shaping module 6, or it can be omitted. Preferably, there is no valve body at the discharge port of the crushing cylinder 501.

[0060] In this embodiment, the third mixed agglomerate transferred from the kneading module 3 to the breaking module 5 is subjected to impact from the hammer 502, rebound from the impact plate 503, and screening by the sieve plate 504 at a temperature not exceeding 20°C to obtain a fourth mixed powder with a particle size of centimeters or smaller. The fourth mixed powder is then transferred from the breaking module 5 to the shaping module 6.

[0061] like Figure 11 As shown, the structure of the shaping module 6 includes a shaping cylinder 601 with a shaping cavity 600, a shaping stator 602 vertically installed inside the shaping cylinder 601, and a rotatable shaping rotor 603 corresponding to the shaping stator 602. The shaping stator 602 is funnel-shaped, and through holes are formed on its wall. The diameter of the through holes does not exceed 2 mm. Preferably, the diameter of the through holes is 1 mm. The shaping rotor 603 has a rotating shaft and a rotating arm sleeved on the rotating shaft and close to the shaping stator 602. Preferably, the linear velocity of the rotating arm is 1-60 m / s. By rotating the shaping rotor 603 relative to the shaping stator 602, centrifugal force and extrusion force can be generated, causing the material inside the shaping cylinder 601 to be discharged through the through holes, thereby further shaping the particulate material through the through holes and effectively controlling the particle size of the finished material.

[0062] In this embodiment, the fourth mixed powder transferred from the breaking module 5 to the shaping module 6 is processed by the shaping stator 602 at a controlled rotation speed of 600 r / min by the shaping rotor 603 to obtain a fifth mixed powder of millimeter size and below.

[0063] In this embodiment, the connecting shaft 103 is connected to the output end of the first external rotary drive device, the cutter body 202 is connected to the output end of the second external rotary drive device, the single kneading rotor in the rotor assembly 302 is connected to the output end of the third external rotary drive device, the rotor disk 505 is connected to the output end of the fourth external rotary drive device, and the shaping rotor 603 is connected to the output end of the fifth external rotary drive device. The external rotary drive device can be a servo motor or other drive device capable of outputting torque. The corresponding component connected to its output end is driven to rotate by the external rotary drive device.

[0064] In this embodiment, the powder processing mechanism also includes a control system for controlling the drive devices or valves 4 of each module. The control system can adjust the operation of the drive devices and the opening and closing of the valves 4 according to preset parameters.

[0065] The powder processing unit conveys the fifth mixed powder, which meets the requirements for dry film pressing, to the subsequent processing unit for processing via positive pressure conveying pipeline, negative pressure conveying pipeline, or gravity conveying pipeline. The subsequent processing unit can be a calendering unit composed of several rolling devices that separately produces a self-supporting electrode film, or it can be a continuous rolling dry film forming composite unit composed of several rolling devices and current collector winding and unwinding devices located on the rolling path that directly produces the dry electrode.

[0066] The working process of this invention is as follows: Step 1: Raw material measurement. Measure and take each material component according to the formula ratio. In this embodiment, the ratio of each material component is: active material component: conductive agent component: binder component = 8:1:1.

[0067] Step 2: Shearing and mixing. The measured material components are put into the mixing module 1. Under the first temperature condition, the mixing module 1 stirs the multiple materials to obtain the first electrode mixture that has been initially mixed. Specifically, the first temperature condition is no more than 20°C. The temperature inside the mixing cylinder 101 is controlled to be no more than 20°C by relying on the heat exchange medium. Within this temperature range, the viscosity of various materials inside the mixing cylinder 101 can be precisely controlled to prevent agglomeration. Then, according to the proportions, the measured material components are added into the mixing cylinder 101; The first external rotary drive device connecting shaft 103 rotates, thereby driving the first blade unit 104, the second blade unit 105, the third blade unit 106 and the baffle rod to rotate. The linear velocity of the first blade unit 104, the second blade unit 105 and the third blade unit 106 is required to be 5m / s-60m / s. Within this linear velocity range, the uniform distribution of each material component can be guaranteed. The three-layer impeller unit stirs various materials inside the mixing cylinder 101 for 10-60 minutes, achieving shear mixing of the materials to obtain... Figure 14 The first electrode mixture shown is initially mixed.

[0068] Step 3: High-efficiency vibration compaction. The first electrode mixture enters the vibration compaction module 2. Under the second temperature condition, the vibration compaction module 2 stirs the first electrode mixture, thereby causing the conductive agent or binder component to coat and adsorb onto the active material component. Some of the binder components undergo fibrillation, resulting in a uniformly coated second electrode mixture. Specifically, the second temperature condition is 40℃-90℃, and the temperature inside the vibration compaction cylinder 201 is controlled to be no less than 40℃. In this embodiment, the temperature inside the vibration compaction cylinder 201 is controlled to be within the range of 40℃-90℃. The first electrode mixture enters the vibratory compaction cylinder 201. The second external rotary drive device drives the blade 202 to rotate at a speed of 1500 r / min, thereby driving the first blade assembly and the second blade assembly to rotate, so as to stir the material inside the vibratory compaction cylinder 201 for a stirring time of 3 min-60 min. Under the action of the blade body 202, the first blade assembly, and the second blade assembly, the conductive agent or binder component coats the surface of the active material component, and some of the binder component fibrillates, thereby obtaining... Figure 15 The second electrode mixture is uniformly coated as shown.

[0069] Step 4: Kneading and homogenization. The second electrode mixture enters the kneading module 3. Under the third temperature condition, the kneading module 3 uses dual rotors to stir the second electrode mixture, so that the binder components are completely fibrous, resulting in a homogenized electrode material with a three-dimensional fiber network. Specifically, a third temperature condition (such as 60℃-110℃) is set according to actual production requirements to control the internal temperature of the kneading cylinder 301 to meet the third temperature condition. The second electrode mixture enters the kneading cylinder 301, the piston rod of the hydraulic cylinder 303 extends, driving the arc plate 304 to move in a straight line along the horizontal direction close to the rotor assembly 302. After the arc plate 304 moves into place, the kneading cylinder 301 is in the shape of "∞" with a volume of 50L. Two third external rotary drive devices drive the corresponding kneading rotors to rotate, so as to stir the material inside the kneading cylinder 301. The stirring time is 0.1h-3h, which can meet the requirements of industrial mass production speed (such as 50kg / h). The two kneading rotors rotate in opposite directions, with one rotating at 20 r / min and the other at 30 r / min. The rotor assembly 302 continuously applies strong shearing and strong extrusion to the material inside the kneading cylinder 301, causing the binder to fully fibrose, thereby obtaining... Figure 16 The image shows a homogenized electrode material with a three-dimensional fiber network.

[0070] Step 5: High-efficiency fragmentation and homogenization. The electrode material enters the fragmentation module 5 and, under the fourth temperature condition, the fragmentation module 5 stirs the third mixed agglomerate by means of a rotor rotating at the target speed to achieve material crushing and obtain preliminary crushed particles of centimeter size and below. Specifically, a fourth temperature condition (not exceeding 20°C) is set according to actual production requirements to control the internal temperature of the breaking cylinder 501 to meet the fourth temperature condition. The homogenized electrode material enters the crushing cylinder 501. The fourth external rotary drive device drives the rotor disk 505 to rotate, thereby causing the hammer 502 to rotate relative to the impact plate 503, so as to stir the material inside the crushing cylinder 501. After being impacted by the hammer 502 and bounced by the impact plate 503, the material inside the breaking cylinder 501 is broken into granular material of centimeter size and below. The granular material is screened through a sieve plate 504 (in this embodiment, the sieve plate 504 has a sieve aperture of 3 cm) to separate granular materials within the target particle size range, thereby obtaining the following: Figure 17 The image on the left shows pre-crushed granular materials at the centimeter level and below.

[0071] Step 6: Particle shaping. The initially crushed granular material enters the shaping module 6. Relying on the stator and rotor assembly, the shaping module 6 stirs the various materials to shape them and obtain finished granular materials of millimeter size and below. Specifically, the pre-crushed granular material enters the shaping cylinder 601, and the fifth external rotary drive device drives the shaping rotor 603 to rotate relative to the shaping stator 602 to achieve stirring of the material. The rotational speed of the shaping rotor 603 is 1m / s-60m / s, and the diameter of the through holes opened on the shaping stator 602 is ≤2mm, which is 1mm in this embodiment, to ensure that it matches the particle size requirements of the subsequent rolling process. During the rotation of the shaping rotor 603 relative to the shaping stator 602, the material inside the shaping cylinder 601 is discharged through a perforated screen, achieving precise control of particle size ≤2mm, thereby obtaining... Figure 17 The image on the right shows the finished granular material.

[0072] Step 7: Roll forming. The finished granular material is conveyed to the roll forming device, which rolls the finished granular material into an electrode film of uniform thickness, realizing continuous production.

[0073] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A powder processing mechanism, characterized in that: The system comprises several modules stacked sequentially and each having different processing components. These modules, arranged along a powder processing path, are sequentially a mixing module, a compaction module, a kneading module, a breaking-up module, and a shaping module. The mixing module is configured to mix and disperse multiple preset powders and output a first mixed powder with preliminary mixing. The compaction module is configured to mechanically fuse the first mixed powder and output a second mixed powder with uniform coating. The kneading module is configured to knead and homogenize the second mixed powder and output a third mixed agglomerate with a three-dimensional fiber network. The breaking-up module is configured to break up the third mixed agglomerate and output a fourth mixed powder with a particle size of centimeters or smaller. The shaping module is configured to shape the fourth mixed powder and output a fifth mixed powder with a particle size of millimeters or smaller.

2. The powder processing mechanism as described in claim 1, characterized in that: Several of the modules are stacked sequentially along the vertical direction and can be connected in a controlled manner.

3. The powder processing mechanism as described in claim 1, characterized in that: Each module has a feed inlet and a discharge outlet, and the discharge outlets and feed inlets of two adjacent modules are arranged to overlap.

4. The powder processing mechanism as described in claim 1, characterized in that: A first valve body that can move horizontally is provided between the mixing module and the compaction module; and / or, a second valve body that can move horizontally is provided between the compaction module and the kneading module; and / or, a third valve body that can move horizontally is provided between the kneading module and the breaking module.

5. The powder processing mechanism as described in claim 1, characterized in that: The mixing module includes a mixing cylinder, a connecting shaft vertically and rotatably mounted inside the mixing cylinder, and a mixing component sleeved on the connecting shaft. The mixing component includes dust-raising blades, shearing and dispersing blades, and horn-shaped blades arranged axially at staggered intervals.

6. The powder processing mechanism as described in claim 1, characterized in that: The vibration compaction module includes a vibration compaction cylinder, a blade body that is horizontally and rotatably mounted inside the vibration compaction cylinder, and a vibration compaction assembly mounted on the blade body. The vibration compaction assembly includes a plurality of first blade groups and a plurality of second blade groups spaced circumferentially, with adjacent first blade groups and second blade groups being axially staggered.

7. The powder processing mechanism as described in claim 1, characterized in that: The kneading module includes a kneading cylinder and a rotor assembly horizontally and rotatably mounted in the kneading cylinder. The rotor assembly includes two parallel kneading rotors, each having a meshing or shearing ridge.

8. The powder processing mechanism as described in claim 1, characterized in that: The breaking module includes a breaking cylinder, a breaking assembly horizontally installed inside the breaking cylinder, and a sieve plate located below the breaking assembly and having a first particle size control. The breaking assembly includes a rotatable rotor disc, a plurality of hammers installed on the rotor disc, and a plurality of impact plates installed on the inner wall of the breaking cylinder and corresponding to the hammers.

9. The powder processing mechanism as described in claim 1, characterized in that: The shaping module includes a shaping cylinder and a shaping component vertically installed inside the shaping cylinder. The shaping component includes a rotatable shaping rotor and a shaping stator surrounding the shaping rotor and having a second particle size control.

10. A dry mixing method for use in a powder processing apparatus as described in any one of claims 1-9, characterized in that: Includes the following steps: S1, the preset multi-powder material is mixed and dispersed in the mixing module to obtain the first mixed powder after preliminary mixing, and then falls into the compaction module; S2, the first mixed powder undergoes mechanical fusion in the compaction module to obtain a uniformly coated second mixed powder, which then falls into the kneading module; S3, the second mixed powder is kneaded in the kneading module to obtain a third mixed agglomerate with a three-dimensional fiber network, and then falls into the breaking module; S4, the third mixed agglomerate is broken down in the fragmentation module to obtain the fourth mixed powder with a particle size of centimeters or less, and then falls into the shaping module; S5, the fourth mixed powder is shaped in the shaping module to obtain the fifth mixed powder with a particle size of millimeter or smaller.

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