Mixer and method for dry electrode

Abstract

The invention relates to the technical field of battery production, and provides a mixer and method for a dry electrode, the mixer comprises a first mixing mechanism, a fibration mechanism and a second mixing mechanism, the first mixing mechanism is used for premixing an electrode material and a conductive agent; the fibration mechanism is used for fibration of a binder; and the second mixing mechanism is used for compounding a mixture obtained by premixing the electrode material and the conductive agent with the fiberized binder and performing secondary mixing on the compounded materials. According to the invention, the premixed mixture and the fiberized binder are uniformly compounded through the second mixing mechanism, so that the fiberized binder is uniformly distributed in the mixture, and the fiberized binder is fully and uniformly mixed with the electrode material and the conductive agent by performing secondary mixing on the compounded material, so that the fiberized binder is uniformly mixed with the electrode material and the conductive agent; therefore, the binder is fully fiberized and is uniformly distributed in the pole piece, and the electrochemical performance of the dry-method pole piece is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery production, and in particular to a mixer and method for dry electrodes. Background Art

[0002] Lithium-ion batteries have been widely used in portable electronic devices, electric vehicles and other fields due to their high energy density and long cycle life. The quality of electrode materials directly affects the performance of the battery. The traditional wet coating process requires the use of a large amount of solvents such as N-methylpyrrolidone (NMP) and deionized water, and these solvents need to be dried and removed through a drying process, resulting in a huge waste of energy and potential harm to the environment. Compared with the traditional wet coating process, the dry electrode film production process does not use any solvents, and the electrode plates can be prepared only by mixing dry powders. The process is simple, there is no drying process, the energy consumption is small, and there is no impact on the environment.

[0003] In the prior art, the dry electrode mixer first mixes the materials (dry materials and adhesives) and then fiberizes the adhesives. However, the fiberized adhesives cannot be evenly distributed in the dry materials, resulting in uneven distribution of the adhesive fibers in the electrode after being pressed into a film, and even the phenomenon of non-fiberization and agglomeration, which leads to poor electrochemical performance of the electrode. Summary of the invention

[0004] The present invention provides a mixer and method for dry electrodes, which are used to solve the defect in the prior art that uneven distribution of binder fibers leads to poor electrochemical performance of electrode sheets.

[0005] The present invention provides a mixer for dry electrodes, comprising: The first mixing mechanism is used for premixing electrode materials and conductive agents; A fiberizing mechanism for fiberizing the binder; The second mixing mechanism is used for compounding the pre-mixed mixture of the electrode material and the conductive agent with the fiberized binder, and for secondary mixing of the compounded materials.

[0006] According to a dry electrode mixer provided by the present invention, a dispersing component is provided below the first mixing mechanism, the upper portion of the dispersing component has a feed port connected to the first mixing mechanism, the lower portion of the dispersing component has a discharge port, and the dispersing component is used to evenly disperse the mixed material and output it from the discharge port; The outlet of the fiberizing mechanism corresponds to the discharge port of the dispersing component.

[0007] According to a dry electrode mixer provided by the present invention, the second mixing mechanism comprises: A fiber composite tank is connected below the dispersion component; the inner cavity of the fiber composite tank is connected to the discharge port; A mixing body connected to the lower side of the fiber composite tank; The fiberizing mechanism is arranged in the fiber composite tank, and the outlet of the fiberizing mechanism is used to apply a post-fiberizing binder to the mixed material output from the discharge port in real time.

[0008] According to a dry electrode mixer provided by the present invention, the dispersing component comprises: A vibrating body, the vibrating body is connected to the first mixing mechanism, and the feed port is arranged on the vibrating body; A bottom plate is located below the vibration body, a dispersion cavity is formed between the vibration body and the bottom plate, and a gap is provided between the edge of the vibration body and the edge of the bottom plate, and the gap serves as the discharge port; The fiberizing mechanism has a plurality of outlets arranged in a circumferential direction, and the outlets face toward the side wall of the fiber composite tank.

[0009] According to a dry electrode mixer provided by the present invention, the second mixing mechanism comprises: A conveying component, wherein a first end of the conveying component is located below the dispersing component; A mixing body at the second end of the conveying member; The fiberizing mechanism is located above the conveying component, and the outlet of the fiberizing mechanism faces the conveying component. The fiberizing mechanism is used to apply a post-fiberization binder to the mixed material on the conveying component in real time.

[0010] According to the dry electrode mixer provided by the present invention, at least one of the dispersing component and the first mixing mechanism and the dispersing component and the second mixing mechanism is connected via a flexible connection.

[0011] According to a mixer for dry electrodes provided by the present invention, a guide member is provided in the dispersing component, and the height of the guide member gradually decreases from a side away from the discharge port to a side close to the discharge port.

[0012] According to a dry electrode mixer provided by the present invention, the fiberizing mechanism comprises: A centrifugal fiberizer, wherein the centrifugal fiberizer has an inlet and an outlet; A driving member connected to the centrifugal fiberizer, the driving member is used to drive the centrifugal fiberizer to rotate; A heating component is used to heat the binder in the centrifugal fiberizer.

[0013] According to a dry electrode mixer provided by the present invention, the first mixing mechanism comprises: Mixing box; A stirring element, arranged in the mixing box; A dispersed driving member, arranged on the side wall of the mixing box; The dispersion disk is arranged in the mixing box and connected to the dispersion driving member.

[0014] A dry electrode mixer according to the present invention also includes: A buffer material box, wherein the buffer material box has a raw material inlet and a raw material outlet communicated with the first mixing mechanism; A weighing piece is arranged on the buffer material box.

[0015] The present invention also provides a method for preparing a dry electrode, based on any one of the above-mentioned dry electrode mixers, the method comprising: Premixing of electrode materials and conductive agents; Fibrosis of binders; The pre-mixed mixture of the electrode material and the conductive agent is compounded with the fiberized binder, and the compounded materials are secondary mixed.

[0016] According to a method for preparing a dry electrode provided by the present invention, the compounding of the mixture obtained by premixing the electrode material and the conductive agent with the fiberized binder comprises: The pre-mixed mixture of the electrode material and the conductive agent is uniformly discharged from the discharge port along the circumferential direction and falls in a barrel shape; After fiberization, the binder is thrown out in an umbrella shape; The fiberized binder thrown out in an umbrella shape is compounded with the mixed material falling in a barrel shape in real time.

[0017] The mixer for dry electrodes provided by the present invention premixes the electrode material and the conductive agent in a first mixing mechanism, and separately fiberizes the binder in a fiberizing mechanism. The premixed mixture and the fiberized binder are uniformly compounded by a second mixing mechanism, so that the fiberized binder is evenly distributed in the mixture. The composited materials are secondarily mixed, so that the fiberized binder is fully mixed with the electrode material and the conductive agent, so that the binder is fully fiberized and evenly distributed inside the electrode sheet, thereby improving the electrochemical properties of the dry electrode sheet and effectively ensuring the comprehensive performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural schematic diagram of a mixer for dry electrodes provided by the present invention.

[0020] Figure 2 This is one of the structural schematic diagrams of the first mixing mechanism provided by the present invention.

[0021] Figure 3 This is the second structural schematic diagram of the first mixing mechanism provided by the present invention.

[0022] Figure 4 It is a structural schematic diagram of the fiberization mechanism provided by the present invention.

[0023] Figure 5 This is one of the flow diagrams of the method for preparing the dry electrode provided by the present invention.

[0024] Figure 6 This is the second schematic flow chart of the method for preparing the dry electrode provided by the present invention.

[0025] Reference numerals: 100, first mixing mechanism; 110, mixing box; 120, stirring element; 130, dispersion driving element; 140, dispersion plate; 150, main shaft driving element; 160, speed reducer; 170, transmission chain; 180, placeholder; 190, discharge port; 200, fiberizing mechanism; 210, centrifugal fiberizer; 220, driving member; 230, outlet; 240, binder material flow; 250, speed increaser; 260, transmission belt; 270, feed pipe; 300, dispersion component; 310, feed port; 320, discharge port; 330, vibration body; 340, bottom plate; 350, dispersion chamber; 360, guide member; 370, vibration motor; 380, electrode material and conductive agent material flow; 390, soft connection; 400, second mixing mechanism; 410, fiber composite tank; 420, mixing body; 500. Buffer mechanism; 600. Filter; 710. First launch tank; 720. Second launch tank; 730. Third launch tank; 740. First unpacking station; 750. Second unpacking station; 760. Third unpacking station; 770. Cantilever crane; 780. Ton bag filled with conductive agent; 800. Finished product barrel. DETAILED DESCRIPTION

[0026] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0027] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0028] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0029] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0030] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0031] Combine the following Figure 1-Figure 4 A mixer for dry electrodes according to an embodiment of the present invention will be described.

[0032] The embodiment of the first aspect of the present invention provides a dry electrode mixer, such as Figure 1 As shown, the dry electrode mixer includes a first mixing mechanism 100 , a fiberizing mechanism 200 and a second mixing mechanism 400 .

[0033] Among them, the first mixing mechanism 100 is used for premixing electrode materials and conductive agents; the fiberizing mechanism 200 is used for fiberizing the binder; the second mixing mechanism 400 is used for compounding the premixed mixture of electrode materials and conductive agents with the fiberized binder, and for secondary mixing of the compounded materials.

[0034] It can be understood that the electrode material and the conductive agent are premixed in the first mixing mechanism 100, and the binder is fiberized in the fiberizing mechanism 200, then the mixing of the dry material (electrode material and conductive agent) and the fiberization of the binder are carried out independently, and the separately fiberized binder is evenly compounded with the premixed mixture of the electrode material and the conductive agent so that the fiberized binder is evenly distributed in the mixture of the electrode material and the conductive agent, and the compounded materials are secondarily mixed by the second mixing mechanism 400 so that the fiberized binder is fully and evenly mixed with the electrode material and the conductive agent.

[0035] The mixer for dry electrodes provided in the embodiment of the present invention premixes the electrode material and the conductive agent in the first mixing mechanism 100, and separately fiberizes the binder in the fiberizing mechanism 200. The premixed mixture and the fiberized binder are uniformly compounded by the second mixing mechanism 400, so that the fiberized binder is evenly distributed in the mixture, and the composite materials are mixed for the second time by the second mixing mechanism 400, so that the fiberized binder is fully mixed with the electrode material and the conductive agent, so that the binder is fully fiberized and evenly distributed inside the electrode sheet, thereby improving the electrochemical properties of the dry electrode sheet and effectively ensuring the comprehensive performance of the battery.

[0036] It should be noted that in the prior art, the electrode material, the conductive agent and the binder are mixed and then sheared at high speed to fiberize the binder; however, during the mixing process, the binder is difficult to be evenly distributed in the dry material (electrode material, conductive agent), resulting in the inability of some binders to fiberize to form agglomerates during the subsequent fiberization process. At the same time, due to the uneven distribution of the formed binder fibers, the stress of the pole pieces in the subsequent pressing process is inconsistent, resulting in poor consistency in the thickness of the pole pieces. In the present invention, the mixing of the dry material (electrode material and conductive agent) and the fiberization of the binder are carried out independently, and the binder after fiberization is evenly compounded with the mixture, so that the fiberized binder is evenly distributed in the mixture, effectively ensuring that the stress of the pole pieces in the subsequent pressing process is consistent, so that the thickness of the pole pieces is more consistent.

[0037] In addition, in the prior art, the electrode material, the conductive agent and the binder are mixed and then subjected to high-speed shearing. The high-speed shearing process usually applies a high shear force, which can easily lead to damage to the electrode material. For example, the surface of the lithium iron phosphate raw material is coated with a carbon layer, which will be destroyed under the action of high-speed shearing, thereby affecting the battery performance. In the present invention, the electrode material and the conductive agent are pre-mixed in the first mixing mechanism 100, and the binder is fiberized in the fiberizing mechanism 200. The mixing of the dry material (electrode material and conductive agent) and the fiberization of the binder are two independent processing processes, so that the mixing of the electrode material and the conductive agent does not involve high-speed shearing, and the mixing process of the electrode material and the conductive agent will not damage the electrode material, effectively ensuring the battery performance.

[0038] In one embodiment of the present invention, Figures 1 to 3 As shown, the first mixing mechanism 100 includes a mixing box 110, a main shaft driving member 150 disposed in the mixing box 110, and a stirring member 120 rotatably disposed in the mixing box 110. The main shaft driving member 150 drives the stirring member 120 to rotate to stir and mix the electrode material and the conductive agent.

[0039] Optionally, the stirring member 120 is a stirring main shaft with a plow blade, and the main shaft driving member 150 is a main shaft driving motor disposed outside the mixing box 110, and the main shaft driving motor is connected to the stirring main shaft through a transmission component. For example, the transmission component includes a first transmission sprocket, a second transmission sprocket and a transmission chain 170, the first transmission sprocket is connected to the output shaft of the main shaft driving motor through a reducer 160, the second transmission sprocket is coaxially connected to one end of the stirring main shaft, and the transmission chain 170 is connected to the first transmission sprocket and the second transmission sprocket.

[0040] Furthermore, the side of the mixing box 110 is provided with an auxiliary stirring component, which includes a dispersion drive component 130 and a dispersion disk 140. The dispersion drive component 130 is a high-speed dispersion motor, and the dispersion drive component 130 is arranged on the side wall of the mixing box 110; the dispersion disk 140 is arranged in the mixing box 110 and connected to the dispersion drive component 130. The auxiliary stirring component can be turned on or the speed can be adjusted as needed, and the speed range is 0-6500rpm.

[0041] Preferably, the first mixing mechanism 100 further includes a placeholder 180 disposed on the mixing box 110, and the placeholder 180 is distributed on the opposite side of the dispersion plate 140, and the placeholder 180 and the dispersion plate 140 are disposed on opposite sides of the mixing box 110. It should be noted that the placeholder 180 of different specifications can be configured on the opposite side of the dispersion plate 140 according to the dispersion effect to ensure the uniformity of stirring, thereby improving the mixing uniformity of the electrode material and the conductive agent.

[0042] In one embodiment of the present invention, the first mixing mechanism 100 has a discharge port 190 at the bottom, and a convergence bucket is connected below the discharge port 190. The mixed material after being stirred and mixed uniformly by the first mixing mechanism 100 is discharged into the second mixing mechanism 400 at the bottom through the discharge port 190 and the convergence bucket. It should be noted that the discharge port 190 of the first mixing mechanism 100 is provided with a discharge valve, and the discharge valve is used to control the opening and closing of the discharge port 190.

[0043] It should be noted that the mixture and the fiberized binder are first compounded in the second mixing mechanism 400, and then mixed for the second time. The fiberized binder is fully mixed with the mixture of the electrode material and the conductive agent by stirring and kneading, and then discharged into the finished product barrel 800 through the discharge port at the bottom of the second mixing mechanism 400. It should be noted here that the second mixing mechanism 400 can adopt the same stirring structure as the first mixing mechanism 100. The second mixing mechanism 400 is also equipped with a plow blade type stirring spindle, and a dispersion drive 130 and a dispersion disk 140 are arranged on the side. The speed can be turned on or adjusted as needed (the speed range is 0-6500rpm), and the opposite side of the dispersion disk 140 can be equipped with different specifications of placeholders 180 according to the dispersion effect to ensure the uniformity of stirring.

[0044] In one embodiment of the present invention, Figure 1 As shown, the mixer also includes a buffer mechanism 500 arranged above the first mixing mechanism 100, and the buffer mechanism 500 includes a buffer box and a weighing piece (not shown in the figure), the upper part of the buffer box has a raw material inlet, and the lower part of the buffer box has a raw material outlet, and the raw material outlet is connected to the feed inlet of the first mixing mechanism 100; the weighing piece is arranged in the buffer box, and is used to weigh the raw materials (electrode material and conductive agent) entering the buffer box.

[0045] Optionally, the buffer material box has a raw material inlet, and the electrode material and the conductive agent both enter the buffer material box through the raw material inlet. The buffer material box collects the raw materials, and the weighing piece measures the raw materials. Of course, the buffer material box can also have two raw material inlets, and the electrode material and the conductive agent are collected in the buffer material box through the two raw material inlets respectively. The electrode material and the conductive agent can be weighed separately, and then two weighing pieces corresponding to the two raw material inlets are provided in the buffer material box, and the two weighing pieces weigh the electrode material and the conductive agent respectively.

[0046] In one embodiment of the present invention, Figure 1 As shown, the mixer also includes a feeding mechanism, which includes a first launching tank 710, a second launching tank 720, and a third launching tank 730. The first launching tank 710 is filled with a binder, the second launching tank 720 is filled with an electrode material, and the third launching tank 730 is filled with a conductive agent. The first launching tank 710 is connected to the fiberizing mechanism 200, and the second launching tank 720 and the third launching tank 730 are connected to the raw material inlet of the buffer box.

[0047] It can be understood that the process of injecting the electrode material into the second launch tank 720 is as follows: the ton bag containing the electrode material is lifted from the ground to the second unpacking station 750 above the second launch tank 720 by the cantilever crane 770, and then the ton bag containing the electrode material is unpacked by the second unpacking station 750 to unload the electrode material into the second launch tank 720. The process of injecting the conductive agent is as follows: the ton bag 780 containing the conductive agent is lifted from the ground to the third unpacking station 760 above the third launch tank 730 by the cantilever crane 770, and then the ton bag 780 containing the conductive agent is unpacked by the third unpacking station 760 to unload the conductive agent into the third launch tank 730. The process of injecting the adhesive is to lift the ton bag containing the adhesive from the ground to the first unpacking station 740 above the first launching tank 710 through the cantilever crane 770, and then unpack the ton bag containing the adhesive through the first unpacking station 740 to unload the adhesive into the first launching tank 710.

[0048] Optionally, the lower part of the second launch tank 720 and the lower part of the third launch tank 730 are connected to the raw material inlet of the buffer material box through pipelines, and the electrode material and the conductive agent are transported to the buffer material box according to the proportion through the second launch tank 720 and the third launch tank 730 respectively. The buffer material box has a weighing part, and the buffer material box can measure while receiving the material.

[0049] Furthermore, a fan is provided on the upper part of the buffer material box, and the electrode material in the second launch tank 720 and the conductive agent in the third launch tank 730 are sucked into the buffer material box by the fan. Figure 1 As shown, a filter 600 is provided between the buffer material box and the fan to prevent the electrode material and the conductive agent from flying out of the fan and to prevent impurities from entering the buffer material box.

[0050] In an optional embodiment of the present invention, the electrode material includes positive and negative active materials, the positive active material includes but is not limited to one or more of lithium iron phosphate, lithium nickel cobalt manganese oxide, lithium cobalt oxide, lithium nickel manganese oxide, lithium-rich manganese base, etc., and the negative active material includes but is not limited to one or more of graphite, silicon carbon, silicon oxygen, lithium titanate, etc. The conductive agent includes but is not limited to one or more of conductive carbon black, graphene, carbon nanotubes, and carbon nanofibers. The binder includes one or more of polytetrafluoroethylene, polyvinylidene fluoride, etc.

[0051] In one embodiment of the present invention, Figure 1 and Figure 4 As shown, a dispersing component 300 is arranged below the first mixing mechanism 100, the upper part of the dispersing component 300 has a feed port 310 connected to the discharge port 190 of the first mixing mechanism 100, and the lower part of the dispersing component 300 has a discharge port 320, and the dispersing component 300 is used to evenly disperse the mixed material and output it from the discharge port 320; the outlet 230 of the fiberizing mechanism 200 corresponds to the discharge port 320 of the dispersing component 300.

[0052] It can be understood that the mixture of the electrode material and the conductive agent premixed by the first mixing mechanism 100 is discharged into the dispersing component 300 through the discharge port 190, and the dispersing component 300 vibrates the mixture uniformly through the discharge port 320. Since the outlet 230 of the fiberizing mechanism 200 corresponds to the discharge port 320 of the dispersing component 300, while the dispersing component 300 vibrates the uniformly distributed mixture, the outlet 230 of the fiberizing mechanism 200 applies the corresponding fiberizing binder to the mixture at the discharge port 320 of the dispersing component 300, so that the fiberizing binder at the outlet 230 of the fiberizing mechanism 200 is compounded with the mixture at the discharge port 320 of the dispersing component 300. It should be noted here that the discharge port 320 of the dispersing component 300 continuously outputs the uniformly distributed mixture, and at the same time, the fiberizing mechanism 200 continuously outputs the corresponding fiberizing binder, so that the fiberizing binder is uniformly distributed in the mixture of the electrode material and the conductive agent.

[0053] In an optional embodiment, the second mixing mechanism 400 includes a fiber composite tank 410 and a mixing body 420; the fiber composite tank 410 is connected to the bottom of the dispersion component 300; the inner cavity of the fiber composite tank 410 is connected to the discharge port 320; the mixing body 420 is connected to the bottom of the fiber composite tank 410; the fiberizing mechanism 200 is arranged in the fiber composite tank 410, and the outlet 230 of the fiberizing mechanism 200 is used to apply post-fiberization binder to the mixture output from the discharge port 320 in real time.

[0054] Specifically, the dispersing component 300 includes a vibrating body 330 and a bottom plate 340, the vibrating body 330 is connected to the first mixing mechanism 100, and the feed port 310 is arranged on the vibrating body 330; the bottom plate 340 is spaced below the vibrating body 330, and a dispersing chamber 350 connected to the feed port 310 is formed between the vibrating body 330 and the bottom plate 340, and there is a gap between the edge of the vibrating body 330 and the edge of the bottom plate 340, and the gap serves as the discharge port 320, so that the mixed material enters the dispersing chamber 350 through the feed port 310, and is evenly vibrated out from the discharge port 320 after being dispersed in the dispersing chamber 350.

[0055] For example, the vibration body 330 includes a dispersion vibration plate and a vibration motor 370 disposed on the dispersion vibration plate, and the discharge port 320 formed by the dispersion vibration plate and the bottom plate 340 is circular. The vibration motor 370 drives the dispersion vibration plate to vibrate, and the mixture in the dispersion vibration plate is evenly vibrated out from the discharge port 320 along the circumferential direction. The vibrated material falls along the edge of the dispersion vibration plate in a waterfall to form an extremely thin cylindrical material layer. It should be noted here that the amount of the mixture falling can be adjusted by adjusting the exciting force and amplitude of the vibration motor 370 and the size of the gap between the edge of the vibration body 330 and the edge of the bottom plate 340.

[0056] The fiberizing mechanism 200 is arranged in the fiber composite tank 410 and is located below the dispersion component 300. The feed port of the fiberizing mechanism 200 is connected to the first launch tank 710 through the feed pipe 270. The fiberizing mechanism 200 has a plurality of outlets 230 arranged along the circumferential direction, and the outlets 230 face the side wall of the fiber composite tank 410. The fiberizing binder thrown out by the fiberizing mechanism 200 and the mixture of the electrode material and the conductive agent falling down by the waterfall are naturally compounded in the fiber composite tank 410, and then naturally fall to the bottom of the fiber composite tank 410. Figure 4 In the figure, the electrode material and conductive agent flow 380 is a mixture of the electrode material and the conductive agent falling in the waterfall, and the binder flow 240 is the fiberized binder thrown out by the fiberizing mechanism 200.

[0057] Optionally, the fiberizing mechanism 200 includes a centrifugal fiberizer 210, a driving member 220 and a heating component. The centrifugal fiberizer 210 is a high-speed centrifugal fiberizer. The driving member 220 adopts a three-phase asynchronous motor. The driving member 220 is arranged at the bottom of the fiber composite tank 410. The output of the driving member 220 is provided with a first transmission wheel. The centrifugal fiberizer 210 is provided with a second transmission wheel. The first transmission wheel and the second transmission wheel are connected by a transmission belt 260. The feed port at the lower part of the centrifugal fiberizer 210 is connected to the first launch tank 710 through a feed pipe 270. The outlet 230 is provided at the upper part of the centrifugal fiberizer 210. Further, a speed increaser 250 is provided between the second transmission wheel and the centrifugal fiberizer 210 to increase the rotation speed of the centrifugal fiberizer 210.

[0058] It can be understood that the first launch tank 710 conveys the binder to the feed port of the centrifugal fiberizer 210, and the three-phase asynchronous motor is driven by the transmission belt 260, and then the speed is increased (0-16500rpm) by the speed increaser 250, so that the centrifugal fiberizer 210 rotates at a high speed. The upper part of the centrifugal fiberizer 210 has a fiberization disk, and a heating component is arranged on the fiberization disk. The heating component can be an electromagnetic heating component or an electric heating wire heating component. When the fiberization disk rotates at a high speed, the fiberization disk is heated by electromagnetic or electric heating wire, so that the binder can be instantly fiberized under the action of high-temperature and high-speed centrifugal force and thrown out in an umbrella shape. The thrown fiberized binder and the electrode and conductive agent mixture falling down in the waterfall are naturally compounded in the fiber composite tank 410 and then naturally fall. For example, the bottom of the fiber composite tank 410 is in a cone shape, and a valve is arranged at the bottom of the fiber composite tank 410. The opening and closing of the valve can realize the discharge of the composite material after the mixture and the fiberized binder are compounded into the mixing body 420 for secondary mixing.

[0059] It should be noted that the heating component may also be disposed outside the centrifugal fibrillator 210, and the binder in the centrifugal fibrillator 210 may be a high-temperature binder by introducing hot air into the centrifugal fibrillator 210 or heating the binder.

[0060] It should be noted that the feeding amount of the adhesive can be controlled by adjusting the air flow speed and feeding speed of the first launching tank 710 .

[0061] It should be noted here that the fiberization process of the centrifugal fiberizer 210 can also be achieved in the following ways: high pressure and high temperature method (including but not limited to high pressure collision, high pressure extrusion, etc.); high temperature and high speed airflow (including but not limited to two-fluid, three-fluid collision, Venturi tube, etc.); high temperature airflow crushing (including Laval nozzle), mechanical crushing + auxiliary airflow, etc.; high speed stirring, high speed dispersion, etc.

[0062] It should be noted here that the vibrating body 330 and the bottom plate 340 of the dispersion component 300 can be polygonal, square or other shapes, and correspondingly, the discharge port 320 can be polygonal, square or other shapes; of course, the discharge port 320 of the dispersion component 300 can also adopt linear injection and other methods, for example, circular rotation, circular screening, circular centrifugal throwing, circular injection and other methods.

[0063] The mixer for dry electrodes provided in the embodiment of the present invention premixes the electrode material and the conductive agent in the first mixing mechanism 100, and the premixed uniform material is evenly dispersed by the dispersing component 300 and then falls along a circular waterfall. Driven by the high-speed centrifugal force, the binder is thrown out and fiberized by the high-temperature centrifugal fiberizer 210; the fiberized binder and the premixed material are evenly compounded in the fiber mixing tank, and the compounded material enters the mixing body 420 through the fiber mixing tank for final mixing. In this way, the binder can be fully fiberized and evenly distributed inside the electrode through vibration dispersion, fiberization, compounding and mixing processes.

[0064] It should be noted that the dry electrode mixer provided in the embodiment of the present invention is more energy-saving and more complete than the traditional mixing and fiberizing equipment because there is no electrode material and conductive agent involved in the fiberizing process. At the same time, there is less binder material in the premixing stage, which can save energy consumption and mixing uniformity of the premix, and protect the electrode material and conductive agent from excessive damage. In this way, the composite process of the present invention can ensure uniform distribution of the binder and sufficient fiberization without damaging the electrode material, thereby improving the electrochemical performance of the final dry electrode sheet.

[0065] Further, such as Figure 1 and Figure 4 As shown, the dispersing component 300 is suspended below the first mixing mechanism 100. Specifically, the mixer of this embodiment further comprises a frame, and the buffer mechanism 500, the first mixing mechanism 100, the dispersing component 300 and the second mixing mechanism 400 are sequentially arranged on the frame from top to bottom, and a spring is arranged on the upper part of the dispersing component 300, and the dispersing component 300 is suspended on the steel frame platform of the frame by the spring.

[0066] Optionally, the dispersing component 300 is connected to the first mixing mechanism 100 via a flexible connection 390 . Specifically, the feed port 310 of the vibration body 330 is connected to the discharge port 190 of the first mixing mechanism 100 via a hose.

[0067] Of course, the dispersion component 300 and the second mixing mechanism 400 can also be connected via a soft connection 390. Specifically, the upper end of the fiber composite tank 410 is connected to the vibration body 330 via a hose, and the discharge port 320 formed between the edge of the vibration body 330 and the edge of the bottom plate 340 is connected to the inner cavity of the fiber composite tank 410.

[0068] Optionally, a guide member 360 is provided in the dispersing component, and the height of the guide member 360 gradually decreases from a side away from the discharge port 320 to a side close to the discharge port 320 .

[0069] Specifically, a guide member 360 is provided on the bottom plate 340, and the height of the guide member 360 gradually decreases from the middle to the outside, so that the guide member 360 forms an inclined surface inclined from the middle to the surroundings, which facilitates the mixture of the electrode material and the conductive agent to move from the middle to the surroundings of the guide member 360. Further, the edge of the bottom plate 340 has an extension extending outward, and there is a dispersion gap between the extension and the side wall of the fiber composite tank 410, so that the mixture in the dispersion component 300 flows out through the discharge port 320 and is evenly dispersed in the extension, and the mixture evenly dispersed on the upper surface of the extension falls along the dispersion gap.

[0070] In another optional embodiment of the present invention, the second mixing mechanism 400 includes a conveying component and a mixing body 420, the first end of the conveying component is located below the dispersion component 300, and the mixing body 420 is connected to the second end of the conveying component; the fiberizing mechanism 200 is located above the conveying component, and the outlet 230 of the fiberizing mechanism 200 faces the conveying component, and the fiberizing mechanism 200 is used to apply a post-fiberization binder to the mixture on the conveying component in real time.

[0071] It can be understood that the dispersing component 300 uniformly vibrates the mixture through the discharge port 320 and uniformly drops it to the first end of the conveying component, and the conveying component uniformly conveys the mixture from the first end to the second end, and at the same time, the outlet 230 of the fiberizing mechanism 200 sprays the fiberizing binder to the mixture on the conveying component, so that in the process of conveying the mixture from the first end of the conveying component to the second end of the conveying component, the fiberizing mechanism 200 sprays the fiberizing binder to the mixture on the conveying component in real time, so that the fiberizing binder at the outlet 230 of the fiberizing mechanism 200 is compounded with the mixture at the discharge port 320 of the dispersing component 300. It should be noted here that the discharge port 320 of the dispersing component 300 continuously outputs a uniformly distributed mixture, and at the same time, the fiberizing mechanism 200 continuously outputs the corresponding fiberizing binder, so that the fiberizing binder is uniformly distributed in the mixture of the electrode material and the conductive agent.

[0072] Based on the dry electrode mixer provided in any of the above embodiments, the embodiments of the present invention further provide a method for preparing a dry electrode, such as Figure 5 As shown, the method includes the following steps 10 to 30.

[0073] Step 10: Premixing of electrode materials and conductive agents.

[0074] Step 20: Fibrillation of the binder.

[0075] Step 30, compounding the pre-mixed mixture of the electrode material and the conductive agent with the fiberized binder, and secondary mixing of the compounded materials.

[0076] It can be understood that the electrode material and the conductive agent are premixed, and the binder is fiberized, then the mixing of the dry material (electrode material and conductive agent) and the fiberization of the binder are carried out independently, and the fiberized binder alone is evenly compounded with the premixed mixture of the electrode material and the conductive agent, so that the fiberized binder is evenly distributed in the mixture of the electrode material and the conductive agent, and the composite materials are secondary mixed to fully and evenly mix the fiberized binder with the electrode material and the conductive agent, so that the binder is fully fiberized and evenly distributed inside the electrode sheet, thereby improving the electrochemical properties of the dry electrode sheet and effectively ensuring the comprehensive performance of the battery.

[0077] Optional, such as Figure 6 As shown, step 30 may specifically include the following steps 31 to 33: Step 31: The pre-mixed mixture of the electrode material and the conductive agent is uniformly discharged from the discharge port along the circumferential direction and falls in a barrel shape.

[0078] Step 32: After fiberization, the binder is thrown out in an umbrella shape.

[0079] Step 33, the fiberized binder thrown out in an umbrella shape is compounded in real time with the mixed material falling in a barrel shape.

[0080] It can be understood that after the electrode material and the conductive agent are pre-mixed by the first mixing mechanism, the dispersion component vibrates the mixture evenly through the discharge port, and the vibrated material falls down along the discharge port of the dispersion component to form an extremely thin barrel-shaped material layer; the binder is instantly fiberized and thrown out in an umbrella shape under the high-temperature and high-speed centrifugal force of the fiberization mechanism, and the fiberized binder thrown out in an umbrella shape is naturally compounded with the electrode and conductive agent mixture falling down in the waterfall in the fiber compounding tank, and then mixed for the second time through the mixing body.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dry electrode mixer, characterized in that: include: The first mixing mechanism is used for premixing electrode materials and conductive agents; A fiberizing mechanism for fiberizing the binder; The second mixing mechanism is used for compounding the pre-mixed mixture of the electrode material and the conductive agent with the fiberized binder, and for secondary mixing of the compounded materials.

2. The dry electrode mixer according to claim 1, characterized in that: A dispersing component is disposed below the first mixing mechanism, the upper portion of the dispersing component has a feed port connected to the first mixing mechanism, the lower portion of the dispersing component has a discharge port, and the dispersing component is used to evenly disperse the mixed material and output it from the discharge port; The outlet of the fiberizing mechanism corresponds to the discharge port of the dispersing component.

3. The dry electrode mixer according to claim 2, characterized in that: The second mixing mechanism comprises: A fiber composite tank is connected below the dispersion component; the inner cavity of the fiber composite tank is connected to the discharge port; A mixing body connected to the lower side of the fiber composite tank; The fiberizing mechanism is arranged in the fiber composite tank, and the outlet of the fiberizing mechanism is used to apply a post-fiberizing binder to the mixed material output from the discharge port in real time.

4. The dry electrode mixer according to claim 3, characterized in that: The dispersing components include: A vibrating body, the vibrating body is connected to the first mixing mechanism, and the feed port is arranged on the vibrating body; A bottom plate is located below the vibration body, a dispersion cavity is formed between the vibration body and the bottom plate, and a gap is provided between the edge of the vibration body and the edge of the bottom plate, and the gap serves as the discharge port; The fiberizing mechanism has a plurality of outlets arranged in a circumferential direction, and the outlets face toward the side wall of the fiber composite tank.

5. The dry electrode mixer according to claim 2, characterized in that: The second mixing mechanism comprises: A conveying component, wherein a first end of the conveying component is located below the dispersing component; A mixing body connected to the second end of the conveying member; The fiberizing mechanism is located above the conveying component, and the outlet of the fiberizing mechanism faces the conveying component. The fiberizing mechanism is used to apply a post-fiberization binder to the mixed material on the conveying component in real time.

6. The dry electrode mixer according to any one of claims 2 to 5, characterized in that: At least one of the dispersing component and the first mixing mechanism, and the dispersing component and the second mixing mechanism is connected via a flexible connection, and / or, A guide member is arranged in the dispersing component, and the height of the guide member gradually decreases from a side far from the discharge port to a side close to the discharge port.

7. The dry electrode mixer according to any one of claims 1 to 5, characterized in that: The fibrosis mechanism comprises: A centrifugal fiberizer, wherein the centrifugal fiberizer has an inlet and an outlet; A driving member connected to the centrifugal fiberizer, the driving member is used to drive the centrifugal fiberizer to rotate; A heating component is used to heat the binder in the centrifugal fiberizer.

8. The dry electrode mixer according to any one of claims 1 to 5, characterized in that: The first mixing mechanism comprises: Mixing box; A stirring element, arranged in the mixing box; A dispersed driving member, arranged on the side wall of the mixing box; The dispersion disk is arranged in the mixing box and connected to the dispersion driving member.

9. The dry electrode mixer according to any one of claims 1 to 5, characterized in that: Also includes: A buffer material box, wherein the buffer material box has a raw material inlet and a raw material outlet communicated with the first mixing mechanism; A weighing piece is arranged on the buffer material box.

10. A method for preparing a dry electrode, characterized in that: Based on the dry electrode mixer according to any one of claims 1 to 9, the method comprises: Premixing of electrode materials and conductive agents; Fibrosis of binders; The pre-mixed mixture of the electrode material and the conductive agent is compounded with the fiberized binder, and the compounded materials are secondary mixed.

11. The method for preparing a dry electrode according to claim 10, characterized in that: The compounding of the pre-mixed mixture of the electrode material and the conductive agent and the fiberized binder comprises: The pre-mixed mixture of the electrode material and the conductive agent is uniformly discharged from the discharge port along the circumferential direction and falls in a barrel shape; After fiberization, the binder is thrown out in an umbrella shape; The fiberized binder thrown out in an umbrella shape is compounded with the mixed material falling in a barrel shape in real time.

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