JP2019202312A - Stirring device - Google Patents

Abstract

To provide a method that can solve the problem and the like that processing efficiency remarkably deteriorates in performing a method in which all constituents included in a stirring object are directly put into a high-speed stirring machine.SOLUTION: The stirring device comprises a container and a rotating member that rotates at high speed just inside an inner wall surface of the container, and stirs a stirring object positioned in a film shape between the rotating member and the inner wall surface by centrifugal force generated by the rotating member. The container has a first input port into which powder components constituting the stirring object are put, a second input port into which components including liquid constituting the stirring object are put, and a discharging mechanism that discharges the stirring object having the powder components and the components including liquid mixed. The discharging mechanism has a discharge tank arranged adjacent to a bottom part of the container, a first discharge port through which the bottom part of the container is communicated with the discharge tank and a second discharge port through which the discharge tank is communicated with the outside.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a stirring device for performing a dispersion treatment, for example, a device used for manufacturing a paint including a battery electrode material.

In addition to power supplies for portable electronic devices, battery demands such as lithium-ion secondary batteries and fuel cells, such as power sources for electric vehicles and the accumulation of power generated by wind and solar power generation facilities, will increase in the future. is expected. Further, there is a demand not only for further improvement of characteristics such as miniaturization, weight reduction, and safety of the battery itself, but also for efficient and low-cost production of batteries having these characteristics.

As an effective means for solving this problem, the inventor of the present application has proposed a method for producing a battery electrode paint or the like using the stirring device system disclosed in Patent Document 1.
The high-speed stirrer included in this stirrer system continuously supplies a stirring object to a high-speed stirrer having a container and a rotating member that rotates at a high speed slightly inside the inner wall surface of the container, and the centrifugal force generated by the rotating member In this state, continuous stirring is performed in a state where a film is present between the rotating member and the inner wall surface.
When the battery electrode coating material is manufactured using this stirring device system, the electrode coating material suitable for improving the performance of the battery can be efficiently manufactured while maintaining high safety of the battery.

However, in the stirrer system, since the stirring target supplied to the high-speed stirrer needs to stir the entire material in advance to average the mixed state, a preliminary stirring step is provided as a previous step.
In the preliminary stirring step, for example, when manufacturing an electrode paint for a lithium ion secondary battery, a stirring object including a plurality of components such as powder, solvent, binder, etc. as an active material is mixed, and the mixed state of the whole material Therefore, it is necessary to perform processing over time using a relatively expensive large apparatus.
For this reason, the method of manufacturing the coating material for battery electrodes using the agitator system has a problem in cost.

As a method for solving this problem, it is effective to adopt a method in which the powder component contained in the object to be stirred is directly put into a high-speed stirrer without going through the preliminary stirring step, and to simplify the apparatus configuration.

International Publication No. WO2012 / 018771

When using a method in which all the components contained in the object to be stirred are directly charged into the high-speed stirrer, it is charged into the container using gravity drop from the container top plate of the high-speed stirrer and discharged from the bottom side of the container. Is efficient.
However, when applying the above-described charging / discharging method in the case where stirring is performed in a state where the rotating member and the inner wall surface exist in a film state by centrifugal force generated by the rotating member, continuous supply of the stirring object is hindered. This causes a problem that the processing efficiency is significantly reduced.
The inventors of the present invention diligently studied to solve this problem, and found that the above problem can be solved by reexamining the structure and arrangement of the discharge mechanism to be stirred in the high-speed stirrer.

Specifically, the stirring device of the present invention includes a container and a rotating member that rotates at a high speed slightly inside the inner wall surface of the container, and the rotating member and the inner wall surface are separated by centrifugal force generated by the rotating member. A stirring device that stirs a stirring target that is present in the form of a film, wherein the container has a first charging port for charging a powder component that constitutes the stirring target, and a liquid that constitutes the stirring target. A second charging port for charging the component to be included, and a discharge mechanism for discharging the stirring target in which the powder component and the component including the liquid are mixed, and the discharge mechanism is disposed adjacent to the bottom of the container. A discharge tank, a first discharge port communicating with the bottom of the container and the discharge tank, and a second discharge port communicating with the discharge tank and the outside (Claim 1).

    Preferably, the first discharge port has a discharge blade for transferring an object to be stirred in the container to the discharge tank (Claim 2). Further, the second discharge blade has the same rotational axis as that of the rotary member, and has a spiral surface groove with respect to the rotary axis. Furthermore, the bottom of the container is horizontal with respect to the rotation axis of the rotating member. Furthermore, the said cylindrical part has a some hole penetrated in the inside / outside direction (Claim 5).

In the stirring object to be charged into the stirring device of the present invention, the component containing the liquid preferably contains a solute component, and the average particle size of the solute component is preferably smaller than the average particle size of the powder component.

As described above, when the container is provided with the first charging port and the second charging port, and the powder component and the liquid-containing component constituting the stirring object are separated into the stirring container, the structure of the stirring object is obtained. Not only can the problem of components staying in the charging path and the formation of lumps in the stirring vessel, but also a film between the rotating member and the inner wall surface due to the centrifugal force of the rotating member. It is possible to further enhance the effect of stirring performed in the state of being allowed to enter.
Further, as described above, the container has a discharge mechanism for discharging the stirring target in which the powder component and the liquid-containing component are mixed, and the discharge mechanism is disposed adjacent to the bottom of the container. And an agitation processing object that rotates at a high speed by a centrifugal force generated by a rotating member, having a first discharge port that communicates the bottom of the container and the discharge tank, and a second discharge port that communicates the discharge tank and the outside. Can be decelerated after being transferred into the discharge tank without decelerating in the container, without hindering the effect of stirring performed in a film state between the rotating member and the inner wall surface, The stirring object can be smoothly discharged out of the container.

Further, as described above, when the first discharge port has the discharge blade for transferring the stirring target object in the container to the discharge tank, the stirring target object is smoothly transferred from the container to the discharge tank. The effect of agitation performed in a state where the object to be agitated is present in the form of a film between the rotating member and the inner wall surface can be more reliably exhibited while suppressing the excessive retention of the agitated object.

In addition, as described above, when the second discharge blade has the same rotating shaft as the rotating member and has a spiral surface groove with respect to the rotating shaft, the stirring process target is rotated at a high speed by the centrifugal force generated by the rotating member. The object to be stirred can be transferred into the discharge tank while suppressing the speed of the object from decelerating in the container, and the effect of stirring performed in the state of being present in the form of a film between the rotating member and the inner wall surface is further improved. It can be surely expressed.

In addition, as described above, when the bottom of the container is horizontal with respect to the rotation axis of the rotating member, a state in which the agitation processed product is present in a film shape between the rotating member and the inner wall surface by the centrifugal force of the rotating member. Therefore, the effect of stirring performed in a film-like state between the rotating member and the inner wall surface can be more reliably exhibited.

In addition, as described above, when the cylindrical portion has a plurality of holes penetrating inward and outward, the component containing the powder component and the liquid charged into the container as described above is immediately brought into the inner part of the rotating member. A stirring process can be performed in a state where the stirring object is fed into the wall surface and the stirring object exists in a film shape, and the stirring object exists in a film shape between the rotating member and the inner wall surface It is possible to further enhance the effect of stirring performed in step (b).

In addition, when the component containing the liquid includes a solute component and the average particle size of the solute component is smaller than the average particle size of the powder component, if the stirring target object including these is processed with a high-speed stirrer, The effect of stirring performed in a state where the stirring target exists in the form of a film between the rotating member and the inner wall surface can be more remarkably exhibited.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

It is a block diagram which shows the stirring apparatus which concerns on this invention. It is a block diagram of the conventional coating material manufacturing apparatus.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.
FIG. 1 is a schematic view showing the internal structure of the stirring device of the present invention. As shown in FIG. 1, the stirring device 1 of the present invention includes a container 2 and a rotating member 7 that rotates at a high speed around a rotating shaft 6 that extends in the vertical direction about the center of the container 2.
The container 2 has a cylindrical inner wall surface 21 and defines a cylindrical space having a predetermined length in the vertical direction. The rotating shaft 6 is rotated at a high speed by a high torque motor (not shown) connected thereto, and the rotating member 7 is also rotated at a high speed.
The rotating member 7 has a cylindrical portion 8 that faces the inner wall surface 21 of the container 2 with a slight gap of about 1 to 10 mm.
A horizontal portion 9 that rotates horizontally is disposed inside the tubular portion 8. The shape of the horizontal portion 9 is a disc shape and is integrally configured so as to be concentric with the cylindrical portion 8. A rotating shaft is connected to the lower surface side of the horizontal portion, and the horizontal portion 9 rotates with the rotating member 7 around the rotating shaft 6 at a high speed.
A first charging port 3 and a second charging port 4 are respectively provided above the top plate of the container 2.
The stirring object 1 is charged into the stirring device 1 separately for a powder component not containing a liquid and a component containing a liquid.
The introduction of the powder component that does not include the liquid is performed via the first input port 3, and the input of the component that includes the liquid is performed via the second input port 4.

As described above, the components of the stirring target charged in the container 2 reach the vicinity of the inner peripheral surface 82 of the cylindrical portion 8 of the rotating member 7 by the action of the rotating member 7 that rotates at high speed, and rotate at high speed. Due to the centrifugal force applied by the cylindrical portion 8 of the member 7, the inner wall surface 21 of the container 2 and the cylinder of the rotating member 7 pass through a plurality of holes (not shown) penetrating in the inner and outer directions of the cylindrical portion 8. It is transferred to a slight gap between the ridges 8.
In a slight gap between the inner wall surface 21 of the container 2 and the outer peripheral surface 81 of the rotating member 7, the stirring target is pressed against the inner wall surface 21 of the container 2 by the action of centrifugal force by the rotating member 7. In the gap between the inner wall surface of the container 2 and a film shape. Furthermore, the stirring object that has been formed into a film turns in the container 2 at a high speed as the rotating member 7 rotates.
At this time, the film-like stirring object continues to receive a strong shearing force between the outer peripheral surface 81 of the rotating rotating member 7 and the inner wall surface of the stationary container 2, and the high level of energy is obtained by the strong energy. Dispersion at is given.
The stirring object processed as described above descends sequentially in the container 2 to reach the bottom 22 of the container 2 and is arranged at the center of the bottom 22 to communicate the bottom 22 of the container and the discharge tank 51. It is transferred to the discharge tank 51 via one discharge port.

The bottom portion 22 of the container 2 is horizontal with respect to the rotation shaft 6 of the rotating member 7 in order to maintain the film formation of the stirring target due to the centrifugal force of the rotating member 7 and swivels on the bottom portion 22 at a high speed. It is usually difficult to efficiently discharge the stirring object from the first discharge port 54 at the center of the bottom 22.
For this reason, the 2nd discharge blade 53 is arrange | positioned in the 1st discharge port 54, and the stirring target object rotated on the bottom part 22 at high speed can be discharged | emitted efficiently from the 1st discharge port 54 of the bottom part 22 center.
The second discharge blade 53 has the same rotating member 7 and rotating shaft 6 and rotates at the same peripheral speed as the rotating member 7 at a high speed.
In addition, a spiral surface groove with respect to the rotation shaft 6 is formed on the surface of the second discharge blade 53.
With the above configuration, the stirring object rotating at a high speed on the bottom 22 is maintained via the first discharge port 54 at the center of the bottom 22 while maintaining the film formation of the stirring object due to the centrifugal force of the rotating member 7. It can be efficiently transferred to the discharge tank 51.

The stirring object transferred to the discharge tank 51 is reduced in rotational speed in the discharge tank 51 and discharged to the outside of the container 2 via the second discharge port 55.
In the discharge tank 51, the 1st discharge blade 52 which has the same rotating member 7 and the rotating shaft 6 is arrange | positioned.
The diameter of the first discharge blade 52 is sufficiently smaller than the diameter of the rotating member 7, and a gentler centrifugal force than that of the rotating member 7 is applied to the stirring object, so that the stirring object from the second discharge port 55 Has a function to promote discharge.

Next, the example which applied the stirring apparatus of this invention and the stirring apparatus of the comparative example to manufacture of the coating material for electrodes of a lithium ion secondary battery is demonstrated.

(Example)
In this example, the stirring device of the present invention shown in FIG. 1 was used, and a positive electrode active material for lithium secondary battery (Ni-Co-Mn (NCM)) powder (average particle size 10.5 μm) was used as a powder component. 1 A charging material slurry is charged from the charging port, and a conductive material slurry containing a conductive material (carbon black) and a binder (PVDF) as components containing liquid is charged from the second charging port. It processed, rotating at 25 m / sec.
(Comparative example)
In this comparative example, a stirring device equivalent to Patent Document 1 shown in FIG. 2 was used.
The stirrer of this comparative example has a preliminary stirring tank 100 for mixing a stirring target object to some extent before processing with the high-speed stirrer 300.
The preliminary stirring tank 100 includes a small-diameter stirring blade 102 that rotates at high speed around a vertical rotation shaft 101 and a large-diameter stirring blade 104 that rotates at a low speed around a vertical rotation shaft 103. The material thrown in from 120 and 130 is accumulated, and both stirring blades 102 and 104 are rotated to preliminarily stir the stirring object.
The stirring target object is mixed by rotating the small-diameter stirring blade 102 at a high speed, and the mixing state of the stirring target object is averaged by rotating the large-diameter stirring blade 104.
Next, the stirring object whose mixing state is averaged is transferred to the high-speed stirrer 300 and processed.

The high-speed stirrer 300 includes a container 310 and a rotating member 330 that rotates at a high speed around a rotating shaft 350 that extends in the vertical direction about the center of the container 310.
The container 310 has a substantially cylindrical inner wall surface 311 and defines a cylindrical space having a predetermined length in the vertical direction. The rotating shaft 350 is rotated at a high speed by a high torque motor 351 mounted on the top of the container 310. A material supply port 314 connected to the lower space is provided at the bottom of the container 310, and a stirring object whose mixing state is averaged is supplied from the material supply port 314. A discharge port 315 connected to the upper space is provided in the upper part of the container 310, and the slurry-like stirred material is discharged to the outside.
In this comparative example, after Ni-Co-Mn-based (NCM) active material powder, conductive material (carbon black) and binder (PVDF) used in the examples were pre-stirred at the same blending ratio as in the examples, The process by the high-speed stirring 300 was performed at the same peripheral speed 25m / sec as the Example.

When the coating materials for the electrodes of the lithium ion secondary batteries of the examples and comparative examples produced as described above were compared, the coating materials of the examples suppressed the formation of conductive material aggregates compared to the coating materials of the comparative example. It was confirmed that re-aggregation of the conductive material can be suppressed for a long period of time, and an electrode coating material suitable for a battery that requires extremely high safety can be produced.

  In the above example, the positive electrode active material for lithium secondary battery (Ni-Co-Mn (NCM)) powder is included as a powder component, and the conductive material (carbon black) and binder (PVDF) are included as components including a liquid. Although the conductive material slurry is used, not only these materials but also other active materials and additives can obtain the same effect.

  The stirring device according to the present invention is not limited to the above-described embodiment. The specific configuration of each part of the stirring device according to the present invention can be varied in design in various ways.

DESCRIPTION OF SYMBOLS 1 Stirring device 2 Container 3 1st inlet 4 Second inlet 5 Discharge mechanism 6 Rotating shaft 7 Rotating member 8 Cylindrical part 9 Horizontal part 10 Mechanical seal 22 Bottom 51 Discharge tank 52 Discharge blade 53 Second discharge blade 54 1st Discharge port 55 Second discharge port 81 Outer peripheral surface 82 Inner peripheral surface 100 Pre-stirring tanks 101 and 103 Rotating shafts 102 and 104 Agitating blades 110 Jacket 120 and 130 Material hopper 140 Discharging port 150 Pump 200 Storage tank 201 Rotating shaft 202 Stirring blades 210 Jacket 220 Pump 300 High-speed stirrer 310 Container 311 Inner wall surface 314 Material supply port 315 Discharge port 330 Rotating member 350 Rotating shaft 351 High torque motor 410 Discharge path 411 Cooling pipe

Claims (6)

A container and a rotating member that rotates at a high speed slightly inside the inner wall surface of the container, and agitates the stirring target that exists in a film shape between the rotating member and the inner wall surface by centrifugal force generated by the rotating member. A stirring device for
The container has a first input port for supplying a powder component constituting the stirring object, a second input port for supplying a component containing a liquid constituting the stirring object, and a component containing the powder component and the liquid A discharge mechanism for discharging the stirring target mixed with
The discharge mechanism is
A discharge tank disposed adjacent to the bottom of the container;
A first discharge port communicating the bottom of the container and the discharge tank;
A stirrer comprising: the discharge tank and a second discharge port communicating with the outside. 2. The stirring device according to claim 1, wherein the first discharge port has a second discharge blade that transfers an object to be stirred in a container to the discharge tank. The stirring device according to any one of claims 1 to 2, wherein the second discharge blade has the same rotation axis as the rotation member and has a spiral surface groove with respect to the rotation axis. The stirring device according to any one of claims 1 to 3, wherein a bottom of the container is horizontal with respect to a rotation axis of the rotating member. The stirrer according to any one of claims 1 to 4, wherein the cylindrical portion has a plurality of holes penetrating in the inner and outer directions. The liquid-containing component includes a solute component,
The stirring device according to claim 1, wherein an average particle size of the solute component is smaller than an average particle size of the powder component.