Powder adjustment unit

Abstract

To provide a powder adjustment unit capable of suppressing the variation in weight by improving the flowability of the powder and making the powder amount uniform.SOLUTION: A powder adjustment unit 10 according to an embodiment includes: a squeegee 3 that vibrates at frequencies between 2 kHz and 300 kHz to give vibrations to powder 4; a pair of fittings 2a and 2b, each curved at a predetermined angle, and arranged at the ends of the squeegee 3; and a pair of vibrators 1a and 1b that are connected to the squeegee 3 in a one-to-one correspondence via the pair of fittings 2a and 2b. The squeegee 3 vibrates in multiple directions at the same time, with multiple different vibration components combined. The multiple vibration components that indicate the multiple directions in which squeegee 3 vibrates include at least an axial component along the longer direction of the squeegee 3.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a powder adjustment unit.

Background Art

[0002] In recent years, a dry coating method of directly coating powder has attracted attention as a method capable of forming a powder layer with high performance and low environmental impact compared to a wet coating method of dispersing powder in a solvent and coating. According to the dry coating method, damage to the powder by the solvent can be suppressed, high performance can be maintained, there is no need to dry the solvent, and a powder layer with a significantly reduced energy consumption can be obtained.

[0003] As a dry coating method for powder, conventionally, a technique of coating powder on the surface of a sheet such as a metal foil while conveying the sheet by a conveying device is known.

[0004] For example, Patent Document 1 discloses a technique of coating powder on the surfaces of a positive electrode and a negative electrode. Patent Document 1 discloses that after supplying powder to the surface of a positive electrode or a negative electrode, the supplied powder is flattened by vibrating the powder with a powder amount adjustment unit, thereby uniformly adjusting the thickness of the powder on the surfaces of the positive electrode and the negative electrode.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in Patent Document 1, the basis weight of the applied powder layer varies. Therefore, when the accuracy of the basis weight is required, there is room for improvement with respect to the variation in the basis weight of the applied powder layer. To improve this, it is conceivable to further improve the fluidity of the powder, but Patent Document 1 has not devised any method for realizing this improvement.

[0007] Therefore, an object of the present disclosure is to provide a powder adjustment unit that can equalize the amount of powder and suppress the variation in basis weight by improving the fluidity of the powder.

Means for Solving the Problems

[0008] The powder adjustment unit according to one aspect of the present disclosure includes a single squeegee that vibrates the powder by vibrating at a frequency of 2 kHz or more and 300 kHz or less, and a pair of joints that are disposed at both ends of the squeegee and curved with a curvature of a predetermined angle, and a pair of vibrators connected to the squeegee so as to correspond one-to-one via the pair of joints. The squeegee vibrates in a plurality of directions simultaneously by combining a plurality of different vibration components, and the plurality of vibration components indicating the plurality of directions in which the squeegee vibrates include at least an axial component along the longitudinal direction of the squeegee.

Effects of the Invention

[0009] According to the powder adjustment unit of the present disclosure, by improving the fluidity of the powder, the amount of powder can be equalized and the variation in basis weight can be suppressed.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

DETAILED DESCRIPTION OF THE INVENTION

[0011] Note that each of the embodiments described below shows comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement positions of components, connection forms, etc. shown in the following embodiments are examples and are not intended to limit the present disclosure. In addition, among the components in the following embodiments, components not described in the independent claims are described as optional components.

[0012] Also, each figure is a schematic diagram that is appropriately emphasized, omitted, or adjusted in ratio to show the present disclosure, and is not necessarily strictly illustrated, and may differ from the actual shape, positional relationship, and ratio. In each figure, the same reference numerals are given to substantially the same configurations, and duplicate descriptions may be omitted or simplified.

[0013] In the following embodiments, expressions such as the vibration direction or circular shape are used. For example, the vibration direction or circular shape not only means that it is completely in the vibration direction or circular shape, but also means that it is substantially in the vibration direction or circular shape, that is, it includes an error of about several percent. Further, the vibration direction or circular shape means the vibration direction or circular shape within the range in which the effects according to the present disclosure can be achieved. The same applies to other expressions using "direction" and "shape".

[0014] (Overview) Hereinafter, a powder adjustment unit according to the present disclosure will be described.

[0015] The powder adjustment unit according to one aspect of the present disclosure improves the fluidity of the powder by applying vibration to the powder, thereby suppressing the clogging of the powder and enabling the uniformization of the amount of the powder. The powder adjustment unit includes a vibrator, a joint (horn), and a squeegee. The vibrator and the squeegee are connected via the joint. The vibrator is a mechanism that generates vibration. The joint has a role of transmitting the vibration to the squeegee and a function of dispersing the vibration direction. The squeegee transmits the vibration to the powder and imparts fluidity to the powder. The structure of the joint is curved with a curvature at a predetermined angle in order to disperse the vibration direction.

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0017] (Embodiment) Hereinafter, this embodiment will be described with reference to FIGS. 1 to 8.

[0018] FIG. 1 is a schematic front view showing a powder adjusting unit 10 according to an embodiment of the present disclosure. Specifically, FIG. 1 is a schematic diagram showing vibrators 1a and 1b, joints (horns) 2a and 2b, and squeegee 3, and shows that the angle formed by the center line of vibrator 1a and the center line of vibrator 1b is arranged at 0° ≤ θ < 45°. FIG. 1 shows the powder adjusting unit 10 as viewed from above. Further, FIG. 2 is a schematic diagram showing a powder layer in which the amount of powder is made uniform by squeegee 3 according to an embodiment of the present disclosure. Further, FIG. 3 is a schematic side view showing the powder adjusting unit 10 according to an embodiment of the present disclosure. Further, FIG. 4 is a schematic front view showing the powder adjusting unit 10 when the posture of the other vibrator 1b is changed with respect to one vibrator 1a according to an embodiment of the present disclosure. Specifically, FIG. 4 is a schematic diagram showing vibrators 1a and 1b, joints 2a and 2b, and squeegee 3, and shows that the angle formed by the center line of vibrator 1a and the center line of vibrator 1b is arranged at 45° ≤ θ ≤ 135°. FIG. 4 shows the powder adjusting unit 10 as viewed from above. Further, FIG. 5 is a schematic side view showing the powder adjusting unit 10 according to an embodiment of the present disclosure. FIG. 5 shows the powder adjusting unit 10 as viewed from the side. Further, FIG. 6 is a schematic front view showing the powder adjusting unit 10 when the posture of the other vibrator 1b is changed with respect to one vibrator 1a according to an embodiment of the present disclosure. Specifically, FIG. 6 is a schematic diagram showing vibrators 1a and 1b, joints 2a and 2b, and squeegee 3, and shows that the angle formed by the center line of vibrator 1a and the center line of vibrator 1b is arranged at 135° < θ ≤ 180°. FIG. 6 shows the powder adjusting unit 10 as viewed from above. Further, FIG. 7 is a schematic side view showing the powder adjusting unit 10 according to an embodiment of the present disclosure. FIG. 7 shows the powder adjusting unit 10 as viewed from the side. FIG. 8 is a diagram showing the vibration direction and the amplitude amount of squeegee 3 when the amplitudes of vibrators 1a and 1b are 0.5 μm.

[0019] [Powder adjusting unit 10] (Overall configuration of the powder adjusting unit 10) First, referring to FIG. 1, the overall configuration of the powder adjustment unit 10 will be described.

[0020] The powder adjustment unit 10 includes a pair of vibrators 1a and 1b, a pair of joints (horns) 2a and 2b, and a squeegee 3. The pair of vibrators 1a and 1b may sometimes be simply referred to as vibrators 1a and 1b, and the pair of joints (horns) 2a and 2b may sometimes be simply referred to as joints (horns) 2a and 2b.

[0021] The vibrators 1a and 1b are connected to the squeegee 3 via the joints 2a and 2b so as to correspond one-to-one with the joints 2a and 2b. Specifically, the vibrators 1a and 1b are Langevin type vibrators. The joints 2a and 2b have the role of transmitting the vibrations of the vibrators 1a and 1b to the squeegee 3. The squeegee 3 has the role of imparting fluidity to the powder 4 supplied onto the sheet 5. The squeegee 3 is vibrating with a plurality of vibration components simultaneously. To vibrate with a plurality of vibration components simultaneously means that a plurality of different vibration components are combined and vibrate in a plurality of directions simultaneously. The plurality of vibration components include components of a three-dimensional orthogonal coordinate system (X direction, Y direction, Z direction) including the axial direction (X direction) along the longitudinal direction of the elongated squeegee 3.

[0022] The squeegee 3 is vibrating at a frequency of 2 kHz or more and 300 kHz or less. That is, by using the vibrators 1a and 1b that vibrate at 2 kHz or more and 300 kHz or less, the squeegee 3 can be vibrated efficiently. This is because when it is assumed to handle the powder 4 having a particle diameter of 0.005 μm or more and 500 μm or less, in order to impart fluidity to the powder 4, high-frequency vibrations of 2 kHz or more and 300 kHz or less are required. And at a low frequency of less than 2 kHz, the number of vibrations is insufficient, and the fluidity of the powder 4 may deteriorate, and there is a risk that sufficient fluidity cannot be imparted to the powder 4.

[0023] As shown in Fig. 2, since the squeegee 3 is in contact with the powder 4, the vibration of the squeegee 3 is transmitted to the powder 4. When the powder 4 vibrates, the frictional resistance between adjacent powders 4 is reduced, so the fluidity of the powder 4 is increased. That is, the powder adjustment unit 10 is a unit that imparts fluidity to the powder 4 and adjusts the amount of powder supplied onto the sheet 5. For example, the powder adjustment unit 10 adjusts the thickness (film thickness of the powder layer) of the supplied powder 4, which is the amount of powder 4 supplied onto the sheet 5. By arranging the squeegee 3 so that a certain gap is formed with respect to the sheet 5 and moving the sheet 5 onto which the powder 4 is supplied in the direction of the arrow in Fig. 2, the amount of powder can be adjusted while aligning the powder 4 by the squeegee 3. Specifically, by adjusting the film thickness and filling rate of the powder layer, variations in the amount of powder are suppressed.

[0024] When the squeegee 3 is not vibrating, the powder 4 also does not vibrate. Therefore, when the powder 4 passes under the squeegee 3, the powder 4 is blocked between the sheet 5 and the squeegee 3, and the fluidity of the powder 4 decreases compared to the case where the powder 4 vibrates, making it difficult to adjust the amount of powder.

[0025] However, in this embodiment, since the squeegee 3 vibrates in a plurality of directions simultaneously, the powder 4 also vibrates in a plurality of directions simultaneously, so the fluidity can be further increased. This is because when focusing on a single particle of the powder 4, a single particle of the powder 4 is in contact with other powders 4 in all directions. Therefore, by imparting vibration components in each direction to a single particle of the powder 4, the frictional resistance between the single particle of the powder 4 and other powders 4 arranged in each direction can be reduced.

[0026] In addition, since the vibration in the Z direction of squeegee 3 is a vibration direction that approaches and separates from powder body 4 with respect to squeegee 3, the collision between powder bodies 4 is repeated in a direction away from squeegee 3. For this reason, vibration is likely to be transmitted from powder body 4 that collides with squeegee 3 to powder body 4 located farther away. At high frequencies of 2 kHz or more and 300 kHz or less, vibration is likely to attenuate, and it is considered that vibration is less likely to be transmitted to powder body 4 located far away. However, in the case of vertical vibration, vibration can be transmitted even to the far side of powder body 4.

[0027] In addition, since the gap between squeegee 3 and sheet 5 can be kept constant, squeegee 3 can impart vibration to powder body 4 so as to precisely control the amount of powder. In particular, the vibration in the Y direction by squeegee 3 also has the effect of imparting vibration to the powder accumulation part of powder body 4 supplied to sheet 5. By imparting vibration to the powder accumulation part, the powder accumulation part can be decomposed.

[0028] However, in the conventional technology, there was no specific method for simultaneously imparting vibration components in a plurality of directions to the powder body. Therefore, the inventors have found that it is possible to simultaneously impart vibration components in a plurality of directions to powder body 4 by the following method.

[0029] In order for squeegee 3 to have a plurality of vibration components, joints 2a and 2b are curved with a curvature at a predetermined angle. Preferably, as shown in FIG. 1, joints 2a and 2b are curved with a right-angle curvature. Thereby, if vibrators 1a and 1b vibrate in the axial direction (Y direction) of vibrators 1a and 1b, the direction components due to the vibration can be dispersed to squeegee 3.

[0030] Note that squeegee 3 and powder body 4 only need to move relative to each other. Specifically, as in the present embodiment, squeegee 3 may be fixed and sheet 5 may be moved relative to squeegee 3. As another example, sheet 5 may be fixed and powder adjustment unit 10, that is, squeegee 3, may be moved relative to sheet 5. As another example, both powder adjustment unit 10 and sheet 5 may be moved.

[0031] In this embodiment, the sheet 5 is a current collector including a metal foil. Note that the material of the sheet 5 is not limited to the current collector, and known materials can be used.

[0032] (Vibration transmitted to squeegee 3) Next, the vibration components transmitted to the squeegee 3 will be described.

[0033] Since the joints 2a and 2b have curvature, the vibration components in the Y direction in the vibrators 1a and 1b are transmitted along the axial direction of the joints 2a and 2b (the broken line indicating the total length W1 of the joints 2a and 2b), so that the squeegee 3 is transmitted as a vibration component in the X direction (axial direction).

[0034] On the other hand, since the joints 2a and 2b are bent at 90°, the vibration components in the Y direction of the vibrators 1a and 1b are also transmitted as vibration components in the Y direction (front-rear direction) of the squeegee 3. That is, due to the vibration components in the Y direction in the vibrators 1a and 1b, the squeegee 3 vibrates at least in the X direction and the Y direction.

[0035] Furthermore, when the joints 2a and 2b are cylindrical, the vibration components in the Y direction of the vibrators 1a and 1b are also slightly transmitted as vibration components in the Z direction (vertical direction) of the squeegee 3. For this reason, the vibration components in the Y direction of the squeegee 3 are slightly dispersed as vibration components in the Z direction of the squeegee 3.

[0036] In this way, the vibration components in the Y direction of the vibrators 1a and 1b are dispersed in the X direction, Y direction, and Z direction, which are the vibration directions of the squeegee 3, through the joints 2a and 2b.

[0037] (Curvature of joints 2a and 2b) Next, the curvature of the joints 2a and 2b will be described.

[0038] Assuming the lengths of the vibrators 1a and 1b are the reference length L, for example, in the case of a Langevin-type vibrator, the reference length L is the length including the front panel, the piezoelectric element, and the backing plate. The curvature is preferably L / 2. By setting the curvature to this value, it is possible to create a state where the vibrators 1a and 1b vibrate not only in the Y direction but also in the X direction, which is the axial direction of the squeegee 3, while transmitting the vibration in the Y direction to the vibration in the X direction. The same effect can be obtained when the curvature is between L / 4 and L. When the curvature is less than L / 4, the vibration propagation in the axial direction of the squeegee 3 becomes weak. When the curvature is greater than L, the joints 2a and 2b become too long, which may cause inconvenience in handling the joints 2a and 2b.

[0039] If you want to increase the ratio of the vibration component in the X direction in the squeegee 3, increase the curvature of the joints 2a and 2b. If you want to increase the ratio of the vibration component in the Y direction in the squeegee 3, decrease the curvature of the joints 2a and 2b.

[0040] (Total length of joints 2a and 2b) Next, the total length of the joints 2a and 2b will be described.

[0041] If the total length of joints 2a and 2b is W1, it is preferable that the total length W1 be the reference length 2L. By setting the total length to W1, the vibration in the Y direction of the vibrators 1a and 1b can be efficiently transmitted to the vibration in the X direction of the squeegee 3. The vibrators 1a and 1b have a structure in which the vibration becomes large in the portion corresponding to the reference length L. Therefore, in the vibrators 1a and 1b, the amplitude becomes large at the period of the reference length L. One vibration component is transmitted along the axial direction of the joints 2a and 2b from the curved portions of the joints 2a and 2b. Therefore, by setting the total length W1 of the joints 2a and 2b to a multiple of L, which is 2L, the vibration in the X direction becomes large at the end faces of the joints 2a and 2b connected to the squeegee 3, and this is transmitted to the squeegee 3, so the vibration in the X direction of the squeegee 3 also becomes large. The same effect can be obtained when the total length W1 is between L and 3L. When the total length W1 is less than L, it becomes difficult to satisfy both the distance W2 and the curvature described later. When it is greater than 3L, the joints 2a and 2b become too long, which may cause inconvenience in handling.

[0042] (Distance W2) Next, the distance W2 will be described.

[0043] Let the distance from the end faces of the vibrators 1a and 1b on the side of the joints 2a and 2b to the center line of the squeegee 3 be W2. The distance W2 is preferably the reference length L. By setting this distance W2, the vibration in the Y direction of the vibrators 1a and 1b can be efficiently transmitted to the vibration in the Y direction of the squeegee 3. The vibrators 1a and 1b have a structure in which the vibration becomes large in the portion corresponding to the reference length L. Therefore, in the vibrators 1a and 1b, the amplitude also becomes large at the period of the reference length L in the Y direction for the components connected to the vibrators 1a and 1b. Therefore, by setting the distance W2 to L, the vibration in the Y direction of the squeegee 3 becomes large. The same effect can be obtained when the distance W2 is between 3L / 5 and 7L / 5. When the distance W2 is less than 3L / 5 or greater than 7L / 5, it becomes difficult to sufficiently transmit the vibration of the vibrators 1a and 1b to the squeegee 3.

[0044] (Widths of joints 2a and 2b) Next, the widths of the joints 2a and 2b will be described.

[0045] The widths of the joints 2a and 2b are preferably 1 / 5 of the reference length L. Also, even if the widths of the joints 2a and 2b are between L / 10 and 2L / 5, the effect of efficiently transmitting the vibrations of the vibrators 1a and 1b to the squeegee 3 can be obtained. When the joints 2a and 2b are cylindrical, the width is the diameter. Note that when the widths of the joints 2a and 2b are smaller than L / 10, the rigidity of the joints 2a and 2b is weak, and the vibrations of the vibrators 1a and 1b in the Y direction are difficult to be transmitted as the vibrations of the squeegee 3 in the Y direction, resulting in a small vibration in the Y direction of the squeegee 3. Also, when the widths of the joints 2a and 2b are larger than 2L / 5, the vibrations of the vibrators 1a and 1b in the Y direction are converted not only into the vibrations of the joints 2a and 2b in the Y direction but also into the components that expand and contract in the radial direction of the joints 2a and 2b, resulting in vibration loss.

[0046] (Diameter of the squeegee 3) Next, the diameter of the squeegee 3 will be described.

[0047] The squeegee 3 preferably has a circular outer periphery such as a cylindrical shape and a cylindrical shape. If the outer periphery of the squeegee 3 has a circular structure, the angle of contact with the powder layer (layer of the powder 4) composed of the powder 4 gradually increases, so it is difficult to form a location where the load on the powder layer from the squeegee 3 locally changes, making it difficult to inhibit the fluidity of the powder 4.

[0048] Also, the diameter of the cross-sectional shape of the squeegee 3, that is, the outer diameter of the squeegee 3, is preferably 1 / 4 or more and 1 or less of the widths of the joints 2a and 2b. If the outer diameter of the squeegee 3 is less than 1 / 4 of the widths of the joints 2a and 2b, the rigidity of the squeegee 3 becomes weak and the squeegee 3 is likely to deform, making it difficult to maintain uniform vibration between the tip and the base of the squeegee 3. Also, if the outer diameter of the squeegee 3 is larger than the widths of the joints 2a and 2b, the squeegee 3 becomes thicker with respect to the joints 2a and 2b, so the vibration from the joints 2a and 2b to the squeegee 3 will be attenuated.

[0049] Also, the outer diameter of the squeegee 3 is preferably about 1 / 2 of the widths of the joints 2a and 2b. This is because when the widths of the joints 2a and 2b are larger than the diameter of the squeegee 3, the vibration is amplified when the vibration from the joints 2a and 2b is transmitted to the squeegee 3, and the squeegee 3 can also maintain the necessary rigidity.

[0050] The outer diameter of the squeegee 3 is preferably 4 mm or more and 40 mm or less. If it is less than 4 mm, the squeegee 3 cannot maintain sufficient rigidity, and if it is larger than 40 mm, the squeegee 3 is less likely to vibrate.

[0051] Note that the squeegee 3 and the joints 2a and 2b may have an integral structure. For example, when the joints 2a and 2b are cylindrical, the squeegee 3 is also cylindrical, and each has the same diameter, the squeegee 3, the joints 2a and 2b may be a series of structures.

[0052] (Particle size of the powder 4) Next, the particle size of the powder 4 will be described.

[0053] The particle diameter (D50) of the powder 4 is preferably, for example, 0.005 μm or more and 500 μm or less. In this case, the smaller the particle diameter (D50) of the powder 4, the more likely the fluidity of the powder 4 is to decrease, but the fluidity of the powder 4 is promoted by the vibration of the squeegee 3. Therefore, the powder 4 is suppressed from staying and aggregating, and is aligned and arranged on the sheet 5, resulting in a high-quality state with little variation in basis weight.

[0054] Here, the particle diameter (D50) is the volume-based median diameter calculated from the measured values of the particle size distribution by the laser diffraction / scattering method or the like. This particle diameter (D50) can be measured using a commercially available laser analysis / scattering type particle size distribution measuring device.

[0055] Here, the basis weight is a value indicating the amount of powder per unit area in terms of weight, and the unit of the basis weight is, for example, g / cm 2 as shown.

[0056] Also, the powder 4 may contain only one type of powder, or may contain two or more types of powders.

[0057] Also, the powder 4 may be granulated powder obtained by consolidating a predetermined amount of powder to make it larger.

[0058] The powder 4 may be any powdery substance. That is, the raw material of the powder 4, the composition of the powder 4, and the particle shape of the powder 4 are not particularly limited. In the present embodiment, the powder 4 is a particle group containing a solid electrolyte.

[0059] (Material and Shape of Squeegee 3) Next, the material and shape of the squeegee 3 will be described.

[0060] The squeegee 3 is formed of, for example, a metal material. By using a metal material for the squeegee 3, high-frequency waves propagate through the squeegee 3 with little attenuation. High-frequency waves with a short wavelength tend to attenuate, but since waves easily propagate through metal materials, the squeegee 3 made of a metal material can suppress the attenuation of high-frequency waves. Therefore, throughout the squeegee 3, the vibration state becomes uniform, and thus variations in the basis weight in the width direction of the powder body 4 are suppressed.

[0061] As the metal material, for example, stainless steel, titanium, aluminum, copper, iron, nickel, etc. are used. In particular, as the metal material, from the viewpoint of high corrosion resistance and difficulty in rusting, stainless steel or titanium is preferable. Further, since titanium is light and easily vibrates with ultrasonic waves, it is more preferable when used as a metal material.

[0062] Note that the squeegee 3 may be formed of a material other than a metal material. For example, the squeegee 3 may be formed of a resin material or a ceramic material, or may be formed of a composite member selectively using two or more materials among a metal material, a resin material, and a ceramic material.

[0063] The squeegee 3 is, for example, a long cylindrical shape extending along a predetermined direction.

[0064] (Vibrators 1a and 1b) Next, the vibrators 1a and 1b will be described.

[0065] The vibrators 1a and 1b each have a plurality of piezoelectric bodies and electrodes provided on end faces of each of the plurality of piezoelectric bodies. In the vibrators 1a and 1b, each of the plurality of piezoelectric bodies is sandwiched between electrodes. That is, the vibrators 1a and 1b have a sandwich structure of a piezoelectric body and an electrode. For example, the number of piezoelectric bodies is an even number such as 2, 4, 6, etc. The electrodes are, for example, thin metal plates made of copper, phosphor bronze, etc.

[0066] As the piezoelectric body, for example, lead zirconate titanate-based (PbTiO 3-PbZrO 3 system, commonly known as PZT), and piezoelectric ceramics such as barium titanate (BaTiO 3 ) may be used. Further, as the piezoelectric body, for example, quartz, and LiNbO 3 and other piezoelectric single crystals may be used.

[0067] When the piezoelectric body is a piezoelectric ceramic (for example, PZT), the piezoelectric body has a thickness of approximately 2 mm or more and 5 mm or less per sheet.

[0068] Further, the vibrators 1a and 1b have a sandwich structure in which a piezoelectric body is sandwiched between a metal front panel and a metal back plate, and a Langevin type vibrator having the overall length thereof as the length of a half wavelength has high output and high reliability and is preferable.

[0069] Specifically, the Langevin type vibrator has a structure in which a metal front panel and a metal back plate arranged on both sides of a piezoelectric body such as PZT are fastened with bolts. The metal front panel and the metal back plate are made of duralumin. The bolts are made of steel or titanium alloy or the like. A screw hole for connecting to the joints 2a and 2b is formed at the center of the metal front panel, and the joints 2a and 2b are inserted into and fastened to the screw hole, so that the vibrators 1a and 1b and the joints 2a and 2b are firmly adhered and connected. Thereby, the vibration generated from the vibrators 1a and 1b can be transmitted to the squeegee 3 via the joints 2a and 2b.

[0070] The vibrators 1a and 1b are vibrators that excite waves, and positive and negative charges are applied to thin metal plates provided on both end faces of the piezoelectric body, respectively. Thereby, electrical energy is converted into mechanical energy. When an electrical signal is converted into mechanical vibration, the vibrators 1a and 1b vibrate at a high frequency. This vibration propagates to the squeegee 3.

[0071] When the vibrators 1a and 1b are long, the polarization directions of piezoelectric bodies such as PZT are preferably aligned with the longitudinal directions of the vibrators 1a and 1b so that the vibrators 1a and 1b expand and contract in their respective longitudinal directions. In this case, since the vibration directions of the vibrators 1a and 1b are in the longitudinal directions of the vibrators 1a and 1b, it becomes easier to control the vibration direction of the generated vibration.

[0072] Also, usually, the vibrators 1a and 1b are equipped with oscillators, and it is possible to give an arbitrary phase difference. By shifting the phases of the vibrators 1a and 1b and vibrating the squeegee 3, it becomes possible to reduce the standing wave ratio indicated by the maximum value / minimum value of the amplitude of the squeegee 3. When the standing wave ratio is reduced, the variation in the basis weight of the obtained powder layer can be reduced.

[0073] (Frequency at which the squeegee 3 vibrates) Next, the frequency at which the squeegee 3 vibrates will be described.

[0074] The squeegee 3 vibrates at a natural frequency of, for example, 2 kHz or more and 300 kHz or less by the vibrators 1a and 1b. That is, the squeegee 3 vibrates at a high frequency near the ultrasonic band. Specifically, when the powder 4 supplied onto the sheet 5 passes through the gap between the squeegee 3 and the sheet 5, the vibration of the squeegee 3 is transmitted to the powder 4, thereby increasing the fluidity of the powder 4. For this reason, powder clogging when the powder 4 passes through the gap between the squeegee 3 and the sheet 5 is suppressed.

[0075] This is because when the squeegee 3 vibrates at a high frequency, the powder 4 in contact with the squeegee 3 is less likely to receive frictional resistance due to powder pressure. As a result, the fluidity of the powder 4 in contact with the squeegee 3 increases, suppressing the retention and aggregation of the powder 4.

[0076] Also, for the powder 4 located near the squeegee 3, the vibration of the squeegee 3 reduces the frictional force between the adjacent powder 4, increasing the fluidity and suppressing the aggregation of the powder 4.

[0077] The fluidity of the powder 4 tends to increase as the frequency of the vibration of the squeegee 3 increases. Therefore, if the squeegee 3 is vibrated at a frequency of 2 kHz or higher, which is a high-frequency region near the ultrasonic band, the fluidity of the powder 4 can be sufficiently increased. However, since vibration tends to attenuate as the frequency increases, it becomes difficult for the vibration of the squeegee 3 to propagate through the powder 4. However, if the frequency is 300 kHz or less, the fluidity of the powder 4 can be sufficiently increased.

[0078] As a result, even when using the powder 4 with a particle size of 500 μm or less and low fluidity, the vibrating squeegee 3 allows the powder 4 to pass through the gap between the squeegee 3 and the sheet 5 without staying or aggregating. Thereby, the film thickness and the filling rate of the powder layer can be adjusted. Therefore, a powder layer with little variation in basis weight can be formed on the sheet 5.

[0079] (Arrangement of the vibrators 1a and 1b) Next, the arrangement of the vibrators 1a and 1b will be described with reference to FIGS. 1 to 7.

[0080] The pair of vibrators 1a and 1b are arranged at a predetermined angle. Specifically, the angle formed by the center line in the axial direction of the vibrator 1a and the center line in the axial direction of the vibrator 1b is set to a predetermined angle, and the pair of vibrators 1a and 1b can be arranged at the predetermined angle. For example, when viewed along the axial direction of the squeegee 3, the arrangement angle, which is the predetermined angle formed by the center line along the axial direction of the vibrator 1a and the center line along the axial direction of the vibrator 1b, is denoted as θ.

[0081] When 0° ≤ θ < 45° as shown in FIGS. 1 and 3, the vibrators 1a and 1b vibrate the squeegee 3 from both sides, increasing the amplitudes in the X, Y, and Z directions, and increasing significantly in the X and Y directions. Also, usually, since the vibrators 1a and 1b each have an oscillator, it is possible to change their respective phases. By arranging the vibrators 1a and 1b at both ends of the squeegee 3 and shifting the phases of the vibrations oscillated from the vibrators 1a and 1b, it is possible to reduce the standing wave ratio indicated by the maximum value / minimum value of the amplitude generated in the squeegee 3. By reducing the standing wave ratio, the intensity variation of the amplitude in the squeegee 3 becomes smaller, and it becomes possible to reduce the thickness variation of the powder layer obtained when the powder 4 passes through the squeegee 3.

[0082] When 45° ≤ θ ≤ 135° as shown in FIGS. 4 and 5, the amplitudes increase in the X, Y, and Z directions as described above, but particularly increase significantly in the Z direction. This is because the vibration oscillated from the vibrator 1a connected to one end of the squeegee 3 is largely dispersed particularly in the X and Y directions through the joint 2a. On the other hand, the vibration oscillated from the vibrator 1b connected to the other end of the squeegee 3 is largely dispersed particularly in the X and Z directions through the joint 2b. When these vibrations with different dispersion directions are transmitted to the squeegee 3, the amplitudes increase significantly in the X, Y, and Z directions. Also, similar to FIGS. 1 and 3 described above, by providing the vibrators 1a and 1b at both ends of the squeegee 3 and shifting the phases of the vibrations oscillated from the vibrators 1a and 1b, it is possible to reduce the standing wave ratio indicated by the maximum value / minimum value of the amplitude generated in the squeegee 3. By reducing the standing wave ratio, the intensity variation of the amplitude in the squeegee 3 becomes smaller, and it becomes possible to reduce the thickness variation of the powder layer obtained when the powder 4 passes under the squeegee 3.

[0083] When 135° < θ ≤ 180° as shown in FIGS. 6 and 7, the obtained effects are the same as those in the cases of FIGS. 1 and 3 described above. The amplitudes in the X, Y, and Z directions increase, and particularly increase significantly in the X and Y directions. Further, by providing the vibrators 1a and 1b at both ends of the squeegee 3 and shifting the phases of the vibrations generated from the vibrators 1a and 1b, the standing wave ratio indicated by the maximum value / minimum value of the amplitude generated in the squeegee 3 can be reduced.

[0084] (Amplitude amount of vibration components in each direction) Next, the amplitude amount of the vibration components in each direction will be described.

[0085] When the squeegee 3 vibrates, the amplitude amount is preferably 0.01 μm or more in two or three of the X, Y, and Z directions when the axial direction of the squeegee 3 is defined as the X direction in a three-dimensional orthogonal coordinate system. In this case, since the frictional resistance between adjacent powders 4 can be sufficiently reduced, the fluidity of the powder 4 can be further enhanced. As a result, since the powder 4 is aligned on the sheet 5, the thickness and basis weight of the powder layer formed by the powder 4 supplied to the surface of the sheet 5 can be adjusted. That is, a powder layer with an adjusted basis weight can be formed on the sheet 5.

[0086] Also, the upper limit value of the amplitude amount when the squeegee 3 vibrates may be, for example, 10 μm or less. In this case, since it is possible to suppress the powder 4 from vibrating too much and scattering as dust, it is possible to suppress contamination of the surroundings.

[0087] Subsequently, the amplitude of the squeegee 3 when the vibrators 1a and 1b vibrate will be described.

[0088] For example, when the shape of the squeegee 3 is a cylindrical shape with a length of 275 mm and a diameter of 8 mm, FIG. 8 shows the relationship between the respective arrangement angles of the vibrators 1a and 1b and the amplitudes in the X, Y, and Z directions in the squeegee 3 when the vibrators 1a and 1b vibrate with amplitudes of 0.5 μm and a frequency of 33 kHz, respectively.

[0089] When the arrangement angles of the vibrators 1a and 1b are 0° ≤ θ < 45°, the amplitudes of the squeegee 3 are 1.31 μm in the X direction, 4.89 μm in the Y direction, and 0.62 μm in the Z direction. It can be seen that the vibrations of the vibrators 1a and 1b are dispersed in each direction, and particularly amplified in the X and Y directions. This is because the vibration components are dispersed in the X and Y directions due to the joints 2a and 2b being bent at 90°, and are slightly dispersed in the Z direction because the joints 2a and 2b are cylindrical.

[0090] When the arrangement angles of the vibrators 1a and 1b are 45° ≤ θ ≤ 135°, the amplitudes of the squeegee 3 are 1.10 μm in the X direction, 4.12 μm in the Y direction, and 4.84 μm in the Z direction. It can be seen that the vibrations of the vibrators 1a and 1b are dispersed in each direction, and amplified in all of the X, Y, and Z directions. This is because the vibrations generated from the vibrator 1a connected to one end of the squeegee 3 are largely dispersed particularly in the X and Y directions through the joint 2a. On the other hand, the vibrations generated from the vibrator 1b connected to the other end of the squeegee 3 are largely dispersed particularly in the X and Z directions through the joint 2b. It is because the vibrations with different dispersion directions are transmitted to the squeegee 3, increasing the amplitude significantly in the X, Y, and Z directions.

[0091] When the arrangement angles of the vibrators 1a and 1b are 135° < θ ≤ 180°, the amplitudes of the squeegee 3 are 1.27 μm in the X direction, 4.78 μm in the Y direction, and 0.59 μm in the Z direction. It can be seen that the vibrations of the vibrators 1a and 1b are dispersed in the three-axis directions, and particularly amplified in the X and Y directions. This is the same as the case where the arrangement angles of the vibrators 1a and 1b are 0° ≤ θ < 45°, because the vibration components are dispersed in the X and Y directions due to the joints 2a and 2b being bent at 90°, and are slightly dispersed in the Z direction because the joints 2a and 2b are cylindrical.

[0092] [Manufacturing Method] Next, a method for manufacturing a powder layer with little variation in basis weight will be described by using the powder adjustment unit 10.

[0093] The method for manufacturing a powder layer includes supplying powder 4 onto the surface of a sheet 5 (powder supply step) while moving the sheet 5 such as a current collector in a predetermined direction, and adjusting the thickness and basis weight of the powder 4 supplied onto the surface of the sheet 5 by using a squeegee 3 (powder alignment step).

[0094] First, powder 4 is produced. The raw material of the powder 4 is not particularly limited. For example, a particle group containing at least one of an active material and a solid electrolyte may be used. When using a particle group containing an active material, a mixture obtained by adding appropriate additives (for example, a binder, a conductive material, and a solid electrolyte, etc.) to the active material is mixed to produce the powder 4. As a method of mixing, for example, there is a method of mixing with a mortar, a ball mill, a mixer, or the like. In particular, a method of mixing the powder 4 without using a solvent or the like is preferable because there is no material deterioration.

[0095] Next, in the powder supply step, while moving the sheet 5 in a predetermined direction, the powder 4 is supplied onto the surface of the sheet 5 by using a powder supply unit such as a hopper. The sheet 5 onto which the powder 4 is supplied may be a member other than a sheet shape, for example, a member such as a plate or a block. In this case, it may be in a form of intermittently transporting a member such as a plate or a block.

[0096] In the powder alignment step, the squeegee 3 is used to align the powder 4 on the sheet 5. That is, in the powder alignment step, the thickness and basis weight of the powder layer formed by the powder 4 supplied onto the surface of the sheet 5 are adjusted by using the squeegee 3. Thereby, a powder layer with the adjusted basis weight is formed on the sheet 5.

[0097] At this time, the squeegee 3 vibrates at a frequency of 2 kHz or more and 300 kHz or less.

[0098] The squeegee 3 is a sinusoidal stationary wave and is resonating (vibrating inherently). The squeegee 3 has amplitudes in multiple directions (X direction, Y direction, Z direction) and is vibrating in multiple directions simultaneously. By having vibration components in multiple directions, the fluidity can be further enhanced. When focusing on a single particle of the powder 4, although a single particle of the powder 4 is in contact with other powders 4 in all directions, by applying vibrations in each direction component to a single particle of the powder 4, the frictional resistance between the single particle of the powder 4 and other powders 4 arranged in each direction can be reduced.

[0099] In order for the squeegee 3 to have multiple vibration components, the joints 2a and 2b are curved with a curvature at a predetermined angle. Preferably, as shown in FIG. 1, the joints 2a and 2b are curved with a right-angle curvature. Thereby, if the vibrators 1a and 1b vibrate in the axial direction (Y direction) of the vibrators 1a and 1b, the direction components due to the vibration can be dispersed to the squeegee 3.

[0100] Also, the method for manufacturing the powder layer may further include a powder sheet-forming step. The powder sheet-forming step compresses the powder layer formed by the powders 4 aligned on the sheet 5 through a roll pressing step using a press machine such as a roll press. Thereby, a compressed powder layer obtained by compressing the powder layer on the sheet 5 is formed.

[0101] As described above, in the method for manufacturing the powder layer, by performing the powder supply step and the powder alignment step in this order, a powder layer composed of the powders 4 is formed on the sheet 5. Such a laminate of the sheet 5 and the powder layer can be used for an energy device. For example, when using a current collector as the sheet 5 and a particle group containing an active material as the powder 4, an electrode for an energy device can be manufactured.

[0102] The fabricated energy device can have a powder layer with low variation in basis weight, which is directly coated after imparting fluidity to the powder 4. Therefore, according to the method for manufacturing the powder layer, the powder 4 is directly coated without using the steps of dispersing the powder 4 in a solvent or the like for coating and then drying it. Thus, deterioration of the material due to the solvent can be suppressed, and high capacity of the energy device can be achieved. Also, the cost increase due to using the solvent and drying the solvent can be suppressed. Furthermore, a large amount of energy consumption in the drying process can be suppressed, resulting in an environmentally friendly manufacturing method. On the other hand, when the uniformity of the basis weight of the powder layer is high, the quality as an electrode in the energy device can be improved, and a high-capacity energy device with good quality can be manufactured at low cost.

[0103] (Powder layer) Next, the powder layer formed using the powder adjustment unit 10 will be described.

[0104] The powder layer according to the present embodiment is used, for example, in an energy device. The film thickness of the powder layer formed on the current collector 5 which is the sheet 5 is 30 μm or more. Also, the powder layer contains the powder 4 composed of at least one kind of particle material. Also, the concentration of the solvent contained in the powder layer is 50 ppm or less. Also, the variation in the basis weight in the powder layer is small.

[0105] Thereby, a powder layer with small variation in basis weight and suppressed deterioration due to the solvent can be formed. Also, since drying of the solvent is not required, the energy consumption for drying the solvent can be reduced, thus suppressing the environmental load and the increase in manufacturing cost. Therefore, by using such a powder layer in an energy device, the capacity and quality of the energy device can be improved, the environmental load can be reduced, and cost reduction can be achieved.

[0106] The powder layer of the present embodiment can be used, for example, in an all-solid-state battery.

[0107] Hereinafter, details of using the powder layer in a all-solid-state battery will be described.

[0108] The powder layer is formed, for example, on a current collector such as sheet 5 and is used as an electrode (positive electrode or negative electrode) of an all-solid-state battery. Such an electrode has a current collector and a powder layer.

[0109] Note that the electrode may further include another layer located between the current collector and the powder layer. The other layer is, for example, a connection layer made of a conductive carbon material or the like.

[0110] The film thickness of the powder layer is 30 μm or more. The upper limit value of the film thickness of the powder layer is not particularly limited, but the film thickness of the powder layer is, for example, 2000 μm or less.

[0111] Also, the powder layer includes powder 4 composed of at least one kind of particle material.

[0112] The concentration of the solvent contained in the powder layer is 50 ppm or less. That is, the powder layer substantially does not contain a solvent. Here, substantially not containing means the case of not containing at all and the case of being unavoidably contained at 50 ppm or less as impurities or the like. The concentration of the solvent is a concentration based on weight.

[0113] The size of the powder layer in plan view is, for example, 30 mm × 30 mm or more. The upper limit of the size of the powder layer in plan view is not particularly limited, but the size of the powder layer in plan view is, for example, 300 mm × 600 mm or less.

[0114] In any 30 mm × 30 mm region on the surface of the powder layer, the variation in the basis weight of the powder layer is, for example, 8% or less.

[0115] As a method for measuring the basis weight, for example, the following method is used.

[0116] First, press the powder layer and the current collector from above and below to compact them. Then, punch out the powder layer and the current collector into a circle with a diameter of 5 mm or more and 9 mm or less, and measure the total weight of the punched-out powder layer and the current collector. And, by subtracting the weight of the current collector of the same lot punched out with a diameter of 5 mm or more and 9 mm or less, which has been measured in advance, from the above total weight, the weight of the powder layer is obtained. By dividing this weight by the area of the circle with a diameter of 5 mm or more and 9 mm or less that has been punched out, the basis weight can be obtained.

[0117] Also, the measurement of the variation in the basis weight is performed, for example, by the following method.

[0118] First, select an arbitrary 30 mm × 30 mm area on the surface of the powder layer in a plan view. This area may be the central area on the surface of the powder layer or an area including the edge of the powder layer. And, within the range of this area, for example, punch out 5 or more circles with a diameter of 5 mm or more and 9 mm or less, and measure the basis weight using the above method. From the viewpoint of improving the accuracy of the variation measurement, it may be punched out at 9 or more locations. The variation in the basis weight is calculated by dividing the difference (specifically, the absolute value of the difference) between the average of the basis weights at all the punched-out locations and the basis weight at the location with the largest difference from the average among the basis weights at each punched-out location by the average. That is, the basis weight variation being 8% or less means that, at any of the punched-out locations, the difference between the basis weight and the average is 8% or less of the average.

[0119] The powder layer is formed, for example, by applying high-frequency vibration to the powder 4 supplied to the surface of the sheet 5 to impart fluidity to the powder 4 and align the powder 4 in the powder layer. Since the squeegee 3 vibrates, the variation in the basis weight in the width direction is small, so a powder layer with a size of 30 mm × 30 mm or more and a thickness of 30 μm or more can be produced with high quality. For this reason, the powder layer can be used for large-sized high-capacity energy devices.

[0120] Also, the powder layer is produced, for example, through a coating process that substantially does not contain a solvent. Therefore, a powder layer that substantially does not contain a solvent can be formed. As a result, the powder layer is not damaged by the solvent. Therefore, deterioration of the powder layer is suppressed, and the variation in the basis weight of the powder 4 in the powder layer is small, so that a powder layer of a large-sized high-capacity energy device having high capacity and excellent quality can be formed.

[0121] Also, the powder layer can be used, for example, for a positive electrode, a negative electrode, or a solid electrolyte layer of an energy device such as an all-solid-state battery.

[0122] When the powder layer is used for the positive electrode, for example, the sheet 5 is a positive electrode current collector, and the powder layer containing the powder 4 is a positive electrode mixture layer. That is, the positive electrode mixture layer is formed on the positive electrode current collector. The powder 4 in the positive electrode mixture layer contains, as at least one type of particle material, a positive electrode active material and a solid electrolyte having ion conductivity.

[0123] When the powder layer is used for the negative electrode, for example, the sheet 5 is a negative electrode current collector, and the powder layer containing the powder 4 is a negative electrode mixture layer. That is, the negative electrode mixture layer is formed on the negative electrode current collector. The powder 4 in the negative electrode mixture layer contains, as at least one type of particle material, a negative electrode active material and a solid electrolyte having ion conductivity.

[0124] When the powder layer is used for the solid electrolyte layer, for example, the powder layer containing the powder 4 is the solid electrolyte layer. The solid electrolyte layer is formed on the surface of the positive electrode mixture layer formed on the positive electrode current collector or on the surface of the negative electrode mixture layer formed on the negative electrode current collector. The powder 4 in the solid electrolyte layer contains, as at least one type of particle material, a solid electrolyte having ion conductivity.

[0125] The concentration of the solvent contained in the positive electrode active material layer, negative electrode active material layer, and solid electrolyte layer is 50 ppm or less. That is, the positive electrode active material layer, negative electrode active material layer, and solid electrolyte layer substantially do not contain the solvent. Here, substantially not containing the solvent means the case where these layers do not contain the solvent at all, and the case where these layers unavoidably contain 50 ppm or less of the solvent as impurities or the like.

[0126] Note that the solvent is, for example, an organic solvent. Further, the measurement method of the solvent is not particularly limited, and for example, it can be measured using gas chromatography, mass change method, or the like. Examples of the organic solvent include nonpolar organic solvents such as heptane, xylene, and toluene, polar organic solvents such as tertiary amine-based solvents, ether-based solvents, thiol-based solvents, and ester-based solvents, and combinations thereof. Examples of the tertiary amine-based solvent include triethylamine, tributylamine, and triamylamine. Examples of the ether-based solvent include tetrahydrofuran and cyclopentyl methyl ether. Examples of the thiol-based solvent include ethanethiol. Examples of the ester-based solvent include butyl butyrate, ethyl acetate, and butyl acetate.

[0127] Next, details of the materials used for the positive electrode active material layer, negative electrode active material layer, and solid electrolyte layer will be described.

[0128] The positive electrode active material is a substance in which metal ions such as lithium (Li) are inserted or removed into or from the crystal structure at a potential higher than that of the negative electrode, and oxidation or reduction occurs with the insertion or removal of metal ions such as lithium. The type of the positive electrode active material is appropriately selected according to the type of the all-solid-state battery, and examples thereof include oxide active materials and sulfide active materials.

[0129] In the present embodiment, for example, an oxide active material (lithium-containing transition metal oxide) is used as the positive electrode active material. Examples of the oxide active material include LiCoO 2 , LiNiO 2 , LiMn 2 O 4 , LiCoPO 4 , LiNiPO 4, LiFePO 4 , LiMnPO 4 Examples thereof include compounds obtained by substituting the transition metals of these compounds with one or two different elements. Examples of the compounds obtained by substituting the transition metals of the above compounds with one or two different elements include LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 , LiNi 0.8 Co 0.15 Al 0.05 O 2 , LiNi 0.5 Mn 1.5 O 2 etc., and known materials are used. The cathode active material may be used alone or in combination of two or more.

[0130] Examples of the shape of the cathode active material include particulate form. When the cathode active material is particulate, the particle diameter of the cathode active material is, for example, in the range of 0.05 μm or more and 30 μm or less, and may be in the range of 1 μm or more and 15 μm or less. If the particle diameter of the cathode active material is 0.05 μm or more, the handleability is likely to be improved. On the other hand, if the particle diameter is 30 μm or less, by using a cathode active material with a small particle diameter, the surface area becomes large, and a high-capacity cathode is easily obtained. Note that the particle diameter of the material contained in the cathode binder layer or the anode binder layer in this specification is, for example, the above-described D50.

[0131] When the ratio of the cathode active material and the solid electrolyte contained in the cathode binder layer is expressed as a weight ratio of cathode active material / solid electrolyte = weight ratio in weight conversion, the weight ratio may be in the range of 1 or more and 99 or less, and may be in the range of 2.3 or more and 19 or less. By being within this weight ratio range, both the lithium ion conduction path and the electron conduction path in the cathode binder layer are easily ensured.

[0132] The anode active material is a substance in which metal ions such as lithium are inserted or removed into or from the crystal structure at a potential lower than that of the cathode, and oxidation or reduction occurs with the insertion or removal of metal ions such as lithium.

[0133] As the negative electrode active material in this embodiment, for example, easily alloyable metals with lithium such as lithium, indium, tin, and silicon, carbon materials such as hard carbon and graphite, and Li 4 Ti 5 O 12 , SiO X and other known materials such as oxide active materials are used. Further, as the negative electrode active material, a composite obtained by appropriately mixing the above-described negative electrode active materials may also be used.

[0134] The particle diameter of the negative electrode active material is, for example, 30 μm or less. By using a negative electrode active material with a small particle diameter, the surface area increases and a high capacity can be achieved.

[0135] When the ratio of the negative electrode active material and the solid electrolyte contained in the negative electrode binder layer is expressed as a weight ratio of negative electrode active material / solid electrolyte = weight ratio in weight conversion, for example, the weight ratio is in the range of 0.6 or more and 19 or less, and may also be in the range of 1 or more and 9 or less. By being within this weight ratio range, it is easy to ensure both the lithium ion conduction path and the electron conduction path in the negative electrode binder layer.

[0136] The solid electrolyte may be appropriately selected according to the conductive ion species (for example, lithium ions). Examples of the solid electrolyte include sulfide-based solid electrolytes, oxide-based solid electrolytes, and halide-based solid electrolytes.

[0137] Although the type of the sulfide-based solid electrolyte in this embodiment is not particularly limited, examples of the sulfide-based solid electrolyte include Li 2 S - SiS 2 , LiI - Li 2 S - SiS 2 , LiI - Li 2 S - P 2 S 5 , LiI - Li 2 S - P 2 O 5 , LiI - Li 3 PO 4 -P 2 S 5 and Li 2 S - P 2 S5 Examples thereof include. In particular, from the viewpoint of excellent lithium ion conductivity, the sulfide-based solid electrolyte may contain Li, P, and S. The sulfide-based solid electrolyte may be used alone or in combination of two or more. Further, the sulfide-based solid electrolyte may be crystalline, amorphous, or glass-ceramics. Note that the above "Li 2 S-P 2 S 5 " description means a sulfide-based solid electrolyte formed using a raw material composition containing Li 2 S and P 2 S 5 and the same applies to other descriptions.

[0138] In this embodiment, one form of the sulfide-based solid electrolyte is a sulfide glass-ceramics containing Li 2 S and P 2 S 5 and the ratio of Li 2 S and P 2 S 5 in terms of molar conversion, when Li 2 S / P 2 S 5 = molar ratio, for example, the molar ratio is in the range of 2.3 or more and 4 or less, and may be in the range of 3 or more and 4 or less. By being within this molar ratio range, a crystal structure with high ionic conductivity can be obtained while maintaining the lithium concentration that affects battery characteristics.

[0139] Examples of the shape of the sulfide-based solid electrolyte in this embodiment include particle shapes such as true spherical and elliptical spherical. When the sulfide-based solid electrolyte material is in particle shape, the particle diameter of the sulfide-based solid electrolyte is not particularly limited, but may be 30 μm or less, 20 μm or less, or 10 μm or less in order to easily improve the filling rate in the positive electrode or negative electrode. On the other hand, the particle diameter of the sulfide-based solid electrolyte may be 0.001 μm or more or 0.01 μm or more.

[0140] Next, the oxide-based solid electrolyte in the present embodiment will be described. The type of the oxide-based solid electrolyte is not particularly limited, but examples include LiPON, Li 3 PO 4 、Li 2 SiO 2 、Li 2 SiO 4 、Li 0.5 La 0.5 TiO 3 、Li 1.3 Al 0.3 Ti 0.7 (PO 4 ) 3 、La 0.51 Li 0.34 TiO 0.74 、Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 and the like. The oxide-based solid electrolyte may be used alone or in combination of two or more.

[0141] Next, the details of the positive electrode current collector and the negative electrode current collector will be described.

[0142] The positive electrode in the present embodiment includes, for example, a positive electrode current collector made of a metal foil or the like. As the positive electrode current collector, for example, a foil-shaped body, a plate-shaped body, a mesh-shaped body, etc. made of aluminum, gold, platinum, zinc, copper, stainless steel (SUS), nickel, tin, titanium, or an alloy of two or more of these are used.

[0143] Also, the thickness, shape, etc. of the positive electrode current collector may be appropriately selected according to the use of the positive electrode.

[0144] The negative electrode in the present embodiment includes, for example, a negative electrode current collector made of a metal foil or the like. As the negative electrode current collector, for example, a foil-shaped body, a plate-shaped body, a mesh-shaped body, etc. made of stainless steel, gold, platinum, zinc, copper, nickel, titanium, tin, or an alloy of two or more of these are used.

[0145] Also, the thickness, shape, etc. of the negative electrode current collector may be appropriately selected according to the use of the negative electrode.

[0146] (Function and effect) The function and effect of the powder adjustment unit 10 in the present embodiment will be described below.

[0147] As described above, the powder adjustment unit 10 of Technology 1 in the present embodiment includes a single squeegee 3 that vibrates the powder 4 by vibrating at a frequency of 2 kHz or more and 300 kHz or less, and a pair of joints 2a and 2b that are arranged at both ends of the squeegee 3 and are curved with a curvature of a predetermined angle, and a pair of vibrators 1a and 1b that are connected to the squeegee 3 so as to correspond one-to-one via the pair of joints 2a and 2b. Further, the squeegee 3 vibrates in a plurality of directions simultaneously by combining a plurality of different vibration components. And the plurality of vibration components indicating the plurality of directions in which the squeegee 3 vibrates include at least an axial component along the longitudinal direction of the squeegee 3.

[0148] For example, when handling powder 4 with a particle size of 0.005 μm or more and 500 μm or less, in order to impart fluidity to the powder 4, high-frequency vibration of 2 kHz or more and 300 kHz or less by the squeegee 3 is required. In this case, if only a low frequency of less than 2 kHz is applied to the squeegee, the number of vibrations imparted from the squeegee to the powder may be insufficient, and the fluidity of the powder may deteriorate, and there is a risk that sufficient fluidity cannot be imparted to the powder.

[0149] However, according to the present embodiment, since the squeegee 3 is in contact with the powder 4, the vibration of the squeegee 3 at a frequency of 2 kHz or more and 300 kHz or less is transmitted to the powder 4. Since the friction resistance between adjacent powders 4 is reduced by the vibration of the powder 4, the fluidity of the powder 4 is increased. Therefore, by moving the sheet 5 to which the powder 4 is supplied in a predetermined direction, the powder 4 can be aligned by the squeegee 3 while adjusting the amount of powder, and by adjusting the film thickness and filling rate of the powder layer, the variation in the amount of powder can be suppressed.

[0150] Therefore, by improving the fluidity of the powder 4, the amount of the powder can be made uniform and the variation in basis weight can be suppressed.

[0151] Further, the powder adjustment unit 10 of Technique 2 in the present embodiment is the powder adjustment unit 10 described in Technique 1. In this case, when the axial direction of the squeegee 3 is defined as the X direction in a three-dimensional orthogonal coordinate system, the amplitude of the squeegee 3 is 0.01 μm or more with respect to two or three directions among the X direction, Y direction, and Z direction.

[0152] According to this, it is possible to suppress the powder 4 from vibrating too much and becoming dust and scattering. For this reason, it is possible to suppress the contamination of the surroundings by the scattered powder 4.

[0153] Further, the powder adjustment unit 10 of Technique 3 in the present embodiment is the powder adjustment unit 10 described in Technique 1 or 2. In this case, when the length of the pair of vibrators 1a and 1b is L, the pair of joints 2a and 2b are curved with a right-angle curvature, L / 4 < curvature < L is satisfied.

[0154] For example, when the curvature is smaller than L / 4, the vibration propagation in the axial direction of the squeegee may become weak. Further, when the curvature is larger than L, the joint may become too long, and inconvenience may occur regarding the handleability of the joint.

[0155] However, according to the present embodiment, it is possible to create a state in which the vibrators 1a and 1b vibrate not only in the Y direction but also in the X direction, which is the axial direction of the squeegee 3, while transmitting the vibration in the Y direction of the vibrators 1a and 1b to the vibration in the X direction.

[0156] Further, the powder adjustment unit 10 of Technique 4 in the present embodiment is the powder adjustment unit 10 described in any one of Techniques 1 to 3. In this case, when the length of the pair of vibrators 1a and 1b is L, the distance W2 between the center line of the squeegee 3 and the end faces of the pair of vibrators 1a and 1b is 3L / 5 < distance W2 < 7L / 5 is satisfied.

[0157] For example, when the distance W2 is less than 3L / 5 and greater than 7L / 5, it may be difficult to sufficiently transmit the vibration of the vibrator to the squeegee.

[0158] However, according to the present embodiment, the vibrators 1a and 1b have a structure in which the vibration becomes large at a portion corresponding to the reference length L. Therefore, in the vibrators 1a and 1b, the amplitude becomes large at the period of the reference length L even in the Y direction for what is connected to the vibrators 1a and 1b. Thus, by setting the distance W2 to L, the vibration in the Y direction of the squeegee 3 becomes large. That is, the vibration in the Y direction of the vibrators 1a and 1b can be efficiently transmitted to the vibration in the Y direction of the squeegee 3.

[0159] Also, the powder adjustment unit 10 of Technique 5 in the present embodiment is the powder adjustment unit 10 described in any one of Techniques 1 to 4. In this case, when the lengths of the pair of vibrators 1a and 1b are L, the total length W1 of the pair of joints 2a and 2b is L ≤ total length W1 ≤ 3L is satisfied.

[0160] For example, when the total length W1 is less than L, it becomes difficult to satisfy both the distance W2 and the curvature. On the other hand, when it is greater than 3L, the joint becomes too long, and there may be inconvenience in handling.

[0161] However, according to the present embodiment, the vibrators 1a and 1b have a structure in which the vibration becomes large at a portion corresponding to the reference length L. For this reason, in the vibrators 1a and 1b, the amplitude becomes large at the period of the reference length L. One vibration component is transmitted along the axial direction of the joints 2a and 2b from the curved portions of the joints 2a and 2b. Therefore, by setting the total length W1 of the joints 2a and 2b to a multiple of L, i.e., 2L, the vibration in the X direction becomes large at the end faces of the joints 2a and 2b connected to the squeegee 3, and this is transmitted to the squeegee 3, so that the vibration in the X direction of the squeegee 3 also becomes large. That is, the vibration in the Y direction in the vibrators 1a and 1b can be efficiently transmitted to the vibration in the X direction in the squeegee 3.

[0162] Further, the powder adjusting unit 10 of Technique 6 in the present embodiment is the powder adjusting unit 10 described in any one of Techniques 1 to 5. In this case, when the lengths of the pair of vibrators 1a and 1b are L, the widths of the pair of joints 2a and 2b are L / 10 ≦ width ≦ 2L / 5 is satisfied.

[0163] For example, when the width of the joint is smaller than L / 10, the rigidity of the joint becomes weak, and the vibration in the Y direction of the vibrator is less likely to be transmitted as the vibration in the Y direction of the squeegee. For this reason, the vibration in the Y direction in the squeegee becomes small. When the width of the joint is larger than 2L / 5, the vibration in the Y direction of the vibrator is converted not only into the vibration in the Y direction of the joint but also into the component that expands and contracts in the radial direction of the joint, resulting in vibration loss.

[0164] However, according to the present embodiment, by setting the widths of the joints 2a and 2b to be not less than L / 10 and not more than 2L / 5, the effect that the vibration of the vibrators 1a and 1b can be efficiently transmitted to the squeegee 3 can be obtained.

[0165] Also, the powder adjustment unit 10 of Technology 7 in the present embodiment is the powder adjustment unit 10 described in any one of Technologies 1 to 6. In this case, the cross-sectional shape when cut along a plane orthogonal to the longitudinal direction of the squeegee 3 is circular. And the diameter of the cross-sectional shape in the squeegee 3 is 1 / 4 or more and 1 or less of the width of the pair of joints 2a and 2b.

[0166] For example, if the outer diameter of the squeegee is less than 1 / 4 of the width of the joint, the rigidity of the squeegee becomes weak and the squeegee is likely to deform, making it difficult to maintain uniform vibration between the tip and the base of the squeegee. On the other hand, if the outer diameter of the squeegee is larger than the width of the joint, the squeegee becomes thicker relative to the joint, and the vibration from the joint to the squeegee is attenuated.

[0167] According to this, by ensuring the rigidity of the squeegee 3, the squeegee 3 can be vibrated uniformly, and the attenuation of vibration from the joints 2a and 2b to the squeegee 3 can be suppressed.

[0168] Also, the powder adjustment unit 10 of Technology 8 in the present embodiment is the powder adjustment unit 10 described in any one of Technologies 1 to 7. In this case, the angle formed by the center lines of one of the vibrators 1a and 1b and the center line of the other vibrator 1b or 1a among the pair of vibrators 1a and 1b is arranged at 0° ≤ θ < 45°.

[0169] According to this, by exciting the squeegee 3 from both sides by the vibrators 1a and 1b, the amplitudes in the X, Y, and Z directions increase, and can increase significantly in the X and Y directions. Also, by arranging the vibrators 1a and 1b at both ends of the squeegee 3 respectively and shifting the phases of the vibrations oscillated from the vibrators 1a and 1b, the standing wave ratio indicated by the maximum value / minimum value of the amplitude generated in the squeegee 3 can be reduced. By reducing the standing wave ratio, the strength variation of the amplitude in the squeegee 3 becomes smaller, and it becomes possible to reduce the thickness variation of the powder layer obtained as the powder 4 passes through the squeegee 3.

[0170] Further, the powder adjustment unit 10 of Technology 9 in the present embodiment is the powder adjustment unit 10 described in any one of Technologies 1 to 7. In this case, the angle formed by the center lines of one of the pair of vibrators 1a and 1b, i.e., either vibrator 1a or 1b, and the center line of the other vibrator 1b or 1a is arranged such that 45° ≤ θ ≤ 135°.

[0171] According to this, the amplitude increases in the X, Y, and Z directions, and particularly increases significantly in the Z direction. Also, similar to the above, by providing vibrators 1a and 1b at both ends of the squeegee 3 and shifting the phase of the vibrations generated from the vibrators 1a and 1b, it becomes possible to reduce the standing wave ratio indicated by the maximum value / minimum value of the amplitude generated in the squeegee 3. By reducing the standing wave ratio, the intensity variation of the amplitude within the squeegee 3 becomes smaller, and it becomes possible to reduce the thickness variation of the powder layer obtained as the powder 4 passes under the squeegee 3.

[0172] Further, the powder adjustment unit 10 of Technology 10 in the present embodiment is the powder adjustment unit 10 described in any one of Technologies 1 to 7. In this case, the angle formed by the center lines of one of the pair of vibrators 1a and 1b, i.e., either vibrator 1a or 1b, and the center line of the other vibrator 1b or 1a is arranged such that 135° < θ ≤ 180°.

[0173] According to this, similar to the above, the amplitudes in the X, Y, and Z directions increase, and particularly increase significantly in the X and Y directions. Also, by providing vibrators 1a and 1b at both ends of the squeegee 3 and shifting the phase of the vibrations generated from the vibrators 1a and 1b, it is possible to reduce the standing wave ratio indicated by the maximum value / minimum value of the amplitude generated in the squeegee 3.

[0174] (Other Modification Examples) As described above, the powder adjustment unit according to the present disclosure has been described based on the embodiments, but the present disclosure is not limited to these embodiments.

[0175] For example, in the powder adjustment unit according to the present disclosure, the squeegee 3 may be provided with a vibration dispersion mechanism. The vibration dispersion mechanism is a plate-shaped member having a polygonal or circular shape and has a circular space in the central portion. The space of the vibration dispersion mechanism is arranged so as to surround the outer periphery of the squeegee 3. In other words, a circular space (through hole) is formed in the vibration dispersion mechanism, and the squeegee 3 is inserted into the circular space. At this time, the clearance between the squeegee 3 and the vibration dispersion mechanism is preferably 5 μm or more and 100 μm or less. In this case, the vibration dispersion mechanism can amplify the vibration component in the Z direction (for example, the vertical direction) of the squeegee 3. The vibration dispersion mechanism is fixed, and the squeegee 3 may contact the lower surface of the circular space in the vibration dispersion mechanism by gravity. This is because the vibration component in the Y direction of the squeegee 3 is likely to be converted into the vibration component in the Z direction by vibrating along the space of the vibration dispersion mechanism.

[0176] Unless departing from the gist of the present disclosure, various modifications conceived by those skilled in the art applied to the embodiments, and other forms realized by arbitrarily combining the components and functions in the embodiments are also included in the scope of the present disclosure.

Industrial Applicability

[0177] The powder adjustment unit of the present disclosure can be applied to uses such as a compound layer of a high-quality all-solid-state battery by forming a uniform powder layer without using a solvent.

Explanation of Signs

[0178] 1a, 1b Vibrators 2a, 2b Joints (horns) 3 Squeegee 4 Powder 5 Member (sheet) 10 Powder adjustment unit W1 Overall length W2 Distance (both end faces of the vibrator on the center line of the squeegee)

Claims

1. A single squeegee that vibrates at a frequency of 2 kHz or more and 300 kHz or less to impart vibration to the powder, A pair of joints arranged at both ends of the squeegee and curved with a curvature of a predetermined angle, A pair of vibrators connected to the squeegee so as to correspond one-to-one via the pair of joints, The squeegee vibrates in a plurality of directions simultaneously by combining a plurality of different vibration components, The plurality of vibration components indicating the plurality of directions in which the squeegee vibrates include at least an axial component along the longitudinal direction of the squeegee, A powder adjustment unit.

2. When the amplitude amount of the squeegee is defined as the X direction in the three-dimensional orthogonal coordinate system with the axial direction of the squeegee as the X direction, it is 0.01 μm or more with respect to two or three directions among the X direction, Y direction, and Z direction, The powder adjustment unit according to claim 1.

3. When the length of the pair of vibrators is L, The pair of joints are curved with a right-angle curvature, Satisfying L / 4 < curvature < L The powder adjustment unit according to claim 1 or 2.

4. When the length of the pair of vibrators is L, The distance between the center line of the squeegee and the end faces of the pair of vibrators is Satisfying 3L / 5 < distance < 7L / 5 The powder adjustment unit according to claim 1 or 2.

5. When the length of the pair of vibrators is L, The total length of the pair of joints is Satisfying L ≤ total length ≤ 3L The powder adjustment unit according to claim 1 or 2.

6. When the length of the pair of vibrators is L, The width of the pair of joints is Satisfying L / 10 ≤ width ≤ 2L / 5 The powder adjustment unit according to claim 1 or 2.

7. The cross-sectional shape when cut in a plane perpendicular to the longitudinal direction of the squeegee is circular, The diameter of the cross-sectional shape in the squeegee is 1 / 4 or more and 1 or less of the width of the pair of joints, The powder adjustment unit according to claim 1 or 2.

8. The angle formed by the center line of one of the pair of vibrators and the center line of the other vibrator is arranged at 0° ≤ θ < 45°, The powder adjustment unit according to claim 1 or 2.

9. The angle formed by the center line of one of the pair of vibrators and the center line of the other vibrator is arranged at 45° ≤ θ ≤ 135°, The powder adjustment unit according to claim 1 or 2.

10.

10.

10.

10.

10. The angle formed by the center line of one of the pair of vibrators and the center line of the other vibrator is arranged such that 135° < θ ≤ 180° The powder adjustment unit according to claim 1 or 2.

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