Powder coating device, method for manufacturing energy device, positive electrode and negative electrode for battery

Abstract

The present disclosure provides a powder coating device, a method for manufacturing an energy device, a positive electrode for a battery, and a negative electrode for a battery. The powder coating device includes a conveyance device (9), a powder supply portion (11), and a squeegee (2). The conveyance device (9) moves a sheet (4) in a given direction. The powder supply portion (11) supplies powder to a surface (4a) of the sheet (4). The squeegee (2) is configured to form a gap between the sheet (4) and the squeegee (2) and adjust a thickness of the powder (3) supplied to the surface (4a) of the sheet (4) by the powder supply portion (11). The squeegee vibrates at a frequency of 2 kHz or more and 300 kHz or less.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a powder coating device, a manufacturing method of an energy device, a positive electrode for a battery, and a negative electrode for a battery. BACKGROUND

[0002] Conventionally, a technique of carrying a member such as a metal foil and coating a powder on a surface of the member is known.

[0003] For example, in Patent Literature 1, a technique of coating a composite material (powder) containing an active material on a surface of a current collector which is a long metal foil is disclosed.

[0004] In Patent Literature 1, it is described that after the powder is supplied to the surface of the metal foil, the powder is flattened by a doctor blade, and thereby the thickness of the powder is adjusted to a uniform thickness. Further, in Patent Literature 1, by performing a granulation process of the powder, the flowability of the powder is improved.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Publication No. 2014-198293 SUMMARY

[0008] A powder coating device according to one embodiment of the present disclosure includes a driving section that moves a member along a given direction; a powder supply section that supplies a powder to a surface of the member; and a doctor blade that is disposed so as to form a gap between the member and the doctor blade, and adjusts a thickness of the powder supplied to the surface of the member by the powder supply section. The doctor blade vibrates at a frequency of 2 kHz or more and 300 kHz or less.

[0009] A manufacturing method of an energy device according to one embodiment of the present disclosure includes: supplying a powder to a surface of a member while moving the member along a given direction; and adjusting a thickness of the powder supplied to the surface using a doctor blade. The doctor blade is disposed so as to form a gap between the member and the doctor blade. The doctor blade vibrates at a frequency of 2 kHz or more and 300 kHz or less.

[0010] A positive electrode for a battery according to one embodiment of the present disclosure includes: a positive electrode current collector; and a positive electrode layer containing a positive electrode active material and formed on the positive electrode current collector, a concentration of a solvent contained in the positive electrode layer is 50 ppm or less, an area of the positive electrode layer is 900 mm 2 The thickness of the positive electrode layer is 15 μm or more, and a deviation of the thickness of the positive electrode layer is ±5% or less.

[0011] One embodiment of the present disclosure relates to a negative electrode for a battery including: a negative electrode current collector; and a negative electrode layer containing a negative electrode active material and formed on the negative electrode current collector, wherein a concentration of a solvent contained in the negative electrode layer is 50 ppm or less, and an area of the negative electrode layer is 900 mm 2 The thickness of the negative electrode layer is 15 μm or more, and a deviation of the thickness of the negative electrode layer is ±10% or less. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a schematic view showing a powder coating device according to one embodiment of the present disclosure.

[0013] Figure 2 is a schematic view showing a part of a powder coating device according to one embodiment of the present disclosure.

[0014] Figure 3A is a schematic view showing a part of a powder coating device according to one embodiment of the present disclosure.

[0015] Figure 3B is a schematic view showing a part of a powder coating device according to one embodiment of the present disclosure.

[0016] Figure 3C is a schematic view showing a part of a powder coating device according to another embodiment of the present disclosure.

[0017] Figure 3D is a schematic view showing a part of a powder coating device according to another embodiment of the present disclosure.

[0018] Figure 3E is a schematic view showing a part of a powder coating device according to still another embodiment of the present disclosure.

[0019] Figure 3F is a schematic view showing a part of a powder coating device according to still another embodiment of the present disclosure.

[0020] Figure 4 is a schematic view showing a part of a powder coating device according to one embodiment of the present disclosure.

[0021] Figure 5 is a schematic view showing a part of a powder coating device according to one embodiment of the present disclosure.

[0022] Figure 6 is a chart showing a manufacturing process of an energy device according to one embodiment of the present disclosure.

[0023] Figure 7 is a cross-sectional view of a positive electrode of an all-solid-state battery according to one embodiment of the present disclosure.

[0024] Figure 8 is a cross-sectional view of a negative electrode of an all-solid-state battery to which one embodiment of the present disclosure relates.

[0025] Figure 9 is a schematic view showing a part of a conventional powder coating device.

[0026] Figure 10 shows a comparison result of a powder film thickness deviation after a doctor blade.

[0027] Figure 11 shows an analysis result of a particle retention ratio.

[0028] Symbol Explanation

[0029] 1: powder coating device;

[0030] 2, 22a, 22b, 22c, 102, 103: doctor blade;

[0031] 2a, 2c, 22a1, 22b1, 22c1, 102a, 103a: main surface;

[0032] 2b: end surface;

[0033] 3: powder;

[0034] 4: sheet (member);

[0035] 4a: surface;

[0036] 5: compressed powder layer;

[0037] 6: roll press (pressing section);

[0038] 9: conveyance device (driving section);

[0039] 11: powder supply section;

[0040] 12: ultrahigh frequency vibration generator;

[0041] 51: positive electrode active material;

[0042] 52: solid electrolyte;

[0043] 53: positive electrode mixture layer;

[0044] 54: positive electrode current collector;

[0045] 61: negative electrode active material;

[0046] 63: negative electrode mixture layer;

[0047] 64: negative electrode current collector;

[0048] A: angle of repose;

[0049] θ: angle DETAILED DESCRIPTION

[0050] As shown in Figure 9 the powder easily remains on the upstream side of the squeegee in the conveyance direction of the metal foil, that is, a bridge easily occurs between the squeegee and the metal foil, in the case where the flowability of the powder is low. In Patent Literature 1, in order to suppress the powder from remaining, the squeegee is vibrated at a frequency of 700 Hz or so. In addition, Figure 9 the hollow arrow in the drawing indicates the conveyance direction of the sheet.

[0051] However, even if the squeegee is vibrated at a frequency of 700 Hz or so as in Patent Literature 1, the remaining of the powder with low flowability cannot be sufficiently suppressed. Furthermore, even in the case where the flowability of the powder is high, it is difficult to make the powder flat so that the thickness of the powder supplied onto the surface of the member becomes uniform with high precision.

[0052] An object of the present disclosure is to provide a powder coating device capable of forming a powder layer with less variation in film thickness on the surface of a member, a method for manufacturing an energy device, a positive electrode for a battery, and a negative electrode for a battery.

[0053] The powder coating device of the present disclosure includes: a driving section that moves a member in a given direction; a powder supply section that supplies a powder onto the surface of the member; and a squeegee that is disposed so as to form a gap between the member and the squeegee and adjust the thickness of the powder supplied onto the surface of the member by the powder supply section. In the powder coating device, the squeegee is vibrated at a frequency of 2 kHz or more and 300 kHz or less.

[0054] According to the present disclosure, a powder layer with less variation in film thickness can be formed on the surface of a member.

[0055] In the powder coating device of the present disclosure, the member is moved by the driving section while the powder is continuously supplied onto the surface of the member by the powder supply section. At this time, the thickness of the powder supplied onto the surface of the member is adjusted to be substantially the same as the width of the gap by the powder supplied onto the surface of the member passing through the gap between the squeegee and the surface of the member. At this time, the powder is pressed by the squeegee when the powder comes into contact with the squeegee, and thus the powder remains and aggregates between the squeegee and the member, and powder clogging easily occurs. However, in the powder coating device of the present disclosure, the squeegee is vibrated at a frequency of 2 kHz or more and 300 kHz or less, and thus the flowability of the powder can be improved, and thus the powder is less likely to remain and aggregate, and powder clogging can be suppressed.

[0056] The embodiments described below show general or specific examples. The numerical values, shapes, materials, component configurations, positions of components, connection methods, steps, order of steps, and the like shown in the following embodiments are one example, and the gist is not intended to be limited to the disclosure. Furthermore, for components in the following embodiments that are not described in the independent technical solution, the components are described as arbitrary components.

[0057] Furthermore, the drawings are schematic and not necessarily strictly to scale. Furthermore, in the drawings, the same reference numerals are assigned to the same structural components. Furthermore, in the following embodiments, expressions such as substantially parallel are used. For example, substantially parallel means not only exactly parallel, but also substantially parallel, that is, for example, including an error of several percent. Furthermore, substantially parallel means parallel within a range in which the effects based on the disclosure can be achieved. The same applies to other expressions in which substantially is used.

[0058] Hereinafter, the embodiments of the disclosure will be described with reference to the drawings as appropriate. Figure 1 The embodiments will be described while referring to the drawings. However, detailed description beyond what is needed is sometimes omitted. For example, detailed description for matters that are already known, repeated description of substantially the same structure is sometimes omitted. This is to avoid the following description from becoming unnecessarily lengthy, so as to make it easy for those skilled in the art to understand.

[0059] Hereinafter, the embodiments of the disclosure will be described with reference to the drawings as appropriate. Figure 1 The embodiments of the disclosure will be described while referring to the drawings as appropriate.

[0060] (Embodiment)

[0061] Hereinafter, with reference to Figures 1-2 , a powder coating device 1 as one embodiment of the powder coating device related to the disclosure will be described.

[0062] The powder coating device 1 is a device that coats a powder 3 on a surface 4a of a sheet-shaped member (hereinafter also referred to as a sheet 4) while carrying the sheet 4 by a carrying device 9 as a driving unit. In detail, the powder coating device 1 is a device that carries the sheet 4 by the carrying device 9, continuously supplies the powder 3 to the surface of the sheet 4 using a powder supply part 11, and continuously compresses the sheet 4 and the powder 3 on the sheet 4 together using a roll press 6, thereby forming a compressed powder layer 5 on the surface of the sheet 4.

[0063] The conveyance device 9 is a driving unit that moves the sheet 4 in a given direction, and is not particularly limited as long as it can convey the sheet 4. In the present embodiment, the conveyance device 9 continuously draws out the sheet 4 wound in a roll shape, but is not limited thereto, and the conveyance device 9 can intermittently draw out the sheet 4. The conveyance device 9 is one example of a driving unit. In the case where the wound sheet 4 is continuously conveyed as in the present embodiment, the sheet 4 on which the compressed powder layer 5 is formed on the surface 4a can be wound in a roll shape again and recycled. In addition, a guide roller that rotates along with the movement of the sheet 4, a control device that corrects the curved travel of the sheet 4, or the like can be provided on the conveyance path of the sheet 4.

[0064] In the present embodiment, the sheet 4 is a long thin plate and is wound, but the member is not limited to such a sheet 4. A new sheet 4 can be drawn out from the conveyance device 9 after the sheet 4 of a desired shape is drawn out from the conveyance device 9 and the coating of the powder 3 is completed. In addition, the sheet 4 can not be wound in a roll shape. The member is not limited to the sheet 4, and is only required to be a shape that can be coated with the powder 3 using the powder coating device 1. In addition, in the present embodiment, the sheet 4 is a current collector including a metal foil, but the material is not particularly limited, and any material that can be coated with the powder 3 using the powder coating device 1 can be used.

[0065] The powder 3 is only required to be a powder-like substance, and the raw material, the component, and the particle shape are not particularly limited. In the present embodiment, the powder 3 is a particle group including an active substance.

[0066] The average particle diameter (D50) of the powder 3 is preferably 0.005 μm or more and 50 μm or less. In this case, the flowability of the powder 3 easily decreases, but since the stagnation and the agglomeration of the powder 3 can be suppressed by the vibration of the doctor blade 2, the compressed powder layer 5 having a small deviation in thickness can be formed on the surface 4a of the sheet 4. In addition, the average particle diameter (D50) is a median diameter on a volume basis calculated from the measured value of the particle size distribution based on the laser diffraction / scattering method, and can be measured using a commercially available laser analysis / scattering type particle size distribution measuring device.

[0067] The powder 3 can contain only one kind of powder, or two or more kinds of powder. In the case where the powder 3 is a mixed powder containing a plurality of kinds of powder, in the case where high-frequency vibration in the vicinity of the ultrasonic wave band is applied to the doctor blade 2 to planarize the powder 3, the dispersibility of the plurality of kinds of powder in the powder 3 is improved. That is, in the powder 3, the plurality of kinds of powder easily disperse in each other, and a particular kind of powder is not easily stacked on the sheet 4 in an unbalanced manner. This is considered to be because, due to the high-frequency vibration in the vicinity of the ultrasonic wave band of the doctor blade 2, the high-frequency vibration in the vicinity of the ultrasonic wave band is also transmitted to a portion where the powder 3 stagnates before reaching the doctor blade 2, the plurality of kinds of particles constituting the powder 3 vibrate and flow, and thus the plurality of kinds of particles constituting the powder 3 mix with each other, thereby improving the dispersibility.

[0068] In the present embodiment, a hopper is used as the powder supply part 11. The hopper stores the powder 3 inside, and supplies the powder 3 onto the surface 4a of the sheet 4. The hopper is disposed at a position further upstream of the sheet 4 than a position where the outer circumferential surfaces of a pair of roll presses 6 described later are closest to each other (hereinafter also referred to as a "pressing position"). The powder 3 supplied onto the surface 4a of the sheet 4 reaches the pressing position as the sheet 4 moves. In the present embodiment, a hopper is used as the powder supply part 11, but the present application is not limited thereto, and any device that can supply the powder 3 onto the surface 4a of the sheet 4 can be used.

[0069] The compressed powder layer 5 is a layer formed by compressing the powder 3.

[0070] As shown in FIG. 1, the powder coating apparatus 1 can also have a pair of roll presses 6 as a pressing part. The pair of roll presses 6 compresses the powder 3 on the sheet 4 whose thickness is adjusted by the doctor blade 2. Figure 1

[0071] The pair of roll presses 6 are each a cylindrical shape, and are disposed so that the shafts of the pair of roll presses 6 are substantially parallel to each other. As shown in FIG. 2, the pair of roll presses 6 are disposed so as to sandwich the sheet 4 with a given gap therebetween. In detail, the outer circumferential surface of one roll press 6 is disposed to face one surface of the sheet 4, and the outer circumferential surface of the other roll press 6 is disposed to face the back surface of the other side of the sheet 4. The pair of roll presses 6 are rotationally driven in opposite directions (the directions of the arrows in FIG. 2) by a driving device (not shown). Figure 1 Figure 1

[0072] The powder coating apparatus 1 has the doctor blade 2. The doctor blade 2 makes the film thickness of the powder 3 supplied onto the surface 4a of the sheet 4 uniform, to reduce the variation in the film thickness. That is, the doctor blade 2 adjusts the thickness of the powder 3 supplied onto the surface 4a of the sheet 4 by the powder supply part 11.

[0073] ​​​Further, the doctor blade 2 is disposed at a position on the downstream side of the hopper and on the upstream side of the pressing position in the moving direction of the sheet 4 in such a manner as to form a given gap between the sheet 4.

[0074] In the powder coating device 1 of the present embodiment, the powder 3 supplied to the surface 4a of the sheet 4 is leveled by the doctor blade 2 during a period until the sheet 4 reaches the pressing position with the movement of the sheet 4. Then, at the pressing position, the powder 3 supplied to the surface of the sheet 4 is pressed on the surface of the sheet 4. In this way, the compressed powder layer 5 is formed on the surface 4a of the sheet 4.

[0075] Hereinafter, the doctor blade 2 will be described in detail with reference to Figure 1 and Figure 2 .

[0076] The doctor blade 2 adjusts the thickness (vertical dimension in FIG. 1) of the powder 3 supplied to the surface 4a of the sheet 4 to be constant by flattening the powder 3. A given gap is formed between the doctor blade 2 and the sheet 4, and the powder 3 supplied to the surface 4a of the sheet 4 passes through the gap. Thus, the thickness of the powder 3 is changed to the shortest distance d between the front end of the doctor blade 2 (the portion opposed to the surface 4a) and the surface 4a of the sheet 4. Figure 2 Further, the doctor blade 2 is preferably configured to be movable with respect to the sheet 4 so as to be able to change the distance d.

[0077] In the present embodiment, the doctor blade 2 has a trapezoidal shape as viewed from the side as shown in FIG. 1. The doctor blade 2 has a main face 2a opposed to the surface 4a of the sheet 4 and inclined with respect to a plane parallel to the surface 4a, and an end face 2b substantially parallel to the sheet 4.

[0078] Figure 1 The main face 2a is inclined downward along the moving direction of the powder 3, and is a face intersecting the moving direction of the powder 3 supplied to the surface 4a. The powder 3 is leveled with respect to the surface 4a by the main face 2a coming into contact with the moving powder 3.

[0079] The end face 2b is a face formed along the moving direction of the powder 3 and substantially parallel to the surface 4a. The end face 2b further levels the surface of the powder 3 leveled by the lower end edge (the edge closest to the surface 4a) of the main face 2a to a given length. The given length is the length of the end face 2b in a direction parallel to the moving direction. Further, the end face 2b is not necessarily required, and a pointed portion can be provided instead of the end face 2b.

[0080] The end face 2b is a face formed along the moving direction of the powder 3 and substantially parallel to the surface 4a. The end face 2b further levels the surface of the powder 3 leveled by the lower end edge (the edge closest to the surface 4a) of the main face 2a to a given length. The given length is the length of the end face 2b in a direction parallel to the moving direction. Further, the end face 2b is not necessarily required, and a pointed portion can be provided instead of the end face 2b.

[0081] (Mechanism of Stagnation)

[0082] ​The powder 3 comes into contact with the main surface 2a of the blade 2 as it approaches the gap between the blade 2 and the sheet 4 along with the movement of the sheet 4. At this time, since the powder 3 is pressed by the movement of the sheet 4 relative to the blade 2, in the case of the powder 3 having low fluidity, the powder 3 is retained and agglomerated between the blade 2 and the sheet 4, and thus powder clogging is easily generated.

[0083] In particular, in the case of using the powder 3 having a particle diameter of 50 μm or less, the fluidity easily decreases, and thus powder clogging is easily generated.

[0084] Further, in the powder 3 having high fluidity as well, the film thickness of the powder 3 after passing through the blade 2 is difficult to be made uniform with high precision due to the influence of the retention. This is because the retention and release of the powder 3 are repeated in a small range.

[0085] (High-frequency vibration in the vicinity of the ultrasonic wave band)

[0086] The blade 2 is connected to an ultrahigh-frequency vibration generator 12 for vibrating the blade 2. Specifically, the blade 2 is vibrated in the vicinity of the ultrasonic wave band by the ultrahigh-frequency vibration generator 12 imparting high-frequency vibration in the vicinity of the ultrasonic wave band to the blade 2. The ultrahigh-frequency vibration generator 12 is capable of vibrating the blade 2 at a frequency of 2 kHz or more and 300 kHz or less. In addition, the ultrahigh-frequency vibration generator 12 can be included in the structural components of the powder coating apparatus 1 or can not be included in the structural components of the powder coating apparatus 1.

[0087] The blade 2 is vibrated at a frequency of 2 kHz or more and 300 kHz or less when the sheet 4 is moved. That is, the blade 2 is vibrated in the vicinity of the ultrasonic wave band when the sheet 4 is moved. By vibrating the blade 2 in the vicinity of the ultrasonic wave band, the vibration of the blade 2 is transmitted to the powder 3, and thus the fluidity of the powder 3 is improved, and thus powder clogging is suppressed.

[0088] The higher the frequency of the vibration of the blade 2, the more easily the fluidity of the powder 3 is increased. Thus, by vibrating the blade 2 at a frequency of 2 kHz or more in the high-frequency region in the vicinity of the ultrasonic wave band, the fluidity of the powder 3 can be sufficiently improved. However, since the high-frequency vibration in the vicinity of the ultrasonic wave band has a property of easily attenuating if the frequency is too high, the vibration becomes more difficult to transmit the farther away from the blade 2. Thus, if the frequency is 300 kHz or less, the fluidity of the powder 3 can be sufficiently improved even at a portion where powder clogging is easily generated. By vibrating the blade 2 in the vicinity of the ultrasonic wave band, the powder 3 in contact with the blade 2 is not easily subjected to frictional resistance caused by the powder pressure, and thus the fluidity is improved, and thus the retention and agglomeration of the powder 3 are suppressed.

[0089] Further, also with respect to the powder 3 located near the doctor blade 2, the frictional force between the particles of the powder 3 is reduced due to the vibration effect by the doctor blade 2, the flowability is improved, and thus the powder aggregation is suppressed.

[0090] Thus, also with respect to the powder 3 having a particle diameter of 50 μm or less and low flowability, the powder 3 passes without being retained or aggregated due to the vibrating doctor blade 2.

[0091] Further, even with respect to the powder 3 having high flowability, the flow can be further promoted, and thus the film thickness of the powder 3 after passing through the doctor blade 2 can be further uniformly made with high accuracy.

[0092] (Direction and magnitude of high frequency vibration near the ultrasonic wave band)

[0093] The direction of the high frequency vibration of the doctor blade 2 near the ultrasonic wave band includes at least one of a vertical direction component, a horizontal direction component, and a face direction component. That is, the doctor blade 2 vibrates in at least any one of the vertical direction, the horizontal direction, and the face direction.

[0094] The so-called vertical direction is a direction perpendicular to the main surface 2a of the doctor blade 2. In the embodiment shown in Figure 1 In the embodiment shown in FIG. 1, the vertical direction is substantially parallel to the X direction. The vibration in the vertical direction is easily transmitted as a longitudinal wave with respect to the powder 3 (a wave from the vibration direction in which the doctor blade 2 approaches or moves away from the powder 3).

[0095] The vertical direction component has a large effect of reducing the frictional resistance between the powder 3. With respect to the vibration in the vertical direction, since it is the vibration direction in which the doctor blade 2 approaches or moves away from the powder 3, the particles of the powder 3 repeatedly collide with each other, and thus the vibration is easily transmitted to the entire powder 3. It is also considered that the frequency of the high frequency near the ultrasonic wave band is high, and thus the vibration becomes difficult to be transmitted to the entire powder 3, but if it is the vibration in the vertical direction, the vibration is particularly easily transmitted with respect to the powder 3.

[0096] In particular, the vertical direction vibration component can greatly move the powder 3 in the aggregation portion in which the powder 3 easily aggregates. Thus, in the aggregation portion, the particles of the powder 3 more easily collide with each other, and thus the powder 3 is further dispersed.

[0097] Further, the so-called horizontal direction is a direction substantially parallel to the main surface 2a of the doctor blade 2 and substantially parallel to the axis of the doctor blade 2. In the embodiment shown in Figure 1 In the embodiment shown in FIG. 1, the horizontal direction is substantially parallel to the Z direction. The vibration in the horizontal direction is easily transmitted as a transverse wave with respect to the powder 3 (a wave from the vibration direction in which the doctor blade 2 rubs against the powder 3). In addition, the so-called axis of the doctor blade 2 means a direction substantially parallel to the long side direction of the doctor blade 2.

[0098] Further, the so-called face direction is a direction that is substantially parallel to the main face 2a of the doctor blade 2 and is perpendicular to the axis of the doctor blade 2. In the embodiment shown, the face direction is substantially parallel to the Y direction. The vibration in the face direction easily transmits a transverse wave (a wave from the doctor blade 2 in a direction that vibrates by mutual friction with respect to the powder 3) with respect to the powder 3. Figure 1 In the embodiment shown, the face direction is substantially parallel to the Y direction. The vibration in the face direction easily transmits a transverse wave (a wave from the doctor blade 2 in a direction that vibrates by mutual friction with respect to the powder 3) with respect to the powder 3.

[0099] The horizontal direction and the face direction components of the high frequency vibration of the doctor blade 2 in the vicinity of the ultrasonic wave band contribute to a decrease in the frictional resistance between the powder 3, and also greatly contribute to a decrease in the frictional force between the doctor blade 2 and the powder 3. If the vertical direction vibration component is excessively increased, the vibration can be excessively transmitted, the powder 3 can greatly vibrate, and the film thickness deviation can become large. However, the horizontal direction vibration component can particularly improve the flowability of the powder 3 because it also enables a decrease in the frictional force between the doctor blade 2 and the powder 3. In addition, the horizontal direction vibration of the doctor blade 2 can be achieved by mounting a high frequency transducer in the axial direction of the doctor blade 2 and connecting the end portions of the doctor blade 2 by a bearing, and thus the device configuration can be simplified with respect to the vibration in the face direction.

[0100] The direction of the high frequency vibration of the doctor blade 2 in the vicinity of the ultrasonic wave band can be only the vertical direction, only the horizontal direction, or only the face direction. However, if the high frequency vibration in the vicinity of the ultrasonic wave band of both the vertical direction and the horizontal direction is used, the flowability of the powder 3 can be further improved. In the case of focusing on a single particle of the powder 3, the vibration direction of the particle becomes random, the vibration is transmitted to the entire surface of the powder 3 on the upstream side from the doctor blade 2, and thus the face in which the vibration is not transmitted and the frictional resistance is high disappears, and the flowability is improved.

[0101] In the case where the doctor blade 2 performs high frequency vibration in the vicinity of the ultrasonic wave band in the vertical direction and the horizontal direction, the size of the horizontal direction vibration of the doctor blade 2 is preferably larger than the size of the vertical direction vibration of the doctor blade 2. That is, with respect to the doctor blade 2, the size of the vibration of the transverse wave component (a wave in a direction that vibrates by mutual friction with respect to the powder 3 from the doctor blade 2) of the powder 3 is preferably larger than the size of the vibration of the longitudinal wave component (a vibration direction that approaches or moves away from the doctor blade 2 with respect to the powder 3) of the powder 3. In this case, the frictional resistance at the interface (for example, the main face 2a and the end face 2b) of the doctor blade 2 and the powder 3 at which the frictional resistance easily becomes high can be particularly reduced by the horizontal direction vibration of the doctor blade 2, and the frictional resistance between the powder 3 can also be reduced, and thus the flowability of the powder 3 can be further improved.

[0102] The size of the vertical direction vibration of the doctor blade 2, that is, the amplitude of the vertical direction of the doctor blade 2 is preferably 2 μm or more. In this case, the frictional resistance between the powder 3 can be sufficiently decreased, and the flowability of the powder 3 can be further improved.

[0103] The magnitude of the vibration in the horizontal direction of the doctor blade 2 is preferably 4 μm or more. That is, the amplitude in the horizontal direction of the doctor blade 2 is preferably 4 μm or more. In this case, the frictional resistance at the interface between the doctor blade 2 and the powder 3 can be sufficiently reduced, and the flowability of the powder 3 can be further improved.

[0104] (Slope angle of doctor blade)

[0105] Reference Figures 3A-3F The slope angle of the doctor blades 22a to 22c will be described in detail. The doctor blades 22a to 22c are one example of the doctor blade 2. Figure 3B Figure 3D Figure 3F A repose angle model of the powder 3 is illustrated. The so-called repose angle A is an angle formed by a slope of a mountain of the powder 3 and a horizontal plane when the powder 3 is spontaneously kept stable in a mountain shape without being scattered when the powder 3 is dropped from a certain height to a sheet. The powder 3 flows in the direction of the hollow arrow, and thus the start point of the arrow is considered as the upper side (upstream side) of the repose angle model of the powder 3. Thus, as illustrated in Figure 3B Figure 3D Figure 3F As illustrated by the double-dot chain line, the state in which the powder 3 is kept stable in a mountain shape is represented by rotating 90°. The slope is indicated by a tangent line of the double-dot chain line, and the horizontal plane is indicated by the main surface 22al of the doctor blade 22a. In addition, only Figure 3B is illustrated with respect to the repose angle A, but the same is true in Figure 3D and Figure 3F , and the illustration is omitted. In addition, in Figures 3A-3F , the illustration of the sheet is omitted.

[0106] Figure 3A Figure 3B An angle θ of the main surface 22al of the doctor blade 22a with respect to the longitudinal direction is 0°. The so-called longitudinal direction means a direction perpendicular to the sheet 4 as a member (also referred to as a vertical direction of the member). The main surface 22al of the doctor blade 22a is a surface among the outer circumferential surfaces of the doctor blade 22a that makes the thickness of the powder 3 uniform.

[0107] In this case, as illustrated in Figure 3A and Figure 3B , in a case where the repose angle of the powder 3 is A, the powder 3 that reaches the main surface 22al of the doctor blade 22a becomes difficult to be scattered, and the stagnation of the powder 3 is easily generated. However, since the doctor blade 22a vibrates at a high frequency in the vicinity of the ultrasonic wave band, even if the angle θ of the main surface 22al of the doctor blade 22a with respect to the longitudinal direction is 0°, the flowability of the particles is improved by transmitting the vibration to the powder 3, and thus the stagnation of the powder 3 can be reduced.

[0108] As illustrated in Figure 3C and​​​​​Figure 3D As shown, the angle θ of the main face 22b1 of the blade 22b with respect to the longitudinal direction is preferably greater than 0°. That is, the angle θ of the main face 22b1 of the blade 22b with respect to the vertical direction of the sheet 4 with which the powder 3 comes into contact is preferably greater than 0°. In Figure 3C Also Figure 3D In the above and In the above and

[0109] As shown in Figure 3E Also Figure 3F As shown, the angle θ of the main face 22c1 of the blade 22c with respect to the longitudinal direction is particularly preferably the angle of repose A of the powder 3 or more. That is, the angle θ of the main face 22c1 of the blade 22c with respect to the vertical direction of the sheet 4 is particularly preferably substantially the same as the angle of repose A of the powder 3. In Figure 3E Also Figure 3F In the above and In the above and

[0110] Hereinafter, Modification Examples 1 and 2 of the structure of the blade will be described.

[0111] (Modification Example 1)

[0112] In the present modification example, the blade will be described. In the present modification example, the different point from Embodiment 1 is that the shape of the blade is a circular shape in a side view. As for other structures in the present modification example, the same as Embodiment 1, the same reference numerals are attached to the same structures, and detailed description on the structures will be omitted.

[0113] In the present modification example, as shown in Figure 4 The blade 102 has a curved surface 2c, and has a shape in which the main face 2a extends from the end face toward the upstream side in the moving direction of the sheet 4. However, the shape of the blade 102 is not limited thereto. The blade 102 can be a shape in which the thickness of the powder 3 can be adjusted, and can be, for example, an elliptical shape, or the main face 2a of Embodiment 1 can be a semicircular shape only.

[0114] In the above and Figure 4Other shapes of the scraper 102 are described. The scraper 102, as shown in FIG. 1, can also be cylindrical. Specifically, it is preferable that the scraper 102 be substantially parallel to the surface 4a of the sheet 4 and be a curved surface 2c and an axis substantially parallel cylindrical shape. Figure 4

[0115] When the powder 3 advances and comes into contact with the surface of the scraper 102, pressure is generated on the powder 3. As a result, the powder 3 easily stagnates / agglomerates, thereby causing powder clogging. By the scraper 102 being cylindrical, the angle of contact of the powder 3 with the scraper 102 continuously increases, eventually becoming an angle of repose or more. As a result, the pressure generated on the powder 3 is gradually eased without having a particular point, eventually becoming an angle of repose or more, thereby being released. Therefore, in the case where the scraper 102 is cylindrical, the powder 3 becomes less likely to stagnate / agglomerate.

[0116] In the case where the scraper 102 is cylindrical, the direction of high frequency vibration in the vicinity of the ultrasonic wave band of the scraper 102 includes at least one of a horizontal direction component and a vertical direction component. That is, the scraper 102 vibrates in at least one of the horizontal direction and the vertical direction.

[0117] In the case where the scraper 102 is cylindrical, the so-called horizontal direction is a direction substantially parallel to the main surface 2a of the scraper 102. In the present modification, the vibration in the horizontal direction easily transmits a transverse wave (a wave from the direction in which the scraper 102 vibrates with respect to the powder 3) with respect to the powder 3.

[0118] In the case where the scraper 102 is cylindrical, the so-called vertical direction is a direction perpendicular to the main surface 2a of the scraper 102. That is, a direction perpendicular to the circumference of the scraper 102. The vibration in the vertical direction easily transmits a longitudinal wave (a wave from the direction in which the scraper 102 approaches or moves away from the powder 3) with respect to the powder 3.

[0119] The cylindrical scraper 102, for example, can also be fixed by a support with a bearing at both ends of the scraper 102 so as to slide in the horizontal direction. In this case, it is possible to establish a relationship of (horizontal direction amplitude) > (vertical direction amplitude) by making the axis of the scraper 102 a shape that fits into the caliber of the circular bearing.

[0120] In the case where the scraper 102 is cylindrical, the diameter of the cylinder is preferably 4 mm or more and 300 mm or less. By being 4 mm or more, the change in angle does not easily become sharp, and the effect of continuously releasing pressure easily becomes large. By being 300 mm or less, the weight of the scraper 102 does not become too heavy, the scraper 102 easily follows the motion of the high frequency vibration in the vicinity of the ultrasonic wave band, and a sufficient vibration effect can be obtained.

[0121] (Modification 2)​

[0122] In the present modification, the doctor blades 102, 103 are described. In the present modification, the point of difference from Embodiment 1 is that the doctor blades 102, 103 are multi-stage. As for other structures in the present modification, in the case where no particular description is given, the same structures as in Embodiment 1 are denoted by the same reference numerals, and detailed description related to the structures is omitted.

[0123] Using Figure 5 Another manner of the doctor blades 102, 103 is described.

[0124] The ratio of the thickness of the powder 3 before the thickness adjustment by the doctor blades 102, 103 to the thickness of the powder 3 after the thickness adjustment by the doctor blades 102, 103 is preferably in the range of 1:1 to 3:1. In the present modification, since the ratio of the thickness of the powder before the doctor blade 103 to the thickness of the powder 3 after the doctor blade 102 is less than 3, the amount of the powder 3 located in front of the doctor blade 102 does not become excessive, and the pressure received by the powder 3 from the main surfaces 102a, 103a of the doctor blades 102, 103 easily becomes small. Thus, the powder 3 is less likely to be retained or agglomerated, and powder clogging can be more suppressed. Further, since the ratio of the thickness of the powder before the doctor blade 103 to the thickness of the powder 3 after the doctor blade 103 and the ratio of the thickness of the powder before the doctor blade 102 to the thickness of the powder 3 after the doctor blade 102 are greater than 1, the powder 3 can be flattened well by the doctor blades 102, 103.

[0125] In addition, the doctor blade 103 that adjusts the film thickness of the powder 3 before the doctor blade 102 in advance can be provided so that the ratio of the thickness of the powder 3 before the thickness adjustment by the doctor blade 102 to the thickness of the powder 3 after the thickness adjustment becomes the above range.

[0126] In addition, the film thickness of the powder 3 before the doctor blade 103 can be adjusted in advance so that the ratio of the thickness of the powder 3 before the thickness adjustment by the doctor blade 103 to the thickness of the powder 3 after the thickness adjustment becomes the above range.

[0127] The doctor blade 103 is disposed at a position that is more downstream in the moving direction of the powder 3 than the powder supply part 11 (hopper) and is more upstream in the moving direction of the powder 3 than the doctor blade 2 so that a given gap between the doctor blade 102 and the surface 4a is formed between the doctor blade 103 and the surface 4a. In this way, the powder coating apparatus 1 can have a multi-stage doctor blade including a plurality of doctor blades 102, 103. In this case, the adjustment of the thickness of the powder 3 can be performed in stages, and thus the powder 3 is less likely to be retained or agglomerated, and powder clogging can be more suppressed. Such a multi-stage doctor blade configuration is useful for a powder having particularly low flowability. In addition, as described above, the doctor blade 103 can be disposed at a position that is more downstream in the moving direction of the powder 3 than the powder supply part 11 (hopper) and is more upstream in the moving direction of the powder 3 than the doctor blade 2 so that a given gap between the doctor blade 102 and the surface 4a is formed between the doctor blade 103 and the surface 4a. Figure 5As shown, the multi-stage doctor blade can include two doctor blades, the doctor blade 103 and the doctor blade 102, or three or more doctor blades.

[0128] The following returns to the description of the embodiments.

[0129] [Method for manufacturing energy device]

[0130] The following refers to Figure 1 and Figure 6 A method for manufacturing an energy device as one embodiment of the method for manufacturing an energy device related to the present disclosure will be described. In the method for manufacturing an energy device, an energy device can be manufactured using a powder coating device 1 as shown in Figure 1

[0131] As shown in Figure 1 and Figure 6 The method for manufacturing an energy device includes, as shown in the drawing, moving a sheet 4 for an energy device such as a current collector along a given direction while supplying a powder 3 to the surface of the sheet 4 (powder supply step S10), and adjusting the thickness of the powder 3 supplied to the surface of the sheet 4 using a doctor blade 2 (powder arrangement step S20).

[0132] First, in the method for manufacturing an energy device, a powder 3 is prepared. The raw material of the powder 3 is not particularly limited, and for example, a particle group containing an active material can be used. A substance to which a suitable additive (for example, a conductive material) is added to an active material and a binder is mixed to prepare the powder 3. As a method of mixing, for example, there is a method of mixing by a mortar, a ball mill, a stirrer, or the like. In particular, a method of mixing the powder 3 without using a solvent or the like is preferable because there is no material degradation.

[0133] In the powder supply step S10, the powder 3 is supplied to the surface of the sheet 4 using a powder supply part 11 such as a hopper while moving the sheet 4 along a given direction. The sheet 4 can be in a sheet shape.

[0134] The powder arrangement step S20 is a step of arranging the powder 3 on the surface 4a of the sheet 4 using the doctor blade 2 of the powder coating device 1. That is, in the powder arrangement step S20, the thickness of the powder 3 supplied to the surface 4a of the sheet 4 is adjusted to be flat using the doctor blade 2. At this time, the doctor blade 2 vibrates at a frequency of 2 kHz or more and 300 kHz or less.

[0135] The method for manufacturing an energy device further has a powder sheeting step S30. The powder sheeting step S30 is a step of compressing the powder 3 arranged on the sheet 4 using a roll press 6 of the powder coating device 1. Thus, a compressed powder layer 5 in which the powder 3 is compressed is formed on the surface 4a of the sheet 4.

[0136] ​As above, in the energy device manufacturing method, the compressed powder layer 5 containing the powder 3 is formed on the surface 4a of the sheet 4 by sequentially performing the powder supply process S10, the powder arrangement process S20, and the powder sheeting process S30. Such a laminate of the sheet 4 and the compressed powder layer 5 can be used for an energy device. For example, in a case where a current collector is used as the sheet 4 and an active material is used as the powder 3, an electrode for an energy device can be manufactured.

[0137] The energy device manufactured using the powder coating device 1 can have a compressed powder layer 5 with less variation in thickness even if a powder 3 with low flowability is used. Therefore, according to the energy device manufacturing method, it is not necessary to perform a granulation process for making the flowability of the powder 3 good, and thus it is possible to prevent deterioration of materials and to suppress an increase in cost. In addition, since the thickness of the compressed powder layer 5 is uniform, it is possible to improve the characteristics as an electrode in an energy device, and to manufacture an energy device with good quality (output, etc.) at low cost.

[0138] [Positive electrode and negative electrode for battery]

[0139] Hereinafter, one embodiment of a positive electrode and a negative electrode for a battery to which the present disclosure is applied will be described with reference to Figure 7 and Figure 8 . Figure 7 is a cross-sectional view of a positive electrode of an all-solid-state battery to which one embodiment of the present disclosure is applied. Figure 8 is a cross-sectional view of a negative electrode of an all-solid-state battery to which one embodiment of the present disclosure is applied. The positive electrode and the negative electrode of the present embodiment can be used in an all-solid-state battery, for example.

[0140] As shown in Figure 7 and Figure 8 , an all-solid-state battery includes a pair of electrodes including a positive electrode and a negative electrode, and a solid electrolyte layer disposed between the pair of electrodes, for example. The positive electrode includes a positive electrode current collector 54 and a positive electrode mixture layer 53. The negative electrode includes a negative electrode current collector 64 and a negative electrode mixture layer 63. The positive electrode mixture layer 53 and the negative electrode mixture layer 63 can be manufactured using the powder coating device 1 described above. The negative electrode will be described later. The positive electrode is one example of a positive electrode layer or the positive electrode mixture layer 53. In addition, the negative electrode is one example of a negative electrode layer or the negative electrode mixture layer 63 described later.

[0141] As shown in Figure 7 , the positive electrode mixture layer 53 is formed on the positive electrode current collector 54 and contains a positive electrode active material 51 and a solid electrolyte 52 having ion conductivity. The positive electrode mixture layer 53 and the positive electrode current collector 54 constitute the positive electrode.

[0142] The concentration of the solvent contained in the positive electrode mixture layer 53 is 50 ppm or less. That is, the positive electrode mixture layer 53 substantially does not contain a solvent. By the term "substantially does not contain", it means a case where it does not contain at all, and a case where it is inevitably contained as an impurity or the like in 50 ppm or less. In addition, by the term "solvent", it means an organic solvent. The measurement method of the solvent is not particularly limited, and for example, it can be measured using a gas chromatograph and a mass change method or the like. Examples of the organic solvent include: non-polar 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 ethane thiol. Examples of the ester-based solvent include butyl butyrate, ethyl acetate, and butyl acetate.

[0143] The area of the positive electrode mixture layer 53 is 900 mm 2 The thickness of the positive electrode mixture layer 53 is 15 μm or more.

[0144] The thickness Tp of the positive electrode mixture layer 53 has a deviation of ±5% or less. That is, in a case where the average film thickness of the positive electrode mixture layer 53 is set to Tp, the minimum value and the maximum value of the film thickness of the positive electrode mixture layer 53 are within a range of Tp ± 5%.

[0145] The positive electrode mixture layer 53 is produced using the powder coating device 1, and thus even if it is produced using a powder 3 (positive electrode active material 51 and solid electrolyte powder having an average particle diameter of 50 μm or less) having low fluidity, the thickness of the positive electrode mixture layer 53 as a compressed powder layer 5 has a small deviation, and it is easy to form a uniform thickness. Further, by using the powder coating device 1, it is possible to produce a large-scale high-capacity positive electrode mixture layer 53 having an area of 900 mm 2 The thickness of the positive electrode mixture layer 53 is 15 μm or more, and is large-scale and high-capacity. In addition, the positive electrode mixture layer 53 is produced by a coating process in which a solvent is not contained, and thus there is no damage caused by a solvent. Therefore, the positive electrode of the all-solid-state battery can obtain a large-scale / high-capacity positive electrode mixture layer 53 having a small deviation in film thickness and high output.

[0146] In addition, the average particle diameter (D50) of the positive electrode active material 51 is preferably 50 μm or less. By using an active material having a small particle diameter, the surface area becomes large, and it is possible to set a high capacity.

[0147] In addition, it is preferable that the solid electrolyte 52 in the positive electrode mixture layer 53 maintains a good dispersion state. In a case where the cross section of the positive electrode mixture layer 53 is observed, it is more preferable that the cross-sectional area is 100 μm 2The total area of the agglomerated portions of the solid electrolyte 52 is 2% or less relative to the cross-sectional area of the positive electrode mixture layer 53. In this case, by dispersing the solid electrolyte 52 well in the positive electrode mixture layer 53, the solid electrolyte 52 can be flexibly used without waste, and a positive electrode mixture layer 53 having a high capacity characteristic can be obtained.

[0148] The powder 3 containing the solid electrolyte 52 can be flattened by applying high-frequency vibration in the vicinity of the ultrasonic wave band to the doctor blade 2, thereby improving the dispersibility of the solid electrolyte 52. By the high-frequency vibration in the vicinity of the ultrasonic wave band, the powder 3 is vibrated and flows at the portion where the powder 3 is aggregated on the upstream side of the doctor blade 2. Thus, the powder 3 is mixed with each other, and the solid electrolyte 52 in the powder 3 is well dispersed.

[0149] The positive electrode active material 51 is a material in which metal ions such as lithium (Li) are inserted into or detached from a crystal structure at a higher potential than a negative electrode, and oxidation or reduction is performed with the insertion or detachment of the metal ions such as lithium. The kind of the positive electrode active material 51 is appropriately selected depending on the kind of the all-solid-state battery, and for example, an oxide active material, a sulfide active material, or the like can be given.

[0150] The positive electrode active material 51 in the present embodiment uses, for example, an oxide active material (a lithium-containing transition metal oxide). As the oxide active material, for example, LiCoO2, LiNiO2, LiMn2O4, LiCoPO4, LiNiPO4, LiFePO4, LiMnPO4, a compound obtained by substituting the transition metal of these compounds with one or two different kinds of elements, or the like can be given. As the compound obtained by substituting the transition metal of the above-described compound with one or two different kinds of elements, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, LiNi 0.8 Co 0.15 Al 0.05 O2, LiNi 0.5 Mn 1.5 O2, or the like can be used. The positive electrode active material 51 can be used as one kind, or two or more kinds can be combined and used.

[0151] As the positive electrode active material 51, for example, a particle shape and a thin film shape, and the like can be cited. In the case where the positive electrode active material 51 is in a particle shape, the average particle diameter (D50) of the positive electrode active material 51 is preferably, for example, in a range of 50 nm or more and 50 μm or less, and more preferably in a range of 1 μm or more and 15 μm or less. By setting the average particle diameter of the positive electrode active material 51 to 50 nm or more, the operability easily becomes excellent, and on the other hand, by setting the average particle diameter to 50 μm or less, a high-capacity positive electrode is easily obtained, and thus the range is preferable. In addition, the "average particle diameter" in the present specification is an average diameter on a volume basis measured by a laser analysis and a scattering type particle size distribution measuring device.

[0152] The content of the positive electrode active material 51 in the positive electrode mixture layer 53 is not particularly limited, but is preferably, for example, in a range of 40% by mass or more and 99% by mass or less, and is more preferably in a range of 70% by mass or more and 95% by mass or less.

[0153] The surface of the positive electrode active material 51 can also be coated with a coating layer. This is because the reaction of the positive electrode active material 51 (for example, an oxide active material) and the solid electrolyte 52 (for example, a sulfide-based solid electrolyte) can be inhibited. As a material of the coating layer, for example, a Li ion-conductive oxide such as LiNb03, Li3P04, LiPON, and the like can be cited. The average thickness of the coating layer is preferably, for example, in a range of 1 nm or more and 20 nm or less, and more preferably in a range of 1 nm or more and 10 nm or less.

[0154] In the case where the ratio of the positive electrode active material 51 to the solid electrolyte 52 included in the positive electrode mixture layer 53 is set to (positive electrode active material) / (solid electrolyte) = weight ratio by weight conversion, the weight ratio is preferably in a range of 1 or more and 19 or less, and more preferably in a range of 2.3 or more and 19 or less. As a reason why the weight ratio is preferably in this range, both of a lithium ion conduction path and an electron conduction path in the positive electrode mixture layer 53 are easily ensured.

[0155] The solid electrolyte 52 is appropriately selected depending on the type of a conduction ion (for example, lithium ion), and for example, can be broadly classified into a sulfide-based solid electrolyte and an oxide-based solid electrolyte.

[0156] The kind of the sulfide-based solid electrolyte in the present embodiment is not particularly limited, and as the sulfide-based solid electrolyte, for example, Li2S-SiS2, LiI-Li2S-SiS2, LiI-Li2S-P2S5, LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, and Li2S-P2S5, and the like can be given, and particularly, since the lithium ion conductivity is excellent, it is preferable to contain Li, P, and S. The sulfide-based solid electrolyte can be used as one kind, or two or more kinds in combination. In addition, the sulfide-based solid electrolyte can be crystalline, or amorphous, or glass-ceramic. In addition, the above description of "Li2S-P2S5" means a sulfide-based solid electrolyte formed using raw material components containing Li2S and P2S5, and the same applies to other descriptions.

[0157] In the present embodiment, one mode of the sulfide-based solid electrolyte is a sulfide glass-ceramic containing Li2S and P2S5, and in the case where the ratio of Li2S and P2S5 is set to Li2S / P2S5 = molar ratio by molar conversion, the molar ratio is preferably in the range of 2.3 or more and 4 or less, and more preferably in the range of 3 or more and 4 or less. The reason why the molar ratio is preferably in this range is because it is possible to set a crystal structure with high ion conductivity while maintaining the lithium concentration that affects the battery characteristics.

[0158] As the shape of the sulfide-based solid electrolyte in the present embodiment, for example, a particle shape such as a spherical shape, an ellipsoidal shape, and the like, a film shape, and the like can be given. In the case where the sulfide-based solid electrolyte material is in a particle shape, the average particle diameter (D50) of the sulfide-based solid electrolyte is not particularly limited, but since it is easy to increase the filling rate in the positive electrode, it is preferably 40 μm or less, more preferably 50 μm or less, and further preferably 10 μm or less. On the other hand, the average particle diameter of the sulfide-based solid electrolyte is preferably 0.001 μm or more, and more preferably 0.01 μm or more. In addition, the average particle diameter can be determined, for example, by using a particle size distribution meter, image analysis of SEM (Scanning Electron Microscope).

[0159] Next, the oxide-based solid electrolyte in the present embodiment will be described. The kind of the oxide-based solid electrolyte is not particularly limited, but for example, LiPON, Li3PO4, Li2SiO2, Li2SiO4, Li 0.5 La 0.5 TiO3, Li 1.3 Al 0.3 Ti 0.7 (PO4)3, La 0.51 Li 0.34 TiO0.74 Li 1.5 Al 0.5 Ge 1.5 (PO4)3, etc. Oxide-based solid electrolytes can be used in combination with one or more types.

[0160] The all-solid-state battery in this embodiment includes, for example, a positive electrode current collector 54 comprising a metal foil. The positive electrode current collector 54 may be a foil, plate, or mesh containing aluminum, gold, platinum, zinc, copper, SUS, nickel, tin, titanium, or two or more alloys thereof.

[0161] Furthermore, the thickness and shape of the positive current collector 54 can be appropriately selected according to the application of the all-solid-state battery.

[0162] Next, refer to Figure 8 Explain the negative electrode.

[0163] like Figure 8 As shown, a negative electrode mixture layer 63 is formed on the negative electrode current collector 64, containing a negative electrode active material 61 and a solid electrolyte 52 with ion conductivity. The negative electrode mixture layer 63 and the negative electrode current collector 64 constitute the negative electrode.

[0164] The concentration of the solvent contained in the negative electrode mixture layer 63 is 50 ppm or less. That is, the negative electrode mixture layer 63 substantially does not contain any solvent. "Substantially does not contain" means either completely absent or inevitably contained at a concentration of 50 ppm or less as an impurity. Furthermore, "solvent" refers to an organic solvent, and examples of solvents contained in the negative electrode mixture layer 63 are the same as those exemplified as solvents contained in the positive electrode mixture layer 53. The method for determining the solvent is not particularly limited; for example, it can be determined using gas chromatography or mass change analysis.

[0165] The area of ​​the negative electrode mixture layer 63 is 900 mm². 2 The thickness of the negative electrode mixture layer 63 is 15 μm or more.

[0166] The thickness Tn of the negative electrode mixture layer 63 has a deviation of less than ±10%. That is, when the average film thickness of the negative electrode mixture layer 63 is set to Tn, the minimum and maximum film thickness of the negative electrode mixture layer 63 are within the range of Tn ±10%.

[0167] Since the negative electrode mixture layer 63 is produced using the powder coating device 1, even if the negative electrode mixture layer 63 is produced using a powder 3 having low fluidity (a negative electrode active material 61 and a solid electrolyte powder each having an average particle diameter of 50 μm or less), the thickness of the negative electrode mixture layer 63 as the compressed powder layer 5 is less likely to vary, and is easily formed with a uniform thickness. Further, by using the powder coating device 1, a large-scale high-capacity negative electrode mixture layer 63 having an area of 900 mm 2 above and a thickness of 15 μm or more can be produced. Moreover, since the negative electrode mixture layer 63 is produced by a coating process that does not involve a solvent, there is no damage caused by the solvent. Thus, the negative electrode of the all-solid-state battery can obtain a large-scale / high-capacity negative electrode mixture layer 63 having a small variation in film thickness and high output.

[0168] In addition, the average particle diameter (D50) of the negative electrode active material 61 is preferably 50 μm or less. By using an active material having a small particle diameter, the surface area becomes large, and a high capacity can be achieved.

[0169] The negative electrode active material 61 is a material in which a metal ion such as lithium is inserted into or detached from a crystal structure at a lower potential than that of the positive electrode, and oxidation or reduction occurs with the insertion or detachment of the metal ion such as lithium.

[0170] As the negative electrode active material 61 in the present embodiment, for example, an alloying metal such as lithium, indium, tin, silicon, a carbon material such as hard carbon, graphite, and the like, and a known material such as an oxide active material of Li4Ti5O 12 , SiO x , and the like can be used. In addition, as the negative electrode active material 61, a composite obtained by appropriately mixing the above-described negative electrode active material 61 and the like can also be used.

[0171] In a case where the ratio of the negative electrode active material 61 to the solid electrolyte 52 included in the negative electrode mixture layer 63 is set to a negative electrode active material / solid electrolyte = weight ratio by weight conversion, the weight ratio is preferably in a range of 0.6 or more and 19 or less, and more preferably in a range of 1 or more and 5.7 or less. As a reason why the weight ratio is preferably in the range, both of a lithium ion conduction path and an electron conduction path in the negative electrode mixture layer 63 can be ensured.

[0172] The negative electrode in the present embodiment, for example, has a negative electrode current collector 64 including a metal foil or the like. In the negative electrode current collector 64, for example, a foil-shaped body, a plate-shaped body, a mesh-shaped body, or the like including SUS, gold, platinum, zinc, copper, nickel, titanium, tin, or an alloy of two or more of them, or the like can be used.

[0173] In addition, the thickness and the shape of the negative electrode current collector 64 and the like can also be appropriately selected depending on the use of the all-solid-state battery.

[0174] (Example 1)

[0175] The present disclosure will now be specifically described through Example 1. However, the present disclosure is not limited to Example 1.

[0176] For Example 1 and Comparative Example 1, the scraper was cylindrical, and powder with an angle of repose of 45° and an average particle size of 1.5 μm was used in the experiment. The deviation of the powder film thickness after passing through the scraper was compared. The results are shown below. Figure 10 The so-called Figure 10 The vibration frequency in the text refers to the vibration frequency of the scraper. The so-called powder film thickness deviation is the ratio of the standard deviation of the powder film thickness (3 times) to the powder film thickness.

[0177] (Example 2)

[0178] The present disclosure will now be specifically described through Example 2. However, the present disclosure is not limited to the following examples.

[0179] For Examples 2-5 and Comparative Examples 2-4, the scraper was a flat plate shape. Simulations were performed using powder with a resting angle of 46° and an average particle size of 10 μm, and the retained particle ratio was analyzed. The vibration frequency of the scraper was 2.5 kHz. The results are shown below. Figure 11 The so-called Figure 11 The angle in the equation is the angle formed by the direction perpendicular to the sheet material transporting the powder and the main surface of the scraper. In Examples 2-5, the side with a lower powder retention ratio can achieve a stable coating film. The powder retention ratio is the proportion of powder retained due to the scraper, which is the ratio of the number of powder particles at a speed of 15% or less of the powder transport speed to the total number of powder particles. If the powder retention ratio is high, it will induce powder blockage in the scraper and cause film thickness deviation in the powder coating.

[0180] Industrial availability

[0181] The powder coating apparatus disclosed herein can produce powder layers with minimal and uniform thickness deviations without solvents, and therefore can also be applied to applications such as the mixing layer of high-quality all-solid-state batteries.

Claims

1. A powder coating apparatus comprising: a driving section configured to move a member in a given direction; a powder supply section configured to supply a powder to a surface of the member; and a doctor blade configured to adjust a thickness of the powder supplied to the surface of the member by the powder supply section, wherein the doctor blade is vibrated at a frequency of 2 kHz or more and 300 kHz or less, the doctor blade is vibrated in a horizontal direction parallel to a main surface of the doctor blade and parallel to a long side direction of the doctor blade and in a vertical direction perpendicular to the main surface of the doctor blade, and a magnitude of the vibration in the horizontal direction is greater than a magnitude of the vibration in the vertical direction.

2. The powder coating apparatus according to claim 1, wherein an average particle diameter D50 of the powder is 0.005 μm or more and 50 μm or less.

3. The powder coating apparatus according to claim 1 or 2, wherein an angle formed by a main surface of the doctor blade in contact with the powder with respect to the vertical direction of the surface of the member is greater than 0°.

4. The powder coating apparatus according to claim 3, wherein the angle is equal to or greater than a repose angle of the powder.

5. The powder coating apparatus according to claim 1 or 2, wherein the doctor blade is formed in a cylindrical shape having an axis parallel to the surface of the member and orthogonal to a moving direction of the surface of the member.

6. The powder coating apparatus according to claim 1 or 2, wherein a ratio of a thickness of the powder before thickness adjustment by the doctor blade to a thickness of the powder after thickness adjustment by the doctor blade is in a range of 1:1 to 3:

1.

7. The powder coating apparatus according to claim 1 or 2, further comprising a pressing section configured to compress the powder on the member whose thickness is adjusted by the doctor blade.

8. A method for manufacturing an energy device, comprising: supplying a powder to a surface of a member while moving the member in a given direction; and adjusting a thickness of the powder supplied to the surface using a doctor blade, wherein the doctor blade is configured to form a gap between the member and the doctor blade, the doctor blade is vibrated at a frequency of 2 kHz or more and 300 kHz or less, the doctor blade is vibrated in a horizontal direction parallel to a main surface of the doctor blade and parallel to a long side direction of the doctor blade and in a vertical direction perpendicular to the main surface of the doctor blade, and a magnitude of the vibration in the horizontal direction is greater than a magnitude of the vibration in the vertical direction.

9. A positive electrode for a battery comprising: a positive electrode current collector; and a positive electrode layer containing a positive electrode active material and formed on the positive electrode current collector, wherein the positive electrode layer is produced using the powder coating apparatus according to any one of claims 1 to 7, a concentration of a solvent contained in the positive electrode layer is 50 ppm or less, a thickness of the positive electrode layer is 15 μm or more, and a deviation of the thickness of the positive electrode layer is ±5% or less.

10. The positive electrode for a battery according to claim 9, wherein the positive electrode layer includes a positive electrode mixture layer containing the positive electrode active material and a solid electrolyte having ion conductivity and formed on the positive electrode current collector. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The area of the positive electrode layer is 900 mm 2 The above, ​ ​ ​ ​ a concentration of a solvent contained in the positive electrode mixture layer is 50 ppm or less, The area of the positive electrode mixture layer is 900 mm 2 The above, a thickness of the positive electrode mixture layer is 15 μm or more, a deviation of the thickness of the positive electrode mixture layer is ± 5% or less.

11. The positive electrode for a battery according to claim 10, wherein cross-sectional area of 100 μm 2 The total area of the agglomerated portions of the solid electrolyte in the positive electrode mixture layer is 2% or less relative to the cross-sectional area of the positive electrode mixture layer.

12. A negative electrode for a battery, comprising: a negative electrode current collector; and a negative electrode layer containing a negative electrode active material and formed on the negative electrode current collector, the negative electrode layer is produced using the powder coating device according to any one of claims 1 to 7, a concentration of a solvent contained in the negative electrode layer is 50 ppm or less, The area of the negative electrode layer is 900 mm 2 The above, a thickness of the negative electrode layer is 15 μm or more, a deviation of the thickness of the negative electrode layer is ± 10% or less.

13. The negative electrode for a battery according to claim 12, wherein the negative electrode layer comprises a negative electrode mixture layer containing the negative electrode active material and a solid electrolyte having ion conductivity and formed on the negative electrode current collector, a concentration of a solvent contained in the negative electrode mixture layer is 50 ppm or less, The area of the negative electrode mixture layer is 900 mm 2 The above, a thickness of the negative electrode mixture layer is 15 μm or more, a deviation of the thickness of the negative electrode mixture layer is ± 10% or less.

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