Molding device

Abstract

To compress a powder used as a battery material properly.SOLUTION: A molding device 1 includes: a cylindrical member 10 in which a bottom part is filled with a powder which is a battery material of an all-solid-state battery; a compression member 20 which moves toward the bottom part along an inner peripheral surface 11 of the cylindrical member 10 and compresses a layer of the powder; and a cylindrical guide part 30 which is provided at an upper part of the cylindrical member 10 so as to protrude toward a center in a radial direction of the cylindrical member 10 farther than the inner peripheral surface 11 and slidably guides the compression member 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a molding apparatus for an all-solid-state battery. [Background technology]

[0002] The positive electrode layer, negative electrode layer, and solid electrolyte layer of an all-solid-state battery are each formed by pressing powder, which is the battery material (see Patent Document 1 below). Specifically, the powder is filled into the bottom of a cylindrical member, and the powder layer is pressed by a pressing member that slides against the cylindrical member, thereby forming the positive electrode layer, etc. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-61434 Summary of the Invention [Problem to be solved by the invention]

[0004] However, some of the filled powder floats inside the cylindrical member, and if the powder adheres to the pressure member, it may cause poor sliding of the pressure member against the cylindrical member. To prevent this, a large clearance is provided between the pressure member and the inner surface of the cylindrical member. However, if the clearance is set too large, the pressure member may slide obliquely against the cylindrical member, preventing the pressure member from properly pressing the powder layer. Specifically, part of the powder layer may not be pressed, or part of the powder layer may be pressed excessively.

[0005] The present invention has been made in view of these points, and has as its object to appropriately pressurize powder, which is a battery material. [Means for solving the problem]

[0006] In one aspect of the present invention, there is provided a molding device including: a cylindrical member whose bottom is filled with a powder that is a battery material for an all-solid-state battery; a pressure member that moves along an inner circumferential surface of the cylindrical member toward the bottom and applies pressure to a layer of the powder; and a cylindrical guide portion that is provided on an upper portion of the cylindrical member so as to protrude further toward the radial center of the cylindrical member than the inner circumferential surface and that slidably guides the pressure member.

[0007] The axial length of the guide portion may be smaller than the axial length of the cylindrical member.

[0008] Furthermore, a sliding surface of the guide portion on which the pressure member slides may have grooves formed in a grid pattern along the circumferential direction.

[0009] The groove may be formed over the entire circumferential direction of the sliding surface.

[0010] Furthermore, a recess capable of collecting the powder floating inside the cylindrical member may be formed along the circumferential direction on a sliding surface of the guide portion on which the pressing member slides.

[0011] The recessed portions may be formed at both axial ends of the guide portion.

[0012] The pressing member may pressurize the powder layer immediately after the powder is filled into the bottom portion.

[0013] In addition, after the first powder is filled into the cylindrical member, a second powder different from the first powder may be filled, and the pressure member may pressurize the layer of the first powder and the layer of the second powder. [Effects of the Invention]

[0014] According to the present invention, it is possible to appropriately pressurize the powder that is the battery material. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a schematic diagram showing a general configuration of a molding device 1 according to one embodiment. [Figure 2] FIG. 2 is a schematic diagram showing the molding device 1 when powder is filled. [Figure 3] FIG. 2 is a schematic diagram of the guide portion 30 as viewed from above. [Figure 4] FIG. 10 is a schematic diagram for explaining a comparative example. [Figure 5] 3 is a schematic diagram for explaining the detailed configuration of a guide portion 30. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] <Configuration of molding equipment> Fig. 1 is a schematic diagram showing the general configuration of a molding apparatus 1 according to one embodiment. Fig. 2 is a schematic diagram showing the molding apparatus 1 when filling powder. Fig. 3 is a schematic diagram of a guide unit 30 as viewed from above.

[0017] The molding apparatus 1 is an apparatus for molding an all-solid-state battery. The all-solid-state battery is, for example, a lithium-ion battery used as a secondary battery mounted in an automobile or the like, and is composed of a positive electrode layer, a negative electrode layer, and an electrolyte layer disposed therebetween. From the viewpoints of safety of the secondary battery and increasing the energy density, a non-flammable solid electrolyte is used as the electrolyte layer, rather than a flammable electrolytic solution.

[0018] The molding device 1 compresses and compacts powder, which is the battery material, to form at least one layer (also referred to as an element for convenience of explanation) of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer of the all-solid-state battery. In other words, the molding device 1 compression-molds at least one element of the all-solid-state battery. As shown in FIG. 1 , the molding device 1 has a cylindrical member 10, a pressing member 20, and a guide portion 30.

[0019] The cylindrical member 10 contains powder, which is a battery material for an all-solid-state battery. The cylindrical member 10 has a bottom, and an opening at the top of the cylindrical member 10. The powder is filled into the cylindrical member 10 through the opening at the top. As shown in FIG. 1 , the cylindrical member 10 has a base portion 12 and a cylindrical portion 14.

[0020] The tubular portion 14 is located on the base portion 12. The tubular portion 14 has a cylindrical shape as shown in Fig. 3 here, but is not limited to this. An upper surface 13 of the base portion 12 forms the bottom of the tubular member 10.

[0021] The bottom of the cylindrical member 10 is filled with powder, which is a battery material for the all-solid-state battery. Specifically, the upper surface 13 of the base portion 12 is filled with powder, which is a collection of particles. The powder is filled to form a layer of a predetermined thickness on the upper surface 13, as shown in FIG. 1. Two powder layers are filled on the upper surface 13 of the base portion 12. As shown in FIG. 1, the two powder layers are a first layer 50, which is a layer of a first powder, and a second layer 52, which is a layer of a second powder different from the first powder. After the first powder is filled into the cylindrical member 10 to form the first layer 50, the second powder is filled into the cylindrical member 10 to form the second layer 52.

[0022] The first layer 50 here becomes the solid electrolyte layer of the all-solid-state battery by being compressed by the pressing member 20. The first layer 50 here is made of LGPS (lithium germanium phosphorus sulfur).

[0023] Here, the second layer 52 becomes the positive electrode layer of the all-solid-state battery by being compressed by the pressure member 20. The positive electrode layer of the all-solid-state battery is a layer in which a positive electrode active material and a solid electrolyte are mixed, and for example, the mass ratio of the active material is 70% and the mass ratio of the solid electrolyte is 30%. Therefore, the second layer 52 is a layer in which multiple battery materials are mixed, and specifically, lithium cobalt oxide and LGPS (lithium germanium phosphorus sulfur) are mixed.

[0024] In the above description, the powder layer on the upper surface 13 is two layers, the first layer 50 and the second layer 52, but is not limited to this. The powder layer on the upper surface 13 may be one layer or three layers. Therefore, the molding device 1 can mold each element of the all-solid-state battery or mold three elements of the all-solid-state battery together.

[0025] The pressure applying member 20 applies pressure to the first layer 50 and the second layer 52, which are layers of powder inside the cylindrical member 10. The pressure applying member 20 applies pressure to the first layer 50 and the second layer 52 at a predetermined pressure using a drive source. The pressure applying member 20 moves along the inner circumferential surface 11 of the cylindrical member 10 toward the bottom of the cylindrical member 10, and applies pressure to the first layer 50 and the second layer 52 on the upper surface 13 of the base portion 12. The pressure applying member 20 applies pressure to the first layer 50 and the second layer 52 once, thereby compacting the first layer 50 and the second layer 52.

[0026] The pressure applying member 20 is movable up and down between a standby position shown in FIG. 2 and a pressure applying position shown in FIG. 1. When the pressure applying member 20 is located at the standby position, powder is filled into the tubular member 10. When the pressure applying member 20 moves from the standby position to the pressure applying position, the pressure applying member 20 compresses the powder layer on the upper surface 13. In this embodiment, the pressure applying member 20 applies pressure to the first layer 50 and the second layer 52 on the upper surface 13. The pressure applied by the pressure applying member 20 brings the battery material particles in the first layer 50 into contact with each other, thereby forming a solid electrolyte layer. Similarly, the pressure applied by the pressure applying member 20 brings the particles in the second layer 52 into contact with each other, thereby forming a positive electrode layer.

[0027] As shown in FIG. 1, the pressure member 20 has a shaft portion 22 and a flange portion 24. The shaft portion 22 is a cylinder with a circular cross section. However, this is not limited thereto, and for example, if the cylindrical portion 14 is rectangular, the cross section of the shaft portion 22 will also be rectangular. One axial end portion 23 of the shaft portion 22 presses the layer of powder on the upper surface 13 of the base portion 12.

[0028] The diameter of the shaft portion 22 is set so as to ensure a sufficient gap between the shaft portion 22 and the inner circumferential surface 11 of the cylindrical member 10. If the gap is small, powder that gets between the shaft portion 22 and the inner circumferential surface 11 makes it difficult for the shaft portion 22 to slide against the inner circumferential surface 11. In contrast, by increasing the distance between the shaft portion 22 and the inner circumferential surface 11 as in this embodiment, the shaft portion 22 can slide appropriately against the inner circumferential surface 11 even if powder gets between the shaft portion 22 and the inner circumferential surface 11.

[0029] The flange portion 24 is connected to the other axial end of the shaft portion 22, and the diameter of the flange portion 24 is larger than the diameter of the shaft portion 22. The flange portion 24 is connected to a hydraulic cylinder (not shown) that is a drive source for moving the pressure member 20 up and down. The drive source is positioned in a standby position shown in Fig. 2 except when the pressure member 20 is applying pressure to the first layer 50 and the second layer 52, and is moved from the standby position to the pressure position shown in Fig. 1 when applying pressure to the first layer 50 and the second layer 52.

[0030] The pressing member 20 pressurizes the powder layer immediately after the powder is filled into the bottom of the cylindrical member 10. Specifically, immediately after the first layer 50 and the second layer 52 are formed inside the cylindrical member 10, the pressing member 20 pressurizes the first layer 50 and the second layer 52.

[0031] The guide portion 30 guides the pressing member 20 as it moves between the standby position and the pressing position. Specifically, the guide portion 30 prevents the pressing member 20 from becoming tilted when it moves from the standby position to the pressing position. In other words, the guide portion 30 guides the pressing member 20 so that it moves parallel to the axial direction of the tubular member 10. This makes it easier to apply pressure to desired positions of the first layer 50 and the second layer 52 of the pressing member 20.

[0032] The guide portion 30 is provided so as to protrude further toward the center of the cylindrical member 10 than the inner peripheral surface 11 of the cylindrical member 10. Therefore, the pressure applying member 20 slides on the guide portion 30, not on the cylindrical member 10. Specifically, the sliding surface 31 of the guide portion 30 is the sliding surface 31 on which the pressure applying member 20 slides.

[0033] The guide portion 30 is provided on the upper part of the tubular member 10. The guide portion 30 is positioned by fitting into the tapered portion 15 of the tubular member 10. The guide portion 30 is provided in a cylindrical shape, as shown in FIG. 3. The axial length of the guide portion 30 is shorter than the axial length of the tubular member 10. Specifically, the axial length of the guide portion 30 is shorter than half the axial length of the tubular member 10.

[0034] The effect of providing the guide portion 30 will be described below in comparison with a comparative example shown in FIG. 4 is a schematic diagram illustrating a comparative example. The molding apparatus 100 shown in the comparative example is not provided with the guide section 30 of this embodiment. Because the distance between the pressure member 120 and the inner peripheral surface 111 of the tubular member 110 is large, when the pressure member 120 moves from the standby position to the pressure position, the pressure member 120 is likely to be in an oblique position as shown in FIG. 4, rather than being parallel to the axial direction of the tubular member 110.

[0035] When the pressing member 120 presses the first layer 50 and the second layer 52 at an angle, the pressing member 120 cannot apply uniform pressure to the first layer 50 and the second layer 52. As a result, the first layer 50 and the second layer 52 have portions that are excessively pressed by the pressing member 120 and portions that are not sufficiently pressed. In the portions where the pressure is excessive, the powder is destroyed by the compressive stress. On the other hand, in the portions where the pressure is insufficient, the powder does not stick together and gaps are likely to remain, which may prevent the powder from functioning as an element (such as a positive electrode layer) of an all-solid-state battery.

[0036] In contrast, in the molding apparatus 1 of this embodiment, by providing a guide portion 30 on the upper portion of the tubular member 10, the pressing member 20 can easily move parallel to the axial direction of the tubular member 10, and therefore the pressing member 20 can uniformly pressurize the first layer 50 and the second layer 52 inside the tubular member 10. This makes it possible to prevent the first layer 50 and the second layer 52 from having portions that are excessively pressurized or insufficiently pressurized, and therefore it is possible to mold elements of an all-solid-state battery (here, the positive electrode layer and the solid electrolyte layer) that can properly perform their functions.

[0037] <Detailed configuration of guide portion 30> When powder is filled into the cylindrical member 10, some of the powder may float within the cylindrical member 10. In this embodiment, the sliding surface 31 of the guide portion 30 is not smooth so that the floating powder does not adversely affect the sliding of the pressing member 20 relative to the guide portion 30. The detailed configuration of the guide portion 30 will be described below with reference to FIG. 5.

[0038] Fig. 5 is a schematic diagram for explaining the detailed configuration of the guide part 30. As shown in Fig. 5, a groove 32, a first recess 34, and a second recess 36 are provided on the sliding surface 31 of the guide part 30. Note that Fig. 5 shows the groove 32 in a simplified manner.

[0039] The grooves 32 are provided along the circumferential direction of the guide portion 30. Specifically, the grooves 32 are formed over the entire sliding surface 31. Here, the grooves 32 are provided toward the center of the sliding surface 31. The depth of the grooves 32 is set to a predetermined size, for example, 10 μm. The surface roughness of the grooves 32 is greater than the surface roughness of the sliding surface 31. By providing such grooves 32, the powder filled and floating in the cylindrical member 10 is more likely to adhere to the grooves 32 rather than to the sliding surface 31. This makes it possible to prevent poor sliding of the pressing member 20 caused by the powder adhering to the sliding surface 31 getting caught in the pressing member 20.

[0040] The grooves 32 are formed in a lattice pattern, specifically a cross-hatch pattern. By forming the grooves 32 in a lattice pattern, the area in which the grooves 32 are formed on the sliding surface 31 can be widened. This makes it easier for powder to adhere to the grooves 32, and prevents powder from adhering to the sliding surface 31. As a result, poor sliding of the pressing member 20 can be prevented.

[0041] The first recess 34 is formed along the circumferential direction on the sliding surface 31, similar to the groove 32. The first recess 34 has the function of collecting powder floating inside the cylindrical member 10. The depth of the first recess 34 is greater than the depth of the groove 32, and is, for example, 1 mm. By providing the first recess 34 with such a depth, the first recess 34 can collect a large amount of powder, thereby further suppressing the adhesion of powder to the sliding surface 31.

[0042] The first recess 34 is provided at one end of the sliding surface in the axial direction. Specifically, the first recess 34 is provided below the groove 32 on the sliding surface 31. This makes it easier for the powder filled inside the cylindrical member 10 to adhere to the first recess 34, which is closer to the second layer 52 than the groove 32, and therefore makes it easier for the first recess 34 to collect the powder.

[0043] The second recess 36, like the first recess 34, is formed on the sliding surface 31 of the guide part 30. The second recess 36 also has the function of collecting powder. That is, the second recess 36 collects the powder that is filled and floating inside the cylindrical member 10. As a result, even if the pressing member 20 moves immediately after the powder is filled, the powder is collected in the second recess 36, which prevents the powder from adhering to the pressing member 20, thereby preventing poor sliding of the pressing member 20.

[0044] The second recess 36 is provided at the other axial end of the sliding surface 31. Specifically, the second recess 36 is provided above the groove 32 on the sliding surface 31. As a result, the first recess 34 and the second recess 36, which are located at both axial ends, surround the groove 32. Here, the shape of the second recess 36 is the same as that of the first recess 34. However, this is not limiting, and the depth of the second recess 36 may be smaller than the depth of the first recess 34.

[0045] In the above description, both the first recess 34 and the second recess 36 are formed on the sliding surface 31 of the guide part 30, but this is not limiting. For example, only one of the first recess 34 and the second recess 36 (for example, the first recess 34) may be formed on the sliding surface 31 of the guide part 30. Even in this case, the first recess 34 can capture floating powder.

[0046] In the above description, the groove 32 is formed on the axial center side of the sliding surface 31, but this is not limiting. For example, if the first recess 34 and the second recess 36 are not formed on the sliding surface 31, the groove 32 may be formed on the entire sliding surface 31.

[0047] <Effects of this embodiment> The molding apparatus 1 of the present embodiment described above has a cylindrical guide portion 30 that is provided on the upper portion of the tubular member 10 so as to protrude toward the center of the tubular member 10 beyond the inner surface 11 of the tubular member 10 and that slidably guides the pressure member 20. As a result, even if the gap between the cylindrical member 10 and the pressure applying member 20 is large, the guide portion 30 can guide the pressure applying member 20 to move along the axial direction, thereby preventing the pressure applying member 20 from applying pressure to the powder layer inside the cylindrical member 10 in an oblique position. As a result, the pressure applying member 20 can apply pressure to the powder layer uniformly.

[0048] The present invention has been described above using embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. For example, all or part of the device can be configured by functionally or physically distributing or integrating any unit. Furthermore, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effects of the new embodiments resulting from the combination also have the effects of the original embodiments. [Explanation of symbols]

[0049] 1 Molding equipment 10. Cylinder member 11 Inner surface 20 Pressure member 30 Guide section 31 Sliding surface 32 Groove 34 First recess 36 Second recess

Claims

1. a cylindrical member having a bottom filled with powder that is a battery material for the all-solid-state battery; a pressing member that moves along an inner circumferential surface of the cylindrical member toward the bottom and pressurizes the powder layer; a cylindrical guide portion provided at an upper portion of the cylindrical member so as to protrude further toward the center of the cylindrical member in the radial direction than the inner circumferential surface, and which slidably guides the pressing member; A molding device comprising:

2. The axial length of the guide portion is shorter than the axial length of the cylindrical member. The molding apparatus of claim 1 .

3. A sliding surface of the guide portion on which the pressing member slides has a lattice-shaped groove formed along the circumferential direction. The molding apparatus of claim 1 .

4. The groove is formed over the entire circumferential direction of the sliding surface. The molding apparatus according to claim 3.

5. a sliding surface of the guide portion on which the pressing member slides, the sliding surface having a recess formed along a circumferential direction thereof, the recess being capable of collecting the powder floating inside the cylindrical member; The molding apparatus of claim 1 .

6. The recessed portion is formed at both axial ends of the guide portion. The molding apparatus according to claim 5.

7. the pressing member presses the powder layer immediately after the powder is filled in the bottom portion. The molding apparatus according to any one of claims 3 to 6.

8. The cylindrical member is filled with a first powder, and then filled with a second powder different from the first powder, the pressing member presses the first powder layer and the second powder layer. The molding apparatus of claim 1 .

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