Method for manufacturing all-solid-state battery and apparatus for manufacturing all-solid-

Abstract

To provide a manufacturing method of an all-solid battery capable of charging each of a plurality of electrode laminates to a predetermined voltage in a charging step after a pressing step, and to provide a manufacturing device of the all-solid battery.SOLUTION: The method for manufacturing the all-solid-state battery 1 includes an electrode-stacked-body forming step (S1) of forming the electrode-stacked body 2, a first stacked-body forming step (S2) of forming the first stacked body 10 by disposing the first electrode-stacked-body 2A between the first positive-electrode plate 1011A and the first negative-electrode plate 1012A and disposing the second electrode-stacked-body 2B between the second positive-electrode plate 1011B and the second negative-electrode plate 1012B, a pressing step (S3) of pressing the first stacked body 10, and a charging step () of charging the first electrode-stacked-body and the second electrode-stacked-body in parallel connection while maintaining the first stacked body 10. 2A 2B S4.SELECTED DRAWING: Figure 8

Description

[Technical Field]

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

[0002] Conventionally, a method for manufacturing an all-solid-state lithium-ion secondary battery has been proposed, which includes the steps of: preparing a laminate of a positive electrode layer, an electrolyte layer, and a negative electrode layer (laminate preparation step); compressing and housing the prepared laminate in a battery case to prepare a battery (battery preparation step); and repeatedly charging and discharging the prepared battery (charge and discharge treatment step). It has also been disclosed that in the battery preparation step, a plurality of laminates are stacked so that a current collector is disposed between the positive electrode layer of one laminate and the negative electrode layer of another laminate (see Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5402090 Summary of the Invention [Problem to be solved by the invention]

[0004] In the manufacturing method described in Patent Document 1, in the charge-discharge treatment step, multiple laminates are connected in series (i.e., multiple laminates are stacked so that a current collector is disposed between the positive electrode layer of one laminate and the negative electrode layer of another laminate), and the battery is repeatedly charged and discharged.

[0005] Therefore, there is a possibility that each stacked body cannot be charged to a predetermined voltage due to the difference in capacitance between the stacked bodies.

[0006] The present invention provides a method and an apparatus for manufacturing an all-solid-state battery that can charge each of a plurality of electrode stacks to a predetermined voltage in a charging step after a pressing step. [Means for solving the problem]

[0007] The present invention [1] relates to an electrode stack forming process for dry-forming an electrode stack having a positive electrode layer made from a powder containing a positive electrode active material, a negative electrode layer made from a powder containing a negative electrode active material, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer in a first direction and made from a powder of a solid electrolyte; a first press set having a first electrode stack, a first metallic positive electrode plate in contact with the positive electrode layer of the first electrode stack, and a first metallic negative electrode plate in contact with the negative electrode layer of the first electrode stack; a second electrode stack, a second metallic positive electrode plate in contact with the positive electrode layer of the second electrode stack, and a second metallic negative electrode plate in contact with the negative electrode layer of the second electrode stack; The method for manufacturing an all-solid-state battery includes: a first stack body forming step of forming a first stack body in which a second press set and an insulator that is disposed between the first press set and the second press set and insulates the second press set from the first press set are stacked in the first direction; a pressing step of pressing the first electrode stack body and the second electrode stack body by pressing the first stack body in the first direction; and a charging step of connecting the first positive electrode plate and the second positive electrode plate in parallel and connecting the first negative electrode plate and the second negative electrode plate in parallel while maintaining the first stack body.

[0008] According to this method, a first electrode stack is placed between a first positive electrode plate and a first negative electrode plate, and a second electrode stack is placed between a second positive electrode plate and a second negative electrode plate to form a first stack body (first stack body forming step), and the first stack body is pressed (pressing step).

[0009] This makes it possible to press a plurality of electrode stacks (first electrode stacks and second electrode stacks) in one pressing step.

[0010] Furthermore, the first electrode laminate is pressed with a first positive electrode plate and a first negative electrode plate, and the second electrode laminate is pressed with a second positive electrode plate and a second negative electrode plate.

[0011] Therefore, the first electrode laminate and the second electrode laminate can be pressed separately, and damage to the first electrode laminate and the second electrode laminate can be prevented during the pressing process.

[0012] Furthermore, in the charging step, the first electrode stack and the second electrode stack are charged in a parallel connection.

[0013] Therefore, in the charging step after the pressing step, each of the plurality of electrode stacks can be charged to a predetermined voltage.

[0014] Furthermore, by charging the first electrode stack and the second electrode stack while maintaining the first stack body, the first electrode stack and the second electrode stack can be charged while maintaining the shapes of the first electrode stack and the second electrode stack.

[0015] This reduces the internal stress remaining in each electrode laminate (first electrode laminate and second electrode laminate) after the pressing process, and prevents each electrode laminate from being deformed by the remaining internal stress after the pressure applied to each electrode laminate is released.

[0016] The present invention [2] includes the method for manufacturing an all-solid-state battery according to the above [1], further including: a second stack body forming step of forming a second stack body in which the first electrode stack, the second electrode stack, and the current collector are stacked so that the current collector is disposed between the first electrode stack and the second electrode stack after the charging step; and a packing step of wrapping the second stack body with an exterior material.

[0017] The present invention [3] includes a manufacturing apparatus used in the manufacturing method of the all-solid-state battery of [1] or [2] above, the manufacturing apparatus for an all-solid-state battery including the first positive electrode plate, the first negative electrode plate, the second positive electrode plate, the second negative electrode plate, and the insulator.

[0018] According to this configuration, the above-described method for manufacturing an all-solid-state battery can be carried out.

[0019] The present invention [4] includes the all-solid-state battery manufacturing apparatus according to the above [3], further comprising a positive electrode conductive member that electrically connects the first positive electrode plate and the second positive electrode plate, and a negative electrode conductive member that electrically connects the first negative electrode plate and the second negative electrode plate.

[0020] With this configuration, the positive electrode conductive member can connect the first positive electrode plate and the second positive electrode plate in parallel, and the negative electrode conductive member can connect the first negative electrode plate and the second negative electrode plate in parallel.

[0021] As a result, with a simple configuration, it is possible to realize a parallel connection between the first positive electrode plate and the second positive electrode plate, and a parallel connection between the first negative electrode plate and the second negative electrode plate.

[0022] The present invention [5] includes the all-solid-state battery manufacturing apparatus according to the above [3] or [4], further comprising a jig for maintaining the first stack body.

[0023] According to this configuration, the first stack body can be maintained by the jig.

[0024] Therefore, in the charging step, the first electrode stack and the second electrode stack can be charged while the first stack body is maintained using a jig. [Effects of the Invention]

[0025] According to the method and apparatus for manufacturing an all-solid-state battery of the present invention, each of the plurality of electrode stacks can be charged to a predetermined voltage in the charging step after the pressing step. [Brief explanation of the drawings]

[0026] [Figure 1] Fig. 1A is a plan view of an all-solid-state battery, and Fig. 1B is a cross-sectional view taken along line AA of the all-solid-state battery shown in Fig. 1A. [Figure 2] Fig. 2A is a cross-sectional view showing the layer structure of the electrode laminate shown in Fig. 1B, and Fig. 2B is an enlarged view of the all-solid-state battery shown in Fig. 1B. [Figure 3] Fig. 3A is a plan view of the positive electrode current collector shown in Fig. 2B, and Fig. 3B is a cross-sectional view taken along line BB of the positive electrode current collector shown in Fig. 3A. [Figure 4] FIG. 4 is a cross-sectional view taken along CC of the all-solid-state battery shown in FIG. 1A. [Figure 5] FIG. 5 is a flowchart showing steps of a method for manufacturing an all-solid-state battery according to one embodiment of the present invention. [Figure 6] 6A and 6B are diagrams illustrating the electrode stack formation process shown in FIG. 5, in which FIG. 6A shows a state in which the openings in the screen are filled with a positive electrode mixture, and FIG. 6B shows a state in which the positive electrode mixture in the openings is transferred onto a first substrate, and a positive electrode layer is formed on the first substrate. [Figure 7] FIG. 7 is a diagram illustrating the first stack body forming step and the pressing step shown in FIG. [Figure 8] FIG. 8 is a diagram illustrating the charging process shown in FIG. [Figure 9] FIG. 9 is a perspective view of an apparatus for manufacturing an all-solid-state battery according to one embodiment of the present invention. [Figure 10] Fig. 10A is a plan view of the positive electrode plate shown in Fig. 9. Fig. 10B is a plan view of the negative electrode plate shown in Fig. 9. [Figure 11] FIG. 11 is a side view of the jig. DETAILED DESCRIPTION OF THE INVENTION

[0027] 1.All-solid-state battery A description will be given of one embodiment of the all-solid-state battery 1. Note that the shape of the all-solid-state battery 1 is not limited to this embodiment as long as it is an all-solid-state battery manufactured according to the present invention [1] above.

[0028] As shown in FIGS. 1A and 1B, the all-solid-state battery 1 includes a plurality of electrode laminates 2, a plurality of current collectors 3, a positive electrode lead 4, a negative electrode lead 5, and an exterior material 6.

[0029] (1) Electrode laminate In this embodiment, the electrode stack 2 has a sheet shape. The electrode stack 2 has a substantially rectangular shape when viewed from a first direction. The first direction is the thickness direction of the electrode stack 2. The shape of the electrode stack 2 is not limited. The electrode stack 2 may have a plate shape or a film shape. Furthermore, the electrode stack 2 may have a substantially circular shape when viewed from the first direction.

[0030] The electrode stack 2 has a thickness of, for example, 100 μm or more, or preferably 200 μm or more, and for example, 1000 μm or less, or preferably 800 μm or less.

[0031] 2A, the electrode stack 2 has a positive electrode layer 21, a negative electrode layer 22, and a solid electrolyte layer 23. The electrode stack 2 is composed of the positive electrode layer 21, the negative electrode layer 22, and the solid electrolyte layer 23. The electrode stack 2 has the solid electrolyte layer 23 between the positive electrode layer 21 and the negative electrode layer 22.

[0032] (1-1) Positive electrode layer The positive electrode layer 21 is disposed apart from the negative electrode layer 22 in the first direction. The positive electrode layer 21 is disposed on the opposite side of the solid electrolyte layer 23 from the negative electrode layer 22 in the first direction. The positive electrode layer 21 is in contact with the solid electrolyte layer 23 but is not in contact with the negative electrode layer 22.

[0033] The positive electrode layer 21 is made of a powder containing a positive electrode active material. The positive electrode layer 21 may contain a resin such as a binder. In this embodiment, the positive electrode layer 21 is made of a mixture (positive electrode composite) of a powder of the positive electrode active material and a powder of a solid electrolyte. The positive electrode layer 21 may contain a conductive additive. The positive electrode layer 21 does not have to contain a solid electrolyte. The positive electrode layer 21 may be made of only the positive electrode active material.

[0034] The positive electrode active material may be, for example, a lithium-containing oxide. Examples of the lithium-containing oxide include lithium-nickel composite oxide (LiNi X M 1-X O2), lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium-nickel-cobalt-aluminum composite oxide (LiNi 0.8 Co 0.15 Al 0.05 O2, NCA-based layered oxides), lithium manganese oxide (spinel-type lithium manganese oxide (LiMn2O4)), and Li-excess composite oxides (Li2MnO3-LiMO2).

[0035] The positive electrode active material is not limited to lithium-containing oxides as long as it is capable of inserting and extracting lithium ions. Examples of the positive electrode active material include olivine-based compounds (LiMPO4) and sulfur-containing compounds (Li2S).

[0036] In the above chemical formula, M represents a transition metal.

[0037] As the positive electrode active material, a lithium-containing oxide containing at least one selected from the group consisting of Co, Ni, and Mn is preferable, from the viewpoint of easily obtaining a high capacity.

[0038] In addition, the surface of the positive electrode active material may be covered with a coating material from the viewpoint of improving rate characteristics.

[0039] As a coating material, for example, Li4Ti5O 12, LiTaO3, Li4NbO3, LiAlO2, Li2ZrO3, Li2WO4, Li2TiO3, Li2B4O7, Li3PO4, Li2MoO4, LiBO2, alumina (Al2O3), and carbon (C).

[0040] The positive electrode active materials can be used alone or in combination of two or more kinds.

[0041] The solid electrolyte exhibits lithium ion conductivity. Examples of the solid electrolyte include organic solid electrolytes and inorganic solid electrolytes.

[0042] Inorganic solid electrolytes include, for example, sulfides, oxides, nitrides, and hydrides.

[0043] The sulfide may, for example, contain Li2S and another sulfide containing at least one element selected from the group consisting of Group 13 elements, Group 14 elements, and Group 15 elements of the periodic table.

[0044] Examples of Group 13 elements, Group 14 elements, and Group 15 elements of the periodic table include P, Si, Ge, As, Sb, and Al, preferably P, Si, and Ge, and more preferably P.

[0045] Specific examples of sulfides include Li2S-SiS2, Li2S-P2S5, Li2S-GeS2, Li2S-B2S3, Li2S-Ga2S3, Li2S-Al2S3, Li2S-GeS2-P2S5, Li2S-Al2S3-P2S5, Li2S-P2S3, Li2S-P2S3-P2S5, LiX-Li2S-P2S5, LiX-Li2S-SiS2, and LiX-Li2S-B2S3 (X: I, Br, or Cl).

[0046] The solid electrolyte is preferably an inorganic solid electrolyte, more preferably a sulfide. The solid electrolyte may be used alone or in combination of two or more. The ratio of the positive electrode active material to the solid electrolyte is not limited.

[0047] The positive electrode layer 21 has a thickness of, for example, 50 μm or more, or preferably 100 μm or more. The positive electrode layer 21 has a thickness of, for example, 500 μm or less, or preferably 300 μm or less.

[0048] (1-2) Negative electrode layer The negative electrode layer 22 is disposed away from the positive electrode layer 21 in the first direction. The negative electrode layer 22 is disposed on the opposite side of the positive electrode layer 21 in the first direction with respect to the solid electrolyte layer 23. The negative electrode layer 22 is in contact with the solid electrolyte layer 23 but is not in contact with the positive electrode layer 21.

[0049] The negative electrode layer 22 is made of a powder containing a negative electrode active material. The negative electrode layer 22 may contain a resin such as a binder. In this embodiment, the negative electrode layer 22 is made of a mixture (negative electrode composite) of a powder of the negative electrode active material and a powder of a solid electrolyte. The negative electrode layer 22 may contain a conductive additive. The negative electrode layer 22 does not necessarily need to contain a solid electrolyte. The negative electrode layer 22 may be made of only the negative electrode active material.

[0050] The negative electrode active material is not limited as long as it is a material capable of inserting and extracting lithium ions, and examples of the negative electrode active material include carbon materials, metals and alloys thereof, semimetals, and compounds of metals or semimetals.

[0051] Examples of carbon materials include graphite (natural graphite, artificial graphite), hard carbon, and amorphous carbon. Examples of metals and their alloys include lithium and its alloys. Examples of metalloids include silicon. Examples of metal or metalloid compounds include oxides, sulfides, nitrides, hydrates, and silicides (lithium silicides) of metals or metalloids. Examples of metal or metalloid oxides include titanium oxide and silicon oxide.

[0052] The negative electrode active material can be used alone or in combination of two or more kinds, for example, silicon oxide and a carbon material can be used in combination as the negative electrode active material.

[0053] Examples of the solid electrolyte contained in the negative electrode layer 22 include the solid electrolytes described above. Preferably, the solid electrolyte contained in the negative electrode layer 22 is the same as the solid electrolyte contained in the positive electrode layer 21. The ratio of the negative electrode active material to the solid electrolyte is not limited.

[0054] The thickness of the negative electrode layer 22 is approximately the same as the thickness of the positive electrode layer 21. The thickness of the negative electrode layer 22 is, for example, 50 μm or more, or preferably 100 μm or more. The thickness of the negative electrode layer 22 is, for example, 500 μm or less, or preferably 300 μm or less.

[0055] (1-3) Solid electrolyte layer The solid electrolyte layer 23 is disposed between the positive electrode layer 21 and the negative electrode layer 22 in the first direction. The solid electrolyte layer 23 is made of a solid electrolyte powder. The solid electrolyte layer 23 may contain a resin such as a binder.

[0056] The solid electrolyte may be, for example, any of the solid electrolytes described above. Preferably, the solid electrolyte is the same as the solid electrolyte contained in the positive electrode layer 21.

[0057] The solid electrolyte layer 23 is thinner than the positive electrode layer 21 and the negative electrode layer 22. The thickness of the solid electrolyte layer 23 is, for example, 10 μm or more, or preferably 30 μm or more. The thickness of the solid electrolyte layer 23 is, for example, 300 μm or less, or preferably 100 μm or less.

[0058] (2) Current collector 2B, in the case of parallel connection, each of the multiple current collectors 3 is stacked alternately with each of the multiple electrode stacks 2. The multiple current collectors 3 include a positive electrode current collector 3A and a negative electrode current collector 3B. The positive electrode current collector 3A contacts the positive electrode layer 21 of the electrode stack 2. The negative electrode current collector 3B contacts the negative electrode layer 22 of the electrode stack 2.

[0059] Specifically, in this embodiment, the positive electrode current collector 3A, the first electrode laminate 2A, the negative electrode current collector 3B, the second electrode laminate 2B, and the positive electrode current collector 3A are stacked in this order from one side to the other in the first direction. In the first direction, one negative electrode current collector 3B is disposed between the negative electrode layer 22 of the first electrode laminate 2A and the negative electrode layer 22 of the second electrode laminate 2B. In other words, in the first direction, one current collector 3 is disposed between two electrode laminates 2. In the case of series connection, multiple electrode laminates 2 are stacked so that the positive electrode layer 21, the solid electrolyte layer 23, and the negative electrode layer 22 are stacked in the same order, and current collectors 3 are disposed only in the uppermost and lowermost layers.

[0060] As shown in FIGS. 3A and 3B, the current collector 3 has a conductor 31, an insulating member 32, and an adhesive layer 33.

[0061] (2-1) Conductors The conductor 31 is made of, for example, a metal and has a laminated portion 311 and a tab 312.

[0062] The laminate portion 311 extends in the second direction and the third direction. The second direction is perpendicular to the first direction. The third direction is perpendicular to both the first direction and the second direction. The laminate portion 311 has a sheet shape. The laminate portion 311 has one side S1 and the other side S2 in the first direction. In other words, the conductor 31 has one side S1 and the other side S2 in the first direction. The laminate portion 311 contacts the electrode laminate 2. When the current collector 3 is a positive electrode current collector 3A, the laminate portion 311 contacts the positive electrode layer 21 of the electrode laminate 2. When the current collector 3 is a negative electrode current collector 3B, the laminate portion 311 contacts the negative electrode layer 22 of the electrode laminate 2.

[0063] The tab 312 is disposed on an edge of the laminate portion 311. In the present embodiment, the tab 312 is disposed on one edge of the laminate portion 311 in the third direction. The tab 312 protrudes from the edge of the laminate portion 311. The tab 312 may be a separate member from the laminate portion 311 and may be joined to the laminate portion 311. The tab 312 has a belt shape. The tab 312 does not contact the electrode laminate 2. When the current collector 3 is a positive electrode current collector 3A, the conductor 31 has a positive electrode tab 312A as the tab 312. When the current collector 3 is a negative electrode current collector 3B, the conductor 31 has a negative electrode tab 312B as the tab 312. When the electrode laminate 2, the positive electrode current collector 3A, and the negative electrode current collector 3B are stacked, the negative electrode tab 312B is disposed away from the positive electrode tab 312A. In a state in which the electrode laminate 2, the positive electrode current collector 3A, and the negative electrode current collector 3B are stacked, the negative electrode tab 312B does not overlap with the positive electrode tab 312A in the first direction.

[0064] The thickness of the conductor 31 is, for example, 1 μm or more, or preferably 5 μm or more, and for example, 100 μm or less, or preferably 50 μm or less.

[0065] Examples of materials for the conductor 31 include copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), indium (In), lithium (Li), tin (Sn), and alloys thereof.

[0066] (2-2) Insulating material As shown in FIG. 3B, the insulating member 32 is laminated on one surface S1 of the conductor 31. As shown in FIG. 3A, the insulating member 32 is disposed on the laminated portion 311 of the conductor 31. The insulating member 32 is laminated on the peripheral edge of the laminated portion 311 of the conductor 31. The insulating member 32 has a substantially rectangular frame shape when viewed from the first direction. The insulating member 32 is not disposed on the tab 312 of the conductor 31.

[0067] When the electrode laminate 2, the positive electrode current collector 3A, and the negative electrode current collector 3B are stacked, the insulating member 32 is disposed around the electrode laminate 2. As shown in Fig. 1B, when the electrode laminate 2, the positive electrode current collector 3A, and the negative electrode current collector 3B are stacked, the insulating member 32 is disposed between the positive electrode current collector 3A and the negative electrode current collector 3B in the first direction. When the electrode laminate 2, the positive electrode current collector 3A, and the negative electrode current collector 3B are stacked, the insulating member 32 insulates the positive electrode current collector 3A from the negative electrode current collector 3B.

[0068] In the first direction, the thickness of the insulating member 32 is thinner than the thickness of the electrode stack 2. When the current collector 3 does not have the adhesive layer 33, the thickness of the insulating member 32 may be the same as the thickness of the electrode stack 2. The thickness of the insulating member 32 is, for example, 50 μm or more, or preferably 75 μm or more, and for example, 500 μm or less, or preferably 400 μm or less.

[0069] Examples of materials for the insulating member 32 include polyethylene terephthalate and polyimide.

[0070] (2-3) Adhesive layer As shown in Fig. 3B, the adhesive layer 33 is laminated on the other surface S2 of the conductor 31 at the peripheral edge of the conductor 31. The current collector 3 does not need to have the adhesive layer 33. As shown in Fig. 1B, in a state in which one electrode stack 2 is stacked between two current collectors 3, the adhesive layer 33 of the current collector 3 arranged on the other side of the electrode stack 2 in the first direction is adhered to the insulating member 32 of the current collector 3 arranged on one side of the electrode stack 2 in the first direction.

[0071] The sum of the thickness of the adhesive layer 33 and the thickness of the insulating member 32 is equal to or less than the thickness of the electrode stack 2. The thickness of the adhesive layer 33 is, for example, 30 μm or more, or preferably 50 μm or more, and for example, 300 μm or less, or preferably 200 μm or less.

[0072] The adhesive layer 33 is preferably insulating. Examples of materials for the adhesive layer 33 include resins such as acrylic, polyimide, and silicone, and nonwoven fabrics impregnated with these resins.

[0073] (3) Positive and negative electrode leads As shown in FIG. 1A, a portion of the positive electrode lead 4 is exposed from the exterior packaging material 6. As shown in FIG. 4, the positive electrode lead 4 is joined to a positive electrode tab 312A inside the exterior packaging material 6. This electrically connects the positive electrode lead 4 to the positive electrode current collector 3A. The positive electrode lead 4 is not connected to the negative electrode current collector 3B.

[0074] As shown in FIG. 1A, a portion of the negative electrode lead 5 is exposed from the exterior packaging material 6. The negative electrode lead 5 is joined to a negative electrode tab 312B (see FIG. 3A) inside the exterior packaging material 6. This allows the negative electrode lead 5 to be electrically connected to the negative electrode current collector 3B (see FIG. 1B). The negative electrode lead 5 is not connected to the positive electrode current collector 3A.

[0075] The positive electrode lead 4 and the negative electrode lead 5 each have, for example, a substantially rectangular flat plate shape. Examples of materials for the positive electrode lead 4 and the negative electrode lead 5 include pure metals and alloys. Examples of pure metals include copper, nickel, aluminum, gold, and platinum. Examples of alloys include alloys of the above pure metals, stainless steel, and titanium. The positive electrode lead 4 and the negative electrode lead 5 may be plated. For example, the positive electrode lead 4 and the negative electrode lead 5 may be copper plates having a nickel-plated layer and a gold-plated layer.

[0076] (4) Exterior materials 1A and 1B, an exterior material 6 covers a laminate of an electrode laminate 2 and a current collector 3. An example of the exterior material 6 is a metal laminate film in which resin films are laminated on both sides of a metal foil.

[0077] 2. Manufacturing method of all-solid-state batteries Next, a method for manufacturing the above-mentioned all-solid-state battery 1 will be described.

[0078] 5, the method for manufacturing the all-solid-state battery 1 includes an electrode stack forming step (S1), a first stack body forming step (S2), a pressing step (S3), a charging step (S4), a second stack body forming step (S5), and a packing step (S6). In the method for manufacturing the all-solid-state battery 1, the electrode stack forming step (S1), the first stack body forming step (S2), the pressing step (S3), the charging step (S4), the second stack body forming step (S5), and the packing step (S6) are carried out in this order.

[0079] (1) Electrode laminate formation process In the electrode stack formation step (S1), the electrode stack 2 is formed by a dry method. Specifically, the electrode stack 2 is formed on the first substrate F1 by electrostatic screen printing.

[0080] Specifically, first, a positive electrode composite is prepared by mixing a powder of a positive electrode active material and a powder of a solid electrolyte. Then, a negative electrode composite is prepared by mixing a powder of a negative electrode active material and a powder of a solid electrolyte. The positive electrode composite and the negative electrode composite may contain a binder. The positive electrode composite is preferably composed of a powder of a positive electrode active material and a powder of a solid electrolyte. The negative electrode composite is preferably composed of a powder of a negative electrode active material and a powder of a solid electrolyte.

[0081] Next, as shown in FIG. 6A, the positive electrode composite material M1 is filled into the openings OP of a screen SC having a predetermined volume.

[0082] 6B, the positive electrode composite material M1 in the opening OP is pushed out toward the first substrate F1 and transferred onto the first substrate F1 by electrostatic force, thereby forming the positive electrode layer 21 on the first substrate F1.

[0083] Next, in the same manner as in the formation of the positive electrode layer 21, the solid electrolyte layer 23 is formed on the positive electrode layer 21, and the negative electrode layer 22 is formed on the solid electrolyte layer 23.

[0084] As a result, the electrode stack 2 (see FIG. 2A) is formed on the first base material F1.

[0085] The material of the first substrate F1 is not limited as long as it can be electrostatically screen printed. Examples of the material of the first substrate F1 include metal foil. Examples of the metal foil include aluminum foil.

[0086] The order in which the positive electrode layer 21, the negative electrode layer 22, and the solid electrolyte layer 23 are formed is not limited as long as the electrode stack 2 can be formed. The negative electrode layer 22 may be formed on the first substrate F1, the solid electrolyte layer 23 may be formed on the negative electrode layer 22, and the positive electrode layer 21 may be formed on the solid electrolyte layer 23.

[0087] (2) First stack body forming process Next, in the first stack body forming step (S2), the first stack body 10 is formed.

[0088] As shown in FIG. 7, the first stack 10 is formed by stacking a plurality of press sets 101 and insulators 102 in a first direction. That is, the first stack 10 has a plurality of press sets 101 and insulators 102. The number of press sets 101 is not limited. When the number of press sets 101 is three or more, the number of insulators 102 is multiple.

[0089] One press set 101 has one electrode stack 2 , one positive electrode plate 1011 , and one negative electrode plate 1012 .

[0090] The positive electrode plate 1011 contacts the positive electrode layer 21 of the electrode stack 2. The positive electrode plate 1011 is made of metal. Examples of materials for the positive electrode plate 1011 include stainless steel, carbon steel, and tool steel. The thickness of the positive electrode plate 1011 is not limited as long as a predetermined pressure can be applied to the electrode stack 2 in the pressing step (S3). The thickness of the positive electrode plate 1011 is, for example, 2 mm or more, preferably 3 mm or more. The thickness of the first positive electrode plate 1011A is, for example, 5 mm or less.

[0091] The negative electrode plate 1012 is in contact with the negative electrode layer 22 of the electrode stack 2. The negative electrode plate 1012 is made of metal. The negative electrode plate 1012 is preferably made of the same material as the positive electrode plate 1011. The negative electrode plate 1012 may be made of a different material than the positive electrode plate 1011. The thickness of the negative electrode plate 1012 is preferably the same as the thickness of the positive electrode plate 1011. The thickness of the negative electrode plate 1012 may be different from the thickness of the positive electrode plate 1011.

[0092] More specifically, in the embodiment shown in FIG. 7, the first stack 10 includes a first press set 101A, a second press set 101B, and an insulator 102. The first press set 101A includes a first electrode stack 2A, a first positive electrode plate 1011A, and a first negative electrode plate 1012A. The first positive electrode plate 1011A contacts the positive electrode layer 21 of the first electrode stack 2A. The first negative electrode plate 1012A contacts the negative electrode layer 22 of the first electrode stack 2A. The second press set 101B includes a second electrode stack 2B, a second positive electrode plate 1011B, and a second negative electrode plate 1012B. The second positive electrode plate 1011B contacts the positive electrode layer 21 of the second electrode stack 2B. The second negative electrode plate 1012B contacts the negative electrode layer 22 of the second electrode stack 2B.

[0093] The insulator 102 is disposed between the first press set 101A and the second press set 101B. The insulator 102 insulates the second press set 101B from the first press set 101A. In the embodiment shown in FIG. 7, the insulator 102 is disposed between the first positive electrode plate 1011A and the second negative electrode plate 1012B. The insulator 102 insulates the second negative electrode plate 1012B from the first positive electrode plate 1011A. Examples of materials for the insulator 102 include ceramics, polyethylene terephthalate, polyamide, and polyimide. The thickness of the insulator 102 is not limited as long as it can insulate the second press set 101B from the first press set 101A in the charging step (S4). The thickness of the insulator 102 is, for example, 0.05 mm or more, preferably 0.1 mm or more. The thickness of the insulator 102 is, for example, 2 mm or less.

[0094] In addition, to prevent the first positive electrode plate 1011A, the insulator 102, and the second negative electrode plate 1012B from shifting, the first positive electrode plate 1011A and the second negative electrode plate 1012B may be fixed with bolts or adhesive with the insulator 102 sandwiched between them.

[0095] To form the first stack body 10, the first negative electrode plate 1012A, the first electrode stack body 2A, the first positive electrode plate 1011A, the insulator 102, the second negative electrode plate 1012B, the second electrode stack body 2B, and the second positive electrode plate 1011B are stacked in this order in a first direction.

[0096] The electrode stack 2 may be stacked while being supported by the first substrate F1. A second substrate F2 (not shown) may be stacked on the electrode stack 2 on the opposite side of the first substrate F1. In this case, the first substrate F1 and the second substrate F2 are made of metal.

[0097] (3) Pressing process 7, in the pressing step (S3), the first stack body 10 is pressed in a first direction. As a result, a plurality of electrode stacks 2 (first electrode stack 2A and second electrode stack 2B) are pressed in one pressing step (S3).

[0098] More specifically, in the pressing step (S3), the first stack body 10 is placed between the press pin P1 and the press pin P2 and pressed in the first direction.

[0099] The pressure applied to the first stack body 10 in the pressing step (S3) is not limited as long as it is possible to collectively form a plurality of electrode stacks 2. The pressure applied to the first stack body 10 in the pressing step (S3) is, for example, 100 MPa or more, preferably 500 MPa or more, and for example, 5000 MPa or less, preferably 3000 MPa or less.

[0100] (4) Charging process Next, as shown in FIG. 8 , in the charging step (S4), while maintaining the first stack body 10, the positive electrode plates 1011 (the first positive electrode plate 1011A and the second positive electrode plate 1011B) are connected in parallel, and the negative electrode plates 1012 (the first negative electrode plate 1012A and the second negative electrode plate 1012B) are connected in parallel, and the electrode stacks 2 (the first electrode stack 2A and the second electrode stack 2B) are charged. Furthermore, while maintaining the first stack body 10, the charged electrode stacks 2 are discharged. One charge and one discharge constitute one charge-discharge cycle, and the charge-discharge cycle may be repeated multiple times while maintaining the first stack body 10.

[0101] Here, each electrode stack 2 expands as it is charged. Therefore, in order to charge each electrode stack 2 while maintaining the first stack body 10, each electrode stack 2 is charged while pressing the first stack body 10 in the first direction to an extent that resists the expansion of each electrode stack 2.

[0102] The pressure applied to the first stack body 10 in the charging step (S4) is lower than the pressure applied to the first stack body 10 in the pressing step (S3). The pressure applied to the first stack body 10 in the charging step (S4) is, for example, 0.005 MPa or more, preferably 30 MPa or more, and for example, 100 MPa or less, preferably 60 MPa or less.

[0103] Charging and discharging the multiple electrode stacks 2 in a parallel connection while maintaining the first stack body 10 can reduce the internal stress remaining in each electrode stack 2. This can prevent each electrode stack 2 from being deformed by the internal stress after the positive electrode plates 1011 and negative electrode plates 1012 are removed and the pressure applied to each electrode stack 2 is released.

[0104] After the charging step (S4), the electrode laminate 2 may be cut into a desired shape, if necessary. Furthermore, after the charging step (S4), at least one of the first substrate F1 (FIG. 6B) and the second substrate F2 (not shown) may be peeled off from the electrode laminate 2, if necessary.

[0105] (5) Second stack body forming process Next, in the second stack body forming step (S5), after the charging step (S4), the second stack body 20 (see FIG. 2B) is formed.

[0106] To form the second stack 20, as shown in Fig. 2B, a plurality of electrode stacks 2 and a plurality of current collectors 3 are alternately stacked so that one current collector 3 is disposed between two electrode stacks 2. The second stack formation step is completed by stacking the desired number of electrode stacks 2 and current collectors 3.

[0107] (6) Packing process 4, the positive electrode tab 312A is joined to the positive electrode lead 4, the negative electrode tab 312B is joined to the negative electrode lead 5, and the second stack body 20 is wrapped in an exterior packaging material 6. For example, the second stack body 20 is vacuum-packed in the exterior packaging material 6.

[0108] In this way, the production of the all-solid-state battery 1 is completed.

[0109] 3. All-solid-state battery manufacturing equipment Next, with reference to FIGS. 9 to 11, a manufacturing device used in the pressing step (S3) and the charging step (S4) of the manufacturing method for the all-solid-state battery 1 will be described.

[0110] The manufacturing apparatus for the all-solid-state battery 1 includes the above-described plurality of positive electrode plates 1011, a plurality of positive electrode conductive members 103, a plurality of negative electrode plates 1012, a plurality of negative electrode conductive members 104, and a plurality of insulators 102. The manufacturing apparatus for the all-solid-state battery 1 may include a jig 105 (see FIG. 11). In other words, the manufacturing apparatus for the all-solid-state battery 1 includes a first positive electrode plate 1011A, a second positive electrode plate 1011B, a positive electrode conductive member 103, a first negative electrode plate 1012A, a second negative electrode plate 1012B, a negative electrode conductive member 104, and the insulators 102. The manufacturing apparatus for the all-solid-state battery 1 may include the jig 105 (see FIG. 11).

[0111] As shown in FIG. 10A, the positive electrode plate 1011 has a plate body 10111 and a plurality of positioning portions 10112.

[0112] The plate body 10111 is made from the metals mentioned above.

[0113] The positioning portion 10112 is disposed near a corner of the plate body 10111. The positioning portion 10112 is, for example, a through hole. Preferably, the positioning portion 10112 is a bushing that penetrates the plate body 10111. The bushing extends in the first direction. The bushing has a cylindrical shape. The bushing is made of resin. The bushing is preferably a flanged bushing.

[0114] The positive conductor 103 is disposed on the periphery of the positive plate 1011. The positive conductor 103 is made of, for example, a metal leaf spring. As shown in FIG. 9 , when the positive plate 1011 and the negative plate 1012 are alternately stacked, the positive conductor 103 does not contact the negative plate 1012. When the positive plate 1011 and the negative plate 1012 are alternately stacked, the positive conductor 103 contacts the adjacent positive plate 1011. In other words, the positive conductor 103 of the first positive plate 1011A contacts the second positive plate 1011B. That is, the positive conductor 103 electrically connects the first positive plate 1011A and the second positive plate 1011B. As a result, the multiple positive plates 1011 are connected in parallel via their respective positive conductors 103.

[0115] As shown in FIG. 10B, the negative electrode plate 1012 has a plate body 10121 and a plurality of positioning portions 10122.

[0116] The plate body 10121 is made from the above-mentioned metal.

[0117] The positioning portion 10122 is disposed near a corner of the plate body 10121. When the positive electrode plate 1011 and the negative electrode plate 1012 are stacked, the positioning portion 10122 engages with the positioning portion 10112 of the positive electrode plate 1011. The positioning portion 10122 is, for example, a pin. When the negative electrode plate 1012 is stacked on top of the positive electrode plate 1011, the pin fits into the bushing of the positive electrode plate 1011. This positions the negative electrode plate 1012 relative to the positive electrode plate 1011 when the negative electrode plate 1012 is stacked on top of the positive electrode plate 1011.

[0118] The negative conductor 104 is disposed on the periphery of the negative plate 1012. The negative conductor 104 is made of, for example, a metal leaf spring. As shown in FIG. 9 , when the positive plate 1011 and the negative plate 1012 are alternately stacked, the negative conductor 104 does not contact the positive plate 1011. When the positive plate 1011 and the negative plate 1012 are alternately stacked, the negative conductor 104 contacts the adjacent negative plate 1012. In other words, the negative conductor 104 of the first negative plate 1012A contacts the second negative plate 1012B. That is, the negative conductor 104 electrically connects the first negative plate 1012A and the second negative plate 1012B. As a result, the multiple negative plates 1012 are connected in parallel via their respective negative conductors 104.

[0119] The insulator 102 is disposed between the plate body 10111 of the positive plate 1011 and the plate body 10121 of the negative plate 1012. The insulator 102 insulates the plate body 10121 of the negative plate 1012 from the plate body 10111 of the positive plate 1011.

[0120] The jig 105 maintains the first stack body 10. For example, as shown in FIG.

[0121] The base 1051 has, for example, a tray shape. The first stack body 10 is placed on the base 1051.

[0122] The pressing member 1052 is disposed on the opposite side of the first stack body 10 from the base 1051 in the first direction. The pressing member 1052 presses the first stack body 10 toward the base 1051 in the first direction.

[0123] The lock 1053 locks the pressing member 1052 to the base 1051. The lock 1053 is attached to the end of the pressing member 1052 so as to be able to swing. The lock 1053 has a hook shape that catches on the flange portion of the base 1051.

[0124] 4. Effects (1) According to the method for manufacturing the all-solid-state battery 1, as shown in FIG. 7 , a first electrode laminate 2A is disposed between a first positive electrode plate 1011A and a first negative electrode plate 1012A, and a second electrode laminate 2B is disposed between a second positive electrode plate 1011B and a second negative electrode plate 1012B to form a first stack body 10 (first stack body forming step), and the first stack body 10 is pressed (pressing step).

[0125] This allows a plurality of electrode stacks 2 (first electrode stacks 2A and second electrode stacks 2B) to be pressed in one pressing step.

[0126] Furthermore, the first electrode stack 2A is pressed with a first positive electrode plate 1011A and a first negative electrode plate 1012A, and the second electrode stack 2B is pressed with a second positive electrode plate 1011B and a second negative electrode plate 1012B.

[0127] Therefore, the first electrode stack 2A and the second electrode stack 2B can be pressed, respectively, and damage to the first electrode stack 2A and the second electrode stack 2B can be prevented during the pressing process.

[0128] Furthermore, as shown in FIG. 8, in the charging step, the first electrode stack 2A and the second electrode stack 2B are charged in a parallel connection.

[0129] Therefore, in the charging step after the pressing step, each of the plurality of electrode stacks 2 can be charged to a predetermined voltage.

[0130] Furthermore, by charging the first electrode stack 2A and the second electrode stack 2B while maintaining the first stack body 10, the first electrode stack 2A and the second electrode stack 2B can be charged while maintaining the shapes of the first electrode stack 2A and the second electrode stack 2B.

[0131] This reduces the internal stress remaining in each electrode laminate 2 (first electrode laminate 2A and second electrode laminate 2B) after the pressing process, and prevents each electrode laminate 2 from being deformed by the remaining internal stress after the pressure applied to each electrode laminate 2 is released.

[0132] (2) As shown in FIG. 9, the manufacturing apparatus for the all-solid-state battery 1 includes a plurality of positive electrode plates 1011 (a first positive electrode plate 1011A and a second positive electrode plate 1011B), a plurality of negative electrode plates 1012 (a first negative electrode plate 1012A and a second negative electrode plate 1012B), and an insulator 102.

[0133] Therefore, the above-described method for manufacturing the all-solid-state battery 1 can be carried out.

[0134] (3) As shown in FIG. 9 , the manufacturing apparatus for the all-solid-state battery 1 further includes a positive electrode conductor 103 connecting the two positive electrode plates 1011 (a first positive electrode plate 1011A and a second positive electrode plate 1011B) and a negative electrode conductor 104 connecting the two negative electrode plates 1012 (a first negative electrode plate 1012A and a second negative electrode plate 1012B).

[0135] Therefore, the positive electrode conductive member 103 allows two positive electrode plates 1011 (a first positive electrode plate 1011A and a second positive electrode plate 1011B) to be connected in parallel, and the negative electrode conductive member 104 allows two negative electrode plates 1012 (a first negative electrode plate 1012A and a second negative electrode plate 1012B) to be connected in parallel.

[0136] As a result, with a simple configuration, it is possible to realize parallel connection of a plurality of positive electrode plates 1011 and parallel connection of a plurality of negative electrode plates 1012.

[0137] (4) The manufacturing apparatus for the all-solid-state battery 1 further includes a jig 105 for holding the first stack body 10, as shown in FIG.

[0138] Therefore, the first stack body 10 can be maintained by the jig 105.

[0139] As a result, in the charging step, the first electrode stack 2A and the second electrode stack 2B can be charged while the jig 105 is used to maintain the first stack body 10. [Explanation of symbols]

[0140] 1 All-solid-state battery 2-electrode laminate 21 Positive electrode layer 22 negative electrode layer 23 Solid electrolyte layer 2A First electrode stack 2B Second electrode stack 3 Current collector 6. Exterior materials 10 First stack body 20 Second stack body 101A First Press Set 101B 2nd Press Set 102 Insulator 103 Positive electrode conductive member 104 Negative electrode conductive member 105 Jig 1011A First positive plate 1011B Second positive plate 1012A First Negative Plate 1012B Second negative plate S1 Electrode stack formation process S2 First stack body forming process S3 Pressing process S4 charging process S5 Second stack body forming process S6 Packing process

Claims

1. an electrode stack formation step of dry-forming an electrode stack including a positive electrode layer made from a powder containing a positive electrode active material, a negative electrode layer made from a powder containing a negative electrode active material, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer in a first direction and made from a powder of a solid electrolyte; a first stack formation step of forming a first stack in which a first press set having a first electrode stack, a first metallic positive electrode plate in contact with the positive electrode layer of the first electrode stack, and a first metallic negative electrode plate in contact with the negative electrode layer of the first electrode stack, a second press set having a second electrode stack, a second metallic positive electrode plate in contact with the positive electrode layer of the second electrode stack, and a second metallic negative electrode plate in contact with the negative electrode layer of the second electrode stack, and an insulator disposed between the first press set and the second press set to insulate the second press set from the first press set are stacked in the first direction; a pressing step of pressing the first stack body in the first direction to press the first electrode stack body and the second electrode stack body; a charging step of connecting the first positive electrode plate and the second positive electrode plate in parallel and connecting the first negative electrode plate and the second negative electrode plate in parallel while maintaining the first stack body, and charging the first electrode stack body and the second electrode stack body; A method for manufacturing an all-solid-state battery, comprising:

2. a second stack body forming step of forming a second stack body in which the first electrode stack, the second electrode stack, and the current collector are stacked such that a current collector is disposed between the first electrode stack and the second electrode stack after the charging step; a packing step of wrapping the second stack body in an exterior material; The method for producing an all-solid-state battery according to claim 1 , further comprising:

3. A manufacturing apparatus used in the method for manufacturing the all-solid-state battery according to claim 1, the first positive plate; the first negative electrode plate; the second positive plate; the second negative electrode plate; The insulator An all-solid-state battery manufacturing apparatus comprising:

4. a positive electrode conductive member electrically connecting the first positive electrode plate and the second positive electrode plate; a negative electrode conductive member that electrically connects the first negative electrode plate and the second negative electrode plate; The all-solid-state battery manufacturing apparatus according to claim 3 , further comprising:

5. The all-solid-state battery manufacturing apparatus according to claim 3 , further comprising a jig for maintaining the first stack body.

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