JP4925878B2 - Manufacturing method of ceramic structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for easily manufacturing a ceramic structure which has a porous layer composed of a dense body of plate form ceramics and ceramics calcined and integrated on a surface of the dense body, and which has the porous layer filled with particulates. <P>SOLUTION: A particulate dispersion liquid SOL1 into which the particulates are dispersed and a laminate (structure before fillng) 20B of the porous layer 22 and the dense body 21 are prepared in this manufacturing method. Next, the structure before fillng is arranged at a prescribed position in a first container 41, an exposed face (upper face) of the porous layer 22 of the structure before fillng is exposed in the particulate dispersion liquid SOL1, at least one part of the exposed face (lower face of porous layer 23) of the structure 20B before fillng is exposed in a space via a through hole 41b, and a pressure difference is made to be formed between the upper face side of the porous layer and the lower face side of the structure before fillng. The particulate dispersion liquid passes from the upper face of the porous layer 22 through the lower face of the porous layer 23, and the porous layer 22 is filled with the particulates. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention is a ceramic having a plate-like dense body made of ceramics and a porous layer made of ceramics formed by firing and integration on at least one surface of the dense body, and the porous layer is filled with fine particles. The present invention relates to a method for manufacturing a structure.

  In recent years, the demand for secondary batteries (rechargeable batteries) as power sources for mobile devices such as personal computers and mobile phones has greatly increased. One of the secondary batteries moves ions such as Li ions through an electrolyte between electrodes. Conventionally used as this electrolyte is a liquid electrolyte (electrolytic solution) such as an organic solvent. In a secondary battery using an electrolytic solution, the electrolytic solution may leak.

The all solid state battery uses a solid electrolyte instead of the electrolytic solution. Therefore, various problems associated with leakage of the electrolytic solution do not occur. Furthermore, since the electrolyte is solid in the all-solid-state battery, the battery performance is hardly deteriorated due to corrosion of the members constituting the battery. In particular, all-solid-state lithium secondary batteries (also referred to as “all-solid-state lithium ion secondary batteries”) are actively studied in various directions as secondary batteries with high energy density (for example, Patent Document 1).
JP-A-5-205741

  By the way, the present applicant has a plate-like dense body made of ceramics containing a solid electrolyte and a porous layer formed on at least one surface of the dense body. We are developing an all-solid-state battery that uses an electrolyte structure (ceramic structure). In this all-solid-state battery, a solid electrolyte porous layer is formed on a solid electrolyte dense body, and an active material (electrode active material) is filled inside the porous layer (in the pores of the porous layer). Yes. Therefore, since this all solid-state battery can increase the area of the interface between the solid electrolyte and the active material, the connection resistance between the solid electrolyte and the active material can be reduced.

  As described above, in order to manufacture this all-solid-state battery, it is necessary to fill fine pores of the porous layer with the fine particle active material necessary for the electrode. In order to improve the battery performance, it is required that the active material is sufficiently filled in the pores without being biased. Hereinafter, the sintered body of the dense body / porous layer in a state before being filled with the fine particle active material is referred to as “pre-filling structure”.

  One method for filling fine pores of the active material into the pores of the porous layer of the structure before filling is a vacuum impregnation method. More specifically, first, the structure before filling is prepared by a process such as firing, and a solution in which the active material precursor is dispersed (active material precursor solution) is prepared. An active material precursor means what changes into an electrode active material by the heat processing etc. which are performed later. Next, the active material precursor solution is dropped onto the surface of the porous layer of the structure before filling in an Ar atmosphere. After that, the active material precursor is filled into the pores of the porous layer by evacuating (depressurizing) the inside of the container containing the pre-filling structure into which the active material precursor solution is dropped. Then, the active material precursor filled in the pores is heated together with the solid electrolyte structure to volatilize a liquid such as an organic solvent contained in the active material precursor and to burn off the organic component. An active material is generated by reacting and crystallizing the material precursor itself.

However, it has been found that according to the above filling method, the fine particles of the active material cannot be efficiently filled into the pores of the porous layer. The reason is considered as described below.
(R1) When the active material precursor solution is dropped on the surface of the porous layer, air exists in the pores. Therefore, the active material precursor solution cannot reach the deep part of the porous layer. In addition, the deep part of a porous layer is an interface vicinity part of a porous layer and a dense body.
(R2) During the vacuum impregnation, the influence of air in the pores can be removed. However, part of the active material precursor solution is dried and solidified in the vicinity of the upper surface of the porous layer while the pressure inside the container is being reduced. As a result, the active material precursor solution cannot reach the deep part of the porous layer.
(R3) The concentration of the precursor in the active material precursor solution is substantially several percent, and the concentration cannot be increased. Therefore, even if the active material precursor solution is filled in the entire porous layer in one filling step, the volume of the active material after vacuum impregnation, drying and heat treatment is several percent of the pore volume of the entire porous layer. It must be.

  Therefore, it is difficult to sufficiently spread the active material precursor throughout the pores of the porous layer by a single vacuum impregnation operation. For this reason, the process of heating the dense body / porous layer fired body (solid electrolyte structure) after one vacuum impregnation operation to remove impurities remaining in the pores, and further performing the next vacuum impregnation operation Must be repeated several times. As a result, the problem that manufacturing time and manufacturing cost increase arises.

  The problems described above are not limited to all-solid-state batteries, but are common to, for example, ceramic structures that are fired bodies of dense bodies and porous layers, in which fine particles are filled in the pores of the porous layer. It is a problem to do. An example of such an apparatus is a ceramic filter or a gas sensor that supports a catalyst substance (such as a noble metal) in the pores of a porous layer.

  Accordingly, one of the objects of the present invention is to have a plate-like dense body made of ceramics and a porous layer made of ceramics which is fired and integrated on at least one surface of the dense body, and fine particles in the porous layer It is an object of the present invention to provide a method capable of easily manufacturing a ceramic structure filled with. In the present invention, the dense body is made of ceramics. Therefore, the dense body is dense, but has a porosity smaller than the porosity of the porous layer, and therefore has a fine path that substantially communicates the upper surface and the lower surface.

  This method for manufacturing a ceramic structure includes the following (1) preparation step, (2) placement step, and (3) filling execution step.

(1) The preparation step includes a fine particle dispersion liquid preparation step of preparing a fine particle dispersion liquid that is a liquid in which the fine particles are dispersed, and a pre-filling structure that is the ceramic structure before the fine particles are filled into the porous layer. A pre-filling structure preparation step for preparing a body. The execution order of the fine particle dispersion liquid preparation step and the pre-filling structure preparation step is not limited.
(2) The arranging step is a step of arranging the pre-filling structure at a predetermined position.

(3) In the filling step, the exposed surface of the porous layer that is the surface of the porous layer of the structure before filling and is not in contact with the dense body is exposed in the fine particle dispersion liquid. Expose at least part of the exposed surface of the structure before filling, which is the surface opposite to the exposed surface of the porous layer of the structure before filling, to the space, and expose the exposed surface side of the porous layer and the structure before filling of the porous layer. By causing a predetermined pressure difference between the exposed surface and the exposed surface, the fine particle dispersion liquid is passed from the exposed surface of the porous layer to the exposed surface of the structure before filling through the porous layer and the dense body. The step of filling the porous layer with the fine particles in the fine particle dispersion liquid. In this filling step, the exposed surface of the porous layer may be arranged in any direction with respect to the dense body. That is, the exposed surface of the porous layer may be arranged, for example, in an upper direction, a lower direction, and a horizontal direction with respect to the dense body.

  According to this, the fine particle dispersion liquid is changed from the exposed surface of the porous layer to the exposed surface of the structure before filling due to a pressure difference between the exposed surface side of the porous layer and the exposed surface side of the structure before filling. And move at a relatively high speed via the porous layer and the dense body. At this time, the fine particle dispersion liquid always exists on the exposed surface side of the porous layer. Therefore, the fine particle dispersion liquid passes from the exposed surface of the porous layer to the exposed surface of the structure before filling without being dried and solidified in the course of passing through the porous layer and the structure before filling. Moreover, the fine particles cannot pass through the dense body. That is, the dense body functions like a filter. Thereby, the fine particles can be continuously filled in the pores of the porous layer until the fine particles are filled in a desired amount in the pores of the porous layer. Therefore, the fine particle dispersion liquid reaches the deep part of the porous layer by a single filling process. As a result, it is possible to spread an appropriate amount of fine particles in the porous layer by a single filling step, so that the manufacturing time can be shortened and the manufacturing cost can be reduced.

In this manufacturing method,
The arranging step prepares a first container having a through hole in a part of the bottom and a second container airtightly connected to the first container through the through hole, and the porous layer is the dense body. A step of disposing the structure before filling in the first container so that the exposed surface of the structure before filling covers the through hole,
In the filling step, the fine particle dispersion liquid is stored in the first container, and the air pressure in the second container is decreased and / or the second container is added to the fine particle dispersion liquid in the first container. It is a step of applying a pressure larger than the atmospheric pressure inside,
It is preferable.

  According to this, it becomes possible to implement the manufacturing method by this invention using a simple jig | tool called a 1st container and a 2nd container. Further, in the filling step, the pressure difference may be brought about by lowering the atmospheric pressure in the second container, and the fine particle dispersion liquid in the first container is more than the atmospheric pressure in the second container. It may be brought about by applying a large pressure (eg increasing the pressure in the first container). Furthermore, the air pressure in the second container may be reduced, and a pressure larger than the air pressure in the second container may be applied to the fine particle dispersion liquid in the first container. Thereby, the suitable apparatus of a decompression device and a pressurization apparatus can be used according to the request | requirements, such as a 1st container, a 2nd container, and a structure before filling. The first container and the second container may be separate containers that can be separated from each other, or may be an integrated container.

  Further, in the above manufacturing method, after the completion of the filling step, the ceramic structure is heated, so that the porous layer is filled in the fine particle dispersion liquid other than the fine particles contained in the fine particle dispersion liquid in an undried state. An impurity removing step for removing impurities may be added.

  By additionally performing this impurity removal step, even when the fine particle dispersion liquid contains a large amount of impurities other than the fine particles (for example, organic substances such as a dispersant), these impurities can be easily removed. be able to.

In addition, in the above manufacturing method,
If the ceramic forming the dense body and the porous layer is made of a solid electrolyte and the fine particles are electrode active materials used for battery electrodes, an all solid state battery having the ceramic structure can be easily manufactured. . As a result, the manufacturing cost of the all solid state battery can be reduced.

Furthermore, when producing an all solid state battery by the above production method,
The pre-filling structure preparation step includes
A ratio of 50% by volume or more of the pore forming agent in the first green sheet containing the specific solid electrolyte and not containing the pore forming agent, and the green sheet containing the specific solid electrolyte contained in the first green sheet. A second green sheet contained in the first green sheet, and pressurizing the first green sheet and the second green sheet through an adhesive layer made of the same specific solid electrolyte contained in the first green sheet. Bonding and firing the first green sheet and the second green sheet that have been pressure-bonded together,
Is preferred.

  In the all solid state battery described above, both the electrode and the electrolyte are solid. Therefore, the contact area between the electrode and the electrolyte depends on the contact area between both particles. In the state where the firing temperature between the electrode and the electrolyte is low and sintering is not progressing, the connection between these particles is almost point contact. On the other hand, when the fusion between the particles proceeds as the sintering proceeds, the area where the electrode and the electrolyte come into contact increases. As a result, since the connection part (necking part) between the particle | grains which comprise the electrode and the particle | grains which comprise an electrolyte becomes thick, the connection resistance (impedance) in the connection interface of an electrode and an electrolyte can be reduced. Therefore, it is desirable that the firing temperature is a temperature at which the electrode and the electrolyte can be sufficiently sintered. However, in such firing, it is necessary to take into account the reaction between the electrode and the electrolyte.

  From this point of view, as described above, the first green sheet and the second green sheet contain the same solid electrolyte, and the adhesive layer that pressurizes them is an adhesive layer made of the same solid electrolyte. Thus, the problem of reactivity between them can be reduced. Therefore, they can be fired at an appropriate firing temperature at which sintering can proceed. As a result, since the connection resistance at the connection interface between the electrode and the solid electrolyte can be reduced, a high-performance all solid state battery can be manufactured.

  Another method for manufacturing a ceramic structure according to the present invention includes a plate-like dense body made of ceramics, a first porous layer made of ceramics and ceramics integrally fired on the upper and lower surfaces of the dense bodies and ceramics, respectively. A method for producing a ceramic structure having the first porous layer filled with the first fine particles and the second porous layer filled with the second fine particles, the following steps: Is included.

A. By forming the first porous layer and the second porous layer on the upper and lower surfaces of the dense body by firing, respectively, before the first fine particles are filled in the first porous layer, and the second fine particles A pre-filling structure preparation step of preparing a pre-filling structure that is the ceramic structure before filling the second porous layer.
B. Preparing a first fine particle dispersion liquid, which is a liquid in which the first fine particles are dispersed so that the first fine particles can pass through the first porous layer and cannot pass through the dense body. Liquid preparation process.
C. Preparing a second fine particle dispersion liquid, which is a liquid in which the second fine particles are dispersed so that the second fine particles can pass through the second porous layer and cannot pass through the dense body. Liquid preparation process.
The order of these preparation steps does not matter.

D. A first arrangement step of arranging the pre-filling structure in a first arrangement state;
E. Exposing the exposed surface of the first porous layer, which is the surface of the first porous layer and is not in contact with the dense body, into the first fine particle dispersion liquid, and the surface of the second porous layer, At least a part of the exposed surface of the second porous layer, which is a surface not in contact with the dense body, is exposed to the space, and between the exposed surface side of the first porous layer and the exposed surface side of the second porous layer By causing a pressure difference in the first porous layer, the first porous layer, the dense body, and the second porous layer are routed from the exposed surface of the first porous layer to the exposed surface of the second porous layer. A first filling step of filling the first porous layer with the first fine particles by passing the fine particle dispersion liquid;

  The first fine particles are filled into the first porous layer by a single first filling execution step included in the above steps. In the first filling step, the first fine particle dispersion liquid is allowed to pass from the exposed surface of the first porous layer to the exposed surface of the second porous layer due to the pressure difference. At this time, the first fine particles contained in the first fine particle dispersion liquid can pass through the first porous layer, but cannot pass through the dense body. In other words, things (for example, a solvent) other than the first fine particles contained in the first fine particle dispersion liquid pass through the first porous layer, the dense body, and the second porous layer. Therefore, the first fine particles are not filled in the second porous layer.

Furthermore, the manufacturing method of the other ceramic structure includes the following steps.
F. A second arrangement step of arranging the pre-filling structure in which the first fine particles are filled in the first porous layer in the second arrangement state;
G. The exposed surface of the second porous layer is exposed in the second fine particle dispersion liquid, and at least a part of the exposed surface of the first porous layer is exposed to the space, and the same as the exposed surface side of the second porous layer. By creating a pressure difference with the exposed surface side of the first porous layer, the second porous layer, the dense body, and the first porous layer are exposed from the exposed surface of the second porous layer to the exposed surface of the first porous layer. A second filling step of filling the second porous layer with the second fine particles by allowing the second fine particle dispersion liquid to pass through the first porous layer;

  Through the above steps, the second fine particles are filled in the second porous layer of the ceramic structure in which the first fine particles are already filled in the first porous layer. Also in the second filling step, the second fine particle dispersion liquid is allowed to pass from the exposed surface of the second porous layer to the exposed surface of the first porous layer due to the pressure difference. At this time, the second fine particles contained in the second fine particle dispersion liquid can pass through the second porous layer but cannot pass through the dense body. In other words, things (for example, a solvent) other than the second fine particles contained in the second fine particle dispersion liquid pass through the second porous layer, the dense body, and the first porous layer. Therefore, the second fine particles are not filled in the first porous layer.

  As a result, by carrying out one first filling execution step and one second filling execution step, the first fine particles are uniformly and sufficiently filled in the pores of the first porous layer, and the second porous The second fine particles are evenly and sufficiently filled in the pores of the layer. Therefore, the manufacturing time of the ceramic structure can be shortened and the manufacturing cost can be reduced.

In this manufacturing method,
The first arranging step prepares a first container having a through hole in a part of the bottom and a second container airtightly connected to the first container through the through hole, and the first porous layer. Is disposed above the dense body and the pre-filling structure is disposed in the first container so that the exposed surface of the second porous layer covers the through-hole,
In the first filling step, the first fine particle dispersion liquid is stored in the first container, and the air pressure in the second container is decreased and / or the first fine particle dispersion in the first container is reduced. A step of applying a pressure larger than the atmospheric pressure in the second container to the liquid is desirable.

Furthermore,
The second arranging step prepares a third container having a through hole in a part of the bottom and a fourth container airtightly connected to the third container through the through hole, and the second porous layer. Is disposed above the dense body and the pre-filling structure is disposed in the third container so that the exposed surface of the first porous layer covers the through-hole,
In the second filling step, the second fine particle dispersion liquid is stored in the third container, and the atmospheric pressure in the fourth container is decreased and / or the second fine particle dispersion in the third container is reduced. It is desirable to be a step of applying a pressure larger than the pressure in the fourth container to the liquid.

  The third container may be the same container as the first container, and the fourth container may be the same container as the second container. Furthermore, the first container and the second container may be separate containers that are separable from each other, or may be integrated containers. Similarly, the third container and the fourth container may be separate containers that can be separated from each other, or may be integrated containers.

  According to this, it becomes possible to implement the other manufacturing method by this invention using the simple jig | tool called a 1st-4th container. Further, in the first filling execution step, the pressure difference may be brought about by reducing the atmospheric pressure in the second container, and the atmospheric pressure in the second container is changed to the first fine particle dispersion liquid in the first container. Greater pressure (eg, increasing the air pressure in the first container). Furthermore, the air pressure in the second container may be reduced and a pressure larger than the air pressure in the second container may be applied to the first fine particle dispersion liquid in the first container. Similarly, in the second filling execution step, the pressure difference may be caused by lowering the atmospheric pressure in the fourth container, and the second fine particle dispersion liquid in the third container may be brought into the fourth container. It may be provided by applying a pressure greater than atmospheric pressure (eg, increasing the atmospheric pressure in the third container). Furthermore, the air pressure in the fourth container may be decreased and a pressure larger than the air pressure in the fourth container may be applied to the second fine particle dispersion liquid in the third container. Thereby, the suitable apparatus of a decompression device and a pressurization apparatus can be used.

  Further, the other manufacturing method may include heating the structure before filling in which the first fine particles are filled in the first porous layer after the first filling step and before the second arranging step. Preferably, the method includes a first impurity removal step of removing impurities other than the first fine particles contained in the first fine particle dispersion liquid filled in the first porous layer and in an undried state.

  Similarly, in the other manufacturing method, after the second filling step, the ceramic structure in which the first fine particles and the second fine particles are filled in the first porous layer and the second porous layer, respectively, is heated. Accordingly, it is preferable to include a second impurity removal step of removing impurities other than the second fine particles contained in the second fine particle dispersion liquid filled in the second porous layer and in an undried state.

  By additionally performing the first impurity removal step and / or the second impurity removal step, each fine particle dispersion liquid has impurities other than the corresponding first fine particles and second fine particles (for example, organic substances such as a dispersant). Even when a large amount is contained, these impurities can be easily removed.

In addition, in the other manufacturing method,
The ceramic forming the dense body, the first porous layer and the second porous layer is made of a solid electrolyte,
The first fine particles are any one of a positive electrode active material for forming a positive electrode of a battery and a negative electrode active material for forming a negative electrode of the battery,
The second fine particles are either the positive electrode active material or the negative electrode active material,
Is preferred.

  According to this, an all solid state battery including a positive electrode composed of a porous layer and a negative electrode composed of a porous layer can be manufactured very easily. As a result, the manufacturing time of the all solid state battery can be shortened and the manufacturing cost can be reduced.

Furthermore, in the other manufacturing method,
The pre-filling structure preparation step includes
A ratio of 50% by volume or more of the pore forming agent in the first green sheet containing the specific solid electrolyte and not containing the pore forming agent, and the green sheet containing the specific solid electrolyte contained in the first green sheet. The second green sheet contained in the first green sheet, the third green sheet containing the pore forming agent in a proportion of 50% by volume or more in the green sheet containing the specific solid electrolyte contained in the first green sheet, The second green sheet is pressure-bonded to the upper surface of the first green sheet through the adhesive layer made of the specific solid electrolyte contained in the first green sheet, and the adhesive layer is The third green sheet is pressure bonded to the lower surface of the first green sheet, and the first green sheet, the second green sheet, and the third green sheet that have been pressure bonded are integrally fired. Comprising the step of, it is preferable.

  According to this, as described above, the first green sheet to the third green sheet contain the same solid electrolyte, and the adhesive layer for pressure bonding them is an adhesive layer made of the same solid electrolyte. The problem of reactivity between them can be reduced. Therefore, they can be fired at an appropriate firing temperature at which sintering can proceed. As a result, since the connection resistance at the connection interface between each electrode and the solid electrolyte can be reduced, a high performance all solid state battery can be manufactured.

Embodiments of a method for manufacturing a ceramic structure according to the present invention will be described below with reference to the drawings.
<First Embodiment>
First, the manufacturing method of the ceramic structure which concerns on 1st Embodiment of this invention, and the ceramic structure manufactured by the manufacturing method are demonstrated. This ceramic structure constitutes an all-solid-type lithium secondary battery. However, the method for manufacturing a ceramic structure according to the present invention is naturally applicable not only to manufacturing all solid state batteries other than all solid state lithium secondary batteries, but also to devices other than batteries using the same ceramic structure. can do.

(Constitution)
FIG. 1 is a cross-sectional view of an all solid-state lithium secondary battery 10 manufactured by the method for manufacturing a ceramic structure according to the first embodiment of the present invention. The all solid-state lithium secondary battery 10 includes a solid electrolyte structure (ceramic structure) 20, a positive electrode collector 31, and a negative electrode collector 32.

  The solid electrolyte structure 20 includes a dense body 21, a positive electrode side porous layer 22, and a negative electrode side porous layer 23. In this example, the dense body 21, the positive electrode side porous layer 22, and the negative electrode side porous layer 23 are integrated by firing.

  The dense body 21 is made of a ceramic containing a solid electrolyte (a solid electrolyte capable of moving lithium ions). The dense body is a thin plate body. The shape of the dense body 21 in a plan view is circular as shown in FIG. 2, which is a perspective view of the solid electrolyte structure 20. That is, the dense body 21 has a disk shape. 1 corresponds to a cross section (excluding the positive electrode collector 31 and the negative electrode collector 32) obtained by cutting the solid electrolyte structure 20 along a plane along line 1-1 in FIG.

  The thickness of the dense body 21 is preferably 5 to 100 μm, more preferably 5 to 50 μm. The dense body 21 has a predetermined small porosity. The porosity of the dense body 21 is 5 to 20% when measured by a mercury intrusion method. It is. Accordingly, the dense body 21 is provided with a fine path (path through which liquid can pass) that substantially communicates the upper surface and the lower surface, although it is dense. The material and manufacturing method of the dense body 21 will be described in detail later.

  The positive electrode side porous layer 22 is made of a ceramic containing the same solid electrolyte as the solid electrolyte contained in the dense body 21. The positive electrode side porous layer 22 is a thin plate. The shape of the positive electrode side porous layer 22 in plan view is the same circle as the shape of the dense body 21 in plan view as shown in FIGS. 1 and 2. That is, the positive electrode side porous layer 22 has the same disk shape as the dense body 21. The thickness of the positive electrode side porous layer 22 is preferably 10 μm to 1 mm, more preferably 50 to 500 μm. The positive electrode side porous layer 22 is integrally formed on the upper surface of the dense body 21 (one surface of the dense body 21) by firing. The surface of the positive electrode side porous layer 22 on the side not in contact with the dense body 21 is also referred to as “exposed surface of the positive electrode side porous layer 22”.

  The positive electrode-side porous layer 22 has a porosity that is considerably larger than that of the dense body 21. The porosity of the positive electrode-side porous layer 22 is preferably 10 to 70% by volume, and more preferably 30 to 60% by volume, for example, when measured by a mercury intrusion method. Therefore, the positive electrode-side porous layer 22 has a large number of fine pores (pores, holes) 22a therein. As a result, the positive electrode-side porous layer 22 has a path that substantially communicates the upper surface and the lower surface in a state where nothing is filled in the pores 22a. The positive electrode-side porous layer 22 includes a first active material 22 b that constitutes the positive electrode of the all solid-state lithium secondary battery 10. The first active material 22b is fine particles, and is filled (supported) in the pores 22a. Thus, the positive electrode-side porous layer 22 constitutes the positive electrode of the all solid-state lithium secondary battery 10. The materials and manufacturing methods of the positive electrode side porous layer 22 and the first active material 22b will be described in detail later.

  The negative electrode side porous layer 23 is made of ceramics containing the same solid electrolyte as the solid electrolyte contained in the dense body 21. The negative electrode side porous layer 23 is a thin plate. The shape of the negative electrode side porous layer 23 in plan view is the same circle as the shape of the dense body 21 in plan view as shown in FIGS. 1 and 2. That is, the negative electrode side porous layer 23 has the same disk shape as the dense body 21 and the positive electrode side porous layer 22. The thickness of the negative electrode side porous layer 23 is preferably 10 μm to 1 mm, more preferably 50 to 500 μm. The negative electrode side porous layer 23 is integrally formed by firing on the lower surface of the dense body 21 (the other surface of the dense body 21, that is, the surface opposite to the surface on which the positive electrode side porous layer 22 is formed). . Therefore, the dense body 21 is sandwiched between the negative electrode side porous layer 23 and the positive electrode side porous layer 22 facing each other. In other words, the solid electrolyte structure 20 is a laminate in which the negative electrode side porous layer 23, the dense body 21, and the positive electrode side porous layer 22 are laminated in this order. The surface of the negative electrode side porous layer 23 that is not in contact with the dense body 21 is also referred to as “exposed surface of the negative electrode side porous layer 23”.

  The negative electrode side porous layer 23 has substantially the same porosity as the positive electrode side porous layer 22. Therefore, the negative electrode side porous layer 23 includes a large number of fine pores (holes) 23a therein. As a result, the negative electrode-side porous layer 23 has a path that substantially communicates the upper surface and the lower surface in a state where nothing is filled in the pores 23a. The negative electrode-side porous layer 23 includes a second active material 23 b that constitutes the negative electrode of the all solid-state lithium secondary battery 10. The second active material 23b is fine particles, and is filled (supported) in the pores 23a. As a result, the negative electrode-side porous layer 23 constitutes the negative electrode of the all solid-state lithium secondary battery 10. The material and manufacturing method of the negative electrode side porous layer 23 and the second active material 23b will be described in detail later.

As shown in FIG. 1, a positive electrode collecting electrode 31 is formed on the upper surface (exposed surface) of the positive electrode side porous layer 22. The positive electrode collecting electrode 31 is a metal film.
As shown in FIG. 1, a negative electrode collecting electrode 32 is formed on the lower surface (exposed surface) of the negative electrode side porous layer 23. The negative electrode collecting electrode 32 is a metal film.
The materials and manufacturing methods of the positive electrode collector 31 and the negative electrode collector 32 will be described in detail later.

(Discharging action, charging action)
In the all solid-state lithium secondary battery 10, when an electric load (not shown) is connected between the positive electrode collector 31 and the negative electrode collector 32, lithium ions are removed from the second active material 23 b of the negative electrode side porous layer 23. At the same time, electrons are supplied to the electric load via the negative electrode collecting electrode 32. The released lithium ions move in the dense body 21 and reach the positive electrode-side porous layer 22. At this time, the electrons supplied through the electrical load and the positive electrode collector 31 and the lithium ions moving in the dense body 21 are combined to form lithium, which is inserted into the first active material 22 b of the positive electrode side porous layer 22. Is done. The above is the operation of the all solid-state lithium secondary battery 10 during discharge. In addition, at the time of charge, each said substance performs the reverse movement to the above-mentioned movement. As a result, lithium in the positive electrode side porous layer 22 becomes lithium ions and moves to the negative electrode side porous layer 23 through the dense body 21.

(Method for producing solid electrolyte structure 20)
Next, a method for manufacturing the solid electrolyte structure (ceramic structure) 20 configured as described above will be described.
<1. Preparation process>
<1-1. Preparation process of active material dispersion liquid (fine particle dispersion liquid)>
<1-1-1. First Fine Particle Dispersion Liquid Preparation Step (First Active Material Dispersion Liquid Preparation Step)>
First, a first active material (first fine particle) solution (first active material dispersion liquid, first fine particle dispersion liquid) filled in the positive electrode side porous layer 22 (the pores 22a of the positive electrode side porous layer 22) is prepared. . Specifically, the first active material produced by the solid phase synthesis method or the liquid phase synthesis method is pulverized to obtain a fine powder, and the fine powder is used as an organic solvent (for example, alcohol), an aqueous solvent, and pure water. Etc. to produce a first active material dispersion liquid in which fine particles of the first active material are dispersed. Instead, the first active material is synthesized by utilizing a part of the technique used in the sol-gel method and grown to a particle size larger than the pores of the dense body 21, and then the reaction solution is used as it is for the first active material. It may be used as a substance dispersion liquid. In some cases, in order to improve the dispersibility of the first active material, the pH of the solution may be adjusted and / or a surfactant may be mixed into the first active material dispersion liquid.

  When the first active material dispersion liquid is passed from the exposed surface of the positive electrode side porous layer 22 to the exposed surface of the negative electrode side porous layer 23 in the first filling step described later, the first active material is transferred to the positive electrode side porous layer. The liquid such as the solvent excluding the first active material passes through all of the positive electrode-side porous layer 22, the dense body 21, and the negative electrode-side porous layer 23 so that it passes through the dense body 21 but cannot pass through the dense body 21. Adjusted to be able to. Specifically, the first active material dispersion solution includes a first active material dispersion solution in which the first active material is smaller in size than the positive electrode-side porous layer 22 and larger than the dense body 21. An active material dispersion solution is prepared.

<1-1-2. Second fine particle dispersion liquid preparation step>
Further, a solution (second active material dispersion liquid, second particle dispersion liquid) of the second active material (second fine particles) filled in the negative electrode side porous layer 23 (the pores 23a of the negative electrode side porous layer 23) is prepared. . The method for producing the second active material dispersion liquid is the same as the method for producing the first active material.

  When the second active material dispersion liquid is passed from the exposed surface of the negative electrode side porous layer 23 to the exposed surface of the positive electrode side porous layer 22 in a second filling step described later, the second active material is negative electrode side porous layer. The liquid such as the solvent excluding the second active material passes through all of the negative electrode side porous layer 23, the dense body 21, and the positive electrode side porous layer 22 so as to pass through the dense body 21 but not through the dense body 21. Adjusted to be able to. Specifically, in the second active material dispersion solution, the size of the particles containing the second active material is smaller than the pores of the negative electrode-side porous layer 23 and larger than the pores of the dense body 21. A substance dispersion solution is prepared.

<1-2. Pre-filling solid electrolyte structure preparation process>
<1-2-1. Green sheet production process>
Next, a solid electrolyte structure (ceramic structure) before the first active material and the second active material are filled in each of the positive electrode side porous layer 22 and the negative electrode side porous layer 23 is prepared. In this specification, the solid electrolyte structure 20 in this state is also simply referred to as “pre-fill structure”.

  More specifically, a first green sheet (ceramic green sheet) 21A containing only a specific solid electrolyte material contained in the dense body 21 and not containing a pore forming agent is prepared (see FIG. 3). ). The first green sheet 21A will become the dense body 21 later.

  Next, a pore forming agent is added to the green sheet containing the specific solid electrolyte material contained in the first green sheet 21A by 50% by volume or more, more preferably 100% by volume or more (of the pore forming agent relative to the volume of the solid electrolyte). A second green sheet (ceramic green sheet) 22A containing a volume ratio of 1 or more, more preferably 2 or more is prepared (see FIG. 3). The second green sheet 22A later becomes the positive electrode-side porous layer 22.

  Similarly, a third green in which a pore forming agent is contained in a proportion of 50% by volume or more (more preferably 100% by volume or more) in a green sheet containing a specific solid electrolyte material contained in the first green sheet 21A. A sheet (ceramic green sheet) 23A is prepared (see FIG. 3). The third green sheet 23 </ b> A later becomes the negative electrode side porous layer 23.

  The first to third green sheets are produced by a known method. For example, a powder of the above solid electrolyte is prepared, and a binder, a solvent, a dispersant, and a plasticizer (and the pore forming agent described above in the case of the second green sheet 22A and the third green sheet 23A) are desired. A slurry is prepared by blending into a composition. Thereafter, the slurry is defoamed, and a ceramic green sheet is produced using a known sheet forming method such as a doctor blade method and a reverse roll coater method.

  Note that the impedance of the dense body 21 increases as the thickness of the dense body 21 increases. Therefore, it is desirable that the first green sheet 21A to be the dense body 21 later be as thin as possible. Specifically, the thickness of the first green sheet 21A is not particularly limited, but is preferably 100 μm or less, and more preferably 50 μm or less.

  On the other hand, the positive electrode side porous layer 22 and the negative electrode side porous layer 23 are both electrodes of the all solid-state lithium secondary battery 10. The battery capacity of the all-solid-state lithium secondary battery 10 increases as the amount of the active material filled in the electrodes (the positive electrode side porous layer 22 and the negative electrode side porous layer 23) of these porous layers increases. Moreover, the positive electrode side porous layer 22 and the negative electrode side porous layer 23 can hold | maintain more active materials, so that each thickness is thick. From the above, it is desirable that the second green sheet 22A to be the positive electrode-side porous layer 22 later and the third green sheet 23A to be the negative electrode-side porous layer 23 later be as thick as possible. Specifically, the thicknesses of the second green sheet 22A and the third green sheet 23A are not particularly limited, but are preferably 10 μm or more, and more preferably 50 μm or more.

<1-2-2. Pressure bonding process>
Next, an adhesive layer (adhesive layer, adhesive paste) is formed by screen printing on the upper and lower surfaces of the first green sheet 21A, the lower surface of the second green sheet 22A, and the upper surface of the third green sheet 23A. . The main component of the adhesive layer is a specific solid electrolyte material contained in the first green sheet 21A (and thus also contained in the second green sheet 22A and the third green sheet 23A). The adhesive layer is produced by kneading a material obtained by adding a binder and a solvent to the solid electrolyte material. For the screen printing of the adhesive layer, a screen printing plate making is used. The screen-printed adhesive layer is heated in an oven with each green sheet and dried.

  In addition, it is not necessary to form the adhesive layer on all the surfaces of the first to third green sheets 21A to 23A that become the bonding surfaces in the next lamination step. That is, the adhesive layer may be formed only on one of the two surfaces that are joined to each other. Therefore, for example, the adhesive layer may be formed only on the upper and lower surfaces of the first green sheet 21A, and is not formed on the upper and lower surfaces of the first green sheet 21A and the lower surface of the second green sheet 22A and the third green sheet. It may be formed only on the upper surface of the sheet 23A.

<1-2-3. Lamination / Pressurization process>
Next, as shown in FIG. 3, the first green sheets 21A are stacked (arranged) so as to be sandwiched between the lower surface of the second green sheet 22A and the upper surface of the third green sheet 23A. That is, these green sheets are laminated so that the upper surface of the third green sheet 23A and the lower surface of the first green sheet 21A are bonded, and the upper surface of the first green sheet 21A and the lower surface of the second green sheet 22A are bonded. To do. Thereby, the precursor of a solid electrolyte structure (structure before filling) is obtained.

  When laminating these green sheets, each green sheet is positioned by a predetermined method. For example, through holes are formed at the four corners of each green sheet, and these green sheets are stacked so that four standing guide pins penetrate the corresponding through holes of each green sheet. As an alternative, markers (marks) are attached to each green sheet, and these green sheets are stacked so that the markers are arranged on a straight line during stacking. Thereby, the relative position shift of each green sheet at the time of lamination | stacking can be suppressed. Thereafter, the stacked first to third green sheets 21A to 23A are pressurized and bonded to each other (pressure bonding).

<1-2-4. Firing step>
The first to third green sheets 21A to 23A (precursor of the solid electrolyte structure (ceramic structure)) laminated in this way are integrally fired at a predetermined firing temperature. The firing temperature and firing time are set to a temperature at which the sintering of the first to third green sheets 21A to 23A sufficiently proceeds (for example, 1090 ° C., 2 hours). As a result, the first green sheet 21A becomes a dense body 21 as shown in FIG. In addition, the pore-forming agent is decomposed and disappears during this firing process. As a result, the second green sheet 22A becomes the positive electrode side porous layer 22 (the positive electrode side porous layer 22 before filling the first active material) having the pores 22a, and the third green sheet 23A has the negative electrode side porous layer 23 having the pores 23a. (The negative electrode side porous layer 23 before filling the second active material). Thus, the pre-filling structure 20B having the same shape as the solid electrolyte structure 20 shown in FIG. 2 is prepared and prepared.

  In addition, when warping or distortion such as undulation is present in the pre-filling structure 20B after firing, the pre-filling structure 20B is heated while applying force (pressure) to the pre-filling structure 20B by a weight or the like, and then fired again. The temperature of the pre-filling structure 20B is increased to a nearby temperature. Thereby, distortion can be corrected.

<2. First placement step>
Next, a first container (first jig) 41 and a second container (second jig) 42 shown in FIGS. 5 and 6A and 6B are prepared.

  The first container 41 is a cylindrical container having a bottom and an open upper surface. The first container 41 is made of ceramics or Teflon (registered trademark). A cylindrical recess 41a having the same diameter as the pre-filling structure 20B and the same height as the pre-filling structure 20B is formed at the bottom of the first container 41. That is, the cylindrical recess 41a is formed in a shape that can just accommodate the pre-filling structure 20B. A plurality of through holes 41b are formed in the bottom (bottom wall) of the cylindrical recess 41a. The diameter of the through hole 41b is not particularly limited, but is 1 mm here. Furthermore, the first container 41 includes a connecting portion 41c that protrudes downward in a cylindrical shape from the bottom wall. The upper surface of the connection part 41c is closed by the bottom wall of the first container 41, and the lower surface is opened. The outer diameter of the connection part 41c is substantially the same as the inner diameter of the cylindrical recess 41a. An O-ring 41d or a rubber plug or the like is fitted on the outer periphery of the connection portion 41c in order to closely contact the second container.

  As shown in FIG. 5, the second container 42 is a truncated cone (conical flask-shaped) container having a bottom and an open upper surface, and is made of glass or plastic. The upper opening of the second container 42 is circular. The inner diameter of the upper opening is slightly smaller than the outer diameter of the O-ring 41d of the connection portion 41c of the first container 41 or the outer diameter of the rubber plug. That is, the connection portion 41 c of the first container 41 is fitted into the upper opening portion of the second container 42. At this time, the side wall of the connection portion 41c and the inner wall of the upper opening portion of the second container 42 are sealed by the O-ring 41d or the rubber plug. In other words, the first container 41 and the second container 42 are connected in an airtight manner and communicate with each other through the through hole 41b. As shown in FIG. 5, the second container 42 includes an air extraction portion 42 a on its side wall. The air extraction part 42a is tubular.

  In the first arrangement step, the first container 41 and the second container 42 are communicated with each other through the through hole 41b and are hermetically connected by an O-ring or a rubber plug. Next, as shown in FIG. 6A, the pre-filling structure 20 </ b> B is inserted and disposed in the cylindrical recess 41 a of the first container 41. At this time, the positive electrode-side porous layer 22 is located above the dense body 21 and the exposed surface of the structure 20B before filling (in this case, the exposed surface that is the lower surface of the negative electrode-side porous layer 23) is the through-hole of the first container 41. The pre-filling structure 20B is arranged in the first container 41 so as to cover 41b.

<3. First filling step>
Next, as shown in FIG. 6A, the prepared first active material dispersion liquid (first fine particle dispersion liquid) SOL <b> 1 is poured into the first container 41. Thereby, the upper surface of the positive electrode side porous layer 22 that is the exposed surface of the positive electrode side porous layer 22 of the structure 20B before filling is exposed in the first active material dispersion liquid SOL1. At this time, the exposed surface of the structure 20B before filling, which is the surface not in contact with the positive electrode-side porous layer 22 of the structure 20B before filling (in this case, exposure of the negative electrode-side porous layer 23 which is the lower surface of the negative electrode-side porous layer 23) Part of the surface is exposed to the space in the second container 42 through the through hole 41b. A seal member such as an O-ring is interposed between the negative electrode-side porous layer 23 of the pre-filling structure 20B and the side wall or bottom surface of the cylindrical recess 41a, so that the first active material dispersion liquid SOL1 is contained in the pre-filling structure 20B. It does not flow between the side surface and the side wall of the cylindrical recess 41a so as to flow into the through hole 41b.

  In this state, the air extraction part 42a of the second container 42 is connected to a pump (decompression device) (not shown), and this pump is driven to lower the atmospheric pressure in the second container 42. That is, the inside of the second container 42 is evacuated. In other words, a pressure difference is generated between the exposed surface side of the positive electrode side porous layer 22 and the lower surface side of the structure 20B before filling (in this case, the exposed surface side of the negative electrode side porous layer 23). As a result, the first active material dispersion liquid SOL1 flows from the exposed surface (upper surface) of the positive electrode side porous layer 22 to the lower surface of the structure 20B before filling (in this case, the negative electrode side porous layer 23, which is the lower surface of the negative electrode side porous layer 23). It passes through the positive electrode side porous layer 22, the dense body 21, and the negative electrode side porous layer 23 until the exposed surface).

  At this time, the first active material dispersed in the first active material dispersion liquid SOL1 passes through the pores 22a from the exposed surface of the positive electrode-side porous layer 22, passes through the upper surface of the dense body 21 (the dense body 21 and the positive electrode-side porous layer). 22, that is, the deep part of the positive electrode-side porous layer 22. As a result, the first active material is filled in the pores 22a. However, as described in the first fine particle dispersion liquid preparation step <1-1-1>, the first active material cannot pass through the pores of the dense body 21. Accordingly, only the materials other than the first active material (liquid such as a solvent and dispersant) contained in the first active material dispersion liquid SOL1 pass through the dense body 21 and the negative electrode-side porous layer 23, and the structure 20B before filling. It reaches the exposed surface of the negative electrode-side porous layer 23 that is the exposed surface. Then, they pass through the through hole 41 b and are stored in the bottom of the second container 42. By continuing such a state for a predetermined time, an appropriate amount of the first active material can be spread evenly throughout the positive electrode side porous layer 22 (inside the pores 22a of the positive electrode side porous layer 22).

<4. First Impurity Removal Step (Positive Electrode-Dense Body Interface Adjustment Step)>
Next, the pre-filling structure 20 </ b> B (hereinafter also referred to as “half-filled structure”) in which the first active material is filled in the pores of the positive electrode-side porous layer 22 is taken out from the first container 41, and its half Heat is applied to the filled structure (heating to raise the temperature). As a result, the positive electrode side porous layer 22 (the pores 22a of the positive electrode side porous layer 22), the dense body 21 and the negative electrode side porous layer 23 are filled in the first active material dispersion liquid SOL1 which is in an undried state. 1 Impurities other than the active material (for example, organic substances such as a solvent) are removed.

<5. Second placement step>
Next, another first container 41 and a second container 42 are prepared. In this case, the first container 41 is also referred to as a “third container” for convenience, and the second container 42 is also referred to as a “fourth container” for convenience. And also in a 2nd arrangement | positioning process, like the 1st arrangement | positioning process, the 1st container 41 and the 2nd container 42 are connected through the through-hole 41b, and are airtightly connected by an O-ring or a rubber plug.

  Next, similarly to the case shown in FIG. 6A, the half-filled structure that has undergone the first impurity removal step is inserted and disposed in the cylindrical recess 41 a of the first container 41. At this time, unlike the first arrangement step, the negative-side porous layer 23 is located above the dense body 21 and the exposed surface of the half-filled structure which is the lower surface of the half-filled structure (in this case, the positive-side porous layer 22 The semi-filled structure is disposed in the first container 41 so that the exposed surface of the first container 41 covers the through hole 41 b of the first container 41.

<6. Second filling step>
Next, the prepared second active material dispersion liquid (second fine particle dispersion liquid) SOL2 is poured into the first container 41. Thereby, the exposed surface of the negative electrode side porous layer 23 of the half-filled structure (the upper surface of the negative electrode side porous layer 23) is exposed in the second active material dispersion liquid SOL2. At this time, the exposed surface of the half-filled structure that is a surface not in contact with the negative-electrode-side porous layer 23 of the half-filled structure (in this case, the exposed surface of the positive-electrode-side porous layer 22 that is the lower surface of the positive-electrode-side porous layer 22) Is exposed to the space in the second container 42 through the through hole 41b. A seal member such as an O-ring is interposed between the positive electrode-side porous layer 22 of the half-filled structure and the side wall or bottom surface of the cylindrical recess 41a so that the second active material dispersion liquid SOL2 is disposed on the side surface of the half-filled structure. It passes between the side walls of the cylindrical recess 41a so as not to flow into the through hole 41b.

  In this state, the air extraction part 42a of the second container 42 is connected to a pump (decompression device) (not shown), and this pump is driven to lower the atmospheric pressure in the second container 42. That is, the inside of the second container 42 is evacuated. In other words, a pressure difference is generated between the exposed surface side of the negative electrode side porous layer 23 and the lower surface side of the half-filled structure (in this case, the exposed surface side of the positive electrode side porous layer 22). Thus, the second active material dispersion liquid SOL2 is exposed from the exposed surface (upper surface) of the negative electrode side porous layer 23 to the lower surface of the half-filled structure (in this case, the positive electrode side porous layer 22 which is the lower surface of the positive electrode side porous layer 22). Through the negative electrode side porous layer 23, the dense body 21 and the positive electrode side porous layer 22.

  At this time, the second active material dispersed in the second active material dispersion liquid SOL2 passes through the pores 23a from the exposed surface of the negative electrode-side porous layer 23 and passes through the upper surface of the dense body 21 (the dense body 21 and the negative electrode-side porous layer). 23, that is, the deep part of the negative electrode-side porous layer 23). As a result, the second active material is filled in the pores 23a. However, as described in the second fine particle dispersion liquid preparation step <1-1-2>, the second active material cannot pass through the pores of the dense body 21. Accordingly, only materials other than the second active material contained in the second active material dispersion liquid SOL2 (liquids such as solvents and dispersants) pass through the dense body 21 and the positive electrode-side porous layer 22 to expose the half-filled structure. It reaches the exposed surface of the positive electrode-side porous layer 22 that is a surface. Then, they pass through the through hole 41 b and are stored in the bottom of the second container 42. By continuing such a state for a predetermined time, an appropriate amount of the second active material can be evenly distributed throughout the negative electrode side porous layer 23 (inside the pores 23a of the negative electrode side porous layer 23).

<7. Second Impurity Removal Step (Positive Electrode-Dense Body Interface Adjustment Step)>
Next, the first active material is filled in the pores 22a of the positive electrode-side porous layer 22, and the second active material is filled in the pores 23a of the negative electrode-side porous layer 23 (hereinafter referred to as “entire structure”). Is also referred to as a “filled structure”) from the first container 41, and heat is applied to the entire filled structure (heating to raise the temperature). As a result, the negative electrode-side porous layer 23 (the pores 23a of the negative electrode-side porous layer 23), the dense body 21, and the positive electrode-side porous layer 22 are filled in the second active material dispersion liquid SOL2 that is in an undried state. 2 Impurities other than the active material (for example, organic substances such as a solvent) are removed.

<8. Production process of positive electrode collector electrode and negative electrode collector electrode>
Finally, the positive electrode collector electrode 31 and the negative electrode collector electrode 32 are respectively formed on the exposed surface of the positive electrode side porous layer 22 and the exposed surface of the negative electrode side porous layer 23 by sputtering. The positive electrode collecting electrode 31 and the negative electrode collecting electrode 32 may be replaced by, for example, a resistance heating vapor deposition method in which a vapor deposition source is heated by resistance and vapor deposition, or an ion beam vapor deposition method in which a vapor deposition source is heated by an ion beam for vapor deposition. Further, it can be formed by a method such as an electron beam evaporation method in which an evaporation source is heated by an electron beam for evaporation. When the obtained all solid state battery is housed in a case or the like, insulation between the positive electrode collecting electrode 31 and the negative electrode collecting electrode 32 is ensured by an appropriate insulating method.

  The above is the manufacturing method of the solid electrolyte structure 20 (the manufacturing method of the ceramic structure, the manufacturing method of the all solid state battery) according to the first embodiment of the present invention. According to this, the fine particle dispersion liquid (first fine particle dispersion liquid SOL1 or second fine particle dispersion liquid SOL2) is formed on the exposed surface side of the porous layer (positive electrode side porous layer 22 or negative electrode side porous layer 23) and before the filling. Due to the pressure difference between the structure and the exposed surface side of the half-filled structure, the structure moves at a relatively high speed from the exposed surface of the porous layer toward the exposed surface of the structure before filling or the half-filled structure. At this time, the fine particle dispersion liquid always exists on the exposed surface side of the porous layer.

  Therefore, the fine particle dispersion liquid passes from the exposed surface of the porous layer to the exposed surface of the pre-filled structure or the semi-filled structure without drying and solidifying in the course of passing through the porous layer. Therefore, the fine particle dispersion liquid (first fine particle dispersion liquid SOL1 or second fine particle dispersion liquid SOL2) is converted into a porous layer (positive electrode side porous layer) by a single filling execution step (first filling execution step or second filling execution step). 22 or the deep part of the negative electrode side porous layer 23). As a result, it is possible to spread an appropriate amount of each fine particle in each porous layer by each filling step. Therefore, the manufacturing time of the all solid state battery 10 can be shortened and the manufacturing cost of the all solid state battery 10 can be reduced.

  Moreover, the said 1st and 2nd filling implementation process is implemented using a simple jig | tool called a 1st container and a 2nd container (or a 3rd container and a 4th container). Therefore, the manufacturing cost of the all solid state battery 10 can be reduced.

  Furthermore, the first fine particle dispersion liquid SOL1 (second fine particle dispersion liquid) filled in the positive electrode side porous layer 22 (negative electrode side porous layer 23) and in an undried state by the first impurity removal step (second impurity removal step). Impurities other than the first fine particles (second fine particles) contained in SOL2) can be removed. Therefore, the high performance all solid state battery 10 can be manufactured.

  In addition, the first green sheet to the third green sheets 21A to 23A contain the same solid electrolyte, and the adhesive layer that pressurizes them is an adhesive layer made of the same solid electrolyte. The problem of reactivity can be reduced. Therefore, they can be fired at an appropriate firing temperature at which sintering can proceed. As a result, since the connection resistance at the connection interface between each electrode and the solid electrolyte can be reduced, a high-performance all solid-state battery 20 can be manufactured.

(Material of solid electrolyte structure)
Next, the material of the solid electrolyte structure 20 will be described. Here, the solid electrolyte structure 20 constitutes the all-solid-state lithium secondary battery 10. Therefore, the following materials suitable for the all solid-state lithium secondary battery 10 can be used. However, the materials listed below are merely examples and are not limited to these.

<Material of solid electrolyte contained in dense body 21>
As the solid electrolyte contained in the ceramics constituting the dense body 21, the following materials containing lithium that becomes mobile ions can be used.
(A1) Li ₃ PO ₄ , Li ₃ PO ₄ , Li ₃ PO ₄ mixed with nitrogen, LiPON, Li ₂ S—SiS ₂ , Li ₂ S—P ₂ S _5, Li ₂ S—B ₂ S _3, etc. Solid electrolyte.
(A2) A lithium ion conductive solid electrolyte doped with lithium halide such as LiI in the material listed in (A1) above, and a lithium oxyacid salt such as Li ₃ PO _{4 in the} material listed in (A1) above. lithium-ion-conducting solid electrolyte _{(e.g., Li 2 S-SiS 2 -Li} 3 PO 4).

(A3) Titanium oxide type solid electrolyte containing lithium, titanium, and oxygen (for example, Li _x La _y TiO ₃ (where x is 0 <x <1, y is 0 <y <1)).
(A4) NASICON type phosphate compound (for example, Li _{1 + x} Al _x Ti _2-x (PO ₄ ) ₃ (where x is 0 <x <1).
The titanium oxide type solid electrolyte and NASICON type phosphoric acid compound shown in the above (A3) and (A4) are more preferable as the material of the dense body 21 because they exhibit stable performance even in firing in an oxygen atmosphere. .

As a more preferable specific example of the solid electrolyte contained in the dense body 21, Li _0.35 La _0.55 TiO ₃ can be mentioned. As described above, in this example, the same solid electrolyte material is used for the dense body 21, the positive electrode side porous layer 22, and the negative electrode side porous layer 23, but these may be different from each other. Further, only two of these (that is, only the dense body 21 and the positive electrode side porous layer 22, only the dense body 21 and the negative electrode side porous layer 23, only the positive electrode side porous layer 22 and the negative electrode side porous layer 23) are present. It may be configured to contain a common solid electrolyte material.

<Material of First Active Material (Active Material Filled in Positive Electrode Side Porous Layer 22, ie, Positive Electrode Active Material)>
The following materials can be used as the first active material.
(B1) Manganese dioxide (MnO ₂ ), iron oxide, copper oxide, nickel oxide, lithium manganese composite oxide (eg, Li _x Mn ₂ O ₄ or Li _x MnO ₂ ), lithium nickel composite oxide (eg, Li _x NiO _2), lithium cobalt composite oxide _(e.g., Li x _{CoO 2),} lithium nickel cobalt composite oxide _{(e.g., LiNi 1-y Co y O} 2), lithium manganese cobalt composite oxide (e.g., LiMn _y Co _{1 -y} O _2), spinel type lithium-manganese-nickel composite oxide _{(e.g., Li x Mn 2-y Ni} y O 4), lithium phosphates having an olivine structure _{(e.g., Li x FePO 4, Li x} Fe 1- _y Mn _y PO ₄ , Li _x CoPO ₄ ), lithium phosphoric acid compound having NASICON structure Products (for example, Li _x V ₂ (PO ₄ ) ₃ ), iron sulfate (Fe ₂ (SO ₄ ) ₃ ), vanadium oxide (for example, V ₂ O ₅ ). In these chemical formulas, x and y are preferably in the range of 0-1.
(B2) A material using two or more of the materials listed in (B1) above.

  The positive electrode-side porous layer 22 can contain a conductive additive as required. For example, there is a technique in which a conductive additive is dispersed in a solution and filled in the porous layer or coated on the surface of the solid electrolyte. Can be mentioned. Examples of the conductive assistant include acetylene black, carbon black, graphite, various carbon fibers, and carbon nanotubes.

More preferable specific examples of the first active material include LiCoO ₂ , Li _x Mn ₂ O ₄ , Li _x MnO ₂ , and Li _x V ₂ (PO ₄ ) ₃ .

<Material of Second Active Material (Active Material Filled in Negative Electrode Side Porous Layer 23, ie, Negative Electrode Active Material)>
The following materials can be used as the second active material.
(C1) Carbon such as graphite carbon, hard carbon, and soft carbon.
(C2) LiAl, LiZn, Li ₃ Bi, Li ₃ Cd, Li ₃ Sd, Li ₄ Si, Li ₄ . Metal compounds such as ₄ Pb, Li _4.4 Sn, and Li _0.17 C (LiC ₆ ).
_{(C3) SnO, SnO 2,} GeO, GeO 2, In 2 O, In 2 O 3, PbO, PbO 2, Pb 2 O 3, Pb 3 O 4, Ag 2 O, AgO, Ag 2 O 3, Sb 2 Metal oxides such as O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , SiO, ZnO, CoO, NiO, TiO ₂ and FeO.

(C4) Li metal compounds such as Li ₃ FeN ₂ , Li _2.6 Co _0.4 N, Li _2.6 Cu _0.4 N, and the like.
(C5) Li metal oxide (including lithium-transition metal composite oxide) such as lithium-titanium composite oxide represented by Li ₄ Ti ₅ O ₁₂ .
(C5) Boron-added carbon such as boron-added carbon and boron-added graphite.
(C6) Graphite.
(C7) A compound having a NASICON structure such as a lithium phosphate compound (for example, Li _x V ₂ (PO ₄ ) ₃ ).
(C8) A material using two or more of the materials listed in (C1) to (C7) above.

  In addition, the negative electrode side porous layer 23 can contain the conductive aid similar to the conductive aid demonstrated in the said positive electrode side porous layer 22 as needed, for example, disperse | distribute a conductive additive in a solution. Examples of the method include filling the inside of the porous layer or coating the surface of the solid electrolyte.

More preferable specific examples of the second active material include Li ₄ Ti ₅ O ₁₂ , TiO _2, and Li _x V ₂ (PO ₄ ) ₃ .

<Another combination of solid electrolyte, first active material and second active material contained in dense body 21>
Furthermore, the solid electrolyte, the first active material, and the second active material contained in the dense body 21 can be made of the following materials.

[1] Solid electrolytes included in the first active material (positive electrode active material) 22b, the second active material (negative electrode active material) 23b, and the dense body 21 are represented by the following general formulas (1) to (3), respectively. material.
M _a N ¹ _b X ¹ _c (1)
M _d N ² _e X ² _f (2)
^{_{M g N 3 h X 3 i}} ... (3)

However, in the general formulas (1) to (3),
M is H, Li, Na, Mg, Al, K, or Ca;
X1, X2 and X3 are at least one polyanion selected from the group consisting of SiO ₄ , PO ₄ , SO ₄ , MoO ₄ , WO ₄ , BO ₄ and BO ₃ ;
a, d and g are numbers from 0 to 5;
b, e and h are numbers from 1 to 2,
c, f, and i are the numbers of 1-3.

Furthermore, in said general formula (1), N1 is at least 1 type selected from the group which consists of a transition metal, Al, and Cu.
In the general formula (2), N2 is at least one selected from the group consisting of transition metals, Al, and Cu.
In the general formula (3), N3 is at least one selected from the group consisting of Ti, Ge, Hf, Zr, Al, Cr, Ga, Fe, Sc and In.

[2] In the general formulas (1) and (2), X1 and X2 contain at least one same polyanion, and in the general formulas (2) and (3), X2 and X3 are the same polyanion. A material containing at least one kind.

[3] The material described in [1] or [2], wherein X1, X2, and X3 in the general formulas (1) to (3) are the first active material 22b and the second active material 23b. And the same material between the solid electrolytes contained in the dense body 21.

[4] The material according to any one of [1] to [3], wherein M in the general formulas (1) to (3) is a first active material 22b, a second active material 23b, and a dense material. A material that is the same between the solid electrolytes contained in the body 21.

[5] The material according to any one of [1] to [4], wherein the skeleton structure of the solid electrolyte contained in the first active material 22b, the second active material 23b, and the dense body 21 is A material having a vertex shared skeleton structure in which X1 in the general formula (1), X2 in the general formula (2), and X3 in the general formula (3) are shared vertices.

[6] The material according to any one of [1] to [5], wherein the solid electrolyte contained in the first active material 22b, the second active material 23b, and the dense body 21 has a NASICON structure. The material that is the body.

[7] When the material according to any one of [1] to [6] is used, the solid electrolyte material is contained in both the positive electrode side porous layer 22 and the negative electrode side porous layer 23. preferable.

  By using the material described in [1] to [7], the all-solid-state lithium secondary battery 10 with high output and long life is provided.

<Material of Positive Electrode Collector 31 and Negative Collector 32>
Examples of materials for the positive electrode collector 31 and the negative electrode collector 32 include platinum (Pt), platinum (Pt) / palladium (Pd), gold (Au), silver (Ag), aluminum (Al), and copper (Cu). And ITO (indium-tin oxide film).

(Second Embodiment)
Next, a manufacturing method of a ceramic structure (solid electrolyte structure) according to a second embodiment of the present invention and an all solid-state lithium secondary battery manufactured by the manufacturing method will be described.

(Construction)
As shown in FIG. 7, this all solid-state lithium secondary battery 50 is only in that the negative electrode side porous layer 23 of the solid electrolyte structure 20 according to the first embodiment is replaced with a negative electrode layer 23 ′ that is not a porous layer. Is different from the all-solid-state lithium secondary battery 10 in FIG. Thus, even when the solid electrolyte structure 20 ′ having the porous layer (in this case, the positive electrode-side porous layer 22) formed only on one surface of the dense body 21 is used, the connection resistance ( Impedance) can be reduced, and good charge / discharge characteristics can be realized. The same applies when only the positive electrode-side porous layer 22 of the solid electrolyte structure 20 is replaced with a positive electrode layer that is not a porous layer.

(Method for producing solid electrolyte structure (ceramic structure) 20 ')
<1. Preparation process>
<1-1. First Fine Particle Dispersion Liquid Preparation Step (First Active Material Dispersion Liquid Preparation Step)>
A first active material dispersion liquid is prepared in the same manner as the first fine particle dispersion liquid preparation step in the first embodiment. As in the first embodiment, the size of the particles containing the first active material in the first active material dispersion solution is smaller than the pores of the positive electrode-side porous layer 22 and larger than the pores of the dense body 21. Thus, the first active material dispersion solution is adjusted.

<1-2. Pre-filling solid electrolyte structure preparation process>
<1-2-1. Green sheet production process>
Next, a laminate (fired body) of the positive electrode-side porous layer 22 and the dense body 21 before being filled with the first active material is formed. More specifically, the first green sheet 21A is prepared, and the second green sheet 22A containing a pore forming agent in a proportion of 50% by volume or more is prepared. The first and second green sheets 21A and 22A are produced by the well-known method described above.

<1-2-2. Pressure bonding process>
Next, the adhesive layer (adhesive layer, adhesive paste) is formed on the upper surface of the first green sheet 21A and the lower surface of the second green sheet 22A by screen printing. The screen-printed adhesive layer is heated in an oven with each green sheet and dried. Note that the adhesive layer may be formed on only one of the upper surface of the first green sheet 21A and the lower surface of the second green sheet 22A, which will be the bonding surface in the next lamination step.

<1-2-3. Lamination / Pressurization process>
Next, the second green sheet 22A is laminated (arranged) on the upper surface of the first green sheet 21A. Thereafter, the first green sheet 21A and the second green sheet 22A that are stacked are pressurized and bonded to each other (pressure bonding).

<1-2-4. Firing step>
The first green sheet 21A and the second green sheet 22A laminated in this way are integrally fired for a predetermined time at a predetermined baking temperature. The firing temperature and firing time are set to temperatures at which the sintering of the first green sheet 21A and the second green sheet 22A proceeds sufficiently (for example, 1090 ° C., 2 hours). In this firing process, the pore-forming agent is decomposed and disappears. As a result, the second green sheet 22A becomes the positive electrode side porous layer 22 having the pores 22a. Hereinafter, the structure in this state is referred to as a “semi-structure” for convenience. The semi-structure is also one of the “pre-fill structures”.

<2. Arrangement process>
Next, the first container 41 and the second container 42 described above are prepared. However, in 2nd Embodiment, the height of the cylindrical recessed part 41a formed in the bottom part of the 1st container 41 is the same as the height of a semi-structure. Next, the 1st container 41 and the 2nd container 42 are connected through the through-hole 41b, and are airtightly connected by O-ring 41d or a rubber stopper.

  Thereafter, the semi-structure is inserted and disposed in the cylindrical recess 41 a of the first container 41. At this time, the positive electrode-side porous layer 22 is located above the dense body 21, and the lower surface of the semi-structure (in this case, the dense body is a surface opposite to the surface on which the positive electrode-side porous layer 22 is formed). The semi-structure is disposed in the first container 41 so that the exposed surface 21 of the first container 41 covers the through hole 41 b of the first container 41.

<3. Filling process>
Next, the prepared first active material dispersion liquid (first fine particle dispersion liquid) SOL 1 is poured into the first container 41. Thereby, similarly to 1st Embodiment, the exposed surface (upper surface of the positive electrode side porous layer 22) of the positive electrode side porous layer 22 is exposed in the 1st active material dispersion liquid SOL1. At this time, a part of the lower surface of the semi-structure (in this case, the exposed surface of the dense body 21) is exposed to the space in the second container 42 through the through hole 41b.

  In this state, the air extraction part 42a of the second container 42 is connected to a pump (decompression device) (not shown), and this pump is driven to reduce the atmospheric pressure in the second container 42, thereby evacuating the second container 42. To do. In other words, the exposed surface side of the positive electrode side porous layer 22 (upper surface side of the positive electrode side porous layer 22) and the exposed surface side of the semi-structure (in this case, the lower surface side of the dense body 21, the exposed surface side of the dense body 21) A pressure difference is produced between the two. Thereby, the first active material dispersion liquid SOL1 passes from the exposed surface of the positive electrode side porous layer 22 to the exposed surface of the semi-structure through the positive electrode side porous layer 22 and the dense body 21.

  At this time, the first active material dispersed in the first active material dispersion liquid SOL1 passes through the pores 22a from the exposed surface of the positive electrode-side porous layer 22, passes through the upper surface of the dense body 21 (the dense body 21 and the positive electrode-side porous layer). 22, that is, the deep part of the positive electrode-side porous layer 22. As a result, the first active material is filled in the pores 22a. On the other hand, the first active material cannot pass through the pores of the dense body 21. Therefore, only those other than the first active material contained in the first active material-dispersed liquid SOL1 (liquids such as solvents and dispersants) pass through the dense body 21 and reach the exposed surface of the semistructure, It passes through the through hole 41 b and is stored in the bottom of the second container 42. By continuing such a state for a predetermined time, an appropriate amount of the first active material is evenly distributed throughout the positive electrode side porous layer 22 (inside the pores 22a of the positive electrode side porous layer 22).

<4. First Impurity Removal Step (Positive Electrode-Dense Body Interface Adjustment Step)>
Next, a semi-structure (hereinafter also referred to as “half-filled half-structure”) in which the first active material is filled in the pores of the positive electrode-side porous layer 22 is taken out from the first container 41 and the half-fill is obtained. Heat is applied to the semi-structure (heated to raise temperature). Thereby, impurities other than the first active material contained in the first active material dispersion liquid SOL1 filled in the positive electrode side porous layer 22 (the pores 22a of the positive electrode side porous layer 22) and the dense body 21 and in an undried state. (For example, organic substances such as a solvent) are removed.

<5. Negative electrode layer 23 'formation process>
On the other hand, a layer to be the negative electrode layer 23 ′ is produced by forming an electrode material containing a negative electrode side active material (second active material) into a thin film or sheet having a predetermined thickness. More specifically, an adhesive paste comprising a negative electrode side active material and a raw material containing only the same solid electrolyte as the solid electrolyte contained in the dense body 21, or a negative electrode side active material and a raw material containing another solid electrolyte, is prepared, The adhesive paste is applied to the exposed surface of the dense body 21 (the surface where the positive electrode side porous layer 22 is not formed), and then the whole is heated and fired. The negative electrode layer 23 ′ may be formed on the lower surface of the dense body 21 by a method such as sputtering, resistance heating vapor deposition, ion beam vapor deposition, or electron beam vapor deposition.

<8. Production process of positive electrode collector electrode and negative electrode collector electrode>
Finally, the positive electrode collector 31 and the negative electrode collector 32 are produced in the same manner as in the first embodiment. The above is the manufacturing method of the solid electrolyte structure 50 according to the second embodiment of the present invention.

  As described above, according to each embodiment of the method for manufacturing a ceramic structure of the present invention, the positive electrode-side porous layer 22 can be filled with the first active material very efficiently, and the negative electrode-side porous layer 23 can be filled with the first active material. Two active materials can be filled. Therefore, it is possible to shorten the manufacturing time of the product using the ceramic structure (or the solid electrolyte structure) and to reduce the manufacturing cost.

  In addition, this invention is not limited to said each embodiment, A various modification can be employ | adopted within the scope of the present invention. For example, the first green sheet 21A, the second green sheet 22A, and the third green sheet 23A described above may contain different solid electrolytes.

  Further, in the filling execution step (first filling execution step, second filling execution step, and filling execution step) of each of the above embodiments, the pressure in the second container 42 is reduced and the inside of the second container 42 is evacuated. It was converted. Instead, the air pressure in the first container 41 may be increased in each filling step.

  That is, as shown in FIG. 8, a first container 41 ′ that replaces the first container 41 and a second container 42 are prepared. In the vicinity of the upper part of the side wall of the first container 41, an air introduction part 41e similar to the air extraction part 42a of the second container 42 is provided. Further, the first container 41 is sealed by a lid body 41f. In other respects, the first container 41 ′ has the same structure as the first container 41. On the other hand, the air extraction part 42a of the second container 42 is kept open.

  And such 1st container 41 'and 2nd container 42 are connected airtightly similarly to said each filling implementation process, and the structure before filling and a half filling structure are carried out to the cylindrical recessed part 41a of 1st container 41'. Insert or place body or semi-structure. Thereafter, an active material dispersion liquid containing an active material to be filled in the pores of the porous layer is placed in the first container 41 ′, and the first container 41 ′ is sealed with a lid 41 f. Next, the air introduction part 41e is connected to a pump (pressure increasing device) (not shown), and the pump is driven to increase the air pressure in the upper part of the first container 41 '(the part not filled with the active material dispersion liquid). Thereby, the pressure difference between the upper surface side (exposed surface side) of the porous layer to be filled with the active material and the pre-filling structure, the half-filled structure, or the lower surface side (exposed surface side) of the half structure. Therefore, the active material dispersion liquid passes through the structure before filling, the half-filling structure, or the half-structure. Therefore, the active material dispersion liquid is uniformly filled into the pores of the porous layer to be filled with the active material in an appropriate amount.

  In each filling step, the first container 41 may be sealed, the air pressure in the first container 41 may be increased, and the air pressure in the second container 42 may be reduced. Further, instead of increasing the atmospheric pressure in the first container 41, the first container 41 is sealed, the first container 41 is filled with the active material dispersion liquid, and the active material dispersion liquid itself is pressurized by a pump or the like. It can also be configured to pump into the first container 41. That is, a pressure larger than the atmospheric pressure in the second container 42 may be applied to the active material dispersion liquid in the first container 41. In addition, when the active material dispersion liquid itself is pressurized with a pump or the like and pumped into the first container 41, the active material in the first container 41 is not damaged so that the first container 41 and / or the structure before filling is not damaged. It is preferable to further provide a relief valve that restricts the liquid pressure of the dispersion liquid to a certain value or less. Moreover, although the 1st container 41 and the 2nd container 42 (3rd container and 4th container) or 1st container 41 'and the 2nd container 42 were mutually separate containers, each was created separately. Then, it may be integrated.

  In addition, as described above, the method for manufacturing a ceramic structure according to the present invention is not limited to the solid electrolyte structure included in the all-solid-state battery described above. For example, a ceramic structure that is a sintered body of a dense body and a porous layer ( Including a solid electrolyte structure), which is also applied to a device in which fine particles are filled in the pores of the porous layer (for example, a ceramic filter or a gas sensor for supporting a catalyst substance in the pores of the porous layer). obtain.

  In addition, in the filling step described above, the exposed surface of the porous layer (the exposed surface of the positive electrode-side porous layer 22 or the exposed surface of the negative electrode-side porous layer 23) is arranged in any direction with respect to the dense body 21 ( Maintained). That is, the exposed surface of the porous layer is, for example, vertically upward and vertically downward with respect to the dense body 21 when the first container 41 and the like are sealed and the fine particle dispersion liquid is filled in the first container 41. They may be arranged diagonally upward, diagonally downward and in the horizontal direction.

It is sectional drawing of the all-solid-state lithium secondary battery manufactured by the manufacturing method of the ceramic structure which concerns on 1st Embodiment of this invention. It is a perspective view of the ceramic structure shown in FIG. It is sectional drawing of the precursor of the ceramic structure shown in FIG. FIG. 2 is a cross-sectional view of the ceramic structure shown in FIG. 1 before being filled with an active material. It is a perspective view of the 1st container and the 2nd container used in the manufacturing method of the ceramic structure concerning a 1st embodiment of the present invention. 6A is a cross-sectional view of the first container shown in FIG. 5, and FIG. 6B is a plan view of the first container. It is sectional drawing of the all-solid-state lithium secondary battery manufactured by the manufacturing method of the ceramic structure which concerns on 2nd Embodiment of this invention. It is a perspective view of the 1st container and the 2nd container used in the manufacturing method of the ceramic structure concerning the modification of the embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... All-solid-state lithium secondary battery, 20 ... Solid electrolyte structure, 20B ... Structure before filling, 21 ... Dense body, 22 ... Positive electrode side porous layer, 23 ... Negative electrode side porous layer, 22a, 23a ... Fine pore ( 22b, 23b ... active material, 21A ... first green sheet, 22A ... second green sheet, 23A ... third green sheet, 31 ... positive electrode collector, 32 ... negative electrode collector, 41 ... first Container, 41a ... cylindrical recess, 41b ... through-hole, 41c ... connection part, 42 ... second container, 42a ... air extraction part.

Claims (11)

A method for producing a ceramic structure having a plate-like dense body made of ceramics and a porous layer made of ceramics fired and integrated on at least one surface of the dense body, wherein the porous layer is filled with fine particles. There,
A fine particle dispersion liquid preparation step for preparing a fine particle dispersion liquid, which is a liquid in which the fine particles are dispersed, and a pre-filling structure for preparing a pre-filling structure that is the ceramic structure before the fine particles are filled in the porous layer A preparation process including a body preparation process;
An arranging step of arranging the pre-filling structure at a predetermined position;
The exposed surface of the porous layer, which is the surface of the porous layer of the structure before filling and is not in contact with the dense body, is exposed in the fine particle dispersion liquid, and the porous layer of the structure before filling Exposing at least a part of the exposed surface of the structure before filling, which is the surface opposite to the exposed surface, to a space, and a predetermined distance between the exposed surface side of the porous layer and the exposed surface side of the structure before filling The fine particle dispersion liquid is caused to pass through the porous layer and the dense body from the exposed surface of the porous layer to the exposed surface of the structure before filling through the pressure difference in the fine particle dispersed liquid. A filling step for filling fine particles in the porous layer;
A method for producing a ceramic structure comprising: In the manufacturing method of the ceramic structure according to claim 1,
The arranging step prepares a first container having a through hole in a part of the bottom and a second container airtightly connected to the first container through the through hole, and the porous layer is the dense body. A step of disposing the structure before filling in the first container so that the exposed surface of the structure before filling covers the through hole,
In the filling step, the fine particle dispersion liquid is stored in the first container, and the air pressure in the second container is decreased and / or the second container is added to the fine particle dispersion liquid in the first container. It is a step of applying a pressure larger than the atmospheric pressure inside,
A method for producing a ceramic structure. The method for producing a ceramic structure according to claim 2, further comprising:
After the completion of the filling step, the ceramic structure is heated to remove impurities other than the fine particles contained in the fine particle dispersion liquid filled in the porous layer and in an undried state. ,
A method for producing a ceramic structure comprising: In the manufacturing method of the ceramic structure as described in any one of Claims 1 thru | or 3,
The ceramic forming the dense body and the porous layer is made of a solid electrolyte,
A method for producing a ceramic structure, wherein the fine particles are electrode active materials used for battery electrodes. In the manufacturing method of the ceramic structure according to claim 4,
The pre-filling structure preparation step includes
A ratio of 50% by volume or more of the pore forming agent in the first green sheet containing the specific solid electrolyte and not containing the pore forming agent, and the green sheet containing the specific solid electrolyte contained in the first green sheet. A second green sheet contained in the first green sheet, and pressurizing the first green sheet and the second green sheet through an adhesive layer made of the same specific solid electrolyte contained in the first green sheet. Bonding and firing the first green sheet and the second green sheet that have been pressure-bonded together,
A method for producing a ceramic structure. A plate-like dense body made of ceramics, and a first porous layer made of ceramics and a second porous layer made of ceramics which are fired and integrated with the dense bodies on the upper and lower surfaces of the dense bodies, respectively. A method for producing a ceramic structure comprising a porous layer filled with first fine particles and the second porous layer filled with second fine particles,
By forming the first porous layer and the second porous layer on the upper and lower surfaces of the dense body by firing, respectively, before the first fine particles are filled in the first porous layer, and the second fine particles A pre-filling structure preparation step of preparing a pre-filling structure that is the ceramic structure before filling the second porous layer;
Preparing a first fine particle dispersion liquid, which is a liquid in which the first fine particles are dispersed so that the first fine particles can pass through the first porous layer and cannot pass through the dense body. Liquid preparation process;
Preparing a second fine particle dispersion liquid, which is a liquid in which the second fine particles are dispersed so that the second fine particles can pass through the second porous layer and cannot pass through the dense body. Liquid preparation process;
A first arrangement step of arranging the pre-filling structure in a first arrangement state;
Exposing the exposed surface of the first porous layer, which is the surface of the first porous layer and is not in contact with the dense body, into the first fine particle dispersion liquid, and the surface of the second porous layer, At least a part of the exposed surface of the second porous layer, which is a surface not in contact with the dense body, is exposed to the space, and between the exposed surface side of the first porous layer and the exposed surface side of the second porous layer By causing a pressure difference in the first porous layer, the first porous layer, the dense body, and the second porous layer are routed from the exposed surface of the first porous layer to the exposed surface of the second porous layer. A first filling execution step of filling the first porous layer with the first fine particles by passing the fine particle dispersion liquid;
A second arrangement step of arranging the pre-filling structure in which the first fine particles are filled in the first porous layer in a second arrangement state;
The exposed surface of the second porous layer is exposed in the second fine particle dispersion liquid, and at least a part of the exposed surface of the first porous layer is exposed to the space, and the same as the exposed surface side of the second porous layer. By creating a pressure difference with the exposed surface side of the first porous layer, the second porous layer, the dense body, and the first porous layer are exposed from the exposed surface of the second porous layer to the exposed surface of the first porous layer. A second filling step of passing the second fine particle dispersion liquid so as to pass through the first porous layer and filling the second fine particle into the second porous layer;
A method for producing a ceramic structure comprising: In the manufacturing method of the ceramic structure according to claim 6,
The first arranging step prepares a first container having a through hole in a part of the bottom and a second container airtightly connected to the first container through the through hole, and the first porous layer. Is disposed above the dense body and the pre-filling structure is disposed in the first container so that the exposed surface of the second porous layer covers the through-hole,
In the first filling step, the first fine particle dispersion liquid is stored in the first container, and the air pressure in the second container is decreased and / or the first fine particle dispersion in the first container is reduced. Applying a pressure to the liquid that is greater than the pressure in the second container;
The second arranging step prepares a third container having a through hole in a part of the bottom and a fourth container airtightly connected to the third container through the through hole, and the second porous layer. Is disposed above the dense body and the pre-filling structure is disposed in the third container so that the exposed surface of the first porous layer covers the through-hole,
In the second filling step, the second fine particle dispersion liquid is stored in the third container, and the atmospheric pressure in the fourth container is decreased and / or the second fine particle dispersion in the third container is reduced. A step of applying a pressure larger than the atmospheric pressure in the fourth container to the liquid,
A method for producing a ceramic structure. A method for producing a ceramic structure according to claim 6 or 7, further comprising:
The first porous layer is filled by heating the pre-filling structure in which the first fine particles are filled in the first porous layer after the first filling step and before the second arranging step. A first impurity removal step of removing impurities other than the first fine particles contained in the first fine particle dispersion liquid that is in an undried state;
A method for producing a ceramic structure comprising: A method for producing a ceramic structure according to any one of claims 6 to 8, further comprising:
After the second filling step, by heating the ceramic structure in which the first fine particles and the second fine particles are filled in the first porous layer and the second porous layer, respectively, A second impurity removal step of removing impurities other than the second fine particles contained in the second fine particle dispersion liquid that is filled and in an undried state;
A method for producing a ceramic structure comprising: In the manufacturing method of the ceramic structure as described in any one of Claim 6 thru | or 9,
The ceramic forming the dense body, the first porous layer and the second porous layer is made of a solid electrolyte,
The first fine particles are any one of a positive electrode active material for forming a positive electrode of a battery and a negative electrode active material for forming a negative electrode of the battery,
The second fine particles are either the positive electrode active material or the negative electrode active material,
A method for producing a ceramic structure. In the manufacturing method of the ceramic structure according to claim 10,
The pre-filling structure preparation step includes
A ratio of 50% by volume or more of the pore forming agent in the first green sheet containing the specific solid electrolyte and not containing the pore forming agent, and the green sheet containing the specific solid electrolyte contained in the first green sheet. The second green sheet contained in the first green sheet, the third green sheet containing the pore forming agent in a proportion of 50% by volume or more in the green sheet containing the specific solid electrolyte contained in the first green sheet, The second green sheet is pressure-bonded to the upper surface of the first green sheet through the adhesive layer made of the specific solid electrolyte contained in the first green sheet, and the adhesive layer is The third green sheet is pressure bonded to the lower surface of the first green sheet, and the first green sheet, the second green sheet, and the third green sheet that have been pressure bonded are integrally fired. Comprising the step of,
A method for producing a ceramic structure.

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