JP5846313B2 - Manufacturing method of all solid state battery - Google Patents

Description

  The present invention relates to a method for manufacturing an all-solid battery, and more particularly, to an all-solid battery in which a plurality of single cells having a structure in which a positive electrode layer and a negative electrode layer are stacked via a solid electrolyte layer are stacked and integrated. It relates to a manufacturing method.

  2. Description of the Related Art In recent years, in order to achieve high energy density, a stacked battery (all-solid battery) including a stacked body in which two or more sets (single cells) of a positive electrode, a solid electrolyte, and a negative electrode are stacked and integrated ) Has been proposed.

  And regarding such a laminated battery, Patent Document 1 discloses a method for producing a solid battery by producing a green sheet containing materials such as a solid electrolyte and an electrode, and laminating, press-bonding and firing them. ing.

Specifically, in manufacturing a solid battery including a laminate including a solid electrolyte layer, an active material layer, and a current collector layer,
(A) Dispersing active material powder in a solvent containing a binder and a plasticizer to obtain an active material slurry;
(B) dispersing a solid electrolyte powder in a solvent containing a binder and a plasticizer to obtain a solid electrolyte slurry;
(C) dispersing the current collector powder in a solvent containing a binder and a plasticizer to obtain a current collector slurry;
(D) forming an active material green sheet and a solid electrolyte green sheet using the active material slurry and the solid electrolyte slurry,
(E) A solid electrolyte green sheet is laminated on one surface of the active material green sheet to obtain a first green sheet group, and a current collector green is formed on the other surface of the active material green sheet by using a current collector slurry. Forming a sheet layer to obtain a second green sheet group;
(F) a heating step of heating the second green sheet group at 200 ° C. or more and 400 ° C. or less in an oxidizing atmosphere;
(G) The second green sheet group heated in the heating step is fired at a firing temperature higher than the heating temperature in the heating step in a low oxygen atmosphere, and includes a solid electrolyte layer, an active material layer, and a current collector layer. A firing step to obtain a laminate;
(Patent Document 1, Paragraph 0021).

  And according to the method of this patent document 1, after heating the 2nd green sheet group containing a collector green sheet layer, it bakes with the baking temperature higher than the heating temperature of a heating process further in a low oxygen atmosphere. Therefore, even when the current collector made of a metal material is oxidized in the heating process, it can be reduced in the subsequent firing process, and the internal resistance of the solid state battery can be reduced. ing.

  However, as a result of repeated studies by the inventors of the present invention, when a multi-layered cell in which a plurality of unit cell units each having a single cell structure in which a pair of positive and negative electrode layers are stacked via a solid electrolyte layer is stacked, is fired at once. Due to temperature variations in the furnace and uneven temperature distribution in the multi-layer cell, the unit cells that make up the multi-layer cell cannot be fired uniformly, resulting in unstable characteristics or multiple unit cells It has been found that there is a problem that a solid battery (multi-layered cell) having intended characteristics cannot be obtained by being dragged by unit cells having poor characteristics among the units.

JP 2007-227362 A

  The present invention solves the above-described problems, and provides an all-solid battery that can efficiently produce an all-solid battery having stable characteristics without causing instability of the characteristics due to firing and deterioration of the characteristics. An object is to provide a manufacturing method.

In order to solve the above problems, the method for producing an all-solid battery of the present invention comprises:
A single cell structure in which one positive electrode layer and one negative electrode layer are bonded via a solid electrolyte layer, or two or more of the single cell structures are electrically connected in series or in parallel, and are integrally bonded. Forming a multi-cell structure as a fired cell unit; and
A step B of forming a laminated battery structure in which a plurality of the fired cell units are integrally joined by laminating and firing a plurality of the fired cell units; and
When the firing temperature in the step A is T1, and the firing temperature in the step B is T2, T2 <T1,
In the step B, the calcined cell unit, wherein the firing temperature T2 via an intermediate layer of sintered stacked, is characterized that you fired at T2.

  A plurality of the fired cell units obtained in the process A are stacked through an intermediate layer sintered at the firing temperature T2, and fired at a firing temperature T2 lower than the firing temperature T1 in the process A. The sintered cell unit can be integrally bonded through the intermediate layer without reacting with the intermediate layer. That is, it is possible to obtain a laminated battery structure (all-solid battery) in which the laminated fired cell units are reliably bonded via the sintered intermediate layer.

  Moreover, it is preferable to use the intermediate layer containing the fused glass sintered at the firing temperature T2 as the intermediate layer.

  By using an intermediate layer containing a fused glass that is sintered at a firing temperature T2 as the intermediate layer, a laminated battery structure in which the laminated fired cell units are securely bonded via an intermediate layer having a fusibility. It becomes possible to obtain a body.

Moreover, it is preferable that the fused glass contained in the intermediate layer is at least one selected from the group consisting of borate glass, phosphate glass, and silicate glass, or a glass containing the one kind. .
When the fused glass contained in the intermediate layer is at least one selected from the group consisting of borate glass, phosphate glass, and silicate glass, and a glass containing the one type, a plurality of fired cells The units can be more reliably bonded via the intermediate layer, and the present invention can be further effectively realized.

Moreover, as the intermediate layer, it is preferable to use an intermediate layer containing a conductive paste that is sintered at a firing temperature T2.
By using an intermediate layer containing a conductive paste that is sintered at a firing temperature T2 as the intermediate layer, a laminated battery structure in which the laminated fired cell units are securely bonded via an intermediate layer having fusibility. It becomes possible to obtain a body.

  Moreover, it is preferable that the said electrically conductive paste contained in the said intermediate | middle layer is Ag paste.

  When the conductive paste contained in the intermediate layer is an Ag paste, a plurality of fired cell units can be more reliably bonded via the intermediate layer, and the present invention can be further effectively realized.

Moreover, it is preferable to use the intermediate layer containing the thermosetting resin hardened | cured at the calcination temperature T2 as the said intermediate layer.
By using an intermediate layer containing a thermosetting resin that cures at a firing temperature T2 as the intermediate layer, a laminated battery structure in which the laminated fired cell units are reliably bonded via an intermediate layer having fusibility. It becomes possible to obtain a body.

Moreover, it is preferable that the said thermosetting resin contained in the said intermediate | middle layer is an epoxy resin.
When the thermosetting resin contained in the intermediate layer is an epoxy resin, a plurality of baked cell units can be more reliably bonded via the intermediate layer, and the present invention can be further effectively realized. .

The method for producing the all solid state battery of the present invention comprises:
(A) Single cell structure in which one positive electrode layer and one negative electrode layer are bonded via a solid electrolyte layer, or two or more single cell structures are electrically connected in series or in parallel, and are integrally bonded Forming a multi-cell structure as a fired cell unit; and
And (b) forming a laminated battery structure in which a plurality of the fired cell units are integrally joined by laminating and firing a plurality of fired cell units. After sufficiently expressing the characteristics as a unit, the above-described step B is performed so that a plurality of the fired cell units are joined together, so that an all-solid battery having stable characteristics is reliably manufactured. It becomes possible.
That is, it becomes possible to efficiently manufacture an all-solid-state battery having stable characteristics without causing instability of characteristics or deterioration of characteristics due to batch firing of multi-stacked cells.

  In addition, since the firing temperature T1 in the process A is set higher than the firing temperature T2 in the subsequent process B, the firing is performed under the conditions such that the characteristics as the cell unit are sufficiently developed in the process A. By performing firing at a firing temperature T2 lower than T1 in Step B, it is possible to efficiently and reliably manufacture an all-solid-state battery having stable properties without impairing the properties of individual cell units expressed in T1. It becomes possible. That is, in the process B, since a high-temperature thermal history higher than the firing temperature T1 of the process A is not given, the high characteristics of the individual baked cell units expressed in the process A are maintained as they are. As a result, it is possible to obtain an all-solid battery having excellent characteristics.

  A plurality of the fired cell units obtained in the process A are stacked through an intermediate layer sintered at the firing temperature T2, and fired at a firing temperature T2 lower than the firing temperature T1 in the process A. The sintered cell unit can be integrally bonded through the intermediate layer without reacting with the intermediate layer. That is, it is possible to obtain a laminated battery structure (all-solid battery) in which the laminated fired cell units are reliably bonded via the sintered intermediate layer.

It is a figure explaining the structure of the unbaking laminated body for single cells (1st unbaking cell unit) and its manufacturing method in embodiment of this invention. It is a figure explaining the structure of the unbaking laminated body for multiple cells (2nd unbaking cell unit) in the embodiment of this invention, and its manufacturing method. In embodiment of this invention, it is a figure explaining the structure of the unbaked laminated body for multiple cells (3rd unbaked cell unit) produced for the comparison, and its preparation method. It is a figure which shows the structure of the 1st baking completed cell unit produced in embodiment of this invention. It is a figure which shows the structure of the 2nd baking completed cell unit produced in embodiment of this invention. In embodiment of this invention, it is a figure which shows the structure of the 3rd baking completed cell unit produced for the comparison. In embodiment of this invention, it is a figure explaining the method of laminating | stacking and baking the 1st baking completed cell unit. It is a figure which shows the structure of the laminated battery structure (all-solid-state battery) produced in embodiment of this invention. In embodiment of this invention, it is a figure explaining the method of laminating | stacking and baking the 2nd baking completed cell unit. It is a figure which shows the structure of the other laminated battery structure (all-solid-state battery) produced in embodiment of this invention.

Embodiments of the present invention will be described below, and the features of the present invention will be described in detail.
In this embodiment, an all-solid battery (laminated battery structure) including four single cell structures in which a negative electrode layer and a positive electrode layer are stacked via a solid electrolyte layer is used as a requirement of the present invention. The characteristics of the all-solid battery obtained by the method provided and the method not provided with the requirements of the present invention (method of simultaneously firing a multi-layer cell) were examined.

[Preparation of slurry]
First, each material shown in Table 1 was prepared as a material for forming a solid electrolyte, a positive electrode layer, a negative electrode layer, an internal electrode layer, and an intermediate layer.

(1) As a material for a solid electrolyte, a material containing a crystal phase having a NASICON structure having a composition of Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ was prepared.
(2) As a positive electrode material, a powder having a crystal structure of Li ₃ V ₂ (PO ₄ ) ₃ was prepared.
(3) Carbon powder C was prepared as a material used for the positive electrode, the negative electrode, the internal electrode, and the intermediate layer.
(4) Anatase-type titanium oxide (TiO ₂ ) was prepared as a negative electrode material.
(5) As an internal electrode material, a glass ceramic powder having a composition of Li _1.0 Ge _2.0 (PO ₄ ) ₃ was prepared.
(6) As an intermediate layer material, a fused glass having a composition of Na ₂ O.ZnO.B ₂ O ₃ was prepared.
(7) Ag paste was prepared as an intermediate layer material.
This Ag paste is a conductive paste in which Ag particles, epoxy resin, and terpineol are mixed at a weight ratio of 90: 4: 6.

  Then, predetermined materials are combined from the materials shown in Table 1 as shown in Table 2, and are blended at a blending ratio as shown in the blending ratio column of Table 2, so that a solid electrolyte layer, a positive electrode layer, a negative electrode layer, an internal The main material of the electrode layer and the intermediate layer was used. And the slurry for solid electrolyte layers, the slurry for positive electrode layers, the slurry for negative electrode layers, the slurry for internal electrode layers, and the slurry for intermediate | middle layers were produced with the following method.

Each main material (see Table 2) of the solid electrolyte layer, the positive electrode layer, the negative electrode layer, the internal electrode layer, and the intermediate layer shown in Table 2 is blended with polyvinyl acetal resin and alcohol (ethanol) at a weight ratio of 15: 140. Then, a solid electrolyte layer slurry, a positive electrode layer slurry, a negative electrode layer slurry, an internal electrode layer slurry, and an intermediate layer slurry 1 were prepared by mixing with an organic vehicle prepared by dissolution.
Further, an Ag paste having the composition shown in Table 1 was prepared as the intermediate layer slurry 2 in Table 2.

  In addition, each said slurry mix | blends each above-mentioned main material (refer Table 2) and an organic vehicle in the weight ratio of main material 100: organic vehicle 155 (polyvinyl acetal resin 15, alcohol 140), respectively, and it puts in a pot with a medium. After enclosing and rotating on a pot rack, the medium was taken out.

[Production of green sheets]
The slurry of each material and the intermediate layer conductive paste (Ag paste) prepared as described above were each applied onto a polyethylene terephthalate (PET) film using a doctor blade method and heated to 40 ° C. By drying on a hot plate, a green sheet having a thickness of 10 μm, that is, a solid electrolyte layer sheet, a positive electrode layer sheet, a negative electrode layer sheet, an internal electrode layer sheet, and an intermediate layer sheet was prepared. That is, as the intermediate layer sheet, there are two types of intermediate layer sheets: an intermediate layer sheet formed using the above-described intermediate layer slurry 1 and an intermediate layer sheet formed using the intermediate layer slurry 2. Produced.

  In this embodiment, the intermediate layer sheet using the fused glass contains carbon powder that is a conductive material, and in the laminated battery structure (all solid state battery) 100 manufactured through the firing step. The intermediate layer 40A (see FIG. 8, FIG. 10, etc.) functions as an intermediate layer having conductivity. Further, the intermediate layer formed using the intermediate layer sheet using Ag paste also contains Ag as a conductive component and functions as an intermediate layer having good conductivity.

[Preparation of unfired cell unit]
(1) Production of single-cell unfired laminate (first unfired cell unit) Solid electrolyte layer sheet, positive electrode layer sheet, negative electrode layer sheet, internal electrode layer sheet, and intermediate layer sheet, respectively Cut into a square with a side of 25 mm to produce a plurality of lamination sheets.

Then, as shown in FIG. 1, one sheet for internal electrode layer 1 for lamination, one sheet for negative electrode layer 2, five sheets for solid electrolyte layer 3, two sheets for positive electrode layer 4, Each sheet of the internal electrode layer sheets 1 was laminated in the order of one sheet to form a laminate.
In addition, lamination | stacking of each sheet | seat was performed by repeating the operation | movement which peels from a PET film, after each sheet | seat was pressurized and pressure-bonded on 60 degreeC temperature conditions.

  Next, this laminated body was isostatically pressed at 180 MPa by an isostatic press to produce a single-cell unfired laminate (first unfired cell unit) 10.

(2) Production of Unsintered Laminate for Multiple Cells (Second Unsintered Cell Unit) Each green sheet corresponding to two of the above-described first unsintered cell units 10 is stacked and stacked as described below. Formed body. That is, as shown in FIG. 2, one sheet for internal electrode layer 1, one sheet for negative electrode layer 2, five sheets for solid electrolyte layer 3, two sheets for positive electrode layer 4, and an internal electrode layer After laminating each sheet in the order of one sheet 1, the lamination cycle was repeated once again to form a laminate.

  Here again, the lamination of the sheets was performed by repeating the operation of peeling the sheets from the PET film after pressurizing and pressing the sheets under a temperature condition of 60 ° C.

  Next, this laminated body was isostatically pressed at 180 MPa by an isostatic press to produce a multi-cell unfired laminate (second unfired cell unit) 20.

  As shown in FIG. 2, the second unsintered cell unit 20 has a structure in which two unsintered laminated bodies (first unsintered cell units) 10 (see FIG. 1) for single cells are stacked in series. ing.

(3) Production of unsintered laminate for multiple cells (third unsintered cell unit) Further, the green sheets corresponding to four of the above-described first unsintered cell units 10 are stacked as described below. Thus, a laminate was formed. That is, as shown in FIG. 3, one sheet for internal electrode layer 1, one sheet for negative electrode layer 2, five sheets for solid electrolyte layer 3, two sheets for positive electrode layer 4, two internal electrode layers After laminating each sheet in the order of one sheet 1, the lamination cycle was repeated three times to form a laminate.

  Here again, the lamination of the sheets was performed by repeating the operation of peeling the sheets from the PET film after pressurizing and pressing the sheets under a temperature condition of 60 ° C.

Next, this laminated body was subjected to isostatic pressing at 180 MPa by isostatic pressing to produce an unfired laminated body (third unfired cell unit) 30 for a plurality of cells.
As shown in FIG. 3, the third unsintered cell unit 30 has a structure in which four unsintered stacked bodies for single cells (unsintered cell units) 10 (see FIG. 1) are stacked in series. .

  And in this embodiment, the above-mentioned first, second, and third unsintered cell units 10, 20, 30 of the first laminated internal electrode layer sheets (the lower side in FIGS. 1, 2, and 3) The side of the internal electrode layer sheet 1) was the negative electrode side, and the last laminated internal electrode layer sheet (the lower internal electrode layer sheet 1 in FIGS. 1, 2, and 3) 1 was the positive electrode side.

[Baking of unfired cell unit (step A)]
The first green cell unit 10 (FIG. 1), the second green cell unit 20 (FIG. 2), and the third green cell unit 30 (FIG. 3) produced as described above are each formed into a square having a side of 10 mm. It cut | disconnected and stood on the porous setter, and baked. This firing step corresponds to “Step A” in the present invention.

In this step A, each unfired cell unit 10, 20, 30 is baked at 500 ° C. in an N ₂ atmosphere containing 5% by volume of oxygen to remove the polyvinyl acetal resin, and then in an N ₂ atmosphere. Is fired at 700 ° C. to obtain a fired cell unit as shown in FIGS. 4, 5, and 6, that is, a first fired cell unit (single cell structure) 10A (FIG. 4), second A fired cell unit (multiple cell structure) 20A (FIG. 5) and a third fired cell unit (multiple cell structure) 30A (FIG. 6) were obtained.

The first fired cell unit (single cell structure) 10A includes the above-described internal electrode layer sheet 1, negative electrode layer sheet 2, solid electrolyte layer sheet 3, positive electrode layer sheet 4, and internal electrode layer sheet. 1 is a sintered body obtained by firing each sheet (see FIG. 1) laminated in the order of 1. As shown in FIG. 4, an internal electrode layer 1A, a negative electrode layer 2A, a solid electrolyte layer 3A, and a positive electrode layer 4A And a single cell structure including the internal electrode layer 1A.
Further, the second fired cell unit (multiple cell structure) 20A includes two single cell structures 10A, and the third fired cell unit (multiple cell structure) 30A includes the single cell. Four structures 10A are provided.

  Note that the third fired cell unit 30A (FIG. 6) obtained by firing the third unfired cell unit 30 (FIG. 3) has already been laminated and integrally joined by four single cell structures 10A at this stage, It is a laminated battery structure (4 laminated solid battery) having a structure connected in series.

[Lamination and firing of fired cell units (step B)]
(1) Stacking and firing of first fired cell unit 10A As shown in FIG. 7, four first fired cell units (single cell structures) 10A obtained by firing first unfired cell unit 10 are provided. The intermediate layer sheet cut to have the same planar dimensions as the first fired cell unit 10A (the intermediate layer sheet formed using the intermediate layer slurry 1 in Table 2 or the intermediate layer slurry 2 in Table 2) Intermediate layer sheet 40), sandwiched from above and below by a pair of porous setters 50, and fired at 500 ° C. under a pressure of 5 kg / cm ² . That is, in this firing step, firing was performed at a firing temperature of 500 ° C. (T2) lower than the firing temperature of 700 ° C. (T1) in Step A described above. Note that this step of firing at a firing temperature of 500 ° C. (T2) lower than the firing temperature of 700 ° C. (T1) in Step A corresponds to “Step B” in the present invention.

  As a result, as shown in FIG. 8, the four fired cell units (single cell structures) 10 </ b> A have the intermediate layer 40 </ b> A having conductivity using the intermediate layer sheet made of the intermediate layer slurry 1 of Table 2. A laminated battery structure (all solid battery) 100 laminated through the intermediate layer 40A having conductivity using the intermediate layer sheet comprising the intermediate layer slurry 2 of Table 2 Two types of stacked battery structures (all solid state batteries) 100 (all solid state batteries) are obtained.

(2) Lamination and firing of second fired cell unit 20A As shown in FIG. 9, the second fired cell unit (two single cell structures are laminated) obtained by firing the second unfired cell unit 20 The intermediate layer sheet formed by using the two intermediate cell sheets 20A and the same planar dimensions as the second fired cell unit 20A (the intermediate layer sheet 1 shown in Table 2). ), And sandwiched between a pair of porous setters 50 from above and below, and fired at 500 ° C. under a pressure of 5 kg / cm ² . That is, in this step B, baking was performed at a baking temperature of 500 ° C. lower than the baking temperature of 700 ° C. in step A. This step corresponds to “Step B” in the present invention.
As a result, as shown in FIG. 10, two second fired cell units (multiple cell structures) 20 </ b> A are conductive intermediate layers using the intermediate layer sheet made of the intermediate layer slurry 1 of Table 2. A laminated battery structure (all-solid battery) 100 laminated through 40A is obtained.

In addition, there is no special restriction | limiting in the method of bonding 1st baked cell unit 10A and 2nd baked cell unit 20A through the sheet | seat 40 for intermediate | middle layers, For example, instead of using the sheet | seat for intermediate | middle layers as mentioned above In addition, a slurry containing an intermediate layer material (a fused glass having a composition of Na ₂ O · ZnO · B ₂ O ₃ ) is screen-printed on the first fired cell unit 10A or the second fired cell unit 20A. Then, the first fired cell units 10A or the second fired cell units 20A may be bonded to each other before drying.

  Alternatively, a very small amount of the binder solution may be applied to the first baked cell unit 10A or the second baked cell unit 20A, and then bonded through the intermediate layer sheet 40.

[Evaluation of characteristics]
(1) Charge / Discharge Test (a) The structure shown in FIG. 8 was prepared by laminating and firing the first sintered cell unit (single cell structure) 10A of (1) above in Step B. 4 stacked all solid state battery (sample No. 1 sample of Table 3 (sample using the intermediate layer sheet comprising the intermediate layer slurry 1 of Table 2 as the intermediate layer sheet)),
(B) A four-layer all-solid battery having the structure shown in FIG. 10, produced by laminating and firing the second fired cell unit (multiple cell structure) 20A of (2) above in step B. Sample No. 2 in Table 3),
(C) A third unfired cell unit 30 having a structure in which four unfired laminates (unfired cell units) 10 for single cells described above are laminated and fired and sintered in the above-mentioned step A, A four-layer all-solid battery for comparison having the structure shown in FIG. 6 and manufactured without going through the process B of the invention (sample No. 3 in Table 3)
(D) A four-stacked all-solid battery having the structure shown in FIG. 8 produced by laminating and firing the first sintered cell unit (single cell structure) 10A of (1) in Step B above. (Sample No. 4 in Table 3 (Sample using an intermediate layer sheet comprising the intermediate layer slurry 2 in Table 2 as the intermediate layer sheet))
A charge / discharge test was conducted for each of the above.

  The charge / discharge test was carried out by charging to 12.4 V with a current of 20 μA, holding at 12.4 V for 10 hours, leaving it for 3 hours, and discharging to 0 V at 20 μA.

(2) Evaluation Results Table 3 shows the discharge capacities of the four types of four-layer all-solid batteries (a), (b), (c), and (d) described above.

  As shown in Table 3, the samples Nos. 1, 2 and 4 produced by the method according to the embodiment of the present invention have good discharge capacities of 195 μAh, 173 μAh and 211 μAh, respectively, and the process A Samples Nos. 1 and 4 having a smaller number of stacks in (the first cell unit is fired by firing the single cell structure in Step A) are the samples of Sample No. 2 having the larger number of layers in Step A In step A, it was confirmed that the multiple cell structures for two single cell structures were fired to form a second fired cell unit.

In the above embodiment, sodium borate glass (Na ₂ O · ZnO · B ₂ O ₃ ) containing zinc oxide is used as the fusion glass contained in the intermediate layer. There is no restriction, and various compositions can be appropriately selected in consideration of the firing temperature.

For example, as fused glass, soda lime glass, potash glass, borate glass, borosilicate glass, borosilicate barium glass, borate sulfite glass, barium borate glass, bismuth borosilicate glass At least one selected from the group consisting of bismuth zinc borate glasses, bismuth silicate glasses, phosphate glasses, aluminophosphate glasses, and phosphate nitrite glasses can be used.
As for the glass material, at least one selected from the group consisting of SiO ₂ , B ₂ O ₃ , P ₂ O ₅ and GeO _{2 is} used as the network forming oxide, and Li _{2 is} used as the network modifying oxide. At least one selected from the group consisting of O, Na ₂ O, K ₂ O, MgO, CaO, SrO, and BaO, and as intermediate oxides, Al ₂ O ₃ , TiO ₂ , ZnO, ZrO ₂ , and it may be at least one selected from the group consisting of Bi ₂ O _3.
In addition, the fused glass may be a glass ceramic that includes a crystalline phase, or may be a crystallized glass that precipitates a crystalline phase upon firing in Step B.

Moreover, in the said embodiment, although the paste containing Ag was used as an electrically conductive paste contained in an intermediate | middle layer, there is no restriction | limiting in particular in the kind of metal used as an electroconductive component, and various metals are considered in consideration of baking temperature. It can be selected as appropriate.
For example, as the metal for the conductive component used in the conductive paste, at least one of Cu, Fe, Au, Pt, and Pd, a mixture, or an alloy thereof can be used.

Moreover, in the said embodiment, although the epoxy resin was used as a thermosetting resin (thermosetting resin contained in Ag paste) contained in an intermediate | middle layer, there is no special restriction | limiting in the kind of thermosetting resin, and baking Various thermosetting resins can be appropriately selected in consideration of the temperature.
For example, as a thermosetting resin, phenol resin, urea resin (urea resin), melamine resin, unsaturated polyester resin, polyimide resin, diallyl phthalate resin, silicon resin, polyamino bismaleimide resin, casein resin, furan resin, polyurethane resin, At least one of alkyd resins or a mixture thereof can be used.

At this time, in addition to the thermosetting resin, by including insulating particles such as alumina in the intermediate layer, the thermosetting resin softens in the temperature rising process up to the firing temperature T2, and the shape of the intermediate layer becomes It is preferable that it can be prevented from collapsing.

Furthermore, the material used for the intermediate layer is not limited to a combination of a metal and a thermosetting resin, and a material combining a metal and a fused glass can also be used.
The material used for the intermediate layer is not limited to a material combining a metal and a thermosetting resin, or a material combining a metal and a fused glass, and a continuous metal film can be used as it is. For example, it is also possible to use a metal foil or a metal deposition film.

  Moreover, although the said embodiment demonstrated taking the case where the intermediate | middle layer for joining a cell unit (single cell structure or multiple cell structure) has electroconductivity as an example, an insulating thing is used as an intermediate | middle layer. It is also possible to use.

  In that case, an example of an all solid state battery having a structure in which a pair of single cell structures (first fired cell units) are stacked via an insulating intermediate layer will be described. Connecting member (conductive wire, etc.) between the positive electrode layer of the single cell structure on one side and the positive electrode layer of the single cell structure on the other side of the pair of single cell structures (first sintered cell unit) ), And similarly, the negative electrode layer of the single-cell structure on one side and the negative-electrode layer of the single-cell structure on the other side are connected by a connecting member, so that two single-cell structures (first sintered) An all solid state battery having a structure in which cell units) are electrically connected in parallel can be obtained.

  Further, in the above embodiment, in the all solid state battery shown in FIG. 10, the plurality of cell structures have a structure in which two single cell structures are electrically connected in series. A configuration is also possible.

The present invention is not limited to the above embodiment in other points, and various applications and modifications can be made within the scope of the invention.
For example, a specific configuration of a plurality of cell structures formed by combining single cell structures (a connection mode in a case where a plurality of single cell structures are connected in series or in parallel to form a plurality of cell structures), Various applications and modifications can be made with respect to a specific configuration of a laminated battery structure in which a single cell structure or a plurality of cell structures are joined via an intermediate layer.

DESCRIPTION OF SYMBOLS 1 Sheet | seat for internal electrode layers 2 Sheet | seat for negative electrode layers 3 Sheet | seat for solid electrolyte layers 4 Sheet | seat for positive electrode layers 10 Unbaked laminated body for single cells (1st unbaked cell unit)
10A First fired cell unit (single cell structure)
20 Unfired laminate for multiple cells (second unfired cell unit)
20A Second fired cell unit (multiple cell structure)
30 Unfired laminate for multiple cells (third unfired cell unit)
30A Second sintered cell unit 40 Intermediate layer sheet 40A Intermediate layer 50 Setter 100 All solid state battery

Claims (7)

A single cell structure in which one positive electrode layer and one negative electrode layer are bonded via a solid electrolyte layer, or two or more of the single cell structures are electrically connected in series or in parallel, and are integrally bonded. Forming a multi-cell structure as a fired cell unit; and
A step B of forming a laminated battery structure in which a plurality of the fired cell units are integrally joined by laminating and firing a plurality of the fired cell units; and
When the firing temperature in the step A is T1, and the firing temperature in the step B is T2, T2 <T1,
Wherein in step B, the calcined cell unit, wherein the firing temperature T2 via an intermediate layer of sintered stacked, method for manufacturing an all-solid battery characterized that you fired at T2. Wherein the intermediate layer, which comprises using an intermediate layer comprising a fusion glass sintered at a firing temperature T2, method for manufacturing an all-solid-state cell according to claim 1, wherein. The fused glass contained in the intermediate layer is at least one selected from the group consisting of borate glass, phosphate glass, and silicate glass, or is a glass containing the one kind. The manufacturing method of the all-solid-state battery of Claim 2 . Wherein the intermediate layer, which comprises using an intermediate layer comprising a conductive paste is sintered at a sintering temperature T2, method for manufacturing an all-solid-state cell according to claim 1, wherein. The method for manufacturing an all solid state battery according to claim 4 , wherein the conductive paste contained in the intermediate layer is an Ag paste. Wherein the intermediate layer, which comprises using an intermediate layer comprising a thermosetting resin which cures at a firing temperature T2, method for manufacturing an all-solid-state cell according to claim 1, wherein. The method for producing an all solid state battery according to claim 6 , wherein the thermosetting resin contained in the intermediate layer is an epoxy resin.

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