JP2018101467A - Manufacturing method of all-solid battery and all-solid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of all-solid battery capable of improving ion conductivity of a solid electrolyte layer.SOLUTION: A manufacturing method of all-solid battery including a lamination electrode body of integral sintered compact laminating a positive electrode layer, a solid electrolyte layer 1, and a negative electrode layer, includes a solid electrolyte layer sheet manufacturing step of manufacturing a sheet-like solid electrolyte material containing solid electrolyte powder, and a step of manufacturing the lamination electrode body by sintering a lamination clamping the sheet-like solid electrolyte material between a sheet-like negative electrode layer material containing powder of negative electrode active material and powder of solid electrolyte, and a laminar positive electrode layer material containing powder of positive electrode active material and powder of solid electrolyte. In the solid electrolyte layer sheet manufacturing step, powder of first solid electrolyte 10a having particle size of 2.1-2.5 μm, and powder of second solid electrolyte 10b having particle size of 0.18-0.25 μm are used as the powder of solid electrolyte.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an all-solid battery manufacturing method and an all-solid battery.

  Lithium secondary batteries are known for their high energy density among various secondary batteries. However, since lithium secondary batteries that are widely used use flammable organic electrolytes as electrolytes, lithium secondary batteries have stricter safety measures against liquid leakage, short-circuiting, overcharging, etc. than other batteries. It has been demanded. In recent years, therefore, research and development have been actively conducted on all-solid-state batteries using oxide-based or sulfide-based solid electrolytes as electrolytes. Solid electrolytes are mainly composed of ionic conductors that can conduct ions in solids, and in principle, various problems caused by flammable organic electrolytes occur like conventional lithium secondary batteries. do not do. An all-solid battery is an integrated sintered body (hereinafter referred to as a laminated electrode) in which a layered solid electrolyte (solid electrolyte layer) is sandwiched between a layered positive electrode (positive electrode layer) and a layered negative electrode (negative electrode layer). A current collector).

  As a manufacturing method of the laminated electrode body, a method of firing a molded body obtained by pressurizing raw material powder using a mold (hereinafter also referred to as compression molding method) or a method using a known green sheet (hereinafter referred to as green) Sheet method). In the compression molding method, the layered product is fired by filling the raw material powder of each layer of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer into a layer (sheet shape) in a mold and pressing in a uniaxial direction. Thus, a laminated electrode body is obtained.

  In the green sheet method, a slurry-like positive electrode layer material containing a positive electrode active material and a solid electrolyte, a slurry-like negative electrode layer material containing a negative electrode active material and a solid electrolyte, and a slurry-like solid electrolyte layer material containing a solid electrolyte are each sheeted. And forming a sintered body by firing a laminate in which a solid electrolyte layer material green sheet is sandwiched between a positive electrode layer material and a negative electrode layer material green sheet. The solid electrolyte contained in the positive electrode layer and the negative electrode layer (hereinafter collectively referred to as the electrode layer) is coated between the particles of the electrode active material while being coated on the surfaces of the powdered positive electrode active material and the negative electrode active material. It has a function of expressing ionic conductivity in the electrode layer by intervening in the electrode layer.

As the positive electrode active material and the negative electrode active material (hereinafter also collectively referred to as an electrode active material), materials used in conventional lithium secondary batteries can be used. In addition, since an all-solid-state battery does not use a flammable electrolyte, an electrode active material capable of obtaining a higher potential difference has been studied. The solid electrolyte has the formula _{Li a X b Y c P d} O NASICON type oxide-based solid electrolyte represented by _e, as the solid electrolyte of the NASICON type oxide, Patent Document 1 below The described Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ (hereinafter also referred to as LAGP) is well known. Non-Patent Document 1 below outlines all-solid-state batteries.

JP 2013-45738 A

Osaka Prefectural University Inorganic Chemistry Research Group, “Summary of All Solid-State Batteries”, [online], [Search September 8, 2016], Internet <URL: http://www.chem.osakafu-u.ac.jp /ohka/ohka2/research/battery_li.pdf>

  A laminated electrode body, which is a basic configuration of an all-solid battery, includes a sintered body having a structure in which a solid electrolyte layer is sandwiched between a positive electrode layer and a negative electrode layer. A solid electrolyte, which is a characteristic component in an all-solid-state battery, exhibits ionic conductivity by being crystallized by firing. The solid electrolyte is also contained in the electrode layer, and the solid electrolyte in the electrode layer is interposed between the particles of the electrode active material and plays a role of assisting ionic conduction at a very small distance between the particles. . The solid electrolyte layer consisting only of the solid electrolyte is an ion that directly intervenes between the positive electrode layer and the negative electrode layer that are largely separated in the stacking direction as compared to the distance between the electrode active materials in the electrode layer, and directly contributes to the charge / discharge reaction. Has the function of transferring between the positive and negative electrodes. Therefore, the quality of the solid electrolyte layer greatly affects the performance of the all-solid battery. That is, in order to put an all-solid battery into practical use, it is important to improve the ionic conductivity of the solid electrolyte layer.

  Therefore, an object of the present invention is to provide a method for producing an all solid state battery capable of improving the ionic conductivity of the solid electrolyte layer and an all solid state battery provided with a solid electrolyte layer excellent in ionic conductivity.

The present invention for achieving the above object is an integral sintered body, a positive electrode layer containing a positive electrode active material and a solid electrolyte, a solid electrolyte layer containing a solid electrolyte, and a negative electrode active material and a solid. A method for producing an all-solid battery comprising a laminated electrode body in which a negative electrode layer containing an electrolyte is laminated in this order,
A solid electrolyte layer sheet production step of producing a sheet-like solid electrolyte material containing the solid electrolyte powder;
Between the sheet-like negative electrode layer material including the negative electrode active material powder and the solid electrolyte powder, and the layered positive electrode layer material including the positive electrode active material powder and the solid electrolyte powder. Including a firing step of sintering the laminated body obtained by sandwiching the sheet-like solid electrolyte material to produce the laminated electrode body,
In the solid electrolyte layer sheet preparation step, as the solid electrolyte powder, a first solid electrolyte powder having a particle size of 2.1 μm to 2.5 μm and a particle size of 0.18 μm to 0.25 μm A second solid electrolyte powder having
It is set as the manufacturing method of the all-solid-state battery characterized by the above-mentioned.

  In the solid electrolyte layer sheet manufacturing step, the volume ratio V1 / V2 between the volume V1 of the first solid electrolyte in the solid electrolyte material and the volume V2 of the second solid electrolyte is 590 ≦ V1 / V2 ≦ 2679. It is good also as a manufacturing method of the all-solid-state battery to do.

The solid electrolyte is LAGP represented by a general formula Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ , and the laminate is fired at a temperature of 600 ° C. or higher and 650 ° C. or lower in the firing step. It can also be set as the manufacturing method of the all-solid-state battery combined.

  Further, within the scope of the present invention, there is provided an all-solid battery comprising a laminated electrode body made of an integral sintered body in which a layered solid electrolyte is sandwiched between a layered positive electrode and a negative electrode, The solid electrolyte includes a first solid electrolyte particle having a particle size of 2.1 μm or more and 2.5 μm or less, and a second solid electrolyte particle having a particle size of 0.18 μm or more and 0.25 μm or less. An all solid state battery characterized by this is also included. An all-solid battery in which the volume ratio V1 / V2 of the volume V1 of the first solid electrolyte in the layered solid electrolyte and the volume V2 of the second solid electrolyte is 590 ≦ V1 / V2 ≦ 2679 You can also.

  According to the manufacturing method of the all-solid-state battery which concerns on this invention, the ionic conductivity of a solid electrolyte layer can be improved. Moreover, the all-solid-state battery which concerns on this invention is excellent in the ionic conductivity in a solid electrolyte layer.

It is a figure which shows the procedure for producing LAGP contained in the said sintered compact. It is a figure which shows the preparation procedures of the sample using the said LAGP. It is the schematic which shows the structure of the sintered compact produced based on the manufacturing method which concerns on the Example of this invention. It is an electron micrograph of the sample produced based on the manufacturing method which concerns on the said Example. It is an electron micrograph of the other sample produced based on the manufacturing method which concerns on the said Example. It is an electron micrograph of the sample baked at low temperature. It is an electron micrograph of the sample baked at high temperature.

=== Embodiment of the Invention ===
The all solid state battery according to the embodiment of the present invention is characterized in that two types of powdered solid electrolytes having different particle diameters are included in the solid electrolyte layer constituting the laminated electrode body. Therefore, in order to evaluate only the characteristics of the solid electrolyte layer of the all-solid-state battery according to the embodiment of the present invention, a sintered body including only the solid electrolyte layer in which the electrode layer is omitted from the laminated electrode body was manufactured. The procedure for producing the sintered body will be described below as an example.

=== First Embodiment ===
In the manufacturing procedure of the sintered body according to the first example, LAGP is used as the solid electrolyte, and the sintered body is manufactured using the green sheet method. In the procedure for producing the sintered body according to the first example, various sintered bodies having different LAGP particle sizes were produced as samples. And the ionic conductivity of each sample was measured. Below, the preparation procedure of LAGP is demonstrated first, and the preparation procedure of the sample using the LAGP is demonstrated next.

<Preparation of solid electrolyte>
FIG. 1 shows a procedure for producing a ceramic powder made of LAGP included in a sample. First, the powder of Li ₂ CO ₃ , Al ₂ O ₃ , GeO ₂ , NH ₄ H ₂ PO _{4 which} is a raw material of LAGP is weighed to a predetermined composition ratio and mixed with a magnetic mortar or ball mill (s1), The mixture is put in an alumina crucible or the like and pre-baked at a temperature of 300 ° C. to 400 ° C. for 3 hours to 5 hours (s2). The calcined powder obtained by calcining is heat-treated at a temperature of 1200 ° C. to 1400 ° C. for 1 h to 2 h, thereby dissolving the calcined powder (s3). And the powder which consists of amorphous LAGP is obtained by rapidly cooling the melt | dissolved sample and vitrifying (s4). Next, the amorphous LAGP powder is coarsely crushed to a particle size of 200 μm or less (s5), and the coarsely crushed solid electrolyte powder is pulverized using a pulverizer such as a ball mill. Thus, a LAGP powder (hereinafter also referred to as a LAGP powder) having a target particle diameter (median diameter) is obtained (s6).

<Preparation of sintered body>
FIG. 2 is a diagram showing a procedure for producing a sample using the LAGP powder produced by the above procedure by the green sheet method. First, a binder is added in an amount of 20 wt% to 30 wt% with respect to the LAGP powder, and an anhydrous alcohol such as ethanol is added as a solvent in an amount of 30 wt% to 50 wt% with respect to the LAGP powder, and the raw material of the paste-like solid electrolyte layer material is mixed. (S11). At this time, two types of LAGP powders having different particle sizes depending on the sample were included. Here, the ratio of the two types of LAGP having different particle diameters was made equal in mass ratio. In the following, for two types of LAGP, LAGP having a larger particle diameter is referred to as LAGP1, and the smaller particle diameter is referred to as LAGP2.

  The raw material of the solid electrolyte layer material obtained as described above is mixed for 20 h by a ball mill (s12). Thereby, a paste-like solid electrolyte layer material obtained by uniformly mixing the raw materials of the solid electrolyte layer material is obtained. After defoaming the paste-like solid electrolyte layer material in vacuum (s13), the solid electrolyte layer material is coated on a PET film by the doctor blade method to obtain a sheet-like solid electrolyte layer material (s14). ). In order to adjust the thickness of the solid electrolyte layer sheet to a desired thickness, a single sheet of solid electrolyte layer material obtained by one coating is laminated, and the laminated one is press-bonded. Thus, a solid electrolyte layer sheet made of a green sheet is obtained. Here, four sheet-like solid electrolyte layer materials were laminated to obtain a solid electrolyte layer sheet. Next, the solid electrolyte layer sheet was cut into a predetermined plane size (s15). And in order to evaluate the characteristic of only a solid electrode layer, the cut solid electrolyte layer sheet | seat was baked at the temperature of 650 degreeC for 2 hours, and the sample was produced (s16). In an actual all-solid-state battery, green sheets corresponding to the positive electrode layer and the negative electrode layer are prepared, and a laminate in which the solid electrolyte layer sheet is sandwiched between the positive electrode layer and the green sheet of the negative electrode layer and pressed is fired and stacked. An electrode body is produced.

<Sample characteristics>
By the above procedure, various samples having different combinations of particle sizes of LAGP1 and LAGP2 were prepared. The sample is a sheet-like sintered body, and a current collector layer composed of a thin film of gold (Au) is formed on both the front and back surfaces of the sheet by sputtering. Then, the impedance of each sample is measured, and the ion conduction of each sample The degree (S / cm) was determined.

  Table 1 below shows the ionic conductivity of each sample.

As shown in Table 1, samples 1 to 7 having a particle size φ1 of LAGP1 of 2.0 μm and samples 40 to 46 having a particle size φ1 of LAGP1 of 2.6 μm are generally used regardless of the particle size φ2 of LAGP2. It was lower than 1 × 10 ⁻⁵ (S / cm), which is a criterion for determining the quality of ionic conductivity. In Samples 8 to 39 having φ1 of 2.1 μm to 2.5 μm, an ion conductivity of 1 × 10 ⁻⁵ (S / cm) or more was obtained depending on the difference between φ1 and φ2. In Samples 8 to 39, as a whole, it was found that the ionic conductivity tends to decrease regardless of whether the difference between φ1 and φ2 is too large or too small.

From the above, it has been found that if the particle size of LAGP contained in the electrolyte layer is made uniform, it is difficult to obtain high ionic conductivity. That is, ionic conductivity can be improved by mixing two types of LAGP1 and LAGP2 having different particle diameters. It was also found that there was an appropriate numerical range for the particle sizes (φ1, φ2) of LAGP1 and LAGP2. Therefore, in Table 2 below, samples having an ionic conductivity of 1 × 10 ⁻⁵ (S / cm) or more in Table 1 are extracted and shown.

From Table 2, the conditions of the particle diameters (φ1, φ2) of LAGP1 and LAGP2 at which the ion conductivity is 1 × 10 ⁻⁵ (S / cm) or more are such that the particle diameter φ1 of LAGP1 is 2.1 μm ≦ φ1 ≦ 2. In the case of 5 μm, it was found that if the particle diameter φ2 of LAGP2 is 0.18 μm ≦ φ2 ≦ 0.25 μm, the ion conductivity is surely 1 × 10 ⁻⁵ (S / cm) or more. In addition, as a mechanism which improves ionic conductivity by mixing LAGP of a different particle diameter in a solid electrolyte layer, it can be considered as follows.

  When small particles are filled in a limited space, the porosity decreases and the density increases, but the formability for maintaining the shape before sintering is poor. That is, molding defects occur. If a large amount of a substance that does not contribute to ionic conductivity such as a binder is used in order to prevent molding defects, the ionic conductivity naturally decreases. On the other hand, when large particles are used for the solid electrolyte layer, voids between the particles become large, the sinterability is lowered, and the ionic conductivity is also lowered. That is, if the particle size of LAGP is constant, it is difficult to achieve both sinterability and formability.

On the other hand, when two types of LAGP having different particle diameters are mixed in the solid electrolyte layer, as shown in FIG. 3, small solid electrolyte particles 10b are interposed between large solid electrolyte particles 10a that improve moldability. Therefore, the porosity in the solid electrolyte layer 1 is also reduced and the sinterability is improved. That is, the small particles 10b function to enhance the binding property between the large particles 10a. In order to obtain practical ion conductivity, it is necessary to set the respective particle diameters (φ1, φ2) of the large particles 10a and the small particles 10b within appropriate numerical ranges, and the numerical ranges are those described above. 0.1 μm ≦ φ1 ≦ 2.5 μm and 0.18 μm ≦ φ2 ≦ 0.25 μm. FIG. 4 is an electron micrograph showing the sintered state of Sample 27 whose ion conductivity is 1.89 × 10 ⁻⁵ (S / cm) in Tables 1 and 2. As is apparent from the area indicated by the dotted ellipse in the figure, it can be seen that small particles are interposed between large particles.

<About volume ratio>
In the sample preparation procedure described above, LAGP1 and LAGP2 were included in the solid electrolyte at a mass ratio of 50:50. Considering that the ionic conductivity is increased by the mechanism as shown in FIG. 3, the ratio of the occupied volume V1 of LAGP1 and the occupied volume V2 of LAGP2 in the solid electrolyte layer reduces the ionic conductivity. It becomes. Therefore, the ratio V1 / V2 (= φ1 ³ / φ2 ³ ) of the volume V1 of LAGP1 to the volume V2 of LAGP2 was calculated.

  Table 3 below shows the volume ratio V1 / V2 of each sample shown in Table 2 together with the ionic conductivity.

As shown in Table 3, the volume ratio LAGP1 / LAGP2 in the samples 10 to 13, 18 to 21, 26 to 29, and 34 to 37 in which the particle sizes of LAGP1 and LAGP2 are within the appropriate numerical range is 593 vol% to 2679 vol%. It is. And even if a particle diameter is outside an appropriate numerical range, samples 14, 15, 24, 25, 32, and 33 having an ionic conductivity of 1 × 10 ⁻⁵ (S / cm) or more exist. And among the samples whose particle diameter is in the proper numerical range, the volume ratio V1 / V2 of sample 13 is the smallest and is 593 vol%. Of the samples in which the particle sizes of LAGP1 and LAGP2 are outside the proper numerical range, the sample 14 closest to the particle size of this sample 13 also has an ionic conductivity of 1 × 10 ⁻⁵ (S / cm) or more, The volume ratio V1 / V2 of the sample 14 is 527 vol%. Therefore, if the particle diameters of LAGP1 and LAGP2 are within the above-mentioned appropriate numerical range, the lower limit of the volume ratio V1 / V2 for the ionic conductivity conductivity to be 1 × 10 ⁻⁵ (S / cm) or more is at least 527 vol. Since the lower limit of the volume ratio V1 / V2 is set to 590 vol%, the ionic conductivity conductivity is surely 1 × 10 ⁻⁵ (S / cm) or more.

On the other hand, regarding the upper limit of the volume ratio V1 / V2, the sample 34 has the largest volume ratio V1 / V2 of 2679 vol% among the samples whose particle diameters are within the appropriate numerical range. And among the samples in which the particle sizes of LAGP1 and LAGP2 are outside the proper numerical range, the sample 33 closest to the particle size of this sample 24 also has an ionic conductivity of 1 × 10 ⁻⁵ (S / cm) or more, The volume ratio V1 / V2 of the sample 33 is 3180 vol%. Therefore, if the particle diameters of LAGP1 and LAGP2 are within the above-mentioned appropriate numerical range, the upper limit of the volume ratio V1 / V2 is at least in the range of 2679 vol% to 3180 vol%, and therefore the ionic conductivity conductivity is 1 × 10. If the upper limit of the volume ratio V1 / V2 to be ⁻⁵ (S / cm) or more is set to 2679 vol%, the ionic conductivity conductivity is surely 1 × 10 ⁻⁵ (S / cm) or more.

=== Second Embodiment ===
In the production procedure of the sintered body according to the second example, the sintered body is produced in the same manner as in the first example except that the firing temperature is 600 ° C. Various sintered bodies having different LAGP particle diameters were prepared as samples. Table 4 shows the particle sizes of LAGP1 and LAGP2, the ionic conductivity, and the volume ratio V1 / V2 of LAGP1 and LAGP2 in the sample prepared by the procedure of the second example.

As shown in Table 4, the samples 47 to 53 in which the particle diameter φ1 of LAGP1 is 2.0 μm and the samples 86 to 92 in which the particle diameter φ1 of LAGP1 is 2.6 μm are generally used regardless of the particle diameter φ2 of LAGP2. It was lower than 1 × 10 ⁻⁵ (S / cm), which is a criterion for determining the quality of ionic conductivity. Samples 54 to 85 having φ1 of 2.1 μm to 2.5 μm had an ion conductivity of 1 × 10 ⁻⁵ (S / cm) or more depending on the difference between φ1 and φ2. Samples 56 to 59, 64 to 67, 72 to which correspond to the appropriate numerical ranges of φ1 and φ2 defined in the first embodiment, 2.1 μm ≦ φ1 ≦ 2.5 μm, 0.18 μm ≦ φ2 ≦ 0.25 μm The ionic conductivities of 75 and 80 to 83 were all 1 × 10 ⁻⁵ (S / cm) or more. Table 5 shows the ionic conductivity of these samples.

As shown in Table 5, even if the solid electrolyte layer is fired at a low temperature, practical ion conductivity can be obtained as long as it is sintered in a state containing two kinds of solid electrolytes having appropriate particle sizes. I found out that FIG. 5 is an electron micrograph showing the sintered state of Sample 73 having an ionic conductivity of 1.29 × 10 ⁻⁵ (S / cm) in Table 5. As in the electron micrograph shown in FIG. 4, it can be seen that small particles are interposed between large particles.

  Note that LAGP can obtain ionic conductivity by crystallization, but if the calcination temperature is too low and crystallization is insufficient, there is a possibility that practical ionic conductivity may not be obtained. FIG. 6 shows an electron micrograph of the solid electrolyte layer fired at a low temperature of less than 600 ° C. Compared with the crystallized LAGP previously shown in FIGS. 4 and 5, the structure is clearly different, the outer shape of the particles is clear, and amorphous LAGP remains, resulting in insufficient crystallization. You can see that If the firing temperature is too high, the solid electrolyte may foam and voids may be generated in the solid electrolyte layer. FIG. 7 shows an electron micrograph of the solid electrolyte layer fired at 660 ° C. The cavity 20 produced by foaming can be confirmed. Therefore, in an all-solid battery using LAGP as the solid electrolyte, it is desirable that the firing temperature be 600 ° C. or higher and 650 ° C. or lower.

=== Other Embodiments ===
In the above embodiment, LAGP is used as the solid electrolyte, but a solid electrolyte other than LAGP may be used. Then, two types of solid electrolytes having different particle diameters are included in the solid electrolyte, and the volume ratio V1 / V2 described above is added to the above-mentioned volume ratio in addition to the particle sizes φ1, φ2 or φ1 and φ2 of the two types of solid electrolytes. Should be set. Further, the firing temperature may be sintered at an appropriate temperature that is sufficiently crystallized and does not cause foaming.

  The said Example assumes applying to the manufacturing method of the all-solid-state battery using the green sheet method. Of course, as long as the particle diameter of the solid electrolyte powder contained in the solid electrolyte layer is set within the above-described appropriate numerical range, an all-solid battery may be manufactured by a compression molding method.

  In addition, the said embodiment and Example are shown as an example and do not limit the scope of the invention. The above configurations can be implemented in appropriate combination, and various omissions, replacements, and changes can be made without departing from the scope of the invention. The above-described embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof in the same manner as included in the scope and spirit of the invention.

1 solid electrolyte layer, 10a LAGP1 particles, 10b LAGP2 particles,
s11 solid electrolyte mixing step, s14 coating step, s16 firing step

Claims (5)

An integral sintered body in which a positive electrode layer containing a positive electrode active material and a solid electrolyte, a solid electrolyte layer containing a solid electrolyte, and a negative electrode layer containing a negative electrode active material and a solid electrolyte are laminated in this order. A method for producing an all-solid battery comprising a laminated electrode body comprising:
A solid electrolyte layer sheet production step of producing a sheet-like solid electrolyte material containing the solid electrolyte powder;
Between the sheet-like negative electrode layer material including the negative electrode active material powder and the solid electrolyte powder, and the layered positive electrode layer material including the positive electrode active material powder and the solid electrolyte powder. Including a firing step of sintering the laminated body obtained by sandwiching the sheet-like solid electrolyte material to produce the laminated electrode body,
In the solid electrolyte layer sheet preparation step, as the solid electrolyte powder, a first solid electrolyte powder having a particle size of 2.1 μm to 2.5 μm and a particle size of 0.18 μm to 0.25 μm A second solid electrolyte powder having
A method for producing an all-solid battery.   2. The volume ratio V1 / V2 between the volume V1 of the first solid electrolyte and the volume V2 of the second solid electrolyte in the solid electrolyte material is 590 ≦ V1 in the solid electrolyte layer sheet manufacturing step according to claim 1. / V2 ≦ 2679, The manufacturing method of the all-solid-state battery characterized by the above-mentioned. 3. The solid electrolyte according to claim 1, wherein the solid electrolyte is LAGP represented by a general formula of Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ , and is 600 ° C. or higher and 650 ° C. or lower in the firing step. A method for producing an all-solid battery, wherein the laminate is sintered at a temperature.   An all-solid battery comprising a laminated electrode body made of an integral sintered body in which a layered solid electrolyte is sandwiched between a layered positive electrode and a negative electrode, wherein the layered solid electrolyte has a thickness of 2.1 μm or more An all-solid battery comprising: a first solid electrolyte particle having a particle size of 2.5 μm or less; and a second solid electrolyte particle having a particle size of 0.18 μm or more and 0.25 μm or less. .   5. The volume ratio V1 / V2 between the volume V1 of the first solid electrolyte in the layered solid electrolyte and the volume V2 of the second solid electrolyte in the layered solid electrolyte is 590 ≦ V1 / V2 ≦ 2679. All-solid battery characterized by.