JP2011154902A - All-solid battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an all-solid battery capable of imparting uniform surface pressure to a unit cell without lowering energy density. <P>SOLUTION: The all-solid battery includes at least one unit cell having a solid electrolyte layer existing between a positive electrode layer and a negative electrode layer. The positive electrode layer, the negative electrode layer and the solid electrolyte layer include sulfide based solid electrolyte as electrolyte. In at least one of the positive electrode layer, the negative electrode layer and the solid electrolyte layer, the Young's modulus of the sulfide based solid electrolyte in an outer periphery region of the layer is smaller than the Young's modulus of the sulfide based solid electrolyte in an inside region located inside the outer periphery region. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an all solid state battery.

  In recent years, with the rapid spread of information-related equipment such as personal computers, video cameras, and mobile phones, and communication equipment, development of batteries that are used as power sources has been regarded as important. Also in the automobile industry, development of high-power and high-capacity batteries for electric vehicles and hybrid vehicles is underway. Among various batteries, lithium secondary batteries are attracting attention because of their high energy density and output.

  As a lithium secondary battery using a flammable organic electrolyte as an electrolyte layer disposed between the positive electrode layer and the negative electrode layer, in addition to liquid leakage, safety measures assuming short circuit or overcharge are indispensable. In particular, high-power, high-capacity batteries are required to further improve safety. Therefore, research and development of all-solid-state batteries such as all-solid lithium secondary batteries using non-combustible inorganic solid electrolytes such as sulfide-based solid electrolytes and oxide-based solid electrolytes are being promoted. As the inorganic solid electrolyte, a sulfide-based solid electrolyte such as a sulfide-based glass body or a sulfide-based crystal body has attracted attention from the viewpoint of ion conductivity.

  In an all solid state battery, in order to obtain a desired capacity and voltage, usually, a plurality of unit cells in which a positive electrode layer, a solid electrolyte layer, and a negative electrode layer are arranged in this order are electrically connected. Specifically, a plurality of unit cells in which a positive electrode layer, a solid electrolyte layer, and a negative electrode layer are sequentially stacked are stacked, or an electrode body in which an electrode layer or a solid electrolyte layer is formed on a belt-shaped substrate is wound. Thus, a plurality of single cells can be connected. The unit cell group connected in this way has a binding force to reduce the resistance between the layers constituting the unit cell, the resistance in each layer constituting the unit cell, and the resistance between the unit cells. Added.

The all-solid-state battery has a problem that the surface pressure applied to each layer constituting the unit battery is likely to vary due to the binding force. In particular, in an all-solid battery having a structure in which an insulator is arranged around these electrode layers in order to prevent a short circuit caused by peeling off of the positive electrode layer and the negative electrode layer, the outer periphery and outer periphery of the electrode layer and the solid electrolyte layer Difference in surface pressure is likely to occur between the inside and the inside of the part. The variation in surface pressure causes unevenness in contact resistance and reaction resistance between the respective layers, and as a result, further causes unevenness in battery performance. Moreover, the variation in surface pressure reduces the durability of the battery.
In view of this, various techniques have been proposed in order to eliminate variations in the surface pressure applied to the electrode layer and the solid electrolyte layer. For example, in Patent Document 1, a plurality of bipolar electrodes, each having a positive electrode on one surface and a negative electrode on the other surface, are stacked with a separator interposed between the positive electrodes. A bipolar battery in which a plurality of unit cells constituted by the negative electrode and the separator are laminated, and has a sealing material that surrounds the unit cell and is provided between the current collectors, A bipolar battery is disclosed in which the thickness in the stacking direction of the portion where the positive electrode and the negative electrode are present is equal to or greater than the thickness in the stacking direction of the portion where the sealing material is present.

JP 2006-54119 A

However, since the bipolar battery of Patent Document 1 is provided with a member that does not directly contribute to power generation, the energy density of the battery is reduced.
Further, as a result of the study by the present inventors, when a sulfide-based crystal is used as the inorganic solid electrolyte, the surface pressure acting on each layer of the unit cell varies particularly due to the high hardness of the sulfide-based crystal. It was found easy. Further, the present inventors have found that the durability of the all-solid battery is improved by increasing the surface pressure acting on each layer of the unit cell.

  The present invention has been accomplished in view of the above circumstances, and an object of the present invention is to provide an all solid state battery capable of imparting a uniform surface pressure to a single cell without reducing the energy density.

The all solid state battery of the present invention is an all solid state battery comprising at least one unit cell in which a solid electrolyte layer is interposed between a positive electrode layer and a negative electrode layer, the positive electrode layer, the negative electrode layer, and the solid electrolyte. The layer includes a sulfide-based solid electrolyte as an electrolyte, and at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer has a Young's modulus of the sulfide-based solid electrolyte included in an outer peripheral region of the layer, The Young's modulus of the sulfide-based solid electrolyte contained in the inner region located inside the outer peripheral region is smaller.
As described above, the all solid state battery of the present invention includes a sulfide-based solid electrolyte in which the outer peripheral region has a relatively small Young's modulus and the inner region has a relatively Young's modulus in at least one layer constituting the single cell. Contains a large sulfide-based solid electrolyte. Thus, by reducing the Young's modulus of the outer peripheral region, the surface pressure applied to the outer peripheral region can be increased, and variations in the surface pressure can be reduced.

  As a combination of sulfide-based solid electrolytes having different Young's moduli as described above, for example, the sulfide-based solid electrolyte contained in the outer peripheral region is a sulfide-based glass body, and the sulfide contained in the inner region A combination in which the solid electrolyte is a sulfide crystal is exemplified.

  According to the present invention, in the all-solid-state battery, it is possible to reduce the variation in the surface pressure of the unit cell without reducing the energy density. That is, the present invention contributes to the improvement of durability and power generation performance of the all solid state battery, and further to the increase in capacity.

It is a graph which shows the relationship between the performance deterioration of an all-solid-state battery using a sulfide type solid electrolyte, and surface pressure. It is a disassembled perspective view which shows one example of an all-solid-state battery of this invention. It is a disassembled perspective view which shows the other form of the all-solid-state battery of this invention. It is a graph which shows the surface pressure distribution of an Example and a comparative example.

  The all solid state battery of the present invention is an all solid state battery comprising at least one unit cell in which a solid electrolyte layer is interposed between a positive electrode layer and a negative electrode layer, the positive electrode layer, the negative electrode layer, and the solid electrolyte. The layer includes a sulfide-based solid electrolyte as an electrolyte, and at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer has a Young's modulus of the sulfide-based solid electrolyte included in an outer peripheral region of the layer, The Young's modulus of the sulfide-based solid electrolyte contained in the inner region located inside the outer peripheral region is smaller.

The present inventors have found that, in an all solid state battery using a sulfide-based solid electrolyte, the durability of the all solid state battery is improved by increasing the surface pressure acting on each layer constituting the unit cell ( (See FIG. 1). FIG. 1 shows the durability obtained by applying different surface pressures to a laminated unit cell containing a sulfide-based solid electrolyte (Li ₇ P ₃ S ₁₁ ) in any of a positive electrode layer, a solid electrolyte layer, and a negative electrode layer. It is the result of evaluating. Specifically, the resistance value R0 of the manufactured stacked unit cell is measured, and then a charge / discharge cycle test is performed for about two weeks, and the resistance value R1 of the unit cell after the cycle test is measured, and the deterioration rate is measured. (R1 / R0 × 100%) was calculated.

Further, the present inventors have found that in the surface direction of each layer constituting the unit cell, the surface pressure is low in the outer peripheral region and the surface pressure is high in the inner region (see “Comparative Example” in FIG. 4).
In at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer constituting the unit cell, the Young's modulus in the outer peripheral region of the layer is relatively reduced, and the Young's modulus in the inner region is relatively increased. The present inventors have found that the surface pressure in the outer peripheral region can be increased and the variation in surface pressure can be reduced.

Hereinafter, the all solid state battery of the present invention will be described with reference to FIGS.
FIG. 2 shows an example of the structure of the unit cell in the all solid state battery of the present invention. The unit cell 4 shown in FIG. 2 has a laminated structure in which the positive electrode layer 2, the solid electrolyte layer 1, and the negative electrode layer 3 are laminated in this order. In the positive electrode layer 2, a current collector 5 is disposed on the surface opposite to the solid electrolyte layer 1. In the negative electrode layer 3, a current collector 6 is disposed on the surface opposite to the solid electrolyte layer 1.
In the unit cell 4, the solid electrolyte layer 1 includes an outer peripheral region 1A containing a sulfide-based solid electrolyte having a relatively small Young's modulus, and an inner region 1B containing a sulfide-based solid electrolyte having a relatively large Young's modulus. Consists of. Similarly to the solid electrolyte layer 1, the positive electrode layer 2 and the negative electrode layer 3 are also outer peripheral regions 2 </ b> A and 3 </ b> A containing sulfide-based solid electrolytes having a relatively small Young's modulus, and sulfides having a relatively large Young's modulus. And inner regions 2B and 3B containing a solid electrolyte.

  Here, the outer peripheral region of each layer is a region extending from the outer peripheral edge of the layer toward the central portion of the layer so as to surround the central portion in the plane direction of the layer, and the inner region is surrounded by the outer peripheral region. It is an area including the center in the surface direction. The specific distribution form of each region is not particularly limited, and may be appropriately designed according to the shape of the unit cell, the restraint form, and the like.

  In the present invention, at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer contains a sulfide-based solid electrolyte having a relatively small Young's modulus in the outer peripheral region, and a sulfide-based compound having a relatively large Young's modulus. By including the solid electrolyte in the inner region, the Young's modulus of the outer peripheral region of the layer is relatively reduced, and the Young's modulus of the inner region is relatively increased. As described above, in at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer constituting the unit cell, the variation in the surface pressure can be reduced by distributing the regions having different Young's moduli in the surface direction. In addition, since the Young's modulus of each region is adjusted by a solid electrolyte, the energy density of the battery does not decrease unlike the case where the variation in surface pressure is suppressed using a material that does not directly contribute to power generation.

  In FIG. 2, the outer peripheral region and the inner region containing sulfide-based solid electrolytes having different Young's moduli are distributed in any of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer constituting the unit cell. The layer for distributing the inner region may be any one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer, or may be any two layers. For example, as shown in (3A) to (3C) of FIG. 3, the outer peripheral region 2A and the inner region 2B may be distributed only in the positive electrode layer 2, or the outer peripheral region 1A and the inner region 1B only in the solid electrolyte layer 1. The outer peripheral region 3A and the inner region 3B may be distributed only in the negative electrode layer 3.

Hereinafter, the constituent members of the solid state battery will be described.
The positive electrode layer and the negative electrode layer contain an electrode active material and a sulfide-based solid electrolyte, and contain a conductive additive, a binder, and the like as necessary.
The electrode active material is not particularly limited, and for example, a material that can be used for a lithium secondary battery can be used.

Specifically, as the positive electrode active material, lithium nickel cobalt manganese oxide _{(LiNi x Co 1-y-} x Mn y O 2), lithium cobalt oxide (LiCoO _2), lithium nickelate (LiNiO _2), lithium manganate Lithium transition metal compounds such as (LiMnO ₂ ), iron olivine (LiFePO ₄ ), cobalt olivine (LiCoPO ₄ ), manganese olivine (LiMnPO ₄ ), lithium titanate (Li ₄ Ti ₅ O ₁₂ ), copper schrerel (Cu ₂ Mo ₆ S ₈ ), chalcogen compounds such as iron sulfide (FeS), cobalt sulfide (CoS), nickel sulfide (NiS), and the like.

The negative electrode active material includes lithium transition metal compounds such as lithium titanate (Li ₄ Ti ₅ O ₁₂ ), metal alloys such as La ₃ Ni ₂ Sn ₇ , carbon materials such as hard carbon, soft carbon, and graphite. Can be mentioned.

The sulfide-based solid electrolyte is not particularly limited, and examples thereof include a sulfide-based glass body and a sulfide-based crystal body that can be used as a solid electrolyte of a lithium secondary battery. Specifically, Li ₂ S—P ₂ S ₅ , Li ₂ S—SiS ₂ , Li _3.25 P _0.25 Ge _0.76 S ₄ , Li _4-x Ge _1-x P _x S ₄ , Li ₇ P ₃ S ₁₁ , Examples thereof include glass bodies and crystal bodies such as Li ₂ S—SiS ₂ —Li ₃ PO ₄ . Among these sulfide-based solid electrolytes, Li ₂ S—P ₂ S ₅ , Li ₂ S—SiS ₂ , Li ₂ S—SiS ₂ —Li ₃ PO ₄ , lithium sulfide (Li ₂ S) and other compounds the proportion is not particularly limited, it is generally possible, the molar ratio of Li ₂ S and other compounds (Li ₂ S / other compounds), which is less than 1 to 100 (however, the Li ₂ S + other compound = 100 mol) Is preferred.

  The sulfide-based glass body can be obtained by vitrifying the sulfide-based solid electrolyte raw material by performing mechanical milling treatment or melt quenching treatment. The mechanical milling process is a method of obtaining a glass material by mechanically mixing and grinding raw materials of a sulfide-based solid electrolyte to obtain a glass material, and can be based on a general method. The melt quenching process is also a common glass synthesis method, and can be applied to a general method when employed as a synthesis method of sulfide-based glass.

  The sulfide-based crystal body can be obtained by heat-treating a sulfide-based glass body. Although specific heating temperature is based also on a sulfide type glass body, about 100-400 degreeC may be sufficient normally, Preferably it is 200-300 degreeC. In addition, the crystallization of the sulfide-based glass body is preferably performed under high pressure conditions. Specific pressure conditions are not particularly limited, but may be usually about 0.1 to 5 MPa, and preferably 2 to 4.5 MPa. In addition, the crystallization of the glass body is preferably performed in the above heating temperature range, preferably under the above pressure condition, usually for 0.1 to 5 hours.

Periphery sulfide-based solid electrolyte is contained in the region and the inner region specific Young's modulus of the sulfide-based solid electrolyte to be contained in is not particularly limited, but the Young's modulus E _A sulfide-based solid electrolyte to be contained in the outer peripheral region, it is smaller than the Young's modulus E _B of the sulfide-based solid electrolyte to be contained in the inner area.
Typically, the ratio of the Young's modulus _{E A} sulfide-based solid electrolyte of the peripheral region with respect to the Young's modulus _{E B} of the sulfide-based solid electrolyte of the inner region _(E A / _{E B)} is in the range of 0.01 to 0.8 In particular, it is preferably in the range of 0.05 to 0.5, more preferably in the range of 0.1 to 0.3.

The combination of the sulfide-based solid electrolyte in the outer peripheral region and the sulfide-based solid electrolyte in the inner region is not particularly limited. For example, the sulfide-based glass body as the sulfide-based solid electrolyte in the outer peripheral region, the sulfide-based solid electrolyte in the inner region And sulfide-based crystals.
Among the sulfide-based solid electrolytes, the Young's modulus is different between a sulfide-based glass body and a sulfide-based crystal body obtained by crystallizing the sulfide-based glass body. Specifically, the Young's modulus of sulfide-based glass (Li ₇ P ₃ S ₄ ) is 0.088 GPa, whereas the Young's modulus of sulfide-based crystal (Li ₇ P ₃ S ₁₁ ) is 0. .444 GPa. Such a magnitude relationship of Young's modulus between a glass body and a crystal body obtained by crystallizing the glass body is not limited to Li ₇ P ₃ S ₄ and Li ₇ P ₃ S ₁₁ , but is found in general sulfide-based solid electrolytes. It is a trend.

The ratio of the electrode active material and the sulfide-based solid electrolyte in the positive electrode layer and the negative electrode layer is not particularly limited and can be appropriately determined.
In the present invention, the positive electrode layer and the negative electrode layer may contain a solid electrolyte other than the sulfide-based solid electrolyte, for example, an oxide-based solid electrolyte. Moreover, as a conductive support agent for improving the electroconductivity of a positive electrode layer and a negative electrode layer, acetylene black, carbon fiber, etc. can be mentioned, for example.

The solid electrolyte layer contains at least a sulfide-based solid electrolyte and, if necessary, contains insulating inorganic particles, a binder, and the like.
Although it does not specifically limit as a sulfide type solid electrolyte, The sulfide type glass body and sulfide type crystal body which were illustrated above can be illustrated.
In the present invention, the solid electrolyte layer may contain a solid electrolyte other than the sulfide-based solid electrolyte, for example, an oxide-based solid electrolyte.

  In the unit cell in which the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are arranged in this order, a current collector is usually provided in each of the positive electrode layer and the negative electrode layer. As the current collector, a general metal material such as copper, nickel, silver, SUS, ruminium, aluminum alloy, or the like can be used.

Hereafter, the manufacturing method of the all-solid-state battery of this invention is demonstrated. In addition, the manufacturing method of the all-solid-state battery of this invention is not restricted to the following method.
First, a positive electrode body having a positive electrode layer formed on the current collector surface and a negative electrode body having a negative electrode layer formed on the current collector surface are prepared. The method for forming the positive electrode layer and the negative electrode layer on the surface of the current collector is not particularly limited. For example, an electrode material powder is prepared by dispersing an electrode material powder in which a binder, a conductive additive, etc. are added to an electrode active material and a sulfide-based solid electrolyte, if necessary, in a solvent. The method of apply | coating and drying to the collector surface is mentioned. The solvent for dispersing the electrode material powder is not particularly limited, and examples thereof include heptane, pentane, octane, propane, and butane. Moreover, as a coating method of electrode material slurry, general methods, such as a spray method and a die-coating method, are employable, for example.

  Next, a solid electrolyte layer is formed on the surface of the positive electrode layer of the positive electrode body or the negative electrode layer of the negative electrode body. The method for forming the solid electrolyte on the surface of the positive electrode layer or the negative electrode layer is not particularly limited. For example, a solid electrolyte powder in which a binder or the like is added to a sulfide-based solid electrolyte, if necessary, is dispersed in a solvent to prepare a solid electrolyte slurry, and the solid electrolyte slurry is applied to the surface of the negative electrode layer or the positive electrode layer. The method of apply | coating and drying is mentioned. The solvent for dispersing the solid electrolyte powder is not particularly limited, and examples thereof include heptane, pentane, octane, propane, and butane. Moreover, as a method for applying the solid electrolyte slurry, for example, a general method such as a spray method or a die coating method can be employed.

The positive electrode body with a solid electrolyte layer and the negative electrode body prepared above are laminated, or the positive electrode body and the negative electrode body with a solid electrolyte layer are laminated so that the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are laminated in this order. A single cell is obtained by pressing. The press pressure is not particularly limited, and may usually be about 0.1 to 5 ton / cm ² .

In the manufacturing process of the unit cell, among the positive electrode layer, the negative electrode layer, and the solid electrolyte layer, a layer having an outer peripheral region and an inner region having different Young's moduli can be manufactured, for example, as follows. That is, an electrode material slurry for a peripheral region containing a sulfide-based glass body (relatively low Young's modulus) as a sulfide-based solid electrolyte, and a sulfide-based crystal (relative Young's modulus as a sulfide-based solid electrolyte) A positive electrode layer having an outer peripheral region and an inner region having different Young's moduli, respectively, by preparing each of the electrode material slurries for the inner region containing A negative electrode layer is obtained.
Similarly, a solid electrolyte slurry for an outer peripheral region containing a sulfide-based glass body as a sulfide-based solid electrolyte and a solid electrolyte slurry for an inner region containing a sulfide-based crystal as a sulfide-based solid electrolyte were prepared, respectively. Then, a solid electrolyte layer having an outer peripheral region and an inner region having different Young's moduli can be obtained by applying and drying the respective regions.

Alternatively, an electrode material slurry containing a sulfide-based glass body as a sulfide-based solid electrolyte is uniformly applied to the current collector and dried, and then the region corresponding to the inner region is heated, preferably heated and pressurized. The sulfide glass body in this region can be crystallized to obtain a positive electrode layer and a negative electrode layer having an outer peripheral region and an inner region having different Young's moduli.
Similarly, after uniformly applying and drying a solid electrolyte slurry containing a sulfide-based glass body as a sulfide-based solid electrolyte, the region corresponding to the inner region is heated, preferably heated and pressurized, so that the region can be obtained. The sulfide-based glass body can be crystallized to obtain a solid electrolyte layer having an outer peripheral region and an inner region having different Young's moduli.
Thus, after forming the layer, by crystallizing the sulfide-based glass body in the layer to form regions having different Young's moduli, the state of the unit cell in which the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are laminated Thus, by heating the region corresponding to the inner region, the inner region and the outer peripheral region can be collectively formed on all of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer.

  An arbitrary number of unit cells are usually stacked to produce a solid battery. The unit cells located at both ends of the stacked unit cells are each provided with a negative electrode terminal and a positive electrode terminal, and are accommodated in an arbitrary battery case.

Here, although the solid electrolyte layer is formed on the positive electrode layer or the negative electrode layer, the solid electrolyte layer is formed by applying and drying the solid electrolyte slurry on the surface of a porous substrate such as a nonwoven fabric or glass fiber. It can also be formed. After the solid electrolyte layer formed in this manner is stacked with the positive electrode layer and / or the negative electrode layer, a unit cell can be manufactured by pressing or heating, or pressing and heating (hot pressing).
The positive electrode layer and the negative electrode layer are formed on the current collector by applying electrode material slurry to the surface of the current collector, and are formed on the solid electrolyte by applying electrode material slurry to the surface of the solid electrolyte layer. May be.

Furthermore, the positive electrode layer, the negative electrode layer, and the solid electrolyte layer can also be formed by press-molding electrode material powder or solid electrolyte powder by a powder molding method.
Further, the all solid state battery of the present invention is not limited to a stacked type in which a plurality of unit cells are stacked, but may be a wound type in which a positive electrode layer and a negative electrode layer are wound with a solid electrolyte layer interposed therebetween.

Example 1
<Battery fabrication>
A slurry of a sulfide-based glass body (Li ₂ PS ₄ glass) was prepared, and a solid electrolyte layer body was produced by spray coating on a porous substrate and drying.
On the other hand, a slurry containing a positive electrode active material (LiCoO 2) and a sulfide-based glass body (Li ₂ PS ₄ glass) is prepared, spray coated on the current collector foil, and dried, thereby collecting the current collector foil and the positive electrode layer. The body was made.
Also, a slurry containing a negative electrode active material (graphite) and a sulfide-based glass body (Li ₂ PS ₄ glass) is prepared, spray-coated on the current collector foil, and dried, thereby collecting the current collector foil and the negative electrode layer. The body was made.
Next, the solid electrolyte layer body, the current collector foil-positive electrode layer assembly and the current collector foil-negative electrode layer assembly prepared as described above were arranged such that the current collector foil and the stacking order of each layer were current collector foil-positive electrode layer-solid. After stacking so as to form an electrolyte layer-negative electrode layer-current collector foil, a single battery was produced by pressing.
Subsequently, the center portion in the surface direction of the obtained unit cell was hot-pressed to crystallize the sulfide-based glass body contained in the center portion (inner region) of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer.

<Surface pressure measurement>
About the all-solid-state battery obtained above, the surface pressure sensor was arrange | positioned in the position from which the distance differs from the center of a surface, and surface pressure distribution was evaluated.
The results are shown in FIG.

(Comparative Example 1)
<Battery fabrication>
In Example 1, an all solid state battery was produced in the same manner except that Li ₇ P ₃ S ₁₁ crystal was used as the electrolyte and heat treatment (hot pressing) was not performed on the center of the electrode body.
<Surface pressure measurement>
The surface pressure of the obtained all solid state battery was measured in the same manner as in the example. The results are shown in FIG.

(result)
As shown in FIG. 4, the all-solid-state battery of Example 1 has an increased surface pressure in a region (outer peripheral region) away from the center of the surface compared to the all-solid-state battery of Comparative Example 1, and variations in surface pressure. Reduced. That is, according to the present invention, it was found that variations in surface pressure can be reduced.

1 ... Solid electrolyte layer (1A: outer peripheral region, 1B: inner region)
2 ... Positive electrode layer (2A: outer peripheral region, 2B: inner region)
3 ... negative electrode layer (3A: glass region, 3B: inner region)
4 ... Single cell 5 ... Current collector 6 ... Positive electrode terminal 7 ... Negative electrode terminal

Claims (2)

An all-solid battery comprising at least one unit cell in which a solid electrolyte layer is interposed between a positive electrode layer and a negative electrode layer,
The positive electrode layer, the negative electrode layer, and the solid electrolyte layer include a sulfide-based solid electrolyte as an electrolyte,
In at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer, the Young's modulus of the sulfide-based solid electrolyte included in the outer peripheral region of the layer is included in the inner region located inside the outer peripheral region. An all-solid-state battery characterized by having a Young's modulus smaller than that of the sulfide-based solid electrolyte.   2. The all solid according to claim 1, wherein the sulfide-based solid electrolyte contained in the outer peripheral region is a sulfide-based glass body, and the sulfide-based solid electrolyte contained in the inner region is a sulfide-based crystal. battery.

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