JP2011187370A - All solid battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an all solid battery in which an increase of resistance in the interface of an active material and a solid electrolyte material is effectively controlled. <P>SOLUTION: The all solid battery is provided with an electrode active material layer having an active material, a first solid electrolyte material which contacts the active material, has an anion component different from the anion component of the active material, and is a single-phase electronic-ion mixed conductor, and a second solid electrolyte material which contacts the first solid electrolyte material, has an anion component same as the first solid electrolyte material, and is an ion conductor having no electron conductivity. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an all solid state battery in which an increase in resistance at an interface between an active material and a solid electrolyte material is effectively suppressed.

  With the rapid spread of information-related equipment and communication equipment such as personal computers, video cameras, and mobile phones in recent years, the development of batteries (eg, lithium batteries) that are excellent as power sources has been regarded as important. In fields other than information-related equipment and communication-related equipment, for example, in the automobile industry, development of lithium batteries and the like used for electric cars and hybrid cars is being promoted.

  Here, since a commercially available lithium battery uses an organic electrolyte solution that uses a flammable organic solvent, it has a structure to prevent the installation of a safety device and to prevent a short circuit. Improvements in materials are necessary. In contrast, an all-solid-state battery in which the liquid electrolyte is changed to a solid electrolyte does not use a flammable organic solvent in the battery, so the safety device can be simplified, and the manufacturing cost and productivity are considered excellent. Yes.

  In the field of all solid state batteries, there have been attempts to improve the performance of all solid state batteries by focusing attention on the interface between the active material and the solid electrolyte material. For example, Patent Document 1 discloses an all-solid lithium secondary battery using an electron-lithium ion mixed conductor as a solid electrolyte material in an electrode layer. This technology makes it easy to advance the electrode reaction at the interface between the active material and the solid electrolyte material by adding a mixed conductor having not only ionic conductivity but also electron conductivity to the electrode layer. It is a plan to make it.

  Moreover, in patent document 2, it is the all-solid-state lithium battery using the lithium ion conductive solid electrolyte which mainly has sulfide, Comprising: The all-solid-state lithium which coat | covered the surface of the positive electrode active material with the lithium ion conductive oxide A battery is disclosed. This technique suppresses the formation of a high resistance layer that occurs at the contact interface between the sulfide solid electrolyte and the positive electrode active material.

JP 2001-006674 A WO2007 / 004590

  Although attempts have been made to focus on the interface between the active material and the solid electrolyte material as described above, it has been insufficient to suppress the increase in interface resistance due to the generation of the high resistance layer. The present invention has been made in view of the above circumstances, and a main object of the present invention is to provide an all-solid battery that effectively suppresses an increase in resistance at the interface between the active material and the solid electrolyte material.

  In order to solve the above-mentioned problems, the present inventors have conducted extensive research and as a result, by considering both the potential difference and the chemical potential difference, it is possible to effectively suppress an increase in resistance at the interface between the active material and the solid electrolyte material. As a result, the present invention has been completed.

  That is, in the present invention, an active material, a first solid electrolyte material that is in contact with the active material, has an anion component different from the anion component of the active material, and is a single-phase electron-ion mixed conductor; An electrode active material layer having a second solid electrolyte material that is in contact with the first solid electrolyte material, has the same anion component as the first solid electrolyte material, and is an ionic conductor having no electronic conductivity An all-solid battery is provided.

  According to the present invention, the anion component of the active material is different from the anion parts of the first solid electrolyte material and the second solid electrolyte material, and the anion parts of the first solid electrolyte material and the second solid electrolyte material are the same. In addition, by using an electron-ion mixed conductor for the first solid electrolyte material, it is possible to effectively suppress an increase in resistance at the interface between the active material and the solid electrolyte material.

  Further, in the present invention, an all-solid battery having a positive electrode active material layer, a negative electrode active material layer, and a solid electrolyte layer formed between the positive electrode active material layer and the negative electrode active material layer, At least one of the positive electrode active material layer and the negative electrode active material layer has an anion component that is in contact with the active material and is different from the anion component of the active material, and is a single-phase electron-ion mixed conductor The solid electrolyte layer is in contact with the first solid electrolyte material, has the same anion component as the first solid electrolyte material, and has no ion conductivity. An all-solid battery comprising a second solid electrolyte material as a body is provided.

  According to the present invention, the anion component of the active material is different from the anion parts of the first solid electrolyte material and the second solid electrolyte material, and the anion parts of the first solid electrolyte material and the second solid electrolyte material are the same. In addition, by using an electron-ion mixed conductor for the first solid electrolyte material, it is possible to effectively suppress an increase in resistance at the interface between the active material and the solid electrolyte material.

  In the above invention, the first solid electrolyte material preferably covers the active material. This is because the contact between the active material and the second solid electrolyte material can be effectively prevented.

  In the above invention, the first solid electrolyte material preferably forms a layered structure at the contact surface with the solid electrolyte layer. This is because the contact between the active material and the second solid electrolyte material can be effectively prevented.

  In the above invention, it is preferable that the anion component of the active material, the anion component of the first solid electrolyte material, and the anion component of the second solid electrolyte material are all chalcogens. This is because the range of material selection is wide.

  In the above invention, the active material is an oxide active material in which the anion component is oxygen, and the first solid electrolyte material and the second solid electrolyte material are sulfide solid electrolyte materials in which the anion component is sulfur. It is preferable that This is because a high-capacity and high-power all-solid battery can be obtained.

  In the above invention, the first solid electrolyte material is preferably crystalline. This is because the composition fluctuation is smaller than that of an amorphous solid electrolyte material, and it is easy to perform ionic conduction and electronic conduction through the same path.

In the above invention, the first solid electrolyte material is preferably Li ₂ ZrS ₃ .

  In the above invention, the surface of the active material is coated with a third solid electrolyte material that has the same anion component as the anion component of the active material and is a single phase electron-ion mixed conductor, and the active material and It is preferable that the first solid electrolyte material is in contact with the third solid electrolyte material. It is because it can suppress that an active material and a solid electrolyte material react, and a high resistance layer is produced | generated.

  The all solid state battery of the present invention has an effect of effectively suppressing an increase in resistance at the interface between the active material and the solid electrolyte material.

It is explanatory drawing which shows an example of the electric power generation element of the all-solid-state battery of this invention. It is a schematic diagram explaining the interface state of an active material and a solid electrolyte material. It is a schematic sectional drawing explaining the relationship between an active material, a 1st solid electrolyte material, and a 2nd solid electrolyte material. It is explanatory drawing which shows the other example of the electric power generation element of the all-solid-state battery of this invention. It is explanatory drawing which shows the other example of the electric power generation element of the all-solid-state battery of this invention. It is the result of XRD measurement on the _Li 2 ZrS ₃ obtained in Synthesis Example. It is a schematic sectional drawing explaining the measuring method of Li ion conductivity. It is a result of the XRD measurement with respect to the sulfide solid electrolyte material obtained by the reference example. It is a result of Li ion conductivity and electronic ion conductivity of the battery for evaluation obtained in the reference example.

  Hereinafter, the all solid state battery of the present invention will be described in detail.

  The all solid state battery of the present invention can be roughly divided into two embodiments. Hereinafter, in the all solid state battery of the present invention, the electrode active material layer includes an active material, a first solid electrolyte material and a second solid electrolyte material (first embodiment), and the electrode active material layer includes an active material and The description will be divided into an embodiment (second embodiment) containing the first solid electrolyte material and the solid electrolyte layer containing the second solid electrolyte layer.

1. 1st embodiment 1st embodiment of the all-solid-state battery of this invention has an anion component different from the anion component of the active material and the said active material, and the said active material, and a single phase electron-ion mixing A first solid electrolyte material that is a conductor, and a second solid electrolyte that is in contact with the first solid electrolyte material, has the same anion component as the first solid electrolyte material, and has no electronic conductivity And an electrode active material layer having a material.

  FIG. 1 is an explanatory diagram illustrating an example of a power generation element of the all solid state battery according to the first embodiment. 1 includes a positive electrode active material layer 1, a negative electrode active material layer 2, a solid electrolyte layer 3 formed between the positive electrode active material layer 1 and the negative electrode active material layer 2, and Have Furthermore, the positive electrode active material layer 1 contains an active material 4, a first solid electrolyte material 5 in contact with the active material 4, and a second solid electrolyte material 6 in contact with the first solid electrolyte material 5. The first solid electrolyte material 5 has an anion component different from the anion component of the active material 4. For example, the active material 4 is an oxide active material (an anion component is O), and the first solid electrolyte material 5 is a sulfide solid electrolyte material (an anion component is S). Furthermore, the first solid electrolyte material 5 is a single-phase electron-ion mixed conductor having electron conductivity and ion conductivity. On the other hand, the second solid electrolyte material 6 has the same anion component as the first solid electrolyte material 5. For example, the case where both the first solid electrolyte material 5 and the second solid electrolyte material 6 are sulfide solid electrolyte materials (the anion component is S) is applicable.

  Next, the effect of this embodiment will be described with reference to FIG. FIG. 2 is a schematic diagram illustrating an interface state between the active material and the solid electrolyte material. In FIG. 2, a 4V class oxide active material is considered. Note that FIG. 2 shows the case where the potential of the active material is higher than the potential of the solid electrolyte material, but the same is true even if the potential is reversed.

  FIG. 2A illustrates a conventionally assumed interface state between an active material and a solid electrolyte material, and is a combination of an oxide active material and a sulfide solid electrolyte material. This sulfide solid electrolyte material is an ionic conductor that does not have electronic conductivity, because it is conventionally made of the same material as the insulating material used for the solid electrolyte layer. Therefore, a potential difference (electrochemical stress) occurs at the interface between the oxide active material and the sulfide solid electrolyte material, and the reaction between the two is promoted by this potential difference, which is a major factor in generating a high resistance layer.

  FIG. 2B illustrates an interface state between the active material and the solid electrolyte material assumed in Patent Document 2 described above. The oxide active material, the oxide solid electrolyte material, and the sulfide solid electrolyte are illustrated in FIG. Combination with material. Further, the oxide solid electrolyte material and the sulfide solid electrolyte material are ion conductors having no electronic conductivity. In this case, as in FIG. 2A, a potential difference occurs at the interface between the oxide active material and the oxide solid electrolyte material. However, since both are common to oxides, the chemical potential difference is relaxed, and there is an advantage that the reaction between the two hardly occurs even if there is a potential difference. Moreover, since there is little potential difference at the interface between the oxide solid electrolyte material and the sulfide solid electrolyte material, there is also an advantage that the reaction between the two hardly occurs. However, in FIG. 2B, since the surface of the oxide active material is covered with an oxide solid electrolyte material having no electron conductivity, there is a drawback that the electron conduction path between the active materials is easily cut. .

  FIG. 2 (c) illustrates the interface state between the active material and the solid electrolyte material assumed by the present inventors for comparison. The oxide active material, the oxide solid electrolyte material, and the sulfide solid It is a combination with an electrolyte material. The difference from FIG. 2B is that an electron-ion mixed conductor having electron conductivity and ion conductivity is used as the oxide solid electrolyte material. In this case, since the oxide solid electrolyte material has electronic conductivity, no potential difference occurs at the interface between the oxide active material and the oxide solid electrolyte material. In addition, since the surface of the oxide active material is covered with an oxide solid electrolyte material having electron conductivity, the electron conduction path between the active materials is easily maintained, and the defect of FIG. it can. However, there is a drawback in that a potential difference is generated at the interface between the oxide solid electrolyte material and the sulfide solid electrolyte material, and the reaction between both is promoted by the potential difference, and deterioration is likely to occur.

  In contrast to FIGS. 2 (a) to 2 (c), FIG. 2 (d) explains the interface state between the active material and the solid electrolyte material assumed in this embodiment, and an oxide active material, This is a combination of a sulfide solid electrolyte material and a sulfide solid electrolyte material. The sulfide solid electrolyte material located in the center of FIG. 2D is an electron-ion mixed conductor having electron conductivity and ion conductivity, and corresponds to the first solid electrolyte material in this embodiment. Moreover, the sulfide solid electrolyte material located on the right side of FIG. 2D is an ionic conductor having no electronic conductivity, and corresponds to the second solid electrolyte material in the present embodiment. In this case, since the sulfide solid electrolyte material has electronic conductivity, a potential difference does not occur at the interface between the oxide active material and the sulfide solid electrolyte material. Furthermore, since the surface of the oxide active material is covered with the sulfide solid electrolyte material having electron conductivity, the electron conduction path between the active materials is easily maintained. On the other hand, a potential difference occurs at the interface between the two oxide solid electrolyte materials. However, since both are common to sulfides, the chemical potential difference is relaxed, and even if there is a potential difference, the reaction between the two hardly occurs. Therefore, the combination in this embodiment has an advantage that all the defects in the cases of FIGS. 2A to 2C can be eliminated.

  Thus, according to this embodiment, the anion component of the active material is different from the anion portion of the first solid electrolyte material and the second solid electrolyte material, and the first solid electrolyte material and the second solid electrolyte material By using the same anion part and using an electron-ion mixed conductor for the first solid electrolyte material, an increase in resistance at the interface between the active material and the solid electrolyte material can be effectively suppressed. In addition, for example, even if the Li ion conductivity of the first solid electrolyte material is lower than the Li ion conductivity of the second solid electrolyte material, the second solid electrolyte material having a high Li ion conductivity exhibits Li ion conductivity. By carrying it, it is possible to easily achieve high output.

Further, it is considered that the first solid electrolyte material in the present embodiment needs to have the same ion conduction path and electron conduction path. This is because, if the two are different, it is possible that the electrochemical stress in the ion conduction path cannot be relieved, so that a high resistance layer is formed at the interface and the output is reduced. Therefore, in this embodiment, it is considered that the ion conduction path and the electron conduction path need to be the same. Furthermore, if the first solid electrolyte material is a single phase, the ion conduction path and the electron conduction path are the same. Here, “single phase” means that there are no two or more phases contributing to ionic conduction or electronic conduction. Therefore, even if the first solid electrolyte material includes an impurity phase (for example, a ZrO ₂ phase of a synthesis example described later), if the impurity phase does not contribute to ionic conduction and electronic conduction, the first The solid electrolyte material can be determined as a single phase.

  Whether or not the first solid electrolyte material is a single phase can be determined as follows. That is, when the first solid electrolyte material is a single-phase crystalline material, the crystal structure is specified by X-ray diffraction, and if there are no more than two phases contributing to ionic conduction or electronic conduction in the crystalline structure, It can be determined that the phase is crystalline. On the other hand, when the first solid electrolyte material is a single-phase amorphous material, it can be confirmed that the first solid electrolyte material is a single-phase amorphous material by performing structural analysis using XAFS, TEM, Raman spectroscopy, NMR, or the like. .

Further, in Patent Document 1 described above, a sulfide-based electron-lithium ion mixed conductor is disclosed, but this is different in ion conduction path and electron conduction path as judged from the result of a reference example described later. It is thought to be a thing. Therefore, the electron-lithium ion mixed conductor in Patent Document 1 is not a single-phase compound, and is different from the electron-ion mixed conductor (first solid electrolyte material) in this embodiment.
Hereinafter, the all solid state battery of this embodiment will be described for each configuration.

(1) Electrode active material layer The electrode active material layer in this embodiment contains the active material, 1st solid electrolyte material, and 2nd solid electrolyte material which are mentioned later. Further, the electrode active material layer in this embodiment may be a positive electrode active material containing a positive electrode active material or a negative electrode active material layer containing a negative electrode active material, and may be a positive electrode active material layer and a negative electrode active material layer. Both of the material layers may be used. Especially, in this embodiment, it is preferable that an electrode active material layer is a positive electrode active material layer. This is because there are many types of oxide active materials and the like useful as the positive electrode active material, and the effects of this embodiment are easily exhibited.

(I) Active material The active material in this embodiment may be a positive electrode active material or a negative electrode active material. Moreover, the active material in this embodiment has a cation component and an anion component. Here, the cation component of the active material means an element that can take a positive valence among the elements constituting the active material. On the other hand, the anion component of the active material refers to an element that can take a negative valence among the elements constituting the active material. For example, in LiCoO ₂ , Li and Co are cation components and O is an anion component. The anionic component of the active material in this embodiment is preferably mainly composed of chalcogen. Examples of the chalcogen include oxygen, sulfur, selenium, etc. Among them, oxygen and sulfur are preferable, and oxygen is particularly preferable. That is, it is preferable that the anion component of the active material in this embodiment is mainly oxygen.

Examples of the active material having an anion component mainly composed of oxygen include an oxide active material. The kind of oxide active material can be suitably selected according to the kind of all-solid-state battery. For example, when the all solid state battery is an all solid state lithium battery, as the oxide active material used, the general formula Li _x M _y O _z (M is a transition metal element, x = 0.02 to 2.2, y = 1-2, z = 1.4-4) can be exemplified. In the above general formula, M is preferably at least one selected from the group consisting of Co, Mn, Ni, V, Fe and Si, and is at least one selected from the group consisting of Co, Ni and Mn. It is more preferable. Specific examples of such an oxide active material include LiCoO ₂ , LiMnO ₂ , LiNiO ₂ , LiVO ₂ , LiNi _1/3 Co _1/3 Mn _1/3 O ₂ , LiMn ₂ O ₄ , Li (Ni it can be mentioned _{0.5 Mn 1.5) O 4, Li} 2 FeSiO 4, Li 2 MnSiO 4 , and the like. The oxide active material may be a spinel type active material or a rock salt type active material.

As another example of an active material having an anionic component mainly composed of oxygen, a phosphoric acid-based active material can be given. The type of the phosphoric acid active material can be appropriately selected according to the type of the all solid state battery. For example, when the all solid state battery is an all solid state lithium battery, olivine type active materials such as LiFePO ₄ and LiMnPO ₄ can be exemplified as the phosphoric acid active material used.

The active material in this embodiment may be an active material having an anionic component mainly composed of sulfur. Examples of such an active material include a sulfide active material. Examples of the sulfide active material include S, TiS ₂ , Cu ₂ Mo ₆ S _{8 and the} like.

  Examples of the shape of the active material include a particle shape, and among them, a spherical shape or an elliptical shape is preferable. Moreover, when an active material is a particle shape, it is preferable that the average particle diameter exists in the range of 0.1 micrometer-50 micrometers, for example. The content of the active material in the electrode active material layer is, for example, preferably in the range of 1% by weight to 90% by weight, and more preferably in the range of 10% by weight to 80% by weight.

(Ii) First Solid Electrolyte Material The first solid electrolyte material in the present embodiment is a single phase electron-ion mixed conductor having a cation component and an anion component. The anion portion of the first solid electrolyte material is different from the anion portion of the active material. Here, the cation component of the solid electrolyte material refers to an element that can take a positive valence among the elements constituting the solid electrolyte material. On the other hand, the anion component of the solid electrolyte material refers to an element that can take a negative valence among the elements constituting the solid electrolyte material. For example, in Li ₂ ZrS ₃ , Li and Zr are cation components, and S is an anion component. The anion component of the first solid electrolyte material in this embodiment is preferably mainly composed of chalcogen. Examples of the chalcogen include oxygen, sulfur, selenium, etc. Among them, oxygen and sulfur are preferable, and sulfur is particularly preferable. That is, it is preferable that the anion component of the first solid electrolyte material in this embodiment is mainly composed of sulfur.

Examples of the first solid electrolyte material having an anion component mainly composed of sulfur include a sulfide solid electrolyte material. The type of the sulfide solid electrolyte material can be appropriately selected according to the type of the all-solid battery. For example, when the all-solid battery is an all-solid lithium battery, the sulfide solid electrolyte material (electron-Li ion mixed conductor) includes a Li element, a fourth-period or fifth-period metal element, and an S element. It is preferable to have. The metal element of the fourth period or the fifth period is not particularly limited as long as it is an element capable of obtaining an electron-ion mixed conductor, but for example, Zr, Mo, Sn, Sb, W, Bi, etc. Among them, Zr, Mo, Sb, and Bi are preferable. Specific examples of such a sulfide solid electrolyte material include Li ₂ ZrS ₃ , Li ₂ Mo ₆ S ₈ , LiSbS ₂ , and LiBiS ₂ .

In addition, the first solid electrolyte material in the present embodiment may have an anion component mainly composed of oxygen. Examples of the first solid electrolyte material include an oxide solid electrolyte material. For example, in the system using the sulfide active material described above, it is effective to use an oxide solid electrolyte material as the first solid electrolyte material. Oxide solid electrolyte material - The (electron ion mixed conductor), for _example, a _{xLi 3 PO 4 · (100-} x) Li 3 VO 4 (10 ≦ x ≦ 70) or the like.

  The first solid electrolyte material may be crystalline or amorphous. The difference between crystalline and amorphous can be judged by X-ray diffraction (XRD). This is because, when the first solid electrolyte material is crystalline, the composition fluctuation is small compared to the amorphous solid electrolyte material, and ionic conduction and electronic conduction can be easily performed in the same path. Furthermore, it has an advantage that ion conductivity and electronic conductivity tend to be higher than those of an amorphous solid electrolyte material. Conversely, when the first solid electrolyte material is amorphous, it is softer than the crystalline solid electrolyte material, so that the active material can be expanded and contracted, and the cycle characteristics can be improved. Have advantages.

The first solid electrolyte material preferably has high ionic conductivity. The ionic conductivity of the first solid electrolyte material at room temperature is, for example, preferably 1 × 10 ⁻¹⁰ S / cm or more, more preferably 5 × 10 ⁻¹⁰ S / cm or more. It is preferable that the electron conductivity of the electrolyte material is also high. The ionic conductivity of the first solid electrolyte material at room temperature is, for example, preferably 1 × 10 ⁻⁵ S / cm or more, and more preferably 1 × 10 ⁻³ S / cm or more.

  Examples of the shape of the first solid electrolyte material include a particle shape, and among them, a true spherical shape or an elliptical spherical shape is preferable. Moreover, when the first solid electrolyte material has a particle shape, the average particle diameter is preferably in the range of 0.1 μm to 50 μm, for example. The content of the first solid electrolyte material in the electrode active material layer is preferably, for example, in the range of 0.1 wt% to 50 wt%, and in the range of 0.5 wt% to 10 wt%. More preferred.

(Iii) Second Solid Electrolyte Material The second solid electrolyte material in the present embodiment is an ionic conductor having a cation component and an anion component and not having electronic conductivity. The anion component of the second solid electrolyte material is the same as the anion portion of the first solid electrolyte material. The definitions of the cation part and the anion part in the second solid electrolyte material are the same as described above. For example, in Li ₇ P ₃ S ₁₁ , Li and P are cation components, and S is an anion component. In addition, the second solid electrolyte material usually does not have electronic conductivity, but “does not have electronic conductivity” means that the second solid electrolyte material has an insulating property that can be used for the solid electrolyte layer. The electronic conductivity of the second solid electrolyte material at room temperature is, for example, 1 × 10 ⁻¹² S / cm or less, and preferably less than the measurement limit.

  The anion component of the second solid electrolyte material in this embodiment is preferably mainly composed of chalcogen. Examples of the chalcogen include oxygen, sulfur, selenium, etc. Among them, oxygen and sulfur are preferable, and sulfur is particularly preferable. That is, it is preferable that the anion component of the second solid electrolyte material in this embodiment is mainly composed of sulfur.

  Examples of the second solid electrolyte material having an anion component mainly composed of sulfur include a sulfide solid electrolyte material. The type of the sulfide solid electrolyte material can be appropriately selected according to the type of the all-solid battery. For example, when the all-solid battery is an all-solid lithium battery, the sulfide solid electrolyte material (Li ion conductor) includes Li element and Group 13 to Group 15 elements (preferably Group 14 and Group 15). Element) and S element. Examples of the Group 13 to Group 15 element include P, Si, Ge, As, Sb, and Al. Among them, P, Si, and Ge are preferable, and P is particularly preferable.

The sulfide solid electrolyte material is preferably formed using a raw material composition containing Li ₂ S and a sulfide of an element belonging to Group 13 to Group 15. Examples of Group 13 to Group 15 element sulfides include P ₂ S ₃ , P ₂ S ₅ , SiS ₂ , GeS ₂ , As ₂ S ₃ , Sb ₂ S ₃ , and Al ₂ S _3. be able to.

  Moreover, an amorphous sulfide solid electrolyte material can be obtained by subjecting the raw material composition to an amorphization treatment. Examples of the amorphization treatment include a mechanical milling method and a melt quenching method, and among them, the mechanical milling method is preferable. This is because processing at room temperature is possible, and the manufacturing process can be simplified. Mechanical milling is not particularly limited as long as the raw material composition is mixed while applying mechanical energy. And a planetary ball mill is particularly preferable. This is because a desired sulfide solid electrolyte material can be obtained efficiently.

  Various conditions of mechanical milling are set so that a desired sulfide solid electrolyte material can be obtained. For example, when a sulfide solid electrolyte material is produced by a planetary ball mill, the raw material composition and grinding balls are added to the pot, and the treatment is performed at a predetermined rotational speed and time. In general, the higher the number of rotations, the faster the production rate of the sulfide solid electrolyte material, and the longer the treatment time, the higher the conversion rate from the raw material composition to the sulfide solid electrolyte material. The number of rotations when performing the planetary ball mill is, for example, preferably in the range of 200 rpm to 500 rpm, and more preferably in the range of 250 rpm to 400 rpm. Further, the treatment time when performing the planetary ball mill is preferably in the range of 1 hour to 100 hours, and more preferably in the range of 1 hour to 50 hours.

Moreover, a crystalline sulfide solid electrolyte material can be obtained by heat-treating the amorphous sulfide solid electrolyte material. The Li ₇ P ₃ S ₁₁ described above, for example, amorphizes a raw material composition containing Li ₂ S and P ₂ S ₅ at a molar ratio of Li ₂ S: P ₂ S ₅ = 70: 30, Furthermore, it can synthesize | combine by adding heat processing. The temperature of the heat treatment is, for example, preferably 270 ° C. or higher, more preferably 280 ° C. or higher, and further preferably 285 ° C. or higher. On the other hand, the temperature of the heat treatment is preferably, for example, 310 ° C. or less, more preferably 300 ° C. or less, and further preferably 295 ° C. or less. The heat treatment time is, for example, in the range of 1 minute to 2 hours, and more preferably in the range of 30 minutes to 1 hour.

In addition, the second solid electrolyte material in the present embodiment may have an anion component mainly composed of oxygen. Examples of such a second solid electrolyte material include an oxide solid electrolyte material. For example, in the system using the sulfide active material described above, it is effective to use an oxide solid electrolyte material as the second solid electrolyte material. Examples of the oxide solid electrolyte material (ion conductor) include La _0.5 Li _0.5 TiO ₃ , Li _1.3 Al _0.3 Ti _1.7 (PO ₄ ) ₃ , and Li ₇ La ₃ Zr _2. O ₁₂ etc. can be mentioned.

  The second solid electrolyte material may be crystalline or amorphous. The difference between crystalline and amorphous can be judged by X-ray diffraction (XRD). When the second solid electrolyte material is crystalline, there is an advantage that the ion conductivity tends to be higher than that of the amorphous solid electrolyte material. Conversely, when the second solid electrolyte material is amorphous, it is softer than the crystalline solid electrolyte material, so that the active material can be expanded and contracted, and the cycle characteristics can be improved. Have advantages.

Moreover, it is preferable that the ion conductivity of the second solid electrolyte material is high. The ionic conductivity of the second solid electrolyte material at room temperature is, for example, preferably 10 ⁻⁵ S / cm or more, and more preferably 10 ⁻⁴ S / cm or more.

  Examples of the shape of the second solid electrolyte material include a particle shape, and among them, a true spherical shape or an elliptical spherical shape is preferable. Moreover, when the second solid electrolyte material has a particle shape, the average particle diameter is preferably in the range of 0.1 μm to 50 μm, for example. The content of the second solid electrolyte material in the electrode active material layer is, for example, preferably in the range of 5 wt% to 50 wt%, and more preferably in the range of 10 wt% to 40 wt%. Furthermore, in the electrode active material layer, the ratio of the first solid electrolyte material to the total of the first solid electrolyte material and the second solid electrolyte material is preferably in the range of, for example, 1% by weight to 40% by weight. More preferably, it is in the range of% to 20% by weight.

(Iv) Electrode active material layer The electrode active material layer in this embodiment contains an active material, a first solid electrolyte material, and a second solid electrolyte material. Usually, the first solid electrolyte material is in contact with the active material, and the second solid electrolyte material is in contact with the first solid electrolyte material. In this embodiment, as shown in FIGS. 3A and 3B, the first solid electrolyte material 5 preferably covers the active material 4 or the second solid electrolyte layer 6. This is because the contact between the active material and the second solid electrolyte material can be effectively prevented. In addition, when an active material and a 2nd solid electrolyte material contact, the interface state shown to Fig.2 (a) mentioned above will arise, and it will be thought that a high resistance layer generate | occur | produces. Therefore, it is preferable that the active material and the second solid electrolyte material do not contact each other. In particular, in this embodiment, it is preferable that the first solid electrolyte material 5 covers the active material 4 as shown in FIG. This is because the active material is usually harder than the second solid electrolyte material and easily forms a coating state.

  When the first solid electrolyte material is used as a coating material, the coverage is preferably, for example, 50% or more, and more preferably in the range of 70% to 99%. Moreover, the average thickness of the covering portion formed of the first solid electrolyte material is preferably in the range of 1 nm to 1 μm, for example, and more preferably in the range of 5 nm to 0.1 μm.

  In this embodiment, as shown in FIG. 3C, the active material 4, the first solid electrolyte material 5, and the second solid electrolyte layer 6 may be in contact with each other by simple mixing. In this case, there is a portion where the active material 4 and the second solid electrolyte material 6 are in contact with each other and the interface state shown in FIG. 2A is created, but at least the materials are arranged in the order shown in FIG. The increase in resistance can be suppressed in the part. Moreover, simple mixing also has the advantage that the manufacturing process is simplified.

  In this embodiment, the surface of the active material has the same anion component as the anion component of the active material, and is coated with a third solid electrolyte material that is a single-phase electron-ion mixed conductor, and the active material and The first solid electrolyte material is preferably in contact with the third solid electrolyte material. It is because it can suppress that an active material and a 1st solid electrolyte material react, and a high resistance layer produces | generates. For example, when the active material is an oxide active material and the first solid electrolyte material is a sulfide solid electrolyte material, the surface of the oxide active material is covered with an oxide solid electrolyte material (electron-ion mixed conductor). By covering, the reaction between the oxide active material and the sulfide solid electrolyte material can be suppressed. Depending on the coverage of the third solid electrolyte material, the active material and the first solid electrolyte material are in contact with each other via the third solid electrolyte material, and the active material exposed from the coated third solid electrolyte material It is conceivable that the first solid electrolyte material is in contact. Further, specific examples of the third solid electrolyte material are the same as the contents described in the above “(ii) First solid electrolyte material”.

  Moreover, the electrode active material layer in this embodiment may further contain at least one of a conductive material and a binder. Examples of the conductive material include acetylene black, ketjen black, activated carbon, graphite, and carbon fiber. Moreover, as a binder, a fluorine-containing resin etc. can be mentioned, for example. The thickness of the electrode active material layer is, for example, in the range of 0.1 μm to 1000 μm.

  In the present embodiment, as described above, the electrode active material layer is preferably a positive electrode active material layer. In this case, the configuration of the negative electrode active material layer is not particularly limited, and any configuration can be adopted. As a negative electrode active material used for the said negative electrode active material layer, a metal active material and a carbon active material can be mentioned, for example. Examples of the metal active material include In, Al, Si, and Sn. On the other hand, examples of the carbon active material include mesocarbon microbeads (MCMB), highly oriented graphite (HOPG), hard carbon, and soft carbon.

(2) Solid electrolyte layer The solid electrolyte layer in this embodiment is a layer formed between a positive electrode active material layer and a negative electrode active material layer. The solid electrolyte layer is a layer containing a solid electrolyte material. Although it does not specifically limit as solid electrolyte material used for a solid electrolyte layer, For example, sulfide solid electrolyte material and oxide solid electrolyte material can be mentioned, Among these, sulfide solid electrolyte material is preferable. This is because a solid electrolyte layer excellent in ion conductivity can be obtained. Moreover, as a solid electrolyte material used for a solid electrolyte layer, the same material as the second solid electrolyte material described above can be used. In particular, in this embodiment, it is preferable that the second solid electrolyte material included in the electrode active material layer and the solid electrolyte material included in the solid electrolyte layer are the same material. This is because deterioration can be further prevented by using a material having the same chemical potential. Moreover, the solid electrolyte layer may contain the binder mentioned above.

  Although the thickness of a solid electrolyte layer is not specifically limited, For example, it is preferable to exist in the range of 0.1 micrometer-1000 micrometers, and it is more preferable to exist in the range of 0.1 micrometer-300 micrometers.

(3) Other members The all-solid-state battery of this embodiment has at least the electrode active material layer and the solid electrolyte layer described above. Furthermore, it usually has a positive electrode current collector for collecting current of the positive electrode active material layer and a negative electrode current collector for collecting current of the negative electrode active material. Examples of the material for the positive electrode current collector include SUS, aluminum, nickel, iron, titanium, and carbon. Among them, SUS is preferable. On the other hand, examples of the material for the negative electrode current collector include SUS, copper, nickel, and carbon. Of these, SUS is preferable. In addition, the thickness and shape of the positive electrode current collector and the negative electrode current collector are preferably appropriately selected according to the use of the all solid state battery. Moreover, the battery case of a general all-solid-state battery can be used for a battery case. Examples of the battery case include a SUS battery case. Moreover, the all-solid-state battery of this embodiment may have a power generating element formed inside an insulating ring.

(4) All-solid battery Examples of the all-solid battery of the present embodiment include an all-solid lithium battery, an all-solid sodium battery, an all-solid magnesium battery, and an all-solid calcium battery. And an all-solid sodium battery is preferable, and an all-solid lithium battery is particularly preferable. Moreover, the all-solid-state battery of this embodiment may be a primary battery or a secondary battery, but among these, a secondary battery is preferable. This is because it can be repeatedly charged and discharged and is useful, for example, as an in-vehicle battery. Examples of the shape of the all solid state battery of this embodiment include a coin type, a laminate type, a cylindrical type, and a square type. Among these, a square type and a laminate type are preferable, and a laminate type is particularly preferable.

  Moreover, the manufacturing method of the all-solid-state battery of this embodiment will not be specifically limited if it is a method which can obtain the all-solid-state battery mentioned above, The method similar to the manufacturing method of a general all-solid-state battery is used. Can be used. As an example of a method for producing an all-solid-state battery, a power generation element is manufactured by sequentially pressing a material constituting the positive electrode active material layer, a material constituting the solid electrolyte layer, and a material constituting the negative electrode active material layer, A method of storing the power generation element in the battery case and caulking the battery case can be exemplified.

2. Second Embodiment Next, a second embodiment of the all solid state battery of the present invention will be described. A second embodiment of the all solid state battery of the present invention is an all solid having a positive electrode active material layer, a negative electrode active material layer, and a solid electrolyte layer formed between the positive electrode active material layer and the negative electrode active material layer. In the battery, at least one of the positive electrode active material layer and the negative electrode active material layer has an anion component that is in contact with the active material and is different from the anion component of the active material, and has a single phase. A first solid electrolyte material that is an electron-ion mixed conductor, the solid electrolyte layer is in contact with the first solid electrolyte material, has the same anion component as the first solid electrolyte material, It contains the 2nd solid electrolyte material which is an ionic conductor which does not have property.

  FIG. 4 is an explanatory diagram showing an example of the power generation element of the all solid state battery of the second embodiment. The power generation element 10 of the all-solid battery shown in FIG. 4 includes a positive electrode active material layer 1, a negative electrode active material layer 2, a solid electrolyte layer 3 formed between the positive electrode active material layer 1 and the negative electrode active material layer 2, Have Further, the positive electrode active material layer 1 includes an active material 4 and a first solid electrolyte material 5 that contacts the active material 4, and the solid electrolyte layer 3 includes a second solid electrolyte that contacts the first solid electrolyte material 5. It has material 6.

  Thus, according to this embodiment, the anion component of the active material is different from the anion portion of the first solid electrolyte material and the second solid electrolyte material, and the first solid electrolyte material and the second solid electrolyte material By using the same anion part and using an electron-ion mixed conductor for the first solid electrolyte material, an increase in resistance at the interface between the active material and the solid electrolyte material can be effectively suppressed. In particular, when the Li ion conductivity of the first solid electrolyte material is equal to or higher than the Li ion conductivity of the second solid electrolyte material, a high-power all-solid battery can be obtained with a simple manufacturing method. .

  In this embodiment, at least one of the positive electrode active material layer and the negative electrode active material layer contains the first solid electrolyte material, and both the positive electrode active material layer and the negative electrode active material layer contain the first solid electrolyte material. May be. Especially, in this embodiment, it is preferable that a positive electrode active material layer contains a 1st solid electrolyte material. This is because there are many types of oxide active materials and the like useful as the positive electrode active material, and the effects of this embodiment are easily exhibited.

  In addition, when the positive electrode active material layer and the negative electrode active material layer are collectively referred to as an electrode active material layer, in this embodiment, at least one of the two electrode active material layers includes an active material and a first solid electrolyte material. contains. In this embodiment, it is sufficient that the active material and the first solid electrolyte material are in contact with each other. Similarly to the above “1. First embodiment”, the active material is coated with the first solid electrolyte material, so The active material and the first solid electrolyte material may be in contact by simple mixing.

  Moreover, in this embodiment, it is preferable that the 1st solid electrolyte material contained in an electrode active material layer forms the layered structure in the contact surface with a solid electrolyte layer. This is because the contact between the active material and the second solid electrolyte material can be effectively prevented. Thereby, deterioration by both contacting can be prevented. Specifically, as shown in FIG. 5, the first solid electrolyte material 5 included in the positive electrode active material layer 1 may have a layered structure at the contact surface with the solid electrolyte layer 3. it can. In addition, although the layered first solid electrolyte material 5 can be regarded as the first solid electrolyte layer 5a and can be regarded as a part of the solid electrolyte layer 3, in this embodiment, as shown in FIG. The electrolyte layer 5 a is regarded as a part constituting the positive electrode active material layer 1. Therefore, the first solid electrolyte material 5 may or may not be contained in the region of the positive electrode active material layer 1 excluding the first solid electrolyte material 5 having a layered structure. The former is preferable from the viewpoint of improving ion conductivity, and the latter is preferable from the viewpoint of increasing capacity. Moreover, the thickness of the first solid electrolyte layer 5a is preferably in the range of 0.5 μm to 100 μm, for example, and more preferably in the range of 1 μm to 10 μm.

  In the present embodiment, the solid electrolyte layer contains the second solid electrolyte material. At least a part of the second solid electrolyte material contained in the solid electrolyte layer needs to contact the first solid electrolyte material contained in the positive electrode active material layer. In this embodiment, the solid electrolyte layer may further contain a solid electrolyte material different from the second solid electrolyte material, or may contain only the second solid electrolyte material. The content of the second solid electrolyte material in the solid electrolyte layer is, for example, preferably 50% by weight or more, more preferably 70% by weight or more, and further preferably 80% by weight or more. Although the thickness of a solid electrolyte layer is not specifically limited, For example, it is preferable to exist in the range of 0.1 micrometer-1000 micrometers, and it is more preferable to exist in the range of 0.1 micrometer-300 micrometers.

  Since the active material, the first solid electrolyte material, the second solid electrolyte material, and other matters in the present embodiment are the same as the contents described in “1. First embodiment” above, the description here Omitted.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described in more detail with reference to examples.

[Synthesis example]
As starting materials, lithium sulfide (Li ₂ S) and zirconium sulfide (ZrS ₂ ) were used. These powders were mixed with Li ₂ S (0.46 g) and ZrS ₂ (1.54 g) in a glove box under an argon atmosphere, and heat-treated at 650 ° C. for 10 hours in a vacuum, whereby electron-ion A mixed conductor Li ₂ ZrS ₃ powder was obtained.

XRD measurement was performed using the obtained Li ₂ ZrS ₃ powder. The result is shown in FIG. As shown in FIG. 6, no ZrS ₂ peak was observed. Although the peak of ZrO ₂ as an impurity is confirmed, ZrO ₂ is excellent in chemical stability, since the electronic conductivity and Li have no ionic conductivity, impact can be determined that is small. Further, although a minute peak of Li ₂ S (around 2θ = 27 °) was confirmed, it can be determined that Li ₂ S does not have electron conductivity and Li ion conductivity, and therefore the influence is small. From the above, the obtained Li ₂ ZrS ₃ powder was considered to be a single-phase crystal.

Next, the electronic conductivity of the obtained Li ₂ ZrS ₃ was evaluated. The Li ₂ ZrS ₃ powder was placed in a cell made of SKD steel and pressed at 4 t to produce a pellet. When the electron conductivity was measured from the direct current resistance, the value was 2.5 × 10 ⁻³ S / cm.

Next, the Li ion conductivity of the obtained Li ₂ ZrS ₃ was evaluated. First, Li ₇ P ₃ S ₁₁ crystal, which is a sulfide solid electrolyte material, was synthesized by a method similar to the method described in JP-A-2005-228570. Next, as shown in FIG. 7, pellets were prepared in which Li ₇ P ₃ S ₁₁ layers were arranged on both sides of the Li ₂ ZrS ₃ layer, and metal Li and SKD steel were further arranged on both sides of the pellets. In this state, a potential was applied, and the Li ion conductivity of Li ₂ ZrS ₃ was measured from the DC resistance. _{Incidentally,} Li ion conductivity of Li ₇ P _{3 S 11} is known, _and, since the electronic conductivity of _Li 2 ZrS ₃ is blocked by Li ₇ P _{3 S 11,} can measure Li ion conductivity. As a result, the Li ion conductivity of Li ₂ ZrS ₃ was 9.6 × 10 ⁻¹⁰ S / cm.

[Example 1]
LiCoO ₂ was used as the positive electrode active material, and the surface of LiCoO ₂ was coated with Li ₃ V _0.8 P _0.2 O ₄ (third solid electrolyte material) that is an electron-ion mixed conductor. First, Li ₃ VO ₄ and Li ₃ PO ₄ were prepared by a sol-gel method. Next, Li ₃ VO ₄ and Li ₃ PO ₄ were mixed and pressed at a molar ratio of Li ₃ VO ₄ : Li ₃ PO ₄ = 8: 2 to form pellets (Li ₃ V _0.8 P _0.2 O ₄₎ was obtained. Using this pellet as a target, the surface of LiCoO ₂ was coated with Li ₃ V _0.8 P _0.2 O ₄ by PLD (Pulsed laser deposition) to obtain a first coated LiCoO ₂ . In addition, the electronic conductivity of Li ₃ V _0.8 P _0.2 O ₄ was 1.1 × 10 ⁻⁶ (Ω ⁻¹ · m ⁻¹ ).

Next, Li ₂ ZrS ₃ synthesized in the synthesis example is prepared as the first solid electrolyte material, and the first coated LiCoO ₂ and Li ₂ ZrS ₃ are first coated LiCoO ₂ : Li ₂ in a glove box under an argon atmosphere. The surface of the first coated LiCoO ₂ was coated with Li ₂ ZrS ₃ by weighing at a weight ratio of ZrS ₃ = 95: 5 and mixing in a mortar to obtain a second coated LiCoO ₂ . Next, the obtained second coated LiCoO ₂ and Li ₇ P ₃ S ₁₁ (second solid electrolyte material) used in the evaluation of the synthesis example were second coated LiCoO ₂ : Li ₇ P ₃ S ₁₁ = 70. : The positive electrode mixture was obtained by mixing at a weight ratio of 30.

Next, the electric power generation element 10 as shown in FIG. 1 mentioned above was produced using the press machine. The above positive electrode mixture is used as the material constituting the positive electrode active material layer 1, In foil is used as the material constituting the negative electrode active material layer 2, and Li ₇ P ₃ S ₁₁ is used as the material constituting the solid electrolyte layer 3. It was. A battery for evaluation was obtained using this power generation element.

[Comparative Example 1]
An evaluation battery was obtained in the same manner as in Example 1 except that the coating with Li ₃ V _0.8 P _0.2 O ₄ and the coating with Li ₂ ZrS ₃ were not performed. Note that LiCoO ₂ : Li ₇ P ₃ S ₁₁ = 70: 30 (weight ratio).

[Comparative Example 2]
In Comparative Example 2, a sulfide solid electrolyte material that is not a single phase was used as the first solid electrolyte material. First, a Li ₂ S—P ₂ S ₅ —FeS based non-single-phase sulfide solid electrolyte material was synthesized. Li ₂ S, P ₂ S ₅ and FeS powders were mixed in a glove box under an argon atmosphere at a molar ratio of Li ₂ S: P ₂ S ₅ : FeS = 49: 21: 30 to obtain a raw material composition. It was. Next, 1 g of the obtained raw material composition was put into a 45 ml zirconia pot, and zirconia balls (Φ10 mm, 10 pieces) were put into it, and the pot was completely sealed. Attach the pot planetary ball mill, subjected to 40 hours mechanical milling at a rotation speed of 370 rpm, to obtain a sulfide solid electrolyte material _{(49Li 2 S-21P 2 S} 5 -30FeS glass). From the results of Reference Examples described later, it is considered that this sulfide solid electrolyte material is not a single-phase compound.

An evaluation battery was obtained in the same manner as in Example 1 except that the obtained sulfide solid electrolyte material was used instead of Li ₂ ZrS ₃ .

[Comparative Example 3]
An evaluation battery was obtained in the same manner as in Example 1 except that the coating with Li ₂ ZrS ₃ was not performed. The first coating LiCoO ₂ : Li ₇ P ₃ S ₁₁ = 70: 30 (weight ratio).

[Evaluation]
Using the evaluation batteries obtained in Example 1 and Comparative Examples 1 to 3, the interface resistance increase rate was measured. First, the evaluation battery was charged. The charging conditions were as follows: constant current charging at 0.1 C to 3.34 V, and then constant voltage charging at 3.34 V for 2 hours. After charging, the interface resistance between the positive electrode active material layer and the solid electrolyte layer was determined by impedance measurement. The impedance measurement conditions were a voltage amplitude of 10 mV, a measurement frequency of 1 MHz to 0.1 Hz, and 25 ° C. Thereafter, it was stored at 60 ° C. for 30 days, and after storage, the interface resistance was determined under the same conditions as described above. The interface resistance increase rate was calculated from the interface resistance values before and after storage. The results are shown in Table 1.

As shown in Table 1, Example 1 had a smaller interface resistance increase rate than Comparative Examples 1 to 3. This is because, in Example 1, Li ₂ ZrS ₃ has electronic conductivity, so that no potential difference occurs between LiCoO ₂ and Li ₃ V _0.8 P _0.2 O ₄ and Li ₂ ZrS _3, and This is because a potential difference occurs between Li ₂ ZrS ₃ and Li ₇ P ₃ S ₁₁ , but because the interface is between sulfide solid electrolyte materials, the chemical potential difference is relaxed, and the reaction between the two is less likely to occur. it is conceivable that.

[Reference example]
A Li ₂ S—P ₂ S ₅ —FeS-based solid was obtained in the same manner as in Comparative Example 2 except that the content of FeS was changed to 0 mol%, 5 mol%, 10 mol%, 30 mol%, 50 mol%, and 70 mol%. An electrolyte material was obtained.

  X-ray diffraction measurement was performed on the obtained sulfide solid electrolyte material. The result is shown in FIG. Moreover, the obtained solid electrolyte material was pressed and pelletized, and Li ion conductivity was measured by the alternating current impedance method. Further, the electron conductivity was measured from the current value when a DC voltage was applied. The result is shown in FIG. As shown in FIGS. 8 and 9, it was confirmed that the FeS peak intensity and the electron conductivity increase as the amount of FeS added increases. This is presumably because FeS remains in a dispersed state in the matrix without becoming amorphous. Therefore, in this sulfide solid electrolyte material, it is considered that the amorphous part is responsible for Li ion conduction and the remaining FeS is responsible for electron conduction. Therefore, it is considered that this sulfide solid electrolyte material is not a single phase. In addition, since FeS is considered to correspond to MeSx of Patent Document 1 described above, the electron-lithium ion mixed conductor in Patent Document 1 is not a single-phase compound, but an electron-ion mixed conductor (first) in the present invention. One solid electrolyte material).

DESCRIPTION OF SYMBOLS 1 ... Positive electrode active material layer 2 ... Negative electrode active material layer 3 ... Solid electrolyte layer 4 ... Active material 5 ... 1st solid electrolyte material 5a ... 1st solid electrolyte layer 6 ... 2nd solid electrolyte material

Claims (9)

Active material,
A first solid electrolyte material that is in contact with the active material, has an anionic component different from the anionic component of the active material, and is a single phase electron-ion mixed conductor;
A second solid electrolyte material that is in contact with the first solid electrolyte material, has the same anion component as the first solid electrolyte material, and is an ionic conductor having no electronic conductivity;
An all-solid-state battery comprising an electrode active material layer comprising: An all-solid battery having a positive electrode active material layer, a negative electrode active material layer, and a solid electrolyte layer formed between the positive electrode active material layer and the negative electrode active material layer,
At least one of the positive electrode active material layer and the negative electrode active material layer has an anion component that is in contact with the active material and is different from the anion component of the active material, and has a single-phase electron-ion mixed conduction A first solid electrolyte material that is a body,
The solid electrolyte layer contains a second solid electrolyte material that is in contact with the first solid electrolyte material, has the same anion component as the first solid electrolyte material, and is an ionic conductor having no electronic conductivity. All-solid battery characterized by.   The all solid state battery according to claim 1, wherein the first solid electrolyte material covers the active material.   The all-solid-state battery according to claim 2, wherein the first solid electrolyte material forms a layered structure at a contact surface with the solid electrolyte layer.   The anionic component of the active material, the anionic component of the first solid electrolyte material, and the anionic component of the second solid electrolyte material are all chalcogens. The all-solid-state battery of Claim. The active material is an oxide active material in which the anion component is oxygen,
The said 1st solid electrolyte material and said 2nd solid electrolyte material are sulfide solid electrolyte materials whose said anion component is sulfur, The claim in any one of Claim 1-5 characterized by the above-mentioned. All-solid battery.   The all-solid-state battery according to any one of claims 1 to 6, wherein the first solid electrolyte material is crystalline. The all-solid-state battery according to any one of claims 1 to 7, wherein the first solid electrolyte material is Li ₂ ZrS ₃ . The surface of the active material has the same anion component as the anion component of the active material, and is coated with a third solid electrolyte material that is a single-phase electron-ion mixed conductor,
The all-solid-state battery according to any one of claims 1 to 8, wherein the active material and the first solid electrolyte material are in contact with each other through the third solid electrolyte material. .

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