Composite and battery

Abstract

To provide a composite material that can provide an electrode layer and an electrolyte layer having good ionic conductivity.SOLUTION: A composite contains a first solid electrolyte and a second solid electrolyte, and the first solid electrolyte and the second solid electrolyte contain Li, P, and S, and have an argyrodite-type crystal structure, and the first solid electrolyte contains an anion component containing B, while the second solid electrolyte does not contain an anion component containing B.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to composite materials and batteries.

Background Art

[0002] In recent years, battery development has been actively carried out. For example, in the automotive industry, the development of batteries used in battery electric vehicles (BEVs), plug-in hybrid vehicles (PHEVs), or hybrid electric vehicles (HEVs) has been progressing. Further, as an electrolyte used in batteries, inorganic solid electrolytes are known. Inorganic solid electrolytes have, for example, the advantage that it is easier to simplify safety devices compared to electrolytic solutions (liquid electrolytes) containing flammable organic solvents.

[0003] For example, Patent Document 1 discloses a solid electrolyte material containing Li, T, X, and A, where T contains at least one element selected from the group consisting of Sb, P, As, Si, Ge, Al, B, and W, X contains one or more halogens, pseudohalogens, or N, A contains one or more of S or Se, and the above solid electrolyte material has peaks at 2θ = 14.5° ± 0.50°, 16.8° ± 0.50°, 23.9° ± 0.50°, 28.1° ± 0.50°, and 32.5° ± 0.50° in X-ray diffraction measurement by Cu-Kα(1,2) = 1.54064 Å.

[0004] Patent Document 2 discloses a compound represented by the formula: Li 7-x PS 6-x X x-z (BH4) z (where X is selected from the group consisting of Cl, Br, I, F, and CN, 0 < x ≤ 2, and 0 < z ≤ 0.50).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] In order to improve battery performance, it is preferable that the ionic conductivity in the electrode layer and the electrolyte layer is good. The present disclosure has been made in view of the above-mentioned circumstances, and a main object of the present disclosure is to provide a composite material that can provide an electrode layer and an electrolyte layer having good ionic conductivity. [Means for solving the problem]

[0007] [1] A composite material containing a first solid electrolyte and a second solid electrolyte, the first solid electrolyte and the second solid electrolyte contain Li, P, and S and have an argyrodite-type crystal structure; the first solid electrolyte contains an anion component containing B, The second solid electrolyte is a composite material that does not contain an anion component containing B.

[0008] [2] The anion component containing the above B is BH4 - The composite material according to [1].

[0009] [3] The composite according to [1] or [2], wherein the proportion of the first solid electrolyte relative to the total of the first solid electrolyte and the second solid electrolyte is 7.0 wt % or more and 75.0 wt % or less.

[0010] [4] The composite material according to any one of [1] to [3], wherein a ratio of the first solid electrolyte to the total of the first solid electrolyte and the second solid electrolyte is 15.0 wt % or more and 60.0 wt % or less.

[0011] [5] The composite material according to any one of [1] to [4], wherein the second solid electrolyte contains a halogen as an anion component.

[0012] [6] The composite material according to [5], wherein the second solid electrolyte contains at least one of Cl and Br as the halogen.

[0013] [7] The composite material according to any one of [1] to [6], wherein the composite material contains an electrode active material.

[0014] [8] The composite according to [7], wherein the electrode active material contains a negative electrode active material.

[0015] [9] The composite according to [7], wherein the electrode active material contains a positive electrode active material.

[0016]

[10] A battery having a positive electrode active material layer, a negative electrode active material layer, and an electrolyte layer disposed between the positive electrode active material layer and the negative electrode active material layer, A battery in which at least one of the positive electrode active material layer, the negative electrode active material layer, and the electrolyte layer contains the composite material according to any one of [1] to [9]. [Effects of the Invention]

[0017] The present disclosure has an effect of providing a composite material that can provide an electrode layer and an electrolyte layer having good ionic conductivity. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic cross-sectional view illustrating a battery according to the present disclosure. [Figure 2] 1 is a graph showing the results of an example and a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0019] The composite and the battery according to the present disclosure will be described in detail below. Note that the drawings shown below are schematic illustrations, and the size and shape of each part are appropriately exaggerated for ease of understanding.

[0020] A. Composite The composite material according to the present disclosure contains a first solid electrolyte and a second solid electrolyte. The first solid electrolyte and the second solid electrolyte contain Li, P, and S and have an argyrodite-type crystal structure. The first solid electrolyte contains an anion component containing B, and the second solid electrolyte does not contain an anion component containing B.

[0021] The composite material in the present disclosure contains the predetermined first and second solid electrolytes, and therefore can improve the ionic conductivity in the electrode layer and the electrolyte layer.

[0022] Solid electrolytes having an argyrodite-type crystal structure (argyrodite-type solid electrolytes) are known to have good ionic conductivity (bulk ionic conductivity). Furthermore, solid electrolytes having a crystalline structure (crystalline solid electrolytes) are generally microparticulated when used in batteries. Because crystalline solid electrolytes are relatively hard, microparticulation can lead to gaps between the solid electrolytes and between the solid electrolyte and the electrode active material, potentially increasing interfacial resistance. In contrast, an argyrodite-type solid electrolyte (first solid electrolyte) containing an anion component containing B is considered to have lower bulk ionic conductivity than other argyrodite-type solid electrolytes, but is considered to be a relatively soft solid electrolyte. Therefore, the inclusion of the first solid electrolyte in the composite can fill these gaps, thereby improving the ionic conductivity of the entire composite. Furthermore, the inclusion of the first solid electrolyte in the composite can improve the packing factor of the electrode layer, potentially contributing to higher battery capacity.

[0023] 1.First solid electrolyte The first solid electrolyte contains Li, P, and S and has an argyrodite-type crystal structure. The first solid electrolyte also contains an anion component containing B. The first solid electrolyte is a different type of electrolyte from the second solid electrolyte described below, and typically does not contain a halogen as an anion component. Since the first solid electrolyte contains S, it generally falls under the category of a sulfide solid electrolyte. The same applies to the second solid electrolyte described below.

[0024] Examples of anion components containing B include BH4 - , BO3 - , B(OH)4 - and B4O7 2- Among these, the first solid electrolyte contains BH4 as an anion component. - It is preferred that the compound contains:

[0025] The first solid electrolyte is BH4 - The term "mainly containing an anion component" refers to the proportion of BH4 in the total anion components contained in the first solid electrolyte. - The first solid electrolyte contains PS4 as an anion component. 3- It is preferable that BH4 - and PS4 3- PS4 vs. the total 3- The proportion of is, for example, 20 mol% or more, and may be 25% or more. 3- The proportion is, for example, 50 mol % or less, may be 40 mol % or less, may be 35 mol % or less, or may be 30 mol % or less.

[0026] The composition of the first solid electrolyte is, for example, xLi3PS4-(100-x)Li yIn this composition, x is, for example, 20 or more, and may be 25 or more. On the other hand, x is, for example, 50 or less, and may be 40 or less, or may be 35 or less. Furthermore, M is an anion component containing B, and y is an arbitrary number determined by the valence of the anion.

[0027] The first solid electrolyte according to the present disclosure has an argyrodite-type crystal structure (crystalline phase). The presence of the argyrodite-type crystal structure in the first solid electrolyte can be confirmed by X-ray diffraction (XRD) measurement. In XRD measurement using CuKα radiation, the first solid electrolyte preferably exhibits peaks at 2θ=17.0°±0.5°, 24.1°±0.5°, 28.3°±0.5°, 29.6°±0.5°, and 38.6°±0.5°. These peaks are typical peaks of the argyrodite-type crystal phase. The positions of these peaks may be within a range of ±0.3° or ±0.1°, respectively.

[0028] The first solid electrolyte of the present disclosure preferably contains an argyrodite-type crystal structure (crystalline phase) as a main phase. The "main phase" refers to the crystal phase that has the highest intensity peak in XRD measurement using CuKα radiation.

[0029] The first solid electrolyte is usually in the form of particles. 50 ) is not particularly limited, but may be, for example, 0.01 μm or more, 0.05 μm or more, 0.10 μm or more, 0.50 μm or more, or 1.0 μm or more. On the other hand, the average particle diameter (D 50 The average particle size (D) is, for example, 30 μm or less, may be 20 μm or less, may be 10 μm or less, or may be 5 μm or less. 50 ) refers to the cumulative 50% particle size in the volume-based particle size distribution measured by a laser diffraction particle size analyzer.

[0030] The location of the first solid electrolyte in the composite is not particularly limited, but it is preferable that at least a portion of it be disposed on the surface of the second solid electrolyte described below. The proportion of the first solid electrolyte disposed on the surface of the second solid electrolyte is, for example, 5% by volume or more, 10% by volume or more, 20% by volume or more, or 30% by volume or more, relative to the entire first solid electrolyte. On the other hand, the proportion of the first solid electrolyte disposed on the surface of the second solid electrolyte is, for example, 90% by volume or less, 80% by volume or less, 70% by volume or less, 60% by volume or less, or 50% by volume or less. The first solid electrolyte may be disposed so as to coat the second solid electrolyte. For example, a coating layer containing the first solid electrolyte can be formed on the surface of the second solid electrolyte by mechanically mixing the first solid electrolyte and the second solid electrolyte by mechanical milling or the like. It is believed that forming a coating layer can effectively suppress interfacial resistance even when the proportion of the first solid electrolyte is reduced. Furthermore, it is believed that the proportion of the second solid electrolyte having a high bulk ionic conductivity can be relatively increased, thereby improving the ionic conductivity of the composite as a whole.

[0031] The proportion (weight ratio) of the first solid electrolyte to the total of the first solid electrolyte and the second solid electrolyte is not particularly limited, but may be, for example, 3.0 wt % or more, 5.0 wt % or more, 7.0 wt % or more, 10.0 wt % or more, or 15.0 wt % or more. On the other hand, the proportion of the first solid electrolyte is, for example, 98.0 wt % or less, 75.0 wt % or less, 60.0 wt % or less, 50.0 wt % or less, or 40.0 wt % or less.

[0032] The proportion (volume ratio) of the first solid electrolyte to the total of the first solid electrolyte and the second solid electrolyte is not particularly limited, but may be, for example, 3.0 vol% or more, 5.0 vol% or more, 7.0 vol% or more, 10.0 vol% or more, or 15.0 vol% or more. On the other hand, the proportion of the first solid electrolyte is, for example, 98.0 vol% or less, 75.0 vol% or less, 60.0 vol% or less, 50.0 vol% or less, or 40.0 vol% or less.

[0033] The location, weight ratio, and volume ratio of the first solid electrolyte can be calculated, for example, by SEM-EDS (scanning electron microscope / energy dispersive X-ray spectroscopy) analysis. For example, a region where boron element is confirmed can be considered to be a region of the first solid electrolyte, and a region where boron element is not confirmed but P element and S element are confirmed can be considered to be a region of the second solid electrolyte. Another example is a method of analyzing element distribution using TOF-SIMS (time-of-flight secondary ion mass spectrometry).

[0034] 2.Second solid electrolyte The second solid electrolyte contains Li, P, and S and has an argyrodite-type crystal structure. The second solid electrolyte does not contain an anion component containing B. The details other than the anion component are the same as those described in "1. First Solid Electrolyte." The term "does not contain an anion component containing B" refers to the fact that, in a spectrum obtained by XPS (X-ray photoelectron spectroscopy) of the second solid electrolyte, for example, the above-mentioned BH4 - This means that no peaks of anion components containing B are observed.

[0035] Furthermore, the second solid electrolyte preferably contains a halogen (halogen ion) as an anion component. This is because the second solid electrolyte has good ionic conductivity. Examples of halogens include F, Cl, B, and I. The second solid electrolyte may contain one type of halogen, or may contain two or more types of halogen. Among these, the second solid electrolyte preferably contains at least one of Cl and Br. The halogen may or may not be contained as a main component of the anion component. The "main component" is the same as that described in "1. First solid electrolyte." The second solid electrolyte may contain PS4 as an anion component. 3- It is preferable that the halogen and PS4 3- PS4 vs. the total 3- The proportion is, for example, 10 mol % or more, may be 20 mol % or more, or may be 30 mol % or more. 3- The proportion is, for example, 50 mol % or less, and may be 40 mol % or less.

[0036] The composition of the second solid electrolyte that does not contain a halogen is, for example, Li7PS6. The composition of the second solid electrolyte that contains a halogen is, for example, Li 7-α PS 6-α X α X is at least one halogen, and α satisfies 0<α<2. α may be 0.1 or more, 0.5 or more, or 0.7 or more. On the other hand, α may be 1.8 or less, 1.5 or less, 1.2 or less, or 1.0 or less.

[0037] 3. Mixture The composite material in the present disclosure may or may not contain an electrode active material. That is, the composite material in the present disclosure may be a composite material used in an electrode layer (a positive electrode active material layer and a negative electrode active material layer) or a composite material used in an electrolyte layer.

[0038] The electrode active material may be a negative electrode active material or a positive electrode active material.

[0039] Examples of negative electrode active materials include Si-based active materials, carbon-based active materials, and Li-based active materials. Si-based active materials are active materials containing Si element. Examples of Si-based active materials include simple Si, Si alloys, and Si oxides. The Si alloy preferably contains Si element as a main component. The proportion of Si element in the Si alloy is, for example, 50 mol% or more, or may be 70 mol% or more, or even 90 mol% or more. On the other hand, the proportion of Si element in the Si alloy is, for example, 99 mol% or less. Examples of Si alloys include Si-Al-based alloys, Si-Sn-based alloys, Si-In-based alloys, Si-Ag-based alloys, Si-Pb-based alloys, Si-Sb-based alloys, Si-Bi-based alloys, Si-Mg-based alloys, Si-Ca-based alloys, Si-Ge-based alloys, and Si-Pb-based alloys. The Si alloy may be a binary alloy or a multi-component alloy of 3 or more components. Examples of Si oxides include SiO.

[0040] The Si-based active material may have a diamond-type crystalline phase, a clathrate I-type crystalline phase, or a clathrate II-type crystalline phase. In the clathrate I-type or II-type crystalline phase, multiple Si elements form a polyhedron (cage) containing pentagons or hexagons. This polyhedron has spaces inside that can encapsulate metal ions such as Li ions, thereby suppressing volume changes due to charge and discharge.

[0041] The Si-based active material may have voids inside the primary particles. The voids can suppress volumetric changes in the active material and can suppress cracking of the electrode layer (negative electrode active material layer). The void ratio is not particularly limited, but is, for example, 4% or more and 40% or less. The presence of voids in the primary particles and the void ratio can be confirmed by observation with a SEM (scanning electron microscope).

[0042] Carbon-based active materials are inorganic active materials containing C element, such as graphite, hard carbon, and soft carbon, while Li-based active materials are active materials containing Li element, such as simple Li and Li alloys.

[0043] Examples of the positive electrode active material include oxide active materials, such as LiCoO2, LiMnO2, LiNiO2, LiVO2, and LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 Rock salt layered active materials such as O2, LiMn2O4, Li4Ti5O 12 , Li(Ni 0.5 Mn 1.5 )O4, and olivine type active materials such as LiFePO4, LiMnPO4, LiNiPO4, and LiCoPO4.

[0044] A coating layer containing a Li-ion conductive oxide may be formed on the surface of the oxide active material. This is because it can suppress the reaction between the oxide active material and the solid electrolyte (especially a sulfide solid electrolyte). An example of the Li-ion conductive oxide is LiNbO3. The thickness of the coating layer is, for example, 1 nm or more and 30 nm or less. Furthermore, Li2S, for example, can also be used as the positive electrode active material.

[0045] The electrode active material may be in the form of particles, for example. 50 ) is, for example, 10 nm or more and 50 μm or less. 50 ) are as described above. When the composite material contains an electrode active material, the proportion of the electrode active material in the composite material is, for example, 50% by weight or more and 90% by weight or less.

[0046] Furthermore, the composite material in the present disclosure may contain at least one of a conductive aid and a binder, if necessary.

[0047] Examples of the conductive additive include carbon materials, metal particles, and conductive polymers. Examples of the carbon material include particulate carbon materials such as acetylene black (AB) and ketjen black (KB), and fibrous carbon materials such as carbon fiber, carbon nanotubes (CNT), and carbon nanofibers (CNF). The proportion of the conductive additive in the composite is, for example, 0.01% by weight or more and 10% by weight or less.

[0048] Examples of binders include rubber-based binders such as butadiene rubber (BR), acrylate butadiene rubber (ABR), and styrene butadiene rubber (SBR), as well as fluorine-containing binders such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE). The proportion of the binder in the composite is, for example, 0.01% by weight or more and 5% by weight or less.

[0049] B.Battery Fig. 1 is a schematic cross-sectional view illustrating a battery according to the present disclosure. The battery 10 shown in Fig. 1 has a positive electrode active material layer 1, a negative electrode active material layer 2, and an electrolyte layer 3 disposed between the positive electrode active material layer 1 and the negative electrode active material layer 2. The battery 10 also has a positive electrode current collector 4 that collects electrons from the positive electrode active material layer 1, and a negative electrode current collector 5 that collects electrons from the negative electrode active material layer 2. In particular, in the battery 10 according to the present disclosure, at least one of the positive electrode active material layer 1, the negative electrode active material layer 2, and the electrolyte layer 3 contains the composite material described above.

[0050] 1. Positive electrode active material layer and negative electrode active material layer The positive electrode active material layer is a layer containing at least a positive electrode active material, and preferably contains the above-mentioned composite. The composite is the same as that described in "A. Composite." The thickness of the positive electrode active material layer is not particularly limited, but is, for example, 0.1 μm or more and 1000 μm or less.

[0051] The negative electrode active material layer is a layer containing at least a negative electrode active material, and preferably contains the above-mentioned composite. The composite is the same as that described in "A. Composite." The thickness of the negative electrode active material layer is not particularly limited, but is, for example, 0.1 μm or more and 1000 μm or less.

[0052] 2. Electrolyte layer The electrolyte layer is a layer disposed between the positive electrode active material layer and the negative electrode active material layer, and contains at least an electrolyte. The electrolyte layer preferably contains the composite material described above. The composite material is the same as that described in "A. Composite Material."

[0053] Generally, an electrolyte layer containing a solid electrolyte is called a solid electrolyte layer, and a battery having a solid electrolyte layer is called a solid-state battery. The solid-state battery may be a semi-solid-state battery or an all-solid-state battery. When the solid electrolyte layer in a solid-state battery contains only an inorganic solid electrolyte as the electrolyte, the solid-state battery is called an all-solid-state battery.

[0054] Examples of the solid electrolyte include the first solid electrolyte and the second solid electrolyte described above. Examples of the solid electrolyte also include inorganic solid electrolytes such as sulfide solid electrolytes, oxide solid electrolytes, nitride solid electrolytes, halide solid electrolytes, and complex hydrides, other than the first solid electrolyte and the second solid electrolyte. Oxide solid electrolytes, nitride solid electrolytes, and halide solid electrolytes typically contain oxygen (O), nitrogen (N), and halogen (X), respectively, as the main anion element components.

[0055] The solid electrolyte may also include organic solid electrolytes such as polymer electrolytes and gel electrolytes.

[0056] On the other hand, the electrolyte layer may contain an electrolytic solution as the electrolyte. Examples of the electrolytic solution include conventionally known electrolytic solutions used in batteries. Specifically, examples include electrolytic solutions containing a lithium salt such as LiPF6 and a non-aqueous solvent such as ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC). When the electrolyte solution is contained as the electrolyte, the electrolyte layer may be a layer in which the separator is impregnated with the electrolytic solution. The separator may be a conventionally known member.

[0057] The thickness of the electrolyte layer is not particularly limited, but is, for example, 0.1 μm or more and 1000 μm or less.

[0058] 3. Other configurations The battery in the present disclosure typically has a positive electrode current collector and a negative electrode current collector. Materials for the positive electrode current collector include, for example, SUS, aluminum, nickel, iron, titanium, and carbon. Materials for the negative electrode current collector include, for example, SUS, copper, nickel, and carbon.

[0059] The battery according to the present disclosure may also include an exterior body that houses the above-described components. Examples of the exterior body include a laminate-type exterior body and a case-type exterior body. The battery according to the present disclosure may also include a restraining jig that applies a restraining pressure in the thickness direction to the above-described components. A known jig can be used as the restraining jig. The restraining pressure may be, for example, 0.1 MPa or more and 50 MPa or less, or 1 MPa or more and 20 MPa or less.

[0060] 4.Battery The battery in the present disclosure may be a liquid-based battery in which the electrolyte layer contains an electrolytic solution, or a solid-state battery in which the electrolyte layer contains a solid electrolyte. As described above, the solid-state battery may be a semi-solid-state battery or an all-solid-state battery.

[0061] The type of battery in the present disclosure is not particularly limited, but is typically a lithium-ion battery. The battery in the present disclosure may be a primary battery or a secondary battery, but a secondary battery is preferred because it can be repeatedly charged and discharged and is useful, for example, as an in-vehicle battery.

[0062] The use of the battery in the present disclosure is not particularly limited, but examples include power sources for vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), electric vehicles (BEVs), gasoline-powered vehicles, and diesel-powered vehicles. In particular, it is preferable that the battery be used as a driving power source for hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), or electric vehicles (BEVs). The battery in the present disclosure may also be used as a power source for mobile objects other than vehicles (e.g., trains, ships, and aircraft), or as a power source for electrical appliances such as information processing devices.

[0063] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Example]

[0064] [Example 1] First, a first solid electrolyte (BH4 argyrodite) was prepared as follows. Li2S (11.4828 g) and P2S5 (18.5172 g) were weighed out and then ball-milled in heptane using a 500 ml ZrO2 pot (ball diameter 5 mm). This yielded Li3PS4. Li3PS4 and LiBH4 were weighed out to a molar ratio of 1:3 and then ball-milled in heptane using a 500 ml ZrO2 pot (ball diameter 5 mm). This yielded the first solid electrolyte (BH4 argyrodite). The resulting first solid electrolyte was subjected to wet particle size adjustment using a ball mill. The ball mill used balls with a diameter of 0.3 mm, and the solvent was a mixture of heptane and dibutyl ether. The mixture was then calcined in an inert atmosphere at 150°C for 3 hours.

[0065] Next, a second solid electrolyte (halogen-based argyrodite) was prepared as follows. Li2S (0.2892 g), P2S5 (0.3682 g), LiCl (0.1124 g), and LiBr (0.2302 g) were mixed and ball milled using a 45 ml ZrO2 pot (ball diameter 5 mm). The resulting mixed powder was calcined in an inert atmosphere at 500 °C for 4 hours. This resulted in a second solid electrolyte (halogen-based argyrodite). The resulting second solid electrolyte was pulverized using a mortar and further ball milled for wet particle size adjustment. Note that balls with a diameter of 1 mm were used in the ball mill, and a mixed solvent of heptane and butyl butyrate was used as the solvent.

[0066] The first solid electrolyte and the second solid electrolyte were weighed and mixed in a mortar so that the ratio of the first solid electrolyte to the total of the first solid electrolyte and the second solid electrolyte was 10.0 wt %. A composite containing the first solid electrolyte and the second solid electrolyte was thus prepared. This composite was used as a sample for the evaluation described below. Although not shown, XRD measurements of the first solid electrolyte and the second solid electrolyte confirmed that the peak of the argyrodite-type crystalline phase was the main peak.

[0067] [Examples 2 to 5] Composite materials were prepared in the same manner as in Example 1, except that the proportion of the first solid electrolyte was changed as shown in Table 1. These composite materials were used as samples to carry out the evaluations described below.

[0068] [Comparative Examples 1 and 2] The above-described first solid electrolyte or second solid electrolyte was used as a sample for evaluation as described below.

[0069] [evaluation] <Measurement of ionic conductivity> Each of the above samples was pressed using a McCorm cylinder at a pressure of 6 tons to prepare a green compact. The green compact was subjected to impedance measurement at 25°C to determine the resistance, and the ionic conductivity was calculated from the shape factor. The results are shown in Table 1 and Figure 2.

[0070] [Table 1]

[0071] As shown in Table 1 and Figure 2, the composite material of the present disclosure exhibited good ionic conductivity, suggesting that the use of the composite material of the present disclosure in a battery would improve the ionic conductivity in the electrode layer and electrolyte layer. [Explanation of symbols]

[0072] 1...Cathode active material layer 2...Negative electrode active material layer 3...electrolyte layer 4...Positive electrode current collector 5...Negative electrode current collector 10...battery

Claims

1. A composite material containing a first solid electrolyte and a second solid electrolyte, the first solid electrolyte and the second solid electrolyte contain Li, P, and S and have an argyrodite-type crystal structure; the first solid electrolyte contains an anion component containing B, The second solid electrolyte is a composite material that does not contain an anion component containing B.

2. The anion component containing B is BH ４ － 2. The composite of claim 1, wherein:

3. 2. The composite according to claim 1, wherein a ratio of the first solid electrolyte to a total of the first solid electrolyte and the second solid electrolyte is 7.0 wt % or more and 75.0 wt % or less.

4. 2. The composite material according to claim 1, wherein a ratio of the first solid electrolyte to a total of the first solid electrolyte and the second solid electrolyte is 15.0 wt % or more and 60.0 wt % or less.

5. The composite material according to claim 1 , wherein the second solid electrolyte contains a halogen as an anion component.

6. The composite material according to claim 5 , wherein the second solid electrolyte contains at least one of Cl and Br as the halogen.

7. The composite of claim 1 , wherein the composite contains an electrode active material.

8. The composite according to claim 7 , wherein the electrode active material contains a negative electrode active material.

9. The composite according to claim 7 , wherein the electrode active material contains a positive electrode active material.

10. A battery having a positive electrode active material layer, a negative electrode active material layer, and an electrolyte layer disposed between the positive electrode active material layer and the negative electrode active material layer, A battery, wherein at least one of the positive electrode active material layer, the negative electrode active material layer, and the electrolyte layer contains the composite material according to any one of claims 1 to 9.

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