KR20210037540A - Solid ion conductor compound, solid electrolyte comprising the same, electrochemical cell comprising the same, and preparation method thereof - Google Patents

Abstract

A solid ion conductor compound represented by the following chemical formula 1 and having an argyrodite-type crystal structure, a solid electrolyte comprising the same, an electrochemical cell comprising the same, and a manufacturing method thereof are provided. In the chemical formula 1: Li_aM1_xM2_wPS_yM3_z: M1 is at least one element selected from Groups 2 and 11 of the periodic table; M2 is at least one metal element other than Li selected from Group 1 of the periodic table; M3 is at least one element selected from Group 17 of the periodic table; and 4 <= a <= 8, 0 < x < 0.5, 0 <= w < 0.5, 3 <= y <= 7, and 0 <= z <= 2. Accordingly, an electrochemical cell having improved stability and cycle characteristics is provided.

Description

Solid ion conductor compound, solid electrolyte comprising the same, and an electrochemical cell comprising the same, and a manufacturing method thereof {Solid ion conductor compound, solid electrolyte comprising the same, electrochemical cell comprising the same, and preparation method thereof}

It relates to a solid ion conductor compound, a solid electrolyte comprising the same, a lithium battery comprising the same, and a method of manufacturing the same.

The all-solid lithium battery contains a solid electrolyte as an electrolyte. All solid lithium batteries do not contain flammable organic solvents, so they have excellent stability.

Conventional solid electrolyte materials are not sufficiently stable against lithium metal. In addition, the lithium ion conductivity of the conventional solid electrolyte is lower than that of the liquid substitute.

One aspect is to provide a solid ion conductor compound having improved lithium ion conductivity and stability to lithium metal by having a new composition.

Another aspect is to provide a solid electrolyte including the solid ion conductor compound.

Another aspect is to provide an electrochemical cell including the solid ion conductor compound.

Another aspect is to provide a method of manufacturing the solid ion conductor.

According to one aspect, there is provided a solid ion conductor compound represented by the following formula (1) and having an azirodite crystal structure:

<Formula 1>

Li _a M1 _x M2 _w PS _y M3 _z

In the above formula,

M1 is one or more elements selected from groups 2 and 11 of the periodic table,

M2 is one or more metal elements other than Li selected from Group 1 of the periodic table,

M3 is one or more elements selected from group 17 of the periodic table,

4≤a≤8, 0<x<0.5, 0≤w<0.5, 3≤y≤7, and 0≤z≤2.

According to the other side

A solid electrolyte comprising the solid ion conductor compound according to the above is provided.

According to another aspect

An anode layer including a cathode active material layer;

A negative electrode layer including a negative electrode active material layer; And

It includes an electrolyte layer disposed between the anode layer and the cathode layer,

An electrochemical cell in which the positive electrode active material layer and the electrolyte layer contain the solid ion conductor compound according to the above is provided.

According to another aspect

Compounds containing lithium; A compound containing an element selected from groups 2 and 11 of the periodic table; Compounds containing phosphorus (P); And a compound containing a Group 17 element; contacting to provide a mixture; And

There is provided a method for producing a solid ion conductor compound comprising; heat-treating the mixture in an inert atmosphere to provide a solid ion conductor compound.

According to one aspect, an electrochemical cell having improved stability and cycle characteristics is provided by including a solid ion conductor compound having improved lithium ion conductivity and stability against lithium metal.

1 is a powder XRD spectrum of the solid ion conductor compounds prepared in Examples 2 to 5.
2 is a graph showing ionic conductivity measurement results for solid ion conductor compounds prepared in Examples 1 to 7 and Comparative Example 1. FIG.
3 is a graph showing the life characteristics of the all-solid secondary batteries prepared in Example 13 and Comparative Example 2.
4 is a schematic diagram of an embodiment of an all-solid secondary battery.
5 is a schematic diagram of another embodiment of an all-solid secondary battery.
6 is a schematic diagram of another embodiment of an all-solid secondary battery.
<Explanation of symbols for major parts of drawings>
1, 1a: all-solid secondary battery 10: positive electrode
11: positive electrode current collector 12: positive electrode active material layer
20: negative electrode 21: negative electrode current collector
22: negative active material layer 23: metal layer
30: solid electrolyte layer 40: all-solid secondary battery

Various embodiments are shown in the accompanying drawings. However, this creative idea may be embodied in many different forms, and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided so that the present disclosure can be made thorough and complete, and will sufficiently convey the scope of the present inventive idea to those of ordinary skill in the art. The same reference numerals refer to the same components.

When a component is referred to as being "above" another component, it will be understood that it may be directly on top of another component or that other components may be interposed therebetween. In contrast, when a component is referred to as being "directly above" of another component, there are no components intervening therebetween.

Terms such as “first”, “second”, “third” may be used herein to describe various elements, components, regions, layers and/or regions, but these elements, components, regions, The layer and/or zone should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or region from another element, component, region, layer or region. Accordingly, a first component, component, region, layer or region described below may be referred to as a second component, component, region, layer or region without departing from the teachings of this specification.

The terms used in the present specification are intended to describe only specific embodiments and are not intended to limit the inventive idea. As used herein, the singular form is intended to include the plural form including “at least one” unless the content clearly dictates otherwise. "At least one" should not be construed as limiting to the singular. As used herein, the term “and/or” includes any and all combinations of one or more of the list items. The terms "comprising" and/or "comprising" as used in the detailed description specify the presence of a specified feature, region, integer, step, action, component, and/or component, and one or more other features, regions, integers The presence or addition of, steps, actions, elements, components and/or groups thereof is not excluded.

Spatially relative terms such as "bottom", "bottom", "bottom", "top", "top", "top", etc. are used to easily describe the relationship of one component or feature to another component or feature. Can be used here. It will be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations shown in the figures. For example, if the device in the figure is turned over, a component described as “below” or “below” another component or feature will be oriented “above” the other component or feature. Thus, the exemplary term “below” may encompass both an upward and downward direction. The device may be placed in different directions (rotated 90 degrees or rotated in different directions), and spatially relative terms used herein may be interpreted accordingly.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In addition, it is also understood that terms as defined in a commonly used dictionary should be construed as having a meaning consistent with their meaning within the context of the relevant technology and the present disclosure, and should not be interpreted as an idealized or excessively formal meaning. Will be.

Exemplary implementations are described herein with reference to a cross-sectional view, which is a schematic diagram of idealized implementations. As such, deformations from the shape of the city should be expected as a result of, for example, manufacturing techniques and/or tolerances. Accordingly, the embodiments described herein should not be construed as being limited to the specific shapes of regions as shown herein, but should include variations in shapes resulting from manufacturing, for example. For example, an area shown or described as being flat may typically have rough and/or non-linear characteristics. Moreover, the sharply depicted angles may be round. Accordingly, the areas shown in the drawings are schematic in nature, and their shapes are not intended to show the exact shape of the area, and are not intended to limit the scope of the present claims.

"Family" means a group of the Periodic Table of the Elements according to the International Federation of Pure and Applied Chemistry ("IUPAC") Groups 1-18 Family Classification System.

While specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are currently unexpected or unforeseeable may occur to the applicant or skilled in the art. Accordingly, it is intended that the appended claims, as filed and amended, include all such alternatives, modifications, variations, improvements and substantial equivalents.

Hereinafter, a solid ion conductor compound according to one or more exemplary embodiments, a solid electrolyte including the same, an electrochemical cell including the same, and a method of preparing the solid ion conductor compound will be described in more detail below.

[Solid ion conductor compound]

The solid ion conductor compound according to an embodiment is represented by the following formula (1), and has an azirodite crystal structure:

<Formula 1>

Li _a M1 _x M2 _w PS _y M3 _z

In the above formula, M1 is one or more elements selected from Groups 2 and 11 of the periodic table, M2 is one or more metal elements other than Li selected from Group 1 of the periodic table, M3 is one or more elements selected from Group 17 of the periodic table, 4≤a≤ 8, 0<x<0.5, 0≦w<0.5, 3≦y≦7, and 0≦z≦2. For example, 5≤a≤8, 0<x<0.5, 0≤w<0.5, 4≤y≤7, and 0≤z≤2. For example, 5≤a≤7, 0<x<0.5, 0≤w<0.5, 4≤y≤6, and 0≤z≤2. For example, 5.5≤a≤7, 0<x<0.5, 0≤w<0.5, 4.5≤y≤6, and 0.2≤z≤1.8.

The compound represented by Formula 1 is, for example, a crystalline compound having a crystal structure, and by including M and/or Me substituted in a part of the lithium site in the crystal structure, in the compound The ionic conductivity of lithium ions can be improved and the activation energy can be reduced. For example, the crystal lattice volume (crystal lattice volume) is formed by disposing other ions having the same oxidation number as lithium and having an ionic radius that is similar or larger than that of lithium ions in a part of the lithium site contained in the solid ion conductor compound represented by Formula 1 lattice volume) can be increased. By increasing the volume of the crystal lattice, the movement of lithium ions within the crystal lattice may be facilitated. In addition, for example, a part of the lithium site contained in the solid ion conductor compound represented by Formula 1 has a larger oxidation number than that of lithium ions, that is, ions having an oxidation number of 2 or more are disposed, so that a part of the lithium site is vacant. site). The presence of an empty site in the crystal lattice may facilitate the movement of lithium ions within the crystal lattice. In Formula 1, for example, M1 may be a monovalent cation or a divalent cation.

In the solid ion conductor compound represented by Formula 1, for example, M1 may include Cu, Ag, Mg, or a combination thereof.

In the solid ion conductor compound represented by Formula 1, for example, M2 may include Na, K, or a combination thereof.

In the solid ion conductor compound represented by Formula 1, for example, M3 may include F, Cl, Br, I, or a combination thereof.

The solid ion conductor compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by Formula 2:

<Formula 2>

Li _7-xz M1 _x PS _6-z M3 _z

In the above formula, M1 is at least one element selected from Groups 2 and 11 of the periodic table, is a monovalent cation, M3 is at least one element selected from Group 17 of the periodic table, is -1 is an anion, 0<x<0.5 and 0≤z ≤2. In the above formula, for example, 0<x<0.3, 0<x<0.1, 0<x<0.05, 0<x<0.04, or 0<x<0.03.

Suitable monovalent cations selected from groups 2 and 11 of the periodic table are, for example, Cu, Ag, Mg, and the like. Suitable monovalent anions selected from group 17 of the periodic table are, for example, F, Cl, Br, I or combinations thereof. Combinations of these are, for example, a combination of Cl and Br, a combination of Cl and I, or a combination of Cl and F.

The solid ion conductor compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by Formula 2a:

<Formula 2a>

Li _7-xz M1 _x PS _6-z Cl _z

In the above formula, M1 is Cu, Ag, Mg, or a combination thereof, and 0<x<0.5 and 1≤z≤2. In the above formula, for example, 0<x<0.3, 0<x<0.1, 0<x<0.05, 0<x<0.04, or 0<x<0.03.

The solid ion conductor compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by the following Formula 2b:

<Formula 2b>

Li _5.75-x M1 _x PS _4.75 Cl _1.25

In the above formula, M1 is Cu, Ag, Mg, or a combination thereof, and 0<x<0.05. In the above formula, for example, 0<x<0.04, or 0<x<0.03.

The solid ion conductor compound represented by Formula 1 may be, for example, a solid electrolyte compound represented by Formula 3:

<Formula 3>

(Li _1-b M1 _b ) _7-z PS _6-z M3 _z

In the above formula, M1 is at least one element selected from Groups 2 and 11 of the periodic table, is a monovalent cation, M3 is at least one element selected from Group 17 of the periodic table, is -1 anion, 0<b≤0.06 and 0≤z ≤2. In the above formula, for example, 0<b≤0.05, 0<b≤0.04, 0<b≤0.03, 0<b≤0.02, 0<b≤0.01, 0<b≤0.005, or 0<b≤0.002. .

The solid ion conductor compound represented by Formula 1 may be, for example, a solid electrolyte compound represented by Formulas 3a to 3c:

<Formula 3a>

(Li _1-b Cu _b ) _7-z PS _6-z M3 _z

<Formula 3b>

(Li _1-b Ag _b ) _7-z PS _6-z M3 _z

<Formula 3c>

(Li _1-b Mg _b ) _7-z PS _6-z M3 _z

In the above formulas, M3 is F, Cl, Br, I or a combination thereof, and 0<b≤0.06 and 0≤z≤2. In the above equations, for example, 0<b<0.05. In the above equations, for example, 0<b≤0.04, 0<b≤0.03, 0<b≤0.02, 0<b≤0.01, 0<b≤0.005, or 0<b≤0.002.

The solid ion conductor compound represented by Formula 1 may be represented by, for example, the following formulas:

(Li _1-b Cu _b ) _7-z PS _6-z Cl _z , (Li _1-b Ag _b ) _7-z PS _6-z Cl _z , (Li _1-b Mg _b ) _7-z PS _{6- z} Cl _z , (Li _1-b Cu _b ) _7-z PS _6-z Br _z , (Li _1-b Ag _b ) _7-z PS _6-z Br _z , (Li _1-b Mg _b ) _{7- z} PS _6-z Br _z , (Li _1-b Cu _b ) _7-z PS _6-z I _z , (Li _1-b Ag _b ) _7-z PS _6-z I _z , (Li _1-b Mg _b ) _7-z PS _6-z I _z

In the above equations, 0<b≤0.05 and 0<z≤2. In the above equations, for example, 0<b≤0.04, 0<b≤0.03, 0<b≤0.02, 0<b≤0.01, 0<b≤0.005, or 0<b≤0.002.

The solid ion conductor compound represented by Formula 1 may be, for example, specific solid electrolyte compounds represented by the following formulas.

(Li _5.74 Cu _0.01 ) PS _4.75 Cl _1.25 , (Li _5.73 Cu _0.02 ) PS _4.75 Cl _1.25 , (Li _5.72 Cu _0.03 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.04 ) PS _4.75 Cl _1.25 , (Li _5.70 Cu _0.05 ) PS _4.75 Cl _1.25 , (Li _5.69 Cu _0.06 ) PS _4.75 Cl _1.25 , (Li _5.66 Cu _0.09 ) PS _4.75 Cl _1.25 , (Li _5.63 Cu _0.12 ) PS _4.75 Cl _1.25 , (Li _5.60 Cu _0.15 ) PS _4.75 Cl _1.25 , ( Li _5.57 Cu _0.18 ) PS _4.75 Cl _1.25 , (Li _5.54 Cu _0.21 ) PS _4.75 Cl _1.25 , (Li _5.45 Cu _0.30 ) PS _4.75 Cl _1.25 ,

(Li _5.74 Ag _0.01 ) PS _4.75 Cl _1.25 , (Li _5.73 Ag _0.02 ) PS _4.75 Cl _1.25 , (Li _5.72 Ag _0.03 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.04 ) PS _4.75 Cl _1.25 , (Li _5.70 Ag _0.05 ) PS _4.75 Cl _1.25 , (Li _5.69 Ag _0.06 ) PS _4.75 Cl _1.25 , (Li _5.66 Ag _0.09 ) PS _4.75 Cl _1.25 , (Li _5.63 Ag _0.12 ) PS _4.75 Cl _1.25 , (Li _5.60 Ag _0.15 ) PS _4.75 Cl _1.25 , ( Li _5.57 Ag _0.18 ) PS _4.75 Cl _1.25 , (Li _5.54 Ag _0.21 ) PS _4.75 Cl _1.25 , (Li _5.45 Ag _0.30 ) PS _4.75 Cl _1.25 ,

(Li _5.74 Mg _0.01 ) PS _4.75 Cl _1.25 , (Li _5.73 Mg _0.02 ) PS _4.75 Cl _1.25 , (Li _5.72 Mg _0.03 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.04 ) PS _4.75 Cl _1.25 , (Li _5.70 Mg _0.05 ) PS _4.75 Cl _1.25 , (Li _5.69 Mg _0.06 ) PS _4.75 Cl _1.25 , (Li _5.66 Mg _0.09 ) PS _4.75 Cl _1.25 , (Li _5.63 Mg _0.12 ) PS _4.75 Cl _1.25 , (Li _5.60 Mg _0.15 ) PS _4.75 Cl _1.25 , ( Li _5.57 Mg _0.18 ) PS _4.75 Cl _1.25 , (Li _5.54 Mg _0.21 ) PS _4.75 Cl _1.25 , (Li _5.45 Mg _0.30 ) PS _4.75 Cl _1.25 ,

(Li _5.74 Cu _0.01 ) PS _4.75 Br _1.25 , (Li _5.73 Cu _0.02 ) PS _4.75 Br _1.25 , (Li _5.72 Cu _0.03 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.04 ) PS _4.75 Br _1.25 , (Li _5.70 Cu _0.05 ) PS _4.75 Br _1.25 , (Li _5.69 Cu _0.06 ) PS _4.75 Br _1.25 , (Li _5.66 Cu _0.09 ) PS _4.75 Br _1.25 , (Li _5.63 Cu _0.12 ) PS _4.75 Br _1.25 , (Li _5.60 Cu _0.15 ) PS _4.75 Br _1.25 , ( Li _5.57 Cu _0.18 ) PS _4.75 Br _1.25 , (Li _5.54 Cu _0.21 ) PS _4.75 Br _1.25 , (Li _5.45 Cu _0.30 ) PS _4.75 Br _1.25 ,

(Li _5.74 Ag _0.01 ) PS _4.75 Br _1.25 , (Li _5.73 Ag _0.02 ) PS _4.75 Br _1.25 , (Li _5.72 Ag _0.03 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.04 ) PS _4.75 Br _1.25 , (Li _5.70 Ag _0.05 ) PS _4.75 Br _1.25 , (Li _5.69 Ag _0.06 ) PS _4.75 Br _1.25 , (Li _5.66 Ag _0.09 ) PS _4.75 Br _1.25 , (Li _5.63 Ag _0.12 ) PS _4.75 Br _1.25 , (Li _5.60 Ag _0.15 ) PS _4.75 Br _1.25 , ( Li _5.57 Ag _0.18 ) PS _4.75 Br _1.25 , (Li _5.54 Ag _0.21 ) PS _4.75 Br _1.25 , (Li _5.45 Ag _0.30 ) PS _4.75 Br _1.25 ,

(Li _5.74 Mg _0.01 ) PS _4.75 Br _1.25 , (Li _5.73 Mg _0.02 ) PS _4.75 Br _1.25 , (Li _5.72 Mg _0.03 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.04 ) PS _4.75 Br _1.25 , (Li _5.70 Mg _0.05 ) PS _4.75 Br _1.25 , (Li _5.69 Mg _0.06 ) PS _4.75 Br _1.25 , (Li _5.66 Mg _0.09 ) PS _4.75 Br _1.25 , (Li _5.63 Mg _0.12 ) PS _4.75 Br _1.25 , (Li _5.60 Mg _0.15 ) PS _4.75 Br _1.25 , ( Li _5.57 Mg _0.18 ) PS _4.75 Br _1.25 , (Li _5.54 Mg _0.21 ) PS _4.75 Br _1.25 , (Li _5.45 Mg _0.30 ) PS _4.75 Br _1.25 ,

(Li _5.74 Cu _0.01 ) PS _4.75 I _1.25 , (Li _5.73 Cu _0.02 ) PS _4.75 I _1.25 , (Li _5.72 Cu _0.03 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.04 ) PS _4.75 I _1.25 , (Li _5.70 Cu _0.05 ) PS _4.75 I _1.25 , (Li _5.69 Cu _0.06 ) PS _4.75 I _1.25 , (Li _5.66 Cu _0.09 ) PS _4.75 I _1.25 , (Li _5.63 Cu _0.12 ) PS _4.75 I _1.25 , (Li _5.60 Cu _0.15 ) PS _4.75 I _1.25 , ( Li _5.57 Cu _0.18 ) PS _4.75 I _1.25 , (Li _5.54 Cu _0.21 ) PS _4.75 I _1.25 , (Li _5.45 Cu _0.30 ) PS _4.75 I _1.25 ,

(Li _5.74 Ag _0.01 ) PS _4.75 I _1.25 , (Li _5.73 Ag _0.02 ) PS _4.75 I _1.25 , (Li _5.72 Ag _0.03 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.04 ) PS _4.75 I _1.25 , (Li _5.70 Ag _0.05 ) PS _4.75 I _1.25 , (Li _5.69 Ag _0.06 ) PS _4.75 I _1.25 , (Li _5.66 Ag _0.09 ) PS _4.75 I _1.25 , (Li _5.63 Ag _0.12 ) PS _4.75 I _1.25 , (Li _5.60 Ag _0.15 ) PS _4.75 I _1.25 , ( Li _5.57 Ag _0.18 ) PS _4.75 I _1.25 , (Li _5.54 Ag _0.21 ) PS _4.75 I _1.25 , (Li _5.45 Ag _0.30 ) PS _4.75 I _1.25 ,

(Li _5.74 Mg _0.01 ) PS _4.75 I _1.25 , (Li _5.73 Mg _0.02 ) PS _4.75 I _1.25 , (Li _5.72 Mg _0.03 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.04 ) PS _4.75 I _1.25 , (Li _5.70 Mg _0.05 ) PS _4.75 I _1.25 , (Li _5.69 Mg _0.06 ) PS _4.75 I _1.25 , (Li _5.66 Mg _0.09 ) PS _4.75 I _1.25 , (Li _5.63 Mg _0.12 ) PS _4.75 I _1.25 , (Li _5.60 Mg _0.15 ) PS _4.75 I _1.25 , ( Li _5.57 Mg _0.18 ) PS _4.75 I _1.25 , (Li _5.54 Mg _0.21 ) PS _4.75 I _1.25 , (Li _5.45 Mg _0.30 ) PS _4.75 I _1.25 ,

The solid ion conductor compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by Formula 4:

<Formula 4>

Li _7-xwz M1 _x M2 _w PS _6-z M3 _z

In the above formula, M1 is one or more elements selected from Groups 2 and 11 of the periodic table, and is a monovalent cation, M2 is one or more metal elements other than Li selected from Group 1 of the periodic table, and is a monovalent cation, and M3 is from Group 17 of the periodic table. Is one or more selected elements, -1 is an anion, 0<x<0.5, 0≦w<0.5, 0<x+w<0.5, and 0≦z≦2. In the above formula, for example, 0<x+w<0.3, 0<x+w<0.1, 0<x+w<0.05, 0<x+w<0.04, or 0<x+w<0.03.

Suitable monovalent cations selected from groups 2 and 11 of the periodic table are, for example, Cu, Ag, Mg, and the like.

Suitable monovalent cations selected from group 1 of the periodic table are, for example, Na, K, and the like.

The solid ion conductor compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by Formula 4a:

<Formula 4a>

Li _7-xwz M1 _x M2 _w PS _6-z Cl _z

In the above formula, M1 is Cu, Ag, Mg or a combination thereof, M2 is Na, K or a combination thereof, 0<x<0.5, 0<w<0.5, 0<x+w<0.5, and 1≤ z≤2. In the above formula, for example, 0<x+w<0.3, 0<x+w<0.1, 0<x+w<0.05, 0<x+w<0.04, or 0<x+w<0.03.

The solid ion conductor compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by the following Formula 4b:

<Formula 4b>

Li _5.75-xw M1 _x M2 _w PS _4.75 Cl _1.25

In the above formula, M1 is Cu, Ag, Mg or a combination thereof, M2 is Na, K or a combination thereof, 0<x<0.05, 0<w<0.05, 0<x+w<0.05. In the above formula, for example, 0<x+w<0.3, 0<x+w<0.1, 0<x+w<0.05, 0<x+w<0.04, or 0<x+w<0.03.

The solid electrolyte compound represented by Formula 1 may be, for example, a solid electrolyte compound represented by Formula 5:

<Formula 5>

(Li _1-bc M1 _b M2 _c ) _7-z PS _6-z M3 _z

In the above formula, M1 is at least one element selected from Groups 2 and 11 of the periodic table, is a monovalent cation, M2 is at least one metal element other than Li selected from Group 1 of the periodic table, is a monovalent cation, and M3 is from Group 17 of the periodic table. It is one or more selected elements, -1 is an anion, and 0<b<0.1, 0<c<0.1, 0<b+c≤0.1, and 0≤z≤2. In the above formula, for example, 0<b<0.05, 0<c<0.05, and, for example, 0<b+c≤0.05, 0<b+c≤0.04, 0<b+c≤0.03, 0<b +c≤0.02, 0<b+c≤0.01, 0<b+c≤0.005, or 0<b+c≤0.002.

The compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by the following Formulas 5a to 5f:

<Formula 5a>

(Li _1-bc Cu _b Na _c ) _7-z PS _6-z M3 _z

<Formula 5b>

(Li _1-bc Ag _b Na _c ) _7-z PS _6-z M3 _z

<Formula 5c>

(Li _1-bc Mg _b Na _c ) _7-z PS _6-z M3 _z

<Formula 5d>

(Li _1-bc Cu _b K _c ) _7-z PS _6-z M3 _z

<Formula 5e>

(Li _1-bc Ag _b K _c ) _7-z PS _6-z M3 _z

<Formula 5f>

(Li _1-bc Mg _b K _c ) _7-z PS _6-z M3 _z

In the above formulas, M3 is ^{F -, Cl -, Br -} , I - or a combination thereof, 0 <b <0.1, 0 <b <0.1, 0 <b + c≤0.1 and a 0≤z≤2. In the above equations, for example, 0<b<0.05, 0<c<0.05, for example 0<b+c≤0.05, 0<b+c≤0.04, 0<b+c≤0.03, 0< b+c≤0.02, 0<b+c≤0.01, 0<b+c≤0.005, or 0<b+c≤0.002.

The compound represented by Formula 1 may be, for example, a solid ion conductor compound represented by the following formulas:

(Li _1-bc Cu _b Na _c ) _7-z PS _6-z Cl _z , (Li _1-bc Ag _b Na _c ) _7-z PS _6-z Cl _z , (Li _1-bc Mg _b Na _c ) _7-z PS _6-z Cl _z , (Li _1-bc Cu _b K _c ) _7-z PS _6-z Cl _z , (Li _1-bc Ag _b K _c ) _7-z PS _6-z Cl _z , (Li _1-bc Mg _b K _c ) _7-z PS _6-z Cl _z , (Li _1-bc Cu _b Na _c ) _7-z PS _6-z Br _z , (Li _1-bc Ag _b Na _c ) _7-z PS _6-z Br _z , (Li _1-bc Mg _b Na _c ) _7-z PS _6-z Br _z , (Li _1-bc Cu _b K _c ) _7-z PS _6-z Br _z , (Li _1-bc Ag _b K _c ) _7-z PS _6-z Br _z , (Li _1-bc Mg _b K _c ) _7-z PS _6-z Br _z , (Li _1-bc Cu _b Na _c ) _7-z PS _6-z I _z , (Li _1-bc Ag _b Na _c ) _7-z PS _6-z I _z , (Li _1-bc Mg _b Na _c ) _7-z PS _6-z I _z , (Li _1-bc Cu _b K _c ) _7-z PS _6-z I _z , (Li _1-bc Ag _b K _c ) _7-z PS _6-z I _z , (Li _1-bc Mg _b K _c ) _7-z PS _6-z I _z

_{In the above equations, 0<b<0.05, 0<c<0.05, 0<b+c} ≦0.05, and 0<z≦2. In the above formulas, for example, 0<b<0.04, 0<c<0.04, for example 0<b+c≤0.04, 0<b+c≤0.03, 0<b+c≤0.02, 0< b+c≤0.01, 0<b+c≤0.005, or 0<b+c≤0.002.

The solid ion conductor compound represented by Formula 1 may be, for example, specific solid electrolyte compounds represented by the following formulas.

(Li _5.73 Cu _0.01 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.72 Cu _0.02 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.02 Na _0.02 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.03 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.03 Na _0.02 ) PS _4.75 Cl _1.25 , (Li _5.69 Cu _0.03 Na _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Cu _0.06 Na _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Cu _0.03 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.63 Cu _0.06 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Cu _0.09 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Cu _0.06 Na _0.09 ) PS _4.75 Cl _1.25 , (Li _5.57 Cu _0.09 Na _0.09 ) PS _4.75 Cl _1.25 , (Li _5.51 Cu _0.12 Na _0.12 ) PS _4.75 Cl _1.25 , (Li _5.45 Cu _0.15 Na _0.15 ) PS _4.75 Cl _1.25 ,

(Li _5.73 Ag _0.01 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.72 Ag _0.02 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.02 Na _0.02 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.03 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.03 Na _0.02 ) PS _4.75 Cl _1.25 , (Li _5.69 Ag _0.03 Na _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Ag _0.06 Na _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Ag _0.03 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.63 Ag _0.06 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Ag _0.09 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Ag _0.06 Na _0.09 ) PS _4.75 Cl _1.25 , (Li _5.57 Ag _0.09 Na _0.09 ) PS _4.75 Cl _1.25 , (Li _5.51 Ag _0.12 Na _0.12 ) PS _4.75 Cl _1.25 , (Li _5.45 Ag _0.15 Na _0.15 ) PS _4.75 Cl _1.25 ,

(Li _5.73 Mg _0.01 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.72 Mg _0.02 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.02 Na _0.02 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.03 Na _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.03 Na _0.02 ) PS _4.75 Cl _1.25 , (Li _5.69 Mg _0.03 Na _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Mg _0.06 Na _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Mg _0.03 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.63 Mg _0.06 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Mg _0.09 Na _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Mg _0.06 Na _0.09 ) PS _4.75 Cl _1.25 , (Li _5.57 Mg _0.09 Na _0.09 )PS _4.75 Cl _1.25 , (Li _5.51 Mg _0.12 Na _0.12 ) PS _4.75 Cl _1.25 , (Li _5.45 Mg _0.15 Na _0.15 ) PS _4.75 Cl _1.25 ,(Li _5.73 Cu _0.01 K _0.01 )PS _4.75 Cl _1.25 , (Li _5.72 Cu _0.02 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.02 K _0.02 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.03 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Cu _0.03 K _0.02 ) PS _4.75 Cl _1.25 , (Li _5.69 Cu _0.03 K _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Cu _0.06 K _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Cu _0.03 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.63 Cu _0.06 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Cu _0.09 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Cu _0.06 K _0.09 ) PS _4.75 Cl _1.25 , (Li _5.57 Cu _0.09 K _0.09 ) PS _4.75 Cl _1.25 , (Li _5.51 Cu _0.12 K _0.12 ) PS _4.75 Cl _1.25 , (Li _5.45 Cu _0.15 K _0.15 ) PS _4.75 Cl _1.25 ,

(Li _5.73 Ag _0.01 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.72 Ag _0.02 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.02 K _0.02 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.03 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Ag _0.03 K _0.02 ) PS _4.75 Cl _1.25 , (Li _5.69 Ag _0.03 K _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Ag _0.06 K _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Ag _0.03 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.63 Ag _0.06 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Ag _0.09 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Ag _0.06 K _0.09 ) PS _4.75 Cl _1.25 , (Li _5.57 Ag _0.09 K _0.09 ) PS _4.75 Cl _1.25 , (Li _5.51 Ag _0.12 K _0.12 ) PS _4.75 Cl _1.25 , (Li _5.45 Ag _0.15 K _0.15 ) PS _4.75 Cl _1.25 ,

(Li _5.73 Mg _0.01 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.72 Mg _0.02 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.02 K _0.02 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.03 K _0.01 ) PS _4.75 Cl _1.25 , (Li _5.71 Mg _0.03 K _0.02 ) PS _4.75 Cl _1.25 , (Li _5.69 Mg _0.03 K _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Mg _0.06 K _0.03 ) PS _4.75 Cl _1.25 , (Li _5.66 Mg _0.03 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.63 Mg _0.06 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Mg _0.09 K _0.06 ) PS _4.75 Cl _1.25 , (Li _5.60 Mg _0.06 K _0.09 ) PS _4.75 Cl _1.25 , (Li _5.57 Mg _0.09 K _0.09 ) PS _4.75 Cl _1.25 , (Li _5.51 Mg _0.12 K _0.12 ) PS _4.75 Cl _1.25 , (Li _5.45 Mg _0.15 K _0.15 ) PS _4.75 Cl _1.25 ,

(Li _5.73 Cu _0.01 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.72 Cu _0.02 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.02 Na _0.02 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.03 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.03 Na _0.02 ) PS _4.75 Br _1.25 , (Li _5.69 Cu _0.03 Na _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Cu _0.06 Na _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Cu _0.03 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.63 Cu _0.06 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Cu _0.09 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Cu _0.06 Na _0.09 ) PS _4.75 Br _1.25 , (Li _5.57 Cu _0.09 Na _0.09 ) PS _4.75 Br _1.25 , (Li _5.51 Cu _0.12 Na _0.12 ) PS _4.75 Br _1.25 , (Li _5.45 Cu _0.15 Na _0.15 ) PS _4.75 Br _1.25 ,

(Li _5.73 Ag _0.01 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.72 Ag _0.02 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.02 Na _0.02 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.03 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.03 Na _0.02 ) PS _4.75 Br _1.25 , (Li _5.69 Ag _0.03 Na _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Ag _0.06 Na _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Ag _0.03 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.63 Ag _0.06 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Ag _0.09 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Ag _0.06 Na _0.09 ) PS _4.75 Br _1.25 , (Li _5.57 Ag _0.09 Na _0.09 )PS _4.75 Br _1.25 , (Li _5.51 Ag _0.12 Na _0.12 ) PS _4.75 Br _1.25 , (Li _5.45 Ag _0.15 Na _0.15 ) PS _4.75 Br _1.25 ,

(Li _5.73 Mg _0.01 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.72 Mg _0.02 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.02 Na _0.02 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.03 Na _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.03 Na _0.02 ) PS _4.75 Br _1.25 , (Li _5.69 Mg _0.03 Na _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Mg _0.06 Na _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Mg _0.03 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.63 Mg _0.06 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Mg _0.09 Na _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Mg _0.06 Na _0.09 ) PS _4.75 Br _1.25 , (Li _5.57 Mg _0.09 Na _0.09 ) PS _4.75 Br _1.25 , (Li _5.51 Mg _0.12 Na _0.12 ) PS _4.75 Br _1.25 , (Li _5.45 Mg _0.15 Na _0.15 ) PS _4.75 Br _1.25 ,

(Li _5.73 Cu _0.01 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.72 Cu _0.02 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.02 K _0.02 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.03 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Cu _0.03 K _0.02 ) PS _4.75 Br _1.25 , (Li _5.69 Cu _0.03 K _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Cu _0.06 K _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Cu _0.03 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.63 Cu _0.06 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Cu _0.09 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Cu _0.06 K _0.09 ) PS _4.75 Br _1.25 , (Li _5.57 Cu _0.09 K _0.09 ) PS _4.75 Br _1.25 , (Li _5.51 Cu _0.12 K _0.12 ) PS _4.75 Br _1.25 , (Li _5.45 Cu _0.15 K _0.15 ) PS _4.75 Br _1.25 ,

(Li _5.73 Ag _0.01 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.72 Ag _0.02 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.02 K _0.02 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.03 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Ag _0.03 K _0.02 ) PS _4.75 Br _1.25 , (Li _5.69 Ag _0.03 K _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Ag _0.06 K _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Ag _0.03 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.63 Ag _0.06 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Ag _0.09 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Ag _0.06 K _0.09 ) PS _4.75 Br _1.25 , (Li _5.57 Ag _0.09 K _0.09 )PS _4.75 Br _1.25 , (Li _5.51 Ag _0.12 K _0.12 ) PS _4.75 Br _1.25 , (Li _5.45 Ag _0.15 K _0.15 ) PS _4.75 Br _1.25 ,

(Li _5.73 Mg _0.01 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.72 Mg _0.02 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.02 K _0.02 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.03 K _0.01 ) PS _4.75 Br _1.25 , (Li _5.71 Mg _0.03 K _0.02 ) PS _4.75 Br _1.25 , (Li _5.69 Mg _0.03 K _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Mg _0.06 K _0.03 ) PS _4.75 Br _1.25 , (Li _5.66 Mg _0.03 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.63 Mg _0.06 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Mg _0.09 K _0.06 ) PS _4.75 Br _1.25 , (Li _5.60 Mg _0.06 K _0.09 ) PS _4.75 Br _1.25 , (Li _5.57 Mg _0.09 K _0.09 )PS _4.75 Br _1.25 , (Li _5.51 Mg _0.12 K _0.12 ) PS _4.75 Br _1.25 , (Li _5.45 Mg _0.15 K _0.15 ) PS _4.75 Br _1.25 ,(Li _5.73 Cu _0.01 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.72 Cu _0.02 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.02 Na _0.02 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.03 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.03 Na _0.02 ) PS _4.75 I _1.25 , (Li _5.69 Cu _0.03 Na _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Cu _0.06 Na _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Cu _0.03 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.63 Cu _0.06 Na _0.06 ) PS _4.75 I _1.25 , ( Li _5.60 Cu _0.09 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Cu _0.06 Na _0.09 ) PS _4.75 I _1.25 , (Li _5.57 Cu _0.09 Na _0.09 ) PS _4.75 I _1.25 , (Li _5.51 Cu _0.12 Na _0.12 ) PS _4.75 I _1.25 , (Li _5.45 Cu _0.15 Na _0.15 ) PS _4.75 I _1.25 ,

(Li _5.73 Ag _0.01 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.72 Ag _0.02 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.02 Na _0.02 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.03 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.03 Na _0.02 ) PS _4.75 I _1.25 , (Li _5.69 Ag _0.03 Na _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Ag _0.06 Na _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Ag _0.03 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.63 Ag _0.06 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Ag _0.09 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Ag _0.06 Na _0.09 ) PS _4.75 I _1.25 , (Li _5.57 Ag _0.09 Na _0.09 )PS _4.75 I _1.25 , (Li _5.51 Ag _0.12 Na _0.12 ) PS _4.75 I _1.25 , (Li _5.45 Ag _0.15 Na _0.15 ) PS _4.75 I _1.25 ,

(Li _5.73 Mg _0.01 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.72 Mg _0.02 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.02 Na _0.02 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.03 Na _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.03 Na _0.02 ) PS _4.75 I _1.25 , (Li _5.69 Mg _0.03 Na _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Mg _0.06 Na _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Mg _0.03 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.63 Mg _0.06 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Mg _0.09 Na _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Mg _0.06 Na _0.09 ) PS _4.75 I _1.25 , (Li _5.57 Mg _0.09 Na _0.09 ) PS _4.75 I _1.25 , (Li _5.51 Mg _0.12 Na _0.12 ) PS _4.75 I _1.25 , (Li _5.45 Mg _0.15 Na _0.15 ) PS _4.75 I _1.25 ,

(Li _5.73 Cu _0.01 K _0.01 ) PS _4.75 I _1.25 , (Li _5.72 Cu _0.02 K _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.02 K _0.02 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.03 K _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Cu _0.03 K _0.02 ) PS _4.75 I _1.25 , (Li _5.69 Cu _0.03 K _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Cu _0.06 K _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Cu _0.03 K _0.06 ) PS _4.75 I _1.25 , (Li _5.63 Cu _0.06 K _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Cu _0.09 K _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Cu _0.06 K _0.09 ) PS _4.75 I _1.25 , (Li _5.57 Cu _0.09 K _0.09 )PS _4.75 I _1.25 , (Li _5.51 Cu _0.12 K _0.12 ) PS _4.75 I _1.25 , (Li _5.45 Cu _0.15 K _0.15 ) PS _4.75 I _1.25 ,

(Li _5.73 Ag _0.01 K _0.01 ) PS _4.75 I _1.25 , (Li _5.72 Ag _0.02 K _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.02 K _0.02 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.03 K _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Ag _0.03 K _0.02 ) PS _4.75 I _1.25 , (Li _5.69 Ag _0.03 K _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Ag _0.06 K _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Ag _0.03 K _0.06 ) PS _4.75 I _1.25 , (Li _5.63 Ag _0.06 K _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Ag _0.09 K _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Ag _0.06 K _0.09 ) PS _4.75 I _1.25 , (Li _5.57 Ag _0.09 K _0.09 )PS _4.75 I _1.25 , (Li _5.51 Ag _0.12 K _0.12 ) PS _4.75 I _1.25 , (Li _5.45 Ag _0.15 K _0.15 ) PS _4.75 I _1.25 ,

(Li _5.73 Mg _0.01 K _0.01 ) PS _4.75 I _1.25 , (Li _5.72 Mg _0.02 K _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.02 K _0.02 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.03 K _0.01 ) PS _4.75 I _1.25 , (Li _5.71 Mg _0.03 K _0.02 ) PS _4.75 I _1.25 , (Li _5.69 Mg _0.03 K _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Mg _0.06 K _0.03 ) PS _4.75 I _1.25 , (Li _5.66 Mg _0.03 K _0.06 ) PS _4.75 I _1.25 , (Li _5.63 Mg _0.06 K _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Mg _0.09 K _0.06 ) PS _4.75 I _1.25 , (Li _5.60 Mg _0.06 K _0.09 ) PS _4.75 I _1.25 , (Li _5.57 Mg _0.09 K _0.09 )PS _4.75 I _1.25 , (Li _5.51 Mg _0.12 K _0.12 ) PS _4.75 I _1.25 , (Li _5.45 Mg _0.15 K _0.15 ) PS _4.75 I _1.25 ,

In one embodiment, a part of S in the solid ion conductor compound represented by Formula 1 may be additionally substituted _{with SO 4.}

In the solid ion conductor compound represented by Formula 1, a solid ion conductor compound in which a part of S _{is additionally substituted with SO 4} may be represented by, for example, Formula 6:

<Formula 6>

Li _a M1 _x M2 _w PS _yp (SO ₄ ) _p M3 _z

In the above formula, M1 is one or more elements selected from Groups 2 and 11 of the periodic table, M2 is one or more metal elements other than Li selected from Group 1 of the periodic table, M3 is one or more elements selected from Group 17 of the periodic table, 4≤a≤ 8, 0<x<0.5, 0≦w<0.5, 3≦y≦7, 0<p<2, and 0≦z≦2. In the above formula, for example, 0<p≤1.5, 0<p≤1.0, 0<p≤0.5, 0<p≤0.25, 0<p≤0.2, 0<p≤0.1, 0<p≤0.075, 0 <p≤0.05, or 0<p≤0.03.

The solid ion conductor compound represented by Formula 1 provides improved lithium ion conductivity. The solid ion conductor compound represented by Formula 1 is at room temperature, for example, at about 25°C, 0.5 mS/cm or more, 0.6 mS/cm or more, 1.0 mS/cm or more, 1.5 mS/cm or more, 2.0 mS/cm or more, It provides an ion conductivity of 2.5 mS/cm or more, or 3.0 mS/cm or more. The solid ion conductor compound represented by Formula 1 is at room temperature, for example, 0.5 to 500 mS/cm, 0.6 to 500 mS/cm, 1.0 to 400 mS/cm, 1.5 to 300 mS/cm, 2.0 to It provides an ionic conductivity of 200 mS/cm, 2.5 to 100 mS/cm, or 3.0 to 100 mS/cm or more. Thus, the anode; cathode; And a solid ion conductor compound represented by Chemical Formula 1 disposed between the positive electrode and the negative electrode, by effectively transferring ions between the positive electrode and the negative electrode, thereby reducing internal resistance between the positive electrode and the negative electrode. Ion conductivity can be measured using a DC polarization method. Alternatively, the ionic conductivity can be measured using a complex impedance method.

The solid ion conductor compound represented by Formula 1 may have an ion conductivity retention rate of 70% or more after 10 days in a dry condition in an air atmosphere having a dew point of less than -60°C. The ionic conductivity retention rate may be expressed by, for example, Equation 1 below. In Equation 1 below, the initial ionic conductivity of the solid ion conductor compound refers to the ionic conductivity of the solid ion conductor compound before storage under dry conditions.

<Equation 1>

Ion conductivity retention rate = [Ion conductivity of the solid ion conductor compound after 10 days / Ion conductivity of the initial solid ion conductor compound] × 100

The solid ion conductor compound represented by Formula 1 belongs to, for example, a cubic crystal system, and more specifically, may belong to the F-43m space group. In addition, the solid ion conductor compound represented by Formula 1 may be an azirodite-type sulfide having an azirodite-type crystal structure. The solid ion conductor compound represented by Formula 1 has improved lithium ion conductivity by substituting one or more ^{of M +} cation element, M ^{2 +} cation element, or Me ⁺ cation element in part of the lithium site in the azirodite crystal structure. And electrochemical stability to lithium metal can be provided at the same time.

The solid ion conductor compound represented by Formula 1 is, for example, 25.48°±0.50°, 30.01°±0.50°, 31.38°±0.50°, 46.0°±1.0°, 48.5°±1.0°, in the XRD spectrum using CuKα rays. It may have a peak at the position of 53.0°±1.0°. Since the solid ion conductor compound represented by Formula 1 has an azirodite structure, it may have such a peak in the XRD spectrum using CuKα rays.

The solid ion conductor compound represented by Formula 1 is the peak intensity (Ib) at the diffraction angle 2θ = 53.0°±1.0° relative to the peak intensity (Ia) at the diffraction angle 2θ = 46.0°±1.0° in the XRD spectrum using CuKα rays. ), the peak intensity ratio Ia/Ib may be 1 or less, 0.95 or less, 0.90 or less, 0.85 or less, or 0.80 or less. By having a peak intensity ratio in this range, the ionic conductivity of the solid ion conductor compound may be further improved.

The solid ion conductor compound represented by Formula 1 has a peak half width (FWHM) of 0.30° or less, 0.28° or less, 0.26° or less, and 0.24° at diffraction angle 2θ=46.0°±1.0° in the XRD spectrum using CuKα rays. It may be 0.22° or less, 0.20° or less, 0.18° or less, 0.16° or less, 0.14° or less, 0.12° or less, or 0.10° or less. By having the peak half width in this range, the ionic conductivity of the solid ion conductor compound may be further improved.

[Solid electrolyte]

The solid electrolyte according to another embodiment includes the solid ion conductor compound represented by Formula 1 above. The solid electrolyte may have high ionic conductivity and high chemical stability by including such a solid ion conductor compound. The solid electrolyte including the solid ion conductor compound represented by Formula 1 may provide improved stability to air and electrochemical stability to lithium metal. Therefore, the solid ion conductor compound represented by Formula 1 may be used as a solid electrolyte for an electrochemical cell, for example.

The solid electrolyte may further include a conventional general solid electrolyte in addition to the solid ion conductor compound represented by Formula 1. For example, a conventional general sulfide-based solid electrolyte and/or an oxide-based solid electrolyte may be additionally included. Conventional solid ion conductor compounds additionally included are, for example, Li ₂ O-Al ₂ O ₃ -TiO ₂ -P ₂ O ₅ (LATP), LISICON (Lithium Super Ionic Conductor), LIPON (Li _3-y PO _{4 -x} N _x , 0<y<3, 0<x<4), Thio-LISICON(Li _3.25 Ge _0.25 P _0.75 S ₄ ), Li ₂ S, Li ₂ SP ₂ S ₅ , Li ₂ S-SiS ₂ , It may be Li ₂ S-GeS ₂ , Li ₂ SB ₂ S ₅ , and Li ₂ S-Al ₂ S _5, and the like, but is not limited thereto, and any one that can be used in the art may be used.

The solid electrolyte may be in the form of a powder or a molded product. The solid electrolyte in the form of a molded product may be in the form of, for example, a pellet, a sheet, or a thin film, but is not limited thereto and may have various forms depending on the intended use.

[Electrochemical cell]

An electrochemical cell according to another embodiment includes: an anode layer including a cathode active material layer; A negative electrode layer including a negative electrode active material layer; And an electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and the positive electrode active material layer and/or the electrolyte layer includes a solid ion conductor compound represented by Chemical Formula 1. When the electrochemical cell contains the solid ion conductor compound represented by Formula 1, the lithium ion conductivity of the electrochemical cell and stability to lithium metal are improved.

The electrochemical cell may be, for example, an all-solid secondary battery, a liquid electrolyte-containing secondary battery, or a lithium-air battery, but is not limited thereto, and any electrochemical cell that can be used in the art may be used.

Hereinafter, the all-solid secondary battery will be described in more detail.

[All-solid secondary battery: Type 1]

The all-solid secondary battery may include a solid ion conductor compound represented by Formula 1.

The all-solid secondary battery includes, for example, a positive electrode layer including a positive electrode active material layer; A negative electrode layer including a negative electrode active material layer; And an electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and the positive electrode active material layer and/or the electrolyte layer may include a solid ion conductor compound represented by Chemical Formula 1.

An all-solid secondary battery according to an embodiment may be prepared as follows.

(Solid electrolyte layer)

First, a solid electrolyte layer is prepared.

The solid electrolyte layer is prepared by mixing and drying the solid ion conductor compound represented by Formula 1 and a binder, or by rolling the powder of the solid ion conductor compound represented by Formula 1 in a certain form at a pressure of 1 ton to 10 ton. I can. The solid ion conductor compound represented by Formula 1 is used as the solid electrolyte.

The average particle diameter of the solid electrolyte may be, for example, 0.5um to 20um. Since the solid electrolyte has such an average particle diameter, binding properties are improved in the process of forming the sintered body, so that the ionic conductivity and life characteristics of the solid electrolyte particles can be improved.

The thickness of the solid electrolyte layer may be 10 um to 200 um. When the solid electrolyte layer has such a thickness, a sufficient movement speed of lithium ions is ensured, and as a result, high ionic conductivity can be obtained.

The solid electrolyte layer may further include a solid electrolyte such as a conventional sulfide-based solid electrolyte and/or an oxide-based solid electrolyte in addition to the solid ion conductor compound represented by Formula 1.

The conventional sulfide-based solid electrolyte may include, for example, lithium sulfide, silicon sulfide, phosphorus sulfide, boron sulfide, or a combination thereof. Conventional sulfide-based solid electrolyte particles may include Li ₂ S, P ₂ S ₅ , SiS ₂ , GeS ₂ , B ₂ S ₃ or a combination thereof. The conventional sulfide-based solid electrolyte particles may be Li ₂ S or P ₂ S ₅ . Conventional sulfide-based solid electrolyte particles are known to have higher lithium ion conductivity than other inorganic compounds. For example, a conventional sulfide-based solid electrolyte includes Li ₂ S and P ₂ S ₅ . When the sulfide solid electrolyte material constituting the conventional sulfide-based solid electrolyte contains Li ₂ SP ₂ S ₅ , _{the mixing molar ratio of Li 2} S to P ₂ S ₅ is, for example, from about 50:50 to about 90:10. It can be a range. In addition, Li ₃ PO ₄ , halogen, halogen compound, Li _2+2x Zn _1??x GeO ₄ ("LISICON"), Li _3+y PO _4-x N _{x (} "LIPON"), Li _3.25 Ge _0.25 P _0.75 S ₄ ("ThioLISICON"), Li ₂ O-Al ₂ O ₃ -TiO ₂ -P ₂ O _{5 (} "LATP"), etc. to Li ₂ SP ₂ S ₅ , SiS ₂ , GeS ₂ , B ₂ S ₃ , Alternatively, an inorganic solid electrolyte prepared by adding to the inorganic solid electrolyte of a combination thereof may be used as a conventional sulfide solid electrolyte. Non-limiting examples of conventional sulfide solid electrolyte materials include Li ₂ SP ₂ S ₅ ; Li ₂ SP ₂ S ₅ -LiX (X is a halogen element); Li ₂ SP ₂ S ₅ -Li ₂ O; Li ₂ SP ₂ S ₅ -Li ₂ O-LiI; Li ₂ S-SiS ₂ ; Li ₂ S-SiS ₂ -LiI; Li ₂ S-SiS ₂ -LiBr; Li ₂ S-SiS ₂ -LiCl; Li ₂ S-SiS ₂ -B ₂ S ₃ -LiI; Li ₂ S-SiS ₂ -P ₂ S ₅ -LiI; Li ₂ SB ₂ S ₃ ; Li ₂ S -P ₂ S ₅ -Z _m S _n (m and n are positive numbers and Z is Ge, Zn or G); Li ₂ S-GeS ₂ ; Li ₂ S-SiS ₂ -Li ₃ PO ₄ ; And Li ₂ S-SiS ₂ -Li _p MO _q (wherein p and q are positive numbers, and M is P, Si, Ge, B, Al, Ga, or In). In this regard, the conventional sulfide-based solid electrolyte material is a melt quenching method and a mechanical milling method of _{starting materials (eg, Li 2} S, P ₂ S _{5, etc.) of a sulfide-based solid electrolyte material.} It can be produced by processing by or the like. In addition, a process of calcinations may be performed after the treatment.

The binder included in the solid electrolyte layer is, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, and polyvinyl alcohol. And the like, but not limited thereto, and any one used as a binder in the art may be used. The binder of the solid electrolyte layer may be the same as or different from the binder of the anode layer and the cathode layer.

(Anode layer)

Next, an anode layer is prepared.

The positive electrode layer may be prepared by forming a positive electrode active material layer including a positive electrode active material on the current collector. The average particle diameter of the positive electrode active material may be, for example, 2 um to 10 um.

Any positive electrode active material may be used without limitation as long as it is commonly used in a secondary battery. For example, it may be a lithium transition metal oxide, a transition metal sulfide, or the like. For example, one or more of a complex oxide of a metal and lithium selected from cobalt, manganese, nickel, and combinations thereof may be used, and a specific example thereof is Li _a A _1-b B _b D ₂ (the above Where 0.90≦a≦1.8, and 0≦b≦0.5); Li _a E _1-b B _b O _2-c D _c (in the above formula, 0.90≦a≦1.8, 0≦b≦0.5, 0≦c≦0.05); LiE _2-b B _b O _4-c D _c (where 0≦b≦0.5, 0≦c≦0.05); Li _a Ni _1-bc Co _b B _c D _α (wherein, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α ≤ 2); Li _a Ni _1-bc Co _b B _c O _2-α F _α (in the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _1-bc Co _b B _c O _2-α F ₂ (wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _1-bc Mn _b B _c D _α (wherein, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α ≤ 2); Li _a Ni _1-bc Mn _b B _c O _2-α F _α (in the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _1-bc Mn _b B _c O _2-α F ₂ (in the above formula, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 <α <2); Li _a Ni _b E _c G _d O ₂ (in the above formula, 0.90≦a≦1.8, 0≦b≦0.9, 0≦c≦0.5, 0.001≦d≦0.1); Li _a Ni _b Co _c Mn _d GeO ₂ (in the above formula, 0.90≦a≦1.8, 0≦b≦0.9, 0≦c≦0.5, 0≦d≦0.5, 0.001≦e≦0.1); Li _a NiG _b O ₂ (in the above formula, 0.90≦a≦1.8, 0.001≦b≦0.1); Li _a CoG _b O ₂ (wherein, 0.90≦a≦1.8, 0.001≦b≦0.1); Li _a MnG _b O ₂ (wherein, 0.90≦a≦1.8, 0.001≦b≦0.1); Li _a Mn ₂ G _b O ₄ (In the above formula, 0.90≦a≦1.8, 0.001≦b≦0.1.); QO ₂ ; QS ₂ ; LiQS ₂ ; V ₂ O ₅ ; LiV ₂ O ₂ ; LiIO ₂ ; LiNiVO ₄ ; Li _(3-f) J ₂ (PO ₄ ) ₃ (0≦f≦2); Li _(3-f) Fe ₂ (PO ₄ ) ₃ (0≦f≦2); A compound represented by any one of the formulas of LiFePO _{4 may be used.} In the above formula, A is Ni, Co, Mn, or a combination thereof; B is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or combinations thereof; D is O, F, S, P, or a combination thereof; E is Co, Mn, or a combination thereof; F is F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; Q is Ti, Mo, Mn, or a combination thereof; I is Cr, V, Fe, Sc, Y, or a combination thereof; J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof. For example, LiCoO ₂ , LiMn _x O _2x (x=1, 2), LiNi _1-x Mn _x O _2x (0<x<1), Ni _1-xy Co _x Mn _y O ₂ (0≤x≤ 0.5, 0≤y≤0.5), Ni _1-xy Co _x Al _y O ₂ (0≤x≤0.5, 0≤y≤0.5), LiFePO ₄ , TiS ₂ , FeS ₂ , TiS ₃ , FeS _3, etc. In these compounds, A is Ni, Co, Mn, or a combination thereof; B is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or combinations thereof; D is O, F, S, P, or a combination thereof; E is Co, Mn, or a combination thereof; F is F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; Q is Ti, Mo, Mn, or a combination thereof; I is Cr, V, Fe, Sc, Y, or a combination thereof; J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof. It is also possible to use a compound having a coating layer added on the surface of such a compound, or a mixture of the above-described compound and a compound having a coating layer added thereto. The coating layer added to the surface of such a compound includes, for example, an oxide of a coating element, a hydroxide, an oxyhydroxide of a coating element, an oxycarbonate of a coating element, or a coating element compound of a hydroxycarbonate of a coating element. The compound constituting this coating layer is amorphous or crystalline. Coating elements included in the coating layer are Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or a mixture thereof. The method of forming the coating layer is selected within a range that does not adversely affect the physical properties of the positive electrode active material. The coating method is, for example, spray coating, dipping method, or the like. A detailed description of the coating method will be omitted because it is a content that can be well understood by those engaged in the relevant field.

The positive electrode active material includes, for example, a lithium salt of a transition metal oxide having a layered rock salt type structure among the lithium transition metal oxides described above. The "layered rock salt type structure" is, for example, in the direction of a cubic rock salt type structure, in which an oxygen atom layer and a metal atom layer are alternately and regularly arranged, whereby each atomic layer is a two-dimensional plane. It is a structure that forms. "Cubic rock salt structure" refers to a NaCl type structure, which is a kind of crystal structure, and specifically, face centered cubic lattice (fcc) forming each of cations and anions is unit lattice (unit lattice). It represents a structure that is arranged shifted by 1/2 of the ridge of ). The lithium transition metal oxide having such a layered rock salt structure is, for example, LiNi _x Co _y Al _z O ₂ (NCA) or LiNi _x Co _y Mn _z O ₂ (NCM) (0 <x <1, 0 <y It is a ternary lithium transition metal oxide such as <1, 0 <z <1, x + y + z = 1). When the positive electrode active material contains a ternary lithium transition metal oxide having a layered rock salt structure, the energy density and thermal stability of the all-solid secondary batteries 1 and 1 are further improved.

As described above, the positive electrode active material may be covered by a coating layer. The coating layer may be any known coating layer of the positive electrode active material of an all-solid secondary battery. The coating layer is, for example, Li ₂ O-ZrO ₂ (LZO) or the like.

When the positive electrode active material contains nickel (Ni) as a ternary lithium transition metal oxide such as NCA or NCM, it is possible to decrease the metal elution of the positive electrode active material in a charged state by increasing the capacity density of the all-solid secondary battery. . As a result, the cycle characteristics in the charged state of the all-solid secondary battery are improved.

The shape of the positive electrode active material is, for example, a particle shape such as a spherical sphere or an elliptical sphere. The particle diameter of the positive electrode active material is not particularly limited, and is within a range applicable to the positive electrode active material of a conventional all-solid secondary battery. The content of the positive electrode active material in the positive electrode layer is also not particularly limited, and is within a range applicable to the positive electrode layer of a conventional all-solid secondary battery. The content of the positive electrode active material in the positive electrode active material layer may be, for example, 50 to 95% by weight.

The positive electrode active material layer may additionally include a solid ion conductor compound represented by Chemical Formula 1.

The positive electrode active material layer may include a binder. The binder is, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, and the like.

The positive electrode active material layer may include a conductive material. The conductive material is, for example, graphite, carbon black, acetylene black, Ketjen black, carbon fiber, metal powder, and the like.

In addition to the above-described positive electrode active material, solid electrolyte, binder, and conductive material, the positive electrode active material layer may further include additives such as a filler, a coating agent, a dispersant, and an ion conductive auxiliary agent.

As a filler, a coating agent, a dispersant, an ion conductive auxiliary agent, etc. that may be included in the positive electrode active material layer, a known material generally used for an electrode of an all-solid secondary battery may be used.

The positive electrode current collector is, for example, aluminum (Al), indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), A plate or foil made of zinc (Zn), germanium (Ge), lithium (Li), or an alloy thereof is used. The positive electrode current collector can be omitted.

The positive electrode current collector may further include a carbon layer disposed on one or both surfaces of the metal substrate. Since the carbon layer is additionally disposed on the metal substrate, the metal of the metal substrate may be prevented from being corroded by the solid electrolyte included in the positive electrode layer, and the interface resistance between the positive electrode active material layer layer and the positive electrode current collector may be reduced. The thickness of the carbon layer may be, for example, 1 um to 5 um. If the thickness of the carbon layer is too thin, it may be difficult to completely block contact between the metal substrate and the solid electrolyte. If the carbon layer is too thick, the energy density of the all-solid secondary battery may decrease. The carbon layer may include amorphous carbon, crystalline carbon, or the like.

(Cathode layer)

Next, a cathode layer is prepared.

The negative electrode layer may be prepared in the same manner as the positive electrode layer, except that a negative electrode active material is used instead of the positive electrode active material. The negative electrode layer may be prepared by forming a negative electrode active material layer including a negative electrode active material on the negative electrode current collector.

The negative electrode active material layer may additionally include a solid ion conductor compound represented by Formula 1 described above.

The negative electrode active material may be a lithium metal, a lithium metal alloy, or a combination thereof.

The anode active material layer may further include a conventional anode active material in addition to lithium metal, lithium metal alloy, or a combination thereof. The conventional negative electrode active material may include, for example, one or more selected from the group consisting of a metal alloyable with lithium, a transition metal oxide, a non-transition metal oxide, and a carbon-based material. Metal alloyable with lithium is, for example, Ag, Si, Sn, Al, Ge, Pb, Bi, Sb Si-Y alloy (where Y is an alkali metal, alkaline earth metal, group 13 element, group 14 element, transition metal, rare earth Element or a combination element thereof, not Si), Sn-Y alloy (the Y is an alkali metal, alkaline earth metal, group 13 element, group 14 element, transition metal, rare earth element, or a combination element thereof, but not Sn ), etc. The element Y is Mg, Ca, Sr, Ba, Ra, Sc, Y, Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg, Tc, Re, Bh, Fe, Pb, Ru, Os, Hs, Rh, Ir, Pd, Pt, Cu, Ag, Au, Zn, Cd, B, Al, Ga, Sn, In, Ti, Ge, P, As, Sb, Bi, S, It may be Se, Te, Po, or a combination thereof. The transition metal oxide may be, for example, lithium titanium oxide, vanadium oxide, lithium vanadium oxide, or the like. The non-transition metal oxide may be, for example, SnO ₂ , SiO _x (0<x<2), and the like. The carbon-based material can be, for example, crystalline carbon, amorphous carbon, or mixtures thereof. Crystalline carbon may be graphite such as amorphous, plate-like, flake, spherical or fibrous natural graphite or artificial graphite, and the amorphous carbon is soft carbon (low-temperature calcined carbon) or hard carbon. ), mesophase pitch carbide, fired coke, and the like.

4, an all-solid secondary battery 40 according to an embodiment includes a solid electrolyte layer 30, an anode layer 10 disposed on one surface of the solid electrolyte layer 30, and a solid electrolyte layer 30. It includes a cathode layer 20 disposed on the other side. The positive electrode layer 30 includes a positive electrode active material layer 12 in contact with the solid electrolyte layer 30 and a positive electrode current collector 11 in contact with the positive electrode active material layer 12, and the negative electrode layer 20 includes a solid electrolyte layer 30 ) And a negative electrode active material layer 22 in contact with the negative electrode active material layer 22 and a negative electrode current collector 21 in contact with the negative electrode active material layer 22. The all-solid secondary battery 40 includes, for example, a positive electrode active material layer 12 and a negative electrode active material layer 22 formed on both sides of the solid electrolyte layer 30, and the positive electrode active material layer 12 and the negative electrode active material layer 22 ) By forming the positive electrode current collector 11 and the negative electrode current collector 21, respectively, to complete the solid-state secondary battery 30. Alternatively, the negative electrode active material layer 22, the solid electrolyte layer 30, the positive electrode active material layer 12, and the positive electrode current collector 11 are sequentially stacked on the negative electrode current collector 21 to form an all-solid secondary battery 40. Is completed.

[All-solid secondary battery: 2nd type]

5 to 6, the all-solid secondary battery 1 includes, for example, a positive electrode layer 10 including a positive electrode active material layer 12 disposed on the positive electrode current collector 11; A negative electrode layer 20 including a negative electrode active material layer 22 disposed on the negative electrode current collector 21; And an electrolyte layer 30 disposed between the positive electrode layer 10 and the negative electrode layer 20, wherein the positive electrode active material layer 12 and/or the electrolyte layer 30 comprises a solid ion conductor compound represented by Formula 1 Can include.

The all-solid secondary battery according to another embodiment may be prepared as follows.

The positive electrode layer and the solid electrolyte layer are manufactured in the same manner as the all-solid secondary battery described above.

(Cathode layer)

Next, a cathode layer is prepared.

5 to 6, the negative electrode layer 20 includes a negative electrode current collector 21 and a negative electrode active material layer 22 disposed on the negative electrode current collector 21, and the negative electrode active material layer 22 is, for example, For example, it includes a negative electrode active material and a binder.

The negative electrode active material included in the negative electrode active material layer 22 has, for example, a particle shape. The average particle diameter of the negative electrode active material having a particle shape is, for example, 4um or less, 3um or less, 2um or less, 1um or less, or 900nm or less. The average particle diameter of the negative electrode active material having a particle shape is, for example, 10nm to 4um or less, 10nm to 3um or less, 10nm to 2um or less, 10nm to 1um or less, or 10nm to 900nm or less. Since the negative electrode active material has an average particle diameter within this range, it may be easier to reversibly absorb and/or desorb lithium during charging and discharging. The average particle diameter of the negative electrode active material is, for example, a median diameter (D50) measured using a laser particle size distribution meter.

The anode active material included in the anode active material layer 22 includes, for example, at least one selected from a carbon-based anode active material and a metal or metalloid anode active material.

The carbon-based negative active material is particularly amorphous carbon. Amorphous carbon is, for example, carbon black (CB), acetylene black (AB), furnace black (FB), ketjen black (KB), graphene. ), and the like, but are not necessarily limited thereto, and any one classified as amorphous carbon in the art may be used. Amorphous carbon has no crystallinity or is very low crystallinity, and is distinguished from crystalline carbon or graphite-based carbon.

Metal or metalloid anode active materials include gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). ) Includes at least one selected from the group consisting of, but is not necessarily limited thereto, and any material used as a metal anode active material or a metalloid anode active material forming an alloy or compound with lithium in the art may be used. For example, since nickel (Ni) does not form an alloy with lithium, it is not a metal negative electrode active material.

The anode active material layer 22 includes a kind of anode active material from among these anode active materials, or includes a mixture of a plurality of different anode active materials. For example, the anode active material layer 22 contains only amorphous carbon, or gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi) ), tin (Sn), and zinc (Zn). Alternatively, the anode active material layer 22 is amorphous carbon, gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin ( Sn) and zinc (Zn) include a mixture with one or more selected from the group consisting of. The mixing ratio of a mixture of amorphous carbon and gold is a weight ratio, for example, 10:1 to 1:2, 5:1 to 1:1, or 4:1 to 2:1. It is selected according to the characteristics of the solid secondary battery 1. When the negative electrode active material has such a composition, the cycle characteristics of the all-solid secondary battery 1 are further improved.

The negative electrode active material included in the negative electrode active material layer 22 includes, for example, a mixture of first particles made of amorphous carbon and second particles made of metal or metalloid. Metals or metalloids are, for example, gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn ) And zinc (Zn), and the like. Metalloids are otherwise semiconductors. The content of the second particles is 8 to 60% by weight, 10 to 50% by weight, 15 to 40% by weight, or 20 to 30% by weight, based on the total weight of the mixture. When the second particles have a content in this range, for example, the cycle characteristics of the all-solid secondary battery 1 are further improved.

The binder included in the negative electrode active material layer 22 is, for example, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, vinylidene fluoride/ Hexafluoropropylene copolymer, polyacrylonitrile, polymethyl methacrylate, and the like, but are not necessarily limited thereto, and any one used as a binder in the art may be used. The binder may be composed of a single or a plurality of different binders.

The anode active material layer 22 is stabilized on the anode current collector 21 by the anode active material layer 22 including the binder. In addition, cracking of the negative electrode active material layer 22 is suppressed despite a change in volume and/or a relative position of the negative electrode active material layer 22 during the charging/discharging process. For example, when the negative electrode active material layer 22 does not contain a binder, the negative electrode active material layer 22 may be easily separated from the negative electrode current collector 21. In a portion where the negative electrode current collector 21 is exposed due to the separation of the negative electrode active material layer 22 from the negative electrode current collector 21, a short circuit occurs when the negative electrode current collector 21 comes into contact with the solid electrolyte layer 30. The likelihood increases. The negative electrode active material layer 22 is produced by, for example, applying a slurry in which a material constituting the negative electrode active material layer 22 is dispersed on the negative electrode current collector 21 and drying it. By including the binder in the negative electrode active material layer 22, it is possible to stably disperse the negative electrode active material in the slurry. For example, when the slurry is applied on the negative electrode current collector 21 by a screen printing method, it is possible to suppress clogging of the screen (for example, clogging by an aggregate of negative electrode active materials).

The negative electrode active material layer 22 may further include additives used in the conventional all-solid secondary battery 1, such as a filler, a coating agent, a dispersant, an ion conductive auxiliary agent, and the like.

The thickness of the negative electrode active material layer 22 is, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or 5% or less of the thickness of the positive electrode active material layers 12, 12a, 12b. The thickness of the negative electrode active material layer 22 is, for example, 1um to 20um, 2um to 10um, or 3um to 7um. If the thickness of the negative electrode active material layer 22 is too thin, the lithium dendrite formed between the negative electrode active material layer 22 and the negative electrode current collector 21 collapses the negative electrode active material layer 22, resulting in an all-solid secondary battery (1). It is difficult to improve its cycle characteristics. When the thickness of the anode active material layer 22 is excessively increased, the energy density of the all-solid secondary battery 1 decreases and the internal resistance of the all-solid secondary battery 1 by the anode active material layer 22 increases. It is difficult to improve the cycle characteristics of (1).

When the thickness of the negative electrode active material layer 22 decreases, for example, the charging capacity of the negative electrode active material layer 22 decreases. The charging capacity of the anode active material layer 22 is, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, 5% or less, or 2% of the charging capacity of the cathode active material layer 12. Below. The charging capacity of the negative electrode active material layer 22 is, for example, 0.1% to 50%, 0.1% to 40%, 0.1% to 30%, 0.1% to 20%, 0.1% compared to the charging capacity of the positive electrode active material layer 12. To 10%, 0.1% to 5%, or 0.1% to 2%. If the charging capacity of the anode active material layer 22 is too small, the thickness of the anode active material layer 22 becomes very thin, so lithium formed between the anode active material layer 22 and the anode current collector 21 in repeated charging and discharging processes. It is difficult to improve the cycle characteristics of the all-solid secondary battery 1 by dendrite collapsing the negative electrode active material layer 22. When the charging capacity of the anode active material layer 22 is excessively increased, the energy density of the all-solid secondary battery 1 decreases, and the internal resistance of the all-solid secondary battery 1 by the anode active material layer 22 increases. It is difficult to improve the cycle characteristics of the battery 1.

The charging capacity of the positive electrode active material layer 12 is obtained by multiplying the charging capacity density (mAh/g) of the positive electrode active material by the mass of the positive electrode active material in the positive electrode active material layer 12. When several kinds of positive electrode active materials are used, a charge capacity density ㅧ mass value is calculated for each positive electrode active material, and the sum of these values is the charging capacity of the positive electrode active material layer 12. The charging capacity of the negative electrode active material layer 22 is also calculated in the same way. That is, the charging capacity of the anode active material layer 22 is obtained by multiplying the charging capacity density (mAh/g) of the anode active material by the mass of the anode active material in the anode active material layer 22. When several types of negative electrode active materials are used, a charge capacity density ㅧ mass value is calculated for each negative electrode active material, and the sum of these values is the capacity of the negative electrode active material layer 22. Here, the charging capacity density of the positive electrode active material and the negative electrode active material is an estimated capacity using an all-solid half-cell using lithium metal as a counter electrode. The charging capacity of the positive electrode active material layer 12 and the negative electrode active material layer 22 is directly measured by measuring the charging capacity using an all-solid half-cell. When the measured charging capacity is divided by the mass of each active material, the charging capacity density is obtained. Alternatively, the charging capacity of the positive electrode active material layer 12 and the negative electrode active material layer 22 may be an initial charging capacity measured at the time of charging the first cycle.

Referring to FIG. 6, the all-solid secondary battery 1a may further include, for example, a metal layer 23 disposed between the negative electrode current collector 21 and the negative electrode active material layer 22. The metal layer 23 contains lithium or a lithium alloy. Thus, the metal layer 23 acts as a lithium reservoir, for example. Lithium alloys are, for example, Li-Al alloys, Li-Sn alloys, Li-In alloys, Li-Ag alloys, Li-Au alloys, Li-Zn alloys, Li-Ge alloys, Li-Si alloys, etc. It is not limited to, and any one used as a lithium alloy in the art may be used. The metal layer 23 may be made of one of these alloys or lithium, or made of several types of alloys.

The thickness of the metal layer 23 is not particularly limited, but is, for example, 1um to 1000um, 1um to 500um, 1um to 200um, 1um to 150um, 1um to 100um, or 1um to 50um. When the thickness of the metal layer 23 is too thin, it is difficult to perform the role of a lithium reservoir by the metal layer 23. If the thickness of the metal layer 23 is too thick, there is a possibility that the mass and volume of the all-solid secondary battery 1 increases, and the cycle characteristics rather deteriorate. The metal layer 23 may be, for example, a metal foil having a thickness in this range.

In the all-solid secondary battery 1a, the metal layer 23 is disposed between the negative electrode current collector 21 and the negative electrode active material layer 22, for example, before assembling the all-solid secondary battery 1, or the all-solid secondary battery 1 It is deposited between the negative electrode current collector 21 (21, 21a, 21b) and the negative electrode active material layer 22 by charging after assembling of the negative electrode. When the metal layer 23 is disposed between the anode current collector 21 and the anode active material layer 22 before assembling the all-solid secondary battery 1a, the metal layer 23 is a metal layer containing lithium, so a lithium reservoir Acts as For example, a lithium foil is disposed between the negative electrode current collector 21 and the negative electrode active material layer 22 before assembling the all-solid secondary battery 1a. As a result, the cycle characteristics of the all-solid secondary battery 1a including the metal layer 23 are further improved. When the metal layer 23 is precipitated by charging after assembling the all-solid secondary battery 1a, the energy of the all-solid secondary battery 1a is not included when the all-solid secondary battery 1a is assembled. Density increases. For example, when the all-solid secondary battery 1 is charged, it is charged in excess of the charging capacity of the negative electrode active material layer 22. That is, the negative active material layer 22 is overcharged. At the initial stage of charging, lithium is occluded in the negative electrode active material layer 22. The negative electrode active material included in the negative electrode active material layer 22 forms an alloy or compound with lithium ions transferred from the positive electrode layer 10. When charging in excess of the capacity of the negative electrode active material layer 22, for example, lithium is deposited on the rear surface of the negative electrode active material layer 22, that is, between the negative electrode current collector 21 and the negative electrode active material layer 22. A metal layer corresponding to the metal layer 23 is formed by lithium. The metal layer 23 is a metal layer mainly composed of lithium (ie, metallic lithium). This result is obtained, for example, when the negative electrode active material included in the negative electrode active material layer 22 is made of a material that forms an alloy or compound with lithium. During discharge, the anode active material layer 22 and the metal layer 23, that is, lithium in the metal layer is ionized and moves toward the anode layer 10. Therefore, it is possible to use lithium as a negative electrode active material in the all-solid secondary battery 1a. In addition, since the negative electrode active material layer 22 covers the metal layer 23, it serves as the metal layer 23, that is, a protective layer for the metal layer, and at the same time serves to suppress the precipitation growth of lithium dendrites. Accordingly, short-circuiting and capacity reduction of the all-solid secondary battery 1a is suppressed, and as a result, the cycle characteristics of the all-solid secondary battery 1a are improved. In addition, when the metal layer 23 is disposed by charging after assembling the all-solid secondary battery 1a, the negative electrode current collector 21 and the negative electrode active material layer 22 and the region between them are, for example, all-solid secondary batteries. It is a Li-free region that does not contain lithium (Li) in the initial state of (1a) or in the state after discharge.

The negative electrode current collector 21 is made of, for example, a material that does not react with lithium, that is, does not form both an alloy and a compound. Materials constituting the negative electrode current collector 21 are, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), and the like, but is not necessarily limited thereto. Anything that is used as an electrode current collector in the technical field is possible. The negative electrode current collector 21 may be composed of one of the above-described metals, or may be composed of an alloy or a covering material of two or more metals. The negative electrode current collector 21 has a plate shape or a foil shape, for example.

The all-solid secondary battery 1 may further include, for example, a thin film including an element capable of forming an alloy with lithium on the negative electrode current collector 21. The thin film is disposed between the negative electrode current collector 21 and the negative electrode active material layer 22. The thin film contains, for example, an element capable of forming an alloy with lithium. An element capable of forming an alloy with lithium is, for example, gold, silver, zinc, tin, indium, silicon, aluminum, bismuth, etc., but is not necessarily limited thereto, and can form an alloy with lithium in the art. Any element is possible. The thin film is composed of one of these metals or an alloy of several types of metals. As the thin film is disposed on the anode current collector 21, for example, the deposition pattern of the metal layer 23 deposited between the thin film 24 and the anode active material layer 22 is further flattened, and the all-solid secondary battery 1 ) Can be further improved.

The thickness of the thin film is, for example, 1 nm to 800 nm, 10 nm to 700 nm, 50 nm to 600 nm, or 100 nm to 500 nm. When the thickness of the thin film is less than 1 nm, it may be difficult to exhibit the function of the thin film. If the thickness of the thin film is too thick, the thin film itself occludes lithium, thereby reducing the amount of lithium precipitated at the negative electrode, thereby lowering the energy density of the all-solid-state battery, and deteriorating the cycle characteristics of the all-solid-state secondary battery 1. The thin film may be disposed on the negative electrode current collectors 21, 21a, 21b by, for example, a vacuum evaporation method, sputtering method, plating method, etc., but is not necessarily limited to this method, and any method capable of forming a thin film in the art. It is possible.

A compound containing lithium of the solid ion conductor compound according to another embodiment; A compound containing an element selected from groups 2 and 11 of the periodic table; Compounds containing phosphorus (P); Compounds containing sulfur (S); And a compound containing a Group 17 element; contacting to provide a mixture; And heat-treating the mixture in an inert atmosphere to provide a solid ion conductor compound. The solid ion conductor compound is, for example, a solid ion conductor compound represented by Formula 1.

Compounds containing lithium include sulfides containing lithium. Lithium sulfide is mentioned, for example.

The compound containing an element selected from groups 2 and 11 of the periodic table includes sulfides containing an element selected from groups 2 and 11 of the periodic table. For example, copper sulfide, silver sulfide, sodium sulfide are mentioned.

The compound containing phosphorus (P) contains a sulfide containing phosphorus. For example, P ₂ S ₅ is mentioned.

The compound containing a group 17 element includes a lithium salt containing a group 17 element. For example, LiCl, LiF, LiBr, LiI are mentioned.

Such compounds can be prepared by contacting the starting material in an appropriate amount, for example a stoichiometric amount, to form a mixture, and heat treatment of the mixture. Contacting may include milling or grinding, such as, for example, ball milling.

The mixture may further include a compound containing a Group 1 metal element other than Li. The compound containing a Group 1 metal other than Li includes, for example, a sulfide of a Group 1 metal other than Li. For example, Na ₂ S, K ₂ S are mentioned.

A mixture of precursors mixed in a stoichiometric composition may be heat-treated in an inert atmosphere to prepare a solid ion conductor compound.

Heat treatment is, for example, 400 to 700 ℃, 400 To 650°C, 400 To 600° C., 400 To 550°C, or 400 to 500°C. The heat treatment time may be, for example, 1 to 36 hours, 2 to 30 hours, 4 to 24 hours, 10 to 24 hours, or 16 to 24 hours. The inert atmosphere is an atmosphere containing an inert gas. The inert gas is, for example, nitrogen, argon, or the like, but is not necessarily limited thereto, and any inert gas used in the art may be used.

The inventive idea will be described in more detail through the following examples and comparative examples. However, the examples are for illustrative purposes only and are not intended to limit the scope of the creative ideas.

(Preparation of solid ion conductor compound)

Example 1: (Li _5.72 Cu _0.03 )PS _4.75 Cl _1.25 Manufacture of

In a glove box in an Ar atmosphere, the target composition of Li ₂ S _{as a lithium precursor, P 2} S _{5 as a} phosphorus precursor, LiCl as a chlorine precursor, and Cu ₂ S as a _{copper precursor (Li 5.72} Cu _0.03 ) PS _4.75 Cl _{After combining at a stoichiometric ratio to obtain 1.25} , pulverizing and mixing at 100 rpm for 1 hour in an Ar atmosphere planetary ball mill containing zirconia (YSZ) balls, followed by 30 minutes at 800 rpm During pulverization and mixing to obtain a mixture. The obtained mixture was pressed under uniaxial pressure to prepare pellets having a thickness of about 10 mm and a diameter of about 13 mm. The prepared pellets were covered with gold foil and then placed in a carbon crucible, and the carbon crucible was vacuum-sealed using a quartz glass tube. The vacuum-sealed pellet was heated from room temperature to 500°C at 1.0°C/min using an electric furnace, heat-treated at 500°C for 12 hours, and then cooled to room temperature at 1.0°C/min to prepare a solid ion conductor compound. The composition of the prepared solid ion conductor compound was (Li _5.72 Cu _0.03 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.005).

Example 2: (Li _5.69 Cu _0.06 )PS _4.75 Cl _1.25 Manufacture of

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition (Li _5.69 Cu _0.06 ) PS _4.75 Cl _1.25.

The composition of the prepared solid ion conductor compound was (Li _5.69 Cu _0.06 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.01).

Example 3: (Li _5.63 Cu _0.12 )PS _4.75 Cl _1.25 Manufacture of

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition, (Li _5.63 Cu _0.12 ) PS _4.75 Cl _1.25.

The composition of the prepared solid ion conductor compound was (Li _5.63 Cu _0.12 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.02).

Example 4: (Li _5.57 Cu _0.18 )PS _4.75 Cl _1.25 Manufacture of

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition (Li _5.57 Cu _0.18 ) PS _4.75 Cl _1.25.

The composition of the prepared solid ion conductor compound was (Li _5.57 Cu _0.18 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.03).

Example 5: (Li _5.45 Cu _0.3 )PS _4.75 Cl _1.25 Manufacture of

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition (Li _5.45 Cu _0.3 ) PS _4.75 Cl _1.25.

The composition of the prepared solid ion conductor compound was (Li _5.45 Cu _0.3 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.05).

Example 6: (Li _5.15 Cu _0.6 )PS _4.75 Cl _1.25 Manufacture of

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition (Li _5.15 Cu _0.6 ) PS _4.75 Cl _1.25.

The composition of the prepared solid ion conductor compound was (Li _5.15 Cu _0.6 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.10).

Example 7: (Li _5.72 Ag _0.03 )PS _4.75 Cl _1.25 Produce

The same method as in Example 1 except that the stoichiometric mixing ratio of the starting material was changed by using _{Ag precursor Ag 2} S instead of Cu precursor so that the desired composition (Li _5.72 Ag _0.03 ) PS _4.75 Cl _{1.25 was obtained.} To prepare a solid ion conductor compound. The composition of the prepared solid ion conductor compound was (Li _5.72 Ag _0.03 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.005).

Example 8: (Li _5.72 Cu _0.02 Na _0.01 )PS _4.75 Cl _1.25 Produce

The purpose of the composition of _{(Li 5.72 Cu 0.02 Na 0.01)} PS 4.75 Cl 1.25 that is obtained and is carried out except for changing the stoichiometric ratio of the starting materials using a Cu precursor, Cu ₂ S and Na precursor of Na ₂ S A solid ion conductor compound was prepared in the same manner as in Example 1. The composition of the prepared solid ion conductor compound was (Li _5.72 Cu _0.02 Na _0.01 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.005).

Example 9: (Li _5.74 Cu _0.01 )PS _4.75 Cl _1.25 Produce

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition (Li _5.72 Cu _0.01 ) PS _4.75 Cl _1.25. The composition of the prepared solid ion conductor compound was (Li _5.74 Cu _0.01 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.0017).

Example 10: (Li _5.70 Cu _0.05 )PS _4.75 Cl _1.25 Produce

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition, (Li _5.70 Cu _0.05 ) PS _4.75 Cl _1.25. The composition of the prepared solid ion conductor compound was (Li _5.70 Cug _0.05 ) PS _4.75 Cl _1.25 (substituted cation ratio: 0.0088).

Example 11: (Li _5.72 Cu _0.03 )PS _4.75 Cl _1.15 Br _0.1 Produce

A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition, (Li _5.72 Cu _0.03 ) PS _4.75 Cl _1.15 Br _0.1. The composition of the prepared solid ion conductor compound was (Li _5.72 Cu _0.03 ) PS _4.75 Cl _1.15 Br _0.1 (substituted cation ratio: 0.005). LiBr was additionally used as a bromine precursor.

Example 12: (Li _5.72 Cu _0.03 )P(S _4.725 (SO ₄ ) _0.025 )Cl _1.25 Produce

A solid ion conductor compound in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition, (Li _5.72 Cu _0.03 )P(S _4.725 (SO ₄ ) _0.025 )Cl _1.25. Was prepared. The composition of the prepared solid ion conductor compound was (Li _5.72 Cu _0.03 )P(S _4.725 (SO ₄ ) _0.025 )Cl _1.25 (substituted cation (Cu) ratio: 0.005, substituted anion (SO ₄ ) ratio: 0.005) . As the SO ₄ precursor, Li ₂ SO ₄ was additionally used.

Comparative Example 1: Li _5.75 PS _4.75 Cl _1.25 Manufacture of

A solid ion conductor compound was prepared in the same manner as in Example 1, except that a Cu precursor was not added and the stoichiometric mixing ratio of the starting material was changed to obtain the desired composition of Li _5.75 PS _4.75 Cl _1.25. The composition of the prepared solid ion conductor compound was Li _5.75 PS _4.75 Cl _1.25 .

Example 13: Manufacture of all-solid secondary battery

(Anode layer manufacturing)

_{LiNi 0.8} Co _0.15 Al _0.05 O ₂ (NCA) was prepared as a positive electrode active material. As a solid electrolyte, a sulfide-based solid electrolyte powder prepared in Example 1 was prepared. Carbon nanofibers (CNF) were prepared as a conductive agent. A positive electrode mixture was prepared by mixing these materials in a weight ratio of positive electrode active material: solid electrolyte: conductive agent = 60:35:5.

(Preparation of solid electrolyte powder)

The sulfide-based solid ion conductor compound prepared in Example 1 was pulverized using an agate mortar and used as a solid electrolyte powder.

(Manufacture of cathode layer)

A metal lithium foil having a thickness of 30 um was prepared as a negative electrode.

(Manufacture of all-solid secondary battery)

After sequentially stacking a 30 μm thick lithium metal foil, 150 mg of solid electrolyte powder, and 15 mg of a positive electrode mixture on the SUS lower electrode, a SUS upper electrode was placed on the positive electrode mixture to prepare a laminate, and then 4 ton/ton of the prepared laminate. It was pressed for 2 minutes at a pressure of ^{cm 2.} Then, an all-solid secondary battery was prepared by pressing the pressed laminate with a torque of 4 N·m using a torque wrench.

In the manufactured all-solid secondary battery, the solid electrolyte was not decomposed by the lithium metal anode and was stable.

Examples 14 to 24

An all-solid secondary battery was manufactured in the same manner as in Example 13, except that the solid electrolyte powder prepared in Examples 2 to 12 was used instead of the solid electrolyte powder prepared in Example 1.

Comparative Example 2

An all-solid secondary battery was manufactured in the same manner as in Example 13, except that the solid electrolyte powder prepared in Comparative Example 1 was used instead of the solid electrolyte powder prepared in Example 1.

Evaluation Example 1: X-ray diffraction experiment

After preparing a powder by pulverizing the solid ion conductor compounds prepared in Examples 1 to 5 using an agate mortar, the powder XRD spectrum was measured, and a part of the result is shown in FIG. 1. Cu Kα radiation was used to measure the XRD spectrum. The solid ion conductor compounds of Examples 1 to 5 belong to the F-23m space group, have a structure belonging to the cubic crystal system, and have an azirodite type crystal structure. sulfide).

The solid ion conductor compound of Example 2 is the peak intensity (Ib) at the diffraction angle 2θ = 53.0 ° ± 1.0 ° to the peak intensity (Ia) at the diffraction angle 2θ = 46.0 ° ± 1.0 ° in the XRD spectrum using a CuKα ray The peak intensity ratio Ia/Ib of was 0.79.

The solid ion conductor compound of Example 3 is the peak intensity (Ib) at the diffraction angle 2θ = 53.0°±1.0° to the peak intensity (Ia) at the diffraction angle 2θ = 46.0°±1.0° in the XRD spectrum using CuKα rays. The peak intensity ratio Ia/Ib of was 0.90.

The solid ion conductor compound of Example 2 had a half width (FWHM) of about 0.2° at diffraction angle 2θ = 46.0°±1.0° in the XRD spectrum using CuKα rays.

The solid ion conductor compound of Example 3 had a half width (FWHM) of about 0.2° at diffraction angle 2θ=46.0°±1.0° in the XRD spectrum using CuKα rays.

Evaluation Example 2: Measurement of ion conductivity

After preparing a powder by pulverizing the solid ion conductor compounds prepared in Examples 1 to 12 and Comparative Example 1 using an agate mortar, 200 mg of the powder was pressed for 2 minutes at a pressure of ^{4 ton/cm 2 to have a thickness of about} A pellet specimen of 0.101 mm and a diameter of about 13 mm was prepared. Symmetry cells were prepared by placing indium (In) electrodes having a thickness of 50 μm and a diameter of 13 mm on both sides of the prepared specimen. The preparation of the symmetric cell was carried out in a gloverbox in an Ar atmosphere.

The impedance of the pellets was measured by a 2-probe method using an impedance analyzer (Material Mates 7260 impedance analyzer) with respect to the specimen in which indium electrodes were disposed on both sides. The frequency range was 0.1 Hz to 1 MHz, and the amplitude voltage was 10 mV. It was measured at 25°C in an Ar atmosphere. The resistance value was calculated from the arc of the Nyguist plot for the impedance measurement result, and the ion conductivity was calculated by considering the area and thickness of the specimen.

The measurement results are shown in Table 1 and FIG. 2 below.

Room temperature (25℃) ion conductivity
[mS/cm] Example 1 3.8 Example 2 3.4 Example 3 3.7 Example 4 3.2 Example 5 2.7 Example 6 1.8 Example 7 3.28 Example 8 4.03 Example 9 3.48 Example 10 3,73 Example 11 4.3 Example 12 2.8 Comparative Example 1 2.2

As shown in Tables 1 and 2, the solid ion conductor compounds of Examples 1 to 12 exhibited high ionic conductivity of 1.8 mS/cm or more at room temperature.

The solid ion conductor compounds of Examples 1 to 5 and Examples 7 to 12 showed improved ionic conductivity compared to the solid ion conductor compound of Comparative Example 1.

Evaluation Example 3: Atmospheric stability evaluation

After preparing powder by pulverizing the solid ion conductor compound prepared in Example 3 and Comparative Example 1 using an agate mortar, the prepared powder was dried in an air atmosphere having a dew point of less than -60°C. After 10 days storage in a dry room, they were taken out and the change in ionic conductivity was measured. The change in ionic conductivity was calculated using the ionic conductivity retention rate of Equation 1 below. The measurement results are shown in Table 2 below. The initial ionic conductivity is the ionic conductivity of the prepared powder before storage in the dry room. The ion conductivity was measured under the same conditions in the same manner as in Evaluation Example 2.

<Equation 1>

Ion conductivity retention rate = [Ion conductivity of the solid ion conductor compound after 10 days / Ion conductivity of the initial solid ion conductor compound] × 100

Ion conductivity retention rate [%] Example 3 77.4 Comparative Example 1 65.6

As shown in Table 1, the solid ion conductor compound of Example 3 exhibited improved ionic conductivity retention compared to the solid ion conductor compound of Comparative Example 1.

The solid ion conductor compound of Example 3 showed improved atmospheric stability compared to the solid ion conductor compound of Comparative Example 1.

Evaluation Example 4: Charge/discharge test, evaluation of interfacial stability

The charge and discharge characteristics of the all-solid secondary batteries prepared in Example 13 and Comparative Example 2 were evaluated by the following charge and discharge tests. The charging/discharging test was performed by putting an all-solid secondary battery in a chamber at 45°C.

The first cycle was charged with a constant current of 0.1C and a constant voltage of 4.25V until the battery voltage reached 4.25V until the current value reached 0.05C. Subsequently, discharge was performed at a constant current of 0.1 C until the battery voltage became 2.5 V. The discharge capacity of the first cycle was taken as the standard capacity.

The second cycle was charged with a constant current of 0.1C and a constant voltage of 4.25V for 40 hours until the battery voltage became 4.25V. Subsequently, discharge was performed at a constant current of 0.1 C until the battery voltage became 2.5 V. The discharge capacity of the second cycle was taken as the retention capacity.

The third cycle was charged with a constant current of 0.1C and a constant voltage of 4.25V for 40 hours until the battery voltage became 4.25V. Subsequently, discharge was performed at a constant current of 0.1 C until the battery voltage became 2.5 V. The discharge capacity of the third cycle was taken as the recovery capacity.

After each cycle, the charging and discharging steps were allowed to rest for 10 minutes.

The capacity recovery rate after high temperature storage and the capacity retention rate after high temperature storage of the all-solid secondary batteries prepared in Example 13 and Comparative Example 2 are shown in Table 3 below.

The capacity retention rate after high temperature storage and the capacity recovery rate after high temperature storage are calculated from Equations 2 and 3 below.

<Equation 2>

Holding capacity ratio (%) = [Maintenance capacity / standard capacity]×100

<Equation 3>

Recovery capacity ratio (%) = [Recovery capacity / standard capacity]×100

Maintenance capacity ratio [%] Recovery capacity rate [%] Example 13 100 97.7 Comparative Example 2 98.8 96.4

As shown in Table 3, compared to the all-solid secondary battery of Comparative Example 2, the all-solid secondary battery of Example 13 exhibited improved storage capacity ratio and recovery capacity ratio after being left in a charged state at high temperature for a long time.

The all-solid secondary battery of Example 11 showed improved stability (eg, oxidation resistance) to lithium metal compared to the all-solid secondary battery of Comparative Example 2.

Evaluation Example 5: Charging/discharging test, evaluation of life characteristics

Life characteristics of the all-solid secondary batteries of Example 13 and Comparative Example 2 in which the oxidation stability evaluation of Evaluation Example 4 was completed were evaluated. The charge/discharge test was performed by putting an all-solid secondary battery in a chamber at 45°C.

The battery was charged at a constant current of 0.1 C until the voltage reached 4.25 V, and charged at a constant voltage of 4.25 V until the current value became 0.05 C. Subsequently, discharge was performed at a constant current of 0.1 C until the battery voltage became 2.5 V. This charge/discharge cycle was performed 10 times. After each cycle, the charging and discharging steps were allowed to rest for 10 minutes. The capacity retention rates of the all-solid secondary batteries prepared in Example 13 and Comparative Example 2 are shown in Tables 4 and 3 below. The capacity retention rate is calculated from Equation 4 below.

<Equation 4>

Capacity retention rate (%) = [Discharge capacity of the 10th cycle / Discharge capacity of the first cycle] × 100

Capacity retention rate [%] Example 13 97.7 Comparative Example 2 95

As shown in Tables 4 and 3, the all-solid secondary battery of Example 13 has improved oxidation resistance and interfacial stability compared to the all-solid secondary battery of Comparative Example 2, thereby improving high-temperature life characteristics.

Claims (34)

A solid ion conductor compound represented by the following Chemical Formula 1 and having an Argyrodite type crystal structure:
<Formula 1>
Li _a M1 _x M2 _w PS _y M3 _z
In the above formula,
M1 is one or more elements selected from groups 2 and 11 of the periodic table,
M2 is one or more metal elements other than Li selected from Group 1 of the periodic table,
M3 is one or more elements selected from group 17 of the periodic table,
4≤a≤8, 0<x<0.5, 0≤w<0.5, 3≤y≤7, and 0≤z≤2. The solid ion conductor compound according to claim 1, wherein M1 comprises Cu, Ag, Mg, or a combination thereof. The solid ion conductor compound according to claim 1, wherein M2 comprises Na, K, or a combination thereof. The solid ion conductor compound according to claim 1, wherein M3 comprises F, Cl, Br, I, or a combination thereof. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 2:
<Formula 2>
Li _7-xz M1 _x PS _6-z M3 _z
In the above formula,
M1 is at least one element selected from groups 2 and 11 of the periodic table, and is a monovalent cation,
M3 is one or more elements selected from group 17 of the periodic table, -1 is an anion,
0<x<0.5 and 0≤z≤2. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 2a:
<Formula 2a>
Li _7-xz M1 _x PS _6-z Cl _z
In the above formula,
M1 is Mg, Ag, Cu, or a combination thereof,
0<x<0.5 and 1≦z≦2. The solid ion conductor compound of claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 2b:
<Formula 2b>
Li _5.75-x M1 _x PS _4.75 Cl _1.25
In the above formula,
M1 is Mg, Ag, Cu, or a combination thereof,
0<x<0.05. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 3:
<Formula 3>
(Li _1-b M1 _b ) _7-z PS _6-z M3 _z
In the above formula,
M1 is at least one element selected from groups 2 and 11 of the periodic table, and is a monovalent cation,
M3 is one or more elements selected from group 17 of the periodic table, -1 is an anion,
0<b≤0.06 and 0≤z≤2. The solid ion conductor compound of claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formulas 3a to 3c:
<Formula 3a>
(Li _1-b Cu _b ) _7-z PS _6-z M3 _z
<Formula 3b>
(Li _1-b Ag _b ) _7-z PS _6-z M3 _z
<Formula 3c>
(Li _1-b Mg _b ) _7-z PS _6-z M3 _z
In the above equations,
M3 is F, Cl, Br, I or a combination thereof,
0<b≤0.06 and 0≤z≤2. The solid ion conductor compound according to claim 8, wherein 0<b<0.05. The solid ion conductor compound of claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following formulas:
(Li _1-b Cu _b ) _7-z PS _6-z Cl _z , (Li _1-b Ag _b ) _7-z PS _6-z Cl _z , (Li _1-b Mg _b ) _7-z PS _{6- z} Cl _z , (Li _1-b Cu _b ) _7-z PS _6-z Br _z , (Li _1-b Ag _b ) _7-z PS _6-z Br _z , (Li _1-b Mg _b ) _{7- z} PS _6-z Br _z , (Li _1-b Cu _b ) _7-z PS _6-z I _z , (Li _1-b Ag _b ) _7-z PS _6-z I _z , (Li _1-b Mg _b ) _7-z PS _6-z I _z
In the above equations, 0<b≤0.05 and 0<z≤2. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 4:
<Formula 4>
Li _7-xwz M1 _x M2 _w PS _6-z M3 _z
In the above formula,
M1 is at least one element selected from groups 2 and 11 of the periodic table, and is a monovalent cation,
M2 is one or more metal elements other than Li selected from Group 1 of the periodic table, and is a monovalent cation,
M3 is one or more elements selected from group 17 of the periodic table, -1 is an anion,
0<x<0.5, 0≦w<0.5, 0<x+w<0.5, and 0≦z≦2. The solid ion conductor compound of claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 4a:
<Formula 4a>
Li _7-xwz M1 _x M2 _w PS _6-z Cl _z
In the above formula,
M1 is Mg, Ag, Cu or a combination thereof,
M2 is Na, K or a combination thereof,
0<x<0.5, 0<w<0.5, 0<x+w<0.5, and 1≦z≦2. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 4b:
<Formula 4b>
Li _5.75-xw M1 _x M2 _w PS _4.75 Cl _1.25
In the above formula,
M1 is Mg, Ag, Cu or a combination thereof,
M2 is Na, K or a combination thereof,
0<x<0.05, 0<w<0.05, 0<x+w<0.05. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formula 5:
<Formula 5>
(Li _1-bc M1 _b M2 _c ) _7-z PS _6-z M3 _z
In the above formula,
M1 is at least one element selected from groups 2 and 11 of the periodic table, and is a monovalent cation,
M2 is one or more metal elements other than Li selected from Group 1 of the periodic table, and is a monovalent cation,
M3 is one or more elements selected from group 17 of the periodic table, -1 is an anion,
0<b<0.1, 0<c<0.1, 0<b+c≤0.1, and 0≤z≤2. The solid ion conductor compound of claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following Formulas 5a to 5f:
<Formula 5a>
(Li _1-bc Cu _b Na _c ) _7-z PS _6-z M3 _z
<Formula 5b>
(Li _1-bc Ag _b Na _c ) _7-z PS _6-z M3 _z
<Formula 5c>
(Li _1-bc Mg _b Na _c ) _7-z PS _6-z M3 _z
<Formula 5d>
(Li _1-bc Cu _b K _c ) _7-z PS _6-z M3 _z
<Formula 5e>
(Li _1-bc Ag _b K _c ) _7-z PS _6-z M3 _z
<Formula 5f>
(Li _1-bc Mg _b K _c ) _7-z PS _6-z M3 _z
In the above equations,
M3 is ^{F -, Cl -, Br -} , I - or a combination thereof,
0<b<0.1, 0<b<0.1, 0<b+c≤0.1, and 0≤z≤2. The solid ion conductor compound of claim 1, wherein the solid ion conductor compound represented by Formula 1 is represented by the following formulas:
(Li _1-bc Cu _b Na _c ) _7-z PS _6-z Cl _z , (Li _1-bc Ag _b Na _c ) _7-z PS _6-z Cl _z , (Li _1-bc Mg _b Na _c ) _7-z PS _6-z Cl _z , (Li _1-bc Cu _b K _c ) _7-z PS _6-z Cl _z , (Li _1-bc Ag _b K _c ) _7-z PS _6-z Cl _z , (Li _1-bc Mg _b K _c ) _7-z PS _6-z Cl _z , (Li _1-bc Cu _b Na _c ) _7-z PS _6-z Br _z , (Li _1-bc Ag _b Na _c ) _7-z PS _6-z Br _z , (Li _1-bc Mg _b Na _c ) _7-z PS _6-z Br _z , (Li _1-bc Cu _b K _c ) _7-z PS _6-z Br _z , (Li _1-bc Ag _b K _c ) _7-z PS _6-z Br _z , (Li _1-bc Mg _b K _c ) _7-z PS _6-z Br _z , (Li _1-bc Cu _b Na _c ) _7-z PS _6-z I _z , (Li _1-bc Ag _b Na _c ) _7-z PS _6-z I _z , (Li _1-bc Mg _b Na _c ) _7-z PS _6-z I _z , (Li _1-bc Cu _b K _c ) _7-z PS _6-z I _z , (Li _1-bc Ag _b K _c ) _7-z PS _6-z I _z , (Li _1-bc Mg _b K _c ) _7-z PS _6-z I _z
In the above equations, 0<b<0.05, 0<c<0.05, 0<b+c≤0.05, and 0<z≤2. The solid ion conductor compound according to claim 1, wherein a part of S in the solid ion conductor compound represented by Formula 1 is additionally substituted _{with SO 4.} The solid ion conductor compound according to claim 18, wherein _{the solid ion conductor compound in which a part of S is further substituted with SO 4} is represented by the following formula (6).
<Formula 6>
Li _a M1 _x M2 _w PS _yp (SO ₄ ) _p M3 _z
In the above formula,
M1 is one or more elements selected from groups 2 and 11 of the periodic table,
M2 is one or more metal elements other than Li selected from Group 1 of the periodic table,
M3 is one or more elements selected from group 17 of the periodic table,
4≤a≤8, 0<x<0.5, 0≤w<0.5, 3≤y≤7, 0<p<2, and 0≤z≤2. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 has an ion conductivity of 0.5 mS/cm or more at 25°C. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 has an ion conductivity of 1.0 mS/cm or more at 25°C. The method of claim 1, wherein the solid ion conductor compound represented by Formula 1 has an ionic conductivity retention of 70% or more after 10 days in a dry condition in an air atmosphere having a dew point of less than -60°C, and the ion The conductivity retention is represented by the following equation (1), a solid ion conductor compound.
<Equation 1>
Ion conductivity retention rate = [Ion conductivity of the solid ion conductor compound after 10 days / Ion conductivity of the initial solid ion conductor compound] × 100 The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 belongs to a cubic crystal system. The solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 belongs to the F-43m space group. The peak intensity of the peak intensity (Ib) at the diffraction angle 2θ=53.0°±1.0° for the peak intensity (Ia) at the diffraction angle 2θ=46.0°±1.0° in the XRD spectrum using a CuKα ray. A solid ion conductor compound having a ratio Ia/Ib of 1 or less. The solid ion conductor compound according to claim 1, wherein the half width (FWHM) of the peak at diffraction angle 2θ=46.0°±1.0° in the XRD spectrum using CuKα rays is 0.3° or less. A solid electrolyte comprising the solid ion conductor compound according to any one of claims 1 to 26. An anode layer including a cathode active material layer;
A negative electrode layer including a negative electrode active material layer; And
It includes an electrolyte layer disposed between the anode layer and the cathode layer,
An electrochemical cell in which the positive electrode active material layer and the electrolyte layer contain the solid ion conductor compound according to any one of claims 1 to 26. The electrochemical cell according to claim 28, wherein the electrochemical cell is an all-solid secondary battery. The method of claim 28, wherein the negative electrode active material layer comprises a negative electrode active material and a binder,
The negative electrode active material is amorphous carbon, gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn) And zinc (Zn) is a mixture with one or more selected from the group consisting of, electrochemical cell. The electrochemical cell of claim 28, further comprising a metal layer disposed between the negative electrode current collector and the negative electrode active material layer, wherein the metal layer comprises lithium or a lithium alloy. Compounds containing lithium; A compound containing an element selected from groups 2 and 11 of the periodic table; Compounds containing phosphorus (P); And optionally a compound containing a Group 17 element; contacting to provide a mixture; And
Heat-treating the mixture in an inert atmosphere to provide a solid ion conductor compound. 33. The method for producing a solid ion conductor compound according to claim 32, wherein the mixture further comprises a compound containing a Group 1 metal element other than Li. The method of claim 32, wherein the heat treatment is performed at a temperature of 400°C to 600°C for 1 to 36 hours.

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