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

Abstract

It is represented by the following chemical formula 1, and A solid ion-conducting compound having an azirodite-type crystal structure, a solid electrolyte containing the same, an electrochemical cell containing the same, and a method for manufacturing the same are presented: LixM1vPSyM2wM3z In the above formula, M1 is one or more metallic elements other than Li selected from groups 1 to 15 of the periodic table, M2 is SOn, M3 is an element selected from group 17 of the periodic table, and 4≤x≤8, 0≤v<1, 3≤y≤7, 0

Description

Technology Field

[0001] The invention relates to a solid ion-conducting compound, a solid electrolyte containing the same, a lithium battery containing the same, and a method for manufacturing the same. Background Technology

[0002] All-solid-state lithium batteries contain a solid electrolyte. Since all-solid-state lithium batteries do not contain flammable organic solvents, they offer excellent stability.

[0003] Conventional solid electrolyte materials are not sufficiently stable with respect to lithium metal. Furthermore, the lithium ion conductivity of conventional solid electrolytes is lower than that of liquid substitutes. The problem to be solved

[0004] One aspect is to provide a solid ion conductor compound with improved lithium ion conductivity, oxidation stability, and atmospheric stability by having a new composition.

[0005] Another aspect is to provide a solid electrolyte comprising the above-mentioned solid ion-conducting compound.

[0006] Another aspect is to provide an electrochemical cell comprising the above-mentioned solid ion conductor compound.

[0007] Another aspect is to provide a method for manufacturing the above-mentioned solid ion conductor. means of solving the problem

[0008] Depending on one aspect

[0009] It is represented by the following chemical formula 1, and

[0010] A solid ion conductor compound having an azirodite-type crystal structure is provided:

[0011] <Chemical Formula 1>

[0012] Li x M1 v PS y M2 w M3 z

[0013] In the above formula,

[0014] M1 is one or more metallic elements other than Li selected from groups 1 to 15 of the periodic table, and

[0015] M2 is SO n is,

[0016] M3 is an element selected from Group 17 of the periodic table, and

[0017] 4≤x≤8, 0≤v<1, 3≤y≤7, 0 <w<2, 0≤z≤2, 및 1.5≤n≤5이다.

[0018] Depending on the other aspect

[0019] A solid electrolyte comprising a solid ion-conducting compound according to the above is provided.

[0020] According to another aspect

[0021] Anode layer including an anode active material layer;

[0022] A cathode layer comprising a cathode active material layer; and

[0023] It includes an electrolyte layer disposed between the anode layer and the cathode layer, and

[0024] An electrochemical cell is provided in which the positive active material layer and the electrolyte layer comprise a solid ion conductor compound according to the above.

[0025] According to another aspect

[0026] A compound containing lithium; one or more compounds containing a metal element other than Li selected from Groups 1 to 15 of the periodic table; a compound containing phosphorus (P); SO n A step of providing a mixture by contacting a compound comprising (1.5≤n≤5); and optionally a compound comprising an element of Group 17 of the periodic table; and

[0027] A method for preparing a solid ion conductor compound is provided, comprising the step of heat-treating the above mixture in an inert atmosphere to provide a solid ion conductor compound. Effects of the invention

[0028] According to one aspect, an electrochemical cell having improved stability and cycle characteristics is provided by including a solid ion conductor compound with improved lithium ion conductivity and stability with respect to lithium metal. Brief explanation of the drawing

[0029] Figure 1a is the powder XRD spectrum for the solid ion conductor compounds prepared in Examples 1 to 3 and Reference Example 1. Figure 1b is a partial enlarged view of Figure 1a. Fig. 1c is a partial enlarged view of Fig. 1b. FIG. 2 is a schematic diagram of one embodiment of an all-solid-state secondary battery. FIG. 3 is a schematic diagram of another embodiment of an all-solid-state secondary battery. FIG. 4 is a schematic diagram of another embodiment of an all-solid-state secondary battery. <Explanation of symbols for major parts of the drawing> 1, 1a: All-solid-state secondary battery 10: Cathode 11: Positive current collector 12: Positive active material layer 20: Cathode 21: Cathode current collector 22: Cathode active material layer 23: Metal layer 30: Solid electrolyte layer 40: All-solid-state secondary battery Specific details for implementing the invention

[0030] Various embodiments are illustrated in the accompanying drawings. However, the present creative concept may be embodied in many different forms and should not be interpreted as being limited to the embodiments described herein. Rather, these embodiments are provided to ensure that the present disclosure is thorough and complete and will sufficiently convey the scope of the present creative concept to those skilled in the art. Identical reference numerals denote identical components.

[0031] When it is stated that one component is "on top" of another component, it can be understood that it may be directly on top of the other component or that another component may be interposed between them. In contrast, when it is stated that a component is "directly on top" of another component, no component is interposed between them.

[0032] Terms such as "first," "second," "third," etc., may be used in this specification to describe various components, components, regions, layers, and / or zones, but these components, components, regions, layers, and / or zones should not be limited by these terms. These terms are used solely to distinguish one component, component, region, layer, or zone from another. Accordingly, the first component, component, region, layer, or zone described below may be referred to as the second component, component, region, layer, or zone without departing from the teachings of this specification.

[0033] The terms used herein are intended to describe specific embodiments only and are not intended to limit the creative idea. The singular form used herein is intended to include the plural form including "at least one" unless the content clearly indicates otherwise. "At least one" should not be interpreted as limiting to the singular. As used herein, the term "and / or" includes any combination of one or more of the listed items. The terms "comprising" and / or "comprising" as used in the detailed description specify the presence of the specified features, regions, integers, steps, actions, components, and / or components, and do not exclude the presence or addition of one or more other features, regions, integers, steps, actions, components, components, and / or groups thereof.

[0034] Spatially relative terms such as "bottom," "lower," "subordinate," "top," "upper," and "upper" may be used herein to facilitate the description of the relationship of one component or feature to another component or feature. Spatially relative terms are to be understood as intended to include different orientations of the device during use or operation in addition to the orientations depicted in the drawings. For example, if the device in the drawings is inverted, a component described as "bottom" or "lower" of another component or feature will be oriented to the "top" of that other component or feature. Thus, the exemplary term "bottom" may encompass both the upper and lower directions. The device may be positioned in different directions (it may be rotated 90 degrees or rotated in other directions), and spatially relative terms used herein may be interpreted accordingly.

[0035] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) have the same meaning as generally understood by those skilled in the art to which this disclosure pertains. Furthermore, it will also be understood that terms as defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning within the context of the relevant technology and the content of this disclosure, and should not be interpreted in an idealized or overly formal sense.

[0036] Exemplary embodiments are described herein with reference to cross-sectional views, which are schematic diagrams of idealized embodiments. As such, variations from the depicted shapes should be expected as a result of, for example, manufacturing techniques and / or tolerances. Accordingly, the embodiments described herein should not be interpreted as being limited to the specific shapes of the regions as depicted herein, but should include variations in shapes resulting from, for example, manufacturing. For example, a region depicted or described as flat may typically have rough and / or non-linear features. Furthermore, an angle depicted as sharp may be rounded. Accordingly, the regions depicted in the drawings are essentially schematic, and the shapes are not intended to depict the exact shape of the region and are not intended to limit the scope of the claims.

[0037] "Group" refers to a group of elements in the periodic table according to the International Union of Pure and Applied Chemistry ("IUPAC") group classification system of groups 1-18.

[0038] Although specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not currently anticipated or cannot be anticipated may arise to the applicant or those skilled in the art. Accordingly, the appended claims, which may be filed and modified, are intended to include all such alternatives, modifications, variations, improvements, and substantial equivalents.

[0039] A solid ion-conducting compound according to one or more exemplary embodiments, a solid electrolyte containing the same, an electrochemical cell containing the same, and a method for manufacturing the solid ion-conducting compound are described in more detail below.

[0040] [Solid Ion Conductor Compounds]

[0041] A solid ion conductor compound according to one embodiment is represented by the following chemical formula 1 and has an azyrodite-type crystal structure:

[0042] <Chemical Formula 1>

[0043] Li x M1 v PS y M2 w M3 z

[0044] In the above formula, M1 is one or more metallic elements other than Li selected from groups 1 to 15 of the periodic table, and M2 is SO n And, M3 is an element selected from Group 17 of the periodic table, where 4≤x≤8, 0≤v<1, 3≤y≤7, 0 <w<2, 0≤z≤2, 및 1.5≤n≤5이다. 예를 들어, 5≤x≤8, 0≤v<1, 4≤y≤7, 0<w<2, 0≤z≤2, 및 1.5≤n≤5이다. 예를 들어, 5≤x≤7, 0≤v<1, 4≤y≤6, 0<w<2, 0≤z≤2, 및 1.5≤n≤5이다. 예를 들어, 5.4≤x≤7, 0≤v<1, 4.5≤y≤6, 0<w<2, 0.2≤z≤1.8, 및 1.5≤n≤5이다.

[0045] The compound represented by Chemical Formula 1 is a crystalline compound having an azyrodite-type crystal structure, and by including SO4 substituted in some of the sulfur (S) sites within the crystal structure, the ionic conductivity of lithium ions within the compound can be enhanced and the activation energy can be reduced. For example, the crystal lattice volume can be increased by placing other ions with a larger ionic radius than the sulfur ion in some of the sulfur (S) sites contained in the solid ion conductor compound represented by Chemical Formula 1. As the crystal lattice volume increases, the movement of lithium ions within the crystal lattice can be facilitated. Additionally, the structural stability of the compound can be enhanced by placing SO4 containing oxygen atoms, which have superior oxidation stability and / or atmospheric stability compared to sulfur atoms, in some of the sulfur (S) sites contained in the solid ion conductor compound represented by Chemical Formula 1.

[0046] In addition, the compound represented by Chemical Formula 1 may have its ionic conductivity of lithium ions enhanced and its activation energy reduced by including M and / or Me substituted in parts of the lithium sites within the crystal structure. For example, the crystal lattice volume may be increased by placing other ions with the same oxidation number as lithium and ionic radii similar to or larger than those of lithium ions in parts of the lithium sites contained in the solid ion conductor compound represented by Chemical Formula 1. The increase in crystal lattice volume may facilitate the movement of lithium ions within the crystal lattice. Furthermore, for example, parts of the lithium sites contained in the solid ion conductor compound represented by Chemical Formula 1 may become vacant sites by placing ions with an oxidation number greater than that of lithium ions—that is, an oxidation number of 2 or higher—in parts of the lithium sites. The presence of vacant sites within the crystal lattice may facilitate the movement of lithium ions within the crystal lattice.

[0047] In solid ionic conductor compounds represented by Chemical Formula 1, for example, 0 ≤ v / (x+v) < 0.2, and 0 <w / (y+w)<0.2; 0≤v / (x+v)<0.15, 및 0<w / (y+w)<0.15; 또는 0≤v / (x+v)<0.1, 및 0<w / (y+w)<0.1일 수 있다.

[0048] In solid ionic conductor compounds represented by Chemical Formula 1, for example, 0 ≤ v / (x+v) < 0.2, and 0 <w / (y+w+z)<0.2; 0≤v / (x+v)<0.15, 및 0<w / (y+w+z)<0.15; 0≤v / (x+v)<0.1, 및 0<w / (y+w+z)<0.1일 수 있다.

[0049] In solid ion conductor compounds represented by Chemical Formula 1, for example, SO n SO can be S4O6, S3O6, S2O3, S2O4, S2O5, S2O6, S2O7, S2O8, SO4, SO5, or a combination thereof.n It can be, for example, a divalent anion. SO n 2- For example, S4O6 2- , S3O6 2- , S2O3 2- , S2O4 2- , S2O5 2- , S2O6 2- , S2O7 2- , S2O8 2- , SO4 2- , SO5 2- , or a combination of these.

[0050] In solid ionic conductor compounds represented by Chemical Formula 1, for example, 0 ≤ v / (x+v) < 0.08, and 0 <w / (y+w)<0.08이며, SO4를 포함할 수 있다.

[0051] In solid ionic conductor compounds represented by Chemical Formula 1, for example, 0 ≤ v / (x+v) < 0.08, and 0 <w / (y+w+z)<0.08이며, SO4를 포함할 수 있다.

[0052] In a solid ion conductor compound represented by Chemical Formula 1, for example, M1 may include Na, K, Mg, Ag, Cu, Hf, In, Ti, Pb, Sb, Fe, Zr, Zn, Cr, B, Sn, Ge, Si, Zr, Ta, Nb, V, Ga, Al, As, or a combination thereof.

[0053] In a solid ion conductor compound represented by Chemical Formula 1, for example, M1 may include Na, K, Mg, Ag, Cu, or a combination thereof.

[0054] In a solid ion conductor compound represented by Chemical Formula 1, for example, M3 may include F, Cl, Br, I, or a combination thereof.

[0055] A solid ionic conductor compound represented by Chemical Formula 1 may be, for example, a solid ionic conductor compound represented by the following Chemical Formula 2:

[0056] <Chemical Formula 2>

[0057] Li 7-m×v-z M1 v PS 6-w-z M2 w M3 z

[0058] In the above formula, M1 is one or more metallic elements other than Li selected from groups 1 to 15 of the periodic table, m is the oxidation number of M1, and M2 is SO n and M3 is an element selected from Group 17 of the periodic table, and 0≤v<1, 0 <w<2, 0≤z≤2, 1.5≤n≤5, 및 1≤m≤2이다. 예를 들어, m은 1 또는 2이다.

[0059] Suitable monovalent cations selected from groups 1 and 11 of the periodic table are, for example, Na, K, Rb, Cs, Cu, Ag, Mg, etc.

[0060] The solid ion conductor compound represented by Chemical Formula 1 may be, for example, a solid electrolyte compound represented by Chemical Formulas 3 to 4 below:

[0061] <Chemical Formula 3>

[0062] (Li 1-d M1 d ) a P(S 1-e M2 e ) b M3 c

[0063] <Chemical Formula 4>

[0064] (Li 1-d M1 d ) a Li fc P(S 1+fc-e M2 e ) b (M3 1-f M2 f ) c

[0065] In the above formulas, M1 is Na, K, Mg, Ag, Cu, Hf, In, Ti, Pb, Sb, Fe, Zr, Zn, Cr, B, Sn, Ge, Si, Zr, Ta, Nb, V, Ga, Al, As, or a combination thereof, M2 is SO4, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <d≤0.08, 0<e≤0.08, 0<f≤0.08, 0<e+f≤0.08이다.

[0066] In a solid ion conductor compound represented by chemical formula 4, some of the Cl is precipitated as LiCl by, for example, substituting M2 at the S site.

[0067] The solid ion conductor compound represented by Chemical Formula 1 may be, for example, a solid ion conductor compound represented by the following Chemical Formulas 5 to 6:

[0068] <Chemical Formula 5>

[0069] (Li 1-d M1 d ) a P(S 1-e (SO4) e ) b M3 c

[0070] <Chemical Formula 6>

[0071] (Li 1-d M1 d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0072] In the above formulas, M1 is Na, K, Mg, Ag, Cu, or a combination thereof, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <d<0.08, 0<e<0.08, 0<f<0.08, 0<e+f<0.08이다.

[0073] In a solid ion conductor compound represented by chemical formula 6, some of the Cl is precipitated as LiCl by, for example, substituting M2 at the S site.

[0074] The solid ion conductor compound represented by the above chemical formula 1 may be, for example, a solid ion conductor compound represented by the following chemical formulas 5a to 6e:

[0075] <Chemical Formula 5a>

[0076] (Li 1-d Na d ) a P(S 1-e (SO4) e ) b M3 c

[0077] <Chemical Formula 5b>

[0078] (Li 1-d K d ) a P(S 1-e (SO4) e ) b M3 c

[0079] <Chemical Formula 5c>

[0080] (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b M3 c

[0081] <Chemical Formula 5d>

[0082] (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b M3 c

[0083] <Chemical Formula 5e>

[0084] (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b M3c

[0085] <화학식 6a>

[0086] (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0087] <화학식6b>

[0088] (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0089] <화학식 6c>

[0090] (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0091] <화학식6d>

[0092] (Li 1-d Ag d ) a Li fc P(S 1-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0093] <화학식 6e>

[0094] (Li 1-d Cu d ) a Li fc P(S1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0095] In the above equations, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <d≤0.06, 0<e≤0.06, 0<f≤0.06, 0<e+f≤0.06이다.

[0096] In solid ion-conducting compounds represented by chemical formulas 6a to 6e, some of the Cl is precipitated as LiCl by, for example, substituting M2 at the S site.

[0097] The solid ion conductor compound represented by Chemical Formula 1 may be, for example, a solid ion conductor compound represented by the following chemical formulas:

[0098] (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b I c ,

[0099] (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e )b (F 1-f (SO4) f ) c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c ,

[0100] (Li 1-d Na d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b I c ,

[0101] (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c ,

[0102] (Li 1-d K d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d K d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d K d ) a P(S 1-e (SO4) e ) b Br c, (Li 1-d K d ) a P(S 1-e (SO4) e ) b I c ,

[0103] (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c ,

[0104] (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b Cl c, (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b I c ,

[0105] (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c ,

[0106] (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b Fc , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b I c ,

[0107] (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c ,

[0108] In the above equations, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e<0.06, 0<f<0.06, 0<e+f<0.06이다.

[0109] A solid ionic conductor compound represented by Chemical Formula 1 may be, for example, a solid ionic conductor compound represented by the following Chemical Formula 7:

[0110] <Chemical Formula 7>

[0111] Li 7-p×v-u-z M4 v M5 u PS 6-w-z M2 w M3 z

[0112] In the above formula, M4 is a metallic element selected from groups 2 to 15 of the periodic table, p is the oxidation number of M4, and M2 is SO n and, M3 is an element selected from Group 17 of the periodic table, M5 is a metallic element other than Li selected from Group 1 of the periodic table, is a monovalent cation, 0≤v<1, 0≤u<1, 0 <w<2, 0≤z≤2, 1.5≤n≤5, 및 1≤p≤2이다. 예를 들어, p는 1 또는 2이다.

[0113] In the solid ion conductor compound represented by Chemical Formula 7, for example, M4 may include Cu, Ag, Mg, Hf, In, Ti, Pb, Sb, Fe, Zr, Zn, Cr, B, Sn, Ge, Si, Zr, Ta, Nb, V, Ga, Al, As, or a combination thereof. In the solid ion conductor compound represented by Chemical Formula 7, for example, M5 may include Na, K, Rb, Cs, or a combination thereof.

[0114] Suitable monovalent cations selected from Groups 2 and 11 of the periodic table are, for example, Cu, Ag, Mg, etc. Suitable divalent cations selected from Groups 2 and 11 of the periodic table are, for example, Ca, Zn, Fe, etc.

[0115] A solid ionic conductor compound represented by Chemical Formula 1 may be, for example, a solid ionic conductor compound represented by the following Chemical Formula 8:

[0116] <Chemical Formula 8>

[0117] Li 7-z PS 6-w-z M2 w M3 z

[0118] In the above equation, M2 is SO n and, M3 is an element selected from Group 17 of the periodic table, and 0 <w<2, 0≤z≤2, 및 1.5≤n≤5이다.

[0119] The solid ion conductor compound represented by Chemical Formula 1 may be, for example, a solid ion conductor compound represented by the following Chemical Formulas 9 to 10:

[0120] <Chemical Formula 9>

[0121] Li a+fc P(S 1+fc-e M2 e ) b (M3 1-f M2 f ) c

[0122] <Chemical Formula 10>

[0123] Li a P(S 1-e M2 e ) b M3 c

[0124] In the above formulas,

[0125] In the above equations, M2 is SO4, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e≤0.08, 0<f≤0.08, 0<e+f≤0.08이다. 화학식 9로 표시되는 고체이온전도체 화합물에서 예를 들어 S 자리에 M2가 치환됨에 의하여 Cl의 일부가 LiCl로 석출된다.

[0126] The solid ion conductor compound represented by Chemical Formula 1 may be, for example, a solid ion conductor compound represented by Chemical Formulas 11 to 12 below:

[0127] <Chemical Formula 11>

[0128] Li a+fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c

[0129] <Chemical Formula 12>

[0130] Li a P(S 1-e (SO4) e ) b M3 c

[0131] In the above equations, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e<0.08, 0<f<0.08, 0<e+f<0.08이다.

[0132] In a solid ion-conducting compound represented by chemical formula 11, some of the Cl is precipitated as LiCl by, for example, substituting M2 at the S site.

[0133] The solid ion conductor compound represented by Chemical Formula 1 may be, for example, a solid ion conductor compound represented by the following chemical formulas:

[0134] Li a+fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , Li a+fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , Li a+fc P(S 1+fc-e (SO4) e ) b (Br1-f (SO4) f ) c , Li a+fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c ,

[0135] Li a P(S 1-e (SO4) e ) b F c , Li a P(S 1-e (SO4) e ) b Cl c , Li a P(S 1-e (SO4) e ) b Br c , Li a P(S 1-e (SO4) e ) b I c ,

[0136] In the above equations, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e<0.06, 0<f<0.06, 0<e+f<0.06이다.

[0137] A solid ion conductor compound represented by Chemical Formula 1 provides enhanced lithium ion conductivity. The solid ion conductor compound represented by Chemical Formula 1 provides ion conductivity of 1.0 mS / cm or more, 1.5 mS / cm or more, 2.0 mS / cm or more, 2.5 mS / cm or more, 3.0 mS / cm or more, 3.5 mS / cm or more, 4.0 mS / cm or more, or 5.0 mS / cm or more at room temperature, for example, about 25°C. A solid ion conductor compound represented by Chemical Formula 1 provides ion conductivity of 1.0 to 500 mS / cm, 1.5 to 400 mS / cm, 2.0 to 300 mS / cm, 2.5 to 200 mS / cm, 3.0 to 150 mS / cm, 3.5 to 100 mS / cm, 4.0 to 100 mS / cm, or 5.0 to 100 mS / cm at room temperature, for example, about 25°C. Thus, in an electrochemical cell comprising an anode; a cathode; and a solid ion conductor compound represented by Chemical Formula 1 disposed between the anode and the cathode, ion transfer between the anode and the cathode can be effectively carried out, thereby reducing the internal resistance between the anode and the cathode. Ion conductivity can be measured using the DC polarization method. Alternatively, ionic conductivity can be measured using the complex impedance method.

[0138] A solid ion-conducting compound represented by Chemical Formula 1 may have an ion conductivity retention rate of 70% or more, 75% or more, or 80% or more after 10 days under dry conditions in an air atmosphere having a dew point of, for example, less than -60°C. The ion conductivity retention rate may be represented, for example, by the following Equation 1. In the following Equation 1, the initial ion conductivity of the solid ion-conducting compound refers to the ion conductivity of the solid ion-conducting compound before storage under dry conditions. The ion conductivity retention rate can be measured by the method disclosed in Evaluation Example 3.

[0139] <Mathematical Formula 1>

[0140] Ionic conductivity retention rate = [Ionic conductivity of solid ion-conducting compound after 10 days / Ionic conductivity of solid ion-conducting compound at initial] × 100

[0141] The solid ion-conducting compound represented by Chemical Formula 1 belongs, for example, to the cubic crystal system, and more specifically, may belong to the F-43m space group. Additionally, the solid ion-conducting compound represented by Chemical Formula 1 may be an argyrodite-type oxide having an argyrodite-type crystal structure. In the argyrodite-type crystal structure, the solid ion-conducting compound represented by Chemical Formula 1 has SO4 at some of the sulfur (S) sites. 2- Since it contains oxygen atoms by being substituted with anions, it can simultaneously provide enhanced lithium ion conductivity, enhanced oxidation resistance for lithium metal, and enhanced atmospheric stability. In addition, the solid ion conductor compound represented by Chemical Formula 1 has M1 at some of the lithium sites in an azyrodite-type crystal structure. + Cation element, M1 2+ Cation elements and M1 3+ By substituting one or more of the cation elements, it is possible to simultaneously provide enhanced lithium ion conductivity and electrochemical stability for lithium metal.

[0142] Referring to FIG. 1c, the solid ion conductor compound represented by Formula 1 includes, for example, a first peak at a diffraction angle 2θ = 30.1°±0.5° and a second peak at a diffraction angle 2θ = 31.5°±0.5° in an XRD spectrum using CuKα rays, and a compound having the same composition as the solid ion conductor compound represented by Formula 1, except that M2 is changed to S, includes a third peak at a diffraction angle 2θ = 30.1°±0.5° and a fourth peak at a diffraction angle 2θ = 31.5°±0.5° in an XRD spectrum using CuKα rays, and the positions of the first and second peaks can be downshifted by at least 0.01°, at least 0.02°, at least 0.03°, or at least 0.04°, respectively, compared to the third and fourth peaks. This downshift of the peak is due to the increase in the interplanar distance of the crystal lattice caused by the substitution of SO4, which has a larger ionic radius compared to sulfur (S). Solid ion conductor compounds having such an increased interplanar distance of the crystal lattice can provide enhanced oxidation resistance and atmospheric stability.

[0143] Referring to FIG. 1b, the solid ion conductor compound represented by Formula 1 may further include a peak corresponding to LiM3 reprecipitated by M2 at a diffraction angle 2θ = 35.0°±1.0° in an XRD spectrum using CuKα lines, for example. This LiM3 is, for example, LiCl. A solid ion conductor compound having this additional peak can provide enhanced oxidation resistance and atmospheric stability.

[0144] [Solid Electrolyte]

[0145] A solid electrolyte according to another embodiment comprises a solid ion-conducting compound represented by the above-described Chemical Formula 1. By including such a solid ion-conducting compound, the solid electrolyte can have high ion conductivity and high chemical stability. A solid electrolyte comprising the solid ion-conducting compound represented by Chemical Formula 1 can provide improved stability against air and electrochemical stability against lithium metal. Accordingly, the solid ion-conducting compound represented by Chemical Formula 1 can be used, for example, as a solid electrolyte in an electrochemical cell.

[0146] The solid electrolyte may additionally include conventional general solid electrolytes in addition to the solid ion conductor compound represented by Chemical Formula 1. For example, it may additionally include conventional general sulfide-based solid electrolytes and / or oxide-based solid electrolytes. The additionally included conventional solid ion conductor compounds are, for example, Li2O-Al2O3-TiO2-P2O5 (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 S4), Li2S, Li2S-P2S5, Li2S-SiS2, Li2S-GeS2, Li2S-B2S5, and Li2S-Al2S5, etc., may be used, but are not necessarily limited to these, and any that can be used in the relevant technical field is acceptable.

[0147] Solid electrolytes may be in the form of powder or molded articles. Solid electrolytes in the form of molded articles may be, for example, pellets, sheets, or thin films, but are not necessarily limited to these and can take various forms depending on the application.

[0148] [Electrochemical Cell]

[0149] An electrochemical cell according to another embodiment comprises: a positive electrode layer including a positive active material layer; a negative electrode layer including a negative active material layer; and an electrolyte layer disposed between the positive electrode layer and the negative electrode layer, wherein the positive active material layer and / or the electrolyte layer comprises a solid ion conductor compound represented by Formula 1. By including a solid ion conductor compound represented by Formula 1, the lithium ion conductivity and stability against lithium metal of the electrochemical cell are improved.

[0150] The electrochemical cell may be, for example, an all-solid-state secondary battery, a secondary battery containing a liquid electrolyte, or a lithium-air battery, but is not necessarily limited to these; any electrochemical cell usable in the relevant technical field is acceptable.

[0151] In the following, solid-state secondary batteries will be explained in more detail.

[0152] [All-solid-state secondary battery: Type 1]

[0153] All-solid-state secondary batteries may include a solid ion-conducting compound represented by Chemical Formula 1.

[0154] A solid-state secondary battery comprises, for example, a positive electrode layer including a positive active material layer; a negative electrode layer including a negative active material layer; and an electrolyte layer disposed between the positive electrode layer and the negative electrode layer, wherein the positive active material layer and / or the electrolyte layer may comprise a solid ion-conducting compound represented by Chemical Formula 1.

[0155] An all-solid-state secondary battery according to one embodiment can be prepared as follows.

[0156] (Solid electrolyte layer)

[0157] First, a solid electrolyte layer is prepared.

[0158] A solid electrolyte layer can be prepared by mixing and drying a solid ion-conducting compound represented by Chemical Formula 1 with a binder, or by rolling a powder of a solid ion-conducting compound represented by Chemical Formula 1 into a specific shape under a pressure of 1 ton to 10 ton. A solid ion-conducting compound represented by Chemical Formula 1 is used as a solid electrolyte.

[0159] The average particle size of the solid electrolyte may be, for example, 0.5 µm to 20 µm. Since the solid electrolyte has such an average particle size, the binding properties are improved during the sintering process, which can improve the ionic conductivity and lifespan characteristics of the solid electrolyte particles.

[0160] The thickness of the solid electrolyte layer can be 10 µm to 200 µm. By having such a thickness of the solid electrolyte layer, a sufficient mobility of lithium ions is ensured, and as a result, high ionic conductivity can be obtained.

[0161] 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-conducting compound represented by Chemical Formula 1.

[0162] Conventional sulfide-based solid electrolytes may comprise, for example, lithium sulfide, silicon sulfide, phosphorus sulfide, boron sulfide, or combinations thereof. Conventional sulfide-based solid electrolyte particles may comprise Li2S, P2S5, SiS2, GeS2, B2S3, or combinations thereof. Conventional sulfide-based solid electrolyte particles may be Li2S or P2S5. Conventional sulfide-based solid electrolyte particles are known to have high lithium ion conductivity compared to other inorganic compounds. For example, conventional sulfide-based solid electrolytes comprise Li2S and P2S5. When the sulfide solid electrolyte material constituting the conventional sulfide-based solid electrolyte comprises Li2S-P2S5, the mixed molar ratio of Li2S to P2S5 may be, for example, in the range of about 50:50 to about 90:10. In addition, Li3PO4, halogen, halogen compound, Li 2+2x Zn 1-x GeO4("LISICON", 0≤x<1), Li 3+y PO 4-x N x( "LIPON", 0≤x<4, 0≤y≤4), Li 3.25 Ge 0.25 P 0.75 S4("ThioLISICON"), Li2O-Al2O3-TiO2-P2O 5( Inorganic solid electrolytes prepared by adding "LATP," etc., to inorganic solid electrolytes of Li2S-P2S5, SiS2, GeS2, B2S3, or combinations thereof can be used as conventional sulfide solid electrolytes. Non-limiting examples of conventional sulfide solid electrolyte materials include Li2S-P2S5; Li2S-P2S5-LiX (where X is a halogen element); Li2S-P2S5-Li2O; Li2S-P2S5-Li2O-LiI; Li2S-SiS2; Li2S-SiS2-LiI; Li2S-SiS2-LiBr; Li2S-SiS2-LiCl; Li2S-SiS2-B2S3-LiI; Li2S-SiS2-P2S5-LiI; Li2S-B2S3; Li2S-P2S5-Z m S n(m and n are positive numbers, and Z is Ge, Zn, or G); Li2S-GeS2; Li2S-SiS2-Li3PO4; and Li2S-SiS2-Li p MO q (In the above formula, p and q are positive numbers, and M is P, Si, Ge, B, Al, Ga, or In). In this regard, conventional sulfide-based solid electrolyte materials can be manufactured by processing raw material starting materials of sulfide-based solid electrolyte materials (e.g., Li2S, P2S5, etc.) by a melt quenching method, mechanical milling method, etc. Additionally, a calcination process may be performed after the above processing.

[0163] The binder included in the solid electrolyte layer is, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polyvinyl alcohol, etc., but is not limited to these, and any binder used in the relevant technical field is acceptable. The binder of the solid electrolyte layer may be of the same type as or different from the binder of the anode layer and the cathode layer.

[0164] (Bipolar layer)

[0165] Next, the anode layer is prepared.

[0166] The positive layer can be manufactured by forming a positive active material layer containing a positive active material on a current collector. The average particle size of the positive active material may be, for example, 2 µm to 10 µm.

[0167] Any cathode active material commonly used in secondary batteries may be used without restriction. For example, it may be lithium transition metal oxides, transition metal sulfides, etc. For example, one or more composite oxides of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof may be used, and specific examples include Li a A 1-b B b D2(wherein 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 (In the above equation, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05); Li a Ni 1-b-c Co b B c D α (In the above equation, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α ≤ 2); Li a Ni 1-b-c Co b B c O 2-α F α (In the above equation, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni 1-b-c Co b B c O 2-α F2(wherein, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni 1-b-c Mn b B c D α(In the above equation, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α ≤ 2); Li a Ni 1-b-c Mn b B c O 2-α F α (In the above equation, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni 1-b-c Mn b B c O 2-α F2(wherein, 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, 0 < α < 2); Li a Ni b E c G d O2(wherein 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 GeO2(wherein 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 O2(in the above equation, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a CoG b O2(in the above equation, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a MnG b O2(in the above equation, 0.90 ≤ a ≤ 1.8, 0.001 ≤ b ≤ 0.1); Li a Mn2G bO4(wherein 0.90 ≤ a ≤ 1.8 and 0.001 ≤ b ≤ 0.1); QO2; QS2; LiQS2; V2O5; LiV2O2; LiIO2; LiNiVO4; Li (3-f) J2(PO4)3(0 ≤ f ≤ 2); Li (3-f) Compounds represented by any one of the chemical formulas of Fe2(PO4)3 (0 ≤ f ≤ 2); LiFePO4 may be used. In the above chemical formulas, A is Ni, Co, Mn, or a combination thereof; B is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination 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; and J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof. For example, LiCoO2, LiMn x O 2x (x=1, 2), LiNi 1-x Mn x O 2x (0 <x<1), Ni 1-x-y Co x Mn y O2(0≤x≤0.5, 0≤y≤0.5), Ni 1-x-y Co x Al yO2 (0≤x≤0.5, 0≤y≤0.5), LiFePO4, TiS2, FeS2, TiS3, FeS3, etc. In these compounds, A is Ni, Co, Mn, or a combination thereof; B is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination 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; and J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof. It is also possible to use a compound with a coating layer added to the surface of such a compound, and it is also possible to use a mixture of the above-described compound and a compound with a coating layer added. The coating layer applied to the surface of such a compound comprises, for example, a coating element compound of an oxide, hydroxide, oxyhydroxide, oxycarbonate, or hydroxycarbonate of a coating element. The compound forming this coating layer is amorphous or crystalline. The coating elements included in the coating layer are Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof. The method for forming the coating layer is selected within a range that does not adversely affect the physical properties of the cathode active material. The coating method is, for example, spray coating or immersion. Since specific coating methods are well understood by those skilled in the art, a detailed explanation will be omitted.

[0168] The cathode 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, a cubic rock salt type structure. <111> It is a structure in which oxygen and metal atomic layers are alternately and regularly arranged in a specific direction, thereby forming a two-dimensional plane for each layer. The "cubic rock salt type structure" represents a sodium chloride (NaCl type) structure, which is a type of crystal structure; specifically, it exhibits a structure in which the face-centered cubic lattices (fcc) formed by cations and anions, respectively, are offset from each other by half the ridge of the unit lattice. Lithium transition metal oxides having such a layered rock salt type structure are, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mn z It is a ternary lithium transition metal oxide such as O2(NCM) (0 < x < 1, 0 < y < 1, 0 < z < 1, x + y + z = 1). When the positive electrode active material includes a ternary lithium transition metal oxide having a layered rock salt structure, the energy density and thermal stability of the all-solid-state secondary battery (1)(1) are further improved.

[0169] As described above, the positive electrode active material may be covered by a coating layer. The coating layer may be any material known as a coating layer for the positive electrode active material of an all-solid-state secondary battery. For example, the coating layer is Li2O-ZrO2 (LZO), etc.

[0170] When the cathode active material is a ternary lithium transition metal oxide, such as NCA or NCM, containing nickel (Ni), it is possible to increase the capacity density of the all-solid-state secondary battery and reduce metal leaching from the cathode active material during charging. Consequently, the cycle characteristics of the all-solid-state secondary battery during charging are improved.

[0171] The shape of the positive active material is, for example, a particle shape such as a sphere, an elliptical sphere, etc. The particle size of the positive active material is not particularly limited and is within a range applicable to the positive active material of a conventional all-solid-state secondary battery. The content of the positive active material in the positive layer is also not particularly limited and is within a range applicable to the positive layer of a conventional all-solid-state secondary battery. The content of the positive active material in the positive active material layer may be, for example, 50 to 95 weight%.

[0172] The positive active material layer may additionally include a solid ion conductor compound represented by Chemical Formula 1.

[0173] The positive active material layer may include a binder. Examples of binders include styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc.

[0174] The cathode 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, etc.

[0175] The positive electrode active material layer may further include additives such as fillers, coating agents, dispersants, and ion conductivity aids in addition to the aforementioned positive electrode active material, solid electrolyte, binder, and conductive material.

[0176] As fillers, coating agents, dispersants, ion conductivity aids, etc. that may be included in the positive electrode active material layer, known materials generally used in electrodes of all-solid-state secondary batteries can be used.

[0177] The positive current collector uses, for example, a plate or foil made of aluminum (Al), indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), germanium (Ge), lithium (Li), or alloys thereof. The positive current collector may be omitted.

[0178] The positive current collector may further include a carbon layer disposed on one or both sides of a metal substrate. By additionally disposing of a carbon layer on the metal substrate, the metal of the metal substrate may be prevented from being corroded by the solid electrolyte contained in the positive layer, and the interfacial resistance between the positive active material layer and the positive current collector may be reduced. The thickness of the carbon layer may be, for example, 1 µm to 5 µm. If the thickness of the carbon layer is excessively thin, it may be difficult to completely block contact between the metal substrate and the solid electrolyte. If the thickness of the carbon layer is excessively thick, the energy density of the all-solid-state secondary battery may decrease. The carbon layer may include amorphous carbon, crystalline carbon, etc.

[0179] (Cathode layer)

[0180] Next, the cathode layer is prepared.

[0181] The cathode layer can be manufactured in the same manner as the anode layer, except that a cathode active material is used instead of an anode active material. The cathode layer can be manufactured by forming a cathode active material layer containing the cathode active material on a cathode current collector.

[0182] The negative electrode active material layer may additionally include a solid ion conductor compound represented by Chemical Formula 1 described above.

[0183] The negative electrode active material may be lithium metal, a lithium metal alloy, or a combination thereof.

[0184] The negative electrode active material layer may further include a conventional negative electrode active material in addition to lithium metal, a 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. The metal alloyable with lithium may be, for example, Ag, Si, Sn, Al, Ge, Pb, Bi, Sb Si-Y alloy (wherein Y is an alkali metal, alkaline earth metal, group 13 element, group 14 element, transition metal, rare earth element, or a combination thereof, and is not Si), Sn-Y alloy (wherein Y is an alkali metal, alkaline earth metal, group 13 element, group 14 element, transition metal, rare earth element, or a combination thereof, and is not Sn), etc. The above element Y may be 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, Se, Te, Po, or a combination thereof. The transition metal oxide may be, for example, lithium titanium oxide, vanadium oxide, lithium vanadium oxide, etc. The non-transition metal oxide may be, for example, SnO2, SiO2 x (0 <x<2) 등일 수 있다. 탄소계 재료는 예를 들어 결정질 탄소, 비정질 탄소 또는 이들의 혼합물일 수 있다. 결정질 탄소는 무정형, 판상, 린편상(flake), 구형 또는 섬유형의 천연 흑연 또는 인조 흑연과 같은 흑연일 수 있으며, 상기 비정질 탄소는 소프트 카본(soft carbon: 저온 소성 탄소) 또는 하드 카본(hard carbon), 메조페이스 피치(mesophase pitch) 탄화물, 소성된 코크스 등일 수 있다.

[0185] Referring to FIG. 2, an all-solid-state secondary battery (40) according to one embodiment includes a solid electrolyte layer (30), a positive electrode layer (10) disposed on one side of the solid electrolyte layer (30), and a negative electrode layer (20) disposed on the other side of the solid electrolyte layer (30). The positive electrode layer (30) includes a positive active material layer (12) in contact with the solid electrolyte layer (30) and a positive current collector (11) in contact with the positive active material layer (12), and the negative electrode layer (20) includes a negative active material layer (22) in contact with the solid electrolyte layer (30) and a negative current collector (21) in contact with the negative active material layer (22). The all-solid-state secondary battery (40) is completed, for example, by forming a positive active material layer (12) and a negative active material layer (22) on both sides of a solid electrolyte layer (30), and forming a positive current collector (11) and a negative current collector (21) respectively on the positive active material layer (12) and the negative active material layer (22). Alternatively, the all-solid-state secondary battery (40) is completed, for example, by sequentially stacking a negative active material layer (22), a solid electrolyte layer (30), a positive active material layer (12), and a positive current collector (11) on a negative current collector (21).

[0186] [All-solid-state secondary battery: Type 2]

[0187] Referring to FIG. 3 and 4, the all-solid-state secondary battery (1) comprises, for example, a positive electrode layer (10) comprising a positive active material layer (12) disposed on a positive current collector (11); a negative electrode layer (20) comprising a negative active material layer (22) disposed on a negative current collector (21); and an electrolyte layer (30) disposed between the positive electrode layer (10) and the negative electrode layer (20), wherein the positive active material layer (12) and / or the electrolyte layer (30) may comprise a solid ion-conducting compound represented by Chemical Formula 1.

[0188] An all-solid-state secondary battery according to another embodiment can be prepared as follows.

[0189] The anode layer and the solid electrolyte layer are manufactured in the same way as the all-solid-state secondary battery described above.

[0190] (Cathode layer)

[0191] Next, the cathode layer is prepared.

[0192] Referring to FIGS. 3 and 4, the cathode layer (20) comprises a cathode current collector (21) and a cathode active material layer (22) disposed on the cathode current collector (21), and the cathode active material layer (22) comprises, for example, a cathode active material and a binder.

[0193] The negative electrode active material included in the negative electrode active material layer (22) has, for example, a particle shape. The average particle size of the negative electrode active material having a particle shape is, for example, 4 µm or less, 3 µm or less, 2 µm or less, 1 µm or less, or 900 nm or less. The average particle size of the negative electrode active material having a particle shape is, for example, 10 nm to 4 µm or less, 10 nm to 3 µm or less, 10 nm to 2 µm or less, 10 nm to 1 µm or less, or 10 nm to 900 nm or less. By having the negative electrode active material with an average particle size within this range, the reversible absorption and / or desorption of lithium during charging and discharging may be more easily facilitated. The average particle size of the negative electrode active material is, for example, the median diameter (D50) measured using a laser particle size distribution meter.

[0194] The cathode active material included in the cathode active material layer (22) comprises, for example, one or more selected from carbon-based cathode active materials and metal or metalloid cathode active materials.

[0195] The carbon-based cathode active material is, in particular, amorphous carbon. Amorphous carbon is, for example, carbon black (CB), acetylene black (AB), furnace black (FB), ketjen black (KB), graphene, etc., but is not necessarily limited to these, and any material classified as amorphous carbon in the relevant technical field is acceptable. Amorphous carbon is carbon that does not have crystallinity or has very low crystallinity, and is distinguished from crystalline carbon or graphite-based carbon.

[0196] The metal or metalloid cathode active material comprises one or more selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn), but is not necessarily limited to these; any metal cathode active material or metalloid cathode active material that forms an alloy or compound with lithium in the relevant technical field is acceptable. For example, nickel (Ni) is not a metal cathode active material because it does not form an alloy with lithium.

[0197] The negative electrode active material layer (22) may include a type of negative electrode active material among these negative electrode active materials, or may include a mixture of multiple different negative electrode active materials. For example, the negative electrode active material layer (22) may include only amorphous carbon, or one or more selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). Alternatively, the negative electrode active material layer (22) may include a mixture of amorphous carbon and one or more selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). The mixing ratio of a mixture of amorphous carbon and gold, etc., is, for example, 10:1 to 1:2, 5:1 to 1:1, or 4:1 to 2:1 by weight ratio, but is not necessarily limited to these ranges and is selected according to the required characteristics of the all-solid-state secondary battery (1). By having the negative electrode active material have this composition, the cycle characteristics of the all-solid-state secondary battery (1) are further improved.

[0198] The negative electrode active material included in the negative electrode active material layer (22) comprises a mixture of first particles made of, for example, amorphous carbon and second particles made of a metal or metalloid. The metal or metalloid includes, for example, gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). Alternatively, the metalloid is a semiconductor. The content of the second particles is 8 to 60 weight%, 10 to 50 weight%, 15 to 40 weight%, or 20 to 30 weight% based on the total weight of the mixture. By having the second particles in this range, the cycle characteristics of, for example, the all-solid-state secondary battery (1) are further improved.

[0199] The binder included in the negative electrode active material layer (22) may be, for example, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, polymethyl methacrylate, etc., but is not necessarily limited to these and any binder used in the relevant technical field is possible. The binder may be composed of a single binder or a plurality of different binders.

[0200] The negative active material layer (22) is stabilized on the negative current collector (21) by including a binder. Additionally, cracking of the negative active material layer (22) is suppressed despite changes in volume and / or relative position of the negative active material layer (22) during the charging and discharging process. For example, if the negative active material layer (22) does not include a binder, it is possible for the negative active material layer (22) to be easily separated from the negative current collector (21). As the negative active material layer (22) is separated from the negative current collector (21), the possibility of a short circuit occurring increases as the negative current collector (21) comes into contact with the solid electrolyte layer (30) in the exposed portion of the negative current collector (21). The negative active material layer (22) is manufactured, for example, by applying a slurry in which the material constituting the negative active material layer (22) is dispersed onto the negative current collector (21) and drying it. By including a binder in the negative electrode active material layer (22), stable dispersion of the negative electrode active material in the slurry is possible. For example, when the slurry is applied onto the negative electrode current collector (21) by a screen printing method, it is possible to suppress clogging of the screen (e.g., clogging by aggregates of the negative electrode active material).

[0201] The negative electrode active material layer (22) may further include additives used in conventional all-solid-state secondary batteries (1), such as fillers, coating agents, dispersants, ion-conducting aids, etc.

[0202] 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 layer (12). The thickness of the negative electrode active material layer (22) is, for example, 1 µm to 20 µm, 2 µm to 10 µm, or 3 µm to 7 µm. If the thickness of the negative electrode active material layer (22) is excessively thin, lithium dendrites formed between the negative electrode active material layer (22) and the negative electrode current collector (21) cause the negative electrode active material layer (22) to collapse, making it difficult to improve the cycle characteristics of the all-solid-state secondary battery (1). If the thickness of the negative electrode active material layer (22) increases excessively, the energy density of the all-solid-state secondary battery (1) decreases and the internal resistance of the all-solid-state secondary battery (1) due to the negative electrode active material layer (22) increases, making it difficult to improve the cycle characteristics of the all-solid-state secondary battery (1).

[0203] If the thickness of the negative electrode active material layer (22) decreases, for example, the charging capacity of the negative electrode active material layer (22) also decreases. The charging capacity 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, 5% or less, or 2% or less compared to the charging capacity of the positive electrode active material layer (12). 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% to 10%, 0.1% to 5%, or 0.1% to 2% compared to the charging capacity of the positive electrode active material layer (12). If the charge capacity of the negative electrode active material layer (22) is excessively small, the thickness of the negative electrode active material layer (22) becomes very thin, and thus, during repeated charge and discharge processes, lithium dendrites formed between the negative electrode active material layer (22) and the negative electrode current collector (21) cause the negative electrode active material layer (22) to collapse, making it difficult to improve the cycle characteristics of the all-solid-state secondary battery (1). If the charge capacity of the negative electrode active material layer (22) increases excessively, the energy density of the all-solid-state secondary battery (1) decreases, and the internal resistance of the all-solid-state secondary battery (1) caused by the negative electrode active material layer (22) increases, making it difficult to improve the cycle characteristics of the all-solid-state secondary battery (1).

[0204] The charge capacity of the positive active material layer (12) is obtained by multiplying the charge capacity density (mAh / g) of the positive active material by the mass of the positive active material in the positive active material layer (12). When multiple types of positive active materials are used, the charge capacity density × mass value is calculated for each positive active material, and the sum of these values ​​is the charge capacity of the positive active material layer (12). The charge capacity of the negative active material layer (22) is calculated in the same way. That is, the charge capacity of the negative active material layer (22) is obtained by multiplying the charge capacity density (mAh / g) of the negative active material by the mass of the negative active material in the negative active material layer (22). When multiple types of negative active materials are used, the charge capacity density × mass value is calculated for each negative active material, and the sum of these values ​​is the capacity of the negative active material layer (22). Here, the charge capacity densities of the positive active material and the negative active material are the capacity estimated using an all-solid-state half-cell using lithium metal as the counter electrode. The charge capacity of the positive active material layer (12) and the negative active material layer (22) is directly measured by measuring the charge capacity using an all-solid half-cell. By dividing the measured charge capacity by the mass of each active material, the charge capacity density is obtained. Alternatively, the charge capacity of the positive active material layer (12) and the negative active material layer (22) may be the initial charge capacity measured during the first cycle of charging.

[0205] Referring to FIG. 4, the all-solid-state secondary battery (1a) may further include a metal layer (23) disposed between, for example, a negative electrode current collector (21) and a negative electrode active material layer (22). The metal layer (23) comprises lithium or a lithium alloy. Thus, the metal layer (23) acts as, for example, a lithium reservoir. The lithium alloy is, for example, a Li-Al alloy, a Li-Sn alloy, a Li-In alloy, a Li-Ag alloy, a Li-Au alloy, a Li-Zn alloy, a Li-Ge alloy, a Li-Si alloy, etc., but is not limited to these, and any alloy used as a lithium alloy in the relevant technical field is possible. The metal layer (23) may be made of one of these alloys or lithium, or may be made of various types of alloys.

[0206] The thickness of the metal layer (23) is not particularly limited, but is, for example, 1 µm to 1000 µm, 1 µm to 500 µm, 1 µm to 200 µm, 1 µm to 150 µm, 1 µm to 100 µm, or 1 µm to 50 µm. If the thickness of the metal layer (23) is excessively thin, it is difficult for the metal layer (23) to perform the role of a lithium reservoir. If the thickness of the metal layer (23) is excessively thick, the mass and volume of the all-solid-state secondary battery (1) may increase, and the cycle characteristics may actually deteriorate. The metal layer (23) may be, for example, a metal foil having a thickness within this range.

[0207] In the all-solid-state 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 assembly of the all-solid-state secondary battery (1), or is deposited between the negative electrode current collector (21) (21, 21a, 21b) and the negative electrode active material layer (22) by charging after assembly of the all-solid-state secondary battery (1). When the metal layer (23) is disposed between the negative electrode current collector (21) and the negative electrode active material layer (22) before assembly of the all-solid-state secondary battery (1a), the metal layer (23) acts as a lithium reservoir because it is a metal layer containing lithium. For example, a lithium foil is disposed between the negative electrode current collector (21) and the negative electrode active material layer (22) before assembly of the all-solid-state secondary battery (1a). Accordingly, the cycle characteristics of the all-solid-state secondary battery (1a) including the metal layer (23) are further improved. When the metal layer (23) is precipitated by charging after assembly of the all-solid-state secondary battery (1a), the energy density of the all-solid-state secondary battery (1a) increases because the metal layer (23) is not included during assembly of the all-solid-state secondary battery (1a). For example, when charging the all-solid-state secondary battery (1), it is charged beyond the charging capacity of the negative electrode active material layer (22). That is, the negative electrode active material layer (22) is overcharged. At the beginning of charging, lithium is absorbed 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 that have moved from the positive electrode layer (10). When charging is performed beyond the capacity of the negative electrode active material layer (22), lithium is deposited, for example, on the back 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), and a metal layer corresponding to the metal layer (23) is formed by the deposited lithium. The metal layer (23) is a metal layer composed mainly of lithium (i.e., metallic lithium). This result is obtained, for example, by the negative electrode active material included in the negative electrode active material layer (22) being composed of a material that forms an alloy or compound with lithium. During discharge, the lithium in the negative electrode active material layer (22) and the metal layer (23), that is, the metal layer, is ionized and moves toward the positive electrode layer (10).Therefore, it is possible to use lithium as a negative electrode active material in an all-solid-state secondary battery (1a). In addition, since the negative electrode active material layer (22) covers the metal layer (23), it acts as a protective layer for the metal layer (23) and simultaneously suppresses the precipitation growth of lithium dendrites. Thus, it suppresses short circuits and capacity degradation of the all-solid-state secondary battery (1a), and consequently improves the cycle characteristics of the all-solid-state secondary battery (1a). Furthermore, when the metal layer (23) is placed by charging after assembly of the all-solid-state secondary battery (1a), the negative electrode current collector (21), the negative electrode active material layer (22), and the region between them are, for example, Li-free regions that do not contain lithium (Li) in the initial state or after discharge state of the all-solid-state secondary battery (1a).

[0208] The negative electrode current collector (21) is composed of a material that does not react with, for example, lithium, that is, does not form any alloys or compounds. The material constituting the negative electrode current collector (21) may be, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni), but is not necessarily limited to these; any material used as an electrode current collector in the relevant technical field is acceptable. The negative electrode current collector (21) may be composed of one of the metals described above, or may be composed of an alloy or coating material of two or more metals. The negative electrode current collector (21) is, for example, in the form of a plate or foil.

[0209] The all-solid-state secondary battery (1) may further include a thin film containing an element capable of forming an alloy with lithium, for example, on a 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. The 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 to these, and any element capable of forming an alloy with lithium in the relevant technical field is possible. The thin film is composed of one of these metals or is composed of an alloy of various types of metals. By disposing of the thin film on the negative electrode current collector (21), the deposition pattern of the metal layer (23) deposited between, for example, the thin film (24) and the negative electrode active material layer (22) is further flattened, and the cycle characteristics of the all-solid-state secondary battery (1) can be further improved.

[0210] 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. If the thickness of the thin film is less than 1 nm, it may be difficult to perform the function provided by the thin film. If the thickness of the thin film is excessively thick, the thin film itself absorbs lithium, and the amount of lithium precipitated at the negative electrode decreases, which lowers the energy density of the all-solid-state battery and may degrade the cycle characteristics of the all-solid-state secondary battery (1). The thin film may be placed on the negative electrode current collector (21, 21a, 21b) by, for example, vacuum deposition, sputtering, plating, etc., but is not necessarily limited to these methods, and any method capable of forming a thin film in the relevant technical field is possible.

[0211] A method for manufacturing a solid ion conductor compound according to another embodiment comprises: a compound containing lithium; a compound containing a metal element other than Li selected from groups 1 to 15 of the periodic table; a compound containing phosphorus (P); a compound containing sulfur (S); and SOn The method comprises the steps of: contacting a compound containing (1.5≤n≤5); and optionally a compound containing a Group 17 element to provide a mixture; and heat-treating the mixture in an inert atmosphere to provide a solid ion-conducting compound. The solid ion-conducting compound is, for example, a solid ion-conducting compound represented by Chemical Formula 1. The compound containing a Group 17 element may be omitted.

[0212] Compounds containing lithium include lithium-containing sulfides. For example, lithium sulfide is mentioned.

[0213] Compounds containing metal elements other than Li selected from Groups 1 to 15 of the periodic table include sulfides that contain elements selected from Groups 1 to 15 of the periodic table and do not contain Li. For example, copper sulfide, silver sulfide, sodium sulfide (Na₂S₂S₂). 2 S), magnesium sulfide, potassium sulfide (K2S), etc. are mentioned.

[0214] Compounds containing phosphorus (P) include phosphorus-containing sulfides. For example, P2S5 is mentioned.

[0215] SO n Compounds containing (1.5≤n≤5) include lithium salts containing SOn. For example, Li2S4O6, Li2S3O6, Li2S2O3, Li2S2O4, Li2S2O5, Li2S2O6, Li2S2O7, Li2S2O8, Li2SO4, Li2SO5, etc. are mentioned.

[0216] Compounds containing Group 17 elements include lithium salts containing Group 17 elements. For example, LiCl, LiF, LiBr, and LiI are mentioned.

[0217] These compounds can be prepared by contacting starting materials in appropriate amounts, for example, stoichiometric amounts, to form a mixture, and then heat-treating the mixture. The contact may include milling or grinding, for example, ball milling.

[0218] A mixture of precursors mixed with stoichiometric composition can be heat-treated in an inert atmosphere to produce a solid ion conductor compound.

[0219] Heat treatment is, for example, 400 to 700℃, 400 Up to 650℃, 400 Up to 600℃, 400 It may be performed at 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 may be, for example, nitrogen, argon, etc., but is not necessarily limited to these; any gas used as an inert gas in the relevant technical field is acceptable.

[0220] The creative idea is explained in more detail through the following examples and comparative examples. However, the examples are intended to illustrate the creative idea and do not limit the scope of the creative idea to these examples alone.

[0221] (Preparation of solid ion-conducting compounds)

[0222] Example 1: (Li 5.69 Cu 0.06 )P(S 4.70 (SO 4 ) 0.05 )Cl 1.25 manufacturing

[0223] In a glove box under an Ar atmosphere, the lithium precursor Li2S, the phosphorus (P) precursor P2S5, the chlorine (Cl) precursor LiCl, the copper (Cu) precursor Cu2S, and the SO4 precursor Li2SO4 are prepared in the desired composition (Li 5.69 Cu 0.06 )P(S 4.70(SO4) 0.05 )Cl 1.25 After combining in stoichiometric ratios to obtain [the desired result], the mixture was ground and mixed at 100 rpm for 1 hour in a planetary ball mill in an Ar atmosphere containing zirconia (YSZ) balls, followed by grinding and mixing at 800 rpm for 30 minutes to obtain a mixture. The obtained mixture was pressed under uniaxial pressure to prepare pellets with a thickness of approximately 10 mm and a diameter of approximately 13 mm. The prepared pellets were covered with gold foil, placed in a carbon crucible, and vacuum-sealed using a quartz glass tube. The vacuum-sealed pellets were heated from room temperature to 500 ℃ at a rate of 1.0 ℃ / min using an electric furnace, heat-treated at 500 ℃ for 12 hours, and then cooled to room temperature at a rate of 1.0 ℃ / min to prepare a solid ion conductor compound.

[0224] The composition of the manufactured solid ion conductor compound is (Li 5.69 Cu 0.06 )P(S 4.70 (SO4) 0.05 )Cl 1.25 (The ratio of substituted cations (Cu) was 0.01, and the ratio of substituted anions (SO4) was 0.01.

[0225] Example 2: (Li 5.69+b Cu 0.06 )P(S 4.75+b-a (SO 4 ) a )(Cl 1.25-b (SO 4 ) b ), (SO 4 ) a+b = (SO 4 ) 0.15 , (0 .05 <a<0.15, 0<b<0.15, a+b=0.15)의 제조

[0226] (Li 5.69 Cu 0.06 )P(S 4.60 (SO4) 0.15 )Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting materials was changed to satisfy the composition.

[0227] As shown in Fig. 1b, a solid ion conductor compound of the following composition was obtained by reprecipitating a portion of Cl in the above composition in the form of LiCl.

[0228] The composition of the manufactured solid ion conductor compound is (Li 5.69+b Cu 0.06 )P(S 4.75+b-a (SO4) a )(Cl 1.25-b (SO4) b ), (SO4) a+b = (SO4) 0.15 , (0.05 <a<0.15, 0<b<0.15, a+b=0.15) 이었다.

[0229] Example 3: (Li 5.72 Cu 0.03 )P(S 4.725 (SO 4 ) 0.025 )Cl 1.25 manufacturing

[0230] The intended composition (Li 5.72 Cu 0.03 )P(S 4.725 (SO4) 0.025 )Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting materials was changed to obtain [the desired result].

[0231] The composition of the manufactured solid ion conductor compound is (Li 5.72 Cu 0.03 )PS 4.725(SO4) 0.025 Cl 1.25 (The ratio of substituted cations (Cu) was 0.005, and the ratio of substituted anions (SO4) was 0.005.)

[0232] Example 4: (Li 5.72 Na 0.03 )P(S 4.725 (SO 4 ) 0.025 )Cl 1.25 manufacturing

[0233] The intended composition (Li 5.72 Na 0.03 )P(S 4.725 (SO4) 0.025 )Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that the stoichiometric mixing ratio of the starting materials was changed to obtain [the desired result].

[0234] The composition of the manufactured solid ion conductor compound is (Li 5.72 Na 0.03 )P(S 4.725 (SO4) 0.025 )Cl 1.25 (The ratio of substituted cations (Na) was 0.005, and the ratio of substituted anions (SO4) was 0.005.)

[0235] Example 5: Li 5.75 P(S 4.725 (SO 4 ) 0.025 )Cl 1.25 manufacturing

[0236] The intended composition Li 5.75 P(S 4.725 (SO4) 0.025 )Cl 1.25A solid ion conductor compound was prepared in the same manner as in Example 1, except that Cu2O was not added and the stoichiometric mixing ratio of the starting materials was changed so that a solid ion conductor compound was obtained.

[0237] The composition of the synthesized solid ion conductor compound is Li 5.75 P(S 4.725 (SO4) 0.025 )Cl 1.25 (The ratio of substituted anions (SO4) was 0.005.)

[0238] Comparative Example 1: Li 5.75 PS 4.75 Cl 1.25 manufacturing

[0239] The intended composition Li 5.75 PS 4.75 Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that Cu2O and Li2SO4 were not added and the stoichiometric mixing ratio of the starting materials was changed so that a solid ion conductor compound was obtained.

[0240] The composition of the synthesized solid ion conductor compound is Li 5.75 PS 4.75 Cl 1.25 It was.

[0241] Comparative Example 2: Li 5.75 P(S 4.72 O 0.03 )Cl 1.25 manufacturing

[0242] The intended composition Li 5.75 P(S 4.72 O 0.03 )Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that Li2O was added without adding Cu2O and Li2SO4 and the stoichiometric mixing ratio of the starting materials was changed.

[0243] The composition of the synthesized solid ion conductor compound is Li 5.75 P(S 4.72 O 0.03 )Cl 1.25 (The ratio of substituted anions (O) was 0.006.)

[0244] Reference Example 1: (Li 5.69 Cu 0.06 )PS 4.75 Cl 1.25 manufacturing

[0245] The intended composition (Li 5.69 Cu 0.06 )PS 4.75 Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that Li2SO4 was not added and the stoichiometric mixing ratio of the starting materials was changed so that a solid ion conductor compound was obtained.

[0246] The composition of the manufactured solid ion conductor compound is (Li 5.69 Cu 0.06 )PS 4.75 Cl 1.25 (The ratio of substituted cations (Cu) was 0.01.

[0247] Reference Example 2: (Li 5.72 Cu 0.03 )PS 4.75 Cl 1.25 manufacturing

[0248] The intended composition (Li 5.72 Cu 0.03 )PS 4.75 Cl 1.25 A solid ion conductor compound was prepared in the same manner as in Example 1, except that Li2SO4 was not added and the stoichiometric mixing ratio of the starting materials was changed so that a solid ion conductor compound was obtained.

[0249] The composition of the manufactured solid ion conductor compound is (Li 5.72 Cu 0.03 )PS 4.75 Cl1.25 (The ratio of substituted cations (Cu) was 0.005.)

[0250] Example 6: Manufacturing of an all-solid-state secondary battery

[0251] (Anode layer manufacturing)

[0252] LiNi as a positive electrode active material 0.8 Co 0.15 Al 0.05 O2(NCA) was prepared. As a solid electrolyte, the sulfide-based solid electrolyte powder prepared in Example 1 was prepared. As a conductive agent, carbon nanofibers (CNF) were prepared. These materials were mixed in a weight ratio of cathode active material : solid electrolyte : conductive agent = 60 : 35 : 5 to prepare a cathode composite.

[0253] (Preparation of solid electrolyte powder)

[0254] The sulfide-based solid ion conductor compound prepared in Example 1 was ground using an agate mortar and used as a solid electrolyte powder.

[0255] (Cathode layer manufacturing)

[0256] A metal lithium foil with a thickness of 30 μm was prepared as the cathode.

[0257] (Manufacturing of all-solid-state secondary batteries)

[0258] After sequentially stacking a cathode layer, 150 mg of solid electrolyte powder, and 15 mg of anode mixture on a SUS lower electrode, and then placing a SUS upper electrode on the anode mixture to prepare a laminate, the prepared laminate is 4 ton / cm² 2 It was pressed for 2 minutes under pressure. Subsequently, a solid-state secondary battery was prepared by applying a torque of 4 N·m to the pressed laminate using a torque wrench.

[0259] Examples 7 to 10

[0260] An all-solid-state secondary battery was manufactured in the same manner as in Example 6, except that the solid electrolyte powders manufactured in Examples 2 to 5 were used instead of the solid electrolyte powder manufactured in Example 1.

[0261] Comparative Example 2

[0262] All-solid-state secondary batteries were manufactured in the same manner as in Example 6, except that the solid electrolyte powder prepared in Comparative Example 1 was used instead of the solid electrolyte powder prepared in Example 1.

[0263] Evaluation Example 1: X-ray Diffraction Experiment

[0264] The solid ion conductor compounds prepared in Examples 1 to 5 and Reference Examples 1 to 2 were ground into powder using an agate mortar, and the powder XRD spectra were measured. A portion of the results is shown in Figures 1a to 1c. Cu Kα radiation was used for the XRD spectrum measurement. It was confirmed that the solid ion conductor compounds of Examples 1 to 5 and Reference Example 1 belong to the F-23m space group and have a structure belonging to the cubic crystal system, and are argyrodite-type sulfides having an argyrodite-type crystal structure. Figure 1b is a partial enlarged view of Figure 1a, and Figure 1c is a partial enlarged view of Figure 1b, and is a diagram comparing the peak positions of the solid ion conductor compounds of Example 2 and Reference Example 1.

[0265] In Figures 1a and 1b, a peak corresponding to the LiCl phase was observed in the solid ion conductor compound of Example 2 near a diffraction angle 2θ=35°. In addition, no peaks due to impurities containing SO4 were observed.

[0266] Therefore, the peak attributed to the LiCl phase was determined to be a peak appearing in the solid ion conductor compound of Example 2, caused by the reprecipitation of some Cl in the form of LiCl by substituting SO4 at the S (4c) site and / or Cl (4a) site, excluding the P (4b) site and S (16c) site of the tetrahedral PS4 group contained in the azirodite-type crystal structure. Thus, it was confirmed that SO4 was substituted at the S (4c) site and / or Cl (4a) site in the solid ion conductor compound of Example 2. The Cl (4a) site is a site where S exists before Cl is substituted.

[0267] As shown in Fig. 1c, the solid ion conductor compound of Example 2 exhibited a first peak at a diffraction angle 2θ=30.14° and a second peak at a diffraction angle 2θ=31.52°.

[0268] In addition, as shown in Fig. 1c, the solid ion conductor compound of Reference Example 1 (having the same composition as the solid ion conductor compound of Example 2 except that SO4 is substituted with S) exhibited a third peak at a diffraction angle 2θ = 30.18° and a fourth peak at a diffraction angle 2θ = 31.56°. Thus, it was confirmed that the first and second peaks of the solid ion conductor compound of Example 2 were downshifted by 0.04° to a lower angle, respectively, compared to the third and fourth peaks of the solid ion conductor compound of Reference Example 1.

[0269] This downshift was determined to be due to the increase in the distance between adjacent planes (e.g., d spacing) of the crystal lattice caused by substituting some of the S in the solid ion conductor compound of Example 2 with SO4, which has a larger ionic radius than S.

[0270] Evaluation Example 2: Ionic Conductivity Measurement

[0271] After preparing a powder by grinding the solid ion conductor compounds prepared in Examples 1 to 5 and Comparative Example 1 using an agate mortar, 200 mg of the powder was 4 ton / cm² 2 A pellet specimen with a thickness of approximately 0.101 mm and a diameter of approximately 13 mm was prepared by pressing with a pressure of 2 minutes. A symmetry cell was prepared by placing indium (In) electrodes with a thickness of 50 µm and a diameter of 13 mm on each side of the prepared specimen. The preparation of the symmetry cell was carried out in a glover box under an Ar atmosphere.

[0272] The impedance of the pellet was measured using the 2-probe method with an impedance analyzer (Material Mates 7260 impedance analyzer) for specimens with indium electrodes placed on both sides. The frequency range was 0.1 Hz to 1 MHz, and the amplitude voltage was 10 mV. Measurements were taken at 25°C in an Ar atmosphere. The resistance value was determined from the arc of the Nyquist plot of the impedance measurement results, and the ionic conductivity was calculated by considering the area and thickness of the specimen.

[0273] The measurement results are shown in Table 1 below.

[0274] Ionic conductivity at room temperature (25℃) [mS / cm] Example 1 4.2 Example 2 2.3 Example 3 2.8 Example 4 3.2 Example 5 3.7 Comparative Example 1 2.2 Comparative Example 2 2.8

[0275] As shown in Table 1, the solid ion conductor compounds of Examples 1 to 5 exhibited high ion conductivity of 2.3 mS / cm or higher at room temperature.

[0276] The solid ion conductor compounds of Examples 1 to 5 exhibited improved ion conductivity compared to the solid ion conductor compound of Comparative Example 1.

[0277] The solid ion conductor compound of Example 5 has a corresponding composition, but exhibited improved ion conductivity compared to the solid ion conductor compound of Comparative Example 2, in which O is substituted instead of SO4. In the solid ion conductor compound of Example 5, oxygen ions (O 2- Sulfate ions having an increased ionic radius compared to (SO4, ionic radius of 0.140 nm) 2- It was determined that the crystal structure distortion, etc., provided enhanced ionic conductivity through substitution (ionic radius of 0.147 nm).

[0278] Although the ionic conductivity of the solid ionic conductor compound of Example 2 is lower than that of the solid ionic conductor compound of Comparative Example 2, this reduced ionic conductivity was determined to be due to the additional substitution of Cu in addition to SO4, and the high content of these substitutions. For example, Examples 1 and 3, which have low substitution content of Cu and SO4, showed ionic conductivity equal to or greater than that of Comparative Example 2.

[0279] Evaluation Example 3: Atmospheric Stability Evaluation

[0280] The solid ion conductor compounds prepared in Examples 1 and 2 and Comparative Example 1 were ground into powder using an agate mortar. The prepared powder was then stored for 10 days in a dry room with an air atmosphere having a dew point of less than -60°C, removed, and the change in ion conductivity was measured. The change in ion conductivity was calculated using the ion conductivity retention rate of Equation 1 below. The measurement results are shown in Table 2 below. The initial ion conductivity is the ion conductivity of the prepared powder before storage in the dry room. The ion conductivity was measured under the same conditions and using the same method as in Evaluation Example 2.

[0281] <Mathematical Formula 1>

[0282] Ionic conductivity retention rate = [Ionic conductivity of solid ion-conducting compound after 10 days / Ionic conductivity of solid ion-conducting compound at initial] × 100

[0283] Ion conductivity retention rate [%] Example 1 81.2 Example 2 83.2 Comparative Example 1 65.6

[0284] As shown in Table 2, the solid ion conductor compounds of Examples 1 and 2 exhibited an improved ion conductivity retention rate compared to the solid ion conductor compound of Comparative Example 1.

[0285] The solid ion conductor compounds of Examples 1 and 2 showed improved atmospheric stability or oxidation stability compared to the solid ion conductor compound of Comparative Example 1.

[0286] Evaluation Example 4: Charge / Discharge Test, Interface Stability Evaluation

[0287] The charge-discharge characteristics of the all-solid-state secondary batteries prepared in Example 6 and Comparative Example 2 were evaluated by the following charge-discharge test. The charge-discharge test was performed by placing the all-solid-state secondary batteries in a chamber at 45°C.

[0288] 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 and the current value reached 0.05C. Subsequently, discharge was performed with a constant current of 0.1C until the battery voltage reached 2.5V.

[0289] The discharge capacity of the first cycle was set as the standard capacity.

[0290] The second cycle involved charging for 50 hours at a constant current of 0.1C and a constant voltage of 4.25V until the battery voltage reached 4.25V. Subsequently, the battery was discharged at a constant current of 0.1C until the battery voltage reached 2.5V.

[0291] The discharge capacity of the second cycle was set as the retention capacity.

[0292] The third cycle was charged with a constant current of 0.1C and a constant voltage of 4.25V until the battery voltage reached 4.25V and the current value reached 0.05C. Subsequently, discharge was performed with a constant current of 0.1C until the battery voltage reached 2.5V.

[0293] The discharge capacity of the third cycle was set as the recovery capacity.

[0294] After the charging and discharging steps in each cycle, a rest period of 10 minutes was allowed.

[0295] The capacity recovery rate and capacity retention rate after high-temperature storage of the all-solid-state secondary batteries prepared in Examples 6 to 7 and Comparative Example 2 are shown in Table 3 below.

[0296] The capacity retention rate and capacity recovery rate after high-temperature storage are calculated from the following mathematical formulas 2 and 3.

[0297] <Mathematical Formula 2>

[0298] Retention Capacity Ratio (%) = [Retention Capacity / Standard Capacity] × 100

[0299] <Mathematical Formula 3>

[0300] Recovery Dose Ratio (%) = [Recovery Dose / Standard Dose] × 100

[0301] Retention capacity ratio [%] Recovery dose ratio [%] Example 6 91.4 80.7 Example 7 88.8 73.1 Comparative Example 2 86.9 69.7

[0302] As shown in Table 3, the all-solid-state secondary batteries of Examples 6 and 7 exhibited improved retention capacity ratio and recovery capacity ratio after being left at high temperature for a long time in a charged state compared to the all-solid-state secondary battery of Comparative Example 2.

[0303] The all-solid-state secondary batteries of Examples 6 and 7 showed improved stability (e.g., oxidation resistance) with respect to lithium metal compared to the all-solid-state secondary battery of Comparative Example 2.

Claims

Claim 1 A solid ion conductor compound represented by the following chemical formula 1 and having an azyrodite-type crystal structure: <Chemical Formula 1>Li x M1 v PS y M2 w M3 z In the above formula, M1 is one or more metallic elements other than Li selected from groups 1 to 15 of the periodic table, and M2 is SO n And, M3 is an element selected from Group 17 of the periodic table, 4≤x≤8, 0≤v<1, 3≤y≤7, 0 <w<2, 0≤z≤2, 및 1.5≤n≤5이다. Claim 2 In claim 1, 0 ≤ v / (x+v) < 0.2, and 0 <w / (y+w)<0.2인, 고체이온전도체 화합물. Claim 3 In claim 1, the SO n A solid ion-conducting compound that is S4O6, S3O6, S2O3, S2O4, S2O5, S2O6, S2O7, S2O8, SO4, SO5, or a combination thereof. Claim 4 In claim 1, 0 ≤ v / (x+v) < 0.08, and 0 <w / (y+w)<0.08인, 고체이온전도체 화합물. Claim 5 A solid ion-conducting compound according to claim 1, wherein M1 comprises Na, K, Mg, Ag, Cu, Hf, In, Ti, Pb, Sb, Fe, Zr, Zn, Cr, B, Sn, Ge, Si, Zr, Ta, Nb, V, Ga, Al, As, or a combination thereof. Claim 6 A solid ion-conducting compound according to claim 1, wherein M1 comprises Na, K, Mg, Ag, Cu, or a combination thereof. Claim 7 In claim 1, the solid ion conductor compound in which M3 comprises F, Cl, Br, I, or a combination thereof. Claim 8 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is a solid ion conductor compound represented by the following Chemical Formula 2: <Chemical Formula 2>Li 7-m×v-z M1 v PS 6-w-z M2 w M3 z In the above formula, M1 is one or more metallic elements other than Li selected from groups 1 to 15 of the periodic table, m is the oxidation number of M1, and M2 is SO n and, M3 is an element selected from Group 17 of the periodic table, 0≤v<1, 0 <w<2, 0≤z≤2, 1.5≤n≤5, 및 1≤m≤2이다. Claim 9 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following Chemical Formulas 3 to 4, a solid ion conductor compound: <Chemical Formula 3> (Li 1-d M1 d ) a P(S 1-e M2 e ) b M3 c <Chemical Formula 4>(Li 1-d M1 d ) a Li fc P(S 1+fc-e M2 e ) b (M3 1-f M2 f ) c In the above formulas, M1 is Na, K, Mg, Ag, Cu, Hf, In, Ti, Pb, Sb, Fe, Zr, Zn, Cr, B, Sn, Ge, Si, Zr, Ta, Nb, V, Ga, Al, As, or a combination thereof, M2 is SO4, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <d≤0.08, 0<e≤0.08, 0<f≤0.08, 0<e+f≤0.08이다. Claim 10 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following Chemical Formulas 5 to 6, a solid ion conductor compound: <Chemical Formula 5> (Li 1-d M1 d ) a P(S 1-e (SO4) e ) b M3 c <Chemical Formula 6>(Li 1-d M1 d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c M1 is Na, K, Mg, Ag, Cu, or a combination thereof, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <d<0.08, 0<e<0.08, 0<f<0.08, 0<e+f<0.08이다. Claim 11 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following Chemical Formulas 5a to 6e, a solid ion conductor compound: <Chemical Formula 5a> (Li 1-d Na d ) a P(S 1-e (SO4) e ) b M3 c <Chemical Formula 5b>(Li 1-d K d ) a P(S 1-e (SO4) e ) b M3 c <Chemical Formula 5c>(Li 1-d Mg d ) a P(S 1-e (SO4) e ) b M3 c <Chemical Formula 5d>(Li 1-d Ag d ) a P(S 1-e (SO4) e ) b M3 c <Chemical Formula 5e>(Li 1-d Cu d ) a P(S 1-e (SO4) e ) b M3 c <Chemical Formula 6a>(Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c <Chemical Formula 6b>(Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c <Chemical Formula 6c>(Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c <Chemical Formula 6d>(Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c <Chemical Formula 6e>(Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c In the above equations, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <d≤0.06, 0<e≤0.06, 0<f≤0.06, 0<e+f≤0.06이다. Claim 12 In claim 1, the solid ion conductor compound represented by the above chemical formula 1 is represented by the following chemical formulas, the solid ion conductor compound: (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Cu d ) a P(S 1-e (SO4) e ) b I c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Cu d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Na d ) a P(S 1-e (SO4) e ) b I c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Na d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c , (Li 1-d K d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d K d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d K d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d K d ) a P(S 1-e (SO4) e ) b I c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d K d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c , (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Mg d ) a P(S 1-e (SO4) e ) b I c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Mg d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b F c , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b Cl c , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b Br c , (Li 1-d Ag d ) a P(S 1-e (SO4) e ) b I c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , (Li 1-d Ag d ) a Li fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c , in the above equations, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e<0.06, 0<f<0.06, 0<e+f<0.06이다. Claim 13 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following Chemical Formula 7, a solid ion conductor compound: <Chemical Formula 7>Li 7-p×v-u-z M4 v M5 u PS 6-w-z M2 w M3 z In the above formula, M4 is a metallic element selected from groups 2 to 15 of the periodic table, p is the oxidation number of M4, M5 is a metallic element other than Li selected from group 1 of the periodic table and is a monovalent cation, and M2 is SO n and, M3 is an element selected from Group 17 of the periodic table, 0≤v<1, 0≤u<1, 0 <w<2, 0≤z≤2, 1.5≤n≤5, 및 1≤p≤2이다. Claim 14 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is a solid ion conductor compound represented by the following Chemical Formula 8: <Chemical Formula 8>Li 7-z PS 6-w-z M2 w M3 z In the above equation, M2 is SO n and, M3 is an element selected from Group 17 of the periodic table, and 0 <w<2, 0≤z≤2, 및 1.5≤n≤5이다. Claim 15 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following Chemical Formulas 9 to 10, a solid ion conductor compound: <Chemical Formula 9>Li a+fc P(S 1+fc-e M2 e ) b (M3 1-f M2 f ) c <Chemical Formula 10>Li a P(S 1-e M2 e ) b M3 c In the above equations, M2 is SO4, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e≤0.08, 0<f≤0.08, 0<e+f≤0.08이다. Claim 16 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following Chemical Formulas 11 to 12, a solid ion conductor compound: <Chemical Formula 11>Li a+fc P(S 1+fc-e (SO4) e ) b (M3 1-f (SO4) f ) c <Chemical Formula 12>Li a P(S 1-e (SO4) e ) b M3 c In the above equations, M3 is an element selected from Group 17 of the periodic table, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e<0.08, 0<f<0.08, 0<e+f<0.08이다. Claim 17 In claim 1, the solid ion conductor compound represented by Chemical Formula 1 is represented by the following chemical formulas, solid ion conductor compound:Li a+fc P(S 1+fc-e (SO4) e ) b (F 1-f (SO4) f ) c , Li a+fc P(S 1+fc-e (SO4) e ) b (Cl 1-f (SO4) f ) c , Li a+fc P(S 1+fc-e (SO4) e ) b (Br 1-f (SO4) f ) c , Li a+fc P(S 1+fc-e (SO4) e ) b (I 1-f (SO4) f ) c , Li a P(S 1-e (SO4) e ) b F c , Li a P(S 1-e (SO4) e ) b Cl c , Li a P(S 1-e (SO4) e ) b Br c , Li a P(S 1-e (SO4) e ) b I c , in the above equations, 5≤a≤7, 4≤b≤6, 0≤c≤2, and 0 <e<0.06, 0<f<0.06, 0<e+f<0.06이다. Claim 18 A solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by the above chemical formula 1 has an ion conductivity of 1.0 mS / cm or more at 25°C. Claim 19 The solid ion conductor compound represented by Chemical Formula 1, wherein the solid ion conductor compound has an ion conductivity retention rate of 70% or more after 10 days under dry conditions in an air atmosphere having a dew point of less than -60°C, and the ion conductivity retention rate is represented by the following Mathematical Formula 1. <Mathical Formula 1> Ion conductivity retention rate = [Ion conductivity of solid ion conductor compound after 10 days / Ion conductivity of solid ion conductor compound at the beginning] × 100 Claim 20 A solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by the above chemical formula 1 belongs to a cubic crystal system. Claim 21 A solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by the above chemical formula 1 belongs to the F-43m space group. Claim 22 A solid ion conductor compound according to claim 1, wherein the solid ion conductor compound represented by Formula 1 includes a first peak at a diffraction angle 2θ = 30.1°±0.5° and a second peak at a diffraction angle 2θ = 31.5°±0.5° in an XRD spectrum using CuKα rays, and a compound having the same composition as the solid ion conductor compound represented by Formula 1, except that M2 is changed to S, includes a third peak at a diffraction angle 2θ = 30.1°±0.5° and a fourth peak at a diffraction angle 2θ = 31.5°±0.5° in an XRD spectrum using CuKα rays, wherein the positions of the first peak and the second peak are each downshifted by at least 0.01° relative to the third peak and the fourth peak. Claim 23 A solid ion conductor compound according to claim 1, further comprising a peak corresponding to LiM3 reprecipitated by M2 at a diffraction angle 2θ=35.0°±1.0° in an XRD spectrum using CuKα lines. Claim 24 A solid electrolyte comprising a solid ion-conducting compound according to any one of claims 1 to 23. Claim 25 An electrochemical cell comprising: an anode layer including an anode active material layer; a cathode layer including a cathode active material layer; and an electrolyte layer disposed between the anode layer and the cathode layer, wherein one or more selected from the anode active material layer and the electrolyte layer comprises a solid ion conductor compound according to any one of claims 1 to 23. Claim 26 In claim 25, the electrochemical cell is an all-solid-state secondary battery. Claim 27 An electrochemical cell according to claim 25, wherein the cathode active material layer comprises a cathode active material and a binder, and the cathode active material is a mixture of amorphous carbon and one or more selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn) and zinc (Zn). Claim 28 An electrochemical cell according to claim 25, wherein the cathode layer further comprises a cathode current collector and further comprises a metal layer disposed between the cathode current collector and the cathode active material layer, and the metal layer comprises lithium or a lithium alloy. Claim 29 A compound containing lithium; one or more compounds containing a metal element other than Li selected from Groups 1 to 15 of the periodic table; a compound containing phosphorus (P); SO n A method for preparing a solid ion conductor compound comprising: a step of providing a mixture by contacting a compound containing (1.5≤n≤5); and a compound containing an element of Group 17 of the periodic table; and a step of providing a solid ion conductor compound by heat-treating the mixture in an inert atmosphere. Claim 30 A method for manufacturing a solid ion conductor compound according to claim 29, wherein the heat treatment is performed at a temperature of 400°C to 600°C for 1 to 36 hours.

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