KR102180352B1 - Sulfide glass ceramic, process for producing the same, and all-solid secondary battery containing the solid electrolyte - Google Patents

Abstract

The present invention relates to a sulfide-based glass ceramic, a method for manufacturing the same, and an all-solid secondary battery containing the same as a solid electrolyte, and the sulfide-based glass ceramic of the present invention may be represented by the following Formula 1. <Formula 1>: 80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS _{2 In} Formula 1, x is 1 to 10. According to the present invention, by using a sulfide-based glass ceramic solid electrolyte to which SnS ₂ is added, it is possible to provide a secondary battery capable of maintaining a cyclic lithium ion conductivity while exhibiting high electrochemical stability compared to a conventional secondary battery. .

Description

Sulfide glass ceramic, process for producing the same, and all-solid secondary battery containing the solid electrolyte}

The present invention relates to a solid electrolyte, and more particularly, to a sulfide-based glass ceramic solid electrolyte and a method of manufacturing the same.

In recent years, as small electronic devices and electric vehicles are widely spread, the demand for secondary batteries having high energy density is gradually increasing. Currently, lithium secondary batteries using lithium ions are widely used as secondary batteries.

Since the conventional lithium secondary battery uses a flammable liquid electrolyte, strict packaging is required, and accordingly, it is difficult to increase the energy density above a certain level. In addition, a lithium secondary battery using a liquid electrolyte has a very high risk of ignition and explosion due to its large volume.

To overcome this, research on an all-solid-state secondary battery in which a flammable liquid electrolyte is replaced with a safer inorganic ceramic material has been attempted. All-solid secondary batteries are attracting attention as next-generation secondary batteries because of their high energy density and safety. In addition, since the inorganic solid electrolyte is stable without being decomposed over a wide voltage range, it is possible to utilize a high voltage electrode material that was difficult to use in the existing liquid electrolyte.

On the other hand, solid electrolytes are divided into oxide-based and sulfide-based, and sulfide-based solid electrolytes exhibit higher ionic conductivity than oxide-based. Among the sulfide-based solid electrolytes, Li ₂ SP ₂ S ₅ solid electrolyte is the most representative material of next-generation materials with high ionic conductivity. However, Li ₂ SP ₂ S ₅ solid electrolyte, Li ₂ S and free sulfur, which are added in excess to improve ionic conductivity, remain after synthesis, and side reactions between Li metals, reactivity with moisture, and interfaces with active materials. When the reactivity is increased and applied to a battery, there is a problem in that chemical and electrochemical stability are lowered.

Republic of Korea Patent Publication No. 10-2015-0014185

The problem to be solved by the present invention is to provide a glass ceramic having excellent chemical stability compared to Li ₂ SP ₂ S ₅ glass ceramic, and an all-solid secondary battery containing the same as a solid electrolyte.

In order to achieve the above object, an aspect of the present invention provides a sulfide-based glass ceramic. The sulfide-based glass ceramic may be represented by Chemical Formula 1. <Formula 1> 80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS _{2 In} Formula 1, x may be 1 to 10. The x may be 3 to 7. The x may be 4 to 6. The glass ceramic may have a composition of 80Li ₂ S·15P ₂ S _5· 10SnS ₂ .

In order to achieve the above object, another aspect of the present invention provides a method of manufacturing a sulfide-based glass ceramic. The sulfide-based glass ceramic manufacturing method is mechanically pulverized a mixed powder containing Li ₂ S, P ₂ S ₂ and SnS ₂ in a molar ratio of 80:(20-x):(2x) (1≦x≦10) It may include forming an amorphous powder and forming a glass ceramic solid electrolyte by heat-treating the amorphous powder. The x may be 4 to 6. The mechanical pulverization may be performed for 20 to 55 hours at a rotational speed of 300 rpm to 520 rpm. The heat treatment may be performed in the range of 240°C to 280°C.

In order to achieve the above object, another aspect of the present invention provides a sulfide-based all-solid battery. The sulfide-based all-solid-state battery includes a positive electrode, a solid electrolyte layer, and a negative electrode sequentially stacked, and the solid electrolyte layer may include the sulfide-based glass ceramic particles of claim 1. The negative electrode may be a lithium metal.

According to the present invention, by using a sulfide-based glass ceramic solid electrolyte to which SnS ₂ is added, it is possible to provide a secondary battery capable of maintaining a cyclic lithium ion conductivity while exhibiting high electrochemical stability compared to a conventional secondary battery. .

The technical effects of the present invention are not limited to those mentioned above, and other technical effects that are not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a schematic cross-sectional view of an all-solid-state battery according to an embodiment of the present invention.
2 is a graph showing the results of differential thermal analysis (DTA) for amorphous powder obtained during the manufacturing process of the solid electrolyte according to Preparation Examples 1 to 5 and Comparative Example 1.
3 is a graph showing Raman analysis results of solid electrolytes according to Preparation Examples 1 to 5 and Comparative Examples.
FIG. 4 is a graph showing X-ray diffraction (XRD) results of solid electrolytes according to Preparation Examples 1 to 5 and Comparative Example 1. FIG.
5 is a graph showing ionic conductivity at room temperature (25° C.) of solid electrolytes according to Preparation Examples 1-5 and Comparative Examples.
6A and 6B show cyclic voltammograms (CV) of the solid electrolyte according to Preparation Examples 1, 3, 4, and 5.
7 shows cyclic voltammograms (CV) of the solid electrolyte according to Preparation Example 1.
8A is a graph showing charge and discharge curves of an all-solid secondary battery using the solid electrolyte of Comparative Example 1 and Preparation Example 1, and FIG. 8B is a coulomb for the all-solid secondary battery using the solid electrolyte of Preparation Example 1 of the present invention. It is a graph showing the efficiency (Coulomb efficiency (%)).
9 is a photoelectron analysis (X-ray photoelectron spectroscopy, XPS) results of the solid electrolyte before and after driving the all-solid secondary battery using the solid electrolyte of Preparation Example 1 and Comparative Example 1.

Hereinafter, preferred embodiments according to the present invention will be described in more detail with reference to the accompanying drawings in order to describe the present invention in more detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. In the drawings, when a layer is said to be “on” another layer or substrate, it may be formed directly on the other layer or substrate, or a third layer may be interposed therebetween.

In the present specification, "glass ceramic" is a material having an amorphous phase and one or more crystalline phases, and is used in the same concept as crystallized glass.

Sulfide glass ceramic

The sulfide-based glass ceramic of the present invention may contain lithium sulfide, phosphorus sulfide, and tin sulfide. The lithium sulfide may be Li ₂ S, the phosphorus sulfide may be P ₂ S ₅ and the tin sulfide may be SnS ₂ . The sulfide-based glass ceramic may be obtained by adding tin sulfide (SnS ₂ ) to a sulfide (Li ₂ SP ₂ S ₅ ) composed of lithium sulfide (Li ₂ S) and phosphorus sulfide (P ₂ S ₅ ).

The sulfide-based glass ceramic may have a thio-LISICON III crystal phase. Such, the sulfide-based glass ceramic can be used as a solid electrolyte for an all-solid secondary battery (all-solid secondary battery).

In the sulfide-based glass ceramic, when the tin sulfide (SnS ₂ ) is added to the sulfide (Li ₂ SP ₂ S ₅ ), the pentavalent phosphorus ion (P ⁵⁺ ) is tetravalent in the process of synthesizing the sulfide-based glass ceramic. It can be mainly substituted with tin ions (Sn ⁴⁺ ). This eliminates the problem caused by the remaining amount of Li ₂ S during the synthesis process of the existing solid electrolyte Li ₂ SP ₂ S ₅ material, for example, 80Li ₂ S20P ₂ S ₂ or 70Li ₂ S30P ₂ S ₂ Or you can reduce it.

Specifically, by the hard and soft acids and bases, sulfur (S) forms a stronger bond with tin (Sn), which is a weak base than phosphorus (P), which is a strong acid, and thus, PS ₄ ^3- Substitution of SnS ₄ ^4- is mainly performed. Accordingly, since the amount of Li ₂ S remaining can be significantly reduced, problems such as generation of side reactions with lithium metal having a large capacity, reactivity with moisture, and interfacial reactivity with active materials can be eliminated or reduced. These sulfide-based glass ceramics are solid electrolytes for all-solid secondary batteries, and exhibit excellent chemical and electrochemical stability to further improve cell performance.

The sulfide-based glass ceramic may be represented by Formula 1 below.

<Formula 1>

80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ (1≤ x ≤10)

In Formula 1, x may be 1 to 10, specifically, 3 to 7, more specifically, 4 to 6, for example, x may be 5.

As described above, the sulfide-based glass ceramic exhibits excellent chemical stability by reducing or removing the amount of Li ₂ S remaining in the glass ceramic, while maintaining high lithium ion conductivity. Accordingly, it is possible to use a metal having a large capacity, such as Li metal, as an anode of an all-solid secondary battery using this as a solid electrolyte. The sulfide-based glass ceramic for this may have a composition of 80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ (4≦x≦6). As an example, the sulfide-based glass ceramic may have a composition of 80Li ₂ S15P ₂ S ₅ 10SnS ₂ .

As a method of manufacturing the sulfide-based glass ceramic, first, a mixed powder of lithium sulfide, phosphorus sulfide, and tin sulfide may be mechanically pulverized to form an amorphous powder (S10). The mixed powder may be obtained by mixing the lithium sulfide, phosphorus sulfide, and tin sulfide at a molar ratio of 80:(20-x):(2x) (1≦x≦10). The range of x may be the same as the range described above. As an example, the mixed powder may be a mixture of lithium sulfide (Li ₂ S), phosphorus sulfide (P ₂ S ₂ ), and tin sulfide (SnS ₂ ) at a molar ratio of 80:15:10.

The mechanical pulverization may be, for example, synthesizing an amorphous solid electrolyte powder from the mixed powder by ball-milling. The mechanical pulverization may be performed, for example, at a rotation speed of 300 rpm to 520 rpm, specifically, 300 rpm to 400 rpm, for 20 to 55 hours, specifically, 30 to 50 hours. The ball milling may be performed dry, or may be performed wet using an organic solvent such as a solvent, for example, heptane.

The amorphous powder may be subjected to crystallization heat treatment to form a glass-ceramic solid electrolyte powder (S20). The heat treatment temperature may be performed at a temperature equal to or higher than the crystallization temperature Tc of the amorphous powder. For example, the heat treatment temperature may be 240 ℃ to 280 ℃. The heat treatment may be performed in an inert gas atmosphere such as argon gas.

All solid battery

1 is a schematic cross-sectional view of an all-solid-state battery according to an embodiment of the present invention.

Referring to FIG. 1, the all-solid-state battery 100 is a sulfide-based all-solid-state battery, and may include a positive electrode 10, a solid electrolyte layer 50, and a negative electrode 30 sequentially stacked. Here, the positive electrode 10 may be a mixed layer of a positive electrode active material, a solid electrolyte, and a conductive material. The positive electrode active material is Li _1-x MPO ₄ (M=Fe, Mn or Ni, 0≤x≤1), Li _1-x MnO ₂ (0≤x≤1), LiCoO ₂ , Li _1-x NiaMnbCocO ₂ ( 0≦ _x ≦1, a+b+c≦ ₁ ) and Li _1-x NiaCobAlc (0≦x≦1, a+b+c≦1) may be one or more selected from the group consisting of, but is not limited thereto. . The solid electrolyte may be a sulfide-based glass ceramic particle represented by Formula 1 to be described later, or a known solid electrolyte may be used.

The solid electrolyte layer 50 may be a layer in which sulfide-based glass ceramic particles are stacked. As described above, the sulfide-based glass ceramic particles are glass ceramic particles containing lithium sulfide, phosphorus sulfide, and tin sulfide. The lithium sulfide may be Li ₂ S, the phosphorus sulfide may be P ₂ S ₅ , and the tin sulfide may be SnS ₂ . In addition, the sulfide-based glass ceramic may be represented by Formula 1 below.

<Formula 1>

80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ (1≤ x ≤10)

In Formula 1, x may be 1 to 10, specifically, 3 to 7, more specifically, 4 to 6, for example, x may be 5.

The negative electrode 30 may be a lithium metal.

Each layer of the anode 10, the solid electrolyte layer 50, and the cathode 30 forms a slurry containing the corresponding materials, and then the slurry is sequentially stacked by tape casting, screen printing, or electrostatic spraying, or It can be formed by pressing the powder containing particles. Thereafter, after the lamination is completed, the pressing may be performed by one or more methods selected from the group consisting of a hot press, a roll press, and a warm hydrostatic press (WIP).

Hereinafter, preferred experimental examples according to the present invention will be described in more detail with reference to the accompanying drawings in order to describe the present invention in more detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.

<Production Example 1: Glass ceramic solid electrolyte powder (80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ x=5 manufacturing>

In the presence of argon gas in a glove box, Li ₂ S, P ₂ S ₅ and SnS ₂ were weighed at a molar ratio of 80: 15:10, respectively, to prepare a mixed powder uniformly mixed, and then transferred to an alumina pot having a volume of 100 ml. Zirconia balls (diameter: 3 mm), 120 g, 3 g, and 24 g of heptane were added, respectively, and then mechanically pulverized sufficiently for 48 hours at a rotation speed of 370 rpm to synthesize an amorphous powder. Thereafter, a glass-ceramic solid electrolyte powder was prepared through a heat treatment process for 3 hours under an argon atmosphere at a temperature of 260°C.

<Production Examples 2 to 5: Glass ceramic solid electrolyte powder (80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ x=1,3,7,10 manufacturing>

Glass ceramic solid electrolytes of other Preparation Examples were prepared in the same manner as Preparation Example 1, except that the mixing ratio and heat treatment temperature of Li ₂ S, P ₂ S ₅ and SnS _{2 in} the mixed powder were different as shown in Table 1 below. .

<Comparative Example 1: Glass ceramic solid electrolyte powder (80Li ₂ S20P ₂ S ₅ ) Manufacturing>

Glass ceramics solid electrolyte powder was prepared in the same manner as in Preparation Example 1, except that Li ₂ S and P ₂ S ₅ were mixed in a molar ratio of 80:20 as the mixed powder, and the heat treatment temperature was 234°C. Was prepared.

<Comparative Example 2: Glass ceramic solid electrolyte powder (75Li ₂ S25P ₂ S ₅ ) Manufacturing>

Glass ceramics solid electrolyte powder was prepared in the same manner as in Preparation Example 1, except that Li ₂ S and P ₂ S ₅ were mixed at a molar ratio of 75:25 as the mixed powder and the heat treatment temperature was 240°C. I did.

Table 1 below shows the composition or ?t amount and heat treatment temperature of the glass ceramics according to Preparation Examples 1 to 5 and Comparative Examples 1 and 2.

80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ Heat treatment temperature x Li ₂ S P ₂ S ₅ SnS ₂ 260℃ Manufacturing Example 1 5 80 15 10 252℃ Manufacturing Example 2 One 80 19 2 237℃ Manufacturing Example 3 3 80 17 6 241℃ Manufacturing Example 4 7 80 13 14 264℃ Manufacturing Example 5 10 80 10 20 274℃ Comparative Example 1 0 80 20 - 234℃ Comparative Example 2 - 75 25 - 240℃

2 is a graph showing the results of differential thermal analysis (DTA) for amorphous powder obtained during the manufacturing process of the solid electrolyte according to Preparation Examples 1 to 5 and Comparative Example 1.

Referring to FIG. 2, crystallization temperatures of amorphous powders having respective compositions in Preparation Examples 1 to 5 and Comparative Example 1 can be confirmed. The crystallization temperature gradually increased as the content of SnS ₂ to be added increased (as the x value of 80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ increased). Among them, since it was confirmed that the crystallization temperature of the amorphous powder obtained during the process of Preparation Example 1 was about 253°C, the crystallization heat treatment in Preparation Example 1 was performed at 260°C, which is a slightly higher temperature. The crystallization heat treatment temperature of the amorphous powder obtained during the manufacturing process of the other Preparation Examples and Comparative Examples was also set higher than the crystallization temperature of FIG. 2.

3 is a graph showing Raman analysis results of solid electrolytes according to Preparation Examples 1 to 5 and Comparative Examples.

Referring to FIG. 3, it can be seen that the intensity of the peak corresponding to PS ₄ ^3- decreases and the intensity of the peak corresponding to SnS ₄ ^4- increases as the amount of SnS ₂ added, that is, the x value increases. From these results, it is interpreted that as the amount of SnS ₂ added, that is, the x value, increases, the degree to which PS ₄ ^3- is substituted with SnS ₄ ^4- increases.

FIG. 4 is a graph showing X-ray diffraction (XRD) results of solid electrolytes according to Preparation Examples 1 to 5 and Comparative Example 1. FIG.

Referring to FIG. 4, in Comparative Example 1, that is, 80Li ₂ S20P ₂ S ₅ , the thio-LISICON II crystal phase is predominantly identified. However, in Preparation Examples 1 to 5, it was confirmed that the crystalline phase of thio-LISICON III appeared as the content of Li ₂ S was fixed and the content of SnS ₂ (x value) was increased. In Preparation Example 4 (x=7) and Preparation Example 5 (x=10), a Li ₄ SnS ₄ crystal phase was further confirmed.

On the other hand, Comparative Example 1, that is, 80Li ₂ S20P _2, but confirmed that in S ₅ the intensity of the peak for the Li ₂ S crystal relatively high, in accordance with the increase of the content (x value) of SnS ₂ Li ₂ for S determined The intensity of the peak decreases, and in Preparation Example 1, Preparation Example 4, and Preparation Example 5 (x=5, 7, 10), it can be seen that the peak for the Li ₂ S crystal disappeared. As such, it can be predicted that the chemical and electrochemical stability of the solid electrolyte will increase as the content of the Li ₂ S crystal is reduced or removed as the content of SnS ₂ (x value) is increased.

5 is a graph showing ionic conductivity at room temperature (25° C.) of solid electrolytes according to Preparation Examples 1-5 and Comparative Examples.

Referring to FIG. 5, when the content (x value) of SnS ₂ is increased, the ionic conductivity tends to decrease. However, Preparation Example 1 (x = 5), 2 (x = 1) and 3 (x = 3) did not significantly decrease the ionic conductivity compared to Comparative Example 1 (80Li ₂ S20P ₂ S ₅ ), Preparation Example 4 ( In the case of x=7), it can be seen that the ionic conductivity was not significantly reduced compared to Comparative Example 2 (75Li ₂ S25P ₂ S ₅ ) having a thio-LISICON II crystal phase. In particular, the ionic conductivity of Preparation Example 1 (x=5) glass ceramic was 6.4×10 ^-4 S/cm, and the ionic conductivity of Comparative Example 2 (75Li ₂ S25P ₂ S ₅ ) (5.0×10 ^-4 S/cm) Compared to, it is excellent.

Referring to FIGS. 4 and 5 together, unlike Preparation Examples 2 and 3 in which a problem due to the remaining Li ₂ S is expected because the peak of Li ₂ S is confirmed, Preparation Examples 1 and 4, in particular, Preparation Example 1 Since the peak of Li ₂ S is not confirmed, it is possible to exert an effect of exhibiting excellent ionic conductivity characteristics while exhibiting high chemical stability.

6A and 6B show cyclic voltammograms (CV) of the solid electrolyte according to Preparation Examples 1, 3, 4, and 5. To this end, a solid electrolyte according to each of Preparation Examples 1, 3, 4 and 5 was used as the working electrode, and a cell using Li metal as the counter electrode was used at room temperature at a rate of -0.5V to 5.0V at a rate of 20 mV s ^-1 . It was scanned by voltage range.

6A and 6B, it can be seen that in Preparation Examples 1 and 3, peak currents are higher than those in Preparation Examples 4 and 5. It is estimated that this is related to the ionic conductivity characteristics in FIG. 5 described above. However, in the case of Preparation Example 3, it can be seen that the current peak value decreases as the cycle is repeated, whereas in Preparation Examples 1 and 4, the current peak value is almost constant. This indicates that the chemical stability of Preparation Examples 1 and 4 is excellent. In addition, Preparation Examples 1 and 4, particularly, Preparation Example 1 of the present invention show that excellent chemical stability can be exhibited even when a lithium metal having a large capacity is used as a negative electrode.

7 shows cyclic voltammograms (CV) of the solid electrolyte according to Preparation Example 1. To this end, the solid electrolyte according to Preparation Example 1 was used as the working electrode, and the cell using Li metal as the counter electrode was scanned in a voltage range of -0.5 V to 5.0 V at a rate of 20 mV s ^-1 at high temperature (600°C). I did it.

Referring to FIG. 7, it can be seen that in the case of Preparation Example 1, even if the cycle is repeated even at a high temperature of about 600° C., the current value is almost constant. This shows that Preparation Example 1 can exhibit excellent chemical stability not only at room temperature but also at high temperature.

<Example of solid battery manufacturing>

The solid electrolyte according to Preparation Example 1 was pelletized to form a solid electrolyte layer. Thereafter, Li(Ni _0.6 CO _0.2 Mn _0.2 )O ₂ , the solid electrolyte according to Preparation Example 1 (80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂ (x=5)), and Super C After mixing at a weight ratio of 70:30:3, the mixture was spread on one of the upper or lower surfaces of the solid electrolyte layer and then pressed to form an anode layer. A solid battery was manufactured by forming a negative electrode layer by compressing lithium metal on the other surface of the upper or lower surface of the solid electrolyte layer.

<Comparative Example of Solid Battery>

A solid battery was manufactured in the same manner as in the above-described solid battery manufacturing example, except that the solid electrolyte of Comparative Example 1 was used instead of the solid electrolyte of Preparation Example 1, and the solid electrolyte of Comparative Example 1 was used as the solid electrolyte of the anode layer I did.

8A is a graph showing charge and discharge curves of all-solid secondary batteries using the solid electrolytes of Comparative Example 1 and Preparation Example 1; In the initial evaluation of charge and discharge capacity, charge and discharge were performed at a current density of 0.05C in a voltage range of 2.8V to 4.25V. 8B is a graph showing the Coulomb efficiency (%) during charging and discharging of 10 cycles for an all-solid secondary battery using the solid electrolyte of Preparation Example 1 of the present invention.

Referring to FIG. 8A, in the case of Preparation Example 1, it was confirmed that the charging capacity was 125mAhg ^-1 and the discharge capacity was 175 mAhg ^-1 , and while the charging and discharging operation was stably performed, Comparative Example 1 was not able to perform the charging and discharging operation. I can. In the case of Preparation Example 1, the Li ₂ S content was decreased by the addition of SnS ₂ to show high stability to the lithium metal as the negative electrode, whereas in Comparative Example 1, the negative electrode was due to the remaining Li ₂ S. It shows that the stability to lithium metal is very low.

Referring to FIG. 8B, Preparation Example 1 shows an excellent Coulomb efficiency (%) of 80% or more, although the discharge capacity decreases as the number of cycles increases.

9 is a photoelectron analysis (X-ray photoelectron spectroscopy, XPS) results of the solid electrolyte before and after driving the all-solid secondary battery using the solid electrolyte of Preparation Example 1 and Comparative Example 1.

Referring to FIG. 9, comparing before and after driving the secondary battery, in the case of Comparative Example 1 (80Li ₂ S20P ₂ S ₅ ), the S2p _1/2 and S2p _y/2 peaks of the PS-Li crystal decreased, and Li ₂ The S2p _1/2 and S2p _y/2 peaks of S were increased. This shows that the solid electrolyte of Comparative Example 1 has an increased content of Li ₂ S, which is not electrochemically stable due to a side reaction with Li metal during the conduction of Li ions when the secondary battery is driven.

On the other hand, in Preparation Example 1 (80Li ₂ S15P ₂ S ₅ 10SnS ₂ ), the peak of Li ₂ S was lower than that of Comparative Example 1, and the peak change exhibited by the crystal of P/Sn-S-Li before and after the reaction with Li metal There were very few. This shows that Preparation Example 1 can exhibit excellent chemical stability by greatly suppressing side reactions with lithium metal having a large capacity due to the addition of SnS ₂ .

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are only presented specific examples to aid understanding, and are not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is apparent to those of ordinary skill in the art that other modified examples based on the technical idea of the present invention may be implemented.

100: all-solid battery 10: positive electrode
50: solid electrolyte layer 30: negative electrode

Claims (10)

A sulfide-based glass ceramic represented by the following formula (1) and having at least one crystalline phase in addition to an amorphous phase:
<Formula 1>
80Li ₂ S(20-x)P ₂ S ₅ (2x)SnS ₂
In Formula 1, x is 1 to 10. The method of claim 1,
Wherein x is 3 to 7, sulfide-based glass ceramic. The method of claim 2,
Wherein x is 4 to 6, sulfide-based glass ceramic. The method of claim 1,
The glass ceramic will have a composition of 80Li ₂ S15P ₂ S ₅ 10SnS ₂ , a sulfide-based glass ceramic. Mechanically grinding the mixed powder containing Li ₂ S, P ₂ S ₅ and SnS ₂ in a molar ratio of 80:(20-x):(2x) (1≦x≦10) to form an amorphous powder; And
A method for manufacturing a sulfide-based glass ceramic comprising the step of heat-treating the amorphous powder in the range of 240°C to 280°C to form the glass ceramic solid electrolyte of claim 1. The method of claim 5,
Wherein x is 4 to 6, sulfide-based glass ceramic manufacturing method. The method of claim 5,
The mechanical pulverization is performed at a rotation speed of 300 rpm to 520 rpm, for 20 to 55 hours, a method for producing a sulfide-based glass ceramic. delete Including a positive electrode, a solid electrolyte layer, and a negative electrode sequentially stacked,
The solid electrolyte layer is a sulfide-based all-solid-state battery comprising the sulfide-based glass ceramic particles of claim 1. The method of claim 9,
The negative electrode is a lithium metal, a sulfide-based all-solid battery.

Images