CN111244534A - Sulfur oxide solid electrolyte, its preparation method and application - Google Patents

Abstract

The invention provides a sulfur oxide solid electrolyte, the sulfur oxide solid electrolyte contains two anions of sulfur and oxygen at the same time, and the general formula of the sulfur oxide solid electrolyte is A _x My S _{z -u} O _u , Preparation methods and applications thereof are also provided. The electrolyte system is prepared by directly oxidizing an existing sulfide solid electrolyte with an oxidant, which includes dry air. The sulfur oxide solid electrolyte of the present invention effectively combines the advantages of high electrical conductivity, excellent mechanical properties and good air and chemical stability of oxide solid electrolytes of sulfide solid electrolytes while avoiding their disadvantages. The sulfur oxide solid electrolyte realizes the operation of the sulfide solid electrolyte in a dry room and the assembly of its all-solid-state battery. The sulfur oxide solid electrolyte provided by the present invention is expected to be applied to the next-generation high specific energy battery, and is applied in practical life in preference to the sulfide solid electrolyte and the oxide solid electrolyte.

Description

Sulfur oxide solid electrolyte, its preparation method and application

technical field

The invention belongs to the field of chemical power sources, in particular to the preparation of a sulfur oxide solid electrolyte and its application in an all-solid-state battery.

Background technique

Most of the current commercial secondary ion batteries use liquid electrolytes to realize the transfer of anions and cations between the positive and negative electrodes. Since the liquid electrolyte contains flammable organic solvents, such batteries have potential safety problems such as electrolyte leakage, poor thermal stability, and battery combustion or even explosion. In order to improve the safety of batteries, people began to use solid electrolytes instead of liquid electrolytes to construct and realize the next generation of all-solid-state batteries with high specific energy and high safety.

Solid electrolytes can be roughly divided into polymer electrolytes, inorganic ceramic electrolytes and composite electrolytes combining the above two. Compared with polymer electrolytes, inorganic ceramic electrolytes have higher room temperature ionic conductivity. Inorganic ceramic electrolytes are further divided into oxide solid electrolytes and sulfide solid electrolytes. Compared with oxide solid electrolyte materials, sulfide solid electrolytes have higher ionic conductivity, better mechanical ductility and flexibility, and can be synthesized at room temperature or low temperature (<500 degrees Celsius) and prepared by cold pressing method Dense electrolyte sheet and composite electrode with positive and negative electrode materials. However, most sulfide solid electrolytes are sensitive to air and easily react with air to generate toxic and harmful hydrogen sulfide gas; and are prone to chemical reactions with high-voltage oxide cathode materials to generate some by-products that hinder ion transport and electron conduction, thereby increasing the The battery is polarized, deteriorating the battery performance; these shortcomings limit the practical application of the existing sulfide solid electrolytes. In contrast, oxide solid electrolytes have better chemical stability to air and to high-voltage oxide cathode materials.

In order to effectively combine the advantages of high electrical conductivity and excellent mechanical properties of sulfide solid electrolytes and high chemical stability of oxide solid electrolytes while avoiding their respective disadvantages, the present invention proposes a preparation of sulfur oxide solid electrolytes and its application in the whole process. applications in solid-state batteries. The sulfur oxide solid electrolyte is prepared by directly oxidizing the existing sulfide solid electrolyte by an oxidant; the preparation method is simple, efficient, and can be mass-produced. The prepared sulfur oxide solid electrolyte has high electrical conductivity and excellent mechanical properties, improves the air and chemical stability of the original sulfide solid electrolyte, and realizes the processing operation of the sulfide electrolyte in the battery dry room and the assembly of the all-solid-state battery. . All-solid-state batteries based on the sulfur oxide solid electrolyte have the advantages of high capacity, low polarization, and long life.

SUMMARY OF THE INVENTION

Therefore, the purpose of the present invention is to overcome the defects in the prior art, and provide a preparation of a sulfur oxide solid electrolyte and its application in an all-solid-state battery.

In order to achieve the above object, a first aspect of the present invention provides a sulfur oxide solid electrolyte, the sulfur oxide solid electrolyte contains two anions of sulfur and oxygen at the same time, and the general formula of the sulfur oxide solid electrolyte is A _x M _y S _{z- u} O _u ; where:

A is a metal ion; preferably, A is selected from one or more of the following: lithium, sodium, potassium, magnesium, calcium, aluminum, zinc;

M is a metal ion and/or a non-metal ion; preferably, M is selected from one or more of the following: lithium, boron, carbon, nitrogen, fluorine, sodium, magnesium, aluminum, silicon, phosphorus, chlorine, potassium, calcium, Scandium, titanium, vanadium, copper, zinc, gallium, germanium, zirconium, arsenic, selenium, bromine, strontium, yttrium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, cadmium, indium, tin, antimony, tellurium, iodine, Tantalum, tungsten, lead, bismuth, lanthanum, cerium, samarium, europium;

S is sulfur, O is oxygen;

The value ranges of x, y, z, and u are respectively 0 to 20 and z>u.

The sulfur oxide solid electrolyte according to the first aspect of the present invention, wherein the sulfur oxide solid electrolyte is obtained by directly oxidizing the sulfide solid electrolyte by an oxidant;

Preferably, the general formula of the sulfide solid electrolyte is A _{x My S z .}

The sulfur oxide solid electrolyte according to the first aspect of the present invention, wherein the oxidant is an oxidizing gas or liquid;

Preferably, the oxidant is selected from one or more of the following: oxygen, dry air, ozone, sulfur dioxide, sulfur trioxide, nitrogen dioxide, dinitrogen tetroxide, carbon monoxide, carbon dioxide, hydrogen peroxide, chloric acid, hypochlorous acid, Nitric acid, sulfuric acid, sulfurous acid, bromic acid, hypobromic acid, iodic acid, hypoiodic acid, metaperiodic acid;

More preferably, the oxidizing agent is selected from oxygen, dry air, ozone, nitric acid, sulfur dioxide, and/or sulfuric acid.

According to the sulfur oxide solid electrolyte according to the first aspect of the present invention, the oxidation degree of the sulfur oxide solid electrolyte is bulk oxidation, step oxidation or surface oxidation.

The sulfur oxide solid electrolyte according to the first aspect of the present invention, wherein the ionic conductivity of the sulfur oxide solid electrolyte is greater than 10 ^-7 S/cm; and/or the electronic conductivity of the sulfur oxide solid electrolyte is less than 10 ^-7 S/cm.

According to the sulfur oxide solid electrolyte according to the first aspect of the present invention, the sulfide electrolyte is preferably selected from one or more of the following: Li ₁₀ GeP ₂ S ₁₂ , Li ₇ GePS ₈ , Li _9.54 Si _1.74 P _1.44 S _11.7 Cl _0.3 , Li ₆ PS ₅ Cl, Li ₆ PS ₅ Br, Li ₆ PS ₅ I, Li ₄ SnS ₄ , Li ₂ SnS ₃ , Li ₃ PS ₄ , Li ₇ P ₃ S ₁₁ , Li ₂ S·GeS ₂ , Li ₂ S·P ₂ S ₅ , Li ₂ S·P ₂ S ₅ ·LiI, Li ₂ S·As ₂ S ₅ ·SnS ₂ , Li ₇ P ₂ S ₈ I, Li ₄ PS ₄ I, Li ₇ P _2.9 S _10.85 Mo _0.01 , Li ₂ CuPS ₄ , (Li ₂ S) ₉ (P ₂ S ₅ ) ₃ (Ni ₃ S ₂ ), Li ₇ P _2.9 Mn _0.01 S _10.7 I _0.3 , Li _10.35 Sn _0.27 Si _1.08 P _1.65 S ₁₂ , Na ₃ PS ₄ , Na ₃ SbS ₄ , Na ₃ SnS ₄ , Na ₁₁ Sn ₂ PS ₁₂ , Na _3.75 Sn _0.75 Sb _0.25 S ₄ , Na _3.1 Sn _0.1 P _0.9 S ₄ , Na ₄ SiS ₄ , Na _2.375 PS _3.375 Cl _0.625 , Na ₃ P _0.62 As _0.38 S ₄ , Na ₃ PSe ₄ , Na ₁₀ GeS ₂ P ₁₂ , Na ₁₀ SnS ₂ P ₁₂ , Na ₁₀ SiS ₂ P ₁₂ , Na ₂ S, K ₂ S, Al ₂ S ₃ , ZnS, K ₃ PS ₄ .

According to the sulfur oxide solid electrolyte according to the first aspect of the present invention, the method comprises the following steps:

The sulfide solid electrolyte is put into a sealed container, and gaseous oxidant is introduced to obtain the sulfur oxide solid electrolyte;

Preferably, the flow rate of the gaseous oxidant is 10-100 cm ³ /min, preferably 20-50 cm ³ /min; and/or the oxidation reaction time is 10-100 min, preferably 20-60 min.

A second aspect of the present invention provides the preparation method of the sulfur oxide solid electrolyte described in the first aspect, the method comprising the following steps:

The sulfide solid electrolyte is put into a sealed container, and gaseous oxidant is introduced to obtain the sulfur oxide solid electrolyte;

Preferably, the flow rate of the gaseous oxidant is 10-100 cm ³ /min, preferably 20-50 cm ³ /min; and/or the oxidation reaction time is 10-100 min, preferably 20-60 min.

A third aspect of the present invention provides the preparation method of the sulfur oxide solid electrolyte described in the first aspect, the method comprising the following steps:

Putting the sulfide solid electrolyte into a sealed container, and using an inert gas as a carrier gas to introduce a liquid oxidant to obtain the sulfur oxide solid electrolyte;

Preferably, the inert gas is selected from one or more of the following: argon, nitrogen, hydrogen, helium; preferably argon;

More preferably, the flow rate of the gaseous oxidant is 10-100 cm ³ /min, preferably 20-50 cm ³ /min; and/or the oxidation reaction time is 10-100 min, preferably 20-60 min.

A fourth aspect of the present invention provides an all-solid-state battery, the all-solid-state battery comprising the sulfur oxide solid electrolyte as described in the first aspect.

A fifth aspect of the present invention provides the application of the sulfur oxide solid electrolyte described in the first aspect in preparing a chemical power source product; preferably, the chemical power source is an all-solid-state battery.

The sulfur oxide electrolyte has better air stability and chemical stability than existing sulfur oxide electrolytes.

The sulfur oxide solid electrolyte of the present invention effectively combines the advantages of high electrical conductivity, excellent mechanical properties and good air and chemical stability of the oxide solid electrolyte and avoids their disadvantages at the same time. The sulfur oxide solid electrolyte realizes the operation of the sulfide electrolyte in the battery dry room and assembles its all-solid-state battery, and the sulfur oxide solid electrolyte is prepared in situ and applied to the all-solid-state battery. The sulfur oxide solid electrolyte provided by the present invention is expected to be applied to the next-generation high specific energy battery, and is applied in practical life in preference to the sulfide solid electrolyte and the oxide solid electrolyte.

The sulfur oxide solid electrolyte system of the present invention can have, but is not limited to, the following beneficial effects:

The present invention provides a novel sulfur oxide solid electrolyte system. The sulfur oxide solid electrolyte effectively combines the advantages of high electrical conductivity, excellent mechanical properties, and good air and chemical stability of oxide solid electrolytes while avoiding their disadvantages. The sulfur oxide solid electrolyte can be prepared by oxidizing the existing sulfide electrolyte in dry air, so that the existing sulfide electrolyte can be operated in the battery drying room and its all-solid-state battery can be assembled, and the sulfur oxide solid electrolyte can be prepared and applied in situ. for all-solid-state batteries. The preparation method of the sulfur oxide solid electrolyte is simple and easy to operate, and is suitable for mass production. The sulfur oxide solid electrolyte improves the chemical stability of the existing sulfide electrolyte to air, to high-voltage oxide positive electrode materials and to negative electrode materials, and has smaller positive and negative electrode interface resistances. The sulfur oxide solid electrolyte provided by the present invention is expected to be applied to the next-generation high specific energy battery, and is applied in practical life in preference to the sulfide solid electrolyte and the oxide solid electrolyte.

Description of drawings

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein:

Figure 1 shows a preparation method for preparing a sulfur oxide solid electrolyte by directly oxidizing a sulfide solid electrolyte with an oxidant; wherein Figure 1(a) shows the preparation of a sulfur oxide solid electrolyte by directly oxidizing a sulfide solid electrolyte with an oxidizing gas; Figure 1 1(b) shows the preparation of sulfur oxide solid electrolyte by direct oxidation of sulfide solid electrolyte by oxidizing liquid; Fig. 1(c) shows the preparation and assembly of sulfur-containing solid electrolyte by direct oxidation of sulfide solid electrolyte by dry air in the cell drying room. All-solid-state batteries with oxide solid electrolytes.

Figure 2 shows three typical oxidation degrees and oxygen distributions of sulfur oxide solid electrolytes.

FIG. 3 shows a characteristic voltage curve of the sulfur oxide solid electrolyte contained in Example 1 in the first cycle.

FIG. 4 is a graph showing the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained in Example 2. FIG.

FIG. 5 is a graph showing the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained in Example 3. FIG.

FIG. 6 shows a characteristic voltage curve of the sulfur oxide solid electrolyte contained in Example 4 in the first cycle.

FIG. 7 shows the characteristic voltage curve of the sulfur oxide solid electrolyte contained in Example 5 in the first cycle.

FIG. 8 is a graph showing the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained in Example 6. FIG.

FIG. 9 is a graph showing the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained in Example 7. FIG.

FIG. 10 is a graph showing the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained in Comparative Example 1. FIG.

Detailed ways

The present invention is further described below through specific examples, but it should be understood that these examples are only used for more detailed and specific description, and should not be construed as being used to limit the present invention in any form.

This section provides a general description of the materials and test methods used in the tests of the present invention. While many of the materials and methods of operation used for the purposes of the present invention are known in the art, the present invention is described in as much detail as possible. It is clear to those skilled in the art that, in the context, if not specifically stated, the materials and methods of operation used in the present invention are well known in the art.

The reagents and instruments used in the following examples are as follows:

Reagents:

Lithium metal flakes, oxygen, ozone, sodium metal flakes, LiNi _0.8 Mn _0.1 Co _0.1 O ₂ , lithium indium alloy, silicon, nitric acid, sulfur, sulfur dioxide, sulfuric acid, NaCrO ₂ , TiS ₂ , LiNi _0.81 Co _0.15 Al _0.05 O ₂ from Sigma Corporation.

Sulfide solid electrolyte Li ₆ PS ₅ Cl, Li ₁₀ GeP ₂ S ₁₂ , Li _9.54 Si _1.74 P _1.44 S _11.7 Cl _0.3 , Li ₃ PS ₄ , Na _3.75 Sn _0.75 Sb _0.25 S ₄ , Na _2.375 PS _3.375 Cl _0.625 purchased from NEI Corporation.

instrument:

Chemical elemental analyzer, purchased from ThermoFisher Scientific model FlashSmart ElementalAnalyzer.

Focused Dual Beam Scanning Electron Microscope (FIB-SEM), purchased from ThermoFisher Scientific model Helios5 CX.

Example 1

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) The existing sulfide solid electrolyte adopts Li ₆ PS ₅ Cl, and the oxidant adopts oxygen.

(2) The specific preparation process of sulfur oxide solid electrolyte: put Li ₆ PS ₅ Cl into a sealed container (as shown in Figure 1a), then introduce high-purity oxygen, the air flow is controlled to be 50 cubic centimeters per minute, and the reaction time is 30 minute.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Li ₆ PS _4.5 O _0.5 Cl by chemical element analysis. The degree of oxidation and oxygen distribution of the sulfur oxide solid electrolyte were confirmed by focused double beam scanning electron microscope electron energy scattering spectroscopy (FIB-SEM-EDS). The sulfur oxide solid electrolyte has an ionic conductivity of 4×10 ^-3 S/cm and an electronic conductivity of 2×10 ^-10 S/cm.

(4) LiNi _0.8 Mn _0.1 Co _0.1 O ₂ was used as the positive electrode, Li ₆ PS _4.5 O _0.5 Cl was used as the electrolyte, and lithium indium alloy was used as the negative electrode, and an all-solid-state battery was assembled in a glove box.

(5) FIG. 3 is the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained therein. The hybrid battery has a reversible capacity of 150 mAh/g.

Example 2

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) The existing sulfide solid electrolyte adopts Li ₆ PS ₅ Cl, and the oxidant adopts dry air.

(2) The specific in-situ preparation process of sulfur oxide solid electrolyte and the assembly of all-solid-state batteries: Li ₆ PS ₅ Cl was pressed into electrolyte sheets in the battery drying room, and the positive electrode LiNi _0.8 Mn _0.1 Co _0.1 O ₂ and the negative electrode Li Indium were mixed with each other. The alloys are assembled into an all-solid-state battery. During the above operation, the sulfide solid electrolyte reacts with dry oxygen in the drying room to form a sulfur oxide solid electrolyte.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Li ₆ PS _4.75 O _0.25 Cl by chemical element analysis. It is confirmed by FIB-SEM-EDS that the oxidation degree and oxygen distribution of the sulfur oxide solid electrolyte are step oxidation and oxygen step distribution, wherein the content of oxygen on the surface of sulfur is about 3wt%, and the content gradually decreases to 0wt from the surface to the interior %. . The sulfur oxide solid electrolyte has an ionic conductivity of 8×10 ^-4 S/cm and an electronic conductivity of 3×10 ^-10 S/cm.

(4) FIG. 4 is the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained therein. The hybrid battery has a reversible capacity of 127 mAh/g.

Example 3

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) Li _9.54 Si _1.74 P _1.44 S _11.7 Cl _0.3 is used as the existing sulfide solid electrolyte, and ozone is used as the oxidant.

(2) The specific preparation process of sulfur oxide solid electrolyte: put Li _9.54 Si _1.74 P _1.44 S _11.7 Cl _0.3 into a sealed container (as shown in Figure 1a), then introduce high-purity ozone, and the air flow is controlled to be 30 cubic centimeters per minute, and the reaction The time is 60 minutes.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Li _9.54 Si _1.74 P _1.44 S ₁₀ O _1.7 Cl _0.3 by chemical element analysis. It was confirmed by FIB-SEM-EDS that the oxidation degree and oxygen distribution of the sulfur oxide solid electrolyte were surface oxidation and local distribution of oxygen on the surface, wherein the content of oxygen in the surface 50 of sulfur was about 6wt%, and the internal content was 0wt%. The sulfur oxide solid electrolyte has an ionic conductivity of 6×10 ^-4 S/cm and an electronic conductivity of 3×10 ^-9 S/cm.

(4) LiNi _0.81 Co _0.15 Al _0.05 O ₂ was used for the positive electrode, Li _9.54 Si _1.74 P _1.44 S ₁₀ O _1.7 Cl _0.3 for the electrolyte, and silicon for the negative electrode, and an all-solid-state battery was assembled in a battery drying room.

(5) FIG. 5 is the characteristic voltage curve of the first cycle of the sulfur oxide solid electrolyte contained. The hybrid battery has a reversible capacity of 126 mAh/g.

Example 4

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) The existing sulfide solid electrolyte adopts Li ₁₀ GeP ₂ S ₁₂ , and the oxidant adopts pure nitric acid.

(2) The specific preparation process of sulfur oxide solid electrolyte: put Li ₁₀ GeP ₂ S ₁₂ into a sealed container (as shown in Figure 1b), then use argon as a carrier gas to introduce nitric acid, and the gas flow is controlled to be 20 cubic centimeters per minute, and the reaction The time is 20 minutes.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Li ₁₀ GeP ₂ S ₁₀ O ₂ by chemical element analysis. It is confirmed by FIB-SEM-EDS that the oxidation degree and oxygen distribution of the sulfur oxide solid electrolyte are step oxidation and oxygen step distribution, wherein the content of oxygen on the surface of sulfur is about 10wt%, and the content gradually decreases to 0wt from the surface to the interior %. The sulfur oxide solid electrolyte has an ionic conductivity of 1×10 ^-3 S/cm and an electronic conductivity of 7×10 ^-10 S/cm.

(4) LiCoO ₂ is used for the positive electrode, Li ₁₀ GeP ₂ S ₁₀ O ₂ is used for the electrolyte, and graphite is used for the negative electrode, and an all-solid-state battery is assembled in a battery drying room.

(5) FIG. 6 is the characteristic voltage curve of the first cycle of the contained sulfur oxide solid electrolyte. The hybrid battery has a reversible capacity of 150 mAh/g.

Example 5

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) The existing sulfide solid electrolyte adopts Li ₃ PS ₄ , and the oxidant adopts dry air.

(2) Specific in-situ preparation process of sulfur oxide solid electrolyte and assembly of all-solid-state battery: Li ₃ PS ₄ was pressed into electrolyte sheets in the battery drying room, and the all-solid-state battery was assembled with positive element sulfur and negative metal lithium. During the above operation, the sulfide solid electrolyte reacts with dry oxygen in the drying room to form a sulfur oxide solid electrolyte.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Li ₃ PS _3.75 O _0.25 by chemical element analysis. It was confirmed by FIB-SEM-EDS that the oxidation degree and oxygen distribution of the sulfur oxide solid electrolyte were surface oxidation and local distribution of oxygen on the surface, wherein the content of oxygen in the surface 50 of sulfur was about 6.5wt%, and the internal content was 0wt% . . The sulfur oxide solid electrolyte has an ionic conductivity of 9×10 ^-4 S/cm and an electronic conductivity of 1×10 ^-9 S/cm.

(4) FIG. 7 is the characteristic voltage curve of the first cycle of the contained sulfur oxide solid electrolyte. The hybrid battery has a reversible capacity of 800 mAh/g.

Example 6

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) The existing sulfide solid electrolyte adopts Na _3.75 Sn _0.75 Sb _0.25 S ₄ , and the oxidant adopts sulfur dioxide.

(2) concrete sulfur oxide solid electrolyte preparation technology: put Na _3.75 Sn _0.75 Sb _0.25 S ₄ into a sealed container (as shown in Figure 1a), then feed high-purity sulfur dioxide, the air flow is controlled to be 20 cubic centimeters per minute, and the reaction time is 35 minutes.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Na _3.75 Sn _0.75 Sb _0.25 S _3.5 O _0.5 by chemical element analysis. It was confirmed by FIB-SEM-EDS that the oxidation degree and oxygen distribution of the sulfur oxide solid electrolyte were overall oxidation and oxygen distribution was uniform, and the oxygen content was 2.5 wt %. The sulfur oxide solid electrolyte has an ionic conductivity of 5×10 ^-3 S/cm and an electronic conductivity of 8×10 ^-10 S/cm.

(4) Using NaCrO ₂ as the positive electrode, Na _3.75 Sn _0.75 Sb _0.25 S _3.5 O _0.5 as the electrolyte, and metallic sodium as the negative electrode, an all-solid-state battery was assembled in a glove box.

(5) FIG. 8 is the characteristic voltage curve of the first cycle of the contained sulfur oxide solid electrolyte. The hybrid battery has a reversible capacity of 89 mAh/g.

Example 7

This example is used to illustrate the preparation and application of the novel sulfur oxide solid electrolyte of the present invention.

(1) The existing sulfide solid electrolyte adopts Na _2.375 PS _3.375 Cl _0.625 , and the oxidant adopts sulfuric acid.

(2) concrete sulfur oxide solid electrolyte preparation process: put Na _2.375 PS _3.375 Cl _0.625 into a sealed container (as shown in Figure 1b), then use argon as a carrier gas to feed sulfuric acid, and the air flow is controlled to be 25 cubic centimeters per minute, and the reaction The time is 25 minutes.

(3) The composition of the sulfur oxide solid electrolyte was confirmed to be Na _2.375 PS ₃ O _0.375 Cl _0.625 by chemical element analysis. It is confirmed by FIB-SEM-EDS that the oxidation degree and oxygen distribution of the sulfur oxide solid electrolyte are step oxidation and oxygen step distribution, wherein the content of oxygen on the surface of sulfur is about 5.5wt%, and the content gradually decreases from the surface to the interior to 0wt%. . The sulfur oxide solid electrolyte has an ionic conductivity of 4×10 ^-4 S/cm and an electronic conductivity of 2×10 ^-9 S/cm.

(4) TiS ₂ was used for the positive electrode, Na _2.375 PS ₃ O _0.375 Cl _0.625 for the electrolyte, and metal tin for the negative electrode, and an all-solid-state battery was assembled in a battery drying room.

(5) FIG. 9 is the characteristic voltage curve of the first cycle of the contained sulfur oxide solid electrolyte. The hybrid battery has a reversible capacity of 98 mAh/g.

Comparative Example 1

Other conditions are the same as in Example 1, except that the existing sulfide solid electrolyte Li ₆ PS ₅ Cl is used instead of the sulfur oxide solid electrolyte Li ₆ PS _4.5 O _0.5 Cl as the solid electrolyte of the all-solid-state battery. FIG. 10 is the characteristic voltage curve of the contained sulfur oxide solid electrolyte in the first week. The hybrid battery has a reversible capacity of 60 mAh/g.

Test Example 1

Compared with the existing sulfide solid electrolyte Li ₆ PS ₅ Cl, the Li ₆ PS _4.5 O _0.5 Cl prepared in Example 1 has better air stability and chemical stability. When Li ₆ PS ₅ Cl and Li ₆ PS _4.5 O _0.5 Cl were simultaneously exposed to air for half an hour, the ionic conductivity of Li ₆ PS ₅ Cl decreased from 2×10 ^-3 S/cm to 1×10 ^-4 S/cm cm; while the ionic conductivity of Li ₆ PS _4.5 O _0.5 Cl decreased from 4×10 ^-3 S/cm to 1×10 ^-3 S/cm. In addition, the all-solid-state battery in Example 1 using Li ₆ PS _4.5 O _0.5 Cl as the solid electrolyte has a higher reversible capacity than the all-solid-state battery in Comparative Example 1 using Li ₆ PS ₅ Cl as the solid electrolyte.

Although this invention has been described to a certain extent, it will be apparent that suitable changes in various conditions may be made without departing from the spirit and scope of the invention. It is to be understood that the invention is not limited to the embodiments described, but is to be included within the scope of the claims, which include equivalents for each of the elements described.

Claims (10)

1. A solid electrolyte of sulfur oxide, characterized in that it contains both sulfur and oxygen anions, and the general formula of the solid electrolyte of sulfur oxide is A_xM_yS_z-uO_u(ii) a Wherein:

a is a metal ion; preferably, a is selected from one or more of: lithium, sodium, potassium, magnesium, calcium, aluminum, zinc;

m is metal ion and/or non-metal ion; preferably, M is selected from one or more of: lithium, boron, carbon, nitrogen, fluorine, sodium, magnesium, aluminum, silicon, phosphorus, chlorine, potassium, calcium, scandium, titanium, vanadium, copper, zinc, gallium, germanium, zirconium, arsenic, selenium, bromine, strontium, yttrium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, cadmium, indium, tin, antimony, tellurium, iodine, tantalum, tungsten, lead, bismuth, lanthanum, cerium, samarium, europium;

s is sulfur and O is oxygen;

the value ranges of x, y, z and u are 0-20 respectively, and z is larger than u.

2. The sulfur oxide solid electrolyte according to claim 1, wherein the sulfur oxide solid electrolyte is obtained by directly oxidizing a sulfide solid electrolyte with an oxidizing agent;

preferably, the sulfide solid electrolyte has a general formula A_xM_yS_z。

3. The sulfur oxide solid electrolyte according to claim 2, wherein the oxidizing agent is an oxidizing gas or liquid;

preferably, the oxidant is selected from one or more of: oxygen, dry air, ozone, sulfur dioxide, sulfur trioxide, nitrogen dioxide, dinitrogen tetroxide, carbon monoxide, carbon dioxide, hydrogen peroxide, chloric acid, hypochlorous acid, nitric acid, sulfuric acid, sulfurous acid, bromic acid, hypobromous acid, iodic acid, hypoiodic acid and metaperiodic acid;

more preferably, the oxidizing agent is selected from oxygen, dry air, ozone, nitric acid, sulfur dioxide, and/or sulfuric acid.

4. The sulfur oxide solid electrolyte according to any one of claims 1 to 3, characterized in that the degree of oxidation of the sulfur oxide solid electrolyte is bulk oxidation, step oxidation or surface oxidation.

5. The sulfur oxide solid electrolyte according to any one of claims 1 to 4, wherein an ion conductance of the sulfur oxide solid electrolyte is more than 10^-7S/cm; and/or the electronic conductance of the sulfur oxide solid electrolyte is less than 10^-7S/cm。

6. The sulfur oxide solid electrolyte according to any one of claims 2 to 5, wherein the sulfide electrolyte is preferably selected from one or more of: li₁₀GeP₂S₁₂、Li₇GePS₈,Li_9.54Si_1.74P_1.44S_11.7Cl_0.3、Li₆PS₅Cl、Li₆PS₅Br、Li₆PS₅I、Li₄SnS₄、Li₂SnS₃、Li₃PS₄、Li₇P₃S₁₁、Li₂S·GeS₂、Li₂S·P₂S₅、Li₂S·P₂S₅·LiI、Li₂S·As₂S₅·SnS₂、Li₇P₂S₈I、Li₄PS₄I、Li₇P_2.9S_10.85Mo_0.01、Li₂CuPS₄、(Li₂S)₉(P₂S₅)₃(Ni₃S₂)、Li₇P_2.9Mn_0.01S_10.7I_0.3、Li_10.35Sn_0.27Si_1.08P_1.65S₁₂、Na₃PS₄、Na₃SbS₄、Na₃SnS₄、Na₁₁Sn₂PS₁₂、Na_3.75Sn_0.75Sb_0.25S₄、Na_3.1Sn_0.1P_0.9S₄、Na₄SiS₄、Na_2.375PS_3.375Cl_0.625、Na₃P_0.62As_0.38S₄、Na₃PSe₄、Na₁₀GeS₂P₁₂、Na₁₀SnS₂P₁₂、Na₁₀SiS₂P₁₂、Na₂S、K₂S、Al₂S₃、ZnS、K₃PS₄。

7. The method for producing the sulfur oxide solid electrolyte according to any one of claims 1 to 6, characterized by comprising the steps of:

putting the sulfide solid electrolyte into a sealed container, and introducing a gas oxidant to obtain the sulfur oxide solid electrolyte;

preferably, the flow velocity of the gas oxidant is 10-100 cm³A/min is preferably 20-50 cm³Min; and/or the oxidation reaction time is 10-100 min, preferably 20-60 min.

8. The method for producing the sulfur oxide solid electrolyte according to any one of claims 1 to 6, characterized by comprising the steps of:

putting the sulfide solid electrolyte into a sealed container, and introducing a liquid oxidant by taking inert gas as carrier gas to obtain the sulfur oxide solid electrolyte;

preferably, the inert gas is selected from one or more of: argon, nitrogen, hydrogen, helium; preferably argon;

more preferably, the flow velocity of the gas oxidant is 10-100 cm³A/min is preferably 20-50 cm³Min; and/or the oxidation reaction time is 10-100 min, preferably 20-60 min.

9. An all-solid battery characterized by comprising the sulfur oxide solid electrolyte according to any one of claims 1 to 6.

10. Use of the sulfur oxide solid electrolyte according to any one of claims 1 to 6 for producing a chemical power product; preferably, the chemical source of electrical energy is an all-solid-state battery.

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