Solid electrolyte, preparation method thereof and solid-state battery

Abstract

The invention belongs to the field of batteries, and particularly relates to a solid electrolyte, a preparation method thereof and a solid-state battery. The solid electrolyte comprises a core body and a protective layer coated on the surface of the core body, the core body comprises a sulfide electrolyte matrix, an amino compound, a transition metal oxide and a zeolite material; and the protective layer comprises a surface modifier. The HS inhibition efficiency of the sulfide solid electrolyte obtained by the technical scheme of the invention is remarkably improved, and the sulfide solid electrolyte has the advantages of high ionic conductivity maintenance, excellent battery performance and high process compatibility.

Description

Technical Field

[0001] This invention belongs to the field of batteries, specifically relating to a solid electrolyte, its preparation method, and a solid battery. Background Technology

[0002] Solid-state batteries, due to their high energy density and excellent safety, have become the core direction of next-generation energy storage technology. Sulfide-based solid electrolytes (such as Li6PS5Cl, Li3PS4, etc.) have ionic conductivity close to that of liquid electrolytes (10 Ω·cm at room temperature). -3 ~10 -2 Sulfide-based solid electrolytes (S / cm) are among the most promising solid-state electrolyte systems for industrialization. However, sulfide-based solid electrolytes face a key technological bottleneck: the amount of sulfur they contain... 2- PS4 3- Anions readily react with moisture (H2O) in the air (e.g., Li6PS5Cl + H2O → LiOH + H2S↑ + H3PO4) to generate toxic and corrosive H2S gas. This gas not only corrodes the battery casing and pollutes the production environment, but also reacts with cathode materials (such as NCM and LFP) to form insulating sulfides, leading to battery capacity decay and shortened lifespan, severely hindering the commercialization of sulfide solid-state batteries. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a solid electrolyte, its preparation method, and a solid battery.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A solid electrolyte includes a core and a protective layer covering the surface of the core; the core includes a sulfide electrolyte matrix, an amino compound, a transition metal oxide, and a zeolite material; the protective layer includes a surface modifier.

[0006] The amount of the amino compound added relative to the sulfide electrolyte matrix is ​​0.5-2%;

[0007] The amount of the transition metal oxide added relative to the sulfide electrolyte matrix is ​​0.3-1.5%;

[0008] The amount of the zeolite material added relative to the sulfide electrolyte matrix is ​​0.3-1.5%;

[0009] The amount of the surface modifier added relative to the core is 0.1-0.5%.

[0010] The sulfide electrolyte matrix is ​​at least one of Li6PS5Cl, Li6PS5Br, Li3PS4, Li4P2S7, and LLZO-LPS.

[0011] Preferably, the amino compound is at least one of triethanolamine, diethanolamine, ethylenediamine;

[0012] Preferably, the transition metal oxide is at least one of Fe2O3, CuO, ZnO;

[0013] Preferably, the zeolite material is 4A zeolite, 13X zeolite; preferably, the pore size of the zeolite material is 0.4-0.8 nm;

[0014] Preferably, the surface modifier is dodecyl mercaptan.

[0015] The ionic conductivity of the solid-state electrolyte is ≥0.90×10 -3 S / cm; the 24h H2S release amount is ≤0.09 ppm; the 30d H2S release amount is ≤0.28 ppm.

[0016] The application also includes a preparation method of the solid-state electrolyte, comprising the following steps: 1) first ball milling of the sulfide electrolyte matrix, the amino compound, and the transition metal oxide; 2) second ball milling after adding the zeolite material; 3) obtaining an intermediate product by heat treatment of the product of step 2); and 4) obtaining the solid-state electrolyte by modification of the intermediate product.

[0017] The sulfide electrolyte matrix and the transition metal oxide in step 1) are independently pretreated, and the pretreatment step is grinding the sulfide electrolyte matrix to a particle size of 15 μm under inert gas; and the transition metal oxide is refined to 50-100 nm by ball milling.

[0018] The specific step of step 1) is ball milling at a ball-to-material ratio of 10:1 and a rotation speed of 300-500 rpm, preferably 400 rpm, for 2-4 h, preferably 3 h, to obtain a uniformly dispersed mixed powder; and the step of step 2) is ball milling at a rotation speed of 100-400 rpm, preferably 300 rpm, for 1-2 h, preferably 1.5 h, to ensure uniform dispersion of the zeolite and no collapse of the microporous structure.

[0019] The specific step of step 3) is heat treatment at 75-120℃ for 1-5 h; preferably, heat treatment at 75-90℃ for 2.5 h, followed by heat treatment at 100-120℃ for 1.5 h.

[0020] The specific step of step 4) is dispersing the intermediate product in anhydrous ethanol and ultrasonic dispersion; adding a surface diluent and continuing to heat and stir to solidify to obtain the solid-state electrolyte; and the heating temperature is 50-70℃, preferably 60℃.

[0021] The application also comprises a solid-state battery, comprising a positive electrode, the solid-state electrolyte, and a negative electrode; preferably, the active material of the positive electrode is NCM811 or LFP; preferably, the active material of the negative electrode is metal Li or graphite.

[0022] Compared with the prior art, the application has the following beneficial effects:

[0023] The solid-state electrolyte of the application combines physical adsorption of zeolite, redox of transition metal oxide, and chemical fixation of amino compound, forming a three-level synergistic system of adsorption-oxidation-fixation; the zeolite first adsorbs H2O and generated H2S in the environment through micropores, reducing the direct reaction of the electrolyte with moisture; the transition metal oxide oxidizes S in H2S into stable S single element or sulfate through redox reaction (such as Fe2O3+3H2S→2FeS+S↓+3H2O, ZnO+H2S→ZnS↓+H2O); and the amino compound (such as triethanolamine) chemically fixes the residual H2S into non-volatile ammonium salt through acid-base neutralization reaction (-NH2+H2S→-NH3HS 2- ), completely blocking the release of H2S; + -

[0024] As a preferred embodiment, the amino compound, transition metal oxide, and sulfide electrolyte matrix are first ball milled to ensure uniform dispersion; then the zeolite is added for further ball milling; and finally, heat treatment is performed to promote the bonding (forming Li-O-C bond) of the interface between the amino compound and the sulfide electrolyte matrix, while avoiding the collapse of the microporous structure of the zeolite to ensure the adsorption performance.

[0025] The sulfide solid-state electrolyte obtained by the technical solution of the application has the following advantages: 1. H2S inhibition efficiency is significantly improved: under the environment of 85% RH and 25℃, the H2S release amount of the composite solid-state electrolyte is ≤0.09 ppm (determined by gas chromatography GB / T 14678-93), which is much lower than that of the electrolyte without adding protective material (H2S release amount ≥5 ppm), and the sulfur inhibition efficiency is more than 98%; and after 30 days of humidity exposure, the H2S release amount is still ≤0.28 ppm, and the long-term stability is better than that of the existing surface coating technology (the H2S release amount of the existing technology is ≥2 ppm after 30 days);

[0026] 2. High ion conductivity is maintained: the room temperature ion conductivity of the composite solid-state electrolyte is ≥0.9×10 -3 S / cm (tested by alternating current impedance method, frequency range 10 -1 ~ 10 6 Hz), which is higher than that of the unmodified sulfide electrolyte (1.2×10 -3 ​​The conductivity of the solid-state electrolyte is ≥0.9*10-3S / cm at-20℃, which solves the problem of conductivity reduction caused by the existing doping technology. -4 The conductivity of the solid-state electrolyte is ≥0.9*10-3S / cm at-20℃, which solves the problem of conductivity reduction caused by the existing doping technology.

[0027] 3. Excellent battery performance: The solid-state battery based on the composite electrolyte of the application (such as Li|solid-state electrolyte|NCM811) has a first discharge capacity ≥165mAh / g (LFP system) or ≥190mAh / g (NCM system) at 0.1C rate, and a capacity retention rate ≥92% after 100 cycles, which is much higher than that of a single doping system (≤80%);

[0028] 4. Strong process compatibility: The preparation process does not require special equipment (conventional ball milling and heat treatment equipment), and can be directly adapted to the existing roll-to-roll and dry forming process of solid-state batteries, with low production cost (more than 30% reduction compared with surface coating technology) and easy industrialization. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a schematic diagram of the H2S synergistic inhibition mechanism of the sulfide solid-state electrolyte of the application;

[0030] Figure 2 is a comparison scatter plot of the H2S release amount of different solid-state electrolytes of the application.

[0031] Figure 3 is the ion conductivity temperature curve of Example 1 and Comparative Example 6 of the application. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the technical solutions of the application, the application will be further described in detail below with reference to the drawings and the best mode.

[0033] Example 1: Preparation method of solid-state electrolyte, main raw materials based on Li6PS5Cl (purity 99.9%, particle size 1-3μm), triethanolamine, Fe2O3 (particle size 50-80nm, purity 99.5%), 4A zeolite (pore size 0.4nm, specific surface area ≥700m 2 / g), UDSH (dodecyl mercaptan)

[0034] Pretreatment: Li6PS5Cl was ground in an Ar glove box for 30min and passed through a 200-mesh sieve; Fe2O3 was ball milled for 2h using a planetary ball mill (rotation speed 500rpm) to refine it to 50-80nm;

[0035] comprising the following steps: 1) first step ball milling: take 100 g Li6PS5Cl, 1.5 g triethanolamine, 1 g Fe2O3 into a maroon ball milling tank (ball to material ratio 10:1), rotate at 400 rpm for 3 h, to obtain mixed powder A;

[0036] 2) second step ball milling: add 1 g 4A zeolite to the mixed powder A, rotate at 300 rpm for 1.5 h, to obtain mixed powder B;

[0037] 3) heat treatment: transfer the mixed powder B to a quartz boat, and keep at 80℃ for 2 h and at 110℃ for 1 h under Ar atmosphere, and naturally cool to room temperature, to obtain C.

[0038] 4) surface modification: disperse the intermediate product powder in anhydrous ethanol, and ultrasonic for 10 min (300 W) at a concentration of 0.1 g / mL; add 0.05 g / mL UDSH / ethanol solution (volume ratio 10:1), and stir at 60℃ for 2 h; after centrifugation, vacuum dry at 80℃ for 4 h, to obtain Sample-1;

[0039] Performance test: H2S release amount: place Sample-1 in a constant temperature and humidity box at 85% RH and 25℃, and after 24 h, detect the H2S concentration by gas chromatography (Agilent 7890A), and the result is 0.08 ppm; after 30 days, the H2S concentration is 0.25 ppm;

[0040] Ionic conductivity: test by alternating current impedance method (Solartron 1260), and the conductivity is 1.1×10-3 S / cm at room temperature (25℃) and 1.2×10 -4 S / cm at-20℃;

[0041] Battery performance: assemble Li|Sample-1|NCM811 battery (positive electrode sheet: NCM811 / Super P / PVDF=8:1:1, negative electrode: metal Li foil), and the first discharge capacity is 192 mAh / g at 0.1C rate, and the capacity retention rate is 93.5% after 100 cycles,

[0042] Other examples and comparative examples have the same test method as this example.

[0043] Example 2: preparation method of solid-state electrolyte, main raw materials based on Li3PS4 (prepared by solid phase reaction of Li2S and P2S5 at 400℃, particle size 2-5 μm), diethanolamine, CuO (particle size 30-50 nm), 13X zeolite (pore size 0.8 nm, specific surface area ≥800 m 2 / g), UDSH (dodecyl mercaptan);

[0044] Pre-treatment: Li3PS4 was ground to 25 pm in size; CuO was ball-milled to 30-50 nm;

[0045] The method comprises the following steps: 1) first step ball-milling: 100 g of Li3PS4, 1 g of diethanolamine, and 0.8 g of CuO are taken, and ball-milling is performed at a rotating speed of 350 rpm for 3.5 h to obtain mixed powder A;

[0046] 2) second step ball-milling: 0.8 g of 13X zeolite is added, and ball-milling is performed at a rotating speed of 280 rpm for 2 h to obtain mixed powder B;

[0047] 3) heat treatment: heat treatment is performed at 75 °C for 2.5 h and then at 105 °C for 1.5 h under an Ar atmosphere to obtain intermediate powder C.

[0048] 4) surface modification: the intermediate product powder is dispersed in anhydrous ethanol, and ultrasonic treatment is performed for 10 min (300 W) at a concentration of 0.1 g / mL; 0.05 g / mL of UDSH / ethanol solution (volume ratio of 10:1) is added, and stirring is performed at 60 °C for 2.5 h; after centrifugation, vacuum drying is performed at 80 °C for 4 h to obtain Sample-2.

[0049] Example 3: a preparation method of a solid-state electrolyte, and main raw materials are based on Li6PS5Cl (purity of 99.9%, particle size of 1-3 pm) and ZnO (particle size of 60-100 nm, purity of 99.9%), triethanolamine, ZnO (particle size of 60-100 nm), 4A zeolite (pore size of 0.4 nm, specific surface area of ≥700 m 2 / g) UDSH (dodecyl mercaptan)

[0050] Pre-treatment: Li6PS5Cl is ground in an Ar glove box for 30 min and passed through a 200-mesh sieve; ZnO nanopowder is directly used without additional treatment.

[0051] The method comprises the following steps: 1) first step ball-milling: 100 g of Li6PS5Cl, 1.2 g of triethanolamine, and 1.2 g of ZnO are taken and added into a maroon ball mill tank (ball-to-powder ratio of 10:1), and ball-milling is performed at a rotating speed of 400 rpm for 3 h to obtain mixed powder A.

[0052] 2) second step ball-milling: 1.0 g of 4A zeolite is added to the mixed powder A, and ball-milling is performed at a rotating speed of 300 rpm for 1.5 h to obtain mixed powder B.

[0053] 3) heat treatment: the mixed powder B is transferred into a quartz boat, and heat treatment is performed at 80 °C for 2 h and then at 110 °C for 1 h under an Ar atmosphere, and natural cooling is performed to room temperature to obtain intermediate product powder C.

[0054] 4) Surface modification: The intermediate product, powder C, was dispersed in anhydrous ethanol (concentration 0.1 g / mL) and ultrasonically treated for 10 min (300 W). Then, 0.05 g / mL of UDSH / ethanol solution (volume ratio 10:1) was added, and the reaction was stirred at 60 °C for 2.5 h (to ensure that the -SH groups of UDSH were combined with the Zn 2+ After the reaction was completed, centrifugal separation was performed, and the solid product was vacuum dried at 80 °C for 4 h to obtain the final product, which was denoted as Sample-3.

[0055] Comparative Example 1: The difference from Example 1 is only that the single zeolite-doped Li6PS5Cl electrolyte does not contain an amino compound, a transition metal oxide, and a surface modifier, and only 2.5 g of 4A zeolite is added to 100 g of Li6PS5Cl, followed by ball milling for 3 h and heat treatment (110 °C, 2 h) to obtain Sample-C1.

[0056] Comparative Example 2: The difference from Example 1 is only that the single amino compound-doped Li6PS5Cl electrolyte does not contain a zeolite material, a transition metal oxide, and a surface modifier, and includes the following steps: 1) ball milling: 100 g of Li6PS5Cl and 2.5 g of triethanolamine are added to a agate ball mill jar (ball-to-material ratio 10:1), and ball milling is performed at a rotation speed of 400 rpm for 3 hours to uniformly coat the triethanolamine on the surface of the electrolyte particles; 2) heat treatment: the mixed powder after ball milling is heat treated at 110 °C for 2 hours under an Ar atmosphere to promote the partial bonding of the triethanolamine to the surface of the electrolyte and remove a small amount of volatile components, and the sample obtained after cooling is denoted as Sample-C2.

[0057] The performance test results are shown in Table 1. The test results of Comparative Example 2 show that a single amino compound can fix a part of H2S through chemical action, but lacks the cooperation of the front-end physical adsorption (zeolite) and oxidation conversion (Fe2O3) mechanisms, cannot effectively block the invasion of moisture and timely treat a large amount of generated H2S, and thus has limited inhibition efficiency and poor long-term stability (the amine substance may be consumed or fail). The ionic conductivity is 0.7 x 10 -3 S / cm, which is significantly lower than that of Example 1 of the present application (~1.1 x 10 -3 S / cm), because the excess organic amine molecules (2.5 wt%) can partially cover the lithium ion transmission channels, increasing the interface impedance. The capacity retention rate of the battery is only 78.5% after 100 cycles at a rate of 0.1C. This is due to two reasons: one is that the residual H2S gas corrodes the positive electrode interface; and the other is that the low ionic conductivity leads to increased battery polarization, accelerating capacity decay.

[0058] Comparative Example 3, the only difference from Example 1 is that the single sodium peroxycarbonate-doped Li6PS5Cl electrolyte was prepared by the following steps: 100 g of Li6PS5Cl and 2.5 g of sodium peroxycarbonate were directly added into a maroon ball mill tank (ball-to-powder ratio of 10:1), and ball-milled at a rotation speed of 400 rpm for 3 h to ensure uniform mixing. The mixed powder after ball-milling was heat-treated at 110 °C for 2 h under an Ar atmosphere, and the sample obtained after cooling was recorded as Sample-C3.

[0059] Comparative Example 4, the only difference from Example 1 is that the zeolite material was not contained in step 1); but the relevant steps of containing an amino compound, a transition metal oxide, and a surface modifier, specifically including: 1) first step ball-milling: Li6PS5Cl, triethanolamine, and Fe2O3 were ball-milled according to the same parameters as in Example 1 for 3 h to obtain a mixed powder. 2) heat treatment: the powder after the first step ball-milling was heat-treated according to the same parameters as in Example 1 (80 °C / 2 h + 110 °C / 1 h) to obtain an intermediate powder. Surface modification: the intermediate powder was modified with UDSH according to the same process as in Example 1 (reaction at 60 °C for 2 h), and finally the sample was obtained and recorded as Sample-C4.

[0060] The performance test results are shown in Table 1, which show that the lack of zeolite for initial adsorption of H2O and H2S, more moisture directly reacts with the electrolyte, and the generated H2S cannot be effectively enriched and subsequently converted, resulting in a decrease in inhibition efficiency and poor long-term stability. Ionic conductivity (25 °C): 1.0 x 10 -3 S / cm (close to the example, proving that the lack of zeolite has little effect on ionic conductivity). The capacity retention rate after 100 cycles of the battery was 85.2%. Since the H2S inhibition is not complete, there are still side reactions at the positive electrode interface, so the capacity retention rate is lower than that of the present application.

[0061] Comparative Example 5, the only difference from Example 1 is that no amino compound is included in Step 1); but the relevant steps of including zeolite material, transition metal oxide, and surface modifier, specifically including: 1) first step ball milling: Li6PS5Cl and Fe2O3 are ball milled for 3 h according to the parameters of Example 1. 2) second step ball milling: zeolite is added to the above-mentioned powder, and ball milling is carried out for 1.5 h according to the parameters of Example 1 to obtain a mixed powder B. 3) heat treatment: the mixed powder B is heat treated according to the parameters of Example 1. Due to the absence of an amino compound, this step only serves to dry and stabilize the structure. 4) surface modification: the same process as Example 1 is used to obtain a sample, which is denoted as Sample-C5. The performance test is shown in Table 1, which shows that the first two lines of defense (zeolite adsorption, Fe2O3 oxidation) can play a certain role, but due to the lack of the last chemical fixation step, the residual H2S cannot be completely removed, resulting in a gradual increase in H2S release after long-term storage, and poor stability. The capacity retention rate is 82.8% after 100 cycles of battery cycling. The un-fixed trace amount of H2S continuously corrodes the positive electrode interface, resulting in a lower capacity retention rate than the complete system of the present application.

[0062] Comparative Example 6, the only difference from Example 1 is that the Li6PS5Cl is not modified, and the pretreatment: 100 g of Li6PS5Cl is ground in an Ar glove box (water and oxygen content ≤0.1 ppm) for 30 min, sieved through a 200 mesh sieve to remove particle agglomerates, and ensure that the particle size is consistent with the pretreated electrolyte matrix in Example 1; drying treatment: the ground Li6PS5Cl powder is transferred to a quartz boat and heated at 80°C for 2 h and then at 110°C for 1 h under Ar atmosphere (the heat treatment temperature and time are completely consistent with those of Example 1), which is only used to remove the trace amount of water adsorbed on the surface of the powder to avoid water interference with the H2S release test; product collection: after natural cooling to room temperature, unmodified Li6PS5Cl is obtained, denoted as Sample-C6. The performance test is shown in Table 1, which shows that the unmodified Li6PS5Cl, due to the lack of a "zeolite physical adsorption-transition metal oxide oxidation-amino compound chemical fixation" synergistic sulfur inhibition system, contains S 2- , PS4 3- anions are easily continuously reacted with moisture in the air to generate H2S, and there is no mechanism to adsorb, convert or fix H2S, resulting in a much higher H2S release than the modified system, and continuously increasing with the extension of storage time, and poor long-term humidity stability. Ionic conductivity (25°C): 1.2 x 10 -3 S / cm. Slightly higher than the composite electrolyte of the present application (e.g. 1.1 x 10 -3S / cm), but the advantage is derived from the additive covering the lithium ion transmission channel, not the better conduction performance of the material itself, and the advantage will be quickly lost due to the interface side reaction caused by H2S in subsequent battery cycles. The first discharge capacity of the battery at 0.1C rate is 188 mAh / g, and the capacity retention rate after 100 cycles is 68.5%. The slightly lower first discharge capacity is due to the reaction of H2S with the surface of NCM811 positive electrode to generate insulating sulfides such as NiS and CoS, which increases the initial interface impedance; the significant cycle capacity decay is due to the continuous generation of H2S accelerating the dissolution of transition metal ions in the positive electrode and destroying the positive electrode crystal structure, which is far lower than the battery performance of the composite electrolyte system of the present application (such as the capacity retention rate of 93.5% after 100 cycles in Example 1).

[0063] Table 1

[0064]

[0065] It can be seen from Table 1 and Figures 2-3 It can be seen from Table 1 and Figure 1 is a schematic diagram of the H2S synergistic inhibition mechanism of the sulfide solid electrolyte of the present application; Figure 2 is a comparison scatter plot of the H2S release amount of different solid electrolytes of the present application; Figure 3 is the ion conductivity temperature curve of Example 1 and Comparative Example 6 of the present application). The present application has universality and superiority: the performance of Examples 1, 2 and 3 (using Fe2O3, CuO and ZnO respectively) is overall and significantly better than all the comparative examples. This shows that the core idea of "multi-component synergy" of the present application has universality for different active components (transition metal oxides), and is not a chance effect of individual materials. Among them, the ZnO system (Example 3) shows the most excellent comprehensive performance.

[0066] 2. There are fundamental defects in a single mechanism: Comparative Examples 1 and 2 prove that any single mechanism (only physical adsorption or only chemical fixation) has an insurmountable shortcoming, and cannot simultaneously achieve efficient sulfur inhibition, high ion conductivity and long-term stability.

[0067] 3. The "synergistic mechanism" is an organic whole: Comparative Examples 4 and 5, like "disassembling blocks", verify that the physical adsorption layer and the chemical fixation layer in the three-level synergistic system of "adsorption-oxidation-fixation" of the present application are indispensable functional units. The long-term stability will decrease significantly if any layer is missing, proving that the system is an organic whole with complementary functions and synergistic effects.

[0068] 4. Solving the core contradiction in the industry: Comparative Example 3 proves that even if there is a certain sulfur inhibition effect, but at the expense of serious sacrifice of core performance (ion conductivity), the scheme is not desirable. All examples of the present application successfully maintain the ion conductivity at a high level comparable to the base electrolyte (≥0.9×10-3 S / cm), perfectly solve the traditional contradiction that it is difficult to consider both "sulfur inhibition" and "conductivity".

[0069] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A solid state electrolyte, characterized by, The core comprises a sulfide electrolyte matrix, an amino compound, a transition metal oxide, and a zeolite material; the protective layer comprises a surface modifier.

2. The method of producing a solid-state electrolyte according to claim 1, characterized by, The addition amount of the amino compound relative to the sulfide electrolyte matrix is 0.5-2%; preferably 1-1.5%; The addition amount of the transition metal oxide relative to the sulfide electrolyte matrix is 0.3-1.5%; preferably 0.8-1.2%; The addition amount of the zeolite material relative to the sulfide electrolyte matrix is 0.3-1.5%, preferably 0.8-1%; The addition amount of the surface modifier relative to the core is 0.1-0.5%, preferably 0.5%.

3. The method of producing a solid-state electrolyte according to claim 1, characterized by, The sulfide electrolyte matrix is at least one of Li6PS5Cl, Li6PS5Br, Li3PS4, Li4P2S7, and LLZO-LPS; Preferably, the amino compound is at least one of triethanolamine, diethanolamine, and ethylenediamine; Preferably, the zeolite material is 4A zeolite or 13X zeolite; preferably, the pore size of the zeolite material is 0.4-0.8 nm; Preferably, the transition metal oxide is at least one of Fe2O3, CuO, and ZnO; Preferably, the surface modifier is dodecyl mercaptan.

4. The solid-state electrolyte of claim 1, wherein, The solid-state electrolyte has an ionic conductivity of ≥ 0.90 x 10 -3 S / cm; a 24h H2S release of ≤ 0.09 ppm; and a 30d H2S release of ≤ 0.28 ppm.

5. A method of producing the solid-state electrolyte according to any one of claims 1 to 4, characterized by, The method comprises the following steps: 1) first ball milling of the sulfide electrolyte matrix, the amino compound, and the transition metal oxide; 2) second ball milling after adding the zeolite material; 3) heat treatment of the product of step 2) to obtain an intermediate product; and 4) modification of the intermediate product to obtain a solid-state electrolyte.

6. The preparation method according to claim 5, characterized in that, In step 1), the sulfide electrolyte matrix and the transition metal oxide are independently pretreated, and the pretreatment steps are as follows: the sulfide electrolyte matrix is ground to a particle size of 15 μm under inert gas; and the transition metal oxide is refined to a particle size of 50-100 nm by ball milling.

7. The preparation method according to claim 5, characterized in that, In step 1), the specific steps are as follows: ball milling is performed at a ball-to-material ratio of 10:1 and a rotation speed of 300-500 rpm, preferably 400 rpm, for 2-4 h, preferably 3 h, to obtain a uniformly dispersed mixed powder; and in step 2), the specific steps are as follows: ball milling is performed at a rotation speed of 100-400 rpm, preferably 300 rpm, for 1-2 h, preferably 1.5 h, to ensure uniform dispersion of the zeolite and prevent collapse of the microporous structure.

8. The preparation method according to claim 5, characterized in that, In step 3), the specific steps are as follows: heat treatment is performed at 75-120 ℃ for 1-5 h; preferably, heat treatment is performed at 75-90 ℃ for 2.5 h, followed by heat treatment at 100-120 ℃ for 1.5 h.

9. The preparation method according to claim 5, characterized in that, In step 4), the specific steps are as follows: the intermediate product is dispersed in anhydrous ethanol and ultrasonically dispersed; a surface diluent is added, and heating and stirring are continued to obtain a solid-state electrolyte; and the heating temperature is 50-70 ℃, preferably 60 ℃.

10. A solid state battery, characterized by The battery comprises a positive electrode, a solid-state electrolyte according to any one of claims 1-4, and a negative electrode; preferably, the active material of the positive electrode is NCM811 or LFP; and preferably, the active material of the negative electrode is metallic Li or graphite.

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