40 results about "Lithium iodide" patented technology

The application provides a preparation method of anhydrous lithium iodide, and belongs to the field of new energy solid-state batteries. The method comprises the following steps in sequence: mixing a lithium source and an iodine source, obtaining a mixed solution after reaction, removing impurities by filtration to obtain a filtrate; the filtrate is subjected to frozen impurity separation, and after filtration, the liquid is a frozen clear solution, and the solid is a sodium salt or a potassium salt; the frozen clear solution is heated and evaporated to concentrate, when the solid content is 50%-70%, heating is stopped, lithium iodide concentrated slurry is obtained, the lithium iodide concentrated slurry is cooled to room temperature under stirring to obtain lithium iodide one-evaporation crystal slurry, after centrifugation, one-evaporation wet product and primary mother liquor are obtained; the one-evaporation wet product is dissolved in water and filtered, and then the heating and evaporation concentration process of step c is repeated to obtain two-evaporation wet product and secondary mother liquor; the two-evaporation wet product is heated and self-dissolved, and after spray drying, anhydrous lithium iodide is obtained. The anhydrous lithium iodide prepared by the method has a purity greater than or equal to 99.9%, and can be applied to the field of solid-state batteries.

This invention relates to a method for iodine-induced lithium intercalation and exfoliation of two-dimensional materials, comprising the following steps: uniformly mixing a target bulk layered material with an inorganic salt to obtain mixture A; the inorganic salt contains lithium iodide; heating mixture A to 280–400°C under a vacuum environment or protective atmosphere, while simultaneously applying ultraviolet light irradiation, and obtaining mixture B through solid-state lithiation treatment; dispersing mixture B in deionized water, and obtaining the two-dimensional material through hydrolysis exfoliation, separation, washing, and drying. This invention uses an inorganic salt containing lithium iodide as the intercalation medium, and through the synergistic excitation of a light field and a thermal field, induces the oxidative decomposition of halide ions and the release of electrons, driving alkali metal ions to intercalate into the interlayer gaps of the bulk layered material to achieve in-situ solid-state intercalation. Then, through hydrolysis exfoliation, an ultrathin two-dimensional material with a large lateral dimension is obtained. The process is safe, has high intercalation efficiency, and good versatility.

The application discloses a method for preparing a disulfide at low temperature, which comprises the following steps: coupling reaction of m-dihalobenzene and a mercapto compound in the presence of sodium hydride and lithium iodide to prepare the disulfide. At present, the existing methods for synthesizing a disulfide have some problems to a greater or lesser extent. Either noble metal catalysis is needed, the cost is high, and there is a risk of heavy metal residue in the product; or the reaction operation is complex and complicated, and the reaction condition is harsh. The application develops a new method, which can start from cheap and readily available raw materials, use cheap initiators, and simply and effectively synthesize a disulfide under mild reaction conditions, so as to meet the needs of research and development and actual production.

The preparation method comprises the following steps: mixing a lithium source material, water, a first solvent and quaternary amine alkali, reacting the quaternary amine alkali with carbon dioxide in a reaction atmosphere containing carbon dioxide to generate HCO3 <->, reacting the HCO3 <-> with lithium ions in the lithium source material to generate lithium bicarbonate, and collecting a water phase after the reaction; decomposing lithium bicarbonate in the water phase to generate lithium carbonate, collecting a solid phase, and decomposing lithium carbonate in the solid phase to generate lithium oxide to obtain an intermediate; dissolving quaternary ammonium iodide in a second solvent, adding the intermediate, converting the lithium oxide into lithium hydroxide, carrying out ion exchange on the lithium hydroxide and the quaternary ammonium iodide to generate lithium iodide, and collecting a liquid phase; and collecting the lithium iodide in the liquid phase. According to the present invention, based on the characteristics of the specific quaternary ammonium base and the quaternary ammonium iodide salt, the Li in the lithium source material is selectively reinforced, carbonized and leached, the anion impurities in the lithium source material are removed, the anion exchange in the organic phase is achieved, and the high-purity anhydrous lithium iodide is prepared.

A fiber-reinforced lithium borohydride-based all-solid-state electrolyte for suppressing dendrite formation, its preparation method, and its application are disclosed. The method employs a reverse micelle precipitation method to prepare a precursor solution by dissolving lithium borohydride and lithium iodide in an ether solvent solution. Aluminum oxalate and vapor-grown carbon fibers are then added, followed by dropwise addition to an isopentane solution containing a surfactant. After reverse micelles form, the solution is allowed to settle and react completely, and the solvent is thoroughly removed. The product from the settled reaction is dried and then subjected to partial hydrogen release treatment. The partially hydrogen-released product is dispersed in a benzene solution containing polymethyl methacrylate, freeze-dried, and then melt-reacted in situ in a universal mold. This process is simple and highly controllable, significantly improving the mechanical stability and dendrite resistance of the lithium borohydride-based all-solid-state electrolyte, and enabling long lifespan of all-solid-state lithium batteries under fast-charging conditions, thus facilitating commercial applications.

The invention discloses a method for recovering elemental iodine, which comprises the following steps of: performing adsorption-elution treatment on waste gas or waste oil generated in the preparation process of anhydrous lithium iodide, and recovering the elemental iodine from eluent. According to the method, the iodine simple substance escaped by evaporation in the preparation process of lithium iodide trihydrate and the iodine simple substance dissolved in the vacuum pump oil after the lithium iodide trihydrate is subjected to gradient vacuum drying can be efficiently recovered, so that the defects of serious volatilization loss, serious pollution and high occupational risk of the iodine simple substance in the existing preparation process of anhydrous lithium iodide are overcome; the efficient recovery of iodine resources is realized, the production cost is reduced, and meanwhile, the pollution to the environment and the harm to people are reduced.

The present application belongs to the technical field of lithium-sulfur full solid electrolyte, and discloses a preparation method of a PEO-based solid-state lithium-sulfur battery without a negative electrode. Lithium iodide is in-situ coated on LLZTO, and the same is dissolved with Li2S6 and PEO in anhydrous acetonitrile to form a solid-state electrolyte; a sulfur positive electrode sheet is obtained by mixing carboxymethyl cellulose lithium / styrene-butadiene rubber adhesive with sulfur and ketchen black molten sulfur. The electrolyte and the positive electrode sheet prepared above can be assembled into a full solid-state lithium-sulfur battery without a negative electrode, thereby improving safety, reducing cost, increasing the energy density of the battery, inhibiting the dissolution of long-chain lithium polysulfide in the PEO-based full solid-state lithium-sulfur battery, increasing the utilization rate of active substances in the battery, improving the cycle life and stability of the battery, and realizing high sulfur loading of the PEO-based full solid-state lithium-sulfur battery.

The application discloses a modified bismuth oxyiodide-based composite solid-state polymer electrolyte and a lithium battery construction method thereof, and the method comprises the following steps: preparing a metal bismuth oxyiodide compound or a bismuth oxyiodide compound with defects, and preparing the bismuth oxyiodide-based composite solid-state polymer electrolyte by taking the compound as a filler. The electrolyte has the characteristics of high ionic conductivity and high mechanical strength, the bismuth oxyiodide can react in situ with a lithium negative electrode to form an SEI with lithium iodide, and the growth of dendrites is inhibited; through modification of the bismuth oxyiodide, the interface contact between a polymer and inorganic fillers can be improved, and the ionic conductivity of the composite electrolyte is improved. The composite electrolyte can match a lithium iron phosphate, NCM811 and sulfur positive electrode, and a high-conductivity and high-stability solid-state battery is realized.

The present application relates to a modified solid-state electrolyte material, a preparation method thereof and a full solid-state lithium ion battery, and belongs to the technical field of full solid-state lithium ion batteries.The modified solid-state electrolyte material comprises solid-state electrolyte particles and a lithium iodide and ethyllithium complex coating layer coated on the surface of the solid-state electrolyte particles.The preparation method comprises coating LiI on the surface of the solid-state electrolyte particles to obtain LiI-coated solid-state electrolyte particles;mixing the LiI-coated solid-state electrolyte particles with C2H5Li, and then complexing by heating to form a lithium iodide and ethyllithium complex coating layer on the surface of the solid-state electrolyte particles, thereby obtaining the modified solid-state electrolyte material.The modified solid-state electrolyte material can significantly improve the compatibility of the solid-state electrolyte and the pole piece, and has low cost.

The present invention relates to a method for producing a lithium halide compound, capable of industrially advantageously producing a lithium halide compound having a low water content, particularly lithium bromide and lithium iodide, at a high reaction efficiency without accompanying a step of directly removing water, and the method including mixing lithium sulfide, a halogen molecule of at least one of bromine and iodine, and a first solvent; and removing the first solvent, wherein the first solvent is a solvent that dissolves a lithium halide containing the same halogen element as the halogen molecule.

The invention discloses a pyrite-based composite positive electrode material, a preparation method thereof and an application of the pyrite-based composite positive electrode material in an all-solid-state battery, the preparation method of the pyrite-based composite positive electrode material comprises the following steps: (1) carrying out oscillation ball milling treatment on pyrite square crystals to obtain iron sulfide fine powder; (2) mixing lithium sulfide and lithium iodide, and then carrying out high-energy ball milling treatment to obtain a lithium-iodine-sulfur amorphous mixture; and (3) mixing the iron sulfide fine powder and the lithium-iodine-sulfur amorphous mixture, and then carrying out high-energy ball milling treatment to obtain the pyrite-based composite positive electrode material. The pyrite-based composite positive electrode material is combined with a solid electrolyte membrane and a lithium-indium negative electrode, so that a high-capacity and low-attenuation pyrite composite positive electrode sulfide all-solid-state battery can be prepared, and high specific capacity and long circulation performance are shown.

The application relates to a self-bleaching electrochromic device based on titanium dioxide and lithium iodide, and belongs to the technical field of electrochromic devices. The application discloses a self-bleaching electrochromic device based on titanium dioxide and lithium iodide, which comprises a non-polar self-bleaching electrochromic device or a polar self-bleaching electrochromic device. The application has the following advantages: (1) the cycle life of the electrochromic device is improved, and the color change contrast of the electrode in the 300nm-800nm visible light band is less than 5% after at least 4000 coloring-bleaching on-off cycle operations; (2) the electrode is self-bleached, that is, the electrode can be completely restored to the state before color change within 60s under the condition of no additional voltage; and (3) the device is non-polar, that is, both electrodes can be used as cathodes or anodes, and can normally work under the condition of an additional positive or negative voltage, and the same color change performance index is achieved.

This invention belongs to the technical field of comprehensive recycling of waste lithium-ion power batteries, specifically relating to a method for recovering battery-grade lithium carbonate from the cathode material of waste lithium iron phosphate batteries. In the recycling process of this invention, lithium iodide is added as a precipitant for impurity metal ions. This not only utilizes the extremely low solubility of Cu, Al, and Mg iodides in anhydrous ethanol, while LiI is highly soluble in ethanol, but also ensures complete precipitation of impurity ions such as Cu, Al, and Mg in the lithium-rich solution, thus achieving impurity removal. Furthermore, in the subsequent lithium precipitation process to prepare lithium carbonate, the added lithium iodide can be converted into lithium carbonate, realizing the secondary utilization of the input material. That is, lithium iodide is used as both an impurity precipitant and a raw material, saving costs and generating revenue.

The invention discloses low-water-content anhydrous lithium iodide as well as a preparation method and application thereof, and relates to the technical field of lithium iodide production. The ceramic grinding balls are added into the lithium iodide trihydrate concentrated solution for vacuum heating and drying, so that autolysis of lithium iodide in the drying process can be effectively avoided, water in the lithium iodide trihydrate concentrated solution can be removed in a targeted manner, and meanwhile, due to the fact that the ceramic grinding balls are added for vacuum heating and drying, the drying efficiency of the lithium iodide trihydrate concentrated solution is improved. After drying is finished, ball milling can be directly carried out, operation steps are saved, and after ball milling is finished, open drying is carried out, so that moisture generated in the transferring process of the anhydrous lithium iodide coarse material can be quickly, simply and conveniently removed. The preparation method can obtain the anhydrous lithium iodide with low water content, has the advantages of simple operation, mild reaction conditions and low operation cost, and is beneficial to large-scale production of the anhydrous lithium iodide with low water content.

The utility model belongs to the technical field of lithium batteries, and particularly relates to a device for synthesizing anhydrous lithium iodide. Comprising a tubular reactor, a material processing tank and a vacuum dryer, one end of the tubular reactor is provided with a feed port, and the other end is provided with a discharge port; the material treatment tank is connected with the discharge port through a material flowing pipe, a filter membrane is detachably mounted in the material treatment tank, the top of the material treatment tank is connected with a feeder through a feeding pipe, and a first valve is arranged on the feeding pipe; and the vacuum dryer is connected to the bottom of the material treatment tank through a material outlet pipe. By adopting the tubular reactor, the reaction efficiency is effectively improved, and the tubular reactor has the characteristic of small backmixing, so that the volume efficiency (unit volume production capacity) is high, the reaction efficiency of lithium hydroxide and hydrogen iodide is accelerated, the problem of non-uniform concentration of a reaction system in the industrial production process of lithium iodide is avoided, and the product quality is improved. And meanwhile, the production efficiency of anhydrous lithium iodide is improved.

The application provides a solid-state electrolyte and application thereof, and the solid-state electrolyte at least comprises: a core body comprising a sulfide electrolyte; and a shell layer wrapped on the surface of the core body, and the shell layer comprises lithium iodide and lithium fluoride. Through the solid-state electrolyte and application thereof, the stability of the solid-state electrolyte to air and positive and negative electrodes can be improved, so that the cycle life and stability of the battery are improved.

A preparation method of lithium iodide and a solid-state battery, the preparation method comprising mixing a lithium source material, water, a first solvent and a quaternary amine base, reacting the quaternary amine base with carbon dioxide under a reaction atmosphere containing carbon dioxide to generate HCO3 ‑ , HCO3 ‑ reacting with lithium ions in the lithium source material to generate lithium bicarbonate, collecting an aqueous phase after the reaction; decomposing the lithium bicarbonate in the aqueous phase to generate lithium carbonate, collecting a solid phase, decomposing the lithium carbonate in the solid phase to generate lithium oxide to obtain an intermediate; dissolving a quaternary ammonium iodide salt in a second solvent and adding the intermediate, converting the lithium oxide into lithium hydroxide, and performing ion exchange between the lithium hydroxide and the quaternary ammonium iodide salt to generate lithium iodide, collecting a liquid phase; and collecting the lithium iodide in the liquid phase. Based on the characteristics of the specific quaternary amine base and the quaternary ammonium iodide salt, the application selectively enhances carbonization leaching of Li in the lithium source material, removes anion impurities in the lithium source material, and also realizes anion exchange in an organic phase and preparation of high-purity anhydrous lithium iodide.

The application belongs to the technical field of lithium metal batteries and photoelectrochemical energy storage, and discloses a starch-polyiodide composite solid electrolyte film and a preparation method thereof. The electrolyte film takes a polymer as a matrix, lithium bisfluorosulfonylimide and the like as a lithium salt, and a mixture of soluble branched starch, lithium iodide and iodine as a redox composite filler. Through the synergistic effect of the soft support effect of starch and the iodine-based redox pair, a uniform mixed conductive network is constructed, which can effectively reduce the interface impedance, inhibit the polymer crystallization, and significantly improve the ionic conductivity, lithium ion transference number and mechanical flexibility. The application further provides an integrated flexible photoelectrochemical energy storage battery device. The positive electrode-electrolyte integration is realized through an in-situ coating process, so that the device can still work stably under repeated bending and folding, and has high-efficiency light charging function, thereby providing a high-performance and high-safety solid electrolyte solution for the flexible light charging lithium metal battery.

The application discloses a glassy sulfide solid electrolyte with high lithium iodide content, a preparation method thereof and application of the glassy sulfide solid electrolyte in a full solid-state lithium metal battery. A synthesis procedure of the glassy sulfide solid electrolyte comprises a manual pre-grinding raw material procedure and a mechanical ball milling procedure. A general formula of the prepared glassy sulfide solid electrolyte is (0.65-x)((0.75+0.5y)Li2S-(0.25-0.5y)P2S5-yMS2)-(0.35+x)LiI, wherein x>=0, wherein y>0, and wherein M is a metal or a non-metal element in the fourth main group. The novel glassy sulfide solid electrolyte with high lithium iodide content has high ionic conductivity and good stability to metal lithium. The full solid-state lithium metal battery assembled by using the novel glassy sulfide solid electrolyte with high lithium iodide content has the characteristics of excellent cycle performance, high charge-discharge specific capacity and high safety.

This invention discloses a method for preparing a single-crystal lithium nickel manganese oxide cathode material with specific exposed crystal planes. The method involves adding a low eutectic point lithium salt system to alcohol for grinding, adding a nickel-manganese precursor, grinding and drying, sintering twice, centrifuging and washing, and vacuum drying to obtain the single-crystal lithium nickel manganese oxide cathode material with specific exposed crystal planes. The low eutectic point lithium salt system is a lithium salt composition capable of undergoing a eutectic reaction, including two of lithium hydroxide, lithium nitrate, lithium carbonate, lithium chloride, lithium bromide, lithium fluoride, lithium iodide, and lithium sulfate. The preparation method of this invention is applicable to preparing single-crystal lithium nickel manganese oxide cathode materials with (111), (110), and (100) planes as the main exposed crystal planes, resulting in significantly improved electrochemical cycle performance.

The invention provides a lithium ion battery, and belongs to the technical field of secondary batteries, the lithium ion battery is internally provided with a quenching device, and the quenching device comprises a container and a quenching agent. Wherein the quenching agent is packaged in the container, the quenching agent comprises a solvent and a quenching material dissolved in the solvent, the quenching material comprises lithium polysulfide and / or lithium polyiodide, the lithium polysulfide comprises Li2Sx, x is greater than or equal to 2 and less than or equal to 6, the lithium polyiodide comprises LiIy, and y is greater than or equal to 3 and less than or equal to 5. According to the lithium ion battery, the quenching device is arranged in the lithium ion battery, so that the thermal safety performance of the battery can be effectively improved on the premise of not increasing the internal resistance of the battery and not influencing the electrochemical performance of the battery.

The invention discloses a multi-reaction-mechanism positive electrode material as well as a preparation method and application thereof, and belongs to the technical field of preparation of aqueous zinc ion battery positive electrode materials. The preparation method disclosed by the invention comprises the following steps: adding layered vanadium oxide into deionized water, then adding iodide, and stirring to obtain a mixed solution; sequentially centrifuging, washing, drying and grinding the mixture to obtain the multi-reaction-mechanism positive electrode material; the layered vanadium oxide comprises vanadium pentoxide; the iodide is lithium iodide, zinc iodide, ammonium iodide, calcium iodide, sodium iodide or potassium iodide. According to the method, volume expansion and structure collapse caused by repeated embedding / removing of Zn < 2 + > in the circulation process are inhibited, and the stability is improved.

The invention belongs to the technical field of capacitors, and discloses a high-voltage fast-charging hybrid supercapacitor and a preparation method and application thereof. The hybrid supercapacitor comprises a positive electrode, a negative electrode, a diaphragm and an electrolyte, the positive electrode comprises a positive current collector and a positive active layer combined on the surface of the positive current collector, and the negative electrode comprises a negative current collector and a negative active layer combined on the surface of the negative current collector; the electrolyte comprises a molecular catalyst and a fluorine-containing organic solvent; the molecular catalyst comprises one or more of sodium iodide, sodium chloride, magnesium chloride, cobalt chloride, ammonium chloride, ammonium iodide, cobalt bromide, sodium bromide, aluminum bromide, lithium bromide, lithium iodide, zinc chloride and zinc iodide; the fluorine-containing organic solvent comprises a fluoro-carbonic ester organic solvent and / or a fluoro-ether organic solvent. The hybrid supercapacitor provided by the invention has the advantages of rapid charging and discharging capability, high working voltage, high energy density, high power density and excellent cycle life, and is suitable for higher energy storage and release requirements.

This invention discloses a method for preparing sulfur-containing ether compounds, comprising the following steps: in the presence of sodium hydride and lithium iodide, o-iodoaryl ether undergoes a coupling reaction with thiophenol or thiol to prepare the sulfur-containing ether compound. This invention prepares aryl sulfides from o-iodoaryl ether and thiophenol / thiol under NaH and LiI conditions. Compared with other conventional methods, this method does not require transition metal catalysis, has mild reaction conditions, and is simple to operate, providing a novel method for synthesizing sulfur-containing ether compounds with broad application prospects.

The invention discloses a solid-state electrolyte membrane and a preparation method thereof, and a solid-state lithium-sulfur battery based on the solid-state electrolyte membrane, the solid-state electrolyte membrane comprises a zinc sulfide layer, a lithium iodide intermediate layer and a lithium azide layer which are stacked in sequence, and the material for forming the zinc sulfide layer comprises a carbon material loaded with zinc sulfide. The material for forming the lithium iodide intermediate layer comprises a composite material formed by lithium iodide and sulfide solid electrolyte, the material for forming the lithium azide layer comprises a mixture of lithium azide and sulfide solid electrolyte, and through the arrangement of the three-layer structure, the solid electrolyte membrane with good ionic conductivity can be obtained; and the lithium-sulfur battery has good rate capability and capacity retention rate when being used in the lithium-sulfur battery.

The invention relates to a calcium iodide-based organic electrolyte, a secondary battery and a preparation method of the calcium iodide-based organic electrolyte, the electrolyte is composed of calcium salt, an organic solvent and an additive, the calcium salt is calcium iodide or a combination of calcium iodide and other calcium salt, the organic solvent is one or a combination of more of ether organic solvent, sulfone organic solvent, ester organic solvent, amide organic solvent, ionic liquid organic solvent and amine organic solvent; the additive is selected from one or more of lithium borohydride, sodium borohydride, potassium borohydride, zinc borohydride, magnesium borohydride, lithium iodide, sodium iodide, magnesium iodide, potassium iodide, tetraethyl ammonium borohydride, tetramethyl ammonium borohydride, benzyltriethyl ammonium borohydride and tetra-n-butylammonium borohydride. Compared with the prior art, the fluoride-free, thermodynamically stable and low-passivation-effect calcium iodide-based electrolyte provided by the invention can improve the interface property of a calcium metal negative electrode-electrolyte and increase the stability of the electrolyte, so that the cycle life of a calcium metal battery is prolonged, and the stability of the calcium metal battery is improved.

Provided is a lithium iodide nonaqueous solution containing a nonaqueous solvent and lithium iodide. This lithium iodide nonaqueous solution is characterized in that the water content per lithium iodide unit (Y / X), determined by the water content Y (ppm) in the lithium iodide nonaqueous solution relative to the lithium iodide concentration X (wt.%) in the lithium iodide nonaqueous solution, is 7 or less, and the content of an acid-derived component is 4,000 ppm or less.

The application provides an electrolyte applied to a lithium ferrous disulfide battery and a preparation method, the preparation method comprises the following steps: S1, dissolving lithium nitrate and lithium iodide in dioxolane (DOL), fully stirring to make them fully dissolved, and obtaining a first solution; S2, adding ethylene glycol dimethyl ether (DME) into the first solution, fully stirring until clear and transparent, and obtaining a second solution; S3, adding dimethylacetamide (DMAC) into the second solution, fully stirring until clear and transparent, and obtaining a finished electrolyte. The solvent dimethylacetamide (DMAC) with a high DN value is added, dioxolane (DOL) is made to form a thinner interface film to ensure the diffusion efficiency of lithium ions, and the activation energy required by a reaction is reduced by weakening the ferrous-sulfur bond, so that the discharge voltage and the discharge capacity of the lithium ferrous disulfide battery in a wider temperature range, especially at low temperature, are ensured, and the rate performance of the battery is improved.

The application provides a low-melting-point iodide modified lithium composite LATP solid electrolyte and a preparation method and application thereof, and belongs to the technical field of lithium battery solid electrolytes. The low-melting-point iodide modified lithium composite LATP solid electrolyte is prepared by the following steps: forming a modification layer on the surface of a LATP solid electrolyte sheet by drop coating an organic solution of antimony triiodide, tin tetraiodide or gallium triiodide on the surface of the LATP solid electrolyte sheet, and then reacting with molten lithium after heat preservation at 220-250 DEG C to form a lithiumophilic alloy and an iodine lithium composite interface layer. The lithiumophilic characteristics of antimony, tin and gallium in the iodide and the high ionic conductivity of lithium iodide are utilized to reduce the interface impedance of the LATP to 140-181 ohms, the initial overpotential is 63-71 mV, the 0.5 mAh / cm 2 The cycle time is more than 1200 h, and the problems of poor interface wettability, high interface impedance, Ti 4+ reduction side reaction and lithium dendrite growth existing in the prior art LATP solid electrolyte are effectively solved.

This invention belongs to the technical field of solid electrolytes and discloses a method for preparing a liquid-phase doped silver-germanium sulfide solid electrolyte with high ionic conductivity. The method includes: 1) dispersing lithium sulfide and phosphorus pentasulfide in an organic solvent, heating and stirring to obtain a precursor solution containing Li3PS4; 2) mixing lithium iodide, sulfur powder, and additives with the precursor solution, heating and stirring to remove the organic solvent, and obtaining a powder; 3) sintering the powder under a protective atmosphere to obtain a silver-germanium sulfide solid electrolyte; the additives are one or more of SiS2, GeS2, SnS2, As2S3, and Sb2S3. This invention is simple, and the prepared silver-germanium sulfide electrolyte undergoes elemental doping during thermal crystallization, improving the electrolyte's ionic conductivity and air stability. This method is suitable for industrial production.