4946 results about "All solid state" patented technology

The invention discloses a composite polycrystalline positive electrode material which is prepared by permeating and coating a polycrystalline positive electrode material with an oxyhalide solid electrolyte, and the oxyhalide solid electrolyte comprises one or more of Li-Ta-O-Cl, Li-Nb-O-Cl, Li-Zr-O-Cl and Li-Al-O-Cl. The specific oxyhalide electrolyte is adopted to carry out permeation coating on the polycrystalline positive electrode material, uniform coating on the surface of the polycrystalline positive electrode material and grain boundaries in particles is completed, capacity utilization in the particles of the polycrystalline positive electrode material is achieved, and the capacity utilization rate of the particles of the polycrystalline positive electrode material is improved through the coating effect of the oxyhalide with high ionic conductivity. Ion transmission inside and in gaps of the polycrystalline positive electrode material particles is regulated, interface impedance is reduced, energy density is improved, and the application prospect is wide.

The invention provides an all-solid-state battery, a preparation method thereof and electric equipment. The all-solid-state battery comprises a positive plate, a negative plate and an electrolyte layer positioned between the positive plate and the negative plate, the positive plate comprises a positive current collector layer and a positive active material layer, one side of the positive active material layer is coated with an insulating layer at an interval, and the circumferential edge of the negative plate is in lap joint with the insulating layer. The all-solid-state battery can improve the insulation performance in the using process, and the effect of reducing the risk of short circuit is achieved.

The invention relates to a method for preparing lithium sulfide, which comprises the following steps: respectively dissolving a sulfur source compound and a lithium source compound in alcohol under the protection of inert atmosphere, and then mixing the two alcohol solutions for double decomposition reaction to generate a lithium sulfide suspension; and then carrying out evaporative crystallization, supercritical fluid washing, centrifugal separation and freeze drying treatment to obtain a lithium sulfide product. The purity of the lithium sulfide prepared through the method can reach 99.9% or above, the lithium sulfide can be used as a positive electrode material of a lithium-sulfur battery or a raw material of a sulfide solid electrolyte in an all-solid-state battery, and the method is low in energy consumption, conforms to the concept of green chemistry and is suitable for large-scale industrial production.

The present invention relates to an all-solid-state battery (ASSB) comprising: an anode comprising a first solid electrolyte; a cathode composite comprising a second solid electrolyte, a solid electrolyte selected from the first and second solid electrolytes, and at least one buffer layer in contact with a surface of the solid electrolyte, where when the solid electrolyte is the first solid electrolyte, one buffer layer is at an interface of the electrolyte with the cathode, and when the solid electrolyte is the second solid electrolyte, one buffer layer is at least one of the first solid electrolyte and the second solid electrolyte. And when the solid electrolyte is a second solid electrolyte, a buffer layer is at the interface of the electrolyte and the anode, where the first electrolyte is selected from a sulfide solid electrolyte and a lithium oxide solid electrolyte, where the second electrolyte is a halide solid electrolyte, and where the buffer layer has a thickness of from 0.5 nm to less than 10 nm. The invention also relates to an anode assembly, a cathode assembly and an electrolyte assembly comprising at least one buffer layer. The invention also relates to a method for producing an ASSB or component according to the invention, in which the buffer layer is deposited by a vapor deposition-based method.

The invention discloses an all-solid-state battery cell as well as a preparation method and application thereof, and relates to the technical field of solid-state batteries. The cured insulation paste is attached to the edge of the positive electrode active layer, the size difference between the positive electrode active layer and the negative electrode active layer is supplemented through the cured insulation paste, the ends of the positive electrode active layer and the negative electrode active layer are flush, the insulation paste plays a supporting role under extrusion, and the problems of collapse, short circuit and the like caused by the size difference between the positive electrode active layer and the negative electrode active layer are avoided; the insulation paste at the edge can be bonded with the negative electrode under a high pressure condition, so that when the positive electrode is charged and discharged, the problem of poor cycle performance caused by volume change of the positive electrode plate in the charging and discharging process can be effectively relieved, and the cycle performance of the battery is improved; and the problems of material falling at the edge of the positive pole piece and the like can be effectively avoided. The electrolyte membrane is arranged between the positive active layer and the negative active layer, and the ionic liquid treatment layer on the electrolyte membrane is utilized, so that the impedance between the electrolyte membrane and the pole piece is reduced, and the battery performance is improved.

The invention relates to the technical field of solid-state batteries, in particular to oxyhalide solid-state electrolyte as well as a preparation method and application thereof. The method comprises the following steps: taking molten salt LiaMbXc as a raw material, reacting with an oxide AdOf in a molten state, removing steam impurities by utilizing a high-temperature vacuumizing mode, and cooling to prepare the oxyhalide solid electrolyte; according to the invention, the molten salt raw material is molten at high temperature to form the ion melt, and the oxygen element is introduced to replace part of halogen, so that the hardness of the target electrolyte is reduced after cooling, the deformability at room temperature is improved, and the obtained electrolyte is high in conductivity and wide in antioxidant electrochemical window. The prepared oxyhalide solid electrolyte is used for preparing a positive electrode, the adhesion force between the electrolyte and positive electrode material particles, the actual microscopic contact area and the ion migration rate are improved through melt permeation, the problem of a positive electrode interface is effectively relieved, and the electrochemical performance of an all-solid-state battery is improved.

The invention relates to a composite solid electrolyte membrane with high ceramic content and a preparation method and application thereof. The preparation method comprises the following steps: mixing ceramic solid electrolyte particles activated by a silane coupling agent with an in-situ polymerization solution containing a cross-linking agent, an organic monomer, a plasticizer, a lithium salt, an ultraviolet light initiator and a thermal initiator to form solid electrolyte slurry, wherein the ceramic solid electrolyte particles account for 60-90% of the total mass of the composite solid electrolyte membrane; the preparation method comprises the following steps: coating a positive pole piece with solid electrolyte slurry, initiating shallow organic matter monomers and a cross-linking agent to generate in-situ polymerization through an ultraviolet light initiator, covering a negative pole piece for hot pressing treatment, initiating residual organic matter monomers and the cross-linking agent to generate in-situ polymerization through a thermal initiator, and forming a composite electrolyte membrane with high ceramic content. The invention also discloses an all-solid-state battery containing the composite solid electrolyte membrane. The solid-state battery containing the in-situ formed composite solid-state electrolyte membrane has relatively high cycling stability.

The invention discloses a single-ion conductor polymer, a ternary composite binder solution, high-solid-content sulfide electrolyte slurry and a wet film forming method and application thereof, and belongs to the technical field of all-solid-state lithium batteries. The key technical problems in the wet membrane preparation of the sulfide electrolyte are solved through an innovative solvent-binder synergistic system, and the method specifically comprises the steps that 1, through the synergistic effect of a non-polar solvent and a weak-polar solvent, low-viscosity coating of high-solid-content slurry is achieved while the chemical stability of the sulfide electrolyte is guaranteed; 2, a poly (lithium styrenesulfonate-butyl acrylate), styrene butadiene rubber and polyisobutene ternary composite binder is designed, a lithium ion transmission channel is provided through a lithium sulfonate group, a benzene ring structure in the styrene butadiene rubber enhances the mechanical strength, long-chain alkane in the polyisobutene improves the interface adhesive force, and the mechanical strength is improved; the three components cooperate to realize balance of mechanical and electrochemical properties of the electrolyte membrane, so that the prepared electrolyte membrane has low porosity, high ionic conductivity and mechanical strength.

The invention relates to the technical field of solid electrolyte, and discloses a double-layer solid electrolyte membrane, a preparation method thereof and an all-solid-state battery. The double-layer solid-state electrolyte membrane comprises a first solid-state electrolyte layer and a second solid-state electrolyte layer which are overlapped with each other, the first solid-state electrolyte layer comprises hydride solid-state electrolyte, and the second solid-state electrolyte layer comprises halide solid-state electrolyte; the hydride solid electrolyte comprises Li < 7-a > P (BH4) S < 6-a > and / or Li < 7-a-b > P (BH4) S < 6-a-b > X , a < = 2, 0lt; blt; 2. The interface between the double-layer solid-state electrolyte membrane and the positive electrode and the interface between the double-layer solid-state electrolyte membrane and the negative electrode have good interface stability, and the interface side reaction between the two solid-state electrolyte layers is less, so that the solid-state battery has high coulombic efficiency and cycling stability.

The invention discloses a preparation method and application of a sulfide solid electrolyte membrane based on a gradient polymer / ionic liquid composite binder, and an all-solid-state battery, and belongs to the technical field of all-solid-state batteries. The method comprises the following steps: firstly coating a polymer / ionic liquid / sulfide electrolyte composite layer through a gradient coating process, filling particle gaps under low pressure by utilizing the plasticizing effect of ionic liquid, and reducing the porosity of an interface; and then coating a polymer / sulfide electrolyte surface layer to provide mechanical support and inhibit side reaction of the electrode. According to the design, the electrolyte membrane still keeps high ionic conductivity under the working pressure of a commercial power battery module, and the interface impedance is reduced compared with that of a traditional homogeneous membrane. Through the innovative gradient structure and material combination, the ion transmission bottleneck of the sulfide electrolyte under the low-pressure condition is solved, excellent interface stability and process compatibility are achieved, and a key technical scheme is provided for all-solid-state battery industrialization.

The invention relates to the technical field of blood potassium detection, in particular to a blood potassium detection paper-based sensor and a preparation method and application thereof.The sensor is obtained by integrating a substrate, a sensing electrode and a whole blood microfluid channel, and the sensing electrode is located between the substrate and the whole blood microfluid channel; the whole blood microfluid channel comprises a serum diffusion area, a whole blood separation area positioned above the serum diffusion area and a blood potassium detection area positioned below the serum diffusion area; a blood separation membrane is also arranged in the whole blood separation area; the substrate is qualitative filter paper, and the sensing electrode comprises an all-solid-state PBA working electrode and an Ag / AgCl reference electrode; compared with the prior art, calibration is not needed when potassium ions in whole blood are detected, the whole blood sample can be directly used, centrifugal separation is not needed, the detection speed is increased, the hemolysis problem of the whole blood sample in blood potassium detection can be avoided, and the detection sensitivity, accuracy and stability are further improved.

The invention belongs to the technical field of new energy, and discloses a preparation method and application of a LiaMXb-based composite solid electrolyte membrane, and the preparation method comprises the following steps: S1, carrying out spray drying on a mixed solution in which a Li source, an M source and an ammonium salt are dissolved, placing the mixed solution in a crucible of which the bottom is paved with the ammonium salt, and annealing for 2-10 hours at 350-800 DEG C in an inert atmosphere to obtain a LiaMXb solid electrolyte; s2, mixing the LiaMXb solid electrolyte with a fluorine-containing monomer A and a dispersing agent, and performing spray drying to obtain electrolyte powder wrapped by the fluorine-containing monomer A; s3, ball-milling and uniformly mixing the electrolyte powder wrapped by the fluorine-containing monomer A, a lithium salt, a thermal curing agent and a monomer B in an inert atmosphere to obtain composite electrolyte powder; and S4, carrying out cold isostatic pressing and hot pressing curing on the composite electrolyte powder to prepare the LiaMXb-based composite solid electrolyte membrane. The prepared LiaMXb-based composite solid electrolyte membrane not only has excellent air stability, flexibility and machinability, but also has a continuous three-dimensional ion conduction path, and the assembled all-solid-state lithium battery has good electrochemical performance.

The invention relates to the technical field of all-solid-state lithium metal batteries, in particular to a cellulose paper-based polymer solid electrolyte as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing N-methylacetamide and lithium bis (trifluoromethanesulfonyl) imide to obtain a eutectic solvent; the preparation method comprises the following steps: mixing a eutectic solvent, polyethylene glycol oxalate, acrylamide and a thermal initiator to obtain a eutectic polymer electrolyte precursor; and soaking cellulose paper in the eutectic polymer electrolyte precursor, and carrying out hot-pressing polymerization to obtain the cellulose paper-based polymer solid electrolyte. The cellulose paper-based polymer solid electrolyte prepared by the invention is soft in texture and can be better attached to an electrode, the problem of poor contact between the electrode and an electrolyte interface is solved, and the interface impedance is reduced by fusing the characteristics of low viscosity and high conductivity of the eutectic solvent and the supporting effect of the cellulose paper; the ion transmission efficiency is improved, and conditions are provided for long-term stable circulation of the battery.

The invention provides a positive pole piece, a preparation method thereof and a sulfide all-solid-state battery. The positive pole piece comprises a positive current collector and a positive material layer arranged on the surface of the positive current collector, the positive electrode material layer comprises a modified positive electrode active material, an antioxidant, a sulfide electrolyte material, a conductive agent and a positive electrode binder, the modified positive electrode active material comprises an inner core and an oxide coating layer arranged on the surface of the inner core, and the inner core is a lithium-containing positive electrode active material. When the positive electrode plate containing the antioxidant and the modified positive electrode active material provided by the invention is applied to the sulfide all-solid-state battery, the synergistic effect of the antioxidant and the modified positive electrode active material can be exerted, so that the rate capability and the cycling stability of the sulfide all-solid-state battery are improved.

The invention provides a high-performance all-solid-state sodium ion battery, and belongs to the technical field of power batteries, the sodium ion battery comprises a Prussian white positive electrode, a metal sodium negative electrode and an NASICON type solid electrolyte; preparation raw materials of the Prussian white positive electrode comprise Prussian white, the general formula of the Prussian white is NaxFe [Fe (CN) 6], and x is larger than or equal to 1.8 and smaller than 2.2; the composition of the NASICON type solid electrolyte is NaxZr2-yMySiuPvO12, x is more than 0 and less than or equal to 4, y is more than or equal to 0 and less than 2, u is more than 0 and v is less than 3; in the NaxZr2-yMySiuPvO12, M is at least one of a Zn element, a Mg element, a Cu element, an Al element, a Ni element, a Ga element, a Fe element and a K element. The sodium ion battery has excellent electrochemical performance at room temperature, is high in safety, and is beneficial to commercialized development and application of all-solid-state sodium ion batteries. The invention also provides a preparation method of the high-performance all-solid-state sodium ion battery.

The disclosed subject matter relates to lithium ion conductors and batteries (such as pseudo solid state and all solid state batteries), and methods of making and use thereof. Disclosed herein are lithium ion conductors comprising Li1+xNb1−xZrxOX4, wherein X is a halide; and 0≤x≤1. Also disclosed herein are methods of making and use of any of the lithium ion conductors (e.g., Formula I) disclosed herein. Also disclosed herein are devices comprising any of the lithium ion conductors disclosed herein (e.g., Formula I), such as a solid state battery.

The invention relates to a solid electrolyte coated silicon-carbon negative electrode material and a preparation method thereof, an all-solid-state battery and an electric device, and belongs to the technical field of methods or devices for directly converting chemical energy into electric energy. The solid electrolyte coated silicon-carbon negative electrode material comprises a silicon-carbon negative electrode material and a solid electrolyte coating layer arranged on the surface of the silicon-carbon negative electrode material, the solid electrolyte coating layer comprises at least one of sulfide electrolyte and halide electrolyte; the silicon-carbon negative electrode material comprises an inner core and a carbon coating layer arranged on the surface of the inner core, the inner core comprises a porous carbon matrix and a silicon-based material positioned in pores of the porous carbon matrix. The solid-state electrolyte coated silicon-carbon negative electrode material enables an all-solid-state battery to have high ionic conductivity and first efficiency and excellent cycling stability.

The invention belongs to the technical field of design and preparation of solid electrolyte materials, and particularly relates to a LiBH4-based composite solid electrolyte material and a preparation method thereof.The LiBH4-based composite solid electrolyte material is obtained by performing high-energy ball milling on a mixture of LiBH4 and one or two metal halides MX2 in a certain molar ratio in an argon atmosphere; m is Mg, Zn, Ni or Bi; x is F, Cl, Br or I. According to the LiBH4 composite solid electrolyte prepared by the preparation method disclosed by the invention, the ionic conductivity at room temperature is improved to 10 <-4 > S cm <-1 > or above, and the ion diffusion activation energy is only 0.16 eV; the process is simple, the preparation time is short, the repeatability is high, no pollution is caused to the environment, and the industrial production requirement is met, so that the all-solid-state lithium ion battery electrolyte is expected to realize commercialized application.

The invention discloses a composite solid electrolyte membrane, a solid lithium metal battery and a preparation method thereof, the composite solid electrolyte membrane comprises a fast ion conductor filler, a PVDF polymer matrix, a lithium salt and an amide additive, and the amide additive can perform weak coordination with lithium ions. According to the composite solid-state electrolyte membrane, the solid-state lithium metal battery and the preparation method of the solid-state lithium metal battery, disclosed by the invention, the room-temperature ionic conductivity of all-solid-state composite electrolyte can meet room-temperature operation of the battery, and the solid-state lithium metal battery is suitable for large-scale production and application.

The invention relates to the technical field of solid-state electrolytes, and discloses a high-ionic-conductivity solid-state electrolyte, a preparation method thereof and a solid-state battery. The preparation method comprises the following steps: mixing lithium sulfide, lithium chloride, lithium oxide, phosphorus pentasulfide and boron nitride in an inert atmosphere to obtain a mixture; carrying out ball milling on the mixture to obtain precursor powder; and sintering the precursor powder, and dispersing the sintered precursor powder to obtain the high-ionic-conductivity solid electrolyte. The boron element, the nitrogen element and the oxygen element are introduced into a lithium phosphorus sulfur chlorine system as doping elements, lattice parameters of LPSC are changed through the boron element, the rotation rate of a PS4 / BS4 tetrahedron is enhanced, and a lithium ion diffusion channel is optimized, so that the lithium ion transition activation energy of the electrolyte is reduced, the migration rate of lithium ions is increased, and the performance of the electrolyte is improved. Therefore, the solid electrolyte has high ionic conductivity. The introduced nitrogen element and oxygen element can interact with atoms such as sulfur and phosphorus, the electron cloud distribution of anion groups is adjusted, the interaction energy of lithium ions and the anion groups is reduced, the lithium ion transmission performance is further improved, and the electrochemical stability of the anion framework is enhanced. This makes it possible to increase the energy density of an all-solid-state battery when used in a solid-state battery.

The invention relates to the technical field of solid electrolyte, in particular to normal-temperature surface modified flexible oxide solid electrolyte and a preparation method and application thereof. The normal-temperature surface-modified flexible oxide solid electrolyte is prepared from the following raw materials: a monomer, polyethylene oxide, a solvent, an initiator, a modified oxide ceramic electrolyte and electrolyte salt, wherein the mass of the monomer is 1-10% of the total mass of the components; the molar ratio of the initiator to the monomer is 0.01%-0.1%; the molar ratio of the electrolyte salt to the monomer is 1: (6-12); the mass ratio of the electrolyte salt to the modified oxide ceramic electrolyte is 1: (2.5-5). The flexible oxide solid electrolyte has high conductivity, wide temperature tolerance range and high structural stability, and when the flexible oxide solid electrolyte is applied to an all-solid-state lithium metal battery, the ionic conductivity, safety and cycle performance of the battery are improved.

The invention relates to the technical field of all-solid-state batteries, in particular to a halide sulfide double-layer coated positive electrode material and a preparation method and application thereof. The halide sulfide double-layer coated positive electrode material comprises a positive electrode material substrate, and a halide electrolyte coating layer and a sulfide electrolyte coating layer which sequentially coat the positive electrode material substrate. The halide electrolyte coating layer is located in the middle layer, compatibility with a positive electrode interface can be achieved by means of high oxidation resistance of the halide electrolyte coating layer, and the problem of the positive electrode interface occurring in sulfide electrolyte oxygenolysis is solved. The sulfide electrolyte coating layer is located on the outermost layer, air stability is excellent, processing in a dry environment can be met, and the problems that halide electrolyte is poor in chemical stability, cannot be processed and manufactured in an external environment and is high in density are solved. The halide sulfide double-layer coated positive electrode material has high interface stability and good chemical stability.

The invention belongs to the related technical field of all-solid-state lithium metal batteries, and relates to a prediction method and system for cavity evolution in an all-solid-state lithium metal battery, and the method comprises the following steps: carrying out grid division on a lithium metal electrode, enabling grid nodes to be lithium atoms or vacancies, applying a stacking pressure from bottom to top at the bottom of the lithium metal electrode, meanwhile, the working temperature and the stacking pressure of the computational domain are changed, so that the size of the cavity is adjusted; constructing a phase-field sequence parameter equation, a concentration equation, an electrochemical equation and a mechanical equation for describing cavity evolution; and establishing an optimization model with the minimum cavity area as a target, solving the optimization model, and obtaining a relationship between the stacking pressure and the working temperature and the cavity area, so as to realize prediction of cavity evolution. According to the invention, quantification of cavity evolution in the all-solid-state lithium metal battery under different stacking pressures and different working temperatures is realized.

The invention discloses a composite coated graphite negative electrode material, a preparation method thereof and a lithium ion solid-state battery, and belongs to the technical field of lithium ion solid-state batteries, the composite coated graphite negative electrode material comprises a graphite matrix and a composite coating layer, and the composite coating layer comprises an inner layer amorphous lithium chloride and an outer layer nanocrystalline LiF / Li3N composite phase. Mixing graphite, lithium chloride containing crystal water and ammonium fluoride to obtain a mixed material; placing the mixed material in a microwave reaction cavity, heating the mixed material to 600-700 DEG C at the microwave power of 800-1200 W in an H2 / Ar mixed atmosphere, and keeping the temperature for 20-60 minutes; and cooling the sintered mixed material, grinding, and sieving with a 100-300 mesh sieve to obtain the composite coated graphite negative electrode material with a coating layer thickness of 10-50 nm. The invention provides an innovative amorphous LiCl / nanocrystalline LiF-Li3N gradient coating layer design, the performance of the lithium ion battery is remarkably improved by optimizing an ion migration path, enhancing the interface stability and reducing the process cost, and a new engineering way is provided for realizing high magnification and long cycle performance of the sulfide all-solid-state battery.

The invention relates to the field of batteries, in particular to an all-solid-state thin film battery and a preparation method thereof. The all-solid-state thin film battery comprises a positive electrode current collector layer, a positive electrode layer, a solid electrolyte layer, a negative electrode layer and a negative electrode current collector layer, the thicknesses of the positive electrode layer and the solid electrolyte layer are 10 nm to 50 [mu] m, and the positive electrode layer is made of a material which contains a sulfur element and has the capacity of storing and discharging electricity; when the positive electrode layer is made of a material which contains a sulfur element and a metal element and has electricity storage and discharge capabilities, the thickness of the negative electrode layer is 0 nm to 50 [mu] m; when the positive electrode layer is made of a material which contains a sulfur element and has electricity storage and discharge capabilities, the thickness of the negative electrode layer is 10nm-50mu m; the thickness of the positive electrode current collector layer is 10 nm to 100 [mu] m; and the thickness of the negative current collector layer is 0 nm to 100 [mu] m. According to the invention, the cost of the battery can be effectively reduced, the capacitance of the battery is improved, and large-area and mass production of the battery can be realized.

The present invention relates to a positive electrode for an all-solid-state battery, the positive electrode comprising a positive electrode active material, a sulfide-based solid electrolyte, a conductive material, and a binder, the sulfide-based solid electrolyte comprising a first sulfide-based solid electrolyte containing a bromine (Br) element and a second sulfide-based solid electrolyte not containing the bromine (Br) element, the positive electrode active material comprising a core capable of reversibly absorbing and releasing lithium ions; and a coating layer formed on a surface of the core, the coating layer comprising the first sulfide-based solid electrolyte, and the all-solid-state battery comprising the positive electrode.

The invention provides a sulfide solid electrolyte as well as a preparation method and application thereof. The molecular formula of the sulfide solid electrolyte is Li P < 1-b > M S < c > O < d > X < e >, wherein: 5lt; a < lt >; 6; 0 lt; blt; 1; 1.5 1t; clt; ct; 5, 0lt; dlt; 2.5, 4lt; c + dlt; 5, 1lt; lt, lt; 2; m is selected from one or more of Al, Ga, In, Ti, Sc, As, Sb, Bi, V or Nb; x is selected from one or more of Cl, Br or I. According to the sulfide solid electrolyte and the preparation method and application thereof, the stability of the conductivity of the sulfide solid electrolyte can be improved, the air stability is enhanced, the electrolyte / active substance interface property is improved, the service life of an all-solid-state lithium ion battery is prolonged, and the safety of the all-solid-state lithium ion battery is improved.

The present disclosure belongs to the technical field of all-solid-state batteries. Provided are a sulfide solid electrolyte membrane and a preparation method therefore, and an all-solid-state alkali metal ion battery. The sulfide solid electrolyte membrane is composed of sulfide particles containing a polymer coating, and the chemical composition of the sulfide particles containing a polymer coating is [EmMnSo]CαOβSγHδNζEa.

A preparation method for a battery positive electrode material, a battery positive electrode, and an all-solid-state battery. The preparation method for a battery positive electrode material comprises: dissolving a sulfide solid-state electrolyte in an organic solvent to form a solution; and dispersing a positive electrode active material into the solution, and then carrying out drying treatment, to obtain a battery positive electrode material in which the positive electrode active material is coated with the sulfide solid-state electrolyte. The preparation method can increase the contact area between the solid-state electrolyte and the positive electrode active material, effectively solves the problem of small interfacial contact area between conventional solid-state electrolytes and positive electrode active materials, and thus enhances the capability of ions to rapidly intercalate into or deintercalate out of positive electrode active materials and facilitates transport of ions and utilization of capacity.

The invention discloses a modified lithium borohydride solid electrolyte and a preparation method thereof, and belongs to the field of all-solid-state battery electrolyte preparation, the method comprises the following steps: mixing LiBH4 and lithium halide according to a formula ratio, and carrying out ball milling and heating to obtain an xLiBH4-LiX (x = 1-5) solid solution; then mixing and ball-milling B2O3 and the LiBH4-lithium halide solid solution to obtain a doped and composite synergistically modified (xLiBH4-LiX) y-B2O3 (y is equal to 10 to 20) solid electrolyte; a LiBH4 phase is stabilized by doping lithium halide, and grain gaps are densified by compounding B2O3, so that the grain boundary impedance is reduced, the lithium dendrite inhibition capability of the lithium borohydride-based solid electrolyte is improved, the stable operation of the lithium borohydride-based solid electrolyte at high voltage is ensured, and the lithium borohydride-based solid electrolyte has relatively high ionic conductivity, relatively low electronic conductivity and a relatively wide electrochemical window; and the lithium borohydride-based solid electrolyte has good stability and compatibility with a lithium metal negative electrode, and development of the lithium borohydride-based solid electrolyte in commercial application of a lithium ion battery is facilitated.