2655 results about "Ionic conductivity" patented technology

The invention discloses a phosphonic acid-based metal organic framework solid electrolyte as well as a preparation method and application thereof, and belongs to the technical field of solid electrolyte materials. The method comprises the following steps: mixing a metal salt, an organic phosphonic acid ligand and an organic solvent, carrying out a coordination reaction, and treating to obtain MOF powder; heating and activating the MOF powder to obtain activated MOF powder; the method comprises the following steps: mechanically grinding lithium salt and MOF powder to form a mixture, heating to enable the molten lithium salt to permeate and fill MOF channels, and cooling to obtain solid electrolyte powder. The ionic conductivity of the solid electrolyte at 30 DEG C reaches 1.01 * 10 <-4 > S cm <-1 >, and the solid electrolyte is kept stable in a 4.4 V high-voltage window. The symmetrical battery based on the phosphonic acid-based MOF solid electrolyte can stably operate, and shows excellent compatibility and stability of the electrolyte and a lithium metal negative electrode. The method has the advantages of simple operation, cheap and easily available components, and is expected to be suitable for large-scale preparation.

The invention belongs to the technical field of solid-state lithium batteries, and relates to a fluorinated double-salt cross-linked solid-state electrolyte adaptive to a lithium-free negative electrode, a solid-state lithium battery and a preparation method thereof.The preparation method comprises the steps that double-lithium salt is dissolved in a fluorinated solvent to obtain an electrolyte, then a monomer, a cross-linking agent and an initiator are added, the mixture is stirred to be uniform to obtain a precursor solution, and the precursor solution is prepared; and assembling the precursor solution, a positive electrode, a negative electrode and a solid-state electrolyte composite diaphragm into a battery, and performing gradient polymerization to form the solid-state lithium battery. According to the invention, the ionic conductivity of the solid electrolyte is more than 5 * 10 <-4 > S / cm and the oxidation potential of the solid electrolyte is more than 5.8 V by adopting a fluorinated solvent consisting of fluorinated carbonate and fluorinated carboxylate and a double-lithium-salt synergistic system and combining an in-situ interface fusion technology, so that the solid electrolyte can be matched with a 4.8 V high-voltage lithium-rich manganese-based positive electrode and a lithium-free negative electrode; and the energy density and the safety of the solid-state lithium battery are improved. The electrolyte scheme is low in cost, high in safety and good in positive and negative electrode matching performance, can be compatible with an existing battery production line, and is convenient for large-scale production.

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 present disclosure provides a solid electrolyte composition that can suppress deterioration in ion conductivity of an ionic solid electrolyte material. The solid electrolyte composition according to the present disclosure contains a sulfur element-free ionic solid electrolyte material and an organic solvent, where the organic solvent includes at least one selected from the group consisting of a hydrocarbon and a compound having a functional group; and the functional group is at least one selected from the group consisting of an ether group, a halogen group, and a Si—O—C group.

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 present disclosure provides a solid electrolyte composition that can suppress deterioration in ion conductivity of an ionic solid electrolyte material. The solid electrolyte composition according to the present disclosure contains a sulfur element-free ionic solid electrolyte material and an organic solvent, where the organic solvent includes at least one selected from the group consisting of a hydrocarbon and a compound having a functional group; and the functional group is at least one selected from the group consisting of an ether group, a halogen group, and a Si—O—C group.

The invention provides an aerogel reinforced composite electrolyte thin film for a solid-state lithium battery and a preparation method of the aerogel reinforced composite electrolyte thin film, and belongs to the technical field of composite electrolytes.The thin film comprises a three-dimensional porous aerogel skeleton, a solid-state electrolyte compound and lithium salt nanocrystals; wherein the three-dimensional porous aerogel skeleton is prepared from inorganic oxide nanoparticles and a polymer precursor through a sol-gel method; pores of the three-dimensional porous aerogel skeleton are filled with the solid electrolyte compound, the solid electrolyte compound comprises lithium lanthanum zirconium oxide nanowires and a polyoxyethylene-lithium salt composite matrix, and the lithium lanthanum zirconium oxide nanowires are directionally arranged in the thickness direction of the film; the lithium salt nanocrystals grow on the surface of the pore wall of the three-dimensional porous aerogel in situ; the mass ratio of the aerogel skeleton to the solid electrolyte compound is (1: 3)-(1: 15). According to the thin film, the ionic conductivity, the mechanical strength and the interface stability of the electrolyte are remarkably improved.

The invention provides a surface-modified sulfide electrolyte and a preparation method thereof, and an all-solid-state battery, the surface-modified sulfide electrolyte comprises a sulfide electrolyte and a modification layer coated on the surface of the sulfide electrolyte, the chemical general formula of the modification layer is LiaMbNcXd, 0 < = a < = 3, 0 < = b < = 1, 0 < = c < = 1, 0 < = d < = 6, and 0 < = c < = 1. M is at least one element of magnesium, aluminum, calcium, iron, zirconium, niobium, tantalum, tungsten, gadolinium, yttrium, indium, hafnium, lanthanum and ytterbium, and X is at least one element of oxygen, sulfur, fluorine, chlorine, bromine and iodine. According to the surface-modified sulfide electrolyte, the modification layer with high ionic conductivity and high oxidation potential is coated outside the sulfide electrolyte, so that when the surface-modified sulfide electrolyte is applied to a positive electrode of an all-solid-state battery, the modification layer can improve the oxidation potential of the electrolyte on the premise of not reducing the ionic conductivity of the electrolyte; the effects of improving the interface stability between the positive electrode active material and the sulfide electrolyte and further improving the cycle performance of the battery are achieved.

The invention belongs to the technical field of solid-state batteries, and provides a lithium-sulfur-phosphorus-chlorine-bromine solid-state electrolyte, a preparation method thereof and an all-solid-state battery. The preparation method comprises the following steps: mixing lithium sulfide and phosphorus sulfide, and carrying out ball milling to obtain a lithium-sulfur-phosphorus ternary mixture; in protective gas, the lithium-sulfur-phosphorus ternary mixture, lithium chloride and lithium bromide are mixed and then subjected to ball milling, and a lithium-sulfur-phosphorus-chlorine-bromine mixture is obtained; and carrying out heat treatment on the lithium-sulfur-phosphorus-chlorine-bromine mixture in protective gas to obtain the lithium-sulfur-phosphorus-chlorine-bromine solid electrolyte. The lithium-sulfur-phosphorus-chlorine-bromine solid electrolyte provided by the invention not only improves the electrochemical stability, but also maintains the high ionic conductivity characteristic.

The invention discloses a lithium battery solid electrolyte interface film forming quality evaluation method. The method comprises the following steps: in a lithium battery formation stage or a circulation process, applying an alternating current disturbance signal with an amplitude of 1-20mV, and collecting full-band electrochemical impedance spectroscopy data in real time; a relaxation time distribution method is adopted to decouple the electrochemical impedance spectrum of the intermediate frequency region; constructing an equivalent circuit model containing SEI film characteristics, and fitting the decoupled electrochemical impedance spectrum curve by the equivalent circuit model; the compactness index of the SEI film is calculated according to the SEI film resistance and the film capacitance, and whether the compactness of the SEI film reaches the standard or not is judged according to the compactness index; and calculating a lithium ion diffusion coefficient by combining the charge transfer resistance and the Warburg diffusion impedance, and evaluating the SEI membrane ion transmission efficiency. According to the invention, non-destructive monitoring is supported, quantitative evaluation of SEI membrane compactness, ionic conductivity and short circuit faults in the module can be realized, and the cycle life and safety of the lithium battery are improved.

The invention discloses an oxyhalide solid electrolyte, a preparation method thereof and an all-solid-state battery, and relates to the technical field of batteries. The solid electrolyte is LiaMbNcXdOe, M and N are the same elements or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; x is at least one of F, Cl, Br and I. The oxyhalide solid electrolyte with high ionic conductivity and cost advantage is prepared by selecting high-valence metal oxide, halide and lithium halide through a ball milling method and combining annealing and hot pressing processes, and the oxyhalide solid electrolyte can show good electrochemical performance when being applied to all-solid-state lithium metal batteries.

The invention discloses a silicon-carbon composite negative electrode material, a negative electrode plate, a preparation method and application. The silicon-carbon composite negative electrode material is of a double-coating structure and sequentially comprises inner core silicon, a lithium phosphate layer and a fluorine-containing carbon layer from inside to outside, and the mass ratio of the lithium phosphate layer to the inner core silicon is (1-5): 100. When the composite material is applied to a lithium ion battery, the core silicon and the specific double coating layers can improve the fast charging performance and the first effect while optimizing an ion transmission path; a specific double-coating structure can be used as a buffer layer, stress generated by volume expansion of silicon can be released, and pulverization of particles is avoided; and moreover, LiF with high ionic conductivity and higher mechanical strength and an SEI film with more stable regulation and control are formed through reaction with an electrolyte, so that the structural integrity of the material is kept, and the cycle performance of the material is improved.

The invention discloses an artificial SEI material and a preparation method thereof, an artificial SEI film and an artificial SEI film modified negative electrode. The artificial SEI material is an organic polymer brush (CNF-g-PSSX) prepared by grafting cellulose nanofibers with polystyrene sulfonate. The polymer brush is of a crystal structure and has a firm framework; and the side chain of polystyrene sulfonate has rich-SO3 functional groups which are matched with cations in sulfonate, so that a rapid ion transmission channel is provided, high-current-density circulation can be realized, and good interface contact is ensured. Due to a special molecular topological structure and a multi-component synergistic effect, when the organic polymer brush forms an artificial SEI film, high mechanical strength, high ionic conductivity and low interface impedance can be obtained at the same time, and through strong electrostatic repulsion between a negatively charged-SO3 group and the surface of a negatively charged lithium dendrite tip, the electrochemical performance of the artificial SEI film is improved. An obvious inhibition effect is shown on the continuous growth of dendritic crystals.

The invention belongs to the technical field of batteries, and particularly discloses a secondary battery, a battery pack and an electric device. A negative electrode film layer of the secondary battery contains an additive; the additive comprises a carboxymethyl cellulose compound and a modified compound thereof; the compound is beneficial to improving the ionic conductivity of alkali metal ions and reducing the diffusion polarization phenomenon, so that the internal resistance of the battery is reduced. And the content of the additive in the negative electrode film layer close to the current collector is controlled to be higher than the content of the additive in the negative electrode film layer far away from the current collector, so that the technical effects of reducing the internal resistance of the battery, controlling the cost and reducing the influence on the energy density of the battery are achieved.

The invention relates to a composite diaphragm with high ionic conductivity, a composite solid electrolyte and a preparation method thereof. The composite diaphragm is composed of a lithium lanthanum-based fluorine-doped solid electrolyte LLMOF and a base membrane, the chemical general formula of the LLMOF is Li < x > La < y > M < 1 > < z > M < 2 > < w > M < 3 > O < 6 > F, wherein M1 is a tetravalent cation, M2 is a pentavalent cation, and M3 is a hexavalent cation; 1 < x + 3y < 5, 0 < x < = 2, and 1 / 3 < y < 5 / 3; 0 < = z < = 2, 0 < = w < = 2, 0 < = u < = 2, z + w + u = 2; the base membrane is a large-aperture base membrane, and the aperture r is more than or equal to 200nm and less than or equal to 1mu m; the particle size D50 of the LLMOF is 50 nm to 1 [mu] m, and the particle size D50 of the LLMOF is less than or equal to the aperture r of the base film. According to the composite diaphragm disclosed by the invention, the LLMOF solid electrolyte with an ion channel function is introduced, so that efficient conduction of ions is realized; the particle size is matched with that of a large-aperture base membrane, the membrane can be uniformly embedded into membrane holes, a continuous conduction path is constructed, and the ionic conductivity is improved; meanwhile, the composite diaphragm has excellent thermal stability and interface wettability, interface impedance is effectively reduced, and growth of lithium dendrites is inhibited.

The present invention belongs to the technical field of polymer binders, and particularly relates to a solid-state battery binder and a preparation method thereof, the solid-state battery binder comprises: a viscous monomer which is an acrylate monomer having a C3-C12 alkyl side chain; the lithium-supplying monomer is a monomer containing phosphate ester or a monomer which contains hydroxyl and amino and is easy to prepare phosphate ester through a phosphate esterification reaction; the lithium-conducting monomer is polyethylene glycol acrylate containing an ethyoxyl structure and a derivative of the polyethylene glycol acrylate; the adhesive monomer, the lithium-supplying monomer and the lithium-conducting monomer are polymerized together through a multifunctional integrated design, the adhesive has high solubility in an ester solvent due to a large number of ester groups contained in the adhesive, so that the bonding effect and the ionic conductivity of the solid-state battery can be improved, and the adhesive provided by the invention has high bonding force, and can be applied to the lithium-ion battery. The composite material has the advantages of high conductivity, high flexibility, high ionic conductivity, high solubility, high electrochemical stability, high temperature resistance and excellent comprehensive performance.

The invention relates to the technical field of batteries, in particular to a composite solid electrolyte material as well as a preparation method and application thereof. A composite solid electrolyte material comprises a base material and a composite coating layer located on the surface of the base material, the composite coating layer comprises a first coating layer and a second coating layer, the first coating layer is located on the surface of the base material, and the second coating layer is located on the surface of the first coating layer; the matrix material comprises a sulfide electrolyte material; the first coating layer is prepared from Li3PS4 and LiCl; the second coating layer contains LiF and LiPO4. According to the composite solid electrolyte material disclosed by the invention, the first coating layer (Li3PS4 and LiCl) and the second coating layer (Li3PS4 and LiCl) are arranged on the surface of the base material and are coordinated and matched, so that the composite solid electrolyte material has high ionic conductivity and high chemical and electrochemical stability.

The invention discloses a composite sulfide solid-state electrolyte and a preparation method and application thereof, and relates to the technical field of solid-state batteries. The composite sulfide solid electrolyte comprises sulfide solid electrolyte particles and nano ion conductor particles which are stable to water vapor, wherein the nano ion conductor particles are uniformly distributed on the surfaces and gaps of the sulfide solid electrolyte particles to form a composite structure. Therefore, through the composite structure that the nano ion conductor particles are uniformly distributed on the surfaces of the sulfide particles and in the gaps, the surface coverage of the sulfide solid electrolyte can be increased, the hydrolysis reaction rate can be reduced, and the sulfide solid electrolyte is well protected while the reduction amplitude of the lithium ion conductivity is reduced; the stability to air is improved; and the electrochemical stability is also improved. In addition, the method is simple in process, has good mass production capacity, and has high application value for actual production.

The invention belongs to the technical field of batteries, and particularly relates to a negative electrode material, a secondary battery and electric equipment. The second coating layer with the porous carbon material in the negative electrode material provides a sufficient buffer space for volume expansion of silicon, so that cracks and pulverization of the negative electrode material are effectively reduced, and the structural integrity of the negative electrode material is further ensured. And meanwhile, the solid electrolyte arranged in the second coating layer can maintain the smoothness of an ion transmission path in the silicon expansion process, so that the rate capability and the quick charge performance of the battery are ensured. Besides, a third coating layer (SEI film) formed by the ionic liquid has good ionic conductivity, and dynamic covalent bonds existing in some ionic liquids can be fractured and recombined under the action of external stress, so that a self-repairing function is realized. Therefore, when cracks are generated on the surface of the negative electrode material due to volume expansion, the third coating layer can quickly repair the cracks, prevent electrolyte permeation and lithium dendrite growth and inhibit side reactions.

The invention relates to the technical field of polymer photoelectric materials, in particular to a preparation method of a supramolecular gel electrolyte. The method comprises the following steps: esterifying tetraphenylethylene alcohol and methacryloyl chloride to form tetraphenylethylene methacrylate, and performing staged linear heating polymerization on the tetraphenylethylene methacrylate, 3-(methacrylamido) propyl dimethyl 3-thiopropyl ammonium oxide inner salt, acrylic acid, tetraphenylethylene methacrylate and 4-vinylpyridine under the action of ammonium persulfate to obtain a tetraphenylethylene copolymer. And finally, soaking in a lithium chloride aqueous solution to obtain the supramolecular hydrogel electrolyte. The hydrogel obtained by the invention has high mechanical strength and high ionic conductivity, and is suitable for energy storage devices such as flexible supercapacitors and the like.

The invention provides a composite sulfide solid electrolyte membrane, a preparation method thereof and a lithium ion battery. The composite sulfide solid electrolyte membrane comprises a halide layer and a sulfide layer which are sequentially arranged from top to bottom; the halide layer comprises a halide solid electrolyte material; the sulfide layer contains a sulfide solid electrolyte material with particle size grading, and sulfide particles with different particle sizes are uniformly mixed; a connecting surface is arranged between the sulfide layer and the halide layer, and the halide solid electrolyte material in the connecting surface is filled into a gap of the sulfide solid electrolyte material. The composite sulfide solid-state electrolyte membrane comprises the halide layer and the sulfide layer which are sequentially arranged from top to bottom, the compactness of the sulfide solid-state electrolyte membrane can be improved by grading sulfide solid-state electrolyte materials with different particle sizes, and a composite channel structure with high stability and high ionic conductivity is formed; the ion transmission efficiency and the interface long-term stability are both considered.

The invention relates to the technical field of lithium ion batteries, in particular to a diaphragm material for a lithium battery and a preparation method of the diaphragm material. Comprising a base film and a modified nano TiO2 coating, the modified nano TiO2 coating is arranged on at least one side surface of the base film, and the modified nano TiO2 coating comprises the following raw materials in parts by weight: 55-80 parts of a modified nano TiO2 composite material, 8-24 parts of a binder and 2.5-7.5 parts of a dispersant; the modified nano TiO2 composite material is prepared by taking cellulose nanocrystals, lanthanum zirconate and rare earth praseodymium as modifiers and nano TiO2 as a raw material, the mass ratio of the cellulose nanocrystal to the lanthanum zirconate to the rare earth praseodymium is (1-5): (2-3): 1. By adding the modified nano TiO2 composite material and introducing nano particles into the diaphragm, a three-dimensional network structure is formed, the liquid absorption property and the ionic conductivity of the diaphragm are improved, and meanwhile, the diaphragm is high in air permeability and relatively good in mechanical property and ionic conductivity.

The invention discloses a multi-layer composite thermal response battery diaphragm based on a basalt fiber reinforced substrate and a preparation method of the multi-layer composite thermal response battery diaphragm, and belongs to the technical field of lithium ion batteries. The diaphragm comprises the following structures: (a) a polypropylene (PP) matrix layer for providing electrolyte wettability and ionic conductivity; (b) the basalt fiber reinforced layer and the matrix layer are alternately overlapped, and the mechanical strength and the thermal stability of the diaphragm are remarkably improved through hot-pressing compounding; and (c) the intelligent temperature sensing hydrogel coating is formed by copolymerization of poly (N-isopropylacrylamide) (PNIPAm) and acrylamide (Am), reversible phase change of a temperature threshold of 50-70 DEG C is realized by adjusting a copolymerization ratio, an ion channel is closed at a high temperature to prevent thermal runaway, and ion conduction is recovered at a low temperature. The preparation method comprises the steps of material compounding, surface modification, hydrogel preparation, coating and the like. The lithium ion battery has excellent mechanical properties and a high-temperature self-protection function, and the safety and the reliability of the battery can be effectively improved.

The invention relates to the technical field of electrochemistry, and provides a sulfide solid electrolyte, a preparation method thereof, a battery and application. The chemical formula of the sulfide solid electrolyte is Li7-aPS6-aXa, X is halogen, and a is greater than or equal to 1 and less than or equal to 2; wherein the peak area of a diffraction peak corresponding to a (111) crystal plane of the sulfide solid electrolyte is I1, the peak area of a diffraction peak corresponding to a (311) crystal plane of the sulfide solid electrolyte is I2, and I1 / I2 is larger than or equal to 0.2 and smaller than or equal to 0.3. The I1 / I2 of the sulfide solid electrolyte disclosed by the invention is within the range, a good crystal structure and a relatively large interface area can be provided, and ion movement is promoted, so that relatively high ionic conductivity is obtained. Furthermore, according to the method disclosed by the invention, the high ionic conductivity of the product is ensured by reducing the solvent dosage and optimizing the sintering step, and meanwhile, the environmental pollution, the energy consumption and the production cost are remarkably reduced.

The invention provides an electrolyte for quickly charging a sodium-ion battery without a negative electrode. The electrolyte comprises a sodium salt, a solvent and an additive. According to the electrolyte, metal oxide nanoparticles are introduced as a first additive, and a second additive is supplemented, so that rapid desolvation of sodium ions on an electrode interface and improvement of the ionic conductivity of an electrolyte body are realized at the same time, and compact and dendrite-free sodium deposition under high current density is realized. The negative-electrode-free sodium-ion battery prepared from the electrolyte can be quickly charged, and good cycling stability and high capacity retention ratio can be maintained, so that the use requirements of people can be met.

The present invention belongs to the technical field of battery materials, and particularly relates to a composite phosphate-based positive electrode material, and a preparation method therefor and the use thereof. The composite phosphate-based positive electrode material comprises a phosphate-based active core, wherein the outer surface of the phosphate-based active core is sequentially coated with a carbon coating layer, a nitrogen-doped carbon coating layer and a nitrogen-phosphorus co-doped carbon coating layer from inside to outside, wherein the carbon coating layer can improve the electronic and ionic conductivity of the composite positive electrode material, and optimize the particle size and morphology of the composite positive electrode material. The nitrogen-doped carbon coating layer improves the consistency and integrity of coating; and nitrogen-atom-doped carbon further enhances the electronic conductivity and lithium-ion diffusion of the carbon coating layer. Electron-rich clouds of P and N atoms in the nitrogen-phosphorus co-doped carbon coating layer can provide a rich conductive network, mutual contact is formed among different particles to form a series network, thus promoting the interfacial electron transport of the composite material during a charging and discharging process, and improving the cycling and rate performance of the composite phosphate-based positive electrode material during the charging and discharging process.

The invention relates to a solid-state battery positive electrode material layer and a solid-state battery, belongs to the technical field of solid-state batteries, and is used for solving at least one of the problems that an existing solid-state battery is easy to crack, poor in contact and large in resistance, and a solid-state electrolyte battery prepared by a physical vapor deposition method is thin in electrode thickness, low in capacity and the like. A plurality of holes are formed in the positive electrode material layer, the diameter of each hole is 0.1-10 [mu] m, the opening area of each hole in the unit area of the positive electrode material layer accounts for 20-60% of the total area, and each hole is of a through hole structure. The positive electrode material layer of the solid-state battery is provided with a plurality of holes with through hole structures, the solid electrolyte is embedded into the holes, the holes are filled with the solid electrolyte, the solid electrolyte covers the positive electrode material layer, and the holes have specific diameters and opening areas, so that the ionic conductivity is improved, and the service life of the solid-state battery is prolonged. The thickness of the prepared positive electrode material layer can be designed as required.

The invention provides a positive electrode active material and a preparation method thereof, a positive electrode and a solid-state battery, and particularly relates to the technical field of solid-state batteries. The positive electrode active material has a core-shell structure, and the core-shell structure comprises a core layer and a coating layer coating the core layer; the core layer is made of a lithium-rich manganese-based material; and the coating layer is made of a fast ion conductor and a halide solid electrolyte. The fast ion conductor in the coating layer of the positive electrode active material can improve the ionic conductivity of the surface layer of the positive electrode active material, promote rapid migration of lithium ions and assist in improving the initial coulombic efficiency. Meanwhile, the coating layer improves the chemical stability of the positive electrode active material, effectively inhibits the interface side reaction between the positive electrode body and the sulfide electrolyte, and relieves the structural degradation in the cycle process. The coating layer can also be used as a buffer layer to inhibit stress generated by volume shrinkage and expansion in charge and discharge cycles, maintain good contact of an electrode interface, and realize improvement of the electrochemical performance of the material.

The invention relates to the technical field of lithium battery electrolytes, in particular to a preparation method of a polyether-based solid electrolyte and application of the polyether-based solid electrolyte in electrochemical devices such as lithium metal batteries. The polyether-based solid electrolyte material comprises a porous polymer skeleton, a cyclic ether monomer, a copper-based compound, a lithium salt and a plasticizing additive. The preparation method comprises the following steps: loading a copper-based compound into a porous polymer skeleton, adding cyclic ether, lithium salt and the like to carry out in-situ ring opening polymerization, cooperatively constructing a polyether-porous polymer skeleton three-dimensional network structure, and improving the mechanical strength of the electrolyte. Wherein the copper-based compound widens the chain spacing of the porous polymer, and is convenient for the cyclic ether monomer to penetrate into the skeleton; meanwhile, the in-situ ring-opening polymerization of the cyclic ether promotes the close contact between the electrolyte and an electrode, the interface impedance is reduced, and the ionic conductivity is improved. The polyether-based solid electrolyte prepared by the invention can promote stable circulation of a lithium metal battery.

The invention provides a non-aqueous electrolyte, a lithium ion battery, a battery module, a battery pack and an electric device. The non-aqueous electrolyte comprises a lithium salt, a non-aqueous organic solvent and a functional additive, and the functional additive comprises a bis-sulfinyl ester structure as shown in a formula I in the specification. When the non-aqueous electrolyte is used in the lithium ion battery, the wettability of the electrolyte can be effectively enhanced, the ionic conductivity of the electrolyte is improved, the low-temperature discharge capacity of the electrolyte is improved, and the stability of the electrolyte under high-temperature and high-voltage conditions is improved; and thus, the discharge capability and the service life of the lithium ion battery in high-temperature storage and high-temperature circulation are improved.