472 results about "Electrochemical window" patented technology

The invention provides a sodium ion battery electrolyte additive and a composition thereof, an electrolyte and a sodium ion battery containing the electrolyte. The additive is a fluorine-containing cyclic sulfate compound, the composition comprises fluorine-containing cyclic sulfate and other additives, and the fluorine-containing cyclic sulfate has a structure as shown in a formula (I): # imgabs0 # formula (I); the sodium-ion battery electrolyte comprises an organic solvent, a sodium salt electrolyte, the additive and any one composition of the additive, the sodium-ion battery comprises a positive electrode material, a negative electrode material and any one of the combined electrolyte. As the fluorine-containing additive has a relatively low HOMO energy level, the oxidation resistance of the non-aqueous electrolyte can be improved, and the electrochemical window of the non-aqueous electrolyte is widened; meanwhile, the cyclic sulfate participates in the formation of a negative electrode SEI film, so that the electrode interface is stabilized, and the impedance of the negative electrode surface can be remarkably reduced, thereby reducing the overall impedance of the battery, improving the rate capability and high-temperature performance of the battery, and prolonging the cycle life of the battery.

The invention relates to a high-voltage-resistant deep eutectic-based in-situ polymerization solid electrolyte as well as preparation and application thereof. The in-situ polymerization solid electrolyte is obtained through an in-situ polymerization reaction of a precursor solution comprising 30-80 wt% of a deep eutectic solution, 10-50 wt% of a polymerizable monomer, 1-30 wt% of an additive and 0.05-10 wt% of an initiator; the deep eutectic solution comprises a lithium salt and a hydrogen bond donor organic solvent; the hydrogen bond donor organic solvent comprises a nitrile solvent and a non-nitrile solvent; the polymerizable monomer comprises a monomer for free radical-initiated polymerization or ring-opening polymerization; the additive comprises lithium nitrate and fluoroethylene carbonate. The high-voltage-resistant in-situ polymerization solid electrolyte formed by in-situ compounding of an organic framework formed by in-situ polymerization of a deep eutectic solution, an additive and a monomer has the excellent characteristics of wide electrochemical window, high ionic conductivity, high mechanical strength, good flame retardance, wide-temperature applicability and the like, and can be suitable for a high-voltage system of 4.6 V or above; the solid-solid contact problem of a solid-state battery interface is effectively solved, and the side reaction between the electrolyte and the lithium metal negative electrode is reduced.

The invention discloses a difunctional filler synergistically enhanced polymer solid electrolyte and a solid-state battery, and belongs to the field of solid-state batteries. The electrolyte adopts a polymer matrix, a lithium salt and two functional fillers: the first filler has a high dielectric constant, and can accelerate dissociation of the lithium salt, fix negative ions of the lithium salt and improve the transference number of lithium ions under the action of self polarization; and the second filler has high electrochemical window and ionic conductivity, can inhibit high-voltage decomposition, and is adaptive to a high-voltage positive electrode material. Through cooperation and balance design of the two kinds of filler, ion transmission, interface stability and high-pressure compatibility can be considered at the same time. In addition, the invention further designs a composite negative pole piece, the surface of the negative pole piece is coated with the solid electrolyte, and the ion transmission kinetics in the pole piece can be remarkably improved. On the basis, the invention develops a high-performance solid-state battery which is excellent in electrochemical performance and can play an important role in the fields of consumer electronics, electric automobiles, energy storage systems, low-altitude flight and the like.

The invention discloses a solid electrolyte membrane and a preparation method and application thereof. The solid electrolyte membrane comprises a first electrolyte close to the positive pole piece and a second electrolyte layer close to the negative pole piece. The first electrolyte layer comprises a polymer, a lithium salt and an additive, and the second electrolyte layer comprises a solid electrolyte, a polymer, a lithium salt and an additive. The first electrolyte layer has a wide electrochemical window and relatively high mechanical properties, and can be matched with a high-voltage positive electrode material and improve solid-solid interface contact. The solid electrolyte of the second electrolyte layer is mainly composed of a continuous vertical array micro-mesoporous material, has a micro-mesoporous structure and high surface adsorption energy, and can accelerate lithium salt dissociation, reduce molecular interaction between polymer chains, form a three-dimensional continuous fast ion transmission channel and a heat conduction network, and improve ionic conductivity and safety performance. The solid electrolyte membrane disclosed by the invention has excellent ionic conductivity, wide electrochemical window, high safety performance and excellent electrochemical performance.

The invention discloses an alkali metal ion oxychloride-based solid electrolyte material and a solid-state battery, and belongs to the technical field of solid electrolyte. The chemical general formula of the solid electrolyte material provided by the invention is A < 2-2x > Zr < 1-x > M < 2x > Cl < 6-6x > O < 3x >, wherein A is an alkali metal element Li or Na; m is metal or lanthanide elements of In, Bi, Sb, Ce and La; x is more than 0 and less than or equal to 0.3. The oxychloride-based solid electrolyte is prepared by the following preparation method: respectively weighing precursor ACl, ZrCl4 and M2O3 (A = Li and Na, and M = In, Bi, Sb, Ce and La) powder materials according to the stoichiometric ratio of a general formula, and carrying out one-step high-speed ball milling, so as to prepare target solid electrolyte powder; the method is applied to solid-state batteries. The alkali metal ion oxychloride-based solid electrolyte shows the advantages of high ionic conductivity, wide electrochemical window, air stability, good deformability and the like in a solid-state battery, and has the advantages of low cost, simple synthesis process, easiness in condition control and the like.

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 an in-situ polymerized flame-retardant perfluorogel electrolyte, a lithium metal battery and a preparation method, the in-situ polymerized flame-retardant perfluorogel electrolyte is prepared from a fluorinated organic solvent, a lithium salt, a fluorine-containing polymer precursor and a thermal initiator, and the fluorine-containing polymer precursor further comprises a fluorine-containing polymer and a cross-linking agent. Compared with the prior art, the composite material has a high electrochemical window and excellent flame retardant property, and can realize matching with a high-voltage high-nickel positive electrode at room temperature and stable circulation of a high-voltage lithium metal battery; the preparation method is simple, the interface performance is optimized, and large-scale preparation is easy to realize.

The invention discloses a sulfide-based composite solid-state electrolyte, a preparation method thereof and a lithium metal solid-state battery, sulfide is subjected to specific bifunctional surface grafting modification by using a silane coupling reagent with sulfydryl and epoxy bonds, then the sulfide is introduced into a polymer precursor liquid, and the sulfide-based composite solid-state electrolyte is prepared through light-heat curing reaction synergy. A flexible and rigid cross-linked network is formed, the sulfide-based composite solid-state electrolyte with high ionic conductivity and high mechanical strength is obtained, the interface stability of the sulfide-based composite solid-state electrolyte in the charge-discharge process is ensured, for example, the sulfide-based composite solid-state electrolyte in the embodiment 1 has high ionic conductivity (3.81 mS / cm), and the interface stability of the sulfide-based composite solid-state electrolyte in the embodiment 2 is ensured. The lithium-lithium symmetric battery prepared by the method has the advantages of excellent flexibility, high tensile strength (7.9 Mpa) and wide electrochemical window (5.1 V), the lithium-lithium symmetric battery can stably circulate for 2000h, and the whole battery can stably circulate for 2000 circles at the room temperature at the rate of 4C, so that the lithium-lithium symmetric battery has great industrial application value.

The invention discloses a solid electrolyte with high ionic conductivity, which comprises the following components: a matrix material: a halide super ion conductor with a LiMXCl4 structure, M being selected from at least one of Ta, Nb and Hf, X being O or F, a chemical general formula being LiM1-aX1-6Cl4, a being equal to 0.1-0.3, and an electrochemical window being regulated to 2.5-4.0 V through fluorine-chlorine mixed anion substitution; the second phase material is a core-shell structure compound, the core is Li3TiCl6, and the shell is a Li3PS4 interface layer; and the sintering aid is a compound of Li3BO3 and LiF. Through fluorine-chlorine mixed anion regulation and control and MO2Cl4 octahedron synergistic tilting mechanism, the ionic conductivity of the solid electrolyte is remarkably improved, the lithium ion conductivity at room temperature is greater than or equal to 10mS / cm, the activation energy is less than or equal to 0.2 eV and is superior to that of the traditional halide electrolyte, and meanwhile, the free volume between chains is optimized through Zr < 4 + > / Sn < 2 + > gradient doping, so that the performance of the solid electrolyte is improved. The core-shell structure compound and the silane coupling agent are combined for modification, so that the electrochemical window is effectively widened to 2.5-4.0 V, the interface side reaction is inhibited, and the composite material is adaptive to a high-voltage positive electrode material.

The invention discloses a solid electrolyte, a preparation method thereof and an all-solid-state battery, and belongs to the technical field of solid electrolytes. According to the preparation method, a nano inert oxide and a solid electrolyte raw material are compounded through mechanical grinding, and the solid electrolyte with a core-shell structure is prepared; the device comprises an inner core, an interface layer and a shell from inside to outside, the inner core is a solid electrolyte matrix, the interface layer is a transition layer generated by reaction of the solid electrolyte matrix and a nano inert oxide, and the shell is a nano inert oxide layer. The material combines the advantages of high moisture resistance and wide electrochemical window of the nano inert oxide and the characteristics of high ionic conductivity and excellent mechanical property of the solid electrolyte, and the comprehensive performance of the material is remarkably improved through the synergistic effect of the components. The composite structure design not only solves the problem of performance limitation of a single material system, but also realizes collaborative optimization of ionic conductivity, environmental adaptability and electrochemical stability while ensuring the material stability.

The invention provides an electrolyte and a lithium battery containing the same. The electrolyte comprises a lithium salt, a solvent and an inducer, the solvent comprises one or more of siloxane compounds as shown in a formula I; the inducer is selected from one or more of C1-C5 halogenated alkanes, C1-C5 halogenated cycloalkanes, C2-C6 halogenated aliphatic ethers and C6-C12 halogenated aromatic compounds. The electrolyte provided by the invention utilizes the intermolecular interaction force between the siloxane compound and the inducer, so that the dissolution of the lithium salt in the solvent is realized, and the electrolyte has high compatibility to a lithium metal negative electrode, has a wide electrochemical window, can be well matched with a high-voltage positive electrode material and a lithium metal negative electrode material, and has a good application prospect. And the cycle life and coulombic efficiency of the battery can be improved.

The invention provides a composite sulfide solid electrolyte, a preparation method thereof and a lithium ion battery. The composite sulfide solid-state electrolyte comprises a sulfide solid-state electrolyte matrix and a composite layer coating the surface of the sulfide solid-state electrolyte matrix, the composite layer comprises an interface reaction layer and a coating layer from inside to outside, the coating layer comprises a halide material, and the interface reaction layer comprises an interface reactant obtained after the halide material and the surface of the sulfide solid electrolyte matrix are subjected to an interface reaction. According to the invention, under the action of the specific surface composite layer, the electrochemical window and mechanical property of the sulfide solid electrolyte are widened, the mechanical stability and electrochemical stability of the sulfide solid electrolyte and a positive electrode material are improved, and the interface reaction of the sulfide solid electrolyte is further inhibited.

The invention discloses a biosynthetic bacterial cellulose-based solid electrolyte as well as a preparation method and application thereof, and belongs to the technical field of solid electrolytes. The solid electrolyte is prepared by taking modified bacterial cellulose prepared by fermenting acetobacter xylinum, rhizobium, pseudomonas, azospirillum, alcaligenes and other bacteria as a substrate, introducing a low-molecular-weight polymer to regulate and control the arrangement of cellulose molecular chains to serve as a conductive ion framework, and then compounding a conductive ion high-molecular-weight polymer and a lithium salt. According to the invention, cellulose molecular chains are modified by modified glucose, and a network structure is regulated and controlled by a low-molecular-weight polymer, so that the problems of small spacing, lack of ion coordination sites and weak ion transmission capability of pure cellulose molecular chains are effectively solved, the ionic conductivity of the prepared solid electrolyte can reach 10 <-4 > S cm <-1 >, the electrochemical window width reaches 5V, and the solid electrolyte has a good application prospect. The material can tolerate high critical current density, is suitable for various positive electrode materials, and is suitable for high-voltage and long-cycle-life energy storage devices.

The invention relates to an organic solid electrolyte for an in-situ curing high-voltage positive electrode, a battery and a preparation method. The organic solid electrolyte is formed by in-situ polymerization of ether monomers, ester monomers, a lithium salt and a solvent through synergistic thermal initiation of double initiators. The electrolyte disclosed by the invention has the advantages that the ester polymer monomer and the ether polymer monomer are blended, and then the two monomers are respectively polymerized in a thermal initiation manner to form mutually crossed macromolecular long chains. The strategy can improve the interface stability of the electrode and the electrolyte and reduce the interface impedance of the electrode and the electrolyte. In the formed polymer network structure, the ester chain segment enhances the mechanical strength and widens the electrochemical window; and the ether chain segment provides flexible and lithium ion transmission channels. Due to the chemical complementarity of the ester monomers and the ether monomers, the overall performance of the composite polymer electrolyte is improved.

The invention discloses electrolyte for a long-service-life sodium-ion battery as well as a preparation method and application of the electrolyte, and relates to the technical field of sodium-ion battery electrolyte. According to the invention, the piperidinyl and phosphorous acid tetrafluoroborate ionic liquid is added, so that the performance of the sodium ion electrolyte is remarkably improved. Firstly, the additives improve the thermal stability and chemical stability of the electrolyte, which are particularly important in the long-term operation process of the battery, and can effectively prevent the electrolyte from being decomposed under high-temperature or extreme operating conditions. And secondly, because the ionic liquid has excellent electrochemical stability, the electrochemical window of the electrolyte is enhanced due to the existence of the ionic liquid, that is, the electrolyte can bear a wider voltage range without electrochemical reaction. This is very advantageous for improving the energy density and power output of the battery. And finally, the introduction of the ionic liquid can also increase the ionic conductivity of the electrolyte and reduce the internal impedance of the battery, so that the charge-discharge efficiency and the cycle life of the battery are improved.

The invention relates to the field of battery materials, in particular to a halogen-free electrolyte for a magnesium metal battery and a preparation method of the halogen-free electrolyte. The magnesium salt comprises at least one of bis (trifluoromethanesulfonyl) imide magnesium and magnesium trifluoromethanesulfonate; the additive is prepared from at least one of indole, 3-azaindole, 4-azaindole, 5-azaindole, 6-azaindole, 4-amino indole, 5-amino indole, 6-amino indole and 7-amino indole; the organic solvent comprises ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1, 3-dioxolame or 1, 3-dioxane. The preparation method comprises the following steps: sequentially adding the magnesium salt and the additive into the organic solvent, and stirring and reacting at room temperature for 1 min to 24 h to obtain the halogen-free electrolyte for the magnesium metal battery. And the prepared electrolyte has excellent performances of small overpotential, long service life and wide electrochemical window, and has a good commercial application prospect.

The present invention relates to an in-situ synthesized high-voltage resistant gel polymer electrolyte, belonging to the technical field of gel polymer electrolytes. The electrolyte is prepared by the following method: in a light-proof protective gas atmosphere with oxygen and water contents less than 1 ppm, PETT and divinyl adipate are added to an electrolyte in a substance ratio of 1: (1-4) to obtain a mixed solution a, wherein the concentration of PETT is (0.2-5) mol / L, and then a free radical polymerization photoinitiator is added and mixed to obtain a mixed solution b, and bubbles in the mixed solution b are removed to obtain a precursor solution; the precursor solution is used to infiltrate the positive electrode material in the positive electrode for 0.5h-2h, and then visible light is used for irradiation for 0.2h-1h to obtain the electrolyte on the positive electrode. The electrolyte has good ionic conductivity and lithium ion migration number, and has a wide electrochemical window, and has good interface compatibility with the positive electrode.

The invention discloses a preparation method of a composite solid electrolyte membrane, and belongs to the technical field of solid lithium batteries, the composite solid electrolyte membrane is formed by uniformly stirring and compounding a polymer matrix, a lithium salt, an inorganic filler SiO2 aerogel and a solvent, the ionic conductivity of the membrane can be effectively improved by modifying the molecular structure of a polymer, and the ionic conductivity of the membrane can be effectively improved by using the SiO2 ceramic inorganic filler. The mechanical strength of the composite solid electrolyte membrane is improved; the prepared composite solid electrolyte membrane is good in electrochemical performance, the room-temperature ionic conductivity can reach 2.3 * 10 <-4 > S / cm, the lithium ion transference number can reach 0.78, the composite solid electrolyte membrane has a wide electrochemical window, the preparation process of the composite solid electrolyte membrane is simple, the stability of an interface between the composite solid electrolyte membrane and a positive electrode and a negative electrode of a battery is good, and the composite solid electrolyte membrane can be applied to the field of lithium ion batteries. The assembled total battery has good cycle stability, and the capacity retention rate can reach 82.3% after 400 cycles.

The invention provides a composite solid electrolyte membrane, a preparation method thereof and a solid lithium metal battery. The preparation method comprises the following steps that an organic-inorganic composite membrane is provided, the organic-inorganic composite membrane comprises organic components and inorganic components, and the organic components comprise polysulfone organic matter; and soaking the organic-inorganic composite membrane in a salt solution, and drying to obtain the composite solid electrolyte membrane. According to the invention, the polysulfone organic matter with high dielectric strength is introduced into the organic-inorganic composite membrane, so that the electrochemical window of the composite solid electrolyte membrane is remarkably improved, and the normal work of the battery in a relatively high voltage range is ensured.

The invention provides a polymer electrolyte with high interface stability and a preparation method and application thereof. The polymer electrolyte comprises a polymer matrix, a porous support material, a lithium salt, a solvent and an initiator. The polymer matrix is formed by in-situ copolymerization of a methacrylate polymer monomer as a rigid skeleton monomer and a methacrylate polymer monomer with a functional group as a functional monomer. The polymer electrolyte prepared by an in-situ curing method has high room-temperature ionic conductivity, a wide electrochemical window (gt; 5.3 V) and excellent cycling stability. The functional monomer is helpful for forming a high-stability SEI film rich in inorganic components on a positive electrode and a lithium metal / electrolyte interface, the stability of the electrode / electrolyte interface is improved, and the growth of lithium dendrites is inhibited, so that the mechanical property and the safety performance are improved. The polymer electrolyte can be widely applied to battery systems such as high-voltage lithium ion batteries, high-specific-energy lithium ion batteries and high-safety lithium ion batteries.

The invention discloses a fast-charging lithium ion battery electrolyte, a preparation method thereof and a lithium ion battery containing the fast-charging lithium ion battery electrolyte. The fast-charging lithium ion battery electrolyte comprises the following components: electrolyte salt, an organic solvent and an electrolyte additive, the electrolyte additive comprises a first additive and a second additive; the first additive is a multi-element sulfate ester additive, and the mass percentage of the multi-element sulfate ester additive is 0.05%-2% based on the total mass of the electrolyte being 100%. By adding the polybasic sulfate additive with a specific structure, adopting a composite solvent system and cooperating with the synergistic effect of other additives, lithium salt and other components, dual stability of positive and negative electrode interface films is realized, the electrochemical window of the electrolyte is widened, and the thermal stability and cycling stability of the electrolyte are improved; and finally, the battery has the advantages of fast charging capability, high voltage compatibility, long cycle life and high thermal safety at the same time.

The invention discloses a multi-layer electrolyte membrane for a solid-state battery and a preparation method thereof, and the multi-layer electrolyte membrane comprises a first layer membrane which has oxidation resistance and is used for contacting with a high-nickel positive electrode material; the second layer of film comprises a porous lining body, a sacrificial additive is stored in the porous lining body, and the sacrificial additive can be released in the cycle process of the battery; and the third-layer film has reduction resistance and is used for being in contact with a lithium metal negative electrode material. According to the invention, the electrolyte membrane with a multi-layer structure is constructed, an oxidation-resistant polymer is used for the positive electrode, and a reduction-resistant polymer is used for the negative electrode. The polymer solid electrolyte with a wide electrochemical window is constructed and can be matched with a high-nickel positive electrode and a lithium metal negative electrode at the same time.

The invention discloses an imidazolium ionic liquid modified magnesium ion battery electrolyte and a preparation method and application thereof. The imidazolium ionic liquid modified magnesium ion battery electrolyte is obtained by fully dissolving [EOE-A-Im] [TFSI] ionic liquid in an APC electrolyte. Wherein [EOE-A-Im] [TFSI] is a 1-allyl-3-(2-ethoxyethyl)-1H-imidazole-3-onium bis (trifluoromethylsulfonyl) imine salt, and APC is a total phenyl complex. The imidazolium ionic liquid modified magnesium ion battery electrolyte disclosed by the invention is relatively wide in electrochemical window, excellent in compatibility with electrodes, high in magnesium deposition-dissolution efficiency, low in overpotential and good in cycling stability; and the preparation method of the imidazolium ionic liquid modified magnesium ion battery electrolyte is simple and environment-friendly, and accords with green industrial production.

The invention provides a solid electrolyte and a preparation method thereof, a diaphragm, a battery and power-related equipment, and relates to the technical field of lithium batteries. The solid electrolyte is of a core-shell composite structure with LATP as a core and Mg-Sn alloy as a shell wrapping the outer surface of the core. According to the solid electrolyte with the core-shell structure, the LATP serves as the core, the Mg-Sn alloy serves as the shell, air stability is enhanced, Li2CO3 impurities are prevented from being generated, high ionic conductivity and a wide electrochemical window are kept, and stability and mechanical strength are improved. The corrosion resistance and tear resistance of the alloy enhance the safety of the battery, and the aluminum element in the LATP improves the strength of the alloy and optimizes the performance and charge-discharge efficiency of the battery.

The invention belongs to the technical field of polymer electrolyte membrane materials, and particularly relates to a high-ionic-conductivity polymer electrolyte membrane and a preparation method thereof.The preparation method comprises the steps that 1, PEO and lithium salt are added into a polar aprotic solvent, and the mixture is rapidly and violently stirred to be completely dissolved; (2) adding a cross-linking agent and a photoinitiator into the mixed solution, and violently stirring to obtain a mixed solution; and (3) coating the mixed solution in a polytetrafluoroethylene template, heating to remove the solvent, and performing ultraviolet radiation. According to the invention, a three-dimensional cross-linked network is formed by photocuring of an acrylate group of the cross-linking agent, PEO chain segment crystallization is inhibited, and lithium salt anions (such as TFSI-) are physically embedded. A benzene ring structure in a cross-linked network endows the electrolyte membrane with flexibility, mechanical property deterioration caused by a plasticizer or a diluent is avoided, the compact structure of the electrolyte membrane can inhibit lithium dendrite growth, the ionic conductivity reaches 1.7 * 10 <-4 > S / cm, and the electrochemical window reaches 4.9 V. The method is simple in process and suitable for large-scale preparation of the high-energy-density solid-state lithium battery.

The invention discloses a lithium metal battery eutectic gel electrolyte and a preparation method and application thereof, and belongs to the field of solid electrolyte. The eutectic gel electrolyte is prepared by carrying out a photocuring reaction on a photocuring precursor solution containing a photoinitiator, and the photocuring precursor solution contains a bi-component liquid compound and a deep eutectic solvent; the two-component liquid compound comprises 4-acryloyl morpholine and a photocurable polyethylene glycol derivative; the deep eutectic solvent is formed from a liquid mixture comprising succinonitrile, lithium bis (trifluoromethylsulfonyl) imide and fluoroethylene carbonate. The eutectic gel electrolyte is composed of a deep eutectic solvent with functional groups such as cyano and sulfonyloxy, and a polymer electrolyte with functional groups such as ether oxygen and a unique skeleton structure. The advantages of high ionic conductivity, wide electrochemical window, high interface stability and the like can be endowed based on the interaction between functional groups and the space confinement effect of a polymer electrolyte skeleton structure.

According to the high-temperature lithium ion battery electrolyte and the lithium ion battery containing the high-temperature lithium ion battery electrolyte, tris (trimethylsilane) phosphate, 2-(3-(trifluoromethyl)-1H-pyrazol-1-yl) acetonitrile and 1, 2, 3-trifluorobenzene are selected as additives in the electrolyte, and the three components can synergistically improve the high-temperature stability of the electrolyte, so that the high-temperature stability of the electrolyte is improved; and gas generated by thermal decomposition and side reaction is reduced, so that the risk that the internal pressure of the battery is abnormally increased or the battery swells due to the gas generated by the electrolyte in the high-temperature long-term storage process is reduced. Meanwhile, the influence of impurities in the electrolyte can be reduced, an electrochemical window is improved, the stability of the electrolyte can be kept at high temperature, and the service life of the battery can be prolonged.

The invention provides a modified positive electrode material and a preparation method and application thereof. The modified positive electrode material comprises a lithium manganese iron phosphate inner core and a coating layer coating the surface of the lithium manganese iron phosphate inner core, and the material of the coating layer comprises oxyfluoride; ti and S are co-doped in the lithium manganese iron phosphate core. Ti and S are co-doped in a lithium manganese iron phosphate core, Ti doping can introduce additional electron holes to enhance the intrinsic electron conductivity of the material, S doping can expand a lithium ion channel and improve the Li < + > diffusion rate, and the Ti doping and the S doping are synergistically optimized through two channels of electron conduction-ion migration, so that the rate capability and the cycling stability of the positive electrode material are improved; the oxyfluoride is adopted as a coating layer material, so that HF corrosion and dissolution of transition metal can be reduced, an interface side reaction is inhibited, meanwhile, the excellent thermal stability and wide electrochemical window of the oxyfluoride can inhibit decomposition and gas production of an electrolyte in a high-temperature environment, and the thermal stability and electrochemical stability of the modified positive electrode material are improved.

The invention discloses a novel polymer solid electrolyte with a wide electrochemical window and a preparation method thereof.The preparation method comprises the steps that a quinoline compound and metal sodium react for a certain time, and a 4, 4 '-biquinoline intermediate product is obtained after separation; carrying out monosubstitution reaction on the obtained 4, 4 '-biquinoline intermediate product and brominated alkane, then adding bromoethylene to carry out disubstitution reaction, then adding divinyl ether to carry out addition reaction, and then adding an aqueous solution containing fluorine anions to carry out anion exchange reaction to obtain an olefin-terminated biquinolinium compound; mixing the MOF material with graphene oxide, and carrying out cross-linking reaction on the obtained olefin-terminated biquinolinium compound in a nitrogen environment to prepare an MOF composite material; in an inert atmosphere, PNIPAM and the MOF composite material prepared in the step 3 are subjected to a reaction, and the thermal response self-adjusting composite electrolyte is prepared; and adding a catalyst and a lithium salt into the obtained composite electrolyte, and heating and curing to obtain the polymer solid electrolyte with the wide electrochemical window.

The invention discloses a nanofiber membrane material for a solid polymer electrolyte as well as a preparation method and application of the nanofiber membrane material. The nanofiber membrane material is prepared from the following raw materials: an electrostatic spinning fiber membrane and a polymer matrix, the polymer matrix comprises a polymeric monomer, a lithium salt and an initiator; the polymeric monomers comprise polyethylene glycol diacrylate and trifluoroethyl methacrylate. The room-temperature ionic conductivity, the electrochemical window and the high-temperature mechanical property of the nanofiber membrane material disclosed by the invention are all at relatively high levels in the field of solid polymer electrolyte, and the nanofiber membrane material is easy to prepare and assemble into a battery.