18results about How to "Reduce Shuttle Effect" patented technology

The invention discloses a preparation method and application of a two-dimensional composite material. The preparation method comprises the following steps: adding MXene into formamide, carrying out ultrasonic dispersion to obtain an MXene formamide dispersion liquid, then adding MgAl LDH into the MXene formamide dispersion liquid, carrying out magnetic stirring, washing with absolute ethyl alcohol, and carrying out vacuum drying to obtain a two-dimensional composite material which is marked as MgAl LDH / MXene. The two-dimensional composite material is used for a lithium-sulfur battery diaphragm barrier layer so as to inhibit the shuttle effect of polysulfide. The preparation method is simple and environment-friendly, and the prepared MgAl LDH / MXene two-dimensional composite material is high in specific surface area, has strong affinity to polysulfide, can promote rapid transmission of lithium ions, can provide an instant electron conduction way for adsorbed polysulfide, is applied to a diaphragm barrier layer of a lithium-sulfur battery, and has a good application prospect. The wettability of the electrolyte on the diaphragm and the conversion of polysulfide are enhanced, the problem of volume expansion in the cycle process of the lithium-sulfur battery is relieved, and the redox reaction kinetics is accelerated.

The invention relates to the technical field of lithium-sulfur batteries, in particular to a preparation method of an MOF (Metal Organic Framework)-based lithium-sulfur battery diaphragm material, which starts from the aspect of diaphragm modification of a lithium-sulfur battery, and integrates another metal into a Cr-MOF framework as a diaphragm coating material of the lithium-sulfur battery through a simple solvothermal method. A channel of a three-dimensional structure is composed of ordered micropores, the average size of the channel is smaller than the diameter of lithium polysulfide, and catalytic conversion of lithium polysulfide adsorbed in a lithium-sulfur battery can be achieved through multiple introduced metal active sites while the shuttle problem of lithium polysulfide is solved, so that accumulation of lithium polysulfide is reduced, and the utilization rate of an active material is increased; according to the MOF-based diaphragm disclosed by the invention, firstly, the shuttle effect of lithium polysulfide can be obviously reduced;

The invention discloses a preparation method and application of a high-entropy catalyst tellurium-selenium tungsten molybdenum sulfide, and belongs to the technical field of energy materials, the preparation method comprises the following steps: adding selenium powder into a hydrazine hydrate solution to form a solution A; dissolving sodium molybdate dihydrate, tungsten chloride and thiourea in the reduced graphene oxide suspension to form a mixed solution B; the solution A and the solution B are mixed together and stirred to obtain a solution C, and the solution C is transferred into a high-pressure kettle for a hydrothermal reaction; washing a product obtained by the reaction with deionized water, and freeze-drying after washing to obtain a black product A; and putting the product A at a leeward position of a tubular furnace, putting tellurium powder at a windward position of the tubular furnace, and performing annealing treatment in an argon-hydrogen environment to obtain the tellurium-selenium tungsten-molybdenum sulfide catalyst. According to the preparation method and application of the high-entropy catalyst tellurium selenium tungsten molybdenum sulfide, rapid transmission of electrons is facilitated, the transmission efficiency of ions and electrons is improved, and the dynamic performance of a battery is enhanced.

The present invention relates to the field of electrochemical energy storage technology, specifically to an amine carbon-loaded aqueous sulfur-based battery positive electrode material and its preparation method and application, wherein an active substance is anchored by carbon-sulfur bonds on a hydrophilic carbon-based material through a solution thiamine synthesis scheme, and a sulfur component is loaded through a high-temperature melting process under an inert atmosphere to form a high-stability sulfur-based battery positive electrode material. The material can effectively limit the soluble intermediates generated during the discharge process to the positive electrode side to slow down the shuttle effect of polysulfides, thereby enhancing the long cycle life of aqueous sulfur-based batteries, and exhibits excellent rate performance in aqueous sulfur-based batteries.

The invention relates to the technical field of energy storage batteries, in particular to a positive electrode material for a liquid metal battery, a preparation method of the positive electrode material and the liquid metal battery, the positive electrode material is an alloy composed of tellurium and a transition metal element, the chemical formula of the alloy is TenX1-n, X is the transition metal element, n is the molar percentage of tellurium in the alloy, and n is the molar percentage of tellurium in the alloy. N is more than 50% and less than 100%, the transition metal element is one or more of Cr, Mn, Fe, Co, Zn, Cd, Rh and Pd, the solubility of Te in the molten salt electrolyte is effectively inhibited by adding the transition metal element, and the coulombic efficiency and cycling stability of the liquid metal battery are improved.

The invention belongs to the field of lithium-sulfur secondary batteries, and relates to a high-performance lithium-sulfur battery, the high-performance lithium-sulfur battery comprises a sulfur-carbon positive electrode, a lithium negative electrode, an electrolyte and a diaphragm, the diaphragm comprises a base membrane and a functional coating coated on one or two surfaces of the base membrane, and the functional coating comprises molybdenum disulfide particles coated with metal molybdenum nanoparticles. The application of molybdenum disulfide particles coated with metal molybdenum nanoparticles to the functional layer of the lithium-sulfur battery diaphragm is proposed for the first time, so that the shuttle effect of polysulfide can be effectively inhibited, the redox reaction of the polysulfide can be accelerated, the polysulfide is promoted to be quickly converted into solid Li2S, the utilization rate of sulfur is increased, the accumulation of intermediate products is reduced, and the service life of the lithium-sulfur battery diaphragm is prolonged. The coulombic efficiency and the cycling stability of the battery are improved; and the two are combined to form an efficient conductive network, so that the conductivity is remarkably improved, rapid transmission of electrons in the conductive network is promoted, and the rate capability of the battery is improved.

This invention provides a lithium titanium dioxide sodium phosphate anode material and an aqueous lithium-iodine battery based thereon, belonging to the field of secondary battery technology. The chemical formula of the lithium titanium dioxide sodium phosphate anode material is Li. x Na y Ti2(PO4)3, where 0

The invention discloses a preparation method of a positive electrode material, the positive electrode material and a lithium-sulfur battery, and the preparation method of the positive electrode material comprises the following steps: pretreating a carbon nanotube to obtain an open carbon nanotube; the method comprises the following steps: putting an open carbon nanotube into a container, and vacuumizing the container until the vacuum degree is 0.05-0.1 Pa; keeping the vacuum degree, and injecting a metal catalyst solution into the container to soak the open carbon nanotubes to obtain a precursor mixture; the precursor mixture is dried and subjected to heat treatment, the metal catalyst is converted into metal particles, the opening carbon nanotubes are filled with the metal particles, and a carbon nanotube composite material is obtained; and adding sulfur into the carbon nanotube composite material, grinding and heating to obtain the positive electrode material. According to the present invention, the metal catalyst is efficiently coated with the carbon nano-tube through the negative pressure liquid phase method, such that the catalytic activity and the stability of the catalyst are improved, the shuttle effect in the lithium-sulfur battery is reduced, and the long-term effect and the stability of the positive electrode material are improved.

The invention relates to an iodine-containing acetonitrile electrolyte for a high-energy-density battery as well as a preparation method and application of the iodine-containing acetonitrile electrolyte, and belongs to the technical field of aqueous zinc-iodine batteries. The iodine-containing acetonitrile electrolyte for the high-energy density battery comprises a zinc salt, iodine acetonitrile and deionized water. Compared with a traditional zinc-iodine battery which only depends on iodine positive electrode oxidation reduction, the battery prepared from the iodine-containing acetonitrile electrolyte for the high-energy-density battery in the invention has the advantages that the iodine-containing acetonitrile electrolyte for the high-energy-density battery can be subjected to auto-oxidation reduction in the charging and discharging process, and the multi-iodide shuttle effect is reduced; therefore, the corrosion to the negative electrode is reduced and the battery capacity is remarkably improved. In addition, different from a multi-electron transfer type high-energy-density zinc ion battery, the iodoacetonitrile does not provide an additional redox platform, but enhances the I-I0 reaction through a special channel of self-redox of an electrolyte medium.

The present application provides a manganese sulfide-molybdenum disulfide heterojunction lithium-sulfur battery positive electrode host material, with molybdenum disulfide nanosheets as the main body, and manganese sulfide nanoparticles are anchored on the molybdenum disulfide nanosheets to form a composite material with a manganese sulfide-molybdenum disulfide heterostructure. The present invention adds manganese disulfide tetrahydrate, anhydrous sodium molybdate and thioacetamide into ultrapure water, stirs at room temperature, and reacts by hydrothermal method to obtain a manganese sulfide-molybdenum disulfide heterojunction composite material. The preparation process of the present invention is short and the process is simple, and the experimental repeatability is good. The prepared manganese sulfide-molybdenum disulfide heterojunction composite material has high electronic conductivity, high catalytic activity for polysulfur intermediate species, and strong chemical adsorption for polysulfides, which effectively alleviates the shuttle effect and improves the kinetics of the electrode reaction process.

The application discloses a preparation method of single-atom modified porous carbon material and application of the single-atom modified porous carbon material in lithium-sulfur batteries. The preparation method comprises the following steps: preparing zinc-based metal organic framework material Zn-MOF nanoparticles; coating phenolic resin (RF) on surfaces of the Zn-MOF nanoparticles to obtain Zn-MOF-RF nanoparticles; adsorbing X metal salt on the Zn-MOF-RF nanoparticles by using a solution immersion method; and obtaining X single-atom loaded hollow nitrogen-doped porous carbon (X-N / HNPC) composite material by high-temperature carbonization under an inert atmosphere. The composite material has a large specific surface area and rich pore size structure, and as a positive electrode material, can not only improve the utilization rate of active material sulfur, but also effectively adsorb polysulfides by high catalytic active sites, improve redox reaction kinetics, and further inhibit the shuttle effect of polysulfides. Based on the lithiumophilicity of metal single atoms, as a lithium negative electrode carrier, the lithium uniform deposition can be regulated, the growth of lithium dendrites can be relieved, and the stability of the battery can be improved.

The invention relates to the technical field of lithium batteries, and discloses a carbon-coated composite nickel cobalt lithium manganate lithium battery, which is prepared by the following steps: selecting 3 parts of steady-state nickel powder, 5 parts of steady-state manganese powder, 1 part of steady-state drilling powder, 1 part of carbon material and solvent; particularly, a mixture formed by mixing steady-state nickel-cobalt-manganese powder, vertical array-shaped carbon nanotubes and mesoporous carbon according to the mass ratio of 10: 1 is selected as a lithium material in a positive electrode to prepare positive electrode mixed slurry, so that the carbon-coated battery negative electrode material has more excellent performance, and meanwhile, the optimal selection of the negative electrode material is matched; according to the lithium ion battery, the shuttle effect and dendritic crystal growth in the continuous charging and discharging process can be effectively weakened, the lithium ion battery shows better cycle performance, rate performance and safety performance compared with conventional metal lithium, then the carbon-coated nickel-cobalt-manganese composite material is used as a positive active material, and a mixture formed by combining ketjen black and nano carbon according to the mass ratio of 1: 3 is used as a conductive agent, so that the lithium ion battery is prepared. A mixed system formed by mixing polyvinylpyrrolidone and polyethyleneimine according to the volume ratio of 2: 1 is used as a binder.

This invention belongs to the field of functional material preparation, and particularly relates to a flake-like MoO2. 2 / Mo 2 C@poplar catkin biomass carbon composite material and its application: scaly MoO2 was prepared by a method of poplar catkin carbonization-impregnation with molybdate-calcination in an inert atmosphere. 2 / Mo 2 C@poplar catkin biomass carbon composite material, and further calcined the material in air to prepare hollow tubular MoO 3 The materials and synthesis methods are simple and easy to implement. The materials obtained in this invention exhibit excellent performance as anode materials for lithium-ion batteries and cathode carrier materials for lithium-sulfur batteries, which is beneficial for the preparation of high-energy-density electrode materials. Moreover, the preparation method is inexpensive and can simultaneously solve the harm caused by poplar catkins, realizing the high-value utilization of poplar catkins.

A preparation method of an MOFs modified wood-based self-supporting conductive skeleton comprises the following steps: step (1), cutting and stamping a wood block to obtain a thin wafer; carrying out chemical delignification treatment on the thin round sheets to obtain delignified wood sheets; (2) dissolving a metal salt and a surfactant in deionized water to obtain a metal salt solution; a wood chip metal salt solution is obtained; (3) dissolving an organic ligand and an end-capping reagent in deionized water to obtain a ligand solution, adding the ligand solution into the wood chip metal salt solution, stirring and aging to obtain the MOFs modified wood chip; (4) the MOFs modified wood chips are frozen and then dried, carbonization is conducted under the protection of a reducing gas atmosphere, and the MOFs modified wood-based carbon film is obtained; and (5), a DOL / DME mixed solution containing Li2S8 is dropwise added into the MOFs modified wood-based carbon film, and the MOFs modified wood-based self-supporting conductive framework is obtained. The energy density of the lithium-sulfur battery can be improved, the cycle life is prolonged, and the electrochemical reaction kinetic performance is enhanced.

This invention relates to the field of battery fabrication, specifically disclosing a tetragonal zirconium dioxide / carbon sphere composite material and its preparation method and application. The method includes the following steps: (1) dissolving zirconium tetrachloride in a solvent, then adding dopamine, and after thorough dissolution and mixing, slowly adding ammonia water. As ammonia water is added, the solution gradually turns into a milky white opaque liquid. The solution is continuously stirred at room temperature until it gradually changes from milky white to brownish-black, obtaining a zirconium-based / polydopamine composite precursor; (2) centrifuging the obtained zirconium-based / polydopamine composite precursor, washing it to obtain a brownish-black precipitate, drying the brownish-black precipitate to obtain a brownish-black precursor powder; (3) calcining the precursor powder to obtain a tetragonal zirconium dioxide / carbon sphere composite material. This invention successfully constructs a metastable tetragonal zirconium dioxide composite catalyst induced by polydopamine and confined to the surface of carbon spheres.

The present invention belongs to the technical field of lithium-sulfur batteries, specifically a sulfur / flower-shaped Fe(OH)3 lithium-sulfur battery positive electrode material and a preparation method thereof, comprising: 1) dissolving iron salt and sodium carbonate in anhydrous ethanol and ultrapure water respectively, ultrasonically dissolving, obtaining an iron salt-anhydrous ethanol solution and a sodium carbonate aqueous solution; injecting the configured sodium carbonate aqueous solution into the iron salt-anhydrous ethanol solution with a syringe, and standing at room temperature for reaction; after the reaction is completed, a precipitate is obtained, the precipitate is centrifugally cleaned, and dried to obtain a flower-shaped Fe(OH)3; 2) grinding and mixing the obtained flower-shaped Fe(OH)3 with elemental sulfur, mixing evenly and placing in a tubular furnace for heat treatment, and obtaining a sulfur / flower-shaped Fe(OH)3 lithium-sulfur battery positive electrode material after the reaction is completed. The positive electrode material prepared by the present invention has good electrochemical properties, and the initial discharge specific capacity of the prepared electrode material at a current density of 0.1C is 1122mAh / g.

The present invention provides a method for preparing a super graphene curved carbon lithium-sulfur battery positive electrode material: (1) evenly dispersing a graphene oxide solution, freeze-drying it, and compressing it to obtain a three-dimensional graphene oxide skeleton; (2) heating chitosan and a foaming agent to obtain foamed carbon, and then ball milling to obtain a curved carbon sheet; (3) soaking the curved carbon sheet in Li 2 SO 4 solution and ultrasonically dispersed to form Li 2 SO 4 Curved carbon sheet aggregate solution; (4) immersing the graphene oxide three-dimensional skeleton into Li 2 SO 4 The curved carbon sheet aggregate rebounds in a solution and then freezes to obtain a precursor; (5) the precursor is calcined in an oxygen-free state to obtain a graphene curved carbon lithium-sulfur battery positive electrode material. The product prepared by this method can effectively enhance the specific capacity and cycle stability of lithium-sulfur batteries, wherein the curved carbon sheet can provide more space for the loading of lithium-sulfur active substances and avoid safety issues caused by battery expansion. This method is simple to prepare and is not affected by the size of the raw materials, and can meet the requirements of industrial large-scale production.

The invention provides a modified diaphragm, a preparation method and application thereof and a lithium-sulfur battery, the modified diaphragm comprises a support membrane and a composite coating on the surface of the support membrane, the composite coating contains a molecular sieve loaded with a metal oxide, a conductive carbon material and a binder, and in the molecular sieve loaded with the metal oxide, the conductive carbon material and the binder are bonded together. The amount of the metal oxide is 0.1-15 wt% of the molecular sieve. When the modified diaphragm disclosed by the invention is applied to the lithium-sulfur battery diaphragm, on one hand, migration and diffusion of polysulfide in the battery can be physically prevented by utilizing the pore structure of the molecular sieve, on the other hand, the polysulfide can be chemically adsorbed through the metal oxide, and the shuttle effect problem of the lithium-sulfur battery can be more effectively relieved by combining the two. In addition, catalytic metal is further introduced into the molecular sieve, so that the conductivity of the positive electrode side of the diaphragm can be improved by using the metal, and the conversion reaction kinetics of polysulfide can be enhanced by using the catalytic property of the metal.