174results about How to "Inhibit shuttle" patented technology

The invention provides a composite anode of a multi-layer structure for a lithium-sulfur rechargeable battery and a preparation method, which is characterized in that: an anode active substance, a conductive agent, and a binder are uniformly mixed, and then are coated on a current collector, and after coat is dried, a layer of conductive film is sprayed on the surface. The anode surface film is used for conducting and cutting off the sulfur in a cyclic process, thereby effectively raising a first capacity conservation rate of the battery and the cyclic stability.

The invention relates to the technical field of batteries, and particularly provides a preparation method of a lithium-sulphur battery positive pole material with a sulfur-graphene composite structure. The preparation method comprises the steps of mixing sulphur powder and organic amine to prepare first dispersion liquid, wherein the weight-volume ratio of sulphur and the organic amine is 0.05-0.4 g:1 mL; dispersing graphene into an organic solvent to prepare second dispersion liquid, wherein the weight-volume ratio of the graphene and the organic solvent is 0.0005-0.02 g:1 mL; dripping the first dispersion liquid to the second dispersion liquid, and uniformly mixing to form third dispersion liquid; adding water or acid liquor to the third dispersion liquid, and continuing to stir so that a sulfur-graphene composite is separated out from the third dispersion liquid; carrying out solid-liquid separation on the third dispersion liquid, and drying an obtained first solid to obtain the lithium-sulphur battery positive pole material. The lithium-sulphur battery prepared through the method provided by the invention has the advantages of good coulomb efficiency and recycling; and the preparation method provided by the invention is simple, fast and low in consumption.

The application discloses a commodity object warehouse-out information processing method and an apparatus. The method includes: pre-saving corresponding relations between storage locations and commodity object identifiers in a warehouse, storage location distribution information, and order quantity loaded by transportation carriers in each warehouse; receiving at least a warehouse-out order; determining the storage location of the commodity object associated with each order; grouping the warehouse-out orders according to the distribution information of the storage location of the commodity object associated with each order, and determining each storage location included in each group; ranking the warehouse-out orders and the storage locations included in the group in each group; and outputting a grouping result of the warehouse-out orders and order and storage location raking results in each group. According to the method and the apparatus, the warehouse-out processing efficiency can be improved.

The invention relates to a cathode material used for a lithium sulfur battery, preparation and an application thereof. The cathode material employs one or more than two carbides or nitrides of metal elements from transition metal as a catalytic component and employs elementary sulfur as an active component. The catalytic component is supported on a carrier firstly and then the active component is supported on the carrier on which the catalytic component is supported. The content of the catalytic component is 2-30% of the total weight of the cathode material and the content of the sulfur is 30-80% of total weight of the cathode material, and the balanced is the carrier. The cathode material, when being used as a cathode in the lithium sulfur battery, has excellent selectivity on reduction of elementary sulfur and reduces reaction energy barrier required for sulfur reduction, reduces reaction polarization and increases discharge voltage platform. The cathode material is environment-friendly, is low in cost and is abundant in resources.

The invention belongs to the technical field of lithium sulfur batteries, and concretely relates to a lithium sulfur battery new system. The new system comprises an electrolyte and a diaphragm matched with the electrolyte. The electrolyte is a lithium salt solution with the concentration of 0.1-3mol / L, and a lithium salt solute in the lithium salt solution is one or a mixture comprising two or more of lithium fluoride, lithium chloride, lithium bromide or lithium iodide; a solvent is one of or a mixture comprising two or more of N,N-dimethyl formamide, N,N-dimethyl acetamide, dimethyl sulfoxide, tetramethyl sulfone, tetrahydrofuran, N-methyl-2-pyrrolidone and acetonitrile; and the diaphragm is a micro-porous membrane with the aperture of 0.5-10nm or a dense membrane containing anions. The micro-porous diaphragm subjected to surface modification and hot pressing can be fully infiltrated in the micro-molecular lithium salt electrolyte and has an appropriate dimension to make electrolyte ions freely go through in order to inhibit or prevent the migration of polysulfide. The lithium salt has a low price, so the battery has the cost advantage.

The invention relates to a lithium-sulfur battery containing a barrier layer, and belongs to the field of electrochemical batteries. The surface of the positive electrode of a conventional lithium-sulfur battery is coated with a bacterial cellulose derived carbon fiber barrier layer, so that the dissolution, shuttling and battery negative electrode corrosion of polysulfide in an electrolyte solution of the lithium-sulfur battery during charging / discharging are inhibited. According to the lithium-sulfur battery containing the barrier layer, a carbon material is directly pressed on the surface of a membrane by utilizing external pressure through using an ultra-filtration cup, and the membrane is directly used after being dried without the need for stripping the carbon-containing barrier layer, so that the material waste is avoided and the effectiveness and completeness of the barrier layer are ensured. The bacterial cellulose derived carbon fiber barrier layer improves the conductive problem of sulfur as an active substance of the positive electrode of the lithium-sulfur battery, and the three-dimensional space structure of carbon fibers also provides a buffer space for volume expansion during charging / discharging, so that the electrode collapse is prevented and the electrochemical performance of the lithium-sulfur battery is improved. Under the current density of 0.5C, the initial discharge specific capacity of the battery is 1,823.2mAh / g, and the specific discharge capacity of the battery after being cycled for 100 times is 939.4mAh / g.

The invention discloses a three dimensional graphene / hollow carbon sphere / sulfur composite material, a preparation method thereof, and an application in lithium-sulfur batteries. The three dimensional graphene / hollow carbon sphere / sulfur composite material comprises nanometer elemental sulfur and a three dimensional graphene-hollow carbon sphere nano-compound, and the nanometer elemental sulfur is distributed in the three dimensional graphene-hollow carbon sphere nano-compound. The preparation method comprises the following steps: dispersing the three dimensional graphene-hollow carbon sphere nano-compound in an alcohol and water mixed solvent to obtain a suspension; and adding an aqueous solution of Na2S.9H2O and Na2SO3 into the suspension, adding an acidic solution, and reacting to obtain the three dimensional graphene / hollow carbon sphere / sulfur composite material. The composite material has the advantages of high specific capacity, stable cycle performances, and excellent rate performance and coulombic efficiency, the preparation method has the advantages of simplicity, convenience and good effect, and the composite material can be applied in the preparation of lithium-sulfur battery positive electrode materials.

The invention discloses a lithium sulfur battery anode material and a lithium sulfur battery utilizing same. By adopting an in-situ doping method, iron and nitrogen are jointly added, and an iron-nitrogen exotic atom dual-doped porous carbon material is prepared by adopting a hard template method. The method comprises the following steps: preparing a precursor, a catalyst and a previous polymer ofa hard template; calcining the previous polymer to obtain solids; and etching, cleaning and drying the solids to obtain the carbon material of the invention. The prepared carbon material is uniformlymixed with sulfur powder to be heated in an argon atmosphere to form a carbon sulfur composite material which is applied to the lithium sulfur battery. The obtained carbon material is relatively highin content of nitrogen and iron, relatively high in specific surface area and yield, simple in preparation step and easy in operation. When the lithium sulfur battery anode material is applied to thelithium sulfur battery, the electrochemical performance is relatively good, compared with the iron-free carbon material, the performance is apparently improved, the sulfur can be well fixed by addingthe iron catalyst, the shuttle of the poly-sulfide can be inhibited, and the reaction dynamics can be accelerated, so that the cycling stability of the lithium sulfur battery can be improved.

The invention discloses a multifunctional composite material based on graphene and polymer fibers and a preparation method and application of the multifunctional composite material. A three-dimensional fiber conductive network product with the polarity-rich surface and the core-shell structure is prepared by taking the non-woven fabric as a framework, thereby inhibiting the shuttle effect in the sulfur positive electrode simultaneously, and alleviating the dendritic crystal growth problem of the lithium negative electrode so as to improve the whole performance of the lithium-sulfur battery. The lithium-sulfur battery can be used in the fields of electrocatalysis, microbial fuel cells, polymer electrode membrane electrolysis and metal-air batteries due to the characteristics of high conductivity and high specific surface area so as to provide the advantages. The composite film product is obtained by reinforcing the graphene sheet with the non-woven fabric fiber yarns, has flexibility and remarkable heat conduction, electric conduction and electromagnetic shielding properties, and can ensure safe and long-acting use of related electronic equipment.

The invention relates to a carbon nitride composite material and a preparation method and an application thereof. The carbon nitride composite material comprises a substrate and a composite coating layer for covering the surface of the substrate; the composite coating layer comprises carbon nitride, a conductive agent and a binder; the conductive agent is selected from at least one kind of active carbon, acetylene black, Ketjen black, graphite, graphene and carbon nanotubes. The carbon nitride composite material can be applied to a diaphragm of a lithium-sulfur battery; when a polysulfide exists, the conductive agent can transfer electrons generated in the charge-discharge process, so that an effect of a second current collector as well as an effect of physical isolation can be played; in addition, carbon nitride has relatively high physical isolation effect and large specific surface area; and due to existence of the nitrogen element, shuttling of the polysulfide can be suppressed by the dual chemical and physical absorption effects effectively, thereby enabling the lithium-sulfur battery to be relatively high in discharge specific capacity and cycling stability.

The invention provides a metal nickel / nitrogen-doped carbon nanotube and a lithium-sulfur battery composite positive electrode material thereof. According to the material, with nickel nitrate and a nitrogen-containing organic matter adopted as raw materials, a metal nickel / nitrogen-doped carbon nanotube is prepared through a one-step high-temperature carbonization method, and is compounded with elemental sulfur through a melting-diffusion method, so that the material can be obtained; the carbon nano tube is of a bamboo joint-shaped structure; the tube diameter of the carbon nano tube is 15-75nm; a metallic nickel elementary substance is dispersed on a carbon nano tube network structure or embedded in the tube; and the particle size of the metallic nickel elementary substance is approximately consistent with the tube diameter of the carbon nano tube; and nitrogen elements are uniformly distributed on the carbon nanotube. According to the metal nickel / nitrogen-doped carbon nanotube and the lithium-sulfur battery composite positive electrode material thereof of the invention, the metal nickel / nitrogen-doped carbon nanotube is used for loading sulfur; the excellent conductivity of thenitrogen-doped carbon nanotube material, and the strong chemical interaction and electrode catalytic action of the metal nickel elementary substance on lithium polysulfide are utilized, so that the dissolution and shuttling of the lithium polysulfide can be greatly inhibited, and therefore, the lithium-sulfur battery composite positive electrode material with high specific capacity, high rate capability and high cycle stability can be obtained.

There is a cell comprising an article comprising a halogen ionomer. The article may be any element, such as a porous separator, in the cell or a modification, such as a film, a membrane, and a coating, added to an element in the cell. The halogen ionomer may be any ionomer comprising halogen, such as a fluorinated polymeric sulfonate neutralized with lithium. The halogen ionomer may also be included in a composition within an element of the cell, such as a porous separator. The cell also comprises a positive electrode including sulfur compound, a negative electrode, a circuit coupling the positive electrode with the negative electrode, an electrolyte medium and an interior wall of the cell. In addition, there are methods of making the cell and methods of using the cell.

There is a composition comprising 1 to 17.5 wt. % ionomer composition comprising halogen ionomer and 50 to 99 wt. % carbon-sulfur composite made from carbon powder having a surface area of about 50 to 4,000 square meters per gram and a pore volume of about 0.5 to 6 cubic centimeters per gram. The composite has 5 to 95 wt. % sulfur compound. There is also a layering comprising a plurality of coatings. Respective coatings in the plurality of coatings comprise respective compositions. The respective coatings comprise at least one ionomer composition comprising halogen ionomer and at least one carbon-sulfur composite of carbon powder and sulfur compound. There are also electrodes comprising the composition or layering and methods of using such in cells.

The invention discloses a thin-wall local graphitization porous carbon sphere material, a preparation method thereof and application thereof in a lithium sulfur battery. The porous carbon sphere material is a local graphitization porous carbon nanosphere with thin wall holes; the preparation method of the thin-wall local graphitization porous carbon sphere material comprises the steps that water-base resin, water-soluble inorganic salt, a surface active agent and transition metal salts are dissolved into water to obtain a spraying solution; the spraying solution is sprayed and dried to obtaina local graphitization porous carbon nanosphere precursor; the local graphitization porous carbon nanosphere precursor is subjected to pyrolysis to obtain the thin-wall local graphitization porous carbon sphere material. The preparation method is simple in technology and good in repeatability, the prepared thin-wall local graphitization porous carbon sphere material has the advantages of being good in electrical conductivity, large in aperture, high in specific surface area and the like, the thin-wall local graphitization porous carbon sphere material is applied to a lithium sulfur battery sulfur carrier, the high specific capacity, long cycling stability and high rate capability are achieved, and the wide application prospect is achieved.

The embodiment of the invention discloses a warehouse operation control method, device and system. A warehouse comprises a goods picking area and a packaging area, and the goods picking area comprisesa plurality of goods shelves for storing goods; the system comprises a first server and a plurality of transport vehicles, wherein the first server is used for generating a plurality of order pickingtasks according to orders of the same batch in a warehouse, and distributing the plurality of order picking tasks to the plurality of transport vehicles; the transport vehicles are used for obtaininga first driving path used for completing the order picking task and a second driving path used for conveying an order picking result to a target position, driving to a target goods shelf according tothe first driving path, and conveying the target goods according to the second driving path after the target goods are loaded. Through the embodiment of the invention, the operation efficiency in thewarehouse can be improved, and meanwhile, the software and hardware costs are controlled.

The invention discloses a preparation method of a lithium-sulfur battery sandwich layer material. The preparation method comprises the following steps of (1) enabling sodium molybdate dihydrate and thiourea to be added to deionized water to prepare into a mixed solution A; in addition, enabling copper chloride dihydrate (and thiourea) to be added to deionized water to obtain a solution B; and (2)enabling the A solution to be mixed with the B solution to obtain a solution C, enabling the solution C to be added to a GO solution to be mixed to obtain a mixed solution D; and transferring the mixed solution D to a reaction kettle which takes polytetrafluoroethylene as a substrate, putting the reaction kettle into a drying oven, and performing heat preservation at a temperature of 180-220 DEG Cfor 2-30h to obtain the lithium-sulfur battery sandwich layer material. By adoption of the preparation method, the shortcomings of obvious "shuttle effect" of polysulfide in the lithium-sulfur battery prepared in the prior art, high volume expansion effect of the lithium-sulfur battery, instable electrochemical performance of the battery and the like are overcome, and the production process is simplified.

The invention discloses a positive electrode material for a lithium-sulfur battery. The positive electrode material comprises a carrier and active ingredients, wherein the carrier is a conductive carbon material, and a non-conductive halogen compound is loaded on the surface of the conductive carbon material. The invention also discloses a preparation method for the positive electrode material; the preparation method comprises the steps of mixing the halogen compound with a solvent A until the mixture is thick; blowing the mixture to the surface of the conductive carbon surface at a temperature of 100-200 DEG C under an inert gas to load the halogen compound on the surface of the conductive carbon material, and recording the product as the substrate; and enabling the active ingredients to be mixed with a solvent B to obtain a solution, adding the solution to the substrate in a dropwise manner, and drying to obtain the positive electrode material for the lithium-sulfur battery. The invention provides the positive electrode material for the lithium-sulfur battery; the conductive carbon material is compounded with the non-conductive halogen compound to be used as the carrier of the active ingredients, so that the dissolution of the lithium sulfide and the shuttle flying among the lithium-sulfur electrodes can be effectively restrained; and the capacity of the lithium-sulfur battery and the cycling times can be greatly increased.

The invention discloses a multifunctional lithium-sulfur battery diaphragm which is characterized by comprising a basic diaphragm and a coating layer, wherein the coating layer comprises graphene oxide and a main body material, and the main body material is one of boron nitride, aluminum carbonitride or molybdenum disulfide. The invention further discloses a preparation method and application of the multifunctional lithium-sulfur battery diaphragm. According to the multifunctional lithium-sulfur battery diaphragm disclosed by the invention, the graphene oxide is adopted to induce the main bodymaterial, so that the dispersity problem of the nano materials is solved, the two nano materials are compounded in order, shuttling of polysulfide is more effectively inhibited, and the mechanical strength and heat resistance of the diaphragm are synergistically enhanced. According to the preparation method of the diaphragm, a solvent evaporation induced self-assembly means is adopted, so that ordered compounding of two 2D nano materials is realized, the coating thickness can be flexibly controlled, and large-scale production is realized.

The invention provides a boron / nitrogen double-doped porous carbon nanosheet and a lithium-sulfur battery positive electrode material thereof. According to the technical scheme, urea, boric acid and polyethylene glycol serve as raw materials, the boron / nitrogen double-doped porous carbon nanosheet is prepared through high-temperature carbonization, and the prepared boron / nitrogen double-doped porous carbon nanosheet is of a graphene-like two-dimensional sheet structure and has a high specific surface area and rich micropores and mesopores; on the basis, the boron / nitrogen double-doped porous carbon nanosheet is used as a carrier, and the positive electrode materials with different sulfur contents are prepared by a melt diffusion method. In the lithium-sulfur battery positive electrode material provided in the invention, the unique two-dimensional structure of the boron / nitrogen double-doped porous carbon nanosheet is beneficial to promoting rapid transfer of electrons and relieving volume expansion of a sulfur electrode, and boron / nitrogen doped atoms have a relatively strong Lewis acid-base effect on lithium polysulfide, so that the shuttle effect of the electrode can be effectively inhibited, and relatively high specific capacity and excellent cycle performance are shown.

The invention belongs to the technical field of new energy materials and devices, and particularly relates to a composite modified diaphragm for a lithium-sulfur battery and a preparation method of the composite modified diaphragm. The CNTs layers and the CeO2-x / C / rGO layers are alternately laid on the surface of one side of the commercial battery diaphragm matrix, and the CNTs layers are in contact with the diaphragm matrix. The preparation method comprises the following steps: preparing a cerium-based metal organic framework Ce-MOF and GO compound by taking trimesic acid, graphene oxide andcerous nitrate as raw materials; calcining to obtain a CeO2-x / C / rGO composite material rich in oxygen vacancies, and then alternately carrying out suction filtration on the activated CNTs and the CeO2-x / C / rGO material on the surface of one side of the commercial battery diaphragm matrix layer by layer to obtain the composite modified diaphragm for the lithium-sulfur battery. The modified diaphragmcan effectively inhibit the shuttle effect of the lithium-sulfur battery, greatly improves the capacity and rate capability of the battery, prolongs the cycle life of the battery, and is simple in manufacturing method, low in cost and suitable for large-scale production.

The invention belongs to the technical field of the lithium-sulfur battery, and relates to a method for preparing a functionality interlayer through an active material, specifically a preparation method of the composite material for a lithium-sulfur battery and an application of taking the composite material as the lithium-sulfur battery functionality interlayer. The iron phosphate / carbon-cloth composite material (FeP / CC composite material) is prepared by utilizing a tubular furnace heating process; the prepared FeP / CC composite material is used as the functionality interlayer for a lithium-sulfur battery, the transmission rates of the electron and the ion are accelerated, the redox reaction of the lithium-sulfur battery in the charging / discharging process is promoted, the polysulfide is well adsorbed, and the shuttle effect of the polysulfide is restrained.

The invention belongs to the field of electrolytes, and particularly relates to a functionalized diaphragm for a lithium-sulfur battery as well as preparation and application of the functionalized diaphragm. The functionalized diaphragm is an organic-inorganic structure ordered electrolyte material obtained by layer-by-layer self-assembly of a material with positive and negative charges through electrostatic interaction force; wherein the positively charged material is composed of a hydrophilic positively charged polymer coated inorganic nano material with high mechanical strength and high stability, and the negatively charged material is a hydrophilic negatively charged polymer which can be stably dispersed in water. By simply, conveniently and accurately regulating and controlling the composition, the thickness and the structure of the layer-by-layer self-assembly material, shuttling of polysulfide and growth of lithium dendrites in the charging and discharging process of the lithium-sulfur battery can be effectively inhibited, so that the cycling stability and the safety of the lithium-sulfur battery are improved.

The invention provides a lithium-sulfur battery. The lithium-sulfur battery comprises a sulfur-based positive electrode, a lithium-based negative electrode, a separator and a functional material layer, wherein the separator is arranged between the sulfur-based positive electrode and the lithium-based negative electrode, the functional material layer is arranged between the sulfur-based positive electrode and the lithium-based negative electrode, the material of the functional material layer comprises a Li-H-M-O system compound containing elements of Li, H, M and O, and M is a transition metalelement. The invention also provides a composite separator, a lithium-sulfur battery electrode assembly, a composite sulfur-based positive electrode, a composite lithium-based negative electrode and application of the functional material layer in the lithium-sulfur battery.

The invention discloses a preparation method for a flexible positive pole of a lithium selenium battery. The preparation method comprises the steps that one side of a membrane is coated with a multi-walled carbon nanotube polyselenide adsorption layer; then a hollow carbon fiber and element-selenium compound material is subjected to vacuum filtration, and a membrane of a multi-walled carbon nanotube is coated with the hollow carbon fiber and element-selenium compound material, so that an active material layer is formed, and the flexible positive pole of the lithium selenium battery is obtained. The preparation method is simple in operation and low in cost, the flexible positive pole of the lithium selenium battery obtained through the method has good mechanical property and electrical property, and is high in selenium loading capacity and active material utilization rate, the cycling stability and the rate capacity of the lithium selenium battery are greatly improved, and the preparation method has high application potential and commercial value.

A carbon-coated molybdenum sulfide / water hyacinth biomass carbon composite material and a preparation method and use thereof comprise the following steps of: Including: the first step, using sodium molybdate and thioacetamide as raw materials, through a 160-200 DEGC hydrothermal method, growing a MoS2 nanosheet array on the surface of the bulbous water hyacinth biomass carbon; the second step, 80-100 DEG C water bath method is coated on the MoS2 nanosheet array with a layer of dopamine polymer; the third step is to carbonize the polymerized dopamine to form a carbon coating layer by calcination at 500 to 800 DEG C in an inert atmosphere to obtain carbon coated molybdenum sulfide. / Water hyacinth biomass carbon core shell composite. The invention has simple operation, large output and uniform coating layer . The invention has the advantages of simple operation, large output and uniform coating layer. The composite material has the advantages of low cost, high reversible charge-dischargecapacity, long cycle life and excellent rate performance when it is used as a sodium ion negative electrode material.

The invention discloses a sulfur-doped three-dimensional porous graphene / sulfur composite positive electrode material and a preparation method and an application thereof. The sulfur-doped three-dimensional porous graphene / sulfur composite positive electrode material is composed of elemental sulfur deposited on a surface of a three-dimensional carbon skeleton of sulfur-doped three-dimensional porous graphene in situ; and the preparation method comprises the steps of first adding sodium bisulfate to a graphene oxide dispersion to react, then adding sodium sulfide to react under a partially neutral condition, carrying out liquid-solid separation, and performing freeze-drying on a solid product, thereby obtaining the sulfur-doped three-dimensional porous graphene / sulfur composite positive electrode material. A sulfur-doped amount of the composite positive electrode material is large, a sulfur loading capacity is controllable, a load is uniform and a utilization rate of an active substance sulfur is high; the sulfur-doped three-dimensional porous graphene / sulfur composite positive electrode material has the advantages of high specific capacity, high energy density, high stability and the like; and the cycle performance of a lithium-sulfur battery is greatly improved.

The invention discloses a lithium-sulfur diaphragm with a synergistic effect mechanism, a preparation method of the lithium-sulfur diaphragm and a lithium-sulfur battery, and belongs to the technicalfield of battery diaphragms. According to the invention, the porous conductive carbon material is added into the positive electrode side functional layer; a nano oxide material is added into the negative electrode side functional layer; the positive side and the negative side on the two sides of the diaphragm base membrane are coated with the functional layer slurry to prepare the lithium-sulfur diaphragm with a synergistic effect mechanism. The prepared lithium-sulfur diaphragm is applied to the lithium-sulfur battery, so that the shuttle effect caused by lithium polysulfide in the cycle process of the lithium-sulfur battery can be effectively inhibited, the deposition of lithium sulfide on the surface of an electrode can be reduced, lithium dendrites are prevented from piercing a pole piece, and the capacity retention ratio and the cycle effect of the lithium-sulfur battery are improved.

The invention relates to titanium dioxide doped carbon nitride, and a preparation method and application thereof. The preparation method of the titanium dioxide doped carbon nitride comprises the following steps: adding carbon nitride into alkaline liquid and performing ultrasonic treatment until the carbon nitride is dispersed uniformly to obtain first dispersing liquid; adding titanium dioxide into the first dispersing liquid and performing ultrasonic treatment until the titanium dioxide is dispersed uniformly to obtain second dispersing liquid; and performing hydrothermal treatment on the second dispersing liquid to obtain the titanium dioxide doped carbon nitride. The titanium dioxide doped carbon nitride prepared by the preparation method of the titanium dioxide doped carbon nitride is applied to a lithium sulfur battery diaphragm, the carbon nitride and the titanium dioxide can exert a good synergistic effect and have strong adsorption effect on sulfur, the shuttle effect of polysulfide is inhibited, and redox reaction of the sulfur is benefited, so that the specific capacity and the cycling stability of the battery are improved.

The invention discloses a multifunctional diaphragm of a lithium-sulfur battery, which comprises a diaphragm substrate, wherein at least one surface of the diaphragm substrate is coated with a modified coating, the modified coating is a composite coating containing polydopamine, a carbon material and a catalytic material, and a catalyst is one or more of metal sulfide, metal carbide and metal oxide. The preparation method comprises the steps of firstly preparing a polydopamine / carbon dispersion liquid, then uniformly mixing the polydopamine / carbon dispersion liquid with the catalytic material, the thickening agent and other assistants to prepare slurry, finally coating the surface of the diaphragm matrix with the slurry, and drying to obtain the multifunctional diaphragm of the lithium-sulfur battery. The lithium-sulfur battery diaphragm prepared by the invention has shuttling inhibition and catalytic conversion functions on polysulfide, oxygen-containing functional groups in a polydopamine molecular chain inhibit shuttling of the polysulfide, the polysulfide is adsorbed on the coating side of the diaphragm under the action of the catalytic material and the carbon material, and polysulfide is prevented from shuttling to the negative electrode through the inhibition-conversion effect, so that the cycle life of the lithium-sulfur battery is remarkably prolonged.

The invention provides a functionalized diaphragm for a lithium-sulfur battery, which comprises a base membrane, and a conductive adsorption coating is arranged above the base membrane; the conductiveadsorption coating comprises a conductive powder carbon material and an adsorption inorganic polar material; the adsorption inorganic polar material is obtained by carrying out heat treatment on a precursor. The functionalized diaphragm for the lithium-sulfur battery is composed of an inorganic polar material prepared by spray drying and a conductive carbon material, so a barrier layer for inhibiting shuttling of polysulfide in positive and negative electrodes can be established, conversion of polysulfide is catalyzed, the utilization rate of sulfur in a lithium-sulfur battery system is effectively increased, the specific capacity, the cycling stability and the thermal stability of the lithium-sulfur battery are improved, and the functionalized diaphragm has good electrochemical performance; the functional layer has double effects, namely, a strong polar substance adsorbs and anchors shuttled polysulfide, and can catalyze the conversion of the polysulfide.