48results about How to "High specific energy density" patented technology

The invention discloses a method for preparing a porous carbon material for an electrochemical capacitor from egg white used as a raw material, and belongs to the technical field of novel energy sources. The preparation method comprises the following steps: firstly adding neutral salts or an organic solvent into egg white used as the raw material to separate out protein, and carrying out high-temperature pre-carbonization on the protein so as to obtain a carbon precursor; then obtaining the high-performance porous carbon material for the supercapacitor by use of an alkali metal hydroxide activation method, wherein egg white is taken as a raw material. The method disclosed by the invention is capable of using biological materials and has the advantages of novel raw materials, low cost and wide sources, the porous carbon material prepared has the advantages of rich microporous / mesoporous multi-level pore structures, high specific surface area and excellent electrochemical capacitance performance and has broad application prospects in the field of electrochemical capacitors.

The invention provides a method of making fluorine-containing gel state electrolyte material and polymeric lithium ion cells by employing in-situ thermal cross bonding process, wherein fluorine-containing acrylic ester material is used as monomer, and double functional group acrylic acid ester containing polyethylene glycol or triple functional group acrylic acid ester containing polyethylene glycol are used as cross linking agent, the making process comprises injecting the miscible liquid comprising monomer, cross linking agent, thermal initiation agent and lithium ion electrolyte salt solution into the core of lithium ion cells, heating the cell to result in-situ thermal chemical cross-linking for the two acrylic esters, whereby the acrylic ester copolymer network bundles the solution in the electrolyte, forming the gel state electrolyte material with stabilized physical and chemical properties.

The invention relates to a method for preparing different-electrode composite materials of a carbon plate / manganese dioxide nanometer sheet and the application thereof. In the application, the prepared composite materials serve as the anode materials, the carbon plate serves as the cathode materials, and the anode materials and the cathode materials are together assembled into an asymmetric capacitor. The method includes: using a mesoporous carbon nanometer sheet to serve as a carrier to react with potassium permanganate (KMnO4) after acidification to obtain the different-electrode composite materials of the carbon plate / manganese dioxide nanometer sheet. The acidified carbon plate and the KMnO4 have a redox reaction, and the carbon plate can increase the conductivity of the manganese dioxide nanometer sheet, and simultaneously improve the electrochemical stability and multiplying power characteristics of the composite materials. The content of the manganese dioxide in the composite materials can be controlled by adjusting the time of the redox reaction, and accordingly the electrochemical performance of the composite materials can be affected. The method is simple, the raw materials are low in cost, the content of the components in the composite materials can be adjusted easily, scale production can be carried out easily, and the assembled asymmetric capacitor has the advantages of being high in specific capacitance, high in energy density and good in stability.

The invention discloses a cobalt-nitrogen co-doped carbon-based electrocatalyst material and a preparation method thereof, and belongs to the field of electrochemistry and new energy, wherein the cobalt-nitrogen co-doped carbon-based nano material is prepared by taking an anionic metal organic framework encapsulated with metal cobalt ions as a precursor through a high-temperature pyrolysis methodin a nitrogen atmosphere, and has excellent oxygen reduction, oxygen evolution and hydrogen evolution catalytic performances under an alkaline condition. According to the invention, a rechargeable zinc-air battery and a full water splitting device assembled by utilizing the material have good charging and discharging performance and long-term stability; and the preparation process is simple, and the catalyst is good in performance, economical and capable of being prepared on a large scale.

The invention discloses a composite lithium battery and a preparation method thereof. The composite lithium battery comprises an anode, a cathode, electrolyte and a diaphragm, wherein the anode comprises an anode active substance; the anode active substance is prepared from elemental sulfur and ferric phosphate or sulfide and lithium iron phosphate in a compounded manner; and the cathode is a lithium metal cathode or a composite cathode of metallic lithium and carbon. As the advantages of high specific volume of sulfur and high security and long service life of a lithium iron phosphate material are utilized, the defect that a conventional lithium iron phosphate ion battery is low in discharge energy density can be avoided, the defects that a lithium sulfur battery is low in security and poor in circulation property can be also avoided, and comprehensive properties of energy density, security and circulation service life of the battery can be improved.

The invention relates to a graphene / manganese dioxide-based asymmetric coaxial fiber supercapacitor and preparation and application thereof. The capacitor has a three-layer structure. The inner electrode in the center is graphene / manganese dioxide hybrid fiber, and the outer layer is pure graphene. The two layers are separated by phosphoric acid / polyvinyl alcohol as electrolyte. The preparation methods includes preparation of graphite oxide dispersion, preparation of manganese dioxide nanorods, preparation of graphite oxide / manganese dioxide hybrid fibers, and preparation of graphene / manganesedioxide-based asymmetric coaxial fiber supercapacitors. The supercapacitor has high bulk energy density and good flexibility. The preparation process is simple and the cost is low, the graphene / manganese dioxide-based asymmetric coaxial fiber supercapacitor is expected to be used in the fields of flexible energy storage and wearable devices.

The invention discloses a method of fabricating a 3D bulk silicon microcapacitor, which comprises steps of fabricating of a 3D bulk silicon substrate structure, introduction of an active material forthe 3D structure and three kinds of packaging and integration of the capacitor. Firstly, deep silicon etching is carried out to obtain a hollow 3D silicon-based comb substrate; the upper surface, thelower surface and the side wall of the comb are then coated with a carbon-based conductive layer and the active material; and finally, a gel-like electrolyte is applied to the surface, packaging and integration are carried out, and the 3D bulk silicon microcapacitor is obtained. In comparison with the conventional comb planar structure, the longitudinal height of the microcapacitor electrode is extended, the available electrode surface area is expanded from a two-dimensional plane to a three-dimensional surface and longitudinal side wall, the 3D electrode can carry more active material, the specific capacitance and the specific energy density are thus enhanced, the 3D comb structure active material introduction method is of great significance for the research of 3D capacitors, and the proposed packaging and integration method ensures the stability and the service life of the capacitor.

The invention provides a preparation method of high-performance lithium salt, and belongs to the technical field of lithium salt for a battery. The preparation method comprises the following steps ofA, using vinyl sulfonyl fluoride or 1,3-propane bi-sulfonyl fluoride as the raw material, leading ammonia gas to bubble, adding diethyl ether, and acting at the temperature of 5 to 10 DEG C, so as toobtain sulfonyl amide or 1,3-propane bisulfonyl amide; B, adding the product obtained in step A into lithium hydroxide, and reacting at the temperature of 50 to 60 DEG C, so as to obtain the high-performance lithium salt, wherein the high-performance lithium salt contains the high-performance lithium salt and the high-performance lithium salt with substituted perfluoroalkyl. The preparation methodhas the advantages that the preparation method is simple; a wholly novel preparation method for the lithium salt of the battery is provided; the yield rate of the product is high, the purity is high,and the property is good after the high-performance lithium salt is applied to the battery.

The invention relates to a conductive carbon black modified silicon dioxide aerogel loaded sulfur composite positive electrode material and a preparation method thereof. The composite positive electrode material comprises conductive carbon black modified silicon dioxide aerogel and elementary sulfur loaded to the conductive carbon black modified silicon dioxide aerogel; and the conductive carbon black modified silicon dioxide aerogel comprises silicon dioxide aerogel and conductive carbon black doped in the silicon dioxide aerogel. The preparation method comprises the steps of enabling the conductive carbon black modified silicon dioxide aerogel and the elementary sulfur to be mixed uniformly to obtain a mixture; and performing heat treatment on the obtained mixture at a temperature of 115-160 DEG C in a sealed condition under inert gas protection to obtain the conductive carbon black modified silicon dioxide aerogel loaded sulfur composite positive electrode material. The composite positive electrode material prepared in the invention has many advantages of excellent capacity performance and cycle stability, high coulombic efficiency and the like in a lithium-sulfur battery. The composite positive electrode material is simple and convenient in method and low in cost, and batch production can be realized easily.

An electrochemical hybrid capacitor which is based on a water-based acidic electrolyte belongs to the technical field of chemical power supplies. A positive electrode in the electrochemical hybrid capacitor adopts electrode materials and carbon materials which are applicable to water-based inorganic acid solution; a negative electrode adopts one or the mixture of more than two of activated carbon with porous structure, mesoporous carbon, carbon fiber and carbon aerogel; the electrochemical hybrid capacitor is characterized in that the support electrolyte is water-based acidic solution containing metal salts, wherein, the metal salts comprise one or the mixture of more than two of the metal salts which are easily dissolved in H2SO4, H3PO4, HCL or HNO3 solution and contain inorganic metal irons with the valence states of +1, +2 and +3. Compared with the general non-symmetric hybrid capacitor, the supercapacitor has higher energy density due to the addition of the metal salts; furthermore, as the sources of the materials are wide, the cost is low and the preparation is easy, the electrochemical hybrid capacitor has great application prospect.

The invention provides a manganese dioxide@sulfur@carbon sphere positive electrode composite material with a yolk-shell structure as well as a preparation method and application thereof. According tothe manganese dioxide@sulfur@carbon sphere composite material, manganese dioxide of a flaky structure serves as a core and is distributed in a cavity with a carbon sphere serving as a shell, sulfur isdistributed between the manganese dioxide core and the carbon shell, and the composite material comprises 10%-30% of carbon, 10%-30% of manganese dioxide and 40%-80% of sulfur. The hollow carbon spheres provide sufficient sulfur loading space; moreover, the rich point-to-point contact among the carbon spheres ensures the rapid transmission of electrons, the flaky manganese dioxide core layer in the carbon sphere cavity has a strong chemical adsorption conversion effect on polysulfide, the shuttle effect can be effectively inhibited by combining the physical limitation effect of the carbon layer, and the capacity retention ratio, the cycling stability and the rate capability of the battery are improved.

The invention discloses a current collector. The current collector is made of a fiber reinforced carbon aerogel composite material; the fiber-reinforced carbon aerogel composite material is a high-conductivity porous carbon material and comprises carbon aerogel and fibers, and the fibers are filled in the carbon aerogel. The invention also relates to a preparation method of the current collector, an electrode plate, a preparation method of the electrode plate and a lead-acid battery.

The invention discloses a preparation method of a negative electrode lithium-supplementing high-nickel lithium ion power cell; according to the method disclosed by the invention, a positive electrodehigh-nickel material can be made to play the optimal performance by adjusting the proportion; the preparation method of the negative electrode lithium-supplementing lithium ion power cell comprises the following steps of coating a negative electrode slurry on a negative electrode current collector to obtain a negative plate, and then, carrying out rolling on the negative plate, wherein during rolling, two metal lithium sheets are placed on the two sides of the negative plate for rolling respectively. According to the preparation method, when the coated negative plate is rolled, and the metal lithium sheets are pressed on the two surfaces of the negative plate, so that the initial coulombic efficiency of the single lithium ion cell and the specific energy density of the cell are improved. The specific energy of the single lithium ion power battery is 300 Wh / kg or above.

The invention discloses a polyaniline nanowire / graded porous carbon composite material as well as a preparation method and application thereof. The method is characterized in that a hollow mesoporous silicon / carbon compound serves as a carrier; a polyaniline nanowire array grows on the surface of the carrier with a chemically oxidative copolymerization method; and then, a hollow mesoporous silicon template is removed by hydrofluoric acid to obtain the polyaniline nanowire / graded porous carbon composite material. The composite material prepared by the method can better keep the mesoporous duct of graded porous carbon, and the specific surface area and the hole volume of the composite material are improved so as to enhance the electrochemical stability and the multiplying power characteristics of the composite material. The concentration of aniline in reactant is regulated to control the content and the morphological structure of the polyaniline in the composite material so as to affect the electrochemical performance of the composite material. The preparation method has the active effects of simple preparation process and low cost, the content of each component in the composite material is easy to regulate, and large-scale production is easy to carry out. The prepared electrode material has the advantages of high specific capacity, favorable circulating stability and multiplying power characteristics.

The flow field distributing board for proton exchange fuel cell is produced with metal sheet and through punching. The metal sheet may be of stainless steel, titanium, silver, niobium, their alloy or other excellent conductor; and on the surface of the metal sheet one layer of gold or other coating may be plated. The metal sheet is first perforated through punching, laser processing, high-energy ray treatment or other method to form circular, triangular or polygonal holes; and then punched to form platforms flat lugs around hole. The lugs has direction perpendicular to that of the adjacent ones, cross positions and squared, S-shaped, trapezoid, polygonal or combined shape.

The invention relates to a preparation method of a high-compaction lithium iron phosphate pole piece, a lithium iron phosphate material is composed of large particles and small particles with different sizes, and the preparation method comprises the following steps: nanocrystallization of an initial raw material, pretreatment of the initial material, high-temperature sintering, and mixing and size mixing of a lithium iron phosphate active material, a conductive agent and a binder according to a ratio; and coating an aluminum foil with the slurry according to a fixed thickness to obtain a high-compaction positive pole piece. The method is simple in step operation, easy in condition control and convenient for large-scale production, and the energy density of the battery is greatly improved.

The invention relates to a preparation method of a modified lithium ion battery electrode, The cathode and anode of an additive are prepared by using a graphite rod as an arc method, The cathode and anode of the two graphite rods are oppositely placed in a reaction medium of liquid nitrogen, liquid argon or water, and the high-voltage current is fed into the reaction medium for DC arc discharge toobtain the additive carbon nanohorn or carbon onion, and then the 300V-500V voltage is applied under the atmosphere of either nitrogen or ammonia gas or a mixture of the two gases for reacting for aperiod of time to obtain the modified additive, and the modified additive is added into the electrode slurry composed of active material, a solvent, a binder and a conductive agent to obtain the modified lithium ion battery electrode by high-speed stirring under vacuum ring. The invention has the advantages of effectively enhancing the electric conductivity and the thermal conductivity of the electrode, effectively improving the lithium ion adsorption performance of the negative electrode, effectively extracting the specific energy density and the specific power density of the electrode, and prolonging the circulating service life of the electrode.

The invention discloses a preparation method of a conjugated carboxylate negative electrode material of a lithium ion battery. The method comprises the steps of enabling [2, 2': 6', 2''- terpyridine]-4, 4', 4''-tricarboxylic acid and alkali to be subjected to a neutralization reaction to synthesize [2, 2': 6', 2''- terpyridine]-4, 4', 4''-lithium tricarboxylate; reacting with nitrates corresponding to fourth periodic element metals cobalt, nickel, copper and zinc at a temperature of 60 DEG C for 5 hours to synthesize [2, 2': 6', 2''- terpyridine]-4, 4', 4''-tricarboxylate; and grinding the synthetic material, acetylene black, and polyvinylidene fluoride in N-methyl pyrrolidone, coating the mixture on a copper foil, drying the coated copper foil, cutting the dried copper foil into pieces, manufacturing button cells in a glove box, and carrying out electrochemical performance characterization. The conjugated carboxylate synthesized according to the method provided by the invention contains multiple discharge sites such as a valence-variable metal center and carboxylate radicals; the conjugated carboxylate synthesized according to the method can make good use of a synergistic lithiumstorage effect among the carboxylate, a conjugated aromatic system and variable-valence metal, and the electrochemical performance of the material is improved. It is found that the material has relatively high specific discharge capacity and excellent cycle performance through a constant current charge-discharge test.

The invention belongs to the field of supercapacitors, and particularly relates to an asymmetric supercapacitor monomer and a preparation method thereof. The supercapacitor comprises a positive electrode, a negative electrode and a membrane infiltrated by an electrolyte, wherein the positive electrode is a current collector to which a porous polypyrrole-carbon nanotube composite (PPy-CNT) is attached; the negative electrode is the current collector to which carbon black is attached; and the mass ratio of the porous polypyrrole-carbon nanotube composite to the carbon black is 1.1-2.3. The adopted positive capacitance and negative capacitance are not equal, so that, compared with the prior art, the asymmetric supercapacitor has the advantages that the amount of a positive electrode material is significantly increased and the amount of a negative electrode material is reduced; the advantages of a PPy-CNT porous three-dimensional structure of the positive electrode can be better developed; the disadvantage that a negative electrode carbon material is relatively poor in ion diffusion ability is weakened; the voltage of the supercapacitor is increased by over 1.5 times; and the corresponding specific energy and power density are more than doubled.

The invention relates to a folding graphene current collector and a preparation method thereof, and a lithium ion battery. The folding graphene current collector improves the resistance of a pole piece, reduces the internal resistance of the battery, increases the contact area ratio of the current collector to an active substance, increases the specific energy density of the battery and reduces the cost of the battery. According to the invention, the folding graphene current collector is novel current collector integrating an interlaced current collector with a conventional coating current collector; a first layer of an active substance on coats a light foil current collector, then interlaced current collector is folded and embedded into the active substance, and then coating of another layer of the active substance is conducted; and meanwhile, conducting modification treatment is conducted on the surface of the interlaced current collector; the contact area and binding force of the active substance and the current collector are increased and the resistance of the pole piece is improved from the above two aspects, so the internal resistance of the battery is greatly reduced; and meanwhile, the usage amounts of foil, a conductive agent and a binder are reduced, the specific energy density of the battery is improved, and battery cost is reduced.

The invention relates to a folded graphene current collector, a preparation method and a lithium-ion battery that improve the electrode sheet resistance, reduce the internal resistance of the battery, increase the contact area ratio between the current collector and the active material, increase the specific energy density of the battery, and reduce the cost of the battery. A new type of current collector that combines a braided current collector with an existing coated current collector, coating the first layer of active material on the light foil current collector, then folding the braided current collector into the active material, and then coating a layer Active material; at the same time, conduct conductive modification on the surface of the braided current collector; from these two aspects, the contact area and bonding force between the active material and the current collector are improved, and the resistance of the electrode sheet is improved, thereby greatly reducing the internal resistance of the battery; The amount of conductive agent and binder used can increase the specific energy density of the battery and reduce the cost of the battery.

The invention relates to a preparation method of a primary large-particle lithium nickel cobalt aluminate anode material. The method is characterized by preparing a spherical nickel cobalt aluminium precursor by using a liquid phase method, then carrying out roasting by using a three-stage method, adding a certain amount of specific flux during second roasting, carrying out high-temperature roasting after uniformly mixing the materials, then washing away the flux and carrying out third roasting, thus obtaining the product after roasting, namely primary large-particle lithium nickel cobalt aluminate. The primary large-particle lithium nickel cobalt aluminate material has higher tap density and compaction density, the cycle life of the material is greatly prolonged under the conditions of high-temperature cycle and high voltage, and ballooning is obviously weakened after the material is used for preparing soft-package batteries. The process is simple and practicable and can be used for large-scale industrial production.

The invention provides a manganese dioxide@sulfur@carbon sphere positive electrode composite material with a yolk-shell structure as well as a preparation method and application thereof. According tothe manganese dioxide@sulfur@carbon sphere composite material, manganese dioxide of a flaky structure serves as a core and is distributed in a cavity with a carbon sphere serving as a shell, sulfur isdistributed between the manganese dioxide core and the carbon shell, and the composite material comprises 10%-30% of carbon, 10%-30% of manganese dioxide and 40%-80% of sulfur. The hollow carbon spheres provide sufficient sulfur loading space; moreover, the rich point-to-point contact among the carbon spheres ensures the rapid transmission of electrons, the flaky manganese dioxide core layer in the carbon sphere cavity has a strong chemical adsorption conversion effect on polysulfide, the shuttle effect can be effectively inhibited by combining the physical limitation effect of the carbon layer, and the capacity retention ratio, the cycling stability and the rate capability of the battery are improved.

The invention discloses a negative electrode material of a water-system lithium ion battery LiyTi2-xMx(PO4)3 / C (wherein 0<= x <=0.4, and 0.8<= y <=1.2) and a preparation method thereof. The preparation method comprises the following steps: slowly adding a solution containing a phosphorus source into a metal ion-doped solution containing a titanium source, a lithium source and a carbon source and carrying out reflux heating; then drying a solvent through steaming; and carrying out sintering in a reducing atmosphere so as to obtain the target material. The prepared target material has a nanometer particle size and a high specific surface area, is uniformly coated by carbon and shows excellent cycle stability when used as a negative electrode of the water-system lithium ion battery. The preparation method has the advantages of short process flow, simple operation and easy realization of industrial production.

The invention relates to a Co3O4 / Co2P coaxial heterostructure material and a preparation method thereof. The preparation method includes the following steps: (1) sintering cobalt hydroxide nanowires in a hydrogen phosphide atmosphere to obtain cobalt phosphide nanowires; and (2) quickly annealing the cobalt phosphide nanowires to oxidize the surface layer to obtain a micro super capacitor electrode material with a Co3O4 / Co2P coaxial heterostructure. The beneficial effects are as follows: for the Co3O4 / Co2P coaxial heterostructure, the outer Co3O4 will provide pseudocapacitance capacity, whilethe inner Co2P has high conductivity; and meanwhile, because the electrochemical reaction only occurs on the surface or near the surface of the material, the inner Co2P cannot directly contact and adsorb solution ions at high reaction potential, and water decomposition will not be catalyzed. Therefore, the coaxial heterostructure maintains high capacity and cyclic stability, and has good electronic conductivity and higher rate performance.

The invention relates to a supercapacitor electrode material of a laminated perovskite type nanometer oxide. The material has an iron / manganese / cobalt / nickelate doped oxide nanometer material of a 214type laminated perovskite structure with a chemical formula of L2-xXxMO4-delta, the iron / manganese / cobalt / nickelate doped oxide nanometer material of the laminated perovskite structure carrying Ag, and the iron / manganese / cobalt / nickelate doped oxide nanometer material of the laminated perovskite structure in which graphene is combined. In the chemical formula, L is one or mixture of trivalent rare earth metal ions including La, Pr, Nd and Sm, X is the one or mixture of divalent metal ions of Mg, Ca, Sr, Ba and Pb, M is one or mixture of Fe, Mn, Co and Ni, and x is not less than 0 and not morethan 2, and delta is not more than 1 and not less than -1. The iron / manganese / cobalt / nickelate doped perovskite structure oxide of the laminated perovskite structure comprises nanometer powder with grain size of 10-100nm, film with thickness of 50-1000nm, and nanometer fibers with diameters of 100-500nm and lengths of 500-5000nm.

The invention discloses a method of fabricating a 3D bulk silicon microcapacitor, which comprises steps of fabricating of a 3D bulk silicon substrate structure, introduction of an active material forthe 3D structure and three kinds of packaging and integration of the capacitor. Firstly, deep silicon etching is carried out to obtain a hollow 3D silicon-based comb substrate; the upper surface, thelower surface and the side wall of the comb are then coated with a carbon-based conductive layer and the active material; and finally, a gel-like electrolyte is applied to the surface, packaging and integration are carried out, and the 3D bulk silicon microcapacitor is obtained. In comparison with the conventional comb planar structure, the longitudinal height of the microcapacitor electrode is extended, the available electrode surface area is expanded from a two-dimensional plane to a three-dimensional surface and longitudinal side wall, the 3D electrode can carry more active material, the specific capacitance and the specific energy density are thus enhanced, the 3D comb structure active material introduction method is of great significance for the research of 3D capacitors, and the proposed packaging and integration method ensures the stability and the service life of the capacitor.

The present invention provides a high-concentration solution, which is suitable for electrolyte. The solution contains at least zinc ions, bromide ions and chloride ions. Through the action of "multi-salt co-dissolution", a new "salt-dissolving mixture" is formed, which greatly increases the concentration of the solution. . Further, the present invention also provides an ultra-high concentration solution, which also contains zinc acetate. Through the "end-capping" effect of zinc acetate, the salt cannot continue to aggregate and grow, and then it becomes an inorganic oligomer with a larger molecular weight and stably exists. In solution, its concentration can even reach 45mol kg ‑1 . The high concentration of electrolyte not only effectively inhibits the electrolysis of water, but also reduces the oxidation potential of bromide ions, which further promotes the intercalation of bromine in the battery cathode material, and greatly improves the specific capacity of the cathode (~638mAh g) ‑1 ). Moreover, the increase of the active ion concentration of the electrolyte can reduce the amount of the electrolyte, which is beneficial to the improvement of the energy density of the non-rocking-chair battery.

The invention discloses a preparation method of a lithium-sulfur battery flexible positive electrode. The flexible positive electrode is formed by dispersing nitrogen-doped porous carbon fibers loaded with S<1-x>Sex among graphene sheet layers. The preparation method comprises the following steps: first compounding sulfur and selenium with nitrogen-doped porous carbon fibers to form a nitrogen-doped porous carbon fiber / S<1-x>Sex composite material, then adding the nitrogen-doped porous carbon fiber / S<1-x>Sex composite material into solvent, ultrasonically dispersing the solvent to obtain graphene and nitrogen-doped porous carbon fiber / S<1-x>Sex composite material composite suspension, vacuum suction filtering the composite suspension to obtain a filter cake, and drying the filter cake to obtain the flexible positive electrode of the graphene / nitrogen-doped porous carbon fiber / S<1-x>Sex composite material. The lithium-sulfur battery flexible positive electrode obtained by virtue of the preparation method has advantages of good conductivity, good sulfur and selenium fixing effect, high mechanical strength and the like. Meanwhile, the preparation method is simple, no complicated coating process is needed, no adhesive, conducting agent and current collector is needed, and the prepared flexible positive electrode is applied to a lithium-sulfur battery and has excellent electrochemical performance.