1452 results about "Lithium dendrite" patented technology

The invention discloses a composite diaphragm for a battery and a preparation method thereof, belonging to the field of electrochemical cells. The composite diaphragm is a multilayer composite diaphragm structure composed of a conducting layer / a polymer layer or a conducting layer / a polymer layer / a conducting layer, wherein the conducting layer mainly comprises a carbon material or a conductive polymeric material and forms a film on a single surface or double surfaces of a polymer diaphragm. The composite diaphragm has the following characteristics: the conducting layer has strong electrolyte adsorption and storage capability, the process of ion transport is shortened, and large-current charge and discharge performance of the battery is improved; when the composite diaphragm is used in a metallic lithium battery, the conducting layer in the composite diaphragm contacting with metallic lithium can alleviate nonuniform corrosion on the surface of lithium and inhibit formation of lithium dendrite crystals. The preparation method for the composite diaphragm is simple and easily controllable, can realize large-quantity and low-cost industrial preparation of the composite diaphragm and has a high application value.

The invention relates to a method for protecting anode of a lithium sulfur battery. A diaphragm functional protective coating can be used for effectively suppressing the generation of lithium dendrites on the surface of a lithium anode, improving the safety of the battery and prolonging the cycle life of the battery, and slurry mixing is carried out by controlling the types and the proportion of a carrier, an adhesive, an additive and the like of the coating to prepare a diaphragm with the functional protective coating for protecting the lithium anode. The operation process is simple, and the protective layer can be used for effectively suppressing the generation of the lithium dendrites; and meanwhile, the additive is continuously released from the carrier, a layer of the protective diaphragm is continuously formed on the surface of the lithium anode to protect the lithium anode, and the safety and the cycling performance of the lithium sulfur battery are further improved.

The invention relates to solid-state electrolytes, in particular to a polycarbonate all-solid-state polymer electrolyte, an all-solid-state secondary lithium battery made of the same and preparation and application thereof. The all-solid-state polymer electrolyte is prepared from polycarbonate macromolecules, lithium salt and a porous supporting material; the thickness is 20-800 micrometers, the mechanical strength is 10-80 MPa, the room temperature ion conductivity is 2*10<-5>S / cm-1*10<-3>S / cm, and the electrochemical window is higher than 4V. The all-solid-state polymer electrolyte is easy to prepare and form, good in mechanical property, high in ion conductivity and wide in electrochemical window; meanwhile, the solid-state electrolyte effectively inhibits growth of negative electrode lithium dendrites and improves interface stability and long circulation performance.

The invention discloses a preparation method of a composite lithium metal anode and belongs to the technical field of lithium metal batteries. The preparation method of the composite lithium metal anode comprises steps as follows: firstly, the surface of a framework material is modified, the framework material with the lithiophilic surface is prepared, the framework material is contacted with liquid metal lithium, so that the liquid metal lithium is injected into the framework material with the lithiophilic surface, and the composite lithium metal anode is prepared after cooling. The lithiophilic surface can be obtained through modification of various framework materials (including a conductive framework material and an insulated framework material), the framework materials are efficientlycomposited with the liquid metal lithium, and the composite lithium metal anode material is obtained. When the obtained composite lithium metal anode material is assembled in a total battery, growthof lithium dendrites can be effectively inhibited, the volume expansion effect of the anode is relieved, the pulverization phenomenon of the lithium metal anode is reduced, and the cycling stability and the safety of the lithium metal battery are substantially improved, and the cycle life of the lithium metal battery is substantially prolonged.

The present invention discloses a preparation method of a complex lithium negative pole of a solid state battery, and belongs to the technical field of electrochemistry and new energy resources. The preparation method mainly comprises the steps: depositing lithium metal on three-dimensional carbon material or foam porous material gaps by using a heat infusing melting method or an electrodeposition method to obtain the complex lithium negative pole, wherein the application of a three-dimensional framework plays two roles, namely, providing adequate space for pre-storing lithium in the preparation process; providing a carrier for receiving metal lithium in a battery circulation process. The complex lithium negative pole can be widely applied in lithium metal batteries such as lithium ion batteries, lithium-air batteries, lithium-sulfur batteries, and solid state batteries. In the assembled symmetric solid state battery, under large electric current density of 5mA cm-2, a stable voltage decay (200mV) can still be kept after circulation for 100 times, in the battery circulation, the growth of lithium dendrites can be inhibited and the pole volume change can be stabilized, and the advantages of being good in circulation stability, and long service life can be realized; in the present invention, a carrier material is rich, and low in price; the process is controlled, the cost is low, and the batch production can be realized.

The present invention provides a composite quasi-solid-state electrolyte, a composite quasi-solid-state electrolyte membrane, preparation methods of composite quasi-solid-state electrolyte and the composite quasi-solid-state electrolyte membrane, and a lithium battery or a lithium ion battery containing the composite quasi-solid-state electrolyte membrane. The composite quasi-solid-state electrolyte comprises a solid electrolyte, a lithium salt-containing liquid electrolyte, inorganic nanoparticles and a binder, wherein the static electricity or functional groups on the surface of the inorganic nanoparticles can adsorb the electrolyte so as to make the composite quasi-solid-state electrolyte have strong adsorption capacity and strong liquid retention ability, and the inorganic nanoparticles can adsorb the lithium salt so as to change the lithium ion conduction mechanism, reduce the interfacial resistance between the liquid electrolyte and the solid-state electrolyte, change the deposition morphology of lithium, hinder the formation of lithium dendrite, and reduce the pulverization of lithium. In addition, by adding the solid electrolyte, the composite quasi-solid-state electrolyteof the present invention can maintain the high conductivity and can effectively reduce the content of the liquid electrolyte so as to improve the safety of the battery.

The invention discloses a modified diaphragm. The modified diaphragm comprises a diaphragm substrate, and an electronic conductive coating layer and an inorganic hard coating layer positioned on the two surfaces of the diaphragm substrate respectively, wherein the electronic conductive coating layer is a mixed coating layer with graphene and a porous carbon material; and the inorganic hard coating layer is a nitrogen-carbon material coating layer, a nitrogen-silicon material coating layer, a carbon-boron material coating layer or a silicon-carbon material coating layer. The preparation method comprises the steps of uniformly coating the two surfaces of the diaphragm substrate with the electronic conductive coating layer and the inorganic hard coating layer respectively, and drying the two surfaces respectively obtain the modified diaphragm. The modified diaphragm has high diffusion and absorption capacity for an organic electrolyte, high ionic conductivity, and an obvious adsorption and blocking effect on poly-sulfur-lithium; in addition, the modified diaphragm can further restrain a shuttle effect, prevent battery short-circuit, effectively restrain the growth of negative electrode metal lithium dendrites in a cyclic process, prevent from punching the diaphragm, and protect the lithium negative electrode, so that the problem that the diaphragm is punched after dendrites formation is solved, and the safety performance of the battery is improved.

The present disclosure relates to a lithium electrode, comprising an electrode composite comprising a porous metallic current collector, and lithium metal inserted into pores present in the metallic current collector; and a protective membrane for lithium ion conduction, the protective membrane being formed on at least one surface of the electrode composite.The lithium electrode according to the present disclosure can increase contact surface between lithium metal and a current collector to improve the performances of a lithium secondary battery, and can exhibit uniform electron distribution therein to prevent the growth of lithium dendrites during the operation of a lithium secondary battery, thereby improving the safety of a lithium secondary battery. Furthermore, even though the lithium electrode is coated with a protective membrane for lithium ion conduction on the surface thereof, the protective membrane can be prevented from being peeled off during the charge and discharge of a lithium secondary battery.

The invention relates to an organic and inorganic composite all-solid-state electrolyte, in particular to an organic polycarbonate macromolecule and inorganic fast-ion conductor composite all-solid-state electrode and preparation and application of an all-solid-state battery formed from the same. The organic and inorganic composite all-solid-state electrolyte comprises polycarbonate macromolecule, an inorganic fast-ion conductor, a lithium salt and a porous rigid support material, the thickness of the organic and inorganic composite all-solid-state electrolyte is 5-2,000 micrometers, the mechanical strength is 2-150MPa, the room-temperature ionic conductivity is 1*10<-4>-6*10<-3> S / cm, and an electrochemical window is greater than 4V. The organic and inorganic composite all-solid-state electrolyte provided by the invention is easy to prepare and simple to form, has favorable mechanical property, and is relatively high in room-temperature ionic conductivity and relatively wide in electrochemical window; and meanwhile, by the organic and inorganic composite all-solid-state electrolyte, the growth of lithium dendrites of a negative electrode can be effectively prevented, the interface stability is improved, and the long-circulation and safe application performance of the battery are further improved.

The invention discloses a lithium anode with an inorganic protective coating and a preparation method thereof. The lithium anode includes a lithium anode active substance and an inorganic protective coating that covers the same, wherein the lithium anode active substance is lithium metal or lithium alloy; the inorganic protective coating is prepared from a binder and a lithium ion conductor inorganic compound or an inorganic compound that may generate a lithium ion conductor in situ on the surface of the lithium anode. A layer of stable compact inorganic protective film is prepared on the surface of the lithium anode active material by means of direct coating which is simple and low in cost, side reaction between the lithium anode active material and electrolyte is inhibited, uniform deposition of lithium ion is promoted, growth of lithium dendrite is slowed, and safety of the lithium anode is improved. The lithium anode prepared herein has excellent cycle performance, and a new concept for the application of the lithium anode is provided.

A standalone lithium ion-conductive solid electrolyte including a freestanding inorganic vitreous sheet of sulfide-based lithium ion conducting glass is capable of high performance in a lithium metal battery by providing a high degree of lithium ion conductivity while being highly resistant to the initiation and / or propagation of lithium dendrites. Such an electrolyte is also itself manufacturable, and readily adaptable for battery cell and cell component manufacture, in a cost-effective, scalable manner.

The invention discloses an organic-inorganic composite electrolyte membrane having a double layer structure including a first layer and a second layer, wherein each of the first layer and the second layer is prepared from slurry comprising the following same components: an inorganic solid electrolyte, lithium salt, a film forming agent, a conductive lithium ion polymer, a plasticizer, and a solvent; herein, the content of inorganic solid electrolyte in the first layer is higher than that in the second layer, and the content of conductive lithium ion polymer in the first layer is less than thatin the second layer. The invention also discloses a battery having the organic-inorganic composite electrolyte membrane. The membrane has good flexibility and high conductivity, can satisfy differentdemands of a cathode and an anode in a lithium ion battery at the same time, can inhibit growth of lithium dendrites, and improves comprehensive performance of the battery.

The invention discloses a high voltage-resistant multi-stage structure composite solid-state electrolyte and its preparation method and use in a solid-state lithium battery. The lithium battery utilizes a multi-stage structure solid-state electrolyte containing different components. A polymer electrolyte with excellent electrode interface compatibility is used as an electrolyte in the negative electrode side. A high voltage-resistant polymer electrolyte is used as an electrolyte in the positive electrode side. A polymer electrolyte or an inorganic electrolyte with high ionic conductivity is used as a middle layer. The multi-stage structure solid-state electrolyte has advantages such as high mechanical properties, high ionic conductivity, a wide electrochemical window, excellent electrode interfacial compatibility and lithium dendrite growth inhibition of different components. Compared with the traditional liquid lithium ion battery, the battery with the multi-stage composite solid-state electrolyte has higher safety and higher energy density.

The invention provides a composite solid electrolyte and a preparation method thereof, a flexible all-solid-state battery and a preparation method of the flexible all-solid-state battery and a wearable electronic device. The composite solid electrolyte comprises a ceramic-based solid electrolyte and a first polymer-based solid electrolyte, wherein the content of the ceramic-based solid electrolyte is 20-90wt% of total weight of the composite solid electrolyte. The composite solid electrolyte provided by the invention has good mechanical property, high ionic conductivity at a room temperature, good heat stability and electrochemical stability and high safety and can be effectively prevented from being perforated by lithium dendrites, and a good interface contact is formed by the composite solid electrolyte and a composite positive electrode, thereby obtaining the flexible all-solid-state battery which is high in area specific capacity and energy density, relatively small in battery internal resistance and high in flexibility and can be bent and cut and of which use is not affected.

The invention relates to a metal lithium negative electrode with organic and inorganic dual protection layers. The invention belongs to the technical field of electrochemistry, and relates to the metal lithium negative electrode with the organic and inorganic dual protection layers and application of the metal lithium negative electrode in a secondary lithium battery. The protection layers are characterized in that an organic protection layer is built on a surface of the metal lithium negative electrode from one or more of acrylate containing amino, cyan, nitro or nitroso, one or more of acrylic organic matters except several types of the acrylates and one or more of small molecule compounds containing nitrogen, meanwhile, a nitrogen-containing part in the organic layer reacts with metal lithium to form an inorganic protection layer at an interface in an in-situ way, so that the organic and inorganic dual protection layers are formed. When the metal lithium negative electrode with the protection layers is applied to a lithium battery, the coulombic efficiency of the battery can be effectively improved by a synergistic effect of the organic layer and the inorganic layer, the growth of lithium dendrites is prevented, the safety problem is improved, and the cycle lifetime is prolonged.

The invention provides a solid-state composite metal lithium negative electrode. The solid-state composite metal lithium negative electrode consists of a composite layer and a solid-state electrolyteprotecting layer, wherein the composite layer consists of metal lithium and lithium-favoring framework material; the solid-state electrolyte protecting layer comprises an inorganic solid-state electrolyte and an organic solid-state electrolyte; the composite layer of metal lithium and lithium-favoring framework material is provided by melting and lithium filling, electrochemical deposition or physical and mechanical mixing; the solid-state electrolyte protecting layer is applied to the surface of the composite layer by impregnating, scrape coating, rotary coating, spray coating or spattering.Compared with the common lithium piece negative electrode, the solid-state composite metal lithium negative electrode has the advantages that the problem of volume expansion of the negative electrodeis relieved, the deposition behavior of the metal lithium can be regulated and controlled, the growth of lithium dendrites can be inhibited, the safety property of a metal lithium battery is improved,and the cycle life of the metal lithium battery is prolonged; in the testing process of a lithium and copper semi-battery, the volume is expanded by 1 to 20% in the charge and discharge process, theobvious dendrites do not occur in the 20 to 5000 cycles of the battery, and the utilization rate is increased to 80 to 99.9999%.

The invention belongs to the technical field of a lithium secondary battery, and particularly relates to a porous copper current collector, capable of retraining generation of lithium dendrites, of the metal lithium secondary battery. The porous copper current collector has a connected porous channel structure, and the pore diameter is 0.1-2[mu]m. Compared with the prior art, the three-dimensional porous structure can lower the effective current density of the electrode by enlarging the specific surface area of the electrode so as to restrain the generation of lithium dendrites and to stabilize the SEI film; in addition, the three-dimensional porous structure can accommodate the deposited lithium metal so as to slow down the volume change of the lithium metal negative electrode in the charging-discharging cyclic process; and therefore, when the three-dimensional porous copper current collector is applied to the negative electrode of the metal lithium secondary battery, the coulombic efficiency, the circulating stability and the safety of the battery can be effectively improved in the cyclic process.

The invention provides a composite porous current collector, and a preparation method and an application thereof. The composite porous current collector comprises a porous electron conducting layer with through holes and an electron insulating layer with through holes, wherein the porosity of the through holes of porous electron conducting layer is not less than the porosity of the through holes of the electron insulating layer, a position of the porous electron conducting layer corresponding to the position of the through hole of the electron insulating layer is a through hole, and a position of the porous electron conducting layer corresponding to the position of the non-through hole of the electron insulating layer can be a through hole, and also can be a blind hole or a rough surface. The electron insulating layer is adjacent to an isolation layer, so puncture of precipitated lithium dendrite to a diaphragm is prevented, direct contact of the electron conducting layer is avoided, and the safety of a battery is improved; the above corresponding through hole structure is in favor of transferring lithium ions, so the internal resistance of the battery is reduced; the hole structure of the porous electron conducting layer and the homogeneous rough surface are in favor of full contact of an electrode active substance with the current collector, the current is uniformly distributed, and the current collection effect is improved; and the preparation method adopting airflow punching has the advantages of simplicity, easy implementation, cleanness, energy saving, combination of other various enforcement modes, and convenience for production and application.

The invention discloses a metal lithium negative electrode piece, a preparation method thereof and a metal lithium secondary battery. The metal lithium negative electrode piece comprises a current collector, wherein a metal lithium layer is formed on the current collector; a composite conductive film is formed on the metal lithium layer. The preparation method of the metal lithium negative electrode piece comprises the following steps: laminating a metal lithium foil and the current collector together, or plating lithium metal on the surface of the current collector; dissolving a polymer electrolyte in a solvent to prepare a polymer electrolyte solution; adding a conductive agent into the polymer electrolyte solution; stirring uniformly and then coating a mixed solution on the metal lithium layer; after evaporating the solvent, forming the composite conductive film on the surface of the metal lithium layer to obtain the metal lithium negative electrode piece; or, coating the mixed solution on a substrate and evaporating the solvent to obtain the composite conductive film, laminating the composite conductive film on the surface of the metal lithium layer to form the composite conductive film and obtain the metal lithium negative electrode piece. The metal lithium negative electrode piece provided by the invention can inhibit lithium dendrites, prevent batteries from being short-circuited, and improve safety performance and cycling performance of lithium batteries.

The invention discloses an anode material for a lithium metal battery. The anode material comprises a current collector and a carrier which is in tight fit with the current collector, wherein the carrier has a three-dimensional framework structure; a gap of the three-dimensional framework structure is filled with lithium metal; the carrier is selected from at least one of polymelamine, polyacrylonitrile, polyaniline, polyimide, polyvinylidene fluoride and polytetrafluoroethylene. The anode material disclosed by the invention has the advantages that a nonconductive polymer with the three-dimensional framework structure is used as the carrier, and stable deposition of lithium ions is realized by using interaction of functional groups contained in the carrier and the lithium ions; meanwhile,volumetric expansion is inhibited, internal stress of the battery is relieved, and thereby the aim of inhibiting growth of lithium dendrites is achieved. The coulombic efficiency, the safety of the lithium ion battery obtained by assembling the anode material prepared disclosed by the invention is remarkably improved and cycle life is obviously prolonged.

The invention relates to a metal lithium anode with a protective coating and a preparation method based on molecule layer-by-layer self-assembly. The substance of the coating is a solid electrolyte interface membrane constructed by an assembling molecule layer and an inorganic fast ion conductor layer on an active material layer surface of the metal lithium anode. The solid electrolyte interface membrane has the following functions: (1) electrolyte solution and lithium wafers are effectively isolated and the lithium wafers are prevented from being eroded and reacted; (2) lithium ions are uniformly distributed and generation of lithium dendrites is restrained; (3) inorganic fast ion conductors can transmit the lithium ions, and membrane strength is effectively improved. Metal lithium electrode pieces protected by the protective coating are used in lithium batteries, the coulombic efficiency of the batteries can be effectively improved, and circulation life is prolonged.

The present invention discloses an inorganic-organic nano composite solid electrolyte membrane and a preparation method and application thereof. The composite solid electrolyte is a novel inorganic-organic nanocomposite combining the respective advantages of inorganic ceramic solid electrolyte and organic polymer electrolyte and is composed of a negative electrode protective layer, a support layerand a positive electrode interface layer. The support layer plays a supporting role, and the main component of the negative electrode protective layer is the inorganic solid electrolyte with good mechanical properties, which can effectively inhibit the growth of lithium dendrite; and the positive electrode interface layer is mainly composed of organic polymer electrolyte with good flexibility, ensures good contact with active materials and provides a continuous ion transport channel. In the present invention, the composite solid electrolyte with good interface compatibility is prepared by coating on both sides of the support layer, and the process is simple and efficient. The composite solid electrolyte can effectively inhibit dendritic crystal and reduces interface resistance so that a solid lithium metal battery has higher energy density and longer cycle life.

The invention provides a membrane and a preparation method thereof as well as a lithium ion battery. The membrane comprises a substrate and size layers arranged on two sides of the substrate, wherein the size layers comprise ceramic particles, a silane coupling agent and an adhesion agent, and the substrate is an insulating carbon fiber non-woven fabric. The membrane disclosed by the invention has the advantages of good heat-resistant property, chemical corrosion resistant property, high strength and capability of effectively avoiding short circuit in the battery caused by puncture of lithium dendrites. The lithium ion battery prepared from the membrane disclosed by the invention has the advantages of excellent safety performance and high temperature resistance and long service life.

The present invention relates to a negative electrode including a multi-protective layer and a lithium secondary battery including the same, and the multi-protective layer prevents lithium dendrite growth on a surface of the electrode, and does not cause overpotential during charge and discharge since the protective layer itself does not function as a resistive layer, and therefore, is capable of preventing battery performance decline and securing stability when operating a battery.

The invention discloses a high-power lithium ion power battery, comprising a plurality of single electrical cores connected in parallel. Each single electrical core consists of an anode plate, a cathode plate, a separator film, and two to eight anode tabs and cathode tabs. The anode tabs and the anode plate are integrated as a whole which is punched on the aluminum foil of the current collector of the anode; the cathode tabs and the cathode plate are integrated as a whole which is punched on the copper foil of the current collector of the cathode. All the tabs of the anodes of the single electrical cores are welded on a positive pole, while all the tabs of the cathodes are welded on a negative pole. By the structure of a variety of single electrical cores connected in parallel and a plurality of tabs integrated as a whole, the high-power lithium ion power battery leads the total essential resistances of the batteries to be further reduced and the currents of the anode and cathode plates to be distributed more uniformly, as a result, the high-power lithium ion power battery has the advantages of small essential resistances in total, high discharge rate, lower possibility of forming lithium dendrites, long cycle life and high specific power etc., and is widely used in electric vehicles, electric tools and other equipment in need of high-power batteries.

The invention discloses a lithium metal battery lithium negative electrode surface modification method, and a lithium metal battery. The modification method comprises the following steps: a lithium metal negative electrode is impregnated in or coated with a fluorine-containing ionic liquid in a dry protection gas atmosphere, is fluorinated, and is taken out to make a protection layer rich in lithium fluoride formed on the surface of the metal lithium negative electrode in order to obtain a lithium fluoride coated metal lithium negative electrode. The lithium fluoride protection layer obtainedby surface fluorination is very uniform and dense, and can reduce the consumption of lithium metal and an electrolyte and inhibit the formation of lithium dendrites in order to make the metal lithiumnegative electrode have a high specific discharge capacity, a long cycle life and a good safety, so the stability and the high efficiency of the lithium metal battery in a long cycle process are achieved, use requirements of a high-energy and high-power power battery are met, the industrialization process of the lithium metal battery is facilitated, and lithium metal battery has a wide applicationprospect.

The invention discloses a battery diaphragm with high-temperature-resistant metal-organic frame material coating, and a preparation method and application thereof. The battery diaphragm takes a commercial diaphragm as the substrate, and the single surface or double surface is coated with the metal-organic frame material. Compared with the prior art, the battery diaphragm disclosed by the inventionhas the following advantages: the metal-organic frame material coating is high in porosity and large in specific area, and the electrolyte wetting property of the diaphragm can be improved; the metalorganic frame material coating can effectively improve the heat-insulating property of the diaphragm, and improve the safety performance of the battery in the high-temperature environment; the metal-organic frame material coating can effectively control the shuttle of the electrolyte ion, improve the ion transport number, restrain the bad and side effect, improve the battery capacity, and prolongthe circulating life; the uniform duct structure enables the lithium ions to be uniformly deposited / peeled, thereby fundamentally restraining the growth of the lithium dendrites; the battery diaphragm disclosed by the invention has good flexibility and mechanical performance, and can be used for assembling a practical soft-package battery.

The invention belongs to the field of lithium batteries, and discloses preparation and application of a lithium metal anode with a composite film. The preparation method comprises the following stepsof: (1) performing matching and composite load of an organic component and an inorganic lithium compound component according to the mass ratio of 1:1-98:1 on a current collector; and (2) assembling the obtained current collector with the surface coated with a composite film with a lithium sheet into a battery for electrochemical deposition to deposit the metal lithium on the current collector withthe surface coated with the composite film so as to obtain a lithium metal anode material with a composite film. According to the invention, the lithium metal anode material with the composite film is obtained by improving the overall design of the flow process of the anode material preparation method, the phenomenon of lithium dendrite caused by uneven deposition in the circulation process of the conventional lithium metal anode and the phenomenon of reduced circulation performance caused by dead lithium generated by the reaction of the lithium metal anode and electrolyte can be solved, andthe lithium metal anode material can be used as the anode in a lithium metal battery, so that the circulation life of the lithium metal battery is prolonged.

The invention relates to a production method of a boron nitride coated diaphragm of a lithium-sulfur battery. The diaphragm is produced from a commercial polypropylene diaphragm, two sides of the diaphragm are uniformly covered with hexagonal boron nitride, and the characteristics of hexagonal boron nitride 'white graphite' are used, so lithium ions are allowed to pass, shuttle of polysulfide anions is obstructed, a reaction of a lithium negative electrode with the polysulfide anions is inhibited, formation of lithium dendrites, lithium sulfide precipitate and fixed lithium is prevented, the capacity, the coulombic efficiency and the cycle stability of the lithium-sulfur battery are improved, the growth of the negative electrode metal dendrite in the cycle process is effectively inhibited, and the safety of the battery is improved. The method has the advantages of simple process route and clear purpose, and the produced diaphragm has multiple functions, and can greatly overcome disadvantages of present technologies.