715 results about "Lithium dendrite" patented technology

The invention discloses a high-interface-stability composite solid electrolyte membrane as well as a preparation method and application thereof. The composite solid electrolyte membrane comprises a gradient aperture three-dimensional porous skeleton formed by sintering inorganic solid electrolyte particles, a polymer electrolyte filled in a pore channel, and a plastic interface stable layer positioned between the electrolyte membrane and an electrode. The preparation method comprises the following steps: preparing a gradient aperture porous framework through a pore-forming agent template method and a tape casting technology, dipping and filling a polymer electrolyte precursor solution in a solution, accelerating in-situ polymerization by adopting electric induction, and performing hot-pressing treatment. The composite solid-state electrolyte membrane has high ionic conductivity, excellent interface compatibility and high mechanical strength, can effectively inhibit the growth of lithium dendrites, can be applied to solid-state batteries such as lithium metal batteries, lithium sulfur batteries and lithium air batteries, and can remarkably prolong the cycle life and improve the safety performance of the batteries, and the preparation process is suitable for large-scale production.

The invention provides a fast-charging type solid-state lithium battery alloy negative electrode material, a preparation method and a solid-state lithium battery, and relates to the technical field of lithium batteries. The alloy negative electrode material comprises the following element components in percentage by mass: 30-38% of indium In, 30-35% of tin Sn, 28-35% of bismuth Bi and 0-1.5% of doping elements, crystal phases formed by the alloy negative electrode material of the fast-charging type solid-state lithium battery at least comprise two crystal phases, namely InSn4 and InBi. The alloy negative electrode material has relatively high surface capacity, lithium ion conductivity and lithium ion diffusion coefficient, lithium dendrites do not grow on a negative electrode when a solid-state lithium battery assembled by the alloy negative electrode material is charged and discharged under high current density, and the battery is high in energy density and long in cycle life.

The invention belongs to the technical field of batteries, and particularly relates to a negative electrode material, a secondary battery and electric equipment. The second coating layer with the porous carbon material in the negative electrode material provides a sufficient buffer space for volume expansion of silicon, so that cracks and pulverization of the negative electrode material are effectively reduced, and the structural integrity of the negative electrode material is further ensured. And meanwhile, the solid electrolyte arranged in the second coating layer can maintain the smoothness of an ion transmission path in the silicon expansion process, so that the rate capability and the quick charge performance of the battery are ensured. Besides, a third coating layer (SEI film) formed by the ionic liquid has good ionic conductivity, and dynamic covalent bonds existing in some ionic liquids can be fractured and recombined under the action of external stress, so that a self-repairing function is realized. Therefore, when cracks are generated on the surface of the negative electrode material due to volume expansion, the third coating layer can quickly repair the cracks, prevent electrolyte permeation and lithium dendrite growth and inhibit side reactions.

The invention relates to the technical field of new energy automobile and battery safety, and discloses a power battery thermal runaway risk early warning method, which comprises the following steps: synchronously acquiring battery internal resistance dynamic change, characteristic gas concentration and temperature gradient distribution through a multi-physics field coupling sensor network, and constructing an electrochemical-thermal-gas ternary early criterion; the internal resistance mutation rate is calculated through self-adaptive sliding window differential, the gas precipitation rate and the temperature space heterogeneity index are combined and input into a multi-branch fusion neural network containing a gating attention mechanism, the continuous thermal runaway risk probability is output, and corresponding early warning is triggered according to grading threshold values. The system comprises an internal resistance, gas and temperature monitoring module and a multi-modal fusion evaluation and grading early warning execution module. According to the method, the traditional early warning logic singly depending on a temperature threshold value is abandoned, a ternary early criterion system with the internal resistance abrupt change rate, the characteristic gas precipitation rate and the temperature space heterogeneity index as the core is constructed for the first time, and electrochemical and physical field anomalies caused by thermal runaway precursor events such as lithium dendrite piercing of a diaphragm and SEI membrane rupture can be effectively captured.

The invention discloses a composite solid electrolyte and a preparation method and application thereof, and belongs to the technical field of solid lithium batteries. The composite solid electrolyte comprises a polymer matrix, a lithium salt and a lithium ion modified ionic metal organic framework (MOF) material. The metal center of the ion-conducting MOF material can be selected from Zr, Ti, Hf and the like, and the organic ligand can be selected from organic acids containing sulfydryl, sulfo groups and the like. The MOF material can effectively inhibit crystallization of a polymer matrix and increase the proportion of an amorphous region, Lewis acid sites on the surface of the MOF material can promote dissociation of lithium salt, and a lithium ion coordination channel formed in the MOF material can provide an extra rapid transmission path for lithium ions. When the electrolyte is applied to the solid-state lithium battery, the growth of lithium dendrites can be effectively inhibited, and the rate capability, the cycling stability and the safety of the battery can be remarkably improved.

The invention discloses a tantalum-doped lithium metal composite negative electrode and a preparation method thereof. The preparation method comprises the following steps: melting solid-state lithium metal into liquid-state lithium metal; the tantalum metal is added into the liquid lithium metal to be mixed and stirred, the tantalum-doped lithium metal composite material is obtained after standing and cooling, and the adding amount of the tantalum metal is 0.1-10 wt% of the mass of the liquid lithium metal; and rolling the tantalum-doped lithium metal composite material to obtain the tantalum-doped lithium metal composite negative electrode, so that the tantalum is introduced into the lithium metal through a melt doping process, and the formed tantalum-doped lithium metal composite negative electrode can inhibit the growth of lithium dendrites and prolong the cycle life of the battery.

The invention discloses a preparation method and application of a composite PVDF-HFP and polylysine nanofiber diaphragm, and belongs to the technical field of lithium batteries. The composite material is prepared by blending polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) and polylysine and then carrying out an electrostatic spinning process. The PVDF-HFP is utilized to provide excellent mechanical strength and chemical stability, rich polar amino functional groups in a polylysine molecular chain are utilized to improve the lyophilic property of the membrane, and anions in an electrolyte are fixed through an intermolecular acting force, so that the transference number of lithium ions is increased, and the lithium ions are induced to be uniformly deposited. The nanofiber membrane combines the characteristics of PVDF-HFP and polylysine, has high porosity, good thermal stability and excellent interface compatibility, can effectively inhibit the growth of lithium dendrites and prevent the diaphragm from being punctured, and can significantly prolong the cycle life and improve the safety performance of the lithium metal battery when being applied to the lithium metal battery.

The invention belongs to the technical field of all-solid-state sulfide lithium metal batteries, and relates to a lithium battery electrode containing an interface self-repairing coating as well as a preparation method and application of the lithium battery electrode. The electrode comprises a lithium metal negative electrode substrate and the interface self-repairing coating coated on the surface of the lithium metal negative electrode substrate, the interface self-repairing coating is internally provided with a dynamic reversible network, and the dynamic reversible network is constructed by disulfide bonds and hydrogen bonds. A layer of interface self-repairing coating is formed on the surface of a lithium metal negative electrode substrate to serve as a physical isolation barrier, metal lithium and sulfide electrolyte are isolated and prevented from being directly subjected to reduction reaction, and coating microcracks generated by volume change in lithium metal circulation can be repaired, so that the possibility of interface exposure caused by coating breakage is reduced, and the service life of the lithium metal negative electrode is prolonged. Meanwhile, good interface contact can be kept, the synergistic effect of stable interface impedance, lithium dendrite inhibition and long-term cycle performance improvement is achieved, and the long-term cycle stability of the all-solid-state lithium battery is improved.

The application belongs to the technical field of lithium ion batteries, and relates to a solid-state electrolyte interface layer for a lithium metal negative electrode and an in-situ plasma construction method and application thereof. The core of the method is to use an organic-inorganic-alloy component precursor as a plasma reaction source, to control the mixing ratio and reaction conditions to perform plasma reaction on the surface of lithium metal, and to in-situ construct a unique gradient layered structure of an organic-inorganic-alloy composite artificial solid-state electrolyte interface layer. The outer layer of the solid-state electrolyte interface layer is a flexible organic phase, the middle layer is a rigid inorganic fast ion conductor, and the inner layer is a lithiumophilic alloy phase, which can synergistically inhibit lithium dendrite growth and significantly improve the interface stability of the lithium metal negative electrode. Meanwhile, the preparation method provided by the application is simple, rapid, efficient, environmentally friendly, mild in conditions and easy to control, significantly improves the cycle stability and coulombic efficiency of the lithium metal negative electrode, and is helpful to promote the development of high-energy-density lithium metal batteries.

The invention relates to a covalent organic framework modified cellulose nanofiber composite diaphragm which is characterized in that cellulose nanofiber is used as a matrix, an amide type or amine type covalent organic framework layer is grown on the surface in situ, the loading capacity of a covalent organic framework is regulated and controlled, and a hierarchical pore structure with gradient pore diameter is constructed; the preparation method comprises the following steps: synthesizing a covalent organic framework precursor bonded with an imine bond on the surface of cellulose nanofiber in situ by a one-pot method under an acidic mixed solution and a heating condition, and regulating and synchronously reducing to convert into an amine type covalent organic framework; or after the imine bond bonded covalent organic framework is synthesized in two stages, the imine bond bonded covalent organic framework is selectively converted into an amide type covalent organic framework through oxidation modification; the obtained cellulose nanofiber compound coated with the covalent organic framework is subjected to the processes of film forming, solvent replacement, supercritical drying and the like, and the composite diaphragm is obtained; the diaphragm has excellent electrolyte wettability, high liquid absorption rate, good ionic conductivity and thermal stability, and can promote uniform transmission of lithium ions and inhibit growth of lithium dendrites.

The invention relates to the field of batteries, and particularly discloses a composite diaphragm of an asymmetric bifunctional coating, a preparation method of the composite diaphragm and a lithium ion battery. The lithium ion battery comprises a positive pole piece, a negative pole piece and a composite diaphragm with a bifunctional coating. Wherein the composite diaphragm with the dual-function coating comprises a base diaphragm, a positive electrode side functional layer and a negative electrode side functional layer, the positive electrode side functional layer comprises a metal organic framework (MOF) material, dissolution of metal ions of a positive electrode material can be effectively inhibited by virtue of an aperture effect, and electrolyte infiltration and liquid retention capabilities are improved; and the negative electrode side functional layer comprises MOF, a polymer and an inorganic filler, and can absorb electrolyte, regulate and control lithium ion distribution and inhibit lithium dendrite growth. The functional layers on the two sides can significantly improve the safety performance and lithium ion transmission dynamics of the diaphragm, and prolong the cycle life of the battery. Therefore, the lithium ion battery disclosed by the invention realizes high energy density, long cycle life and high safety.

The invention discloses a polymer solid electrolyte, which is composed of the following components: a polymer substrate; a lithium salt; the composite filler is IL (at) ZIF-67 formed by compounding ZIF-67 and an ionic liquid; and a solvent. The ionic liquid is used as a plasticizer, and the EmimTFSI can effectively weaken the intermolecular acting force between polymer chains and increase the free volume and movement ability of the polymer chains. ZIF-67 has abundant Lewis acid sites (Co < + >), and the sites can form weak coordination with LiTFSI, so that the ionic conductivity is further improved. The introduction of the composite filler is beneficial to improving the interface stability of the polymer electrolyte and the lithium metal negative electrode and inhibiting the growth of lithium dendrites, so that the cycle life of the battery is prolonged. The polymer solid electrolyte membrane prepared on the basis of the preparation method is applied to a solid-state lithium-sulfur battery, and the cycling stability, the rate capability and the coulombic efficiency of the battery can be remarkably improved.

The invention provides a supercritical lithium metal battery electrolyte with electric field adaptability and application, and belongs to the technical field of lithium metal batteries. Comprising a lithium salt, a main solvent and a diluent, has the characteristic of adaptively stabilizing a lithium metal negative electrode under the action of an electric field, and is a supercritical state electrolyte obtained by dissolving the lithium salt in the main solvent to form a solution with the concentration being greater than or equal to 5 mol / L and diluting the solution with the diluent; the main solvent is at least one of chain ester, chain ether and siloxane, the diluent is hydrofluoroether, and the volume ratio of the main solvent to the diluent is 1: (0.5-20). The lithium metal negative electrode shows stable self-adaptive capacity under the action of an electric field, and formation of lithium dendrites is inhibited by promoting decomposition of anions at the negative electrode to form SEI rich in inorganic components, so that long-time stable circulation of a high-voltage lithium metal battery is realized.

The invention relates to the technical field of solid-state batteries, and particularly discloses an all-solid-state sulfide negative-electrode-free lithium metal battery and an assembling method thereof. The battery adopts a combination of an electrolyte membrane and electrolyte powder as an electrolyte layer, the electrolyte membrane is close to a positive electrode side, and the electrolyte powder is close to a negative electrode side. According to the structure, the compaction density and density of the electrolyte layer are remarkably improved, the growth of lithium dendrites is effectively inhibited, the interface impedance is reduced, and the volume change of the positive electrode is buffered. The assembly method comprises the following steps: compounding the positive electrode and the current collector, sequentially placing the electrolyte membrane, the electrolyte powder and the negative electrode plate, and carrying out pressure-maintaining molding under a specific pressure. Experiments show that the battery has high initial specific discharge capacity, long cycle life and high capacity retention rate, and is suitable for large-scale solid-state battery manufacturing.

The invention discloses a preparation method and application of a vertically-oriented ferroelectric ceramic-polymer composite solid electrolyte, and belongs to the field of application of solid-state lithium metal batteries. The electrolyte membrane is composed of polyvinylidene fluoride, ferroelectric ceramic powder, lithium salt and the like. The ferroelectric ceramic can form dipoles under the action of an electric field, polyvinylidene fluoride conformation is induced to be converted from an alpha phase to a beta phase, the beta conformation has large dipole moment, dissociation of lithium salt can be promoted, and more free lithium ions are generated. Through multi-solvent blending, the freezing orientation technology can be adjusted, the ferroelectric ceramic-polymer composite solid electrolyte membrane of a vertical ordered structure is prepared, and the shortest path of transmission of lithium ions between a positive electrode and a negative electrode is achieved. The vertically oriented ferroelectric ceramic-polymer composite solid electrolyte can promote lithium salt dissociation, reduce the transportation tortuosity of lithium ions and increase the ionic conductivity. The battery assembled by the material can effectively inhibit the growth of lithium dendrites, and has excellent rate capability and cycling stability.

The invention belongs to the technical field of solid-state lithium metal batteries. The invention provides a mixed ion / electron conductor intermediate layer with a directional double-layer structure. The mixed ion / electron conductor intermediate layer comprises a titanium nitride nanotube array and lithium ion conductor layers deposited on the inner surface and the upper surface of the titanium nitride nanotube array. The lithium ion conductor layer on the upper layer of the directional double-layer structure mixed ion / electron conductor intermediate layer has high lithium ion conductivity and low electron conductivity, and can inhibit nucleation of lithium on an electrolyte interface and growth of lithium dendrites; the lower layer can guide lithium to realize uniform deposition and stripping in the nanotubes through a creep mechanism, and stress is effectively released, so that the electrochemical performance of the battery is improved; the creep path of lithium deposition stripping can be shortened, and the diffusion and transmission capability of lithium ions can be remarkably enhanced by matching with a lithium ion conductor with a high lithium ion diffusion rate; the middle layer is thin and controllable in thickness, the overall energy density of the battery is hardly reduced, and the application prospect is good.

The invention relates to a preparation method of a gel polymer electrolyte and the gel polymer electrolyte, and the method comprises the following steps: dissolving a polymer matrix in a fluorinated solvent, and adding a lithium salt, an initiator and an additive into the fluorinated solvent; stirring the fluorinated solvent through an ultrasonic dispersion technology to form a homogeneous precursor solution; injecting the precursor solution into a battery shell, carrying out thermal polymerization at a preset polymerization temperature for a preset polymerization time, and forming an electrolyte membrane with a three-dimensional cross-linked network structure in the battery shell; after a residual solvent in a battery shell is removed through vacuum drying, an electrolyte membrane with a three-dimensional cross-linked network structure is used as a flexible self-supporting gel polymer electrolyte. The gel polymer electrolyte is an electrolyte membrane with a three-dimensional cross-linked network structure, can inhibit the growth of lithium dendrites and improve the ion migration efficiency, is superior to the existing electrolyte in ionic conductivity and Li < + > transference number, and is suitable for high-energy-density energy storage lithium batteries.

The invention discloses a topology enhanced three-dimensional porous framework lithium-based metal negative electrode material as well as a preparation method and application thereof, and belongs to the technical field of solid-state lithium batteries. The material comprises a three-dimensional porous conductive skeleton and an electrochemical active lithium-based phase, pores of the three-dimensional porous conductive skeleton are filled with the electrochemical active lithium-based phase, and tight physical and electrochemical contact is formed; the three-dimensional porous conductive framework is provided with a lithium-loving surface; the three-dimensional porous conductive skeleton has a Young modulus greater than 10 GPa; and the electrochemical active lithium-based phase is pure lithium metal or lithium alloy. The three-dimensional skeleton can effectively buffer the volume change of active lithium in the charging and discharging process, inhibit the growth of lithium dendrites, provide rapid lithium ion and electron transmission channels and bear external pressure. The all-solid-state lithium battery adopting the negative electrode material shows excellent cycling stability, high critical current density, high rate performance and nearly zero macroscopic volume change, and the comprehensive electrochemical performance and safety of the all-solid-state lithium battery are remarkably improved.

The invention relates to a sulfonic group modified ZIF-67 coated diaphragm as well as a preparation method and application thereof, and belongs to the technical field of lithium batteries. Comprising a porous base membrane and a modified coating coated on one side or two sides of the porous base membrane, and the modified coating comprises sulfonic group functionalized ZIF-67 nanoparticles and a binder, the sulfonic group functionalized ZIF-67 nanoparticles are a metal organic framework material formed by coordination self-assembly of a cobalt source, a 2-methylimidazole ligand and an imidazole auxiliary ligand containing a sulfonic acid group. Imidazole ligands with sulfonic acid groups are introduced into a ZIF-67 framework through in-situ coordination self-assembly, homogenization of lithium ion flux is achieved through regular pore channels of ZIF-67, meanwhile, anion decomposition is promoted through the electrostatic induction effect of the sulfonic acid groups, and the lithium ion transference number is increased. The diaphragm can effectively inhibit the growth of lithium dendrites, and shows excellent cycling stability and rate capability in an NCM811 / Li metal total battery, a Li-Li symmetric battery and a Li-Cu half battery.

The invention discloses a lithium-manganese-rich high-rate-performance electrolyte and a preparation method and application thereof. The lithium-manganese-rich high-rate-performance electrolyte comprises a lithium salt, an organic solvent and an additive, the additive is 2, 3-bis (trifluoromethyl) propynyl sulfate. According to the electrolyte disclosed by the invention, a compact and uniform CEI film is formed on the surface of a positive electrode, electrolyte oxidation and metal ion dissolution are inhibited, the cycle stability of the battery is improved, the overall oxidation resistance is improved, three-dimensional positive and negative electrode film layers are formed during film forming, and the mechanical strength is improved; the first discharge efficiency and discharge capacity of the lithium ion battery can be obviously improved, the high-temperature cycle performance is also obviously improved, side reactions are prevented, dissolution of transition metal ions is inhibited, and the cycle stability is improved. According to the invention, the growth of lithium dendrites can be effectively inhibited, the battery safety is improved, the electrolyte impedance is reduced, the battery rate and high-low temperature performance are improved, the side reaction with the electrolyte is reduced, the dissolution of transition metal ions at the positive electrode side is inhibited, the gas production rate of the system is reduced, and the cycle life is prolonged.

The invention discloses a current collector for a negative-electrode-free lithium metal battery and a preparation method and application of the current collector, the current collector comprises a current collector base material and a porous carbon material arranged on the surface of the current collector base material, the porous carbon material is obtained by carbonizing a porous polymer, and the porous polymer comprises a cross-linked polymer and an organic iron compound. The porous polymer containing the organic iron compound is carbonized to form the porous carbon material, the porous carbon material has high conductivity, in the carbonization process, the organic iron compound is converted into iron carbide and distributed in the porous carbon material, the porous carbon material serves as a current collector modification layer, and the conductivity of the current collector is improved. During deposition, lithium ions are induced by iron carbide and can penetrate through holes to be deposited in the carbon material instead of being deposited on the surface, so that lithium dendrites can be reduced. Moreover, the porous carbon material disclosed by the invention has relatively low thickness sensitivity, uniform deposition of lithium ions can be realized in liquid and solid battery systems, formation of lithium dendrites is reduced, and the safety of the negative-electrode-free lithium battery is improved.

The invention relates to a lithium ion battery repairing technology, in particular to an electrochemical regeneration method after capacity fading of a lithium iron phosphate battery (LiFePO). In order to overcome the defects in the prior art, the invention provides a disassembly-free and zero-cost lossless in-situ repair method based on deep pulse discharge. Aiming at the defects of complex disassembly operation, low repair efficiency and uncontrollable growth of lithium dendrites in the existing lithium ion battery repair technology, the method dynamically adjusts the lithium ion concentration gradient in a pulse intermittent period by applying a specific pulse technology and utilizing a pulse discharge-relaxation coordinated regulation mechanism, inhibits dendritic crystal growth caused by local lithium deposition, and improves the repair efficiency of the lithium ion battery. Dead lithium activation is realized, and the lithium ion battery is effectively repaired.

The invention relates to the field of new energy batteries, in particular to an electrolyte and a cathode-free lithium metal battery. The electrolyte comprises a first additive and a second additive; wherein the first additive is a fluorine-containing heterogeneous metal salt, and a metal element contained in the fluorine-containing heterogeneous metal salt is selected from at least one of Ag, Mg, Zn, Al, Au, In, Sn, Sb, Ge and Bi; the second additive is ionic liquid, and the reduction potential of cations contained in the ionic liquid is smaller than or equal to-3.04 V vs. SHE. The cathode-free lithium metal battery prepared by adopting the electrolyte provided by the invention can obviously reduce overpotential of lithium deposition, effectively induce uniform deposition of lithium and inhibit formation of lithium dendrites, and shows relatively high coulombic efficiency.

This invention provides a functional lithium metal anode, its preparation method, and a solid-state battery. The lithium metal composite anode of this invention has a three-layer structure, comprising: a current collector, an active material layer, and a functional layer. The active material layer is a lithium metal and / or lithium alloy layer. The functional layer contains boron nitride nanotubes, metal-organic frameworks (MOFs), a lithium salt, and a binder. In the functional layer, the boron nitride nanotubes are nanoscale fibrous materials with high mechanical strength, providing numerous active sites, improving the ionic conductivity of the interface layer, and effectively inhibiting the growth of lithium dendrites. The MOFs material has a three-dimensional porous structure, capable of storing a large number of lithium ions and regulating lithium ion deposition. The synergistic effect of the boron nitride nanotubes loaded with MOFs material improves the compatibility of the lithium metal anode with various solid-state electrolytes, reduces the generation of side reactions, and simultaneously increases the cycle performance and lifespan of the lithium metal solid-state battery.

The invention discloses a nitro-functionalized metal organic framework-based composite solid electrolyte as well as a preparation method and application thereof, and belongs to the technical field of lithium batteries. The preparation method comprises the following steps: carrying out hydrothermal reaction on zircon salt and nitroterephthalic acid, and carrying out centrifugal washing and drying to obtain nitro-functionalized metal organic framework powder; the method comprises the following steps: carrying out ion stirring replacement on chitosan quaternary ammonium salt and lithium salt, and carrying out centrifugal washing and drying to obtain polyion liquid powder; the method comprises the following steps: dissolving nitro-functionalized metal organic framework powder and polyion liquid powder in an organic solvent to obtain a mixed solution, casting the mixed solution on a substrate, and drying to obtain an electrolyte membrane; and soaking the electrolyte membrane in the organic electrolyte, and fully absorbing to obtain the electrolyte membrane. According to the composite solid electrolyte provided by the invention, the ionic conductivity and the lithium ion transference number can be remarkably improved, the growth of lithium dendrites is inhibited, and the electrode / electrolyte interface compatibility is improved, so that the cycling stability of a lithium metal battery is improved.

The invention provides a lithium metal negative electrode protection layer, a preparation method and application thereof, and a lithium metal battery, and relates to the technical field of lithium metal batteries, the protection layer is formed on the surface of a metal lithium foil, and comprises a polymer and an inorganic substance; the polymer comprises polyvinylidene fluoride-hexafluoropropylene; the inorganic substance includes lithium phosphate. The components of the protective layer cooperate with each other, so that lithium dendrites can be physically inhibited, the first discharge specific capacity, the first coulombic efficiency and the cycle performance can be effectively improved, gas can be actively consumed, and the cycle stability and the safety performance of the lithium metal battery can be cooperatively improved from multiple dimensions; the technical problems that an existing protective layer cannot actively eliminate gas, the lithium dendrite inhibiting effect is poor, and the interface stability is poor are solved.

The application provides a battery, liquid electrolyte is used in the middle of the battery, solid electrolyte layers are used at two ends, the performance of the full solid-state battery is effectively prevented from sharply decreasing, and the performance requirement of the power battery is effectively met, the solid electrolyte is not prone to shrinkage, the positive plate and the negative plate are fixed at the solid electrolyte layers at two ends, direct contact of the positive plate and the negative plate caused by high temperature is effectively avoided, the short circuit condition is avoided, lithium is more prone to be deposited at the edge of the negative plate in the later stage of the battery cycle, the hard layer is arranged on the edge area of the diaphragm in the application, lithium dendrites are not prone to pierce the hard layer at the edge of the diaphragm, the technical problem that the deposited lithium dendrites pass through the diaphragm to reach the positive plate is avoided, and the thermal runaway is avoided.

The invention discloses a PEO-based solid electrolyte capable of adsorbing polysulfide and a preparation method of the PEO-based solid electrolyte, and relates to the technical field of sulfur lithium batteries, the preparation method comprises the following steps: 1) preparing PEO solid electrolyte slurry; and 2) preparing the solid electrolyte film. The H-Beta molecular sieve added into the electrolyte can effectively destroy a PEO crystalline region, adsorb polysulfide and improve the ionic conductivity; the bacterial cellulose skeleton provides mechanical strength and inhibits growth of lithium dendrites. The ionic conductivity of the electrolyte reaches 2.37 * 10 <-4 > Scm <-1 > at the temperature of 60 DEG C, when the electrolyte is applied to a lithium-sulfur battery, the specific capacity of about 350 mAhg <-1 > can still be kept after 400 cycles at the rate of 1C, excellent cycle stability is shown, and the shuttle effect of polysulfide is effectively inhibited.

The application discloses an asymmetric diaphragm, a preparation method and application thereof in lithium batteries, and belongs to the field of high polymer materials and electrochemistry. The asymmetric diaphragm comprises a positive electrode side material layer, a base film and a negative electrode side material layer in sequence; the base film comprises a polypropylene diaphragm or a polyethylene diaphragm; the positive electrode side material layer is composed of a positive electrode side material layer polymer and an inorganic lithium ion conductive active ceramic material; and the negative electrode side material layer is composed of a negative electrode side material layer polymer and an inorganic ceramic material. The asymmetric diaphragm prepared by the method of electrostatic spinning and electrostatic spraying can enhance the interface stability with lithium battery positive and negative electrodes, has good wettability to electrolyte, can enhance Li + transport kinetics and inhibit uncontrollable growth of lithium dendrites, thereby improving the rate performance and long cycle stability of the battery.

The invention discloses a solid electrolyte membrane, a preparation method and a solid-state battery. The solid-state electrolyte membrane comprises a first solid-state electrolyte layer, a second solid-state electrolyte layer and a third solid-state electrolyte layer which are stacked in the thickness direction; wherein the second solid electrolyte layer comprises metal particles, and a plurality of holes formed in the second solid electrolyte layer are filled with the metal particles. The metal particles are introduced into the solid-state electrolyte membrane to induce generation of lithium dendrites, so that the service life characteristic of the solid-state electrolyte membrane is improved.