210results about How to "Improve cycle stability" patented technology

The application discloses a synthesis method of a large single-crystal sodium-ion battery layered oxide positive electrode material, and comprises the following steps: (1) weighing metal oxides containing transition metal elements, transferring to a device with mixing functions, uniformly mixing, and obtaining a metal oxide mixture; (2) adding acid to the metal oxide mixture, fully mixing, and completing an acid treatment process; (3) adding alkali to the mixture after acid treatment, fully mixing; (4) transferring the mixture obtained in the step (3) to a calcining furnace, high-temperature calcining, and obtaining a layered oxide. The acid treatment process is introduced, the surface of the metal oxide forms a defect structure under the action of the acid, and the defect structure is more beneficial to the formation of strong interaction between each component of the metal oxide and between the metal oxide and sodium-containing alkali, so that a larger single-crystal layered oxide structure is finally formed, and the specific capacity, rate performance and cycle performance are excellent.

This invention relates to a boron-doped multi-element polyanionic sodium-ion battery cathode material and its preparation method, comprising the following steps: [The method involves] mixing Na₄Fe₂O₃ with... 3‑X B X (PO4) 2‑Y (SiO4) Y The stoichiometric ratio of P2O7 is determined by adding ferrous source, boric acid, sodium source, phosphorus source, and silicon source to water, followed by the addition of carbon source and mixing thoroughly to obtain a mixed slurry; wherein 0.2≤X≤0.5, 0<Y≤1; the mixed slurry is then ground to obtain a sand-milled slurry; the sand-milled slurry is dried to obtain precursor powder; under a protective atmosphere, the precursor powder is sintered at 450~550℃ to obtain boron-doped multi-element polyanion sodium-ion battery cathode material. The introduction of boron and silicon elements in this invention helps reduce raw material costs, improve the electrochemical performance of the material, especially enhancing the structural stability, rate performance, and cycle life of the cathode material, and also lowers the sintering temperature, meeting the requirements for cost reduction and efficiency improvement.

The application discloses a nitrogen-doped carbon-coated three-metal catalyst and a preparation method and application thereof, and belongs to the field of catalyst preparation and application. The method adopts sucrose, melamine and metal salt as low-cost raw materials, and forms an alkaline environment with the assistance of sodium hydroxide. In the environment, melamine is hydrolyzed into cyanuric acid, which is complexed with sucrose metal ions to form a stable supramolecular aggregate precursor containing metal, and then realizes effective encapsulation of the metal in a high-temperature pyrolysis process. The synergistic effect of the three metal elements Co, Ni and Zn significantly improves the performance of the catalyst, so that CoNiZnO@NC-600 not only exhibits high conversion rate (98.4%) and selectivity (99%) in the reaction of hydrogenation conversion of furfural to furfuryl alcohol, but also has excellent cycle stability, thereby providing a new efficient method for the hydrogenation conversion of biomass-derived compounds.

This invention belongs to the technical field of lithium-ion battery cathode materials, specifically relating to a sulfonic acid-based organic polymer, a sulfonic acid-based organic polymer / carbon nanotube composite material, its preparation method, and its application. The sulfonic acid-based organic polymer is prepared by a dehydration condensation reaction of 2,5-diaminobenzenesulfonic acid and hexaazabenzophenanthrene hexacarboxylic acid trianal. When used as a lithium-ion battery cathode material, it exhibits high specific capacity and excellent cycle stability, overcoming the solubility problem of organic cathode materials in electrolytes. When the sulfonic acid-based organic polymer is combined with carbon nanotubes and applied to lithium-ion battery cathode materials, battery performance is significantly improved, and the capacity remains stable even after long-term cycling. The synthesis methods of the sulfonic acid-based organic polymer and the sulfonic acid-based organic polymer / carbon nanotube composite material of this invention are simple, have abundant raw material sources, and good reproducibility, making them suitable for industrial production and possessing broad application prospects in the field of lithium-ion batteries.

The application provides a biomass-based composite electrode material, an electrode sheet and a hybrid supercapacitor, and belongs to the technical field of electrochemical energy storage. 3 The biomass-based composite electrode material comprises: a biomass-derived porous carbon matrix, pores with multiple pore sizes, the volume of the pores is 0.7-1.7 cm 2 / g; and nickel-cobalt layered double hydroxide nanosheets vertically anchored on the surface of the biomass-derived porous carbon matrix; the specific surface area of the composite electrode material is 900-1400 m 2 / g. The biomass-based composite electrode material of the application significantly improves the ion adsorption and charge storage capacity. In addition, the electrode material is applied in a capacitor, which effectively improves the energy density, electrode conductivity and cycle stability of the supercapacitor.

The present application relates to ternary high-nickel lithium-ion battery cathode materials and a preparation method thereof. The general expression of the cathode material is Li(Ni 1‑a‑b‑c Co a Mn b D c )O2, 0.01

The application provides a high-nickel ternary material modification method and a high-nickel positive electrode material with a nitrogen-oxygen coating layer, and relates to the field of lithium ion batteries. In the high-nickel ternary material, surface lattice oxygen is gradually replaced by nitrogen atoms in a high-temperature long-time calcination process in a nitrogen-oxygen mixed atmosphere, so that a nitrogen-oxygen layer is formed on the surface, which is beneficial to the delocalization of electrons, thereby endowing the material with excellent electronic conductivity; meanwhile, the presence of the nitrogen-oxygen layer inhibits the transformation of the surface layer structure into a rock salt phase structure, which is beneficial to realizing efficient ion transport. The formation of the nitrogen-oxygen layer on the surface of the high-nickel ternary material can simultaneously improve the electronic and ionic conduction of the surface of the high-nickel positive electrode material, inhibit the interface side reaction, relieve the volume change, and thereby improve the cycle stability of the battery.

This invention discloses a zirconium-lanthanum bulk co-doped high-nickel ternary material, its preparation method, and a battery. The zirconium-lanthanum bulk co-doped high-nickel ternary material is a ternary cathode material with bulk co-doped zirconium and lanthanum; the chemical formula of the ternary cathode material is LiNi. x Co y Mn (1‑x‑y) O2, wherein 0.8≤x≤0.9, 0≤y≤0.1; the total molar amount of zirconium and lanthanum is 1%~5% of the total molar amount of nickel, cobalt and manganese. The zirconium-lanthanum bulk co-doped high-nickel ternary material provided by the present invention enhances the mechanical strength of the ternary material through the bulk co-doping of zirconium and lanthanum, suppresses cracking and pulverization of the ternary material during charge and discharge, and improves cycle stability; at the same time, the two elements Zr and La synergistically stabilize the lattice, reduce lithium-nickel mixing, suppress irreversible phase transformation and lattice oxygen precipitation, achieve dual stability of bulk phase and interface, and improve the consistency and stability of the zirconium-lanthanum bulk co-doped high-nickel ternary material.

The present application relates to the technical field of sodium battery materials, in particular to a sodium supplement coating based on a spiral iron-carbon composite material and a preparation method thereof, a spiral polypyrrole template is synthesized by a chiral template method, Fe3C@CNS spiral carbon composite material rich in Fe3C nanocrystals and iron single-atom sites is prepared through iron loading, sulfidation and high-temperature pyrolysis, Na2C2O4@Fe3C@CNS composite material is prepared by highly dispersing sodium oxalate on the surface and in the pores of the spiral carbon composite material through a recrystallization method, finally, a slurry is prepared by mixing the Na2C2O4@Fe3C@CNS composite material with a conductive agent and a binder, and the slurry is coated on the surface of an electrode to form a functional sodium supplement coating. The sodium supplement coating based on the spiral iron-carbon composite material and the preparation method thereof solve the problems of poor interface stability and first-cycle irreversible sodium loss of existing sodium ion batteries, realize efficient sodium pre-activation and interface synergistic regulation, and improve the comprehensive performance of the battery.

The application provides a preparation method of a binder, the binder is prepared from modified polyacrylonitrile through a cross-linking reaction and post-treatment; the modified polyacrylonitrile is a hydrolysis product of polyacrylonitrile, and the cross-linking agent of the cross-linking reaction is epichlorohydrin. The application also provides corresponding binders, lithium ion battery negative electrodes, lithium ion batteries and electrochemical devices. The binder of the application can significantly improve the cycle stability and rate performance of the battery, and the effect is particularly significant for a silicon negative electrode with large volume expansion. The preparation process of the binder of the application has the advantages of simple operation and low cost, and is easy to realize industrial production.

This invention relates to the field of flue gas treatment technology, specifically to a sulfur dioxide gas absorbent, comprising the following raw materials by weight: 90-100 parts of an aqueous amine solution and 2-6 parts of additives. In this invention, the nitrogen-zinc ion-sulfur active center of the catalyst acts as a molecular key, efficiently and reversibly coordinating and activating sulfur dioxide molecules, significantly reducing the reaction energy barrier and fundamentally improving the intrinsic absorption rate. The enhancer, with its high specific surface area, provides a large interface for the reaction. Its surface sulfonic acid groups not only buffer the decrease in system pH, maintaining the optimal acid-base environment for the reaction, but also catalyze the conversion of absorption intermediates into more stable products, thereby shifting the reaction equilibrium to the right. Under the combined effect of these two factors, the catalyst accelerates the reaction towards equilibrium, while the enhancer continuously shifts the equilibrium point, resulting in a higher absorption capacity for the absorbent.

This invention belongs to the field of solid-state electrolyte technology, specifically relating to a high-pressure resistant composite polymer solid-state electrolyte, its preparation method, and its application. The solid-state electrolyte comprises: a high-pressure resistant terpolymer, a PVDF-based polymer, mullite filler, and a lithium salt; the high-pressure resistant terpolymer is prepared from a high-pressure resistant additive, a crosslinking agent, ethylene ethylene carbonate monomer, and an initiator; the high-pressure resistant additive is selected from at least one of propylene-1,3-sulfonyl lactone, cyclobutene sulfone, and 3-methyl-3-cyclobutene sulfone. The preparation method is as follows: the high-pressure resistant additive, crosslinking agent, initiator, lithium salt, and ethylene ethylene carbonate monomer are mixed to obtain a precursor solution; the PVDF-based polymer and mullite filler are stirred and mixed in a solvent, coated into a film, and vacuum dried to obtain a base film; the base film is immersed in the precursor solution, and after immersion, it is cured to obtain the high-pressure resistant composite polymer solid-state electrolyte.

This invention belongs to the field of battery materials technology, and discloses a single-crystal lithium nickel manganese oxide material, its preparation method, and a lithium-ion battery. The single-crystal lithium nickel manganese oxide material contains Li... x Ni 2‑x The percentage content of O2 is C≤1.6%, C=(I LixNi2‑xO2 / (I LixNi2‑xO2 +I LiNi0.5Mn1.5O4 ))×100%, I LixNi2‑xO2 For Li in the XRD refinement results x Ni 2‑x The diffraction peak intensity corresponding to O2, I LixNi2‑xO2 +I LiNi0.5Mn1.5O4 To add LiNi to the XRD refinement results 0.5 Mn 1.5 O4 and Li x Ni 2‑x The diffraction peak intensity of the O2 two-phase model indicates a grain size of 5–11 μm. The aforementioned single-crystal lithium nickel manganese oxide material was prepared via a lithium-deficient high-temperature sintering and lithium-replenished low-temperature sintering process. Li x Ni 2‑x Large-particle monocrystalline lithium nickel manganese oxide materials with low O2 content avoid electrolyte decomposition under high voltage, thus preventing the generation of HF and Li. x Ni 2‑x The O2 reaction can effectively improve the cycle stability of the battery. Simultaneously, the high compaction density of monocrystalline lithium nickel manganese oxide material can enhance the battery's energy density, thermal stability, mechanical properties, and durability. The method for preparing monocrystalline lithium nickel manganese oxide material in this invention is relatively simple, reliable, and effective, and can utilize existing production lines.

The application discloses a preparation method of nitrogen-doped carbon-silicon nanofibers and application of the nitrogen-doped carbon-silicon nanofibers in a lithium ion battery negative electrode material, and belongs to the technical field of lithium ion battery negative electrode materials. The method comprises the following steps: mixing silicon nanoparticles and a carbon source, performing electrostatic spinning, stabilization treatment and carbonization treatment, and obtaining carbon-silicon nanofibers; and then mixing the carbon-silicon nanofibers with a nitrogen source, performing heat treatment under an inert atmosphere, making nitrogen elements doped into a carbon skeleton, and obtaining nitrogen-doped carbon-silicon nanofibers. The material obtained by the application is a one-dimensional nanofiber structure, silicon particles are uniformly wrapped in carbon fibers, and nitrogen elements are uniformly distributed in the carbon skeleton. The method can realize uniform nitrogen doping while maintaining the microstructure of the material, and significantly improves the electronic conductivity and interface stability of the material. The material obtained by the application is used as a lithium ion battery negative electrode, and exhibits high reversible capacity and excellent cycle stability.

This invention discloses a low-temperature resistant, high-power aqueous organic-bromine battery, belonging to the field of electrochemical energy storage technology. The invention uses a low-freezing-point bromine-based salt solution with added bromine solid complexing agent as the electrolyte, and a pseudocapacitive organic material as the negative electrode, which possesses ionic universality and can bind metal ions in the solution during the reaction. The positive electrode uses a carbon material as a substrate, where a bromine redox reaction occurs. Simultaneously, the complexing agent can complex bromine in solid form onto the carbon surface, ensuring good stability at both room temperature and low temperatures. The aqueous organic-bromine battery of this invention exhibits high energy density and ultra-high power density at room temperature, maintains high energy density even at low temperatures, and is inexpensive, showing promising application prospects.

This invention provides an electropolymer-modified aluminum current collector, its preparation method, and its application, relating to the field of aluminum foil current collector technology. By modifying the current collector surface, it primarily addresses the interface problem between the current collector and the active material, thereby improving the performance of lithium-ion batteries. This invention uses an aluminum foil current collector as the anode, a graphite plate as the cathode, and an acidic solution of a conductive polymer monomer as the electrolyte. Anodizing electropolymerization is performed using a constant current or constant voltage method, followed by washing and drying to obtain the electropolymer-modified aluminum current collector. The conductive polymer monomer is at least one of aniline, thiophene, and pyrrole; the concentration of the conductive polymer monomer in the electrolyte is 0.1-1.0 mol / L; and the polymerization time is 5-10 min. This invention effectively reduces the contact resistance between the current collector and the active material, improves the bonding strength between the coating and the substrate, and enhances the corrosion resistance of the current collector, showing promising application prospects.

This application discloses a negative electrode and its related manufacturing method and product, belonging to the field of zinc-ion batteries. The negative electrode includes: a metal current collector; and an adhesion layer attached to the surface of the metal current collector through a chemical reaction; wherein the adhesion layer is composed of at least two metal elements. This negative electrode can effectively suppress dendrite growth and side reactions such as hydrogen evolution, thereby improving the cycle stability of the battery.

This invention discloses a sucrose-polypropylene composite hard carbon and its preparation method, belonging to the technical field of sodium-ion battery anode materials. The preparation method of the composite hard carbon includes using sucrose as a raw material, first preparing a precursor, mixing it with polypropylene, ball milling it, pre-oxidizing it at low temperature, and then carbonizing it at high temperature. The closed-pore volume of the material of this invention increases, the interlayer spacing expands, and the packing density of the material increases, thereby improving the energy density of the material. The reversible specific capacity of the hard carbon material of this invention can be increased from the initial 271 mAh g. ‑1 Increased to 387mAh.g ‑1 The capacity ratio in the low-voltage plateau region can be increased from 54% to 64%. Under optimal process conditions (M-SC:PP = 2:1, pre-oxidation at 330℃), the sucrose-polypropylene composite hard carbon prepared at 100 mA g... ‑1 It still retains 240mAh after 300 cycles. ‑1 Its capacity is far higher than that of directly calcined sucrose-based hard carbon materials (100 mAh / g). ‑1 The material exhibits good cycle stability and rate performance.

This invention discloses a method for preparing a graphene / silicon-carbon composite anode material. The method includes: firstly, preparing a carbon-coated silicon dioxide precursor via a hydrothermal reaction; then, converting it into a carbon-coated silicon material using a magnesothermic reduction method in the presence of sodium chloride, effectively inhibiting the aggregation and growth of silicon particles; finally, combining graphene with the carbon-coated silicon material through a secondary hydrothermal and calcination treatment to construct a conductive network. This invention, through a multi-level structural design, utilizes the synergistic buffering effect of the internal carbon layer and the external graphene to effectively alleviate the volume expansion of silicon during charging and discharging, significantly improving the conductivity and structural stability of the material. The prepared composite anode material exhibits high specific capacity and excellent cycle performance, making it suitable for lithium-ion battery applications.

This invention discloses a method for preparing cobalt-manganese sulfide nanosheets@cobalt-copper sulfide nanowire arrays / nickel foam as a supercapacitor electrode material. The purpose of this invention is to design a core-shell structure composed of different components to improve the specific capacity and cycle performance of the electrode material. This invention mainly includes: 1. Hydrothermal preparation of cobalt-copper precursor / nickel foam (CoCu-pre / NF); 2. Hydrothermal sulfidation preparation of cobalt-copper sulfide nanosheet arrays / nickel foam (CuCo2S4 / NF); 3. Hydrothermal preparation of cobalt-manganese sulfide nanosheets@cobalt-copper sulfide nanowire arrays / nickel foam (MnCoS@CuCo2S4 / NF). This invention features a simple synthesis process, low cost, high yield, and no need for subsequent processing. The MnCoS@CuCo2S4 heterostructure exhibits stronger OH... ‑ The MnCoS@CuCo2S4 / NF electrode exhibits high capture capacity and excellent conductivity, thereby enhancing the efficiency of rapid redox processes. At 1 A g... ‑1 At that time, it obtained 1141.2 C g. ‑1 The specific capacitance at 10 A g ‑1 It exhibits excellent cycling performance of 90.7% over 10,000 cycles. (740.47 W kg) ‑1 At a power density of 64.38 Wh / kg, the hybrid supercapacitor (HSC) can provide 64.38 Wh / kg. ‑1 The electrode exhibits high energy density and can successfully light up LED bulbs. It has enormous application potential as a high-performance electrode material for supercapacitors.

This invention provides an in-situ solid-state battery and its preparation method, comprising a battery cell and an in-situ solidified electrolyte precursor injected into the battery cell. The in-situ solidified electrolyte precursor is formulated according to the following mass percentages: 1-30 wt.% polymeric monomer, 0.1-1 wt.% initiator, 10-20 wt.% lithium salt, 0.1-10 wt.% redox shuttle, and the balance being an organic solvent. This invention utilizes the redox shuttle to react within the battery, converting electrical energy into heat, thereby uniformly heating the battery interior and solidifying the gel electrolyte in situ. This method provides more uniform heating and a more uniform polymerization effect, resulting in a more uniform and stable battery interface and higher cycle stability, thus producing a high-performance solid-state battery. Furthermore, this method is applicable to most polymeric monomers and achieves uniform heating within the battery without adding additional equipment.

The application discloses a manganese iron lithium phosphate composite positive electrode material with Mn ion self-compensation and multiple interception functions and a preparation method thereof. The manganese iron lithium phosphate composite positive electrode material is composed of a manganese iron lithium phosphate positive electrode material and functional composite film micro-powder loaded on the surface and between the particles of the manganese iron lithium phosphate positive electrode material. The functional composite film of the functional composite film micro-powder is prepared from Na-merolite powder through Mn ion exchange, grafting and copolymerization, lithiumation and PVA composite film preparation. The manganese iron lithium phosphate composite positive electrode material is prepared from the manganese iron lithium phosphate positive electrode material and the functional composite film through mixing, crushing and freeze-drying. The manganese iron lithium phosphate composite positive electrode material realizes the inhibition of the dissolution of Mn 2+ in the manganese iron lithium phosphate positive electrode material from the source, improves the ion conduction performance and the cycle stability of the manganese iron lithium phosphate positive electrode material, and has the advantages of high capacity, long cycle life, high safety and the like.

The application discloses a kind of quasi-solid electrolyte and preparation method thereof, battery, electrical device, electrolyte salt is mixed with carbonate solvent, and preparation base electrolyte solution;Diluent and initiator are added to base electrolyte solution and are reacted, and quasi-solid electrolyte is prepared;The diluent includes ring-opening polymerizable cyclic monomer diluent, and the mass ratio of the diluent, the initiator and the base electrolyte solution is (30-70) : (0.1-0.5) : (30-70) in turn.The precursor solution containing local high concentration solvation structure is formed in the preparation process of quasi-solid electrolyte of the application, and quasi-solid electrolyte with low impedance, high ionic conductivity, excellent high rate performance and good safety performance is prepared using in-situ polymerization technology.The quasi-solid electrolyte prepared by the application is assembled into battery, with excellent charge-discharge performance, excellent cycle stability under high rate conditions, and low economic cost and high practicality.

This application discloses a separator and a battery cell, relating to the field of secondary battery technology. The separator disclosed in this application includes a base layer and a coating layer located on at least one side of the base layer. The coating layer is made of a polymer, which includes primary particles and secondary particles. Before the separator comes into contact with the electrolyte, the average particle size of the primary polymer particles is A μm, and the average particle size of the secondary polymer particles is B μm. After the separator is wetted with the electrolyte, the average particle size of the primary polymer particles is C μm, and the average particle size of the secondary polymer particles is D μm. Furthermore, A, B, C, and D satisfy the following condition: 5% < (D-B) / B < (C-A) / A < 50%. The separator described in this application exhibits good electrolyte resistance and good adhesion to the electrodes.

The application discloses a high-transmission wide-temperature-range sodium ion battery anode based on a two-phase layered oxide and a preparation method and application thereof, and belongs to the technical field of sodium ion batteries. The sodium ion battery anode comprises an anode active material, a conductive agent and a binder, wherein the anode active material comprises a layered oxide component and a complex component; the layered oxide component comprises O3-phase NaNi 0.2 Fe 0.2 Co 0.2 Mn 0.2 Ti 0.2 O2 and P2-phase Na 0.67 Ni 0.33 Mn 0.37 Ti 0.3 O2, the complex component comprises Na2MnPO4F, Na2FePO4F and Na2FeSiO4, the conductive agent is a mixture of super conductive carbon black (SP) and carbon nanotubes (CNT), and the binder is polyvinylidene fluoride (PVDF). The O3 / P2 two-phase layered oxide provides high capacity and structural stability, the polyanion compound material guarantees ion transmission and thermal stability, and the conductive agent optimizes electron transmission. The prepared sodium ion battery has the effects of breaking through the low-temperature performance limitation, significantly improving the sodium ion transmission efficiency, cycle stability and excellent safety and stability.

The application discloses a battery and a manufacturing method thereof, and the battery comprises a positive current collector layer, which is a composite structure with dense normal layers and porous functional layers alternately distributed formed on an aluminum foil substrate through electric field assisted selective etching, a positive electrode sheet coated with positive active material aluminum powder and subjected to formation treatment, and a top cover assembly and a bottom cover assembly connected with the positive and negative electrodes through full-tab cross-section laser welding and full-tab end face laser welding respectively; the manufacturing method comprises the steps of preparing a composite positive current collector layer, coating active material, assembling a battery cell, laser welding and packaging, etc. The specific surface area and ion transmission efficiency are greatly improved through the composite current collector layer structure, the internal resistance and temperature rise are reduced by combining the optimized full-tab welding process, so that the rate performance, cycle stability and thermal safety of the battery are significantly improved, and the battery is suitable for the manufacturing of high-power long-life batteries such as electric vehicles and energy storage systems.

The application discloses a gradient electron regulation type noble metal-transition metal bifunctional catalyst and a preparation method and application thereof, and comprises active metal components A, auxiliary active metal components B, oxide carriers C and surface electron regulation components D. In the application, the noble metal is enriched on the outer layer of the carrier, directly participates in the surface catalytic reaction, the catalytic efficiency of unit mass noble metal is significantly improved, and excellent hydrogenation and dehydrogenation performance can be realized. The inner layer transition metal promotes hydrogen overflow and hydrogenation activity, the outer layer noble metal provides efficient dehydrogenation sites, and the two realize ordered division and cooperation in space through the gradient distribution structure, thereby solving the problem of disordered distribution of traditional two metals and insufficient cooperation effect. The gradient distribution structure reduces the migration and agglomeration tendency of metal particles in high-temperature circulation, the oxygen vacancies and basic sites of the oxide carrier inhibit carbon deposition, and the catalyst can maintain high activity and stability in multiple hydrogenation-dehydrogenation cycles, and the cycle life is significantly better than that of a conventional co-impregnated bimetallic catalyst.

The application discloses a silicon-carbon negative electrode material, a preparation method and a battery, and relates to the technical field of battery materials. The preparation method comprises the following steps: placing a porous carbon material in an inert atmosphere, pre-treating by heating, and removing impurities and moisture on the surface of the material; depositing a nano-silicon layer on the surface of the pre-treated porous carbon material in a gas phase; then depositing a carbon coating layer on the surface of the nano-silicon layer; and performing oxidation passivation treatment on the surface of the carbon coating layer, thereby obtaining the silicon-carbon negative electrode material.

This application relates to the technical field of lithium-ion battery materials, specifically disclosing a high-efficiency silicon-oxygen composite anode material, its preparation method, and its application. The preparation method of this anode material includes the following steps: mixing a siloxane with a fatty acid at a mass ratio of 1:(5~35), and ball milling under inert gas protection to obtain a pre-coated mixture; heating the pre-coated mixture to 50~1500℃ under an inert atmosphere and holding for 1~20h to obtain a carbon-coated silicon-oxygen material; immersing the carbon-coated silicon-oxygen material in a lithium-rich organic composite solution, holding at -5~25℃ under inert gas protection for 5~180 minutes, and drying to obtain a pre-lithiation product; mixing the pre-lithiation product with a nitride at a mass ratio of 1:(0.1~5), and ball milling under inert gas protection to obtain the high-efficiency silicon-oxygen composite anode material. This application can synergistically improve the stability and initial efficiency of the silicon-oxygen composite anode material.

The application discloses a preparation method of a single-crystal metal lithium negative electrode. The single-crystal metal lithium negative electrode with a dense packing surface Li(110) is obtained by annealing a polycrystal metal lithium foil horizontally placed after being heated in vacuum or inert atmosphere, and is directly used for battery assembly. The application remarkably improves the electrode reaction process kinetics of the metal lithium negative electrode by reducing the self-diffusion barrier of the surface of the metal lithium negative electrode, widens the safety boundary of the metal lithium negative electrode, and enables the metal lithium negative electrode to have no dendrite growth in a practical current density range. The prepared single-crystal metal lithium negative electrode can be directly used for battery assembly, and remarkably improves the cycle stability and safety of a high-specific-energy metal lithium battery, and promotes the development of practical high-safety metal lithium batteries.