1574 results about "Lithium ion battery anode" patented technology

The invention provides a lithium ion battery silicon-based negative electrode material as well as a preparation method and application thereof, and relates to the technical field of lithium ion battery negative electrode materials. The preparation method provided by the invention comprises the following steps: stirring and mixing a surface-activated silicon-carbon matrix in an organic solution in which a polymer is dissolved, separating and drying to obtain a composite matrix; mixing the composite matrix in an inorganic lithium salt solution, evaporating the solvent to dryness, and carbonizing at 300-400 DEG C to obtain a composite intermediate; reducing the composite intermediate in a hydrogen atmosphere at 200-300 DEG C to obtain a negative electrode intermediate; and stirring and mixing the negative electrode intermediate in the organic solution, separating and drying, and carbonizing at 700-800 DEG C to obtain the silicon-based negative electrode material of the lithium ion battery. The prepared negative electrode material has relatively high structural stability, and after the negative electrode material is applied to the lithium ion battery, the capacity performance and the cycling stability of the lithium ion battery can be remarkably improved.

The invention belongs to the technical field of lithium ion battery negative electrode materials, and particularly relates to a method for preparing a lithium ion battery negative electrode material from sulfur-doped black phosphorus-carbon. A carbon material and sulfur powder are subjected to ball milling, uniform mixing and vacuum high-temperature calcination to obtain a sulfur-doped carbon material; and uniformly mixing the sulfur-doped carbon material with black phosphorus, and performing high-energy ball milling in an inert atmosphere to obtain the sulfur-doped black phosphorus-carbon composite negative electrode material. According to the preparation method provided by the invention, the black phosphorus, the carbon material and the sulfur are well combined, so that the high capacity of the material is ensured, the structural stability of the composite material can be improved, the polarization of the material is reduced, and the cycling stability and the rate capability of the battery are improved.

The invention discloses a preparation method of a silicon-carbon material for a negative electrode of a lithium ion battery, and relates to the technical field of lithium ion batteries, and the preparation method comprises the following steps: (1) selecting a specific silicon source solute and an organic solvent to prepare an organic silicon source solution; (2) selecting porous carbon as a substrate, and carrying out vacuum impregnation treatment in a silicon source solution; (3) carrying out solvothermal silicon deposition reaction on the porous carbon impregnated with the silicon source solution in a high-pressure reaction kettle; (4) carrying out vacuum impregnation on the deposited silicon porous carbon subjected to solvent heat treatment in a carbon source organic solvent; and (5) cracking and carbonizing the deposited silicon porous carbon impregnated with the carbon source solvent at a high temperature to form the composite silicon carbon material with carbon-coated silicon crystal particles. According to the present invention, the energy density of the lithium ion battery negative electrode material is improved while the cycle life and the rate capability are significantly improved, such that the prepared silicon-carbon material has excellent electrochemical performance, and can well meet the application requirements of the lithium ion battery on the aspects of high energy density, long cycle life, high-rate charge-discharge and the like.

The invention belongs to the technical field of energy storage materials, and particularly relates to a high-entropy oxide Fe0. 2Co0. 2Ni0. 2Cu0. 2Zn0. 2O and an ultrafast synthesis method and application thereof. According to the preparation method, ferroferric oxide, cobalt oxide, nickel oxide, copper oxide and zinc oxide with equal molar ratio are adopted as direct synthesis raw materials, toxic gases such as chlorine and nitrogen dioxide generated in the synthesis process of a metal salt precursor are avoided, and the uniformly distributed single-phase high-entropy oxide is synthesized in an ultrafast manner within 10 seconds by using a Joule heating technology; the synthesized high-entropy oxide is used as a lithium ion battery negative electrode material, and shows more excellent electrochemical performance and cycling stability compared with other high-entropy oxides prepared from transition metals with different proportions; in the preparation process, extra additives are not needed, operation is easy, the synthesis speed is high, the yield is high, element distribution is uniform, and the method has the advantages of being low in cost, high in efficiency and free of pollution and has the industrialization prospect.

Provided in the present invention are a polyacrylic acid or polyacrylate water-based binder, and a preparation method therefor and the use thereof. The polyacrylic acid or polyacrylate water-based binder is a polymer obtained by polymerizing polymeric monomers, the polymeric monomers comprising a hard monomer, a soft monomer and a functional monomer. The polyacrylic acid or polyacrylate water-based binder provided by the present invention has relatively high binding power and relatively good flexibility and electrochemical stability, and has good application prospects in the field of negative electrode sheets of lithium-ion batteries.

The invention provides a superfine nano silicon-based negative electrode material prepared based on in-situ high-temperature phase change in a specific confinement microcavity and a preparation method of the superfine nano silicon-based negative electrode material. The method comprises the following steps: mixing silicon and a conductive porous material in a solvent, sanding, forming solid particles through reforming granulation, and constructing a confinement microcavity through coating treatment. And the silicon source is sublimated and desublimated into particles with the particle size of less than 10nm through transient heating and cooling, and the particles are embedded into the porous material, so that the extreme nanocrystallization of silicon is realized. The method effectively solves the problems of volume expansion, low conductivity, poor cycle stability and the like when silicon is used as a lithium ion battery negative electrode material, improves the electron transmission and cycle life, simplifies the process, reduces the cost, and has a good commercialization prospect.

The present application relates to the technical field of lithium battery materials and binders, and discloses an aqueous polymeric binder, a preparation method therefor and a use thereof. The aqueous polymeric binder is obtained by copolymerizing a polymerization unit comprising an acrylic monomer, an acrylate monomer, an oil-soluble monomer, a water-soluble monomer, and an amphiphilic water-soluble monomer in an aqueous solvent; and the mass percentages of the monomers are as follows: acrylic monomer: 5%-15%; acrylate monomer: 45%-60%; oil-soluble monomer: 10%-40%; water-soluble monomer: 5%-20%; and amphiphilic water-soluble monomer: 5%-10%. The aqueous polymeric binder of the present application is mainly used for bonding of an edge coating of a negative electrode sheet of a lithium-ion battery; on the basis of the specific copolymerization monomer components and proportions, the obtained binder has excellent PP base film bonding performance and electrolyte swelling resistance; in addition, the binder avoids material mixing with a negative electrode, and has good prospects of application.

The invention discloses a porous carbon material applied to a silicon-carbon negative electrode as well as a preparation method and application of the porous carbon material, and belongs to the technical field of lithium ion batteries. Uniformly mixing asphalt and mixed acid, heating and fully reacting to obtain acid modified asphalt; dispersing the acid modified asphalt in deionized water to prepare an asphalt aqueous solution, sequentially adding melamine and KOH, uniformly dispersing to obtain a mixed solution, and drying to obtain precursor powder; carbonizing the precursor powder under the protection of nitrogen, and then introducing CO2 or water vapor or mixed gas of the CO2 and the water vapor for activation; and washing and drying the activated product to obtain the porous carbon material. The obtained material has excellent conductivity, stability and high silicon loading performance, and can be applied to the field of lithium ion battery negative electrode materials, a silicon-carbon negative electrode prepared by taking the porous carbon material as a carrier is applied to a lithium ion battery, and the technical effects of high capacity density and long circulation can be achieved.

The invention relates to the technical field of lithium ion batteries, and provides a negative plate and a lithium ion battery. The negative plate comprises a negative current collector and a negative active material layer arranged on at least one side surface of the negative current collector; the negative electrode active material layer comprises a first negative electrode active material layer and a second negative electrode active material layer, and the second negative electrode active material layer is arranged between the negative electrode current collector and the first negative electrode active material layer; the first negative electrode active material layer comprises an amorphous carbon coated graphite material, and the second negative electrode active material layer comprises a graphite material; the Dv50 of the amorphous carbon coated graphite material is recorded as P1 [mu] m, the Dv50 of the graphite material is recorded as P2 [mu] m, and P1 and P2 satisfy: P1gt; p2. The negative plate adopts a double-layer coating design to form the negative plate of which the surface layer has quick charge and the bottom layer has high energy density, so that the negative plate has both high energy density and quick charge performance.

The invention relates to the field of batteries, in particular to a preparation method and system of a silicon-carbon material, and the preparation method comprises the following steps: pretreating porous carbon, conveying the pretreated porous carbon to a fluidized bed reactor, sequentially introducing a silicon source gas and a carrier gas for silicon deposition treatment, heating, introducing a carbon source gas, adjusting the flow of the carrier gas for carbon coating treatment, and discharging and cooling to obtain a finished product, meanwhile, reaction tail gas is recycled. The preparation system comprises a gas inlet unit, a fluidized bed reactor unit, a tail gas circulation unit, a feeding preheating unit and a discharging unit. The fluidized bed reactor comprises an outer shell, an up-down stirring device, a heat exchange assembly and an air distribution assembly, and efficient reaction and temperature control can be achieved. The silicon-carbon material prepared by the method has excellent electrochemical performance and is suitable for a lithium ion battery negative electrode material. The unique porous structure and the uniform carbon coating layer effectively improve the conductivity and the structural stability of the material, and meanwhile, the volume expansion effect of silicon in the charging and discharging process is reduced.

The invention relates to the technical field of lithium ion battery negative electrode materials, in particular to a graphite composite material and a preparation method and application thereof. The preparation method comprises the following steps: heating metal lithium to obtain lithium steam, and depositing the lithium steam into a metal organic framework material to obtain a lithium-doped metal organic framework material; a chemical vapor deposition method is adopted, carbon source gas and oxygen are introduced, amorphous carbon is deposited in the lithium-doped metal organic framework material, and an amorphous carbon and lithium co-doped metal organic framework material is obtained; and mixing the amorphous carbon and lithium co-doped metal organic framework material, a metal salt solution and a graphite material to obtain a mixture, heating, carrying out solid-liquid separation, taking solid components, introducing carbon source gas, and reacting to generate carbon nanotubes, thereby obtaining the graphite composite material. When the prepared graphite composite material is applied to a lithium ion battery as a negative electrode material, the battery has the advantages of high first efficiency, good liquid retention performance, low expansion, fast charge, good cycle performance and the like.

The invention provides an amorphous copper nanolayer coated spherical porous silicon composite material and a preparation method and application thereof.The preparation method includes the step that the surface of spherical porous silicon is coated with an amorphous copper conductive nanolayer through a simple solution method.On the basis of the principle of replacement reaction, aluminum in aluminum-silicon alloy is replaced with copper to be coated on the surface of silicon, and the amorphous copper nanolayer coated spherical porous silicon composite material is obtained. And meanwhile, the rate of the replacement reaction is slowed down by utilizing different reaction activities of copper chloride in an organic solvent, so that the spherical morphology is kept, and meanwhile, the surface of silicon can be coated with a layer of amorphous copper nano layer with high conductivity. The invention also provides a preparation method of the material. Tests find that the conductivity of the material can be effectively improved due to the excellent conductivity of the copper nano layer, and the volume expansion effect of the material in the electrochemical cycle process can be effectively relieved due to the porous structure. Therefore, the combination of the two effectively improves the problems of poor conductivity and unstable structure of the silicon negative electrode material, and effectively improves the application performance of the silicon negative electrode material in the lithium ion battery negative electrode.

The invention relates to a silicon-carbon composite material with a porous structure and a preparation method thereof, and the silicon-carbon composite material with the porous structure comprises an N / P co-doped porous carbon skeleton with micropore, mesopore and macropore channel networks, and amorphous or low-crystalline nanometer silicon particles which are uniformly loaded in the porous carbon skeleton and have the average particle size of 15-40nm, the mass percent of silicon in the composite material is 40-60%, and good interface bonding is formed between silicon and carbon. The preparation method mainly comprises the following steps: firstly, preparing an N / P co-doped porous carbon skeleton through a template method in combination with high-temperature carbonization and N / P source co-pyrolysis; and hydrolyzing an organic silicon source in the carbon skeleton to form silicon dioxide, and performing low-temperature metal thermal in-situ reduction to obtain the nano-silicon loaded composite material. Through a unique porous carbon skeleton design and a precise in-situ composite strategy of nano silicon, the prepared material shows high specific capacity, high initial coulombic efficiency and excellent cycling stability and rate capability when being used as a negative electrode of a lithium ion battery.

The invention relates to a negative pole piece, a winding battery cell and a lithium ion battery. The negative pole piece comprises a first active coating coated on one side of a negative current collector and a second active coating coated on the other side of the negative current collector, the first active coating is an active coating coated by the positive pole piece when the negative pole piece is wound, and the surface density of the first active coating is greater than that of the second active coating; the first active coating and the second active coating comprise an inner side active coating close to the negative electrode current collector and an outer side active coating coated on the surface of the inner side active coating; the outer active coating comprises a first negative electrode active material, the inner active coating comprises a second negative electrode active material, and the second negative electrode active material comprises a silicon-carbon negative electrode material and the first negative electrode active material; and the surface density of the outer active coating is smaller than that of the inner active coating. According to the scheme provided by the invention, the lithium precipitation phenomenon in the arc region of the negative electrode plate of the lithium ion battery can be effectively prevented, and the cycle performance of the lithium ion battery is improved.

The invention discloses negative electrode slurry and a preparation method thereof, a negative electrode plate and a lithium ion battery, the negative electrode slurry comprises a negative electrode material, the negative electrode material comprises a negative electrode active substance with the mass content of 85%-98% and a surface tension regulator with the mass content of 0.1%-5%, the surface tension regulator is at least two of isopropanol, propylene glycol and allyl alcohol. According to the invention, the problem of vertical lines and even cracking during coating of the pole piece can be improved, the cycle performance and the safety performance of the battery are ensured, and meanwhile, environmental pollution is avoided.

The invention discloses a silicon-carbon negative electrode material, a preparation method thereof and a lithium ion battery, and relates to the technical field of lithium ion battery negative electrode materials. The material sequentially comprises a porous silicon core, a transition layer and a shell from inside to outside, the transition layer is a nitrogen-doped SiC / C composite layer, the shell comprises a graphene / carbon nanotube skeleton and MXene quantum dots, the MXene quantum dots are embedded in the graphene / carbon nanotube skeleton, boric acid ester bonds exist between carbon nanotubes and graphene, and the MXene quantum dots are embedded in the graphene / carbon nanotube skeleton. The silicon-carbon negative electrode material is based on dual-network dynamic bonding and stress gradient regulation and control, the cycle performance of the material can be remarkably improved, and the service life of the material can be remarkably prolonged.

The invention discloses a lithium ion battery negative pole piece, a preparation method thereof and a lithium ion battery, and belongs to the technical field of lithium ion battery electrode materials. The lithium ion battery negative electrode plate provided by the invention comprises a negative electrode current collector; the graphite layers are arranged on the surfaces of the two sides of the negative electrode current collector; the graphite layer comprises graphite particles, a conductive agent and a binder; the hard carbon layer is arranged on the surface of one side, far away from the negative electrode current collector, of the graphite layer; the hard carbon layer comprises hard carbon particles, a conductive agent and a binder; wherein the graphite layer and the hard carbon layer meet the relational expression: 1.4 < = rho1 * D1 + rho2 * D2 + PD < = 1.75. According to the invention, through proper design of the composite layer structure, the surface density, the compaction density and the particle sizes of the graphite particles and the hard carbon particles, the rapid charging performance of the lithium ion battery is improved, and meanwhile, relatively high energy density is kept; and the negative pole piece also has relatively good flexibility, so that the problems of breakage and powder falling in the processing process are relieved.

The invention relates to the technical field of lithium ion battery negative electrode materials, in particular to a nitrogen-doped carbon metal oxide composite material and a preparation method thereof, a negative electrode material, a negative electrode plate and a lithium ion battery. The nitrogen-doped carbon metal oxide composite material comprises Co2NiO4 with a hollow cubic structure, and a nitrogen element and a carbon element which are dispersed on the surface of the Co2NiO4. The material is good in conductivity, low in resistance and good in structural stability, volume expansion caused by Li < + > embedding in the circulation process can be relieved, the volume expansion effect in the material charging and discharging process can be inhibited, the electrode polarization effect can be reduced, and the charging and discharging specific capacity, the rate capability and the circulation stability of the material can be effectively improved.

The negative electrode active material layer of the negative electrode of a lithium-ion battery comprises negative electrode active substances (2) and lithium-carbon materials (3) of a silkworm cocoon structure, the lithium-carbon materials (3) of a silkworm cocoon structure being distributed between the negative electrode active substances (2). The lithium-carbon materials (3) of a silkworm cocoon structure each comprise a cocoon body formed of a structural carbon material and one or more lithium-containing particles contained in the cocoon body. The negative electrode of the lithium-ion battery has a stable structure and a controllable pre-lithiation degree, and is used in conjunction with a conventional positive electrode, thereby significantly improving the initial coulombic efficiency and cycle life of the lithium-ion battery. The preparation method for the negative electrode of the lithium-ion battery is simple, and can implement large-scale industrial production.

The invention discloses a lithium ion battery negative electrode with low expansion and low impedance. The lithium ion battery negative electrode comprises a composite current collector and a negative electrode active material coating coated on at least one surface of the composite current collector, the negative electrode active material coating comprises a negative electrode active material, graphene and lithium polyacrylate; the mass ratio of the negative electrode active material to the graphene to the lithium polyacrylate is (90-99): (0.5-5): (0.5-5), the negative electrode active material comprises a silicon carbon material and a coating material layer arranged on the outer surface of the silicon carbon material, and the coating material layer comprises a polypyrrole layer and single-walled carbon nanotubes uniformly distributed in the polypyrrole layer. Compared with the prior art, the lithium ion battery negative electrode provided by the invention has the advantages of low expansion and low impedance, and can effectively inhibit the expansion of silicon particles, reduce the internal resistance of the battery and maintain the structural stability of the electrode.

The invention relates to the technical field of lithium ion battery negative electrode materials, in particular to a silicon-carbon negative electrode material, a preparation method thereof and an electrochemical device. The silicon-carbon negative electrode material comprises nano silicon slurry and organic carbon, and the mass ratio of a silicon material to the organic carbon is (1: 0.1)-(1: 2); the nano silicon slurry is prepared by wet grinding and comprises micron silicon powder, dispersion liquid, a dispersing agent, an antioxidant and an ammonia-containing conditioning agent, and the mass ratio of the micron silicon powder to the dispersion liquid to the dispersing agent to the antioxidant to the ammonia-containing conditioning agent is (1-4): (10-20): (0-1): (0-1): (0-1). According to the nanometer silicon grinding formula and the preparation method of the silicon-carbon negative electrode material provided by the invention, the ammonia-containing tempering agent is added in the physical grinding process, so that the dispersity of nanometer silicon in the slurry is improved, the grinding efficiency is improved, the particle size of the nanometer silicon is reduced, the grinding energy consumption can be remarkably saved, the production cost is reduced, and commercialization is promoted.

The invention belongs to the technical field of lithium ion battery materials, and discloses a perovskite type titanate material as well as a preparation method and application thereof, the structural formula of the perovskite type titanate material is AxByTiOz, an A-site element is an alkali metal element, a B-site element is a Y element and / or a lanthanide element, 0 < x < = 1, 0 < y < = 1, and x + 3y + 4 = 2z. The perovskite type titanate material meeting the chemical general formula of AxByTiOz is designed, the obtained perovskite type titanate material AxByTiOz can be used as a lithium ion battery negative electrode material, compared with a lithium titanate negative electrode, the perovskite type titanate material AxByTiOz has high energy density brought by more ideal working potential, meanwhile, compared with a graphite carbon material, the perovskite type titanate material AxByTiOz has high lithium intercalation state thermal stability, and the performance of the perovskite type titanate material AxByTiOz is improved. And high safety and high energy density of the lithium ion battery can be considered at the same time.

The invention provides a silicon carbon material with a multilayer coating structure and a preparation method and application thereof, and relates to the technical field of battery materials. The silicon-carbon material with the multi-layer coating structure comprises a porous carbon core body, and a first carbon layer and a second carbon layer which sequentially coat the porous carbon core body from inside to outside, and the porous carbon core body comprises porous carbon and nano silicon particles deposited on the surface and in pore channels of the porous carbon; and a conductive nano carbon filler is dispersed in the second carbon layer. The silicon carbon material with the multilayer coating structure provided by the invention is used as a lithium ion battery negative electrode material, and has excellent specific capacity, coulombic efficiency and cycle performance. The result of the embodiment shows that when the silicon carbon material with the multi-layer coating structure is applied to the lithium ion battery, the first reversible capacity is 1882-2071 mAh / g, the first coulombic efficiency is 92.6-94.1%, and the capacity retention ratio of 100 cycles is 95.3-97.7%.

The invention relates to the technical field of lithium ion battery negative electrode materials, and discloses a preparation method and application of a high-efficiency silicon-carbon composite graphite material, and the preparation method comprises the following steps: S1, carrying out porosity and size regulation and control on silicon particles: carrying out ball milling on industrial-grade silicon powder to obtain nano silicon particles, and carrying out acid etching to form a porous structure; s2, functional surface treatment and interface optimization: introducing functional molecules to the surfaces of the silicon particles and coating a layer of ultrathin SiO2 protective film; and S3, carbon coating and flexible protection layer construction: performing pyrolysis on the porous silicon particles by using a carbon source to form a uniform carbon coating layer which is applied to a lithium ion battery negative electrode material, and the lithium ion battery is used for an electric vehicle, a power grid energy storage system and portable electronic equipment. Through the collaborative design of the flexible protection layer, the double-layer carbon coating and the gradient coating, the technical bottlenecks of the silicon-based negative electrode material in the aspects of long cycle stability, high rate performance and interface chemical stability are systematically solved.

The invention belongs to the technical field of lithium ion battery negative electrode materials, and particularly relates to a spinel type metal oxide coated hard carbon composite material based on a lattice matching mechanism, and a gradient doping preparation method of the spinel type metal oxide coated hard carbon composite material can overcome the defects that a hard carbon material is low in initial coulombic efficiency (about 50%), low in lithium ion transmission rate and poor in rate capability. According to the invention, magnesium salt, aluminum salt, copper salt and other metal salts are mixed with hard carbon, a precipitant is added, and a hydrothermal method is combined with a calcination process to obtain the core-shell structure composite material with hard carbon coated with a spinel structure. The technology has the following three obvious advantages: (1) lattice adaptive design of the spar type metal oxide and the hard carbon, (2) molybdenum-copper gradient doping repair of the SEI film, and (3) stable circulation of more than 5000 times at the capacity of 350mAh / g.

The invention discloses acrylic resin, a preparation method and application thereof, lithium ion battery negative electrode slurry and a negative electrode plate, and belongs to the technical field of lithium ion batteries. The invention provides acrylic resin which comprises the following raw materials in percentage by mass: 40-70% of A-type monomer, 10-30% of B-type monomer, 10-30% of C-type monomer and 10-30% of cross-linking agent, and the total mass of the monomers is 100%. The dosage of the monomer B is 10%-40%; the use amount of the class C monomer is 10%-40%; the dosage of the cross-linking agent is 0.5%-3% of the total mass of the monomer. The acrylic resin disclosed by the invention is good in thickening and dispersing performance, good in bonding performance and good in flexibility in a negative electrode slurry system with graphite as an active substance, and can completely replace a traditional thickening agent CMC, and a lithium ion battery negative electrode pole piece prepared from the acrylic resin has excellent thick coating anti-cracking performance and can be applied to lithium ion batteries. And the peeling strength of the pole piece can be greatly improved.

The invention relates to the technical field of lithium ion battery negative electrode materials, in particular to a coating modification method of a negative electrode material, the negative electrode material and application of the negative electrode material, and the negative electrode material sequentially comprises a silicon core, a gradient interface layer, a self-repairing elastic layer and a hierarchical porous carbon skeleton from inside to outside; the gradient interface layer coats the surface of the silicon core and sequentially comprises an amino silane coupling agent modification layer and a conductive polymer layer from inside to outside; the self-repairing elastic layer covers the outer side of the gradient interface layer and comprises a dynamic covalent bond cross-linked network; the hierarchical porous carbon skeleton coats the outer side of the self-repairing elastic layer, a strongly-combined gradient interface layer is firstly constructed on a silicon core through hydroxylation, amino silane coupling and conducting polymer in-situ polymerization, then a reversible cross-linked network is formed outside the gradient interface layer based on Diels-Alder dynamic covalent bonds, and in-situ crack repairing is achieved. And finally, biomass carbon and CVD carbon nanotubes are compounded, and a micropore / mesopore synergistic conductive buffer structure is formed outside the reversible cross-linked network, so that the cycling stability of the battery is improved.

The invention relates to the technical field of lithium batteries, in particular to a binder composition and application thereof, a negative electrode material, a negative electrode plate and a lithium ion battery. The binder composition comprises the following components in parts by weight: 100 parts of a binder; 0.1 to 10 parts of conductor polymer; 0-20 parts of a functional polymer; the conductor polymer is selected from one or more of imine covalent organic framework polymers; the functional polymer is selected from one or more of polymers capable of forming dynamic hydrogen bonds with the binder and / or the conductor polymer. The binder composition is used for the silicon-based lithium ion battery, can maintain the complete structures of the negative electrode of the lithium ion battery and an SEI membrane, and can improve the electrochemical performance of the lithium ion battery.

The invention relates to a negative electrode material, a preparation method thereof and a lithium ion battery, the negative electrode material comprises a silicon-based material and a coating layer located on at least part of the surface of the silicon-based material, the silicon-based material comprises silicon oxide and lithium silicate, and the material of the coating layer comprises a carbon material; the method comprises the following steps: dissolving 20 mg of a negative electrode material in 10 ml of deionized water to form slurry, carrying out a Zeta potential test on the slurry by adopting a nanometer particle size and Zeta potential analyzer, in a Zeta potential test distribution diagram of the slurry, the intensity of a first characteristic peak of the slurry in a Zeta potential interval of-50 mV to-40 mV is I1, the intensity of a second characteristic peak of the slurry in a Zeta potential interval of-65 mV to-50 mV is I2, and the first characteristic peak and the second characteristic peak are shown in the specification. The intensity of the third characteristic peak in the Zeta potential interval of-35mV to-25mV is I3, and the relation among I1, I2 and I3 meets the conditions that I2 / I1 is greater than or equal to 0 and less than or equal to 2.0, and I3 / I3 is greater than or equal to 0 and less than or equal to 1.0. According to the negative electrode material, the volume expansion of the negative electrode material can be reduced, and the rate capability and the cycle performance of the negative electrode material are improved.

The invention provides an amorphous nano oxide and a preparation method thereof, a negative electrode, a battery and an electric device, and relates to the technical field of lithium batteries. The preparation method comprises the following steps: carrying out coordination reaction on a raw material substance containing target metal ions and fumaric acid to obtain a metal organic framework material; and carrying out etching treatment on the metal organic framework material by utilizing ozone to obtain the amorphous nano oxide corresponding to the target metal ions. According to the preparation method provided by the invention, the metal organic framework material is etched by ozone, the oxide material is prepared and is used as the negative electrode material of the lithium ion battery, and the prepared oxide material is of an amorphous structure, has a nano-size and a porous structure, is beneficial to diffusion of lithium ions of the battery material, and effectively improves the cycle performance of the negative electrode material.