50 results about "Natural graphite" patented technology

A natural graphite composite negative electrode material and a preparation method therefor, and a lithium-ion battery. The natural graphite composite negative electrode material comprises natural graphite, a fluffy net-shaped three-dimensional carbon network that coats the natural graphite, and an amorphous carbon coating layer arranged outside the fluffy net-shaped three-dimensional carbon network, wherein magnesium ions and / or aluminum ions are dispersed in the fluffy net-shaped three-dimensional carbon network, and the amorphous carbon coating layer is doped with copper particles and / or silver particles. The natural graphite composite negative electrode material has a three-dimensional conductive network, is doped with metals, and has a good conductivity and electrochemical cycle performance.

The present invention relates to a negative electrode composition comprising a silicon-based active material and a carbon-based active material, wherein the carbon-based active material comprises at least one of a silicon-carbon composite and a silicon oxide, and the rolling density decreases in the order of natural graphite > artificial graphite > silicon-based active material when powder resistance is measured at a pressure of 800 kgf / cm2, and the electrical conductivity decreases in the order of natural graphite > artificial graphite > silicon-based active material, and the negative electrode, a lithium secondary battery, a battery module, and a battery pack comprising the same.

The present invention relates to an anode active material comprising: natural graphite particles; and elemental iron, elemental silicon, and elemental sulfur present on the surface, inside, or both on the surface and inside the natural graphite particles, wherein the total content of the elemental iron, the elemental silicon, and the elemental sulfur is more than 5 ppm and 100 ppm or less on the basis of the total weight of the natural graphite particles, and the content of the elemental iron is 5-50 ppm on the basis of the total weight of the natural graphite particles.

Provided are a negative electrode material and a preparation method thereof and a lithium ion battery. The negative electrode material includes natural graphite and a coating layer coated on the surface of the natural graphite, and the compression index K of the negative electrode material is: 30≤K≤80; in which the compression index K=100(V0-VF) / V0, where V0 is the apparent volume per unit mass in a loose state, and VF is the tapped volume per unit mass. The negative electrode material of an embodiment has suitable powder fluidity, reduced functional groups on the surface of negative electrode material particles, is easy to disperse during processing, and at the same time, fewer functional groups on the surface reduce side reactions during high temperature storage, thereby improving the high temperature storage performance of the negative electrode material.

Disclosed are a dry negative electrode plate for a rechargeable lithium battery and a rechargeable lithium battery including the same. The dry negative electrode plate for a rechargeable lithium battery includes a negative electrode active material and a binder, and the negative electrode active material includes a mixture of a first negative electrode active material, a second negative electrode active material, and a third negative electrode active material, the first negative electrode active material including natural graphite including secondary particles arranged of primary particles, and a coating including amorphous carbon and surrounding the secondary particles, the first negative electrode active material having an orientation degree of 90 or less and a d002 of 3.356 Å to 3.360 Å, the second negative electrode active material including artificial graphite, and the binder including polytetrafluoroethylene, polyvinylidene fluoride, polyolefin, or a mixture thereof.

Disclosed are a negative electrode active material for a rechargeable lithium battery and a rechargeable lithium battery including the same. The negative electrode active material includes a mixture of a first negative electrode active material and a second negative electrode active material, the first negative electrode active material includes natural graphite and a coating layer, the natural graphite includes secondary particles in which primary particles are disposed, the coating layer includes amorphous carbon and surrounds the secondary particles, the first negative electrode active material has an orientation degree of 90 or less and a d002 value of 3.356 Å to 3.360 Å, and the second negative electrode active material includes rod-like artificial graphite.

The application discloses a double-layer negative plate preparation method in the field of energy storage equipment. The preparation process comprises three main steps: firstly, negative electrode slurry A is prepared, hard carbon, conductive carbon black, natural graphite, single-walled carbon nanotube dispersion liquid and polyvinylidene fluoride are stirred and uniformly mixed in a dry room with a dew point of-30 to-40 DEG C according to a specific mass ratio, and 1-methyl-2-pyrrolidone is added and stirred uniformly; secondly, negative electrode slurry B is prepared, and the process is similar to that of A, but a part of the hard carbon is replaced by an HL mixture (mixed uniformly by hard carbon and lithium cobalt nitride according to a specific ratio); finally, a double-layer negative plate is prepared, a layer of negative electrode slurry A or B is coated on both sides of the copper current collector and first dried, another layer is coated and second dried, and finally, the double-layer negative plate is obtained through rolling and cutting. The double-layer negative plate design aims to solve the problems of low first effect of hard carbon and insufficient power density in the super-high rate constant-current discharge.

This application provides a negative electrode material and a battery. The negative electrode material includes a core and amorphous carbon located on at least a portion of the surface of the core. The core includes natural graphite. The particles of the negative electrode material have pores. In a cross-sectional SEM image of the negative electrode material, 20 pores are randomly selected for measurement. The average width of the pores is D, the average length of the pores is L, and the average aspect ratio of the pores is L / D ≥ 2.5. Twenty particles are randomly selected from the SEM image for measurement. The area of ​​all pores and the total cross-sectional area of ​​each particle are measured. The average area ratio of pores in the total cross-sectional area is calculated to be 5%~15%. The negative electrode material provided by this application can improve the expansion performance during cycling and increase the cycle life of the negative electrode material.

The present application relates to lithium battery mechanism technical field, specifically for a kind of spheroidization shaping processing method and equipment of graphite negative electrode material for lithium battery, including steel frame and cyclone separator installed in steel frame inside, the bottom of the cyclone separator is equipped with discharge valve, the bottom of the discharge valve is fixedly connected with upper fixed frame, the bottom of the upper fixed frame is provided with collection mechanism, the left and right sides of the collection mechanism are both provided with fixed mechanism, the bottom of the collection mechanism is provided with collection box, the present application is provided with magnetic plate outside filter bag, utilizes magnetic field to penetrate filter bag wall, can directly adsorb and lock the falling material and the fine iron filings ascending with waste gas, since collection box is located in filter bag interior, all through material and airflow are in magnetic field coverage range, realize to the " bottom-up type " capture of fine iron impurities, effectively solve the problem of fine iron filings escape in traditional process, substantially improve the electrochemical stability of negative electrode material.

A negative electrode plate for a rechargeable lithium battery and a rechargeable lithium battery are provided. The negative electrode plate for a rechargeable lithium battery can include a negative electrode active material, which can include a first negative electrode active material, a second negative electrode active material, and a third negative electrode active material. The first negative electrode active material can include natural graphite and a coating layer. The natural graphite can include secondary particles. The secondary particles can include an aggregate of primary particles. The coating layer can include amorphous carbon and surround the secondary particles of the natural graphite. The first negative electrode active material can have an orientation degree of 90 or less and can have a d002 in a range of about 3.356 Å to about 3.360 Å. The second negative electrode active material can include graphite. The third negative electrode active material can have a sphericity of about 0.9 to about 1.0 and can include silicon nanoparticles and an amorphous carbon coating layer disposed on a surface of the silicon nanoparticles.

The present invention relates to a method for preparing lithium sulfide, the method comprising the steps of: preparing a lithium-carbon compound by mixing a carbon reducing agent and a lithium compound; filtering a solution in which the lithium-carbon compound and a solvent are mixed; and drying the filtrate, wherein the carbon reducing agent comprises natural graphite.

The present invention relates to a negative electrode plate for a rechargeable lithium battery and a rechargeable lithium battery including the same, wherein the negative electrode plate includes a negative electrode active material that includes a mixture of a first negative electrode active material, a second negative electrode active material, and a third negative electrode active material, the first negative electrode active material includes natural graphite including secondary particles in which primary particles are assembled and an amorphous carbon coating layer containing amorphous carbon and surrounding the secondary particles, and has an orientation degree of 90 or less and a d002 value of 3.356 Å to 3.360 Å, the second negative electrode active material is artificial graphite, and the third negative electrode active material includes a composite of silicon and crystalline carbon; and an amorphous carbon coating layer containing amorphous carbon and formed on the surface of the composite.

A negative electrode active material for a rechargeable lithium battery and a rechargeable lithium battery including the same are disclosed. A negative electrode active material includes a mixture of a first negative electrode active material and a second negative electrode active material, the first negative electrode active material includes natural graphite including secondary particles in which primary particles are arranged; and a coating layer containing amorphous carbon and surrounding the secondary particles, the first negative electrode active material has an orientation degree of 90 or less and a d002 value of 3.356 Å to 3.360 Å, and the second negative electrode active material includes rod-shaped artificial graphite.

Negative electrode for a secondary battery, comprising: a current collector; a first active material layer of the negative electrode provided on the current collector;and a second active material layer of the negative electrode provided on the first active material layer of the negative electrode, wherein the porosity of the second active material layer of the negative electrode is 5% to 20% higher than the porosity of the first active material layer of the negative electrode, wherein the first and second active material layers of the negative electrode each comprise an active material of the negative electrode, wherein the active material of the negative electrode comprises a silicon-based active material, synthetic graphite and natural graphite, and the silicon-based active material comprises at least one of SiOx(0≤x<2), SiMy(M is metal, 1≤y≤4) and Si / C, and wherein the silicon-based active material is contained in an amount of 1 to 40 parts by weight based on a total of 100 parts by weight of the active material contained in each of the first and second active material layers of the negative electrode.

This application relates to the field of reinforcing materials, specifically disclosing a graphene-calcium carbonate composite material, its preparation method, and its application. The preparation method includes the following steps: S1, adding natural graphite to an aqueous solution of sodium carboxymethyl cellulose and ball milling it under supercritical carbon dioxide conditions to obtain a graphene nanosheet dispersion; S2, adding calcium chloride solution to the graphene nanosheet dispersion, adjusting the pH to 8-11, stirring, and obtaining a mixed solution; S3, adding sodium carbonate solution dropwise to the mixed solution, reacting, then centrifuging, washing with water, and drying to obtain the graphene-calcium carbonate composite material. This application also discloses the application of the graphene-calcium carbonate composite material prepared by the above method in cement-based composite materials. This application has the characteristic of achieving an organic combination of graphene and calcium carbonate, which can better enhance the function of cement-based materials.

This invention relates to the field of bipolar plate technology, specifically to a high-strength graphite bipolar plate and its preparation method, which is prepared from the following raw materials in parts by weight: 60-80 parts of natural graphite powder, 12-18 parts of modified epoxy resin, 8-12 parts of reinforcing additives, 2-4 parts of conductive agent, 1-3 parts of curing agent, 0.5-2 parts of dispersant, and 0.3-1 parts of coupling agent. This invention uses a ternary compound of bisphenol A epoxy resin, phenolic epoxy resin, and organic fluorine epoxy resin, and combines it with binary graft modification of KH560 and fluorosilicone coupling agent. This significantly improves the interfacial compatibility, bonding strength, and hydrophobic and humid heat resistance of the resin matrix and inorganic fillers, enabling the bipolar plate to maintain high strength while significantly improving flexibility and dimensional stability. It effectively solves the defects of traditional epoxy resins, such as high brittleness, poor weather resistance, and weak bonding with fillers, laying a foundation for high strength, high toughness, and high weather resistance from the matrix level.

The present invention relates to a negative electrode plate for a rechargeable lithium battery and a rechargeable lithium battery including the same, in which the negative electrode plate includes a negative electrode active material including a mixture of a first negative electrode active material, a second negative electrode active material, and a third negative electrode active material, the first negative electrode active material includes natural graphite including secondary particles assembled of primary particles, and an amorphous carbon coating layer containing amorphous carbon and surrounding the secondary particles, and has an orientation degree of 90 or less and a d002 value of 3.356 Å to 3.360 Å, the second negative electrode active material is artificial graphite, and the third negative electrode active material includes a composite of silicon and crystalline carbon, and an amorphous carbon coating layer containing amorphous carbon and formed on a surface of the composite.

The application belongs to the technical field of composite materials, and discloses a preparation method of nickel-coated graphene and application of the nickel-coated graphene in aluminum-based composite materials. The preparation method comprises the following steps: obtaining graphene nanosheets by pretreating natural graphite; forming a nickel catalytic seed layer through stannous chloride sensitization and sodium borohydride activation; and performing chemical plating in a plating solution containing nickel sulfate hexahydrate, sodium citrate, ammonium chloride and sodium hypophosphite monohydrate to obtain nickel-coated graphene with a 3-10 nm continuous nickel shell layer on the surface. The nickel-coated graphene is mixed with aluminum-silicon-magnesium alloy powder and ball milled, and then subjected to low-temperature reaction at 350-450 DEG C to generate Al3Ni phase, high-temperature hot pressing densification at 600-650 DEG C to obtain aluminum-based composite materials. The method can effectively control Al-C interface reaction, inhibit the generation of Al4C3, improve the mechanical properties and electrical conductivity of the composite materials, and is suitable for large-scale application.

The present invention provides a heating diaphragm, a method for manufacturing the same, a heating tube, and a heating electrical device. The raw materials for the heating diaphragm include natural graphite and / or graphene, and the weight of a heating diaphragm with a length of 1 decimeter is 0.02 to 2 g.

This invention relates to the field of graphite materials technology, and more particularly to a method and application for modifying graphite tail powder generated during the graphite powdering and shaping process for the preparation of anode materials. The method uses tail powder generated during the powdering and shaping of raw coke or natural graphite as the main raw material. Through oxidation pretreatment, oxygen-containing functional groups are introduced onto the surface of the graphite tail powder. During pyrolysis, these groups form a stable C-O-C chemical bond interface with a carbonaceous binder phase. The isotropic carbonaceous binder phase formed by the pyrolysis of thermoplastic carbonaceous raw materials encapsulates the graphite tail powder, effectively reducing the anisotropy of the graphite tail powder crystals. The heteroatoms in situ doped in the carbonaceous binder phase expand the carbon interlayer spacing, providing more lithium-ion transport channels. Furthermore, this method is simple and suitable for large-scale engineering applications of high-value utilization of graphite tail powder.

Provided are a negative electrode active material for a rechargeable lithium battery, and a negative electrode plate and a rechargeable lithium battery including the same. The negative electrode active material includes natural graphite and a coating layer, the natural graphite including secondary particles assembled from primary particles, the coating layer surrounding the secondary particles and including amorphous carbon. The negative electrode active material has a d002 value of 3.356 Å to 3.360 Å and an orientation degree of 90 or less.

This invention relates to the field of sliding materials for seismic isolation bearings, specifically disclosing a high thermal conductivity and wear-resistant composite material for building seismic isolation bearings and its preparation method. The high thermal conductivity and wear-resistant composite material for building seismic isolation bearings comprises the following raw material components: aliphatic polyketone, high-styrene resin modified methyl vinyl silicone rubber, silicone resin, polytetrafluoroethylene, thermally conductive components, lubricant, compatibilizer, light stabilizer, antioxidant, and coupling agent; the thermally conductive components include the following raw material components: flake natural graphite, hexagonal boron nitride, and expanded graphite. The high thermal conductivity and wear-resistant composite material for building seismic isolation bearings of this invention exhibits high strength, stable energy dissipation performance, excellent thermal conductivity and heat dissipation capacity, and long-term wear resistance and durability under high temperature, high pressure, large displacement, and multi-cycle comprehensive working conditions, thereby effectively overcoming the problems of softening and heating, severe wear, and performance degradation of existing bridge seismic bearing materials during strong earthquakes and long-term service.

An asphalt solid-phase composition for coating, a modified asphalt-coated natural graphite negative electrode material, preparation therefor, and a lithium ion battery. The asphalt solid-phase composition for coating is used for forming an amorphous carbon coating layer covering the surface of natural graphite, and comprises asphalt for coating use and a modification additive, wherein the mass ratio of the natural graphite, the asphalt for coating use and the modification additive is 1000:45-80:3-12; and the modification additive comprises a saturated long-chain component, a wax component having a low molecular weight and a component containing a modification group which are in a mass ratio of 2-10:0.5-5:0.5-7. In the present invention, by adding the modification additive, the softening point and viscosity of asphalt are reduced, thereby improving the wetting contact property of asphalt with graphite, improving the density and uniformity of coating layers, and further improving the electrochemical properties of a natural graphite negative electrode material. The negative electrode material of the present invention exhibits higher first-cycle Coulombic efficiency, better cycle performance, lower impedance and lower specific surface area under low asphalt dosage conditions.

Disclosed are a negative electrode plate for a rechargeable lithium battery and a rechargeable lithium battery including the same. The negative electrode plate includes a negative electrode active material. The negative electrode active material includes a mixture of a first negative electrode active material, a second negative electrode active material, and a third negative electrode active material. The first negative electrode active material includes natural graphite including secondary particles each formed of primary particles, and an amorphous carbon coating layer surrounding the secondary particles, and the first negative electrode active material has an orientation degree of 90 or less and a d002 of 3.356 Å to 3.360 Å. The second negative electrode active material is graphite. The binder includes a (meth)acrylic-based binder.

To provide a negative electrode for lithium secondary batteries that has high capacity and excellent charging characteristics. [Solution] The present invention relates to a negative electrode for a lithium secondary battery and a lithium secondary battery including the same, and more particularly to a negative electrode for a lithium secondary battery and a lithium secondary battery including the same, comprising a negative electrode current collector and a negative electrode active material layer on the negative electrode current collector, wherein the negative electrode active material layer comprises a first negative electrode active material layer and a second negative electrode active material layer sequentially stacked on the negative electrode current collector, each of the first and second negative electrode active material layers comprising natural graphite and artificial graphite, the average particle size D50 of the natural graphite being smaller than the average particle size of the artificial graphite, and the ratio of the weight of the natural graphite to the weight of the artificial graphite in the second negative electrode active material layer being 1 to 5.

This invention provides a negative electrode material, a method for manufacturing the same, and a lithium-ion battery. [Solution] The negative electrode material includes natural graphite and a coating layer covering the surface of the natural graphite. The compression index K of the negative electrode material is 30 ≤ K ≤ 80. The compression index K = 100(V0 - V F ) / V0, where V0 is the apparent volume per unit mass in the dispersed state, V F This is the tap volume per unit mass. The anode material of the present invention has appropriate powder fluidity, reduces the functional groups on the surface of the anode material particles, improves dispersibility during processing, and, because there are fewer functional groups on the surface, reduces side reactions during high-temperature storage, thereby improving the high-temperature storage performance of the anode material.

The present disclosure provides a composite phase change heat storage material and a preparation method thereof, which uses hydrophilic modified natural graphite as a heat conducting material in the heat storage material, effectively improves the interfacial compatibility between the heat conducting material and the phase change material, and further improves the dispersibility, so that the prepared heat storage material has a higher phase change enthalpy retention rate and thermal conductivity.

This invention relates to a negative electrode active material, a negative electrode for a lithium secondary battery comprising the same, and a lithium secondary battery. The negative electrode active material comprises a silicon-based active material and graphite, wherein the graphite comprises natural graphite and artificial graphite, the absolute value of the ratio of the difference in average particle size (D50) between the natural graphite and the artificial graphite to the average particle size of the artificial graphite is 10% or less, and the absolute value of the ratio of the difference in average particle size (D50) between the silicon-based active material and the artificial graphite to the average particle size of the artificial graphite is 40% or less.