439 results about "Natural graphite" patented technology

The invention provides a negative plate and a battery. The negative plate comprises a negative current collector and a coating, and the coating is divided into an inner layer and an outer layer; the inner layer is close to the surface of the negative current collector and the outer layer is away from the surface of the negative current collector; the first negative electrode active substance of the inner layer comprises a silicon-based negative electrode material, and the silicon-based negative electrode material comprises at least one of silicon oxide, silicon carbide, nano silicon and silicon alloy. The second negative electrode active material of the outer layer comprises a carbon negative electrode material, and the carbon negative electrode material comprises at least one of natural graphite, artificial graphite, hard carbon, soft carbon, mesocarbon microbeads and graphene. By adopting the specific double-layer active material layer structure, the performance of the negative electrode is effectively improved, and the energy density and the fast charging performance of the battery are improved. Meanwhile, due to the special multi-layer structural design, the volume expansion effect of the silicon-based negative electrode material can be effectively relieved, the structural stability of the negative electrode is optimized, the structural stability of the negative electrode can be kept for a long time in the charge-discharge cycle, and then the battery performance is optimized.

The invention relates to a hydrogen storage pellet enabling the production of compact, modular, safe and energy-efficient hydrogen reservoirs. The pellet according to the invention comprises a peripheral ring (4) having an outer diameter of expanded natural graphite (ENG) of a determined height, surrounding a wafer of a metal hydride (5) in the form of compacted powder.

The invention discloses a negative electrode material, a negative electrode plate and a secondary battery, and relates to the technical field of secondary batteries. The negative electrode material comprises natural graphite and amorphous carbon filled in pores of the natural graphite; the particle hardness of the negative electrode material is 0.28 GPa to 0.4 GPa, and the elastic modulus of the negative electrode material is 7.0 GPa to 8.0 GPa; when the compaction density of the tablet of the negative electrode material is 1.5-2.0 g / cm < 3 >, the orientation OI value of the tablet of the negative electrode material is y, and y is more than 4 and less than or equal to 11. When the negative electrode material is applied to the secondary battery, the first coulombic efficiency and the cycling stability can be remarkably improved.

The invention provides an asphalt solid-phase composition for coating, a modified asphalt coated natural graphite negative electrode material, preparation of the modified asphalt coated natural graphite negative electrode material and a lithium ion battery, and the asphalt solid-phase composition for coating is used for forming an amorphous carbon coating layer coated on the surface of natural graphite and comprises coated asphalt and a modification additive, the mass ratio of the natural graphite to the coated asphalt to the modification additive is 1000: (45-80): (3-12); the modification additive comprises a saturated long-chain component, a low-molecular wax component and a component containing a modification group in a mass ratio of (2-10): (0.5-5): (0.5-7). By adding the modification additive, the softening point and viscosity of the asphalt are reduced, the wetting contact property of the asphalt to graphite is improved, the density and uniformity of a coating layer are improved, and the electrochemical performance of the natural graphite negative electrode material is further improved. The negative electrode material provided by the invention has higher first-cycle coulombic efficiency, better cycle performance, lower impedance and lower specific surface area under the condition of low asphalt addition amount.

The invention relates to the technical field of flux-cored wires. The preparation method comprises the following steps: weighing the following raw materials in parts by weight: 4-6 parts of chromium carbide powder, 7-9 parts of molybdenum powder, 6-8 parts of nickel powder, 10-15 parts of niobium powder, 15-18 parts of tungsten carbide powder, 7-11 parts of a modified titanium carbide agent, 5-8 parts of a blending agent added based on boron and 2-4 parts of 30-mesh natural graphite; 1-2 parts of sodium fluosilicate; 1-2 parts of aluminum powder; and 70-75 parts of iron powder. The flux-cored wire can adapt to complex service environments of parts such as rollers and continuous casting crystallizers in the metallurgical industry, the service life of the parts subjected to surfacing repair is prolonged, the production efficiency of the parts subjected to surfacing repair is improved, the obtained flux-cored wire achieves balance of high-temperature performance, mechanical performance and low-temperature stability, and the comprehensive applicability of products is improved.

The invention provides a lithium supplement composite layer and a preparation method thereof, a lithium supplement method, a pre-lithiated negative pole piece, a secondary battery and an electronic device, the lithium supplement composite layer comprises an interface layer and a lithium supplement layer which are laminated, the interface layer comprises interface particles and a binder, the interface particles comprise a lithium intercalation material and / or a conductive agent, and the binder comprises a lithium intercalation material and / or a conductive agent. The lithium intercalation material is selected from at least one of artificial graphite, natural graphite, hard carbon, a silicon-carbon material, a silicon-oxygen material, lithium titanate, tin and a tin-copper alloy, and the conductive agent is selected from at least one of conductive carbon black, carbon fiber, graphene and a carbon nanotube; the binder is selected from at least one of polytetrafluoroethylene, an ethylene-tetrafluoroethylene copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, polyvinylidene fluoride and polyoxyethylene; the lithium supplementing layer comprises lithium metal and / or lithium alloy. The lithium supplement composite layer meets the above characteristics, lithium supplement is carried out on the negative pole piece, the first coulombic efficiency of the secondary battery can be improved, the cycle capacity attenuation is reduced, and the energy density of the secondary battery is improved.

The invention provides natural graphite powder for a high-temperature gas cooled reactor nuclear fuel element and a preparation method of the natural graphite powder. The preparation method comprises the following steps: performing screening, crushing, shaping and grading treatment on graphite fine powder to obtain powder with the particle size of 25-35 microns; carrying out primary purification and secondary purification on the powder by using a mixed acid solution, heating the obtained chemically purified graphite powder in vacuum, carrying out high-temperature purification, introducing a mixed gas of argon and carbon tetrafluoride when the temperature reaches 1800 DEG C, and starting a circular reaction; then continuously carrying out gradient heating to 2000 DEG C, 2200 DEG C and 2400 DEG C, and respectively carrying out circular reaction at each temperature; then cooling to 300-400 DEG C, introducing mixed gas of oxygen and argon, and carrying out oxidation treatment; and finally, scattering and homogenizing to obtain a natural graphite powder finished product. The natural graphite powder provided by the invention realizes lower total impurity element content and total boron equivalent and higher specific surface area.

Disclosed is a negative electrode including a negative electrode active material layer, wherein the negative electrode active material layer includes a negative electrode active material and a conductive agent. The negative electrode active material includes carbon-based active material particles including natural graphite and an amorphous carbon-based material. The carbon-based active material particles have a specific surface area of 1.4 m2 / g to 2.3 m2 / g, and the conductive agent includes carbon nanotubes having an average length of 1 μm to 12 μm. A secondary battery including the negative electrode is also disclosed.

One aspect of the present invention provides: a precursor for a negative electrode material of a lithium secondary battery having high capacity characteristics, excellent processability, and excellent lifespan characteristics through a structure in which fine natural graphite is distributed in high-hardness artificial graphite; a negative electrode material manufactured therefrom; and a method for manufacturing same.

The invention discloses a preparation method of a defective graphene negative electrode for a lithium battery, which comprises the following steps: grinding natural graphite into powder, carrying out graphite modification by irradiation of a high-current pulse electron beam, mixing with a conductive agent and a binder to prepare slurry, and coating the slurry on a metal foil to prepare the defective graphene negative electrode for the lithium battery. Natural graphite is modified through high-current pulse electron beam irradiation, obvious expansion deformation occurs on the surface of the natural graphite, defects are generated on a graphite structure, mutual stripping between graphite layers is achieved, the whole surface of the graphite is in a hairy wrinkle form, the structure is almost transparent, and the storage capacity and the cycling stability are obviously improved; the obtained defective graphene negative electrode material provides more channels for lithium ion diffusion, the ion diffusion path is effectively shortened by internal gaps, and a physical method is adopted, a specific reducing agent, an oxidizing agent or other intermediate media do not need to be used, and introduction of impurities is avoided.

The invention belongs to the field of graphite materials, and particularly relates to nuclear-grade natural graphite, preparation of the nuclear-grade natural graphite and application of the nuclear-grade natural graphite to preparation of high-temperature gas cooled reactor fuel spherulis.The preparation method comprises the steps that a natural graphite raw material is subjected to first-stage heat preservation treatment at the temperature T1 in advance, and a first-stage material is obtained; grinding and grading the first-section material to obtain graphite powder A and graphite powder B; then shaping and grading the graphite powder A to obtain graphite powder C; mixing the graphite powder B and the graphite powder C to obtain graphite powder D; the graphite powder D is subjected to liquid phase treatment in acid liquor in advance, and graphite powder E is obtained; the graphite powder E is subjected to two-stage gas-solid treatment with gas control and pressure control, and the nuclear-grade natural graphite is prepared. According to the method, the purity of the graphite can be obviously optimized, and in addition, the loss of strength in the purification process can be avoided, so that the graphite which is more than 5N, ultralow in nuclear reaction degradation impurities, excellent in strength and capable of meeting the application requirements of a nuclear reaction device can be obtained.

The invention belongs to the technical field of semiconductor graphite materials, and particularly relates to a semiconductor graphite material and a preparation method thereof. The semiconductor graphite material comprises the following raw materials in percentage by mass: 23-33% of pitch coke powder, 23-33% of green petroleum coke powder, 5-15% of artificial graphite powder, 3-8% of natural graphite powder and the balance of modified pitch. The semiconductor graphite material disclosed by the invention has relatively high breaking strength, compressive strength, hardness and density; the prepared ceramic has low resistivity, porosity and ash content, the preparation process is simpler, and the production cost is reduced.

The invention discloses a negative electrode material, a negative electrode plate and a secondary battery, and relates to the technical field of secondary batteries. The negative electrode material comprises an inner core and a coating layer, the coating layer is located on the surface of the inner core, the inner core comprises natural graphite and first amorphous carbon filled in pores of the natural graphite, and the coating layer comprises second amorphous carbon; the Raman spectrum of the negative electrode material has a peak D and a peak G, and the intensity ratio of the peak D to the peak G is ID / IG; the inner core comprises an inner layer area and an outer layer area located outside the inner layer area, and the outer layer area is adjacent to the coating layer; the mean value of the ID / IG of the inner layer area is Ka, and the mean value of the ID / IG ratio of the inner layer area to the outer layer area is K; 0.4 < = Ka < = 0.7, and 0.5 < = K < 0.9. When the negative electrode material is applied to the secondary battery, the first coulombic efficiency can be remarkably improved, and the expansion rate can be reduced.

The invention belongs to the technical field of graphite powder processing, and particularly relates to natural graphite powder airflow shaping equipment which comprises a shaping box, supersonic airflow sprayers are installed on the periphery of the bottom end of the shaping box, a feeding assembly is installed in the middle of one side of the shaping box, a grading box is rotationally connected to the top end in the shaping box, and a discharging opening is formed in one end of the grading box. Grading holes are formed in the outer side of the grading box at equal intervals, a connecting box is arranged on one side in the grading box, a cleaning block is slidably connected into the connecting box, a baffle is arranged on the side, close to the connecting box, of the grading box, and a cleaning brush is rotatably connected to the lower portion of the baffle; the interior of the grading hole can be cleaned through a cleaning block, graphite powder can be prevented from being accumulated in the grading hole, meanwhile, the exterior of the grading box is swept through a cleaning brush in a matched mode, more comprehensive cleaning can be achieved, a connecting box and a baffle can move, and normal use of the grading box cannot be affected.

The invention relates to a battery monomer, a battery device and a power utilization device. A negative electrode material layer of the battery monomer comprises a first negative electrode film layer and a second negative electrode film layer; the first negative electrode film layer is closer to the negative electrode current collector than the second negative electrode film layer; the first negative electrode film layer comprises a first negative electrode active material and a first conductive agent, the first negative electrode active material comprises natural graphite, and the first conductive agent comprises a single-walled carbon nanotube; the second negative electrode film layer comprises a second negative electrode active material and a second conductive agent, the second negative electrode active material comprises artificial graphite, and the second conductive agent comprises a multi-walled carbon nanotube. The battery monomer provided by the invention has good cycle stability.

The invention discloses a silane functionalized graphene oxide / waterborne polyurethane hydrophobic coating and preparation, and belongs to the technical field of paints.The silane functionalized graphene oxide / waterborne polyurethane hydrophobic coating is prepared by the steps that natural graphite powder serves as a raw material, and graphene oxide is prepared through a Hummer method; n-(beta-aminoethyl)-gamma-aminopropyl trimethoxy silane is grafted to the surface of the graphene oxide through a chemical reduction method, and GO-AATS composite filler is obtained; then, castor oil is used as a soft segment, isophorone diisocyanate is used as a hard segment, and a series of GO-AATS-WPU emulsions are prepared. According to the silane functionalized graphene oxide / waterborne polyurethane hydrophobic coating and preparation, chemical bonds are formed between graphene oxide and waterborne polyurethane, and the interfacial compatibility of graphene oxide and waterborne polyurethane is improved, so that the mechanical property, water resistance, corrosion resistance and thermal stability of the waterborne polyurethane coating are improved.

The invention relates to the technical field of lithium battery negative electrode materials, in particular to a lithium battery graphite negative electrode material and a preparation method thereof. The preparation method of the graphite negative electrode material comprises the following steps: taking natural graphite as a raw material, sucking the natural graphite into a jet mill through a high-pressure fan for crushing, shaping, spheroidizing, shaping and the like to obtain a pre-product graphite powder, modifying the graphite powder, and performing secondary crushing and spheroidizing; according to the graphite negative electrode material prepared through modification and secondary spheroidization, the mechanical strength and the wear resistance of the material are improved, secondary spheroidization is facilitated, the spheroidization degree of the material is good, volume expansion is inhibited, the conductivity and the structural stability can be improved, and the service life of the material is prolonged. The cycle service life in the battery is prolonged; and the electrochemical performance is improved.

The invention specifically discloses a negative electrode active material and application thereof. The negative electrode active material comprises a carbon material and a silicon-based material, the carbon material comprises at least one of artificial graphite, natural graphite, soft carbon, hard carbon, mesocarbon microbeads and graphene; the chemical formula of the silicon-based material is XaSibYc, X comprises at least one of P, As, Se, B, Ga, Mg, Al, Zn and Li, Y comprises at least one of O and C, and a, b and c meet the conditions that a is larger than or equal to 0 and smaller than or equal to 8, c is larger than or equal to 0 and smaller than or equal to 10, (a + b) is larger than or equal to 1 and smaller than or equal to 10, and (b + c) is larger than or equal to 2 and smaller than or equal to 10. The method has the advantages of improving the energy density, the rate capability and the cycle performance of the lithium battery.

The invention provides a graphite composite negative electrode material and a preparation method thereof, and a lithium ion battery, the graphite composite negative electrode material has a core-shell structure, and comprises a graphite core, a mesh conductive intermediate layer and a surface soft carbon coating layer; the raw materials of the net-shaped conductive middle layer comprise polyhydroxy benzene and metal salt, the raw material of the graphite inner core comprises natural graphite, and the raw material of the surface soft carbon coating layer comprises high-temperature coating asphalt; the mass ratio of the natural graphite to the polyhydroxy benzene to the metal salt to the high-temperature coated asphalt is 1000: (20-80): (20-80): (20-60). According to the invention, the natural graphite negative electrode material with high first-cycle coulombic efficiency, high rate capability and excellent long cycle performance can be prepared.

The invention discloses fast charge graphite, a preparation method thereof and a lithium ion battery negative electrode material, and the preparation method comprises the following steps: carrying out acid leaching elution and alkali liquor neutralization on natural graphite fine powder to passivate the surface of the natural graphite fine powder; mixing the passivated graphite fine powder with boric acid and acetic acid, and then carrying out heating reaction to obtain modified graphite fine powder; mixing the modified graphite fine powder with a binder, and granulating to obtain secondary particles; after the secondary particles are subjected to graphitization treatment, the graphitized secondary particles are coated with a carbon source coating agent, and then carbonization treatment is conducted in the inert atmosphere; and carrying out vacuum impregnation on the carbonized secondary particles in a lithium source solution, and drying to obtain the lithium ion battery positive electrode material. The preparation method has the advantages that the interlayer spacing of the natural graphite can be expanded by modifying the natural graphite fine powder, and then the natural graphite is subjected to granulation, graphitization and carbon coating treatment and then is subjected to gradient coating, so that the prepared fast-charging graphite has more excellent dynamic performance.

The present disclosure provides a dry battery electrode comprising a. at least one active material; b. at least one conductive carbon; and c. at least one fluorinated binder; wherein the active material is selected from natural graphite, silicon, synthetic graphite, expanded graphite, or combinations thereof. The present disclosure further provides a lithium-ion battery comprising the dry battery electrode as disclosed herein. Furthermore, the present disclosure provides a process for preparing the electrode.

The application discloses a kind of negative active material and its application.A kind of negative active material, including carbon material and silicon-based material;The carbon material includes artificial graphite, natural graphite, soft carbon, hard carbon, mesophase carbon microsphere, at least one in graphene;The chemical formula of the silicon-based material is X a Si b Y c Wherein, X includes at least one of P, As, Se, B, Ga, Mg, Al, Zn, Li, Y includes at least one of O, C, a, b, c satisfy 0≤a≤8, 0≤c≤10, 1≤(a+b)≤10, 2≤(b+c)≤10.The application has the advantages of improving the energy density, rate performance and cycle performance of lithium battery.

The invention relates to a preparation method and application of modified micro-expansion spherical graphite, in particular to a preparation method and application of modified micro-expansion spherical graphite. In order to solve the problems of poor rate capability and poor cycle stability of a natural graphite negative electrode material, the surface-modified micro-expansion spherical graphite is obtained by performing oxidation modification treatment on spherical graphite by adopting an electrochemical oxidation technology. The interlayer spacing is enlarged, the diffusion resistance of lithium ions is reduced, and the rate capability is improved. An oxygen-containing functional group is introduced, so that a uniform and stable SEI film is formed, and the cycling stability is improved. The coated asphalt is used as a precursor, and the carbon-coated spherical graphite with a core-shell structure is obtained through a controllable carbonization technology. The carbon coating layer can effectively inhibit graphite stripping, pulverization and volume expansion, and the pore structure can improve the electrolyte compatibility and improve the cycle stability. The method is applied to the field of lithium ion battery negative electrode materials.

The present invention relates to an electrode for a secondary battery in which a first electrode material mixture layer including a first negative electrode active material, a first conductive agent, and a first binder is formed on a current collector, and a second electrode material mixture layer including a second negative electrode active material, a second conductive agent, and a second binder is formed on the first electrode material mixture layer, wherein the first negative electrode active material and the second negative electrode active material each include at least one selected from the group consisting of natural graphite and artificial graphite, and when the electrode is analyzed by a shear strength analysis method, a ratio of a maximum value (σmax) to a minimum value (σmin) in a simplified shear strength (σ) profile is 1.7 or less.

The present invention discloses a negative electrode material, a negative electrode sheet and a secondary battery, relating to the technical field of secondary batteries. The negative electrode material includes natural graphite and amorphous carbon filled in the pores of the natural graphite; the particle hardness of the negative electrode material is 0.28 GPa to 0.4 GPa, and the elastic modulus is 7.0 GPa to 8.0 GPa; when the compaction density of the tablet of the negative electrode material is 1.5 to 2.0 g / cm<supgt;3< / supgt;, the orientation OI value of the tablet of the negative electrode material is y, and 4 < y ≤ 11. Applying this negative electrode material to a secondary battery can significantly improve the first Coulomb efficiency and cycle stability.

A secondary battery and an electric device. The secondary battery comprises a negative electrode sheet; the negative electrode sheet comprises a negative electrode current collector and a negative electrode film layer; the negative electrode film layer has a first surface away from the negative electrode current collector and a second surface arranged opposite to the first surface; the thickness of the negative electrode film layer is recorded as H; a region extending from the second surface to a thickness of 0.3 H of the negative electrode film layer is recorded as a first region of the negative electrode film layer, the first region comprises a first negative electrode active material, and the first negative electrode active material comprises a first carbon-based material; a region extending from the first surface to a thickness of 0.3 H of the negative electrode film layer is recorded as a second region of the negative electrode film layer, the second region comprises a second negative electrode active material, and the second negative electrode active material comprises a second carbon-based material; the first carbon-based material comprises natural graphite; and a total hole area S2 of an internal region of the second carbon-based material is greater than a total hole area S1 of an external region of the second carbon-based material.

The invention relates to the technical field of graphite purification, and discloses a method for high-temperature purification of natural graphite by using light metal halide salt, which comprises the following steps: mixing a natural graphite raw material with composite light metal halide salt according to a mass ratio of 1: 0.1-0.3, the composite light metal halide salt comprising a mixture of chloride salt and fluoride salt; the method comprises the following steps: in a first stage, heating to 800-1000 DEG C under the protection of inert gas, and keeping the temperature for 1-2 hours; in the second stage, the atmosphere is switched into a reducing gas atmosphere, the temperature is increased to 1200-1400 DEG C, and heat preservation is conducted for 3-5 h; in the third stage, the temperature is raised to 1800-2000 DEG C by utilizing halogen gas generated by halogen salt pyrolysis, and heat preservation is carried out for 0.5-1 h; and performing acid pickling, water washing and vacuum drying on the pyrolysis product to obtain graphite. Compared with a traditional high-temperature purification method, the highest pyrolysis temperature is reduced by 500-800 DEG C, the energy consumption is reduced by 40-60%, the production cost is greatly reduced, and the economical efficiency and sustainability of the process are improved.

One aspect of the present invention provides a precursor for a negative electrode material of a lithium secondary battery, the negative electrode material prepared from the precursor, and a method for preparing the same, the precursor for the negative electrode material having high capacity characteristics, excellent processability, and excellent lifespan characteristics by a structure in which natural graphite fine powder is distributed in high-hardness artificial graphite.

The present application relates to the technical field of secondary batteries. Disclosed are a negative electrode material, a negative electrode sheet and a secondary battery. The negative electrode material comprises natural graphite and amorphous carbon filled into pores of the natural graphite. The particle hardness of the negative electrode material is 0.28-0.4 GPa, and the elastic modulus thereof is 7.0-8.0 GPa. When the compaction density of a tablet of the negative electrode material is 1.5 g / cm3 to 2.0 g / cm3, the orientation OI value of the tablet of the negative electrode material is y, and 4<y≤11. When the negative electrode material is applied to a secondary battery, the initial coulombic efficiency and the cycling stability can be significantly improved.

A method of preparing a negative electrode which includes preparing a negative electrode structure including expanded natural graphite, impregnating the negative electrode structure with a pre-lithiation solution to form an impregnated negative electrode structure, and pre-lithiating the impregnated negative electrode structure by electrochemically charging the impregnated negative electrode structure to 10% to 20% of charge capacity of the negative electrode structure.