48results about How to "Increase sodium storage capacity" patented technology

The invention provides an asphalt-based closed-pore carbon material, a preparation method thereof and a sodium ion battery, the preparation method of the asphalt-based closed-pore carbon material comprises the following steps: S1, pre-oxidizing an asphalt-based carbon source in an oxidizing gas atmosphere at 200-350 DEG C to obtain a pre-oxidized product; s2, carrying out low-temperature carbonization on the pre-oxidized product in an inert atmosphere at 300-800 DEG C to obtain a first precursor; s3, performing gas activation on the first precursor in an activated gas atmosphere to obtain a second precursor; s4, performing chemical activation on the second precursor by adopting a chemical activating agent to obtain a porous carbon material; s5, dipping the porous carbon material in an asphalt solution, and then separating and drying to obtain a blank; and S6, carbonizing the blank under the protection of inert gas to obtain the asphalt-based closed-cell carbon material. The asphalt-based closed-cell carbon material has the advantages of high capacity, high first efficiency and high stable circularity.

The invention discloses a method for preparing a high-lignification biomass-based hard carbon material by water / alcohol synergistically assisted steam explosion, which comprises the following steps: soaking, washing, drying and crushing high-lignification biomass, adding water and alcohol reagents for soaking, then treating the material for 1-60 minutes under the conditions that the steam pressure is 1-3 MPa and the temperature is 150-280 DEG C, and then releasing pressure and exploding to obtain the high-lignification biomass-based hard carbon material. And performing low-temperature carbonization, impurity removal treatment, high-temperature carbonization, crushing and grading to obtain the high-lignification biomass-based hard carbon material. The invention also discloses the hard carbon material prepared by the preparation method and a sodium ion battery containing the hard carbon material. The high-lignification biomass-based hard carbon material prepared by water / alcohol synergistic auxiliary steam explosion has the advantages of high sodium storage capacity, high reversible capacity, excellent rate capability and the like when being used as a sodium ion battery negative electrode material.

The invention relates to a hard carbon material and a preparation method thereof, a negative pole piece and a battery. The preparation method of the hard carbon material comprises the following steps: carrying out pre-oxidation treatment on a plastic precursor to obtain pre-oxidized plastic; adding the obtained pre-oxidized plastic into a mixed solution of deionized water and alcohol, then adding 2, 6-dipicolinic acid, and carrying out a cross-linking reaction to obtain a plastic-based resin carbon precursor; and carbonizing the obtained plastic-based resin carbon precursor at high temperature to obtain the hard carbon material. The hard carbon material prepared by using the preparation process of the hard carbon material provided by the invention is stable in structure, and shows good sodium storage capacity and excellent rate and cycle performance.

The invention discloses a coal-based hard carbon material as well as a preparation method and application thereof. The method comprises the following specific steps: crushing and screening a coal-based raw material, pickling and deliming to obtain ultra-pure coal powder; mixing the ultra-pure pulverized coal with the soft carbon precursor, and performing carbonization treatment in an inert atmosphere; and mixing the carbonized sample with a solvent, and carrying out secondary sintering and curing to obtain the coal-based hard carbon material. The soft carbon precursor coating layer is used for reducing surface irreversible defects and improving coulombic efficiency and electronic conductivity, oxygen-containing functional groups such as carbonyl are introduced and cured in combination with the capacity increasing agent and secondary sintering, more reversible active sites are provided, and higher disorder degree and more excellent electrochemical performance are obtained. The preparation method is low in raw material cost and simple in treatment process, and is a sodium ion battery negative electrode material with commercialization prospects.

The invention provides a starch-based hard carbon negative electrode material, a preparation method thereof and a sodium ion battery, and belongs to the technical field of battery materials. The starch-based hard carbon negative electrode material comprises single crystal particles, the single crystal particles comprise polygonal particles with angular morphology, and the angular degree is 90-130 degrees. The single crystal particles in the starch-based hard carbon negative electrode material provided by the invention are regular in morphology and have a corner angle morphology with a specific angle, the phenomenon of particle aggregation and fusion can be avoided, the physicochemical properties of the starch-based hard carbon negative electrode material are remarkably improved, the particle size distribution is uniform, the compaction is improved, and meanwhile, the sodium storage sites are also increased; the sodium storage capacity and the first effect are favorably improved.

The invention provides a sodium battery core-shell type hard and soft interwoven carbon layer coated metal oxide negative electrode material, which is prepared from the following raw materials: an asphalt material, a hard carbon precursor, a metal oxide precursor and template salt, and the mass ratio of the asphalt material to the hard carbon precursor to the metal oxide precursor to the template salt is 1: (0.5-2): (1-2): 4; the core-shell type negative electrode material comprises a metal oxide and a hard-soft interwoven carbon layer coated on the surface of the metal oxide. On the other hand, the invention also provides a preparation method of the core-shell type hard-soft interwoven carbon layer coated metal oxide negative electrode material for the sodium battery, namely a one-step pyrolysis method. The problems that in the prior art, the defect that a metal oxide negative electrode is prone to pulverization or poor in conductivity can only be singly improved, and meanwhile, the formula is complex, the cost is high or the environment is polluted are solved, the defects that the electrode is prone to pulverization and poor in conductivity are synchronously improved, and the service life of the electrode is prolonged. And the performance of the electrode is improved to the maximum extent.

The invention relates to the technical field of battery material preparation, and provides a coal-based hard carbon negative electrode material, a preparation method thereof and a sodium ion battery. The preparation method of the coal-based hard carbon negative electrode material comprises the following steps: (I) uniformly mixing pulverized coal, alkali and water, and drying to obtain a mixture, wherein the mass ratio of the pulverized coal to the alkali to the water is 1: (0.01-0.8): (1-10); (II) performing low-temperature carbonization and activation on the mixture in a first inert atmosphere to obtain a first precursor, wherein the low-temperature carbonization and activation temperature is 450-1000 DEG C; (III) carrying out acid pickling, water washing and drying on the first precursor to obtain a second precursor; and (IV) carbonizing the second precursor in a second inert atmosphere. The coal-based hard carbon negative electrode material prepared by the invention has relatively low ash content and a proper closed-pore structure, and shows relatively high specific capacity and first coulombic efficiency when being used as a sodium-ion battery negative electrode material.

The invention relates to the technical field of sodium ion battery negative electrode materials, and discloses an in-situ doped pre-oxidized heavy organic matter hard carbon preparation method which comprises the following steps: step 1, low-temperature oxidation: obtaining a pre-oxidized carbon material after heat treatment is finished; step 2, element doping: obtaining a hard carbon precursor doped with a sulfur element; step 3, low-temperature curing: obtaining a cured sulfur element doped pre-oxidized heavy organic matter hard carbon precursor; step 4, high-temperature carbonization: obtaining a sulfur element doped pre-oxidized heavy organic matter hard carbon precursor material with a stable structure; the medium-temperature coal pitch is oxidized at low temperature to obtain the pre-oxidized carbon material, then the sulfur element doped material reacts with the medium-temperature coal pitch at low temperature, hydrogen ions of the medium-temperature coal pitch are substituted by sulfur to form relatively stable chemical bonds, and the continuity of the chemical bonds is beneficial to enhancing the stability of the structure; sulfur atom doping not only provides active sites and increases sodium storage capacity, but also expands interlayer spacing and improves rate capability.

The invention discloses high-capacity fast-charging hard carbon with precise regulation and control of confinement carbonization of a monatomic composite material as well as a preparation method and application of the high-capacity fast-charging hard carbon. According to the method, micropore-rich porous carbon is used as a carrier, a metal compound and a high-molecular polymer are compounded for one-step carbon thermal reduction, monatomic metal nanoparticles are introduced into high-capacity fast-charge hard carbon, and the sodium storage capacity of the material is further improved. The micropore-rich porous carbon is coordinated with a metal compound group through a carbon-oxygen single bond and a carbon-carbon single bond, superfine metal nanoparticles are subjected to in-situ carbon thermal reduction in micropores, the metal nanoparticles have high sodium storage capacity, and the micropore structure of the porous carbon can be used as a framework material to solve the problem of poor cycle performance caused by volume expansion.

The invention discloses a hard carbon material, a preparation method thereof, a pole piece, application and an electrochemical device. The preparation method of the hard carbon material comprises the following steps: sequentially carrying out heat treatment, carbonization treatment and carbon coating on a mixture of a carbon precursor and an activating agent to obtain the hard carbon material, the carbonization treatment temperature is higher than the heat treatment temperature; the heat treatment temperature is 700-900 DEG C; the hard carbon material prepared by the invention has a relatively large closed pore volume, and a battery assembled by the hard carbon material has relatively good electrochemical performance, and particularly has relatively good initial coulombic efficiency.

The invention belongs to the technical field of sodium ion batteries, and particularly relates to a soft and hard carbon composite material and preparation and application thereof.The soft and hard carbon composite material is of a double-sulfur-rich core-shell structure with soft carbon coated with hard carbon, the soft carbon serving as an inner core is sulfur-doped mesocarbon microbead-based secondary pore carbon, and the sulfur-doped mesocarbon microbead-based secondary pore carbon serves as an outer core; the hard carbon serving as the shell is sulfur-doped PEDOT (poly (3, 4-ethylenedioxythiophene))-based hard carbon. The core-shell structure is constructed by means of surface chemical modification, pore structure regulation and control, soft and hard carbon compounding and the like of the mesocarbon microbeads, the technical problem that the sodium storage capacity of the pitch-based soft carbon anode needs to be improved is solved, considerable intercalation capacity can be obtained by means of widened carbon layer spacing, and the sodium storage capacity of the pitch-based soft carbon anode can be improved. And abundant sodium storage sites can be obtained to realize large-proportion surface capacitance storage, so that the first charge-discharge capacity, the first efficiency and the cycle performance of the sodium ion battery (sodium battery) are improved.

The invention belongs to the technical field of energy storage materials, and particularly relates to a hard carbon material prepared from atmosphere-modulated hard carbon closed pores and pseudo-graphite domains as well as a preparation method and application of the hard carbon material. Biomass walnut shells are used as raw materials, argon atmosphere or air pre-oxidation is combined with high-temperature treatment of argon atmosphere or hydrogen-containing mixed gas, and closed pores of hard carbon and pseudo-graphite domains are modulated by changing the atmosphere. The raw materials used in the method are low in cost, and the method is simple and easy for large-scale production. The hard carbon material obtained by the invention has good conductivity and rapid ion transmission characteristic; the first coulombic efficiency is obviously improved, and the modulated rich closed-pore structure is beneficial to realizing the sodium storage capacity of a high platform.

The invention relates to the technical field of electrochemical energy storage materials, in particular to a high-performance nitrogen-doped hard carbon negative electrode material prepared on the basis of waste graphite and a preparation method and application of the high-performance nitrogen-doped hard carbon negative electrode material. The preparation method comprises the following steps: crushing and screening graphite, mixing graphite powder with glucose, adding ammonia water, stirring, then adding urea as a nitrogen source, and preserving heat at 1000 + / -50 DEG C to obtain the high-performance nitrogen-doped hard carbon negative electrode material. According to the preparation method provided by the invention, the interlayer spacing of the hard carbon material can be increased, the nitrogen content is increased, the quick charge performance of the material is improved, and the preparation method has relatively high practical value and application prospect.

The invention provides a negative electrode material and a preparation method thereof, and a battery, the negative electrode material comprises a carbon matrix and a carbon nanotube, at least a part of the carbon nanotube is inserted into the carbon matrix and forms a support structure; wherein the compaction density of the negative electrode material is greater than or equal to 1.3 g / cm < 3 >, and the powder conductivity of the negative electrode material under the pressure of 20KN is 9.0 * 10 < 3 > S / m to 4.0 * 10 < 4 > S / m; and the sodium embedding capacity of a button cell assembled by the negative electrode material in a slope region of a voltage interval of more than 0.1 V is more than or equal to 150mAh / g. According to the negative electrode material, the preparation method thereof and the battery provided by the invention, the negative electrode material has high capacity, high first efficiency and high conductivity.

The invention discloses an anthracite-based hard carbon negative electrode sodium storage material as well as a preparation method and application thereof. The invention relates to the technical field of electrode materials. The preparation method comprises the following steps: S1, taking anthracite as a base material, and preparing a porous carbon intermediate by adopting an alkali activation method; s2, carrying out oxidation modification on the porous carbon intermediate; and S3, performing high-temperature carbonization on the oxidized and modified porous carbon intermediate to obtain the anthracite-based hard carbon negative electrode sodium storage material. The anthracite-based hard carbon negative electrode sodium storage material with high initial coulombic efficiency and high specific capacity is prepared by combining an alkali activation method and a chemical oxidation method, and the commercial hard carbon requirement is met.

The application relates to the technical field of sodium ion battery positive electrode materials, in particular to a Na2Fe2(SO4)3@Na3Fe2(SO4)3F@CNT positive electrode material.The Na2Fe2(SO4)3 and Na3Fe2(SO4)3F precursors are mixed and sintered, and are coated by CNT, so that the electrochemical performance of the Na2Fe2(SO4)3 is remarkably improved, the conductivity of the material is improved, the material can be used as a sodium ion battery positive electrode material, has a high discharge specific capacity, and has cycle performance and rate performance.

The invention relates to the technical field of sodium ion batteries, and in particular to a MOF-derived screening type carbon sodium negative electrode material and a preparation method and application thereof. The preparation method comprises: preparation of a MOF-derived porous carbon material precursor and preparation of a screening type carbon negative electrode material, wherein the MOF-derived porous carbon material precursor is prepared by heat-treating and modifying a MOF material and a nitrogen source; the screening type carbon negative electrode material is prepared by chemical vapor deposition processes of the MOF-derived porous carbon material precursor twice at the same temperature and with different carbon source gases; the MOF-derived screening type carbon sodium negative electrode material has a rich closed-pore structure and the pore size of micropores in the closed-pore structure is adjustable, and is used in a sodium ion battery, with a first-cycle reversible capacity of 419 mAh / g, an initial coulombic efficiency of 89%, and a capacity retention rate of up to 75% at -30°C. Compared with the prior art, the technical problem that the prior art cannot have both a rich closed-pore structure and an adjustable pore size, resulting in poor energy density and poor low-temperature performance of the sodium ion battery, is solved.

The application provides a sodium ion battery negative electrode material and a preparation method thereof. The preparation method of the sodium ion battery negative electrode material comprises the following steps: obtaining a coal-based raw material; performing a defect operation on the coal-based raw material, so that the coal-based raw material is oxidized and crosslinked to obtain a pre-oxidized coal-based negative electrode material; performing a hot extraction treatment on the pre-oxidized coal-based negative electrode material to remove organic impurities in the pre-oxidized coal-based negative electrode material; and performing a high-temperature doping operation on the pre-oxidized coal-based negative electrode material after the hot extraction treatment to obtain the sodium ion battery negative electrode material. The preparation method of the sodium ion battery negative electrode material can effectively change the disorder degree of the microstructure, increase the interlayer spacing of the coal-based raw material, and further effectively improve the reversible specific capacity and the cycle performance.

The invention discloses a soft carbon coated sulfur-nitrogen co-doped coal-based hard carbon material and a preparation method thereof.The preparation method comprises the steps that firstly, bituminous coal powder and thiourea particles are dissolved in absolute ethyl alcohol, fully stirred and mixed to be uniform, and after drying, bituminous coal-thiourea mixed powder is prepared; carrying out primary carbonization treatment on the bituminous coal-thiourea mixed powder in an inert atmosphere to prepare a sulfur-nitrogen co-doped coal-based hard carbon material; and depositing asphalt on the surface of the sulfur and nitrogen co-doped coal-based hard carbon material, and carrying out secondary carbonization treatment on the product to prepare the soft carbon coated sulfur and nitrogen co-doped coal-based hard carbon material, a sodium ion battery based on the soft carbon coated sulfur-nitrogen co-doped coal-based hard carbon material has high sodium storage specific capacity and first coulombic efficiency and high potential platform area sodium storage capacity proportion.

The present invention discloses a hard carbon negative electrode material and a preparation method and application thereof. The base of the hard carbon negative electrode material is prepared with starch as raw material; the diameter of the internal pores of the hard carbon negative electrode material is larger than the diameter of the surface pores. The reasonable pore diameter and large interlayer spacing of the hard carbon negative electrode material are conducive to the insertion / extraction of sodium ions.

The application belongs to the technical field of battery materials, and particularly relates to a Prussian blue-like nano positive electrode material, a preparation method thereof and a sodium ion battery. x M y [Fe(CN)6] z , wherein M is a transition metal element, and 0

The invention discloses a bamboo-based derived nitrogen-doped hard carbon negative electrode material and a preparation method and application thereof.The preparation method creatively utilizes the characteristic that bamboo wood is rich in natural phenolic hydroxyl groups and comprises the steps that bamboo powder and an aldehyde group compound are subjected to in-situ phenol-aldehyde polycondensation under the alkaline condition, and a cross-linked network precursor is constructed; then adjusting the pH to weak acidity, and carrying out in-situ amination doping with a nitrogen-containing compound; and finally, carbonizing to obtain the nitrogen-doped hard carbon material. According to the method, structural reconstruction and uniform nitrogen doping of the bamboo-based precursor are synchronously realized through two-step continuous molecular-level reaction of'alkaline polycondensation-acidic amination '. When the obtained material is used as a sodium ion battery negative electrode, high reversible specific capacity (greater than 304 mAh / g), high first coulombic efficiency (greater than 92%) and excellent cycling stability (300-week capacity retention rate at 0.5 C is greater than 92%) are shown. The method is simple in process, green, low in cost and suitable for large-scale production.

The present invention relates to the field of sodium ion battery electrode materials, specifically a selenium-induced defect copper-based sulfur / selenide material and its preparation method and application, and a novel copper-based metal organic framework compound Cys-Cu precursor is preferentially prepared by a coprecipitation strategy; the precursor and a selenium source are then pyrolyzed and selenized under an inert atmosphere, and then naturally cooled to room temperature to obtain a product. The preparation method makes full use of the advantages of heteroatoms such as S / N in the ligand in the precursor, and a copper-based sulfur-selenide composite material with rich vacancies is obtained only by the preparation and selenization of the precursor, and the manufacturing process is simple and efficient, the cycle is short, and the stability is good. The composite material obtained by the method contains rich cation vacancies and a heterogeneous interface spontaneously constructed by copper-based sulfide and selenide, which can not only improve the material conductivity, promote effective electron / ion transport, but also create more sodium storage active sites, and further improve the material sodium storage capacity and structural stability.

The invention discloses a preparation method of a capacity type sodium ion battery hard carbon negative electrode material, which comprises the following steps: S1, raw material pretreatment: crushing, sieving and drying a hard carbon raw material to obtain a precursor raw material; s2, raw material impregnation: impregnating the precursor raw material obtained in the step S1 in a vacuum impregnation tank to obtain an impregnated raw material; s3, low-temperature carbonization: carrying out low-temperature carbonization on the impregnated raw material in a protective atmosphere to obtain a low-temperature carbonized material; s4, crushing and refining: crushing and refining the low-temperature carbonized material obtained in the step S3 to obtain a refined low-temperature carbonized material; and S5, performing high-temperature carbonization: performing high-temperature carbonization on the refined low-temperature carbonized material obtained in the step S4 in a protective atmosphere to obtain a finished product of the hard carbon negative electrode material. The preparation method of the hard carbon negative electrode material of the capacity type sodium-ion battery has the characteristics of low cost, high capacity and good graphitization degree.

The invention relates to the technical field of electrochemical materials, in particular to a pre-sodium hard carbon material and a preparation method and application thereof. The pre-sodium modification method for preparing the pre-sodium modification hard carbon material comprises the following steps: (1) mixing a carbon source, amino acid and phosphoric acid, and carrying out pre-carbonization reaction to obtain a doped carbon source; (2) providing dispersion liquid containing the doped carbon source, a surfactant and weak base, and introducing organic sodium salt to carry out sodium pre-modification reaction to obtain a hard carbon precursor; and (3) carrying out carbonization reaction on the hard carbon precursor to obtain the pre-sodium hard carbon material. The pre-sodium treatment method is simple to operate and high in safety, the obtained pre-sodium treatment hard carbon material is excellent in performance, and the problems that a sodium ion battery is low in energy density and poor in cycle performance can be effectively solved.

The application discloses a preparation method of a closed micropore structure sodium ion battery negative electrode hard carbon material, and comprises the following steps: S1, preparation of a precursor mixed solution: biomass raw material powder and an inorganic acid pore former are used to prepare the precursor mixed solution; S2, carbon precursor drying: the precursor mixed solution is dried to prepare the carbon precursor; S3, pore forming of a closed pore carbon intermediate: the carbon precursor is subjected to high-temperature activation reaction to obtain the closed pore carbon intermediate with a micropore structure after activation; S4, closed pore carbon intermediate refining treatment: the carbon intermediate is crushed and refined, and the refined closed pore carbon intermediate is obtained through sieving; and S5, high-temperature carbonization of the hard carbon material: the refined carbon intermediate obtained in the step S4 is subjected to high-temperature carbonization to obtain the hard carbon material with the closed micropore structure. The application has the characteristics of a green and environment-friendly process, a small specific surface area and excellent electrochemical performance.

The present invention provides a hard carbon material, wherein the hard carbon material has a central portion and a surface layer; the graphitization degree of the hard carbon material gradually increases from the central portion to the surface layer. Compared with the prior art, the present invention can increase the sodium storage capacity of the hard carbon material by controlling the graphitization degree of the hard carbon material, and the local graphitization of the hard carbon material can provide more sodium storage sites, thereby improving the energy storage performance of the sodium ion battery.

The invention discloses a preparation method of a hard carbon negative electrode material of a high-capacity sodium-ion battery. The preparation method comprises the following steps: S1, raw material mixing: mixing a crushed biomass raw material with an additive; s2, preparation of a precursor: carrying out low-temperature carbonization on the raw materials in a protective atmosphere; s3, preparation of a first-fineness precursor: carrying out coarse grinding on the precursor to obtain the first-fineness precursor; s4, precursor purification: carrying out acid pickling purification, centrifugation and water washing on the precursor with the first fineness to obtain a purified precursor; s5, preparation of a second-fineness precursor: carrying out wet mixing on the purified precursor, a coating agent and a cross-linking agent, and carrying out temperature-controlled secondary sanding to obtain second-fineness precursor slurry; s6, spray drying: carrying out spray drying on the second precursor slurry to obtain a coated precursor; and S7, high-temperature sintering: carrying out high-temperature carbonization on the coated precursor under protection to obtain the high-capacity hard carbon negative electrode material. The preparation method has the characteristics of high production efficiency, high capacity and high first-cycle charge-discharge efficiency.

The present invention provides a method for enhancing the hardness of carbon materials, comprising the following steps: a) placing a thermosetting polymer in a pure oxygen atmosphere in a low temperature and high pressure environment to obtain an oxygen-saturated thermosetting polymer; b) placing the device used in a) in a plasma excitation chamber, applying a high voltage and high frequency electric field while pumping the device used in a) to a low pressure atmosphere to obtain an oxidized thermosetting polymer; c) placing the oxidized thermosetting polymer obtained in b) in a catalyst solution, soaking and drying, pre-carbonizing under a protective atmosphere, acid washing and water washing to remove impurities and drying; d) taking the pre-carbonized product obtained in c) and carbonizing it at a higher temperature for a second time, cooling it, and obtaining a high-hardness carbon material. The present invention enhances the number of oxygen-containing functional groups of the thermosetting polymer precursor by combining the bulk adsorption of oxygen with the oxidation of high voltage plasma; and using a catalyst to fully crosslink aromatic molecules during carbonization to enhance the hardness of the prepared carbon material.

The invention discloses a sodium ion battery negative electrode material as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, preparing a Sb2S3 nanorod; and S2, uniformly dispersing the Sb2S3 nanorod in an aqueous dispersion of a carbon source, adding molybdate into the aqueous dispersion, then slowly adding a selenium-containing solution into the aqueous dispersion, carrying out a hydrothermal reaction, and calcining to prepare the sodium-ion battery negative electrode material with the composition of Sb2S3 / MoSe2 / C. The invention also discloses a preparation method of the sodium-ion battery negative electrode material with the composition of Sb2S3 / MoSe2 / C. The Sb2S3 nanorod is taken as a precursor or a template, the Sb2S3 / MoSe2 heterostructure material with a unique multi-stage layered rod-shaped structure is prepared by adopting methods such as nanostructure design, carbon material compounding and heterostructure construction, and the Sb2S3 / MoSe2 heterostructure material has excellent cycle performance and rate capability as a sodium-ion battery negative electrode material; the development of the sodium ion battery can be further promoted.