98 results about "Lithium ion battery anode" patented technology

The application relates to the technical field of lithium ion battery negative electrode materials, and discloses a graphitized porous silicon-carbon negative electrode material, a preparation method thereof and a lithium ion battery. The silicon-carbon negative electrode material comprises a core and a carbon coating layer coated on the outer surface of the core, and is characterized in that the core comprises an inner layer and a superficial layer from inside to outside, the silicon-carbon negative electrode material has gradiently distributed pores in the inside, and the porosity decreases from inside to outside along the inner layer, the superficial layer and the carbon coating layer; and the core comprises a silicon-carbon composite, the silicon-carbon composite comprises nano silicon particles, a conductive agent and graphitized carbon material. The graphitized silicon-carbon negative electrode material can solve the problems of easy cracking and rate reduction of the porous structure.

The application relates to a high-capacity porous niobium pentoxide material and a preparation method and application thereof, relates to niobium pentoxide and preparation and application thereof, and aims to solve the technical problems of low conductivity and slow ion diffusion of existing orthogonal phase niobium pentoxide materials. The material is formed by interconnection of 100-300 nm niobium pentoxide matrix nanoparticles, growth of 10-30 nm secondary nanoparticles on the surface, and a 'raspberry-like' multi-level assembly morphology; the material has a pore diameter of 2-20 nm, a specific surface area of 15-45 m 2 / g; and has an orthogonal phase niobium pentoxide structure and carbon doping characteristics. The material is prepared by using a surfactant containing a quaternary ammonium cation as a soft template, utilizing electrostatic-coordination synergistic action to drive niobium salt and organic quaternary ammonium cation assembly, and high-temperature sintering in an inert atmosphere. When used as a negative electrode of a lithium ion battery, the material reaches a capacity of 350 mAh / g at a current density of 0.1 A / g, and can be used in the field of fast-charging type alkali metal ion batteries.

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

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

The application provides a porous silicon-based composite material and a preparation method thereof and a lithium ion battery, and relates to the technical field of lithium ion battery negative materials.The porous silicon-based composite material has a honeycomb structure and is composed of porous silicon blocks, metal skeletons and carbon-based films.The porous silicon blocks are primary particles, the secondary particles are constructed by the metal skeletons, and the carbon-based films are coated on the surfaces of the porous silicon blocks and the metal skeletons.The porous silicon-based composite material can be denoted as Si / M@C.The metal skeleton M has strong rigidity and is used for supporting the porous silicon blocks, also serving as a conductive network and playing a limiting role.The carbon-based film C has elastic properties and is used as an artificial SEI film and for eliminating internal stress generated by volume expansion during charging, thereby protecting the main material.The porous silicon-based composite material has strong mechanical binding and limiting effects, stable interface properties and an optimized conductive network and ion transmission path.

This invention relates to an aqueous binder for lithium-ion battery negative electrodes, its preparation method, and its application. The raw materials for the aqueous binder include unsaturated carboxylic acid monomers, unsaturated nitrile monomers, unsaturated amide monomers, acrylate monomers, and functional monomers. The functional monomers include at least one selected from hydroxyethyl acrylate, hydroxyethyl methacrylate, methoxy polyethylene glycol acrylate, allyl polyethylene glycol, and allyl polyethylene glycol monomethyl ether. The aqueous binder of this invention incorporates acrylate monomers and functional monomers, which can lower the glass transition temperature of the copolymer while maintaining high peel strength. By introducing functional monomers with long side chains, the double-layer mechanism of polyacrylic acid itself and the steric hindrance effect of the long side bonds of the functional monomers are utilized as dispersants to achieve stable dispersion of the negative electrode slurry particles. The precipitation polymerization method can significantly reduce the internal resistance of lithium-ion batteries and improve peel strength.

The application belongs to the technical field of lithium ion battery negative electrode materials, and particularly relates to a MXene two-dimensional material, a graphite negative electrode material and a preparation method of the MXene two-dimensional material, the preparation method of the MXene two-dimensional material being as follows: lithium sulfate solution is added into a MXene dispersion liquid, stirred uniformly, vacuum dried, calcined at 300-500 DEG C, and the MXene two-dimensional material is obtained; and the application can effectively improve lithium ion conductivity and improve the performance of a battery.

This invention discloses a composite material of carbon-supported silicon nanodots derived from a hierarchical porous metal-organic framework (MOF), relating to the field of lithium-ion battery anode materials. The invention includes preparing a hierarchical porous MOF precursor with both micropores and mesopores; converting the precursor into a hierarchical porous carbon framework through controlled heat treatment; confining the growth of silicon nanodots within the mesopores of the carbon framework via vapor deposition; and removing residual metals by acid washing to obtain a purified target composite material. By using a MOF with a hierarchical porous structure as a precursor and combining it with vapor deposition technology, this invention enables the in-situ construction of uniformly dispersed silicon nanodots within the mesopores of the derived carbon framework, while simultaneously maintaining an efficient ion transport network using a microporous system.

This invention discloses a low-resistivity silicon suboxide lithium-ion battery anode material and its preparation method. Fluorinated silicon suboxide is mixed with a carbon precursor and a solvent, ground until dry, and the solvent is removed to obtain an intermediate material. The intermediate material is then calcined in a protective gas atmosphere using gradient heating and / or gradient pressurization to obtain the anode material. This invention constructs a fluorine gradient hole structure, which preferentially transforms into a stable LiF-rich solid electrolyte interphase (SEI) film during electrochemical cycling, significantly reducing the lithium-ion diffusion barrier and interfacial charge transfer impedance. The gradient heating and / or pressurization sintering process carbonizes the carbon precursor in situ on the surface of the fluorinated layer, forming a dense and robust coating layer. This coating layer forms a strong interfacial bond through vacancy bonding and mechanical interlocking, buffering volume expansion. The anode material obtained using this invention exhibits excellent electrochemical performance and significantly reduces impedance.

The present application relates to a kind of evaluation methods of the cohesion of lithium ion battery negative electrode sheet, comprising the following steps: (1) the preparation of negative electrode sheet: after roller pressing, negative electrode sheet is cut into certain size, and weighed;(2) the preparation of separator: take single-side rubber-coated separator, cut 6 same size;(3) the preparation of sample: negative electrode sheet is in the middle, and separator upper and lower layers cover negative electrode sheet;(4) three times hot pressing: after three times hot pressing, the mass ratio of negative electrode sheet reduction is calculated;(5) evaluation analysis: according to the size relationship of the mass ratio of different negative electrode sheet reduction, to evaluate their cohesion size relationship.The present application can greatly reduce the test volatility caused by human factors, improve the stability and accuracy of test, and the method is simple and easy to operate, and does not increase additional cost.

This invention relates to the field of battery technology, and in particular to a lithium-ion battery anode, its preparation method, and a lithium-ion battery. The invention provides a method for preparing a lithium-ion battery anode, comprising the following steps: stacking a first composite layer and a second composite layer with the surface of an intermediate metal layer in contact with the surface of a lithium metal layer, and then pressing them to obtain a lithium-ion battery anode; wherein the first composite layer comprises a silicon-based anode layer and an intermediate metal layer; and the second composite layer comprises a lithium metal layer and a conductive substrate. The method for preparing the lithium-ion battery anode of this invention solves the problems of volume expansion of silicon anodes, dendrite growth of lithium metal anodes, and poor process safety when simply combining silicon anodes with lithium metal.

This invention relates to the field of carbon composite materials, specifically providing a MOF-pitch-based porous carbon composite material, its preparation method, and its applications. The preparation method includes the following steps: doping a transition metal oxide and a nitrogen source into a MOF material to obtain a MOF precursor; mixing the MOF precursor with an amine crosslinking agent and oxidized pitch, followed by pre-carbonization and activation to obtain pitch-based porous carbon; and fluorinating the pitch-based porous carbon to obtain the MOF-pitch-based porous carbon composite material. The MOF-pitch-based porous carbon composite material prepared by this method possesses high pore volume, high crush strength, and high initial efficiency, exhibiting excellent electrochemical and electrical properties when used as a negative electrode material for lithium-ion batteries.

This invention belongs to the technical field of lithium-ion battery anode materials, specifically relating to a silicon-carbon anode material and its preparation method. The silicon-carbon anode material comprises a porous carbon matrix, silicon particles, and a coated carbon layer, wherein the coated carbon layer coats the porous carbon matrix, and the silicon particles are deposited within the pores of the porous carbon matrix; the porous carbon matrix consists of a hard carbon core and a soft carbon shell, the soft carbon shell containing a conductive agent. This invention, through a multi-layer structure design, solves the technical problems of large volume expansion and poor cycle performance of traditional silicon-based anodes during charge and discharge.

This invention discloses a negative electrode sheet, its preparation method, and a lithium-ion battery. The negative electrode sheet includes a negative current collector, a first active coating, and a second active coating. The first active coating is located between the negative current collector and the second active coating. The porosity of the second active coating is greater than that of the first active coating. The pores in the second active coating are created by volatilizing volatile solid additives under gradient heating conditions. The volatile solid additives include at least one of 1,8-dichloronaphthalene, 3,5-dichlorobromobenzene, and 1,4-dibromo-2,5-difluorobenzene. The gradient heating includes first gradient heating and then gradient cooling. By using volatile solid additives to create pores through gradient heating and then gradient cooling, this invention provides a negative electrode sheet that balances high areal density and high compaction density, thereby improving the capacity utilization, energy density, and cycle performance of the positive electrode.

The present application relates to the technical field of lithium battery negative electrode material binder preparation, more particularly to a lithium ion battery negative electrode binder and negative electrode sheet based on in-situ cross-linking esterification.The present application mixes polyacrylic acid binder, cyclodextrin-based material and catalyst, and disperses them in a solvent to prepare a premixed binder; the premixed binder is mixed with a silicon-based negative electrode active material and a conductive agent, and is coated on the surface of a current collector, and the solvent is dried; during the drying process, the carboxyl groups of the polyacrylic acid binder and the hydroxyl groups of the cyclodextrin-based material undergo in-situ cross-linking esterification under the catalysis of the catalyst, forming a three-dimensionally cross-linked bonding network.This strong bonding network can effectively alleviate the swelling effect of the silicon-based negative electrode sheet during the cycling process, endowing the electrode with excellent structural stability, and in combination with the internal cavity structure of the cyclodextrin-based material, can provide additional diffusion channels for lithium ions, improving the rate performance of the battery.

This application provides a negative electrode sheet, its preparation method, a lithium-ion battery, and an electronic device. The negative electrode sheet includes a negative current collector and a negative active material layer disposed on at least one side of the negative current collector. The negative active material layer contains silicon-based particles. The mass percentage of silicon-based particles in the negative active material layer continuously increases in the direction from the negative current collector to the surface of the negative electrode sheet. Furthermore, the mass percentage of silicon-based particles at any point in the negative active material layer satisfies the relationship between the distance from that point to the negative current collector. The negative active material layer of the negative electrode sheet of this application is a complete layer without any interface with abrupt changes in composition, which can reduce the risk of film delamination of the negative electrode sheet of the lithium-ion battery and improve the lifespan of the lithium-ion battery.

The present application relates to a kind of binder for lithium ion battery negative electrode and its preparation method and application.The binder includes polyacrylamide as rigid component and aqueous polyurethane as flexible component, the polyacrylamide is combined with the aqueous polyurethane by intermolecular interaction and forms three-dimensional network structure.Compared with prior art, the binder obtained by the present application can effectively inhibit the volume expansion of silicon-based negative electrode while having excellent interfacial adhesion and electrochemical stability.

The application discloses a modified lithium ion battery negative electrode material and a preparation method and application thereof, and relates to the technical field of battery materials.The preparation method disclosed by the application comprises the following steps: S1: polyvinylidene fluoride is dissolved in NMP, after stirring and dissolving, acetylene black and an active material are continuously added, and stirring is uniformly conducted to obtain a slurry; S2: the slurry is coated on the surface of a copper foil, vacuum drying is conducted, and a coated copper foil is obtained; and S3: the coated copper foil is punched to obtain a negative electrode material.The lithium ion battery negative electrode material prepared by the application has good conductivity and excellent rate performance, can meet the requirements of the industry, and has a good application prospect.

The application provides a method for preparing a carbon-based negative electrode material for a lithium ion battery by using cyanamide waste residue and application, and the method comprises the following steps: dispersing and dissolving cyanamide waste residue and a carbon source in an ethanol solution in proportion and mixing thoroughly; then, the mixed solution is dried to remove ethanol, calcium carbonate in the cyanamide waste residue is used as a structure directing agent, the carbon source is used as a carbonization precursor, and carbonization is completed through calcination; finally, the calcination product is subjected to acid extraction treatment through a hydrochloric acid-hydrofluoric acid mixed acid solution, and is washed with water until neutral, so that a composite carbon material of waste residue carbon coupling nanometer ring-shaped microcrystalline carbon, i.e., a carbon-based negative electrode material for a lithium ion battery, is obtained. The application also provides application of the carbon-based negative electrode material in a lithium ion battery. The application realizes resourceization and high-value treatment of solid waste by efficiently utilizing cyanamide waste residue, and the obtained carbon-based negative electrode material has the advantages of high performance, low cost and the like, has environmental benefits and economic benefits, is suitable for a lithium ion battery negative electrode, and has a wide application prospect.

This invention discloses a silicon-carbon anode material with silicon nitride-doped hard carbon coating on silicon nanoparticles, its preparation method, anode sheet, and lithium-ion battery. It uses silicon nanoparticles as the core structure and utilizes silicon nitride-doped hard carbon to synergistically coat the silicon nanoparticles, solving the problems of weak interfacial bonding between the carbon coating layer and silicon nanoparticles, low mechanical strength, and inability to adapt to long-term volumetric cycling expansion. The prepared silicon-carbon anode material has advantages such as long cycle life, high initial efficiency, and good conductivity when used as a lithium-ion battery anode material.

The application discloses a kind of electrically conductive polymer coated antimony selenide / ordered mesoporous carbon composite negative electrode material and its preparation method and application, belong to lithium ion battery negative electrode material preparation technical field.Ordered mesoporous carbon is added in antimony selenide precursor liquid and is mixed uniformly, and precursor mixed solution is obtained;The precursor mixed solution is kept at 180 DEG C for 24 h, and is cooled to room temperature, and the precipitate is collected by centrifugation, washing, freeze-drying, in inert atmosphere, with 3 DEG C / min heating rate to 500 DEG C, annealing, and Sb2Se3@OMC composite material is obtained;Ammonium persulfate and Sb2Se3@OMC composite material are added to the mixed solution of 3,4-ethylenedioxythiophene and dilute hydrochloric acid and are mixed uniformly, and are dried, to obtain electrically conductive polymer coated antimony selenide / ordered mesoporous carbon composite negative electrode material.In the electrode made of the composite material, antimony selenide nanoparticles are uniformly distributed in ordered mesoporous carbon and surface, and are finally coated by electrically conductive polymer, and have excellent long cycle stability and rate performance when used as lithium ion battery negative electrode.

A negative electrode current collecting disc (100) and a cylindrical lithium ion battery. The negative electrode current collecting disc (100) comprises a disc body (110) and a plurality of flanges (120) protruding from one side of the outer periphery of the disc body (110), wherein the plurality of flanges (120) are used for fitting flush to and connecting with the wall of a casing (820) of the cylindrical lithium ion battery. The edge of the negative electrode current collecting disc (100) is further provided with first stress release notches (130); each first stress release notch (130) is formed by the edge of the disc body (110) and the edge of the corresponding flange (120) together recessing inwards in a junction area therebetween; and the first stress release notches (130) enable the flanges (120) to be bent relative to the disc body (110) along the first stress release notches (130). By providing the first stress relief notches (130), problems such as deformation, warping, and weld joint fracture of negative electrode current collecting discs caused by grooving processes are solved.

This invention discloses a high specific surface area mesoporous tin oxide powder and its preparation method. The method includes: dissolving a tin source in a mixed solvent of alcohol and deionized water, adding a ketone complexing agent and a nonionic dispersant, and stirring to form a tin-based complex precursor solution; then transferring the solution to a hydrothermal reactor for hydrothermal aging treatment, causing the precursor solution to hydrolyze and condense, forming gel particles in situ; after solid-liquid separation, washing with alternating anhydrous ethanol and dilute ammonia water, and drying to obtain the precursor powder; finally, performing staged heating calcination under an air-nitrogen mixed atmosphere, first removing organic components at low temperature, and then completing the crystal phase transformation at high temperature to obtain rutile phase SnO2 powder. The powder has an average particle size of 8–15 nm and a specific surface area of ​​85–110 m² / g. 2 The powder has a pergola size of 3–6 nm and good dispersibility. This invention effectively suppresses grain agglomeration through complexation regulation, hydrothermal-sol-gel coupling, and gradient atmosphere calcination. The prepared powder is suitable for applications such as gas sensors, lithium-ion battery anodes, or transparent conductive films.

The application discloses a silicon-based negative electrode material with a layered structure and a preparation method and application thereof, and belongs to the field of lithium ion battery negative electrode materials. The material comprises an active core, a LiF intermediate layer and a carbon shell coating layer; the active core comprises nano silicon particles; the LiF intermediate layer is a continuous dense layer obtained by in-situ growth on the surface of the nano silicon particles; and the carbon shell coating layer is a porous graphitized carbon coating layer. The material is formed by cold pressing and segmented heat treatment in-situ reaction, and the interfaces obtained are tightly combined and not easy to fall off and peel off. When the silicon-based negative electrode material is applied to the preparation of a lithium ion battery, stable electrode interfaces, fast ion transmission rate and excellent anti-expansion capacity provided by the negative electrode material can effectively improve the initial coulomb efficiency of the battery, the long cycle capacity retention rate under high rate and the high rate reversible capacity.

The application relates to the technical field of lithium ion battery negative electrode materials, and discloses a silicon-carbon negative electrode material, a preparation method thereof and a lithium ion battery, wherein the preparation method comprises the following steps: (1) mixing an oxidized graphene dispersion liquid with an alkali, adjusting the pH to 8-12 to obtain an oxidized graphene slurry; (2) mixing the oxidized graphene slurry, silicon powder and graphite, and then drying to obtain a precursor; taking the total amount of the oxidized graphene, the silicon powder and the graphite as a reference, the content of the oxidized graphene is 0.1-5 wt%, the content of the silicon powder is 20-65 wt%, and the content of the graphite is 35-75 wt%; (3) performing heat treatment on the precursor under an inert atmosphere. The silicon-carbon negative electrode prepared by the preparation method has obvious excellent cycle stability while maintaining a relatively high capacity.

This invention discloses a battery anode adhesive with a topological structure, its preparation method, and its application, belonging to the field of lithium-ion battery technology. The adhesive is prepared by bridging a hyperbranched polyamide intermediate with a carbonyl-containing copolymer through a nucleophilic addition-elimination reaction, forming a three-dimensional network with a topological structure. The adhesive prepared by this invention is water-soluble and can effectively disperse the anode material of lithium-ion batteries. Its topological structure, combined with multidimensional hydrogen bonds, tightly binds to the lithium-ion battery anode material, significantly improving the stability and cycle performance of lithium-ion batteries. After 500 charge-discharge cycles at 1C rate, the optimal capacity retention rate of the lithium-ion battery can still be maintained above 86%.

The application provides a preparation method of one-dimensional Nb2O5 nanorod material and belongs to the technical field of nanometer materials. The method comprises the following steps: uniformly dispersing a niobium source in anhydrous ethanol to obtain a turbid solution; uniformly dispersing oleic acid in the turbid solution to obtain reaction liquid 1; performing a solvothermal reaction on the reaction liquid 1, collecting a solid product; and calcining the solid product to obtain the one-dimensional Nb2O5 nanorod material. The one-dimensional Nb2O5 nanorod material is precisely synthesized for the first time under the synergistic regulation of an anhydrous ethanol and an oleic acid double-solvent system, and the one-dimensional Nb2O5 nanorod material has excellent cycle stability as a lithium ion battery negative electrode material.

This invention relates to a micro-oxidized artificial graphite lithium-ion battery anode material and its preparation method. The preparation method includes the following steps: 1) Surface coating treatment of raw materials to prepare secondary granular artificial graphite, followed by carbonization in a tube furnace. 2) After carbonization, cooling to 300-900℃, and continuously introducing oxygen for oxidation reaction. The oxygen flow rate during oxidation reaction is 0.2-3 L / min, and the oxidation reaction time is 1-60 min. 3) After oxidation reaction, oxygen introduction is stopped, and after cooling, post-processing is performed to obtain the lithium-ion battery anode material. This invention uses a gas-phase oxidation method to etch the artificial graphite material, which can destroy and peel off the dense structure of the artificial graphite, resulting in significant changes in key indicators such as increased specific surface area and powder compaction density, and significantly improved electrochemical performance.