25results about How to "Improve lithium storage performance" patented technology

The invention provides a B / N co-doped high-graphitization-degree artificial graphite negative electrode material and a preparation method thereof, and the preparation method of the artificial graphite negative electrode material comprises the following steps: crushing raw material coke to obtain primary particles, and then mixing, granulating and shaping to obtain secondary particles; fully mixing the obtained secondary particles with an organic nitrogen source, and then pre-carbonizing to obtain a nitrogen-doped precursor; and fully mixing the obtained nitrogen-doped precursor with an organic boron source, and then carrying out secondary carbonization, shaping and graphitization to obtain the B / N co-doped high-graphitization-degree artificial graphite negative electrode material. The artificial graphite negative electrode material disclosed by the invention has high energy density and high rate performance, and meanwhile, the first efficiency can also be improved.

The invention provides a graphite composite material, a preparation method thereof and a secondary battery, and relates to the technical field of lithium ion battery negative electrode materials. The graphite composite material comprises an inner core and a shell layer, the inner core comprises metal element doped metal oxide and graphite, the metal element doped metal oxide is embedded between sheet layers of the graphite, the shell layer comprises multi-walled carbon nanotubes and amorphous carbon, and the multi-walled carbon nanotubes are distributed in the amorphous carbon in a 3D net shape. According to the invention, by introducing the doping element, the lithium intercalation active sites of the metal oxide are increased, so that the lithium storage performance of the graphite composite material is improved; through the construction of a core-shell and intercalation structure, the volume expansion of the metal oxide is inhibited, so that the cycling stability of the graphite composite material is improved.

The invention discloses a silicon monoxide-based negative electrode material and preparation and application thereof, and belongs to the technical field of lithium ion battery preparation, and the preparation method comprises the following steps: bombarding pure silicon monoxide powder by nitrous oxide plasma to form N-attached modified porous silicon monoxide powder; more lithium ions can be accommodated for intercalation and deintercalation due to the porosity, the volume effect of the material in the electrochemical reaction process can be relieved, so that the cycle life of the battery is prolonged, and meanwhile, the N element is doped in the generated carbon layer, so that the conductivity and the lithium storage capacity are improved; the two prepared coating layers form a compact carbon coating layer after high-temperature carbonization, the structural integrity of the silicon monoxide negative electrode material in the charging and discharging process is enhanced, the compact carbon coating layer can effectively relieve stress caused by volume change and reduce repeated generation and fracture of an SEI film in the embedding and de-embedding process of lithium ions, and the lithium ion battery has the advantages of being simple in preparation process, low in cost and high in reliability. The first coulombic efficiency is improved, and the capacity and performance stability of the battery can be maintained.

The invention discloses a high-load electrode material and a preparation method thereof, and the high-load electrode material is prepared by the following steps: reacting a modified monomer, 4, 4 ', 4'-triaminotriphenylamine and 3, 3 ', 4, 4'-biphenyl tetracarboxylic dianhydride to form polyamic acid, adding a modified filler, reacting amino on the modified filler with part of carboxyl on the polyamic acid, and carrying out high-temperature imidization treatment. The surface of the modified filler contains amino groups which can react with a polyamide acid molecular chain, the molecular chain is of a hyperbranched structure, so that the electrolytic material is an interlaced porous grid, the specific surface of the electrolytic material is increased, the modified filler internally contains a structure in which silicon and carbon support each other, and the surface of the modified filler is coated with organic polymers, so that collapse and expansion of the electrode material are prevented, and the service life of the electrode material is prolonged. The electrode material has the advantages that the electrode material contains metal oxide inside to form pseudocapacitance to increase the electricity storage capacity, the organic matter on the surface contains N = N bonds and S-S bonds to improve the lithium storage performance, and the capacity of the electrode material is further increased due to the addition of 4, 4 '4' '-triaminotriphenylamine and a large number of benzene ring structures.

The invention relates to a two-dimensional bimetal organic nanosheet loaded silicon-carbon composite material and a preparation method and application thereof, and belongs to the technical field of preparation of lithium ion power battery electrode materials.Firstly, dopamine is polymerized on the surface of silicon powder in situ, and the silicon-carbon composite material (Si-C) is obtained after high-temperature calcination; then, terephthalic acid, cobalt chloride hexahydrate, nickel chloride hexahydrate and Si-C are added into a mixed solution prepared from N, N-dimethylformamide, deionized water and ethyl alcohol; and after dissolving, injecting triethylamine and stirring, sealing the container after light gray precipitates appear, continuously performing ultrasonic treatment, performing centrifugal washing for multiple times, and drying at room temperature to obtain the product Si (at) C / Ni-Co-BDC composite material. Compared with pure silicon powder and silicon-carbon composite materials, the composite material Si (at) C / Ni-Co-BDC has better structural stability and rich redox active sites, the lithium storage performance of the material can be further optimized, and the composite material has better application prospects.

The invention discloses a long-circulation lithium iron phosphate battery and a preparation method thereof, a positive plate, a negative plate, a porous diaphragm and an electrolyte are assembled into the battery in a glove box filled with argon, and the long-circulation lithium iron phosphate battery is prepared. A negative plate is a long-circulation lithium iron phosphate battery prepared by mixing polyvinylidene fluoride, a negative electrode material and acetylene and loading the mixture on a copper foil, the negative electrode material contains silicon dioxide, so that the lithium storage performance of the negative electrode material is improved, and meanwhile, high-temperature carbonization treatment is performed, so that an organic framework forms a grid carbon layer to coat the surface of the silicon dioxide, and the lithium storage performance of the lithium iron phosphate battery is improved. The lithium iron phosphate battery negative electrode material prevents silicon dioxide in the negative electrode material from promoting volume expansion due to charging and discharging, so that the stability of the negative electrode material is ensured, the grid carbon layer increases the conductivity of the negative electrode material, and the negative electrode material is integrally coated with the carbon layer, so that the expansion of the negative electrode material is limited, and the service life of the lithium iron phosphate battery is prolonged.

This invention provides an aluminum foil anode material for lithium-ion batteries and its preparation method. The method applies metallic aluminum to a monolithic material system. Based on a chemical displacement reaction, a rolling-heat treatment method is used to dope the target metal element into the aluminum foil composite material, achieving alloy composition design of the aluminum foil. Furthermore, carbon elements can be incorporated into the interlayer of the aluminum foil to improve the lithium storage performance of the aluminum foil anode. The preparation method of this invention is simple and feasible, with a simple process flow and low cost. It can modify a large quantity of aluminum foil in a short time, and the reaction raw materials can react completely, with useless reaction products volatilizing spontaneously. In addition, the modified aluminum foil material can be directly used as a lithium-ion battery anode material, effectively improving the lithium storage performance of the aluminum foil anode material.

The invention discloses a method for preparing a negative electrode material for a lithium ion battery, which belongs to the technical field of lithium ion batteries and comprises the following steps: mixing LiF with hydrochloric acid and heating the mixture, and then adding Ti into the solution. 3 AlC 2 After the material is mixed, it is magnetically stirred to obtain a mixed solution. The mixed solution is centrifuged and washed, and LiCl solution is added. After standing, it is centrifuged again. After the centrifugation is completed, the lower layer of precipitation is taken out, and the sample is freeze-dried to obtain a sample MXene powder. The prepared sample MXene powder is stirred with water, and then BiCl is added. 3 The test solution was stirred continuously, and after being mixed evenly, it was filtered to form a film, and after drying, a MXene composite film was obtained. The MXene composite film was placed in NaBH 4 The solution is reacted, and after the reaction, the MXene / Bi composite material is obtained by drying. 3 and NaBH 4 The reaction displaces Bi nanoparticles distributed on the surface of MXene nanosheets, forming a relatively stable three-dimensional structure, which provides more attachment sites for Li storage. The presence of Bi improves the lithium storage performance of MXene.

The present invention relates to the technical field of lithium ion battery recycling, and more specifically, to a high-efficiency impurity removal and recycling process for lithium ion batteries. The process comprises the following steps: preparation of a high-efficiency leaching agent; grading of lithium batteries; pretreatment of negative electrode plates; and recycling of plate materials. The present invention can simultaneously achieve leaching of lithium iron phosphate and regenerate graphite black powder while leaching metal ions by preparing a high-efficiency leaching agent. 2+ is oxidized to Fe 3+ , and precipitates into iron hydroxide when sodium carbonate solution is added later, while lactic acid in the high-efficiency leaching agent leaches nickel, cobalt, manganese and lithium cobalt oxide positive electrode materials. The process is simple and can recycle a variety of waste lithium battery components at the same time, with high recycling efficiency, good leaching effect of various metal components and high leaching rate.

The present invention relates to the field of new energy batteries, and in particular, to a negative electrode plate, a preparation method thereof, and a battery, wherein the negative electrode plate comprises a current collector and a negative electrode active material layer disposed on the surface of the current collector, wherein the negative electrode active material layer comprises a negative electrode composite material; wherein the negative electrode composite material comprises graphite particles and a coating layer coated on the surface of the graphite particles; wherein the coating layer comprises graphene and nanosheets containing metal elements; the graphene has a mesh structure, and the mesh structure covers the outer surface of the graphite particles; the nanosheets containing metal elements are at least partially embedded in the grid of the mesh structure and contact the surface of the graphite particles. The negative electrode plate of the present invention is applied to lithium-ion batteries, which can significantly improve the specific capacity and cycle stability of lithium-ion batteries.

The invention discloses a silicon oxide-based negative electrode material and its preparation and application, belonging to the technical field of lithium ion battery preparation, comprising the following steps: nitrous oxide plasma bombards pure silicon oxide powder to form modified porous silicon oxide powder with N attached, wherein the porosity can accommodate more lithium ions for embedding and de-embedding, and also helps to alleviate the volume effect of the material in the electrochemical reaction process, thereby extending the cycle life of the battery, and at the same time, the N element is doped in the generated carbon layer, thereby improving the conductivity and lithium storage capacity; the two coating layers prepared by the invention form a dense carbon coating layer after high-temperature carbonization, thereby enhancing the structural integrity of the silicon oxide negative electrode material in the charging and discharging process, and in the process of embedding and de-embedding of lithium ions, the dense carbon coating layer can effectively alleviate the stress caused by volume change and reduce the repeated generation and rupture of SEI film, thereby improving the initial coulomb efficiency and helping to maintain the capacity and performance stability of the battery.

The present invention discloses a carbon fiber material, a preparation method thereof and a lithium ion battery. The carbon fiber material comprises graphitized carbon fibers, the graphitized carbon fibers are overlapped to form a porous network structure, and the graphitized carbon fibers have micropores on their surface. The carbon fiber material of the present invention has a porous network structure, and there are many nanostructure gaps formed by the interlacing of carbon fibers between the carbon fibers, which is very beneficial for the diffusion of electrolytes and the deintercalation of lithium ions, and is beneficial for improving the specific surface area and lithium storage performance of the material. At the same time, the graphitized carbon fibers have better electrical conductivity than ordinary carbon fibers, and the micropores on the surface of the graphitized carbon fibers are beneficial for the storage of lithium adsorbed ions on the surface and edges of the carbon fibers, thereby increasing the capacity. The carbon fiber material of the present invention is applied to lithium ion batteries, which can significantly improve the performance of the batteries.

This invention relates to a porous carbon material with a hierarchical distribution, its preparation method, and its application. The pores of the porous carbon material include: a first micropore (less than 10%), a second micropore (5%–15%), a first mesopore (15%–25%), a second mesopore (50%–70%), a third mesopore (1%–10%), and a fourth mesopore (less than 1%). The first micropore has a pore size of less than 1 nm; the second micropore has a pore size of greater than or equal to 1 nm but less than 2 nm; the first mesopore has a pore size of greater than or equal to 2 nm but less than 4 nm; the second mesopore has a pore size of greater than or equal to 4 nm but less than 7 nm; the third mesopore has a pore size of greater than or equal to 7 nm but less than 10 nm; and the fourth mesopore has a pore size of greater than or equal to 10 nm but less than or equal to 50 nm. The silicon-carbon composite material prepared using this porous carbon material has a high amount of nano-silicon deposition and good uniformity. Applying the silicon-carbon composite material to lithium-ion batteries can improve the battery's initial efficiency and specific capacity.

The invention belongs to the technical field of battery materials, and discloses a coated silicon negative electrode material and a preparation method and application thereof. The coated silicon negative electrode material comprises silicon and a coating layer coating the silicon, and the coating layer comprises vanadium pentoxide. According to the invention, the interface problem of silicon and sulfide electrolyte is improved through vanadium pentoxide coating, and the electrical properties of silicon are improved. Vanadium pentoxide is used as an excellent lithium storage material, the surface of a silicon material is coated with the vanadium pentoxide as a coating material, the interface problem of silicon and sulfide electrolyte can be improved, deposition of lithium on the negative electrode side and generation of lithium dendrites are reduced, the rate capability is improved, the volume expansion of vanadium pentoxide is small in the lithium intercalation and deintercalation process, and vanadium pentoxide is coated on silicon, so that the lithium intercalation and deintercalation efficiency is improved. The method can inhibit the volume expansion of silicon, reduce the damage of the volume change in the silicon lithiation lithium removal process to the contact property of silicon and sulfide solid electrolyte, and improve the cycling stability and rate capability of the material, so that the silicon material can be better applied to the sulfide solid-state battery.

The invention provides a cobalt phosphide-porous carbon nanoflower composite material and a preparation method thereof, a lithium ion battery and electric equipment, and relates to the field of lithium ion batteries. The preparation method comprises the following steps: carrying out first mixing on cobalt salt, hexamethylenetetramine, water and ethylene glycol, and carrying out hydrothermal reaction to obtain cobalt hydroxide nanosheets; carrying out second mixing on the cobalt hydroxide nanosheets and sodium citrate, and carrying out first calcination on the obtained mixture in an inert atmosphere to obtain a first calcined product; and carrying out third mixing on the first calcined product and red phosphorus, and carrying out second calcining on the obtained mixture in an inert atmosphere to obtain the cobalt phosphide-porous carbon nanoflower composite material. Cobalt hydroxide nanosheets are prepared by adopting a simple hydrothermal method, then the cobalt hydroxide nanosheets are respectively calcined with sodium citrate and red phosphorus to prepare the cobalt phosphide-porous carbon nanoflower composite material, the prepared cobalt phosphide is small in particle size, the ion diffusion length can be shortened, and rapid transmission can be realized.

The invention discloses a germanium-regulated silicon / carbon fiber composite material and a preparation method and application thereof, and the preparation method of the Si / Ge CNFs composite material comprises the following steps: (1) adding a GeO2 / F127 dispersion liquid into a silicon nanoparticle / P123 dispersion liquid, and stirring to obtain a silicon / germanium precursor dispersion liquid; (2) dissolving PVA in the silicon / germanium precursor dispersion liquid, and preparing a uniformly dispersed GeO2 / Si PVA fiber composite material through an electrostatic spinning technology; and (3) carrying out heat treatment on the GeO2 / Si-coated PVA fiber composite material in a hydrogen-argon mixed gas atmosphere to reduce GeO2 into Ge nanoparticles and convert PVA fibers into carbon fibers so as to obtain the Ge / Si-coated CNFs composite material. The initial reaction potentials of silicon and germanium in the Ge / Si-coated CNFs composite material are different, stress caused by volume change is effectively released, the carbon fibers can relieve volume expansion of silicon and germanium, the transfer rate of Li < + > and electrons in the lithiation process is increased, and the lithium storage performance of the Ge / Si-coated CNFs composite material is improved. The preparation method is economical, efficient, green and environment-friendly, and a simple and efficient method is provided for preparation of the germanium-silicon-carbon composite negative electrode.

The invention discloses a binder-free transition metal sulfide composite nitrogen-doped graphene negative electrode material and a preparation method thereof, and belongs to the technical field of secondary battery negative electrode materials. According to the technical scheme, the preparation method comprises the following steps: 1) dissolving zinc nitrate, cobalt nitrate and nitrogen-doped graphene in a mixed solution of ethanol and water, uniformly mixing, adding ammonium fluoride and urea, and continuously stirring; 2) adding foamed nickel and the uniformly mixed solution into a high-pressure reaction kettle for hydrothermal treatment, cooling, washing and drying to obtain a Zn-Co-precursor; (3) calcining the Zn-Co-precursor in an inert atmosphere, and (4) adding the Zn-Co-precursor into a high-pressure reaction kettle containing a sulfur source for hydrothermal vulcanization treatment, washing and drying to obtain the ZnCo2S4-coated NGr / NF negative electrode material.The graphene negative electrode material can improve the overall performance and stability of a secondary battery.

The invention provides a carbon-coated nano-silicon negative electrode material with doped elements distributed in a dispersed manner and a preparation method thereof. The nano-silicon negative electrode material comprises doped nano-silicon and a carbon coating layer coating the surface of the doped nano-silicon, in the doped nano silicon, doped elements are dispersed and distributed in the nano silicon. According to the carbon-coated nano-silicon negative electrode material with the doped elements distributed in the dispersed mode and the preparation method of the carbon-coated nano-silicon negative electrode material, the volume expansion of silicon is inhibited through element doping and carbon coating, and ultrahigh capacity and good cycling stability are obtained.

The invention provides a negative electrode material, a preparation method and a lithium ion battery. The negative electrode material comprises an active substance and a shell layer coating the surface of the active substance; the active substance comprises transition metal carbodiimide, and the shell layer comprises a conductive polymer; wherein the chemical formula of the transition metal carbodiimide is M [N (CN) 2] x; m is transition metal, and x is equal to 1-4. The negative electrode material provided by the invention uses an inorganic nitrogen-containing transition metal material as an active substance, contains a complex [N (CN) 2]-anion and has a layered structure, so that the negative electrode material has a relatively high specific surface area and a relatively high pore structure, and the capacity of a battery is improved; and on the other hand, the conductive polymer is used as a protective shell layer for coating the transition metal carbodiimide, so that rapid electron transmission on the surface of the negative electrode material is facilitated, electrochemical reaction kinetics of the material is promoted, and the material has excellent structural stability and lithium storage performance in the charge-discharge cycle process.

The invention relates to the field of new energy batteries, in particular to a negative pole piece, a preparation method thereof and a battery, the negative pole piece comprises a current collector and a negative active material layer arranged on the surface of the current collector, and the negative active material layer comprises a negative composite material; wherein the negative electrode composite material comprises graphite particles and a coating layer coating the surfaces of the graphite particles; wherein the coating layer comprises graphene and nanosheets containing metal elements; the graphene has a net-shaped structure, and the net-shaped structure covers the outer surfaces of the graphite particles; the nanosheets containing the metal elements are at least partially embedded into grids of the net-shaped structure and are in contact with the surfaces of the graphite particles. When the negative pole piece is applied to the lithium ion battery, the specific capacity and the cycling stability of the lithium ion battery can be remarkably improved.

The invention discloses a high-entropy sulfide negative electrode material, a lithium ion battery and preparation and application of the high-entropy sulfide negative electrode material and the lithium ion battery. The high-entropy sulfide is FeNiCoCuLiSx, x is 5.5-6.5, and the preparation method of the high-entropy sulfide comprises the following steps: adding nitrates of Fe, Ni, Co, Cu and Li into an organic solvent and a template agent glycerol according to a molar ratio of 1: 1: 1: 1: 1: 1, mixing and dissolving, reacting the obtained mixed solution at 150-170 DEG C, dispersing and centrifuging to obtain a precursor; and dispersing the precursor and thioacetamide in an organic solvent, reacting at 140-160 DEG C, and dispersing and centrifuging after the reaction to obtain the product high-entropy sulfide. The obtained high-entropy sulfide has excellent long cycle stability, high specific capacity and high-rate charge-discharge performance.

The invention discloses a PVP (Polyvinyl Pyrrolidone) coated carbohydrate-based hard carbon negative electrode material as well as a preparation method and application thereof. The preparation method comprises the following steps: dissolving carbohydrate in water to prepare a first solution, heating the first solution for gelatinization treatment, and freeze-drying to obtain carbohydrate powder; carrying out first heat treatment on the carbohydrate powder to obtain a pre-carbonized carbon material; adding the pre-carbonized carbon material into an acid solution for reaction, and drying a reaction product to obtain carbon powder; mixing carbon powder and a doping agent, and grinding to obtain a nitrogen-sulfur co-doped precursor; adding the nitrogen-sulfur co-doped precursor into a polyvinylpyrrolidone solution to react, and then drying to obtain a coated precursor; and carrying out heat treatment on the coated precursor to obtain the polyvinylpyrrolidone coated carbohydrate-based hard carbon negative electrode material. According to the invention, the pore structure integrity and functional coating effectiveness of the carbon material are synergistically realized, the lithium storage capacity, the first coulombic efficiency and the cycle life of the lithium ion battery are improved, and the application requirements of the high-performance electrode material of the lithium ion battery are met.

The invention relates to the technical field of lithium ion battery recovery, in particular to an efficient impurity removal and recovery process for a lithium ion battery. Comprising the following steps: preparing an efficient leaching agent; performing grading treatment on the lithium battery; pretreating the negative pole piece; and recycling the pole piece material. By preparing the efficient leaching agent, lithium iron phosphate can be leached, graphite black powder is regenerated while metal ions are leached, Fe < 2 + > is oxidized into Fe < 3 + >, ferric hydroxide is precipitated when a sodium carbonate solution is added subsequently, and nickel cobalt manganese and lithium cobalt oxide positive electrode materials are leached through lactic acid in the efficient leaching agent; the technology is simple, multiple waste lithium battery components can be recycled at the same time, the recycling efficiency is high, the leaching effect of all the metal components is good, and the leaching rate is high.

The invention relates to the technical field of lithium ion batteries, and discloses a lithium ion battery negative electrode material and a preparation method thereof, and a lithium ion battery, and the preparation method of the lithium ion battery negative electrode material comprises the following steps: mixing nanoscale silicon powder, carbon powder, a chiral ligand and a first dispersant, and grinding to obtain a silicon / carbon composite precursor; performing heat treatment on the silicon / carbon composite precursor in inert gas, and after cooling, performing grinding treatment to obtain a silicon / carbon composite material; and adding a second dispersant and a surfactant into the titanium-containing compound to obtain a titanium dioxide precursor solution, dispersing the silicon / carbon composite material into the titanium dioxide precursor solution to obtain a silicon / carbon / titanium dioxide composite precursor, and calcining the silicon / carbon / titanium dioxide composite precursor to obtain the lithium ion battery negative electrode material. The problem of serious volume expansion of the silicon material in the charging process of the lithium ion battery can be effectively solved, and the cycling stability of the lithium ion battery is improved.

The invention discloses a pre-lithiation silicon-based carbon composite material and a preparation method and application thereof, comprising the following steps: mixing tetramethoxysilane with an aminated polymer solution, collecting precipitation by centrifugation, vacuum drying and crushing to obtain a polymer chain / silicon dioxide composite powder; compounding Li-MOF powder and the polymer chain / silicon dioxide composite powder in anhydrous ethanol, vacuum drying and carbonizing under nitrogen protection to obtain the pre-lithiation silicon-based carbon composite material; in the invention, the surface of nano-silicon dioxide is wrapped by polymer chains and Li-MOF, the silicon-based carbon composite material formed after carbonization has high bonding strength between the silicon-based material and the carbon material, and the silicon-based material is evenly dispersed in the carbon material, the Li element in the Li-MOF is sublimated by the high temperature during carbonization, the gaseous Li element reacts more fully with the silicon dioxide by thermal reduction, and the pre-lithiation silicon-based carbon composite material with good bonding uniformity between the carbon material and the silicon material and high strength is obtained.