20results about How to "Buffer volume expansion" patented technology

The invention discloses a silicon-oxygen-carbon-based negative electrode material and a preparation method thereof, and belongs to the technical field of lithium battery negative electrode materials, and the preparation method comprises the following steps: (1) mixing alcohol, water and acid to prepare an acid solution with the pH value of 2-4, adding organosiloxane into the acid solution, and stirring in a water bath to obtain a siloxane hydrolysate; (2) adding a pyrene compound into the siloxane hydrolysate, and carrying out ultrasonic treatment; (3) adding alkali, stirring in a water bath at 20-50 DEG C for 1-3 hours, and then freeze-drying to obtain a precursor of SiOC; and (4) placing the precursor in an atmosphere furnace, sintering in an argon atmosphere, and naturally cooling to obtain the modified negative electrode material SiOC. The amorphous carbon content of the prepared SiOC is increased, on one hand, the electronic conductivity of the SiOC can be improved, and on the other hand, volume expansion in the charging and discharging process can be relieved.

The application relates to a silicon-carbon composite material and a preparation method thereof, a negative active material, a negative electrode sheet, a secondary battery and an electric device. The silicon-carbon composite material comprises porous carbon and a zinc silicate-silicon-oxygen-carbon composite material; at least part of the zinc silicate-silicon-oxygen-carbon composite material is filled in the pores of the porous carbon; the zinc silicate-silicon-oxygen-carbon composite material is of a porous structure; the pore diameter of the zinc silicate-silicon-oxygen-carbon composite material is 1-5 nm; and the mass content of zinc elements in the zinc silicate-silicon-oxygen-carbon composite material is 1-6%. The zinc silicate-silicon-oxygen-carbon composite material has proper pore diameter and zinc element content, is good in structural stability, and has low volume expansion rate and good conductivity. Since part of the zinc silicate-silicon-oxygen-carbon composite material is filled in the pores of the porous carbon, the volume expansion of the silicon-carbon composite material is further buffered. In the electrochemical cycle process, the silicon-carbon composite material has low volume expansion, and the cycle stability of the secondary battery can be improved.

This invention relates to the field of lithium-ion battery technology, specifically to a composite electrode material and its preparation method. The preparation method includes the following steps: using tin, red phosphorus, and lithium salt in a molar ratio of 3.5–3.9:3:0.5–0.1 as raw materials, ball milling is performed in an inert gas to obtain lithium-doped tin phosphide material; the lithium-doped tin phosphide material and carbon nanotube material are mixed uniformly, and calcined under a protective atmosphere to construct a carbon conductive network on the surface of the lithium-doped tin phosphide material to obtain modified tin phosphide material; the modified tin phosphide material is mixed uniformly with additives to obtain the composite electrode material. This invention achieves multi-dimensional modification of tin phosphide anode material through stepwise synergistic processing, solving the technical problem of decreased electrochemical performance of existing tin phosphide anode materials due to volume expansion and lithium loss.

The application provides a positive electrode material and a preparation method and application thereof. The positive electrode material is indicated by a gas generation index of the positive electrode material obtained based on a cumulative particle size distribution change rate of the positive electrode material after being pressed under different pressures. The positive electrode material has good structural stability and particle pressure strength, is not easy to break, can reduce the volume expansion of a battery, and improves the performance of the battery.

This invention discloses a method for preparing a graphene / silicon-carbon composite anode material. The method includes: firstly, preparing a carbon-coated silicon dioxide precursor via a hydrothermal reaction; then, converting it into a carbon-coated silicon material using a magnesothermic reduction method in the presence of sodium chloride, effectively inhibiting the aggregation and growth of silicon particles; finally, combining graphene with the carbon-coated silicon material through a secondary hydrothermal and calcination treatment to construct a conductive network. This invention, through a multi-level structural design, utilizes the synergistic buffering effect of the internal carbon layer and the external graphene to effectively alleviate the volume expansion of silicon during charging and discharging, significantly improving the conductivity and structural stability of the material. The prepared composite anode material exhibits high specific capacity and excellent cycle performance, making it suitable for lithium-ion battery applications.

This application relates to the technical field of lithium-ion battery materials, specifically disclosing a high-efficiency silicon-oxygen composite anode material, its preparation method, and its application. The preparation method of this anode material includes the following steps: mixing a siloxane with a fatty acid at a mass ratio of 1:(5~35), and ball milling under inert gas protection to obtain a pre-coated mixture; heating the pre-coated mixture to 50~1500℃ under an inert atmosphere and holding for 1~20h to obtain a carbon-coated silicon-oxygen material; immersing the carbon-coated silicon-oxygen material in a lithium-rich organic composite solution, holding at -5~25℃ under inert gas protection for 5~180 minutes, and drying to obtain a pre-lithiation product; mixing the pre-lithiation product with a nitride at a mass ratio of 1:(0.1~5), and ball milling under inert gas protection to obtain the high-efficiency silicon-oxygen composite anode material. This application can synergistically improve the stability and initial efficiency of the silicon-oxygen composite anode material.

This application provides a dynamic ion transport binder and its preparation method, a silicon-based anode, and an all-solid-state lithium-ion battery, relating to the field of solid-state batteries. The raw materials of the dynamic ion transport binder, by mass (100%), include: 60-80% nitrile compounds, 10-30% ether-based ion compounds, and 5-10% borate compounds. The dynamic ion transport binder employs a low-polarity elastic main structure, avoiding the introduction of a large number of highly active groups such as carboxyl and hydroxyl groups, thus effectively inhibiting the decomposition of sulfide electrolytes. The borate ester dynamic bonds formed by the borate compounds undergo reversible breakage and reconstruction under stress, thereby mitigating volume changes during silicon anode cycling. This dynamic ion transport binder can effectively improve the structural integrity of the silicon-based anode after cycling, reducing interfacial delamination and crack formation.

The application discloses a silicon-based negative electrode material, which comprises, from inside to outside, a core carbon layer, a gradient silicon-carbon composite layer, an intermediate silicon layer, a dispersed silicon layer and a boundary carbon layer; the core carbon layer is a dense carbon layer; the gradient silicon-carbon composite layer comprises a gradient porous carbon layer with gradually increasing porosity from inside to outside; silicon is deposited in the pores of the gradient porous carbon layer, and the content of the silicon gradually increases from inside to outside; the intermediate silicon layer and the dispersed silicon layer are sequentially coated on the outside of the gradient silicon-carbon composite layer; the boundary carbon layer is coated on the outside of the dispersed silicon layer; and part of the silicon particles in the dispersed silicon layer are embedded in the boundary carbon layer. The application further discloses a preparation method of the silicon-based negative electrode material and a lithium ion battery prepared from the silicon-based negative electrode material. The silicon-based negative electrode material can reduce the volume expansion of the electrode during the charging and discharging process, and improve the cycle life of the battery.

The application relates to the field of secondary batteries, in particular to a kind of antimony negative material and its preparation method, lithium ion battery and terminal, organic ligand containing carboxyl and mercapto, antimony source and polyethylene glycol are mixed to obtain solution A; Sodium borohydride and selenium source are added into ethanol, and then polyethyleneimine is added to obtain solution B; Solution A and solution B are mixed to carry out solvothermal reaction; The solvothermal reaction product is collected, washed and dried, and the lithium ion battery assembled by the antimony-based negative material of the application shows excellent electrochemical performance and can be used in various terminals.

This invention discloses a lithium metal anode based on a gradient solid-state electrolyte, its preparation method, and its application. The lithium metal anode sequentially comprises: a current collector, a porous lithium-zinc alloy interface layer, a lithium metal layer, and a gradient solid-state electrolyte layer. The gradient solid-state electrolyte layer includes a polymer matrix and a high-dielectric filler layer distributed in a gradient within the polymer matrix. In this invention, the porous lithium-zinc alloy interface layer and the gradient high-dielectric filler polymer layer work synergistically to effectively guide uniform lithium-ion deposition, suppress dendrite growth, and reduce tip effects, thereby improving cycle life, reducing interface impedance and polarization voltage, and minimizing volume expansion.

A negative electrode material, a preparation method thereof, a negative electrode sheet and a battery. The negative electrode material comprises a negative electrode active material and a coating layer existing on the surface of the negative electrode active material, wherein the coating layer comprises piezoelectric polymer fibers; the piezoelectric polymer fibers have a diameter of 500 nm to 2000 nm and a length of 100 mu m to 500 mu m. The negative electrode material provided by the application can effectively buffer the volume expansion of a silicon-based active material, reduce the interface transmission impedance, and help improve the capacity, rate performance and cycle life of the battery.

This invention discloses a bifunctional three-dimensional porous composite material and its preparation method and application. The method includes the following steps: (1) adding a carbon source to deionized water and stirring to obtain a uniformly dispersed solution; (2) dissolving a rare earth metal source, a transition metal source, and a sulfur source in deionized water and stirring to obtain a precursor solution; (3) mixing the solution obtained in step (1) and the precursor solution to obtain a mixed solution and performing a hydrothermal reaction; (4) repeatedly washing the product obtained in step (3), drying it, and then performing heat treatment to prepare the bifunctional three-dimensional porous composite material. The bifunctional three-dimensional porous composite material can effectively buffer the volume expansion effect of the sulfur cathode during charging and discharging and promote the full wetting of the electrolyte. On the other hand, it also improves the conductivity and catalytic activity of the composite material through the doping of rare earth elements, effectively improving the electrochemical performance of lithium-sulfur batteries.

This application provides an anode material for solid-state batteries, a method for preparing the same, and a solid-state battery, relating to the field of solid-state batteries. The anode material includes secondary particles, which are spherical in shape and formed by stacking multiple primary particles. The primary particles include graphite and a coating layer distributed on at least a portion of the graphite surface. The coating layer is made of at least one of titanium dioxide, alumina, lithium niobate, lithium zirconate, lithium fluoride, silicon, and tin. The anode material of this application, comprising graphite and a coating layer on the graphite surface, effectively physically isolates the graphite from the contact with the sulfide solid electrolyte, significantly suppressing side reactions at the interface and effectively improving the first-cycle coulombic efficiency and cycle stability of the anode material.

The invention discloses a potassium ion battery dual-binary alloy negative electrode and a preparation method and application thereof. The dual binary alloy negative electrode is obtained by dissolving commercial SbCl3, BiCl3 and CuSO4 in an acidic aqueous solution and then carrying out one-step substitution reaction through iron powder. The method is simple in process, low in cost and good in operability and repeatability, and the prepared material is high in parameter proportion adjustability. When used as the negative electrode of the potassium ion battery, the material has the advantages of improving volume expansion in an alloying process, accelerating transmission of potassium ions in a charging and discharging process and the like, and can be potentially applied to the negative electrode of the potassium ion battery in a large scale.

This invention belongs to the field of electrochemical technology and relates to a high-voltage resistant composite positive electrode sheet and its preparation method for suppressing gas generation during battery cycling. The composite positive electrode sheet includes a positive electrode sheet and a polymer coating on the active material layer of the positive electrode sheet. The polymer coating is a composite polymer coating formed by in-situ copolymerization of phosphorus-containing monomers and fluorinated acrylate monomers in the presence of polyethylene glycol borate under ultraviolet light. The mass ratio of the phosphorus-containing monomers, fluorinated acrylate monomers, and polyethylene glycol borate is (3~4):1:(0.15~0.4). The composite positive electrode sheet of this invention can suppress gas generation during battery cycling and improve its high-voltage resistance (≥4.3V vs Li). + / Li) stability.

This application provides a negative electrode active material and its preparation method, a negative electrode sheet, a sodium-ion battery, and electrical devices, relating to the field of sodium-ion batteries. The negative electrode active material includes a carbon matrix and phosphorus, nitrogen, sulfur, and boron doped into the carbon matrix; based on the total mass of the negative electrode active material, the phosphorus content is 1-10 wt%, the nitrogen content is 1-10 wt%, the sulfur content is 1-3 wt%, and the boron content is 1-3 wt%. The specific doping amounts of phosphorus, nitrogen, sulfur, and boron in this application, combined with the carbon matrix, enable the negative electrode active material to possess excellent cycle stability, excellent rate performance, and high capacity, while reducing volume expansion during cycling and minimizing adverse problems such as electrode breakage.

The application provides an alumina-carbon double-layer coated silicon composite material and a preparation method and application thereof, and relates to the technical field of lithium ion battery negative electrode materials.The application provides an alumina-carbon double-layer coated silicon composite material, which comprises nanosilicon, an amorphous carbon layer coated on the surface of the nanosilicon, and an alumina layer coated on the surface of the amorphous carbon layer.Through the double-layer coating of the carbon layer and the alumina layer, the problems of volume expansion of the silicon negative electrode, poor conductivity and instability of the SEI film are solved, the electrochemical reaction activity of the battery is increased, and the long cycle stability of the negative electrode material is significantly improved.The data of the embodiment show that the alumina-carbon double-layer coated silicon composite negative electrode material prepared by the application has a first circle discharge specific capacity of 2251.45 mAh / g at 0.1 C, and the reversible discharge specific capacity can reach 719.23 mAh / g after 1000 cycles at 0.5 C.

The invention provides a lithium ion battery and electric equipment. The lithium ion battery comprises a positive pole piece, a negative pole piece, an isolating membrane and electrolyte, the positive pole piece comprises a positive current collector and a positive film layer arranged on at least one surface of the positive current collector, and the positive film layer comprises a positive active material and a slow release agent; the positive electrode active material comprises lithium-containing olivine-type phosphate; the slow release agent comprises one or more of a lithium nickel cobalt manganese oxide, a lithium-rich manganese-based material, a lithium nickel cobalt oxide, lithium nickelate, lithium carbonate, lithium oxalate, Li5FeO4 and Li4SiO4; wherein based on the total weight of the positive electrode active material, the weight ratio of the slow release agent is less than or equal to 10%. According to the lithium ion battery, the slow release agent is arranged in the positive electrode film layer, so that lithium loss of the positive electrode active material is compensated in the cycle process of the lithium ion battery, and the cycle life of the lithium ion battery is prolonged.

This invention discloses a modified structure for an anode, a lithium metal anode containing the modified structure, and its applications, belonging to the field of new energy technology. The modified structure for the anode includes a tetramethylethylenediamine (TEDAM)-modified cellulose modification layer. The raw materials for the TDDAM-modified cellulose modification layer include cellulose, tetramethylethylenediamine, and a binder. In preparation, tetramethylethylenediamine is first reacted with cellulose to obtain TDDAM-modified cellulose, which is then mixed with the binder to form a slurry, which is then coated onto a substrate to form the modification layer. The modification layer of this invention utilizes the properties of tetramethylethylenediamine as a Lewis base catalyst to promote the reaction of amino groups with lithium metal to generate highly ionicly conductive Li3N, which helps to improve the ion transport rate of the lithium metal electrode. Simultaneously, the three-dimensional network structure constructed by nanoscale cellulose can uniformly disperse the lithium ion flux, suppress the growth of lithium dendrites and the instability of the solid electrolyte interface, and improve the safety of lithium metal batteries.

This invention discloses a pre-lithiated SiOx composite electrode material, its preparation method, and its applications, belonging to the field of material preparation technology. The preparation method includes: pre-treating a silicon oxide precursor with milling beads using a wet ball milling process under an inert atmosphere; forming a dispersion system by dispersing a metal salt and a fibrous template material in a lithium hydroxide solution; mixing the two systems and then inducing precipitation with an alcohol solvent to form a precursor; finally, acid treatment, washing, drying, and high-temperature carbonization under a protective atmosphere to obtain the final composite material. This material has a porous structure, with silicon oxide uniformly embedded in a highly graphitized carbon matrix. This invention features a simple process, stable interfacial bonding, effectively solves the volume expansion problem of silicon-based materials, and significantly improves electrochemical performance and cycle stability, making it particularly suitable as a negative electrode material for electrochemical energy storage devices such as lithium-ion batteries.