117results about How to "Guaranteed cycle stability" patented technology

The invention relates to a nitrogen-doped carbon nanotube adopting a hierarchical structure and a preparation method. The material is doped with nitrogen and adopts the obvious hierarchical structure, and the carbon nanotube comprises tinier nitrogen-doped carbon particles. The preparation method comprises steps as follows: aniline is uniformly dispersed in an acid solution through stirring, an aniline suspension is obtained and subjected to ice bath treatment for 20-60 min, and stirring is kept in the ice bath process; an oxidizing agent is dissolved in deionized water through stirring and subjected to ice bath treatment for 5-30 min; stirring is stopped, an oxidizing agent solution is quickly poured into an aniline suspension mixed solution and subjected to ice bath treatment for 8-28 h, centrifugal washing is performed by the aid of deionized water and ethanol until a supernatant is clarified, and a sample is dried in an oven; the dried sample is ground, subjected to heat treatment in air and naturally cooled; a treated composite is calcined at the high temperature in an inert atmosphere and naturally cooled. The nitrogen-doped carbon nanotube has the advantages of high capacity, good rate capability and good circulating performance and can be used as an anode material for a lithium ion battery.

The invention discloses a safe high-voltage high-energy-density lithium ion battery and a preparation method thereof. The safe high-voltage high-energy-density lithium ion battery comprises a positiveplate, a negative plate, an electrolyte and a diaphragm; the positive plate comprises an aluminum foil current collector and a positive active material coating, the positive active material is a single crystal nickel cobalt lithium manganate mixture coated with titanium oxide according to a certain ratio, the negative plate comprises a copper foil current collector, a negative active material coating and a ceramic coating, the negative active material coating is coated with the ceramic coating, wherein the positive active material is one or two of single crystal NCM523 and single crystal NCM622 after being subjected to titanium oxide coating treatment, the negative active material is a high-capacity graphite material, the electrolyte is a high-voltage electrolyte, and the voltage range is4.0-6.0V. According to the lithium ion battery prepared by utilizing the material, the battery energy density is improved, and good safety performance is achieved while the battery has excellent cycling performance.

The invention discloses a lithium-supplemented electrode of a negative electrode of a lithium ion battery and a preparation method thereof, wherein the lithium-supplemented electrode with the negativeelectrode material or the electrode sheet being pre-lithium treated is coated with an organic thin film layer on the surface of the pre-lithium electrode, and the organic thin film layer is composedof an electrolyte lithium salt dissolved in an organic solvent. The organic coating liquid is prepared by coating electrolyte lithium salt on the surface of the pre-lithium electrode, forming an organic thin film layer on the surface of the pre-lithium electrode, preventing the pre-lithium layer of the pre-lithium electrode from being oxidized, improving the first efficiency, cycle stability and processing performance of the lithium ion battery, and reducing the influence of the production environment on the lithium supplement electrode.

The invention provides an electrolyte for a high-voltage lithium ion battery, and belongs to the field of a lithium ion battery. The electrolyte comprises a non-aqueous organic solvent, a lithium saltand an additive, wherein the non-aqueous organic solvent is an ester solvent, the mass percent of the non-aqueous organic solvent accounts for 95% or above, the lithium salt is LiPF6, the concentration of the lithium salt is (1.0-1.5)mol/L, the additive is a mixture of a dinitrile compound and a boron-containing compound, and the mass percent of the additive accounts for 1-5%. The electrolyte employing the mixture of the dinitrile compound and borate as an electrolyte additive is applicable to a high-voltage positive electrode material LiNi<0.5>Mn<1.5>O<4> system, it is found that the interface impedance of the lithium ion battery positive electrode material can be improved by such the electrolyte, and moreover, the cycle stability of the lithium ion battery under a normal temperature isimproved.

The invention provides a cross-linked modified polyimide single-ion polymer. The cross-linked modified polyimide single-ion polymer has a chemical structure shown as formula (I). Polyimide and a 4-styrene sulfonyl(benzenesulfonyl)imide lithium salt are combined together by utilizing an enol click chemical reaction through ultraviolet curing, anions are better fixed on a polymer, and the transmission distance of lithium ions is shortened, so that the lithium ion transference number and the ionic conductivity of the polymer electrolyte prepared from the material are improved; meanwhile, pentaerythritol tetra(3-mercaptopropionate) (PETMP) can be connected with a plurality of lithium salt molecules, so that more lithium sources are provided; the transference number of electrolyte Li<+> can beincreased due to low lithium ion delocalization energy of lithium disulfimide of the 1, 4-styrene sulfonyl(benzenesulfonyl)imide lithium salt; a plasticizer with good thermal stability is also added to improve the ionic conductivity; and then, the thermal stability and ionic conductivity of the polymer gel electrolyte and the cycling stability of the battery are ensured, and the use safety of thelithium ion battery is ensured.

The invention relates to a preparation method of multi-element cathode material coated by graphene. The active material of the multi-element cathode material comprises an inner layer and an outer layer, wherein the active material has the following chemical formula (1-a) LiNi1-xCoxO2.aLiMn0.3Al0.7O2, wherein a is equal to 0.3-0.35, and the x is equal to 0.25-0.45. The method comprises the following steps: (1) preparing the active material; (2) preparing graphene derivate materials; (3) coating the active material by the graphene derivate materials. The multi-element cathode material prepared by the method disclosed by the invention adopts a two-layer structures with various component matching ratios, the proportion of the nickel in the inner layer is the highest, so that the high capacity of the material is ensured; the outer layer has higher cobalt content, so that the cycling stability of the material is ensured; finally, another layer of graphene derivate material is adopted for coating the active material, so that the activity and the capacity of the material are further improved. Therefore, when the cathode materials are applied to lithium batteries, the specific capacity is higher, and the stability is good.

The invention provides a preparation method for a tin-carbon composite negative material. An outer layer of the tin-carbon composite negative material is a composite cladding layer jointly formed by asphalt, resin and tin powder, and an inner layer is the tin-carbon composite negative material which is composed of graphite and has a core-shell structure. In the tin-carbon composite material prepared according to the method, high specific capacity characteristic of tin is maintained, meanwhile, a modification effect on the graphite is played, the overall cyclic stability of the material is improved, the energy density of the negative material of a lithium ion battery is improved, thus, the negative material has higher specific capacity than the carbon negative material commonly used in the lithium ion battery in the current market, and the increasing energy density requirement of various portable electric devices on the battery is met.

The invention relates to a preparation method of a foamed nickel self-supporting nickel nanotube super capacitor electrode material, which comprises the following steps: pre-treating foamed nickel; growing zinc oxide nanorods on the surface of the pretreated foamed nickel by adopting a hydrothermal method or an electro-deposition method; electrically depositing an elemental nickel layer on the surface of the zinc oxide nanorods to obtain a zinc oxide@nickel core-shell structure; and finally, calcining and etching the zinc oxide@nickel core-shell structure. The preparation process is convenient, simple, green, environmentally friendly and low in cost. The problem that materials contain too many impurities and the operation is complex in a traditional process is solved. A super capacitor energy storage material containing novel nickel nanotubes is constructed from another direction. In addition, the nickel nanotubes are grown on the surface of the foamed nickel to serve as a self-supporting electrode material with good conductivity and a stable structure, the hollow tubular structure can provide a larger specific surface area, and the charge-discharge cycling stability of a whole capacitor is ensured while the conductivity is improved.

The invention relates to the technical field of battery negative electrode materials, and provides a silica negative electrode material and a lithium ion battery. The silica negative electrode material has a core-shell structure and comprises an inner core, a middle layer coating the surface of the inner core and an outer shell layer coating the surface of the middle layer; the material of the inner core comprises amorphous silicon oxide and silicon microcrystals, and the sizes of the silicon microcrystals are increased in a gradient manner along the direction from the center of the inner core to the surface layer of the inner core; the middle layer is made of silicon carbide; and the outer shell layer comprises a carbon layer. The negative electrode core material with the characteristics can guide huge volume expansion stress generated in a lithium embedding process to be released outwards through silicon microcrystals which are distributed in an amorphous silicon oxide main body material and have gradually changed sizes, so that volume expansion of the silicon-based negative electrode material is inhibited, and irreversible capacity increase caused by volume expansion is reduced; therefore, the cycle life of the silicon-based negative electrode material is effectively prolonged.

The invention discloses a preparation method for lithium battery anode slurry doped with tin powder. By adding nanometer tin powder in the conventional anode slurry preparation process, the capacity playing performance of the material is improved, and the requirements of a lithium ion battery for the high-energy density can be met; in addition, through the steps of thickening agent solution preparing, powder body dispersing, high-viscosity stirring, low-viscosity stirring, viscosity testing, vacuum defoaming and the like, all the components, especially the nanometer tin powder, are fully dispersed in an anode system, agglomeration of the nanometer tin powder is avoided, and the cycling stability is guaranteed. The preparation method has the advantages of being short in preparation time, little in equipment wear, low in production energy consumption, good in dispersion effect and the like. The lithium battery prepared by adopting the anode slurry is low in internal resistance, high in volume energy density and good in cycling performance.

The invention provides a device and a method for preparing ultra-high purity difluoromono-chloroethane. The device comprises a heat exchangeable photochlorination reactor, an HCL-removing tower, a chlorine-removing tower, a dry buffer tank, a single-stage oil-free compressor, a degassing tower, a rectifying tower, a molecular sieve drier and a product tank. The method comprises the following steps: mixing raw materials and feeding the mixture into a photochlorination reactor for reaction, feeding the reactant into a two-stage water absorption HCL tower and a two-stage alkali liquor absorption chlorine gas tower to remove HCL and chlorine; feeding the obtained product into a dry buffer tank; compressing the gas from the dry buffer tank with a single-stage oil-free compressor and feeding the compressed gas into a degassing tower and a rectifying tower for degassing and rectifying to obtain difluoromono-chloroethane with moisture; and then removing the moisture with a molecular sieve drier to obtain a pure difluoromono-chloroethane product. According to the device and the method, the production flow of the difluoromono-chloroethane is shortened, the reaction conversion rate is high, the by-products are few, the rectifying efficiency is high, the raw materials and the energy consumption are reduced, the purity of the product is high and the production of the whole set of device is safe and economic.

The invention relates to a carbon-azine composite water-based negative electrode material and application thereof. The carbon-azine composite water-based negative electrode material utilizes the conductivity, porosity and adsorbability of a nano carbon material and the reaction capability of polycyclic aromatic hydrocarbon-like compounds of the carbon material to carry out functionalized graftingto form a cross-linked network structure, so as to improve the liquid absorbency and ionic conductivity of the carbon material, and compound the heterocyclic azine compound onto carbon granules to form a carbon-azine composite material. The carbon-azine composite material is used as a water-based negative electrode, a sodium manganate or nickel hydroxide electrode is used as a positive electrode,and an electrolyte is a liquid or gel-state material taking sodium salt or sodium hydroxide as a solute and water as a solvent; and the positive electrode and the negative electrode are separated by adiaphragm to form a battery. The negative electrode material has high utilization rate and capacity, is applied to an aqueous rechargeable battery, and has high specific discharge capacity and good cycle performance; and a water-based rechargeable battery composed of the carbon-azine composite water-based negative electrode material and the sodium manganate or nickel hydroxide positive electrodehas the advantages of relatively high specific energy, safety, low cost, environmental protection and long cycle life.

The invention discloses a preparation method of an ultrathin carbon-coated tin dioxide nano composite material, which comprises the following steps: 1. dissolving a carbon source, a tin source and naphthalene in a certain ratio in deionized water, adding a proper amount of hydrochloric acid to regulate the pH value, and carrying out hydrothermal reaction on the mixed solution; and 2, calcining a product obtained by the hydrothermal reaction in a tubular furnace in an argon atmosphere to obtain the ultrathin carbon-coated tin dioxide nano composite material. The ultrathin carbon-coated stannicoxide nano composite material prepared by the invention has good cycling stability, excellent rate capability and high specific discharge capacity as a lithium ion negative electrode material.

The invention discloses a succinonitrile-based electrolyte coupled with an organic lithium salt and fluoroethylene carbonate, and relates to the technical field of lithium-ion batteries. The specificscheme is as follows: the succinonitrile-based electrolyte coupled with an organic lithium salt and fluoroethylene carbonate comprises succinonitrile, an organic lithium salt and fluoroethylene carbonate, wherein the molar ratio of the succinonitrile to the organic lithium salt is 100: 1-1:1, the organic lithium salt is a combination of a sulfonyl imide lithium salt and lithium oxalyldifluoroborate, the molar ratio of the sulfonyl imide lithium salt to the lithium oxalyldifluoroborate is 100: 1-1: 1, and the fluoroethylene carbonate accounts for 5-50% of the total volume of the succinonitrile-based electrolyte. The invention further discloses a preparation method of the succinonitrile-based electrolyte and application of the succinonitrile-based electrolyte to a lithium metal battery, theelectrolyte can form an organic-inorganic composite SEI film on the surface of metal lithium, side reaction of succinonitrile and metal lithium is avoided, and the interface stability and electrochemical performance of the battery are remarkably improved.

The invention discloses a method of preparing TiO2-modified P/C composite anode material and belongs to the field of electrochemical and new-energy materials. In the method, red phosphorus, anthraciteand nano-TiO2 are uniformly blended and then the mixture is mechanically ball-milled in a high-energy ball mill tank filled with inert gas, thus obtaining the TiO2-modified P/C composite anode material. Due to low cost of the anthracite, the method is suitable for low-cost large-scale production. The composite material is used as an anode of a sodium-ion battery and shows high reversible specificcapacity and great cycle stability. The method, as the anode of the sodium-ion battery, has certain application prospect.