104results about How to "Small capacity attenuation" patented technology

The invention relates to a method for preparing a lithium ion battery anode material doped with a nanometer oxide, belonging to the technical field of manufacturing processes of lithium ion battery batteries. The method is characterized in that trace amount of nanometer oxide power is doped in the preparation process of lithium manganate, lithium cobaltoxide and lithium iron phosphate; the doping amount is 0.5-1.0 mol percent of lithium salts; and the nanometer oxide is selected from one or two of alumina, magnesia, titanium oxide, chromic oxide, nickel oxide, monox and zirconia and the nanometer oxide is subject to ball milling, drying, sieving, calcinating, crushing, grading and other processes to obtain the nanometer oxide doped or coated lithium ion battery anode material. The lithium ion battery anode material has reversible initial capacitance, and remarkably-improved attenuation property, charging-discharging properties, high-temperature circulating property and electrochemistry stability.

An object of the present invention resides in that under the use of an active material capable of attaining a high capacity, the volume expansion of the negative electrode is alleviated, the maintenance of the structure of the negative electrode is achieved, and the degradation of the battery capacity is suppressed. The present invention relates to a negative electrode for a coin-shaped lithium secondary battery, a coin-shaped lithium secondary battery including the negative electrode, and a method for producing the negative electrode for a coin-shaped lithium secondary battery, wherein: the negative electrode includes a molded negative electrode including a negative electrode active material capable of absorbing and desorbing lithium; the molded negative electrode is of a coin shape having two flat faces and a side edge, and has cracks along the thickness direction thereof; at least one of the two flat faces has recessed portions; and the cracks start from the recessed portions.

The invention relates to a preparation method of a carbon fiber/sulfur composite positive material with a multilevel structure and belongs to the technical field of chemical engineering electrode material preparation processes. The preparation method comprises the steps of preparing a carbon fiber by an electrostatic spinning method, adding metal salt into a spinning solution, calcining in an inert atmosphere, catalyzing graphitization of the carbon fiber by virtue of a metal formed in situ on one hand, removing metal particles to form hollow carbon spheres by virtue of the metal formed in situ on the other hand, and then adsorbing sulfur into the graphitized hollow carbon spheres by virtue of a gas-phase thermal evaporation method. With the adoption of the carbon fiber/sulfur composite positive material with the multilevel structure, the rate capability of the material is greatly improved, the dissolution of polysulfide is also inhibited, and the cycle performance and the coulombic efficiency of the material are improved. The preparation method is simple and easy, is high in controllability of technological parameters and low in energy consumption and has a low equipment requirement.

The invention belongs to the field of a lithium ion battery anode material and a preparation method thereof and application of a CNF-TMO lithium ion battery anode material. The method comprises the steps of: dissolving transition metal salt in an organic solvent, and adding polymer powder to fully dissolve and uniformly mix the transition metal salt and the polymer powder to obtain a spinning solution; performing spinning under the action of a high-voltage electrostatic field by setting spinning parameters to obtain a polymer-transition metal salt non-woven fabric; soaking the polymer-transition metal salt non-woven fabric in methanol solution of organic ligand to form one layer of organic metal frame material on the surface of the polymer fiber homogeneously under the action of the strongcoordination between the transition metal ion and the organic ligand to obtain a polymer-transition metal salt-organic metal frame material; then putting the polymer-transition metal salt-organic metal frame material into a tubular furnace, performing carbonizing of the polymer-transition metal salt-organic metal frame material at a high temperature under the flow of hydrogen/argon mixed gas to obtain carbon nano fiber-transition metal, thermally oxidizing the carbon nano fiber-transition metal in air, grinding and crushing the carbon nano fiber-transition metal to obtain a CNF-TMO lithium ion battery anode material.

The invention discloses a method for eliminating impurity influence of an all-vanadium redox flow battery electrolyte. The method comprises the steps of adding a complexing agent into the electrolyte, and fully stirring the electrolyte, wherein the complexing agent is phosphoric acid, inorganic phosphate, hydramine, amino carboxylate, hydroxy carboxylate or organic phosphate. By the method, the steps of impurity elimination during the preparation process of the electrolyte is omitted or reduced, the operation process is simple, the product is rich in raw material, complicated impurity elimination equipment is not needed to be matched, the impurity elimination cost is low, and the method is suitable for application on a large scale; by a mode of adding the complexing agent, impurity metal ions form a complexity body, a reaction electrical pair shifts out of a reaction potential section of an active substance of the all-vanadium redox flow battery electrolyte, the hydrogen evolution promotion effect of the metal ions is eliminated, the hydrogen evolution quantity of the redox flow battery is reduced, the capacity attenuation is reduced, and the lifetime of the redox flow battery is prolonged; and impurity ions introduced during the construction, running and maintenance process of the redox flow battery can be rapidly eliminated, and the method is simple and convenient and is suitable for promotion and application.

The invention discloses a multipoint temperature control protective method of a lithium-ion power battery. Multiple thermistors which are used for detecting the temperatures of measuring points are mounted on a lithium-ion power battery, and the thermistors are connected with a fixed resistor. The protective method comprises the following steps: acquiring values of the thermistors at the current measuring points; obtaining temperature values of various measuring points according to the values of the thermistors; comparing the temperature values of the various measuring points, and taking corresponding measures according to a compared result. The invention also relates to a device for realizing the protective method. The multipoint temperature control protective method and device of the lithium-ion power battery have the beneficial effects that the battery can be protected in time, the service life of the battery can be prolonged, the capacity fading of the battery can be slowed down, and the actual temperature of the battery can be reflected in time.

The invention belongs to the technical field of a sodium ion battery, and particularly relates to a negative electrode material phosphorus-sulfur double-doped hard carbon microsphere for a sodium ion battery and a preparation method of the negative electrode material. The negative electrode material for the sodium ion battery is a sucrose-based hard carbon material doped with elements sulfur and phosphorus and is an irregularly-shaped microsphere body, and the diameter of the microsphere is 3-10 micrometers. The material is prepared by hydrothermal reaction and high-temperature solid-phase reaction, metal sodium is used as a counter electrode, and in the sodium ion battery packaged from the material, the reversible capacitor of the sodium ion battery is about 340mAh/g under the current density being 30mA/g, and the specific capacity still can be maintained at (170-340)mAh/g after 3,500 circles and under a large current being 600mA/g. The electrode material has the advantages of high specific capacity, good rate performance, simple preparation method and low cost in raw material, and is applicable to a power type sodium ion battery.

The invention provides a positive active material with a phosphate coated spinel structure. The positive active material contains lithium-containing compound particles which have the spinel structure and the chemical formula LiMn(2-x)AxOy and a phosphate coating layer coating the surfaces of lithium-containing compound particles, in the chemical formula LiMn(2-x)AxOy, A is selected from one or more of Ni, Fe, Co, Ti, Y, Sc, Ru, Cu, Mo, Ge, W, Zr, Ca and Sr, x is larger than or equal to 0 and smaller than or equal to 0.7, and y is larger than or equal to 3.8 and smaller than or equal to 4.2; the lithium-containing compound particles have transition layers, and the transition layers contain dispersion elements which are diffused to enter the lithium-containing compound particles through coating and optional calcination. The invention also provides a preparation method of the positive active material and an application of the positive active material in a lithium ion secondary battery. The positive active material has improved circulation stability and coulombic efficiency when used in the lithium ion secondary battery.

The invention discloses a self support high density metal oxide/nitrogen doped graphene composite electrode, and a preparation method and application thereof. The composite electrode is prepared by the following steps of firstly obtaining nitrogen doped graphene through water bath reaction; then, dispersing the nitrogen doped graphene into an organic solvent; dripping the organic solvent dissolvedwith metal salt; performing uniform dispersion; then performing hydrothermal reaction; preparing a powdery metal oxide/nitrogen doped graphene composite material; then, adding a small amount of graphene oxide so that the powdery metal oxide/nitrogen doped graphene composite material is uniformly dispersed into graphene oxide; preparing metal oxide/nitrogen doped graphene water gel through secondary hydrothermal reaction; finally performing slicing and natural shrinkage drying. The composite material has a self support structure; the density is greater than 1.0g/cm<3>; through a two-step hydrothermal method, an obtained electrode plate can be directly used as an electrode of a lithium ion battery or a sodium ion battery; the electric chemical performance of high volume capacity, high reversibility and high power performance is realized.

The invention belongs to the field of lithium ion batteries, and discloses a CNF-metal compound independent electrode material and preparation method and application thereof. The preparation method comprises the steps of dissolving a metal salt in dimethylformamide, adding polyacrylonitrile powder again, and performing uniform mixing to obtain a mixed spinning liquid; spinning under a high-voltageelectrostatic field to obtain polyacrylonitrile-metal salt composite non-woven fabric; immersing the polyacrylonitrile-metal salt composite non-woven fabric in a methanol solution of an organic ligand, uniformly forming a layer of organic metal framework material on a polyacrylonitrile fiber surface by a strong coordination effect of dissolved-out metal ions and the organic ligand so as to obtaina polyacrylonitrile-metal salt@organic metal framework; and placing the polyacrylonitrile-metal salt@organic metal framework in a tubular furnace, allowing the polyacrylonitrile to be pre-oxidized under 280 DEG C, performing high-temperature carbonization under a mixed atmosphere of hydrogen and argon, and finally, performing oxidization, vulcanization or selenylation to obtain the sheet-shaped CNF-metal compound independent electrode material. The CNF-metal compound independent electrode material is cut into an electrode plate and is directly used as a negative electrode in a lithium ion battery.

The invention discloses an organic phase electrolyte and an application thereof in a negative electrode of a redox flow battery. The organic phase electrolyte consists of active materials, a supporting electrolyte and an organic solvent, wherein the active materials are diphenyl ketone and a derivative thereof, anthrone and a derivative thereof, or dibenzoyl methane and a derivative thereof; the supporting electrolyte is selected from tetraethylammonium hexafluorophosphate, tetraethylammonium tetrafluoroborate, tetrabutylammonium hexafluorophosphate or tetrabutylammonium tetrafluoroborate; and the organic solvent is selected from acetonitrile, tetrahydrofuran, propylene carbonate, ethylene carbonate, dimethyl sulfoxide, dimethylformamide, glycol dimethyl ether or ethylene glycol diethyl ether. The organic phase electrolyte disclosed by the invention has relatively low electrochemical potential and high electrochemical property; when the organic phase electrolyte is used as the negative electrode electrolyte of the redox flow battery for assembling an organic phase redox flow battery, relatively high open-circuit voltage can be realized, so that the energy density of the battery can be improved; and meanwhile, the capacity fading of the battery can be lowered, so that the cycle life of the battery can be prolonged.

Disclosed is a super capacitance battery. An anode comprises an anode current collector and an anode material coated on the anode current collector, the anode material comprises an anode active material, a first binder and a first conductive agent, the anode active material is composed of a carbon material and a lithium ion material, the content of the carbon material in the anode active material is larger than or equal to 70% and smaller than 100%, a cathode comprises a cathode current collector and a cathode material coated on the cathode current collector, the cathode material comprises a cathode active material, a second binder and a second conductive agent, the cathode active material is composed of a silicon mixture and graphene according to the mass ratio of 1-20:80-99, and the silicon mixture is composed of monatomic silicon and silicon dioxide according to the mass ratio of 1:19-19:1. The cathode of the super capacitance battery is provided with a low potential platform, so that average working voltage of the super capacitance battery is increased, and the super capacitance battery has high-ratio power characteristics and high-ratio energy characteristics. In addition, the invention further provides a preparation method for the super capacitance battery.

The invention discloses a method for repairing oxygen defect in a preparation process of spinel lithium manganate as a lithium-ion cathode material. The method comprises the following steps: (1) taking lithium carbonate and electrolytic manganese dioxide as main reaction substances and doping with aluminium hydroxide; (2) weighing reactants in proportion and putting the reactants in a horizontal-type ball mill tank for coarsely mixing; (3) putting the coarsely mixed materials into an automatic granulator for finely mixing and directly granulating the materials in the granulator after finely mixing; (4) putting the granulated materials in a drying oven for drying and putting the dried granulated materials into an atmosphere furnace for calcining for the first time; and (5) smashing the calcined materials, supplementing the lithium and carrying out secondary calcining. With the adoption of the method, the material performance is improved; and the preparation process is simple and easy in operation; the raw materials are easily available; and the obtained product is uniform.

The invention provides a double crosslinking binder for a silicon-based negative electrode material for a lithium battery, a silicon-based negative electrode material for the lithium battery, a preparation method, a negative electrode of the battery and the lithium battery. The double crosslinking binder comprises polyacrylic acid and diisocyanate. According to the double crosslinking binder, polycondensation reaction of the diisocyanate and carboxyl of the polyacrylic acid is achieved under a room-temperature condition through adding the diisocyanate, and the double crosslinking binder playsa further stabilizing role on a polymer binder, formed by the polyacrylic acid, with a network structure, thereby achieving double crosslinking; the double crosslinking binder is extremely low in consumed energy; and meanwhile, the adverse effect, caused by repeated volume change, of the silicon negative electrode in charging and discharging processes of the battery is avoided, the cycle performance of the silicon-based negative electrode material is improved, the capacity attenuation of the battery is small and the defects of the prior art are overcome.

The invention provides a positive electrode material with an improved nanoscale structure for a lithium-ion battery. The positive electrode material comprises two kinds of particles which are alternately arranged in structure, wherein the particles comprise layered positive active materials and spinel positive active materials; the layered positive active materials and the spinel positive active materials are alternately arranged to form the particles; the layered positive active materials comprise xLi<2>MO<3>.(1-x)LiMO<2>, wherein x is smaller than 1 and greater than or equal to 0; the spinel positive active material comprise LiM<2>O<4>; and M is one or more of metallic elements of which the atomic numbers are greater than 6. The invention further provides a preparation method of the positive electrode material with the improved nanoscale structure for the lithium-ion battery.

The invention relates to a composite positive electrode material based on 3D graphene and a preparation method thereof. The composite positive electrode material contains three-dimensional graphene and nano metal nickel, wherein the nano nickel particles uniformly disperse in the channels of three-dimensional graphene, the three-dimensional comprises a plurality of graphene molecules interconnected through a plurality of small organic molecules, and the nano nickel particles are introduced into the channels of the three-dimensional graphene by an in-situ reduction reaction. The composite positive electrode material provided by the invention has good electronic conductivity, is conducive to the effective electron transfer between the electrode and the collector, realizes high utilization of active materials, and is beneficial to improve the specific capacity and cycle stability of the battery. In addition, the preparation process is simple, environmental-friendly and low-cost, and the material has controllable morphology.

The invention provides an aqueous electrolyte, an aqueous metal ion battery and a preparation method thereof. The invention relates to the technical field of ion batteries, and provides an aqueous electrolyte with water as a solvent, water-soluble metal salt as a solute and one or more of C1-C10 alcohols, C1-C10 acids, pyridine and methanesulfonic acid as additives, and the mass fraction of the additives is 0.001%-10%. The aqueous electrolyte disclosed by the invention has flame-retardant and explosion-proof functions; safety accidents such as deflagration caused by thermal runaway of the battery in the overcharge and overdischarge process can be effectively inhibited; dendrite generated by the negative electrode in a metal electrodeposition reaction can be effectively inhibited, the uniformity of the electrodeposition reaction of the negative electrode is improved, capacity attenuation and battery failure caused by micro short circuit of the positive electrode and the negative electrode are reduced, and the cycling stability and the service life of the battery are remarkably improved.

The invention relates to the technical field of lithium ion batteries, and especially relates to a secondary lithium ion battery, and a method used for improving the electric capacity of the secondary lithium ion battery. The method provided by the invention comprises steps that: an air sac is produced form a polypropylene film, and sufficient electrolyte is filled in the air sac; an inverted U-shaped port of the air sac is extended into a liquid filling hole, and the inverted U-shaped port and the liquid filling hole form a sealed connection; when the secondary lithium ion battery is formed, a liquid filling space in the battery generates gas which is discharged upwards into the air sac; the electrolyte in the air sac flows into the liquid filling space in the battery for supplementing electrolyte consumed by battery formation. With the method provided by the invention, under a condition that a battery housing and a battery core are not changed, the electric capacity is optimized, the capacity attenuation is slow, the circulation performance is good, and the service life is long. With the method, efficiency can be improved, cost can be reduced, and product qualification rate can be ensured.