148results about "Cell electrodes" patented technology

A prosthetic stented heart valve which includes a compressible and expandable stent structure having first and second opposite ends, an expanded outer periphery, and a compressed outer periphery that is at least slightly smaller than the expanded outer periphery when subjected to an external radial force. The valve further includes a valve segment comprising a dual-layer sheet formed into a generally tubular shape having at least one longitudinally extending seam, and a plurality of leaflets formed by attachment of an outer layer of the dual-layer sheet to an inner layer of the dual-layer sheet in a leaflet defining pattern. The valve segment is at least partially positioned within the stent structure. The valve may further include at least one opening in the outer layer of the dual-layer sheet that is spaced from both the first and second ends of the stent structure.

The invention discloses a silicon oxide/carbon cathode material of a lithium ion battery and a preparation method of the material. The silicon oxide/carbon cathode material is a three-layer compound material with a core-shell structure and takes a graphite material as an inner core, porous silicon oxide as a middle layer and organic pyrolytic carbon as an outermost covering layer; and the preparation method comprises a process of preparing porous SiOx and a carbon covering process. Compared with the prior art, active metal is added to reduce SiOx partially, the volume expansion effect of silicon particles is greatly reduced as the volume expansion effect of the silicon particles in the charging and discharging processes can be automatically absorbed by the obtained product structure, and the initial charging and discharging efficiency and the cycling stability are remarkably improved. The initial reversible specific capacity is larger than 600 mAh/g, the initial charging and discharging efficiency is higher than 88%, the capacity retention ratio is higher than 98% after the capacity is cycled for 50 times, the synthetic process is simple and easy to operate, the manufacturing cost is low, and the large-scale production is easy to realize.

The invention belongs to the technical field of transition metal sulfides, namely carbon materials, and particularly discloses a nickel cobalt sulfide/graphene/carbon nanotube composite material and a preparation method and an application thereof. The method comprises the following preparation processes: mixing graphene oxide with a carbon nanotube, and preparing a graphene oxide/carbon nanotube hybrid material through ultrasound; and carrying out in-situ growth of a nickel cobalt sulfide nanosheet on the graphene oxide/carbon nanotube hybrid material through a one-step hydrothermal process. The graphene oxide/carbon nanotube hybrid material prepared by the method has the advantages of a three-dimension porous space structure, excellent conductivity, large specific surface area, stable chemical property and the like; the final nickel cobalt sulfide/graphene/carbon nanotube composite material is controllable in morphology; the nickel cobalt sulfide nanosheet evenly grows on the graphene oxide/carbon nanotube hybrid material; and a unique base structure and high specific surface area of the graphene oxide/carbon nanotube hybrid material are fully utilized. The material disclosed by the invention can be used as an ideal high-performance electric catalytic material, and an electrode material for new energy devices of a lithium-ion battery, a super capacitor and the like.

The invention provides a nonaqueous-electrolyte battery which has a positive electrode 3 including a positive active material, a negative electrode 4 including a negative active material having a lithium insertion/release potential higher than 1.0 V (vs. Li/Li⁺), and a nonaqueous electrolyte, wherein an organic compound having one or more isocyanato groups has been added to the nonaqueous electrolyte.

The invention discloses a lithium-supplementing additive as well as a preparation method and application thereof. The lithium-supplementing additive is of a core-shell structure, a core material is aconductive carbon material, a shell material is lithium oxide, lithium oxide is deposited on the surface of the conductive carbon material, and nano-scale lithium oxide particles form a nano-layer shell. According to the lithium-supplementing additive, lithium oxide is composited with the conductive carbon material and is utilized for supplementing lithium, and the conductive carbon material is utilized for conducting electrons, so that the utilization rate of lithium oxide is increased, and lithium can be well supplemented to an positive electrode or a negative electrode. Furthermore, after lithium is removed from the lithium-supplementing additive, the conductive carbon material can be used as an electrode conducting material, and no impurity is introduced. The lithium-supplementing additive is safe, environmentally friendly and non-toxic, and a foundation is laid for the preparation of high-capacity lithium ion batteries.

Using thin-films of iron oxide as the active material of electrodes, supercapacitors are fabricated on various substrates in different shapes. By chemical oxidation the iron-oxide film is formed directly and conformably on the substrates in a short period of cooking. The iron oxide has a chemical composition of Fe.sub.x O.sub.y H.sub.z, where 1.0.ltoreq.x.ltoreq.3.0, 0.0.ltoreq.y.ltoreq.4.0, and 0.0.ltoreq.z.ltoreq.1.0. Substrates, as the current collector, tested includes Al, Ti, Fe, Cu and Ni. Measurements by cyclic voltammetry indicates that the iron-oxide electrodes in a selected electrolyte can store charges as high as 0.5 F/cm.sup.2 or 417 F/g of the electrode materials. Supercapacitors as prepared are economical and can be used as enclosure housings for portable electronics, power tools, and batteries. The supercapacitors can also be integrated with the frames and chassis of electric vehicles.

The invention relates to the technical field of lithium ion batteries, in particular to core-shell structured carbon for a cathode material of a lithium ion battery and a preparation method thereof, and the lithium ion battery taking the core-shell structured carbon as the cathode material and a preparation method thereof. The core-shell structured carbon comprises a hard carbon material serving as a 'core' and soft carbon 'shell' which is coated on the surface of the 'core'. On the one hand, the hard carbon material serving as the 'core' provides a large number of spaces for storing lithium and channels for lithium ions to move, and the energy density and power density of the material are improved, and on the other hand, the soft carbon 'shell' with a graphite structure ensures that the material has high coulombic efficiency and cycle performance, so that the lithium ion battery made of the core-shell structured carbon serving as the cathode material has high capacity, high power characteristic, high cycle performance and high first charge and discharge coulombic efficiency, the preparation method is simple, and the cost is low.

The invention relates to a surface coating modified lithium ion battery cathode material and a preparation method thereof. The surface coating modified lithium ion battery cathode material has a general chemical formula of LiNi<1-a-b>CoaAlbO2/M, wherein a is more than 0.1 and less than 0.3, b is more than 0.01 and less than 0.2, and M refers to a coating layer. The material is coated by adopting a dry method; the coating layer refers to one or a mixture of two of lithium iron phosphate and lithium ferric manganese phosphate; and the mass ratio of the coating layer to LiNi<1-a-b>CoaAlbO2 is (0.01-0.2):1. The surface coating modified lithium ion battery cathode material and the preparation method thereof disclosed by the invention have the advantages that the stability of the cathode material is improved, and the safety performance of the material is improved; and moreover, in the dry-method coating process, waste liquor is not produced, high-temperature sintering is not needed, and the energy consumption and cost can be reduced.

The invention provides a hydrothermal preparation method of a graphene-coated sulfur/porous carbon composite material and relates to a preparation method of the graphene-coated sulfur/porous carbon composite material for a positive electrode material of a lithium-sulfur storage battery. The hydrothermal preparation method is used for solving the technical problem that the electrochemical property of the positive electrode material of an existing lithium-sulfur battery, namely a graphene-coated sulfur-containing composite material, is low. The hydrothermal preparation method comprises the steps of mixing and scattering the sulfur/porous carbon composite material with graphene slurry or oxidized graphene slurry, carrying out hydrothermal synthesis to prepare a hydrogel column, and drying to obtain the graphene-coated sulfur/porous carbon composite material. According to the graphene-coated sulfur/porous carbon composite material prepared by utilizing the hydrothermal preparation method, the outer surfaces of the graphene sheet layers are coated with sulfur/porous carbon composite material particles, a graphene conduction network is generated among the particles, and the obtained graphene-coated sulfur/porous carbon composite material is in a hierarchical core-shell structure; the positive electrode material has the high specific capacity, the long cycle life and the good rate capability; the composite positive electrode material can be used as a positive electrode material in a lithium secondary battery.

The invention discloses a method for preparing a nickel-cobalt-manganese ternary material precursor. By virtue of the method, waste small-particle-size nickel-cobalt-manganese ternary material precursors in a product are separated out and recycled into a reaction kettle, so that the ternary material precursors with the particle size of 7-15 micro meters account for over 95% in the product.

The invention discloses an alumina coating method of a lithium ion battery positive electrode material. The method comprises the following steps: adding ammonia water to a positive electrode material suspended aluminum nitrate solution in a dropwise manner to form a precipitate coated by Al(OH)3, and heating the precipitate in an air atmosphere muffle furnace to form an alumina coated positive electrode material. The coating method can improve the charge and discharge capacity of the lithium ion battery and prolong the cycle life.

The invention relates to a lithium silicate-coated Ni-Co lithium aluminate positive electrode material and a preparation method thereof. The mass percent of lithium silicate in the material accounts for 1-10wt%, a coating layer with a thickness being 2-20 nanometers is formed from the silicon silicate and is coated on Ni-Co lithium aluminate, and the positive electrode material is a spherical particle with a grain size being 5-15 micrometers. The method comprises the following steps of (1) adding a silicon source into an organic solvent, performing uniform stirring, adding water, adding Co-Alnickel hydroxide, performing heating and stirring reaction, and performing drying to obtain silicon dioxide-coated Co-Al nickel hydroxide precursor powder; and (2) grinding and uniformly mixing the silicon dioxide-coated Co-Al nickel hydroxide precursor powder and a lithium salt, placing the mixture in a tubular furnace, and performing two-segment calcination under an oxidization atmosphere, thereby obtaining the lithium silicate-coated Ni-Co lithium aluminate positive electrode material. The positive electrode has relatively good cycle stability and large-rate discharging performance; and bythe method, the problem of lithium resided on a surface during conventional coating can be effectively reduced, and the method is low in cost and simple in process and is suitable for industrial production.

The invention relates to a method for coating an even and controllable deposit carbon layer on the surface of LiFePO4 particles serving as lithium ion battery cathode materials for increasing the LiFePO4 conductivity. The method adopts the concrete preparation processes that: LiFePO4 powders are placed in a constant temperature zone of a chemical vapor deposition furnace, then the air in the furnace is fully discharged for inputting inert gases, after the temperature rises to the set level, a carbon source gas is input for covering a conductivity carbon film on the surface of the LiFePO4 particles evenly, the LiFePO4 coated with the carbon film has excellent conductivity which is increased by five orders of magnitude compared with the condition before coating. The chemical vapor deposition temperature ranges from 580 to 720DEG C, the deposition time is from 1 to 10 hours, and the volume percent of the carbon source gas is between 1 and 20 percent, and a sample deposited with carbon is cooled to the room temperature with a natural furnace and is then taken out. The method can cover the conductivity carbon film on the surface of each LiFePO4 particle evenly for increasing the conductivity of LiFePO4, and the thickness of the conductivity carbon film can be accurately controlled in the range of 2 to 50 nanometers through adjusting parameters (deposition temperature, deposition time and carbon source gas volume percent) of the chemical vapor deposition process.

The present invention provides an electrochemical flow battery for electric energy storage, the said battery uses anode reactive materials (the material being oxidized during battery discharge) selected from complexed ionic form of late 3d transition metals, i.e., Mn, Fe, and Cu. The battery has significantly low cost due to use of these relative inexpensive metals.

The invention discloses a coating modification method for improving performance of a rich-lithium manganese-base positive electrode material. The rich-lithium manganese-base positive electrode material is arranged in the material, wherein the rich-lithium manganese-base material is Li[LixMn1-x-yMy]O2; praseodymium phosphate is arranged on a surface layer of the material; intermigration of a transition metal ion, a phosphate radical and a praseodymium ion exists in a coating process; and a new phase capable of conducting an ion and an electron is generated on an interface. The method comprises the following specific steps of ultrasonically dispersing the rich-lithium manganese-base material in secondary water or an organic solution to form a disperse and uniform suspension; dissolving praseodymate in the suspension; adding phosphoric acid or phosphate to allow a phosphate radical ion and the praseodymium ion to perform a precipitation reaction on the surface of the rich-lithium manganese-base material; generating an initial coating layer; obtaining slurry comprising the initial coating layer; and finally drying the obtained slurry and then calcinating the slurry to obtain the rich-lithium manganese-base anode composite powder material comprising a praseodymium phosphate coating layer. The rich-lithium manganese-base composite material comprising the praseodymium phosphate coating layer prepared by the method is low in cost, high in capacity, high in first efficiency, low in voltage drop, good in stability and good in rate performance.

The invention provides a cobalt sulfide material, a preparation method and application of the cobalt sulfide material. The cobalt sulfide material is prepared by the following steps: (1) mixing dimethyl aminodithioformic acid with cobalt chloride hexahydrate according to a mole ratio of 2 to 1 in water for reaction, thus obtaining a first product; (2) under the protection of inert gas, carrying out reaction on the dried first product at 500 to 900 DEG C for 2 to 3 hours, thus obtaining the cobalt sulfide material. The cobalt sulfide material provided by the invention can be applied to the field of hydrogen production from water through electro-catalysis.

The invention provides a preparation method of catalyst slurry for fuel cell coating, which includes: successively adding catalyst particles, deionized water, a proton exchange membrane solution, alcohol and a stabilizer into a container, and uniformly mixing and dispersing the component to prepare the catalyst slurry, which is 8-28% in solid content and 50-500 mPa*s in viscosity. The mass percentage of the catalyst particles is 6-21% and the mass percentage of the stabilizer is 0.5-5%. The invention also provides the catalyst slurry for fuel cell coating. The preparation method is simple andavailable, is simple in stirring and dispersion and can shorten the whole preparation time. The catalyst slurry is high in viscosity and solid content and is suitable for preparing a membrane electrode in a coating manner.

In an exemplified lithium ion capacitor, a negative electrode 20 has a first layer 21 and a second layer 22, the first layer 21 and second layer 22 are laminated to each other, and a lithium metal sheet 60 is placed between the first layer 21 and second layer 22, and accordingly one side of the lithium metal sheet 60 in the thickness direction contacts the first layer 21, while the other side in the thickness direction contacts the second layer 22. Since lithium in the lithium metal sheet 60 is easily doped by an active material near a contact part, the fact that both sides of the lithium metal sheet 60 in the thickness direction contact an active material allows for efficient pre-doping and consequent improvement of productivity.

An electrolyte for a rechargeable lithium battery is provided. The electrolyte includes a non-aqueous organic solvent and a lithium salt. The non aqueous organic solvent includes cyclic carbonate such as ethylene carbonate and propylene carbonate, chain carbonate such as dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate and methyl propyl carbonate, and alkyl acetate such as n-methyl acetate, n-ethyl acetate and n-propyl acetate. The electrolyte can be used in a rechargeable lithium battery to provide good low temperature characteristics and safety.

The invention belongs to the technical field of storage batteries, and particularly relates to positive lead paste of a storage battery and a preparation method thereof. The positive lead paste comprises following raw materials: 490-510 parts of high-oxidizability lead powder, 490-510 parts of low-oxidizability lead powder, 22-28 parts of red lead, 22-28 parts of yellow lead, 8-12 parts of tetrabasic lead sulfate, 1-3 parts of fumed silica, 1-3 parts of nano-silica, 0.3-0.7 part of terylene staple fiber having a length of 1-2 mm, 0.3-0.7 part of terylene staple fiber having a length of 3-5 mm, 45-55 parts of a sulfuric acid solution having a concentration of 1.4-1.6 g/cm<3> and 45-55 parts of a sulfuric acid solution having a concentration of 1.1-1.3 g/cm<3>. The lead paste is capable of facilitating preparation, filling and coating processes, enhancing the strength of polar plate, reducing the rejection rate of the polar plate, improving the battery capacity, increasing the deep discharging time, prolonging the service lifetime of the battery and improving the comprehensive performances of the battery. According to the lead paste and the preparation method thereof, the method and the design are reasonable, operation is simple, and the production efficiency is largely increased.

An aqueous precipitation process for the preparation of particles comprising primarily silver sulfate, comprising reacting an aqueous soluble silver salt and an aqueous soluble source of inorganic sulfate ion in an agitated precipitation reactor vessel and precipitating particles comprising primarily silver sulfate, wherein the reaction and precipitation are performed in the presence of an aqueous soluble carboxylic acid additive or salt thereof, the amount of additive being a minor molar percentage, relative to the molar amount of silver sulfate precipitated, and effective to result in precipitation of particles comprising primarily silver sulfate having a mean grain-size of less than 70 micrometers.

The invention discloses a treatment method of carbon felt for vanadium batteries, which comprises the following steps: oxidizing and activating carbon felt in 60-100 DEG C sulfuric acid for 0.5-4 hours or oxidizing and activating carbon felt in 20-30 DEG C sulfuric acid for 12-48 hours, and washing with water to obtain the activated carbon felt. Compared with other sulfuric acid or nitric acid oxidization methods, the invention firstly uses an alkaline solution to soak and wash the hydrophobic oil adhesive substances influencing the oxidizing process on the carbon felt surface, and then carries out the sulfuric acid oxidizing treatment, thereby increasing the oxo groups and other hydrophilic groups on the carbon felt molecules and enhancing the hydrophilicity and electrochemically active ion adsorption capacity of the carbon felt. The invention has the advantages of short treatment time and favorable carbon felt activation effect, and enhances the electrochemical activity of the carbon felt and the generation current value of the carbon felt as the vanadium battery electrode.

The invention discloses a composite phosphate type anode material for a lithium ion battery, and a preparation method thereof. The composite phosphate type anode material can cause the raw material containing metals, lithium and phosphorus source and/or superfine LiMPO4 and/or superfine Li5-yM'2(PO4)3 to react under inert or reducing atmosphere and high temperature to synthesize LiMPO4 and Li5-yM'2(PO4)3 composite phosphate with combined chemical bonds, and by adding a conductive agent ball grinder, the composite anode material with excellent electrochemical performance can be obtained. The composite anode material prepared by the method has the advantages of low cost, unique process method and good electrochemical performance; the industrialization is easy to achieve.

The invention discloses a modified lithium-rich manganese-based cathode material for a lithium ion battery. The structural general formula of the material is (La<1-x>Sr<x>)MnO<3-delta>, wherein x is equal to or greater than 0 and less than or equal to 0.3, a is equal to or greater than 0.8 and less than or equal to 1, and delta is equal to or greater than 0 and less than or equal to 0.75; the modified lithium-rich manganese-based cathode material is prepared through the method 1 or method 2 as follows: method 1: lanthanum salt, strontium salt and manganese salt are mixed according to the stoichiometric proportion to prepare a (La<1-x>Sr<x>)MnO<3-delta> precursor solution, then a complexing agent is added into the solution and stirred uniformly, the lithium-rich manganese-based cathode material is added into the solution, heating is performed to evaporate the solution to form gel, and finally the dried gel is calcined, so that the modified cathode material is obtained; method 2: a precursor solution is prepared according to the method 1, a complexing agent is added into the solution and stirred uniformly, then the mixed solution is heated until the solution is burnt into powder, the powder is pre-burnt and is mechanically mixed with the lithium-rich manganese-based cathode material, and the mixture is calcined, so that the modified cathode material is obtained.

The invention discloses a preparation method of octahedral porous molybdenum dioxide and an application of the octahedral porous molybdenum dioxide in a lithium-ion battery. The preparation method comprises the steps of: adding trimesic acid and tetramethyl ammonium hydroxide to a solution containing a copper salt and a phosphomolybdic acid and/or phosphomolybdate for stirring to form an emulsion; transferring the emulsion into a hydrothermal reaction kettle for hydrothermal reaction to obtain a precursor compound; and putting the precursor compound into a protective atmosphere, carrying out thermal treatment at a high temperature and then washing the product to obtain a porous octahedral molybdenum dioxide material which is formed by stacking and assembling ultrafine nanoparticles, is uniform in shape and form and good in stability and has a porous characteristic. The molybdenum dioxide material is applied to the lithium-ion battery as a negative electrode material, so that the rate capability and the cycling stability of the electrode material are improved under the premise of ensuring the specific capacity; the preparation technology of the molybdenum dioxide material is simple; the cost is low; and the molybdenum dioxide material has a relatively good research prospect.