211results about How to "High theoretical capacity" patented technology

A negative electrode material for a nonaqueous electrolyte secondary battery having a high discharge capacity and a good cycle life is made from alloy particles having an average particle diameter of 0.1-50 mum and including Si phase grains 40 and a phase of a solid solution or an intermetallic compound of Si and other element selected from Group 2A elements, transition elements, Group 3B elements, and Group 4B elements from the long form periodic table (for example, an NiSi2 phase 42 and an [NiSi2+NiSi] phase 41) at least partially enveloping the Si phase grains. 5-99 wt % of this material is Si phase grains. The alloy particles can be manufactured by rapid solidification (such as atomization or roller quenching) of a melt including Si and the other element, or by adhering the other element to Si powder by electroless plating or mechanical alloying and then performing heat treatment. Even if rapid solidification is carried out, a negative electrode material having a good discharge capacity and cycle life is obtained without heat treatment.

Nanowire array compositions in which nanowires containing at least one Group IV metal (e.g., Si or Ge) in a single layer or core-shell nanowire structure, wherein, in particular embodiments, the nanowires have a transition metal core and/or are surrounded by or embedded within a metal oxide or metal oxide-ionic liquid ordered host material. The nanowire compositions are incorporated into the anodes of lithium ion batteries. Methods of preparing the nanowire compositions, particularly by low temperature methods, are also described.

The invention relates to a high-density electrode, comprising an electrode active substance and carbon fiber having a filament diameter of 1 to 1,000 nm, wherein the porosity of the electrode is 25% or less. According to the invention, electrolytic solution permeability and electrolytic solution retainability, which are matters of importance in realizing a high-density electrode for achieving a battery having a high energy density, can be improved.

The invention relates to a high-density electrode, obtained by impregnating a high-density electrode which comprises an electrode active substance and carbon fiber having a fiber filament diameter of 1 to 1,000 nm and has a porosity of 25% or less, with a solid polymer electrolyte; and to a battery including the resultant (high-density) electrode. According to the invention, electrolytic solution permeability and electrolytic solution retainability, which are matters of importance in realizing a high-density electrode for achieving a battery having a high energy density, can be improved.

The invention belongs to the technical field of transition metal sulfide-carbon materials, and particularly relates to a vulcanized cobalt-nickel/graphene/carbon nano fiber composite material and a preparation method thereof. The preparation method includes the steps that polyacrylonitrile nano fibers are prepared through electrostatic spinning, oxidized graphene/polyacrylonitrile nano fiber aerogel is prepared through mechanical stirring and freezing drying, then graphene/carbon nano fiber aerogel is prepared through high-temperature carbonization, and finally, vulcanized cobalt-nickel nanosheets grow in situ on the graphene/carbon nano fiber aerogel through the one-step hydrothermal method. The vulcanized cobalt-nickel/graphene/carbon nano fiber composite material prepared through the method has the advantages that the material has a three-dimensional porous space structure, conductivity is good and chemical properties are stable, and can serve as an ideal high-performance electro-catalysis material and electrode materials of new energy devices such as lithium ion batteries and solar batteries.

The invention provides a transition metal chalcogenide nanosheet material and a preparation method thereof, a battery anode material, a secondary battery and an application thereof, and belongs to thetechnical field of transition metal chalcogenides. The invention provides a preparation method of a transition metal chalcogenide nanosheet material, comprising the following steps: dissolving raw materials in an aqueous solution of soluble salt, removing moisture to obtain a solid, sintering the solid, and washing to obtain a transition metal chalcogenide nanosheet material, wherein the raw materials include a chalcogen precursor and a transition metal precursor. According to the preparation method, the soluble salt is used as a template, is inexpensive, is environmentally friendly and is easy to remove in post-treatment, and the obtained transition metal chalcogenide nanosheet material has a thinner sheet thickness. Compared with a traditional silica template method or a hydrothermal method, the preparation method of the invention greatly shortens the synthesis cycle, is simple and feasible, is controllable, has characteristics of high yield and simple experimental operation, and issuitable for large-scale production.

The invention provides a Si-TiO2-C nano fiber composite thin film, a preparation method and an application thereof. The preparation method for preparing the Si-TiO2-C nano fiber composite thin film includes following steps: (1) providing a spinning liquid which contains nano silicon powder, a titanium precursor and a carbon precursor; (2) performing electrostatic spinning to the spinning liquid to prepare a nano fiber film; (3) pre-oxidizing the nano fiber film under an oxygen-containing atmosphere at 100-300 DEG C to obtain a stabilized nano fiber film; and (4) carbonizing the stabilized nano fiber film under an non-oxidizing atmosphere at 500-1000 DEG C to obtain the Si-TiO2-C nano fiber composite thin film. By means of the method, the Si-TiO2-C nano fiber composite thin film can be prepared quickly and effectively. The preparation method is simple in operations, is convenient and quick, and can easily achieve large-scale production.

An electrochemical cell includes a negative electrode that contains lithium and an electrolyte system. In one variation, the electrolyte system includes a first liquid electrolyte, a solid-dendrite-blocking layer, and an interface layer. The solid dendrite-blocking layer is ionically conducting and electrically insulating. The dendrite-blocking layer includes a first component and a distinct second component. The dendrite-blocking layer has a shear modulus of greater than or equal to about 7.5 GPa at 23° C. The interface layer is configured to interface with a negative electrode including lithium metal on a first side and the dendrite blocking layer on a second opposite side. The interface layer includes a second liquid electrolyte, a gel polymer electrolyte, or a solid-state electrolyte. The dendrite-blocking layer is disposed between the first liquid electrolyte and the interface layer.

The invention provides a silicon-carbon composite material of a closed cage structure and a preparation method of the silicon-carbon composite material of the closed cage structure. The silicon-carboncomposite material of the closed cage structure is a hollow filled structure material in a closed cage form; the core of the hollow filled structure material is a silicon material-filled porous carbon material; the porous carbon material is filled with a silicon material; the silicon material has the void content of 50-95% in the porous carbon material; and a carbon material coats the outside ofthe silicon material-filled porous carbon material and the specific component of the carbon material is (SiOx)yC, wherein x is smaller than or equal to 2 and greater than or equal to 0 and y is smaller than or equal to 1 and greater than 0. When the silicon-carbon composite material of the closed cage structure is used as a negative electrode of a battery, contact of the silicon material and an electrolyte is isolated, the life of the battery is prolonged and the capacity performance and the cycle performance of the battery are improved.

The invention belongs to the technical field of zinc ion batteries and relates to an aqueous zinc ion battery based on manganese dioxide/graphene and a preparation method. According to the zinc ion battery, carbon nanotube fiber uniformly loaded with a manganese dioxide/reduced graphene oxide composite material is used as a positive electrode, a fibrous zinc wire is used as a negative electrode; and the surfaces of the two electrodes are uniformly coated with a gel electrolyte, and then the two electrodes are mutually wound to form a winding structure. The preparation method comprises the following steps of: the preparation of a graphene oxide dispersion liquid; the preparation of a fibrous manganese dioxide/reduced graphene oxide positive electrode; and the assembly of a fibrous aqueous rechargeable zinc ion battery. The manganese dioxide/reduced graphene oxide composite material has a three-dimensional reticular frame structure with high conductivity, and therefore, the contact areaof a current collector and an active substance can be increased, contact resistance can be reduced, the performance of the fibrous battery can be improved, and the service life of the fibrous batterycan be prolonged. With the fiber battery woven into a fabric, wearable electronic equipment with excellent performance can be prepared.

The invention disclose a cobaltous oxide/carbon composite hollow nanostructure material of dodecahedron structure and application of the cobaltous oxide/carbon composite hollow nanostructure material in negative electrodes of lithium batteries, and belongs to the technical field of preparation of negative electrode materials for lithium batteries. The method comprises the following specific steps: (1) preparing and purifying an organic frame compound ZIF-67 containing cobalt metal; (2) reacting a dopamine monomer with the organic frame compound ZIF-67 containing cobalt metal to generate a cobalt ion coordinated hollow polymer nanostructure; and (3) under the condition of nitrogen production, carbonizing the hollow polymer nanostructure at the temperature of 500 to 600 DEG C to obtain the hollow nanostructure material. The dimensions of the hollow nanostructure material can be adjusted according to the dimensions of the template metal organic frame compound ZIF-67 nanostructure; in the performance testing process of lithium ion batteries, the hollow nanostructure material, as a negative electrode active material, has preferable cycle performance, rate capacity and stability. Therefore, the cobaltous oxide/carbon composite hollow nanostructure material, as the negative electrode active material, can be of preferable application values and prospects in the field of lithium ion batteries.

The invention relates to a silver loaded mesoporous silicon oxide coated ternary cathode material, and a preparation method and applications thereof. The preparation method comprises the following steps: dissolving lithium salts, nickel salts, cobalt salts, and manganese salts into a uniform medium, wetting the mixture by two chelating agents, adding ammonia liquor, adding a solution of two chelating agents into the inorganic salt uniform medium, heating the mixture under stirring to prepare dry gel; grinding the dry gel into powder, calcining the powder to obtain a ternary material; adding a water solution of the ternary material into tetraethyl orthosilicate, ethanol, and surfactant (cetyl trimethyl ammonium bromide), carrying out centrifugal precipitation, drying the precipitates, calcining the precipitates to obtain a silica-ternary shell-core cathode material; dissolving silver oxide into water to obtain a solution A; dissolving PVP into water to prepare a solution B; dropwise adding the solution B into the solution A to obtain a solution C; adding the silica-ternary shell-core cathode material into the solution C to obtain a solution D; dropwise adding a reducing agent into the solution D, and finally carrying out washing, suction filtration, and drying to obtain the final product. The preparation method is simple, the technological conditions are easy to realize, the energy consumption is low, and the preparation is pollution-free.

The invention provides a negative electrode active material for a lithium-ion/sodium-ion secondary battery, a negative electrode and a battery, belonging to the technical field of electrochemistry and batteries. The negative electrode active material comprises a phosphorus-germanium compound, or/and a first complex formed by the phosphorus-germanium compound and elementary P or/and elementary Ge, or/and a second complex formed by the phosphorus-germanium compound and conductive components, or/and a third complex formed by the first complex and conductive components. The negative electrode provided by the invention comprises the negative electrode active material. The negative electrode has the advantages of high specific capacity, high initial Coulomb efficiency, small charge-discharge voltage platform difference and good high-current charge-discharge performance.

The invention provides a lithium-ion battery anode material. A general formula of a compound of the lithium-ion battery anode material is M<x>Ti<2+xy-5x>Nb<10+x(4-y)>O<29>, wherein M denotes metal ions, x denotes the atomic weight of M in the compound, y denotes the valence state of the metal ions, and the relations that 0<x<=10, 0<y<=5, 2+xy-5x>=0, and 10+x(4-y)>=0 are met. The invention furtherprovides a non-aqueous electrolyte lithium-ion battery and a preparation method thereof. The lithium-ion battery anode material has high theoretical specific capacity, and high safety performance, andhas the advantages of high reversible specific capacity, high coulomb efficiency, excellent cycle performance and the like.

A method of making a negative electrode for an electrochemical cell includes applying a fluoropolymer via a deposition process to one or more surface regions of an electroactive material. The electroactive material may be selected from the group consisting of: lithium metal, silicon metal, silicon-containing alloys, and combinations thereof. The fluoropolymer reacts with lithium to form a composite surface layer on the one or more surface regions that comprises an organic matrix material having lithium fluoride particles distributed therein. Electrochemical cells including such negative electrode are also provided.

The invention relates to a nitrogen-doped carbon-coated hollow porous silicon dioxide/cobalt nano composite material and a lithium ion battery negative electrode material thereof. The preparation method of the nitrogen-doped carbon-coated hollow porous silicon dioxide/cobalt nano composite material comprises the following steps: by taking tetraethyl silicate as a silicon source, cobalt acetylacetonate as a cobalt source, dopamine hydrochloride as a carbon source and N,N-dimethylformamide as a solvent, reacting under a hydrothermal condition, and sequentially preparing hollow-hollow porous silicon dioxide spheres, a hollow-hollow porous silicon dioxide/cobalt composite material and a nitrogen-doped carbon-coated hollow-hollow porous silicon dioxide/cobalt nano composite material. The composite material prepared by the invention is prepared by a step-by-step growth step, has excellent cycling stability and rate capability as a lithium ion battery negative electrode, and is low in manufacturing cost, simple in process, low in equipment requirement and environment-friendly.

A highly-concentrated electrolyte system for an electrochemical cell is provided, along with methods of making the highly-concentrated electrolyte system. The electrolyte system includes a bound moiety having an ionization potential greater than an electron affinity and comprising one or more salts selected from the group consisting of: lithium bis(fluorosulfonyl)imide (LiFSI), sodium bis(fluorosulfonyl)imide (NaFSI), potassium bis(fluorosulfonyl)imide (KFSI), and combinations thereof bound to a solvent comprising dimethoxyethane (DME). The one or more salts have a concentration in the electrolyte system of greater than about 4M, and a molar ratio of the one or more salts to the dimethoxyethane (DME) is greater than or equal to about 1 to less than or equal to about 1.5. The one or more salts binds to the dimethoxyethane (DME) causing the electrolyte system to be substantially free of unbound dimethoxyethane (DME) and unbound bis(fluorosulfonyl)imide (FSI⁻).