32results about How to "Limit dissolution" patented technology

The invention relates to a carbon-sulphur composite used for a cathode material of a lithium sulphur battery as well as a preparation method and application thereof. The carbon-sulphur composite comprises a carbon material and elemental sulphur, wherein the carbon material is formed by doping mesoporous carbon with the aperture of 2-5nm and electroconductive carbon with the aperture of 30-70nm, and the electroconductive carbon with the aperture of 30-70nm contains micropores with the aperture of 0.5-1.7nm; and the elemental sulphur accounts for 10-90wt% of the total quantity of the composite. Abundant micropores guarantee that the carbon material has larger specific surface, adsorption capacity to polysulphide is stronger, and dissolution of the polysulphide can be effectively limited, so that stability of a sulphur electrode is improved. Meso pores in porous distribution can load more sulphur active substances, electrochemical capacity of a composite material is improved, and diffusion and transmission of lithium ions and electrolyte solution can be facilitated, so that reduction polarization of the elemental sulphur is reduced and discharge plateau of the elemental sulphur is improved.

Processes and apparatuses for micro-treating iron-based alloys to transform and / or shape them and the resulting materials obtained by treating low, medium, and high carbon steel and other iron-based alloys to form at least a mixed microstructure that may contain martensite, bainite and un-dissolved carbides, and may also contain complex steel microstructures including portions of bainite, coalesced bainite, acicular ferrite, retained austenite and / or martensite along with combinations thereof by micro-treating said iron based alloy.

The invention discloses a composite positive electrode for a secondary aluminum battery. The positive electrode is formed by compositing vertically-oriented graphene, polyacrylonitrile and sulfur, wherein the oriented graphene vertically grows on a conductive substrate material to form a three-dimensional conductive framework; the polyacrylonitrile uniformly coats the surface of the conductive framework; an active substance namely the sulfur is loaded finally. The specific surface area of the composite positive electrode is large, the conductive performance is excellent, the energy density is high, and the preparation process is simple, and suitable for industrial production; the secondary aluminum battery prepared from the composite positive electrode has higher specific capacity and excellent cycle performance.

The invention relates to a sodium-sulfur battery positive electrode material and a preparation method thereof. The sodium-sulfur battery positive electrode material is a sulfur-titanium dioxide-carboncomposite material, and the preparation method includes the following steps: firstly, preparing a metal organic framework material MIL-125, spray-drying and compounding the metal organic framework material MIL-125 with graphene, performing carbonization treatment to obtain a titanium dioxide-carbon composite material, and then doping sulfur to prepare a sulfur-titanium dioxide-carbon composite sodium-sulfur battery positive electrode material by using a ball milling method and a hot melting method. The composite material prepared by using the method has a larger specific surface area and porosity, can limit the 'shuttle effect' of polysulfide, reduces the dissolution of intermediate products, can improve the electrochemical activity of elemental sulfur, shortens the transmission paths ofelectrons and ions, limits the dissolution of polysulfide, and improves the electrochemical reaction speed of active materials adsorbed on the surface of a carrier.

The purpose of the present invention is to provide a medical material which has both safe cytotoxicity and efficient antibacterial and antiviral properties, a medical protective article, and a manufacturing method thereof. The multilayer copper-based zeolite fiber medical material has a four-layer structure which sequentially comprises an outermost layer, a first middle layer, a second middle layer and an innermost layer, wherein the outermost layer and the second middle layer are copper-based zeolite fiber layers, the first middle layer is a hydrophobic fiber layer, the innermost layer is a hydrophilic fiber layer, the porosity of the copper-based zeolite fiber layer on the outermost layer is greater than that of the hydrophobic fiber layer on the first middle layer; each copper-based zeolite fiber layer comprises copper-based zeolite and fiber yarn formed by winding fibers; the copper-based zeolite is independently dispersed on the surface of the fibers, and the mass of the copper-based zeolite is reduced in a gradient mode from outside to inside along the radial interface of the fiber line. The medical material and the prepared medical protective article have the two technical advantages of low cytotoxicity and high antibacterial and antiviral properties, have the effect of efficiently killing viruses (especially novel coronavirus) and enough biological safety, are expectedto rebuild the industrial standard of medical respirators, and have very high theoretical and industrial practical values.

The invention discloses a carbon-sulfur composite positive electrode material of a lithium-ion battery and a preparation method of the material. The positive electrode material comprises a shell layer and a nuclear layer, wherein the shell layer comprises a conducting polymer layer; the nuclear layer comprises a sulfur layer; and a nano conducting material is uniformly distributed in the sulfur layer and comprises more than one dotted nano conducting particles and more than one linear and / or piece-shaped conducting nano materials. The preparation process comprises the following steps of: (1) after uniformly mixing the nano conducting material and the sublimed sulfur, carrying out insulating treatment in closed environments with the temperatures of being 120-300 DEG C and 300-500 DEG C in sequence, and then naturally cooling to obtain the powder; and (2) carrying out ball-milling treatment on the powder obtained by the step (1), wrapping the powder by the conducting polymer, then cleaning, and drying under the condition with the temperature of being 80-120 DEG C, thus obtaining a target product. The invention has the advantages that the service life of the sulfur positive electrode material of the lithium battery can be effectively prolonged, the cycling performance of the sulfur positive electrode material can be improved, the single carrying amount of the sulfur can be improved, and the preparation process is simple and high-efficiency, and is low in cost and easy in large-scale production.

The invention belongs to the technical field of lithium-sulfur batteries and particularly relates to a high-sulfur-content carbon-sulfur material and a preparation method thereof; the carbon-sulfur material has three-dimensional porous structure and has sulfur content up to 85%; the preparation method of the carbon-sulfur material comprises the steps of I, mixing well a water-soluble sulfate, a water-soluble carbon source and water in a preset proportion to obtain mixed solution; II, adsorbing the mixed solution with foam material, and lyophilizing to obtain a precursor; III, thermally treating the precursor at high temperature to obtain an intermediate product; IV, adding the intermediate product into the solution with trivalent iron ions, allowing full reaction to obtain an initial reaction product; V, filtering the initial reaction product, washing, and drying to obtain the high-sulfur-content carbon-sulfur material. Compared with the prior art, the high-sulfur-content carbon-sulfur material has high sulfur content and good structural stability and may be used in lithium-sulfur battery cathodes to provide significant improvement in the cycle performance and rate performance of batteries.

The invention discloses a lithium-sulfur battery cathode material, and belongs to the technical field of lithium-ion batteries. The lithium-sulfur battery cathode material of the present invention is compounded by porous carbon and sulfur. The porous carbon is composed of an internal core and an external shell. The internal core is of a mesoporous carbon structure. The external shell is of a micro porous carbon structure. The sulfur is filled in the holes of the mesoporous carbon structure and the micro porous carbon structure. The invention also provides an electrode slice and a battery based on the cathode material. The mesoporous structure in the porous carbon has a large pore volume, and can support sulfur of a large weight. The micro porous structure of the outer layer of porous carbon carries sulfur of small molecules. Thus the porous carbon can effectively prevent dissolution of polysulfides in the charge-discharge process, and has excellent cycle stability when the cathode material is ensured to have a high specific capacity.

The invention relates to a carbon-sulfur composite for positive electrodes of lithium-sulfur batteries and its preparation and application. The composite includes carbon materials and elemental sulfur, wherein the carbon materials have a gradient ordered tertiary pore structure, and the pore diameter of the tertiary channels is The distribution range is that micropores less than 2nm are used as primary pores, small mesopores around 3-10nm are used as secondary pores, and large mesopores of 10-30nm are used as tertiary pores. The secondary pores are located on the pore wall of the tertiary pores. The primary pores are located on the pore wall of the secondary pores; the elemental sulfur is filled in the pores of the carbon material, and the elemental sulfur accounts for 10-80wt% of the total amount of the compound. The carbon-sulfur composite is used in lithium-sulfur secondary batteries, exhibits high sulfur utilization rate and good cycle stability, and has the advantages of simple preparation process, good repeatability, low cost and microscopic controllability.