The present invention provides a method for preparing a polyanion type sodium battery positive electrode material on the basis of an organic acid dissolution method, comprising the following steps: step S1: preparing a mixture of a transition metal source, a sodium source, and a polyanion source, and putting the mixture into a reactor, the transition metal source being a transition metal simple substance or a transition metal oxide; step S2, adding organic acid into the reactor, heating, and continuously stirring until the transition metal source is completely dissolved; step S3, adding a carbon source, stirring, and drying to obtain precursor powder; and step S4, heating the precursor powder in an inert gas atmosphere, and after the heating treatment is completed, cooling the precursor powder to room temperature along with a furnace to obtain the polyanion type sodium battery positive electrode material.

A ferrite particle having a spinel crystal structure belonging to a space group Fd-3m and having a ferrite composition represented by a specific formula, a carrier for an electrophotographic developer including the ferrite particle and a resin coating layer configured to coat a surface of the ferrite particle, an electrophotographic developer including the carrier for an electrophotographic developer and a toner, and a ferrite particle production method for producing the ferrite particle.

The present application provides a continuous reaction system, a ferromanganese phosphate precursor, a lithium iron manganese phosphate, a preparation method, and a secondary battery. A method for preparing a ferromanganese phosphate precursor provided in the present application is a continuous preparation method, thereby improving the production efficiency, and obtaining the ferromanganese phosphate precursor with small particle size, narrow particle size distribution, high crystallinity, monocrystal phase, regular appearance, high tap density, high batch stability, and high batch consistency.

Methods and systems for rapidly characterizing electrochemically active particle dispersions are provided. In various embodiments, the methods and systems advantageously reduce the system complexity to identify what fraction of a cell resistance may be due to the active material.

A process and reactor for arsenic fixation in which a first gas stream comprises oxygen and an iron-containing particulate material. The oxygen and particulate material may be fed to reactor through respective first and second inlets. A second gas stream containing one or more volatile arsenic compounds is fed through a third inlet and mixed with the first gas stream and the particulate material to produce a combined gas stream containing the volatile arsenic compounds and the particulate material. The arsenic compounds are reacted with iron in the particulate material as the combined gas stream flows through the reactor to produce solid iron arsenates which are then recovered. The portion of the reactor including the first, second and third inlets is vertically oriented, and the reactor may include a venturi arrangement having a throat at which the second inlet is located.

The invention relates to electrodes that contain active materials of the formula: A.sub.aM.sub.bX.sub.xO.sub.y wherein A is one or more alkali metals selected from lithium, sodium and potassium; M is selected from one or more transition metals and/or one or more non-transition metals and/or one or more metalloids; X comprises one or more atoms selected from niobium, antimony, tellurium, tantalum, bismuth and selenium; and further wherein 0<a6; b is in the range: 0<b4; x is in the range 0<x1 and y is in the range 2y10. Such electrodes are useful in, for example, sodium and/or lithium ion battery applications.

A method for preparing a suspension of LDH particles comprising the steps of: preparing LDH precipitates by coprecipitation to form a mixture of LDH precipitates and solution; separating the LDH precipitates from the solution; washing the LDH precipitates to remove residual ions; mixing the LDH precipitates with water; and subjecting the mixture of LDH particles and water to a hydrothermal treatment step by heating to a temperature of from greater than 80 C. to 150 C. for a period of about 1 hour to about 144 hours to form a well dispersed suspension of LDH particles in water, wherein said LDH particles in suspension comprise platelets having a maximum particle dimension of up to 400 nm.

Provided is a cleaning device for cleaning a magnet powder including: a flask provided to contain the magnet powder and a cleaning material used to clean the magnet powder; and a vacuum manifold provided to maintain the magnet powder and the cleaning material contained in the flask in an inert state during cleaning.

Provided is a method for cleaning a magnet powder including a loading operation for loading a magnet powder, a cleaning solution, and zeolite into a flask; a gas injecting operation for injecting an inert gas into the flask; and a vacuum drying operation for drying the magnet powder and the zeolite in a vacuum.

Provided is a method for manufacturing a magnet powder including: preparing a primary mixture by mixing neodymium (III) nitrate, boric acid, and iron (III) nitrate nonahydrate; preparing an oxide by heat-treating the primary mixture; removing a residual organic material of the oxide by heat-treating the oxide; preparing a hydrogen-reduced oxide by reacting the oxide, from which the residual organic material is removed, with hydrogen by heat treatment; preparing a secondary mixture by mixing the hydrogen-reduced oxide with calcium; obtaining a product by subjecting the secondary mixture to reduction-diffusion reaction by heat treatment; and obtaining Nd.sub.2Fe.sub.14B powder by pulverizing the product.

Exemplary layered double hydroxides (LDHs) may comprise a compound of formula Mg.sub.4-yAlX.sub.y(OH).sub.2, wherein X is Mn.sup.+2, Cu.sup.+2, Zn.sup.+2, or Fe.sup.+2, and 0.01?y?1. Exemplary layered double hydroxide hydrogels (LDH-gels) may comprise a hydrogel and at least one LDH. Exemplary hydrogels may comprise polyethylene (glycol) diacrylate (PEGDA) or polyacrylamide (PAAm). Exemplary LDH-gels may comprise at least one LDH comprising a compound of formula Mg.sub.4-yAlX.sub.y(OH).sub.2, wherein X is Mn.sup.+2, Cu.sup.+2, Zn.sup.+2, or Fe.sup.+2, and 0.01?y?1.

The disclosure discloses a method for recycling a lithium iron phosphate waste battery, and belongs to the technical field of battery recycling. In the method for recycling the lithium iron phosphate waste battery according to the disclosure, it takes a cathode material of the waste lithium iron phosphate battery as a main body, uses a lithium source, a ferric source and a phosphorus source to supplement lithium to the cathode material for repairing, and meanwhile, rebuilds a new lithium iron phosphate coating layer containing a carbon layer cross-linked structure on a surface of the cathode material to realize regeneration of the lithium iron phosphate The disclosure also provides a regenerated lithium iron phosphate/C cathode material prepared by the recycling method.