Anisotropic zinc phosphate particles and zinc metal mixed phosphate particles having an orthorhombic crystal structure and a platelet-shaped particle morphology are obtained from a composition comprising at least one phosphate compound; at least one zinc compound and at least one chelate complexing agent having at least two oxygen-containing groups and at least one solvent.

The present invention provides a process for the preparation of phosphor aerogel of uniform size having high porosity, low density; high thermal insulation and high luminescence, which is useful for various applications like lighting, display, sensing and other applications.

More specifically, the present invention provides a simple and versatile process for the formation of monolithic gel, at room temperature, which on further drying at supercritical temperature and pressure result in dry aerogel. Further, annealing under mild reduced atmosphere from 1000°-1400° C. not only retains the porous network with uniform size particles but also crystallizes to form a phosphor aerogel having brightest luminescence with bulk density as low as 100 kg m-3, and strong enough to support a weight much higher than its own weight.

The present invention provides a cost-effective method of synthesizing phosphate salt of a metal such as Fe and Mn that can be used for electrode active material of a lithium secondary battery. A precipitation reaction is first carried out to produce a solid salt of the metal having a lower valence value, e.g. Fe(II) and Mn(II). The solid salt is then purified before it is oxidized to form the target phosphate salt of the metal having a higher valence value, e.g. Fe(III) and Mn(III). The invention exhibits numerous technical merits such as easier operation, higher purity, and less consumption of washing water, among others.

A lithium ion-conducting oxide including at least lithium, tantalum, M1, phosphorus, and oxygen as constituent elements. M1 is at least one metal element selected from elements of the Group 4, the Group 5, the Group 6, the Group 13, and the Group 14 (provided that tantalum is excluded), a ratio of number of atoms of each constituent element of lithium, tantalum, M1, phosphorus, and oxygen is 1:2−x:x:1:8, wherein x is more than 0 and less than 1, and the lithium ion-conducting oxide contains a monoclinic crystal. Also disclosed is a lithium-ion secondary battery including the lithium ion-conducting oxide.

It is an object to provide a manufacturing method for a large amount of positive electrode active material with few variations, having a highly uniform surface condition, micro-size, and high performance. An aqueous solution of a compound, which becomes the source material for the positive electrode active material, is put in an airtight container and irradiated with microwaves, thus heating while water in the airtight container is evaporated and a high pressure is formed in the air tight container. A large amount of micro-sized positive electrode active material having a highly uniform surface condition can be formed. A compound, which becomes the source material for the positive electrode active material, is put in an airtight container and irradiated with microwaves, thus heating while water in the airtight container is evaporated and a high pressure is formed in the air tight container.

It is an object to provide a manufacturing method for a large amount of positive electrode active material with few variations, having a highly uniform surface condition, micro-size, and high performance. An aqueous solution of a compound, which becomes the source material for the positive electrode active material, is put in an airtight container and irradiated with microwaves, thus heating while water in the airtight container is evaporated and a high pressure is formed in the air tight container. A large amount of micro-sized positive electrode active material having a highly uniform surface condition can be formed. A compound, which becomes the source material for the positive electrode active material, is put in an airtight container and irradiated with microwaves, thus heating while water in the airtight container is evaporated and a high pressure is formed in the air tight container.

The epsilon polymorph of vanadyl phosphate, ε-VOPO.sub.4, made from the solvothermally synthesized H.sub.2VOPO.sub.4, is a high density cathode material for lithium-ion batteries optimized to reversibly intercalate two Li-ions to reach the full theoretical capacity at least 50 cycles with a coulombic efficiency of 98%. This material adopts a stable 3D tunnel structure and can extract two Li-ions per vanadium ion, giving a theoretical capacity of 305 mAh/g, with an upper charge/discharge plateau at around 4.0 V, and one lower at around 2.5 V.

There is provided a modified zirconium phosphate tungstate which effectively suppresses the elution of phosphorus ions even when it contacts with water, can develop the performance excellent as a negative thermal expansion material, and can be dispersed in a polymer compound such as a resin, and use of which enables a low-thermal expansive material containing a negative thermal expansion filler to be well produced. The surface of a zirconium phosphate tungstate particle is coated with an inorganic compound containing one or two or more elements (M) selected from Zn, Si, Al, Ba, Ca, Mg, Ti, V, Sn, Co, Fe and Zr. The BET specific surface area of the zirconium phosphate tungstate particle is preferably 0.1 m.sup.2/g to 50 m.sup.2/g.

An all solid battery includes: a solid electrolyte layer including phosphoric acid salt-based solid electrolyte; a first electrode that is formed on a first main face of the solid electrolyte layer; and a second electrode that is formed on a second main face of the solid electrolyte layer, wherein a D50% grain diameter of crystal grains of the phosphoric acid salt-based solid electrolyte is 0.5 μm or less, wherein a D90% grain diameter of the crystal grains is 3 μm or less.

A method for producing a lithium iron phosphate precursor by using a retired lithium iron phosphate battery as a raw material is provided, which includes steps of: soaking a battery cell in acid, performing electrolysis to reclaim copper, oxidizing ferrous iron, precipitating iron phosphate, and precipitating lithium carbonate. After precipitation is completed, performing one-step reclaim to obtain the lithium iron phosphate precursor.