A method of making a proppant-gel matrix comprising: a) hydrating a gelling agent to form a hydrated gelling agent; b) adding a basic compound to the hydrated gelling agent to form a basic hydrated gelling agent having a pH in the range of 11.5 to 14.0; c) mixing the basic hydrated gelling agent and a proppant to form a basic hydrated gelling system; and d) adding a crosslinking agent to the basic hydrated gelling system to form the proppant-gel matrix, is disclosed. The proppant-gel matrix can then be used as a fracturing fluid in a hydraulic fracturing process.

A lithium transition metal phosphate material comprising lithium iron phosphate doped with very precise amounts of aluminium dopant, the material having formula Li.sub.yFe.sub.1-xAl.sub.xPO.sub.4, in which 0.8≤y≤1.2 and 0.0120≤x≤0.0180. When x is within this range, the capacity of the material can be improved, and good or excellent distribution of aluminium in the lithium metal phosphate is observed.

Process for the production of a compound comprising potassium phosphite comprising the steps of (a) reacting carboxylic acid of the formula R—(C(═O)OH).sub.n with phosphorous trichloride (PCl.sub.3) towards a mixture comprising phosphorous acid (H.sub.3PO.sub.3) and acid chloride of the formula R—(C(═O)Cl).sub.n; wherein R is a linear or branched alkyl or alkanediyl group with 1-20 carbon atoms and n is 1 or 2, (b) subjecting said mixture to a separation step, thereby obtaining (i) a fraction comprising crude phosphorous acid (H.sub.3PO.sub.3) and (ii) a fraction comprising acid chloride, (c) combining water, a potassium compound selected from KOH, KHCO.sub.3 and K.sub.2CO.sub.3, and the fraction comprising crude phosphorous acid, thereby forming an aqueous solution comprising potassium phosphite, and (d) removing organic compounds from said aqueous solution.

There is provided a solid electrolyte including at least one layer with no nitrogen and which includes Li.sub.xPO.sub.yS.sub.z, with 0<z≤3, 2.1≤x≤2.4, and 1≤y≤4. A battery including the electrolyte, and a method for producing the electrolyte, are also provided.

Provided is a cathode active material including a core including a compound represented by Formula 1; and a coating layer including a phosphorus-containing compound disposed on a surface of the core:
Li.sub.aZr.sub.αW.sub.βM.sub.1−α−βO.sub.2−bS.sub.b  Formula 1 In Formula 1, M, Zr, W, a, α, β, and b are the same as defined in relation to the present specification.

Disclosed is lithium iron phosphate having an olivine crystal structure, wherein the lithium iron phosphate has a composition represented by the following Formula 1 and carbon (C) is coated on the particle surface of the lithium iron phosphate containing a predetermined amount of sulfur (S).
Li.sub.1+aFe.sub.1−xM.sub.x(PO.sub.4−b)X.sub.b  (1) (wherein M, X, a, x, and b are the same as defined in the specification).

Disclosed is lithium iron phosphate having an olivine crystal structure, wherein the lithium iron phosphate has a composition represented by the following Formula 1 and carbon (C) is coated on the particle surface of the lithium iron phosphate containing a predetermined amount of sulfur (S).
Li.sub.1+aFe.sub.1−xM.sub.x(PO.sub.4−b)X.sub.b  (1) (wherein M, X, a, x, and b are the same as defined in the specification).

Nanosized lithium phosphate sulfide solid state electrolytes are synthesized by a facile method using ethyl acetate as the solvent. SSE compositions comprising nanosized lithium phosphate sulfide synthesized using the methods include particles having an average diameter of from 50 nm to 1000 nm. The nanosized lithium phosphate sulfide has a formula Li.sub.xP.sub.yS.sub.z, wherein 3≤x ≤7, 1≤y≤3, and 4≤z≤11.

The present invention relates to a lithium compound manufacturing method comprising the steps of heat treatment of lithium-containing ore; roasting the heat-treated ore with sulfuric acid to prepare an acid product; mixing the acid product with leaching water to prepare a leachate; purifying the leachate; and adding a phosphorus supply material and a basic material to the purified leachate to obtain a solid lithium phosphate.

The present invention relates to a lithium compound manufacturing method comprising the steps of heat treatment of lithium-containing ore; roasting the heat-treated ore with sulfuric acid to prepare an acid product; mixing the acid product with leaching water to prepare a leachate; purifying the leachate; and adding a phosphorus supply material and a basic material to the purified leachate to obtain a solid lithium phosphate.