This method synthesizes low-cost, high-performance iron phosphate that can be used for producing lithium-ion battery cathodes. It has three main steps: (S1) the synthesis of a iron (II,III) phosphate solution by mixing waste iron oxide (FeO, Fe.sub.2O.sub.3), low purity iron powder, and sulfuric acid in an aqueous solvent, followed by the addition of phosphoric acid; (S2) the addition of hydrogen peroxide to the previous solution, followed by pH balancing chemicals to yield crude iron phosphate; and (S3) the stirring of the previous solution to precipitate iron (III) phosphate, followed by an aging step, a filtering step, a washing step, and a drying step to obtain iron phosphate, which may be in the form of a hydrate. This straightforward approach uses waste iron oxide to minimize costs, while still yielding a fairly pure iron phosphate with excellent capacity, cycling stability, and broad physical and chemical properties suitable for battery production.

A method for preparing nano iron phosphate with low sulfur content. The method may include: S1: mixing a phosphorus source and an iron source to obtain a raw material solution, then adding alkali and a surfactant, adjusting a pH, and stirring and reacting to obtain an iron phosphate dihydrate slurry, S2: adding phosphoric acid solution into the iron phosphate dihydrate slurry, adjusting the pH, heating and stirring for aging, and filtering to obtain iron phosphate dihydrate, S3: adding water into the iron phosphate dihydrate for slurrying, and grinding to obtain a ground slurry; and S4: adding the ground slurry into a washing solution to wash, carrying out solid-liquid separation, and calcining a solid phase to obtain the nano iron phosphate with low sulfur content.

An energy storage composition can be used as a new Na-ion battery cathode material. The energy storage composition with an alluaudite phase of A.sub.xT.sub.y(PO4).sub.z, Na.sub.xT.sub.y(PO4).sub.z, Na.sub.1.702Fe.sub.3(PO4).sub.3 and Na.sub.0.872Fe.sub.3(PO4).sub.3, is described including the hydrothermal synthesis, crystal structure, and electrochemical properties. After ball milling and carbon coating, the compositions described herein demonstrate a reversible capacity, such as about 140.7 mAh/g. In addition these compositions exhibit good cycling performance (93% of the initial capacity is retained after 50 cycles) and excellent rate capability. These alluaudite compounds represent a new cathode material for large-scale battery applications that are earth-abundant and sustainable.

An LFP electrode material is provided which has improved impedance, power during cold cranking, rate capacity retention, charge transfer resistance over the current LFP based cathode materials. The electrode material comprises crystalline primary particles and secondary particles, where the primary particle is formed from a plate-shaped single-phase spheniscidite precursor and a lithium source. The LFP includes an LFP phase behavior where the LFP phase behavior includes an extended solid-solution range.

The invention relates to a method and system for phosphate recovery from a stream such as waste flow, sewage or another sludge stream. The method comprises the steps of: providing an incoming stream comprising an initial amount of phosphate; dosing/controlling iron salt to the stream such that precipitates are formed in the stream, wherein the precipitates comprise vivianite like structures comprising more than 60% of the initial amount of phosphate in the incoming stream, and preferably also the steps of: separating the vivianite like structures from the stream; and recovering the phosphates from the separated vivianite like structures.

An LFP electrode material is provided which has improved impedance, power during cold cranking, rate capacity retention, charge transfer resistance over the current LFP based cathode materials. The electrode material comprises crystalline primary particles and secondary particles, where the primary particle is formed from a plate-shaped single-phase spheniscidite precursor and a lithium source. The LFP includes an LFP phase behavior where the LFP phase behavior includes an extended solid-solution range.

A preparation method of nano-scaled iron phosphate, includes the steps of: adding a surfactant and a polymer microsphere to an iron salt solution to obtain a mixed liquid; adding a phosphate solution to the mixed liquid for reaction to obtain an iron phosphate slurry; performing solid-liquid separation after removing the polymer microsphere from the iron phosphate slurry, drying and calcining the obtained solid to obtain a nano-scaled iron phosphate.

The present invention provides a method for preparing battery-grade anhydrous iron phosphate from liquid crude monoammonium phosphate, and belongs to the technical field of chemical industry production. In the present invention, ferrous sulfate solution and liquid crude monoammonium phosphate are used as raw materials, and ferrous iron is oxidized to ferric iron and separates out iron phosphate precipitate under the action of an oxidizing agent to obtain iron phosphate intermediate slurry; and then battery-grade anhydrous iron phosphate is finally obtained through solid-liquid separation, washing, aging, solid-liquid separation, washing, drying, dehydration and breaking up. The method provided by the present invention realizes the resource utilization of liquid crude monoammonium phosphate, has simple process and convenient operation and produces less waste water.

A preparation method of a lithium iron phosphate cathode material includes steps of (a) providing a phosphoric acid, an iron powder, a carbon source, wherein the phosphoric acid and the iron powder are reacted to produce a first product, and the first product is amorphous iron phosphate with chemical formula of a-FePO.sub.4.Math.xH.sub.2O (x>0); (b) providing a lithium salt mixture, wherein the lithium salt mixture includes a lithium hydroxide and a lithium carbonate; (c) grinding and mixing the first product, the carbon source, and the lithium salt mixture; (d) calcining the first product and the lithium salt mixture to produce a precursor, wherein the precursor has a formula of Fe.sub.3(PO.sub.4).sub.2.Math.8H.sub.2O+Li.sub.3PO.sub.4; and (e) calcining the precursor and the carbon source to obtain the lithium iron phosphate cathode material.

A recycling and reworking method of a lithium iron phosphate cathode material is disclosed and includes steps of: (a) providing a lithium iron phosphate recycled material; (b) oxidizing the lithium iron phosphate recycled material in an atmosphere at an oxidation temperature ranged from 300? C. to 400? C. for 1 hour to 5 hours to form a raw material powder composed of LiFePO.sub.4, Fe.sub.7(PO.sub.4).sub.6, Fe.sub.2O.sub.3 and a residual carbon ranged from 0.07 wt. % to 0.6 wt. %; (c) grinding the raw material powder; (d) adjusting the composition of the raw material powder to form a precursor, which has the molar ratio of Li:P=0.99?1.05:1, and the molar ratio of Fe:P=0.98?1.02:1, wherein a carbon source is added; and (e) heat-treating the precursor in an inert gas at a sintering temperature ranged from 500? C. to 800? C. for 8 hours to 12 hours to form a lithium iron phosphate regenerated material.