A method of producing electrode active materials includes generating a source material of titanium (Ti) and a source material of iron (Fe) from an ilmenite, and performing a operation to the source material of Fe and the source material of Ti. The operation includes determining a content of Fe or Ti in the source material of Fe or Ti, preparing an intermediate mixture having the source material of Fe or Ti and other required source materials, ball-milling and drying the intermediate mixture, and sintering the intermediate mixture to form the electrode active materials.

The present application belongs to the technical field of battery materials. Disclosed are a doped iron (III) phosphate, a method for preparing same, and use thereof. The chemical formula of the doped iron (III) phosphate is (Mn.sub.xFe.sub.1x)@FePO.sub.4.Math.2H.sub.2O, wherein 0<x<1. According to the present application, ferromanganese phosphate is used as a template agent for preparing the doped iron (III) phosphate. The doped iron (III) phosphate is regular in morphology and good in fluidity, facilitates washing and conveying, and can improve the electrochemical performance of the subsequently prepared LiFePO.sub.4/C. When the doping amount of Mn is 11000 ppm, the specific discharge capacity of LiFePO.sub.4/C at room temperature at 0.1 C rate can reach 165 mAh/g; the retention rate of the discharge capacity of 1000 cycles at 45 C. at 1 C rate can reach 97.4%; and at a low temperature of 15 C. the specific discharge capacity at 0.1 C rate is still 134 mAh/g.

A method for preparing mesoporous iron phosphate by induction of block copolymers is provided. The method comprises preparing a ferric salt solution having a certain concentration and evenly dispersing it into a dispersant, then evenly mixing a structure directing agent solution with a phosphorus source solution, next adding the mixed solution to the ferric salt solution while dropwise adding an oxidant and stirring to react, thus after ending the reaction, washing, drying and calcinating the reaction product to obtain mesoporous iron phosphate. It is achievable to treat the block copolymer acting as a structure directing agent by way of using diverse dispersants and acidifiers different in concentration and induce the disodium hydrogen phosphate dihydrate to react with ferric salt solution to prepare mesoporous iron phosphate, producing mesoporous iron phosphate with controllable different conformations and meeting the requirements of cathode materials for lithium-ion batteries in different application scenarios.

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.

A preparation method of an iron phosphate precursor for batteries is disclosed and includes steps of: (a) providing a phosphoric acid and an iron powder, wherein the iron powder has an apparent density of iron powder ranging from 2.3 g/cm.sup.3 to 2.6 g/cm.sup.3, and a particle size composed of a first particle-size range and a second particle-size range, the first particle-size range is greater than the second particle-size range, and a weight of the iron powder in the second particle-size range accounts between 10% and 30% of the total weight of the iron powder; (b) reacting the phosphoric acid with the iron powder to generate a first product; and (c) heat-treating the first product in an air or oxygen atmosphere to form the iron phosphate precursor.

A preparation method of an iron phosphate precursor for batteries is disclosed and includes steps of: (a) providing an iron powder, wherein the iron powder has an apparent density of iron powder ranging from 2.3 g/cm.sup.3 to 2.6 g/cm.sup.3, and a particle size composed of a first particle-size range and a second particle-size range, the first particle-size range is greater than the second particle-size range, and a weight of the iron powder in the second particle-size range accounts between 10% and 30% of the total weight of the iron powder; (b) providing a phosphoric acid to react with the iron powder to generate a first product; and (c) heat-treating the first product in an air or oxygen atmosphere to form the iron phosphate precursor.

The present disclosure discloses a porous iron phosphate and a preparation method thereof. The preparation method includes the following steps: (1) mixing a phosphorus-iron solution with an aluminum-containing alkaline solution to allow a co-precipitation reaction; (2) subjecting a reaction system obtained in step (1) to solid-liquid separation (SLS) to obtain a precipitate; (3) subjecting the precipitate obtained in step (2) to a reaction with phosphine under heating; (4) after the reaction is completed, cooling a product obtained in step (3), and soaking the product in a weak acid solution; and (5) subjecting a system obtained in step (4) to SLS to obtain a solid, and subjecting the solid to aerobic calcination to obtain the porous iron phosphate.

In one aspect, a lithium manganese iron phosphate material includes a core, and a material of the core is represented by a general formula of Li.sub.xMg.sub.yMn.sub.zFe.sub.aAl.sub.bPO.sub.4, where x is ranged from 1.008 to 1.05, y is ranged from 0 to 0.006, z is ranged from 0.4 to 0.6, a is ranged from 0.388 to 0.6, and b is ranged from 0 to 0.012.

The present invention relates to a process for forming or obtaining vivianite in or from a phosphorus-containing waterbody, sediment and/or sludge, to an apparatus for obtaining vivianite from a phosphorus-containing waterbody, sediment and/or sludge, and to the use of a composition comprising at least one alkaline earth metal peroxide and a magnetic separating apparatus for obtaining vivianite from a phosphorus-containing waterbody, sediment and/or sludge.

This method recycles iron phosphate slag, which is produced as waste during lithium iron phosphate battery recycling processes that contain leaching or crushing for the sole extraction of lithium. This method extracts aluminum phosphate, iron phosphate, and lithium phosphate from the waste slag. The recycling process comprises these steps: (a) extraction of aluminum phosphate through addition of sodium hydroxide; (b) removal of carbon additives, graphite and other organic compounds through solvation of solely lithium, iron, and phosphate compounds through addition of sulfuric acid; (c) precipitation of iron phosphate by addition of hydrogen peroxide; (d) extraction of lithium phosphate from the mother liquor; (e) recycling of mother liquor into water and sodium sulfate. This process wastes few chemicals while still having a high reclamation efficiency in terms of purity and quantity. Furthermore, due to its relatively low costs, the profit margin of this process is very good.