2109 results about "Lithium carbonate" patented technology

The invention belongs to the technical field of enamel glaze preparation, and particularly relates to a high-temperature-resistant compact enamel glaze preparation method, which comprises: 1, enamel frit preparation: mixing 45-65% by mass of silicon dioxide, 10-15% by mass of anhydrous borax, 5-10% by mass of sodium carbonate, 2-6% by mass of lithium carbonate, 2-6% by mass of calcium carbonate, 2-6% by mass of strontium carbonate, and 3-6% by mass of ice crystal to form a batch, melting at 1300 DEG C for 2-3 hours, carrying out water quenching to prepare an enamel material, drying, and sieving with a 200-mesh sieve to obtain enamel frit powder; step 2, preparing enamel glaze slip, namely mixing and ball-milling 40-55% of enamel frit powder, 15-30% of 316 # stainless steel powder, 5.5-10% of clay suspending agent and 25-50% of water in percentage by mass to obtain the enamel glaze slip; and step 3, enamel coating and firing. The enamel coating has excellent high temperature resistance and corrosion resistance and long service life, and the preparation process is simple in requirement, simple and convenient to operate and suitable for industrial production.

The invention discloses a preparation method of a high-compaction-density lithium iron phosphate material, through grading of large and small particle lithium iron phosphate, optimization of a sintering process and reasonable selection of a carbon source and a titanium dopant, the compaction density and the electrochemical performance of the material are remarkably improved, and the preparation method specifically comprises the following steps: mixing iron phosphate, lithium carbonate, the carbon source and auxiliary materials; the preparation method comprises the following steps: carrying out coarse grinding and fine grinding, respectively preparing large-particle lithium iron phosphate and small-particle lithium iron phosphate (a material A and a material B) by adopting spray drying and high-temperature calcination processes, mixing the material A and the material B according to a ratio, adding auxiliary materials, grinding, further carrying out spray drying, calcining and crushing to obtain a final lithium iron phosphate product, and the maximum compaction density of the prepared material can reach 2.712 g / cm < 3 >. According to the present invention, the maximum 1C discharge specific capacity can achieve 140.5 mAh / g, the maximum 1C 3.2 V discharge platform retention rate is 91.4%, and the prepared lithium ion battery negative electrode material has characteristics of excellent conductivity, high discharge capacity and good cycle stability, and is suitable for power batteries and energy storage batteries.

The invention provides a self-leveling rapid repair mortar based on a steel slag solid waste cementing material and a preparation method thereof, the self-leveling rapid repair mortar comprises the following components in parts by mass: 100 parts of a self-leveling rapid repair mortar cementing material: 20-32 parts of steel slag powder, 20-30 parts of slag powder, 10-23 parts of raw ash, 10-15 parts of desulfurized gypsum, 5-8 parts of silica fume, and 8-25 parts of rapid hardening sulphoaluminate cement; the fine aggregate comprises 50 parts of quartz sand and 50 parts of steel slag aggregate; 0.3 to 0.7 part of a polyether defoaming agent, 0.05 to 0.25 part of lithium carbonate and 6 to 12 parts of a polycarboxylic acid water reducing agent; and 25-28 parts of water. According to the self-leveling rapid repair mortar based on the steel slag solid waste cementing material, on the basis of an alkali excitation synergistic sulfate excitation mechanism, the solid waste materials such as the steel slag powder, the slag powder, the raw ash and the desulfurized gypsum are utilized, and through proportioning optimization, the self-leveling rapid repair mortar which can open traffic within 2 hours and has the compressive strength gt within 28 days is prepared; the bonding strength is gt; the self-leveling mortar for rapidly repairing the cement concrete pavement has the advantages of self-leveling, no shrinkage of later strength and excellent durability.

The invention discloses a method for recycling lithium in a lithium battery, and belongs to the field of lithium battery recycling. The method comprises the following steps: decomposing the lithium battery, and performing pyrolysis treatment at 200-500 DEG C to obtain a slag material; the slag charge is placed in a composite leaching agent, the pH is adjusted to 1.5-2.5, lithium in the slag charge is leached out, and a leaching solution is obtained; the composite leaching agent comprises oxalic acid, an amino acid ligand, persulfate and fluorine ions; adjusting the pH value of the leaching solution to 5.5-6.2, adding an extracting agent into the leaching solution, extracting lithium ions in the leaching solution, and separating to obtain a lithium-rich organic phase and lithium-containing waste liquid; the extraction agent comprises crown ether and organophosphate; and the lithium-rich organic phase is subjected to back extraction, so that lithium ions are released from the organic phase, a lithium-rich back extraction solution is obtained, a carbonate solution is added into the lithium-rich back extraction solution, and lithium carbonate precipitates are obtained. According to the method for recycling the lithium in the lithium battery, selective leaching of the lithium can be achieved, and the comprehensive yield of the lithium in the lithium battery is increased.

The invention discloses a method for extracting lithium from a salt lake and an extraction device. The method for extracting lithium from the salt lake provided by the invention comprises the following steps: salt lake brine is subjected to aluminum adsorbent adsorption, ultrafiltration impurity removal, multi-stage nanofiltration magnesium and boron removal, reverse osmosis concentration, ultrafiltration softening deep magnesium removal, resin magnesium and boron removal, MVR evaporation and other technological processes, and a battery-grade lithium carbonate product is obtained. According to the method, the membrane separation technology serves as a core, resin and an evaporation system serve as auxiliary materials, deep separation of magnesium and lithium in the salt lake brine is achieved, the boron removal rate and the lithium recovery rate are high, meanwhile, recycling of water resources is guaranteed, and the whole process has the advantages of being controllable, high in automation degree, low in production cost, small in pollution, high in water recovery rate and suitable for industrial production. The method can be applied to large-scale production of salt lake lithium extraction.

The invention discloses a lithium manganese iron phosphate positive electrode material with a core-shell structure, which is prepared by the following steps: mixing a manganese source, an iron source, a phosphorus source, lithium carbonate and a carbon source, grinding and drying to prepare a pre-sintered material; then carrying out gas crushing on the pre-sintered material to obtain a pre-gas crushed material, and carrying out heat preservation at the temperature of 200-600 DEG C; putting the pre-gas crushed material subjected to heat preservation into an iron salt solution for quenching reaction to obtain iron compound coated lithium manganese iron phosphate; and finally, mixing the lithium iron manganese phosphate coated with the iron compound, a lithium source, a phosphorus source and a carbon source, grinding, drying, and carrying out secondary calcination to obtain the lithium iron manganese phosphate material with the core-shell structure. During preparation of the lithium manganese iron phosphate positive electrode material, a lithium manganese iron phosphate pre-sintered body and an iron salt solution are subjected to a quenching reaction to form an iron compound coated lithium manganese iron phosphate pre-sintered body, and then the iron compound coated lithium manganese iron phosphate pre-sintered body and other raw materials of lithium iron phosphate are subjected to a secondary calcination reaction to generate the composite positive electrode material with a core-shell structure. A coating structure is formed, the reaction between manganese and electrolyte is reduced, the dissolution of manganese is inhibited, the Gingtaler effect of manganese is relieved, and the stability of the material is improved; and the material has the advantages of high energy density, high power density, excellent cycle performance and strong core-shell interface bonding force.

The invention discloses a waste battery lithium iron phosphate positive electrode black powder recovery method which comprises the following steps: S1, activating and roasting positive electrode black powder to obtain pretreated black powder, and mixing and ball-milling the pretreated black powder, an oxidizing agent and an activating solvent to obtain pre-oxidized black powder; s3, the pre-oxidized black powder and an inorganic solvent are mixed for a leaching reaction, and mother liquor A and iron phosphate slag are obtained; s4, adding a pH regulator into the mother liquor A to remove impurities so as to obtain mother liquor B; s5, mixing and purifying the iron phosphate slag and phosphoric acid to obtain crude iron phosphate, washing the crude iron phosphate with water, and adding a complexing agent for further purification to obtain high-purity iron phosphate; and S6, concentrating the mother liquor B to obtain concentrated mother liquor C, and introducing carbon dioxide into the concentrated mother liquor C to precipitate lithium to obtain the battery-grade lithium carbonate. According to the process, iron, lithium, phosphorus and other elements in the positive electrode black powder are efficiently separated and recycled, low-acid or acid-free green leaching of lithium is achieved, the lithium leaching rate is larger than or equal to 98.0%, and the purity of obtained iron phosphate is larger than or equal to 99.3%; the purity of lithium carbonate is greater than or equal to 99.0%.

The invention discloses a method for preparing a composite positive electrode material by using a waste battery, and belongs to the technical field of battery recovery. The method comprises the following steps: discharging, disassembling and sorting a waste lithium iron phosphate battery to obtain a positive plate, carrying out water treatment, separating from an aluminum foil to obtain a waste lithium iron phosphate sheet, adding sodium hypochlorite, tetraethoxysilane, deionized water and hydrochloric acid, stirring to obtain SiO2-coated iron phosphate precipitate particles and a lithium-containing solution, adding sodium hydroxide into the lithium-containing solution to adjust the pH value, and carrying out solid-liquid separation to obtain the lithium-ion battery cathode material. Adding sodium carbonate, heating and drying to obtain lithium carbonate precipitate. And adding a carbon source and alcohol into the SiO2-coated iron phosphate precipitate particles and lithium carbonate, carrying out ball milling, taking out, drying, and calcining in a protective atmosphere to obtain the positive electrode composite material. Compared with the prior art, according to the prepared positive electrode composite material, material particles contain a lithium silicate network, so that the specific discharge capacity of a battery material is effectively improved. The method is simple in process and suitable for comprehensive utilization of waste batteries.

The invention belongs to the technical field of solid-state battery materials, and discloses an inorganic solid-state electrolyte lanthanum lithium zirconate surface interface non-metallic element doped modified material using a plasma technology and a preparation method and application thereof, which can reduce the interface impedance of an electrolyte and improve the electrochemical performance of the electrolyte. By using the plasma technology, impurities such as lithium carbonate and the like on the surface of the inorganic solid electrolyte lanthanum lithium zirconate can be etched, a lithium-loving protective layer can be generated in situ on a surface interface, and the air stability of the electrolyte block is improved. According to the invention, multi-aspect modification can be realized by combining a plasma technology with a plurality of non-metallic element excitation sources, corresponding gain protection layers can be formed according to different requirements, and performance exertion of the battery in different fields is facilitated. When the inorganic solid electrolyte lanthanum lithium zirconate modified material obtained by the method disclosed by the invention is in contact with lithium metal to form a battery, the inorganic solid electrolyte lanthanum lithium zirconate modified material shows relatively low interface contact resistance and excellent cycling stability, and has a good application value.

The invention discloses a fluoride salt-free nitrate-free cast iron enamel semitransparent glaze as well as a preparation method and application thereof, and belongs to the technical field of enamel. The semitransparent glaze is prepared from quartz, anhydrous borax, sodium carbonate, potassium carbonate, calcium carbonate, potassium feldspar, zinc oxide, lithium carbonate, zirconium silicate, titanium dioxide, aluminum oxide, trisodium phosphate, antimony oxide, magnesium carbonate and barium carbonate according to a specific mass ratio. The preparation method comprises the steps of raw material mixing, high-temperature melting under a pure oxygen condition, wiredrawing detection, quenching and the like. The semitransparent glaze is completely free of fluoride salt and nitrate, the problems of fluoride emission and environmental protection equipment blockage are avoided from the source, the fluorine content of the product is not detected through detection, the product meets the requirements of European Union REACH regulations, meanwhile, the product has good porcelain surface, luster and low-temperature firing adaptability, and is suitable for cast iron matrixes, the firing temperature is 740-760 DEG C, and the firing time is 2-3 hours. The method can be used for producing green and environment-friendly enamel products.

The invention discloses a method for preparing a manganese iron phosphate precursor by recycling waste lithium manganese iron phosphate, and belongs to the technical field of lithium ion batteries. The invention provides a method for preparing a manganese iron phosphate precursor by recycling waste lithium manganese iron phosphate, which comprises the following steps: by taking waste lithium manganese iron phosphate battery powder as a raw material, carrying out acid dissolution and filtration to remove graphite and part of impurities; adjusting the pH value of the filtrate to obtain a lithium-ion-rich solution and a ferromanganese precipitate, and adding sodium carbonate into the lithium-ion-rich solution for concentration and crystallization to obtain battery-grade lithium carbonate; carrying out acid dissolution on the ferromanganese precipitate, removing copper and aluminum impurities in the solution, adjusting the ratio of ferromanganese to phosphorus, and mixing with liquid caustic soda in a nitrogen atmosphere to obtain a ferromanganese phosphate precursor; according to the method, the problems of incomplete recovery and insufficient impurity removal of the manganese iron phosphate lithium battery are solved, the battery-grade lithium carbonate and the manganese iron phosphate precursor are prepared during recovery, the value of the recovered product is improved, and the production requirement of the lithium ion battery is met.

Disclosed is a method for short-range recovery of a valuable metal from a waste ternary lithium battery. By means of the steps of nickel and cobalt precipitation by a two-stage chemical precipitation method and trisodium phosphate-based lithium precipitation, the problem in the prior art of high content of impurities in lithium carbonate is solved and high-quality lithium carbonate is obtained; in addition, the whole process is carried out in a normal pressure environment. Compared with the complex process of recovering nickel, cobalt, and manganese metals by an extraction + MVR evaporative crystallization method and recovering a lithium metal after MVR concentration, the demand of a waste ternary lithium battery recovery process for energy consumption and the pollution of the waste ternary lithium battery recovery process to the environment are greatly reduced, and industrial production is facilitated.

The invention discloses a method for recovering lithium, nickel cobalt manganese composite hydroxide and aluminum copper powder from a waste ternary lithium ion battery pole piece. The method comprises the following steps: treating waste pole pieces of a ternary plant or a mixture of positive and negative pole pieces by using a Fenton technology, leaching by using a mixed ferric salt solution, and filtering to obtain lithium-containing leachate and slag; adjusting the pH value of the leachate, oxidizing and filtering to obtain a purified solution and ferric hydroxide precipitate, and adding the purified solution and a lithium hydroxide solution into a reactor for coprecipitation to obtain a deeply purified solution and the nickel-cobalt-manganese composite hydroxide. And dissolving the ferric hydroxide precipitate with dilute acid, adding a reducing agent to generate a ferrous salt solution, and returning the ferrous salt solution for Fenton reaction and leaching reaction. And adding the sodium carbonate saturated solution into the deep purification solution, and crystallizing and precipitating to obtain the battery-grade lithium carbonate. And performing hydrodynamic screening on the leaching residues to obtain an aluminum-copper mixture and graphite residues, and performing grinding and specific gravity separation on the aluminum-copper mixture to obtain high-purity aluminum powder and copper powder. According to the method, the iron salt is directly leached from the pole piece, the used iron salt can be recycled, and the method is suitable for large-scale recovery of the waste ternary lithium ion battery.

The invention relates to the technical field of lithium iron phosphate batteries, and particularly discloses purification equipment and a purification process for recycling lithium carbonate from lithium iron phosphate batteries, the purification equipment comprises a crushing box and a grinding box, the grinding box is arranged below the crushing box, two crushing rollers are mounted in the crushing box, and a fixing frame is mounted on the outer wall of the crushing box; a filter box is arranged in the fixing frame, the top of the fixing frame is connected with a first moving frame through a telescopic mechanism, a second moving frame is installed in the first moving frame, two placing frames are placed above the second moving frame, and a processing mechanism is arranged at the top of the crushing box. According to the waste battery crushing equipment, through the arranged processing mechanism, the batteries can be extruded in advance before being crushed, so that the subsequent crushing process is easier to carry out, the energy consumption of the crushing equipment can be reduced, the crushing efficiency can be improved, the treatment time of the waste batteries can be shortened, and the generation of dust can be reduced; and positive significance is brought to preparation and purification of lithium carbonate.

The invention relates to a method for preparing a pyrochlore oxyfluoride solid electrolyte by a one-step solid phase method, which comprises the following steps: uniformly mixing lithium carbonate (Li2CO3), lanthanum oxide (La2O3), niobium pentoxide (Nb2O5) and lithium fluoride (LiF), and carrying out high-temperature one-time sintering under protective gas to synthesize a Li2-xLa (1 + x) / 3Nb2O6F (LLNOF solid electrolyte material. The synthesis route is optimized, a single fluorine source is used, and the types of raw materials are reduced; according to the method, secondary sintering is not needed, the pure-phase electrolyte powder can be obtained by adopting one-step sintering synthesis, the steps are simple, the efficiency is high, the cost is reduced, and the resource consumption is reduced. According to the obtained LLNOF electrolyte material powder, the synthesis temperature ranges from 900 DEG C to 1100 DEG C, heating to 1100 DEG C or above is not needed, the requirement for heating equipment is low, large-scale mass production can be conducted, the sample yield is large, and energy consumption is low. Required synthesis equipment is simple and easy to obtain, and the ionic conductivity is good. The lithium ion conductor with high conductivity and stability in air is synthesized through a one-step method.

The invention relates to the technical field of membrane separation and resource recovery, and discloses a bipolar membrane electrodialysis device for synchronously capturing carbon dioxide, extracting lithium and producing lithium carbonate. The device utilizes a selective bipolar membrane electrodialysis system to extract lithium ions from liquid resources such as spodumene leachate, brine, oil and gas field wastewater, seawater and the like, and converts the lithium ions into lithium hydroxide. And meanwhile, introducing flue gas containing carbon dioxide into the generated lithium hydroxide solution by using a gas disperser to generate lithium carbonate. Therefore, mineralization capture of carbon dioxide in the flue gas, extraction of lithium ions in liquid resources such as spodumene leachate, brine, oil and gas field wastewater and seawater and production of lithium carbonate are synchronously realized, waste is treated by waste, and the method has the advantages of simple process, high lithium ion yield, short period, environmental friendliness, no pollution, continuous production and the like, and is suitable for industrial production. The method has important significance on carbon dioxide capture, lithium resource recovery and development of the new energy industry.

The invention provides a lithium precipitation mother liquor lithium recovery method based on countercurrent centrifugal extraction. The method comprises the following steps: S1, pretreating a lithium precipitation mother liquor to obtain a lithium-containing pre-extraction solution; s2, conveying the lithium-containing pre-extraction liquid to a centrifugal extraction system, fully mixing the lithium-containing pre-extraction liquid with an organic phase, and sequentially carrying out multi-stage countercurrent centrifugal extraction; performing phase splitting to obtain raffinate and a lithium-loaded organic phase; s3, the lithium-loaded organic phase enters a washing section to be subjected to multi-stage countercurrent centrifugal washing; s4, performing multi-stage countercurrent centrifugal reverse extraction on the washed lithium-loaded organic phase to obtain a lithium-rich solution; and S5, synthesizing the lithium-rich solution and a sodium carbonate solution to obtain the battery-grade lithium carbonate. The lithium recovery method has the characteristics of rapidness, high efficiency, low equipment investment, small occupied area, less extraction agent consumption and short process flow.

The invention belongs to the field of grouting materials, and discloses a composite grouting material as well as a preparation method, a construction method and application thereof. The composite grouting material comprises the following components: sulphoaluminate cement clinker powder, Portland cement clinker powder, a reinforcing agent, a coagulant and a modifier, the reinforcing agent comprises superfine mineral powder, superfine fly ash, silica fume and calcium sulfate whiskers; the coagulant comprises alumina clinker powder, calcium hydroxide, lithium carbonate and aluminum hydroxide; the modifier comprises a shrinkage reducing agent, a thickening agent, a water reducing agent and a retarder. The composite grouting material has the advantages of being good in pumpability, short in gelation time, free of plastic shrinkage, high in early strength, good in volume stability, high in durability, appropriate in price, environmentally friendly, free of toxicity and the like, and the requirement for rapid grouting maintenance is met in the subway operation window period.

A method including pretreating ground lithium-containing ceramics to form alkali coated ceramics, leaching the alkali coated ceramics to form a leachate comprising a filtrate and a solid residue, preferentially extracting lithium from the filtrate to form a lithium rich solution and a raffinate, precipitating a crude lithium carbonate from the lithium rich solution and purifying the crude lithium carbonate to produce a battery grade lithium carbonate. A method including leaching a slurry comprising lithium-containing ceramics, water, a strong base, and an alkaline earth metal oxide / hydroxide at a pressure ranging from 0 to 1450 psi and at a temperature ranging from 100 to 500°C to form a leached slurry comprising a liquid filtrate and a solid residue, processing the liquid filtrate to recover a lithium-rich organic solution, and processing the lithium-rich organic solution to produce a battery-grade lithium compound and sodium sulfate.

The invention provides application of poly-2-acrylamide-2-methylpropanesulfonic acid in removal of residual lithium on the surface of a high-nickel NCM ternary material, and relates to the technical field of surface treatment of the high-nickel NCM ternary material. The method aims at solving the problem that an existing method for removing lithium carbonate on the surface of an NCM material through high-temperature calcination or high-concentration ethyl alcohol soaking and cleaning has adverse effects on the structure and performance of the high-nickel NCM ternary material. According to the invention, the cleaning agent using poly-2-acrylamide-2-methylpropanesulfonic acid as a main component is provided for cleaning the residual lithium of the high-nickel NCM ternary material, and verification proves that the high-nickel NCM ternary material can be effectively prevented from being damaged by existing high-temperature calcination and high-concentration ethanol soaking and cleaning treatment, and meanwhile, the electrochemical performance of the high-nickel NCM ternary material is remarkably improved.

The invention provides a method for preparing battery-grade lithium carbonate by using waste lithium iron phosphate batteries. The method comprises the following steps: step 1, discharging, disassembling and crushing the waste lithium iron phosphate batteries to obtain lithium iron phosphate battery powder; 2, adding a sulfuric acid solution and hydrogen peroxide into the lithium iron phosphate battery powder, and filtering after reaction to obtain a lithium-containing solution and ferrophosphorus slag; 3, calcium hydroxide and sodium hydroxide are sequentially added into the lithium-containing solution to remove impurities, then sodium carbonate is added, and a purified lithium solution is obtained through filtering; 4, adding an organic solvent into the purified lithium solution, fully stirring, and filtering to obtain a sodium sulfate crystal substance and an organic mixed solution; and 5, adding sodium carbonate into the organic mixed solution, fully reacting, filtering, and washing to obtain the battery-grade lithium carbonate.

The invention relates to a process for recycling and regenerating a waste lithium iron phosphate positive electrode material by using a specific chelating agent. The method comprises the following steps: carrying out heat treatment on a waste lithium iron phosphate positive electrode material, putting separated waste lithium iron phosphate powder into a ball milling tank, adding organic acid and a chelating agent, and carrying out ball milling; after the ball milling is finished, adding hydrogen peroxide, uniformly stirring and mixing, adjusting the pH value to 2-3 by using nitric acid, and filtering to obtain a filter cake which is iron phosphate; adding saturated sodium carbonate into the filtrate, precipitating, and recovering lithium carbonate; putting the iron phosphate, the lithium carbonate, the iron source, the lithium source and the phosphorus source in the step S3 into a ball mill for ball milling, and performing high-temperature solid-phase sintering after ball milling to obtain a regenerated lithium iron phosphate material; the chelating agent disclosed by the invention is prepared from (9ci)-2-(2-propenyl)-1-cyclopentene-1-carboxylic acid, 2-mercaptobenzimidazole carboxylic acid, an ethylene boric anhydride pyridine complex and potassium persulfate. The regenerated lithium iron phosphate material prepared by the method has excellent electrochemical performance.

The invention relates to the technical field of retired ternary power battery recovery, and particularly discloses a method for preferentially extracting lithium and recovering valuable metals from a retired ternary lithium battery and application of the method. According to the method, the traditional process is broken through the preferential lithium extraction, and efficient recovery of lithium, Ni, Co and Mn is realized by utilizing'fast-medium-slow 'multi-stage cooperation of a composite reducing agent and accurate adaptation of roasting and leaching parameters, so that the method has the advantages of low cost, high efficiency, low energy consumption and the like, and is suitable for large-scale industrial production. The method is low in energy consumption and environment-friendly, and is applied to resource recycling of the retired ternary lithium battery, and the precursor can be used for reproducing a positive electrode material or used for a catalytic material.

The invention relates to the technical field of preparation of lithium battery materials, and discloses a synthesis method of a low-cost battery-grade lithium dihydrogen phosphate raw material lithium phosphate. The synthesis method comprises the following steps: dissolving crude lithium sulfate in alkaline lithium phosphate lithium precipitation mother liquor; carrying out chemical precipitation on the filtered lithium sulfate solution to preliminarily remove calcium, and subsequently, deeply removing calcium and COD (Chemical Oxygen Demand) by sequentially using activated carbon and calcium removal resin to obtain a lithium sulfate finished solution; mixing the lithium sulfate completion liquid and the alkali liquid, freezing to-10 DEG C to-3 DEG C, and performing centrifugal separation to obtain a lithium sulfate freezing liquid; and reacting the refrigerating fluid with a dilute phosphoric acid solution to precipitate lithium phosphate, stirring, washing and centrifuging the filtered crude product lithium phosphate, and drying to obtain the battery-grade lithium dihydrogen phosphate raw material lithium phosphate. The lithium phosphate prepared at low cost is used for replacing battery-grade lithium carbonate, lithium hydroxide and the like as a lithium source for producing the lithium dihydrogen phosphate, so that the production cost of the battery-grade lithium dihydrogen phosphate can be effectively reduced, the lithium phosphate mother liquor is recycled, and the problem of treating a large amount of wastewater caused by other methods is solved.

The invention provides a preparation method and application of lithium sulfide. The preparation method comprises the following steps: reacting a lithium source with a sulfur source; the lithium source is a solid lithium-containing substance with the purity of 99% or above and the whiteness of 86 or above; the solid lithium-containing substance is selected from one or more of anhydrous lithium hydroxide, lithium hydroxide monohydrate, lithium carbonate, lithium chloride, lithium bromide and lithium nitrate. According to the method, a solid lithium-containing substance with the purity of 99% or above and the whiteness of 86 or above is used as a lithium source and reacts with a sulfur source, and the ionic conductivity value of the Li6PS5Cl solid electrolyte prepared from the obtained lithium sulfide is stable. Experimental results show that the ionic conductivity can stably reach more than 2mS / cm.

The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium manganate positive electrode material, a preparation method thereof and a lithium battery, and the method comprises the following steps: adding a manganese sulfate solution, a precipitator and a complexing agent into a reaction kettle in a parallel flow manner, reacting under a first preset reaction condition, and introducing a first oxidant while reacting to obtain a mixed solution; concentrating the mixed solution to preset solid content, and adding a curing agent for curing reaction to obtain manganous-manganic oxide slurry; adding a manganese sulfate solution, a precipitant and a complexing agent into the reaction kettle in a parallel flow manner again, reacting with the manganous-manganic oxide slurry under a second preset reaction condition, introducing a second oxidizing agent while reacting to obtain a composite manganese oxide mixed solution, and filtering, washing and drying to obtain a composite manganese oxide; the composite manganese oxide and lithium carbonate are mixed, calcined, crushed and graded to obtain the lithium manganate positive electrode material, so that the electrochemical performance of the lithium manganate positive electrode material is improved.

The invention relates to the technical field of extraction and utilization of electrolytic aluminum lithium-containing waste, in particular to a method for selectively extracting lithium from electrolytic aluminum waste. The method comprises the following steps: (1) coarsely crushing the electrolytic aluminum waste; (2) calcining or combusting the electrolytic aluminum waste to remove carbon; (3) carrying out two-stage lithium leaching on the carbon-removed filter residues by controlling leaching conditions; (4) performing two-stage impurity removal on the lithium leachate; and (5) concentrating and denitrifying the impurity-removed liquid, precipitating lithium, carbonizing and crystallizing to prepare the battery-grade lithium carbonate. According to the method, after carbon in the electrolytic aluminum waste is removed through a calcination or combustion method, lithium in the waste aluminum slag is dissolved out into the leaching solution by controlling the leaching conditions, and aluminum, iron, sodium and most fluorine in the waste aluminum slag are not dissolved out and are left in the leaching slag. And performing simple impurity removal, concentration and denitration on the leachate to prepare the battery-grade lithium carbonate. The method is simple in process, low in reagent consumption and high in lithium extraction rate.