WO2022237393A1 - 磷酸铁锂的制备方法 - Google Patents

磷酸铁锂的制备方法 Download PDF

Info

Publication number
WO2022237393A1
WO2022237393A1 PCT/CN2022/085377 CN2022085377W WO2022237393A1 WO 2022237393 A1 WO2022237393 A1 WO 2022237393A1 CN 2022085377 W CN2022085377 W CN 2022085377W WO 2022237393 A1 WO2022237393 A1 WO 2022237393A1
Authority
WO
WIPO (PCT)
Prior art keywords
iron phosphate
source
lithium
preparation
sintering
Prior art date
Application number
PCT/CN2022/085377
Other languages
English (en)
French (fr)
Inventor
万江涛
张宁
张勇杰
刘满库
李子郯
Original Assignee
蜂巢能源科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 蜂巢能源科技股份有限公司 filed Critical 蜂巢能源科技股份有限公司
Priority to KR1020237043007A priority Critical patent/KR20240009446A/ko
Priority to EP22806363.2A priority patent/EP4209456A1/en
Publication of WO2022237393A1 publication Critical patent/WO2022237393A1/zh

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00—Phosphorus; Compounds thereof
    • C01B25/16—Oxyacids of phosphorus; Salts thereof
    • C01B25/26—Phosphates
    • C01B25/45—Phosphates containing plural metal, or metal and ammonium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1397—Processes of manufacture of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/40—Electric properties
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/80—Compositional purity
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the invention relates to the technical field of synthesis of lithium iron phosphate, in particular to a preparation method of lithium iron phosphate.
  • iron phosphate As a chemical raw material, iron phosphate has a wide range of applications, and because of its unique electrochemical properties, it plays a huge role in the field of lithium-ion battery materials. In the field of battery materials, iron phosphate has become an ideal electrode material for electric vehicle batteries because it can be directly used as an intercalation electrode for lithium-ion batteries, has high thermal stability and good electrochemical cycle performance.
  • the traditional process uses ammonium dihydrogen phosphate, ferrous oxalate and lithium carbonate for physical mixing and high-temperature calcination to synthesize lithium iron phosphate. Irregular, gradually replaced by other methods.
  • ferric phosphate there are many synthetic techniques for ferric phosphate.
  • ferric sulfate or other soluble iron salts are generally used as the iron source, phosphoric acid or phosphate as the phosphorus source, and NaOH as the pH regulator, and the precipitation method is used to prepare ferric phosphate.
  • heating is generally required during the preparation process, and then lithium iron phosphate is synthesized at high temperature by adding lithium carbonate and the like to iron phosphate as a precursor.
  • Y. Huang used ferrous sulfate, phosphoric acid and hydrogen peroxide as raw materials to obtain ferric phosphate in a water bath at 80°C for 12 hours at a pH range of 1-2, and then used lithium hydroxide as a lithium source to prepare lithium iron phosphate materials with high rate performance. .
  • the process has very strict requirements on the control of the pH value. Generally, the pH value needs to be controlled between 1.6 and 2.0. When the pH value is too high, Fe(OH) 3 impurities may be precipitated, while the pH value is too low. Lead to incomplete precipitation of Fe 3+ .
  • the main purpose of the present invention is to provide a preparation method of lithium iron phosphate to solve the problem of low purity of lithium iron phosphate material in the prior art.
  • a preparation method of lithium iron phosphate comprising: step S1, mixing iron source, phosphorus source, and pH buffer to obtain a mixed solution; step S2, The mixed solution is subjected to a hydrothermal reaction to obtain an iron phosphate precursor; step S3, the iron phosphate precursor, lithium source, and carbon source are mixed and sintered to obtain lithium iron phosphate, wherein the pH buffer agent includes a carboxylate-containing compound.
  • the molar ratio of the above pH buffer agent to iron ions in the iron source is 0.005 ⁇ 0.05:1.
  • the above-mentioned pH buffering agent is selected from any one or more of monochloroacetic acid, ammonium acetate, and potassium hydrogen phthalate.
  • the pH value of the above mixed solution is 2.3-4.8.
  • step S1 includes: mixing the iron source and the phosphorus source to obtain a first solution; adding a surfactant and a pH buffer to the first solution to obtain a mixed solution.
  • the ratio of the mass of the surfactant to the volume of the first solution is 0.1 ⁇ 5 g:1L.
  • the surfactant is sodium dodecylbenzenesulfonate and/or sodium dodecylsulfate.
  • the pH value of the mixed solution is controlled to be 2.3-4.8.
  • the temperature of the above hydrothermal reaction is 50-90°C.
  • the time for the above hydrothermal reaction is 5-12 hours.
  • stirring speed is 1000-2000 r/min.
  • the molar ratio of the iron source to the iron phosphate precursor is 1 ⁇ 1.08:1.
  • the above iron source is selected from any one or more of ferric sulfate, ferric nitrate and ferric chloride.
  • the above-mentioned sintering process includes the first-stage sintering and the second-stage sintering in sequence, wherein the temperature of the first-stage sintering is 300-500°C.
  • first-stage sintering time is 3-6 hours.
  • the above-mentioned second-stage sintering temperature is 700-750°C.
  • the above-mentioned second-stage sintering time is 8-15 hours.
  • the iron phosphate precursor is dried before the first stage of sintering.
  • the molar ratio of the lithium source to the phosphorus source is 1.02 ⁇ 1.06:1.
  • the above-mentioned phosphorus source is selected from any one or more of phosphoric acid, ammonium dihydrogen phosphate, and sodium dihydrogen phosphate.
  • lithium source is lithium carbonate and/or lithium hydroxide.
  • the above-mentioned carbon source is 10-25wt% of the total amount of the iron phosphate precursor, lithium source and carbon source.
  • the above-mentioned carbon source is selected from any one or more of glucose, fructose, and maltose.
  • the pH buffering agent containing carboxylate can not only act as a complexing effect, but also have an extremely significant pH buffering effect, which is very important for controlling the stability of the entire reaction system.
  • the pH buffering agent can complex with the iron ions in the mixed solution, thereby greatly inhibiting the premature precipitation of iron ions in the form of iron hydroxide, thereby reducing the content of the iron hydroxide heterophase in the iron phosphate precursor.
  • pH buffering agent is used instead of strong alkaline substances such as sodium hydroxide to make the mixed solution reach a certain pH value, which avoids the generation of local ferric hydroxide heterophase caused by too strong alkalinity of NaOH or ammonia water, so that after sintering, it can obtain
  • strong alkaline substances such as sodium hydroxide
  • the carbon source is converted into reducing carbon, CO and other substances during the sintering process, so that the occurrence of oxidative side reactions during the sintering process can be suppressed as much as possible, and the carbon part is doped in the lithium iron phosphate And partially coated on the surface of lithium iron phosphate, thereby improving the conductivity of lithium iron phosphate, and then improving its conductivity.
  • using the lithium iron phosphate as a positive electrode material makes the battery have excellent conductivity and rate performance, etc. electrical properties.
  • the above-mentioned preparation process is simple, energy is saved, and reaction cost is reduced.
  • the present invention provides a method for preparing lithium iron phosphate.
  • a preparation method of lithium iron phosphate comprising: step S1, mixing iron source, phosphorus source, and pH buffer to obtain a mixed solution; step S2, The mixed solution is subjected to a hydrothermal reaction to obtain an iron phosphate precursor; step S3, the iron phosphate precursor, lithium source, and carbon source are mixed and sintered to obtain lithium iron phosphate, wherein the pH buffer agent includes a carboxylate-containing compound.
  • the pH buffer containing carboxylate can not only act as a complexing effect, but also have an extremely significant pH buffering effect, which is very important for controlling the stability of the entire reaction system.
  • the pH buffering agent can complex with the iron ions in the mixed liquid, thereby greatly inhibiting the premature precipitation of iron ions in the form of iron hydroxide, thereby reducing the content of the iron hydroxide heterophase in the iron phosphate precursor.
  • pH buffering agent is used instead of strong alkaline substances such as sodium hydroxide to make the mixed solution reach a certain pH value, which avoids the generation of local ferric hydroxide heterophase caused by too strong alkalinity of NaOH or ammonia water, so that after sintering, it can obtain
  • strong alkaline substances such as sodium hydroxide
  • the carbon source is converted into reducing carbon, CO and other substances during the sintering process, so that the occurrence of oxidative side reactions during the sintering process can be suppressed as much as possible, and the carbon part is doped in the lithium iron phosphate And partially coated on the surface of lithium iron phosphate, thereby improving the conductivity of lithium iron phosphate, and then improving its conductivity.
  • using the lithium iron phosphate as a positive electrode material makes the battery have excellent conductivity and rate performance, etc. electrical properties.
  • the above-mentioned preparation process is simple, energy is saved, and reaction cost is reduced.
  • the molar ratio of the above pH buffer agent to iron ions in the iron source is 0.005 ⁇ 0.05:1.
  • the above-mentioned pH buffering agent contains hydrophilic carboxylate, so it has better dispersibility in the water phase, which is more conducive to the coordination of its carboxylate and iron ions, and controls the pH buffering agent and iron in the iron source.
  • the molar ratio of ions in the above range is beneficial to reduce the precipitation of iron ions as much as possible, and helps to control the overall pH value of the mixed solution, thereby synergistically reducing the content of ferric hydroxide heterophase to a minimum.
  • the pH buffering agent of small molecular weight preferably is selected from monochloroacetic acid, ammonium acetate, ortho Any one or more of potassium hydrogen phthalate.
  • monochloroacetic acid preferably monochloroacetic acid, ammonium acetate, ortho Any one or more of potassium hydrogen phthalate.
  • the pH value of the above mixed solution is 2.3-4.8, which is conducive to improving the stability of iron ions in the mixed solution as much as possible and reducing the difficulty of pH adjustment during the co-precipitation reaction.
  • the above-mentioned mixed solution also includes a surfactant
  • step S1 includes: mixing the iron source and the phosphorus source to obtain a first solution; adding a surfactant and a pH buffer to the first solution agent to obtain a mixed solution, wherein, the ratio of the mass of the preferred surfactant to the volume of the first solution is 0.1 to 5 g: 1 L, and further, the preferred surfactant is sodium dodecylbenzenesulfonate and/or dodecylbenzenesulfonate Sodium Alkyl Sulfate.
  • surfactants help to control the particle size of subsequent lithium iron phosphate. In order to obtain lithium iron phosphate with uniform particle size as much as possible, the above-mentioned surfactants are preferred. Of course, those skilled in the art can also choose other surface active agents according to actual conditions. active agent, no more details here.
  • the pH value of the mixed solution in the above-mentioned hydrothermal reaction process is 2.3 to 4.8, and the temperature of the hydrothermal reaction is preferably 50 to 90°C, preferably water
  • the thermal reaction time is 5-12 hours, preferably stirring is carried out during the hydrothermal reaction, and the stirring speed is preferably 1000-2000 r/min. Stirring is beneficial to obtain lithium iron phosphate of uniform size.
  • the molar ratio of the above-mentioned iron source to the iron phosphate precursor is preferably 1-1.08:1, and the iron source is preferably selected from Any one or more of ferric sulfate, ferric nitrate and ferric chloride.
  • the formed lithium iron phosphate has stable and excellent performance.
  • the above-mentioned sintering process includes the first-stage sintering and the second-stage sintering in sequence, wherein the temperature of the first-stage sintering is 300-500°C, and the time for the first-stage sintering is preferably 3-6 hours; preferably the second-stage sintering The temperature is 700-750°C, and the time for the second stage of sintering is preferably 8-15 hours.
  • the first stage of sintering at a lower temperature can remove small molecules such as water, carbon dioxide, and carbon monoxide after the carbon source is decomposed, thereby reducing the impact of these small molecules on the second stage of sintering (at a higher temperature) as much as possible. Effect of crystallinity of lithium iron phosphate.
  • the molar ratio of the lithium source to the phosphorus source is 1.02-1.06:1
  • the phosphorus source is preferably selected from any one or more of phosphoric acid, ammonium dihydrogen phosphate, and sodium dihydrogen phosphate , preferably the lithium source is lithium carbonate and/or lithium hydroxide.
  • the above-mentioned ratio of lithium source and phosphorus source and their respective categories are more helpful to control the ratio of lithium to phosphorus in the composite and more stable lithium iron phosphate molecule.
  • the carbon source generates conductive carbon substances in the sintering process.
  • the above-mentioned carbon source is iron phosphate precursor, lithium source, and carbon source. 10-25% by weight, preferably the carbon source is selected from any one or more of glucose, fructose, and maltose.
  • 1.05:1 take by weighing 1.05 parts of ferric chloride and 1 part of phosphoric acid to be mixed with the first solution, the molar concentration of ferric chloride in this first solution is 5mol/L, then take by weighing monochloroacetic acid (one The volume ratio of chloroacetic acid quality to the first solution is 2g: 1L), ammonium acetate (the volume ratio of ammonium acetate quality to the first solution is 2g: 1L) and sodium dodecylbenzenesulfonate (dodecylbenzenesulfonate The volume ratio of sodium phthalate to the first solution is 0.5g: 1L) to add the first solution, take potassium hydrogen phthalate and add the first solution to make 0.04mol/L, and then use sodium hydroxide (0.5mol/L) and hydrochloric acid (0.5mol/L) to adjust the pH of the system at 3.5 to obtain a mixed solution.
  • monochloroacetic acid one
  • lithium hydroxide (the molar ratio of lithium hydroxide to phosphoric acid is 1.02:1) and glucose (20wt% of the total amount of iron phosphate precursor, lithium hydroxide, and glucose) to the iron phosphate precursor, and ball mill for 2 hours with ethanol as the dispersant , fully mixed, under the protection of nitrogen, the first stage of sintering was carried out at 350°C for 5 hours, and then the temperature was raised to 700°C to continue the second stage of sintering for 15 hours to obtain 1.029 parts of lithium iron phosphate.
  • the analysis shows that the ratio of iron to phosphorus in this material is 1.01:1.
  • 1.03:1 take by weighing 1.03 parts of ferric nitrate and 1 part of phosphoric acid to be mixed with the first solution, the molar concentration of iron trichloride in this first solution is 5mol/L, then take by weighing monochloroacetic acid (monochloroacetic acid).
  • monochloroacetic acid monochloroacetic acid
  • the volume ratio of mass to the first solution is 3g: 1L
  • ammonium acetate the volume ratio of ammonium acetate mass to the first solution is 4g: 1L
  • sodium dodecylbenzenesulfonate sodium dodecylbenzenesulfonate
  • the volume ratio with the first solution is 1g: 1L) to add the first solution, take potassium hydrogen phthalate and add the first solution to make 0.04mol/L, then use sodium hydroxide (0.5mol/L) and hydrochloric acid ( 0.5mol/L) to adjust the pH of the system at 2.8 to obtain a mixed solution.
  • 1.01:1 take by weighing 1.01 parts of ferric chloride and 1 part of phosphoric acid to be mixed with the first solution, the molar concentration of ferric chloride in this first solution is 5mol/L, then take by weighing monochloroacetic acid (one The volume ratio of chloroacetic acid quality to the first solution is 5g: 1L), ammonium acetate (the volume ratio of ammonium acetate quality to the first solution is 10g: 1L) and sodium dodecylbenzenesulfonate (dodecylbenzenesulfonate The volume ratio of sodium hydroxide to the first solution is 1.5g: 1L) was added to the first solution, and then the pH of the system was adjusted to 4.5 with sodium hydroxide (0.5mol/L) and hydrochloric acid (0.5mol/L) to obtain a mixed solution.
  • monochloroacetic acid one The volume ratio of chloroacetic acid quality to the first solution is 5g: 1L), ammonium acetate (the volume
  • the molar ratio of the total molar weight of monochloroacetic acid, ammonium acetate and potassium hydrogen phthalate to the iron ion in ferric chloride is 0.05:1, and finally 1.030 parts of lithium iron phosphate are obtained.
  • the molar ratio of the total molar weight of monochloroacetic acid, ammonium acetate and potassium hydrogen phthalate to the iron ion in ferric chloride is 0.005:1, and finally 1.0322 parts of lithium iron phosphate are obtained.
  • the molar ratio of the total molar weight of monochloroacetic acid, ammonium acetate and potassium hydrogen phthalate to the iron ion in ferric chloride is 0.004:1, and finally 1.0070 parts of lithium iron phosphate are obtained.
  • the molar ratio of the total molar weight of monochloroacetic acid, ammonium acetate and potassium hydrogen phthalate to the iron ion in ferric chloride is 0.08:1, and finally 1.0080 parts of lithium iron phosphate are obtained.
  • the pH value of the mixed liquid was 2.3, and the pH value of the mixed liquid was controlled to be 2.3 during the hydrothermal reaction process, and finally 1.0301 parts of lithium iron phosphate was obtained.
  • the pH value of the mixed liquid was 4.8, and the pH value of the mixed liquid was controlled to be 4.8 during the hydrothermal reaction process to finally obtain 1.0343 parts of lithium iron phosphate.
  • the pH value of the mixed liquid is 1.5, and the pH value of the mixed liquid is controlled to be 1.5 during the hydrothermal reaction process, and finally 1.0028 parts of lithium iron phosphate are obtained.
  • the lithium iron phosphate prepared in the above-mentioned Examples 1 to 13 and Comparative Example 1 were respectively prepared into positive electrodes, and lithium metal negative electrodes, 1mol/L LiPF 6 /EC+DMC+DEC (1:1:1) were used as the electrolyte Assemble into a button battery, test its discharge capacity and cycle capacity retention rate under the condition of 1C, and the test results are listed in Table 2.
  • the pH buffer containing carboxylate can not only act as a complexing effect, but also have an extremely significant pH buffering effect, which is very important for controlling the stability of the entire reaction system.
  • the pH buffering agent can complex with the iron ions in the mixed liquid, thereby greatly inhibiting the premature precipitation of iron ions in the form of iron hydroxide, thereby reducing the content of the iron hydroxide heterophase in the iron phosphate precursor.
  • pH buffering agent is used instead of strong alkaline substances such as sodium hydroxide to make the mixed solution reach a certain pH value, which avoids the generation of local ferric hydroxide heterophase caused by too strong alkalinity of NaOH or ammonia water, so that after sintering, it can obtain
  • strong alkaline substances such as sodium hydroxide
  • the carbon source is converted into reducing carbon, CO and other substances during the sintering process, so that the occurrence of oxidative side reactions during the sintering process can be suppressed as much as possible, and the carbon part is doped in the lithium iron phosphate And partially coated on the surface of lithium iron phosphate, thereby improving the conductivity of lithium iron phosphate, and then improving its conductivity.
  • using the lithium iron phosphate as a positive electrode material makes the battery have excellent conductivity and rate performance, etc. electrical properties.
  • the above-mentioned preparation process is simple, energy is saved, and reaction cost is reduced.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Composite Materials (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

本发明提供了一种磷酸铁锂的制备方法。该制备方法包括：步骤S1，将铁源、磷源、pH缓冲剂混合，得到混合液；步骤S2，将混合液进行水热反应，得到磷酸铁前体；步骤S3，将磷酸铁前体、锂源、碳源混合烧结，得到磷酸铁锂，其中，pH缓冲剂包括包含有羧酸根的化合物。含有羧酸根的pH缓冲剂既能够充当络合的作用，又有极其显著的pH缓冲作用，对于控制整个反应体系的稳定性至关重要，使最终的磷酸铁锂的物相单一化、产品性能稳定、流动性好、电导率高，进一步地，将该磷酸铁锂用作正极材料使得电池具有优良的电导率和倍率性等电学性能。且上述制备工艺简单、节约了能源、降低了反应成本。

Description

磷酸铁锂的制备方法
本申请是以CN申请号为202110517470.5，申请日为2021年05月12日的中国申请为基础，并主张其优先权，该CN申请的公开内容再次作为整体引入本申请中。
技术领域
本发明涉及磷酸铁锂的合成技术领域，具体而言，涉及一种磷酸铁锂的制备方法。
背景技术
磷酸铁作为一种化工原料，具有广泛的应用，因其独特的电化学性能，在锂离子电池材料领域发挥着巨大的作用。在电池材料领域，由于磷酸铁可以直接作为锂离子电池的嵌入电极，热稳定高，电化学循环性能好，因此已经成为电动汽车电池的理想电极材料。
目前，传统工艺采用磷酸二氢铵、草酸亚铁和碳酸锂进行物理混合和高温煅烧合成磷酸铁锂，虽然这些方法早期已经实现量产，但因产物粒径不易控制，分布不均匀，形貌不规则，逐渐被其它方法取代。
事实上，磷酸铁的合成工艺有多种，现代工业化生产一般采用硫酸铁或其他可溶性铁盐为铁源，以磷酸或者磷酸盐为磷源，以NaOH为pH调节剂，采用沉淀法制得磷酸铁，制备过程中一般需要加热，然后以磷酸铁为前驱体添加碳酸锂等进行磷酸铁锂高温合成。
Y.Huang以硫酸亚铁、磷酸以及双氧水为原料在pH为1～2的范围内80℃水浴保温12小时得到磷酸铁，再以氢氧化锂为锂源，制备出来高倍率性能的磷酸铁锂材料。但是实际生产中该工艺对pH值的控制要求很严格，一般需要将pH值控制在1.6～2.0之间，由于pH过高时则可能析出Fe(OH) 3杂质，而pH值过低则会导致Fe 3+沉淀不完全。而这样的pH的调节往往由于NaOH或氨水碱性过于强导致局部氢氧化铁杂相的产生，之后需要高温保持较长时间才能将其大部分去除，但仍然还会有少许残留，如此，既浪费能源，又影响磷酸铁锂的磷铁比从而降低其纯度和电化学性能。
发明内容
本发明的主要目的在于提供一种磷酸铁锂的制备方法，以解决现有技术中磷酸铁锂材料的纯度较低的问题。
为了实现上述目的，根据本发明的一个方面，提供了一种磷酸铁锂的制备方法，该制备方法包括：步骤S1，将铁源、磷源、pH缓冲剂混合，得到混合液；步骤S2，将混合液进行水热反应，得到磷酸铁前体；步骤S3，将磷酸铁前体、锂源、碳源混合烧结，得到磷酸铁锂，其中，pH缓冲剂包括包含有羧酸根的化合物。
进一步地，上述pH缓冲剂与铁源中铁离子的摩尔比为0.005～0.05:1。
进一步地，上述pH缓冲剂选自一氯乙酸、乙酸铵、邻苯二甲酸氢钾中的任意一种或多种。
进一步地，上述混合液的pH值为2.3～4.8。
进一步地，上述混合液中还包括表面活性剂，步骤S1包括：将铁源、磷源进行混合，得到第一溶液；在第一溶液中加入表面活性剂以及pH缓冲剂，得到混合液。
进一步地，上述表面活性剂的质量与第一溶液的体积之比为0.1～5g：1L。
进一步地，表面活性剂为十二烷基苯磺酸钠和/或十二烷基硫酸钠。
进一步地，上述水热反应过程中控制混合液的pH值为2.3～4.8。
进一步地，上述水热反应的温度为50～90℃。
进一步地，上述水热反应的时间为5～12h。
进一步地，在水热反应的过程中进行搅拌。
进一步地，上述搅拌的速度为1000～2000r/min。
进一步地，上述铁源与磷酸铁前体的摩尔比为1～1.08：1。
进一步地，上述铁源选自硫酸铁、硝酸铁和氯化铁中的任意一种或多种。
进一步地，上述烧结的过程包括依次进行的第一段烧结和第二段烧结，其中，第一段烧结的温度为300～500℃。
进一步地，上述第一段烧结的时间为3～6h。
进一步地，上述第二段烧结的温度为700～750℃。
进一步地，上述第二段烧结的时间为8～15h。
进一步地，在第一段烧结之前对磷酸铁前体进行干燥。
进一步地，上述锂源与磷源的摩尔比为1.02～1.06：1。
进一步地，上述磷源选自磷酸、磷酸二氢铵、磷酸二氢钠中的任意一种或多种。
进一步地，上述锂源为碳酸锂和/或氢氧化锂。
进一步地，上述碳源为磷酸铁前体、锂源、碳源总量的10～25wt％。
进一步地，上述碳源选自葡萄糖、果糖、麦芽糖中的任意一种或多种。
应用本发明的技术方案，含有羧酸根的pH缓冲剂既能够充当络合的作用，又有极其显著的pH缓冲作用，对于控制整个反应体系的稳定性至关重要。一方面pH缓冲剂能够与混合液 中的铁离子络合，从而极大程度地抑制铁离子以氢氧化铁的形式进行提前沉淀，进而降低磷酸铁前体中的氢氧化铁杂相的含量。另一方面采用pH缓冲剂代替氢氧化钠等强碱性物质来使混合液达到一定的pH值，避免了NaOH或氨水碱性过于强导致局部氢氧化铁杂相的产生，从而使烧结后得到的磷酸铁锂的物相单一化、产品性能稳定、流动性好、粒度分布窄，最终既提高了磷酸铁锂的纯度又提高了其产率。此外，碳源在烧结的过程中转换为具有还原性的碳、CO等物质，从而既可以尽可能地抑制烧结过程中氧化性副反应的发生，又使其中的碳部分掺杂于磷酸铁锂以及部分包覆于磷酸铁锂表面，从而提高了磷酸铁锂的电导率，进而提高了其导电性，进一步地，将该磷酸铁锂用作正极材料使得电池具有优良的电导率和倍率性等电学性能。且上述制备工艺简单、节约了能源、降低了反应成本。
具体实施方式
需要说明的是，在不冲突的情况下，本申请中的实施例及实施例中的特征可以相互组合。下面将结合实施例来详细说明本发明。
如背景技术所分析的，由于NaOH或氨水碱性过强导致局部氢氧化铁杂相的产生，之后需要高温保持较长时间才能将其大部分去除，但仍然还会有少许残留，从而导致现有技术中存在制备得到的磷酸铁锂的纯度较低的问题，为解决该问题，本发明提供了一种磷酸铁锂的制备方法。
在本申请的一种典型的实施方式中，提供了一种磷酸铁锂的制备方法，该制备方法包括：步骤S1，将铁源、磷源、pH缓冲剂混合，得到混合液；步骤S2，将混合液进行水热反应，得到磷酸铁前体；步骤S3，将磷酸铁前体、锂源、碳源混合烧结，得到磷酸铁锂，其中，pH缓冲剂包括包含有羧酸根的化合物。
含有羧酸根的pH缓冲剂既能够充当络合的作用，又有极其显著的pH缓冲作用，对于控制整个反应体系的稳定性至关重要。一方面pH缓冲剂能够与混合液中的铁离子络合，从而极大程度地抑制铁离子以氢氧化铁的形式进行提前沉淀，进而降低磷酸铁前体中的氢氧化铁杂相的含量。另一方面采用pH缓冲剂代替氢氧化钠等强碱性物质来使混合液达到一定的pH值，避免了NaOH或氨水碱性过于强导致局部氢氧化铁杂相的产生，从而使烧结后得到的磷酸铁锂的物相单一化、产品性能稳定、流动性好、粒度分布窄，最终既提高了磷酸铁锂的纯度又提高了其产率。此外，碳源在烧结的过程中转换为具有还原性的碳、CO等物质，从而既可以尽可能地抑制烧结过程中氧化性副反应的发生，又使其中的碳部分掺杂于磷酸铁锂以及部分包覆于磷酸铁锂表面，从而提高了磷酸铁锂的电导率，进而提高了其导电性，进一步地，将该磷酸铁锂用作正极材料使得电池具有优良的电导率和倍率性等电学性能。且上述制备工艺简单、节约了能源、降低了反应成本。
在本申请的一种实施例中，上述pH缓冲剂与铁源中铁离子的摩尔比为0.005～0.05:1。
上述pH缓冲剂含有亲水性的羧酸根，因此其在水相中具有较好的分散性，从而更有利于发挥其羧酸根与铁离子的配位作用，而且控制pH缓冲剂与铁源中铁离子的摩尔比在上述范围内有利于尽可能地降低铁离子的沉淀，又有助于控制混合液的整体pH值，从而协同性地将氢氧化铁杂相的含量降低到最小。
为尽可能地提高pH缓冲剂在水相中的分散性，从而提高整个反应体系的稳定性，优选小分子量的pH缓冲剂，进一步地优选上述pH缓冲剂选自一氯乙酸、乙酸铵、邻苯二甲酸氢钾中的任意一种或多种。当然，本领域技术人员也可以根据实际需要选择其它的pH缓冲剂，在此不再赘述。
在本申请的一些实施例中，上述混合液的pH值为2.3～4.8，从而有利于尽可能地提高混合液中铁离子的稳定性，并降低共沉淀反应过程中pH的调整难度。
在本申请的一种实施例中，上述混合液中还包括表面活性剂，步骤S1包括：将铁源、磷源进行混合，得到第一溶液；在第一溶液中加入表面活性剂以及pH缓冲剂，得到混合液，其中，优选表面活性剂的质量与第一溶液的体积之比为0.1～5g：1L，进一步地，优选表面活性剂为十二烷基苯磺酸钠和/或十二烷基硫酸钠。
表面活性剂有助于控制后续磷酸铁锂粒径的大小，为得到尽可能粒径均一的磷酸铁锂，优选上述的表面活性剂，当然，本领域技术人员也可以根据实际情况选用其它的表面活性剂，在此不再赘述。
为尽可能地提高上述水热反应的效率，缩短水热反应时间，优选上述水热反应过程中控制混合液的pH值为2.3～4.8，优选水热反应的温度为50～90℃，优选水热反应的时间为5～12h，优选在水热反应的过程中进行搅拌，优选搅拌的速度为1000～2000r/min。搅拌有利于得到大小均一的磷酸铁锂。
为使铁与磷等元素之间具有更合适的比例，从而协同得到组成更稳定的磷酸铁锂，优选上述铁源与磷酸铁前体的摩尔比为1～1.08：1，优选铁源选自硫酸铁、硝酸铁和氯化铁中的任意一种或多种。
为提高磷酸铁前体、锂源、碳源之间的相互协同作用，使形成的磷酸铁锂具有稳定的优良性能。优选上述烧结的过程包括依次进行的第一段烧结和第二段烧结，其中，第一段烧结的温度为300～500℃，优选第一段烧结的时间为3～6h；优选第二段烧结的温度为700～750℃，优选第二段烧结的时间为8～15h。其中，较低温度下的第一段烧结可以除去碳源分解之后的水、二氧化碳、一氧化碳等小分子物质，从而尽可能地降低这些小分子物质在第二段烧结时(较高温度下)对磷酸铁锂的结晶度的影响。为减小掺杂磷酸铁前体中的水分对烧结过程的影响，优选在第一段烧结之前对磷酸铁前体进行干燥，优选干燥的温度为200℃。
在本申请的一种实施例中，上述锂源与磷源的摩尔比为1.02～1.06：1，优选磷源选自磷酸、磷酸二氢铵、磷酸二氢钠中的任意一种或多种，优选锂源为碳酸锂和/或氢氧化锂。
上述的锂源与磷源的比例以及各自的类别更有助于控制得到复合更稳定磷酸铁锂分子中的锂磷比。
碳源在烧结过程中生成导电性碳物质，为进一步地提高碳源分解的效率，从而更充分地提高磷酸铁锂的导电性，优选上述碳源为磷酸铁前体、锂源、碳源总量的10～25wt％，优选碳源选自葡萄糖、果糖、麦芽糖中的任意一种或多种。
以下将结合具体实施例和对比例，对本申请的有益效果进行说明。
实施例1
按照1.05:1先称取1.05份的三氯化铁和1份的磷酸配制成第一溶液，该第一溶液中三氯化铁的摩尔浓度为5mol/L，然后称取一氯乙酸(一氯乙酸质量与第一溶液的体积比为2g：1L)、乙酸铵(乙酸铵质量与第一溶液的体积比为2g：1L)以及十二烷基苯磺酸钠(十二烷基苯磺酸钠与第一溶液的体积比为0.5g：1L)加入第一溶液，称取邻苯二甲酸氢钾加入第一溶液配成0.04mol/L，然后用氢氧化钠(0.5mol/L)和盐酸(0.5mol/L)调整体系的pH在3.5，得到混合液。
然后将混合液升温至70℃，控制转速1500r/min，持续控制温度70℃、控制水热反应过程中混合液的pH值为3.5，水热反应的时间为8小时，反应物料，离心脱水洗涤三次，控制湿料水分含量25～35％，然后以此湿料装钵180℃进行干燥48h，得到3.5微米圆片状前驱体，该圆片状厚度为100nm左右，得到磷酸铁前体，将磷酸铁前体加入氢氧化锂(氢氧化锂与磷酸的摩尔比为1.02:1)、葡萄糖(为磷酸铁前体、氢氧化锂、葡萄糖总量的20wt％)，以乙醇为分散剂球磨2h，充分混合，在氮气保护下350℃的温度进行第一段烧结5小时，随后升温至700℃继续第二段烧结15小时，得到1.029份的磷酸铁锂，分析可知该材料中的铁磷比为1.01:1。
实施例2
按照1.03:1先称取1.03份的硝酸铁和1份的磷酸配制成第一溶液，该第一溶液中三氯化铁的摩尔浓度为5mol/L，然后称取一氯乙酸(一氯乙酸质量与第一溶液的体积比为3g：1L)、乙酸铵(乙酸铵质量与第一溶液的体积比为4g：1L)以及十二烷基苯磺酸钠(十二烷基苯磺酸钠与第一溶液的体积比为1g：1L)加入第一溶液，称取邻苯二甲酸氢钾加入第一溶液配成0.04mol/L，然后用氢氧化钠(0.5mol/L)和盐酸(0.5mol/L)调整体系的pH在2.8，得到混合液。
然后将混合液升温至90℃，控制转速2000r/min，持续控制温度70℃、控制水热反应过程中混合液的pH值为2.8，水热反应的时间为6小时，反应物料，离心脱水洗涤三次，控制湿料水分含量25～35％，然后以此湿料装钵180℃进行干燥48h，得到2微米圆片状前驱体，该圆片状厚度为100nm左右，得到磷酸铁前体，将磷酸铁前体加入氢氧化锂(氢氧化锂与磷酸的摩尔比为1.03:1)、葡萄糖(为磷酸铁前体、氢氧化锂、葡萄糖总量的25wt％)，以乙醇为分散剂球磨2h，充分混合，在氮气保护下380℃的温度进行第一段烧结5小时，随后升温至750℃继续第二段烧结12小时，得到1.004份的磷酸铁锂，分析可知该材料中的铁磷比为0.995:1。
实施例3
按照1.01:1先称取1.01份的三氯化铁和1份的磷酸配制成第一溶液，该第一溶液中三氯化铁的摩尔浓度为5mol/L，然后称取一氯乙酸(一氯乙酸质量与第一溶液的体积比为5g：1L)、乙酸铵(乙酸铵质量与第一溶液的体积比为10g：1L)以及十二烷基苯磺酸钠(十二烷基苯磺酸钠与第一溶液的体积比为1.5g：1L)加入第一溶液，然后用氢氧化钠(0.5mol/L)和盐酸(0.5mol/L)调整体系的pH在4.5，得到混合液。
然后将混合液升温至50℃，控制转速1800r/min，持续控制温度50℃、控制水热反应过程中混合液的pH值为3.5，水热反应的时间为7小时，反应物料，离心脱水洗涤三次，控制湿料水分含量25～35％，然后以此湿料装钵180℃进行干燥48h，得到4微米圆片状前驱体，该圆片状厚度为150nm左右，得到磷酸铁前体，将磷酸铁前体加入氢氧化锂(氢氧化锂与磷酸的摩尔比为1.02:1)、葡萄糖(为磷酸铁前体、氢氧化锂、葡萄糖总量的15wt％)，以乙醇为分散剂球磨2h，充分混合，在氮气保护下400℃的温度进行第一段烧结3小时，随后升温至720℃继续第二段烧结12小时，得到0.9877份的磷酸铁锂，分析可知该材料中的铁磷比为0.99:1。
实施例4
实施例4与实施例1的区别在于，
一氯乙酸、乙酸铵以及邻苯二甲酸氢钾的总摩尔量与三氯化铁中铁离子的摩尔比为0.05:1，最终得到1.030份的磷酸铁锂。
实施例5
实施例5与实施例1的区别在于，
一氯乙酸、乙酸铵以及邻苯二甲酸氢钾的总摩尔量与三氯化铁中铁离子的摩尔比为0.005:1，最终得到1.0322份的磷酸铁锂。
实施例6
实施例6与实施例1的区别在于，
一氯乙酸、乙酸铵以及邻苯二甲酸氢钾的总摩尔量与三氯化铁中铁离子的摩尔比为0.004:1，最终得到1.0070份的磷酸铁锂。
实施例7
实施例7与实施例1的区别在于，
一氯乙酸、乙酸铵以及邻苯二甲酸氢钾的总摩尔量与三氯化铁中铁离子的摩尔比为0.08:1，最终得到1.0080份的磷酸铁锂。
实施例8
实施例8与实施例1的区别在于，
混合液的pH值为2.3，控制水热反应过程中混合液的pH值为2.3，最终得到1.0301份的磷酸铁锂。
实施例9
实施例9与实施例1的区别在于，
混合液的pH值为4.8，控制水热反应过程中混合液的pH值为4.8，最终得到1.0343份的磷酸铁锂。
实施例10
实施例10与实施例1的区别在于，
混合液的pH值为1.5，控制水热反应过程中混合液的pH值为1.5，最终得到1.0028份的磷酸铁锂。
实施例11
实施例11与实施例1的区别在于，
十二烷基苯磺酸钠(十二烷基苯磺酸钠与第一溶液的体积比为0.1g：1L，最终得到1.0301份的磷酸铁锂。
实施例12
实施例12与实施例1的区别在于，
十二烷基苯磺酸钠(十二烷基苯磺酸钠与第一溶液的体积比为5g：1L，最终得到1.0353份的磷酸铁锂。
实施例13
实施例13与实施例1的区别在于，
不加十二烷基苯磺酸钠，最终得到1.0038份的磷酸铁锂。
对比例1
对比例1与实施例1的区别在于，
采用氢氧化钠溶液代替一氯乙酸、乙酸铵以及邻苯二甲酸氢钾调整反应体系的在pH值为1.5的条件下进行反应，产出的产品中杂相占比较大，通过三次弱酸洗涤后铁磷比也只能达到1.03:1，容量低至132mAh/g。
分别测试上述实施例1至13、对比例1制备得到的磷酸铁锂的纯度和收率列于表1。
表1
实施/对比例 纯度/％ 收率/％
实施例1 99.4 98.0
实施例2 99.5 97.5
实施例3 99.2 97.8
实施例4 99.3 98.1
实施例5 99.4 98.3
实施例6 94.2 95.9
实施例7 94.3 96.0
实施例8 99.4 98.1
实施例9 98.2 98.5
实施例10 94.1 95.5
实施例11 99.4 98.1
实施例12 99.6 98.6
实施例13 94.4 95.6
对比例1 87.0 95.2
将上述实施例1至13、对比例1制备得到的磷酸铁锂分别制备成正极片，与锂金属负极、1mol/L的LiPF 6/EC+DMC+DEC(1:1:1)为电解液组装成扣式电池，在1C条件下测试其放电容量和循环容量保持率，并将测试结果列于表2。
表2
Figure PCTCN2022085377-appb-000001
Figure PCTCN2022085377-appb-000002
从以上的描述中，可以看出，本发明上述的实施例实现了如下技术效果：
含有羧酸根的pH缓冲剂既能够充当络合的作用，又有极其显著的pH缓冲作用，对于控制整个反应体系的稳定性至关重要。一方面pH缓冲剂能够与混合液中的铁离子络合，从而极大程度地抑制铁离子以氢氧化铁的形式进行提前沉淀，进而降低磷酸铁前体中的氢氧化铁杂相的含量。另一方面采用pH缓冲剂代替氢氧化钠等强碱性物质来使混合液达到一定的pH值，避免了NaOH或氨水碱性过于强导致局部氢氧化铁杂相的产生，从而使烧结后得到的磷酸铁锂的物相单一化、产品性能稳定、流动性好、粒度分布窄，最终既提高了磷酸铁锂的纯度又提高了其产率。此外，碳源在烧结的过程中转换为具有还原性的碳、CO等物质，从而既可以尽可能地抑制烧结过程中氧化性副反应的发生，又使其中的碳部分掺杂于磷酸铁锂以及部分包覆于磷酸铁锂表面，从而提高了磷酸铁锂的电导率，进而提高了其导电性，进一步地，将该磷酸铁锂用作正极材料使得电池具有优良的电导率和倍率性等电学性能。且上述制备工艺简单、节约了能源、降低了反应成本。
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (10)

  1. 一种磷酸铁锂的制备方法，其特征在于，所述制备方法包括：
    步骤S1，将铁源、磷源、pH缓冲剂混合，得到混合液；
    步骤S2，将所述混合液进行水热反应，得到磷酸铁前体；
    步骤S3，将所述磷酸铁前体、锂源、碳源混合烧结，得到所述磷酸铁锂，
    其中，所述pH缓冲剂包括包含有羧酸根的化合物。
  2. 根据权利要求1所述的制备方法，其特征在于，所述pH缓冲剂与所述铁源中铁离子的摩尔比为0.005～0.05:1。
  3. 根据权利要求1或2所述的制备方法，其特征在于，所述pH缓冲剂选自一氯乙酸、乙酸铵、邻苯二甲酸氢钾中的任意一种或多种。
  4. 根据权利要求1或2所述的制备方法，其特征在于，所述混合液的pH值为2.3～4.8。
  5. 根据权利要求1或2所述的制备方法，其特征在于，所述混合液中还包括表面活性剂，所述步骤S1包括：
    将铁源、磷源进行混合，得到第一溶液；
    在所述第一溶液中加入表面活性剂以及所述pH缓冲剂，得到所述混合液，
    其中，所述表面活性剂的质量与所述第一溶液的体积之比为0.1～5g：1L，所述表面活性剂为十二烷基苯磺酸钠和/或十二烷基硫酸钠。
  6. 根据权利要求1或2所述的制备方法，其特征在于，所述水热反应过程中控制所述混合液的pH值为2.3～4.8，所述水热反应的温度为50～90℃，所述水热反应的时间为5～12h。
  7. 根据权利要求1所述的制备方法，其特征在于，所述铁源与所述磷酸铁前体的摩尔比为1～1.08：1。
  8. 根据权利要求1所述的制备方法，其特征在于，所述烧结的过程包括依次进行的第一段烧结和第二段烧结，其中，所述第一段烧结的温度为300～500℃，所述第一段烧结的时间为3～6h；所述第二段烧结的温度为700～750℃，所述第二段烧结的时间为8～15h。
  9. 根据权利要求1所述的制备方法，其特征在于，所述锂源与所述磷源的摩尔比为1.02～1.06：1。
  10. 根据权利要求1所述的制备方法，其特征在于，所述碳源为所述磷酸铁前体、所述锂源、所述碳源总量的10～25wt％。
PCT/CN2022/085377 2021-05-12 2022-04-06 磷酸铁锂的制备方法 WO2022237393A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1020237043007A KR20240009446A (ko) 2021-05-12 2022-04-06 인산철리튬의 제조방법
EP22806363.2A EP4209456A1 (en) 2021-05-12 2022-04-06 Preparation method for lithium iron phosphate

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202110517470.5A CN112938927B (zh) 2021-05-12 2021-05-12 磷酸铁锂的制备方法
CN202110517470.5 2021-05-12

Publications (1)

Publication Number Publication Date
WO2022237393A1 true WO2022237393A1 (zh) 2022-11-17

Family

ID=76233742

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/085377 WO2022237393A1 (zh) 2021-05-12 2022-04-06 磷酸铁锂的制备方法

Country Status (4)

Country Link
EP (1) EP4209456A1 (zh)
KR (1) KR20240009446A (zh)
CN (1) CN112938927B (zh)
WO (1) WO2022237393A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115924873A (zh) * 2022-12-21 2023-04-07 中天新兴材料有限公司 球形纳米磷酸铁锂的制备方法
CN115959644A (zh) * 2022-12-30 2023-04-14 河南佰利新能源材料有限公司 一种分段烧结制备高性能磷酸铁锂的方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112938927B (zh) * 2021-05-12 2021-10-12 蜂巢能源科技有限公司 磷酸铁锂的制备方法
CN115676793A (zh) * 2022-09-30 2023-02-03 山东精工电子科技股份有限公司 叶状磷酸铁锂材料的制备方法及其叶状磷酸铁锂材料

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102881902A (zh) * 2012-10-22 2013-01-16 山东海特电子新材料有限公司 工业化生产磷酸铁锂正极材料的方法
CN103079998A (zh) * 2010-08-18 2013-05-01 株式会社村田制作所 磷酸铁的制造方法、磷酸铁锂、电极活性物质及二次电池
KR20140021791A (ko) * 2012-08-10 2014-02-20 한국교통대학교산학협력단 pH 조절을 이용한 FePO₄제조 방법 및 이를 이용한 리튬이차전지 양극용 LiFePO₄/C 복합재 제조 방법
CN107324306A (zh) * 2017-07-18 2017-11-07 江西悦安超细金属有限公司 一种纳米磷酸铁锂及其制备方法
CN108539132A (zh) * 2018-01-26 2018-09-14 澳洋集团有限公司 一种氧化锌复合磷酸铁锂正极材料的制备方法
CN111422851A (zh) * 2020-03-02 2020-07-17 曲靖市德方纳米科技有限公司 磷酸铁锂及其制备方法
CN112938927A (zh) * 2021-05-12 2021-06-11 蜂巢能源科技有限公司 磷酸铁锂的制备方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106207091A (zh) * 2016-08-10 2016-12-07 南京大学 一种锂离子电池柔性正极、其制备方法及超柔性锂离子全电池
CN106384822A (zh) * 2016-12-06 2017-02-08 中钢集团安徽天源科技股份有限公司 无定型态电池级磷酸铁的制备方法、磷酸铁锂、电池正极材料及二次电池

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103079998A (zh) * 2010-08-18 2013-05-01 株式会社村田制作所 磷酸铁的制造方法、磷酸铁锂、电极活性物质及二次电池
KR20140021791A (ko) * 2012-08-10 2014-02-20 한국교통대학교산학협력단 pH 조절을 이용한 FePO₄제조 방법 및 이를 이용한 리튬이차전지 양극용 LiFePO₄/C 복합재 제조 방법
CN102881902A (zh) * 2012-10-22 2013-01-16 山东海特电子新材料有限公司 工业化生产磷酸铁锂正极材料的方法
CN107324306A (zh) * 2017-07-18 2017-11-07 江西悦安超细金属有限公司 一种纳米磷酸铁锂及其制备方法
CN108539132A (zh) * 2018-01-26 2018-09-14 澳洋集团有限公司 一种氧化锌复合磷酸铁锂正极材料的制备方法
CN111422851A (zh) * 2020-03-02 2020-07-17 曲靖市德方纳米科技有限公司 磷酸铁锂及其制备方法
CN112938927A (zh) * 2021-05-12 2021-06-11 蜂巢能源科技有限公司 磷酸铁锂的制备方法

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115924873A (zh) * 2022-12-21 2023-04-07 中天新兴材料有限公司 球形纳米磷酸铁锂的制备方法
CN115959644A (zh) * 2022-12-30 2023-04-14 河南佰利新能源材料有限公司 一种分段烧结制备高性能磷酸铁锂的方法

Also Published As

Publication number Publication date
CN112938927A (zh) 2021-06-11
EP4209456A1 (en) 2023-07-12
CN112938927B (zh) 2021-10-12
KR20240009446A (ko) 2024-01-22

Similar Documents

Publication Publication Date Title
WO2021168600A1 (zh) 一种低水分含量的普鲁士蓝钠离子电池正极材料及其制备方法和钠离子电池
CN110048118B (zh) 一种高镍型镍钴锰酸锂单晶前驱体及其制备方法和高镍型镍钴锰酸锂单晶正极材料
US10957903B2 (en) Layered lithium-rich manganese-based cathode material with olivine structured LIMPO4 surface modification and preparation method thereof
WO2022237393A1 (zh) 磷酸铁锂的制备方法
JP2018504363A (ja) アルミニウム元素勾配分布を有するニッケルコバルトアルミニウム前駆体材料及び正極材料を製造する方法
CN102593427B (zh) 一种液相制备覆碳球形纳米磷酸铁锂的方法
WO2021120040A1 (zh) 一种高密度铝掺杂氧化钴的制备方法
CN108288703B (zh) 一种石墨烯包覆掺氟钛酸锂纳米线的制备方法及其应用
CN111082059A (zh) 一种v掺杂p2型钠离子电池正极材料及其制备方法
CN111916701B (zh) 一种包覆型正极材料及其制备方法和用途
CN108598405B (zh) 一种三维石墨烯氧化锡碳复合负极材料的制备方法
CN109616658B (zh) 一种硒、硫酸根共掺杂高镍正极材料及其制备方法和应用
CN109638275B (zh) 一种硒、硅酸根共掺杂高镍正极材料及其制备方法和应用
CN112777611B (zh) 一种菱形相普鲁士蓝衍生物及其制备方法和应用
CN114242973A (zh) 富锰的钠离子正极材料及其制备方法和应用
CN111370689B (zh) 一种钌、铝共掺杂钴酸锂正极材料及其制备方法
CN117476858A (zh) 一种改性硫酸铁钠正极材料及其制备方法和应用
CN108461730B (zh) 一种锂离子电池正极材料及其制备方法
CN114933292B (zh) 一种磷酸铁锂的制备方法及其应用
CN108417824B (zh) 一种高性能锂电池负极材料碳包覆钛酸锂的制备方法
CN108023079B (zh) 一种混合过渡金属硼酸盐负极材料及其制备方法
CN113764671A (zh) 一种锂离子电池正极材料
WO2024082539A1 (zh) 一种磷酸锰铁锂正极材料及其制备方法和应用
CN114436234B (zh) 一种使用FePO4/C复合材料制备的磷酸铁锂材料及其制备方法
CN117374262B (zh) 内源异质结阳极材料及其制备方法、负极和锂离子电池

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22806363

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2022806363

Country of ref document: EP

Effective date: 20230403

ENP Entry into the national phase

Ref document number: 20237043007

Country of ref document: KR

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1020237043007

Country of ref document: KR

NENP Non-entry into the national phase

Ref country code: DE