WO2025035278A1 - 一种磷酸铁锂正极材料除pvdf除铝的方法 - Google Patents

一种磷酸铁锂正极材料除pvdf除铝的方法 Download PDF

Info

Publication number
WO2025035278A1
WO2025035278A1 PCT/CN2023/112596 CN2023112596W WO2025035278A1 WO 2025035278 A1 WO2025035278 A1 WO 2025035278A1 CN 2023112596 W CN2023112596 W CN 2023112596W WO 2025035278 A1 WO2025035278 A1 WO 2025035278A1
Authority
WO
WIPO (PCT)
Prior art keywords
iron phosphate
lithium iron
aluminum
pvdf
positive electrode
Prior art date
Legal status (The legal status 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 status listed.)
Pending
Application number
PCT/CN2023/112596
Other languages
English (en)
French (fr)
Inventor
龙芬
李长东
阮丁山
周游
李强
宁培超
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hunan Brunp Recycling Technology Co Ltd
Guangdong Brunp Recycling Technology Co Ltd
Original Assignee
Hunan Brunp Recycling Technology Co Ltd
Guangdong Brunp Recycling Technology Co Ltd
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 Hunan Brunp Recycling Technology Co Ltd, Guangdong Brunp Recycling Technology Co Ltd filed Critical Hunan Brunp Recycling Technology Co Ltd
Priority to PCT/CN2023/112596 priority Critical patent/WO2025035278A1/zh
Priority to CN202380011476.2A priority patent/CN117295685B/zh
Publication of WO2025035278A1 publication Critical patent/WO2025035278A1/zh
Anticipated expiration legal-status Critical
Pending legal-status Critical Current

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
    • 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
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/54—Reclaiming serviceable parts of waste accumulators
    • 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
    • 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
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies
    • Y02W30/84—Recycling of batteries or fuel cells

Definitions

  • the present invention belongs to the technical field of lithium-ion batteries, and in particular relates to a method for removing PVDF and aluminum from a lithium iron phosphate positive electrode material.
  • Lithium-ion batteries are widely used in pure/hybrid electric vehicles and various electronic devices due to their advantages such as high operating voltage, long cycle life, and no memory effect.
  • lithium iron phosphate batteries as a simple and safe power source, have high cycle performance and do not contain precious metals. They occupy a large market share in power batteries, and their demand in the fields of new energy, base station energy storage, etc. is growing explosively.
  • the service life of lithium-ion batteries is generally 5 to 7 years, and a large number of waste lithium iron phosphate batteries will be generated in the next few years.
  • waste batteries contain a large number of valuable components, such as iron, copper, aluminum, lithium and phosphorus. Recycling these valuable components can avoid wasting these resources.
  • the organic electrolyte in the battery will cause serious pollution to water quality and soil. Therefore, the recycling of waste LFP batteries is imperative.
  • LFP batteries The recycling methods of LFP batteries are generally divided into three categories, namely direct regeneration, pyrometallurgy and hydrometallurgy.
  • direct regeneration has the advantage of a short and efficient recycling process.
  • direct regeneration can be used to recover the remaining waste, but it has difficulties in handling materials with high impurity content, materials from different sources or different types.
  • the present disclosure aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present disclosure proposes a method for removing PVDF and aluminum from a lithium iron phosphate positive electrode material.
  • a method for removing PVDF and aluminum from a lithium iron phosphate positive electrode material comprising the following steps:
  • step S2 mixing alcohol, a second ionic liquid and the lithium iron phosphate powder except PVDF obtained in step S1, heating to separate alcohol and aluminum alkoxide, and obtaining lithium iron phosphate powder except PVDF and aluminum;
  • the first ionic liquid and the second ionic liquid are independently selected from fluorine-containing ionic liquids.
  • the lithium iron phosphate powder is obtained by discharging, disassembling and crushing waste lithium iron phosphate batteries.
  • the ionic liquid is at least one of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (CAS: 174899-82-2), 1-ethyl-3-methylimidazolium tetrafluoroborate (CAS: 143314-16-3), 1-ethyl-3-methylimidazolium hexafluorophosphate (CAS: 155371-19-0), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (CAS: 235789-75-0), 1-ethyl-3-methylimidazolium trifluoroacetate (CAS: 174899-65-1) or 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (CAS: 145022-44-2).
  • the mass of the ionic liquid is 5-20% of the mass of the lithium iron phosphate powder.
  • step S1 the liquid-to-solid ratio of the ethanol to the lithium iron phosphate powder is 2 to 5 mL/g.
  • step S1 the process parameters of the ball milling are: ball-to-material ratio is (4-10):1; the rotation speed is 300-400 rpm; and the time is 120-480 min.
  • the solid-liquid separation includes: washing the ball-milled mixture, separating the washed liquid, and obtaining lithium iron phosphate powder without PVDF, wherein the washing liquid can be the same as the alcohol added during ball milling.
  • step S1 the lithium iron phosphate powder except for PVDF is further dried; the drying temperature is 50 to 80° C., and the drying time is 4 to 24 hours.
  • step S1 the liquid phase after solid-liquid separation is subjected to rotary evaporation, and the solid-liquid separation is performed again to obtain
  • the ethanol can be recovered by rotary evaporation of the filtrate obtained by washing the lithium iron phosphate mixture with ethanol and separating the solid and liquid.
  • the temperature of the rotary evaporation is 50-80° C. and the vacuum degree is about -0.1 MPa.
  • the alcohol is at least one of n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol or tert-butanol.
  • step S2 the liquid-to-solid ratio of the alcohol to the lithium iron phosphate mixture is 5-10 mL/g.
  • the mass of the second ionic liquid is 5-20% of the mass of the lithium iron phosphate mixture.
  • the heating separation of alcohol and aluminum alkoxide includes: first heating to generate aluminum alkoxide, and then heating again to separate alcohol and aluminum alkoxide in sequence. Under heating conditions, the ionic liquid acts as a catalyst to react aluminum and alcohol to convert into aluminum alkoxide.
  • the temperature of the first heating is 80-120°C; the time of the first heating is 60-180 minutes; the temperature of the second heating is 80-180°C; the time of the second heating is 60-120 minutes.
  • the aluminum alkoxide can be evaporated by the second heating to remove aluminum impurities in the lithium iron phosphate.
  • a method for recycling lithium-ion batteries comprising the steps of the method for removing PVDF and aluminum from lithium iron phosphate positive electrode materials described in the first aspect of the present disclosure.
  • the application of the method for removing PVDF and aluminum from the lithium iron phosphate positive electrode material described in the first aspect of the present disclosure in the recycling of lithium ion batteries is proposed.
  • the present invention separates PVDF from lithium iron phosphate powder by adding fluorine-containing ionic liquid to lithium iron phosphate material to react with PVDF at a certain temperature to form hydrogen bonds; at the same time, the fluorine-containing ionic liquid can also be used as a catalyst to catalyze the reaction between aluminum and alcohol, so that aluminum impurities are converted into aluminum alkoxides and removed from lithium iron phosphate.
  • the method is simple to operate, and PVDF and aluminum impurities are removed from lithium iron phosphate positive electrode materials in two steps.
  • the structure of lithium iron phosphate can be ensured not to be destroyed and impurities will not be introduced during the process of removing PVDF and aluminum.
  • the present invention separates PVDF from the lithium iron phosphate positive electrode material by forming hydrogen bonds between the ionic liquid and PVDF, and the hydrogen bonds are easily broken under heating conditions, so that the ionic liquid and PVDF can be recovered and reused.
  • the present invention forms hydrogen bonds between ionic liquids and alcohols, thereby effectively catalyzing the reaction between aluminum and alcohols, so that aluminum impurities are converted into aluminum alkoxides for removal, and the alcohol used can also be recycled, thus forming an economical, green and environmentally friendly closed-loop recycling route.
  • FIG1 is a flow chart of removing PVDF and aluminum impurities from lithium iron phosphate positive electrode materials and regenerating lithium iron phosphate in Example 1 of the present disclosure.
  • a method for removing PVDF and aluminum from a lithium iron phosphate cathode material comprises the following steps:
  • step 3 The filter residue obtained in step 3 is placed in an oven and dried at 50° C. for 24 h to obtain lithium iron phosphate powder regenerated from PVDF.
  • step 3 The filtrate obtained in step 3 is subjected to rotary evaporation at 50° C. to recover ethanol at a vacuum degree of ⁇ 0.1 MPa to obtain a mixture of 1-ethyl-3-methylimidazole bistrifluoromethylsulfonyl imide and PVDF.
  • step 5 The mixture obtained in step 5 is filtered to recover 1-ethyl-3-methylimidazole bis(trifluoromethylsulfonyl)imide and PVDF.
  • step 8 The mixture obtained in step 8 is filtered to obtain purified lithium iron phosphate powder and 1-ethyl-3-methylimidazole bis(trifluoromethylsulfonyl)imide is recovered.
  • a method for recycling lithium-ion batteries comprises the steps of the above-mentioned method for removing PVDF and aluminum from lithium iron phosphate positive electrode materials.
  • a method for removing PVDF and aluminum from a lithium iron phosphate positive electrode material comprises the following steps:
  • step 3 The filter residue obtained in step 3 is placed in an oven and dried at 60° C. for 12 h to obtain lithium iron phosphate powder regenerated from PVDF.
  • step 3 The filtrate obtained in step 3 is subjected to rotary evaporation at 70° C. with a vacuum degree of ⁇ 0.1 MPa, and ethanol is recovered to obtain a mixture of 1-ethyl-3-methylimidazolium tetrafluoroborate and PVDF.
  • step 5 The mixture obtained in step 5 is filtered to recover 1-ethyl-3-methylimidazolium tetrafluoroborate and PVDF.
  • step 8 The mixture obtained in step 8 is filtered to obtain purified lithium iron phosphate powder and 1-ethyl-3-methylimidazolium tetrafluoroborate is recovered.
  • a method for recycling lithium-ion batteries comprises the steps of the above-mentioned method for removing PVDF and aluminum from lithium iron phosphate positive electrode materials.
  • a method for removing PVDF and aluminum from a lithium iron phosphate positive electrode material comprises the following steps:
  • step 3 The filter residue obtained in step 3 is placed in an oven and dried at 80° C. for 4 h to obtain lithium iron phosphate powder regenerated from PVDF.
  • step 3 The filtrate obtained in step 3 is subjected to rotary evaporation at 80° C. and a vacuum degree of ⁇ 0.1 MPa to recover ethanol, thereby obtaining a mixture of 1-ethyl-3-methylimidazole hexafluorophosphate and PVDF.
  • step 5 The mixture obtained in step 5 is filtered to recover 1-ethyl-3-methylimidazolium hexafluorophosphate and PVDF.
  • step 8 The mixture obtained in step 8 is filtered to obtain purified lithium iron phosphate powder and 1-ethyl-3-methylimidazolium hexafluorophosphate is recovered.
  • a method for recycling lithium-ion batteries comprises the steps of the above-mentioned method for removing PVDF and aluminum from lithium iron phosphate positive electrode materials.
  • step 2 1-ethyl-3-methylimidazole bis(trifluoromethylsulfonyl)imide in an amount of 2 wt % of lithium iron phosphate powder is added.
  • step 7 the liquid-to-solid ratio of isopropanol to lithium iron phosphate powder except PVDF is 3 mL/g.
  • Example 1 The only difference from Example 1 is that the ionic liquid in step 2 and step 7 is replaced by 1-ethyl-3-methylimidazolium chloride.
  • Table 1 is a test data table of Fe, Li and Al contents (specific data are obtained by ICP-AES test), P content (specific data are obtained by titration) and F content (specific data are obtained by potentiometric test) of waste lithium iron phosphate materials, lithium iron phosphate products prepared in Examples 1, 2, 3 and Comparative Examples 1, 2, 3.
  • the Fe, P and Li contents in the lithium iron phosphate prepared in the examples are normal, and the F content and Al content are effectively reduced, which meets the industrial production standards for lithium iron phosphate lithium batteries.
  • the Al content in the lithium iron phosphate prepared in Example 1 is reduced from 2.1% to 0.04%, and the F content is reduced from 0.2% to 0.002%.
  • Comparative Example 1 relative to Example 1, less 1-ethyl-3-methylimidazole bistrifluoromethylsulfonyl imide was added in step 2, and more PVDF remained in the prepared lithium iron phosphate powder, with an F content of 0.12%; in Comparative Example 2, relative to Example 1, less isopropanol was added in step 7, and more Al remained in the prepared lithium iron phosphate powder, with an Al content of 1.3%; in Comparative Example 3, relative to Example 1, a fluorine-free ionic liquid was used, and the F and Al contents in the prepared lithium iron phosphate powder were substantially not reduced, with an F content of 0.2% and an Al content of 2.08%.
  • Table 2 shows the electrochemical performance of lithium iron phosphate batteries prepared from Examples 1, 2, and 3 and raw materials, and the specific data are obtained by testing with equipment such as an electrochemical workstation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Secondary Cells (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

本公开提出了一种磷酸铁锂正极材料除PVDF除铝的方法，包括以下步骤：S1：将磷酸铁锂粉、第一离子液体及乙醇进行混合球磨，固液分离，得到除PVDF的磷酸铁锂粉；S2：将醇、第二离子液体及步骤S1制得的所述除PVDF的磷酸铁锂粉进行混合加热，分离醇和铝醇盐，得到除PVDF除铝的磷酸铁锂粉；其中，步骤S1、S2中所述第一离子液体、第二离子液体独立选自含氟离子液体。

Description

一种磷酸铁锂正极材料除PVDF除铝的方法 技术领域
本公开属于锂离子电池技术领域，具体涉及一种磷酸铁锂正极材料除PVDF除铝的方法。
背景技术
锂离子电池因具有工作电压高、循环寿命长、无记忆效应等优点，广泛应用于纯/混合电动汽车和各种电子设备。其中磷酸铁锂电池作为简单安全的电源，具有高循环性能，不含贵金属，在动力电池中占有较大的市场份额，在新能源、基站储能等领域的需求量呈爆发式增长。但是锂离子电池的使用寿命一般为5～7年，在未来几年将产生大量的废旧磷酸铁锂电池。一方面废旧电池中含有大量有价值的成分，如铁、铜、铝、锂和磷，回收这些有价值的成分可以避免浪费这些资源。另一方面电池中的有机物电解液会对水质和土壤造成严重污染。因此，废旧LFP电池的回收势在必行。
LFP电池的回收方法一般分为三类，即直接再生、火法冶金和湿法冶金。直接再生法相比火法冶金和湿法冶金来说，具有回收流程简短高效的优点。作为一个短而高效的过程，直接再生可以用来恢复剩余的废料，但它在处理杂质含量高的材料、来源不同或种类不同的材料时存在困难。
要把废旧磷酸铁锂正极材料中的PVDF除掉一般依靠高温裂解PVDF转换成氟化氢和氟碳有机物除去。但是在该过程中，生成的氟化氢会侵蚀磷酸铁锂材料生成氟化锂，致使材料性能下降，且氟化锂作为杂质极难去除；另一方面，一般常用碱液除掉废旧磷酸铁锂正极材料中的铝杂质，该方法不可避免会引入钠杂质，同时对磷酸铁锂材料也有一定程度的损坏。因此，在如何高效除去废旧磷酸铁锂材料中的PVDF和铝杂质而又能保证磷酸铁锂结构完整性这一问题上有较大挑战。
发明内容
本公开旨在至少解决上述现有技术中存在的技术问题之一。为此，本公开提出一种磷酸铁锂正极材料除PVDF除铝的方法。
根据本公开的第一方面，提出了一种磷酸铁锂正极材料除PVDF除铝的方法，包括以下步骤：
S1：将磷酸铁锂粉、第一离子液体及乙醇进行混合球磨，固液分离，得到除PVDF的磷酸铁锂粉；
S2：将醇、第二离子液体及步骤S1制得的所述除PVDF的磷酸铁锂粉进行混合，加热分离醇和铝醇盐，得到除PVDF除铝的磷酸铁锂粉；
其中，步骤S1、S2中所述第一离子液体、第二离子液体独立选自含氟离子液体。
在一些实施方式中，步骤S1中，所述磷酸铁锂粉由废旧磷酸铁锂电池进行放电、拆解及破碎处理后获得。
在一些实施方式中，步骤S1、S2中，所述离子液体为1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺(CAS:174899-82-2)、1-乙基-3-甲基咪唑四氟硼酸盐(CAS:143314-16-3)、1-乙基-3-甲基咪唑六氟磷酸盐(CAS:155371-19-0)、1-乙基-3-甲基咪唑双(氟磺酰)亚胺盐(CAS:235789-75-0)、1-乙基-3-甲基咪唑三氟乙酸盐(CAS:174899-65-1)或1-乙基-3-甲基咪唑三氟甲磺酸盐(CAS:145022-44-2)中的至少一种。
在一些实施方式中，步骤S1中，所述离子液体的质量为所述磷酸铁锂粉质量的5～20％。
在一些实施方式中，步骤S1中，所述乙醇与所述磷酸铁锂粉的液固比为2～5mL/g。
在一些实施方式中，步骤S1中，所述球磨的工艺参数为：球料比为(4～10)：1；转速为300～400rpm；时间为120～480min。
在一些实施方式中，步骤S1中，所述固液分离包括：将球磨后的混合物进行洗涤，分离洗涤后液，得到除PVDF的磷酸铁锂粉。其中，洗涤液可以与球磨时加入的醇相同。
在一些实施方式中，步骤S1中，还对所述除PVDF的磷酸铁锂粉进行烘干；所述烘干的温度为50～80℃，时间为4～24h。
在一些实施方式中，步骤S1中，固液分离后的液相进行旋蒸，再次固液分离后得 到离子液体和PVDF。将乙醇洗涤磷酸铁锂混合物后固液分离所得的滤液进行旋蒸可回收乙醇。
在一些实施方式中，所述旋蒸的温度为50～80℃；真空度约为-0.1MPa。
在一些实施方式中，步骤S2中，所述醇为正丙醇、异丙醇、正丁醇、异丁醇、仲丁醇或叔丁醇中的至少一种。
在一些实施方式中，步骤S2中，所述醇与所述磷酸铁锂混合物的液固比为5～10mL/g。
在一些实施方式中，步骤S2中，所述第二离子液体的质量为所述磷酸铁锂混合物质量的5～20％。
在一些实施方式中，步骤S2中，所述加热分离醇和铝醇盐包括：先进行一次加热，生成铝醇盐，再进行二次加热，依次分离醇和铝醇盐。在加热的条件下，离子液体作为催化剂使铝和醇反应转化为铝醇盐。
在一些实施方式中，步骤S2中，所述一次加热的温度为80～120℃；所述一次加热的时间为60～180min；所述二次加热的温度为80～180℃；所述二次加热的时间为60～120min。通过二次加热可将铝醇盐蒸出从而除去磷酸铁锂中的铝杂质。
根据本公开的第二方面，提出了一种锂离子电池回收的方法，包括本公开第一方面所述的磷酸铁锂正极材料除PVDF除铝的方法的步骤。
根据本公开的第三方面，提出了本公开第一方面所述的磷酸铁锂正极材料除PVDF除铝的方法在锂离子电池回收中的应用。
根据本公开的一种实施方式，至少具有以下有益效果：
(1)本公开通过在磷酸铁锂材料中加入含氟离子液体与PVDF在一定温度下反应形成氢键从而使PVDF从磷酸铁锂粉中脱离出来；同时该含氟离子液体又可作为催化剂催化铝和醇反应，使铝杂质转化为铝醇盐从磷酸铁锂中除去。该方法操作简单，两步将PVDF和铝杂质从磷酸铁锂正极材料中去除，而且在除PVDF和铝过程中可以保证磷酸铁锂的结构不被破坏且不会引入杂质。
(2)本公开通过离子液体与PVDF形成氢键而使PVDF从磷酸铁锂正极材料中脱离，而该氢键容易在加热的条件下断裂可使离子液体和PVDF回收再利用。
(3)本公开通过离子液体与醇形成氢键进而有效催化了铝和醇的反应，使铝杂质转化为铝醇盐除去，而且所用醇也可回收，可以形成一条经济绿色环保的闭环回收路线。
(4)由于本公开除PVDF和铝杂质再生磷酸铁锂流程简单且易于操作，可大规模应用于工业。
附图说明
下面结合附图和实施例对本公开做进一步的说明，其中：
图1为本公开实施例1磷酸铁锂正极材料除PVDF和铝杂质再生磷酸铁锂的流程图。
具体实施方式
以下将结合实施例对本公开的构思及产生的技术效果进行清楚、完整地描述，以充分地理解本公开的目的、特征和效果。
实施例1
一种磷酸铁锂正极材料除PVDF除铝的方法，如图1所示，包括以下步骤：
(1)将废旧磷酸铁锂电池进行放电、拆解和破碎处理得到废旧磷酸铁锂正极材料。
(2)将步骤1得到的磷酸铁锂粉，质量为磷酸铁锂粉5wt％的1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺，乙醇(液固比＝2mL/g)装入球磨罐中,向球磨罐内加入球料比为4:1的锆球，置于行星球磨机上以400rpm球磨120min得到磷酸铁锂混合物。
(3)将步骤2得到的磷酸铁锂混合物用质量比为磷酸铁锂5倍的乙醇洗涤再抽滤，重复3次。
(4)将步骤3得到的滤渣放入烘箱中50℃烘24h得到除PVDF再生的磷酸铁锂粉。
(5)将步骤3得到的滤液50℃旋蒸回收乙醇，真空度为-0.1MPa，得到1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺和PVDF的混合物。
(6)将步骤5得到的混合物抽滤，回收1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺和PVDF。
(7)将步骤4得到的除PVDF的磷酸铁锂粉，异丙醇(液固比＝5mL/g)，质量为磷酸铁锂粉5wt％的1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺作催化剂加入烧瓶于油浴锅中85℃加热回流1h，使铝尽可能完全转化为异丙醇铝。
(8)待铝转化为异丙醇铝后，继续90℃加热30min，使异丙醇溶剂蒸出并回收，将温度升高至140℃加热50min，蒸出异丙醇铝得到除PVDF除铝的磷酸铁锂粉和离子液体混合物。
(9)将步骤8得到的混合物抽滤，得到纯化后的磷酸铁锂粉并回收1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺。
一种锂离子电池回收的方法，包括上述磷酸铁锂正极材料除PVDF除铝的方法的步骤。
实施例2
一种磷酸铁锂正极材料除PVDF除铝的方法，包括以下步骤：
(1)将废旧磷酸铁锂电池进行放电、拆解和破碎处理得到废旧磷酸铁锂正极材料。
(2)将步骤1得到的磷酸铁锂粉，质量为磷酸铁锂粉10wt％的1-乙基-3-甲基咪唑四氟硼酸盐，乙醇(液固比＝4mL/g)装入球磨罐中,向球磨罐内加入球料比为6:1的锆球，置于行星球磨机上以400rpm球磨240min得到磷酸铁锂混合物。
(3)将步骤2得到的磷酸铁锂混合物用质量比为磷酸铁锂5倍的乙醇洗涤再抽滤，重复3次。
(4)将步骤3得到的滤渣放入烘箱中60℃烘12h得到除PVDF再生的磷酸铁锂粉。
(5)将步骤3得到的滤液70℃旋蒸，真空度为-0.1MPa，回收乙醇，得到1-乙基-3-甲基咪唑四氟硼酸盐和PVDF的混合物。
(6)将步骤5得到的混合物抽滤，回收1-乙基-3-甲基咪唑四氟硼酸盐和PVDF。
(7)将步骤4得到的除PVDF的磷酸铁锂粉，叔丁醇(液固比＝8mL/g)，质量为磷酸铁锂粉10wt％的1-乙基-3-甲基咪唑四氟硼酸盐作催化剂加入烧瓶于油浴锅中85℃加热回流2h，使铝尽可能完全转化为叔丁醇铝。
(8)待铝转化为叔丁醇铝后，继续85℃加热30min，将叔丁醇溶剂蒸出并回收，再升高温度至160℃加热60min，蒸出叔丁醇铝得到除PVDF除铝的磷酸铁锂粉。
(9)将步骤8得到的混合物抽滤，得到纯化后的磷酸铁锂粉并回收1-乙基-3-甲基咪唑四氟硼酸盐。
一种锂离子电池回收的方法，包括上述磷酸铁锂正极材料除PVDF除铝的方法的步骤。
实施例3
一种磷酸铁锂正极材料除PVDF除铝的方法，包括以下步骤：
(1)将废旧磷酸铁锂电池进行放电、拆解和破碎处理得到废旧磷酸铁锂正极材料。
(2)将步骤1得到的磷酸铁锂粉，质量为磷酸铁锂粉15wt％的1-乙基-3-甲基咪唑六氟磷酸盐，乙醇(液固比＝5mL/g)装入球磨罐中,向球磨罐内加入球料比为10:1的锆球，置于行星球磨机上以400rpm球磨480min得到磷酸铁锂混合物。
(3)将步骤2得到的磷酸铁锂混合物用质量比为磷酸铁锂5倍的乙醇洗涤再抽滤，重复3次。
(4)将步骤3得到的滤渣放入烘箱中80℃烘4h得到除PVDF再生的磷酸铁锂粉。
(5)将步骤3得到的滤液80℃下，真空度为-0.1MPa旋蒸回收乙醇，得到1-乙基-3-甲基咪唑六氟磷酸盐和PVDF的混合物。
(6)将步骤5得到的混合物抽滤，回收1-乙基-3-甲基咪唑六氟磷酸盐和PVDF。
(7)将步骤4得到的除PVDF的磷酸铁锂粉，正丙醇(液固比＝10mL/g)，质量为磷酸铁锂粉15wt％的1-乙基-3-甲基咪唑六氟磷酸盐作催化剂加入烧瓶于油浴锅中100℃加热回流3h，使铝尽可能完全转化为正丙醇铝。
(8)待铝转化为正丙醇铝后，继续100℃加热40min，将正丙醇蒸出并回收，再将温度升高到170℃加热40min，蒸出正丙醇铝得到除PVDF除铝的磷酸铁锂粉。
(9)将步骤8得到的混合物抽滤，得到纯化后的磷酸铁锂粉并回收1-乙基-3-甲基咪唑六氟磷酸盐。
一种锂离子电池回收的方法，包括上述磷酸铁锂正极材料除PVDF除铝的方法的步骤。
对比例1
与实施例1的区别仅在于：步骤2中加入质量为磷酸铁锂粉2wt％的1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺。
对比例2
与实施例1的区别仅在于：步骤7中异丙醇与除PVDF的磷酸铁锂粉的液固比＝3mL/g。
对比例3
与实施例1的区别仅在于：步骤2和步骤7中离子液体替换为1-乙基-3-甲基咪唑氯盐。
试验例
表1为废旧磷酸铁锂材料、实施例1、2、3和对比例1、2、3制备的磷酸铁锂产品的Fe、Li和Al含量(具体数据是由ICP-AES设备测试得到)，P含量(具体数据是由滴定得到)和F含量(具体数据是由电位法测试得到)的测试数据表。由表1可知，实施例中制备得到磷酸铁锂中Fe、P和Li含量表现正常，F含量和Al含量得到有效降低，符合磷酸铁锂锂电池工业生产标准。其中实施例1制备得到的磷酸铁锂中Al含量由2.1％降到0.04％，F含量由0.2％降到0.002％。对比例1相对于实施例1，步骤2中加入更少的1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺，制备得到的磷酸铁锂粉中还有较多PVDF残留，F含量为0.12％；对比例2相对于实施例1，步骤7中加入更少的异丙醇，制备得到的磷酸铁锂粉中还有较多Al残留，Al含量为1.3％；对比例3相对于实施例1，采用不含氟的离子液体，制备得到的磷酸铁锂粉中F和Al含量基本没有降低，F含量为0.2％，Al含量为2.08％。
表1元素含量测试数据表

电化学性能：
表2为实施例1、2、3与原料制备得到磷酸铁锂电池的电化学性能，具体数据是通过电化学工作站等设备测试得到。由表2可知，实施例中得到的除PVDF修复再生后的磷酸铁锂产品电化学性能相比原料有所提升，其中实施例1的充电容量可以达到158.6mAh/g，放电容量可以达到152.6mAh/g，计算得到首次充放电效率＝放电容量/充电容量＝96.2％。
表2电化学测试数据表

Claims (15)

  1. 一种磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，包括以下步骤：
    S1：将磷酸铁锂粉、第一离子液体及乙醇进行混合球磨，固液分离，得到除PVDF的磷酸铁锂粉；
    S2：将醇、第二离子液体及步骤S1制得的所述除PVDF的磷酸铁锂粉进行混合加热，分离醇和铝醇盐，得到除PVDF除铝的磷酸铁锂粉；
    其中，步骤S1、S2中所述第一离子液体、第二离子液体独立选自含氟离子液体。
  2. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S1中，所述磷酸铁锂粉由废旧磷酸铁锂电池进行放电、拆解及破碎处理后获得。
  3. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S1、S2中，所述第一离子液体、第二离子液体独立选自1-乙基-3-甲基咪唑双三氟甲基磺酰亚胺、1-乙基-3-甲基咪唑四氟硼酸盐、1-乙基-3-甲基咪唑六氟磷酸盐、1-乙基-3-甲基咪唑双(氟磺酰)亚胺盐、1-乙基-3-甲基咪唑三氟乙酸盐或1-乙基-3-甲基咪唑三氟甲磺酸盐中的至少一种。
  4. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S1中，所述第一离子液体的质量为所述磷酸铁锂粉质量的5～20％。
  5. 根据权利要求1或4所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S1中，所述乙醇与所述磷酸铁锂粉的液固比为2～5mL/g。
  6. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S1中，所述球磨的工艺参数为：球料比为(4～10)：1；转速为300～400rpm；时间为120～480min。
  7. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S1中，所述固液分离包括：将球磨后的混合物进行洗涤，分离洗涤后液，得到除PVDF的磷酸铁锂粉。
  8. 根据权利要求1或7所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于， 步骤S1中，固液分离后的液相进行旋蒸，再次固液分离后得到离子液体和PVDF。
  9. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S2中，所述醇为正丙醇、异丙醇、正丁醇、异丁醇、仲丁醇或叔丁醇中的至少一种。
  10. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S2中，所述醇与所述除PVDF的磷酸铁锂粉的液固比为5～10mL/g。
  11. 根据权利要求1或10所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S2中，所述第二离子液体的质量为所述除PVDF的磷酸铁锂粉的质量的5～20％。
  12. 根据权利要求1所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，步骤S2中，所述加热分离醇和铝醇盐包括：先进行一次加热，生成铝醇盐，再进行二次加热，依次分离醇和铝醇盐。
  13. 根据权利要求12所述的磷酸铁锂正极材料除PVDF除铝的方法，其特征在于，所述一次加热的温度为80～120℃；所述一次加热的时间为60-180min；所述二次加热的温度为80～180℃；所述二次加热的时间为60～120min。
  14. 一种锂离子电池回收的方法，包括权利要求1-13任一项所述的磷酸铁锂正极材料除PVDF除铝的方法的步骤。
  15. 权利要求1-13任一项所述的的磷酸铁锂正极材料除PVDF除铝的方法在锂离子电池回收中的应用。
PCT/CN2023/112596 2023-08-11 2023-08-11 一种磷酸铁锂正极材料除pvdf除铝的方法 Pending WO2025035278A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/CN2023/112596 WO2025035278A1 (zh) 2023-08-11 2023-08-11 一种磷酸铁锂正极材料除pvdf除铝的方法
CN202380011476.2A CN117295685B (zh) 2023-08-11 2023-08-11 一种磷酸铁锂正极材料除pvdf除铝的方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2023/112596 WO2025035278A1 (zh) 2023-08-11 2023-08-11 一种磷酸铁锂正极材料除pvdf除铝的方法

Publications (1)

Publication Number Publication Date
WO2025035278A1 true WO2025035278A1 (zh) 2025-02-20

Family

ID=89259010

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2023/112596 Pending WO2025035278A1 (zh) 2023-08-11 2023-08-11 一种磷酸铁锂正极材料除pvdf除铝的方法

Country Status (2)

Country Link
CN (1) CN117295685B (zh)
WO (1) WO2025035278A1 (zh)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN120728063A (zh) * 2025-06-17 2025-09-30 杭州爱思博特新能源科技有限公司 一种失效磷酸铁锂的高效直接再生方法
CN121282413B (zh) * 2025-12-04 2026-04-17 湖南裕能新能源电池材料股份有限公司 基于定向氧化焙烧的磷酸铁锂正极材料预处理方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012121780A (ja) * 2010-12-10 2012-06-28 Sumitomo Metal Mining Co Ltd 酸化リチウムの製造方法
CN111440945A (zh) * 2020-05-18 2020-07-24 中国科学院过程工程研究所 一种离子液体法稀土钆精制除铝的方法
CN112897492A (zh) * 2021-01-25 2021-06-04 中南大学 一种高杂质的磷酸铁锂废粉再生循环的方法
CN114725553A (zh) * 2022-03-14 2022-07-08 中南大学 一种废旧锂电池铝箔和正极材料的分离方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT187095B (de) * 1953-03-04 1956-10-10 Hoechst Ag Verfahren zum Wasserabstoßendmachen von Fasergut
JP2009292803A (ja) * 2008-05-07 2009-12-17 Muroran Institute Of Technology 金属アルコキシドの製造方法
CN108448058B (zh) * 2018-01-31 2021-12-17 华南理工大学 一种锂金属电池锂负极的表面修饰改性方法及锂金属电池
CN115353086A (zh) * 2022-10-15 2022-11-18 株洲冶炼集团股份有限公司 一种高效预处理废旧磷酸铁锂正极材料的火法回收方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012121780A (ja) * 2010-12-10 2012-06-28 Sumitomo Metal Mining Co Ltd 酸化リチウムの製造方法
CN111440945A (zh) * 2020-05-18 2020-07-24 中国科学院过程工程研究所 一种离子液体法稀土钆精制除铝的方法
CN112897492A (zh) * 2021-01-25 2021-06-04 中南大学 一种高杂质的磷酸铁锂废粉再生循环的方法
CN114725553A (zh) * 2022-03-14 2022-07-08 中南大学 一种废旧锂电池铝箔和正极材料的分离方法

Also Published As

Publication number Publication date
CN117295685B (zh) 2025-11-14
CN117295685A (zh) 2023-12-26

Similar Documents

Publication Publication Date Title
JP7371263B2 (ja) 正極スクラップを用いた活物質の再使用方法
Chen et al. Co-precipitation preparation of Ni-Co-Mn ternary cathode materials by using the sources extracting directly from spent lithium-ion batteries
Xu et al. Direct recovery of degraded LiFePO4 cathode via mild chemical relithiation strategy
CN111270072B (zh) 一种废旧磷酸铁锂电池正极材料的回收利用方法
CN113846235B (zh) 一种锂离子电池中锂的闭环回收再利用方法
Xu et al. The regeneration of graphite anode from spent lithium-ion batteries by washing with a nitric acid/ethanol solution
CN110620278A (zh) 一种废旧磷酸铁锂电池正极材料的回收方法
KR102760864B1 (ko) 양극 스크랩을 이용한 활물질 재사용 방법
CN117295685B (zh) 一种磷酸铁锂正极材料除pvdf除铝的方法
CN103449395A (zh) 一种从水系废旧磷酸铁锂电池中回收再生正极材料的方法
Natarajan et al. Environmentally friendly regeneration of graphite from spent lithium-ion batteries for sustainable anode material reuse
CN108083270A (zh) 一种石墨负极废料的修复再生方法
Li et al. A facile approach for regeneration of graphite anodes from spent lithium-ion battery
Ren et al. Sustainable reprocessing of lithium iron phosphate batteries: A recovery approach using liquid-phase method at reduced temperature
Zhang et al. Effective stripping and reutilization of LiFePO4 cathode waste from retired lithium ion batteries
Gao et al. Graphite regenerating from retired (LFP) lithium-ion battery: Phase transformation mechanism of impurities in low-temperature sulfation roasting process
Lu et al. Oxygen-rich modified-graphite recycled from spent lithium batteries for improved lithium-ion storage: Adsorption and intercalation mechanisms
Lu et al. Unveiling residual charge effects in the direct regeneration of spent LiFePO4
CN116581412A (zh) 一种锂离子电池的回收修复方法及电池
CN118373396B (zh) 废旧磷酸铁锂正极材料的修复再生方法
CN117374281A (zh) 从废旧电池中再生的负极活性材料及其再生方法和应用
CN119591070A (zh) 一种负极锂及废旧隔膜辅助再生磷酸铁锂正极材料的方法
CN118738632A (zh) 一种电池负极石墨材料的绿色回收再生方法
Wu et al. Using green deep eutectic solvents for targeted regeneration to improve the cycle life of spent lithium iron phosphate batteries
CN117361541A (zh) 从废旧锂离子电池中回收修复的硅碳负极材料及其方法和应用

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 202380011476.2

Country of ref document: CN

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

Ref document number: 23948716

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE