CN110723718A - A kind of preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery - Google Patents

A kind of preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery Download PDF

Info

Publication number
CN110723718A
CN110723718A CN201911048791.4A CN201911048791A CN110723718A CN 110723718 A CN110723718 A CN 110723718A CN 201911048791 A CN201911048791 A CN 201911048791A CN 110723718 A CN110723718 A CN 110723718A
Authority
CN
China
Prior art keywords
lithium
preparation
source
composite material
nitrogen
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.)
Granted
Application number
CN201911048791.4A
Other languages
Chinese (zh)
Other versions
CN110723718B (en
Inventor
汪炳叔
杨玉明
许俊锋
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.)
Fuzhou University
Original Assignee
Fuzhou University
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 Fuzhou University filed Critical Fuzhou University
Priority to CN201911048791.4A priority Critical patent/CN110723718B/en
Publication of CN110723718A publication Critical patent/CN110723718A/en
Application granted granted Critical
Publication of CN110723718B publication Critical patent/CN110723718B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00Phosphorus; Compounds thereof
    • C01B25/16Oxyacids of phosphorus; Salts thereof
    • C01B25/26Phosphates
    • C01B25/45Phosphates containing plural metal, or metal and ammonium
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00Carbon; Compounds thereof
    • C01B32/15Nano-sized carbon materials
    • C01B32/182Graphene
    • C01B32/184Preparation
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • H01M10/0525Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/58Selection 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
    • H01M4/5825Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/62Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624Electric conductive fillers
    • H01M4/625Carbon or graphite
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2204/00Structure or properties of graphene
    • C01B2204/20Graphene characterized by its properties
    • C01B2204/22Electronic properties
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/01Particle morphology depicted by an image
    • C01P2004/03Particle morphology depicted by an image obtained by SEM
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00Physical properties of inorganic compounds
    • C01P2006/40Electric properties
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Landscapes

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

Abstract

The invention discloses a preparation method of a nitrogen-doped graphene/lithium iron phosphate composite material. The method has simple process, is suitable for industrial mass production, and the prepared composite material has excellent and stable conductivity, can be used as a positive electrode material and applied to lithium ion batteries.

Description

一种用于锂离子电池的氮掺杂石墨烯/磷酸铁锂复合材料的 制备方法A kind of preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery

技术领域technical field

本发明属于复合材料领域,具体涉及一种用于锂离子电池的氮掺杂石墨烯/磷酸铁锂复合材料的制备方法。The invention belongs to the field of composite materials, in particular to a method for preparing a nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion batteries.

背景技术Background technique

锂离子电池是新一代的绿色高能电池。锂离子电池自商品化以来,正极材料导电性的研究一直是电池领域研究的热点,目前用于锂离子电池的正极活性材料多为过渡金属氧化物或者过渡金属磷酸盐,它们大部分都是半导体或者绝缘体,导电性能较差,因此需要加入导电剂来改善导电性,在活性物质之间、活性物质与集流体中起到收集微电流的作用,以减小电极的接触电阻,同时也能有效地提高锂离子在电池材料中的迁移率,从而提高电池的充放电倍率性能。Lithium-ion batteries are a new generation of green high-energy batteries. Since the commercialization of lithium-ion batteries, the research on the conductivity of cathode materials has always been a hot spot in the battery field. At present, the cathode active materials used in lithium-ion batteries are mostly transition metal oxides or transition metal phosphates, most of which are semiconductors. Or insulators have poor electrical conductivity, so it is necessary to add conductive agents to improve electrical conductivity, and play a role in collecting microcurrent between active materials, active materials and current collectors to reduce the contact resistance of electrodes, and also effectively Therefore, the mobility of lithium ions in the battery material can be greatly improved, thereby improving the charge-discharge rate performance of the battery.

CN 106992301A公开了一种氮掺杂石墨烯导电剂及其制备方法,采用化学气相沉积法制备氮掺杂石墨烯并应用于锂离子电池中,虽然该方法成功制备了导电性高的导电剂,但在浆料制备过程中存在导电剂分散问题,石墨烯容易团聚使电池内阻变大,从而降低电池的性能。CN 109103442A公开了一种石墨烯包覆磷酸铁锂正极材料的制备方法,采用微波水热法制备石墨烯包覆磷酸铁锂材料,通过包覆解决了石墨烯分散的问题,但是该方法制备的石墨烯导电性不高,因此在改善磷酸铁锂电池性能方面效果并不理想。CN 106992301A discloses a nitrogen-doped graphene conductive agent and a preparation method thereof. The nitrogen-doped graphene is prepared by chemical vapor deposition and applied to a lithium ion battery. Although the method successfully prepares a conductive agent with high conductivity, However, there is a problem of dispersion of the conductive agent during the preparation of the slurry, and the graphene is easy to agglomerate, which increases the internal resistance of the battery, thereby reducing the performance of the battery. CN 109103442A discloses a preparation method of graphene-coated lithium iron phosphate positive electrode material. The graphene-coated lithium iron phosphate material is prepared by microwave hydrothermal method, and the problem of graphene dispersion is solved by coating. Graphene is not very conductive, so it is not ideal for improving the performance of lithium iron phosphate batteries.

发明内容SUMMARY OF THE INVENTION

为解决现有技术的不足,本发明提供了一种用于锂离子电池的氮掺杂石墨烯/磷酸铁锂复合材料的制备方法,该复合材料的制备方法包括采用溶胶凝胶法制备磷酸铁锂与碳源复合材料的前驱体,之后在氨气气氛下采用高温煅烧法得到氮掺杂石墨烯/磷酸铁锂复合材料。既解决了石墨烯分散不均匀的问题,还通过对石墨烯进行氮改性进一步提高材料的导电性。In order to solve the deficiencies of the prior art, the present invention provides a preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery, the preparation method of the composite material includes preparing iron phosphate by a sol-gel method The precursor of the lithium and carbon source composite material is then calcined at a high temperature in an ammonia atmosphere to obtain a nitrogen-doped graphene/lithium iron phosphate composite material. It not only solves the problem of uneven dispersion of graphene, but also further improves the conductivity of the material by nitrogen modification of graphene.

为实现本发明的目的,本发明的技术方案是:For realizing the purpose of the present invention, the technical scheme of the present invention is:

一种用于锂离子电池的氮掺杂石墨烯/磷酸铁锂复合材料的制备方法,以碳源、锂源、磷源和铁源为原料,通过溶胶凝胶法和高温煅烧法制备氮掺杂石墨烯/磷酸铁锂复合材料,具体包括以下步骤:A method for preparing nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion batteries, using carbon source, lithium source, phosphorus source and iron source as raw materials, and preparing nitrogen-doped graphene through a sol-gel method and a high-temperature calcination method The heterographene/lithium iron phosphate composite material specifically includes the following steps:

(1)将锂源、磷源、铁源以及碳源加入到去离子水中分散,制备成分散液;(1) adding lithium source, phosphorus source, iron source and carbon source into deionized water to disperse, and prepare a dispersion liquid;

(2)在步骤(1)的分散液加入柠檬酸并使用氨水调节pH至11,搅拌均匀;(2) add citric acid in the dispersion of step (1) and use ammoniacal liquor to adjust pH to 11, stir evenly;

(3)在一定温度下进行水浴加热,搅拌至出现凝胶;(3) heating in a water bath at a certain temperature, stirring until gel appears;

(4) 在氨气气氛下,对步骤(3)得到的凝胶进行高温煅烧,得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) In an ammonia atmosphere, the gel obtained in step (3) is calcined at high temperature to obtain a nitrogen-doped graphene/lithium iron phosphate composite material.

进一步地,步骤(1)所述的锂源、磷源、铁源、碳源之间的摩尔比为0.8-1.2:1-1.5:1-1.5:0.5-3。Further, the molar ratio among the lithium source, phosphorus source, iron source and carbon source described in step (1) is 0.8-1.2:1-1.5:1-1.5:0.5-3.

进一步地,步骤(1)所述的制备分散液的方法为大功率超声分散,功率在800W-1000W。Further, the method for preparing the dispersion described in step (1) is high-power ultrasonic dispersion, and the power is 800W-1000W.

进一步地,步骤(1)中所述的锂源为氢氧化锂、碳酸锂、磷酸氢锂中的一种。Further, the lithium source described in step (1) is one of lithium hydroxide, lithium carbonate and lithium hydrogen phosphate.

进一步地,步骤(1)中所述的磷源为磷酸铵、磷酸氢二铵、磷酸一氢铵、磷酸中的一种。Further, the phosphorus source described in step (1) is one of ammonium phosphate, diammonium hydrogen phosphate, ammonium monohydrogen phosphate, and phosphoric acid.

进一步地,步骤(1)所述的铁源为硫酸亚铁、磷酸铁、氧化铁、氯化铁、乙酸铁中的一种。Further, the iron source described in step (1) is one of ferrous sulfate, ferric phosphate, ferric oxide, ferric chloride, and ferric acetate.

进一步地,步骤(1)所述的碳源为葡萄糖、果糖、蔗糖中的一种。Further, the carbon source in step (1) is one of glucose, fructose and sucrose.

进一步地,步骤(3)中所述的水浴加热温度为80-100 ℃。Further, the heating temperature of the water bath described in step (3) is 80-100 °C.

进一步地,步骤(4)中所述的氨气为高纯氨气。Further, the ammonia gas described in step (4) is high-purity ammonia gas.

进一步地,步骤(4)中所述的煅烧过程分为两段,第一段在600℃保温3-5h,第二段在750-900℃保温3-5h,升温速率为3-5℃/min。Further, the calcination process described in step (4) is divided into two stages, the first stage is kept at 600°C for 3-5h, the second stage is kept at 750-900°C for 3-5h, and the heating rate is 3-5°C/ min.

相较于现有技术,本发明具有如下的有益效果:Compared with the prior art, the present invention has the following beneficial effects:

本发明提供的氮掺杂石墨烯/磷酸铁锂复合材料,该复合材料的制备方法包括采用溶胶凝胶法制备磷酸铁锂与碳源复合材料的前驱体,之后在氨气气氛下采用高温煅烧法得到氮掺杂石墨烯/磷酸铁锂复合材料。通过高温煅烧,将葡萄糖热解还原成氮掺杂石墨烯,凝胶干燥成磷酸铁锂,并且在还原过程中氮掺杂石墨烯与磷酸铁锂复合。该制备工艺简单,通过该方法既能解决石墨烯在正极浆料中分散不均匀的问题,又在石墨烯的基础上对其进行氮改性,进一步提高其导电性,从而提高磷酸铁锂电池的充放电以及倍率性能。The nitrogen-doped graphene/lithium iron phosphate composite material provided by the present invention, the preparation method of the composite material includes preparing the precursor of the lithium iron phosphate and carbon source composite material by a sol-gel method, and then calcining at a high temperature in an ammonia gas atmosphere The nitrogen-doped graphene/lithium iron phosphate composite material was obtained by the method. Through high-temperature calcination, glucose is pyrolytically reduced to nitrogen-doped graphene, the gel is dried to form lithium iron phosphate, and the nitrogen-doped graphene is recombined with lithium iron phosphate during the reduction process. The preparation process is simple, and the method can not only solve the problem of uneven dispersion of graphene in the positive electrode slurry, but also carry out nitrogen modification on the basis of graphene to further improve its conductivity, thereby improving the lithium iron phosphate battery. charge-discharge and rate performance.

附图说明Description of drawings

图1为实施例1的锂离子电池在1C下循环100次后容量保持率;1 shows the capacity retention rate of the lithium-ion battery of Example 1 after being cycled 100 times at 1C;

图2为氮掺杂石墨烯/磷酸铁锂复合材料SEM图。Figure 2 is a SEM image of nitrogen-doped graphene/lithium iron phosphate composite material.

具体实施方式Detailed ways

结合实施例,对本发明具体较优实施作进一步说明:In conjunction with the embodiments, the specific preferred implementation of the present invention will be further described:

实施例1Example 1

一种氮掺杂石墨烯/磷酸铁锂复合材料制备方法,包括如下步骤:A method for preparing nitrogen-doped graphene/lithium iron phosphate composite material, comprising the following steps:

(1)按照锂源:磷源:铁源=1:1:1:1的摩尔比,称取0.01mol氢氧化锂、0.01mol磷酸氢二铵、0.01mol氯化铁与0.01mol葡萄糖加入去离子水中通过高功率分散制备分散液;(1) According to the molar ratio of lithium source: phosphorus source: iron source = 1:1:1:1, weigh 0.01mol lithium hydroxide, 0.01mol diammonium hydrogen phosphate, 0.01mol ferric chloride and 0.01mol glucose and add to Dispersion is prepared by high-power dispersion in ionized water;

(2)搅拌过程中加入0.06mol柠檬酸,并且加入氨水调节PH至11;(2) Add 0.06mol citric acid during stirring, and add ammonia water to adjust pH to 11;

(3)在80℃下水浴加热,搅拌至呈凝胶状,得到磷酸铁锂/石墨烯复合材料前驱体;(3) Heating in a water bath at 80°C and stirring until gel-like to obtain the precursor of lithium iron phosphate/graphene composite material;

(4)将步骤(3)得到的材料转入真空加热炉中,通入高纯氨气,以3℃/min的升温速率,升温至600℃保温3h后再将温度提升至750℃保温3h,最后冷却至室温得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) Transfer the material obtained in step (3) into a vacuum heating furnace, pass in high-purity ammonia gas, heat up to 600 °C for 3 hours at a heating rate of 3 °C/min, and then raise the temperature to 750 °C for 3 hours. , and finally cooled to room temperature to obtain nitrogen-doped graphene/lithium iron phosphate composites.

将所得复合材料分散于N-甲基吡咯烷酮(NMP)中得到分散液。按PVDF:NMP=5:95质量比混合得到PVDF粘结剂,将粘结剂与分散液按照1:8比例混合搅拌,得到锂离子电池正极浆料。The obtained composite material was dispersed in N-methylpyrrolidone (NMP) to obtain a dispersion. The PVDF binder is obtained by mixing the PVDF:NMP=5:95 mass ratio, and the binder and the dispersion liquid are mixed and stirred according to the ratio of 1:8 to obtain the positive electrode slurry of the lithium ion battery.

实施例2Example 2

一种氮掺杂石墨烯/磷酸铁锂复合材料制备方法,包括如下步骤:A method for preparing nitrogen-doped graphene/lithium iron phosphate composite material, comprising the following steps:

(1)按照锂源:磷源:铁源=1:1:1:2的摩尔比,称取0.01mol乙酸锂、0.01mol磷酸铵、0.01mol乙酸铁与0.02mol葡萄糖加入去离子水中通过高功率分散制备分散液;(1) According to the molar ratio of lithium source: phosphorus source: iron source = 1:1:1:2, weigh 0.01mol lithium acetate, 0.01mol ammonium phosphate, 0.01mol ferric acetate and 0.02mol glucose into deionized water and pass through high Power dispersion to prepare dispersion;

(2)搅拌过程中加入0.06mol柠檬酸,并且加入氨水调节PH至11;(2) Add 0.06mol citric acid during stirring, and add ammonia water to adjust pH to 11;

(3)在90℃下水浴加热,搅拌至呈凝胶状,得到磷酸铁锂/石墨烯复合材料前驱体;(3) Heating in a water bath at 90°C and stirring until gel-like to obtain the precursor of lithium iron phosphate/graphene composite material;

(4)将步骤(3)得到的材料转入真空加热炉中,通入高纯氨气,以4℃/min的升温速率,升温至600℃保温3h后再将温度提升至700℃保温3h,最后冷却至室温得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) Transfer the material obtained in step (3) into a vacuum heating furnace, pass in high-purity ammonia gas, heat up to 600°C for 3 hours at a heating rate of 4°C/min, and then raise the temperature to 700°C for 3 hours , and finally cooled to room temperature to obtain nitrogen-doped graphene/lithium iron phosphate composites.

将所得复合材料分散于N-甲基吡咯烷酮(NMP)中得到分散液。按PVDF:NMP=5:95质量比混合得到PVDF粘结剂,将粘结剂与分散液按照1:8比例混合搅拌,得到锂离子电池正极浆料。The obtained composite material was dispersed in N-methylpyrrolidone (NMP) to obtain a dispersion. The PVDF binder is obtained by mixing the PVDF:NMP=5:95 mass ratio, and the binder and the dispersion liquid are mixed and stirred according to the ratio of 1:8 to obtain the positive electrode slurry of the lithium ion battery.

实施例3Example 3

一种氮掺杂石墨烯/磷酸铁锂复合材料制备方法,包括如下步骤:A method for preparing nitrogen-doped graphene/lithium iron phosphate composite material, comprising the following steps:

(1)按照锂源:磷源:铁源=1:1:1:3的摩尔比,称取0.01mol乙酸锂、0.01mol磷酸一氢铵、0.01mol乙酸铁与0.03mol葡萄糖加入去离子水中通过高功率分散制备分散液;(1) According to the molar ratio of lithium source: phosphorus source: iron source = 1:1:1:3, weigh 0.01mol lithium acetate, 0.01mol ammonium monohydrogen phosphate, 0.01mol iron acetate and 0.03mol glucose into deionized water Preparation of dispersions by high power dispersion;

(2)搅拌过程中加入0.06mol柠檬酸,并且加入氨水调节PH至11;(2) Add 0.06mol citric acid during stirring, and add ammonia water to adjust pH to 11;

(3)100℃下水浴加热,搅拌至呈凝胶状,得到磷酸铁锂/石墨烯复合材料前驱体;(3) Heating in a water bath at 100°C, stirring until gel-like, to obtain the precursor of lithium iron phosphate/graphene composite material;

(4)将步骤(3)得到的材料转入真空加热炉中,通入高纯氨气,以5℃/min的升温速率,升温至600℃保温3h后再将温度提升至800℃保温3h,最后冷却至室温得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) Transfer the material obtained in step (3) into a vacuum heating furnace, pass in high-purity ammonia gas, heat up to 600°C for 3 hours at a heating rate of 5°C/min, and then raise the temperature to 800°C for 3 hours , and finally cooled to room temperature to obtain nitrogen-doped graphene/lithium iron phosphate composites.

将所得复合材料分散于N-甲基吡咯烷酮(NMP)中得到分散液。按PVDF:NMP=5:95质量比混合得到PVDF粘结剂,将粘结剂与分散液按照1:8比例混合搅拌,得到锂离子电池正极浆料。The obtained composite material was dispersed in N-methylpyrrolidone (NMP) to obtain a dispersion. The PVDF binder is obtained by mixing the PVDF:NMP=5:95 mass ratio, and the binder and the dispersion liquid are mixed and stirred according to the ratio of 1:8 to obtain the positive electrode slurry of the lithium ion battery.

实施例4Example 4

一种氮掺杂石墨烯/磷酸铁锂复合材料制备方法,包括如下步骤:A method for preparing nitrogen-doped graphene/lithium iron phosphate composite material, comprising the following steps:

(1)按照锂源:磷源:铁源=1:1:1:1的摩尔比,称取0.01mol乙酸锂、0.01mol磷酸一氢铵、0.01mol乙酸铁与0.01mol葡萄糖加入去离子水中通过高功率分散制备分散液;(1) According to the molar ratio of lithium source: phosphorus source: iron source = 1:1:1:1, weigh 0.01mol lithium acetate, 0.01mol ammonium monohydrogen phosphate, 0.01mol iron acetate and 0.01mol glucose into deionized water Preparation of dispersions by high power dispersion;

(2)搅拌过程中加入0.06mol柠檬酸,并且加入氨水调节PH至11;(2) Add 0.06mol citric acid during stirring, and add ammonia water to adjust pH to 11;

(3)80℃下水浴加热,搅拌至呈凝胶状,得到磷酸铁锂/石墨烯复合材料前驱体;(3) Heating in a water bath at 80°C, stirring until gel-like, to obtain the precursor of lithium iron phosphate/graphene composite material;

(4)将步骤(3)得到的材料转入真空加热炉中,通入高纯氨气,以5℃/min的升温速率,升温至600℃保温3h后再将温度提升至900℃保温3h,最后冷却至室温得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) Transfer the material obtained in step (3) into a vacuum heating furnace, pass in high-purity ammonia gas, heat up to 600°C for 3 hours at a heating rate of 5°C/min, and then raise the temperature to 900°C for 3 hours , and finally cooled to room temperature to obtain nitrogen-doped graphene/lithium iron phosphate composites.

将所得复合材料分散于N-甲基吡咯烷酮(NMP)中得到分散液。按PVDF:NMP=5:95质量比混合得到PVDF粘结剂,将粘结剂与分散液按照1:8比例混合搅拌,得到锂离子电池正极浆料。The obtained composite material was dispersed in N-methylpyrrolidone (NMP) to obtain a dispersion. The PVDF binder is obtained by mixing the PVDF:NMP=5:95 mass ratio, and the binder and the dispersion liquid are mixed and stirred according to the ratio of 1:8 to obtain the positive electrode slurry of the lithium ion battery.

实施例5Example 5

一种氮掺杂石墨烯/磷酸铁锂复合材料制备方法,包括如下步骤:A method for preparing nitrogen-doped graphene/lithium iron phosphate composite material, comprising the following steps:

(1)按照锂源:磷源:铁源=1:1:1:1的摩尔比,称取0.01mol乙酸锂、0.01mol磷酸一氢铵、0.01mol乙酸铁与0.01mol葡萄糖加入去离子水中通过高功率分散制备分散液;(1) According to the molar ratio of lithium source: phosphorus source: iron source = 1:1:1:1, weigh 0.01mol lithium acetate, 0.01mol ammonium monohydrogen phosphate, 0.01mol iron acetate and 0.01mol glucose into deionized water Preparation of dispersions by high power dispersion;

(2)搅拌过程中加入0.06mol柠檬酸,并且加入氨水调节PH至11;(2) Add 0.06mol citric acid during stirring, and add ammonia water to adjust pH to 11;

(3)90℃下水浴加热,搅拌至呈凝胶状,得到磷酸铁锂/石墨烯复合材料前驱体;(3) Heating in a water bath at 90°C, stirring until gel-like, to obtain a precursor of lithium iron phosphate/graphene composite material;

(4)将步骤(3)得到的材料转入真空加热炉中,通入高纯氨气,以5℃/min的升温速率,升温至600℃保温3h后再将温度提升至900℃保温3h,最后冷却至室温得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) Transfer the material obtained in step (3) into a vacuum heating furnace, pass in high-purity ammonia gas, heat up to 600°C for 3 hours at a heating rate of 5°C/min, and then raise the temperature to 900°C for 3 hours , and finally cooled to room temperature to obtain nitrogen-doped graphene/lithium iron phosphate composites.

将所得复合材料分散于N-甲基吡咯烷酮(NMP)中得到分散液。按PVDF:NMP=5:95质量比混合得到PVDF粘结剂,将粘结剂与分散液按照0.5:9比例混合搅拌,得到锂离子电池正极浆料。The obtained composite material was dispersed in N-methylpyrrolidone (NMP) to obtain a dispersion. The PVDF binder is obtained by mixing the PVDF:NMP=5:95 mass ratio, and the binder and the dispersion liquid are mixed and stirred according to the ratio of 0.5:9 to obtain the positive electrode slurry of the lithium ion battery.

将实例1-5制备的正极浆料,中间相碳微球作为负极材料,应用于锂电中,组装成扣式电池。The positive electrode slurry prepared in Examples 1-5 and the mesophase carbon microspheres were used as negative electrode materials, which were applied to lithium batteries and assembled into a button battery.

表1 各实施例氮掺杂石墨烯/磷酸铁锂复合材料1 C下100次循环后的放电容量以及库伦效率Table 1 The discharge capacity and coulombic efficiency of nitrogen-doped graphene/lithium iron phosphate composites of each embodiment after 100 cycles at 1 C

表1可以看出,使用所述方法制备的氮掺杂石墨烯/磷酸铁锂复合材料制备成正极导电浆料应用于锂离子电池(1-5)在高倍率下具有更高的容量保持率以及库伦效率,并且实例1在低倍率(0.5C)下比容量达到 165mAh/g,接近理论比容量;图1为实例1在1C电流密度下循环100次的循环图,使用该制备方法制备的复合材料在多次循环后仍能保持较高的容量保持率。It can be seen from Table 1 that the nitrogen-doped graphene/lithium iron phosphate composite material prepared by the method is prepared as a positive electrode conductive paste and applied to lithium ion batteries (1-5), which has a higher capacity retention rate at high rates and Coulombic efficiency, and the specific capacity of Example 1 reaches 165mAh/g at low rate (0.5C), which is close to the theoretical specific capacity; Figure 1 is the cycle diagram of Example 1 under 1C current density for 100 cycles, prepared using this preparation method The composites maintained high capacity retention after multiple cycles.

Claims (9)

1.一种用于锂离子电池的氮掺杂石墨烯/磷酸铁锂复合材料的制备方法,其特征在于包括以下步骤:1. a preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery, is characterized in that comprising the following steps: (1)将锂源、磷源、铁源以及碳源加入到去离子水中分散,制备成分散液;(1) adding lithium source, phosphorus source, iron source and carbon source into deionized water to disperse, and prepare a dispersion liquid; (2)在步骤(1)的分散液中加入柠檬酸并使用氨水调节pH至11,搅拌均匀;(2) in the dispersion liquid of step (1), add citric acid and use ammoniacal liquor to adjust pH to 11, stir; (3)在一定温度下进行水浴加热,搅拌至出现凝胶;(3) heating in a water bath at a certain temperature, stirring until gel appears; (4) 在氨气气氛下,对步骤(3)得到的凝胶进行高温煅烧,得到氮掺杂石墨烯/磷酸铁锂复合材料。(4) In an ammonia atmosphere, the gel obtained in step (3) is calcined at high temperature to obtain a nitrogen-doped graphene/lithium iron phosphate composite material. 2.根据权利要求1所述的制备方法,其特征在于:步骤(1)所述的锂源、磷源、铁源、碳源之间的摩尔比为0.8-1.2:1-1.5:1-1.5:0:5-3。2 . The preparation method according to claim 1 , wherein the molar ratio between the lithium source, phosphorus source, iron source and carbon source described in step (1) is 0.8-1.2:1-1.5:1- 1.5:0:5-3. 3.根据权利要求1所述的制备方法,其特征在于:步骤(1)所述的锂源为氢氧化锂、碳酸锂、磷酸氢锂中的一种。3 . The preparation method according to claim 1 , wherein the lithium source in step (1) is one of lithium hydroxide, lithium carbonate and lithium hydrogen phosphate. 4 . 4.根据权利要求1所述的制备方法,其特征在于:步骤(1)所述的磷源为磷酸氢二铵、磷酸一氢铵、磷酸中的一种。4 . The preparation method according to claim 1 , wherein the phosphorus source in step (1) is one of diammonium hydrogen phosphate, ammonium monohydrogen phosphate and phosphoric acid. 5 . 5.根据权利要求1所述的制备方法,其特征在于:步骤(1)所述的铁源为硫酸亚铁、磷酸铁、氧化铁、氯化铁、乙酸铁中的一种。5 . The preparation method according to claim 1 , wherein the iron source in step (1) is one of ferrous sulfate, ferric phosphate, ferric oxide, ferric chloride, and ferric acetate. 6 . 6.根据权利要求1所述的制备方法,其特征在于:步骤(1)所述的碳源为葡萄糖、果糖、蔗糖中的一种。6 . The preparation method according to claim 1 , wherein the carbon source in step (1) is one of glucose, fructose and sucrose. 7 . 7.根据权利要求1所述的制备方法,其特征在于:步骤(1)所述的分散液的分散方式为大功率超声分散,功率为800W-1000W。7 . The preparation method according to claim 1 , wherein the dispersion method of the dispersion liquid in step (1) is high-power ultrasonic dispersion, and the power is 800W-1000W. 8 . 8.根据权利要求1所述的制备方法,其特征在于:步骤(3)所述的水浴加热温度为80-100 ℃。8 . The preparation method according to claim 1 , wherein the heating temperature of the water bath in step (3) is 80-100° C. 9 . 9.根据权利要求1所述的制备方法,其特征在于:步骤(4)所述煅烧过程分为两段,第一段在600℃保温3-5h,第二段在700-900℃保温3-5h,升温速率为3-5℃/min。9 . The preparation method according to claim 1 , wherein the calcination process of step (4) is divided into two stages, the first stage is kept at 600°C for 3-5 hours, and the second stage is kept at 700-900°C for 3 hours. 10 . -5h, the heating rate is 3-5°C/min.
CN201911048791.4A 2019-10-31 2019-10-31 Preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery Active CN110723718B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911048791.4A CN110723718B (en) 2019-10-31 2019-10-31 Preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911048791.4A CN110723718B (en) 2019-10-31 2019-10-31 Preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery

Publications (2)

Publication Number Publication Date
CN110723718A true CN110723718A (en) 2020-01-24
CN110723718B CN110723718B (en) 2022-09-06

Family

ID=69222645

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911048791.4A Active CN110723718B (en) 2019-10-31 2019-10-31 Preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery

Country Status (1)

Country Link
CN (1) CN110723718B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113072052A (en) * 2021-03-29 2021-07-06 山东大学 Waste lithium iron phosphate lithium supplement repair method and application
CN114122406A (en) * 2022-01-25 2022-03-01 成都特隆美储能技术有限公司 Preparation method of graphene modified lithium iron phosphate and lithium iron phosphate

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20120021183A (en) * 2010-08-31 2012-03-08 삼성에스디아이 주식회사 Cathode active material, preparation method thereof, and cathode and lithium battery containing the material
CN103441268A (en) * 2013-07-09 2013-12-11 国家纳米科学中心 Carbon-coated lithium ion battery positive electrode material lithium iron phosphate and preparation method thereof
CN105514366A (en) * 2015-12-04 2016-04-20 齐鲁工业大学 Preparation method of nitrogen-doped graphene composite LiFePO4 lithium ion battery cathode material
CN106252635A (en) * 2016-09-30 2016-12-21 合肥国轩高科动力能源有限公司 Graphene-coated lithium iron phosphate cathode material and preparation method thereof
CN107068990A (en) * 2016-12-26 2017-08-18 苏州高通新材料科技有限公司 Graphene composite lithium iron phosphate cathode material and preparation method and application

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20120021183A (en) * 2010-08-31 2012-03-08 삼성에스디아이 주식회사 Cathode active material, preparation method thereof, and cathode and lithium battery containing the material
CN103441268A (en) * 2013-07-09 2013-12-11 国家纳米科学中心 Carbon-coated lithium ion battery positive electrode material lithium iron phosphate and preparation method thereof
CN105514366A (en) * 2015-12-04 2016-04-20 齐鲁工业大学 Preparation method of nitrogen-doped graphene composite LiFePO4 lithium ion battery cathode material
CN106252635A (en) * 2016-09-30 2016-12-21 合肥国轩高科动力能源有限公司 Graphene-coated lithium iron phosphate cathode material and preparation method thereof
CN107068990A (en) * 2016-12-26 2017-08-18 苏州高通新材料科技有限公司 Graphene composite lithium iron phosphate cathode material and preparation method and application

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
常龙娇 等: "《锂离子电池磷酸盐系材料》", 30 September 2019, 冶金工业出版社 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113072052A (en) * 2021-03-29 2021-07-06 山东大学 Waste lithium iron phosphate lithium supplement repair method and application
CN113072052B (en) * 2021-03-29 2022-06-28 山东大学 A kind of waste lithium iron phosphate supplementary lithium repair method and application
CN114122406A (en) * 2022-01-25 2022-03-01 成都特隆美储能技术有限公司 Preparation method of graphene modified lithium iron phosphate and lithium iron phosphate

Also Published As

Publication number Publication date
CN110723718B (en) 2022-09-06

Similar Documents

Publication Publication Date Title
CN105161705B (en) A kind of lithium manganese phosphate cladding nickel-cobalt lithium manganate cathode material and preparation method thereof
CN106058202A (en) Carbon-coated metal ion-doped sodium vanadium phosphate composite cathode material prepared by freeze drying method, as well as preparation method and application thereof
CN113526483B (en) Ferro-phosphorus sodalite type cathode material and preparation method and application thereof
CN108376767A (en) A kind of red phosphorus/nitrogen-doped graphene composite negative pole material and its preparation method and application
CN101222044A (en) Novel conductive agent doped/coated lithium iron phosphate material and preparation method
CN105514366B (en) A kind of preparation method of the compound LiFePO4 anode material for lithium-ion batteries of nitrogen-doped graphene
CN102148371A (en) Graphene/phosphoric acid iron-lithium composite material with sandwich structure and preparation method thereof
CN107845801B (en) A kind of synergistically modified lithium cobalt fluorophosphate cathode material and preparation method thereof
CN103227324A (en) Preparation method of iron oxide cathode material for lithium ion battery
CN108963235A (en) Graphene enhances carbon coating titanium phosphate manganese sodium micron ball electrode material and its preparation method and application
CN111244465A (en) Preparation of a nitrogen-doped metal carbide material
CN110723718B (en) Preparation method of nitrogen-doped graphene/lithium iron phosphate composite material for lithium ion battery
CN106099092A (en) A kind of preparation method of the copper vanadate for lithium ion battery negative material
CN104393275A (en) Preparation method of carbon-coated lithium titanate battery material
CN117525549A (en) Carbon-coated mixed phosphate positive electrode material, and preparation method and application thereof
CN110980720B (en) Nitrogen-doped graphite material and preparation method and application thereof
CN103693632B (en) A kind of preparation method of lithium vanadyl phosphate positive material for lithium ion battery
WO2019127031A1 (en) Energy composite material for lithium battery and preparation method therefor
CN114388738B (en) Silicon-based anode material and preparation method and application thereof
CN108461740A (en) A kind of LiVOPO4Nickelic tertiary cathode material of lithium ion battery of cladding and its preparation method and application
CN114455563B (en) Modified lithium iron phosphate material and preparation method and application thereof
CN117088348A (en) A method of carbon coating modified lithium iron phosphate cathode
CN113816425B (en) MoS 2 Nitrogen-doped carbon/modified activated carbon sodium ion battery negative electrode material and preparation method thereof
CN116111071A (en) A modified porous lithium iron phosphate and its preparation method and application
CN110085809A (en) Graphene nano tape base composite ferric lithium phosphate material, preparation method and application

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant