CN106315537A - Preparation method of lithium iron phosphate powder - Google Patents

Preparation method of lithium iron phosphate powder Download PDF

Info

Publication number
CN106315537A
CN106315537A CN201610634396.4A CN201610634396A CN106315537A CN 106315537 A CN106315537 A CN 106315537A CN 201610634396 A CN201610634396 A CN 201610634396A CN 106315537 A CN106315537 A CN 106315537A
Authority
CN
China
Prior art keywords
powder
preparation
glass
lifepo
feo
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
CN201610634396.4A
Other languages
Chinese (zh)
Inventor
郭宏伟
宋建波
宁峰明
罗亚丽
艾志远
杨晨
杨龙康
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.)
Shaanxi University of Science and Technology
Original Assignee
Shaanxi University of Science and Technology
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 Shaanxi University of Science and Technology filed Critical Shaanxi University of Science and Technology
Priority to CN201610634396.4A priority Critical patent/CN106315537A/en
Publication of CN106315537A publication Critical patent/CN106315537A/en
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
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention provides a preparation method of lithium iron phosphate. The preparation method comprises the steps of 1 preparation of Li2O-P2O5 binary glass, 2 preparation of Li2O-FeO-P2O5 ternary matrix glass-ceramics and 3 preparation of LiFePO4 powder. By preparing the conductive lithium iron phosphate powder through a two-time high-temperature melting casting method, the defects that lithium iron phosphate produced through other technologies is poor in conductivity and high in industrialization difficulty are overcome. The lithium iron phosphate powder obtained through the preparation method is excellent in conductivity, uniform in particle size distribution and high in crystal purity and can be used as an excellent lithium ion battery material.

Description

A kind of preparation method of LiFePO 4 powder
Technical field
The present invention relates to the manufacture method of a kind of LiFePO4, particularly to a kind of LiFePO4 powder with conducting function The preparation method of body.
Background technology
LiFePO4 have have extended cycle life, heat stability is high and the many merits such as environment-protecting asepsis, be expected to become of future generation The preferable positive electrode of lithium ion battery especially electrokinetic cell, but it is at safety, cost, specific energy also needs to new Break through.
Tang's cause is remote etc. (Tang Zhiyuan, soars, Xue Jianjun etc. anode material for lithium-ion batteries LiFePO4Preparation and electrochemistry Performance study [J]. University Of Tianjin's journal, 2007,40 (4): 468-472.) by by methyllanthionine ferrum Fe (NH4)2(SO4)2·6H2O With ammonium dihydrogen phosphate (NH4H2PO4) 1:1 mixing in molar ratio, it is dissolved in deionized water, is subsequently adding H2O2, anti-at 95 DEG C FePO should be prepared4Precursor, then with Li2CO3Mixing, calcines 12 hours in 600 DEG C, cools down, grinds to obtain end product LiFePO4.The method process is simple, process conditions are easy to control and easily realizes industrialization, but its product grain size is uneven, grain Footpath is distributed more widely, crystal shape is irregular, the production cycle is long.
Qu Tao etc. (Qu Tao, Tian Yanwen, clock ginseng cloud etc. carbon dope prepares anode material for lithium-ion batteries LiFePO4[J]. material Leader, 2007,21 (4): 37-41.) use Solid phase synthesis LiFePO4LiFePO with carbon dope4, and have studied carbon dope amount not With to LiFePO4The impact of the electrical property of material.Result shows: along with the increase of carbon dope amount, the initial discharge of gained sample is held Amount increases, and when phosphorus content is 8.5%, LiFePO4Positive electrode has the first discharge specific capacity of maximum
Li Faxi etc. (Li Faxi, Chou Weihua, Hu Huanyu etc. microwave synthesis anode material of lithium battery LiFePO4Electrochemistry Energy [J]. study and design, 2005,29 (6): 346-348.) use Li2CO3、FeC2O4·2H2O and NH4H2PO4For raw material, use Acetone disperses, ball milling, briquetting, puts into the crucible with cover equipped with activated carbon, uses household microwave oven heating to obtain LiFePO4Sample Product.The method experimental implementation is simple, synthesis cycle is shorter, but it is not suitable for industrialized mass.
Zhang Junling (Zhang Junling. the morphology control [J] of Hydrothermal Synthesis LiFePO 4 powder. New Chemical Materials, 2008,36 (6): 74-75.) at N2Under protection, by H3PO4With Fe SO4Solution moves in autoclave and stirs, and adds Li at a set temperature OH, sealing autoclave, reacts 4h at 180 DEG C.Then gained sample is dried at 120 DEG C 2h, prepares through 600 DEG C of calcining 2h LiFePO4Material.The method operating procedure is simple, product grain granularity is little, thing is mutually single, uniform, but it may be only available for system Standby a small amount of powder body, and it is unfavorable for industrialization large-scale production.
(Wang Rui, the Yang Duan peak .LiFePO such as Wang Rui4Preparation and chemical property [J]. Chemical Engineer, 2009,165 (6): 24-26.) using citric acid, ethylenediaminetetraacetic acid (EDTA) and oxalic acid is that chelating agent uses sol-gel process to prepare phosphoric acid Ferrum lithium material.First stirring soluble in water for chelating agent is added Fe (NO3)3·9H2O dissolves, and dissolves in LiOH H the most successively2O And NH4H2PO4, regulation pH value is 8.5-9.5, evaporates solvent and obtains gel, be dried to obtain powdery precursor, then exist at 60-80 DEG C The lower heat treatment of nitrogen protection, cools down to obtain LiFePO 4 material.Its product has that grain diameter is little, narrow diameter distribution, easily controllable, Powder sintering performance is good, chemical uniformity is good, heat treatment temperature is low, equipment simple operation and other advantages, but dry shrinkage is bigger, Synthesis cycle length, preparation process are complicated, be not easy to industrialization large-scale production.
Yang Rong etc. (Yang Rong, Zhao Mingshu, Du Baozhong etc. coprecipitation prepares positive electrode Li Fe PO4Research [J]. dilute There are metal material and an engineering, 2007,36 (2): 631-634.) by (NH4)2Fe(SO4)2(NH4)2HPO4Solution mixes, and adds Appropriate ascorbic acid and a certain amount of LiOH solution, regulate pH value with ammonia, stirs 4-6h, then obtains iron phosphate through sucking filtration Lithium precursor, calcines it 12h under 550 DEG C of argon gas atmosphere, obtains LiFePO4 sample.Performance can be prepared by same method More excellent mixes Co2+LiFePO 4 material.This preparation process is simple, precursor synthesis temperature is low, the big rule that are prone to industrialization Mould produces, but its raw material is difficult to obtain, to have reacted difficulty, reaction time long.
Chen Zhao bravely waits (Chen Zhaoyong, Zhu Huali .LiFePO4The preparation of/C composite and performance study [J]. Changsha science and engineering College journal, 2007,4 (2): 84-88.) use sol-gel process to be prepared for LiFePO4/ C composite, and respectively with acetylene Black, sucrose and glucose are carbon source, record they first discharge specific capacity under 0.1C multiplying power be respectively 120,135,162m Ah/g, the Li Fe PO wherein made with glucose for carbon source4/ C composite has the most excellent high rate during charging-discharging, Under under 1C and 3C high magnification, first discharge specific capacity is respectively 0.1C multiplying power the 90% and 80% of specific discharge capacity.
Tan Xianyan etc. (Tan Xianyan, Hu Guorong, high rising sun light etc. the LiFePO of doping Mg4Electrochemical Properties [J]. electricity Pond, 2004,34 (5): 344-345.) prepare doping Mg2+LiFePO4The chemical property of material.Result shows: doping Mg2+After LiFePO4 crystal structure do not change, but with without Mg2+LiFePO4Material compare have more excellent Chemical property.Doping conductive materials or high volence metal ion can improve the specific discharge capacity of lithium iron phosphate positive material, But this is with expendable material volume as cost, hinder the progress of miniaturization of lithium ion battery to a certain extent.
(KeitaH, Tsuyoshi H, Yasuhiko B, the et al.Glass-ceramics with such as KeitaH LiFePO4crystals and crystal line tterning in glass by YAG aser rradition[J] .Solid State Ionics, 2007,178 (11-12): 801-807.) first by Li2CO3、FeC2O4·2H2O、Nb2O5With NH4H2PO4Mix Deng raw material, be heated to 300 DEG C of insulation 10h under nitrogen protection, then found at 1200 DEG C and obtain 26Li2O-43Fe O-5Nb2O5-26P2O5(mole percent) glass, finally by two kinds of different techniques to lithium iron phosphate glass Carrying out Crystallizing treatment, a kind of is traditional heat treating process, a kind of be use YAG laser wavelength be 1064nm Continuous print radiated wave makes lithium iron phosphate glass Surface Crystallization.Obtain two kinds of method gained samples through XRD analysis and the most only separate out LiFePO4 Crystal, but also need to improve LiFePO4The electrical conductivity of glass.
(Jozwiak P, Garbarczyk J E, Gendron F, the et al.Disorder in such as Jozwiak P LixFePO4:From glasses to nanocrystallites[J].Journal of Non-Crystalline Solids, 2008,354 (17): 1915-1925.) by Li2CO3(LiOH·H2O)、H4)2HPO4(NH4H2PO4)、Fe2O3Deng raw material Mix homogeneously, at 1270 DEG C, melted 1h obtains LixFe PO4(x=0 1) glass, is then carried out gained glass at 450 DEG C It is LiFePO that heat treatment obtains principal crystalline phase4And FePO4Crystallized glass.
(Lee S B, Cho S H, Cho S J, the et al.Synthesis of LiFePO4Material such as Lee S B with Improved Cycling Performance Under Harsh Conditions[J].Electrochemistry Communications, 2008,10:1219-1221.) divalent iron salt LiOH and H of dissolubility3PO4Use at 120 DEG C for raw material Hydro-thermal method has synthesized LiFePO in the short time4, XRD analysis and oxidation-reduction titration results show, synthesized material is single LiFePO4Phase, mean diameter is about 3 μm, and this material with the electric current density charge and discharge of 0.14m A cm-2, gram capacitance is 100mAh·g-1.The method uses Lithium hydrate (Li OH) to make precipitant needs the LiOH of many consumption 200%, adds raw material Cost.
In recent years, along with the further research and development to LiFePO4 application aspect, find that LiFePO4 becomes at raw material This, preparation technology, preparation time, volume, density, the aspect such as electrical conductivity, its process is complicated, and electrical conductivity is extremely low, and lithium ion spreads The slower shortcoming of coefficient makes it be difficult to industrialization large-scale production, how to prepare low cost, easy to operate, environmental protection, greatly It is problem demanding prompt solution during LiFePO4 produces that technical scale metaplasia is produced.
Summary of the invention
It is an object of the invention to the shortcoming overcoming above-mentioned prior art, it is provided that a kind of cost of material is low, preparation technology Simply, in raw material, phosphorus content is stable, and electrical property is excellent, easy to operate, environment-protecting asepsis, is suitable to the conduction iron phosphate produced in enormous quantities Powder for lithium preparation method, the LiFePO4 electric conductivity prepared according to the inventive method is excellent, and powder diameter is uniform, crystal purity Height, impurity content is small, can be as the heavy-duty battery material of big energy density.
For reaching above-mentioned purpose, the technical solution used in the present invention is:
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 850～900 DEG C, found 30～60min；
3) then, use platinum stirring paddle that melted glass melt is stirred 10～30min, then 850～900 DEG C of insulations 10～20min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 1-3mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, to obtain final product Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) then, add in batch Glass Batch Quality 0.1～0.01% iron filings after cross 50 mesh standard sieves and must mix Uniform batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 950～1050 DEG C, found 30～ 60min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 1-3mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 10～the glucose of 25% and 75～the Li of 90%2O-FeO-P2O5Ternary system Parent devitrified glass powder mixes to obtain mixture, then is added thereto to mixture quality 10～the deionized water of 30%, then by it Put into ball milling 15～30min in ball mill；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, in being passed through the atmosphere furnace of hydrogen and nitrogen, with 5～10 DEG C/heating rate of min, it is warming up to 750～850 DEG C, is incubated 2～4h, then the cooldown rate with 10～20 DEG C/min, from 750 ～850 DEG C be cooled to less than 40 DEG C LiFePO 4 powder.
Described Li2O is introduced by analytically pure lithium carbonate；Described P2O5By analytically pure phosphorus pentoxide, or (NH4)2HPO4Or (NH4)H2PO4Introduce；Described FeO is introduced by analytically pure ferrous oxide；Described iron powder is by analytically pure Iron filings introduce；Described glucose is introduced by analytically pure glucose；Described hydrogen and the ratio of nitrogen are 5:95.
The present invention utilizes the LiFePO 4 powder of the method preparation conduction of secondary high-temperature founding, compensate for other technique and produces LiFePO4 electric conductivity poor, shortcoming that industrialization difficulty is big.The LiFePO 4 powder obtained according to preparation method of the present invention Excellent conductivity, powder granule even size distribution, crystal purity is high, can use as excellent lithium ion battery material.
Accompanying drawing explanation
Fig. 1 is that the diffraction that the LiFePO 4 powder prepared according to the preparation method of the present invention detects at X-ray diffractometer shines Sheet, wherein abscissa is the angle of diffraction 2 θ/(°), and vertical coordinate is diffracted intensity.
Detailed description of the invention
Embodiment 1
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 850 DEG C, found 40min；
3) then, use platinum stirring paddle that melted glass melt stirs 20min, then be incubated 13min at 850 DEG C；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 1.6mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, to obtain final product Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) cross 50 mesh standard sieves after then, adding the iron filings of Glass Batch Quality 0.03% in batch and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 1000 DEG C, found 55min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 2.4mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 13% glucose and the Li of 87%2O-FeO-P2O5Ternary system parent crystallite Glass powder mixes to obtain mixture, then is added thereto to the deionized water of mixture quality 21%, then puts it in ball mill Ball milling 20min；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, is being passed through the gas that volume ratio is 5:95 of hydrogen and nitrogen In atmosphere stove, with the heating rate of 8 DEG C/min, it is warming up to 850 DEG C, is incubated 3h, then the cooldown rate with 12 DEG C/min, from 850 DEG C It is cooled to less than 40 DEG C and obtains LiFePO 4 powder.
See accompanying drawing 1, it can be seen that prepared crystal is the LiFePO that purity is higher4Crystal.
Embodiment 2
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 870 DEG C, found 50min；
3) then, use platinum stirring paddle that melted glass melt stirs 15min, then be incubated 19min at 870 DEG C；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 3mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, both obtained Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) cross 50 mesh standard sieves after then, adding the iron filings of Glass Batch Quality 0.07% in batch and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 1040 DEG C, found 35min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 1.6mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 21% glucose and the Li of 79%2O-FeO-P2O5Ternary system parent crystallite Glass powder mixes to obtain mixture, then is added thereto to the deionized water of mixture quality 16%, then puts it in ball mill Ball milling 15min；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, is being passed through the gas that volume ratio is 5:95 of hydrogen and nitrogen In atmosphere stove, with the heating rate of 6 DEG C/min, it is warming up to 780 DEG C, is incubated 2.5h, then the cooldown rate with 15 DEG C/min, from 780 DEG C be cooled to less than 40 DEG C LiFePO 4 powder.
Embodiment 3
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 890 DEG C, found 30min；
3) then, use platinum stirring paddle that melted glass melt stirs 28min, then be incubated 20min at 890 DEG C；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 2.4mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, to obtain final product Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) cross 50 mesh standard sieves after then, adding the iron filings of Glass Batch Quality 0.05% in batch and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 980 DEG C, found 45min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 1.9mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 17% glucose and the Li of 83%2O-FeO-P2O5Ternary system parent crystallite Glass powder mixes to obtain mixture, then is added thereto to the deionized water of mixture quality 30%, then puts it in ball mill Ball milling 23min；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, is being passed through the gas that volume ratio is 5:95 of hydrogen and nitrogen In atmosphere stove, with the heating rate of 9 DEG C/min, it is warming up to 820 DEG C, is incubated 3.5h, then the cooldown rate with 10 DEG C/min, from 820 DEG C be cooled to less than 40 DEG C LiFePO 4 powder.
Embodiment 4
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 880 DEG C, found 35min；
3) then, use platinum stirring paddle that melted glass melt stirs 10min, then be incubated 17min at 880 DEG C；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 1mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, to obtain final product Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) cross 50 mesh standard sieves after then, adding the iron filings of Glass Batch Quality 0.01% in batch and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 1050 DEG C, found 50min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 3mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 25% glucose and the Li of 75%2O-FeO-P2O5Ternary system parent crystallite Glass powder mixes to obtain mixture, then is added thereto to the deionized water of mixture quality 10%, then puts it in ball mill Ball milling 30min；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, is being passed through the gas that volume ratio is 5:95 of hydrogen and nitrogen In atmosphere stove, with the heating rate of 10 DEG C/min, it is warming up to 800 DEG C, is incubated 2h, then the cooldown rate with 17 DEG C/min, from 800 DEG C It is cooled to less than 40 DEG C and obtains LiFePO 4 powder.
Embodiment 5
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 900 DEG C, found 55min；
3) then, use platinum stirring paddle that melted glass melt stirs 25min, then be incubated 15min at 900 DEG C；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 2.1mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, to obtain final product Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) cross 50 mesh standard sieves after then, adding the iron filings of Glass Batch Quality 0.1% in batch and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 1020 DEG C, found 60min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 1mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 19% glucose and the Li of 81%2O-FeO-P2O5Ternary system parent crystallite Glass powder mixes to obtain mixture, then is added thereto to the deionized water of mixture quality 24%, then puts it in ball mill Ball milling 17min；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, is being passed through the gas that volume ratio is 5:95 of hydrogen and nitrogen In atmosphere stove, with the heating rate of 7 DEG C/min, it is warming up to 760 DEG C, is incubated 3h, then the cooldown rate with 13 DEG C/min, from 760 DEG C It is cooled to less than 40 DEG C and obtains LiFePO 4 powder.
Embodiment 6
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mixing to the uniformity more than 98%, be uniformly mixed joins Close material；
2) secondly, batch is added in the platinum crucible being warming up to 860 DEG C, found 60min；
3) then, use platinum stirring paddle that melted glass melt stirs 30min, then be incubated 10min at 860 DEG C；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of a size of 1.9mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, to obtain final product Li2O-P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously Obtain batch；
2) cross 50 mesh standard sieves after then, adding the iron filings of Glass Batch Quality 0.09% in batch and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 950 DEG C, found 40min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through cooling rapidly Rolling becomes the Li of 2.1mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh End, obtains Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 10% glucose and the Li of 90%2O-FeO-P2O5Ternary system parent crystallite Glass powder mixes to obtain mixture, then is added thereto to the deionized water of mixture quality 19%, then puts it in ball mill Ball milling 26min；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, is being passed through the gas that volume ratio is 5:95 of hydrogen and nitrogen In atmosphere stove, with the heating rate of 5 DEG C/min, it is warming up to 750 DEG C, is incubated 4h, then the cooldown rate with 20 DEG C/min, from 750 DEG C It is cooled to less than 40 DEG C and obtains LiFePO 4 powder.
The Li of the present invention2O is introduced by analytically pure lithium carbonate；P2O5By analytically pure phosphorus pentoxide, (NH4)2HPO4Or (NH4)H2PO4Introduce；FeO is introduced by analytically pure ferrous oxide；Iron powder is introduced by analytically pure iron filings；Glucose is by analytical pure Glucose introduce.
The present invention utilizes the method for secondary high-temperature founding to prepare LiFePO4, compensate for the LiFePO4 that other technique produces Electric conductivity is poor, the shortcoming that industrialization difficulty is big.Add the performance of LiFePO4 and the capacitance of unit volume.Institute of the present invention The LiFePO4 of preparation may realize large-scale industrial production.LiFePO4 uniformity prepared by the present invention is good, and energy consumption is low, joint Can environmental protection.

Claims (7)

1. the preparation method of a LiFePO 4 powder, it is characterised in that:
The first step: Li2O-P2O5The preparation of binary system glass
1) first, by the mol ratio of 1:1 by Li2O and P2O5Mix to the uniformity more than 98%, the batch being uniformly mixed；
2) secondly, batch is added in the platinum crucible being warming up to 850～900 DEG C, found 30～60min；
3) then, use platinum stirring paddle to melted glass melt stirring 10～30min, then 850～900 DEG C of insulations 10～ 20min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through rapid cold rolling Become the Li of a size of 1-3mm2O-P2O5Binary system glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in ball grinder and become the powder of 50～80 mesh, obtain Li2O- P2O5Binary system glass powder；
Second step: Li2O-FeO-P2O5The preparation of ternary system parent devitrified glass
1) first, by FeO:Li2The mol ratio of O=2:1 is by FeO and Li2O-P2O5Binary system glass powder mix homogeneously must be joined Close material；
2) then, add in batch Glass Batch Quality 0.1～0.01% iron filings after cross 50 mesh standard sieves and obtain mix homogeneously Batch；
3) then, batch is joined in the corundum crucible with cover being warming up to 950～1050 DEG C, found 30～60min；
4) then, melted glass melt is toppled over rapidly on the milling train flowing into the double roller of band water cooling, through rapid cold rolling Become the Li of 1-3mm2O-FeO-P2O5Ternary system parent devitrified glass fragment；
5) last, after the glass fragment of rolling is collected, put into ball milling in polyurethane ball-milling pot and become the powder of 300～500 mesh, i.e. Obtain Li2O-FeO-P2O5Ternary system parent devitrified glass powder；
3rd step: LiFePO4The preparation of powder body
1) first, according to mass fraction by 10～the glucose of 25% and 75～the Li of 90%2O-FeO-P2O5Ternary system parent Devitrified glass powder mixes to obtain mixture, then is added thereto to mixture quality 10～the deionized water of 30%, then puts it into Ball milling 15～30min in ball mill；
2) then, mixture after ball milling is air-dried into powder；
3) last, dry powder is put in graphite crucible, in being passed through the atmosphere furnace of hydrogen and nitrogen, with 5～10 DEG C/ The heating rate of min, is warming up to 750～850 DEG C, is incubated 2～4h, then the cooldown rate with 10～20 DEG C/min, from 750～ 850 DEG C are cooled to less than 40 DEG C and obtain LiFePO 4 powder.
The preparation method of LiFePO 4 powder the most according to claim 1, it is characterised in that: described Li2O is by analytical pure Lithium carbonate introduce.
The preparation method of LiFePO 4 powder the most according to claim 1, it is characterised in that: described P2O5By analytical pure Phosphorus pentoxide, (NH4)2HPO4Or (NH4)H2PO4Introduce.
The preparation method of LiFePO 4 powder the most according to claim 1, it is characterised in that: described FeO is by analytical pure Ferrous oxide introduce.
The preparation method of LiFePO 4 powder the most according to claim 1, it is characterised in that: described iron powder is by analytical pure Iron filings introduce.
The preparation method of LiFePO 4 powder the most according to claim 1, it is characterised in that: described glucose is by analyzing Pure glucose introduces.
The preparation method of LiFePO 4 powder the most according to claim 1, it is characterised in that: described hydrogen and nitrogen Volume ratio is 5:95.
CN201610634396.4A 2016-08-04 2016-08-04 Preparation method of lithium iron phosphate powder Pending CN106315537A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610634396.4A CN106315537A (en) 2016-08-04 2016-08-04 Preparation method of lithium iron phosphate powder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610634396.4A CN106315537A (en) 2016-08-04 2016-08-04 Preparation method of lithium iron phosphate powder

Publications (1)

Publication Number Publication Date
CN106315537A true CN106315537A (en) 2017-01-11

Family

ID=57739589

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610634396.4A Pending CN106315537A (en) 2016-08-04 2016-08-04 Preparation method of lithium iron phosphate powder

Country Status (1)

Country Link
CN (1) CN106315537A (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1677718A (en) * 2004-03-30 2005-10-05 中国科学院物理研究所 Method for preparing phosphate positive-pole material of lithium-ion cell
US20090217513A1 (en) * 2008-02-29 2009-09-03 Byd Company Limited Composite compound with mixed crystalline structure
US20100062339A1 (en) * 2008-03-21 2010-03-11 Byd Company Limited Cathode materials for lithium batteries
CN101826618A (en) * 2010-05-14 2010-09-08 成都联禾化工医药有限责任公司 Method for preparing superfine and high-dispersibility lithium iron phosphate
CN101830453A (en) * 2010-05-27 2010-09-15 谢朝华 Secondary sintering synthesis method for lithium iron phosphate
CN102983328A (en) * 2012-11-23 2013-03-20 清华大学 Method for preparing nanocrystalline lithium iron phosphate anode material from ferrous powder
CN105609763A (en) * 2015-12-23 2016-05-25 郑春燕 Rare earth Y doped lithium iron phosphate electrode material and preparation method thereof

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1677718A (en) * 2004-03-30 2005-10-05 中国科学院物理研究所 Method for preparing phosphate positive-pole material of lithium-ion cell
US20090217513A1 (en) * 2008-02-29 2009-09-03 Byd Company Limited Composite compound with mixed crystalline structure
US20100062339A1 (en) * 2008-03-21 2010-03-11 Byd Company Limited Cathode materials for lithium batteries
CN101826618A (en) * 2010-05-14 2010-09-08 成都联禾化工医药有限责任公司 Method for preparing superfine and high-dispersibility lithium iron phosphate
CN101830453A (en) * 2010-05-27 2010-09-15 谢朝华 Secondary sintering synthesis method for lithium iron phosphate
CN102983328A (en) * 2012-11-23 2013-03-20 清华大学 Method for preparing nanocrystalline lithium iron phosphate anode material from ferrous powder
CN105609763A (en) * 2015-12-23 2016-05-25 郑春燕 Rare earth Y doped lithium iron phosphate electrode material and preparation method thereof

Similar Documents

Publication Publication Date Title
Alsamet et al. Synthesis and characterization of nano-sized LiFePO4 by using consecutive combination of sol-gel and hydrothermal methods
KR101097546B1 (en) Method for the preparation of a lithium phosphate compound with an olivine crystal structure
CN100511778C (en) Method for producing high performance lithium ion battery anode material LiFePO*/C
Ji et al. General synthesis and morphology control of LiMnPO4 nanocrystals via microwave-hydrothermal route
CN100567142C (en) The preparation method of lithium iron phosphate series composite oxides
CN102311109B (en) Method for preparing LiFePO4/C composite cathode material by continuous reaction
CN101393982A (en) Method for producing carbon coated nano stage lithium iron phosphate by precipitation
CN101591012B (en) Preparation method of lithium iron phosphate as cathode material of lithium ion battery
CN106384822A (en) Preparation method of amorphous battery-grade iron phosphate, lithium iron phosphate, battery positive electrode material and secondary battery
CN100491239C (en) Preparation method of lithium iron phosphate as lithium ion battery anode material and product thereof
CN102244246B (en) Preparation method of lithium iron phosphate/carbon composite material
CN100420075C (en) Method for preparing lithium ion battery anode material lithium ion phosphate
CN106602023A (en) Method for in-situ synthesis of graphite phase carbon nitride-copper oxide composite material
CN105742629A (en) In-situ preparation method of positive electrode material lithium iron phosphate/graphene compound for lithium-ion battery
CN102502562B (en) Preparation method of lithium iron phosphate, lithium ion battery and anode material and anode thereof
Yang et al. Crystal structure and electrochemical performance of Li3V2 (PO4) 3 synthesized by optimized microwave solid-state synthesis route
CN101944615B (en) Lithium-manganese phosphate anode material for lithium ion battery and preparation method thereof
CN100483809C (en) Method for producing ultra-fine LiFePO4/C of lithium ion battery anode material
CN102544494A (en) Preparation method of nano composite lithium iron phosphate cathode material
Yi Rheological phase reaction synthesis of Co-doped LiMn 2 O 4 octahedral particles
CN104409734A (en) Lithium iron phosphate battery positive material prepared by using microwave-assisted sol-gel method
CN108321390B (en) Three-dimensional flower-shaped single crystal lithium iron phosphate and preparation method thereof
CN102983332A (en) Preparation method for lithium iron phosphate material of positive electrode of lithium ion secondary battery
US12030788B2 (en) Process for solid synthesis of mixed metal oxides, and surface modification of said materials and use of said materials in batteries, in particular as cathode materials
CN102491303A (en) Method for preparing lithium ion phosphate, cathode material of lithium ion battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20170111

WD01 Invention patent application deemed withdrawn after publication