CN102655233B - Preparation method of LiFePO4/C anode material of lithium ion battery - Google Patents
Preparation method of LiFePO4/C anode material of lithium ion battery Download PDFInfo
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- CN102655233B CN102655233B CN201110415550.6A CN201110415550A CN102655233B CN 102655233 B CN102655233 B CN 102655233B CN 201110415550 A CN201110415550 A CN 201110415550A CN 102655233 B CN102655233 B CN 102655233B
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Abstract
The invention relates to a preparation method of a LiFePO4/C anode material of a lithium ion battery. Phenolic resin which is generated by carrying out in-situ esterification on the surface of a FePO4 precursor is roasted at a high temperature and a cracked carbon membrane can well cover the surface of the LiFePO4/C anode material; and the composite anode material has the characteristics of high specific capacity, preferable circulation performance and the like. The preparation method disclosed by the invention has the advantages of simple process flow, cheap and easily-obtained raw materials, low production cost and high yield, and a potential of large-scale industrial production.
Description
Technical field
The present invention relates to a kind of lithium ion battery LiFePO
4the preparation method of/C positive electrode, belongs to battery production preparing technical field.
Background technology
Lithium ion battery has high energy density, high open circuit voltage, good security performance.So lithium ion battery has got more and more people's extensive concerning since coming out always.And in whole lithium-ion battery system, the performance of positive electrode is most important especially.In several positive electrodes of applying at present, LiFePO
4advantages such as have specific capacity larger, cycle performance is fabulous, and cost of material is low, environment-protecting asepsis and be suitable as very much lithium ion power battery cathode material, thereby receive increasing concern; But LiFePO
4positive electrode electronic conductivity is extremely low, and its Electrode behaviour is subject to diffusion control, how under room temperature and high current density condition, to improve LiFePO
4actual capacity be that researcher is making great efforts a difficult problem of capturing always.Research work in recent years mainly launches around following three aspects: (1) improves size and the pattern that synthetic method is controlled product particle; (2) at LiFePO
4particle surface coated with conductive material improves the conductive capability of composite material; (3) ion doping is to improve LiFePO
4electronic conductivity.Water soluble phenol resin has cheap, free from environmental pollution, nontoxic, nonflammable explosive, the advantage such as fail safe is high of preparation cost; After mixing with powdery granule, dipping property is very strong, can better be coated on powder particle surface, and it is curing and decomposition temperature is all lower, so water soluble phenol resin is a kind of good carbon source, and at LiFePO
4the bibliographical information of the coated water soluble phenol resin of precursor surface in situ esterification seldom.
Summary of the invention
The invention provides lithium ion battery LiFePO
4the preparation method of/C positive electrode, object is to overcome anode material for lithium-ion batteries LiFePO in prior art
4cost is high, the shortcoming of poor performance; The present invention has the feature of the higher and good cycle of low cost of manufacture, less energy consumption and capacity.
technical solution of the present invention is as follows:
(1) 0.04～0.08mol Fe source compound and 0.04～0.10mol P source compound are dissolved in the deionized water of 200～400ml, then add the coating material of 2～5g, control temperature at 45～75 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip alkaline matter, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 80～120 ℃ of dry 10～12h;
(3) under constantly stirring, get 0.02～0.04mol step (2) gained FePO
4precursor joins in the deionized water of 50～100ml, in temperature-rise period, 0.3～0.5g coating material, 0.33～0.6g phenols and 0.6～1.2g aldehyde material are added successively, when temperature approaches 75～95 ℃, Li source compound is added, lucifuge, controls temperature at 75～95 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, by step (3) gained mixture, after 600～800 ℃ of calcining 10～24h, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
Wherein, above-mentioned Fe source compound used is ferric nitrate or iron chloride, and Li source compound is phosphoric acid, ammonium phosphate or ammonium dihydrogen phosphate, and Li source compound is lithium hydroxide, lithium carbonate or lithium nitrate; Aldehydes matter is resorcinol, phenol or cresols; Aldehyde material is formaldehyde, acetaldehyde or benzaldehyde; Coating material is PEG, PVP or CTAB; Being used for regulating the alkaloids of pH value is sodium hydroxide solution, urea liquid or ammoniacal liquor, above-mentioned Li source compound used and FePO
4the mol ratio of precursor is 0.95～1.02:1, and above-mentioned inert protective gas is nitrogen or argon gas.
the present invention has following beneficial effect:
At FePO
4the phenolic resins that the esterification of precursor surface in situ generates, after high-temperature calcination, the carbon film of cracking can well be coated on LiFePO
4the features such as positive electrode is surperficial, and this kind of composite positive pole has higher specific capacity, good cycle performance.Technological process of the present invention is simple, and raw material is cheap and easy to get, and production cost is low, and productive rate is higher, has the potential of large-scale industrial production.
Accompanying drawing explanation
Fig. 1 is the positive electrode LiFePO of embodiment 1 preparation
4the XRD spectra of/C;
Fig. 2 is the positive electrode LiFePO of embodiment 1 preparation
4the TEM spectrogram of/C;
Fig. 3 is the positive electrode LiFePO of embodiment 1 preparation
4the chemical property spectrogram of/C under different multiplying.
Embodiment
For clearer explanation the present invention, enumerate following instance, but its to the present invention without any restriction.
embodiment 1
(1) 0.04mol ferric nitrate and 0.05mol phosphoric acid are dissolved in the deionized water of 200ml, then add the PEG of 5g, control temperature at 60 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip ammoniacal liquor, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 120 ℃ of dry 10h;
(3) take the FePO of 0.02mol step (2) gained
4precursor, join in 50ml deionized water, constantly stir, in temperature-rise period, 0.3gCTAB, 0.33g resorcinol and 0.6g formaldehyde are added successively, when temperature approaches 85 ℃, by the proportioning of Fe and Li mol ratio 1:1, lithium hydroxide is added, lucifuge, controls temperature at 85 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after the resulting mixture of step (3) is calcined to 12h at 700 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 2
(1) 0.04mol ferric nitrate and 0.05mol ammonium phosphate are dissolved in the deionized water of 150ml, then add the CTAB of 3g, control temperature at 45 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip urea liquid, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 80 ℃ of dry 12h;
(3) take 0.02mol step (2) gained FePO
4precursor, join in 50ml deionized water, constantly stir, in temperature-rise period, 0.3gPEG, 0.33g cresols and 0.6g formaldehyde are added successively, when temperature approaches 75 ℃, by the proportioning of Fe and Li mol ratio 1:0.95, lithium carbonate is added, lucifuge, controls temperature at 75 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after the resulting mixture of step (3) is calcined to 16h at 800 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 3
(1) 0.05mol iron chloride and 0.07mol phosphoric acid are dissolved in the deionized water of 250ml, then add the CTAB of 4g, control temperature at 55 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip sodium hydroxide solution, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 100 ℃ of dry 12h;
(3) take 0.03mol step (2) gained FePO
4precursor, join in 50ml deionized water, constantly stir, in temperature-rise period, 0.4gPVP, 0.495g phenol and 0.9g benzaldehyde are added successively, when temperature approaches 80 ℃, by the proportioning of Fe and Li mol ratio 1:0.98, lithium nitrate is added, lucifuge, controls temperature at 80 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after the resulting mixture of step (3) is calcined to 20h at 750 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 4
(1) 0.05mol iron chloride and 0.07mol ammonium dihydrogen phosphate are dissolved in the deionized water of 400ml, then add the PEG of 5g, control temperature at 70 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip ammoniacal liquor, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 90 ℃ of dry 12h;
(3) take 0.03mol step (2) gained FePO
4precursor, join in 50ml deionized water, constantly stir, in temperature-rise period, 0.4gPVP, 0.66g resorcinol and 1.2g benzaldehyde are added successively, when temperature approaches 90 ℃, by the proportioning of Fe and Li mol ratio 1:1.02, lithium carbonate is added, lucifuge, controls temperature at 90 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after the resulting mixture of step (3) is calcined to 24h at 650 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 5
(1) 0.06mol iron chloride and 0.09mol ammonium dihydrogen phosphate are dissolved in the deionized water of 300ml, then add the PVP of 2g, control temperature at 65 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip urea liquid, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 100 ℃ of dry 12h;
(3) take 0.05mol step (2) gained FePO
4precursor, join in 70ml deionized water, constantly stir, in temperature-rise period, 0.4gCTAB, 0.66g resorcinol and 1.2g acetaldehyde are added successively, when temperature approaches 95 ℃, by the proportioning of Fe and Li mol ratio 1:1, lithium hydroxide is added, lucifuge, controls temperature at 95 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after the resulting mixture of step (3) is calcined to 20h at 700 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 6
(1) 0.04mol ferric nitrate and 0.05mol phosphoric acid are dissolved in the deionized water of 400ml, then add the PEG of 5g, control temperature at 50 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip sodium hydroxide solution, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 120 ℃ of dry 8h;
(3) take 0.02mol step (2) gained FePO
4precursor, join in 50ml deionized water, constantly stir, in temperature-rise period, 0.3gPVP, 0.33g cresols and 0.6g acetaldehyde are added successively, when temperature approaches 80 ℃, by the proportioning of Fe and Li mol ratio 1:0.98, lithium nitrate is added, lucifuge, controls temperature at 80 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after resulting mixture is calcined to 24h at 600 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 7
(1) 0.05mol ferric nitrate and 0.07mol ammonium phosphate are dissolved in the deionized water of 350ml, then add the CTAB of 3g, control temperature at 75 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip urea liquid, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 90 ℃ of dry 10h;
(3) take 0.03mol step (2) gained FePO
4precursor, join in 70ml deionized water, constantly stir, in temperature-rise period, 0.4gPEG, 0.495g resorcinol and 0.9g formaldehyde are added successively, when temperature approaches 85 ℃, by the proportioning of Fe and Li mol ratio 1:1, lithium hydroxide is added, lucifuge, controls temperature at 85 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after resulting mixture is calcined to 16h at 750 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
embodiment 8
(1) 0.06mol iron chloride and 0.09mol ammonium dihydrogen phosphate are dissolved in the deionized water of 200ml, then add the PEG of 2g, control temperature at 65 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip ammoniacal liquor, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 100 ℃ of dry 12h;
(3) take 0.05mol step (2) gained FePO
4precursor, join in 70ml deionized water, constantly stir, in temperature-rise period, 0.4gPVP, 0.66g phenyl methylcarbamate and 1.2g formaldehyde are added successively, when temperature approaches 90 ℃, by the proportioning of Fe and Li mol ratio 1:1.02, lithium carbonate is added, lucifuge, controls temperature at 90 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, after the resulting mixture of step (3) is calcined to 20h at 700 ℃, cool to room temperature grinds, and can obtain lithium ion battery LiFePO
4/ C positive electrode.
Claims (1)
1. prepare anode material for lithium-ion batteries LiFePO for one kind
4the method of/C, comprises the steps:
(1) 0.04～0.08mol Fe source compound and 0.04～0.10mol P source compound are dissolved in the deionized water of 200～400ml, then add the coating material of 2～5g, control temperature at 45～75 ℃, strong agitation;
(2) in above-mentioned mixed liquor, slowly drip alkaline matter, be adjusted to pH value 2～3, occur FePO completely
4after white precipitate, by the FePO obtaining
4precursor fully washs, and then vacuumizes 80～120 ℃ of dry 10～12h;
(3) under constantly stirring, get 0.02～0.04mol step (2) gained FePO
4precursor joins in the deionized water of 50～100ml, in temperature-rise period, 0.3～0.5g coating material, 0.33～0.6g phenols and 0.6～1.2g aldehyde material are added successively, when temperature is 75～95 ℃, Li source compound is added, lucifuge, controls temperature at 75～95 ℃ again, strong agitation, until by deionized water evaporate to dryness;
(4), under inert atmosphere protection, by step (3) gained mixture, after 600～800 ℃ of calcining 10～24h, cool to room temperature grinds, and obtains lithium ion battery LiFePO
4/ C positive electrode;
The described Fe source compound of step (1) is ferric nitrate or iron chloride, and described P source compound is phosphoric acid, ammonium phosphate or ammonium dihydrogen phosphate;
Described in step (2), being used for regulating the alkaloids of pH value is sodium hydroxide solution, urea liquid or ammoniacal liquor;
The described coating material in step (1) and (3) is polyethylene glycol, polyvinylpyrrolidone or softex kw;
The described aldehydes matter of step (3) is resorcinol, phenol or cresols; Aldehyde material is formaldehyde, acetaldehyde or benzaldehyde; Li source compound is lithium hydroxide, lithium carbonate or lithium nitrate; Li source compound and FePO
4the mol ratio of precursor is 0.95～1.02:1.
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| CN103985876B (en) * | 2014-05-15 | 2017-02-22 | 中国科学院化学研究所 | Method for performing in-situ controllable coating on lithium ion battery electrode material by phenolic resin |
| CN104157873A (en) * | 2014-08-04 | 2014-11-19 | 北京万源工业有限公司 | Method for preparing modified lithium iron phosphate by using polymerization reaction |
| CN106558696A (en) * | 2015-09-28 | 2017-04-05 | 郑州比克电池有限公司 | A kind of lithium ion battery LiFePO4Positive electrode and preparation method thereof |
| CN106654264A (en) * | 2017-01-12 | 2017-05-10 | 吉林大学 | Solvothermal assisted preparation method of LiFePO4/C multistage composite microspheres |
| CN106654219A (en) * | 2017-01-12 | 2017-05-10 | 吉林大学 | Ion exchange assisted preparation method of LiFePO4/C nano composite material |
| CN110416541A (en) * | 2019-07-12 | 2019-11-05 | 大连恒超锂业科技有限公司 | A kind of preparation method of the modified phosphate iron lithium of morphology controllable |
| CN112436132B (en) * | 2020-12-10 | 2021-07-02 | 桂林理工大学 | Method for preparing in-situ carbon-coated porous ferric phosphate material by adopting sweet osmanthus |
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| CN101937987A (en) * | 2010-07-30 | 2011-01-05 | 合肥工业大学 | Method for preparing composite anode material LiFePO4/C for lithium ion battery |
| CN102034964A (en) * | 2009-09-24 | 2011-04-27 | 复旦大学 | Method for preparing lithium ion battery composite material |
| CN102110811A (en) * | 2011-01-14 | 2011-06-29 | 浙江大学 | Method for preparing nanoscale lithium ion battery LiFePo4/C anodal material |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102034964A (en) * | 2009-09-24 | 2011-04-27 | 复旦大学 | Method for preparing lithium ion battery composite material |
| CN101937987A (en) * | 2010-07-30 | 2011-01-05 | 合肥工业大学 | Method for preparing composite anode material LiFePO4/C for lithium ion battery |
| CN102110811A (en) * | 2011-01-14 | 2011-06-29 | 浙江大学 | Method for preparing nanoscale lithium ion battery LiFePo4/C anodal material |
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