CN102306769B - Preparation method of lithium iron phosphate/lithium vanadium phosphate composite material - Google Patents
Preparation method of lithium iron phosphate/lithium vanadium phosphate composite material Download PDFInfo
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Abstract
The invention relates to a preparation method of a lithium iron phosphate/lithium vanadium phosphate composite material. The method comprises the following steps: mixing iron phosphate and vanadium pentoxide which are utilized as raw materials with a lithium salt compound; adding a chelating agent; grinding and mixing; performing heat treatment in an inert atmosphere, and then adding a carbon source material; and heating, roasting and cooling to room temperature to obtain the carbon-coated lithium iron phosphate/lithium vanadium phosphate composite material. The lithium iron phosphate/lithiumvanadium phosphate composite material can be assembled into a testing battery of which the discharge specific capacity can reach 144mAh/g with the current of 150mA/g at room temperature and can reach105mAh/g with the current of 30mA/g at the temperature of minus 20 DEG C, the crystal form is complete, the particle appearance is regular, and excellent normal-temperature and low-temperature electrochemical performances are shown. All the raw materials in the method are bulk industrial chemicals, the cost is low, the process route is simple, the industrial scale production is easy to realize and the application prospect is very broad.
Description
Technical field
The invention belongs to the electrochemical power source technical field of material.Particularly relate to a kind of method that adopts the auxiliary carbothermic method of oxalic acid chelating to prepare lithium ion anode composite material lithium iron phosphate/lithium vanadium phosphate.Has wide application prospect at secondary lithium battery commonly used and power source cell positive material field.
Background technology
The energy and environment are to enter two Tough questions that 21 century must face, and the reproducible new forms of energy of exploitation cleaning are one of material technical fields of tool in the World Economics from now on.A kind of as electrochemical energy, lithium ion battery have the operating voltage height, lightweight, specific energy is large, self discharge is little, have extended cycle life, memory-less effect, the advantage such as low in the pollution of the environment.
On the one hand, the startup of national electric motor car project, the update of electronic product, and the propelling of the modernization of national defense are for the development of lithium ion battery industry provides chance.On the other hand, the user is more and more higher to the quality requirements of battery.Be mainly reflected in high power capacity, high-rate charge-discharge capability, excellent cycle performance, good cryogenic property and economy etc.This has higher requirement for the development of lithium electricity industry at technological layer.
At present, positive electrode is the key factor of restriction lithium ion battery technological progress.The performance of positive electrode affects the performance of battery to a great extent, and is directly determining the height of battery cost.In a word, the problem of positive electrode has become the bottleneck problem of whole lithium electricity industry
Present stage, the positive electrode that lithium ion battery uses mainly is lithium transition-metal oxide, comprises the LiCoO of six side's layer structures
2, LiNiO
2And LiNi
1-x-yCoxMnyO
2(0≤x, y≤1, x+y≤1), the LiMn of spinel structure
2O
4And the LiFePO of polyanion class positive electrode such as olivine structural
4The Li of (LiFePO4), NASICON structure
3V
2(PO
4)
3LiCoO wherein
2Realized commercialization, but its selling at exorbitant prices, toxicity is larger, and the resource-constrained of cobalt; LiNiO
2Synthetic relatively difficulty; LiMn
2O
4Lower, the cycle life of capacity especially the cycle life under the high temperature is relatively poor.The LiFePO of olivine structural
4Although stability and fail safe are all better, high-rate charge-discharge capability and cryogenic property are not so good.The Li of NASICON structure
3V
2(PO
4)
3Better still charge and discharge platform is more for high rate capability and cryogenic property, and the oxide of vanadium is poisonous, and price is also higher.
Polyanion composite material xLiFePO
4YLi
3V
2(PO
4)
3(x, y represent respectively LiFePO in the composite material to/C
4, Li
3V
2(PO
4)
3Proportionality coefficient) compare with other materials as the positive electrode of lithium ion battery following advantage arranged: (1) desirable theoretical capacity (at 2.3-4.5V, LiFePO
4Theoretical capacity is 170mAh/g, Li
3V
2(PO
4)
3Theoretical capacity is 133mAh/g, xLiFePO
4YLi
3V
2(PO
4)
3The theoretical capacity of/C is 133-170mAh/g); (2) can suitably adjust as required xLiFePO
4YLi
3V
2(PO
4)
3LiFePO among the/C
4And Li
3V
2(PO
4)
3Ratio; (3) good reversibility of electrode reaction; (4) thermal stability and chemical stability are high, use safety; (5) cost of material is low.
At present the research of polyanion class positive electrode is mainly concentrated on the LiFePO4, many scholars have carried out the relevant research to it.For LiFePO
4Electronic conductivity is low (greatly about 10
-9S/cm) and the lithium ion diffusion coefficient little (about 1.8 * 10
-16-2.2 * 10
-14Cm
2/ s) shortcoming mainly is to coat and the approach of ion doping improves by carbon.Yet, fact proved, although these two kinds of methods can improve LiFePO to a certain extent
4Performance, but DeGrain, high power charging-discharging and the cryogenic property of LiFePO4 are not still solved at all.
The high temperature solid-state method that is adopted by vast researcher at present (A.Yamada et al.US Pat.5910382; CN1401559A) be with ferrous salt; mix with phosphate or lithium hydroxide, under inert atmosphere protection through 300-350 ℃ and 500-800 ℃ roasting synthesizing iron lithium phosphate stage by stage.The advantage of high temperature method is that technique is simple, easily realizes industrialization, but the common mixing of reactant is inhomogeneous, and the product particle is easily grown up, and discharges ammonia in course of reaction, is difficult to obtain pure LiFePO 4.
Liquid phase method comprises sol-gel process, coprecipitation, hydrothermal synthesis method etc.
Sol-gel process (Chinese patent CN1410349A, [J] Electrochemical and Solid-State Letters, 5 (3) A47-A50) is by compatible Li
+, Fe
2+Or Fe
3+, PO
4 3-The aqueous solution select suitable organic sequestering agent, make it to add thermosetting colloidal sol and gel, then obtain LiFePO 4 by sintering.Sol-gal process can make iron, phosphate radical and lithium realize that molecular level mixes, and also realizes easily mixing, and the resulting materials performance is also more satisfactory, but technique is comparatively complicated, is difficult for expanding production.
Coprecipitation (WO02/083555A2, CN1431147A) under certain condition, lithium hydroxide is joined in the solution that contains ferrous ion and phosphoric acid, and co-precipitation goes out ferrous phosphate and lithium phosphate precursor from solution, and precursor is made LiFePO 4 650-800 ℃ of roasting.All need the inertia protection but the whole process of WO02/083555A2 method comprises the precursor preparation, the ferric iron of oxidizability and nitric acid consume the more expensive ascorbic acid of price, are unfavorable for industrialization.Chinese patent CN1431147A adopts closed container to prepare precursor, has removed protective atmosphere from, but technique is still comparatively complicated, is difficult for expanding production.And still need 5-20 hour high temperature sintering in the later stage, synthetic power consumption is still more serious.
Hydro thermal method and microwave method are fast-developing from the beginning of this year a kind of material preparation methods.These class methods can obtain pure LiFePO4, but usually use special test device such as high-pressure reaction vessel, and there is the uneven shortcoming of bulk materials heating in microwave method, therefore is difficult to satisfy the requirement of large-scale industrialization preparation.
The present invention is directed to the weak point of said method, take ferric phosphate and vanadic oxide as raw material, utilize the chelation of oxalic acid to prepare the presoma of sample.In adopting organic cracking carbothermic method sintering process, organic substance need to melt cracking process before producing reducing gas, produces cracking carbon.The existence of liquid phase can make crystal grain better be coated in this process, also can produce certain influence to the growth of crystal grain simultaneously, to xLiFePO
4YLi
3V
2(PO
4)
3/ C composite material granular pattern and particle diameter distribute and play better control action, have greatly improved the chemical property of material.
Summary of the invention
The object of the invention is, a kind of preparation method of lithium iron phosphate/lithium vanadium phosphate composite material of carbon coating is provided, the method is take ferric phosphate, vanadic oxide as raw material, and ferric phosphate, vanadic oxide and lithium salt compound are mixed, and adds chelating agent, carry out ground and mixed, under inert atmosphere, add carbon source material after the heat treatment, heat temperature raising, roasting, be cooled to room temperature, namely obtain the lithium iron phosphate/lithium vanadium phosphate (xLiFePO of carbon coated
4YLi
3V
2(PO
4)
3/ C) composite material.The method is controlled easily to material composition and product prescription, and Self-adjustment designs the ratio of LiFePO4, phosphoric acid vanadium lithium in the composite material as required, and synthetic lithium iron phosphate/lithium vanadium phosphate product purity is high.The lithium iron phosphate positive material complete in crystal formation that the method obtains, the granule-morphology rule shows excellent normal temperature and low temperature electrochemical performance.40LiFePO by the method for the invention acquisition
4Li
3V
2(PO
4)
3/ C composite material is assembled into test battery and at room temperature reaches 144mAh/g with 150mA/g current discharge specific capacity, in the time of-20 ℃ take 30mA/g current discharge specific capacity as 105mAh/g.The raw material of utilization of the present invention all is large industrial chemicals, and is with low cost, and process route simply, is easily realized industrial-scale production, and boundless application prospect is arranged.
The preparation method of a kind of lithium iron phosphate/lithium vanadium phosphate composite material of the present invention follows these steps to carry out:
A, with ferric phosphate, vanadic oxide, lithium salts, ammonium di-hydrogen phosphate and oxalic acid Fe: V: Li: P: H in molar ratio
2C
2O
4=5-50: 2: 8-53: 8-53: 4.5-27 mixes, and grinds milling time 3-8 hour in mortar;
B, with powder heat treatment under protective gas of step a, air velocity is 0.2-0.6L/min, heat up with the temperature 5-10 ℃/min rate of heat addition, in temperature 300-400 ℃ roasting 5-15 hour, the speed with temperature 1-10 ℃/min is cooled to room temperature again;
C, with adding the carbon source that mass fraction is 5-30% (after decomposing in the composite material Quality Fraction of Carbonium be 1.6%-15.1%) in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, heat treatment under protective gas, typed pressure is 10-40MPa, air velocity is 0.2-0.6L/min, heat up with the temperature 5-10 ℃/min rate of heat addition, again in temperature 650-850 ℃ roasting 5-25 hour;
E, be cooled to room temperature with the speed of temperature 1-10 ℃/min, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Material purity described in the step a is 99.9%.
Lithium salts described in the step a is lithium hydroxide or lithium carbonate.
Employed carbon source is sucrose or glucose among the step c.
Employed protective gas is the mist of argon gas, nitrogen or argon gas and hydrogen or the mist of nitrogen and hydrogen in step b and the steps d, and hydrogen volume content is 2-60% in the mist.
The preparation method of a kind of lithium iron phosphate/lithium vanadium phosphate composite material of the present invention, the method adopts the high temperature solid-state carbothermic method take trivalent ferric phosphate, vanadic oxide and lithium salts as raw material, oxalic acid is chelating agent, organic substance is carbon source, obtains the lithium iron phosphate/lithium vanadium phosphate positive electrode that lithium ion battery is used the high-performance carbon coated by the organic cracking carbothermic method.The present invention controls easily to material composition and product prescription, and Self-adjustment designs the ratio of LiFePO4, phosphoric acid vanadium lithium in the composite material as required, and synthetic lithium iron phosphate/lithium vanadium phosphate product purity is high.The lithium iron phosphate positive material complete in crystal formation that the method obtains, the granule-morphology rule shows excellent normal temperature and low temperature electrochemical performance.40LiFePO by method acquisition of the present invention
4Li
3V
2(PO
4)
3/ C composite material is assembled into test battery and at room temperature reaches 144mAh/g with 150mA/g current discharge specific capacity, in the time of-20 ℃ take 30mA/g current discharge specific capacity as 105mAh/g.The raw material of utilization of the present invention all is large industrial chemicals, and is with low cost, and process route simply, is easily realized industrial-scale production, and boundless application prospect is arranged.
Description of drawings
Fig. 1 is the X-ray diffracting spectrum of the embodiment of the invention 1,2,4,5,6 prepared samples, and wherein, a, b, c, d, e are respectively the collection of illustrative plates of embodiment 1,2,4,5,6 made samples.
Fig. 2 is the stereoscan photograph figure of the prepared sample of the embodiment of the invention 2.
Fig. 3 is the prepared charge-discharge characteristic figure of sample under different temperatures, different charging and discharging currents of the embodiment of the invention 2, when wherein a is room temperature (25 ℃), and the charging and discharging curve under the 150mA/g electric current; When b is-20 ℃, the charging and discharging curve under the 30mA/g electric current.
Fig. 4 is the prepared charge-discharge characteristic figure of sample under different temperatures, different charging and discharging currents of the embodiment of the invention 6, when wherein a is room temperature (25 ℃), and the charging and discharging curve under the 150mA/g electric current; When b is-20 ℃, the charging and discharging curve under the 30mA/g electric current.
Embodiment
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium carbonate, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=50: 2: 53: 53: 27, fully mixes, and grinds milling time 3h in agate mortar;
B, with powder heat treatment under the protective gas nitrogen atmosphere of step a, air velocity is 0.2L/min, heats up with 5 ℃/min of the temperature rate of heat addition, in 300 ℃ of roastings of temperature 5 hours, the speed with 1 ℃/min of temperature was cooled to room temperature again;
C, be 5% carbon source glucose (after decomposing in the composite material Quality Fraction of Carbonium be 1.6%-2.4%) with adding mass fraction in the powder that obtains of step b, ground 1 hour;
D, with the powder pressure forming of step c, heat treatment under the protective gas nitrogen atmosphere, typed pressure is 10MPa, air velocity is 0.2L/min, heats up with 5 ℃/min of the temperature rate of heat addition, again in 650 ℃ of roastings of temperature 5 hours;
E, be cooled to room temperature with the speed of 1 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 2
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium carbonate, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=40: 2: 43: 43: 22, fully mixes, and grinds milling time 5h in agate mortar;
B, with powder heat treatment under the protective gas argon gas atmosphere of step a, air velocity is 0.4L/min, heats up with 7 ℃/min of the temperature rate of heat addition, in 330 ℃ of roastings of temperature 8 hours, the speed with 3 ℃/min of temperature was cooled to room temperature again;
C, be 20% carbon source sucrose (after decomposing in the composite material Quality Fraction of Carbonium be 6.7%-10%) with adding mass fraction in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, heat treatment under the protective gas argon gas atmosphere, typed pressure is 15MPa, air velocity is 0.4L/min, heats up with 7 ℃/min of the temperature rate of heat addition, again in 680 ℃ of roastings of temperature 10 hours;
E, be cooled to room temperature with the speed of 3 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 3
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium hydroxide, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=40: 2: 43: 43: 22, fully mixes, and grinds milling time 5.5h in agate mortar;
B, with powder heat treatment under the protective gas argon gas atmosphere of step a, air velocity is 0.5L/min, heats up with 8 ℃/min of the temperature rate of heat addition, in 350 ℃ of roastings of temperature 10 hours, the speed with 5 ℃/min of temperature was cooled to room temperature again;
C, be 15% carbon source glucose (after decomposing in the composite material Quality Fraction of Carbonium be 4.8%-7.2%) with adding mass fraction in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, heat treatment under the protective gas argon gas atmosphere, typed pressure is 20MPa, air velocity is 0.5L/min, heats up with 8 ℃/min of the temperature rate of heat addition, again in 700 ℃ of roastings of temperature 10 hours;
E, be cooled to room temperature with the speed of 5 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 4
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium carbonate, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=20: 2: 23: 23: 12, fully mixes, and grinds milling time 8h in agate mortar;
B, with powder (hydrogen volume content is 2%) heat treatment under the mist of protective gas argon/hydrogen of step a, air velocity is 0.6L/min, heat up with 10 ℃/min of the temperature rate of heat addition, in 400 ℃ of roastings of temperature 15 hours, the speed with 10 ℃/min of temperature was cooled to room temperature again;
C, be 25% carbon source sucrose (after decomposing in the composite material Quality Fraction of Carbonium be 8.4%-12.6%) with adding mass fraction in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, (hydrogen volume content is 2%) heat treatment under the mist of protective gas argon/hydrogen, typed pressure is 30MPa, air velocity is 0.6L/min, heat up with 10 ℃/min of the temperature rate of heat addition, again in 750 ℃ of roastings of temperature 20 hours;
E, be cooled to room temperature with the speed of 10 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 5
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium carbonate, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=10: 2: 13: 13: 7, fully mixes, and grinds time 4h in agate mortar;
B, with powder (hydrogen volume content is 20%) heat treatment under the mist of protective gas nitrogen/hydrogen of step a, air velocity is 0.4L/min, heat up with 6 ℃/min of the temperature rate of heat addition, in 360 ℃ of roastings of temperature 12 hours, the speed with 2 ℃/min of temperature was cooled to room temperature again;
C, be 30% carbon source sucrose (after decomposing in the composite material Quality Fraction of Carbonium be 10.1%-15.1%) with adding mass fraction in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, (hydrogen volume content is 20%) heat treatment under the mist of protective gas nitrogen/hydrogen, typed pressure is 40MPa, air velocity is 0.3L/min, heat up with 9 ℃/min of the temperature rate of heat addition, again in 850 ℃ of roastings of temperature 25 hours;
E, be cooled to room temperature with the speed of 9 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 6
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium carbonate, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=5: 2: 8: 8: 4.5, fully mixes, and grinds milling time 7h in agate mortar;
B, with powder (hydrogen volume content is 60%) heat treatment under the mist of protective gas argon gas/hydrogen of step a, air velocity is 0.6L/min, heat up with 6.5 ℃/min of the temperature rate of heat addition, in 320 ℃ of roastings of temperature 15 hours, the speed with 5.5 ℃/min of temperature was cooled to room temperature again;
C, be 20% carbon source sucrose (after decomposing in the composite material Quality Fraction of Carbonium be 6.7%-10%) with adding mass fraction in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, (hydrogen volume content is 60%) heat treatment under the mist of protective gas argon gas/hydrogen, typed pressure is 25MPa, air velocity is 0.6L/min, heat up with 6.5 ℃/min of the temperature rate of heat addition, again in 850 ℃ of roastings of temperature 23 hours;
E, be cooled to room temperature with the speed of 6.5 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 7
A, Fe: V: Li: P: H in molar ratio
2C
2O
4Take by weighing ferric phosphate, vanadic oxide, lithium hydroxide, ammonium di-hydrogen phosphate and oxalic acid (material purity be 99.9%) at=5: 2: 8: 8: 4.5, fully mixes, and grinds milling time 4h in agate mortar;
B, with powder (hydrogen volume content is 50%) heat treatment under protective gas argon gas/hydrogen gas mixture of step a, air velocity is 4.5L/min, heat up with 10 ℃/min of the temperature rate of heat addition, in 400 ℃ of roastings of temperature 15 hours, the speed with 10 ℃/min of temperature was cooled to room temperature again;
C, be 10% carbon source sucrose (after decomposing in the composite material Quality Fraction of Carbonium be 3.4%-6.3%) with adding mass fraction in the powder that obtains of step b, ground 1-4 hour;
D, with the powder pressure forming of step c, (hydrogen volume content is 50%) heat treatment under protective gas argon gas/hydrogen gas mixture, typed pressure is 40MPa, air velocity is 0.6L/min, heat up with 10 ℃/min of the temperature rate of heat addition, again in 850 ℃ of roastings of temperature 25 hours;
E, be cooled to room temperature with the speed of 10 ℃/min of temperature, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
Embodiment 8
The composite material of the carbon coated that embodiment 1-7 is prepared evenly mixes in ethanolic solution with conductive agent acetylene black, polyfluortetraethylene of binding element emulsion, the mass ratio of active material, acetylene black and binding agent is 80: 10: 10 (the active material quality comprises the quality of carbon in the material), and then compressing tablet makes positive pole at aluminium foil; Take lithium metal as negative pole, ethylene carbonate, ethylene carbonate and the dimethyl carbonate of 1mol/L lithium hexafluoro phosphate (LiPF6) (volume ratio 1: 1: 1) solution is as electrolyte, the polyethylene of 20 micron thickness is barrier film, be assembled into button test battery (CR 2025), under room temperature (25 ℃) 150mA/g electric current, 40LiFePO
4Li
3V
2(PO
4)
3The specific discharge capacity of/C reaches 144mAh/g, 5LiFePO
4Li
3V
2(PO
4)
3The specific discharge capacity of/C reaches 138mAh/g; At-20 ℃, under the 30mA/g electric current, 40LiFePO
4Li3V
2(PO
4)
3The specific discharge capacity of/C reaches 105mAh/g, 5LiFePO
4Li
3V
2(PO
4)
3The specific discharge capacity of/C reaches 100mAh/g.
Claims (5)
1. the preparation method of a lithium iron phosphate/lithium vanadium phosphate composite material is characterized in that following these steps to carrying out:
A, with ferric phosphate, vanadic oxide, lithium salts, ammonium di-hydrogen phosphate and oxalic acid Fe: V: Li: P: H in molar ratio
2C
20
4=5-50: 2: 8-53: 8-53: 4.5-27 mixes, and grinds milling time 3-8 hour in mortar;
B, with powder heat treatment under protective gas of step a, air velocity is 0.2-0.6L/min, heat up with the temperature 5-10 ℃/min rate of heat addition, in temperature 300-400 ℃ roasting 5-15 hour, the speed with temperature 1-10 ℃/min is cooled to room temperature again;
Add carbon source in c, the powder that step b is obtained, ground 1-4 hour, wherein to account for the mass fraction of the powder that step b obtains be 5-30% to carbon source;
D, with the powder pressure forming of step c, heat treatment under protective gas, typed pressure is 10-40MPa, air velocity is 0.2-0.6L/min, heat up with the temperature 5-10 ℃/min rate of heat addition, again in temperature 650-850 ℃ roasting 5-25 hour;
E, be cooled to room temperature with the speed of temperature 1-10 ℃/min, can obtain the lithium iron phosphate/lithium vanadium phosphate composite material of carbon coated.
2. preparation method according to claim 1, the purity that it is characterized in that ferric phosphate, vanadic oxide, lithium salts, ammonium di-hydrogen phosphate and oxalic acid described in the step a is 99.9%.
3. preparation method according to claim 2 is characterized in that lithium salts described in the step a is lithium hydroxide or lithium carbonate.
4. preparation method according to claim 3 is characterized in that employed carbon source is sucrose or glucose among the step c.
5. preparation method according to claim 4 is characterized in that employed protective gas is the mist of argon gas, nitrogen or argon gas and hydrogen or the mist of nitrogen and hydrogen in step b and the steps d, and hydrogen volume content is 2-60% in the mist.
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| CN103000888B (en) * | 2012-11-28 | 2015-10-14 | 上海交通大学 | Lithium ion battery composite cathode material LiMnPO4-Li3V2 (PO4) 3/C and preparation method thereof |
| CN104269530A (en) * | 2014-09-30 | 2015-01-07 | 中南大学 | Method for hydro-thermal synthesis of lithium iron phosphate-lithium vanadium phosphate composite material |
| CN106784809B (en) * | 2016-11-18 | 2019-07-05 | 山东精工电子科技有限公司 | A kind of LiVOPO4/LiMPO4/ C composite material of core-shell structure and preparation method |
| CN107946566B (en) * | 2017-11-16 | 2021-01-01 | 贝特瑞（天津）纳米材料制造有限公司 | Composite LiFePO4-LiMPO4Positive electrode material and preparation method thereof |
| WO2023108639A1 (en) * | 2021-12-17 | 2023-06-22 | 宁德时代新能源科技股份有限公司 | Positive electrode composite material for lithium ion secondary battery, and lithium ion secondary battery |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101114709A (en) * | 2007-08-10 | 2008-01-30 | 武汉大学 | Lithium ion battery composite anode material LiFePO4-Li3V2(PO4)3/C and method for making same |
| CN101640263A (en) * | 2009-08-27 | 2010-02-03 | 杭州海孚新能源科技有限公司 | Lithium ion battery composite cathode material and preparation method thereof |
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| CN101640263A (en) * | 2009-08-27 | 2010-02-03 | 杭州海孚新能源科技有限公司 | Lithium ion battery composite cathode material and preparation method thereof |
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