CN115626622A - Nanocrystalline lithium manganese iron phosphate precursor and preparation method and application thereof - Google Patents

Nanocrystalline lithium manganese iron phosphate precursor and preparation method and application thereof Download PDF

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CN115626622A
CN115626622A CN202211193857.0A CN202211193857A CN115626622A CN 115626622 A CN115626622 A CN 115626622A CN 202211193857 A CN202211193857 A CN 202211193857A CN 115626622 A CN115626622 A CN 115626622A
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manganese
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phosphate precursor
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李健
司徒白雪
金晶
李良
柏鑫焱
陆伟俊
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Shenzhen Zhongxinneng Technology Co ltd
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Abstract

The invention relates to the technical field of lithium ion battery material preparation, and discloses a nanocrystalline lithium manganese iron phosphate precursor, a preparation method and application thereof; the nanocrystalline lithium manganese iron phosphate precursor prepared by the invention has high purity, the single crystal particles are all nanocrystalline particles, and the nanocrystalline lithium manganese iron phosphate precursor can be used for preparing monocrystalline particle-nanocrystallized lithium manganese iron phosphate, can effectively improve the conductivity of the monocrystalline particle-nanocrystallized lithium manganese iron phosphate precursor, and solves the problem that the conductivity of lithium manganese iron phosphate serving as a battery anode material in the prior art is poor.

Description

Nanocrystalline lithium manganese iron phosphate precursor and preparation method and application thereof
Technical Field
The invention relates to the technical field of lithium ion battery material preparation, in particular to a nanocrystalline lithium manganese iron phosphate precursor and a preparation method and application thereof.
Background
The energy density is the size of energy stored in a certain space or mass material per unit, the energy density = gram volume, voltage platform divided by volume, therefore, the energy density is only related to the gram volume and the voltage platform of the material at a certain volume, the voltage platform is related to a physical structure, the voltage platform of the lithium iron phosphate material is 3.4V, the gram volume of the lithium iron phosphate is close to 160mAh/g at present, the theoretical gram volume of the lithium iron phosphate is 170mAh/g, the theoretical limit is already close to, and the possibility of improving the energy density of the lithium iron phosphate is lower theoretically.
At present, lithium manganese iron phosphate can be selected to replace lithium iron phosphate, and has the advantages of low cost, high thermal stability, high safety and the like of lithium manganese iron phosphate, so that the defects of low energy density and poor low-temperature stability of lithium manganese iron phosphate are overcome, but the lithium manganese iron phosphate also has the problems of poor conductivity, rate capability, poor cycle performance and the like.
In the prior art, the conductivity of the material can be effectively improved through the nanocrystallization of single crystal particles.
Disclosure of Invention
The invention aims to provide a nanocrystalline lithium manganese iron phosphate precursor, a preparation method and application thereof, and aims to solve the problem that lithium manganese iron phosphate in the prior art has poor conductivity as a battery anode material.
The invention is realized in such a way, and in a first aspect, the invention provides a preparation method of a nanocrystalline lithium iron manganese phosphate precursor, which comprises the following steps:
s1: preparing raw materials; the raw materials comprise iron powder, manganese powder, phosphoric acid and oxalic acid;
s2: adding the iron powder and the manganese powder into the phosphoric acid and the oxalic acid, heating and stirring to generate a primary material;
s3: performing ball milling treatment on the primary material to generate a secondary material;
s4: performing spray granulation treatment on the secondary material to generate spherical particle powder;
s5: and carrying out high-temperature calcination treatment on the spherical particle powder to generate a nanocrystalline lithium manganese iron phosphate precursor.
In one embodiment, the proportion standard of the raw materials in S1 is that the molar ratio of manganese, iron and phosphorus is 1-x: x:1, x is more than 0 and less than or equal to 0.4.
In one embodiment, the S2 includes:
s21: dissolving the phosphoric acid and the oxalic acid in deionized water to prepare a mixed acid solution;
s22: adding the iron powder and the manganese powder into the mixed acid solution;
s23: and heating and stirring the mixed acid solution added with the iron powder and the manganese powder to generate the primary material.
In one embodiment, the particle size of the iron and manganese powders is <100 μm.
In one embodiment, the temperature of heating in S2 is 40-80 ℃.
In one embodiment, the reaction time for stirring in S2 is 5 to 15 hours.
In one embodiment, the reaction time of the ball milling treatment in S3 is 5 to 15 hours.
In one embodiment, the temperature of the high-temperature calcination in the S5 is 500-750 ℃.
In one embodiment, the time of the heat preservation treatment in S5 is 6 to 20 hours.
In a second aspect, the invention provides a nanocrystalline lithium manganese iron phosphate precursor, which is prepared by the preparation method of the nanocrystalline lithium manganese iron phosphate precursor in the first aspect, wherein the chemical general formula of the lithium manganese iron phosphate is Mn 1-x Fe x PO 4 Wherein x is more than 0 and less than or equal to 0.4.
In a third aspect, the invention provides a lithium ion battery anode material, which is prepared from the nanocrystalline lithium iron manganese phosphate precursor in the second aspect, and the chemical general formula of the lithium ion battery material is LiMn 1- x Fe x PO 4 Wherein x is more than 0 and less than or equal to 0.4.
The invention provides a nanocrystalline lithium manganese iron phosphate precursor, a preparation method and an application thereof, and the nanocrystalline lithium manganese iron phosphate precursor has the following beneficial effects:
1. the nanocrystalline lithium manganese iron phosphate precursor has high finished product purity, single crystal particles are nanoscale particles, and the nanocrystalline lithium manganese iron phosphate precursor can be used for preparing monocrystalline particle nano lithium manganese iron phosphate, can effectively improve the conductivity of the monocrystalline particle nano lithium manganese iron phosphate, and solves the problem that the conductivity of lithium manganese iron phosphate serving as a battery anode material in the prior art is poor.
2. The method adopts the iron powder and the manganese powder to prepare the nanocrystalline lithium manganese iron phosphate precursor, has simplified process and low comprehensive cost, does not discharge waste gas in the production process, and is environment-friendly.
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Fig. 1 is a schematic diagram illustrating specific steps of a method for preparing a nanocrystalline lithium manganese iron phosphate precursor according to an embodiment of the present invention;
fig. 2 is a schematic diagram of specific steps of a method S2 for preparing a nanocrystalline lithium manganese iron phosphate precursor according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The same or similar reference numerals in the drawings of the present embodiment correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. based on the orientation or positional relationship shown in the drawings, it is only for convenience of describing the present invention and simplifying the description, but it is not intended to indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and are not to be construed as limiting the present patent, and the specific meaning of the terms may be understood by those skilled in the art according to specific circumstances.
The following describes the implementation of the present invention in detail with reference to specific embodiments.
Referring to FIG. 1, a preferred embodiment of the present invention is provided.
In a first aspect, the invention provides a method for preparing a nanocrystalline lithium iron manganese phosphate precursor, comprising the following steps:
s1: and (3) batching the raw materials.
Specifically, the chemical formula of the lithium manganese iron phosphate is as follows: liMn 1-x Fe x PO 4 The invention prepares a lithium manganese iron phosphate precursor for preparing lithium manganese iron phosphate, namely Mn 1-x Fe x PO 4 (ii) a As can be seen, mn 1-x Fe x PO 4 The lithium iron manganese phosphate precursor comprises four elements of manganese (Mn), iron (Fe), phosphorus (P) and oxygen (O), so the four elements need to be provided in a raw material for preparing the lithium iron manganese phosphate precursor.
More specifically, the iron element is derived from iron powder, the manganese element is derived from manganese powder, and the phosphorus element is derived from phosphoric acid (H) 3 PO 4 ) The oxygen element is derived from phosphoric acid and oxalic acid (H) 2 C 2 O 4 )。
It is understood that the final product Mn is produced 1-x Fe x PO 4 The proportions of medium manganese, iron and phosphorus are fixed values, and the proportions of iron powder, manganese powder, phosphoric acid and oxalic acid in the raw materials fluctuate within a certain range on the premise of considering the consumption in the preparation process.
More specifically, the proportion standard of the raw materials is that the molar ratio of manganese, iron and phosphorus is 1-x: x:1,0 < x is not more than 0.4, that is, the molar ratio of manganese, iron and phosphorus in the iron powder, manganese powder, phosphoric acid and oxalic acid in the raw materials satisfies x:1-x:1,0 < x ≦ 0.4, where the phosphorus element may be in appropriate excess to aid in subsequent processing.
S2: adding phosphoric acid and oxalic acid into iron powder and manganese powder, heating and stirring to generate a primary material;
specifically, raw materials prepared in a predetermined ratio need to be mixed, and the mixture is heated and stirred to generate a primary material.
More specifically, the heating temperature is 40-80 ℃ and the reaction time with stirring is 5-15 hours.
S3: and performing ball milling treatment on the primary material to generate a secondary material.
Specifically, the generated primary material is added into a high-energy ball mill for ball milling treatment.
In the ball milling treatment, the hard balls are strongly collided, ground and stirred with the raw material by using the rotation or vibration of the ball mill to crush the powder into nano-sized particles, and the high-energy ball mill can perform the ball milling treatment.
More specifically, after the primary material is subjected to ball milling treatment by the high-energy ball mill, a secondary material is generated.
More specifically, the reaction time of the ball-milling treatment is 5 to 15 hours.
S4: and carrying out spray granulation treatment on the secondary material to generate spherical particle powder.
Specifically, spray granulation is a granulation method in which a slurry or a solution is sprayed into a granulation tower, and the slurry or the solution is dried and agglomerated under the action of hot air spray, thereby obtaining spherical granules. The method is widely used for producing catalysts with various particle sizes or other particles with required particle sizes. The method is suitable for experiments and small-scale production, and the particle balls have good precision and uniform particles.
It is understood that, in the present invention, the primary material is subjected to spray granulation, and the primary material can be manufactured into a spherical granular powder.
S5: and (3) carrying out high-temperature calcination treatment on the spherical particle powder to generate a nanocrystalline lithium manganese iron phosphate precursor.
Specifically, the nanocrystalline manganese iron phosphate prepared by the invention is spherical particles with the average single crystal particle size of less than 100nm and the average secondary particle size of 15-35 μm, and the spherical particle powder generated in S4 cannot meet the standard, so that the spherical particle powder needs to be subjected to high-temperature calcination and heat preservation treatment to generate the nanocrystalline manganese iron phosphate precursor meeting the standard.
More specifically, the temperature of the high-temperature calcination is 500 ℃ to 750 ℃.
More specifically, when the calcining temperature reaches the requirement, the heat preservation treatment is carried out for 6 to 20 hours, and it can be understood that the nanocrystalline phosphoric acid series cathode material can be generated only by preserving the heat for 6 to 20 hours under the temperature condition of 500 to 700 ℃.
It should be noted that the nanocrystalline material is a material composed of crystals having a nanoscale size (1 to 10 nm), and more specifically, the crystals are a structure in which a large number of microscopic substance units (atoms, ions, molecules, etc.) are arranged in order according to a certain rule.
It can be understood that the nanocrystalline lithium iron manganese phosphate precursor prepared by high-temperature calcination and heat preservation is of a monolithic structure, i.e., a plurality of nanoscale lithium iron manganese phosphate precursors are combined into a large crystal.
The invention provides a nanocrystalline lithium manganese iron phosphate precursor, a preparation method and an application thereof, and the nanocrystalline lithium manganese iron phosphate precursor has the following beneficial effects:
1. the prepared nanocrystalline lithium manganese iron phosphate precursor has high finished product purity, and single crystal particles are nano-scale particles, and the nanocrystalline lithium manganese iron phosphate precursor can be used for preparing monocrystalline particle nano lithium manganese iron phosphate, can effectively improve the conductivity of the monocrystalline particle nano lithium manganese iron phosphate precursor, and solves the problem that the conductivity of lithium manganese iron phosphate serving as a battery anode material in the prior art is poor.
2. The method adopts the iron powder and the manganese powder to prepare the nanocrystalline lithium manganese iron phosphate precursor, has simplified process and low comprehensive cost, does not discharge waste gas in the production process, and is environment-friendly.
Referring to FIG. 2:
in some embodiments, S2 comprises:
s21: phosphoric acid and oxalic acid are dissolved in deionized water to produce a mixed acid solution.
The deionized water is pure water from which impurities in the form of ions are removed, so that the neutralization reaction of alkaline substances existing in a common water source with phosphoric acid and oxalic acid can be avoided, and the phosphoric acid and oxalic acid are prevented from being consumed additionally.
Specifically, phosphoric acid and oxalic acid are mixed and dissolved in deionized water to make a mixed acid solution.
S22: adding iron powder and manganese powder into the mixed acid solution.
Specifically, iron powder and manganese powder are prepared according to a predetermined proportion and then added into the mixed acid solution.
S23: the mixed acid solution added with the iron powder and the manganese powder is heated and stirred to generate a primary material.
In particular, under the condition of high heat, the iron powder and the manganese powder can react with the mixed acid solution more efficiently.
More specifically, stirring is a commonly used operation in organic manufacturing experiments, and aims to enable sufficient mixing of reactants and avoid side reactions or decomposition of organic substances caused by nonuniform concentration of reactants, local excess, nonuniform heating.
It will be appreciated that heating and stirring can be effective to promote the formation of a primary mass.
More specifically, the heating temperature is 40-80 ℃ and the reaction time with stirring is 5-15 hours.
In some embodiments, the particle size of the iron and manganese powders is <100 μm.
It can be understood that the fine iron and manganese powders can react with the mixed acid solution more efficiently, and if the particle diameter of the iron and manganese powders is too large, the contact area of the iron and manganese with the mixed acid solution per unit time is small, resulting in low reaction efficiency.
Based on the above embodiments, the present invention provides embodiments 1, 2 and 3 to provide specific embodiments with detailed data, so as to further explain the present invention:
example 1:
specifically, when the nanocrystalline ferromanganese phosphate precursor is Mn 1-x Fe x PO 4 (x = 0.2), mn 1-x ：Fe x The proportion of each element in P is 0.8:0.2:1.
more specifically, 12.4kg of 85% phosphoric acid is selected as phosphoric acid, and 5kg of oxalic acid is selected as oxalic acid; both are dissolved in deionized water to prepare mixed acid solution.
More specifically, 4.4kg of manganese powder is used, 1.4kg of iron powder is used, and the particle sizes of the manganese powder and the iron powder are both smaller than 100 mu m.
More specifically, the heating temperature is 50 ℃, the stirring and soaking time is 15h, and the obtained primary material is put into a high-energy mill for grinding reaction for 10h to generate a secondary material.
More specifically, the secondary material is put into a centrifugal sprayer for spray drying treatment to obtain spherical particles of 15-35 μm.
More specifically, the spray-dried spherical particle powder is calcined in an air furnace at 650 ℃ and is kept warm for 11 hours to generate a nanocrystalline lithium manganese iron phosphate precursor.
More specifically, the nanocrystalline lithium manganese iron phosphate precursor is subjected to jet milling treatment to generate a spherical lithium manganese iron phosphate precursor.
It should be noted that the nanocrystalline lithium manganese iron phosphate precursor obtained by high-temperature calcination and heat preservation is of a monolithic structure, and at this time, the nanocrystalline lithium manganese iron phosphate precursor needs to be subjected to crushing treatment.
It should be noted that the jet milling is to carry out ultrafine grinding on solid materials by using the energy of high-speed air flow or superheated steam, and can effectively crush the nanocrystalline lithium manganese iron phosphate precursor into a spherical lithium manganese iron phosphate precursor with the single crystal particle size of 80-200 nm and the secondary particle size range of 5-25 microns.
In example 1, mn was prepared by controlling the ratio of iron powder to manganese powder 1-x ：Fe x The proportion of each element in P is 0.8:0.2: the lithium manganese iron phosphate precursor 1 can be used for preparing single-crystallized lithium manganese iron phosphate, and the single-crystallized lithium manganese iron phosphate has better conductivity and can serve as a positive electrode material of a lithium battery.
Example 2:
specifically, when the nanocrystalline ferromanganese phosphate precursor is Mn 1-x Fe x PO 4 (x = 0.3), mn 1-x ：Fe x The proportion of each element in P is 0.7:0.3:1.
more specifically, 12.4kg of 85% phosphoric acid is selected as the phosphoric acid, and 5kg of oxalic acid is selected as the oxalic acid; both are dissolved in deionized water to prepare mixed acid solution.
More specifically, 3.85kg of manganese powder and 1.71kg of iron powder are used, and the particle sizes of the manganese powder and the iron powder are both smaller than 100 mu m.
More specifically, the heating temperature is 50 ℃, the stirring and soaking time is 15h, and the obtained primary material is put into a high-energy mill for grinding reaction for 10h to generate a secondary material.
More specifically, the secondary material is put in a centrifugal sprayer for spray drying treatment to obtain spherical particles of 15-35 mu m.
More specifically, the spray-dried spherical particle powder is calcined in an air furnace at 650 ℃ and is kept warm for 11 hours to generate a nanocrystalline lithium manganese iron phosphate precursor.
More specifically, the nanocrystalline lithium manganese iron phosphate precursor is subjected to airflow crushing treatment to generate a spherical lithium manganese iron phosphate precursor with a single crystal particle size of 80-200 nanometers and a secondary particle size range of 5-25 micrometers.
In example 2, mn was prepared by controlling the ratio of iron powder to manganese powder as in example 1 1-x ：Fe x The proportion of each element in P is 0.7:0.3: the lithium manganese iron phosphate precursor 1 can be used for preparing single-crystallized lithium manganese iron phosphate, and the single-crystallized lithium manganese iron phosphate has better conductivity and can serve as a positive electrode material of a lithium battery.
Example 3:
specifically, when the nanocrystalline ferromanganese phosphate precursor is Mn 1-x Fe x PO 4 (x = 0.4), mn 1-x ：Fe x The proportion of each element in P is 0.6:0.4:1.
more specifically, 12.4kg of 85% phosphoric acid is selected as phosphoric acid, and 5kg of oxalic acid is selected as oxalic acid; both are dissolved in deionized water to prepare mixed acid solution.
More specifically, 3.85kg of manganese powder and 1.71kg of iron powder are used, and the particle sizes of the manganese powder and the iron powder are both smaller than 100 mu m.
More specifically, the heating temperature is 80 ℃, the stirring and soaking time is 10 hours, and the obtained primary material is put into a high-energy mill for grinding reaction for 15 hours to generate a secondary material.
More specifically, the secondary material is put into a centrifugal sprayer for spray drying treatment to obtain spherical particles of 15-35 μm.
More specifically, the spray-dried spherical particle powder is calcined in an air furnace at 650 ℃ and is kept warm for 15 hours to generate a nanocrystalline lithium manganese iron phosphate precursor.
More specifically, the nanocrystalline lithium manganese iron phosphate precursor is subjected to airflow crushing treatment to generate a spherical lithium manganese iron phosphate precursor with a single crystal particle size of 80-200 nanometers and a secondary particle size range of 5-25 micrometers.
In example 3, mn was prepared by controlling the ratio of iron powder to manganese powder in the same manner as in examples 1 and 2 1-x ：Fe x The proportion of each element in P is 0.6:0.4: the lithium manganese iron phosphate precursor 1 can be used for preparing single-crystallized lithium manganese iron phosphate, and the single-crystallized lithium manganese iron phosphate has better conductivity and can serve as a positive electrode material of a lithium battery.
In a second aspect, the invention provides a nanocrystalline lithium manganese iron phosphate precursor, which is prepared by the preparation method of the nanocrystalline lithium manganese iron phosphate precursor in the first aspect, wherein the chemical general formula of the lithium manganese iron phosphate is Mn 1-x Fe x PO 4 Wherein x is more than 0 and less than or equal to 0.4.
In a third aspect, the invention provides a lithium ion battery anode material, which is prepared from the nanocrystalline lithium iron manganese phosphate of the second aspectThe precursor is prepared, and the chemical general formula of the lithium ion battery material is LiMn 1- x Fe x PO 4 Wherein x is more than 0 and less than or equal to 0.4.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (10)

1. A preparation method of a nanocrystalline lithium manganese iron phosphate precursor is characterized by comprising the following steps:
s1: burdening the raw materials; the raw materials comprise iron powder, manganese powder, phosphoric acid and oxalic acid;
s2: adding the iron powder and the manganese powder into the phosphoric acid and the oxalic acid, heating and stirring to generate a primary material;
s3: performing ball milling treatment on the primary material to generate a secondary material;
s4: carrying out spray granulation treatment on the secondary material to generate spherical particle powder;
s5: and carrying out high-temperature calcination and heat preservation treatment on the spherical particle powder to generate a nanocrystalline lithium manganese iron phosphate precursor.
2. The method for preparing the nanocrystalline lithium iron manganese phosphate precursor according to claim 1, wherein the proportioning standard of the raw materials in S1 is that the molar ratio of manganese, iron and phosphorus is 1-x: x:1, x is more than 0 and less than or equal to 0.4.
3. The method for preparing a nanocrystalline lithium iron manganese phosphate precursor according to claim 1, wherein S2 includes:
s21: dissolving the phosphoric acid and the oxalic acid in deionized water to prepare a mixed acid solution;
s22: adding the iron powder and the manganese powder into the mixed acid solution;
s23: and heating and stirring the mixed acid solution added with the iron powder and the manganese powder to generate the primary material.
4. The method of claim 1, wherein the particle size of the iron powder and the manganese powder is less than 100 μm.
5. The method for preparing the nanocrystalline lithium iron manganese phosphate precursor according to claim 1, wherein the heating temperature in S2 is 40-80 ℃, and the stirring reaction time in S2 is 5-15 hours.
6. The method for preparing the nanocrystalline lithium iron manganese phosphate precursor of claim 1, wherein the reaction time of the ball milling treatment in S3 is 5-15 hours.
7. The method for preparing the nanocrystalline lithium iron manganese phosphate precursor according to claim 1, wherein the temperature for the high-temperature calcination in S5 is 500 ℃ to 750 ℃.
8. The method for preparing the nanocrystalline lithium iron manganese phosphate precursor according to claim 1, wherein the heat preservation treatment in S5 is performed for 6 to 20 hours.
9. A nanocrystalline lithium manganese iron phosphate precursor, characterized in that the nanocrystalline lithium manganese iron phosphate precursor is prepared by the method for preparing the nanocrystalline lithium manganese iron phosphate precursor according to claims 1-8, and the chemical general formula of the lithium manganese iron phosphate is Mn 1-x Fe x PO 4 Wherein x is more than 0 and less than or equal to 0.4.
10. A lithium ion battery anode material, characterized in that the lithium ion battery anode material is prepared from the nanocrystalline lithium manganese iron phosphate precursor of claim 9, and the chemical general formula of the lithium ion battery material is LiMn 1-x Fe x PO 4 Wherein x is more than 0 and less than or equal to 0.4.
CN202211193857.0A 2022-09-28 2022-09-28 Nanocrystalline lithium manganese iron phosphate precursor and preparation method and application thereof Pending CN115626622A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102867954A (en) * 2012-09-13 2013-01-09 清华大学 Method for synthesizing lithium iron phosphate anode material by adopting emulsion liquid phase
CN102983328A (en) * 2012-11-23 2013-03-20 清华大学 Method for preparing nanocrystalline lithium iron phosphate anode material from ferrous powder
CN104577119A (en) * 2015-01-04 2015-04-29 合肥国轩高科动力能源股份公司 Cathode material LiMn1-xFexPO4 for lithium ion cell and preparation method of cathode material LiMn1-xFexPO4
CN111908442A (en) * 2020-08-07 2020-11-10 上海华谊（集团）公司 Ferromanganese phosphate, lithium iron manganese phosphate and preparation method thereof
CN114516626A (en) * 2022-02-18 2022-05-20 江苏协鑫锂电科技有限公司 Preparation method of phosphate anode material

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102867954A (en) * 2012-09-13 2013-01-09 清华大学 Method for synthesizing lithium iron phosphate anode material by adopting emulsion liquid phase
CN102983328A (en) * 2012-11-23 2013-03-20 清华大学 Method for preparing nanocrystalline lithium iron phosphate anode material from ferrous powder
CN104577119A (en) * 2015-01-04 2015-04-29 合肥国轩高科动力能源股份公司 Cathode material LiMn1-xFexPO4 for lithium ion cell and preparation method of cathode material LiMn1-xFexPO4
CN111908442A (en) * 2020-08-07 2020-11-10 上海华谊（集团）公司 Ferromanganese phosphate, lithium iron manganese phosphate and preparation method thereof
CN114516626A (en) * 2022-02-18 2022-05-20 江苏协鑫锂电科技有限公司 Preparation method of phosphate anode material

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