CN110380025B - Carbon-coated lithium iron phosphate process, prepared carbon-coated lithium iron phosphate and application thereof - Google Patents
Carbon-coated lithium iron phosphate process, prepared carbon-coated lithium iron phosphate and application thereof Download PDFInfo
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 89
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 89
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 27
- 230000008569 process Effects 0.000 title claims abstract description 16
- 238000000576 coating method Methods 0.000 claims abstract description 34
- 239000002245 particle Substances 0.000 claims abstract description 31
- 229910000398 iron phosphate Inorganic materials 0.000 claims abstract description 26
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 claims abstract description 25
- 239000002002 slurry Substances 0.000 claims abstract description 23
- 239000000463 material Substances 0.000 claims abstract description 21
- 239000011248 coating agent Substances 0.000 claims abstract description 19
- 238000006722 reduction reaction Methods 0.000 claims abstract description 14
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims abstract description 12
- 229910052808 lithium carbonate Inorganic materials 0.000 claims abstract description 12
- 238000001035 drying Methods 0.000 claims abstract description 8
- 238000002156 mixing Methods 0.000 claims abstract description 8
- 239000007791 liquid phase Substances 0.000 claims abstract description 7
- 239000007787 solid Substances 0.000 claims abstract description 7
- VYFYYTLLBUKUHU-UHFFFAOYSA-N dopamine Chemical compound NCCC1=CC=C(O)C(O)=C1 VYFYYTLLBUKUHU-UHFFFAOYSA-N 0.000 claims description 18
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims description 11
- 229910001416 lithium ion Inorganic materials 0.000 claims description 11
- 229960003638 dopamine Drugs 0.000 claims description 9
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 claims description 8
- 239000008103 glucose Substances 0.000 claims description 8
- 238000000227 grinding Methods 0.000 claims description 6
- 238000003756 stirring Methods 0.000 claims description 6
- CTENFNNZBMHDDG-UHFFFAOYSA-N Dopamine hydrochloride Chemical compound Cl.NCCC1=CC=C(O)C(O)=C1 CTENFNNZBMHDDG-UHFFFAOYSA-N 0.000 claims description 4
- 229960001149 dopamine hydrochloride Drugs 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- 238000001694 spray drying Methods 0.000 claims description 4
- 238000003763 carbonization Methods 0.000 claims description 3
- 239000007774 positive electrode material Substances 0.000 claims description 3
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 238000010981 drying operation Methods 0.000 claims description 2
- 125000002791 glucosyl group Chemical group C1([C@H](O)[C@@H](O)[C@H](O)[C@H](O1)CO)* 0.000 claims description 2
- 239000008187 granular material Substances 0.000 claims 1
- 230000035484 reaction time Effects 0.000 claims 1
- 239000002131 composite material Substances 0.000 abstract description 4
- 239000003575 carbonaceous material Substances 0.000 abstract description 2
- 239000011159 matrix material Substances 0.000 abstract description 2
- 239000002086 nanomaterial Substances 0.000 abstract 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 5
- 229910052744 lithium Inorganic materials 0.000 description 5
- 239000000523 sample Substances 0.000 description 5
- 239000004576 sand Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000003638 chemical reducing agent Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000011065 in-situ storage Methods 0.000 description 4
- 239000002243 precursor Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000010410 layer Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000010008 shearing Methods 0.000 description 3
- 229910010710 LiFePO Inorganic materials 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 239000010405 anode material Substances 0.000 description 2
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 2
- 239000010406 cathode material Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- 238000009830 intercalation Methods 0.000 description 2
- 230000002687 intercalation Effects 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000003760 magnetic stirring Methods 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 229910052493 LiFePO4 Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- ZTOZIUYGNMLJES-UHFFFAOYSA-K [Li+].[C+4].[Fe+2].[O-]P([O-])([O-])=O Chemical compound [Li+].[C+4].[Fe+2].[O-]P([O-])([O-])=O ZTOZIUYGNMLJES-UHFFFAOYSA-K 0.000 description 1
- QSNQXZYQEIKDPU-UHFFFAOYSA-N [Li].[Fe] Chemical compound [Li].[Fe] QSNQXZYQEIKDPU-UHFFFAOYSA-N 0.000 description 1
- ZSYNKHJUSDFTCQ-UHFFFAOYSA-N [Li].[Fe].P(O)(O)(O)=O Chemical compound [Li].[Fe].P(O)(O)(O)=O ZSYNKHJUSDFTCQ-UHFFFAOYSA-N 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 230000008570 general process Effects 0.000 description 1
- 238000001027 hydrothermal synthesis Methods 0.000 description 1
- -1 iron ions Chemical class 0.000 description 1
- 230000003446 memory effect Effects 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000004537 pulping Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000010532 solid phase synthesis reaction Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
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- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
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- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
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- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
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Abstract
The invention discloses a carbon-coated lithium iron phosphate process, prepared carbon-coated lithium iron phosphate and application thereof, wherein the process comprises the following steps: s1, mixing iron phosphate, lithium carbonate and a first organic carbon source to prepare slurry, and sanding solid particles in the slurry; s2, drying the slurry processed in the step S1 to obtain particles, and carrying out liquid phase coating on the particles by using a second organic carbon source; and S3, reducing and curing the material processed in the step S2 to obtain the carbon-coated lithium iron phosphate. The lithium iron phosphate/carbon composite nanomaterial is prepared by a two-step multilayer carbon-coating method, and carbon is compounded into a matrix material while lithium iron phosphate is obtained by utilizing multistep carbon coating and reduction reaction, so that the problem of uneven coating of a carbon material in the lithium iron phosphate is solved.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a carbon-coated lithium iron phosphate process, prepared carbon-coated lithium iron phosphate and application thereof.
Background
The lithium ion battery has the advantages of large energy density, high average output voltage, low self-discharge, no memory effect, long service life and the like, and is widely applied to the fields of various portable devices, electric automobiles, aerospace, medicine, energy storage and the like, and the electrical property of the lithium ion battery mainly depends on a lithium ion anode material. Lithium iron phosphate is a common cathode material for lithium ion batteries. The traditional lithium iron phosphate is prepared by mixing an iron source, a lithium source and a phosphorus source in a certain proportion and then directly reacting the mixture to form phosphoric acid by a one-step method (a hydrothermal method, a high-temperature solid-phase method, a mechanochemical method and a microwave method)However, the general process of the method is complex to operate, has high requirements on equipment, and is not suitable for large-scale industrial production. At present, iron phosphate products with standardized quality are generally adopted in some industrial production as precursors to prepare lithium iron phosphate materials. The method for further preparing the lithium iron material by adopting the iron phosphate precursor is simple and feasible, has controllable quality and better electrochemical property performance, and therefore, the method becomes a main method for preparing the lithium iron phosphate in the lithium battery industry. Mixing iron phosphate (FePO)4) Preparation of lithium iron phosphate (LiFePO) as precursor4) In the process, besides the need of adding a lithium source for the subsequent lithium ion desorption/intercalation, more importantly, the need of adding Fe in the original precursor3+Reduction to Fe2+I.e. mainly lithium intercalation and reduction processes. The reducing process needs to provide a certain reducing agent and a protective atmosphere, the reducing agent is diversified in types, but based on the fact that the inherent conductivity of the lithium iron phosphate material is poor, carbon is usually selected as an additive, and the reducing agent can be used for reducing iron ions and can increase the conductivity of the material. However, the choice, amount and location of the carbon source additive in the lithium iron phosphate preparation process will directly affect the microstructure and electrochemical properties of the composite material. In order to perfectly bring the conductivity and reducibility of carbon into full play, a plurality of researchers research iron phosphate carbon-coating processes, and the doping of the carbon nanotube into lithium iron phosphate, coating type, doping type and the like, which improve the conductivity of the lithium iron phosphate, but the technical method mainly focuses on the doping of the carbon and the lithium iron phosphate material, cannot form a complete coating layer on the outside under the low-temperature condition, and has a limited improvement level on the electrochemical performance of the lithium iron phosphate. Therefore, a carbon coating process for lithium iron phosphate still needs to be further improved.
Disclosure of Invention
The first technical problem to be solved by the invention is as follows: provides a lithium iron phosphate carbon coating process with good carbon coating effect.
The second technical problem to be solved by the invention is: provides the carbon-coated lithium iron phosphate prepared by the process.
The third technical problem to be solved by the invention is: provides an application of the carbon-coated lithium iron phosphate.
In order to solve the first technical problem, the invention adopts the technical scheme that: a carbon-coating process for lithium iron phosphate comprises the following steps:
s1, mixing iron phosphate, lithium carbonate and a first organic carbon source to prepare a slurry, and grinding solid particles in the slurry (preferably, grinding operation is performed through sand grinding so that the particles are more refined and uniform); then sanding the solid particles in the slurry;
s2, drying the slurry processed in the step S1 to obtain particles, and carrying out liquid phase coating on the particles by using a second organic carbon source;
and S3, reducing and curing the material processed in the step S2 to obtain the carbon-coated lithium iron phosphate.
Further, the first organic carbon source is an organic carbon source with reducibility; preferably, the first organic carbon source is glucose.
Further, the mass ratio of the iron phosphate to the lithium carbonate to the first organic carbon source is (100-102): (25-28): (10-12.5), preferably, the mass ratio of the iron phosphate to the lithium carbonate to the first organic carbon source is 20:5: 2.
Further, in the pulping process of the step S1, water is added according to the mass ratio of the solid in the total mass of the pulp being 20-30%; preferably, the mass proportion of the solid is 25%.
Further, in the step S1, the particle size of the slurry is controlled to be less than 0.4-0.6 μm through sanding operation.
Further, the drying operation in step S2 is spray drying.
Further, in the step S2, the second organic carbon source is dopamine, and the second organic carbon source liquid phase coating operation is to add the dried particles into a dopamine hydrochloride solution with a pH of 8 to 9, and react under a stirring state.
Preferably, the addition amount of the dopamine is (0.1-1)% of the mass of the particles, and preferably 0.5%.
Further, the reduction curing operation in step S3 is to perform carbonization reduction at 760℃ × 8h in an Ar atmosphere furnace.
In order to solve the second technical problem, the invention adopts the technical scheme that: the carbon-coated lithium iron phosphate is prepared by the process.
In order to solve the third technical problem, the invention adopts the technical scheme that: an application of carbon-coated lithium iron phosphate in the preparation of a lithium ion battery.
A positive active material in the lithium ion battery comprises the carbon-coated lithium iron phosphate.
The invention has the beneficial effects that: the method mainly considers the in-situ reduction of carbon in the lithium iron phosphate synthesis process, uses an organic compound to carry out two-step carbon treatment to prepare the lithium iron phosphate carbon-coated material with a continuous carbon net inside and a complete carbon layer outside, solves the problem of uneven coating of the carbon material in the lithium iron phosphate, firstly designs a carbon @ iron phosphate composite material with a special structure by using a two-step carbon coating mode, and forms LiFePO through low-temperature reduction4The @ C cathode material positions organic carbon by sanding and liquid-phase external carbon coating, obtains lithium iron phosphate by multi-step carbon coating and reduction reaction, and simultaneously compounds carbon into a matrix material, so that the conductivity of the lithium iron phosphate material is improved; the internal carbon and the external carbon not only provide an in-situ reducing agent for the iron phosphate, but also provide a certain conductive network for the electrode material in the subsequent battery cycle process, thereby effectively improving the point contact and electronic conductivity among particles and between the particles and a current collector, and further improving the electrochemical performance of the material.
Drawings
Fig. 1 is a schematic view of an operation flow of a lithium iron phosphate carbon-coating process in embodiment 1 of the present invention;
fig. 2 is a scanning electron microscope image of the lithium iron phosphate coated with carbon prepared in example 2 of the present invention;
fig. 3 is a scanning electron microscope image of the lithium iron phosphate coated with carbon prepared in embodiment 2 of the present invention at another magnification;
fig. 4 is a voltage-capacity diagram of initial charging and discharging of charging made of the carbon-coated lithium iron phosphate obtained in example 2 of the present invention.
Detailed Description
In order to explain technical contents, achieved objects, and effects of the present invention in detail, the following description is made with reference to the accompanying drawings in combination with the embodiments.
The first embodiment of the invention is as follows: a lithium iron phosphate carbon-coating process, as shown in fig. 1, comprising the steps of:
s1, mixing iron phosphate, lithium carbonate and a first organic carbon source (glucose), adding water, shearing and dispersing to prepare slurry, and sanding solid particles in the slurry;
s2, drying the slurry processed in the step S1 to obtain particles, and carrying out liquid phase coating on the particles by using a second organic carbon source (dopamine);
and S3, reducing and curing the material processed in the step S2 to obtain the carbon-coated lithium iron phosphate.
The second embodiment of the invention is as follows: an iron phosphate carbon-coating process comprises the following steps:
(1) mixing iron phosphate, lithium carbonate and glucose according to the mass ratio of 20:5:2, adding water according to the solid-to-liquid ratio of 25% for shearing and dispersing, and after the slurry is uniformly dispersed, placing the slurry into a sand mill for sand grinding for 30min until the granularity of the slurry of the mixture reaches 0.4 mu m;
(2) spray drying the slurry with qualified particle size to obtain glucose/iron phosphate/lithium carbonate mixed spherical small particles;
(3) and adding the product obtained after the drying treatment into a fresh dopamine hydrochloride solution with the pH value of 8.5 under a magnetic stirring state, continuously stirring for 24 hours under the stirring state, centrifuging, washing and drying the sample, wherein the addition amount of dopamine is 0.5%, and heating the dried powder in an Ar atmosphere furnace at 760 ℃ for 8 hours for carbonization-reduction to obtain the carbon-coated iron phosphate particles.
Scanning electron microscope analysis is carried out on the carbon-coated iron phosphate particles prepared by the operation, and the result is shown in figures 2 and 3, and it can be seen from the figures that the carbon-coated iron phosphate prepared by the scheme of the invention is spherical; the carbon-coated iron phosphate particles prepared by the above operation are subjected to element analysis, and the carbon content of the spherical iron phosphate is determined to be 1.8% (1.5% of glucose and 0.3% of dopamine) after two-step carbon coating.
Taking the lithium iron phosphate prepared by the operation as the positive active material, preparing the lithium iron phosphate into a button cell according to a traditional method, testing the electrochemical performance of the button cell, wherein the first charge-discharge curve is shown in figure 4, and as can be seen from figure 4, the charge-discharge curve of the sample is smooth, which indicates that the charge-discharge platform is stable; the material has the first charge specific capacity of 162.1mAh/g and the first discharge specific capacity of 161.7mAh/g under the multiplying power of 0.1C, and can be predicted to still maintain higher specific capacity in the subsequent electrochemical cycle process. The high first charge-discharge efficiency of the sample shows that the material has certain reversibility, and the material structure is basically kept complete after the first circulation, which is attributed to the good carbon coating effect of the sample material, so that the conductivity of the material is improved, and the internal structure of the material is protected.
The third embodiment of the invention is as follows: an iron phosphate carbon-coating process comprises the following steps:
(1) mixing iron phosphate, lithium carbonate and glucose according to the mass ratio of 102:28:12.5, adding water according to the solid-liquid ratio of 30% for shearing and dispersing, and placing the slurry into a sand mill for sand grinding for 30min after the slurry is uniformly dispersed until the slurry particle size of the mixture reaches 0.6 mu m;
(2) spray drying the slurry with qualified particle size to obtain glucose/iron phosphate/lithium carbonate mixed spherical small particles;
(3) and adding the product obtained after the drying treatment into a fresh dopamine hydrochloride solution with the pH value of 8.5 under a magnetic stirring state, continuously stirring for 24 hours under the stirring state, centrifuging, washing and drying the sample, wherein the addition amount of dopamine is 1%, and heating the dried powder in an Ar atmosphere furnace at 760 ℃ for 8 hours for carbonization reduction to obtain the carbon-coated iron phosphate particles.
In conclusion, according to the lithium iron phosphate carbon-coating process provided by the invention, carbon in-situ reduction is carried out by combining multi-step carbon coating with carbon in-situ reduction of the carbon layer outside the internal carbon network, so that the reducibility is exerted, and the residual carbon position can be determined by the design of the composite material structure. Adding a carbon source to embed lithium in the synthetic process of the lithium iron phosphate materialWhen the carbon is added into the anode material, the conductivity of the material is improved by using the carbon, and the two processes are synchronously carried out, namely the carbon is coated while the carbon participates in the reaction; the invention carries out multi-step multi-layer carbon coating aiming at the problem of poor material conductivity caused by uneven carbon coating in the prior art, can ensure the complete exertion of the reduction effect and can also determine the position of the carbonized carbon through the structural design, and the prepared LiFePO4The @ C material has a carbon network structure with communicated internal and external parts, and the conductivity of the material is improved.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent changes made by using the contents of the present specification and the drawings, or applied directly or indirectly to the related technical fields, are included in the scope of the present invention.
Claims (8)
1. A carbon-coating process for lithium iron phosphate is characterized by comprising the following steps: the method comprises the following steps:
s1, mixing iron phosphate, lithium carbonate and a first organic carbon source to prepare slurry, and grinding solid particles in the slurry;
s2, drying the slurry processed in the step S1 to obtain particles, and carrying out liquid phase coating on the particles by using a second organic carbon source;
s3, reducing and curing the material processed in the step S2 to obtain carbon-coated lithium iron phosphate;
wherein the first organic carbon source is an organic carbon source with reducibility; the second organic carbon source is dopamine; in the step S2, the drying operation is spray drying, and the second organic carbon source liquid phase coating operation is to add the dried particles into a dopamine hydrochloride solution with the pH value of 8-9 and react under a stirring state; the mass ratio of the iron phosphate to the lithium carbonate to the first organic carbon source is 100-102: 25-28: 10 to 12.5; the addition amount of the dopamine is 0.1-1% of the mass of the particles; the first organic carbon source is glucose.
2. The lithium iron phosphate carbon-coating process of claim 1, wherein: the mass ratio of the iron phosphate to the lithium carbonate to the first organic carbon source is 20:5: 2.
3. The lithium iron phosphate carbon-coating process of claim 1, wherein: in the step S1, the particle size of the slurry is controlled to be 0.4-0.6 μm through sanding operation.
4. The lithium iron phosphate carbon-coating process of claim 1, wherein: the addition amount of the dopamine is 0.5 percent of the mass of the granules.
5. The lithium iron phosphate carbon-coating process of claim 1, wherein: the reduction curing operation in the step S3 is to carry out a carbonization reduction reaction in an Ar atmosphere furnace, the reaction time is 6-10 h, and the reaction temperature is 720-780 ℃.
6. A carbon-coated lithium iron phosphate prepared by the process of any one of claims 1 to 5.
7. Use of the carbon-coated lithium iron phosphate of claim 6 in the preparation of a lithium ion battery.
8. A lithium ion battery, characterized by: the lithium ion battery wherein the positive electrode active material comprises the carbon-coated lithium iron phosphate according to claim 6.
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| CN107994229A (en) * | 2017-10-31 | 2018-05-04 | 常州富思通管道有限公司 | A kind of preparation method of novel lithium iron phosphate anode |
| CN109935803B (en) * | 2018-11-28 | 2021-04-27 | 万向一二三股份公司 | Preparation method of lithium iron phosphate cathode material |
| CN109659560B (en) * | 2018-12-26 | 2020-07-07 | 贵州容百锂电材料有限公司 | Lithium cobalt phosphate cathode material for lithium ion battery and preparation method |
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Denomination of invention: The invention relates to a carbon coating process of lithium iron phosphate, a prepared carbon coated lithium iron phosphate and its application Effective date of registration: 20220428 Granted publication date: 20211008 Pledgee: Furong Branch of Changsha Rural Commercial Bank Co.,Ltd. Pledgor: HUNAN YACHENG NEW MATERIAL CO.,LTD. Registration number: Y2022980004964 |
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Denomination of invention: A carbon coating process for lithium iron phosphate, prepared carbon coated lithium iron phosphate and its application Granted publication date: 20211008 Pledgee: Furong Branch of Changsha Rural Commercial Bank Co.,Ltd. Pledgor: Hunan Yacheng New Energy Co.,Ltd. Registration number: Y2024980021661 |