CN114804877B - Pulse current internal heating type medium-temperature graphitized anode material and manufacturing method thereof - Google Patents
Pulse current internal heating type medium-temperature graphitized anode material and manufacturing method thereof Download PDFInfo
- Publication number
- CN114804877B CN114804877B CN202210690493.0A CN202210690493A CN114804877B CN 114804877 B CN114804877 B CN 114804877B CN 202210690493 A CN202210690493 A CN 202210690493A CN 114804877 B CN114804877 B CN 114804877B
- Authority
- CN
- China
- Prior art keywords
- temperature
- pulse current
- preform
- graphitization
- asphalt
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000010438 heat treatment Methods 0.000 title claims abstract description 81
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 17
- 239000010405 anode material Substances 0.000 title claims abstract description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 84
- 238000005087 graphitization Methods 0.000 claims abstract description 49
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000003575 carbonaceous material Substances 0.000 claims abstract description 36
- 239000010426 asphalt Substances 0.000 claims abstract description 32
- 229910052742 iron Inorganic materials 0.000 claims abstract description 30
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 29
- 239000010439 graphite Substances 0.000 claims abstract description 29
- 238000000034 method Methods 0.000 claims abstract description 29
- 238000003763 carbonization Methods 0.000 claims abstract description 24
- 239000002243 precursor Substances 0.000 claims abstract description 23
- 239000000203 mixture Substances 0.000 claims abstract description 22
- 239000011162 core material Substances 0.000 claims abstract description 21
- 238000005056 compaction Methods 0.000 claims abstract description 14
- 239000011331 needle coke Substances 0.000 claims abstract description 13
- 239000000843 powder Substances 0.000 claims abstract description 13
- 239000002131 composite material Substances 0.000 claims abstract description 4
- 238000002425 crystallisation Methods 0.000 claims abstract description 3
- 230000008025 crystallization Effects 0.000 claims abstract description 3
- 239000002994 raw material Substances 0.000 claims description 26
- 229910021383 artificial graphite Inorganic materials 0.000 claims description 20
- 239000011230 binding agent Substances 0.000 claims description 16
- 239000007788 liquid Substances 0.000 claims description 15
- 239000000463 material Substances 0.000 claims description 14
- 230000008569 process Effects 0.000 claims description 12
- 229910052799 carbon Inorganic materials 0.000 claims description 11
- 239000011265 semifinished product Substances 0.000 claims description 9
- 230000000694 effects Effects 0.000 claims description 8
- 229910021382 natural graphite Inorganic materials 0.000 claims description 7
- 239000000047 product Substances 0.000 claims description 7
- 238000005406 washing Methods 0.000 claims description 7
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 6
- 239000002253 acid Substances 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 6
- 238000005260 corrosion Methods 0.000 claims description 6
- 238000001125 extrusion Methods 0.000 claims description 6
- 238000000465 moulding Methods 0.000 claims description 6
- 238000004939 coking Methods 0.000 claims description 5
- 230000007797 corrosion Effects 0.000 claims description 5
- 230000007547 defect Effects 0.000 claims description 5
- 239000007770 graphite material Substances 0.000 claims description 5
- 230000003472 neutralizing effect Effects 0.000 claims description 5
- 150000001721 carbon Chemical class 0.000 claims description 4
- 150000001732 carboxylic acid derivatives Chemical class 0.000 claims description 4
- 238000009792 diffusion process Methods 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 4
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 claims description 4
- 239000011148 porous material Substances 0.000 claims description 4
- 230000009471 action Effects 0.000 claims description 3
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 3
- 239000012752 auxiliary agent Substances 0.000 claims description 3
- 238000000498 ball milling Methods 0.000 claims description 3
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 238000004132 cross linking Methods 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 3
- 230000006698 induction Effects 0.000 claims description 3
- 238000003754 machining Methods 0.000 claims description 3
- 239000012229 microporous material Substances 0.000 claims description 3
- 239000004005 microsphere Substances 0.000 claims description 3
- 238000003801 milling Methods 0.000 claims description 3
- 230000001590 oxidative effect Effects 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 238000001953 recrystallisation Methods 0.000 claims description 3
- 230000009467 reduction Effects 0.000 claims description 3
- 238000007873 sieving Methods 0.000 claims description 3
- 239000007790 solid phase Substances 0.000 claims description 3
- 238000007711 solidification Methods 0.000 claims description 3
- 230000008023 solidification Effects 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 230000002194 synthesizing effect Effects 0.000 claims description 3
- 239000003513 alkali Substances 0.000 claims description 2
- RHZUVFJBSILHOK-UHFFFAOYSA-N anthracen-1-ylmethanolate Chemical compound C1=CC=C2C=C3C(C[O-])=CC=CC3=CC2=C1 RHZUVFJBSILHOK-UHFFFAOYSA-N 0.000 claims description 2
- 239000003830 anthracite Substances 0.000 claims description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 2
- 230000002457 bidirectional effect Effects 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims description 2
- 239000000571 coke Substances 0.000 claims description 2
- 238000001035 drying Methods 0.000 claims description 2
- 230000005669 field effect Effects 0.000 claims description 2
- 230000005389 magnetism Effects 0.000 claims description 2
- 229910052760 oxygen Inorganic materials 0.000 claims description 2
- 239000001301 oxygen Substances 0.000 claims description 2
- 238000000746 purification Methods 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- 238000012546 transfer Methods 0.000 abstract description 3
- 230000006399 behavior Effects 0.000 abstract description 2
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 6
- 229910001416 lithium ion Inorganic materials 0.000 description 6
- 239000007773 negative electrode material Substances 0.000 description 5
- 238000005265 energy consumption Methods 0.000 description 4
- 239000010406 cathode material Substances 0.000 description 3
- 239000011258 core-shell material Substances 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 239000011257 shell material Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000005253 cladding Methods 0.000 description 2
- 238000004146 energy storage Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000003780 insertion Methods 0.000 description 2
- 230000037431 insertion Effects 0.000 description 2
- 238000004321 preservation Methods 0.000 description 2
- 239000005955 Ferric phosphate Substances 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000006183 anode active material Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000002109 crystal growth method Methods 0.000 description 1
- 230000005347 demagnetization Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 229940032958 ferric phosphate Drugs 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 229920005546 furfural resin Polymers 0.000 description 1
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 description 1
- 229910000399 iron(III) phosphate Inorganic materials 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000003446 memory effect Effects 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000009692 water atomization Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
- C04B35/52—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite
- C04B35/522—Graphite
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- 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
-
- 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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
- H01M4/1393—Processes of manufacture of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
-
- 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
- H01M4/58—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
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6562—Heating rate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6567—Treatment time
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/658—Atmosphere during thermal treatment
- C04B2235/6581—Total pressure below 1 atmosphere, e.g. vacuum
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/66—Specific sintering techniques, e.g. centrifugal sintering
- C04B2235/666—Applying a current during sintering, e.g. plasma sintering [SPS], electrical resistance heating or pulse electric current sintering [PECS]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
The invention provides an economic and environment-friendly pulse current internal heating type medium-temperature graphitized anode material with high energy utilization efficiency and high production speed and a manufacturing method thereof, wherein the density of a graphite precursor preform after hot compaction is more than 1.70g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The preform adopts a sheath type composite structure, the outer sleeve adopts a mixture of needle coke and asphalt, and the core material adopts a mixture of carbon materials and iron powder; carrying out vacuum carbonization heat treatment and medium-temperature graphitization on the preform by adopting pulse current internal heating, wherein the pulse current generates instant high temperature and deformation and mass transfer behaviors at a contact interface of powder, and the electromagnetic flow of core material part molten iron in the micro-porous interior of the carbon material and the crystallization function of cooled graphite can be combined and utilized, so that the rapid graphitization is facilitated; the highest graphitization temperature is 1750 to 2150 ℃, and the heating time is less than 5 hours; the d002 surface distance of the obtained anode material is less than 0.3450 nanometers, and the true density is between 2.15 and 2.27g/cm 3 The gram capacity is larger than 345mAh/g, and the first charge and discharge efficiency is larger than 92%.
Description
Technical Field
The invention belongs to the field of lithium ion secondary batteries, and particularly relates to an artificial graphite anode material used in the lithium ion secondary battery.
Background
The lithium ion secondary battery has high energy density and no memory effect, is widely applied to the fields of mobile phones, notebook computers, electric automobiles, energy storage and the like, is large in use amount of power batteries and energy storage batteries serving as mobile energy sources of electric automobiles or electric trucks at present, and has long service life, high energy density, good charge and discharge multiplying power characteristics and low manufacturing cost.
The graphite cathode has high specific capacity, low reduction potential, good electrochemical reversibility, low volume expansion rate, high electronic conductivity and wide raw material source, and is a main-stream cathode material of the current lithium ion secondary battery.
Commercial negative electrode materials mainly include artificial graphite and natural graphite. The natural graphite has the advantages of low cost and high compaction density, and has the main defects of rough surface of natural graphite powder, large specific surface area, and more lithium sources wasted in reaction in the process of forming an SEI film on the surface of the anode active material during the first charge and discharge, so that the first charge and discharge efficiency is low; the natural graphite has obvious multicrystal anisotropy, the volume expansion of the cathode materials is not easy to cancel each other during charging/discharging, the battery is easy to bulge, the interval fluctuation of the electrode group is large, the cycle life of the battery is reduced rapidly, in addition, the anisotropy of the multicrystal also causes that the insertion/extraction of lithium ions can only be carried out from certain end faces of the graphite powder multicrystal, the effective insertion/extraction area is small, and the charge/discharge multiplying power characteristic of the battery is poor.
Currently, the main stream of industry is to use artificial graphite as a negative electrode active material, such as artificial graphite which is subjected to high-temperature graphitization treatment at 2800-3100 ℃ by using mesophase carbon microspheres or calcined needle coke, wherein the artificial graphite polycrystal is basically isotropic, the powder surface is smooth, the specific surface area is small, the initial efficiency of the battery is high, the irreversible capacity is low, the cycle life is long, the multiplying power characteristic is good, and the defects are that the processing period of the high-temperature graphitization procedure of the artificial graphite is long and the energy consumption is high; the high-temperature graphitization temperature of the existing artificial graphite is up to 2800-3100 ℃, the graphitization degree of the graphite precursor is improved mainly by utilizing the thermal diffusion and the re-participation of carbon atoms in the part of the high Wen Xiafei crystal area, the raw material powder of the graphite precursor is basically loosely arranged in a graphite crucible in the traditional Acheson graphitization furnace, and the tap density is less than 1.10g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The carbon resistance particles are added between the graphite crucibles, 70-80% of heating heat is used for the process auxiliary materials and external heat preservation materials, the heating and heat preservation time is about 15 days, the cooling time is about 10 days, the processing period of one furnace is close to one month, the whole energy consumption is high, the effective utilization rate of energy sources is low, the processing period is long, the fund occupation period is long, and the method becomes a bottleneck link for reducing the cost of the artificial graphite.
In order to reduce the cost of artificial graphite, the mainstream improvement in the aspect of raw materials is to adopt a coated product with a core-shell structure, such as a natural graphite powder or needle coke powder is coated and modified by adopting graphite precursors such as asphalt or furfural resin, and then high-temperature carbonization and high-temperature graphitization treatment are carried out to prepare the artificial graphite, so that the coating process is complex, the product manufacturing period is long, and the overall energy consumption is still higher.
The invention is provided for overcoming the defects and shortcomings of the existing artificial graphite cathode material manufacturing method, especially for renovating the traditional high-temperature graphitization process of the artificial graphite material, reducing the production cost and the production period.
Disclosure of Invention
The invention provides an economical, environment-friendly, high energy utilization efficiency, high production speed and good product consistency pulse current internal heating type medium temperature graphitized anode material and a manufacturing method thereof, which are characterized in that the density of a preformed blank of a graphitized precursor after hot compaction is more than 1.70g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the Carrying out vacuum carbonization heat treatment and medium-temperature graphitization on the preform by adopting pulse current internal heating, wherein the highest temperature of graphitization is 1750 to 2150 ℃, and the effective heating time of the temperature interval is less than 5 hours; the d002 surface spacing of the negative electrode material obtained after graphitization is less than 0.3450 nanometers, and the true density is between 2.15 and 2.27g/cm 3 The gram capacity is larger than 345mAh/g, and the first charge and discharge efficiency is larger than 92%; the manufacturing method of the pulse current internal heating type medium temperature graphitized anode material mainly comprises the following four main steps:
step1, three main raw materials are prepared: graphite precursor fine powder (G1), wherein the graphite precursor raw material mainly comprises one or a plurality of compositions of needle coke (G1-1), coke (G1-2), anthracite (G1-3), mesophase carbon microspheres (G1-4) and natural graphite (G1-5); crushing and grading a graphite precursor raw material, carrying out acid washing and/or alkali washing purification according to ash content, neutralizing and drying, wherein ash content is less than 0.3%, and granularity is controlled to be between 6 and 18 microns, and D95 is less than 30 microns; the high-temperature binder adopts asphalt (HA 2) and comprises one or a combination of low-softening-point asphalt (LQ-1) and high-softening-point asphalt (LQ-2), wherein the softening point of (LQ-1) is between 100 and 200 ℃, the coking value is between 50 and 70 percent, the weight percentage of (LQ-1) in the two asphalts is between 0 and 35 percent, and the rest is (LQ-2); (LQ-2) having a softening point of 200 to 285 ℃ and a coking value of 55% to 80%; iron powder (Fe 3) is used as a medium-temperature graphitization auxiliary agent, the carbon content in the iron powder is less than 4wt.%, and the granularity is between 200 meshes and 800 meshes.
Step2, preparing a preform (S/C) by hot press molding or extrusion molding, wherein the preform adopts a sheath type composite structure (S/C) of a core material (C) wrapped by a sheath (S); the outer sleeve (S) adopts a mixture (G1-1/HA 2) of needle coke (G1-1) and high-temperature binder asphalt (HA 2) as raw materials, wherein the high-temperature binder asphalt (HA 2) accounts for 25-30% of the two carbon materials in percentage by weight, and the rest is (G1-1); the core material (C) adopts a mixture of three main raw materials (G1), (HA 2) and (Fe 3), wherein the true volume percentage of the (Fe 3) and the core material is 15-30vol.%, and the weight percentage of the (HA-2) and the core material (G1) is 25-30 wt.%; when the core material (C) and the jacket/core material combination (S/C) are formed by hot press molding or extrusion, the compaction density of the jacket is controlled to be 1.70-2.00 g/cm by adopting a temperature range of 10-330 ℃ above the softening point of asphalt and adopting a pressure of 5-25 MPa 3 The method comprises the steps of carrying out a first treatment on the surface of the The contact surface part of the preform and the electrode is thermally pressed and sealed by taking a mixture (G1-1/HA 2) of needle coke (G1-1) and high-temperature binder asphalt (HA 2) as raw materials, wherein the high-temperature binder asphalt (HA 2) accounts for 25 to 30 percent of the weight of the two, the thickness of the contact surface material of the electrode after thermal compaction is 25 to 80mm, and the compaction density is controlled to be 1.70 to 2.00G/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The cross-sectional shape of the preform (S/C) is circular or square; the cross-sectional area of the sleeve (S) is between 0 and 35% of the overall cross-sectional area of the preform (S/C).
Step3, pulse current internal heating type vacuum carbonization heat treatment and medium temperature graphitization of the preform (S/C), putting the preform (S/C) workpiece into a pulse current internal heating type vacuum heating furnace when the preform (S/C) workpiece is in a thermal state of more than 150 ℃, vacuumizing a sealed furnace cover to be better than 200Pa, and applying at least more than 0.15MPa pressure between a graphite electrode pressure head and the preform (S/C) workpiece and compacting the graphite electrode pressure head and the preform (S/C) workpiece in a non-electrified state; then pulse current internal heating type vacuum carbonization heat treatment is carried outProcessing in two sequences of rational and medium-temperature graphitization, wherein the average current area density of the applied pulse current is 1-50A/cm 2 The duty ratio of the pulse current is 12:1 to 1:6, the frequency of the pulse current is 1 to 30Hz, and the pulse current can be unidirectional direct current or bidirectional alternating direct current; after the precursor is subjected to the previous preheating and compacting process, point contact can be formed between the powder bodies of the graphite precursor, and when the powder bodies are directly heated by the pulse current mode, instant high-temperature deformation and mass transfer behaviors can be generated at the contact interface of the powder bodies by utilizing the contact resistance heat of the powder bodies, so that the rapid graphitization is facilitated; (1) Vacuum carbonization heat treatment, heating the material at a temperature range of 150-450 ℃ at a heating rate of 5-50 ℃/h, preserving heat for at least 1 hour after the temperature of the material reaches 450 ℃, performing heat crosslinking treatment, and then continuing vacuum carbonization heat treatment at a temperature range of 450-850 ℃ at a heating rate of 50-100 ℃/h, wherein the temperature is preserved for at least 1 hour in a temperature range of 750-850 ℃; through the vacuum carbonization heat treatment, the preformed blank (S/C) forms a microstructure mainly comprising a three-dimensional penetrating microporous material carbon material with better electric conductivity, and the iron powder is dispersed and distributed in the micropores of the core material part carbon material; (2) Continuously electrifying the preform (S/C) subjected to vacuum carbonization heat treatment by adopting pulse current to perform internal heating type medium temperature graphitization, heating at a temperature range of 850-1450 ℃ at a heating rate of 100-300 ℃/h, heating at a temperature range of 1450-2150 ℃ at a heating rate of 50-150 ℃/h, preserving heat for at least 1-5 hours at a temperature range of 1750-2150 ℃, stopping heating, and cooling to 330 ℃ and then discharging; at high temperature of above 1350 ℃, the iron powder in the micro-porous interior of the carbon material of the core material part of the preform is melted, under the capillary action of the micro-porous pores of the carbon material, the micro-magnetic field effect formed when pulse current flows through the three-dimensional framework of the carbon material is combined, the molten iron generates endogenous electromagnetic stirring flow in the micro-porous pores of the carbon material, the flow of the molten iron realizes the mutual diffusion of iron and carbon elements in the carbon material at high temperature, and the molten iron carries out micro-melting corrosion on the micro-porous surface of the carbon material to changeThe specific surface area and the surface defect of the carbon material are improved, the flowing of molten iron also forms an internal friction effect on the carbon material, microscopic shearing force is formed in polycrystal of the carbon material, carbon atoms in the polycrystal participate in the recrystallization process, and the auxiliary graphitization effect of the molten iron under the induction of stress is achieved; in the solidification temperature range from the subsequent temperature reduction to about 1250 ℃, the supersaturated carbon dissolved in the iron can be diffused and separated out, and a novel graphite coating shell layer with high isotropy grows on the inner surface of the micro-porous of the carbon material in a crystallization manner, so that the anisotropic effect and the power characteristic of the carbon material are improved.
Step4, chemically corroding and dissolving iron in the semi-finished product mixture, machining or crushing the cooled semi-finished product, adopting mixed acid liquor of phosphoric acid and organic carboxylic acid as corrosive liquid, sieving the crushed product of the semi-finished product with a 150-mesh sieve, immersing in the corrosive liquid, simultaneously charging oxygen or compressed air into the corrosive liquid, chemically corroding and dissolving the iron in the mixture under an oxidizing atmosphere, filtering a solid-liquid mixture after the iron is completely dissolved, washing with water and neutralizing, finely ball-milling or air-flow milling the collected solid-phase graphite material, grading the granularity, and removing the magnetism to obtain the artificial graphite anode material; the corrosion residual liquid is used as a raw material for synthesizing lithium iron phosphate.
In order to balance the speed and degree of graphitization and reduce radiation loss at high temperature, the highest temperature of medium temperature graphitization is more preferably 1900-2000 ℃, the effective heating time in the temperature range is 2-3 hours, the d002 face spacing after graphitization is less than 0.3390 nanometers, and the true density is 2.20-2.27g/cm 3 The gram capacity is more than 355mAh/g, and the first charge and discharge efficiency is more than 93%.
In view of the fact that the saturated solubility of carbon in molten iron is higher than 5.5wt.% at a high temperature of 1650-2150 ℃, supersaturated carbon dissolved in iron can be separated out in the cooling solidification process, a novel graphite layer can be grown on the micropore surface of a carbon material by means of a crystal growth method, the isotropy characteristic of a graphite precursor polycrystal can be improved, compared with a traditional manufacturing method of artificial graphite by mechanical cladding/medium-temperature carbonization and high-temperature graphitization, the novel cladding type core-shell structure which is formed by naturally attaching and growing the supersaturated carbon separated out and recrystallized from molten iron is realized by the method, the interface strength between the core-shell is high, the shell of the artificial graphite negative electrode material powder is not easy to be fed by pressure in the compaction process of preparing a negative electrode plate, the prepared battery has high capacity, high first charge-discharge efficiency, good multiplying power characteristic and long cycle life.
The method for preparing the intermediate-temperature graphitization assisted by the molten iron skillfully utilizes the function of asphalt as a high-temperature binder, and connects graphite precursors into a complete three-dimensional penetrating microporous material after vacuum carbonization.
The invention uses the medium high temperature range of 1750-2150 ℃ to graphitize, can greatly reduce the radiant heat, combines electromagnetic stirring of molten iron to form internal friction on the carbon material, and forms microscopic shear stress in the carbon material, thereby having the recrystallization characteristic under stress induction, being capable of realizing effective improvement of graphitization degree at the medium high temperature of 1750-2150 ℃ without depending on the traditional thermal diffusion type high temperature graphitization at 2800-3150 ℃, and preparing the artificial graphite anode material for lithium ion batteries; the invention adopts a pulse current internal heating type direct heating mode under a vacuum condition, the heat energy utilization efficiency is far higher than that of the traditional high-temperature graphitization furnace, the invention adopts a precursor with high compaction density, the effective specific surface area of a heated workpiece is smaller, and a large amount of heat is not wasted on a furnace shell material and a crucible material and a resistor material which occupy a larger volume of the traditional graphitization furnace; the method comprehensively reduces the heating time of graphitization, reduces the energy consumption, and can obtain the artificial graphite anode material with high graphitization degree and good isotropy; the carbon material is in vacuum during medium-temperature graphitization, which is favorable for the migration and mass transfer of volatile matters, and the pure artificial graphite material is easy to obtain.
The byproduct ferric phosphate obtained after corrosion is used as the raw material for producing the lithium iron phosphate, the production process basically has no solid waste, and the process is environment-friendly.
Detailed Description
The following examples are given by taking the technical scheme and spirit of the present invention as a premise to implement the detailed implementation and specific process, but not limiting the scope of the present invention, and all the technical schemes obtained by adopting alternative or equivalent transformation forms, such as proper adjustment of carbon content in iron plates, or the like, or that the iron powder contains a certain amount of alloy elements such as Si, ce, mg, mn, etc. are understood to fall within the scope of the present invention.
Example 1 the density of the preform of graphitized precursor after hot compaction is in the range of 1.80 to 1.90g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the Carrying out vacuum carbonization heat treatment and medium-temperature graphitization on the preform by adopting pulse current internal heating, wherein the highest temperature of graphitization is 1900-2000 ℃, and the effective heating time of the temperature interval is 3 hours; the d002 surface distance of the negative electrode material obtained after graphitization is 0.3383 nanometers, and the true density is 2.21 to 2.25g/cm 3 The gram capacity is larger than 360mAh/g, and the first charge and discharge efficiency is 94.3%; the manufacturing method of the pulse current internal heating type medium temperature graphitized anode material mainly comprises the following four main steps:
stepl, three main raw materials are prepared: fine graphite precursor powder (G1), wherein needle coke (G1-1) is adopted as a raw material of the graphite precursor; crushing and grading the graphite precursor raw material, wherein ash content is less than 0.1%, and granularity is controlled to be between 8 and 12 microns, and D95 is less than 20 microns; the high-temperature binder adopts asphalt (HA 2), and adopts high-softening-point asphalt (LQ-2), wherein the softening point of the (LQ-2) is 240-255 ℃, and the coking value is 73-78%; iron powder (Fe 3) is used as a medium-temperature graphitization auxiliary agent, the carbon content in the iron powder is less than 1wt.%, the granularity is between 325 and 500 meshes, and the iron powder manufactured by a water atomization process is selected.
Step2, preparing a preform (S/C) by hot press molding or extrusion molding, wherein the preform adopts a sheath type composite structure (S/C) with a core material (C) wrapped by a sheath (S)) The method comprises the steps of carrying out a first treatment on the surface of the The outer sleeve (S) adopts a mixture (G1-1/HA 2) of needle coke (G1-1) and high-temperature binder asphalt (HA 2) as raw materials, wherein the high-temperature binder asphalt (HA 2) accounts for 27 percent of the two carbon materials by weight; the core material (C) adopts a mixture of three main raw materials (G1), (HA 2) and (Fe 3), wherein the true volume percentage of the (Fe 3) and the core material (C) is 25.6vol percent, and the weight percentage of the (HA-2) and the (G1) is 27wt percent; when the core material (C) and the jacket/core material combination (S/C) are formed by hot press molding or extrusion, the material temperature is controlled to be 280-295 ℃, the compaction density of the jacket is controlled to be 1.80-1.90g/cm by adopting the pressure of 10-15 MPa 3 The method comprises the steps of carrying out a first treatment on the surface of the The contact surface part of the preform and the electrode is thermally pressed and sealed by taking a mixture (G1-1/HA 2) of needle coke (G1-1) and high-temperature binder asphalt (HA 2) as raw materials, wherein the high-temperature binder asphalt (HA 2) accounts for 27 percent of the weight of the two, the thickness of the contact surface material of the electrode after being thermally pressed is 50-55mm, and the compaction density is controlled to be 1.80-1.90G/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The cross-sectional shape of the preform (S/C) is circular; the cross-sectional area of the jacket (S) is 20% of the overall cross-sectional area of the preform (S/C).
Step3, pulse current internal heating type vacuum carbonization heat treatment and medium temperature graphitization of the preform (S/C), putting the preform (S/C) workpiece into a pulse current internal heating type vacuum heating furnace when the preform (S/C) workpiece is in a thermal state above 230 ℃, vacuumizing a sealed furnace cover to be better than 100Pa, and applying a pressure of 0.35MPa between a graphite electrode pressure head and the preform (S/C) workpiece in a non-electrified state and compacting; then pulse current internal heating type vacuum carbonization heat treatment and medium temperature graphitization are carried out, and the average current area density of the applied pulse current is between 2 and 25A/cm 2 The duty ratio of the pulse current is 3:1, the frequency of the pulse current is 16Hz, and the pulse current adopts unidirectional direct current; (1) Vacuum carbonization heat treatment, heating the material at a temperature range of 230-450 ℃ according to a heating rate of 9 ℃/h, preserving heat for 2 hours after the temperature of the material reaches 450 ℃, performing heat crosslinking treatment, and then continuing vacuum carbonization heat treatment at a temperature range of 450-850 ℃ according to a heating rate of 50 ℃/h, wherein the temperature is preserved for 1 hour at a temperature range of 800-850 ℃; (2) Medium-temperature graphitization treatmentContinuously electrifying the preform (S/C) subjected to vacuum carbonization heat treatment by adopting pulse current to carry out internal heating type medium-temperature graphitization, heating at the temperature interval of 850-1950 ℃ according to the heating rate of 150 ℃/h, preserving heat for 3 hours at the temperature interval of 1900-1950 ℃, stopping heating, cooling to below 800 ℃ along with a furnace, introducing nitrogen, cooling to 330 ℃, and then maintaining for 1 hour and discharging.
Step4, chemically corroding and dissolving iron in the semi-finished product mixture, machining or crushing the cooled semi-finished product, adopting mixed acid liquor of phosphoric acid and organic carboxylic acid, wherein the ratio of the mixed acid liquor to the organic carboxylic acid is 1:0.25, sieving the crushed product of the semi-finished product by a 200-mesh sieve, immersing the crushed product in the corrosive liquid according to the solid-to-liquid ratio of 1:20, simultaneously filling compressed air into the corrosive liquid, chemically corroding and dissolving the iron in the mixture under the oxidizing atmosphere, filtering the solid-liquid mixture after the iron is completely dissolved, washing and neutralizing, carrying out fine ball milling or air flow milling on the collected solid-phase graphite material, grading the granularity, and carrying out demagnetization to obtain the artificial graphite anode material; the corrosion residual liquid is used as a raw material for synthesizing lithium iron phosphate.
Claims (2)
1. The pulse current internal heating type medium temperature graphitized anode material manufacturing method is characterized in that the density of a preformed blank of a graphitized precursor after hot compaction is more than 1.70g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the Vacuum carbonization heat treatment and medium-temperature graphitization are carried out on the preform by adopting pulse current internal heating, the highest temperature of graphitization is between 1750 and 2150 ℃, the effective heating time of the temperature interval is less than 5 hours, the d002 face spacing after graphitization is less than 0.3450 nanometers, and the true density is between 2.15 and 2.27g/cm 3 The gram capacity is larger than 345mAh/g, and the first charge and discharge efficiency is larger than 92%; the manufacturing method of the pulse current internal heating type medium temperature graphitized anode material mainly comprises the following four main steps:
step1, three main raw materials are prepared: graphite precursor fine powder (G1), wherein the graphite precursor raw material mainly comprises one or a plurality of compositions of needle coke (G1-1), coke (G1-2), anthracite (G1-3), mesophase carbon microspheres (G1-4) and natural graphite (G1-5); crushing and grading a graphite precursor raw material, carrying out acid washing and/or alkali washing purification according to ash content, neutralizing and drying, wherein ash content is less than 0.3%, and granularity is controlled to be between 6 and 18 microns, and D95 is less than 30 microns; the high-temperature binder adopts asphalt (HA 2), and comprises high-softening-point asphalt (LQ-2) and low-softening-point asphalt (LQ-1), wherein the softening point of the low-softening-point asphalt (LQ-1) is between 100 and 200 ℃, the coking value is between 50 and 70%, the weight percentage of the low-softening-point asphalt (LQ-1) in the two asphalts is between 0 and 35%, the zero point is not included, and the rest is the high-softening-point asphalt (LQ-2); the softening point of the high softening point asphalt (LQ-2) is 200 to 285 ℃, and the coking value is 55 to 80 percent; iron powder (Fe 3) is used as a medium-temperature graphitization auxiliary agent, the carbon content in the iron powder is less than 4 weight percent, and the granularity is between 200 meshes and 800 meshes;
step2, preparing a preform (S/C) by hot press molding or extrusion molding, wherein the preform (S/C) adopts a sheath type composite structure in which a core material (C) is wrapped by a sheath (S); the outer sleeve (S) adopts a mixture (G1-1/HA 2) of two carbon materials of needle coke (G1-1) and high-temperature binder asphalt (HA 2) as raw materials, wherein the high-temperature binder asphalt (HA 2) accounts for 25-30% of the two carbon materials by weight percent, and the rest is the needle coke (G1-1); the core material (C) adopts a mixture of three main raw materials, namely graphite precursor fine powder (G1), asphalt (HA 2) and iron powder (Fe 3), wherein the iron powder (Fe 3) accounts for 15-30 vol% of the three main raw materials, and the asphalt (HA 2) accounts for 25-30wt% of both the graphite precursor fine powder (G1) and the asphalt (HA 2); when the core material (C) and the jacket/core material combination are formed by hot press molding or extrusion, the temperature range of 10 ℃ to 330 ℃ above the softening point of asphalt is adopted, the pressure of 5 to 25MPa is adopted, and the compaction density of the jacket is controlled to be 1.70 to 2.00g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The contact surface part of the preform and the electrode is thermally pressed and sealed by taking a mixture (G1-1/HA 2) of needle coke (G1-1) and high-temperature binder asphalt (HA 2) as raw materials, wherein the high-temperature binder asphalt (HA 2) accounts for 25 to 30 percent of the weight of the two, the thickness of the contact surface material of the electrode after being thermally compacted is 25 to 80mm, and the compaction density is 1.70 to 2.00G/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The cross-sectional shape of the preform (S/C) is circular or square; the sleeve (S) having a cross-sectional area of 0 to 0% of the overall cross-sectional area of the preform (S/C)35%; step3, pulse current internal heating type vacuum carbonization heat treatment and medium temperature graphitization of the preform (S/C), putting the preform (S/C) workpiece into a pulse current internal heating type vacuum heating furnace when the preform (S/C) workpiece is in a thermal state of more than 150 ℃, vacuumizing a sealed furnace cover to be better than 200Pa, and applying and compacting pressure of more than or equal to 0.15MPa between a graphite electrode pressure head and the preform (S/C) workpiece in a non-electrified state; then pulse current internal heating type vacuum carbonization heat treatment and medium temperature graphitization are carried out, and the average current area density of the applied pulse current is 1 to 50A/cm 2 The duty ratio of the pulse current is between 12:1 and 1:6, the frequency of the pulse current is between 1 and 30Hz, and the pulse current is unidirectional direct current or bidirectional alternating direct current; (1) Vacuum carbonization heat treatment, heating the material at a temperature range of 150-450 ℃ at a heating rate of 5-50 ℃/h, preserving heat for at least 1 hour after the temperature of the material reaches 450 ℃, performing heat crosslinking treatment, and then continuing vacuum carbonization heat treatment at a temperature range of 450-850 ℃ at a heating rate of 50-100 ℃/h, wherein the temperature is preserved for at least 1 hour in a temperature range of 750-850 ℃; through the vacuum carbonization heat treatment, the preformed blank (S/C) forms a microstructure mainly comprising a three-dimensional penetrating microporous material carbon material with better electric conductivity, and the iron powder is dispersed and distributed in the micropores of the core material part carbon material; (2) Continuously electrifying the preform (S/C) subjected to vacuum carbonization heat treatment by adopting pulse current to perform internal heating type medium temperature graphitization, heating at the temperature interval of 850-1450 ℃ at the heating rate of 100-300 ℃/h, heating at the temperature interval of 1450-2150 ℃ at the heating rate of 50-150 ℃/h, preserving heat for 1-less than 5 hours at the temperature interval of 1750-2150 ℃, stopping heating, and cooling to 330 ℃ and then discharging; at the high temperature of 1400 ℃ and above, the iron powder in the micro-porous interior of the carbon material of the core material part of the preform is melted, under the capillary action of the micro-porous pores of the carbon material, the micro-magnetic field effect formed when pulse current flows through the three-dimensional framework of the carbon material is combined, the molten iron generates endogenous electromagnetic stirring flow in the micro-porous pores of the carbon material, and the flow of the molten iron realizes the mutual action of the iron and carbon elements in the carbon material at the high temperatureThe diffusion, the micro-corrosion of molten iron on the micro-porous surface of the carbon material, the effect of improving the specific surface area and surface defects of the carbon material is achieved, the flow of the molten iron also forms an internal friction effect on the carbon material, a micro shear force is formed in the polycrystal of the carbon material, carbon atoms in the polycrystalline body are accelerated to participate in the recrystallization process, and the auxiliary graphitization effect of the molten iron under stress induction is achieved; in the solidification temperature range from the subsequent temperature reduction to 1250 ℃, the supersaturated carbon dissolved in the iron can be diffused and separated out, and a graphite coating shell layer with high isotropy grows on the micro-porous inner surface of the carbon material in a crystallization way, so that the anisotropic effect and the power characteristic effect of the carbon material are improved;
step4, chemically corroding and dissolving iron in the semi-finished product mixture, machining or crushing the cooled semi-finished product, adopting mixed acid liquor of phosphoric acid and organic carboxylic acid as corrosive liquid, sieving the crushed product of the semi-finished product with a 150-mesh sieve, immersing in the corrosive liquid, simultaneously charging oxygen or compressed air into the corrosive liquid, chemically corroding and dissolving the iron in the mixture under an oxidizing atmosphere, filtering a solid-liquid mixture after the iron is completely dissolved, washing with water and neutralizing, finely ball-milling or air-flow milling the collected solid-phase graphite material, grading the granularity, and removing the magnetism to obtain the artificial graphite anode material; the corrosion residual liquid is used as a raw material for synthesizing lithium iron phosphate.
2. The process according to claim 1, wherein the medium temperature graphitization has a maximum temperature of 1900-2000℃and an effective heating time of 2-3 hours, the d002 face pitch after graphitization is less than 0.3390 nm, and the true density is 2.20-2.27g/cm 3 The gram capacity is more than 355mAh/g, and the first charge and discharge efficiency is more than 93%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210690493.0A CN114804877B (en) | 2022-05-19 | 2022-05-19 | Pulse current internal heating type medium-temperature graphitized anode material and manufacturing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210690493.0A CN114804877B (en) | 2022-05-19 | 2022-05-19 | Pulse current internal heating type medium-temperature graphitized anode material and manufacturing method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114804877A CN114804877A (en) | 2022-07-29 |
| CN114804877B true CN114804877B (en) | 2024-01-23 |
Family
ID=82521310
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210690493.0A Active CN114804877B (en) | 2022-05-19 | 2022-05-19 | Pulse current internal heating type medium-temperature graphitized anode material and manufacturing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114804877B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3309326A (en) * | 1963-02-22 | 1967-03-14 | United Coke & Chemicals Compan | Production of electrically conducting carbon |
| CN102522561A (en) * | 2011-12-21 | 2012-06-27 | 清华大学 | Lithium ion battery cathode material and preparation method thereof |
| CN104860678A (en) * | 2015-04-29 | 2015-08-26 | 萝北奥星新材料有限公司 | Method for producing ultra-high power graphite electrode through natural graphite |
| CN105886727A (en) * | 2016-05-05 | 2016-08-24 | 北京科技大学 | Method for promoting graphitization of hypoeutectoid steel through adopting pulse current |
| CN106486670A (en) * | 2015-11-17 | 2017-03-08 | 上海杉杉科技有限公司 | A kind of method that mesophase pitch Jiao prepares lithium cell cathode material |
| CN109860524A (en) * | 2017-11-30 | 2019-06-07 | 宝武炭材料科技有限公司 | A kind of method of solid asphalt low temperature cladding preparation negative electrode material |
| CN110668819A (en) * | 2019-10-28 | 2020-01-10 | 焦作市中州炭素有限责任公司 | Short-flow high-power graphite electrode and production process |
-
2022
- 2022-05-19 CN CN202210690493.0A patent/CN114804877B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3309326A (en) * | 1963-02-22 | 1967-03-14 | United Coke & Chemicals Compan | Production of electrically conducting carbon |
| CN102522561A (en) * | 2011-12-21 | 2012-06-27 | 清华大学 | Lithium ion battery cathode material and preparation method thereof |
| CN104860678A (en) * | 2015-04-29 | 2015-08-26 | 萝北奥星新材料有限公司 | Method for producing ultra-high power graphite electrode through natural graphite |
| CN106486670A (en) * | 2015-11-17 | 2017-03-08 | 上海杉杉科技有限公司 | A kind of method that mesophase pitch Jiao prepares lithium cell cathode material |
| CN105886727A (en) * | 2016-05-05 | 2016-08-24 | 北京科技大学 | Method for promoting graphitization of hypoeutectoid steel through adopting pulse current |
| CN109860524A (en) * | 2017-11-30 | 2019-06-07 | 宝武炭材料科技有限公司 | A kind of method of solid asphalt low temperature cladding preparation negative electrode material |
| CN110668819A (en) * | 2019-10-28 | 2020-01-10 | 焦作市中州炭素有限责任公司 | Short-flow high-power graphite electrode and production process |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114804877A (en) | 2022-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9666863B2 (en) | Nano silicon-carbon composite material and preparation method thereof | |
| CN109273680B (en) | Porous silicon-carbon negative electrode material, preparation method thereof and lithium ion battery | |
| CN101710617B (en) | High-energy silicon-carbon composite negative electrode material for lithium ion battery and manufacturing process thereof | |
| CN107342411B (en) | Preparation method of graphene-silicon-carbon lithium ion battery negative electrode material | |
| CN107611416B (en) | Silicon-carbon composite material, preparation method and application thereof | |
| CN106169582A (en) | A kind of natural pin Jiao's composite graphite negative electrode material production method | |
| CN114620707A (en) | Preparation method of long-cycle lithium ion battery cathode material | |
| CN115124028B (en) | Artificial graphite negative electrode material inoculated with high-low temperature molten iron and manufacturing device thereof | |
| CN115676815A (en) | Manufacturing device and method for molten iron inoculated artificial graphite cathode material | |
| CN111740110A (en) | Composite negative electrode material, preparation method thereof and lithium ion battery | |
| CN107749478A (en) | A kind of LiMn2O4 ternary power lithium ion battery | |
| CN107749465A (en) | A kind of LiFePO4 NCM ternary material power lithium-ion batteries | |
| CN115028164B (en) | Iron water inoculated artificial graphite negative electrode material and manufacturing method thereof | |
| CN114804877B (en) | Pulse current internal heating type medium-temperature graphitized anode material and manufacturing method thereof | |
| CN114804095B (en) | Graphite negative electrode active material prepared from spheroidized graphite micropowder waste, and preparation method and application thereof | |
| CN114804091B (en) | Molten iron-assisted graphitized artificial graphite negative electrode material and manufacturing method thereof | |
| CN115207349A (en) | Graphite negative electrode material and preparation method and application thereof | |
| CN115133012A (en) | Coral-shaped nano silicon powder for lithium ion battery negative electrode, negative electrode material and preparation method | |
| CN107749477A (en) | A kind of nickel cobalt manganese NCM ternary material power lithium-ion batteries | |
| CN107749463A (en) | A kind of LiMn2O4 cobalt acid lithium power lithium-ion battery | |
| CN110697699A (en) | Preparation method of high-capacity lithium ion battery graphite negative electrode material | |
| CN115611275B (en) | Artificial graphite negative electrode active material, preparation and application thereof | |
| CN115536019B (en) | Artificial graphite material, preparation thereof and application thereof in lithium secondary battery | |
| CN107785544A (en) | A kind of nickel cobalt aluminium NCA ternary material power lithium-ion batteries | |
| CN114620719A (en) | Intermediate-temperature graphitized artificial graphite negative electrode material and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20221010 Address after: 103, Building R2-B, Gaoxin Industrial Village, No. 020, Gaoxin South 7th Road, Gaoxin District Community, Yuehai Street, Nanshan District, Shenzhen, Guangdong 518000 Applicant after: Shenzhen Gangyu Carbon Crystal Technology Co.,Ltd. Address before: 100101 1084, area C, jiamingyuan, No. 86, Beiyuan Road, Chaoyang District, Beijing Applicant before: Li Xin |
|
| TA01 | Transfer of patent application right | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |