CN116936735A - Dry electrode film with low binder content, preparation method and application thereof - Google Patents
Dry electrode film with low binder content, preparation method and application thereof Download PDFInfo
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- CN116936735A CN116936735A CN202310865134.9A CN202310865134A CN116936735A CN 116936735 A CN116936735 A CN 116936735A CN 202310865134 A CN202310865134 A CN 202310865134A CN 116936735 A CN116936735 A CN 116936735A
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- 239000006258 conductive agent Substances 0.000 claims abstract description 43
- 239000007772 electrode material Substances 0.000 claims abstract description 41
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 17
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- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 claims description 13
- 239000001768 carboxy methyl cellulose Substances 0.000 claims description 13
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 7
- 239000011164 primary particle Substances 0.000 claims description 7
- 239000011163 secondary particle Substances 0.000 claims description 7
- 239000011246 composite particle Substances 0.000 claims description 5
- 238000012216 screening Methods 0.000 claims description 4
- IXPNQXFRVYWDDI-UHFFFAOYSA-N 1-methyl-2,4-dioxo-1,3-diazinane-5-carboximidamide Chemical compound CN1CC(C(N)=N)C(=O)NC1=O IXPNQXFRVYWDDI-UHFFFAOYSA-N 0.000 claims description 3
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 3
- 239000002033 PVDF binder Substances 0.000 claims description 3
- 239000004698 Polyethylene Substances 0.000 claims description 3
- 239000004642 Polyimide Substances 0.000 claims description 3
- 239000004743 Polypropylene Substances 0.000 claims description 3
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- 239000004917 carbon fiber Substances 0.000 claims description 3
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- 230000007797 corrosion Effects 0.000 claims description 3
- 238000005260 corrosion Methods 0.000 claims description 3
- 239000004584 polyacrylic acid Substances 0.000 claims description 3
- 229920002239 polyacrylonitrile Polymers 0.000 claims description 3
- 229920000573 polyethylene Polymers 0.000 claims description 3
- 229920001721 polyimide Polymers 0.000 claims description 3
- 229920001155 polypropylene Polymers 0.000 claims description 3
- 229920002635 polyurethane Polymers 0.000 claims description 3
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- 229920002981 polyvinylidene fluoride Polymers 0.000 claims description 3
- 229910052708 sodium Inorganic materials 0.000 claims description 3
- 239000011734 sodium Substances 0.000 claims description 3
- 239000000661 sodium alginate Substances 0.000 claims description 3
- 235000010413 sodium alginate Nutrition 0.000 claims description 3
- 229940005550 sodium alginate Drugs 0.000 claims description 3
- 229920003048 styrene butadiene rubber Polymers 0.000 claims description 3
- 239000011883 electrode binding agent Substances 0.000 claims description 2
- 239000013543 active substance Substances 0.000 abstract description 2
- 239000007767 bonding agent Substances 0.000 abstract 4
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 18
- 229910001416 lithium ion Inorganic materials 0.000 description 18
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- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 239000007789 gas Substances 0.000 description 6
- 239000007774 positive electrode material Substances 0.000 description 6
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- 239000007773 negative electrode material Substances 0.000 description 4
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical group [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 3
- HMDDXIMCDZRSNE-UHFFFAOYSA-N [C].[Si] Chemical compound [C].[Si] HMDDXIMCDZRSNE-UHFFFAOYSA-N 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229910002804 graphite Inorganic materials 0.000 description 3
- 239000010439 graphite Substances 0.000 description 3
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- OBNDGIHQAIXEAO-UHFFFAOYSA-N [O].[Si] Chemical compound [O].[Si] OBNDGIHQAIXEAO-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical group [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 2
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- DVATZODUVBMYHN-UHFFFAOYSA-K lithium;iron(2+);manganese(2+);phosphate Chemical compound [Li+].[Mn+2].[Fe+2].[O-]P([O-])([O-])=O DVATZODUVBMYHN-UHFFFAOYSA-K 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
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- 230000001351 cycling effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000011363 dried mixture Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
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Classifications
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- 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
-
- 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
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/133—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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
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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
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- H—ELECTRICITY
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- 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
- H01M4/1391—Processes of manufacture of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
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- H—ELECTRICITY
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- 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
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- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/621—Binders
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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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/621—Binders
- H01M4/622—Binders being polymers
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- H—ELECTRICITY
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- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
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- H01M4/623—Binders being polymers fluorinated polymers
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- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
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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
- H01M4/64—Carriers or collectors
- H01M4/70—Carriers or collectors characterised by shape or form
- H01M4/80—Porous plates, e.g. sintered carriers
-
- 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
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- Chemical & Material Sciences (AREA)
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- Manufacturing & Machinery (AREA)
- Inorganic Chemistry (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The application discloses a dry electrode film with low binder content, which comprises an electrode film bonding network constructed by non-fibrous binder particles, fibrous binder, electrode active material particles and conductive agent; the fiberizing binder interweaves to form a three-dimensional bonding network, and the electrode active material particles and the conductive agent are dispersed in the three-dimensional bonding network; the non-fibrous binder particles are uniformly dispersed on the surfaces of the electrode active material particles and the conductive agent to form point-like bonding; the three-dimensional bonding network and the point bonding cooperatively construct the electrode film bonding network, the electrode film bonding network fully plays the role of the bonding agent, reduces the consumption of the bonding agent, solves the problem of uniform dispersion of the non-fibrous bonding agent on the surface of the active substance, controls the consumption of the bonding agent, improves the film forming property of the dry electrode plate, and improves the energy density, the power characteristic and the cycle life of the lithium battery.
Description
Technical Field
The application relates to a dry electrode film with low binder content, a preparation method and application thereof, and belongs to the technical field of batteries.
Background
The dry electrode technology can realize dry material mixing and coating, solvent recovery removal, solvent rectification equipment removal and most oven equipment removal because no solvent is added in the electrode manufacturing process, can greatly reduce the factory building area and the equipment cost, and obviously reduces the energy consumption and the manufacturing cost. As such, more and more lithium battery enterprises are attempting to migrate the sophisticated dry electrode core technology in supercapacitors into the lithium battery industry. However, the current dry electrode technology is still in the research and development stage in lithium ion batteries, and compared with super capacitors, the lithium battery positive electrode material has the advantages of high density, high hardness, small specific surface area, and high requirement on binders because the volume can be changed in the charge and discharge process. The dry electrode of the lithium ion battery has poor film forming property, and the problems of breakage, discontinuous production and the like exist in the production process, so that a large amount of non-conductive polymer binder is generally required to be added for promoting the dry film forming of the lithium battery material, but the addition of the excessive binder can influence the energy density and the power characteristic of the battery.
In the existing dry electrode slice preparation method, the binder is compounded with the fibrous binder by adopting a granular non-fibrous binder, so that the film forming property of the electrode slice can be improved by utilizing a synergistic effect, the non-fibrous binder is micronized by air flow crushing, the particle size is greatly reduced, but the method is difficult to realize uniform dispersion of the granular non-fibrous binder, and the dosage of the non-fibrous binder is still required to be increased for realizing the film forming of the electrode self-supporting film. In addition, the method is solvent-free dry gas phase mixing, the conductive agent with smaller density is easy to agglomerate and disperse, the dispersibility is poor, and the energy density and the power density of the lithium battery are further affected.
Disclosure of Invention
Based on the above, the application provides a dry electrode film with low binder content, a preparation method and application thereof, so as to solve the problem that the binder is difficult to disperse effectively when the binder dosage is too large or is reduced in the prior art.
The application adopts the following technical scheme:
according to a first aspect of the present application, there is provided a dry electrode film having a low binder content.
A dry electrode film with low binder content comprises an electrode film bonding network constructed by non-fibrous binder particles, fibrous binder, electrode active material particles and conductive agent;
the fiberizing binder interweaves to form a three-dimensional bonding network, and the electrode active material particles and the conductive agent are dispersed in the three-dimensional bonding network;
the non-fibrous binder particles are uniformly dispersed on the surfaces of the electrode active material particles and the conductive agent to form point-like bonding;
the three-dimensional bonding network and the point bonding cooperate to construct the electrode film bonding network;
the dry electrode film has a total content of non-fibrillated binder particles and fibrillated binder of 7wt% or less.
In one embodiment, the dry electrode film has a non-fibrillating binder particle content of 0.5 to 2wt% and a fibrillating binder content of 2 to 5wt%.
In one embodiment, the non-fibrous binder particles are at least one selected from the group consisting of sodium carboxymethyl cellulose, LA-type aqueous electrode binder, styrene-butadiene rubber, sodium alginate, polyacrylonitrile, polyurethane, polyacrylic acid, and polyvinylidene fluoride.
In one embodiment, the fiberizing binder is at least one selected from the group consisting of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, polypropylene, polyethylene, ethylene-octene copolymer, and polyimide.
In one embodiment, the kind of the conductive agent is at least one selected from conductive carbon black, carbon nanotubes, graphene, and carbon fibers.
In one embodiment, the electrode active material is a positive electrode active material or a negative electrode active material.
In one embodiment, the positive electrode active material is selected from at least one of lithium iron phosphate, lithium manganese iron phosphate, ternary, lithium cobaltate, lithium manganate, and lithium-rich manganese groups.
The negative electrode active material is at least one selected from graphite, soft carbon, hard carbon, silicon carbon and silicon oxygen.
According to a second aspect of the present application, there is provided a method for producing the above-described dry electrode film having a low binder content.
The preparation method of the dry electrode film with low binder content comprises the following steps:
dispersing a non-fibrillating binder in a solvent to form an emulsion of the non-fibrillating binder;
adding emulsion of non-fibrous binder into raw materials containing electrode active material particles and conductive agent, mixing and stirring to form a bulk mixture;
drying and jet milling the bulk mixture to obtain composite material particles;
dispersing a mixture containing composite particles and a fiberizable binder in a gas phase to obtain a fiberized mixture;
the fibrillated mixture is thermally crushed to form the low binder dry electrode film.
In one embodiment, the non-fibrillating binder is present in colloidal particles in the emulsion of the non-fibrillating binder.
The non-fibrous binder is dispersed in the form of colloidal particles in the emulsion of the non-fibrous binder by electrostatic repulsive force.
In the bulk mixture, colloidal particles are uniformly dispersed on the surfaces of the electrode active material and the conductive agent.
In one embodiment, in the composite particles, colloidal particles form the non-fibrous binder particles and are uniformly dispersed on the surfaces of the electrode active material and the conductive agent to form spot-like bonding.
In one embodiment, the colloidal particle size is 50 to 200nm.
In one embodiment, the non-fibrillating binder is present in the emulsion at a concentration of 1 to 2%.
In one embodiment, the weight ratio of the conductive agent to the raw material is 0.01-0.05:1.
In one embodiment, the solvent in the emulsion of the non-fibrillating binder is water.
In one embodiment, the mixing and stirring is performed in a double planetary stirrer at a stirring speed of 10 to 20rpm.
In one embodiment, the weight ratio of the non-fibrillating binder to the total weight of the non-fibrillating binder and raw materials is 0.005-0.02:1.
In one embodiment, the weight ratio of the fiberizing binder to the mixture is from 0.02 to 0.05:1.
In one embodiment, the fiberizable binder has a molecular weight of 10 ten thousand or more.
In one embodiment, the method of mixing and stirring to form a dough mixture comprises: dry-mixing the raw materials containing electrode active material particles and a conductive agent, then continuously adding emulsion of a non-fibrous binder into the raw materials in a dry-mixing mode, mixing and stirring, and continuously stirring after forming a granular mixture until forming a bulk mixture.
In one embodiment, the drying is freeze drying or vacuum drying.
In one embodiment, the method further comprises classifying by sieving after the jet milling step, the composite material comprising primary particles in a free state having a particle size of 100 to 300nm and secondary particles having a particle size of 5 to 10 μm.
In one embodiment, the secondary particles have a ratio of 90% or more and the primary particles in the free state have a ratio of 10% or less.
In one embodiment, the conditions for the gas phase dispersion are: the pressure is 100 Pa to 150Pa.
In one embodiment, the jet milling conditions are: the pressure is 0.75-0.85 MPa.
In one embodiment, the mixture is first shear dispersed in a high speed mixer for 20 to 40 minutes.
In one embodiment, the fiberizing binder is fibrillated under the shearing force in the gas phase dispersion after comminution.
In one embodiment, the conditions of the hot rolling are: the rolling temperature is 120-150 ℃, and the rolling pressure is 30-70 t.
According to a third aspect of the present application, there is provided a dry electrode sheet.
A dry electrode sheet comprising a self-supporting electrode film and a current collector.
A part of one end face of the self-supporting electrode film is accommodated in the gap of the current collector.
The self-supporting electrode film is selected from the dry electrode films with low binder content described above.
In one embodiment, the current collector is a porous current collector.
In one embodiment, the porous current collector is selected from at least one of a corrosion metal current collector, a perforated metal current collector, and a three-dimensional porous metal current collector.
In one embodiment, the dry electrode sheet of the lithium ion battery has a thickness of 150-400 μm.
In one embodiment, the battery direct current internal resistance of the dry electrode sheet is 2.5-3.5 mΩ.
In one embodiment, the dry electrode sheet has a tensile strength of 0.5 to 1.5MPa.
In one embodiment, the dry electrode sheet has an adhesion of 0.2 to 0.4N.
In one embodiment, the dry electrode sheet has a battery energy density of 250 to 280Wh/kg.
According to a fourth aspect of the application, the dry electrode film and the application of the dry electrode sheet in lithium batteries and sodium batteries are provided.
The application has the beneficial effects that:
1. the dry electrode film with low binder content prepared by the technical scheme of the application combines the non-fibrous binder and the fibrous binder, wherein the non-fibrous binder is fully infiltrated and mixed with the electrode active material particles in a dry mixing mode through an emulsion mode, the problem that the non-fibrous binder is agglomerated into large particles on the electrode active material particles is mainly solved, the effect of the binder can be fully exerted, the consumption of the binder is reduced, the energy density of the lithium ion battery is improved, and the internal resistance is reduced.
2. In the technical scheme of the application, the emulsion of the conductive agent, the electrode active particles and the non-fibrous binder firstly forms a bulk mixture in a dry mixing mode of raw materials, and compared with the traditional dry electrode process, the process has larger internal friction force, improves the dispersibility of the conductive agent among the electrode active particles, is easier for constructing a stable conductive path, reduces the addition amount of the conductive agent, solves the problem of large interface resistance among the electrode active particles, and improves the power characteristic of the lithium ion battery.
3. The dry electrode film preparation process with low binder content is environment-friendly and pollution-free, and is suitable for large-scale industrial production.
Drawings
Fig. 1 is a schematic diagram of a dry electrode sheet preparation process of a lithium ion battery in the application.
Fig. 2 is a schematic diagram of the internal structure of a dry electrode film with low binder content for a dry electrode sheet of a lithium ion battery according to the present application.
FIG. 3 is a schematic view showing the internal structure of the dry electrode film of comparative example 1.
Detailed Description
The following description of the embodiments of the present application will be made in detail and without limitation, the embodiments described are only some, but not all embodiments of the present application. All other embodiments, based on the embodiments of the application, which a person of ordinary skill in the art would achieve without inventive faculty, are within the scope of the application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
The method aims at solving the problem that the binder is difficult to disperse effectively when the binder is excessively used or the binder is reduced in use in the prior art. Compared with the active carbon energy storage material of the super capacitor, the electrode material (lithium iron phosphate, ternary, lithium cobaltate, lithium manganate, lithium-rich manganese-based positive electrode material, graphite, soft carbon, hard carbon, silicon carbon and the like, composite materials thereof and the like) of the battery has small specific surface area and large density, and the volume of the battery material can change in the charging and discharging process, so that the requirement on the binder is high, the film forming effect of the pole piece is poor, and the problems of pole piece breakage, discontinuous production and the like exist in the production process. In order to promote the dry film formation of lithium battery materials, a large amount of non-conductive polymer binder (more than or equal to 10%) is generally required to be added, and the inventor discovers that the addition of a large amount of non-active insulating binder seriously affects the energy density and the power characteristics of the device.
Aiming at the interface bonding problem of the active material layer and the current collector. The active material layer and the current collector are adhered together through conductive adhesive, the adhesive force between the active material layer and the current collector is poor, the interface impedance of the active material layer and the current collector is high, and particularly, the polarization problem under the working condition of high-current charge and discharge and the serious powder removal in the later charge and discharge process affect the cycling stability of the lithium ion battery.
In order to solve the problem of uniform dispersion of a non-fibrous binder on the surface of electrode active material particles, control the use amount of the binder, improve the film forming property of a dry electrode sheet, and improve the energy density, the power characteristic and the cycle life of a lithium battery, in one embodiment of the application, a dry electrode film with low binder content is provided.
Specifically, the dry electrode film with low binder content comprises an electrode film bonding network constructed by non-fibrous binder particles, fibrous binder, electrode active material particles and conductive agent;
the fiberizing binder interweaves to form a three-dimensional bonding network, and the electrode active material particles and the conductive agent are dispersed in the three-dimensional bonding network;
the non-fibrous binder particles are uniformly dispersed on the surfaces of the electrode active material particles and the conductive agent to form point-like bonding;
the three-dimensional bonding network and the point bonding cooperate to construct the electrode film bonding network;
the dry electrode film has a total content of non-fibrillated binder particles and fibrillated binder of 7wt% or less.
The application fully plays the role of the emulsion of the binder, so that the non-fibrous binder is dispersed on the surface of the active material in the form of nano particles, the dosage of the binder is reduced (less than 10%), and the energy density and the power characteristic of the device are ensured.
Further, the total content of non-fibrillated binder particles and fibrillated binder in the dry electrode film is any value of 0.5wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%, 6wt%, 7wt%, or a range of values therebetween.
Specifically, in the dry electrode film, the content of the non-fibrous binder particles is 0.5 to 2wt%, and the content of the fibrous binder is 2 to 5wt%.
Specifically, the non-fibrous binder particles are at least one selected from sodium carboxymethyl cellulose, LA-type aqueous electrode adhesives, styrene-butadiene rubber, sodium alginate, polyacrylonitrile, polyurethane, polyacrylic acid and polyvinylidene fluoride.
Specifically, the kind of the fiberizing binder is at least one kind selected from polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, polypropylene, polyethylene, ethylene-octene copolymer and polyimide.
Preferably, the fiberizing binder is polytetrafluoroethylene.
Specifically, the kind of the conductive agent is at least one selected from conductive carbon black, carbon nanotubes, graphene and carbon fibers.
Specifically, the electrode active material is a positive electrode active material or a negative electrode active material.
Specifically, the positive electrode active material is at least one selected from lithium iron phosphate, lithium manganese iron phosphate, ternary, lithium cobaltate, lithium manganate and lithium-rich manganese base.
Specifically, the negative electrode active material is at least one selected from graphite, soft carbon, hard carbon, silicon carbon and silicon oxygen.
In order to ensure that the non-fibrous binder is uniformly dispersed on the surface of the electrode active material and fully exert the cohesiveness of the binder, the non-fibrous binder is uniformly dispersed on the surface of the electrode active material in a mode of pre-dispersing the non-fibrous binder in a solvent to form a polymer emulsion and then mixing the polymer emulsion with electrode active material particles, the non-fibrous binder in the polymer emulsion exists in a colloidal particle form, the size of the non-fibrous binder is reduced to the nanometer size of a molecular state from a dry mixing micron, the non-fibrous binder is dispersed on the surface of the active material in a form of nanometer particles after liquid phase mixing, the effect of the binder can be fully exerted, and the use amount of the binder is reduced. The application provides a preparation method of the dry electrode film with low binder content.
Specifically, the preparation method of the dry electrode film with low binder content comprises the following steps:
dispersing a non-fibrillating binder in a solvent to form an emulsion of the non-fibrillating binder;
adding emulsion of non-fibrous binder into raw materials containing electrode active material particles and conductive agent, mixing and stirring to form a bulk mixture;
drying and jet milling the bulk mixture to obtain composite material particles;
dispersing a mixture containing composite particles and a fiberizable binder in a gas phase to obtain a fiberized mixture;
the fibrillated mixture is thermally crushed to form the low binder dry electrode film.
Specifically, in the emulsion of the non-fibrous binder, the non-fibrous binder exists in the form of colloidal particles.
According to the technical scheme, the non-fibrous adhesive is dispersed in the emulsion of the non-fibrous adhesive in the form of colloidal particles through electrostatic repulsive force, and the colloidal particles are uniformly dispersed on the surfaces of the electrode active material and the conductive agent in the bulk mixture.
Specifically, in the composite particles, colloidal particles form the non-fibrous binder particles and are uniformly dispersed on the surfaces of the electrode active material and the conductive agent to form spot bonding.
Specifically, the colloidal particle size is 50-200 nm.
Specifically, the concentration of the non-fibrous binder in the emulsion of the non-fibrous binder is 1-2%.
Specifically, in the raw materials, the weight ratio of the conductive agent to the raw materials is 0.01-0.05:1.
Specifically, the solvent in the emulsion of the non-fibrous binder is water.
Specifically, the mixing and stirring are performed in a double planetary stirrer, and the stirring speed is 10-20 rpm.
Specifically, the weight ratio of the non-fibrous binder to the total weight of the non-fibrous binder and the raw materials is 0.005-0.02:1.
Specifically, the weight ratio of the fiberizing binder to the mixture is 0.02-0.05:1.
Specifically, the molecular weight of the fiberizable binder is 10 ten thousand or more.
Specifically, the method for forming the bulk mixture by mixing and stirring comprises the following steps: dry-mixing the raw materials containing electrode active material particles and a conductive agent, then continuously adding emulsion of a non-fibrous binder into the raw materials in a dry-mixing mode, mixing and stirring, and continuously stirring after forming a granular mixture until forming a bulk mixture.
And (3) forming a bulk mixture, so that the surfaces of the electrode active material particles are fully soaked by the emulsion of the non-fibrous binder, and the non-fibrous binder is highly dispersed and uniformly coated on the surfaces of the electrode active material particles. In addition, compared with dry mixing, larger internal friction force exists between materials in the process and between the materials and stirring equipment, the conductive agent and electrode active material particles can be well mixed uniformly under the action of the internal friction force, an effective conductive network is easier to construct in an electrode, the non-fibrous adhesive is coated on the surface of the conductive agent material, and the stability of the conductive network structure in the post-treatment process is ensured due to the non-fibrous adhesive particles. In conclusion, the treatment mode can improve the dispersibility of the non-fibrous binder and the conductive agent, reduce the consumption of the binder, easily construct a stable conductive network in the electrode, reduce the interface resistance among electrode active material particles and improve the power characteristics of the lithium ion battery.
Specifically, the drying is freeze drying or vacuum drying.
In the drying process, under the action of the surface tension of the non-fibrous adhesive emulsion solvent, the non-fibrous adhesive is easy to agglomerate on the surface of the electrode active material particles, and in order to reduce the action of the solvent surface tension, the non-fibrous adhesive is preferably freeze-dried or vacuum-dried to inhibit the non-fibrous adhesive from agglomerating in the drying process, so that the non-fibrous adhesive is agglomerated in a micro-local way to form nano small particles and is uniformly dispersed on the surface of the electrode active material particles.
Specifically, the preparation method further comprises screening after the jet milling step, wherein the composite material comprises free primary particles with the particle size of 100-300 nm and secondary particles with the particle size of 5-10 mu m.
Specifically, the secondary particles have a ratio of 90% or more and the primary particles in a free state have a ratio of 10% or less.
The particle size of the composite material is too large, which is not beneficial to the formation of a self-supporting film of a dry electrode, and the small particle size is beneficial to the film formation of the self-supporting film of the dry electrode, but the density of an electrode plate is affected, so that the energy density is lower. Therefore, the composite material of the combination of the primary particles and the secondary particles is adopted in the preparation process of the dry electrode film, and the lithium ion battery using the dry electrode film can be ensured to have higher energy density on the basis of ensuring the dry electrode film.
Specifically, the conditions for the gas phase dispersion are: the pressure is 100 Pa to 150Pa.
Specifically, the conditions of the jet milling are as follows: the pressure is 0.75-0.85 MPa.
Specifically, the mixture is firstly sheared and dispersed in a high-speed mixer for 20-40 min.
Specifically, the pulverized fiberizable binder is fibrillated under the action of shearing force in gas-phase dispersion to form the fiberized binder, and the fiberized binder is interwoven to form a three-dimensional bonding network.
Specifically, the fiberized binder after pulverization is fiberized under the action of shearing force in gas-phase dispersion.
Specifically, the fiberizing mixture is subjected to vertical and horizontal two-step hot rolling to form a self-supporting dry electrode film.
Specifically, the conditions of the hot rolling are as follows: the rolling temperature is 120-150 ℃, and the rolling pressure is 30-70 t.
Further, the conditions of the hot rolling are as follows: the rolling temperature is 125-140 ℃, and the rolling pressure is 40-60 t.
In order to further improve the interfacial binding force between the active material layer and the current collector, further reduce the contact resistance between interfaces and improve the power performance of the battery, the application also provides a dry electrode slice.
A dry electrode sheet comprising a self-supporting electrode film and a current collector.
A part of one end face of the self-supporting electrode film is accommodated in the gap of the current collector.
The self-supporting electrode film is selected from the dry electrode films with low binder content described above.
Specifically, the current collector is a porous current collector.
Further, the porous current collector is selected from at least one of a corrosion metal current collector, a perforated metal current collector and a three-dimensional porous metal current collector.
Further, the three-dimensional porous metal current collector is selected from aluminum foam or copper foam.
Further, the porosity of the foamed aluminum is more than or equal to 98 percent, and the thickness is 100-300 mu m.
Specifically, the thickness of the dry electrode sheet is 150-400 μm.
Further, the dry electrode sheet has a thickness of 150 to 300 μm.
The three-dimensional porous current collector can improve the adhesion force of active substances and the current collector, reduce interface resistance, reduce internal resistance of the battery, improve migration rate of lithium ions, improve rate capability of the battery, improve thickness of a pole piece and improve energy density of the battery.
Specifically, the direct current internal resistance of the battery of the dry electrode slice is 2.5-3.5 mΩ.
Specifically, the tensile strength of the dry electrode slice is 0.5-1.5 MPa.
Specifically, the adhesive force of the dry electrode slice is 0.2-0.4N.
Specifically, the battery energy density of the dry electrode slice is 250-280 Wh/kg.
The application also provides the dry electrode film and application of the dry electrode plate in lithium batteries and sodium batteries.
Hereinafter, preferred embodiments and comparative embodiments are exemplified for better understanding of the present application. The following embodiments are merely illustrative of the present application, and are not limited thereto or thereby.
Unless otherwise indicated, all starting materials in the examples of the present application were purchased commercially.
In the physical property and electrochemical property test of the dry electrode slice:
the method for testing the tensile strength of the pole piece comprises the following steps: the tensile laboratory in the application is used for measuring the tensile strength of the electrode plate under the axial tensile load, an electronic tensile testing machine is adopted for testing, the electrode plate is cut into strips with the size of 2 multiplied by 4cm during testing, and the tensile speed is 30mm/min;
the method for testing the adhesive force of the pole piece comprises the following steps: cutting the dry electrode plate into to-be-detected electrode plates with the thickness not smaller than 200mm multiplied by 100mm, cutting the electrode plates by using a hundred-grid knife, adhering a self-supporting film layer by using a 3M 600 adhesive tape, and judging the adhesive force of the electrode plates by referring to a standard;
the method for testing the DC internal resistance of the battery comprises the following steps: and assembling a battery by adopting a matched dry electrode positive plate and a matched dry electrode negative plate, and testing the DC internal resistance of the battery at 50% of SOC to be the DC internal resistance of the battery by adopting an HPPC test method after the battery is formed and divided.
Example 1
As shown in the preparation flow of fig. 1, a dry electrode slice of a lithium ion battery is prepared:
s1, uniformly mixing an electrode active material (lithium iron phosphate) and a composite conductive agent (conductive carbon black: carbon nano tube: graphene=1:1:1) in a mass ratio of 97:3 in a double-planetary stirrer to obtain a mixture A (wherein the weight of the composite conductive agent is 3 g), and rotating at 10rpm. Adding non-fibrous binder sodium carboxymethyl cellulose emulsion (with the concentration of 1.5%) into the mixture A in a staged manner, wherein the mass ratio of the mixture A to the non-fibrous binder sodium carboxymethyl cellulose is 98:2, and stirring the mixture to form a bulk shape, wherein the rotating speed is 20rpm;
s2, drying the bulk mixture in vacuum at 100 ℃ for 12 hours, and carrying out jet milling and screening on the dried mixture to obtain a mixture B (the mixture B obtained after screening comprises primary particles with the particle size of 150nm and secondary particles with the particle size of 7.5 mu m);
s3, shearing and dispersing the mixture B and the fibrous binder polytetrafluoroethylene in a high-speed mixer in a mass ratio of 95:5 for 30min to obtain a mixture C (wherein the weight of the fibrous binder polytetrafluoroethylene is 5 g), carrying out jet milling on the mixture C by a high-speed jet mill to enable the binder to carry out fibrous deformation, and the jet milling air pressure is 120Pa;
s4, the mixture D is subjected to vertical and horizontal two-step hot rolling to form a self-supporting dry electrode film, the internal structure is shown in figure 2, the hot rolling temperature is 120 ℃, the rolling pressure is 35t, the electrode film and a current collector are adhered together through conductive adhesive, and the dry electrode plate of the lithium ion battery can be obtained after heating and curing, wherein the thickness of the electrode plate is 180 mu m.
Example 2
S1, uniformly mixing an electrode active material (lithium iron phosphate) and a composite conductive agent (conductive carbon black: carbon nano tube: graphene=1:1:1) in a mass ratio of 97:3 in a double-planetary stirrer to obtain a mixture A (wherein the weight of the composite conductive agent is 3 g), and rotating at 10rpm. Adding non-fibrous binder sodium carboxymethyl cellulose emulsion (with concentration of 1.5%) into the mixture A in a staged manner, wherein the mass ratio of the mixture A to the non-fibrous binder sodium carboxymethyl cellulose is 99:1, and stirring the mixture to form a bulk shape with the rotating speed of 20rpm;
S2-S3, the experimental procedure is the same as in example 1;
s4, performing vertical and horizontal two-step hot rolling on the mixture D to form a self-supporting dry electrode film, wherein the hot rolling temperature is 120 ℃, the rolling pressure is 35t, the electrode film and a current collector are adhered together through conductive adhesive, and the dry electrode plate of the lithium ion battery can be obtained after heating and curing, and the thickness of the electrode plate is 170 mu m.
Example 3
S1, uniformly mixing an electrode active material (lithium iron phosphate) and a composite conductive agent (conductive carbon black: carbon nano tube: graphene=1:1:1) in a mass ratio of 97:3 in a double-planetary stirrer to obtain a mixture A (wherein the weight of the composite conductive agent is 3 g), and rotating at 10rpm. Adding non-fibrous binder sodium carboxymethyl cellulose emulsion (with concentration of 1.5%) into the mixture A in stages, wherein the mass ratio of the mixture A to the non-fibrous binder sodium carboxymethyl cellulose is 99.5:0.5, and stirring the mixture to form a bulk shape with the rotating speed of 20rpm;
S2-S3, the experimental procedure is the same as in example 1;
s4, performing vertical and horizontal two-step hot rolling on the mixture D to form a self-supporting dry electrode film, wherein the hot rolling temperature is 120 ℃, the rolling pressure is 35t, the electrode film and a current collector are adhered together through conductive adhesive, and the dry electrode plate of the lithium ion battery can be obtained after heating and curing, and the thickness of the electrode plate is 165 mu m.
Comparative example 1
The difference from example 1 is only that in S1 mixture A is mixed with sodium carboxymethylcellulose as non-fibrillating binder, and in comparative example 1 mixture A is directly mechanically mixed with sodium carboxymethylcellulose powder, the specific steps are as follows:
s1, uniformly mixing an electrode active material (lithium iron phosphate) and a composite conductive agent (conductive carbon black: carbon nano tube: graphene=1:1:1) in a mass ratio of 97:3 in a double-planetary stirrer to obtain a mixture A (wherein the weight of the composite conductive agent is 3 g), and rotating at 10rpm. Adding non-fibrous binder sodium carboxymethyl cellulose powder into the mixture A in stages, wherein the mass ratio of the mixture A to the non-fibrous binder sodium carboxymethyl cellulose is 98:2, and stirring to form a mixture B, wherein the rotating speed of the mixture B is 20rpm;
s2, shearing and dispersing the mixture B and the fibrous binder polytetrafluoroethylene in a high-speed mixer in a mass ratio of 95:5 for 30min to obtain a mixture C (wherein the weight of the fibrous binder polytetrafluoroethylene is 5 g), carrying out jet milling on the mixture C by a high-speed jet mill to enable the binder to carry out fibrous deformation, wherein the jet milling air pressure is 120Pa;
s3, performing vertical and horizontal two-step hot rolling on the mixture D to form a self-supporting dry electrode film, wherein the hot rolling temperature is 120 ℃, the rolling pressure is 35t, the electrode film and a current collector are adhered together through conductive adhesive, and the dry electrode plate of the lithium ion battery can be obtained after heating and curing, and the thickness of the electrode plate is 180 mu m.
Test example 1
The physical properties and the electrochemical properties of the lithium ion battery dry electrode sheets prepared in examples 1 to 3 and comparative example 1 are tested, and the results are shown in table 1, and compared with the traditional dry electrode process, the dry electrode sheet prepared in the application has high tensile strength, avoids the problems of breakage and damage in the processing process of the electrode sheet, improves the winding speed of the electrode sheet and improves the production efficiency; and secondly, the electrode plate prepared by the method has higher adhesive force, reduces interface resistance, can reduce internal resistance of the battery, improves migration rate of lithium ions, improves rate capability of the battery, and improves energy density of the device.
TABLE 1 Dry electrode sheet physical Properties and electrochemical Performance test results
While the application has been described in terms of preferred embodiments, it will be understood by those skilled in the art that various changes and modifications can be made without departing from the scope of the application, and it is intended that the application is not limited to the specific embodiments disclosed.
Claims (10)
1. A dry electrode film with low binder content, which is characterized by comprising an electrode film bonding network constructed by non-fibrous binder particles, fibrous binder, electrode active material particles and conductive agent;
the fiberizing binder interweaves to form a three-dimensional bonding network, and the electrode active material particles and the conductive agent are dispersed in the three-dimensional bonding network;
the non-fibrous binder particles are uniformly dispersed on the surfaces of the electrode active material particles and the conductive agent to form point-like bonding;
the three-dimensional bonding network and the point bonding cooperate to construct the electrode film bonding network;
the dry electrode film has a total content of non-fibrillated binder particles and fibrillated binder of 7wt% or less.
2. The low binder dry electrode film according to claim 1, wherein the dry electrode film has a non-fibrillated binder particle content of 0.5 to 2wt% and a fibrillated binder content of 2 to 5wt%.
3. The low binder content dry electrode film according to claim 1, wherein the non-fibrous binder particles are at least one selected from the group consisting of sodium carboxymethyl cellulose, LA-type aqueous electrode binder, styrene-butadiene rubber, sodium alginate, polyacrylonitrile, polyurethane, polyacrylic acid, polyvinylidene fluoride;
preferably, the type of the fiberizing binder is at least one selected from polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, polypropylene, polyethylene, ethylene-octene copolymer, polyimide.
4. The low binder content dry electrode film according to claim 1, wherein the kind of the conductive agent is at least one selected from the group consisting of conductive carbon black, carbon nanotubes, graphene, and carbon fibers.
5. The method for producing a low binder content dry electrode film according to any one of claims 1 to 4, comprising:
dispersing a non-fibrillating binder in a solvent to form an emulsion of the non-fibrillating binder;
adding emulsion of non-fibrous binder into raw materials containing electrode active material particles and conductive agent, mixing and stirring to form a bulk mixture;
drying and jet milling the bulk mixture to obtain composite material particles;
dispersing a mixture containing composite particles and a fiberizable binder in a gas phase to obtain a fiberized mixture;
the fibrillated mixture is thermally crushed to form the low binder dry electrode film.
6. The method of claim 5, wherein the non-fibrillating binder is present in colloidal particles in the emulsion of the non-fibrillating binder;
the size of the colloidal particles is 50-200 nm;
preferably, the concentration of the non-fibrous binder in the emulsion of the non-fibrous binder is 1-2%;
preferably, in the raw materials, the weight ratio of the conductive agent to the raw materials is 0.01-0.05:1;
preferably, the weight ratio of the non-fibrous binder to the total weight of the non-fibrous binder and the raw materials is 0.005-0.02:1;
preferably, the weight ratio of the fiberizable binder to the mixture is from 0.02 to 0.05:1;
preferably, the molecular weight of the fiberizable binder is 10 ten thousand or more.
7. The method of claim 5, wherein the method of mixing and stirring to form a dough comprises: firstly, dry-mixing raw materials containing electrode active material particles and a conductive agent, then continuously adding emulsion of a non-fibrous binder into the raw materials in a dry-mixing mode, mixing and stirring, and continuously stirring after forming a granular mixture until forming a bulk mixture;
preferably, the preparation method further comprises screening after the jet milling step, wherein the composite material comprises free primary particles with the particle size of 100-300 nm and secondary particles with the particle size of 5-10 mu m;
preferably, the conditions of the gas phase dispersion are: the pressure is 100 Pa to 150Pa.
8. A dry electrode sheet, characterized in that the dry electrode sheet comprises a self-supporting electrode film and a current collector;
a part of one end face of the self-supporting electrode film is accommodated in the gap of the current collector;
the self-supporting electrode film is selected from at least one of the dry electrode films with low binder content according to any one of claims 1 to 4.
9. The dry electrode tab of claim 8, wherein the current collector is a porous current collector;
preferably, the porous current collector is selected from at least one of a corrosion metal current collector, a perforated metal current collector, a three-dimensional porous metal current collector;
preferably, the direct current internal resistance of the battery of the dry electrode slice is 2.5-3.5 mΩ;
preferably, the tensile strength of the dry electrode slice is 0.5-1.5 MPa;
preferably, the adhesive force of the dry electrode slice is 0.2-0.4N;
preferably, the battery energy density of the dry electrode sheet is 250-280 Wh/kg.
10. The use of the dry electrode sheet of claim 8 or 9 in lithium batteries and sodium batteries.
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CN118588942A (en) * | 2024-08-07 | 2024-09-03 | 远景动力技术(鄂尔多斯市)有限公司 | All-solid dry method positive electrode plate and all-solid battery |
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CN118412433A (en) * | 2024-06-28 | 2024-07-30 | 中国第一汽车股份有限公司 | Dry electrode film, preparation method thereof, dry electrode and solid-state battery |
CN118588942A (en) * | 2024-08-07 | 2024-09-03 | 远景动力技术(鄂尔多斯市)有限公司 | All-solid dry method positive electrode plate and all-solid battery |
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