CN115295764A - Negative pole piece, preparation method thereof and secondary battery - Google Patents

Negative pole piece, preparation method thereof and secondary battery Download PDF

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Publication number
CN115295764A
CN115295764A CN202210907036.2A CN202210907036A CN115295764A CN 115295764 A CN115295764 A CN 115295764A CN 202210907036 A CN202210907036 A CN 202210907036A CN 115295764 A CN115295764 A CN 115295764A
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layer
buffer layer
expansion
negative electrode
protective layer
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钟应声
张传健
唐文
黄海旭
张�浩
江柯成
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Jiangsu Zenio New Energy Battery Technologies Co Ltd
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Jiangsu Zenio New Energy Battery Technologies Co Ltd
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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
    • H01M4/134—Electrodes based on metals, Si or alloys
    • 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
    • H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
    • 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
    • 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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  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention belongs to the technical field of secondary batteries, and particularly relates to a negative pole piece and a secondary battery. The negative pole piece comprises a negative current collector and a diaphragm layer arranged on at least one surface of the negative current collector, wherein the diaphragm layer comprises the following raw materials in parts by weight: 80 to 98 parts of silicon material, 0.1 to 5 parts of gas generating material, 1 to 10 parts of binder and 0.2 to 8 parts of conductive agent. The negative pole piece can effectively control the expansion of the electrode material in the circulation process, control the capacity attenuation and improve the circulation stability.

Description

Negative pole piece, preparation method thereof and secondary battery
Technical Field
The invention belongs to the technical field of secondary batteries, and particularly relates to a negative pole piece, a preparation method of the negative pole piece and a secondary battery.
Background
Currently, lithium Ion Batteries (LIBs) are widely used in portable devices and electronic products, however, there are still some problems in the application of electric vehicles and renewable energy storage power grids, including energy density, material cost, and safety in use. Therefore, it is very important that the performance of developing a lithium ion battery having high energy density and long cycle life is excellent.
Silicon (Si) has excellent theoretical specific surface area capacity and was developed as one of attractive candidate anode materials, with silicon anodes having very high theoretical capacity (about 4200 mAh/g), about 10 times the current commercial graphite anode capacity (about 370 mAh/g). Unfortunately, silicon has a serious inherent problem/delithiation process during lithiation. Repeated insertion and extraction of lithium ions easily causes a large volume change (about 300%) and rupture, resulting in poor electronic conductivity and uncontrolled secondary growth of a Solid Electrolyte Interface (SEI) film, which eventually destroys the integrity of the battery, resulting in rapid capacity fade.
Carbon-coated silicon is an effective strategy for inhibiting volume expansion of a silicon negative electrode material in a lithium ion battery and improving cycle stability. However, optimization of the carbon/silicon coating material structure and improvement of structural stability and flexibility on the negative electrode sheet layer are still a great challenge.
Disclosure of Invention
One of the objects of the present invention is: aiming at the defects of the prior art, the negative pole piece is provided, the expansion of the electrode material in the circulating process can be effectively controlled, the capacity attenuation is controlled, and the circulating stability is improved.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides a negative pole piece, includes the negative pole mass flow body and sets up in the diaphragm layer of the at least one surface of negative pole mass flow body, the diaphragm layer includes the raw materials of following parts by weight: 80-98 parts of silicon material, 0.1-5 parts of gas generating material, 1-10 parts of binder and 0.2-8 parts of conductive agent.
Preferably, the membrane layer comprises an expansion layer arranged on the surface of the negative current collector, a buffer layer arranged on one side, far away from the negative current collector, of the expansion layer, and a protection layer arranged on the buffer layer, far away from the expansion layer.
Preferably, the thickness of the membrane layer is 0.035-0.95 mm, and the compaction density of the membrane layer is 1.05-1.90 g/cm 3 。
Preferably, the pore diameters of the expansion layer, the buffer layer and the protective layer satisfy the following relation: k Intumescent layer 50 ≥K Buffer layer 50 ≥K Protective layer 50 ，K Intumescent layer 50 ≤0.035mm，K Protective layer 50 ＞0。
Preferably, the mass ratio of the silicon material in the expansion layer, the buffer layer and the protective layer is 80-98%, the mass ratio of the gas generating material in the expansion layer, the buffer layer and the protective layer is 0.1-5%, the mass ratio of the binder in the expansion layer, the buffer layer and the protective layer is 1-10%, and the mass ratio of the conductive agent in the expansion layer, the buffer layer and the protective layer is 0.2-8%.
Preferably, the content of the silicon material in the expansion layer is greater than that of the buffer layer, and the content of the silicon material in the buffer layer is greater than that of the protective layer.
Preferably, the content of the gas production material in the expansion layer is larger than that of the gas production material in the buffer layer and/or the content of the gas production material in the expansion layer is larger than that of the gas production material in the protective layer.
Preferably, the content of the binder in the expansion layer is greater than the content of the binder in the buffer layer and/or the content of the binder in the protective layer is greater than the content of the binder in the buffer layer.
Preferably, the content of the conductive agent in the expansion layer is larger than that in the buffer layer and/or the content of the conductive agent in the expansion layer is larger than that in the protective layer.
The second purpose of the invention is: aiming at the defects of the prior art, the preparation method of the negative pole piece is provided, the slurry with different silicon material contents and gas production material contents is respectively prepared, and the expansion layer, the buffer layer and the protective layer are respectively obtained by coating.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a negative pole piece comprises the following steps:
step S1, mixing a silicon material, a gas generating material, a binder and a conductive agent according to a first proportion, adding a solvent, and stirring to obtain a first negative electrode slurry;
s2, coating the first negative electrode slurry on at least one surface of a negative electrode current collector, and drying to form an expansion layer; s3, mixing the silicon material, the gas generating material, the binder and the conductive agent according to a second proportion, adding the solvent and stirring to prepare a second cathode slurry;
s4, coating the second cathode slurry on the surface of the expansion layer, and drying to form a buffer layer;
s5, mixing the silicon material, the gas generating material, the binder and the conductive agent according to a third proportion, adding the solvent and stirring to prepare third negative electrode slurry;
and S6, coating the third negative electrode slurry on the surface of the buffer layer, and drying to form a protective layer to obtain the negative electrode piece.
The third purpose of the invention is: aiming at the defects of the prior art, the secondary battery is provided, and has the advantages of high capacity, long cycle life, slow capacity attenuation and good cycle stability.
In order to achieve the purpose, the invention adopts the following technical scheme:
a secondary battery comprises the negative pole piece.
Compared with the prior art, the invention has the beneficial effects that: according to the invention, the silicon material is arranged in the pole piece to increase the capacity and the gas production material is added, so that the pole piece has a certain porosity, space is provided for the volume expansion of the silicon material, the expansion of the electrode material in the circulation process is effectively slowed down, the capacity attenuation is controlled, and the circulation stability is improved.
Drawings
Fig. 1 is a schematic structural diagram of a negative electrode sheet of the present invention.
Wherein: 1. a negative current collector; 2. a membrane layer; 21. an intumescent layer; 22. a buffer layer; 23. a protective layer; 24. a pore; 25. a silicon material.
Detailed Description
The present invention will be described in further detail with reference to the following detailed description and the accompanying drawings, but the embodiments of the invention are not limited thereto.
1. A negative pole piece can effectively control the expansion of an electrode material in the circulating process, control the capacity attenuation and improve the circulating stability.
The utility model provides a negative pole piece, includes negative pole mass flow body 1 and sets up in the diaphragm layer 2 of 1 at least one surface of negative pole mass flow body, diaphragm layer 2 includes the raw materials of following parts by weight: 80 to 98 portions of silicon material 25, 0.1 to 5 portions of gas generating material, 1 to 10 portions of adhesive and 0.2 to 8 portions of conductive agent.
According to the invention, the silicon material 25 is arranged in the pole piece to increase the capacity and the gas generating material, so that the pole piece has a certain porosity 24, space is provided for the volume expansion of the silicon material 25, the expansion of the electrode material in the circulation process is effectively slowed down, the capacity attenuation is controlled, and the circulation stability is improved.
The silicon material 25 contains at least one of carbon-coated nano or micro silicon material 25, nano or micro silicon oxide and carbon composite material, silicon-carbon nano or micro wire material, siOx (2 > x > 0) carbon nano or micro composite material; further, the silicon material 25 contains at least one of artificial graphite, natural ink, modified graphite, soft carbon, and hard carbon; further, the silicon material 25 contains at least one element selected from oxygen, lithium, magnesium, sodium, potassium, calcium, beryllium, strontium, zirconium, vanadium, boron, zinc, aluminum, silver, and fluorine. The silicon material 25 may be a single particle or a composite particle; further, the composite particle is obtained by polymerizing a plurality of single particles.
The gas generating material is at least one of ammonium fluoride, ammonium chloride and ammonium nitrate.
The binder is at least one of monomer, polymer and copolymer of acrylonitrile, vinylidene fluoride, sodium carboxymethylcellulose, methacryl, acrylic acid, dopamine, acrylamide, amide, imide, acrylate, styrene butadiene rubber, vinyl alcohol, sodium alginate, chitosan, glycol and the like.
The conductive agent is at least one of conductive carbon black, acetylene black, graphite, graphene, a micro-nano fibrous conductive agent and a micro-nano tubular conductive agent.
The negative current collector 1 is at least one of copper foil, porous copper foil, foamed nickel/copper foil, galvanized copper foil, nickel-plated copper foil, carbon-coated copper foil, nickel foil, titanium foil, carbon-containing porous copper foil and single-metal or multi-metal porous copper foil. Copper foil, copper foil such as zinc-plated copper foil and nickel-plated copper foil and carbon-coated copper foil are preferable.
In some embodiments, the membrane layer 2 includes an expansion layer 21 disposed on the surface of the negative electrode current collector 1, a buffer layer 22 disposed on a side of the expansion layer 21 away from the negative electrode current collector 1, and a protection layer 23 disposed on the buffer layer 22 away from the expansion layer 21.
Different expansion layers 21, buffer layers 22 and protective layers 23 are arranged in the membrane layer 2, so that the respective layers respectively play respective roles, and the three layers cooperate to obtain a pole piece with high capacity and small expansion, and particularly good electrochemical performance and cycling stability.
In some embodiments, the membrane layer 2 has a thickness of 0.035 to 0.95mm and the membrane layer 2 has a compacted density of 1.05 to 1.90g/cm 3 . The membrane layer 2 varies with the thickness of the expansion layer 21, the cushioning layer 22 and the protective layer 23, and preferably the membrane layer 2 has a compacted density of 1.45 to 1.72g/cm 3 。
In some embodiments, the diameters of the pores 24 of the expansion layer 21, the buffer layer 22, and the protective layer 23 satisfy the following relationship: k Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ，K Expanding layer 2150 ≤0.035mm，K Protective layer 2350＞0。
The expansion layer 21, the buffer layer 22 and the protection layer 23 are all provided with pores 24, the volume ratio of the pores 24 in the expansion layer 21, the buffer layer 22 and the protection layer 23 is reduced in sequence, the pores 24 are more and more dense in sequence, and conversely, the diameters of the pores 24 in the protection layer 23, the buffer layer 22 and the expansion layer 21 are more and more straight. K above Intumescent layer 2150 The cumulative distribution percentage of all the pores 24 in the expansion layer 21 is reachedPore 24 diameter value, K, corresponding to 50% Buffer layer 2250 The diameter value, K, of the pores 24 corresponding to a cumulative distribution percentage of 50% of all the pores 24 in the buffer layer 22 Protective layer 2350 The length unit of the diameter of the pores 24 is one of nm, μm, mm, cm, dm, and m according to the description suitability, for the value of the diameter of the pores 24 corresponding to the cumulative distribution percentage of all the pores 24 in the protective layer 23 reaching 50%.
In some embodiments, the mass ratio of the silicon material 25 in the expansion layer 21, the buffer layer 22 and the protection layer 23 is 80% to 98%, the mass ratio of the gas generating material in the expansion layer 21, the buffer layer 22 and the protection layer 23 is 0.1% to 5%, the mass ratio of the binder in the expansion layer 21, the buffer layer 22 and the protection layer 23 is 1% to 10%, and the mass ratio of the conductive agent in the expansion layer 21, the buffer layer 22 and the protection layer 23 is 0.2% to 8%.
In some embodiments, the amount of silicon material 25 in the expansion layer 21 is greater than the amount of silicon material 25 in the buffer layer 22, and the amount of silicon material 25 in the buffer layer 22 is greater than the amount of silicon material 25 in the protective layer 23.
Further, the ratio of the mass of silicon in 35% or more of the expansion layer 21 to the mass of the expansion layer 21 is greater than or equal to the ratio of the mass of silicon in the buffer layer 22 to the mass of the buffer layer 22 is greater than or equal to the ratio of the mass of silicon in the protective layer 23 to the mass of the protective layer 23 by >0.5%, or the ratio of the mass of silicon material 25 in 85% or more of the expansion layer 21 to the mass of the expansion layer 21 is greater than or equal to the ratio of the mass of silicon material 25 in the buffer layer 22 to the mass of the buffer layer 22 is greater than or equal to the ratio of the mass of silicon material 25 in the protective layer 23 to the mass of the protective layer 23 by >1.0%.
In some embodiments, the amount of gas-generating material in the expansion layer 21 is greater than the amount of gas-generating material in the buffer layer 22 and/or the amount of gas-generating material in the expansion layer 21 is greater than the amount of gas-generating material in the protective layer 23.
In some embodiments, the binder content of the expansion layer 21 is greater than the binder content of the buffer layer 22 and/or the binder content of the protective layer 23 is greater than the binder content of the buffer layer 22.
In some embodiments, the amount of conductive agent in the intumescent layer 21 is greater than the amount of conductive agent in the buffer layer 22 and/or the amount of conductive agent in the intumescent layer 21 is greater than the amount of conductive agent in the protective layer 23.
2. A preparation method of a negative pole piece comprises the following steps:
step S1, mixing a silicon material 25, a gas generating material, a binder and a conductive agent according to a first proportion, adding a solvent, and stirring to obtain a first negative electrode slurry;
s2, coating the first negative electrode slurry on at least one surface of a negative electrode current collector 1, and drying to form an expansion layer 21;
s3, mixing the silicon material 25, the gas generating material, the binder and the conductive agent according to a second proportion, adding a solvent, and stirring to obtain a second cathode slurry;
s4, coating the second cathode slurry on the surface of the expansion layer 21, and drying to form a buffer layer 22;
s5, mixing the silicon material 25, the gas generating material, the binder and the conductive agent according to a third proportion, adding a solvent, and stirring to obtain third negative electrode slurry;
and S6, coating the third negative electrode slurry on the surface of the buffer layer 22, and drying to form a protective layer 23 to obtain the negative electrode plate.
A preparation method of a negative pole piece is characterized in that slurries with different silicon material 25 contents and gas production material contents are respectively prepared, and an expansion layer 21, a buffer layer 22 and a protection layer 23 are respectively obtained through coating. In the preparation method of the negative pole piece, the drying temperature is 50-120 ℃, and the drying time is 4-20 h. The pressing and rolling pressure of the tablet is 0.05-0.55 MPa. Further, the rolling pressure required by the first tabletting is less than that required by the subsequent tabletting for two times. Wherein the first proportion is as follows by mass percent: 2594 to 96 percent of silicon material, 1.5 to 3 percent of binder, 1.5 to 1.8 percent of conductive agent and 0.7 to 1.5 percent of gas generating material; the second proportion is that the following raw materials by mass percent: 2596-97% of silicon material, 1.2-1.5% of adhesive, 1.1-1.5% of conductive agent and 0.4-0.6% of gas generating material; the third proportion is that the following raw materials by mass percent: 2596-98% of silicon material, 1.5-3% of binder, 0.6-0.8% of conductive agent and 0.2-0.3% of gas production material. The solvent is one of deionized water, purified water and ultrapure water.
3. A secondary battery has a high capacity and a long cycle life, and is low in capacity fading and good in cycle stability.
A secondary battery comprises the negative pole piece.
Specifically, a secondary battery, including positive plate, barrier film, negative pole piece, electrolyte and casing, the barrier film is used for separating positive plate and negative pole piece, the casing is used for encapsulating positive plate, barrier film, negative pole piece and electrolyte, the negative pole piece is foretell negative pole piece.
Positive electrode
The positive plate comprises a positive current collector and a positive active material layer arranged on at least one surface of the positive current collector, wherein the positive active material layer comprises a positive active material, and the positive active material can be a compound including but not limited to a chemical formula such as Li a Ni x Co y M z O 2-b N b (wherein 0.95. Ltoreq. A. Ltoreq.1.2. X>0,y ≥ 0,z ≥ 0, and x + y + z =1,0 ≤ b ≤ 1,M is selected from one or more combinations of Mn and Al, and N is selected from one or more combinations of F, P, S), and the positive electrode active material can also be selected from the group consisting of, but not limited to, liCoO 2 、LiNiO 2 、LiVO 2 、LiCrO 2 、LiMn 2 O 4 、LiCoMnO 4 、Li 2 NiMn 3 O 8 、LiNi 0.5 Mn 1.5 O 4 、LiCoPO 4 、LiMnPO 4 、LiFePO 4 、LiNiPO 4 、LiCoFSO 4 、CuS 2 、FeS 2 、MoS 2 、NiS、TiS 2 And the like. The positive electrode active material may be further modified, and the method for modifying the positive electrode active material is known to those skilled in the art, for example, the positive electrode active material may be modified by coating, doping, etc., and the materials used in the modification treatment may include, but are not limited to, al, B, POne or more of Zr, si, ti, ge, sn, mg, ce, W, etc. And the positive electrode current collector is generally a structure or a part for collecting current, and the positive electrode current collector may be any material suitable for being used as a positive electrode current collector of a lithium ion battery in the field, for example, the positive electrode current collector may include, but is not limited to, a metal foil and the like, and more specifically, may include, but is not limited to, an aluminum foil and the like.
Electrolyte solution
The lithium ion battery also comprises electrolyte, and the electrolyte comprises an organic solvent, electrolyte lithium salt and an additive. Wherein the electrolyte lithium salt may be LiPF used in a high-temperature electrolyte 6 And/or LiBOB; or LiBF used in low-temperature electrolyte 4 、LiBOB、LiPF 6 At least one of; also can be LiBF adopted in anti-overcharging electrolyte 4 、LiBOB、LiPF 6 At least one of, liTFSI; may also be LiClO 4 、LiAsF 6 、LiCF 3 SO 3 、LiN(CF 3 SO 2 ) 2 At least one of (1). And the organic solvent may be a cyclic carbonate including PC, EC; or chain carbonates including DFC, DMC, or EMC; and also carboxylic acid esters including MF, MA, EA, MP, etc. And additives include, but are not limited to, film forming additives, conductive additives, flame retardant additives, overcharge prevention additives, controlling H in electrolytes 2 At least one of additives of O and HF content, additives for improving low temperature performance, and multifunctional additives.
Preferably, the material of casing is one of stainless steel, plastic-aluminum membrane. More preferably, the housing is an aluminum plastic film.
Example 1
1, preparing a negative pole piece:
1.1A silicon-containing layered negative plate comprises a negative current collector 1, copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing the silicon material 25, the conductive agent, the binder and the gas production material, adding deionized water, stirring and pulping to obtain negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protection layer 23 (membrane), namely the silicon-containing layered negative electrode plate.
The drying temperature is 105 ℃, and the drying time is 6h.
The rolling pressure required by the first tabletting is 0.09MPa, and the rolling pressure required by the subsequent tabletting for two times is 1.65MPa and 1.89MPa respectively.
1.3 the thickness of one layer of membrane is 0.132mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane, as shown in fig. 1;
the pore 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and pore 24 volume accounts for and reduces in proper order, and pore 24 is in proper order denser, and protective layer 23, buffer layer 22, inflation layer 21 pore 24 diameter are in proper order more rare more big more, satisfy: k is more than or equal to 0.014m Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 accounts for 95.7%, 97% and 97.6% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23, respectively, and the silica content of each of the expansion layer 21, the buffer layer 22 and the protection layer 23 accounts for 16.2%, 12.8% and 3.1% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23, respectively.
The binder is prepared from polyacrylonitrile and styrene-butadiene latex in a mass ratio of 1:1, the binder respectively accounts for 1.5 percent, 1.2 percent and 1.5 percent of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating substance is ammonium fluoride which respectively accounts for 1.5 percent, 0.5 percent and 0.2 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from conductive carbon black and conductive carbon nanotubes in a mass ratio of 8:2, and the conductive agent accounts for 1.8 percent, 1.2 percent and 0.6 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
2, preparing the lithium ion battery:
the silicon-containing layered negative plate, the isolating membrane and the positive plate (containing 96.5 percent of LiNi-Co-Mn oxide) prepared in the above way 0.8 Co 0.1 Mn 0.1 O 2 Positive electrode active material) to obtain a battery core, sealing the battery core, bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 2
1, preparing a negative pole piece:
1.1A silicon-containing layered negative plate comprises a negative current collector 1, copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing the silicon material 25, the conductive agent, the binder and the gas production material, adding deionized water, stirring and pulping to obtain negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 105 ℃, and the drying time is 6h.
The rolling pressure required by the first tabletting is 0.09MPa, and the rolling pressure required by the subsequent tabletting for two times is 1.65MPa and 1.89MPa respectively.
1.3 the thickness of one layer of membrane is 0.136mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
the hole 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and the hole 24 volume accounts for and reduces in proper order, and hole 24 is in proper order denser, and protective layer 23, buffer layer 22, the 21 hole 24 diameters of inflation layer more rare in proper order more big, satisfy: k is more than or equal to 0.014m Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 is 95.8%, 97.2% and 97% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23, wherein the mass of the silica in each of the expansion layer 21, the buffer layer 22 and the protection layer 23 is 15.8%, 12.7% and 2.9% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23 respectively.
The binder is prepared from polyacrylonitrile and styrene-butadiene latex in a mass ratio of 1:1, the binder respectively accounts for 2.0 percent, 1.2 percent and 2.0 percent of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 0.7 percent, 0.4 percent and 0.2 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from conductive carbon black and conductive carbon nanotubes according to the mass ratio of 8:2, and the conductive agent accounts for 1.5 percent, 1.2 percent and 0.8 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
2, preparing the lithium ion battery:
silicon-containing layered negative plate, isolating film and positive plate (containing 96.5% of Li, ni, co and Mn)Oxide LiNi 0.8 Co 0.1 Mn 0.1 O 2 Positive electrode active material) to obtain a battery core, sealing and bundling the battery core, installing the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: compacting the density, preparing the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the diaphragm after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 3
1, silicon-containing layered negative plate:
1.1A silicon-containing layered negative plate comprises a negative current collector 1, copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing the silicon material 25, the conductive agent, the binder and the gas production material, adding deionized water, stirring and pulping to obtain negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 105 ℃, and the drying time is 6h.
The rolling pressure required by the first tabletting is 0.09MPa, and the rolling pressure required by the subsequent tabletting for two times is 1.65MPa and 1.89MPa respectively.
1.3 the thickness of one layer of membrane is 0.137mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
expansion layer 21, buffer layer22. The pore 24 diameter in the protective layer 23 reduces in proper order, and pore 24 volume accounts for and reduces in proper order, and pore 24 is in proper order denser, and protective layer 23, buffer layer 22, the 21 pore 24 diameters of inflation layer are in proper order more rare more big more, satisfy: k is more than or equal to 0.014m Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 is 95.2%, 96.8% and 96.5% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23, wherein the mass of the silica in each of the expansion layer 21, the buffer layer 22 and the protection layer 23 is 15.5%, 12.7% and 2.8% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23.
The binder is prepared from polyacrylonitrile and styrene-butadiene latex in a mass ratio of 1:1, the binder respectively accounts for 2.5%, 1.5% and 2.5% of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 0.8 percent, 0.5 percent and 0.2 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from conductive carbon black and conductive carbon nanotubes in a mass ratio of 8:2, and the conductive agent accounts for 1.8 percent, 1.2 percent and 0.6 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
2, preparing the lithium ion battery:
a silicon-containing layered negative plate, a separation film and a positive plate (containing 96.5 percent of LiNi-Co-Mn oxide LiNi) 0.8 Co 0.1 Mn 0.1 O 2 Positive electrode active material) to obtain a battery core, sealing and bundling the battery core, installing the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 4
1, silicon-containing layered negative plate:
1.1A silicon-containing layered negative plate comprises a negative current collector 1 copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing the silicon material 25, the conductive agent, the binder and the gas production material, adding deionized water, stirring and pulping to obtain negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 105 ℃, and the drying time is 6h.
The rolling pressure required by the first tabletting is 0.09MPa, and the rolling pressure required by the subsequent tabletting for two times is 1.65MPa and 1.89MPa respectively.
1.3, the thickness of one layer of the membrane is 0.143mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
the pore 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and pore 24 volume accounts for and reduces in proper order, and pore 24 is in proper order denser, and protective layer 23, buffer layer 22, inflation layer 21 pore 24 diameter are in proper order more rare more big more, satisfy: k is more than or equal to 0.014m Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 is 94.7%, 96.8% and 96% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23, wherein the mass of the silica in each of the expansion layer 21, the buffer layer 22 and the protective layer 23 is 14.7%, 12.1% and 2.5% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23.
The binder is prepared from polyacrylonitrile and styrene-butadiene latex in a mass ratio of 1:1, the binder respectively accounts for 3.0 percent, 1.5 percent and 3.0 percent of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 0.8 percent, 0.5 percent and 0.2 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from conductive carbon black and conductive carbon nanotubes in a mass ratio of 8:2, and the conductive agent accounts for 1.5 percent, 1.2 percent and 0.8 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
2, preparing the lithium ion battery:
a silicon-containing layered negative plate, a separation film and a positive plate (containing 96.5 percent of LiNi-Co-Mn oxide LiNi) 0.8 Co 0.1 Mn 0.1 O 2 Positive electrode active material) to obtain a battery core, sealing the battery core, bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 5
1, silicon-containing layered negative plate:
1.1A silicon-containing layered negative plate comprises a negative current collector 1 copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing a silicon material 25, a conductive agent, a binder and a gas generating material, adding deionized water, stirring, pulping to obtain a negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 85 ℃, and the drying time is 12h.
The rolling pressure required by the first tabletting is 0.13MPa, and the rolling pressure required by the subsequent tabletting for two times is 1.85MPa and 1.95MPa respectively.
1.3, the thickness of one layer of the membrane is 0.119mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
the pore 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and pore 24 volume accounts for and reduces in proper order, and pore 24 is in proper order denser, and protective layer 23, buffer layer 22, inflation layer 21 pore 24 diameter are in proper order more rare more big more, satisfy: 0.018m is more than or equal to K Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the carbon-coated micron silicon material 25 is mixed with a graphite composite material to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 is 95.7%, 97% or 97.6% of the mass of the expansion layer 21, the buffer layer 22 or the protective layer 23, wherein the mass of the silica in each of the expansion layer 21, the buffer layer 22 or the protective layer 23 is 15.6%, 12.4% or 3.0% of the mass of the expansion layer 21, the buffer layer 22 or the protective layer 23.
The adhesive is prepared from polyacrylonitrile and polyvinylidene fluoride according to a mass ratio of 1:1, the binder respectively accounts for 1.5 percent, 1.2 percent and 1.5 percent of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 1 percent, 0.6 percent and 0.3 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from acetylene black and a conductive carbon nano tube according to the mass ratio of 8:2, and the conductive agent accounts for 1.8 percent, 1.2 percent and 0.6 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
Preparing a lithium ion battery:
a silicon-containing layered negative plate, an isolating film and a positive plate (containing 96.5 percent of lithium iron phosphate LiFePO) 4 Positive electrode active material) to obtain a battery core, sealing and bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 6
1, silicon-containing layered negative plate:
1.1A silicon-containing layered negative plate comprises a negative current collector 1, copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing the silicon material 25, the conductive agent, the binder and the gas production material, adding deionized water, stirring and pulping to obtain negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 85 ℃, and the drying time is 12h.
The rolling pressure required by the first tabletting is 0.13MPa, and the rolling pressures required by the subsequent tabletting for two times are 1.85MPa and 1.95MPa respectively.
1.3, the thickness of one layer of membrane is 0.117mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
the pore 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and pore 24 volume accounts for and reduces in proper order, and pore 24 is in proper order denser, and protective layer 23, buffer layer 22, inflation layer 21 pore 24 diameter are in proper order more rare more big more, satisfy: 0.018m is more than or equal to K Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 is 95.2%, 97% and 97.1% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23, wherein the silica content of each of the expansion layer 21, the buffer layer 22 and the protection layer 23 accounts for 15.5%, 12.5% and 2.8% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23 respectively.
The adhesive is prepared from polyacrylonitrile and polyvinylidene fluoride according to a mass ratio of 1:1, the binder respectively accounts for 2%, 1.2% and 2% of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 1%, 0.6% and 0.3% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from acetylene black and conductive carbon nanotubes in a mass ratio of 8:2, and the conductive agent accounts for 1.8%, 1.2% and 0.6% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23, respectively.
2, preparing the lithium ion battery:
a silicon-containing layered negative plate, an isolating film and a positive plate (containing 96.5 percent of lithium iron phosphate LiFePO) 4 Positive electrode active material) to obtain a battery core, sealing the battery core, binding the battery core, installing a battery shell in the battery core, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, and standingAnd carrying out formation and capacity grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 7
1, silicon-containing layered negative plate:
1.1A silicon-containing layered negative plate comprises a negative current collector 1 copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing the silicon material 25, the conductive agent, the binder and the gas production material, adding deionized water, stirring and pulping to obtain negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 85 ℃, and the drying time is 12h.
The rolling pressure required by the first tabletting is 0.13MPa, and the rolling pressure required by the subsequent tabletting for two times is 1.85MPa and 1.95MPa respectively.
1.3, the thickness of one layer of the membrane is 0.127mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
the pore 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and pore 24 volume accounts for and reduces in proper order, and pore 24 is in proper order denser, and protective layer 23, buffer layer 22, inflation layer 21 pore 24 diameter are in proper order more rare more big more, satisfy: 0.018m is more than or equal to K Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 is 94.7%, 96.7% and 96.6% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23, wherein the mass of the silica in each of the expansion layer 21, the buffer layer 22 and the protection layer 23 is 15.3%, 12.2% and 2.5% of the mass of the expansion layer 21, the buffer layer 22 and the protection layer 23.
The adhesive is prepared from polyacrylonitrile and polyvinylidene fluoride according to a mass ratio of 1:1, the binder respectively accounts for 2.5 percent, 1.5 percent and 2.5 percent of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 1 percent, 0.6 percent and 0.3 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from acetylene black and conductive carbon nanotubes in a mass ratio of 8:2, and the conductive agent accounts for 1.8%, 1.2% and 0.6% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23, respectively.
2, preparing the lithium ion battery:
a silicon-containing layered negative plate, an isolating film and a positive plate (containing 96.5 percent of lithium iron phosphate LiFePO) 4 Positive electrode active material) to obtain a battery core, sealing and bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Example 8:
1, silicon-containing layered negative plate:
1.1A silicon-containing layered negative plate comprises a negative current collector 1 copper foil and two layers of diaphragms on the copper foil, wherein the diaphragms comprise a silicon material 25, a binder and a conductive agent.
1.2A preparation method of a silicon-containing layered negative plate comprises the following steps: mixing a silicon material 25, a conductive agent, a binder and a gas generating material, adding deionized water, stirring, pulping to obtain a negative electrode slurry, coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21; coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21 and the buffer layer 22; and coating the negative electrode slurry on a copper foil, tabletting, slicing and drying to obtain the copper foil attached with the expansion layer 21, the buffer layer 22 and the protective layer 23 (diaphragm), namely the silicon-containing layered negative electrode plate.
The drying temperature is 85 ℃, and the drying time is 12h.
The rolling pressure required by the first tabletting is 0.13MPa, and the rolling pressures required by the subsequent tabletting for two times are 1.85MPa and 1.95MPa respectively.
1.3 the thickness of one layer of membrane is 0.115mm, the membrane comprises an expansion layer 21, a buffer layer 22 and a protective layer 23, the expansion layer 21, the buffer layer 22 and the protective layer 23 are sequentially in close contact and arranged, the expansion layer 21 is closest to the negative current collector 1, the buffer layer 22 and the protective layer 23 are sequentially far away from the negative current collector 1, and the protective layer 23 is closest to the electrolyte and the isolating membrane;
the hole 24 diameter in inflation layer 21, buffer layer 22, the protective layer 23 reduces in proper order, and the hole 24 volume accounts for and reduces in proper order, and hole 24 is in proper order denser, and protective layer 23, buffer layer 22, the 21 hole 24 diameters of inflation layer more rare in proper order more big, satisfy: 0.018m is more than or equal to K Intumescent layer 2150 ≥K Buffer layer 2250 ≥K Protective layer 2350 ＞0。
The silicon material 25 is a single particle or a composite particle, the micron silicon oxide and the graphite composite material are mixed to obtain a single particle, and a plurality of single particles are polymerized to obtain a composite particle;
the silicon material 25 accounts for 94.2%, 96.7% and 96.1% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23, wherein the mass of the silica in each of the expansion layer 21, the buffer layer 22 and the protective layer 23 accounts for 15.1%, 12.1% and 2.3% of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
The adhesive is prepared from polyacrylonitrile and polyvinylidene fluoride according to a mass ratio of 1:1, the binder respectively accounts for 3%, 1.5% and 3% of the mass of each of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the gas generating material is ammonium fluoride which respectively accounts for 1 percent, 0.6 percent and 0.3 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23;
the conductive agent is prepared from acetylene black and conductive carbon nanotubes in a mass ratio of 8:2, and the conductive agent accounts for 1.8 percent, 1.2 percent and 0.6 percent of the mass of the expansion layer 21, the buffer layer 22 and the protective layer 23 respectively.
2, preparing the lithium ion battery:
a silicon-containing layered negative plate, an isolating film and a positive plate (containing 96.5 percent of lithium iron phosphate LiFePO) 4 Positive electrode active material) to obtain a battery core, sealing and bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Comparative example 1:
1, preparation of a silicon-containing negative plate:
1.1 mechanically stirring and mixing 0.25kg of micron silicon oxide and 4.75kg of graphite to obtain a silicon material 25, and a silicon-containing negative plate, wherein the preparation method of the negative plate comprises the following steps: silicon material 25, a binder (the binder prepared in the above example 2), and a conductive agent (the conductive agent prepared in the above example 2) were mixed in a mass ratio of 96.5:2.5:1 to obtain uniform slurry, uniformly coating the slurry on a copper foil, rolling and tabletting under 1.89MPa, slicing, and drying at 105 ℃ for 6 hours to obtain a layer of membrane with the thickness of 0.128mm, wherein two surfaces of the silicon-containing negative plate are respectively provided with a layer of membrane.
2, preparing the lithium ion battery:
2.1 silicon-containing layered negative plate, isolating film and positive plate (containing 97.5% LiNi-Co-Mn oxide) 0.8 Co 0.1 Mn 0.1 O 2 Positive electrode active material) to obtain a battery core, sealing the battery core, bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: and (3) compacting the density, and obtaining the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the membrane after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Comparative example 2:
1, preparation of a silicon-containing negative plate:
1.1 mechanically stirring and mixing 0.25kg of micron silicon oxide and 4.75kg of graphite to obtain a silicon material 25, and a silicon-containing negative plate, wherein the preparation method of the negative plate comprises the following steps: silicon material 25, a binder (the binder prepared in example 2 above), and a conductive agent (the conductive agent prepared in example 2 above) were mixed in a mass ratio of 97:2.0:1.0, obtaining uniform slurry, uniformly coating the slurry on a copper foil, rolling and tabletting under 1.89MPa, slicing, and drying at 105 ℃ for 6 hours to obtain a layer of membrane with the thickness of 0.123mm, wherein two sides of the silicon-containing negative plate are respectively provided with a layer of membrane.
2, preparing the lithium ion battery:
2.1 silicon-containing layered negative plate, isolating film and positive plate (containing 97.5% LiNi-Co-Mn oxide) 0.8 Co 0.1 Mn 0.1 O 2 Positive electrode active material) to obtain a battery core, sealing the battery core, bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: compacting the density, preparing the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the diaphragm after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Comparative example 3
1, preparation of a silicon-containing negative plate:
1.1 mechanically stirring and mixing 0.15kg of carbon-coated micron silicon material 25 and 4.85kg of graphite to obtain the silicon material 25, and the preparation method of the silicon-containing negative plate comprises the following steps: silicon material 25, a binder (the binder prepared in example 6 above), and a conductive agent (the conductive agent prepared in example 6 above) were mixed in a mass ratio of 96.5:2.0:1.5, uniformly coating the slurry on a copper foil, rolling and tabletting under the pressure of 1.95MPa, slicing, and drying at 85 ℃ for 12 hours to prepare a layer of membrane with the thickness of 0.154mm, wherein two surfaces of the silicon-containing negative plate are respectively provided with a layer of membrane.
2, preparing the lithium ion battery:
2.1 mixing the silicon-containing layered negative plate, the isolating film and the positive plate (containing 97.5 percent of lithium iron phosphate LiFePO) 4 Positive electrode active material) to obtain a battery core, sealing and bundling the battery core, loading the battery core into a battery shell, welding a shell opening, performing vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and grading to obtain the lithium ion battery.
3 the measurement items include: compacting the density, preparing the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the diaphragm after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
Comparative example 4:
1, preparation of a silicon-containing negative plate:
1.1 mechanically stirring and mixing 0.15kg of carbon-coated micron silicon material 25 and 4.85kg of graphite to obtain the silicon material 25, and the preparation method of the silicon-containing negative plate comprises the following steps: silicon material 25, a binder (the binder prepared in example 6 above), and a conductive agent (the conductive agent prepared in example 6 above) were mixed in a mass ratio of 97:2.0:1.0 to obtain uniform slurry, uniformly coating the slurry on a copper foil, rolling and tabletting under 1.95MPa, slicing, and drying at 85 ℃ for 12 hours to obtain a layer of membrane with the thickness of 0.152mm, wherein two surfaces of the silicon-containing negative plate are respectively provided with a layer of membrane.
2, preparing the lithium ion battery:
2.1 mixing the silicon-containing layered negative plate, the isolating film and the positive plate (containing 97.5 percent of lithium iron phosphate LiFePO) 4 Positive electrode active material) to obtain a battery core, sealing the battery core, bundling the battery core, filling the battery core into a battery shell, welding a shell opening, vacuum drying, injecting electrolyte into the battery shell, packaging, standing, forming and dividingAnd (6) obtaining the lithium ion battery.
3 the measurement items include: compacting the density, preparing the capacity retention rate of the lithium ion battery in 1 circle, 20 circles, 100 circles, 500 circles and 1000 circles of cyclic charge and discharge, and observing the surface appearance of the diaphragm after the lithium ion battery is cyclically charged and discharged for 1000 circles by using an electron microscope.
TABLE 1 data of measurement items of examples 1 to 8 and comparative examples 1 to 4
Figure BDA0003772867470000231
Under the condition that the thicknesses and the compaction densities of the membranes of the examples 1 to 8 and the comparative examples 1 to 4 are similar, the capacity retention rates of the lithium ion batteries prepared in the examples 1 to 8 in the cycles 1, 20, 100, 500 and 1000 are obviously better than those of the lithium ion batteries prepared in the comparative examples 1 to 4 in the cycles 1, 20, 100, 500 and 1000, the appearances of the lithium ion batteries Chi Mopian of the examples 1 to 8 are also better than those of the lithium ion batteries Chi Mopian of the comparative examples 1 to 4, and the results show that the examples 1 to 8 have higher dynamic performance of lithium removal and lithium insertion, so that the lithium ion batteries have higher initial coulombic efficiency and better capacity retention rate.
Variations and modifications to the above-described embodiments may also occur to those skilled in the art, which fall within the scope of the invention as disclosed and taught herein. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious modifications, substitutions or alterations based on the present invention will fall within the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims (11)

1. The utility model provides a negative pole piece, its characterized in that includes the negative pole mass flow body and sets up in the diaphragm layer of the at least one surface of negative pole mass flow body, the diaphragm layer includes the raw materials of following parts by weight: 80-98 parts of silicon material, 0.1-5 parts of gas generating material, 1-10 parts of binder and 0.2-8 parts of conductive agent.
2. The negative electrode sheet of claim 1, wherein the membrane layer comprises an expansion layer disposed on the surface of the negative electrode current collector, a buffer layer disposed on a side of the expansion layer away from the negative electrode current collector, and a protection layer disposed on the buffer layer away from the expansion layer.
3. The negative pole piece of claim 1, wherein the membrane layer has a thickness of 0.035 to 0.95mm and a compacted density of 1.05 to 1.90g/cm 3 。
4. The negative electrode sheet of claim 2, wherein the pore diameters of the expansion layer, the buffer layer, and the protective layer satisfy the following relationship: k Intumescent layer 50 ≥K Buffer layer 50 ≥K Protective layer 50 ，K Intumescent layer 50 ≤0.035mm，K Protective layer 50 ＞0。
5. The negative electrode plate of claim 2, wherein the mass ratio of the silicon material in the expansion layer, the buffer layer and the protective layer is 80-98%, the mass ratio of the gas-generating material in the expansion layer, the buffer layer and the protective layer is 0.1-5%, the mass ratio of the binder in the expansion layer, the buffer layer and the protective layer is 1-10%, and the mass ratio of the conductive agent in the expansion layer, the buffer layer and the protective layer is 0.2-8%.
6. The negative pole piece of claim 5, wherein the content of the silicon material in the expansion layer is greater than the content of the silicon material in the buffer layer, and the content of the silicon material in the buffer layer is greater than the content of the silicon material in the protective layer.
7. The negative electrode plate of claim 5, wherein the content of the gas-producing material in the expansion layer is greater than the content of the gas-producing material in the buffer layer and/or the content of the gas-producing material in the expansion layer is greater than the content of the gas-producing material in the protective layer.
8. The negative electrode sheet of claim 5, wherein the binder content in the expansion layer is greater than the binder content in the buffer layer and/or the binder content in the protective layer is greater than the binder content in the buffer layer.
9. The negative electrode sheet of claim 5, wherein the content of the conductive agent in the expansion layer is greater than the content of the conductive agent in the buffer layer and/or the content of the conductive agent in the expansion layer is greater than the content of the conductive agent in the protective layer.
10. The preparation method of the negative electrode plate as claimed in any one of claims 1 to 9, characterized by comprising the following steps:
step S1, mixing a silicon material, a gas generating material, a binder and a conductive agent according to a first proportion, adding a solvent, and stirring to obtain a first negative electrode slurry;
s2, coating the first negative electrode slurry on at least one surface of a negative electrode current collector, and drying to form an expansion layer;
s3, mixing the silicon material, the gas generating material, the binder and the conductive agent according to a second proportion, adding the solvent and stirring to prepare a second cathode slurry;
s4, coating the second cathode slurry on the surface of the expansion layer, and drying to form a buffer layer;
s5, mixing the silicon material, the gas generating material, the binder and the conductive agent according to a third proportion, adding the solvent and stirring to prepare third negative electrode slurry;
and S6, coating the third negative electrode slurry on the surface of the buffer layer, and drying to form a protective layer to obtain the negative electrode piece.
11. A secondary battery comprising the negative electrode sheet according to any one of claims 1 to 9.
CN202210907036.2A 2022-07-29 2022-07-29 Negative pole piece, preparation method thereof and secondary battery Pending CN115295764A (en)

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Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101894940A (en) * 2010-08-03 2010-11-24 哈尔滨工业大学 Porous silicon-based cathode for lithium battery and preparation method thereof
CN102769121A (en) * 2012-06-29 2012-11-07 深圳市海太阳实业有限公司 Silicon-carbon negative pole piece, manufacturing method thereof, lithium ion battery and manufacturing method thereof
CN103515607A (en) * 2012-06-27 2014-01-15 比亚迪股份有限公司 Negative electrode slurry of lithium ion battery, positive electrode of lithium ion battery prepared by slurry and battery
CN103633298A (en) * 2012-08-28 2014-03-12 华为技术有限公司 Lithium ion battery silicon negative electrode sheet and preparation method thereof, and lithium ion battery
CN103811719A (en) * 2012-11-09 2014-05-21 华为技术有限公司 Lithium ion battery silicon negative electrode plate and its preparation method and lithium ion battery
CN104538584A (en) * 2014-12-03 2015-04-22 惠州市恒泰科技有限公司 Multilayer cathode sheet, method for producing cathode sheet and lithium ion battery
CN108258323A (en) * 2018-01-30 2018-07-06 陕西煤业化工技术研究院有限责任公司 A kind of production method of high specific energy solid lithium battery
CN108550857A (en) * 2018-03-15 2018-09-18 桑顿新能源科技有限公司 A kind of negative plate and lithium battery with gradient silicone content
CN108767195A (en) * 2018-04-27 2018-11-06 国联汽车动力电池研究院有限责任公司 A kind of adjustable silicon based electrode of pore structure and preparation method thereof
CN110350238A (en) * 2019-07-03 2019-10-18 中兴高能技术有限责任公司 A kind of all-solid lithium-ion battery and preparation method thereof with porous gradient-structure
CN110534702A (en) * 2018-05-26 2019-12-03 深圳格林德能源有限公司 A kind of lithium ion battery silicon negative electrode tab
CN111584826A (en) * 2020-05-21 2020-08-25 徐州凌云硅业股份有限公司 High-capacity lithium ion battery silicon negative electrode material and preparation method thereof
CN112103469A (en) * 2020-09-22 2020-12-18 傲普(上海)新能源有限公司 Silicon-carbon negative electrode plate, preparation method thereof and lithium ion battery
CN114079048A (en) * 2020-08-18 2022-02-22 比亚迪股份有限公司 Negative pole piece and lithium ion battery

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101894940A (en) * 2010-08-03 2010-11-24 哈尔滨工业大学 Porous silicon-based cathode for lithium battery and preparation method thereof
CN103515607A (en) * 2012-06-27 2014-01-15 比亚迪股份有限公司 Negative electrode slurry of lithium ion battery, positive electrode of lithium ion battery prepared by slurry and battery
CN102769121A (en) * 2012-06-29 2012-11-07 深圳市海太阳实业有限公司 Silicon-carbon negative pole piece, manufacturing method thereof, lithium ion battery and manufacturing method thereof
CN103633298A (en) * 2012-08-28 2014-03-12 华为技术有限公司 Lithium ion battery silicon negative electrode sheet and preparation method thereof, and lithium ion battery
CN103811719A (en) * 2012-11-09 2014-05-21 华为技术有限公司 Lithium ion battery silicon negative electrode plate and its preparation method and lithium ion battery
CN104538584A (en) * 2014-12-03 2015-04-22 惠州市恒泰科技有限公司 Multilayer cathode sheet, method for producing cathode sheet and lithium ion battery
CN108258323A (en) * 2018-01-30 2018-07-06 陕西煤业化工技术研究院有限责任公司 A kind of production method of high specific energy solid lithium battery
CN108550857A (en) * 2018-03-15 2018-09-18 桑顿新能源科技有限公司 A kind of negative plate and lithium battery with gradient silicone content
CN108767195A (en) * 2018-04-27 2018-11-06 国联汽车动力电池研究院有限责任公司 A kind of adjustable silicon based electrode of pore structure and preparation method thereof
CN110534702A (en) * 2018-05-26 2019-12-03 深圳格林德能源有限公司 A kind of lithium ion battery silicon negative electrode tab
CN110350238A (en) * 2019-07-03 2019-10-18 中兴高能技术有限责任公司 A kind of all-solid lithium-ion battery and preparation method thereof with porous gradient-structure
CN111584826A (en) * 2020-05-21 2020-08-25 徐州凌云硅业股份有限公司 High-capacity lithium ion battery silicon negative electrode material and preparation method thereof
CN114079048A (en) * 2020-08-18 2022-02-22 比亚迪股份有限公司 Negative pole piece and lithium ion battery
CN112103469A (en) * 2020-09-22 2020-12-18 傲普(上海)新能源有限公司 Silicon-carbon negative electrode plate, preparation method thereof and lithium ion battery

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
郑仕琦: "高比容量硅碳负极的电极结构构筑", 《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》, pages 32 - 52 *

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