CN110931718B - Lithium paste and preparation method and application thereof - Google Patents

Lithium paste and preparation method and application thereof Download PDF

Info

Publication number
CN110931718B
CN110931718B CN201811099653.4A CN201811099653A CN110931718B CN 110931718 B CN110931718 B CN 110931718B CN 201811099653 A CN201811099653 A CN 201811099653A CN 110931718 B CN110931718 B CN 110931718B
Authority
CN
China
Prior art keywords
lithium
paste
carbon
lithium paste
solvent
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201811099653.4A
Other languages
Chinese (zh)
Other versions
CN110931718A (en
Inventor
孔德钰
陈强
牟瀚波
王亚龙
刘承浩
郇庆娜
孙清海
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhongneng Zhongke Tianjin New Energy Technology Co ltd
Original Assignee
Zhongneng Zhongke Tianjin New Energy Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhongneng Zhongke Tianjin New Energy Technology Co ltd filed Critical Zhongneng Zhongke Tianjin New Energy Technology Co ltd
Priority to CN201811099653.4A priority Critical patent/CN110931718B/en
Publication of CN110931718A publication Critical patent/CN110931718A/en
Application granted granted Critical
Publication of CN110931718B publication Critical patent/CN110931718B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/364—Composites as mixtures
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/381—Alkaline or alkaline earth metals elements
    • H01M4/382—Lithium
    • 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
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • 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
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • 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
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • 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

Abstract

The invention provides a lithium paste and a preparation method and application thereof. The lithium paste comprises 20-70% of metal lithium-skeleton carbon composite particles, 20-70% of solvent, 2-50% of passivator, 5-60% of binder and 0-30% of conductive agent. The lithium paste does not generate heat and self-ignite when exposed in the air, can be used for coating, and solves the problems of safe storage, use and transportation of active metal lithium-framework carbon composite particles. When the lithium paste is applied to a battery, on one hand, a passivating agent in the lithium paste is used as a negative artificial protective layer to effectively inhibit continuous interface reaction between electrolyte and metal lithium; on the other hand, the electrode prepared by coating the lithium paste has a multidimensional conduction path of electrons and ions, so that the volume change in the electrode circulation process can be effectively relieved, and the cycle life of the battery is prolonged.

Description

Lithium paste and preparation method and application thereof
Technical Field
The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium paste and a preparation method and application thereof.
Background
The lithium ion battery is widely applied to the fields of 3C, new energy automobiles and the like as a secondary battery. However, with the continuous improvement of the requirement of people on the endurance capacity of equipment, the energy density (200 Wh/kg-300 Wh/kg) of the existing lithium ion battery cannot meet the requirement of higher energy density, so people have great interest in high specific capacity electrode materials.
The metallic lithium has a low density (0.534 g/cm)3) The highest theoretical capacity (3860mAh/g) and the lowest electrochemical potential (-3.04V vers standard hydrogen electrode) have been the hot spots of research. At present, metallic lithium is mainly used for negative electrode lithium supplement, lithium sulfur batteries and all-solid-state batteries. The ideal lithium supplementing mode of the negative electrode is to carry out homogenate coating on lithium powder and a negative electrode active substance together, so that the consistency of lithium supplementing can be ensured, but metal lithium is taken as a first main group element, has active chemical property, particularly has large specific surface area, namely exists in a powdery form, has extremely high activity, is easy to have violent reaction with water and oxygen in the air, and the extremely high reaction activity of the metal lithium powder greatly limits the application range of the metal lithium powder. The preparation and use processes of the lithium powder generally require to be carried out in a glove box protected by argon atmosphere, and the storage and transportation of the lithium powder require argon protection and sealing.
In addition, when the metal lithium is used for lithium-sulfur batteries and all-solid-state batteries, the volume of the electrode changes along with the circulation, and the main reason is that metal lithium dendrites are formed in the deposition process of the metal lithium electrode, the dendrites are broken and stacked to form 'dead lithium', and finally the electrode expands and atomizes.
In view of the above deficiencies, there is a need for a lithium metal product that is stable, safe, and reduces dendrite growth.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to: provides the lithium paste which is safe and stable and can be produced in batch. The lithium paste is simple and convenient to prepare, safe to operate and convenient to transport and store; in addition, the lithium paste is used as the negative active material, so that the expansion of the negative electrode can be relieved, the growth of lithium dendrites can be reduced, and the cycling stability of the electrode can be improved.
In order to achieve the purpose, the invention adopts the following technical scheme:
one aspect of the present invention provides a lithium paste comprising 20 to 70 mass% of metallic lithium-skeletal carbon composite fine particles, 20 to 70 mass% of a solvent, 2 to 50 mass% of a passivating agent, 5 to 60 mass% of a binder, and 0 to 30 mass% of a conductive agent.
Preferably, the lithium paste comprises 20-50% by mass of metallic lithium-skeletal carbon composite particles, 20-50% by mass of a solvent, 2-30% by mass of a passivating agent, 5-35% by mass of a binder and 2-20% by mass of a conductive agent.
In some embodiments, the lithium paste has a viscosity of 3000mPa · s to 100000mPa · s at a temperature of 25 ℃.
In some embodiments, the lithium metal-framework carbon composite fine particles include a porous framework carbon support having pores with an average pore diameter of 10 to 100nm, and lithium metal distributed at least in the pores of the porous framework carbon support, and the lithium metal-framework carbon composite fine particles have an average diameter of 1 to 50 μm.
In some embodiments, the material of the skeletal carbon support includes any one or a combination of two or more of carbon nanotube microspheres, porous carbon microspheres, carbon black microspheres, graphene microspheres, carbon fiber microspheres, acetylene black microspheres, and carbon aerogel microspheres.
In some embodiments, the solvent comprises C5-C20 alkanes, C5-C10 cycloalkanes, C5-C10 ethers, benzenes, and C2-C15 saturated heterocyclic solvents, with preferred solvents comprising p-xylene, acetonitrile, tetrahydrofuran, dimethyl carbonate, dioxolane, n-hexane, cyclohexane.
In some embodiments, the passivating agent comprises a material comprising lithium-philic groups, such as phosphoric acid; or a substance containing a lithium-philic group and a hydrophobic group, such as octadecyl phosphate; wherein the lithium-philic group comprises at least one of a phosphate group, a thiol group, a carbonate group, and an optionally fluorinated silane group; the hydrophobic group comprises at least one of a C4-C22 alkyl group, a C6-C24 aryl group, and a siloxane group, which groups are optionally substituted with a hydrophobic substituent.
In some embodiments, the binder comprises: polyacrylic acid (PAA), polyvinylidene fluoride (PVDF), polyethylene oxide (PEO), ethylene-propylene-copolymer (EPM), polybutylene (PP), ethylene-vinyl acetate copolymer (EVM), and at least one of rubber-based polymers such as Natural Rubber (NR), Butadiene Rubber (BR), ethylene-propylene-diene rubber (EPDM), styrene-butadiene rubber (SBR), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), epichlorohydrin rubber (ECO), acrylate rubber (ACM), and silicone rubber (SI).
In some embodiments, the conductive agent comprises: at least one of carbon nanotubes, carbon nanofibers, conductive carbon black, acetylene black, ketjen black, conductive polymers, metal fibers, and metal particles.
Another aspect of the present invention provides a method for preparing a lithium paste, including: firstly, dissolving a binder in a solvent, then adding a metal lithium-framework carbon material composite particle, a passivating agent and an optional conductive agent into the solvent, or dissolving the binder and the passivating agent into the solvent, then adding the metal lithium-framework carbon material composite particle and the optional conductive agent into the solvent, and stirring for 1-6 hours under a protective atmosphere to obtain a lithium paste, wherein the mass fractions of the metal lithium-framework carbon composite particle, the solvent, the passivating agent, the binder and the conductive agent are respectively 20-70%, 2-50%, 5-60% and 0-30%. Preferably, the protective atmosphere comprises an inert gas atmosphere, such as argon or other inert gas.
Another aspect of the invention provides the use of a lithium paste comprising applying a lithium paste according to the above on a surface of a negative electrode, a surface of a metal current collector, or a surface of a separator, or a surface of a solid electrolyte of a lithium battery.
Preferably, the metal current collector comprises copper, nickel, stainless steel or metallic lithium and a current collector compounded by the copper, the nickel, the stainless steel or the metallic lithium.
Drawings
FIG. 1 is a photograph of a lithium paste obtained according to a preparation example of the present invention coated on a lithium layer of a lithium copper composite tape;
FIG. 2 is an SEM photograph of a lithium paste coated on a lithium copper composite tape according to a preparation example of the present invention;
FIG. 3 shows the results of examples 1 to 3Cycling test curve of the cell (cycling current 5.6 mA/cm)2The circulation capacity is 2.8mAh/cm2)；
Fig. 4 is a photograph of a disassembled lithium plate cell of example 1.
Detailed Description
The lithium paste proposed by the present invention, its preparation method and its use are further described below with reference to specific embodiments, but the method of the present invention is not limited to the following examples.
Preparation of example 1
The lithium paste is prepared by using Paraxylene (PX) as solvent, Styrene Butadiene Rubber (SBR) and Polystyrene (PS) as binder, and phosphoric acid (H)3PO4) As a passivating agent, acetylene black is used as a conductive agent. 5g of styrene-butadiene rubber (SBR), 5g of Polystyrene (PS) and 5g of phosphoric acid crystals (H) are reacted under argon protection3PO4) Dissolved in a beaker containing 60ml of Paraxylene (PX). The magneton was added to the beaker and stirred at 3000rpm using a magnetic stirrer for 6 hours. After styrene butadiene rubber, polystyrene and phosphoric acid crystals were dissolved, 5g of acetylene black and 90g of metallic lithium-skeletal carbon composite particles (prepared according to example 3 of chinese patent application CN 201410395114.0) were added, and 20ml of p-xylene (PX) was added, and high-speed stirring was continued for 4 hours to obtain a lithium paste S1, and the viscosity of the lithium paste was measured at 25 ℃ and the stability of the coated coating at room temperature was observed.
Preparation of example 2
Styrene Butadiene Rubber (SBR) is used as a binder, n-hexane is used as a solvent, octadecyl phosphate is used as a passivating agent, and Ketjen black is used as a conductive agent in the preparation of the lithium paste. Under the protection of argon, 20g of styrene-butadiene rubber (SBR) was dissolved in a beaker containing 100ml of n-hexane, magnetons were added to the beaker, stirring was carried out at 2500rpm using a magnetic stirrer, after the styrene-butadiene rubber was dissolved, 5g of octadecyl phosphate, 5g of Ketjen black and 90g of metallic lithium-skeletal carbon composite fine particles (prepared according to example 3 of Chinese patent application CN 201410395114.0) were added, high-speed stirring was continued for 2 hours to obtain a lithium paste S2, the viscosity of the lithium paste was measured at a temperature of 25 ℃ and the stability of the coated coating at room temperature was observed.
Preparation of example 3
The lithium paste is prepared by using Paraxylene (PX) as solvent, Polystyrene (PS) as binder, and phosphoric acid (H)3PO4) As a passivating agent, carbon nanotubes are used as a conductive agent. Under the protection of argon, 15g of styrene-butadiene rubber (SBR), 10g of Polystyrene (PS) and 5g of phosphoric acid crystal (H)3PO4) Dissolved in a beaker containing 60ml of Paraxylene (PX). Magnetons were added to the beaker and stirred at 3500rpm using a magnetic stirrer. After styrene-butadiene rubber and polystyrene were dissolved, 5g of carbon nanotube conductive agent and 90g of metal lithium-skeletal carbon composite particles (prepared according to example 3 of chinese patent application CN 201410395114.0) were added, and 20ml of p-xylene (PX) was added, and high-speed stirring was continued for 4 hours to obtain a lithium paste S3, and the viscosity of the lithium paste was measured at 25 ℃ and the stability of the coated coating at room temperature was observed.
Preparation of example 4
Styrene Butadiene Rubber (SBR) is used as a binder, a mixed solution of n-hexane and Tetrahydrofuran (THF) is used as a solvent, octadecyl phosphate is used as a passivating agent, and carbon nano tubes are used as a conductive agent when the lithium paste is prepared. 10g of styrene-butadiene rubber (SBR) was dissolved in a beaker containing 150ml of a mixture of n-hexane and Tetrahydrofuran (THF) in a volume ratio of 1:1 under the protection of argon. Adding magnetons into a beaker, stirring at 3500rpm by using a magnetic stirrer, adding 5g of octadecyl phosphate, 5g of carbon nanotubes and 90g of metallic lithium-skeletal carbon composite particles (prepared according to example 3 of chinese patent application CN 201410395114.0) after styrene butadiene rubber is dissolved, continuing to stir at high speed for 3 hours to obtain lithium paste S4, measuring the viscosity of the lithium paste at a temperature of 25 ℃ and observing the stability of the coated coating at room temperature.
Preparation of example 5
The preparation method of the lithium paste comprises the steps of using Styrene Butadiene Rubber (SBR) and Polystyrene (PS) as binders, using a mixed solution of n-hexane and Tetrahydrofuran (THF) as a solvent, and using phosphoric acid crystals (H)3PO4) As a passivating agent, conductive carbon black is used as a conductive agent. 50g of Styrene Butadiene Rubber (SBR) and 50g of Polystyrene (PS) were dissolved in a steel drum containing 250ml of a mixture of n-hexane and Tetrahydrofuran (THF) under an argon atmosphere (volume of n-hexane and Tetrahydrofuran (THF))The ratio is 3: 1). After styrene-butadiene rubber was dissolved, 10g of phosphoric acid crystals, 10g of conductive carbon black and 200g of metallic lithium-skeletal carbon composite fine particles (prepared according to example 3 of chinese patent application CN 201410395114.0) were added thereto by stirring at 5000rpm using a high-speed dispersing apparatus, and high-speed stirring was continued for 4 hours to obtain a lithium paste S5, and the viscosity of the lithium paste was measured at 25 ℃ and the stability of the coated coating at room temperature was observed.
Preparation of example 6
The lithium paste is prepared by using Paraxylene (PX) as solvent, Styrene Butadiene Rubber (SBR) and Polystyrene (PS) as binder, and phosphoric acid (H)3PO4) As a passivating agent, acetylene black is used as a conductive agent. 5g of styrene-butadiene rubber (SBR), 5g of Polystyrene (PS) and 5g of phosphoric acid crystals (H) are reacted under argon protection3PO4) Dissolved in a beaker containing 60ml of Paraxylene (PX). The magneton was added to the beaker and stirred at 3000rpm using a magnetic stirrer for 6 hours. After styrene butadiene rubber, polystyrene and phosphoric acid crystals are dissolved, 5g of acetylene black and 90g of lithium powder (the particle size of the lithium powder is 50 microns) are added, 20ml of p-xylene (PX) is added, high-speed stirring is continued for 4 hours to obtain lithium paste S6, the viscosity of the lithium paste is measured at the temperature of 25 ℃, and the stability of the coated coating at room temperature is observed.
Comparative example 1
The lithium paste is prepared by using Paraxylene (PX) as solvent, Styrene Butadiene Rubber (SBR) and Polystyrene (PS) as binder, and phosphoric acid (H)3PO4) As a passivating agent, acetylene black is used as a conductive agent. 5g of styrene-butadiene rubber (SBR), 5g of Polystyrene (PS) and 2g of phosphoric acid crystals (H) are reacted under argon protection3PO4) Dissolved in a beaker containing 60ml of Paraxylene (PX). The magneton was added to the beaker and stirred at 3000rpm using a magnetic stirrer for 6 hours. After styrene butadiene rubber, polystyrene and phosphoric acid crystals were dissolved, 5g of acetylene black and 90g of metallic lithium-skeletal carbon composite particles (prepared according to example 3 of chinese patent application CN 201410395114.0) were added, and 20ml of p-xylene (PX) was added, and high-speed stirring was continued for 4 hours to obtain a lithium paste C1, and the viscosity of the lithium paste was measured at 25 ℃ and the stability of the coated coating at room temperature was observed.
Comparative example 2
The lithium paste is prepared by using Paraxylene (PX) as a solvent, Styrene Butadiene Rubber (SBR) and Polystyrene (PS) as a binder, and acetylene black as a conductive agent. 5g of Styrene Butadiene Rubber (SBR) and 5g of Polystyrene (PS) were dissolved in a beaker containing 60ml of p-xylene (PX) under argon protection. The magneton was added to the beaker and stirred at 3000rpm using a magnetic stirrer for 6 hours. After styrene butadiene rubber, polystyrene and phosphoric acid crystals were dissolved, 5g of acetylene black and 90g of metallic lithium-skeletal carbon composite particles (prepared according to example 3 of chinese patent application CN 201410395114.0) were added, and 20ml of p-xylene (PX) was added, and high-speed stirring was continued for 4 hours to obtain a lithium paste C2, and the viscosity of the lithium paste was measured at 25 ℃ and the stability of the coated coating at room temperature was observed.
Comparative example 3
The lithium paste is prepared by using p-xylene (PX) as solvent and phosphoric acid (H)3PO4) As a passivating agent, acetylene black is used as a conductive agent. 5g of phosphoric acid crystals (H) are added under argon protection3PO4) Dissolved in a beaker containing 60ml of Paraxylene (PX). The magneton was added to the beaker and stirred at 3000rpm using a magnetic stirrer for 6 hours. After styrene butadiene rubber, polystyrene and phosphoric acid crystals were dissolved, 5g of acetylene black and 90g of metallic lithium-skeletal carbon composite particles (prepared according to example 3 of chinese patent application CN 201410395114.0) were added, and 20ml of p-xylene (PX) was added, and high-speed stirring was continued for 4 hours to obtain a lithium paste C3, and the viscosity of the lithium paste was measured at 25 ℃ and the stability of the coated coating at room temperature was observed.
TABLE 1 comparison of the viscosity of the lithium pastes and the stability of the coatings at room temperature in the examples
Sample numbering Content of deactivators/%) Content of binder/%) viscosity/mPas Stability of
S1 3％ 6％ 7500 No heat generation and no spontaneous combustion
S2 3％ 11％ 8000 No heat generation and no spontaneous combustion
S3 3％ 13％ 9500 No heat generation and no spontaneous combustion
S4 2％ 5％ 5500 No heat generation and no spontaneous combustion
S5 2％ 21％ 32000 No heat generation and no spontaneous combustion
S6 3％ 6％ 7500 Generate heat and spontaneously combust after encountering air for 3 seconds
C1 1％ 6％ 7500 Generate heat and spontaneously combust after meeting air for 60 seconds
C2
0％ 6％ 7200 Generate heat and spontaneously combust in air for 3 seconds
C3 3％ 0％ 2500 No heat generation and no spontaneous combustion
Comparative example 3 shows that the viscosity of the lithium paste was very low, about 2500 mPas, without adding a binder, and the minimum viscosity of 3000 mPas required for the lithium paste was not achieved. Comparative example 1 and comparative example 2 show that the lithium paste can be coated without adding a passivating agent in the process of preparing the lithium paste, but the lithium paste has poor stability in air, is easy to generate heat and spontaneously ignites after encountering air for 3 seconds; comparative examples 1 to 5 have found that a proper amount of a passivating agent is added during the preparation of a lithium paste to ensure the stability of the operation of the lithium paste. A small amount of passivating agent, comparative example 1, only slightly improved the stability of the lithium paste, which spontaneously ignited after standing in air for 60 seconds; when the content of the passivating agent exceeds 2 percent, the lithium paste does not generate heat and self-ignite at room temperature.
In addition, when lithium powder was used for production, that is, preparation example 6, the coated coating layer was hot despite the addition of 3% of the passivating agent, and spontaneous combustion occurred after 3 seconds in the presence of air. Compared with the preparation example 1, the lithium powder is difficult to passivate and poor in safety under the condition that the passivating agent proportion is the same, and the metal lithium-skeleton carbon composite particles are easier to passivate, so that the safety and operability after the lithium paste is prepared are better.
The prepared lithium paste can be coated on the surfaces of copper, nickel, stainless steel and metal lithium current collectors, or the surfaces of diaphragms and solid electrolytes. FIG. 1 is a photograph showing that a lithium paste is coated on a lithium layer of a lithium copper composite tape, and it can be seen from the photograph that the lithium paste can be coated during a drying period, and spontaneous combustion does not occur, and safety is high; fig. 2 is an SEM photograph of the lithium layer of the lithium paste-coated lithium copper composite tape, and it can be seen from fig. 2 that the size of the spherical lithium metal-skeleton carbon composite particles is about 10 μm, and they are closely adhered to the lithium layer, indicating that the lithium paste has strong compatibility with the lithium layer. The use of lithium paste is further illustrated by the following specific examples.
Example 1
In a drying room with a dew point of-45 ℃, a 100-micron lithium-copper composite tape (Likeda, Technida, Shenzhen, Kezhi) is die-cut into pole pieces with the size of 57mm × 44mm by using an MSK-180 semi-automatic die-cutting machine (Likeda, Technida, Shenzhen). And assembling the single sheet to the single sheet of the soft package battery by using the die-cut pole piece, and using the die-cut pole piece for the counter electrode. Manually laminating the pole pieces, placing the pole pieces into an aluminum plastic bag for top side sealing, then placing the pole pieces into a vacuum oven for baking, and preparing the lithium ion battery by the procedures of adding electrolyte, standing, forming, secondary packaging, degassing and the like, wherein the battery is marked as B1. The electrolyte is 1mol/L LiPF6 three-component mixed solvent EC: DMC: EMC 1:1:1 (volume ratio v/v/v), and the polypropylene microporous film is a diaphragm.
Example 2
A lithium paste was prepared according to the above preparation example 1.
In a drying cabinet with a dew point of-45 deg.C, a lithium paste was drawn down to a thickness of 100 μm on a lithium copper composite tape, the coating thickness being approximately 50 μm. And (3) putting the coated lithium-copper composite strip into a vacuum oven for baking at the baking temperature of 80 ℃ for 4 hours.
In a drying room with a dew point of-45 ℃, a lithium copper composite tape (Likeda, Techni, Inc. in Tianjin) coated with lithium paste was die-cut into pole pieces with dimensions of 57mm × 44mm using an MSK-180 semi-automatic die-cutting machine (Shenzhen, Kezhida, Inc.). And assembling the single-piece soft package battery to the single-piece soft package battery by using the die-cut pole pieces, wherein the pole piece coated with the lithium paste is used as a working electrode, and the counter electrode is a lithium copper composite belt pole piece which is not coated with the lithium paste. Manually laminating the pole pieces, placing the pole pieces into an aluminum plastic bag for top side sealing, then placing the pole pieces into a vacuum oven for baking, and preparing the lithium ion battery by the procedures of adding electrolyte, standing, forming, secondary packaging, degassing and the like, wherein the battery is marked as B2. The electrolyte is 1mol/L LiPF6 three-component mixed solvent EC: DMC: EMC 1:1:1 (volume ratio v/v/v), the polypropylene microporous film is used as a diaphragm, and the lithium metal is used as a counter electrode to assemble a button cell, wherein the cell is marked as B2.
Example 3
A lithium paste was prepared according to the above preparation example 1.
In a drying room with a dew point of-45 deg.C, a lithium paste was applied by scraping to PEO (manufactured by SigmaAldrich, molecular weight M)w600,000) film, the thickness of the lithium paste coating was 50 μm. And (3) putting the coated PEO membrane into a vacuum oven to be dried, wherein the baking temperature is 60 ℃, and the baking time is 10 hours. In a drying room with dew point of-45 ℃, the PEO solid electrolyte coated with the lithium paste was sandwiched between the lithium layers of the two lithium copper composite tapes, and the PEO film coated with the lithium paste was die-cut into pole pieces with dimensions of 57mm × 44mm using an MSK-180 semi-automatic die cutter (Shenzhen, science and technology Co., Ltd.). And putting the die-cut pole piece into an aluminum plastic bag for top side sealing, then putting the pole piece into a vacuum oven for baking, and preparing the lithium ion battery by the working procedures of adding electrolyte, standing, forming, secondary packaging, degassing and the like, wherein the battery is marked as B3.
And (2) carrying out cycle test on the batteries B1, B2 and B3 at the temperature of 25 ℃, wherein the cycle steps are as follows: standing for 5 hours, charging at constant current for 0.5 hour, discharging at constant current for 0.5 hour, and circulating current of5.6mA/cm2The circulation capacity is 2.8mAh/cm2. The cycle data of batteries B1, B2 and B3 correspond to B1, B2 and B3 in fig. 3, respectively. B1 in fig. 3 is a curve of the pole piece cycling without applying the lithium paste, and it can be seen from the graph that the polarization voltage of the working electrode is rapidly increased after 100 hours of cycling, which shows that dendrite and "dead lithium" are continuously formed on the electrode surface with the cycling of the electrode, and the performance of the electrode is rapidly deteriorated. The pouch cells were disassembled in a glove box and the electrode surface was found to be stained with gray "dead lithium" and the electrode was severely chalked as shown in fig. 4. Fig. 3B 2 shows a cycle curve of the battery with the lithium-copper composite tape coated with the lithium paste, and it can be seen from the cycle curve that the polarization voltage of the battery is stable after 168 hours of cycles, and there is no significant change, which indicates that the surface of the electrode does not change much during the battery cycle, because the three-dimensional framework carbon structure can provide sites for dendrite deposition, reduce the generation of dendrites, and the three-dimensional framework structure can buffer the change of the electrode volume. The polarization voltage does not change greatly at the later stage of the cycle, and the stability of the structure of the composite particles of the framework material and lithium and the surface Solid Electrolyte Interface (SEI) layer during the cycle is proved. In fig. 3, B3 is a battery cycling curve of lithium paste coated on a solid electrolyte PEO, and it can be seen from the curve that after 100 hours of electrode cycling, the polarization voltage begins to increase, and the cycling performance is obviously better than that of a B1 battery, which indicates that the solid electrolyte coated with lithium paste is beneficial to the electrode cycling performance, and can improve the contact between the solid electrolyte and the electrode and the interface stability between the electrode and the solid electrolyte.
It should be understood that the above-mentioned embodiments are merely preferred embodiments of the present invention, and not intended to limit the present invention, and any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (12)

1. A lithium paste characterized by: the lithium paste comprises 20-70% of metal lithium-skeleton carbon composite particles, 20-70% of solvent, 2-50% of passivator, 5-60% of binder and 0-30% of conductive agent;
wherein the metallic lithium-skeleton carbon composite fine particles include a porous skeleton carbon support and metallic lithium distributed at least in pores of the porous skeleton carbon support, the porous skeleton carbon support has pores having an average pore diameter of 10 to 100nm, and the metallic lithium-skeleton carbon composite fine particles have an average diameter of 1 to 50 μm;
the solvent comprises at least one of C5-C20 alkanes, C5-C10 cycloalkanes, C5-C10 ethers, benzenes and C2-C15 saturated heterocyclic solvents;
the passivating agent comprises a substance containing a lithium-philic group; or a substance containing both a lithium-philic group and a hydrophobic group.
2. The lithium paste according to claim 1, characterized in that: the lithium paste comprises 20-50% by mass of metallic lithium-skeleton carbon composite particles, 20-50% by mass of a solvent, 2-30% by mass of a passivating agent, 5-35% by mass of a binder and 2-20% by mass of a conductive agent.
3. The lithium paste according to claim 1, characterized in that: the viscosity of the lithium paste is 3000 mPas-100000 mPas at 25 ℃.
4. The lithium paste according to claim 1, characterized in that: the material of the skeleton carbon carrier comprises any one or the combination of more than two of carbon nano tube microspheres, porous carbon microspheres, carbon black microspheres, graphene microspheres, carbon fiber microspheres, acetylene black microspheres and carbon aerogel microspheres.
5. The lithium paste according to claim 1, characterized in that: the solvent comprises at least one of p-xylene, acetonitrile, tetrahydrofuran, dimethyl carbonate, dioxolane, n-hexane and cyclohexane.
6. The lithium paste according to claim 1, characterized in that: the lithium-philic group comprises at least one of a phosphoric acid group, a thiol group, a carbon acid group, and an optionally fluorinated silane group; the hydrophobic group comprises at least one of a C4-C22 alkyl group, a C6-C24 aryl group, and a siloxane group, which groups are optionally substituted with a hydrophobic substituent.
7. The lithium paste according to claim 1, characterized in that: the adhesive comprises: at least one of polyacrylic acid (PAA), polyvinylidene fluoride (PVDF), polyethylene oxide (PEO), ethylene-propylene-copolymer (EPM), polybutylene (PP), ethylene-vinyl acetate copolymer (EVM), and rubber-based polymer.
8. The lithium paste according to claim 7, characterized in that: the rubber-based polymer includes at least one of Natural Rubber (NR), Butadiene Rubber (BR), Ethylene Propylene Diene Monomer (EPDM), styrene-butadiene rubber (SBR), Nitrile Butadiene Rubber (NBR), Hydrogenated Nitrile Butadiene Rubber (HNBR), epichlorohydrin rubber (ECO), acrylate rubber (ACM), and silicone rubber (SI).
9. The lithium paste according to claim 1, characterized in that: the conductive agent includes: at least one of carbon nanotubes, carbon nanofibers, conductive carbon black, acetylene black, ketjen black, conductive polymers, metal fibers, and metal particles.
10. A method of making the lithium paste of any one of claims 1-9, comprising: firstly, dissolving a binder in a solvent, and then adding the metal lithium-skeleton carbon material composite particles, a passivating agent and an optional conductive agent into the solvent; or dissolving the binder and the passivating agent in a solvent, adding the metal lithium-skeleton carbon material composite particles and the optional conductive agent into the solvent, and stirring for 1-6 hours in a protective atmosphere to obtain the lithium paste, wherein the mass fractions of the metal lithium-skeleton carbon composite particles, the solvent, the passivating agent, the binder and the conductive agent are 20-70%, 2-50%, 5-60% and 0-30%, respectively.
11. Use of a lithium paste comprising applying the lithium paste according to any one of claims 1 to 9 to a negative electrode surface, or a metal current collector surface, or a separator surface, or a solid electrolyte surface of a lithium battery.
12. Use according to claim 11, characterized in that: the metal current collector comprises copper, nickel, stainless steel or metal lithium and a current collector compounded by the copper, the nickel, the stainless steel or the metal lithium.
CN201811099653.4A 2018-09-20 2018-09-20 Lithium paste and preparation method and application thereof Active CN110931718B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811099653.4A CN110931718B (en) 2018-09-20 2018-09-20 Lithium paste and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811099653.4A CN110931718B (en) 2018-09-20 2018-09-20 Lithium paste and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN110931718A CN110931718A (en) 2020-03-27
CN110931718B true CN110931718B (en) 2021-06-08

Family

ID=69856179

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811099653.4A Active CN110931718B (en) 2018-09-20 2018-09-20 Lithium paste and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN110931718B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113745682A (en) * 2020-05-27 2021-12-03 天津中能锂业有限公司 Method for disassembling lithium metal cathode from lithium battery
CN111933951B (en) * 2020-08-25 2021-10-15 中南大学 Lithium metal active precursor material and preparation and application thereof
CN113299887B (en) * 2021-05-20 2022-09-16 清华大学深圳国际研究生院 Preparation method of metal lithium negative electrode, metal lithium negative electrode and lithium metal battery

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104925778A (en) * 2014-03-21 2015-09-23 中国科学院苏州纳米技术与纳米仿生研究所 Carbon nanotube microsphere and preparation method and application thereof
CN105789559A (en) * 2016-04-21 2016-07-20 清华大学 Flexible lithium metal cell negative pole and preparation method thereof
WO2017025254A1 (en) * 2015-08-07 2017-02-16 Robert Bosch Gmbh Mof silicon-carbon composite anode material
CN106711456A (en) * 2015-11-12 2017-05-24 中国科学院苏州纳米技术与纳米仿生研究所 Passivated lithium metal-carbon skeleton composite material and preparation method and application thereof
CN107305941A (en) * 2016-04-21 2017-10-31 中国科学院苏州纳米技术与纳米仿生研究所 Lithium carbon composite, its preparation method and application and lithium compensation method
CN108539185A (en) * 2018-05-24 2018-09-14 中南大学 A kind of lithium or anode material of lithium-ion battery and preparation method thereof

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104409224A (en) * 2013-11-28 2015-03-11 东莞市长安东阳光铝业研发有限公司 Cathode plate for lithium-ion capacitor and production method of cathode plate
KR20180094134A (en) * 2016-01-13 2018-08-22 어플라이드 머티어리얼스, 인코포레이티드 Anode structure with binders for silicon and stabilized lithium metal powder
CN108428564A (en) * 2017-02-14 2018-08-21 东莞东阳光科研发有限公司 A kind of preparation method of lithium-ion capacitor negative plate

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104925778A (en) * 2014-03-21 2015-09-23 中国科学院苏州纳米技术与纳米仿生研究所 Carbon nanotube microsphere and preparation method and application thereof
WO2017025254A1 (en) * 2015-08-07 2017-02-16 Robert Bosch Gmbh Mof silicon-carbon composite anode material
CN106711456A (en) * 2015-11-12 2017-05-24 中国科学院苏州纳米技术与纳米仿生研究所 Passivated lithium metal-carbon skeleton composite material and preparation method and application thereof
CN105789559A (en) * 2016-04-21 2016-07-20 清华大学 Flexible lithium metal cell negative pole and preparation method thereof
CN107305941A (en) * 2016-04-21 2017-10-31 中国科学院苏州纳米技术与纳米仿生研究所 Lithium carbon composite, its preparation method and application and lithium compensation method
CN108539185A (en) * 2018-05-24 2018-09-14 中南大学 A kind of lithium or anode material of lithium-ion battery and preparation method thereof

Also Published As

Publication number Publication date
CN110931718A (en) 2020-03-27

Similar Documents

Publication Publication Date Title
CN109286020B (en) Negative pole piece and secondary battery
CN110739485A (en) low-temperature lithium ion batteries
CN105453309B (en) Positive electrode comprising graphene for Li-S batteries and preparation method thereof
CN112002883A (en) Silicon-based composite material for negative electrode active material, negative electrode plate and lithium ion battery
CN111490252A (en) Lithium metal protective layer, preparation method thereof and battery with same
CN111600020B (en) Lithium ion battery and preparation method thereof
KR20140070227A (en) Negative active material for rechargeable lithium battery, method of preparing the same, and negative electrode and rechargeable lithium battery including the same
CN110931718B (en) Lithium paste and preparation method and application thereof
CN111244455A (en) Silicon-carbon composite negative electrode material composite conductive agent of lithium ion battery, negative plate and preparation method of negative plate
WO2021008429A1 (en) Secondary battery, and battery module, battery pack and device related thereto
CN110854379B (en) Silicon-carbon composite negative electrode material and preparation method thereof, negative electrode plate and lithium ion battery
CN114552125B (en) Nondestructive lithium supplement composite diaphragm and preparation method and application thereof
CN111653732A (en) Positive electrode material, positive electrode plate and lithium ion battery
CN112635712A (en) Negative plate and lithium ion battery
CN113540423A (en) High-stability silicon-carbon composite negative electrode material, preparation method thereof and lithium ion battery
CN111342049A (en) Modified sodium ion battery positive electrode material, preparation method and battery
CN115911257A (en) Positive electrode plate, electrochemical device and lithium supplementing method
CN111162322A (en) Preparation method of low-temperature lithium ion battery
CN113555541A (en) High-energy-density lithium ion battery
CN113644241A (en) Composite graphite negative electrode material, preparation method thereof and secondary battery
CN111697217A (en) Preparation method of silicon/graphite composite cathode of lithium ion battery
CN112164769A (en) Preparation method of silicon-based negative electrode material based on polyimide-based electrode binder
CN116799210A (en) Composite lithium supplementing material and preparation method thereof, lithium supplementing coating and preparation method thereof, and lithium battery
CN109309228B (en) Positive electrode active material, preparation method, positive electrode and high-specific-energy power battery
CN114105133B (en) Graphite-silicon/silicon oxide-carbon composite material and preparation method and application thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant