CN109546080B - Positive pole piece, and preparation method and application thereof - Google Patents

Positive pole piece, and preparation method and application thereof Download PDF

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CN109546080B
CN109546080B CN201811446977.0A CN201811446977A CN109546080B CN 109546080 B CN109546080 B CN 109546080B CN 201811446977 A CN201811446977 A CN 201811446977A CN 109546080 B CN109546080 B CN 109546080B
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electrode material
positive electrode
material layer
conductive agent
sheet according
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CN109546080A (en
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张锁江
宋开放
张兰
巫湘坤
陈占
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Institute of Process Engineering of CAS
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Hebei Aipuai Technology Development Co ltd
Institute of Process Engineering of CAS
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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
    • 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
    • H01M4/04—Processes of manufacture in general
    • H01M4/0402—Methods of deposition of the material
    • H01M4/0404—Methods of deposition of the material by coating on electrode collectors
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • 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
    • H01M4/624—Electric conductive 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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  • Chemical Kinetics & Catalysis (AREA)
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Abstract

The invention relates to a positive pole piece, which comprises a current collector, and a first electrode material layer and a second electrode material layer which are sequentially arranged on one side of the current collector; the conductive agent in the first electrode material layer is a first conductive agent, the conductive agent in the second electrode material layer is a second conductive agent, and the conductivity of the first conductive agent is greater than that of the second conductive agent. According to the invention, different types of conductive agents are arranged in the double-layer electrode material layer of the positive pole piece, so that a good conductive system is constructed, the conductive performance of the positive pole piece is effectively improved, the rapid transfer of charges is promoted, and the electrochemical performance of the battery is improved.

Description

Positive pole piece, and preparation method and application thereof
Technical Field
The invention belongs to the field of batteries, and particularly relates to a positive pole piece, and a preparation method and application thereof.
Background
Lithium ion batteries have the advantages of high specific energy, high operating voltage, and long cycle life, and have been rapidly developed since commercialization. With the wide application of the lithium ion battery in the fields of hybrid electric vehicles and new energy vehicles, higher requirements are put forward on the energy density of the lithium ion battery. Under the same conditions, the high energy density can effectively increase the driving range of the vehicle, so that the energy density of the battery is improved, and the research and development of a power type lithium ion battery is important at present.
Starting from the process aspect, various large battery manufacturers increase the coating thickness of the battery and the proportion of the active material to improve the energy density, but the effect is poor. On one hand, the rate performance of the battery is greatly influenced along with the increase of the thickness of the battery, and under the condition of high rate, the capacity is quickly attenuated, and the cycle performance is poor. On the other hand, the increase of the proportion of the active substances reduces the content of the conductive agent, so that the internal resistance of the battery is increased, the transmission of electrons is influenced, and the electrochemical performance of the battery is further influenced.
CN107742709A discloses a lithium iron phosphate battery positive active material, and preparation and application thereof, wherein the active material comprises two layers, a first layer of active material and a second layer of active material coated on the surface of the first layer of active material; the first layer of active material consists of 80-95 parts by weight of lithium iron phosphate positive electrode material, 3-12 parts by weight of conductive agent and 3-10 parts by weight of first binder; the second layer of active material is composed of, by weight, 85-98 parts of a lithium iron phosphate positive electrode material, 1-8 parts of a conductive agent and 5-8 parts of a second binder. The double-layer lithium iron phosphate positive electrode material prepared by the method has good multiplying power performance, but excessive conductive agent and binder are added, so that the content of positive active substances is low, and the energy density of a lithium ion battery is low.
CN105514349B discloses a lithium ion battery positive plate and a preparation method thereof, wherein the lithium ion battery positive plate comprises a current collector, a conductive coating and an electrode layer; the conductive coating comprises a first layer close to the side of the positive electrode current collector and a second layer close to one side of the electrode layer; the first layer is formed of a first conductive paint containing a binder, a conductive agent, and water, and the second layer is formed of a second conductive paint containing a binder, a swelling agent, a crosslinking agent, a conductive agent, and water; the adhesive is polyolefin resin containing amide groups. The lithium ion battery positive plate prepared by the method has low content of positive active substances, and the energy density of the lithium ion battery is low.
CN106207092A discloses a conductive agent combined type lithium ion battery positive electrode plate, which comprises a current collector and a positive electrode coating film adhered on the current collector, wherein the components of the positive electrode coating film comprise a positive electrode active material, a conductive agent and a binder; the conductive agent is a CB and CNTs combination, a CB and GNPs combination, a CNTs and GNPs combination or a CB, CNTs and GNPs combination. The preparation process comprises the following steps: (1) adding the binder into the solvent, and uniformly stirring and mixing; (2) adding two or three conductive agents of CB, CNTs and GNPs into the solvent, and stirring and mixing uniformly; (3) adding a positive active material, stirring and mixing uniformly to obtain positive slurry; (4) and coating the positive electrode slurry on a current collector, and baking and rolling to obtain the positive electrode plate for the lithium ion battery. The energy density of the positive pole piece prepared by the method is low, and the energy density of the lithium ion battery is low.
Therefore, there is a need in the art to develop a novel positive electrode plate of a lithium ion battery, which has good electrochemical properties, a simple preparation process, and is suitable for industrial production.
Disclosure of Invention
In view of the defects of the prior art, one of the objectives of the present invention is to provide a positive electrode plate, which includes a current collector, and a first electrode material layer and a second electrode material layer sequentially disposed on one side of the current collector;
the conductive agent in the first electrode material layer is a first conductive agent, the conductive agent in the second electrode material layer is a second conductive agent, and the conductivity of the first conductive agent is greater than that of the second conductive agent.
The invention adopts different types of conductive agents in the double-layer electrode material layer of the positive pole piece, thereby obviously improving the contact impedance between the positive pole material and the current collector, constructing a good conductive system, effectively improving the conductive performance of the positive pole piece, promoting the rapid transfer of charges and improving the electrochemical performance of the battery.
Compared with a mode of increasing the content of a conductive agent to improve the conductivity of an electrode material layer, the positive pole piece has higher content of positive active substances and higher energy density, and a lithium ion battery containing the positive pole piece has higher energy density which is not less than 255Wh/kg at the current density of 0.2C.
Preferably, the ratio of the conductivity of the first conductive agent to the conductivity of the second conductive agent is greater than 40, preferably 90 to 120, such as 50, 60, 70, 80, 90, 100, 110, 120, 130, 150, and the like.
According to the invention, the arrangement that the difference between the conductivity of the first conductive agent and the conductivity of the second conductive agent is larger (the ratio is more than 40) is adopted, so that the positive pole piece has good initial coulombic efficiency and excellent cycle stability, the initial coulombic efficiency is more than or equal to 82.6% at the current density of 0.05C, and the cycle capacity retention rate of 50 weeks is more than or equal to 81% at the current density of 0.2C.
The first electrode material layer has higher conductivity, can obviously improve the contact impedance between the positive electrode material and the current collector, can more quickly transmit electrons transmitted from the upper layer to the current collector, and improves the transmission rate of the electrons and lithium ions, so that the positive electrode piece has good electrochemical performance.
The second electrode material layer is in contact with the electrolyte and the first electrode material layer, the contact impedance is low, the transmission rate of electrons and lithium ions is high, and further the conductivity of the conductive agent in the second electrode material layer is not required to be too high; meanwhile, the conductive agent with higher conductivity is mainly one-dimensional and two-dimensional conductive agents, and compared with a zero-dimensional conductive agent, the conductive agent has larger specific surface area, so that more electrolyte is consumed to form an SEI (solid electrolyte interface) film, and the first coulombic efficiency of the positive pole piece is reduced.
Preferably, the content of the first conductive agent and the second conductive agent is each independently selected from 1.5% to 5%, preferably 2% to 3%, such as 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, etc.
Preferably, the content of the first conductive agent in the first electrode material layer is the same as the content of the second conductive agent in the second electrode material layer.
Preferably, the first conductive agent and the second conductive agent include any one of ketjen black, conductive carbon black SP, or CNTs.
Preferably, the content of the cathode material in the first electrode material layer and the content of the cathode material in the second electrode material layer are respectively and independently selected from 90% to 97%, such as 91%, 92%, 93%, 94%, 95%, 96% and the like.
Preferably, the positive electrode materials of the first electrode material layer and the second electrode material layer are the same, and lithium nickel cobalt manganese oxide or lithium nickel cobalt aluminate is preferred.
Preferably, the content of the binder in the first electrode material layer and the second electrode material layer is each independently selected from 1.5% to 5%, such as 1.8%, 2%, 2.2%, 2.5%, 3%, 3.5%, 4%, 4.5%, etc.
Preferably, the binder in the first electrode material layer and the binder in the second electrode material layer are the same, and polyvinylidene fluoride is preferred.
Preferably, the content of the cathode material in the first electrode material layer is the same as the content of the cathode material in the second electrode material layer.
Preferably, the content of the binder in the first electrode material layer is the same as the content of the binder in the second electrode material layer.
According to the invention, the positive electrode material, the binder and the solvent in the first electrode material layer and the second electrode material layer are the same, so that the first electrode material layer and the second electrode material layer have good compatibility, and the cycling stability of the positive electrode piece is high.
Preferably, the current collector is an aluminum foil, preferably an aluminum foil with a thickness of 7-25 μm, such as 8 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 22 μm, and the like.
Preferably, the surface density of the first electrode material layer is 10-20 mg/cm2E.g. 12mg/cm2、14mg/cm2、15mg/cm2、16mg/cm2、18mg/cm2、19mg/cm2And the like.
Preferably, the surface density of the second electrode material layer is 20-30 mg/cm2E.g. 22mg/cm2、24mg/cm2、25mg/cm2、26mg/cm2、28mg/cm2、29mg/cm2And the like.
Preferably, the thickness of the first electrode material layer is 40-110 μm, such as 50 μm, 60 μm, 70 μm, 90 μm, 100 μm, etc.
Preferably, the thickness of the second electrode material layer is 110 to 160 μm, such as 115 μm, 120 μm, 135 μm, 145 μm, 155 μm, and the like.
The invention also aims to provide a preparation method of the positive pole piece, which comprises the following steps:
(1) mixing a positive electrode material, a first conductive agent and a binder, and then adding N-methyl pyrrolidone to adjust viscosity to obtain first electrode slurry;
(2) mixing the positive electrode material, the second conductive agent and the binder, and then adding N-methyl pyrrolidone to adjust the viscosity to obtain second electrode slurry;
(3) and sequentially coating first electrode slurry and second electrode slurry on one side of the current collector, and drying to obtain the positive pole piece.
The preparation method is simple and can be used for industrial production.
Preferably, the mass ratio of the positive electrode material, the first conductive agent and the binder in the first electrode paste in the step (1) is 90-98: 1-5, such as 92:4:4, 94:3:3, 95:2.5:2.5, 96:2:2, 97:2:1, and the like.
Preferably, the mass ratio of the positive electrode material, the second conductive agent and the binder in the second electrode paste in the step (2) is 90-98: 1-5, such as 92:4:4, 94:3:3, 95:2.5:2.5, 96:2:2, 97:2:1, and the like.
Preferably, the viscosity of the first electrode paste is 4200 to 4800 mPas, for example 4300 mPas, 4400 mPas, 4500 mPas, 4587 mPas, 4600 mPas, 4700 mPas, and the like.
Preferably, the viscosity of the second electrode paste is 4200 to 4800 mPas, for example 4300 mPas, 4400 mPas, 4500 mPas, 4587 mPas, 4600 mPas, 4700 mPas, and the like.
Preferably, the coating process of step (3) comprises: and coating the first electrode slurry on the surface of one side of the current collector to obtain a first coating layer, drying the first coating layer, coating the second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling and drying to obtain the positive pole piece.
Preferably, the drying temperature is 60-90 ℃, such as 65 ℃, 70 ℃, 80 ℃, 85 ℃ and the like.
Preferably, the drying time is 4-8 h, such as 5h, 5.5h, 6h, 7h and the like.
Preferably, the rolled density is 3.1-3.7 mg/cm3For example 3.2mg/cm3、3.3mg/cm3、3.4mg/cm3、3.5mg/cm3、3.6mg/cm3And the like.
Preferably, the drying temperature is 80-130 ℃, such as 90 ℃, 100 ℃, 110 ℃, 120 ℃ and the like.
Preferably, the drying time is 10-20 h, such as 12h, 14h, 15h, 16h, 18h and the like.
As a preferred technical scheme, the preparation method of the positive pole piece comprises the following steps:
(1) mixing lithium nickel cobalt aluminate, CNTs and PVDF according to the mass ratio of 90-98: 1-5, and adding N-methyl pyrrolidone to adjust the viscosity to be 4200-4800 mPa & s to obtain first electrode slurry;
(2) mixing lithium nickel cobalt aluminate, conductive carbon black SP and PVDF according to the mass ratio of 90-98: 1-5, and adding N-methyl pyrrolidone to adjust the viscosity to be 4200-4800 mPa & s to obtain second electrode slurry;
(3) coating first electrode slurry on a current collector to obtain a first coating layer, drying the first coating layer at 60-90 ℃ for 4-8 h, coating second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling, wherein the rolling density is 3.1-3.7 mg/cm3And drying at 80-130 ℃ for 10-20 h to obtain the positive pole piece.
The third purpose of the invention is to provide the application of the positive pole piece, which is applied to the field of batteries, preferably the positive pole of a lithium ion battery.
The fourth purpose of the invention is to provide a lithium ion battery, which comprises the positive pole piece of the first purpose.
Preferably, the lithium ion positive electrode plate is one of the positive electrode plates.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention adopts the technical scheme that different types of conductive agents are arranged in the double-layer electrode material layer of the positive pole piece, so that the double-layer electrode material layer has different conductivities, the contact impedance between the positive pole material and the current collector can be obviously improved, a good conductive system is constructed, the electrochemical performance of the battery is improved, and compared with the mode of increasing the content of the conductive agents to improve the conductivity of the electrode material layer, the positive pole piece has higher positive active substance content, the lithium ion battery containing the positive pole piece has higher energy density, and the energy density is more than or equal to 255Wh/kg at the current density of 0.2C.
(2) In a further preferred technical scheme, the invention adopts the setting that the difference between the conductivity of the first conductive agent and the conductivity of the second conductive agent is larger (the ratio is more than 40), so that the contact impedance between the positive electrode material and the current collector in the first electrode material layer can be improved, and the transmission rate of electrons and lithium ions is improved; the second electrode material layer adopts a conductive agent with lower conductivity, and because the contact impedance of the second electrode material layer is lower and the specific surface area of the conductive agent with higher conductivity is larger, more electrolyte can be consumed to form an SEI film, and the first coulombic efficiency of the positive pole piece is reduced.
Drawings
FIG. 1 is a schematic diagram of the structure of a sample prepared in example 1 of the present invention.
Detailed Description
For the convenience of understanding the present invention, the following examples are listed, in which the conductive carbon black SP used in the examples of the present invention is produced in ultra-dense mode in Swiss, has a conductivity of 10S/cm, and the CNTs are the science and technology shares of Tiannai, JiangsuConductivity of 10, manufactured by Limited3S/cm, the Keqin black is produced by LION manufacturer of Japanese LION, and the conductivity is 102S/cm. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.
Example 1
The preparation method of the positive pole piece comprises the following steps:
(1) mixing nickel cobalt lithium aluminate, CNTs and PVDF according to a mass ratio of 97:2:1, adding N-methyl pyrrolidone to adjust the viscosity to 4587mPa & s, and obtaining first electrode slurry;
(2) mixing nickel cobalt lithium aluminate, conductive carbon black SP and PVDF according to a mass ratio of 97:2:1, adding N-methyl pyrrolidone to adjust the viscosity to 4587mPa & s, and obtaining second electrode slurry;
(3) coating a first electrode slurry on a 10 mu m aluminum foil to obtain a first coating layer, drying the first coating layer at 80 ℃ for 6h, coating a second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling, wherein the rolling density is 3.5mg/cm3Drying at 120 ℃ for 12h to obtain the first electrode material layer with the surface density of 14mg/cm2The surface density of the second electrode material layer is 28mg/cm2The positive electrode plate of (2).
Example 2
The difference from example 1 is that the conductive carbon black SP in step (2) is replaced with Ketjen black.
Example 3
The difference from the embodiment 1 is that the CNTs in the step (1) are replaced by Ketjen black.
Example 4
The difference from example 1 is that the ratio of lithium nickel cobalt aluminate, CNTs and PVDF in step (1) is 96:3: 1.
Example 5
The difference from example 1 is that the ratio of lithium nickel cobalt aluminate, CNTs and PVDF in step (2) is 96:3: 1.
Example 6
The preparation method of the positive pole piece comprises the following steps:
(1) mixing nickel cobalt lithium aluminate, CNTs and PVDF according to a mass ratio of 97:2:1, adding N-methyl pyrrolidone to adjust the viscosity to be 4200mPa & s, and obtaining first electrode slurry;
(2) mixing the nickel cobalt lithium manganate, the conductive carbon black SP and the PVDF according to the mass ratio of 97:2:1, and adding N-methyl pyrrolidone to adjust the viscosity to be 4200mPa & s to obtain second electrode slurry;
(3) coating a first electrode slurry on a 7 mu m aluminum foil to obtain a first coating layer, drying the first coating layer at 60 ℃ for 8h, coating a second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling, wherein the rolling density is 3.1mg/cm3Drying at 130 ℃ for 10h to obtain the first electrode material layer with the surface density of 10mg/cm2The surface density of the second electrode material layer is 20mg/cm2The positive electrode plate of (2).
Example 7
The preparation method of the positive pole piece comprises the following steps:
(1) mixing the nickel cobalt lithium manganate, the CNTs and the PVDF according to a mass ratio of 97:2:1, and adding N-methyl pyrrolidone to adjust the viscosity to 4800mPa & s to obtain first electrode slurry;
(2) mixing nickel cobalt lithium aluminate, conductive carbon black SP and PVDF according to a mass ratio of 97:2:1, adding N-methyl pyrrolidone to adjust the viscosity to 4800mPa & s, and obtaining second electrode slurry;
(3) coating a first electrode slurry on an aluminum foil with the thickness of 25 mu m to obtain a first coating layer, drying the first coating layer at the temperature of 90 ℃ for 4h, coating a second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling, wherein the rolling density is 3.7mg/cm3Drying at 80 ℃ for 20h to obtain the first electrode material layer with the surface density of 20mg/cm2The surface density of the second electrode material layer is 30mg/cm2The positive electrode plate of (2).
Comparative example 1
The difference from example 1 is that CNTs are replaced with conductive carbon black SP in step (1).
Comparative example 2
The difference from example 1 is that CNTs is replaced with conductive carbon black SP in step (1), and CNTs is replaced with conductive carbon black SP in step (2).
Comparative example 3
The difference from example 1 is that CNTs is replaced with conductive carbon black SP in step (1), and conductive carbon black SP is replaced with Ketjen black in step (2).
Comparative example 4
The difference from example 1 is that CNTs are replaced with Ketjen black in step (1), and CNTs are replaced with conductive carbon black SP in step (2).
Comparative example 5
The difference from example 1 is that CNTs is replaced with Ketjen black in step (1), and conductive carbon black SP is replaced with Ketjen black in step (2).
Comparative example 6
The difference from the example 1 is that the conductive carbon black SP in the step (2) is replaced by CNTs.
Comparative example 7
The preparation method of the positive pole piece comprises the following steps:
(1) dissolving PVDF in NMP solution according to the mass ratio of nickel cobalt lithium aluminate to conductive carbon black SP to PVDF being 82.5:7.5:10, enabling the total weight ratio of NMP to solid to be 3:1 to prepare slurry with the viscosity of 12000Pa.S, fully stirring the mixed solution for 24 hours, coating the mixed slurry on an aluminum foil with the coating thickness of 15 mu m, and moving the aluminum foil into an oven for drying to obtain a first active material coating;
(2) according to the mass ratio of nickel cobalt lithium aluminate to conductive carbon black SP to PVDF being 87.5:2.5:10, the ratio of NMP to solid content is 4:1, coating slurry with the viscosity of 8000Pa.S is prepared, when a first coating is dried to contain a small amount of NMP and the slurry can not flow automatically, a second layer of slurry is coated on the surface of the first layer of slurry, the coating thickness is 15 mu m, and the double-coating nickel cobalt lithium aluminate anode piece is obtained by drying and rolling.
And (3) performance testing:
the prepared positive pole piece is subjected to the following performance tests:
(1) preparing a lithium ion battery: the prepared positive pole piece is used as a positive pole, and the diaphragm is microporous polypropyleneA diaphragm and an electrolyte of 1.2mol/L LiPF6The preparation process of the negative pole piece comprises the following steps: mixing graphite, sodium carboxymethylcellulose (CMC), Styrene Butadiene Rubber (SBR) and conductive carbon black (SP) for 6-8 h according to the mass fraction of 90%, 2%, 3% and 5%, measuring the viscosity to be 4587mPa & s, coating the mixture on copper foil, finally drying, rolling, die-cutting and drying to obtain a negative pole piece, and mounting the positive pole piece, the negative pole piece electrolyte and a diaphragm to obtain the lithium ion battery.
(2) And (3) energy density testing: the electrochemical performance of the battery is tested by adopting a blue-electricity Xinwei 5V/3A type battery tester, the charge cut-off voltage is 4.2V, the discharge cut-off voltage is 2.75V, the energy of the battery under the current density of 0.2C is tested, and the energy density is equal to the energy/mass of the battery.
(3) The first coulombic efficiency test: the electrochemical performance of the battery is tested by adopting a blue-electricity novacal 5V/3A type battery tester, the charge cut-off voltage is 4.2V, the discharge cut-off voltage is 2.75V, the first charge and discharge efficiency of the battery under the current density of 0.05C is tested, and the first coulombic efficiency is the first discharge specific capacity/the first charge specific capacity.
(4) 50-week cycle capacity retention test: the electrochemical performance of the battery is tested by adopting a blue-electricity newway 5V/3A type battery tester, the charge cut-off voltage is 4.2V, the discharge cut-off voltage is 2.75V, the first charge-discharge efficiency and 50-cycle capacity retention ratio of the battery under the current density of 0.2C are tested, and the 50-cycle capacity retention ratio is the 50 th discharge specific capacity/the first discharge specific capacity.
TABLE 1
Figure BDA0001885934010000121
Figure BDA0001885934010000131
As can be seen from table 1, in the positive electrode plates in embodiments 1 to 7, the setting that the conductivity of the first conductive agent is greater than that of the second conductive agent is adopted, and the positive electrode plates have good electrochemical performance, and under the current density of 0.2C, the energy density of the positive electrode material is greater than or equal to 255Wh/kg, the first coulombic efficiency is greater than or equal to 82.6%, the 50-cycle capacity retention rate is greater than or equal to 81%, particularly in embodiment 1, the ratio of the conductivity of CNTs to the conductivity of conductive carbon black SP is in the range of 90 to 120, and the electrochemical performance is excellent.
As can be seen from table 1, in example 2, the energy density, the first coulombic efficiency and the 50-cycle capacity retention ratio of the cathode material are lower at the current density of 0.2C than those of example 1, probably because the ratio of the electrical conductivity of CNTs to the electrical conductivity of ketjen black is < 40 by replacing the conductive carbon black SP with ketjen black in example 2, so that the energy density, the first coulombic efficiency and the 50-cycle capacity retention ratio of the cathode material are lower at the current density of 0.2C than those of example 1.
As can be seen from table 1, in example 3, the energy density, the first coulombic efficiency and the 50-cycle capacity retention ratio of the positive electrode material are lower at the current density of 0.2C than those of example 1, probably because the CNTs are replaced by the ketjen black in example 3, and although the conductivity of the ketjen black is greater than that of the conductive carbon black SP, the ratio of the conductivity of the ketjen black to that of the conductive carbon black SP is less than 40, so the energy density, the first coulombic efficiency and the 50-cycle capacity retention ratio of the positive electrode material are lower at the current density of 0.2C than those of example 1.
As can be seen from table 1, the 50-cycle capacity retention ratio is lower at the current density of 0.2C in examples 6 and 7 than that of example 1, and the 50-cycle capacity retention ratio is lower at the current density of 0.2C in examples 6 and 7, because the types of the positive electrode materials are different and the compatibility between the two electrode material layers is poor in examples 6 and 7, compared with example 1.
As can be seen from table 1, in comparative example 1, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower, and probably because in comparative example 1, the first conductive agent and the second conductive agent both adopt conductive carbon black SP, the conductivity of the conductive carbon black SP is lower, and further the contact impedance between the first electrode material layer and the current collector is higher, the transmission rate of electrons and lithium ions is slower, and the energy density actually exerted by the cathode material is lower, so in comparative example 1, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower.
As can be seen from table 1, in comparative example 2, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the positive electrode material are lower, probably because the first conductive agent in comparative example 2 is conductive carbon black SP, the conductivity of the conductive carbon black SP is lower, and further the contact impedance between the first electrode material layer and the current collector is higher, the transmission rate of electrons and lithium ions is slower, the energy density actually exerted by the positive electrode material is lower, and the electrochemical performance is poorer; the second conductive agent is CNTs, the electrical conductivity of the CNTs is larger, but the specific surface area of the CNTs is larger, so that more electrolyte is consumed to form an SEI film, and the first coulombic efficiency of the positive pole piece is further reduced, so that in comparative example 2, compared with example 1, under the current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the positive pole material are lower.
As can be seen from table 1, in comparative example 3, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower, and probably because the first conductive agent in comparative example 3 is conductive carbon black SP, the conductivity of the conductive carbon black SP is smaller, the contact impedance between the first electrode material layer and the current collector is larger, the transmission rate of electrons and lithium ions is slower, and the energy density actually exerted by the cathode material is lower, so in comparative example 3, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower than those in example 1.
As can be seen from table 1, in comparative example 4, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency, and the 50-cycle capacity retention rate of the positive electrode material are lower, probably because the first conductive agent in comparative example 4 is ketjen black, the conductivity of the ketjen black is smaller, the contact impedance between the first electrode material layer and the current collector is larger, the transmission rate of electrons and lithium ions is slower, the energy density actually exerted by the positive electrode material is lower, and the electrochemical performance is poorer; the second conductive agent is CNTs, the electrical conductivity of the CNTs is larger, but the specific surface area of the CNTs is larger, so that more electrolyte is consumed to form an SEI film, and the first coulombic efficiency of the positive pole piece is further reduced, so that in comparative example 4, compared with example 1, under the current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the positive pole material are lower.
As can be seen from table 1, in comparative example 5, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower, and probably because in comparative example 5, ketjen black, which has a lower conductivity, is used as the first conductive agent and the second conductive agent, the contact resistance between the first electrode material layer and the current collector is higher, the transmission rate of electrons and lithium ions is slower, and the energy density actually exerted by the cathode material is lower, compared to example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower in comparative example 5.
As can be seen from table 1, in comparative example 6, compared to example 1, the first coulombic efficiency and the 50-cycle capacity retention rate are lower at a current density of 0.2C, and probably because both the first conductive agent and the second conductive agent in comparative example 6 use CNTs, both the double layers are CNTs, the consumption of the electrolyte is too large, an excessive SEI film is formed, and the first coulombic efficiency and the cycle stability of the positive electrode sheet are reduced, so that in comparative example 6, compared to example 1, the first coulombic efficiency and the 50-cycle capacity retention rate are lower at a current density of 0.2C.
As can be seen from Table 1, in comparative example 7, compared with example 1, at a current density of 0.2C, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the cathode material are lower, it is possible that the reason is that the increase of the amount of the conductive carbon black SP in the first electrode material layer is adopted to increase the conductivity of the first electrode material layer in comparative example 7, and thus the active material in which the electrochemical reaction occurs in the first electrode material layer is less, therefore, the energy density of the positive pole piece is lower, meanwhile, the conductivity increased by increasing the quantity of the conductive carbon black SP is smaller, the ratio of the conductivity of the conductive agent in the first electrode material layer to the conductivity of the conductive agent in the second electrode material layer is not in the range of 90-120, therefore, in comparative example 7, the energy density, the first coulombic efficiency and the 50-cycle capacity retention rate of the positive electrode material are lower at the current density of 0.2C compared with example 1.
The applicant states that the present invention is illustrated by the above examples to show the detailed process equipment and process flow of the present invention, but the present invention is not limited to the above detailed process equipment and process flow, i.e. it does not mean that the present invention must rely on the above detailed process equipment and process flow to be implemented. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims (36)

1. The positive pole piece is characterized by comprising a current collector, and a first electrode material layer and a second electrode material layer which are sequentially arranged on one side of the current collector;
the conductive agent in the first electrode material layer is a first conductive agent, the conductive agent in the second electrode material layer is a second conductive agent, the conductivity of the first conductive agent is greater than that of the second conductive agent, the ratio of the conductivity of the first conductive agent to that of the second conductive agent is greater than 40, and the first conductive agent is selected from one-dimensional and two-dimensional conductive agents.
2. The positive electrode sheet according to claim 1, wherein the ratio of the conductivity of the first conductive agent to the conductivity of the second conductive agent is 90 to 120.
3. The positive electrode sheet according to claim 1, wherein the first conductive agent and the second conductive agent are each independently selected from 1.5% to 5%.
4. The positive electrode sheet according to claim 3, wherein the first conductive agent and the second conductive agent are each independently selected from 2% to 3%.
5. The positive electrode sheet according to claim 1, wherein the content of the first conductive agent in the first electrode material layer is the same as the content of the second conductive agent in the second electrode material layer.
6. The positive electrode sheet according to claim 1, wherein the first conductive agent and the second conductive agent comprise any one of ketjen black, conductive carbon black SP, or CNTs.
7. The positive electrode sheet according to claim 1, wherein the content of the positive electrode material in the first electrode material layer and the content of the positive electrode material in the second electrode material layer are each independently selected from 90% to 97%.
8. The positive electrode sheet according to claim 1, wherein the positive electrode material of the first electrode material layer and the positive electrode material of the second electrode material layer are the same.
9. The positive electrode sheet according to claim 8, wherein the positive electrode material of the first electrode material layer and the positive electrode material of the second electrode material layer are lithium nickel cobalt manganese oxide or lithium nickel cobalt aluminate.
10. The positive electrode sheet according to claim 1, wherein the content of the binder in each of the first electrode material layer and the second electrode material layer is independently selected from 1.5% to 5%.
11. The positive electrode sheet according to claim 1, wherein the binder in the first electrode material layer and the second electrode material layer is the same.
12. The positive electrode sheet according to claim 1, wherein the binder in the first electrode material layer and the binder in the second electrode material layer are both polyvinylidene fluoride.
13. The positive electrode sheet according to claim 1, wherein the content of the positive electrode material in the first electrode material layer is the same as the content of the positive electrode material in the second electrode material layer.
14. The positive electrode sheet according to claim 1, wherein the content of the binder in the first electrode material layer is the same as the content of the binder in the second electrode material layer.
15. The positive electrode sheet according to claim 1, wherein the current collector is an aluminum foil.
16. The positive electrode sheet according to claim 15, wherein the current collector is an aluminum foil of 7 to 25 μm.
17. The positive electrode sheet according to claim 1, wherein the first electrode material layer has an areal density of 10 to 20mg/cm2。
18. The positive electrode sheet according to claim 1, wherein the second electrode material layer has an areal density of 20 to 30mg/cm2。
19. The positive electrode sheet according to claim 1, wherein the thickness of the first electrode material layer is 40 to 110 μm.
20. The positive electrode sheet according to claim 1, wherein the thickness of the second electrode material layer is 110 to 160 μm.
21. A method for preparing the positive electrode plate according to any one of claims 1 to 20, wherein the method comprises the following steps:
(1) mixing a positive electrode material, a first conductive agent and a binder, and then adding N-methyl pyrrolidone to adjust viscosity to obtain first electrode slurry;
(2) mixing the positive electrode material, the second conductive agent and the binder, and then adding N-methyl pyrrolidone to adjust the viscosity to obtain second electrode slurry;
(3) and sequentially coating first electrode slurry and second electrode slurry on one side of the current collector, and drying to obtain the positive pole piece.
22. The preparation method according to claim 21, wherein the mass ratio of the positive electrode material, the first conductive agent and the binder in the first electrode paste in the step (1) is 90-98: 1-5.
23. The preparation method according to claim 21, wherein the mass ratio of the positive electrode material, the second conductive agent and the binder in the second electrode paste in the step (2) is 90-98: 1-5.
24. The production method according to claim 21, wherein the viscosity of the first electrode paste is 4200 to 4800 mPa-s.
25. The production method according to claim 21, wherein the viscosity of the second electrode paste is 4200 to 4800 mPa-s.
26. The method of claim 21, wherein the coating of step (3) comprises:
and coating the first electrode slurry on the surface of one side of the current collector to obtain a first coating layer, drying the first coating layer, coating the second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling and drying to obtain the positive pole piece.
27. The method of claim 26, wherein the drying temperature is 60 to 90 ℃.
28. The method of claim 26, wherein the drying time is 4 to 8 hours.
29. The method of claim 26, wherein the rolled density is 3.1 to 3.7mg/cm3。
30. The method of claim 26, wherein the drying temperature is 80-130 ℃.
31. The method of claim 26, wherein the drying time is 10-20 hours.
32. The method of claim 21, comprising the steps of:
(1) mixing lithium nickel cobalt aluminate, CNTs and PVDF according to the mass ratio of 90-98: 1-5, and adding N-methyl pyrrolidone to adjust the viscosity to be 4200-4800 mPa & s to obtain first electrode slurry;
(2) mixing lithium nickel cobalt aluminate, conductive carbon black SP and PVDF according to the mass ratio of 90-98: 1-5, and adding N-methyl pyrrolidone to adjust the viscosity to be 4200-4800 mPa & s to obtain second electrode slurry;
(3) coating first electrode slurry on a current collector to obtain a first coating layer, drying the first coating layer at 60-90 ℃ for 4-8 h, coating second electrode slurry on the dried first coating layer to obtain a second coating layer, and finally rolling, wherein the rolling density is 3.1-3.7 mg/cm3And drying at 80-130 ℃ for 10-20 h to obtain the positive pole piece.
33. Use of the positive electrode sheet according to any one of claims 1 to 20, wherein the positive electrode sheet is used in the field of batteries.
34. Use of the positive electrode sheet according to claim 33, wherein the positive electrode sheet is used for a lithium ion battery positive electrode.
35. A lithium ion battery, characterized in that it comprises a positive electrode sheet according to any one of claims 1 to 20.
36. The lithium ion battery according to claim 35, wherein the lithium ion positive electrode sheet is the positive electrode sheet according to any one of claims 1 to 20.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1383222A (en) * 2001-02-16 2002-12-04 日清纺绩株式会社 Multi-layered electrode structural body, cell using same, dual-layer capacitor and mfg. method for same
CN101635344A (en) * 2008-07-24 2010-01-27 东莞新能源科技有限公司 Anode pole piece of secondary lithium ion battery and preparation method thereof
CN103258999A (en) * 2006-02-01 2013-08-21 加拿大魁北克电力公司 Multi-layer material, production and use thereof as electrode
CN106207088A (en) * 2016-09-30 2016-12-07 上海空间电源研究所 A kind of lithium-sulphur cell positive electrode and preparation method thereof
CN107431186A (en) * 2015-03-17 2017-12-01 株式会社Lg化学 Multi-layered electrode and the lithium secondary battery comprising the multi-layered electrode

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SG71014A1 (en) * 1996-02-07 2000-03-21 Sanyo Electric Co Conductive agent and non-sintered nickel electrode for alkaline storage batteries

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1383222A (en) * 2001-02-16 2002-12-04 日清纺绩株式会社 Multi-layered electrode structural body, cell using same, dual-layer capacitor and mfg. method for same
CN103258999A (en) * 2006-02-01 2013-08-21 加拿大魁北克电力公司 Multi-layer material, production and use thereof as electrode
CN101635344A (en) * 2008-07-24 2010-01-27 东莞新能源科技有限公司 Anode pole piece of secondary lithium ion battery and preparation method thereof
CN107431186A (en) * 2015-03-17 2017-12-01 株式会社Lg化学 Multi-layered electrode and the lithium secondary battery comprising the multi-layered electrode
CN106207088A (en) * 2016-09-30 2016-12-07 上海空间电源研究所 A kind of lithium-sulphur cell positive electrode and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Improvement of lithium-ion battery performance using a two-layered cathode by simultaneous slot-die coating;Li-Chun Chen， Darjen Liu等;《Journal of Energy Storage》;20160108;第157页第2.2节阴极浆料的制备及涂覆，表1，图2 *

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