CN112151808A - Preparation method of copper foil for lithium battery - Google Patents

Preparation method of copper foil for lithium battery Download PDF

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Publication number
CN112151808A
CN112151808A CN202011105201.XA CN202011105201A CN112151808A CN 112151808 A CN112151808 A CN 112151808A CN 202011105201 A CN202011105201 A CN 202011105201A CN 112151808 A CN112151808 A CN 112151808A
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China
Prior art keywords
copper foil
lithium battery
metal layer
composite metal
preparing
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CN202011105201.XA
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Chinese (zh)
Inventor
易超
王品宇
邵勇
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Heyuan Dongju Energy Technology Co ltd
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Heyuan Dongju Energy Technology Co ltd
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Priority to CN202011105201.XA priority Critical patent/CN112151808A/en
Publication of CN112151808A publication Critical patent/CN112151808A/en
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/64Carriers or collectors
    • H01M4/66Selection of materials
    • H01M4/661Metal or alloys, e.g. alloy coatings
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00Electroplating: Baths therefor
    • C25D3/02Electroplating: Baths therefor from solutions
    • C25D3/56Electroplating: Baths therefor from solutions of alloys
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00Electroplating: Baths therefor
    • C25D3/02Electroplating: Baths therefor from solutions
    • C25D3/56Electroplating: Baths therefor from solutions of alloys
    • C25D3/562Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of iron or nickel or cobalt
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00Electroplating: Baths therefor
    • C25D3/02Electroplating: Baths therefor from solutions
    • C25D3/56Electroplating: Baths therefor from solutions of alloys
    • C25D3/565Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of zinc
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/003Electroplating using gases, e.g. pressure influence
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/34Pretreatment of metallic surfaces to be electroplated
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/48After-treatment of electroplated surfaces
    • C25D5/50After-treatment of electroplated surfaces by heat-treatment
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25DPROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00Electroplating characterised by the article coated
    • C25D7/06Wires; Strips; Foils
    • C25D7/0614Strips or foils
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/64Carriers or collectors
    • H01M4/66Selection of materials
    • H01M4/665Composites
    • H01M4/667Composites in the form of layers, e.g. coatings
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/64Carriers or collectors
    • H01M4/70Carriers or collectors characterised by shape or form
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Manufacturing & Machinery (AREA)
  • Cell Electrode Carriers And Collectors (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention discloses a preparation method of copper foil for a lithium battery, which comprises the following steps: preparing a copper foil, and polishing, cleaning and drying the surface of the copper foil to be used as a copper substrate for later use; under the protection of inert gas, generating a composite metal layer on the surface of the copper foil, wherein the composite metal layer consists of chromium, zinc, nickel and cobalt, and the thickness of the composite metal layer is 1-50 nm, so as to form an alloyed copper foil; and placing the alloyed copper foil into a vacuum cavity, heating to the temperature of 500-700 ℃ under the protection of inert gas, preserving the heat for 3-5 hours, and then cooling to the room temperature to obtain the finished product of the copper foil for the lithium battery. The invention is applied to the lithium battery, has stronger heat resistance and tensile strength, and is not easy to wrinkle and crack.

Description

Preparation method of copper foil for lithium battery
Technical Field
The invention relates to the technical field of lithium batteries, in particular to a preparation method of a copper foil for a lithium battery.
Background
Copper has excellent processing ductility and conductivity, and is widely applied to the conductivity related fields of electric wires, batteries and the like. In the field of power batteries and other lithium ion batteries, copper is also used as a negative current collector, but because the inclination of an electric vehicle with long mileage and the requirement of people on the energy density of the battery are continuously improved due to the current policy, the weight reduction of various material components of the battery becomes an important development direction of the power battery, and copper foil is used as the negative current collector and is also inevitably added into a weight reduction line. In order to solve the problem of high load pressure of pure copper of a negative current collector, researchers make diligent efforts, the thickness of copper foil used by the current negative current collector of the lithium battery is reduced to 7-15 mu m, and the copper has good extensibility and mechanical processing performance, but the processing of the copper to 7-15 mu m is really difficult, and meanwhile, a series of adverse reactions, particularly the processing performance, are brought. As the mechanical properties such as tensile strength, elongation and the like of the metal material are obviously reduced along with the reduction of the size, and the processing difficulty of the micron-sized copper foil is self-evident, the problems of drawing fracture, wrinkle, cracking and the like of the copper foil inevitably occur in the coating process of the lithium battery.
Disclosure of Invention
The invention aims to provide a preparation method of copper foil for a lithium battery.
In order to solve the technical problems, the invention adopts the following technical scheme:
a preparation method of copper foil for a lithium battery comprises the following steps:
preparing a copper foil, and polishing, cleaning and drying the surface of the copper foil to be used as a copper substrate for later use;
under the protection of inert gas, generating a composite metal layer on the surface of the copper foil, wherein the composite metal layer consists of chromium, zinc, nickel and cobalt, and the thickness of the composite metal layer is 1-50 nm, so as to form an alloyed copper foil;
and placing the alloyed copper foil into a vacuum cavity, heating to the temperature of 500-700 ℃ under the protection of inert gas, preserving the heat for 3-5 hours, and then cooling to the room temperature to obtain the finished product of the copper foil for the lithium battery.
The copper foil is immersed in an electroplating solution containing zinc ions with a concentration of 0.25-30 g/L, nickel ions with a concentration of 25-40 g/L, cobalt ions with a concentration of 0.5-2.5 g/L and nickel ions with a concentration of 2.1-7.1 g/L to carry out electroplating, so as to form the composite metal layer.
And during cooling, cooling to 250-450 ℃ at the speed of 5-10 ℃/min, preserving heat for 1-3 h, and then cooling to room temperature.
The inert gas is one or more of nitrogen, argon and helium.
Polishing by adopting 1000# -2000 # Al2O3And (5) finely polishing the polishing powder for 5-10 min.
The chromium adhesion amount in the composite metal layer is 0.04-0.15 mg/dm2The amount of zinc attached is 0.04 to 0.4mg/dm2The amount of nickel deposited is between 0.06 and 0.3mg/dm2The amount of cobalt adhered is 0.07 to 0.8mg/dm2In the meantime.
The copper foil is cleaned by firstly adopting acetone to wash and remove organic matters, then washing an oxidation layer by acid, and finally washing by using deionized water.
The invention is applied to the lithium battery, has stronger heat resistance and tensile strength, and is not easy to wrinkle and crack.
Detailed Description
The present invention will be described in further detail with reference to specific embodiments in order to further understand the features and technical means of the invention and achieve specific objects and functions.
Example one
A preparation method of copper foil for a lithium battery comprises the following steps:
preparing a copper foil, polishing the surface, cleaning and drying the copper foil to be used as a copper substrate for later use. Polishing with 1000# -2000 # Al2O3And (5) finely polishing the polishing powder for 5-10 min. Cleaning copper foil, washing with acetone to remove organic matter, acid washing the oxide layer, and washing with deionized waterAnd washing is carried out, so that the aim of cleaning is fulfilled.
And under the protection of argon, generating a composite metal layer on the surface of the copper foil, wherein the composite metal layer consists of chromium, zinc, nickel and cobalt, and the thickness of the composite metal layer is 10nm, so as to form the alloyed copper foil.
And (3) placing the alloyed copper foil into a vacuum cavity, heating to 500 ℃ under the protection of inert gas, preserving heat for 3 hours, and then cooling to room temperature to obtain a finished product of the copper foil for the lithium battery.
The copper foil is immersed in a plating solution containing zinc ions with a concentration of 0.25g/L, nickel ions with a concentration of 25g/L, cobalt ions with a concentration of 0.5g/L and nickel ions with a concentration of 2.1g/L to be plated, and a composite metal layer is formed.
And during cooling, the temperature is reduced to 250 ℃ at the speed of 5 ℃/min, the temperature is kept for 3h, and then the temperature is cooled to the room temperature.
Further, the amount of chromium adhered to the clad metal layer was 0.05mg/dm2The amount of zinc adhered was 0.05mg/dm2The amount of nickel deposited was 0.08mg/dm2The amount of cobalt adhered was 0.10mg/dm2
Example two
A preparation method of copper foil for a lithium battery comprises the following steps:
preparing a copper foil, polishing the surface, cleaning and drying the copper foil to be used as a copper substrate for later use. Polishing with 1000# -2000 # Al2O3And (5) finely polishing the polishing powder for 5-10 min. The copper foil is cleaned by firstly adopting acetone to wash and remove organic matters, then washing an oxidation layer by acid, and finally washing by using deionized water, thereby achieving the purpose of cleaning.
Under the protection of nitrogen, a composite metal layer is generated on the surface of the copper foil, the composite metal layer is composed of chromium, zinc, nickel and cobalt, the thickness is 20nm, and the alloyed copper foil is formed.
And (3) placing the alloyed copper foil into a vacuum cavity, heating to 600 ℃ under the protection of inert gas, preserving heat for 4 hours, and then cooling to room temperature to obtain a finished product of the copper foil for the lithium battery.
The copper foil is immersed in a plating solution containing zinc ions with a concentration of 10g/L, nickel ions with a concentration of 35 g/L, cobalt ions with a concentration of 1.5g/L and nickel ions with a concentration of 5.1g/L to be plated, and a composite metal layer is formed.
And during cooling, the temperature is reduced to 300 ℃ at the speed of 10 ℃/min, the temperature is kept for 2h, and then the temperature is cooled to the room temperature.
Further, the amount of chromium adhered to the clad metal layer was 0.10mg/dm2The amount of zinc adhered was 0.30mg/dm2The amount of nickel adhered was 0.20mg/dm2The amount of cobalt adhered was 0.50mg/dm2In the meantime.
EXAMPLE III
A preparation method of copper foil for a lithium battery comprises the following steps:
preparing a copper foil, polishing the surface, cleaning and drying the copper foil to be used as a copper substrate for later use. Polishing with 1000# -2000 # Al2O3And (5) finely polishing the polishing powder for 5-10 min. The copper foil is cleaned by firstly adopting acetone to wash and remove organic matters, then washing an oxidation layer by acid, and finally washing by using deionized water, thereby achieving the purpose of cleaning.
Under the protection of nitrogen, a composite metal layer is generated on the surface of the copper foil, the composite metal layer is composed of chromium, zinc, nickel and cobalt, the thickness is 20nm, and the alloyed copper foil is formed.
And (3) placing the alloyed copper foil into a vacuum cavity, heating to 600 ℃ under the protection of inert gas, preserving heat for 4 hours, and then cooling to room temperature to obtain a finished product of the copper foil for the lithium battery.
The copper foil is immersed in a plating solution containing zinc ions at a concentration of 30g/L, nickel ions at a concentration of 40g/L, cobalt ions at a concentration of 2.5g/L, and nickel ions at a concentration of 7.1g/L to perform electroplating, thereby forming a composite metal layer.
And during cooling, the temperature is reduced to 450 ℃ at the speed of 10 ℃/min, the temperature is kept for 1h, and then the temperature is cooled to room temperature.
Further, the amount of chromium adhered to the clad metal layer was 0.15mg/dm2The amount of zinc adhered was 0.4mg/dm2The amount of nickel deposited was 0.3mg/dm2The amount of cobalt adhered was 0.8mg/dm2
Although the present invention has been described in detail with reference to the embodiments, it will be apparent to those skilled in the art that modifications, equivalents, improvements, and the like can be made in the technical solutions of the foregoing embodiments or in some of the technical features of the foregoing embodiments, but those modifications, equivalents, improvements, and the like are all within the spirit and principle of the present invention.

Claims (7)

1. A preparation method of copper foil for a lithium battery comprises the following steps:
preparing a copper foil, and polishing, cleaning and drying the surface of the copper foil to be used as a copper substrate for later use;
under the protection of inert gas, generating a composite metal layer on the surface of the copper foil, wherein the composite metal layer consists of chromium, zinc, nickel and cobalt, and the thickness of the composite metal layer is 1-50 nm, so as to form an alloyed copper foil;
and placing the alloyed copper foil into a vacuum cavity, heating to the temperature of 500-700 ℃ under the protection of inert gas, preserving the heat for 3-5 hours, and then cooling to the room temperature to obtain the finished product of the copper foil for the lithium battery.
2. The method for preparing a copper foil for a lithium battery as claimed in claim 1, wherein the copper foil is immersed in an electroplating solution containing zinc ions at a concentration of 0.25 to 30g/L, nickel ions at a concentration of 25 to 40g/L, cobalt ions at a concentration of 0.5 to 2.5g/L, and nickel ions at a concentration of 2.1 to 7.1g/L to form the composite metal layer by electroplating.
3. The preparation method of the copper foil for the lithium battery as claimed in claim 2, wherein the temperature is reduced to 250-450 ℃ at a speed of 5-10 ℃/min and is kept for 1-3 h, and then the copper foil is cooled to room temperature.
4. The method for preparing copper foil for lithium battery as claimed in claim 3, wherein the inert gas is one or more of nitrogen, argon and helium.
5. The method for preparing copper foil for lithium battery as claimed in claim 4, wherein the polishing is performed by using 1000# -2000 # Al2O3And (5) finely polishing the polishing powder for 5-10 min.
6. The method for preparing copper foil for lithium battery as claimed in claim 5, wherein the adhesion amount of chromium in the clad metal layer is 0.04 to 0.15mg/dm2The amount of zinc attached is 0.04 to 0.4mg/dm2The amount of nickel deposited is between 0.06 and 0.3mg/dm2The amount of cobalt adhered is 0.07 to 0.8mg/dm2In the meantime.
7. The method for preparing copper foil for lithium battery as claimed in claim 5, wherein the copper foil is washed by removing organic substances by acetone washing, then washing the oxide layer by acid, and finally washing by deionized water.
CN202011105201.XA 2020-10-15 2020-10-15 Preparation method of copper foil for lithium battery Pending CN112151808A (en)

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Application Number Priority Date Filing Date Title
CN202011105201.XA CN112151808A (en) 2020-10-15 2020-10-15 Preparation method of copper foil for lithium battery

Publications (1)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104704137A (en) * 2012-10-12 2015-06-10 三井金属矿业株式会社 Surface-treated copper foil, method for manufacturing surface-treated copper foil, and negative electrode material for negative electrode current collector and nonaqueous secondary cell
CN104779367A (en) * 2014-01-15 2015-07-15 金居开发铜箔股份有限公司 Heat-resisting lithium battery copper foil and manufacturing method thereof
US9647272B1 (en) * 2016-01-14 2017-05-09 Chang Chun Petrochemical Co., Ltd. Surface-treated copper foil
CN110952065A (en) * 2019-12-23 2020-04-03 祝珍珍 Copper foil for lithium battery and preparation method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104704137A (en) * 2012-10-12 2015-06-10 三井金属矿业株式会社 Surface-treated copper foil, method for manufacturing surface-treated copper foil, and negative electrode material for negative electrode current collector and nonaqueous secondary cell
CN104779367A (en) * 2014-01-15 2015-07-15 金居开发铜箔股份有限公司 Heat-resisting lithium battery copper foil and manufacturing method thereof
US9647272B1 (en) * 2016-01-14 2017-05-09 Chang Chun Petrochemical Co., Ltd. Surface-treated copper foil
CN110952065A (en) * 2019-12-23 2020-04-03 祝珍珍 Copper foil for lithium battery and preparation method thereof

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Application publication date: 20201229