CN112421050A - High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof - Google Patents

High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof Download PDF

Info

Publication number
CN112421050A
CN112421050A CN202011154802.XA CN202011154802A CN112421050A CN 112421050 A CN112421050 A CN 112421050A CN 202011154802 A CN202011154802 A CN 202011154802A CN 112421050 A CN112421050 A CN 112421050A
Authority
CN
China
Prior art keywords
copper foil
roughness
lithium ion
current collector
ion battery
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.)
Pending
Application number
CN202011154802.XA
Other languages
Chinese (zh)
Inventor
凌敏
孟祥娟
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.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
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 Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN202011154802.XA priority Critical patent/CN112421050A/en
Publication of CN112421050A publication Critical patent/CN112421050A/en
Pending legal-status Critical Current

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
    • H01M4/64—Carriers or collectors
    • H01M4/66—Selection of materials
    • H01M4/661—Metal or alloys, e.g. alloy coatings
    • 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
    • H01M4/64—Carriers or collectors
    • H01M4/70—Carriers or collectors characterised by shape or form
    • 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 high-roughness copper foil for a lithium ion battery negative current collector and a preparation method thereof. The preparation method comprises the following steps: (1) degreasing and pickling the copper foil, and then removing residual acid liquor by using deionized water; (2) treating the copper foil by using the mixed treatment liquid, and removing the redundant mixed treatment liquid after the treatment is finished; (3) and (3) drying the treated copper foil at high temperature and calcining and reducing the treated copper foil by using hydrogen/argon mixed gas to obtain the high-roughness copper foil. The mixed treatment liquid is a mixed liquid of sodium hydroxide and ammonium persulfate, the concentration of the ammonium persulfate is kept unchanged, and the surface appearance of the copper foil, namely the roughness of the copper foil, can be changed by adjusting the concentration of the sodium hydroxide solution, so that the surface roughness of the copper foil is regulated and controlled. The high-roughness copper foil can solve the problem that a silicon material is easy to fall off from a current collector copper foil when the silicon material is taken as a negative active material in the prior art, achieves the effect of increasing the mechanical engagement acting force of a current collector layer and an active material layer, and improves the cycle performance of a lithium ion battery.

Description

High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof
Technical Field
The invention belongs to the technical field of lithium ion negative current collectors, and particularly relates to a high-roughness copper foil for a negative current collector of a lithium ion battery and a preparation method thereof.
Background
Currently, lithium ion batteries are widely applied to various energy storage devices due to the advantages of low cost, long cycle life and high safety. The negative electrode material of lithium ion batteries commercialized at present is mainly graphite. However, since the specific capacity of graphite is limited and the volume specific capacity lifting space is small, the lithium ion battery using graphite as the anode active material cannot meet the use requirements of future high-capacity and small-volume electronic equipment. The silicon has the theoretical gram capacity as high as 4200mAh/g and the theoretical volume specific capacity as high as 7200mAh/cm3Are considered to be the most promising anode materials for next-generation lithium ion batteries. However, the silicon-based material has a large volume change in the lithium removal/insertion process, and is very easy to crush and fall off from the current collector, so that the cycle performance of the lithium ion battery is deteriorated, and further the commercial application of the lithium ion battery is limited.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to provide a preparation method of a high-roughness copper foil for a lithium ion battery negative electrode current collector. Meanwhile, the surface appearance of the copper foil prepared by the invention comprises a needle shape, a rod shape and a petal shape, which is beneficial to increasing the roughness of the surface of the copper foil, enhancing the mechanical occlusion acting force between the current collector and the active material and improving the cycle performance of the lithium ion battery.
The invention aims to provide a preparation method of a high-roughness copper foil for a lithium ion battery cathode current collector.
The invention also aims to provide a high-roughness copper foil for a lithium ion battery negative electrode current collector.
The invention also aims to provide a lithium ion battery negative electrode current collector.
The fourth purpose of the invention is to provide a high-roughness copper foil for a lithium ion battery negative electrode current collector and application of the lithium ion battery negative electrode current collector.
A preparation method of a high-roughness copper foil for a lithium ion battery cathode current collector comprises the following steps:
(1) the copper foil is degreased by acetone solution, then is pickled by sulfuric acid solution with mass fraction of 0.5%, and then is washed by deionized water to remove residual acid liquor for later use.
(2) Treating the copper foil obtained in the step (1) by using mixed treatment liquid, and cleaning redundant mixed treatment liquid after the treatment is finished;
the mixed treatment liquid is a solution composed of ammonium persulfate and sodium hydroxide, wherein the concentration of the ammonium persulfate is 0.05-0.5mol/L, and the concentration of the sodium hydroxide is 2.5-4.5 mol/L.
(3) And (3) drying the treated copper foil at high temperature, and then reducing by using a hydrogen/argon mixed gas to obtain the high-roughness copper foil. Forming needle-shaped, rod-shaped and/or petal-shaped copper hydroxide or copper oxide on the surface of the copper foil treated by the mixed treatment solution, and treating in a blast oven at the temperature of 100 ℃ and 300 ℃ for 1-10h to completely convert the copper hydroxide into the copper oxide; and then placing the copper foil in a hydrogen/argon mixed atmosphere, and reducing the copper oxide on the surface of the copper foil into metal copper in a tubular furnace at 250-450 ℃ for 1-6 h.
In the above technical scheme, preferably, the preparation method of the mixed treatment solution comprises the steps of preparing a sodium hydroxide solution, and then adding ammonium persulfate to obtain the uniform and transparent mixed treatment solution. The concentration of ammonium persulfate is kept unchanged, and the surface appearance of the copper foil, namely the roughness of the copper foil, can be changed by adjusting the concentration of a sodium hydroxide solution, so that the surface roughness of the copper foil is regulated and controlled.
In the step (1), the copper foil is a commercially available single-sided light or double-sided light, the thickness of the battery-grade flat copper foil is 12-50 microns, the thickness of the copper foil is preferably 25 microns, and the copper foil is widely applied to batteries, low in cost, wide in source and easy to obtain.
Preferably, in the step (1), the surface degreasing process is as follows: and wiping the surface of the copper foil by using an acetone solution with the mass fraction of 90%, and removing oil stains on the surface of the copper foil.
Preferably, in the step (1), the acid washing process adopts a sulfuric acid solution with a mass fraction of 0.5%.
Preferably, in step (1), the acid washing is carried out for 20-200s, preferably 60 s.
Preferably, in the step (1), deionized water is used for cleaning the surface of the copper foil after acid cleaning, and redundant acid liquor is cleaned.
In the step (2), the mixed treatment liquid is a solution composed of ammonium persulfate and sodium hydroxide, wherein the concentration of the ammonium persulfate is 0.13mol/L, and the concentration of the sodium hydroxide is 2.5-4.5 mol/L. The surface appearance of the copper foil can be changed by adjusting the concentration of the sodium hydroxide, so that the surface roughness of the copper foil can be regulated and controlled. The concentration of the sodium hydroxide is preferably 3.5mol/L, the surface appearance of the copper foil is rod-shaped, and the lithium ion battery prepared by the copper foil with the appearance has the best cycle performance.
Preferably, the concentration of the ammonium persulfate is fixed, and the concentration of the sodium hydroxide is changed from 2.5 to 4.5 mol/L.
Preferably, when the mixed treatment fluid is prepared, a sodium hydroxide solution with the concentration of 2.5-4.5 mol/L is prepared, and then ammonium persulfate with fixed concentration is added, so that the uniform and transparent mixed treatment fluid is obtained.
The mixed treatment liquid can cause copper oxide or copper hydroxide with different appearances to grow on the surface of the copper foil, and the copper oxide or the copper hydroxide mainly comprises a needle shape, a rod shape and a petal shape. The features increase the surface roughness of the copper foil, thereby increasing the mechanical engagement force between the copper foil and the active material silicon layer, and enhancing the cycle performance of the lithium ion battery.
In the step (2), the treatment process of the mixed treatment solution is carried out at 25-45 ℃, preferably at 25 ℃ and room temperature, so that the mixed treatment solution can be prevented from excessively corroding the surface of the copper foil.
In the step (2), the treatment process of the mixed treatment solution specifically comprises the following steps: and (3) packaging one surface of the copper foil by using a plastic package bag, and then soaking the packaged copper foil in the mixed treatment liquid for treatment, wherein the treatment time is 10-30min, and preferably 20 min.
In the step (2), the treated copper foil is repeatedly washed by absolute ethyl alcohol and deionized water, and the residual mixed treatment solution on the surface of the copper foil is cleaned.
In the step (3), the temperature of the treated copper foil for completely converting the copper hydroxide into the copper oxide in the forced air oven is 180 ℃, and the treatment time is 4 hours.
And (3) reducing the copper foil treated in the blast oven in a tubular furnace by using hydrogen/argon mixed gas, wherein the mass fraction of hydrogen is 5%.
Preferably, in the step (3), the temperature of the treatment in the tube furnace is 250-450 ℃, preferably 250 ℃ and the treatment time is 6 h.
The invention further provides a high-roughness copper foil for the lithium ion battery negative current collector, which is prepared by the method, and the surface appearance of the high-roughness copper foil mainly comprises a nanometer needle-shaped structure, a rod-shaped structure and a petal-shaped structure.
The invention further provides a lithium ion battery negative electrode current collector which comprises the high-roughness copper foil prepared by the method.
Finally, the invention also provides the high-roughness copper foil for the lithium ion battery negative current collector and the application of the lithium ion battery negative current collector in an energy storage device.
Compared with the prior art, the invention has the beneficial effects that:
(1) the invention adopts a treatment method of chemical liquid soaking, the preparation process flow is simple, the production period is short, the mixed treatment liquid is simple and easy to prepare, and the commercial production of the high-roughness copper foil preparation is very favorably realized.
(2) The preparation raw materials of the mixed treatment solution and the copper foil adopted in the invention are common commercial raw materials, and have wide sources and low cost.
(3) The mixed treatment liquid adopted by the invention is simple to prepare, only comprises two types of sodium hydroxide and ammonium persulfate, is simple in preparation process, and is easy to realize commercial production.
(4) The surface appearance of the copper foil prepared by the method comprises a needle shape, a rod shape and a petal shape, which is beneficial to increasing the roughness of the surface of the copper foil, enhancing the mechanical occlusion acting force between the current collector and the active material and improving the cycle performance of the lithium ion battery.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
Fig. 1 is a scanning electron micrograph of the surface of the high-roughness copper foil prepared in example 1.
Fig. 2 is a scanning electron micrograph of the surface of the high-roughness copper foil prepared in example 2.
Fig. 3 is a scanning electron micrograph of the surface of the high roughness copper foil prepared in example 3.
Fig. 4 is a scanning electron micrograph of the surface of the high roughness copper foil prepared in example 4.
Fig. 5 is a scanning electron micrograph of the surface of the high roughness copper foil prepared in example 5.
FIG. 6 is a SEM photograph of the surface of the high-roughness copper foil prepared in example 6
Fig. 7 is a scanning electron micrograph of the surface of the high roughness copper foil prepared in example 7.
Fig. 8 is a scanning electron micrograph of the surface of the commercial base foil of comparative example 1.
Detailed Description
As described in the background, conventional copper foils for negative current collectors of lithium ion batteries do not satisfy the practical requirements of silicon as an active material. The silicon active material has high energy density, but the silicon active material layer is easy to fall off from the negative current collector during the charge and discharge processes. Therefore, the present invention provides a method for preparing a high roughness copper foil for a lithium ion battery cathode current collector, and the present invention is further described with reference to the accompanying drawings and the detailed description.
The copper foil adopted in the embodiment of the invention is a single-light copper foil purchased from the industry of self-bright copper.
Example 1
S1) preparation of high-roughness copper foil A1
(1) After removing oil from the acetone solution of the copper foil of the battery-grade current collector with the single-sided light thickness of 25 micrometers, washing the copper foil with deionized water and absolute ethyl alcohol. And (3) pickling the cleaned copper foil with a sulfuric acid solution with the mass fraction of 0.5% for 60s to remove the copper oxide layer in front of the copper foil, repeatedly washing the pickled copper foil with deionized water, and drying to ensure that the residual acid solution on the surface of the copper foil is removed.
(2) And (2) packaging the smooth surfaces on the two surfaces of the copper foil in the step (1) by using a plastic packaging bag, and then soaking the copper foil in a mixed treatment solution containing 0.13mol/L ammonium persulfate and 2.5mol/L sodium hydroxide. The soaking time is 20min, and the temperature is 25 ℃ at room temperature.
(3) And (3) repeatedly washing the copper foil in the step (2) by using deionized water and absolute ethyl alcohol to wash away residual mixed treatment liquid on the surface of the copper foil, and then drying for 4 hours in a blowing oven at 180 ℃.
(4) And (4) calcining the copper foil dried in the step (3) in a tubular furnace in the atmosphere of hydrogen/argon mixed gas at the calcining temperature of 250 ℃ for 6 hours to obtain the high-roughness copper foil.
The high-roughness copper foil prepared in the example was observed under a scanning electron microscope, and the observation result is shown in fig. 1; as can be seen from fig. 1: the surface of the copper foil prepared in the embodiment contains a nano needle-shaped structure, and the roughness of the nano needle-shaped structure is higher than that of bare copper.
S2) manufacturing a pole piece N1:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A1, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N1.
S3) preparation of lithium ion half cell C1:
(1) the diaphragm is a 25 mu m polypropylene film;
(2) the electrolyte consists of a non-aqueous organic solvent and LiPF6Composition of, wherein, LiPF6In the electricityThe molar concentration of the hydrolysate is 1M, and the volume ratio of the non-aqueous organic solvent is 1: 1, and simultaneously contains 10% of fluoroethylene carbonate by volume;
(3) and transferring the prepared negative pole piece into an inert atmosphere glove box, stacking the pole piece N1, a diaphragm and a lithium piece in sequence, and filling electrolyte for assembly to finish the assembly of the lithium ion half battery, wherein the obtained lithium ion secondary battery is recorded as C1.
Example 2
S1) preparation of high-roughness copper foil A2
(1) The difference from example 1 is that the concentration of sodium hydroxide in the mixed treatment solution in step (2) was 3.5mol/L, and a copper foil with high roughness was described as A2.
(2) The high-roughness copper foil prepared in the example was observed under a scanning electron microscope, and the observation result is shown in fig. 2; as can be seen from fig. 2: the surface of the copper foil prepared in this example contains a nanorod structure with higher roughness than bare copper.
S2) manufacturing a pole piece N2:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A2, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N2.
S3) preparation of lithium ion half cell C2:
(1) the fabrication process was the same as for the lithium-ion half cell C1, except that the pole piece N1 was changed to N2, and the resulting lithium-ion half cell was designated C2.
Example 3
S1) preparation of high-roughness copper foil A3
(1) The difference from example 1 is that the concentration of sodium hydroxide in the mixed treatment solution in step (2) was 4.5mol/L, and a copper foil having high roughness was identified as A3.
(2) The high-roughness copper foil prepared in the example was observed under a scanning electron microscope, and the observation result is shown in fig. 3; as can be seen in fig. 3: the surface of the copper foil prepared in the embodiment contains a nano petal-shaped structure, and the roughness of the copper foil is higher than that of bare copper.
S2) manufacturing a pole piece N3:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A3, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N3.
S3) preparation of lithium ion half cell C3:
(1) the fabrication process was the same as for the lithium-ion half cell C1, except that the pole piece N1 was changed to N3, and the resulting lithium-ion half cell was designated C3.
Example 4
S1) preparation of high-roughness copper foil A4
(1) The difference from example 1 is that the treatment temperature of the mixed treatment solution in step (2) was 35 ℃ to obtain a copper foil with high roughness designated as A4.
(2) The high-roughness copper foil prepared in this example was observed under a scanning electron microscope, and the observation results are shown in fig. 4; as can be seen in fig. 4: the surface of the copper foil prepared in this example contained a nanorod structure.
S2) manufacturing a pole piece N4:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A4, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N4.
S3) preparation of lithium ion half cell C4:
(1) the fabrication process was the same as for the lithium-ion half cell C1, except that the pole piece N1 was changed to N4, and the resulting lithium-ion half cell was designated C4.
Example 5
S1) preparation of high-roughness copper foil A5
(1) The difference from example 1 is that the treatment temperature of the mixed treatment solution in step (2) was 45 ℃ to obtain a highly roughened copper foil designated as A5.
(2) The high-roughness copper foil prepared in this example was observed under a scanning electron microscope, and the observation results are shown in fig. 5; as can be seen from fig. 5: the surface of the copper foil prepared in the embodiment contains a nano petal structure.
S2) manufacturing a pole piece N5:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A5, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N5.
S3) preparation of lithium ion half cell C5:
(1) the fabrication process was the same as for the lithium-ion half cell C1, except that the pole piece N1 was changed to N5, and the resulting lithium-ion half cell was designated C5.
Example 6
S1) preparation of high-roughness copper foil A6
(1) The difference from example 1 is that the calcination temperature in step (4) was 350 ℃, and a highly roughened copper foil was designated as a 6.
(2) The high-roughness copper foil prepared in this example was observed under a scanning electron microscope, and the observation results are shown in fig. 6; as can be seen in fig. 6: the nanoneedle structure on the surface of the copper foil prepared in this example becomes less apparent.
S2) manufacturing a pole piece N6:
(1) mixing polyacrylic acid (PAA), binder Super P and active material nano-silicon in 15 weight portions, mixing uniformly in mortar, and addingAdding 0.2ml of secondary water to obtain cathode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A6, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N6.
S3) preparation of lithium ion half cell C6:
(1) the fabrication process was the same as for the lithium-ion half cell C1, except that the pole piece N1 was changed to N6, and the resulting lithium-ion half cell was designated C6.
Example 7
S1) preparation of high-roughness copper foil A7
(1) The difference from example 1 is that the calcination temperature in step (4) was 500 ℃ to obtain a highly roughened copper foil designated as A7.
(2) The high-roughness copper foil prepared in this example was observed under a scanning electron microscope, and the observation results are shown in fig. 7; as can be seen in fig. 7: the copper foil surface prepared in this example was substantially invisible to the prior nanoneedle structures.
S2) manufacturing a pole piece N7:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil A7, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed and the resulting piece was designated N7.
S3) preparation of lithium ion half cell C7:
(1) the fabrication process was the same as for the lithium-ion half cell C1, except that the pole piece N1 was changed to N7, and the resulting lithium-ion half cell was designated C7.
Comparative example 1
S1) testing of the raw foil D1
(1) The comparative example is directly observed by adopting 25-micron single-sided optical copper foil D1 under a scanning electron microscope, and the observation result is shown in FIG. 8; as can be seen in fig. 8: in the comparative example, the surface appearance of the copper foil is a random copper tumor structure.
S2) manufacturing a pole piece DN 1:
(1) mixing 15 parts by mass of polyacrylic acid (abbreviated as PAA), 15 parts by mass of binder Super P and 70 parts by mass of active material nano-silicon uniformly by using a mortar, and adding 0.2ml of secondary water to obtain negative electrode slurry; uniformly coating the negative electrode slurry on a modified high-roughness copper foil D1, wherein the solid coating weight is 1mg/cm2The pieces were then dried in a vacuum oven at 100 ℃ for 12 hours and weighed, and the resulting piece was identified as DN 1.
S3) preparation of lithium ion half cell DC 1:
(1) the diaphragm is a 25 mu m polypropylene film;
(2) the electrolyte consists of a non-aqueous organic solvent and LiPF6Composition of, wherein, LiPF6The molar concentration in the electrolyte is 1M, and the nonaqueous organic solvent comprises a solvent with a volume ratio of 1: 1, and simultaneously contains 10% of fluoroethylene carbonate by volume;
(3) and transferring the prepared negative pole piece into an inert atmosphere glove box, stacking the pole piece DN1, a diaphragm and a lithium piece in sequence, and filling electrolyte for assembly, namely completing the assembly of the lithium ion half battery, wherein the obtained lithium ion secondary battery is recorded as DC 1.
Performance testing
(1) The method for testing the cycle capacity retention rate of the half-cell in C1-C6 and DC1 respectively comprises the following steps:
(2) and (3) taking each battery, standing and activating for 12 hours, then carrying out constant-current charge and discharge at a rate of 0.2C, and recording discharge capacities of 10 th, 20 th, 30 th, 40 th and 50 th times of circulation respectively.
(3) The capacity retention ratio of the battery at the N-th time was the discharge capacity at the N-th time/the discharge capacity at the first time × 100%.
(4) The test results are shown in table 1.
TABLE 1 Capacity Retention ratio for 50 cycles of different batteries
Figure BDA0002742369520000131
As can be seen from the data in Table 1, the capacity retention rate of the batteries C1-C6 is far higher than that of the battery DC1 after 50 cycles. By combining scanning electron microscope images of A1-A6 and D1, the roughness of the surface of the modified copper foil is obviously enhanced, and the mechanical meshing acting force between the copper foil and the silicon active material layer is increased, so that the cycle performance and the stability of the lithium ion battery are obvious. The copper foil surface which can reflect different morphologies from the side has different roughness, and the roughness affects the acting force between the copper foil and the active material layer, thereby indirectly affecting the cycle performance of the battery. And we further find that the cycle performance of the lithium ion battery is superior to that of a petal-shaped structure and a needle-shaped structure when the copper foil is in a rod-shaped structure.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. 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 (10)

1. A preparation method of a high-roughness copper foil for a lithium ion battery cathode current collector is characterized by comprising the following steps:
(1) firstly, removing oil on the surface of a copper foil by using an acetone solution, then carrying out acid washing by using a sulfuric acid solution with the mass fraction of 0.5%, and washing away residual acid liquor by using deionized water after acid washing for later use;
(2) treating the copper foil obtained in the step (1) by using mixed treatment liquid, and cleaning redundant mixed treatment liquid after the treatment is finished;
the mixed treatment liquid is a mixed solution consisting of ammonium persulfate and sodium hydroxide, wherein the concentration of the ammonium persulfate is 0.05-0.5mol/L, and the concentration of the sodium hydroxide is 2.5-4.5 mol/L;
(3) forming needle-shaped, rod-shaped and/or petal-shaped copper hydroxide or copper oxide on the surface of the copper foil treated by the mixed treatment solution, and treating in a blast oven at the temperature of 100 ℃ and 300 ℃ for 1-10h to completely convert the copper hydroxide into the copper oxide; and then placing the copper foil in a hydrogen/argon mixed atmosphere, and reducing the copper oxide on the surface of the copper foil into metal copper in a tubular furnace at 250-450 ℃ for 1-6 h.
2. The preparation method of the high-roughness copper foil for the lithium ion battery negative electrode current collector according to claim 1, wherein the preparation method of the mixed treatment fluid comprises the steps of preparing a sodium hydroxide solution, and then adding ammonium persulfate to obtain the uniform and transparent mixed treatment fluid.
3. The method for preparing the high-roughness copper foil for the negative electrode current collector of the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (1), the copper foil is a battery-grade flat copper foil with double-sided light or single-sided light and the thickness of 12-50 microns.
4. The method for preparing the high-roughness copper foil for the negative electrode current collector of the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (1), the surface oil removal process is to wipe the surface of the copper foil by using an acetone solution with the mass fraction of 90% to remove oil stains on the surface; the acid washing process adopts a sulfuric acid solution with the mass fraction of 0.5%, and the acid washing time is 20-200 s.
5. The method for preparing the high-roughness copper foil for the negative electrode current collector of the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (2), the copper foil in the step (1) is treated by using the mixed treatment liquid at 25-45 ℃; the method specifically comprises the following steps: and (3) packaging one surface of the copper foil by using a plastic package bag, and then soaking the packaged copper foil in the mixed treatment liquid for treatment, wherein the treatment time is 10-30 min.
6. The method for preparing the high-roughness copper foil for the negative electrode current collector of the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (2), the treated copper foil pair is repeatedly cleaned by deionized water and absolute ethyl alcohol to wash away residual mixed treatment liquid.
7. The method for preparing the high-roughness copper foil for the negative electrode current collector of the lithium ion battery according to claim 1, wherein the method comprises the following steps: in the step (3), the temperature of a blast oven for converting the copper hydroxide into the copper oxide is 180 ℃, and the treatment time is 4 hours;
in a tubular furnace, the mass fraction of hydrogen in the hydrogen/argon mixed gas is 5%, the treatment temperature is 250 ℃, and the treatment time is 6 h.
8. The utility model provides a lithium ion battery negative pole is high roughness copper foil for current collector which characterized in that: the high-roughness copper foil prepared by the method of any one of claims 1 to 7 has a surface with a shape of a nanometer needle, a rod or a petal.
9. A lithium ion battery negative current collector is characterized in that: the current collector comprises a high roughness copper foil prepared according to the method of any one of claims 1 to 7.
10. Use of the lithium ion battery negative electrode current collector of claim 9 in an energy storage device.
CN202011154802.XA 2020-10-26 2020-10-26 High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof Pending CN112421050A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011154802.XA CN112421050A (en) 2020-10-26 2020-10-26 High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011154802.XA CN112421050A (en) 2020-10-26 2020-10-26 High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof

Publications (1)

Publication Number Publication Date
CN112421050A true CN112421050A (en) 2021-02-26

Family

ID=74840395

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011154802.XA Pending CN112421050A (en) 2020-10-26 2020-10-26 High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof

Country Status (1)

Country Link
CN (1) CN112421050A (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008226800A (en) * 2007-03-16 2008-09-25 Fukuda Metal Foil & Powder Co Ltd Copper foil for lithium secondary battery negative electrode collector and its manufacturing method
CN103500836A (en) * 2013-10-17 2014-01-08 山东玉皇化工有限公司 Roughened copper-foil current collector for lithium ion battery and method for manufacturing roughened copper-foil current collector
CN108666579A (en) * 2017-03-28 2018-10-16 通用汽车环球科技运作有限责任公司 The electrode of lithium cell of copper foil current collector is modified using surface
CN109301255A (en) * 2018-10-15 2019-02-01 武汉倍特能科技有限公司 A kind of 3D porous current collector and its preparation method and application
CN111600036A (en) * 2020-06-01 2020-08-28 南开大学 Three-dimensional porous copper oxide modified copper foil for lithium metal battery current collector and preparation method and application thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008226800A (en) * 2007-03-16 2008-09-25 Fukuda Metal Foil & Powder Co Ltd Copper foil for lithium secondary battery negative electrode collector and its manufacturing method
CN103500836A (en) * 2013-10-17 2014-01-08 山东玉皇化工有限公司 Roughened copper-foil current collector for lithium ion battery and method for manufacturing roughened copper-foil current collector
CN108666579A (en) * 2017-03-28 2018-10-16 通用汽车环球科技运作有限责任公司 The electrode of lithium cell of copper foil current collector is modified using surface
CN109301255A (en) * 2018-10-15 2019-02-01 武汉倍特能科技有限公司 A kind of 3D porous current collector and its preparation method and application
CN111600036A (en) * 2020-06-01 2020-08-28 南开大学 Three-dimensional porous copper oxide modified copper foil for lithium metal battery current collector and preparation method and application thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
CHUNZHONG LI等: ""Sculpturing metal foams toward bifunctional 3D copper oxide nanowire arrays for pseudocapacitance and enzyme-free hydrogen peroxide detection"", 《JOURNAL OF MATERIALS CHEMISTRY A》 *

Similar Documents

Publication Publication Date Title
CN111600036A (en) Three-dimensional porous copper oxide modified copper foil for lithium metal battery current collector and preparation method and application thereof
CN105428647B (en) A kind of two cobaltous selenides/carbon nanomaterial and preparation method and application
CN109360939A (en) A kind of flexibility of lithium ion battery is without collector thin film pole piece preparation method
CN108807842B (en) Silicon @ carbon-graphene-based flexible composite material, preparation method thereof and lithium battery
CN110444821B (en) Preparation method of flexible miniature alkaline zinc battery based on three-dimensional electrode
CN109712817B (en) Nano sponge carbon compositeCu2O and Cu flexible electrode material and preparation method thereof
CN105826528B (en) A kind of porous silicon-carbon/carbon-copper composite material and its preparation method and application
CN111807345A (en) Silicon-carbon composite material, preparation method thereof, lithium battery negative electrode material and lithium battery
CN110304658B (en) Nb for lithium ion battery18W16O93Negative electrode material and preparation method thereof
CN109301203B (en) Copper/copper oxide/tin dioxide/carbon cathode of three-dimensional sea urchin/porous composite structure lithium ion battery and preparation method thereof
CN113173600B (en) Preparation method and application of three-dimensional multi-channel hollow walnut-shaped vanadium dioxide @ carbon composite material
CN110482523B (en) Nitrogen-doped hierarchical porous carbon material and application thereof in preparation of supercapacitor
CN112054160A (en) Vanadium pentoxide positive electrode material and preparation method and application thereof
CN105552320B (en) A kind of Ni-based Sn/SnO/SnO of foam2Three-dimensional porous negative electrode material of stratiform and preparation method thereof
CN112421050A (en) High-roughness copper foil for negative current collector of lithium ion battery and preparation method thereof
CN111525097B (en) Negative electrode material, preparation method and application thereof
CN104953114B (en) Cobaltosic oxide-stannic disulfide nano-complex preparation method
CN116190668A (en) Ultralight current collector and preparation method and application thereof
CN115377530A (en) Positive electrode lithium supplement material, preparation method thereof and lithium battery
CN115101731A (en) Negative electrode material, preparation method thereof, negative electrode plate and secondary battery
CN113201808A (en) Porous fiber silicon-oxygen negative electrode composite material and preparation method thereof
CN110600717A (en) Polyacrylonitrile-Li3VO4Lithium ion battery cathode material and preparation method thereof
CN111384365A (en) Preparation method of carbon-coated multilayer NiO hollow sphere composite material
US20220140336A1 (en) Positive electrode active material for lithium-ion secondary cell, and lithium-ion secondary cell
CN111261857B (en) FePS for sodium ion battery3/NC composite negative electrode material, preparation method thereof and sodium ion battery

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
RJ01 Rejection of invention patent application after publication

Application publication date: 20210226

RJ01 Rejection of invention patent application after publication