KR102378297B1 - Electrodeposited copper foil, current collectors for negative electrode of lithium-ion secondary batteries and lithium-ion secondary batteries - Google Patents

Abstract

The electrodeposited copper foil applied as a negative electrode current collector of a lithium ion secondary battery according to the present invention is characterized in that the surface roughness of the mat surface (M surface) of the electrodeposited copper foil has a Rsm of 50 μm or more and 125 μm or less.

Description

Lithium ion secondary battery, the current collector constituting the negative electrode of the secondary battery, and the electrodeposited copper foil constituting the negative electrode current collector

The present invention relates to an electrodeposited copper foil for a negative electrode current collector of a lithium ion secondary battery having excellent adhesion to an anode material, a negative electrode current collector for a lithium ion secondary battery comprising the electrodeposited copper foil, and a lithium ion secondary battery comprising the negative electrode current collector will be.

In the field of electronic devices, as the demand for portable use of devices increases, miniaturization and weight reduction of devices is progressing. For this reason, the development of a battery having a high energy density, in particular a secondary battery, is required. As a candidate for a secondary battery that satisfies this requirement, there is a lithium ion secondary battery. A lithium ion secondary battery has a high voltage and a high energy density, and is also lightweight, compared with a nickel cadmium battery, a lead battery, and a nickel hydride battery. Lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, or a composite oxide thereof is used as a positive electrode active material of a lithium ion secondary battery, and a carbon material such as graphite or amorphous carbon is used as a negative electrode active material. A metal foil is used as a current collector for drawing a current from these positive/negative active materials and inducing it to a battery terminal. In particular, copper foil does not form a compound with lithium, has good electrical conductivity, and has the characteristics of low cost, and is widely used as a negative electrode current collector. The copper foil includes a rolled copper foil manufactured by rolling processing and an electrodeposited copper foil manufactured by electrolytic precipitation. Rolled copper foil has a disadvantage in that the adhesive strength with the active material is weak because it has high strength but has a smooth surface. For this reason, if the charging and discharging cycles are repeated, the active material is peeled off at the bonding interface with the rolled copper foil, which leads to a decrease in the charging and discharging capacity and shortening of the cycle life. In addition, since the surface of the electrodeposited copper foil is somewhat rough, the adhesion with the active material is good, but the strength is weak, and it causes disadvantages such as cracks according to charging and discharging, which causes a decrease in charge/discharge capacity and deterioration of cycle life.

In general, the electrodeposited copper foil is produced by a foil making device as shown in Fig. 1, and a rotating metal negative electrode drum 12 with a mirror-polished surface thereof, and an insoluble copper foil disposed at the lower half of the negative electrode drum and surrounding the negative electrode drum It consists of a metal anode 11 (a titanium electrode coated with zinc or noble metal oxide), a copper electrolyte solution 13 flows between the anode drum 12 and the anode 11, and an electric potential is applied therebetween. Copper is electrodeposited on (12), and the electrodeposited copper is peeled off from the negative electrode drum (12) in a state to a predetermined thickness, thereby continuously manufacturing an electrolytic copper foil (14).

Although the electrolytic copper foil 14 obtained in this way is generally called raw foil (or raw foil), it is used as a copper foil for a negative electrode current collector of a lithium ion secondary battery or a copper foil for a printed wiring board as it is or by surface treatment. .

In the electrodeposited copper foil manufactured through the foil making device of FIG. 1 , the surface exposed to the electrolyte is a rough surface (matte surface) having a constant roughness, and the surface on the opposite side of the drum side is a glossy surface (shiny surface).

A typical characteristic required for an electrodeposited copper foil used as a current collector for the negative electrode is adhesion to the negative electrode active material. As a general method for improving the adhesion with the negative electrode active material layer, a surface treatment for forming irregularities on the surface of the copper foil called roughening treatment is exemplified. As a roughening treatment method, various methods such as blast treatment, rolling with a roughening roll, mechanical polishing, electrolytic polishing, chemical polishing, and plating of electrodeposited particles are known, and among them, plating of electrodeposited particles is the most widely used.

Japanese Patent Publication No. 3733065 (Patent Document 1) aims to improve adhesion by electrodepositing a large number of dendritic or microspherical copper on the surface of copper foil using an acidic copper sulfate plating bath to form fine irregularities, or expansion of an active material with a large volume change. Disclosed is a method for preventing peeling due to concentration of stress at an interface of a current collector by concentrating stress on a concave portion of an active material layer to form a crack. For this purpose, Patent Document 1 proposes that the adhesion between the current collector and the active material is improved by using a copper foil having a large value of the preferable surface roughness Ra of the copper foil as the current collector. That is, the surface roughness Ra of the current collector is preferably 0.01 µm or more, more preferably the surface roughness Ra is 0.01 to 1 µm, and still more preferably 0.05 to 0.5 µm.

Moreover, as a method of improving rust prevention property, the method of subjecting the copper foil surface to a chromate treatment or a silane coupling process is known. The silane coupling process also acquires the adhesive improvement effect. For example, in Japanese Patent Application Laid-Open No. 2008-184657 (Patent Document 2), a metal selected from at least one of nickel, cobalt, tungsten, and molybdenum on at least one surface of copper foil, or phosphorus which is a metalloid metal with these metals, or A method for improving adhesiveness and rust prevention properties by forming a barrier layer formed between boron, performing a chromate treatment using trivalent chromium as a chromium source on the barrier layer, and performing a silane coupling treatment on the trivalent chromate film is described.

On the other hand, techniques for reducing the surface roughness of both surfaces (rough surface and glossy surface) of an electrodeposited copper foil or reducing the difference in the surface roughness of both surfaces have also been proposed (Patent Document 3, Patent Document 4, and Patent Document 5). The roughness of the rough surface of the electrodeposited copper foil proposed by these patent documents has achieved Ra 0.1 μm or less and Rz 2.0 μm or less.

JP 3733067 B JP 2008-184657 A WO 2004-055246 A WO 2004-059040 A US 2014-0023955 A

As described above, in the prior art, in order to improve the adhesion between the electrodeposited copper foil as the anode current collector and the slurry as the anode active material, it has been focused on controlling the surface roughness (Rz, Ra) of the glossy surface and the matte surface.

However, the present inventors found that the centerline average roughness (Ra) and 10-point average roughness (Rz), which are surface roughness parameters of the existing electrodeposited copper foil, are all measured by the amplitude of the peak and valley of the surface irregularities. As a method, we did not pay attention to the width of the unevenness. However, it was found that the adhesion between the electrodeposited copper foil as the anode current collector and the slurry as the anode active material greatly depends on the amplitude characteristics of the concavities and convexities as well as the width characteristics of the concavities and convexities.

Accordingly, an object of the present invention is to optimize the degree of Rsm, which is a surface roughness parameter for enhancing adhesion between an electrodeposited copper foil used as a negative electrode current collector of a high-capacity secondary battery and a negative electrode active material slurry. In particular, the present invention pays attention to the average width characteristics of the surface asperities formed on the matte surface and the shiny surface of the copper foil produced by electrolysis, and it has been found that this average width characteristic has a great influence on the adhesion of the negative electrode active material. Therefore, by optimizing the factor (Rsm) representing the mean spacing parameter of the surface of the electrodeposited copper foil, particularly the unevenness of the mat surface, it is intended to enhance the adhesion between the electrodeposited copper foil used as the negative electrode current collector and the negative electrode active material slurry.

The technical problem to be achieved by the present invention is not limited to the above-mentioned problems, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the description of the invention described below.

In an electrodeposited copper foil applied as a negative electrode current collector of a lithium secondary battery according to an aspect of the present invention for achieving the above-described technical problem, the surface roughness of the mat surface (M surface) of the electrodeposited copper foil is 50 μm or more and 125 μm or less in Rsm. characterized by having

A chromate protective layer is formed on the matte or glossy surface of the electrodeposited copper foil, the tensile strength of the electrodeposited copper foil is preferably 25 to 70 kgf/mm 2 , and the thickness thereof is preferably 3 to 20 μm.

According to another aspect of the present invention, a method for manufacturing an electrodeposited copper foil applied as a negative electrode current collector of a lithium ion secondary battery includes (a) an anode drum and a foil making device comprising a metal anode surrounding the anode drum step; (b) between the cathode drum and the metal anode, as an additive to an aqueous copper sulfate solution having a copper concentration of 50 g/L to 120 g/L and a sulfuric acid concentration of 50 g/L to 160 g/L, in addition to brighteners, levelers, and suppressors, Cl 8-20 ppm and Flowing the electrolyte solution with the addition of Na ₂ So ₄ 200 ~ 400ppm; and (c) electrodepositing copper (Cu) on the surface of the anode drum at an electrolysis temperature of 30° C. to 60° C. and a current density of 40 ASD to 70 ASD.

At this time, 10 to 20 ppm of at least one of SPS (bis(3-sulfoproply)disulfide), MPS (mercapto-propane sulphonic acid), and DPS (3-N,N-dimethylaminodithiocarbamoyl-1-propanesulphonic acid) is added as the brightener , It is preferable to add 10 to 20 ppm of at least one of gelatin, collagen, and PEG (polyethylene glycol) as the leveler, and 5 to 10 ppm of HEC as the suppressor.

In addition, another aspect of the present invention includes a secondary battery negative electrode current collector coated with an anode active material on at least one surface of the electrodeposited copper foil, or a secondary battery in which the secondary battery negative electrode current collector is applied to the negative electrode.

The electrodeposited copper foil according to the present invention is optimal to be mainly used as an anode current collector of a secondary battery due to its characteristics, but it can also be used as a copper foil laminate for a printed wiring board. When the electrodeposited copper foil of the present invention is used as a negative electrode current collector of a secondary battery, particularly a lithium ion secondary battery, the adhesive strength with the negative electrode material is 20 N/m or more, thereby remarkably improving the adhesion between the negative electrode current collector and the negative electrode active material.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the detailed description of the present invention to be described later, so that the present invention is described in such drawings should not be construed as being limited only to
1 is a cross-sectional view of a foil making device for electrodeposition of an electrodeposited copper foil.
2 is a profile graph defining Rsm, which is a surface roughness parameter.
3 is a cross-sectional view illustrating a state in which a protective layer is coated on the surface of an electrodeposited copper foil according to an embodiment of the present invention.
4 is a cross-sectional view showing a state in which an electrodeposited copper foil is adhered to a slide glass in order to measure the adhesive strength of the electrodeposited copper foil with an anode material according to an embodiment of the present invention.
5 is a cross-sectional view illustrating a state in which the adhesive strength of an electrodeposited copper foil adhered to a slide glass with an anode material is measured using UTM equipment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention. Accordingly, the embodiments described in the present specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. It should be understood that there may be equivalents and variations.

The electrodeposited copper foil for a lithium ion secondary battery according to an embodiment of the present invention is preferably used as a negative electrode current collector of a lithium ion secondary battery. That is, in a lithium ion secondary battery, an electrodeposited copper foil is preferably used as a negative electrode current collector coupled to the negative electrode active material.

On the other hand, in the manufacture of a lithium ion secondary battery, a foil made of aluminum (Al) is generally used as a positive electrode current collector combined with a positive electrode active material.

Accordingly, in the present invention, a case in which the electrodeposited copper foil for a lithium ion secondary battery corresponds to a negative electrode current collector applied to a lithium secondary battery will be described as an example.

The electrodeposited copper foil for a lithium ion secondary battery according to an embodiment of the present invention is manufactured by the foil making device of FIG. 1 , and has a glossy surface (S surface) in contact with the negative electrode drum 12 and a matte surface (M surface) on the opposite side. In general, the glossy surface of the electrodeposited copper foil has its surface characteristics determined by the method of grinding the cathode drum 12, and the matte surface (M surface) is the electrolytic condition of the current density, flux, liquid temperature, electrolyte, and additives in the foil making process. The surface characteristics are determined according to the type and content.

The electrodeposited copper foil according to an embodiment of the present invention is characterized in that Rsm (see FIG. 2) defined as the average width of the profile elements of the mat surface is 50 μm or more and 125 μm or less.

Referring to FIG. 2 , the average width Rsm of the unevenness is defined as an arithmetic average value of the width Xs of the unevenness, which is a profile element, as shown in Equation 1 below.

When the average width of the profile elements Rsm of the mat surface of the electrodeposited copper foil according to an embodiment of the present invention is less than 50㎛ or exceeds 125㎛, the adhesion between the electrodeposited copper foil as the negative electrode current collector and the negative electrode active material is 20N /m is less than the adhesion force with the negative electrode active material required by the negative electrode current collector does not satisfy the desired standard.

This is because, when the Mean width of the profile elements Rsm is less than 50㎛, the active material particles are spread between the acid and the acid of the unevenness to cause line contact, and when it exceeds 125㎛, the active material particles are This is because line contact occurs as well because it is loosely captured in the valley between the mountains and is not tightly enclosed.

Therefore, in order for the surface adhesion between the electrodeposited copper foil used as a negative electrode current collector for lithium ion secondary batteries and the negative electrode active material to be at least 20 N/m, the negative electrode active material particles are tightly trapped between the acid and the acid of the surface unevenness of the electrodeposited copper foil. Since contact should occur, the average width of the profile elements Rsm of the mat surface of the electrodeposited copper foil should be 50㎛ or more and 125㎛ or less.

On the other hand, the electrodeposited copper foil 1 (ie, raw foil or raw foil) for a lithium ion secondary battery according to an embodiment of the present invention may form a protective layer 2 on its surface as shown in FIG. 3 .

The protective layer 2 is selectively formed on the surface of the electrodeposited copper foil to protect the surface of the electrodeposited copper foil 1 for lithium ion secondary batteries, and contains at least one selected from chromium (Cr), a silane coupling agent, and BTA (benzotriazole). include Preferably, the protective layer 2 is preferably a chromate anti-rust layer. Hereinafter, the electrodeposited copper foil in which the protective layer 2 is formed on the surface of the electrodeposited copper foil 1 is defined as a surface-treated electrodeposited copper foil in order to distinguish it from the original foil.

The surface-treated electrodeposited copper foil according to an embodiment of the present invention should also have a mean width of the profile elements Rsm of 50 μm or more and 125 μm or less of the mat surface.

In addition, the thickness of the surface-treated electrodeposited copper foil according to an embodiment of the present invention is preferably 3 to 20 μm. When the thickness is less than 3 μm, there is a problem in handling the copper foil, and when it exceeds 20 μm, the battery is designed leads to an increase in size and weight.

In addition, the electrolytic raw foil or surface-treated electrodeposited copper foil according to an embodiment of the present invention preferably has a tensile strength of 25 to 70 kgf/mm2. There is a problem in stability, and when it exceeds 70kgf/mm2, the copper foil brittles and tearing by a notch may be a problem.

By coating a negative active material on at least one surface of the surface-treated electrodeposited copper foil of FIG. 3 according to an embodiment of the present invention to prepare a negative electrode current collector for a lithium secondary battery, and applying the negative electrode current collector to the negative electrode, a lithium ion secondary battery can be manufactured.

< Example and comparative example >

Hereinafter, the characteristics of the present invention will be more clearly examined by preparing the electrodeposited copper foils of Examples satisfying the characteristics of the present invention and comparative examples compared thereto, and comparing the physical properties between the electrodeposited copper foils of this Example and Comparative Examples.

Electrolytic copper foils for lithium ion secondary batteries according to Examples and Comparative Examples are manufactured using a foil making device as shown in FIG. 1 having a structure including a negative electrode drum in an electrolytic cell and a positive electrode plate positioned with a predetermined interval with respect to the negative electrode drum. At this time, the distance between the positive plate and the negative drum can be adjusted in the range of approximately 5 to 20 mm, and the standard deviation of the interval should be controlled within 2 mm.

In addition, copper sulfate may be used as the electrolyte used, and as an additive, a brightener to give gloss to the plating surface and obtain a fine plating layer, a leveler to obtain a copper foil of low illumination, and a surf to implement stable low illumination Copper foil is electrodeposited on the anode drum by appropriately mixing a suppressor or the like to prepare an original foil.

The composition of the copper sulfate electrolyte for manufacturing an electrodeposited copper foil according to an embodiment of the present invention includes 50 to 120 g/L of copper and 50 to 160 g/L of sulfuric acid, and the brightener is a sulphonate-based sulfide containing sulfide. For example, 10 to 20 ppm of any one or more of SPS (bis (3-sulfoproply) disulfide), MPS (mercapto-propane sulphonic acid), and DPS (3-N,N-dimethylaminodithiocarbamoyl-1-propanesulphonic acid) is added, Leveler adds 10 to 20 ppm of any one or more of gelatin, collagen, and PEG (polyethylene glycol) having a low molecular weight of 1,000 to 100,000, and adds 5 to 10 ppm of HEC (Hydroxyethyl cellulose) as a suppressor, and chlorine ( Cl) 8-20ppm, Na ₂ So ₄ 200-400ppm is added.

In addition, under these electrolyte composition and additive composition conditions, the current density is in the range of 40ASD to 70ASD and the temperature of the electrolyte is in the range of 30 to 60 ℃ to prepare the electrolytic original foil (1), and chromate treatment on both sides of the original foil (1) A surface-treated electrodeposited copper foil for a lithium secondary battery corresponding to the embodiment is manufactured by forming the protective layer 2 of FIG.

On the other hand, in order to manufacture the electrodeposited copper foil for a lithium secondary battery corresponding to the comparative example, a method different from the manufacturing method of the above-described embodiment is applied, and specifically, the type and content of additives added to copper sulfate used as an electrolyte in the manufacturing process. to prepare an electrolytic original foil as shown in [Table 1] below, and to prepare a surface-treated electrodeposited copper foil for a lithium secondary battery corresponding to a comparative example by forming a protective layer.

The specific electrolyte composition and electrolysis conditions for manufacturing the surface-treated electrodeposited copper foil according to Examples and Comparative Examples are as follows.

Copper: 70~80g/L

Sulfuric acid : 80~110g/L

Electrolyte temperature: 30~60℃

Current density: 40~70ASD

Leveler: Collagen

Brightner: SPS

Suppressor: HEC

Other additives: Cl, Na ₂ So ₄

Cu
[g/L] H2SO4
[g/L] current density
[ ASD ] SPS
[ppm] Collagen
[ppm] HEC
[ppm] Cl
[ppm] Na ₂ So ₄
[ppm] Example One 70 80 40 10 15 10 20 320 Example 2 80 110 50 10 10 5 18 400 Example 3 80 80 70 20 10 10 8 350 Example 4 70 120 70 20 20 8 18 200 comparative example One 70 80 40 10 10 5 8 1,500 comparative example 2 80 110 50 50 30 30 30 800 comparative example 3 70 110 70 15 10 10 40 900 comparative example 4 80 100 60 50 10 5 30 1,500 comparative example 5 80 100 60 20 30 5 30 1,500

The tensile strength of the surface-treated electrodeposited copper foil prepared under the above-described conditions and the Rsm, M-plane adhesion and S-surface adhesion to the matte surface (M surface) and glossy surface (S surface) were measured respectively, and the following [ Table 2].

of electrolytic copper foil performance evaluation

1) Average width of irregularities ( Rsm )

The surface roughness parameter Rsm is measured according to the method and definition prescribed in JIS B0601:2001 (ISO4287:1997).

2) Tensile strength

Measurement method: Specimen (width: 12.7mm, length: 150mm), gage distance: 50mm, cross head speed: 50mm/min

Measuring device: UTM (shamdzu)

3) with anode material adhesion

① Specimen preparation: A negative active material slurry was prepared by using SDK's Si/C composite (650 mAh/g) as an active material and SBR (Styrene-butadiene rubber) and CMC (Carboxy Methyl Cellulose) as an additive in a composition of 98:2:1, respectively. prepared, coated on the matte and glossy surfaces of the surface-treated electrodeposited copper foils of Examples and Comparative Examples prepared in [Table 1] at a loading amount of 9 to 12 mg/cm 2 , respectively, and dried at 110° C. for 10 minutes, followed by a roll press. Proceed to prepare specimens for each of Examples and Comparative Examples. At this time, the electrode density of the negative electrode is 1.5 to 1.8 g/cm 3 .

② Adhesion strength measurement: After heat-treating the specimen 40 prepared in this way at 190° C. for 1 hour or more, cutting it into a width of 200 mm and a length of 100 mm, as shown in FIG. It is attached to the slide glass (60) by using it. Thereafter, as shown in FIG. 5 , the force required to pull at a 90 degree angle is measured using a UTM device as a load cell: 10N and a measurement speed: 50 mm/min. At this time, if the adhesive strength is 20mN/mm or more, separation between the anode current collector and the active material does not occur during charging and discharging of the battery, and when the adhesive strength is less than 20mN/mm, separation between the anode current collector and the active material may occur during charging and discharging, so that the battery capacity is stable. cannot be maintained as

Rsm[㎛] tensile strength
[kgf/㎟] M side adhesion
[N/m] S surface adhesion
[N/m] M side S side Example 1 50 55 52 24 21 Example 2 80 33 33 23 22 Example 3 125 53 50 25 23 Example 4 98 52 30 23 21 Comparative Example 1 46 52 34 16 20 Comparative Example 2 153 51 33 14 22 Comparative Example 3 48 50 34 17 21 Comparative Example 4 130 125 35 16 23 Comparative Example 5 35 50 38 15 23

Referring to [Table 2], the electrodeposited copper foil of Examples and the electrodeposited copper foil of Comparative Examples both have a tensile strength of 25 to 70 kgf / mm 2 , and the physical properties are the same in that the adhesion of the glossy surface (S surface) is 20 N / m or more. However, in the electrodeposited copper foils of Examples and Comparative Examples, the Rsm of the M-plane is different due to the different types and contents of additives added during the foil making process, and thus the M-plane adhesion is different as shown in [Table 2].

That is, in the electrodeposited copper foils of Examples 1 to 4, the Rsm of the M side has a surface roughness value of 50 to 125 μm, and thus the M side adhesion force greatly exceeds 20 N/m, whereas those of Comparative Examples 1 to 5 The electrodeposited copper foil has an M-plane Rsm of less than 50 μm (Comparative Example 1, Comparative Example 3, Comparative Example 5) or exceeding 125 μm (Comparative Example 2, Comparative Example 4), so that the M-plane adhesion is significantly less than 20 N/m, and there is.

In the above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited thereto and will be described below with the technical idea of the present invention by those of ordinary skill in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims.

11: metal anode
12: cathode drum
13: electrolyte
14: Electrolytic copper foil (original foil)

Claims (13)

As an electrodeposited copper foil applied as a negative electrode current collector of a lithium ion secondary battery,
Electrolytic copper foil, characterized in that the surface roughness of the mat surface (M surface) of the electrodeposited copper foil is 50㎛ or more and 125㎛ or less in Rsm. The method of claim 1,
Electrolytic copper foil, characterized in that the chromate protective layer is formed on the matte or glossy surface of the electrodeposited copper foil. 3. The method of claim 2,
Electrolytic copper foil, characterized in that the tensile strength of the electrodeposited copper foil is 25 ~ 70kgf / ㎟. 3. The method of claim 2,
Electrolytic copper foil, characterized in that the thickness of the electrodeposited copper foil is 3 to 20㎛. A secondary battery negative electrode current collector, characterized in that the negative electrode active material is coated on at least one surface of the electrodeposited copper foil according to claim 2. A secondary battery characterized in that the negative electrode current collector of the secondary battery of claim 5 is applied to the negative electrode. A method of manufacturing an electrodeposited copper foil applied as a negative electrode current collector of a lithium ion secondary battery, the method comprising:
(a) preparing a foil making apparatus comprising a cathode drum and a metal anode surrounding the cathode drum;
(b) between the cathode drum and the metal anode, the copper concentration is 50 g/L to 120 g/L, and the sulfuric acid concentration is 50 g/L to 160 g/L. 8 to 20 ppm and Na ₂ So ₄ flowing an electrolyte solution of 200 to 400 ppm; and
(c) electrodepositing copper (Cu) on the surface of the anode drum at an electrolysis temperature of 30° C. to 60° C. and a current density of 40 ASD to 70 ASD of the electrolyte method. 8. The method of claim 7,
As the brightener, 10 to 20 ppm of any one or more of SPS (bis(3-sulfoproply)disulfide), MPS (mercapto-propane sulphonic acid), and DPS (3-N,N-dimethylaminodithiocarbamoyl-1-propanesulphonic acid) is added A method for manufacturing an electrolytic copper foil. 9. The method according to claim 7 or 8,
A method of manufacturing an electrolytic copper foil, characterized in that 10 to 20 ppm of at least one of gelatin, collagen, and PEG (polyethylene glycol) is added as the leveler. 10. The method of claim 9,
A method of manufacturing an electrolytic copper foil, characterized in that by adding 5 to 10 ppm of HEC (Hydroxyethyl cellulose) as the suppressor. 11. The method of claim 10,
Method for producing an electrodeposited copper foil, characterized in that it further comprises the step of chromate anti-rust treatment on the matte or glossy surface of the electrodeposited copper foil. Copper sulfate having a copper concentration of 50 g/L to 120 g/L and a sulfuric acid concentration of 50 g/L to 160 g/L between the cathode drum and the metal anode of a foil making apparatus comprising a cathode drum and a metal anode surrounding the cathode drum Any one or more of SPS (bis(3-sulfoproply)disulfide), MPS (mercapto-propane sulphonic acid), DPS (3-N,N-dimethylaminodithiocarbamoyl-1-propanesulphonic acid) as an additive in aqueous solution 10-20ppm, gelatin, collagen , 10 to 20 ppm of any one or more of PEG (Polyethylene glycol), 5 to 10 ppm of HEC (Hydroxyethyl cellulose), 8 to 20 ppm of chlorine (Cl), and 200 to 400 ppm of Na ₂ So ₄ While flowing the electrolyte, the electrolysis temperature of the electrolyte In the electrolytic copper foil produced by electrodepositing copper (Cu) on the surface of the negative electrode drum with a 30 ℃ to 60 ℃ and a current density of 40 ASD to 70 ASD,
Electrolytic copper foil, characterized in that the surface roughness of the mat surface (M surface) of the electrodeposited copper foil is 50㎛ or more and 125㎛ or less in Rsm. 13. The method of claim 12,
Electrolytic copper foil, characterized in that the chromate protective layer is formed on the matte or glossy surface of the electrodeposited copper foil.

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