TW202009327A - Copper foil with minimized bagginess, wrinkle or tear, electrode including the same, secondary battery including the same and method for manufacturing the same - Google Patents

Abstract

Disclosed is a copper foil including a copper layer and having a tensile strength of 29 to 65 kgf/mm2, a mean width of roughness profile elements (Rsm) of 18 to 148 µm and a texture coefficient bias [TCB(220)] of 0.52 or less..

Description

Copper foil minimizing ridges, wrinkles or tears, electrodes containing the same, secondary batteries containing the same, and methods of manufacturing the same

The present invention relates to a copper foil that minimizes bumps, wrinkles, or tears, an electrode including the same, a secondary battery including the same, and a method of manufacturing the same.

Electrolytic copper foil is used to manufacture various products, such as the negative electrode of secondary batteries and flexible printed circuit boards (FPCBs).

Among them, copper foil manufactured by electroplating is called "electrolytic copper foil". Such electrolytic copper foil is usually manufactured by a roll-to-roll (RTR) process, and is used to manufacture anodes for secondary batteries and flexible printed circuit boards (FPCB) through an RTR process. Because the RTR process can be continuously produced, the RTR process is suitable for large-scale production. However, during the RTR process, when the copper foil is folded, torn, or encounters bagginess or wrinkles, the operation of the RTR device should be stopped until the problems are resolved before the device is operated, which leads to Production efficiency decline.

In particular, when the copper foil is used to manufacture a secondary battery, it is difficult to stably manufacture the product when the copper foil swells, wrinkles, or tears. Therefore, the bumps, wrinkles, or tears that occur in the copper foil during the manufacturing of the secondary battery can lead to a reduction in the manufacturing yield of the secondary battery and an increase in the manufacturing cost of the product.

It is known to remove bumps, wrinkles and tearing defects in copper foil by controlling the weight deviation of copper foil to a low level. However, controlling only the weight deviation of the copper foil has limitations for problems such as swell, wrinkles, and tears that occur during secondary battery manufacturing. In particular, recently, in order to increase the capacity of secondary batteries, more and more ultra-thin copper foils are used, for example, copper foils with a thickness of 8 μm or less are used as anode current collectors. In this case, even if the weight deviation of the copper foil is accurately controlled, defects such as bumps, wrinkles, and tears may occur intermittently during the manufacturing of the secondary battery. Therefore, it is necessary to prevent or suppress the bulging, wrinkling, or tearing of the copper foil during the manufacturing of the secondary battery.

Therefore, in view of the above problems, an object of the present invention is to provide a copper foil, an electrode including the same, a secondary battery including the same, and a method of manufacturing the same.

Another object of the present invention is to provide a copper foil with minimal ridges, wrinkles or tears. In particular, another object of the present invention is to provide a copper foil that can prevent the occurrence of ridges, wrinkles, or tears in the process of manufacturing a secondary battery with a small thickness, thus having excellent roll-to-roll (RTR) ) Processability.

Another object of the present invention is to provide an electrode for a secondary battery including a copper foil and a secondary battery including an electrode for a secondary battery.

Another object of the present invention is to provide a flexible copper foil laminated film including copper foil.

Another object of the present invention is to provide a method of manufacturing copper foil, which can prevent bulging, wrinkling, or tearing during the manufacturing process.

In addition to the above-mentioned aspects of the present invention, other features and advantages of the present invention will be described below, and those skilled in the art will clearly understand other features and advantages of the present invention from the description.

According to the present invention, can be achieved by providing the above copper foil and other objects, comprising a copper layer having a tensile strength of 29kgf / mm ² to 65kgf / mm ^2, and a roughness of 18μm to 148μm the contour element (Rsm) of a The average width, and a texture coefficient deviation of 0.52 or less [TCB(220)].

The copper foil may further include a corrosion-resistant film disposed on the copper layer.

The anticorrosive film may contain at least one of chromium (Cr), a silane compound, or a nitrogen compound.

The copper foil may have a maximum height roughness (Rmax) of 0.6 μm or more.

The copper foil may have a weight deviation of 5% or less.

The copper foil may have an elongation of 2% or higher at room temperature of 25±15°C.

A thickness of the copper foil may be 4 μm to 30 μm.

According to another aspect of the present invention, there is provided an electrode for a secondary battery, comprising the copper foil of the present invention; and an active material layer provided on the copper foil.

According to another aspect of the present invention, there is provided a secondary battery including a cathode; an anode facing the cathode; an electrolyte to provide an environment in which ions can move between the cathode and the anode; and A separator for electrically insulating the cathode and the anode, wherein the anode includes the copper foil of the present invention; and an active material layer disposed on the copper foil.

According to another aspect of the present invention, there is provided a flexible copper foil laminate film comprising a polymer film; and the copper foil of the present invention disposed on the polymer film.

According to another aspect of the present invention, there is provided a method of manufacturing copper foil, the method comprising: providing an electrode plate and a rotating electrode drum (rotating electrode drum) spaced apart from each other in an electrolyte containing copper ions The current density is 30A/dm ² to 80A/dm ² to form a copper layer; wherein the electrolyte contains 70g/L to 100g/L copper ions; 80g/L to 130g/L sulfuric acid; 2mg/L to 20 mg/L of 2-mercaptothiazoline (2-mercaptothiazoline); 2 mg/L to 20 mg/L of bis-(3-sulfopropyl) disulfide (SPS); and 50 mg/L L or less polyethylene glycol (PEG).

The electrolyte may contain 10 mg/L to 30 mg/L of chlorine (Cl).

The flow rate deviation of the electrolyte per unit time (second) may be 5% or less.

The general description of the present invention given above is for illustration or description only, and should not be construed as limiting the scope of the present invention.

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are shown in the drawings.

Those skilled in the art will understand that various modifications, additions and substitutions can be made without departing from the scope and spirit of the invention disclosed in the appended patent application. Therefore, the present invention includes the disclosure defined in the scope of the patent application and the modifications and changes falling within the scope of equivalents thereof.

The shapes, sizes, ratios, angles, and numbers disclosed in the drawings for describing the embodiments of the present invention are merely examples, and thus the present invention is not limited to the details shown. Throughout the description, the same reference numerals refer to the same elements.

In the case of using "include", "have" and "include" described in this specification, another part may exist unless "only" is used. Unless otherwise stated, singular terms may include plural forms. In constructing an element, although not explicitly described, the element is interpreted as including an error range.

When describing the positional relationship, for example, when the positional order is described as "upper", "upper", "lower", and "next", it may include the situation where there is no contact between them, unless "only" or "direct" is used.

When describing temporal relationships, for example, when the chronological order is described as "after", "follow-up", "next", and "before", discontinuities may be included unless "exactly" or "direct" is used.

It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element without departing from the scope of the present invention.

It should be understood that the term "at least one" includes all combinations related to any one item.

The features of various embodiments of the present invention may be partially or wholly coupled with each other or may be partially or wholly combined with each other, and may be mutually interoperable differently and technically driven, as those skilled in the art can fully understand. The embodiments of the present invention may be performed independently of each other, or may be performed together in a mutually dependent relationship.

FIG. 1 is a schematic cross-sectional view showing a copper foil 100 according to an embodiment of the present invention.

Referring to FIG. 1, the copper foil 100 includes a copper layer 110. According to an embodiment of the present invention, the copper foil may further include an anti-corrosion film 210 disposed on the copper layer 110. The anti-corrosion film 210 may be omitted.

According to an embodiment of the present invention, the copper layer 110 has a matte surface MS and a matte surface SS opposite to the matte surface SS.

For example, the copper layer 110 may be formed on the rotating electrode drum by electroplating (see FIG. 8). At this time, the glossy surface SS refers to the surface of the copper layer 110 that is in contact with the rotating electrode drum during the electroplating process, and the matte surface MS refers to the surface opposite to the glossy surface SS.

The glossy surface SS generally has a lower surface roughness Rz than the matte surface MS, but the embodiments of the present invention are not limited thereto. The surface roughness Rz of the glossy surface SS may be equal to or higher than the surface roughness Rz of the matte surface MS.

The anticorrosive film 210 may be provided on at least one of the matte surface MS or the glossy surface SS of the copper layer 110. Referring to FIG. 1, the anticorrosive film 210 is provided on the matte surface MS, but the embodiment of the present invention is not limited thereto. That is, the anti-corrosion film 210 may be provided only on the glossy surface SS, or on both the matte surface MS and the glossy surface SS.

The anticorrosive film 210 protects the copper layer 110. The anticorrosive film 210 can prevent the copper layer 110 from being oxidized or denatured during storage. Therefore, when the anti-corrosion film 210 is not provided on the copper layer 110, the surface of the copper layer 110 is oxidized over time, and thus the life of the device (for example, a secondary battery including the copper foil 100) may be deteriorated. The anti-corrosion film 210 is also called "protective layer". The anti-corrosion film 210 is not particularly limited, as long as it can protect the copper layer 110, any film or layer can be used as the anti-corrosion film 210.

According to an embodiment of the present invention, the anti-corrosion film 210 may include at least one of chromium (Cr), a silane compound, or a nitrogen compound.

For example, the anti-corrosion film 210 may be prepared from an anti-corrosion liquid containing chromium (Cr), that is, an anti-corrosion liquid containing a chromate compound.

According to an embodiment of the present invention, the copper foil 100 has a first surface S1 that is a surface based on the direction of the matte surface MS of the copper layer 110 and a second surface S2 that is a direction of the glossy surface SS. In FIG. 1, the first surface S1 of the copper foil 100 is the surface of the anticorrosive film 210, and the second surface S2 is the glossy surface SS. When the anti-corrosion film 210 is not provided on the copper layer 110, the matte surface of the copper layer 110 corresponds to the first surface S1 of the copper foil 100.

According to an embodiment of the present invention, the texture coefficient bias (TCB) of the copper foil 100 is 0.52 or less.

More specifically, the deviation of the texture coefficient of the (220) plane of the copper foil 100 [TCB(220)] is 0.52 or less. According to an embodiment of the present invention, the texture coefficient deviation [TCB (220)] of the (220) plane of the copper foil 100 is also referred to as the texture coefficient deviation [TCB (220)] of the copper foil 100.

The (220) plane texture coefficient deviation [TCB(220)] represents the position-dependent deviation or trend of the (220) plane [TC(220)] texture coefficient. The texture coefficient deviation [TCB(220)] relates to the crystal structure of the surface of the copper foil 100. (220) The plane texture coefficient deviation [TCB(220)] can be calculated according to Equation 1. Specifically, the texture coefficient deviation [TCB(220)] of the (220) plane is measured three times at various points on the left, center, and right in the width direction of the copper foil 100 (see Equation 2 below). Among them, the highest [TC(220)] value is TC _max , and the lowest [TC(220)] value is TC _min . The texture coefficient deviation [TCB(220)] is calculated from the difference between TC _max and TC _min , that is, the value of "TC _max -TC _min ".

[Equation 1]

Texture coefficient deviation [TCB(220)] = TC _max -TC _min

Meanwhile, the standard for collecting the sample in the width direction of the copper foil 100 may be the same as the standard for measuring the weight deviation.

According to Equation 1, the texture coefficient deviation [TCB(220)] of the (220) plane is obtained from the texture coefficient [TC(220)] of the (220) plane.

Hereinafter, referring to FIG. 2, a method for measuring and calculating the texture coefficient [TC(220)] of the (220) plane according to an embodiment of the present invention will be described below.

Fig. 2A shows an example of the XRD pattern of the copper foil. More specifically, FIG. 2A is an XRD pattern of copper foil 100.

In order to measure the texture coefficient of the (220) plane [TC(220)], first, by performing X-ray diffraction (XRD) within a diffraction angle of 30° to 95° [target: copper K α1, 2θ interval: 0.01°, and 2θ scan rate: 3 degrees/min] obtain an XRD pattern with peaks corresponding to n crystal planes. For example, as shown in FIG. 2A, XRD patterns corresponding to peaks in the (111), (200), (220), and (311) planes are obtained. 2A, n is 4.

Then, the XRD diffraction intensity [I(hkl)] of each crystal plane (hkl) is obtained from the XRD pattern. In addition, the XRD diffraction intensity [I ₀ (hkl)] of n crystal planes of the standard copper powder specified by the Joint Committee on Powder Diffraction Standards (JCPDS) was obtained. Next, obtain the arithmetic average of I(hkl)/I ₀ (hkl) of n crystal planes, and then calculate by dividing the I(220)/I ₀ (220) of the (220) plane by the arithmetic average (220) Texture coefficient of the plane [TC(220)]. That is, the texture coefficient [TC(220)] of the (220) plane will be calculated based on the following Equation 2:

[Equation 2]

According to an embodiment of the present invention, the (220) plane of the copper foil 100 may have a texture coefficient deviation of 0.52 or less [TCB (220)]. More specifically, the copper foil 100 may have a texture coefficient of 0.52 or less [TC(220)].

When the deviation of the texture coefficient (TCB) of the (220) plane is higher than 0.52, due to the difference in the local texture caused by the difference in the local crystal structure, tension is applied during the copper foil 100 manufacturing process of the copper foil through the roll-to-roll process The copper foil easily deforms, so wrinkles are generated.

According to an embodiment of the present invention, the texture coefficient [TC(220)] of the (220) plane should be kept at a relatively low level less than 0.52.

According to an embodiment of the present invention, the tensile strength of the copper foil 100 is 29 kgf/mm ² to 65 kgf/mm ² . The tensile strength can be measured with a universal testing machine (UTM) according to the provisions of the IPC-TM-650 test method manual. According to the embodiment of the present invention, the tensile strength can be measured with the universal testing machine of Instron. At this time, the width of the sample used to measure the tensile strength was 12.7 mm, the distance between the clamps was 50 mm, and the measurement speed was 50 mm/min. In order to evaluate the physical properties, the tensile strength of the sample was repeatedly measured three times, and the average value was used as the tensile strength of the copper foil 100.

When the tensile strength of the copper foil 100 is less than 29 kgf/mm ² , the copper foil 100 cannot withstand forces such as the tension applied to the copper foil during the manufacturing process, so it may swell during the roll-to-roll process.

When the tensile strength of the copper foil 100 is higher than 65 kgf/mm ² , due to its excellent tensile strength, the copper foil 100 can fully withstand the forces such as the tension applied to it during the manufacturing process, however, the copper foil 100 Due to its increased brittleness, it cannot be elongated in response to the force locally applied to it during the roll-to-roll process and may be torn. Therefore, the availability of the copper foil 100 deteriorates. For example, tearing may occur during the preparation of copper foil or during the manufacturing of electrodes for secondary batteries using copper foil, making it difficult to obtain products stably.

For example, when such tearing occurs during the manufacturing of copper foil through a roll-to-roll process, the operation of the roll-to-roll process equipment should be stopped and the copper foil torn portion removed before operating the equipment. In this case, the processing time and cost increase and the production efficiency deteriorates.

According to an embodiment of the present invention, the copper foil 100 has an average width of roughness profile elements (Rsm) of 18 μm to 148 μm.

The average width of the roughness profile element (Rsm) can be measured by a roughness tester according to JIS B 0601-2001. Specifically, according to an embodiment of the present invention, the average width of the roughness profile element (Rsm) can be measured with a SJ-310 type measuring instrument commercially available from Mitutoyo Corporation. At this time, the measurement length excluding the cut length is set to 4 mm, and the cut length is set to 0.8 mm at the beginning stage and the later stage. In addition, the radius of the tip of the stylus is set to 2 μm.

Figure 2B is a graph of roughness contour elements.

Referring to FIG. 2B, the average width of the roughness profile element (Rsm) is the distance from the point where a peak (valley) crosses the average line ML to the corresponding point of the adjacent peak (valley) (XSi, where i = 1, 2, 3. The arithmetic mean of...m). Specifically, the average width of the roughness profile element (Rsm) can be calculated by the following equation 3:

[Equation 3]

The average width of the roughness profile element (Rsm) is suitable for evaluating surfaces with regular textures.

When the average width of the roughness profile element (Rsm) is less than 18 μm, in the process of manufacturing the copper foil 100 by rolling, there is a high possibility that the tension is concentrated on a certain peak or valley. Because there are too many peaks (valleys) on the surface of the copper foil 100, the copper foil 100 may be easily torn.

On the other hand, when the average width of the roughness profile element (Rsm) is higher than 148 μm, slippage easily occurs in the process of manufacturing the copper foil 100 through the roll-to-roll process because the distance between adjacent peaks is large , Making the copper foil 100 easy to wrinkle.

According to an embodiment of the present invention, the copper foil 100 has a maximum height roughness (Rmax) of 0.6 μm or more.

The maximum height roughness (Rmax) can be measured by a roughness tester according to JIS B 0601-2001. Specifically, the maximum height roughness (Rmax) can be measured with a SJ-310 type measuring instrument commercially available from Mitutoyo. Specifically, the measurement length excluding the cut-off length is set to 4 mm, and the cut-off length is set to 0.8 mm at the beginning and later stages. In addition, the radius of the tip of the stylus is set to 2 μm, and the measured pressure is 0.75 mN.

In the case where the maximum height roughness (Rmax) is less than 0.6 μm, since the weight of the copper foil 100 overlaps, when the copper foil 100 is wound on a bobbin or winder, the copper foil 100 may be locally elongated and generated Bulge (bagginess).

According to an embodiment of the present invention, the copper foil 100 may have a maximum height roughness (Rmax) of 3.5 μm or less. When the maximum height roughness (Rmax) of the copper foil 100 is higher than 3.5 μm, in the process of manufacturing the copper foil 100 by the roll-to-roll (RTR) process, air will be trapped when the copper foil 100 is wound on a bobbin or winder Trapped between the copper foil to make the copper foil bulge.

According to an embodiment of the present invention, the copper foil 100 has a weight deviation of 5% or less. More specifically, the copper foil 100 may have a weight deviation of 0 to 5%. In this case, zero weight deviation means no weight deviation.

According to the embodiment of the present invention, the weight deviation can be obtained by the average value (average weight) of the weight values measured at three arbitrary points in the width direction of the copper foil 100 and the standard deviation of the weight values. Specifically, samples of 5 cm×5 cm were obtained at three points arranged along the width direction of the copper foil 100, that is, the weight of each sample was measured in a direction perpendicular to the winding direction (transverse direction (TD)) Calculate the weight per unit area, calculate the "average weight" and "standard weight deviation" at three points based on the weight per unit area of the three samples, and calculate the weight deviation according to Equation 4 below:

[Equation 4]

In the case where the weight deviation of the copper foil 100 is higher than 5%, it may be partially elongated when the copper foil 100 is wound during the roll-to-roll process due to the overlap of the weight applied to the copper foil 100 The bump of the copper foil 100.

According to an embodiment of the present invention, the copper foil 100 has an elongation of 2% or more at room temperature of 25±15°C. The elongation can be measured with a universal testing machine (UTM) according to the provisions of the IPC-TM-650 test method manual. According to the embodiment of the present invention, the elongation can be measured with the universal testing machine of Instron. At this time, the width of the sample for measuring the elongation is 12.7 mm, the distance between the clamps is 50 mm, and the measurement speed is 50 mm/min. In order to evaluate the physical properties, the elongation of the sample was repeatedly measured three times, and the average value was taken as the elongation of the copper foil 100.

When the elongation of the copper foil 100 is less than 2%, the copper foil 100 will not be elongated in response to the force applied in the process of manufacturing the copper foil 100, so it will be torn.

More specifically, the copper foil 100 may have an elongation of 2% to 20%.

According to an embodiment of the present invention, the copper foil 100 may have a thickness of 4 μm to 30 μm. When the thickness of the copper foil 100 is less than 4 μm, in the process of manufacturing the copper foil 100 or a product (for example, an electrode for a secondary battery or a secondary battery) using the copper foil 100, workability may deteriorate. When the thickness of the copper foil 100 is higher than 30 μm, the thickness of the electrode for secondary batteries using the copper foil 100 increases, and it is difficult to realize a high-capacity secondary battery due to its thickness.

According to one embodiment of the invention, bagginess is different from wrinkle.

FIG. 9 is an image showing the bulge of copper foil. The portion indicated by the arrow (↗) in FIG. 9 indicates the area where the bulge occurs. According to an embodiment of the present invention, bulging refers to a state or part of the copper foil 100 that is locally elongated and unevenly distributed.

FIG. 10 is an image showing wrinkles of copper foil. The portion indicated by the arrow (↗) in FIG. 10 indicates the area where wrinkles appear. According to the embodiment of the present invention, the wrinkle refers to a state or part of the copper foil 100 that is partially folded.

However, an embodiment of the present invention is not limited to this, and ridges and wrinkles may not be distinguished, and ridges and wrinkles may have only a single meaning and may be used interchangeably. For example, the case where the copper foil 100 is partially elongated and not flat, and the case where the copper foil 100 is partially folded can be expressed as "swelling" or "wrinkle".

That is to say, "swelling" and "wrinkle" can not be used separately, but can have a meaning and are interchangeable.

FIG. 3 is a schematic cross-sectional view showing a copper foil 200 according to another embodiment of the present invention. In the following, the description of the constituent components described above will be omitted to avoid repetition.

Referring to FIG. 3, a copper foil 200 according to another embodiment of the present invention includes a copper layer 110, and two anti-corrosion films (anti-corrosion film 210 and anti-corrosion film 220). Glossy surface MS and glossy surface SS. Compared with the copper foil 100 shown in FIG. 1, the copper foil 200 shown in FIG. 3 further includes an anti-corrosion film 220 provided on the glossy surface SS of the copper layer 110.

For ease of description, in the anti-corrosion film 210 and the anti-corrosion film 220, the anti-corrosion film 210 provided on the matte surface MS of the copper layer 110 is referred to as a "first protective layer", and the anti-corrosion film 220 provided on the glossy surface SS It is called the "second protective layer".

In addition, the first surface S1 of the copper foil 200 shown in FIG. 3 is the same as the surface of the anticorrosive film 210 provided on the matte surface MS, and the second surface S2 is the same as the surface of the anticorrosive film 220 provided on the glossy surface SS the same.

According to another embodiment of the present invention, the anti-corrosion film 210 and the anti-corrosion film 220 may each include at least one of chromium (Cr), a silane compound, or a nitrogen compound.

The (220) plane of the copper foil 200 shown in FIG. 3 has a texture coefficient deviation [TCB (220)] of 0.52 or less.

Further, as shown in FIG. 3 the copper foil 200 has a tensile strength and an average width of 18μm to 148μm roughness profile element (Rsm) of 29 kgf / mm ² to 65kgf / mm ² in. In addition, the maximum height roughness (Rmax) of the copper foil 200 is 0.6 μm or more, the weight deviation is 5% or less, the elongation at room temperature of 25±15° C. is 2% or more, and the thickness is 4 μm to 30 μm.

4 is a schematic cross-sectional view showing an electrode 300 for a secondary battery according to another embodiment of the present invention.

The electrode 300 for a secondary battery shown in FIG. 4 can be applied to the secondary battery 500 shown in FIG. 6, for example.

Referring to FIG. 4, an electrode 300 for a secondary battery according to another embodiment of the present invention includes a copper foil 100 and an active material layer 310 provided on the copper foil 100. In this case, the copper foil 100 is used as a current collector.

More specifically, the electrode 300 for a secondary battery according to another embodiment of the present invention includes a copper foil 100 having a first surface S1 and a second surface S2, and the active material layer 310 is provided on the first surface S1 of the copper foil 100 Or at least one of the second surfaces S2. In addition, the copper foil 100 includes a copper layer 110 and an anti-corrosion film 210 provided on the copper layer 110.

FIG. 4 shows the copper foil 100 shown in FIG. 1 as a current collector. However, an embodiment of the present invention is not limited to this, and the copper foil 200 shown in FIG. 3 may be used as a current collector for the electrode 300 of a secondary battery.

In addition, FIG. 4 shows a configuration in which the active material layer 310 is provided only on the first surface S1 of the first surface S1 and the second surface S2 of the copper foil 100, but other embodiments of the present invention are not limited thereto. The active material layer 310 may be provided on the first surface S1 and the second surface S2 of the copper foil 100 or only on the second surface S2 of the copper foil 100.

The active material layer 310 shown in FIG. 4 includes electrode active materials, particularly anode active materials. That is, the electrode 300 for a secondary battery shown in FIG. 4 can be used as an anode.

The active material layer 310 may include at least one of carbon, a metal, a metal oxide, or a composite of metal and carbon. The metal may include at least one of germanium, tin, lithium, zinc, magnesium, cadmium, cerium, nickel, or iron. In addition, in order to increase the charge/discharge capacity of the secondary battery, the active material layer 310 may include silicon (Si).

When the copper foil 100 according to the embodiment of the present invention is used, the copper foil 100 is prevented from being torn, wrinkled, or raised during the process of manufacturing the electrode 300 for a secondary battery. Therefore, the manufacturing efficiency of the electrode 300 for the secondary battery can be improved, and the charge/discharge efficiency and capacity maintenance of the secondary battery including the electrode 300 for the secondary battery can be improved.

FIG. 5 is a schematic cross-sectional view showing an electrode 400 for a secondary battery according to another embodiment of the present invention.

The electrode 400 for a secondary battery according to another embodiment of the present invention includes a copper foil 200, and an active material layer 310 and an active material layer 320 provided on the copper foil 200.

Referring to FIG. 5, the copper foil 200 includes a copper layer 110 and anti-corrosion films 210 and 220 provided on the opposite surfaces MS and SS of the copper layer 110. In addition, the electrode 300 for a secondary battery shown in FIG. 5 includes an active material layer 310 and an active material layer 320 provided on both surfaces of the copper foil 200. Here, the active material layer 310 provided on the first surface S1 of the copper foil 200 is referred to as "first active material layer", and the active material layer 320 provided on the second surface S2 of the copper foil 200 is referred to as " The second active material layer."

Both the active material layer 310 and the active material layer 320 may be produced in the same way and using the same material, or in different ways and using different materials.

6 is a schematic cross-sectional view showing a secondary battery 500 according to another embodiment of the present invention. The secondary battery 500 shown in FIG. 6 is, for example, a lithium secondary battery.

6, the secondary battery 500 includes a cathode 370, an anode 340 facing the cathode 370, an electrolyte 350 disposed between the cathode 370 and the anode 340 to provide an environment in which ions can move, and electrically insulating the cathode 370 from the anode 340 (Isolated) of the isolation film 360. Here, the ions passing through the cathode 370 and the anode 340 are lithium ions. The separator 360 separates the cathode 370 from the anode 340 to prevent the current generated at one electrode from being unnecessarily consumed after moving to the other electrode via the secondary battery 500. Referring to FIG. 6, the separator 360 is provided in the electrolyte 350.

The cathode 370 includes a cathode current collector 371 and a cathode active material layer 372. The cathode current collector 371 is, for example, aluminum foil.

The anode 340 includes an anode current collector 341 and an active material layer 342. The active material layer 342 of the anode 340 includes an anode active material.

The copper foil 100 and the copper foil 200 shown in FIGS. 1 and 3 may be used as the anode current collector 341. In addition, the electrodes 300 and 400 for the secondary battery shown in FIGS. 4 and 5, respectively, may be used as the anode 340 of the secondary battery 500 shown in FIG. 6.

7 is a schematic cross-sectional view showing a flexible copper foil laminated film 600 according to another embodiment of the present invention.

The flexible copper foil laminated film 600 according to another embodiment of the present invention includes a polymer film 410 and a copper foil 100 provided on the polymer film 410. A flexible copper foil laminated film 600 including the copper foil 100 shown in FIG. 1 is shown in FIG. 7, but other embodiments of the present invention are not limited thereto. For example, the copper foil 200 shown in FIG. 3 or other copper foils may be used for the flexible copper foil laminated film 600.

The polymer film 410 is flexible and non-conductive. The type of polymer film 410 is not particularly limited. The polymer film 410 includes, for example, polyimide. The flexible copper foil laminated film 600 can be manufactured by laminating the polyimide film and the copper foil 100 by a roll press. Alternatively, the flexible copper foil laminated film 600 may be prepared by coating the copper foil 100 with a polyimide precursor solution and then heat-treating the resulting copper foil 100.

The copper foil 100 includes a copper layer 110 having a matte surface MS and a glossy surface SS, and an anti-corrosion film 210 provided on at least one of the matte surface MS and the glossy surface SS of the copper layer 110. In this case, the anti-corrosion film 210 may be omitted.

Referring to FIG. 7, the polymer film 410 is provided on the anti-corrosion film 210, but another embodiment of the present invention is not limited thereto. The polymer film 410 may be disposed on the glossy surface SS of the copper layer 110.

Hereinafter, a method for manufacturing the copper foil 200 according to another embodiment of the present invention will be described in detail with reference to FIG. 8.

FIG. 8 is a schematic diagram showing a method for manufacturing the copper foil 200 shown in FIG. 3.

First, a current density of 30 ASD (A/dm ² ) to 80 ASD (A/dm) is provided between an electrode plate 13 and a rotary electrode drum 12 (rotatary electrode drum) spaced apart from each other in an electrolyte 11 containing copper ions ² ) current to form the copper layer 110.

Specifically, referring to FIG. 8, when a current with a current density of 30 ASD to 80 ASD is applied to the electrode plate 13 and the rotating electrode drum 12 provided in the electrolytic cell 10 containing the electrolytic solution 11, by electrodeposition on the rotating electrode drum 12 (electrodeposition) of copper to form the copper layer 110. At this time, the gap between the electrode plate 13 and the rotating electrode drum 12 can be adjusted to the range of 8 mm to 13 mm.

As the current density applied to the electrode plate 13 and the rotating electrode drum 12 increases, the plating becomes uniform and the surface roughness of the matte surface MS of the copper layer 110 decreases accordingly. As the current density decreases, the electroplating becomes uneven, so the surface roughness of the matte surface MS of the copper layer 110 increases.

The electrolytic solution 11 contains 70 g/L to 100 g/L of copper ions and 80 g/L to 130 g/L of sulfuric acid. The temperature of the electrolyte 11 is maintained at 50°C to 70°C. In the electrolyte 11 having the above concentration, copper can be easily deposited on the rotating electrode drum 12.

In addition, the electrolyte 11 includes 2-mercaptothiazoline (2-mercaptothiazoline) of 2 mg/L to 20 mg/L as an organic substance, and bis-(3-sulfopropyl) disulfide of 2 mg/L to 20 mg/L ( bis-(3-sulfopropyl) disulfide (SPS) and polyethylene glycol (PEG) of 50 mg/L or less.

2-Mercaptothiazoline is called "MTZ" and can be represented by the following Structural Formula 1.

[Structure 1]

The function of 2-mercaptothiazoline (MTZ) is to refine the crystal grains during the preparation of the copper layer 110. When the concentration of 2-mercaptothiazoline (MTZ) in the electrolyte 11 is less than 2 mg/L, the fine grains formed by 2-mercaptothiazoline (MTZ) are insufficient, and the tensile strength of the copper foil 200 is less than 29 kgf/mm ² . On the other hand, when the concentration of 2-mercaptothiazoline (MTZ) is higher than 20 mg/L, the fine grains formed by 2-mercaptothiazoline (MTZ) are excessive, and the tensile strength of the copper foil 200 is higher than 65 kgf/mm ² .

When the concentration of bis-3-sulfopropyl disulfide (SPS) in the electrolyte 11 as a brightener is too high (ie, greater than 20 mg/L), the surface of the copper layer 110 will be excessively uniform, per unit width The number of peaks (valleys) is reduced, and the average width of the roughness profile elements (Rsm) of the copper foil 200 is higher than 148 μm. On the other hand, when the concentration of bis-(3-sulfopropyl) disulfide (SPS) is less than 2 mg/L, the surface of the copper layer 110 is unevenly uneven because the gloss concentration of the surface during copper plating is too low form. Therefore, the number of peaks (valleys) per unit width of the copper foil increases, and the average width of the roughness profile element (Rsm) is less than 18 μm.

Polyethylene glycol (PEG) is used to flatten the surface of the copper layer 110 during copper plating. Therefore, as the concentration of polyethylene glycol (PEG) in the electrolyte 11 increases, the uniformity of the copper layer 110 increases. When the concentration of polyethylene glycol (PEG) in the electrolyte 11 is higher than 50 mg/L, the surface uniformity of the copper foil 200 increases and the maximum height roughness (Rmax) of the copper foil 200 is less than 0.6 μm.

The electrolytic solution 11 contains 50 mg/L or less of silver (Ag). Here, silver (Ag) includes ions (Ag ⁺ ) dissociated in the electrolyte 11 and a non-dissociated form (Ag), and includes silver (Ag) in the form of a salt. Generally, silver (Ag) in the electrolyte 11 corresponds to impurities. When the concentration of silver (Ag) in the electrolyte 11 exceeds 50 mg/L, copper is electrodeposited unevenly on the rotating electrode drum 12. Therefore, the concentration of silver (Ag) in the electrolytic solution 11 is controlled to 50 mg/L or lower.

In order to control the concentration of silver (Ag) in the electrolyte 11 below 50 mg/L, by adding chlorine (Cl) to the electrolyte 11, the silver can be induced to precipitate in the form of silver chloride (AgCl) to remove silver (Ag). For example, the electrolyte 11 contains 10 mg/L to 30 mg/L of chlorine (Cl). Here, chlorine (Cl) includes chloride ions (Cl-) and chlorine atoms present in the molecule. Specifically, chlorine (Cl) may precipitate silver (Ag) ions in the form of silver chloride. Silver chloride can be removed by filtration.

In order to reduce the content of impurities in the electrolyte 11, the copper wire as a raw material of copper ions is heat-treated, the heat-treated copper wire is washed with an acid, and the acid-washed copper wire is added to sulfuric acid as an electrolyte.

The electrolyte 11 may have a flow rate of 35 m ³ /hr to 50 m ³ /hr. That is, in order to remove solid impurities present in the electrolyte 11 during the electroplating process, the electrolyte 11 may be circulated at a flow rate of 35 m ³ /hr to 50 m ³ /hr. During the circulation of the electrolyte 11, the electrolyte 11 may be filtered. This filtration can remove silver chloride (AgCl), so that the electrolyte 11 can be kept clean.

According to an embodiment of the present invention, the flow rate of the electrolyte 11 per unit time (second) changes, which is hereinafter referred to as "flow rate deviation", and can be controlled to 5% or less. When the flow velocity deviation exceeds 5%, an uneven copper layer 110 may be formed due to uneven plating, and the texture coefficient deviation of the (220) plane [TCB (220)] of the copper foil 100 exceeds 0.52.

Meanwhile, when the electrolyte 11 is treated with ozone, or the copper layer 110 is formed by electroplating, the clarity of the electrolyte 11 can be maintained or improved by adding peroxide and air to the electrolyte 11.

Then, the copper layer 110 is cleaned in the cleaning tank 20.

In order to remove impurities on the surface of the copper layer 110, the copper layer 110 is washed with water in the cleaning tank 20. Alternatively, in order to remove impurities on the surface of the copper layer 110, acid cleaning is performed first followed by water cleaning to remove the acid solution used for acid cleaning. The cleaning process can be omitted.

Then, a corrosion-resistant film 210 and a corrosion-resistant film 220 are formed on the copper layer 110.

Referring to FIG. 8, the copper layer 110 is immersed in the anti-corrosion liquid 31 contained in the anti-corrosion tank 30 to form the anti-corrosion film 210 and the anti-corrosion film 220 on the copper layer 110. Here, the anti-corrosion liquid 31 includes chromium, and chromium is chromium (Cr) existing in the form of ions in the anti-corrosion liquid 31. The anticorrosive liquid 31 may contain 0.5 g/L to 5 g/L of chromium. The anti-corrosion film 210 and the anti-corrosion film 220 thus formed are called "protective layers".

Meanwhile, the anti-corrosion film 210 and the anti-corrosion film 220 may include a silane compound treated with silane and a nitrogen compound treated with nitrogen.

The copper foil 200 is produced by forming these anti-corrosion films 210 and 220.

Then, the copper foil 200 is cleaned in the cleaning tank 40. This cleaning process can be omitted.

Then, a drying process is performed, and then the copper foil 200 is wound on a winder (WR).

Hereinafter, the present invention will be described in more detail with reference to Preparation Examples and Comparative Examples. The preparation examples are only for better understanding of the present invention and should not be construed as limiting the scope of the present invention.

Preparation Example 1-6 and Comparative Example 1-6

The copper foil is produced using a foil making machine including an electrolytic cell 10, a rotating electrode drum 12 provided in the electrolytic cell 10, and an electrode plate 13 spaced apart from the rotating electrode drum 12. The electrolyte 11 is a copper sulfate solution, the copper ion concentration of the electrolyte 11 is 75 g/L, the sulfuric acid concentration is 100 g/L, the chloride ion (Cl-) concentration is 17 mg/L, and the temperature of the electrolyte 11 is maintained at 55°C.

The electrolytic solution 11 includes 2-mercaptothiazoline (MTZ), bis-3-sulfopropyl disulfide (SPS), and polyethylene glycol (PEG) in the concentrations shown in Table 1. In addition, the electrolyte 11 is circulated at a flow rate of 42 m ³ /hr, and the flow rate deviation is shown in Table 1 above.

First, a current density of 60 ASD is applied between the rotating electrode drum 12 and the electrode plate 13 to form the copper layer 110.

Then, the copper layer 110 is immersed in the anti-corrosion liquid 31 contained in the anti-corrosion tank 30 to form an anti-corrosion film 210 and an anti-corrosion film 220 containing chromium on the surface of the copper layer 110. At this time, the temperature of the anti-corrosion liquid 31 is maintained at 30°C, and the anti-corrosion liquid 31 contains 2.2 g/L of chromium (Cr). As a result, the copper foils of Preparation Examples 1-6 and Comparative Examples 1-6 were prepared.

Table 1

The thus produced copper foils of Preparation Examples 1-6 and Comparative Examples 1-7 were measured for (i) (220) plane texture coefficient deviation [TCB (220)], (ii) tensile strength, (iii) copper Roughness profile element (Rsm) average width and maximum height roughness (Rmax) of the foil. The results are shown in Table 2.

(i) (220) Measurement of deviation of plane texture coefficient [TCB(220)]

First, the texture coefficient deviation [TCB (220)] of the (220) plane of the copper foils prepared in Preparation Examples 1-6 and Comparative Examples 1-6 was measured.

Specifically, the copper foils of Preparation Examples 1-6 and Comparative Examples 1-6 were prepared, by performing X-ray diffraction (X-ray diffraction) within a diffraction angle (2θ) of 30° to 95° [target : Interval of copper K α1, 2θ: 0.01°, and scan rate of 2θ: 3 degrees/min] Obtain an XRD pattern with peaks corresponding to n crystal planes, and obtain each crystal plane (hkl) from the XRD pattern XRD diffraction intensity [I(hkl)]. In addition, the diffraction intensity [I ₀ (hkl)] of n crystal planes of the standard copper powder specified by the Joint Committee on Powder Diffraction Standards (JCPDS) was obtained. In this case, the crystal planes are (111), (200), (220), and (311) planes, and n is 4.

Next, obtain the arithmetic mean value of "I(hkl)/I ₀ (hkl)" of n crystal planes, and then divide the (220) plane I(220)/I ₀ (220) by the arithmetic mean value To obtain the texture coefficient of the (220) plane [TC(220)]. That is, the texture coefficient [TC(220)] of the (220) plane will be calculated based on the following Equation 2:

[Equation 2]

Using the texture coefficient of the (220) plane [TC(220)], the deviation of the texture coefficient of the (220) plane [TCB(220)] is measured according to Equation 1 below.

Specifically, the texture coefficient deviation [TCB(220)] of the (220) plane is measured three times at various points on the left, center, and right in the width direction of the copper foil 100 (see Equation 1 below). Among them, the highest [TC(220)] value is TC _max , and the lowest [TC(220)] value is TC _min . The texture coefficient deviation [TCB(220)] is calculated from the difference between TC _max and TC _min , that is, the value of "TC _max -TC _min ".

[Equation 1] deviation of texture coefficient [TCB(220)] = TC _max -TC _min

(ii) Measurement of tensile strength

According to the specification of the IPC-TM-650 test method manual, the tensile strength of the copper foils prepared in Preparation Examples 1-6 and Comparative Examples 1-6 was measured using a universal testing machine. The width of the tensile strength measurement sample is 12.7 mm, the distance between the fixtures is 50 mm, and the measurement speed is 50 mm/min. The tensile strength of the sample was repeatedly measured three times, and the average value was evaluated as the measurement result.

(iii) Measurement of average width of roughness profile element (Rsm)

According to JIS B 0601-2001, the average width of the roughness profile element (Rsm) is measured using a roughness tester. Specifically, the average width of the roughness profile element can be measured using a SJ-310 type measuring instrument commercially available from Mitutoyo Corporation. At this time, the measurement length excluding the cut-off length is set to 4 mm, and the cut-off length is set to 0.8 mm at the beginning and later stages. In addition, the radius of the tip of the stylus is set to 2 μm.

Assuming that the distance from the point where a peak (valley) crosses the average line ML to the corresponding point of an adjacent peak (valley) is "XSi", the average width of the roughness profile element (Rsm) can be obtained by Equation 3 below.

[Equation 3]

(iv) Measurement of maximum height roughness (Rmax)

According to JIS B 0601-2001, the maximum height roughness (Rmax) is measured by a roughness tester. Specifically, the maximum height roughness (Rmax) is measured using an SJ-310 type measuring instrument commercially available from Mitutoyo Corporation. At this time, the measurement length excluding the cut-off length is set to 4 mm, and the cut-off length is set to 0.8 mm at the beginning and later stages. In addition, the radius of the tip of the stylus is set to 2 μm, and the measured pressure is 0.75 mN. After the setting as described above, based on the value measured with the Mitutoyo roughness tester, the measured value of the maximum height roughness (Rmax) is obtained.

(v) Observe the occurrence of bumps, wrinkles or tears

1) Preparation of anode

100 parts by weight of carbon as a commercially available anode active material was mixed with 2 parts by weight of styrene butadiene rubber (SBR) and 2 parts by weight of carboxymethyl cellulose (CMC), and distilled water was used as a solvent to prepare an anode active material slurry material. In Preparation Examples 1-6 and Comparative Examples 1-6, the anode active material slurry was coated with copper foil to a thickness of 40 μm using a doctor blade to make a copper foil with a width of 10 cm, dried at 120° C., and dried at 1 ton. /cm ² pressure to produce secondary battery anode.

2) Preparation of electrolyte

LiPF ₆ as a solute was dissolved at a concentration of 1 M in a non-aqueous organic solvent composed of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) mixed in a ratio of 1:2 to prepare an alkaline electrolyte. A 99.5 weight percent alkaline electrolyte was mixed with 0.5 weight percent succinic anhydride to prepare a non-aqueous electrolyte.

3) Preparation of cathode

Lithium manganese oxide (Li _1.1 Mn _1.85 Al _0.05 O ₄ ) and lithium manganese oxide (o-LiMnO ₂ ) having an orthogonal crystal structure were mixed in a weight ratio of 90:10 to prepare a cathode active material. The cathode active material, carbon black and poly(vinylidene fluoride) (PVDF) as a binder were mixed in a weight ratio of 85:10:5, and the resulting mixture was mixed with NMP as an organic solvent To prepare a slurry. Both surfaces of an aluminum foil with a thickness of 20 μm were coated with the slurry thus prepared and dried to produce a cathode.

4) Preparation of lithium secondary batteries for testing

The cathode and anode are provided in an aluminum can so that the cathode and anode are insulated from the aluminum can, and a non-aqueous electrolyte and a separator are provided to manufacture a coin-type lithium secondary battery. As a separator, polypropylene (Celgard 2325; thickness 25 μm, average pore diameter φ28 nm, porosity 40%) was used.

5) Observe the occurrence of bumps, wrinkles or tears.

In a series of processes for manufacturing lithium secondary batteries, it was observed whether tearing, wrinkling, or bulging of copper foil occurred. In particular, during the preparation of the copper foil and the anode, it is visually observed whether the copper foil is torn, wrinkled, or raised. A condition where no bumps, wrinkles or tears occur is called "good". The evaluation and observation results are shown in Table 2 below:

Table 2

In the process of manufacturing copper foil and preparing the lithium secondary battery of Comparative Examples 1-6, bulging, wrinkling, or tearing of the copper foil occurred. On the other hand, during the production of the copper foil and the lithium secondary battery in Preparation Examples 1-6, no bulging, wrinkling, or tearing of the copper foil occurred.

Specifically, in the subsequent process of manufacturing a lithium secondary battery using copper foil, bulging, wrinkling, or tearing of the copper foil occurs.

Comparative Example 1, in which the flow velocity deviation is higher than 5% and the (220) plane texture coefficient deviation [TCB (220)] is higher than 0.52 (wrinkles occur).

Comparative Example 2, in which the concentration of 2-mercaptothiazoline is less than 1 mg/L and the tensile strength is less than 29 kgf/mm ² (wrinkles occur).

Comparative Example 3, in which the content of mercaptothiazoline (MTZ) in the electrolyte is higher than 20 mg/L and the tensile strength is higher than 65 kgf/mm ² (tearing occurs).

Comparative Example 4, in which the content of bis-3-sulfopropyl disulfide (SPS) in the electrolyte is less than 2 mg/L and the average width of the roughness profile element (Rsm) is less than 18 μm (tearing occurs).

Comparative Example 5, in which the content of bis-3-sulfopropyl disulfide (SPS) in the electrolyte is higher than 21 mg/L and the average width of the roughness profile element (Rsm) is less than 148 μm (wrinkles occur).

Comparative Example 6, in which the content of polyethylene glycol (PEG) in the electrolyte is less than 50 mg/L and the maximum height roughness (Rmax) is less than 0.6 μm (bulge occurs).

The copper foils according to Comparative Examples 1 to 6 are not suitable for the anode current collector of lithium secondary batteries.

On the other hand, in the preparation examples 1 to 6 prepared under the conditions according to the examples of the present invention, in the process of manufacturing the copper foil or in the process of manufacturing the lithium secondary battery using the copper foil, the bulging of the copper foil, Torn and wrinkled. Therefore, the copper foil according to the embodiment of the present invention has excellent roll-to-roll (RTR) workability and is suitable for an anode current collector of a lithium secondary battery.

The copper foil according to the embodiment of the present invention is highly resistant to bumps, wrinkles, or tears. Therefore, according to the embodiments of the present invention, during the manufacturing of the copper foil or during the manufacturing of the secondary battery using the copper foil, the occurrence of ridges, wrinkles, or tears is prevented. The copper foil according to the embodiment of the present invention has excellent roll-to-roll (RTR) workability.

In addition, according to another embodiment of the present invention, the copper foil is prevented from being raised, wrinkled, or torn, or an electrode for a secondary battery can be manufactured.

It is obvious to those skilled in the art that the above-mentioned present invention is not limited to the above-mentioned embodiments and drawings. Moreover, various substitutions, modifications, and changes can be made in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention is defined by the scope of the attached patent application, and it is intended that all changes and modifications derived from the meaning, scope, and equivalent concepts of the scope of the patent application fall within the scope of the present invention.

10‧‧‧Electrolyzer 11‧‧‧Electrolyte 12‧‧‧ Rotating electrode roller 13‧‧‧Electrode plate 20‧‧‧Cleaning tank 30‧‧‧Antiseptic tank 31‧‧‧Antiseptic liquid 40‧‧‧Cleaning tank 100 ‧‧‧Copper foil 110‧‧‧Copper layer 200‧‧‧Copper foil 210‧‧‧Anticorrosive film 220‧‧‧Anticorrosive film 300‧‧‧Electrode 310‧‧‧Active material layer 320‧‧‧‧Active material layer 340‧ ‧‧Anode 341‧‧‧Anode current collector 342‧‧‧Active material layer 350‧‧‧Electrolyte 360‧‧‧Isolation membrane 370‧‧‧Cathode 371‧‧‧Cathode current collector 372‧‧‧Cathode active material layer 400 ‧‧‧Electrode 410‧‧‧polymer film 500‧‧‧secondary battery 600‧‧‧flexible copper foil laminated film

FIG. 1 is a schematic cross-sectional view showing a copper foil according to an embodiment of the present invention. FIG. 2A shows an example of the XRD pattern of copper foil. FIG. 2B is a graph showing roughness contour elements. 3 is a schematic cross-sectional view showing a copper foil according to another embodiment of the present invention. 4 is a schematic cross-sectional view showing an electrode for a secondary battery according to another embodiment of the present invention. 5 is a schematic cross-sectional view showing an electrode for a secondary battery according to another embodiment of the present invention. 6 is a schematic cross-sectional view showing a secondary battery according to another embodiment of the present invention. 7 is a cross-sectional view showing a flexible copper foil laminate film according to another embodiment of the present invention. 8 is a schematic diagram illustrating the method of manufacturing the copper foil shown in FIG. 3. Fig. 9 is an image showing that bumps appear in the copper foil. FIG. 10 is an image showing wrinkles in copper foil.

100‧‧‧Copper foil

110‧‧‧copper layer

210‧‧‧Anti-corrosion film

Claims (13)

One kind of copper foil comprising a copper layer and having 29kgf / mm ² to 65kgf / mm ² in a tensile strength, an average width of a roughness profile of the element 18 to 148μm (Rsm) of 0.52 or less and a Texture coefficient deviation [TCB(220)]. The copper foil as described in claim 1, further comprising an anti-corrosion film disposed on the copper layer. The copper foil according to claim 2, wherein the anticorrosive film contains at least one of chromium (Cr), a silane compound, or a nitrogen compound. The copper foil according to claim 1, wherein the copper foil has a maximum height roughness (Rmax) of 0.6 μm or more. The copper foil according to claim 1, wherein the copper foil has a weight deviation of 5% or less. The copper foil according to claim 1, wherein the copper foil has an elongation of 2% or more at room temperature of 25±15°C. The copper foil according to claim 1, wherein a thickness of the copper foil is 4 μm to 30 μm. A secondary battery electrode, comprising: the copper foil according to any one of claims 1 to 7; and an active material layer provided on the copper foil. A secondary battery includes: a cathode; an anode facing the cathode; an electrolyte to provide an environment in which ions can move between the cathode and the anode; and a separator to electrically Insulating the cathode and the anode, wherein the anode comprises: the copper foil as described in any one of claims 1 to 7; and an active material layer provided on the copper foil. A flexible copper foil laminated film, comprising: a polymer film; and the copper foil according to any one of claims 1 to 7 is provided on the polymer film. A method of manufacturing a copper foil, the method comprising: providing a current density of 30A / dm ² to 80A / dm ² in an electrolytic solution between the copper ions contained in a spaced-apart electrode plates and a rotating drum electrode To form a copper layer; wherein, the electrolyte contains: 70g/L to 100g/L copper ions; 80g/L to 130g/L sulfuric acid; 2mg/L to 20mg/L 2-mercaptothiazoline (2-mercaptothiazoline ); 2 mg/L to 20 mg/L of bis-(3-sulfopropyl) disulfide (SPS); and 50 mg/L or less polyethylene glycol (PEG) . The method according to claim 11, wherein the electrolytic solution contains 10 mg/L to 30 mg/L of chlorine (Cl). The method according to claim 11, wherein the flow rate deviation of the electrolyte per unit time (second) is 5% or less.

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