The present invention relates to an electrolytic copper foil for a secondary battery, and a method of producing the same. The electrolytic copper foil for a secondary battery exhibits a little change in a physical property caused by a difference in a crosshead speed when tensile strength and an elongation percentage of the electrolytic copper foil are measured, thereby achieving excellent charging and discharging characteristics of a battery and preventing exfoliation of an active material. The electrolytic copper foil for a secondary battery is produced from a plating solution containing Total Organic Carbon (TOC), cobalt, and iron by using a drum, in which a ratio of the TOC to the cobalt and the iron contained in the electrolytic copper foil follows Formula 1 below.
TOC/(cobalt+iron)=1.3 to 1.5  [Formula 1]

A method for preparing an electrolytic copper foil includes placing an anode and a cathode to be plated in a twin crystal growth agent containing electroplating solution in an electroplating tank, and, under conditions that the electroplating solution is provided with randomly alternating transitions of one or two of an ultrasonic wave at a frequency f11 and an ultrasonic wave at a frequency f12 and one or two of an ultrasonic wave at a frequency f21 and an ultrasonic wave at a frequency f22, performing direct current electroplating to obtain the electrolytic copper foil, wherein f11>40 kHz, 15 kHz<f12≤40 kHz, 0 kHz<f21≤15 kHz, and f22=0 kHz.

A method for preparing an electrolytic copper foil includes placing an anode and a cathode to be plated in a twin crystal growth agent containing electroplating solution in an electroplating tank, and, under conditions that the electroplating solution is provided with randomly alternating transitions of one or two of an ultrasonic wave at a frequency f11 and an ultrasonic wave at a frequency f12 and one or two of an ultrasonic wave at a frequency f21 and an ultrasonic wave at a frequency f22, performing direct current electroplating to obtain the electrolytic copper foil, wherein f11>40 kHz, 15 kHz<f12≤40 kHz, 0 kHz<f21≤15 kHz, and f22=0 kHz.

The present invention relates to an electrolytic copper foil for a secondary battery, having excellent physical properties at a low temperature, and a method for producing the electrolytic copper foil. The electrolytic copper foil for a secondary battery shows little change in the physical properties, such as tensile strength and elongation, of a copper foil even at a low temperature and thereby exhibits excellent cycle properties at the low temperature. The electrolytic copper foil for a secondary battery is produced from a plating solution, containing total organic carbon (TOC), cobalt, iron and zinc, by using a drum and coated with a negative electrode active material, wherein the ratio between the TOC, cobalt, iron and zinc contained in the electrolytic copper foil follows the following formula 1:
TOC/(cobalt+iron+zinc)=1.0-1.2.  [Formula 1]

The present invention relates to an electrolytic copper foil for a secondary battery, having excellent physical properties at a low temperature, and a method for producing the electrolytic copper foil. The electrolytic copper foil for a secondary battery shows little change in the physical properties, such as tensile strength and elongation, of a copper foil even at a low temperature and thereby exhibits excellent cycle properties at the low temperature. The electrolytic copper foil for a secondary battery is produced from a plating solution, containing total organic carbon (TOC), cobalt, iron and zinc, by using a drum and coated with a negative electrode active material, wherein the ratio between the TOC, cobalt, iron and zinc contained in the electrolytic copper foil follows the following formula 1:
TOC/(cobalt+iron+zinc)=1.0-1.2.  [Formula 1]

The carrier-foil-attached ultra-thin copper foil according to one embodiment of the present invention comprises a carrier foil, a release layer, a first ultra-thin copper foil, an Al layer, and a second ultra-thin copper foil, wherein the release layer may comprise a first metal (A1) having peeling properties, and a second metal (B1) and third metal (C1) facilitating the plating of the first metal (A1).

The present invention relates to a method for producing an electrolytic copper foil, the method enabling providing an electrolytic copper foil such that the electrical conductivity is 99% or more, the thickness is 10 μm or less, a problem of a bend is suppressed, the front side and the rear side are flat, the tensile strength is 500 MPa or more, and the elongation percentage is 5.5% or more. The method for producing an electrolytic copper foil includes forming an electrolytic copper foil by using, as an electrolytic solution, a sulfuric acid-copper sulfate aqueous solution not containing a heavy metal other than a copper metal, using an insoluble anode and a cathode drum facing the insoluble anode, and passing a direct current between these electrodes, wherein, in the electrolytic solution, particular additives (A) to (E) are contained each in a particular amount, and the additive (D) and the additive (A) are each added in a ratio such that (D)/(A) is 0.2 to 0.7.

The present invention relates to an electrolytic copper foil for a secondary battery, and a method of producing the same. The electrolytic copper foil for a secondary battery exhibits a little change in a physical property caused by a difference in a crosshead speed when tensile strength and an elongation percentage of the electrolytic copper foil are measured, thereby achieving excellent charging and discharging characteristics of a battery and preventing exfoliation of an active material. The electrolytic copper foil for a secondary battery is produced from a plating solution containing Total Organic Carbon (TOC), cobalt, and iron by using a drum, in which a ratio of the TOC to the cobalt and the iron contained in the electrolytic copper foil follows Formula 1 below.
TOC/(cobalt+iron)=1.3 to 1.5  [Formula 1]

The present invention relates to an electrolytic copper foil for a secondary battery, and a method of producing the same. The electrolytic copper foil for a secondary battery exhibits a little change in a physical property caused by a difference in a crosshead speed when tensile strength and an elongation percentage of the electrolytic copper foil are measured, thereby achieving excellent charging and discharging characteristics of a battery and preventing exfoliation of an active material. The electrolytic copper foil for a secondary battery is produced from a plating solution containing Total Organic Carbon (TOC), cobalt, and iron by using a drum, in which a ratio of the TOC to the cobalt and the iron contained in the electrolytic copper foil follows Formula 1 below.
TOC/(cobalt+iron)=1.3 to 1.5  [Formula 1]

A method for producing an electrolytic copper foil is provided. The method includes preparing a copper electrolytic solution including at least one addition agent and performing an electroplating step including: electrolyzing the copper electrolytic solution to form a raw foil layer. The raw foil layer has a first surface and a second surface opposite to the first surface. In the X-ray diffraction spectrum of the first surface, a ratio of the diffraction peak intensity I(200) of the (200) crystal face of the first surface relative to the diffraction peak intensity I(111) of the (111) crystal face of the first surface is between 0.5 and 2.0. A ratio of the diffraction peak intensity I(200) of the (200) crystal face of the second surface relative to the diffraction peak intensity I(111) of the (111) crystal face of the second surface is between 0.5 and 2.0.