Electrolytic copper foil, method for manufacturing the same, and anode for lithium secondary battery of high capacity

An anode for a Lithium (Li) secondary battery, the anode comprising:

• a current collector including an electrolytic copper foil having a first surface and a second surface opposite to the first surface;
• and
• an anode active material layer on the second surface,
• wherein the electrolytic copper foil comprises:
• a first protective layer forming the first surface;
• a second protective layer forming the second surface, the second protective layer being in contact with the anode active material layer at the second surface;
• and
• a copper film between the first and second protective layers,
• wherein an oxygen-containing part at the second surface has a thickness (OT) of not less than 1.5 nanometers (nm) and less than 8.0 nm,
• the thickness of the oxygen-containing part at the second surface is a Silicon Dioxide (SiO2) conversion thickness of a portion of the second protective layer,
• the electrolytic copper foil is heat treated at 110° C. for 10 minutes to have a breaking strength of 25 to 57 kilograms of force per square millimeter (kgf/mm2), and
• the portion of the second protective layer is a portion showing a concentration of oxygen component of not less than 10 atom % when measured with Auger Electron Spectroscopy (AES) from the second surface, wherein the concentration of the oxygen component measured from the second surface increases from the second surface to a first depth from the second surface.