Electrolytic copper foil, electrode comprising the same, secondary battery comprising the same, and method for manufacturing the same

An electrolytic copper foil having a first surface and a second surface opposite to the first surface, the electrolytic copper foil comprising:

• a first protective layer at the first surface;
• a second protective layer at the second surface;
• and
• a copper film between the first and second protective layers,
• wherein the electrolytic copper foil has a longitudinal rising of 30 mm or less and a transverse rising of 25 mm or less,
• the transverse rising is 8.5 times the longitudinal rising or less, and
• the longitudinal rising and transverse rising are, when a center portion of the electrolytic copper foil is cut along a X-shaped cutting line of 5 cm×5 cm in a first direction which makes an angle of 35° to 55° with a longitudinal direction parallel with a transferring mark formed on the electrolytic copper foil and in a second direction perpendicular to the first direction so that a pair of first segments arranged side by side along the longitudinal direction and a pair of second segments arranged side by side along a transverse direction perpendicular to the longitudinal direction are formed, the greater of risings of the first segments in a direction the first or second surface is facing and the greater of risings of the second segments in a direction the first or second surface is facing, respectively.