ELECTROLYTIC COPPER FOIL HAVING OPTIMUM PEAK ROUGHNESS, ELECTRODE COMPRISING THE SAME, SECONDARY BATTERY COMPRISING THE SAME, AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an electrolytic copper foil having a peak roughness (Rp) optimized for enhancing capacity retention of a secondary battery, an electrode comprising the same, a secondary battery comprising the same, and a method for producing the same.SOLUTION: An electrolytic foil 110 is provided which comprises a first surface and a second surface opposite to the first surface. The first surface and the second surface each have a peak roughness (Rp) of 0.36 to 1.69 μm, in which the difference between a peak roughness (Rp) on the first surface and a peak roughness (Rp) on the second surface is 0.6 μm or less. In the electrolytic foil 110, the first surface has a first protecting layer 112a, and the second surface has a second protecting layer 112b; the protecting layers 112a, 112b each have Cr; its adhesion amounts range from 0.5 to 5.5 mg/m; and its difference is 2.5 mg/mor less. The electrolytic foil 110 has a thickness of 4 to 20 μm and a yield strength of 21 to 58 kgf/mmat room temperature of 25±15°C.SELECTED DRAWING: Figure 1