Lithium ion secondary battery, current collector constituting the negative electrode of the secondary battery, and electrolytic copper foil constituting the negative electrode current collector

摘要

Double-sided shape with good wettability with the active material slurry, high battery capacity, little battery capacity deterioration even after repeated charge / discharge cycles, and the active material coating layer is difficult to peel off from the copper foil as the negative electrode current collector Provides an electrolytic copper foil of the same level, and a lithium secondary battery using the electrolytic copper foil as a current collector. An electrolytic copper foil for a negative electrode current collector of a lithium ion secondary battery, wherein both surfaces of the electrolytic copper foil are electrolytic deposition surfaces, and the deposition surfaces are columnar crystal structures. A negative electrode for a lithium secondary battery using the electrolytic copper foil as a current collector. A lithium secondary battery incorporating the negative electrode. The first surface of the electrolytic copper foil is a surface formed by copper electrodeposition of a columnar crystal structure on the drum surface, and the second surface opposite to the first surface is formed after the first surface foil formation, It is a surface formed by copper electrodeposition of a columnar crystal structure on the back side of one surface.