Patent ID: 8097365

Claim:
A battery electrode comprising: an electrode current collector, the electrode current collector including an electrolytic copper foil, wherein, said front and rear surfaces of said electrolytic copper foil are roughened by copper or copper alloy particles affixed thereto, the electrode current collector has a front surface color and a back surface color, at least one of the front surface color and the back surface is a color belonging to a spherical color space, the color space being represented by: 50 ≦L*≦ 80, 5 ≦a*< 60, 5 ≦b*< 60, where L*, a*, and b* are numeric values in which L* represents a position along a z-axis corresponding to brightness, a* represents a position along a circumferential direction corresponding to hue, and b* represents a position along a radial direction corresponding to chroma, and the front surface color and the back surface color are different from each other in such a way that at least one of the L*, a*, and b* numeric values of the front surface color is different from at least one of the L*, a*, and b* numeric values of the back surface color.