ELECTRODE FOIL AND ELECTRONIC DEVICE

An electrode foil functioning as both a supporting substrate and an electrode and suitable for low-cost high-efficiency production of flexible electronic devices having functionality on their both sides is provided. An electrode foil of the present invention comprises a metal foil, wherein the metal foil has a thickness of 1 to 250 µm, and wherein the outermost surfaces on both sides of the electrode foil are ultra-smooth surfaces each having an arithmetic mean roughness Ra of 30.0 nm or less as determined in accordance with JIS B 0601-2001.