| abstract |
This negative electrode foil for a solid electrolyte capacitor: increases capacitance, reduces ESR and leakage current, improves heat resistance, and reduces manufacturing costs; and improves the power density, achieves rapid charging/discharging, and improves the lifespan characteristics of energy storage elements such as rechargeable batteries, electric double-layer capacitors, and hybrid capacitors. The negative electrode foil or a current collector is used, which: is obtained by forming a metal layer, a mixed layer obtained by mixing a material constituting the metal layer with carbon, and a carbon layer substantially comprising carbon, on a metal foil; and is configured in such a manner as to change as the components of the mixed layer change from a component containing only the material substantially constituting the metal layer to a component substantially containing only carbon, and from the metal layer to the carbon layer. |