Abstract: A double layer capacitor includes first and second electrode structures separated by a porous separator. The first and second electrode structures each include a current collector foil, a primary coating formed on the current collector foil, and a secondary coating formed on the primary coating. The primary coatings include conducting carbon powder, and the secondary coatings include activated carbon powder. A method of making the electrode structures includes the steps of: preparing a first slurry that includes conducting carbon powder and a binder; applying the first slurry to a current collector plate; drying the applied first slurry to form a primary coating; preparing a second slurry that includes activated carbon powder, a solvent and a binder; and applying the second slurry to the primary coating.