Composite electrodes are constructed with pressure-bonding techniques
instead of an adhesive. A current collector is made from aluminum foil
roughed on both surfaces. The surfaces of the collector can be treated to
enhance adhesion to the surfaces. Layers of film that includes active
electrode material, such as activated carbon, are fabricated and
pressure-bonded to the current collector using a calender with heated
rollers. The resulting composite sheet is then processed to shape
electrodes, which can be used in electrical energy storage devices,
including double layer capacitors.