Abstract: Provided are electrochemical (e.g., double layer capacitor) cell designs, and methods of their manufacture, which reduce both cell size and impedance while maintaining inter-electrode dielectric integrity and cell performance and facilitating manufacturing. The designs adapt mircofabrication techniques from the field of semiconductor fabrication in order to form and pattern thin dielectric films on electrodes. Existing microfabrication techniques allow for the formation of dielectric (e.g., polyimide) films having a thickness of about 1 to 2 microns. Dielectric films formed on electrodes may be patterned according to well known procedures in the semiconductor fabrication field to provide area for unimpeded ion exchange between the electrodes. The patterning may produce contiguous or noncontiguous dielectric layers between the electrodes having porosity of about 30 to 80%, preferably about 60 to 80% while dielectric integrity is maintained.

Abstract: Provided are electrochemical (e.g., double layer capacitor) cell designs and methods of their manufacture, which reduce cell impedance and increase volumetric capacitance while maintaining inter-electrode dielectric integrity and cell performance. The designs eliminate the contiguous separator material used as the dielectric between the electrodes in conventional double layer capacitor cells. The separator is replaced by a noncontiguous array of dielectric particles, such as glass beads or fibers, sized and distributed to provide substantially uniform separation between the electrodes. The remaining space between the electrodes unoccupied by the dielectric particles is filled with electrolyte. In this way, a much greater proportion of the dielectric space between the electrodes is available for ionic transport. Glass beads and fibers are available with diameters less than that available for currently-used separator materials.