A photolithographic method, to produce micro-protrusions which are uniform in height on a porous substrate to maintain space separation between electrodes in an electrical storage device, comprises: (a) obtaining an unexposed photoresist film which is essentially inert to subsequent electrolyte conditions and is electrically insulating when cured; (b) obtaining a thin electrode material comprising a thin flat electrically conducting metal sheet coated on one or both flat sides with electrically conducting porous metal oxide or electrically conducting carbon; (c) applying the photoresist film to one or to both flat sides of the electrode material; (d) placing a mask having a number of small holes over the photoresist; (e) exposing the photoresist to a light source of an intensity and for a time effective to substantially cure the light exposed photoresist material through the holes in the mask such that the photoresist material through the holes are exposed to a uniform amount of light to create substantially cured micro-protrusions of uniform height followed by removing the mask; (f) developing the photoresist film to leave the substantially cured micro-protrusions on the surface of the electrode material and to remove unreacted film; and (g) further curing the remaining exposed substantially cured micro-protrusions where the micro-protrusions of uniform height essentially retain their shape and dimensions.    USE -   The electrical storage device having the micro-protrusions is a battery or capacitor (claimed). The capacitor is used in defibrillators, pacemakers, electric vehicles, portable telephones, etc.    ADVANTAGE -   The method produces a reliable small space separation between electrodes in electrical storage devices with a large open cross-sectional area. Efficient packaging of the devices is provided by reducing the gap between the anode and cathode and reducing the electrical resistance of the ionically conducting electrolyte by providing large open cross-sectional areas of 95-98%.