Abstract: An electrochemical cell (10) having a structural organization that permits it to operate as either a galvanic or polarographic cell. The structural organization includes an electrolyte reservoir (E) comprised of a solid-like material such as a gel to releasably hold a liquid electrolyte therein. The cathode electrode (K) is defined to be surrounded by a porous material (16) to convey the electrolyte to the cathode electrode (K) to provide the necessary wetting action with the evaporation through the liquid impermeable, gas permeable membrane (M) for the cell (10). The electrolyte reservoir is spaced below the membrane (M) and is solely conveyed by capillary action to the cathode electrode. A venting element (V) is defined for the cell container (11) to prevent internal pressure variations while preventing loss of electrolyte therethrough.