NOVELTY - An electrochemical cell comprises a composite current collector having a density of 0.1-10 g/cm3. The collector contains a metallic layer on a polymer substrate. The metallic layer is an alloy of at least two metals; or at least one metal selected from zinc, cadmium, mercury, gallium, indium, thallium, tin, lead, arsenic, antimony, bismuth and selenium. The metallic layer has a thickness of 1-5000 microns.    USE - As electrochemical cell including sealed lead-acid cell or battery; sealed galvanic cell; cylindrical cell (claimed), electrosynthesis, electroplating cells, fuel cells, primary/rechargeable cells.    ADVANTAGE - The electrochemical cell, after 6 years of storage at room temperature and/or 4 weeks at 65 degrees C, has a pass rate with respect to leakage/frosting of over 85% with respect to leakage/frosting and has a discharge capacity retention of more than 10%. The electrochemical cell, after 6 years of storage at room temperature, has a discharge capacity retention of more than 10%. The composite current collector limits the short circuit current of the cell, when expressed in Amperes to a value of 50-100% of the value of the zinc amount expressed in grams. The electrochemical cell minimizes the generation of hydrogen in the cell while providing a high rate cell with high discharge capacity, high specific power density and high specific energy density as well as long shelf life, which can be manufactured economically in large volume. The current collector has composite that is inexpensive, lightweight, and conductive. The electrochemical cell for use in negative electrodes of aqueous electrolyte galvanic cells thus enhancing electrical performance including discharge capacity, specific power, specific energy and applicable cycle life), while minimizing hydrogen gassing and providing exceptionally long shelf lives.    DETAILED DESCRIPTION - An electrochemical cell comprises a composite current collector having a density of 0.1-10 g/cm3. The collector contains a metallic layer on a polymer substrate. The metallic layer is an alloy of at least two metals; or at least one metal selected from zinc (Zn), cadmium (Cd), mercury (Hg), gallium (Ga), indium (In), thallium (Tl), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi) and selenium (Se). The metallic layer has a thickness of 1-5000 microns. The polymer substrate contains filler materials (0-75 vol.% or wt.%). The electrochemical cell is a sealed galvanic cell comprising a zinc negative electrode, which is free of Hg, Cd and Pb. The zinc negative electrode comprises the composite current collector. The composite current collector has a density of 0.1-3 g/cm3, and the voltage drop across the entire height of the composite current collector at an applied current of 1 Ampere is of 1-250 mV. The polymer substrate surface is rendered conductive by applying a conductive paint containing at least one metal; a metal alloy; or at least one compound, selected from Zn, Cd, Hg, Ga, In, Tl, Sn, Pb, As, Sb, Bi and Se. The metallic coating is built up to its desired thickness by electrodeposition, electroless deposition, electrophoretic deposition, physical vapor deposition (PVD), chemical vapor (CVD), sputtering, cold or hot spraying of powders or melts or metallic coating is attached to the substrate using an adhesive. The metallic layer has a tapered thickness profile having the highest thickness in the vicinity of the post. The composite current collector has the shape of a nail, tube, foil, plate, woven mesh, expanded mesh or more complex shape selected from spiral, blade, formed or bent foil or tube, book mold type grid, radial grid, expanded grid, punched foil, perforated foils and open cell foam. The composite current collector is suitably perforated or hollowed to provide space for gas expansion, additional electrolyte, active electrode material or gas recombination device or devices. The cell contains a positive electrode; a hydrogen recombination catalyst; an active electrode material including composite conductive particles selected from flakes, needles or platelets.