An electrochemical element or cell and a cathode for same which contains an anode, a separator, and a cathode composed of manganese dioxide; this cathode incorporates an inorganic crystalline additive of tungsten oxide, compounds of zirconium, titanium oxide with rutile structure, yttrium oxide, cerium oxide, zeolites and aluminosilicates, and at least one of these is present in a proportion or range between one ten thousandth (0.0001) and ten (10) percent by weight of the cathode mass.