TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The divalent cation is chosen from bivalent zinc cation, bivalent calcium cation, bivalent magnesium cation, bivalent iron cation or their mixture, preferably bivalent zinc cation. The aqueous electrolyte further comprises sulfonate anion, aldehyde anion, nitrate anion, chloride anion, bromide anion, chlorate anion, and/or CO2CH3-. The electrolyte has pH that is approximately neutral, preferably 3-6. The layered material comprises a metal oxide, a mixed metal oxide, a metal sulfide, a zinc metal phosphate, a zinc metal oxide, or their mixture, preferably manganese oxide, vanadium oxide, manganese vanadium oxide, titanium sulfide, tungsten oxy chloride, or their mixture, more preferably manganese oxide which undergoes a reduction in its oxidation state of 1 or more during discharge of the electrochemical cell. The cathode material comprises manganese oxide having compositional formula: MnxOy or manganese vanadium oxide of formula: MnxVzOy.x,z=1 or more;andy=2 or more.The manganese oxide is of formula: MnO2, Mn5O8, Mn3O7.3H2O, Mn7O14.3H2O, Mn4O9.3H2o, Mn2O4, Mn4O18.H2O, or their mixture, preferably Mn5O8. The manganese oxide has predominant crystal structure of alpha -MnO2, beta -MnO2, gamma -MnO2, delta -MnO2, layered, or their mixture. The mean particle diameter of manganese oxide (Mn5O8) is 50 mu m or less. The cathode further comprises 15 wt.% or less carbon powder and an additive which stabilizes the crystal lattice structure of manganese oxide. The carbon powder comprises acetylene black, furnace black, channel black, graphite, activated carbon, graphene, or their mixture. The additive comprises titanium sulfide, titanium boride, bismuth oxide, or their mixture. The concentration of additive is 20 wt.% or less. The cathode is doped with aluminum, boron or their mixture. The anode comprises a metal. A portion of the metal is transformed into a divalent cation when the cell is discharged. The metal comprises zinc, magnesium, or their mixture. The cathode and/or anode further comprise 3-15 wt.% binder and a current collector. The current collector comprises one or more electroconductive metals or an electroconductive polymer material. The current collector comprises a woven material, a nonwoven material, or their mixture, preferably a sheet of nonwoven material which optionally comprises one or more perforations. Preferred Method: Zinc sulfate, zinc nitrate, zinc carbide, zinc chlorate, zinc bromide, and/or zinc complex (Zn(CHO2)2,Zn(CO2CH3)2), are further dissolved in water to generate zinc divalent cation.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: The binder comprises polyacrylonitrile, polyvinyl alcohol, polyvinyl chloride, polyethylene oxide, polytetrafluoroethylene, polyvinylidene difluoride, polymethylmethacrylate, or their mixture.