Volta made his "Voltaic Pile" battery with units consisting of saltwater-soaked paper sandwiched between a silver disk and a zinc disk. He stacked up this basic unit to create a battery with significant voltage. We now call such basic units cells. You can make a similar battery quite easily with household items. You will need five pennies made after 1982, cardstock or paperboard, salt, water, electrical tape, 120-grit sandpaper and two wires with stripped ends. Pennies made in 1983 and after are copper-coated zinc disks. Thanks to this f
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