How to Build a Battery?

To build a homemade battery all you need is 10 copper pennies, aluminum foil, paper towel, scissors, electrical tape, salt water, and wires. First you prepare the anode by cutting 10 circles in the aluminum foil the size of the pennies. Then cut the paper towels in squares as wide as the pennies. Then stack, foil, paper, penny. Soak each stack in salt water. Finally connect the wires to it. Look here for more information: