A battery has a positive and negative side to it. The positive side is called the cathode , and the negative side is called the anode . To show how a battery works I will attach it to a light bulb. As the light bulb draws power from the battery, electrons start to flow from the anode through the external bulb connection and back to the cathode. This flow of energy from the battery to power the light results in a decrease in the energy level of the battery.
The battery acts on all of our lives. We all use the battery at least once a day, but always more. The battery is used to drive our cars and talk on our phones, so everyone uses it!
You can use coins and paper towels. Mix salt with water (as much salt as the water will hold) and soak the paper towel in this brine. Then create a pile by alternating pennies and nickels. See what kind of voltage and current the pile produces. Try a different number of layers and see what effect it has on voltage. Then try alternating pennies and dimes and see what happens. Also try dimes and nickels. Other metals to try include aluminum foil and steel. Each metallic combination should produce a slightly different voltage.