Alessandro Volta was a physicist born in Como, Italy, who invented the battery around 1800. His first working battery was considered a wet battery because he used saltwater soaked cardboard between pieces of zinc and copper. The wet battery was named voltaic pile and has been refined since that day to yield modern batteries. Volta's invention caught the attention of Napoleon, who bestowed Volta with the honorable "count" title.
Teach children about stored energy and discuss the most common form: batteries. Explain that a chemical reaction takes place inside the battery when the positive end and the negative end are connected by a wire. Showing children how to light a light bulb using a battery and wire gives them a physical representation of how electricity works and its everyday presence. Clarifying safety tips, such as avoiding water, touching exposed wires and keeping the battery intact, reduces accidental electrical shocks and acid burns.
A simple power source lights a 3-volt flashlight bulb. Create a power source by securing two D batteries together by wrapping electrical tape around the centers with opposing ends together. Use small strips of electrical tape to hold a paper clip with ends that touch both the positive and negative plates on one side of the banded batteries. Insulated No. 22 copper wires with stripped ends attached to the open ends of each battery act as the conductor while protecting you from handling the live wire. Touching the two ends to a light bulb yields light but prevents the two wires from touching each other to eliminate electrical shorts.
Help the child create three simple circuits using the battery packs as the power sources and 3-volt flashlight bulbs for the light. Attach the light bulbs in a single row on a piece of wood and nail a wood clothespin near each bulb to hold the wires in place when a closed circuit is formed to light the bulbs. Remind the child to grasp the wire's coated portion. Construct a cardboard traffic light with three holes at the level of each bulb and cover the holes with red, yellow and green cellophane. Spray painting the cardboard black and adding light covers adds realistic effects.