First you need to gather up all of the materials you will need. Below is a list of the following items needed to conduct this project:
- 2 wires with stripped off ends
- Aluminum foil
- A bowl
- Warm water
- 6 copper pennies
- Paper towels
- A paper plate
- A light bulb – 1.5 volt
Are you ready? Let’s get started. Dissolve 1 tablespoon of salt in 1 cup of warm (not hot) water in a bowl. Make sure that there is some salt left undissolved in the bottom of the bowl. Next place a penny on a piece of aluminum foil and draw around it. Do the same thing using paper towel instead of the foil. Repeat these steps 5 times. Cut all the circles out that you made on the foil and the paper towel. When you’re done, you should have 6 foil circles and 6 paper towel circles. Tape the end of one wire to a foil circle while dipping a paper towel circle into your bowl of warm salt water. Put the foil circle that you taped the wire to on your paper plate and put the paper towel circle that you submerged in the water on top of that. Next put a penny on top of the wet paper towel circle. You will repeat these steps using all of your pennies, foil circles and wet paper towel circles. Then tape the other wire to the last coin on top (see the diagram for help). Congratulations! You’ve just made a battery!
To test your battery, attach the end of one of the wires to the metal bottom of the light bulb. Wrap the end of the other wire around the metal shaft of the light bulb. The bulb should light up.
So why/how did the bulb light up? There are metal atoms in the aluminum foil that will dissolve in the warm salt water (the electrolyte of the battery). When this happens, there are electrons that are left behind. Electricity is created when those electrons flow through the wet foil and paper circles (the circuit). The metals will eventually dissolve completely in the warm salt water and no more electrons will be formed. When this happens the battery stops working.