Featured Activity: Build a Battery

Scientists are often just people who are curious and creative. Alessandro Volta was this sort of person. He believed that he could use chemistry to create electricity. At first, no one believed him, but after many experiments, mistakes, and ideas that didn’t work, he used a pile of metallic disks separated by salty cloth to generate electricity!

This Build a Battery activity will give you a chance to try out his idea which is now called a voltaic pile pr voltaic battery, named for Alessandro Volta who wouldn’t give up on his idea no matter how many times he failed. The unit of electrical energy, the volt, is also named after him. The activity will guide youth through creating a battery that converts chemical energy to electrical energy. The supplies you will need are:

  • wire,
  • tape,
  • pennies,
  • aluminum foil,
  • saltwater,
  • paper towels,
  • a set of headphones for each small group (to hear the electricity), and
  • a few store-bought batteries for comparison.

As you conduct the experiment, youth will soak paper towels in saltwater and stack wet paper towels, a penny, and aluminum foil. Aluminum has a tendency to lose its electrons, copper tends to gain electrons and the saltwater causes the chemical reaction. The freed electrons flow through the wire, through the headset (which youth hear as a crackling sound), and then back through the wire attached to the penny. This creates a charge imbalance that causes even more electrons to move. This imbalance keeps your battery going until the aluminum is used up (or more likely, the paper towel dries up!).

This experiment comes from the Oregon Museum of Science and Industry. OMSI is one of the nation’s leading science museums with an international reputation in science education. OMSI fosters experimentation and the exchange of ideas that help our community make smart, informed choices.