Building a Better Battery

Did you know that you could build your own battery, using nothing more than some dimes, pennies, paper towels, and lemon juice? In this science project, you can use your homemade battery to make the needle on a compass move. You can also figure out which variables in building the battery will make the needle move the farthest.

Problem:

How a battery can be made from everyday materials?

Materials:

• Paper towels
• Scissors
• Ruler
• Pennies
• Lemon juice
• Dimes
• Insulated wire
• Nail
• Compass

Procedure

1. Cut out small squares from the paper towels, each one one-inch square.
2. Place a penny on the table.
3. Soak a paper towel square in lemon juice and place it on top of the penny.
4. Place a dime on top of the paper towel square.
5. Continue this process to build a small tower that includes five pennies, five paper towel squares, and five dimes.
6. Coil the middle portion of insulated wire around and around the nail, leaving both ends free.
7. Touch one of the free ends to the top of the stack and another of the free ends to the bottom of the stack.
8. Move the nail close to the compass. The needle on the compass should move. Measure exactly how far it moved. (You can also use a volt meter for this experiment for more accurate results. See if you can borrow one from a nearby science lab.)
9. Build other towers using smaller stacks, larger stacks, and stacks using multiple paper towel squares between each layer. Which technique makes the needle move the farthest? Why do you think this may be?