Marc de Vinck - Electricity for Young Makers: Fun and Easy Do-It-Yourself Projects

Yes, you read that right. Y Were going to power a flashlight with pennies. Y No store-bought batteries here! Y Well be making our own power source with pennies and cardboard. Y Did I mention that were also building the flashlight? Y We just need an LED and a few things you probably have around the house. Y Prepare to illuminate!

TOOLBOX

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safety glassesmedium- or fine-grit sandpaperscissorspaper towelspaper or plastic cuppencil

PARTS BIN

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7 pennies, made in 1983 or laterscrap cardboard, about 6 inches squarevinegar, pour into the cupduct tape, 5-inch-long piece1 LED, red

STEP 1

Gather seven pennies that were made in 1983 or later. You can tell when a penny was made by looking at the date on the front of it. Pennies made in 1983 and later have zinc in them, which is what we need for this project.

Did You Know?

The LED, or light emitting diode, was first invented in the 1960s, but the idea of a form of light that could be produced from silicon was conceived of way back in the early 1900s.

STEP 2

Put on your safety glasses and sand one side of each penny until it has a silver-looking finish. Thats the zinc! It could take a while to sand away the copper (brown finish), but the zinc is under there.

STEP 3

Place a penny on a piece of cardboard and trace around it six different times. Cut out the six cardboard circles and put them in the cup of vinegar.

Once they are completely saturated with vinegar, take the cardboard circles out and use a paper towel to wipe off the excess vinegar.

STEP 4

Now lets build the battery. Cut a piece of duct tape about inch wide and 5 inches long. Lay it flat on a surfacesticky side up. Place 1 sanded pennyzinc (silvery) side upin the middle of the tape.

STEP 5

Place a cardboard circle on top of the penny. Place another pennyzinc side upon top of the cardboard circle. Continue to do this until youve placed all pennies and cardboard circles in one stack. A penny with the zinc side facing up should be at the top of the stack.

Make sure none of the pennies are touching each other. If they touch, it will create a short circuit, and the battery wont work. Dont squeeze the stack of pennies either. The harder you squeeze the stack, the lower the voltage the battery will produce. Red LEDs are best for this project because they dont need much voltage to light up, but if you dont generate enough voltage or if theres a short circuit, the flashlight wont work.

STEP 6

Bring one long end of the duct tape up along the side of the stack, wrap it across the top, and then down along the other side of the stack to the other side of the duct tape. The two long ends of the duct tape should meet at the bottom of the stack. Stick them together. Cut off excess tape after the long ends meet. The other two sides of the stack should remain open so we can attach the LED.