Voltaic batteries of all shapes and sizes are objects that convert chemical energy into electrical energy. You probably use batteries to power your cell phone, iPod, or any number of wireless gadgets. But did you know that you can actually use chemical energy stored within a lemon to power a small LED light? It's true, and we'll show you exactly how in the Fruit-Power Battery experiment.
- Four lemons (the bigger and juicier the better)
- Four pennies
- Five zinc-galvanized nails
- Five sets of alligator clips
- LED light
- Kitchen knife
- Use a kitchen knife to cut a penny-sized slit in all four lemons.
- Insert a penny halfway into each of the four slits that you cut.
- Push a zinc-galvanized nail into each of the lemons, opposite the penny. Be sure you don’t let the nail and penny touch each other.
- Connect all four lemons together with alligator clips. Each set of alligator clips should connect a nail with a penny.
- Attach the two loose alligator clips to the LED light.
- Check that out! The energy from the lemons lights up the LED.
How Does It Work?
- WORKED FOR OUR LARGE HOMESCHOOL SCIENCE CLASS! Review by Kirsten
This is a great project and worked well for our class. A couple things to help have success:
Warm the lemons up by soaking them in hot water, that will make the juices flow, we made sure we had good juice flow by also lightly bruising them on the table.
Use pennies from 1979 and before for higher copper content.
IF the LED doesn't light up simply unhook from the light and turn the light around and try again, the current needs to flow in the correct direction to light it.
Darken your room. Or we used boxes turned on their sides to create a shadowed area.
(Posted on February 28, 2013)
- to Liz Review by Eva
Liz, did you try a different LED light?
(Posted on April 25, 2012)
- The type of LED will make or break the experiment!!!!!!! Review by Julie
We first tried a readily available flashlight LED... too much resistance. Went to Radio Shack and got a 5mm Red 1.8volt LED and it worked great. We also made our own alligator clip cables by purchasing inexpensive clips at Menards and attaching them to wire from old Christmas lights.
(Posted on November 12, 2012)
- No light for us Review by Payton
We were unable to get this experiment to work. We used the 5mm 1.8 volt LED light and even increased the number of lemons all the way up to 7! We checked the voltage of the circuit created from the lemons and it had ample voltage (3.9 v) but would still not light up the bulb. We verified that the bulb worked by using the an alligator clip & connecting it to two AA batteries which caused it to light up. We have no idea what went wrong....
(Posted on February 21, 2013)
- Other Items Review by Keely
Can anyone tell me any other lights or item that would work in this circuit as well?
(Posted on July 18, 2012)
- the type of led light matters Review by Bam
I tried an old christmas light and it didn't work. So I used a 1.8 volt 5mm light from the source and it worked perfectly it stayed lite for over3 hours
(Posted on January 12, 2013)
- Steve's lemons Review by Pam Osborne
This guy is a genius resource of science fun. Lighting up leds in this way will also impart a lemon-fresh aroma to your kitchen, or wherever it is that your mom lets you set it up. Another good thing about this particular experiment: It won't shatter windows or spread sticky green slimy stuff all over everything in the house/garden/garage/your bedroom.
I should mention the music. It's so cheerful!
(Posted on March 22, 2012)
- Great simple experiment Review by Mafrlene Thomas
I am the Director of an afterschool program serving kids kindergarten through 5th grade. Each week I do a science experiment for "Really Really Wierd Science". This experiment was a segway into a month of electricity and the kids absolutely loved it. I do not try the experiments beforehand and am always concerned if they will work. No problems with this! I added a fiber optic to the bulb for some added effect. This week we made the battery...next week we make the bulb!
(Posted on April 4, 2012)
- Lemon experiment Review by Liz
It didn't work. Used very juicy lemons, dirty pennies, clean pennies, more lemon in series. No lighting of the LED.
(Posted on March 27, 2012)
- Voltage for the LED light? Review by Brylyn
Anyone have a specific voltage that they used? I have 3.3 volts, but they don't seem to be lighting up. Thanks.
(Posted on October 8, 2012)