Picture of Potato Battery Driven LED
So, if you looked at my profile you would see that I like physics.  When the challenge for “Potatoes” I just knew that I need to do a project that highlighted the lowly “Potato Battery”.  So here is how to make a Potato Battery and have it light an LED light.

Step 1:

Picture of
Galvanized nails
Shinny copper pennies
Wires with alligator clips on each end (2+ per battery)
LED bulb
Multi meter
Cutting board
MacjucomK7 months ago

trying to do this in my science Investigatory Project may I ask if how many is the required voltage for the bulb your using because i tried it with a 12 volt bulb and it took me like 10 potatoes and still no light

craftknowitall (author)  MacjucomK7 months ago

One potato battery will make about 0.85 volts. Do the Math to determine how many batteries you will need to light a 12 volt light. Maybe you will need to switch to a lower voltage LED light. Mine only needed 6 batteries to get mine to light. Hope this helps and thanks for asking.

RajeshS38 months ago

Good info. I sure am going to try it. Probably have my kid take it to school as a project.

Thanks mate..

craftknowitall (author)  RajeshS38 months ago

Welcome. I used it as a project in a class with teenagers. I thought it was fun! Thanks for commenting.

D5quar32 years ago
If the battery works on the electrolyte Potassium, is it possible to make this work with salt water? Would NaCl be electrolytic enough?
yes you can
craftknowitall (author) 2 years ago
Yes it can. Look at this Instructable to learn more: http://www.instructables.com/id/Salt-Water-Powered-Paper-Lights/.  Thanks for commenting.
MakingWorld3 years ago
science comes from the life.
Are your potatos rechargeable:)
scoochmaroo3 years ago
Woman, you never cease to amaze me!
craftknowitall (author)  scoochmaroo3 years ago
I keep coming back to this comment, it really tickles my fancy. :)
craftknowitall (author)  scoochmaroo3 years ago
When I first learned that the Challenge was potatoes, I knew that I will have to do something wild and wonderful, which meant, not my "potato soup or salad" recipes. Glad you like it.