How to Make a Penny Battery from Start to Finish 

thank you! i'm doing this for my science projec at the science fair at my school

Great Video. It is the best "electricity from pennies" video on the net. However, you fail to mention just how hard it is to strip the copper off the back of those darn pennies! I discovered that it's a lot easier if you glue some 80 grit sandpaper to a board (rough side of the paper facing up) first. Then, make a wooden block (like a 2 X 4 about 5 inches long) to act as a penny grabber. Add some some grip liner (like that high grip stuff to keep things from sliding in the kitchen) to the block with some double sided tape, followed by another piece of double sided tape, followed by the penny (or pennies) - tails up (like a tape-liner-tape-penny sandwich up against the block). Try to keep the grip liner piece small for each penny so you grind more penny than grip liner. Then, turn the block upside down and rub it against the high grit sandpaper mounted on the board. You can remove a lot of copper from a lot of pennies simultaneously this way. It's still work, but not nearly as much as trying to grip, press down, and scrape one penny at a time!

@Ethan Wu: Cardboard is great. Especially if it is dense (compact and not too thick). It holds together better. I initially used some cardboard that was thick, but not very dense and it fell apart. You can also use vinegar by itself as the electrolyte.

*My school threatening us saying if I don't do this then I wont be able to walk across the stage to graduate, I'm going to try my best to try this and hope nothing goes wrong even though this a EOC school project..*

Awesome! 2:06 Grinds a penny flat, by hand, on 150 grit paper, and maintains flawless fingernails.

Had to recruit three other adults to help with the sanding. Very difficult. Ended up taking a power sander to them to get the zinc fully exposed. Not recommended that kids do that part. It should be pre-done for them. Also, the leds were not bright until I clamped the whole package together. I used cereal box cardboard and let it soak a very long time for the solution to saturate it. And cardboard that is hanging off the edges can touch the other cardboard above and below it, so that will diminish the effect. Labor intensive, but nice result.

where can i find the led light and map port squares?

Could I use a Joule Thief to amplify its voltage ?

Mr. Lincoln zincs this does not make much cents. Save your sandpaper and fingertips by using some sheet metal and tin snips and cut out small pieces to lay between intact pennies. make a more powerful battery pile with copper pennies using aluminum foil circles and a drop of bleach instead of salt water or vinegar.

How many volts does one cell put out?

Is cardboard okay?

idk whats goin on but it wont work for me i did everything right and the light isnt broken

+Exploratorium Teacher Institude why wont my led light up

I tried making this coin battery, we followed all the steps mentioned in the video, but can't seem to get the lightbulb to light. I also checked the current and voltage of the coin battery, and there seemed to barely any voltage and no current. Please help!!!

Is it legal to do this to a penny?

what if the penny isnt from 1982? what if its from 2014-2015? would it still work?

marijuana grow lights ?

Does not work.

This is stupid my dog hauteur tried it and it didn't work and by the way don't use mat board use paper towles