LED lights, or Light Emitting Diodes, were invented in 1962 by Consulting Scientist Nick Holonyak Jr, at a General Electric Laboratory in Syracuse, New York. At the time, he predicted that they would replace Edison's standard incandescent bulbs. Now, they are indeed slowly replacing the inefficient, energy hogging, high drain light bulbs.
A few years back, at school science fairs, students would struggle to light one of those blasted lights with 5, or even 6, lemon batteries. Even then, they would only glow very dimly, NOT impressing the millions watching. Well, maybe not millions, but, you get the point.
Now, those mini heaters are mostly replaced by LEDs in science fairs worldwide, but still, it would require 3, or 4 lemons, to light one.
I, being a student myself, set out to change this, set out to change the world! I forgot the story of how I thought these up but oh well!
Anyway, here I will teach you how to make tiny batteries to power LEDs.
Step 1: The Stuff!
The Stuff! Oh the wonderful Stuff! Here is a list of the Stuff you will need!
-Lighter (I used a Cheapy Laser Lighter I made with Kipkay's instructable)
-Iron Nails (Make sure they're not galvanized)
-Alcohol Prep Pads (You can use wet tissue but i prefer these)
-Copper Wire (I used enamel magnet wire)
I believe that's all The Stuff you need!
Step 2: Electrolytes, It's What Plants Crave!
In this step, we will make the electrolyte for the battery, (actually we just need to deposit salt into the paper but whatever). Anyways, start by taking your cup, and pour in like 2 ounces of water (i just made that up), or like just a little. Then, Pour a whole bunch of salt in and mix mix mix. The point is to make a saturated solution of salt for our electrolytes (because its what plants crave!). Set it aside for later.
Step 3: Wrapping the Iron Half Cell
So, basically, this step is fun (if you chose to use alcohol prep pads, if not then it isn't).
Anyway, First of all wrap the nail in the pad. Once you've done that, seat it on a non-flammable surface, make sure its tight, and set it on fire! Once the flame turns really yellow (if), blow it out. If you used tissue or paper or something, get the paper wet first, it really makes it easier.
Step 4: ElectroSaltifying the Thing
It's time to electrosaltify it! So simple, yet so easy. Just dip the nail/paper thing in the salt water then wait for it to dry. Repeat 2 or 3 times.
Step 5: Wrapping the Copper Half Cell
Another simple step, take your wire, and cut about 2 or 3 feet off. Wrap this tightly around the paper, do not let it touch the iron.
Step 6: Time to LED It Up!
By my computations, each cell gives out half a volt, meaning, that you need about 6 cells wired in series to power a standard 3 volt led. This system is not very good for powering ONE LED, but is better for powering 2 or 3 wired in parallel. Unfortunately, my cell phone died before i made this step, so no pictures. Sorry. However, the cellphones terible camera is the reason for the bad pics, sorry about that too.
EDIT: I just realized that you can probably get away with using a joule thief for just one or two cells.