Stuff you'll need:
- Small piece of cardboard
- LED (lowest voltage LED you can find)
- Thick copper cable. About 2 foot long
- Block of wood 15cm by 5cm by any thickness
- Galvanized nails about 1.5" - 2" long (MUST be zinc galvanized)
- Small panel pins/nails
- Drawing pin (could use nails if not available)
- Sheet of Paper
- Small pieces of wire
- Steel wire wool
- 2 litre plastic drinks bottle, or thin plastic
This instructable shows how to build a 5 cell version. I later built an 11 cell version in the hope of getting more light, but it's actually worse!. I guess the internal resistance of lemons is just too high.
Step 1: Strip the copper wire
Step 2: Form coils for the plates
You need to make 5 coils, and when you've done that you can attach the end of the wire to the nails, wrap around 3 turns around the nail. You want the nails to sit around 3mm away from the copper coil when they are finished.