Introduction: Octanis 1: How to Make Solar Panels
Octanis 1 will fly to Antarctica and land a satellite controlled rover. To do this, it needs lots of power and it will get it from the sun! Here's a guide on how to make Octanis' solar panels.
Find out more about the rover mission: http://octanis.org/
Step 1: Cut Your Cells
Cutting solar cells is the trickiest bit and this step depends on the type of solar cell and cutting device you use.
We used Sunpower C50 cells, that can be cut with a diamond glass cutter. It's enough to score the cell with precise force and then snap it carefully, hoping it will snap along the cut line. The yield for this is about 50%, so make sure you order enough cells!
Step 2: Clean Them
Use a sonicator bath to clean the cells. Make sure they don't overlap or touch each other as this would produce nasty stains.
Step 3: Prepare the Solar Panel Foundation
We will use adhesive foil as a layout guide and an easy way to keep the cells together when flipping them around after soldering.
Cut the adhesive foil to size (Octanis 1 has a panel size of 30cm x 30cm). Peel off the adhesive foil and set it aside. Place the non-adhesive side on a flat surface. Spray the clean solar cells with distilled water to get rid of dust.
Step 4: Layout & Solder the Cells
While the cells are still wet, place them on the non-adhesive side. Make sure you align them correctly (pay attention to the polarity).
Then solder them together using solar tabbing (get it on eBay). Octanis 1 uses a 7s2p (7 series, 2 parallel) configuration. Soldering is straightforward, use solder tin if necessary. Solder as you would solder a PCB.
Make sure you make the tabbing that goes out (where you will connect your load) is long enough.
Step 5: Prepare for Epoxy Pouring
When you're done with soldering, carefully stick the adhesive on to the solar cells. It should be sticking on the back side of the cells!
Turn over the panel and peel off the non-adhesive side.
Tape it onto a flat surface, make sure the tape is very strong. The epoxy has the potential to unstick the tape if it goes underneath it.
Step 6: Make a Border Out of Tape
... so the epoxy doesn't flow out. Again, this needs to stick well!
Step 7: Pour the Epoxy Resin
We used 10:6 two-part resin from OBI. For a panel size of 30x30cm we used 90ml of resin (A: 56ml, B: 34ml)
Step 8: Let the Resin Cure.
For faster curing (less than 5 days), leave it under a UV lamp.