Electrical – a suitable material to cover photo voltaic panels

enclosurelightportablesolar cell

I'm building a small, portable, modular solar panel array to charge 5V power banks, phones, etc.

I got most of the electronics down, the Step-Up converter, by-pass diodes, blocking diodes, as well as JST connectors are somewhat in place, but now I'm struggling a bit in building an enclosure for them.

The idea is, the cover or case should be made from soft material, I was thinking Dacron backing, and using either Nylon or Polyurethane fabric as cover.
But the tricky bit seems to be the cover for the active surface, that gets exposed to light. The problem is, using a material that doesn't impede the functionality of the panel too much. It doesn't have to be soft, as the panels aren't bendy themselves. I was thinking perspex (Plexi-Glass), but I'm not sure if that will filter out the wavelengths important to the panel.

There are these waterproof bags for tablets and smartphones available, they have a translucent front, which is soft and glued/welded to the rest of the plastic container. Unfortunately, I wasn't able to find out what sort of material that is (otherwise I'd have ordered a sample of it from AliExpress or something).

So, what sort of plastic should I use to cover the panels with?

I don't wan't to use glass. It's supposed to be carried either in a pocket or a backpack, so something that can shatter like glass would be too dangerous, obviously.

Best Answer

Most of the sun's energy is in the visible band, so anything that looks good to the eye will perform well. clear PMMA (perspex) or polycarbonate (Lexan) seem like suitable sheet materials.