Potted solar cells??

[snuffy]

I salvaged these from flashing highway barricades. (A pretty tough environment). I noticed that they are potted with a clear substance.  They seem to be extreemly durable.  I use them to keep the batts up on my motorhome during storage.  I was wondering if anyone has used anything like this?  What are your thoughts on using a potting compound of some sort on a larger array?

[ghurd]

I have seen hobby and AA-charger type panels potted.  

Also some potted 10~15W used surplus panels that were all square. Maybe square and not too large has something to do with the potting material characteristics.

There are at least a couple potting compounds available that sound suitable to me, but I'm no chemist.  It is expensive stuff at $200(?) per gallon by the time the shipping, haz-mat fees, etc are figured in.  I'm not sure if it is available to 'Regular Joes' or only manufacturers.

The cheap stuff on eBay has 'issues'.

G-

[dudevato]

tell me what potted means?  I'm thinking a 'pour over liquid that 'sets up and holds everything together?  thanks

[snuffy]

You are correct.  Thats how I believe this was done.  Potting can also mean completely submersed in a hardened compound of some sort.  Since this is a fairly thin layer over the cells, it looks like it was simply poured over them and allowed to run off as it set.

[Gordy]

Snuffy,

 A cheaper alternitive to potting, would be to get some UV protected acrylic and sandwich the cells between 2 peices of this, and seal with silicon caulking ( don't cover the cells with the caulking). If your up north like me, now is a good time to assemble them outside because of the lowwww temp and low humidity. Then bring inside to cure the silicone. You may also want to get a couple of those desicant pakets from beef jerky or what ever. Bake then for 1/2 hour at 200-250f to draw off any moister they had colected, and install them in with the cells.

Gordy

[ghurd]

Potted is solid. I expect it would be far better for those who can handle the cost and possible size limitations.

I would prefer the extra cost than the probable (and probably soon, by what I read) catastrophic PV failure.

G-

[Gordy]

Ghurd,

NO arguement, potted would be better, also permenent. If you did have a problem I don't think you'll get it apart to fix it.

I should have mentioned in my other post, to use sand paper to ruff up the acrylic where the silicone will be applied, to make a better joint.

 Gordy

[richhagen]

second Ghurd's 'and probably soon' statement.  Also, I have an old BP panel that was coated with what is stated to be 'epoxy'.  It only had a 5 year warranty as opposed to a 25 year warranty for the glass/eva/tedlar type.  Rich

[ghurd]

Just stumbled on this story.

Coldspot has an epoxy-potted PV about like I mentioned.

Surplus, square and not too big.

Lots of pic's in the link.

http://www.fieldlines.com/story/2006/8/10/134719/442

G-

[donald77777]

this may be a stupid question since im new to the solar scene, but couldn't you pot solar cells with resin that water clear.

[ghurd]

Water Clear is probably still not clear as far as light transmission goes.  High iron glass looks water clear to us, but not to the cells.

Plus most water clear potting will yellow in a fairly short time.  The stuff that won't is expensive.

The cheap stuff that is/was on ebay has serious shrinkage issues, even over a 2" span.

G-

[claude]

I have used potted cells salvaged from solar garden lights. Have a look here http://www.fieldlines.com/story/2007/4/21/194925/365 to see them.

I noticed that after 6 months the potting compound got a brown colour and lost its overall transparency. Strange thing though, it did not changed the cell's output at all. And some of them turned almost black...

Also expect scratches on their suface (outdoor means dusty winds, hail, water, etc. My cells lost their original glossy surface.

Claude