Fixing broken solar panel glass with a silicone encapsulant
I had a new solar panel propped up against a tree and it got knocked down by the wind and shattered (PSA, don’t do this). The panel was still giving good current, however with the broken glass water would have quickly worked its way in and started corroding the components. Rather than replace the panel I decided to make an effort to repair it (the warranty was voided anyway).
After giving it some thought I settled on a clear Silicone Encapsulant from Quantum Silicones called QSil 216. This is a liquid silicone that cures into a solid flexible rubber-like material which protects electronics from moisture and vibrations. It has a low viscosity and works its way around components as it cures sealing everything together.
In the video you can see how I used a piece of wood to apply the product. I had a comment that this may scratch the solar cells, however the glass was still mostly intact and covering the cells so the wood never touched them. Here is what it looked like after I finished:
Temperature and Humidity during the cure process
The data sheet for this says it’s supposed to cure in 4 hours at room temperature, what I found is that it took MUCH longer. I had it curing for a total of over 36 hours between 65 and 80 degrees Fahrenheit (that’s 18 to 27 for those of you in the rest of the world) and about 35% relative humidity. Thanks to one of my sensor projects I have a log of the temperature and humidity in my garage over time so I was able to produce a report during the duration of the curing process:
It cures clear, and in the video above you can see it’s highly flexible. Here is a close-up of the cured product that remained in my mixing cup when I was done:
As far as I can tell it’s working fine after the repair. However it’s October, I have it mounted in a area that gets a fair amount of shade, and I don’t have any identical OEM panels I can test against so I don’t know for sure how we’ll it’s doing as compared to when it was new.
If anyone has a good suggestion for how I might test the output of this panel as compared to original specifications I’d love to hear your ideas. Please post in the comments!
Hope this helps if you find yourself in a similar situation.