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I picked up ten 8 year old Sunpower 200 W all-black panels that had been installed without ventilation under them, and had consequently overheated. They also did not have the required 100k resistor to earth, so they are also affected by Potential Induced Degradation, which I'm hoping is reversible in this case. I got them at about 25c per watt. It looks like it will be a reasonable deal, but only if I value my time very lowly (and also my wife's time; she expressed and interest and has been helping a lot.)
Visible on the bench:
* Heat gun, set to 125°C, for softening the backing, black potting, and EVA (Ethyl Vinyl Acetate, the stuff that goes between the cells and between the cells and the glass).
* Temperature controlled soldering iron, with a "battle axe" shaped tip.
* Many repairs, with duct tape covering silicone "pods". They have a letter and digit code indicating their position. Three repairs have been marked up but not yet started (B2/C2/D2).
* Magnifying lamp with 60 LEDs, used mainly as a light source. Occasionally I'll actually look through it.
* Power supply and multimeter, used to check for shorts after a repair, and to find joints that are sensitive to pressure. The multimeter probes are pushed into the junction box at the back of the panel (at right of the photo). This junction box is very useful since it allows access to the joins between sets of 24 cells (these are 72 cell panels).
* Silver and gold felt tip pens; these are used to make visible lines and markings on the black backing and duct tape.
* A blanket covering the table, to minimise scratches. This may later be used as a wet blanket in PID reduction experiments.
* Flat blade jeweller's screw driver, used for removing the backing at the start of a repair, and scratching a small area to solder for the repair itself.
* A chopstick (near the F1 repair), used for pushing softened EVA and black potting away from the back of cells. I much prefer the ones (I think from Noodle Box) that have a triangular end. The intention is for expert chopstick users to be able to control the sticks better; it turns out to be a wonderful wedge shape for scraping without damaging. (Though it's still possible to crack the edges of cells.)
* Some rolls of duct tape. As you know, this stuff holds the universe together.
* Plastic "stanley" knife, for cutting the black backing, and also some black plastic under the straps that join cells; with my repair technique, some of this plastic that sticks out has to be trimmed away.
* Small needle nose pliers which close very well. These are used to prise the black backing off.
* Markings on the back of the panel for cell borders, and three repairs marked up ready to cut the backing material.
Not visible in this photo:
* Silicone caulking gun. Silicone replaces the EVA and waterproofs the repair. The duct tape basically holds the silicone in position, and will no doubt come off in time.
* A dressmaking pin held in a clip lead. One of the tests after a repair requires a connection to a strip of copper that is only about 1 mm wide; the pin helps make a precise connection, and also helps penetrate any oxide on the copper, and/or vestiges of EVA.
The original thought is that each panel may need up to six or so repairs. Unfortunately, there are very few panels with less than 10 repairs, and most of those will need many more. Several panels have more than half the junctions repaired; several "thirds" (sets of 24 cells terminated in the junction box) needed all 22 joins repaired. (The outside connections seem to be much more reliable; I have only 3 or 4 connections to "row L" (right at the bottom of the panels), and none so far to "row @" (at the very top of the panels).
Thanks are due to Weber for getting me started with the repairs, and the idea to attempt them in the first place.
[ Edit: Sorry, there is very little EV content here, except that perhaps one day these panels will charge an EV. I post this here because I know that many EVers are interested in solar power. ]