Solar Cell Measurement Circuit

True, the spectra doesn't matter much when you comparing similar cells, but the spectral response could be better for some cells than others. Incadesent sources are difficient in blue light which Silicon responds to. Getting the AM 1.5 spectra is very hard and expensive.

I just tried to mention it enpassing. I had to callibrate using two cells from a rotating pool of about 10. For a given session, if I used cell 1 & 2, then the next time I would use cell 2 & 3 to calibrate with.

Voc is more sensitive to temperature.
Jsc (V=0), J because it's current density mA/sqcm is proportional to light intensity.

If you want to do a quick sort.

Measure Voc. Voltage (open circuit)

Get a good ammeter or a feedback ammeter and measure short circuit current. Normalize to current density.

dv/dj (at V =0 ); 5 pt linear regression and
dj/dv (at I=0) is also useful

Max power is also useful; again using 5 points fit to a parabola.

Silicon solar cells don't get much energy from green to ultraviolet light.

They are most sensitive to red through low infrared.

Leakage requires a different setup. Usually dark exposure with voltage applied below Vmpp.

All sorts of QE's are possible. See: **broken link removed**

nC is multi-crystaline, a-Si is amorphous silicon and there is some QE info for tandem cells too.