Hello,
I see one solar cell available in Fritzing. This part is tagged as solarbit-12x1.
A generic data sheet seems to indicate that the negative lead would come out of the top of the cell, when it’s not coming out of the right side.
https://www.mouser.com/datasheet/2/205/xob17-solar-bit-datasheet_mar-2008-1170629.pdf
And of course, the data sheet images lack a notch, which I half remember goes on the left.
Could the part get some basic plus (+) and minus (-) symbols to clarify?
Could more parts include a PDF link to their data sheet?