Can I connect different voltage solar cells in series?
I have a larger panel of 21-24V, 15W and a controller with 2 solar panel inputs. I do not have enough space to put up another large panel, so I was thinking about putting a 13,5V and 4x2V cells in series.
Is this doable and a good idea? Any down sides to connecting them like this?
Thanks for your feedback & ideas in advance!