I want to be able to use it when i'm out say for a camping trip. So size is a design constraint.
Specifications :
Monocrystalline photovoltaic cell
6" x 6"
4.4W @ (STC): 1 000 W/m2, 25 °C
0.55V / 8A
Based on these specs, I would at most be connecting two cells in series.