this might be a sill question but here it is anyway...
i have a couple of these lying around.
12v 1.8w
i would like to use one of these:
Mini DC/DC Step-Down (Buck) Converter - 5V @ 1A output - TSR12450

to lower the voltage from 12v to 5v so i can get my USB / DC / Solar Lithium Ion/Polymer charger - v1.0 to charge my 3.7v li-ion in lower light conditions (cloudy day/low light conditions inside my house) with these panels...
is it possible or should i just forget it???