On Fri, Jun 3, 2011 at 2:28 PM, doug metzler wrote= : > we were all waiting for someone who knew what they were talking about to > jump in. But since no one did I guess I'll reply :-) > > I did this with NiHM cells and it worked really well, I had nothing > between > the solar cell and the batteries except a diode and then I had an LED > driver > chip on the other side. > > The devices were LED lamps behind a small stained glass panel in the > windowsill and I had a transistor on the cel so that duriing the day when > the thing was charging the LEDs would stay off, but at night when the cel= l > went to 0v the led drive would come on and light up the panel. > > I've been running these things for years. About every 3 or 4 years I thr= ow > a new set of batteries in. > > I don't know anything about LiPO but if you don't mind going down-tech Ni= MH > are incredibly resilient to this kind of charging. > > DougM > > I actually wouldn't mind a couple of Eneloop AAAs, but I like the tiny, flat, Li polymer cells from hobbyking. Very small and convenient for this type of thing. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .