Any solar panel more than 15 or 30 watts - i think - needs a charge controller to prevent overcharging and killing your batteries. I have a 7amp charge controller that came with my 15 watt panel, but one of the ends is just bare wire. I don't know how to work with that. I've been looking around for instructions:
Free sun power charge control page Sun and Wind Charge Controller page But nothing is really telling me how to handle bare wires. I just don't like the idea of messing around with soldering, crimping and whatever on my own.
The Wind and Sun page has this interesting tidbit though:
"*Contrary to intuition, solar panels work best at cooler temperatures. Roughly, a panel rated at 100 watts at room temperature will be an 83 watt panel at 110 degrees."
Also, this:
"A fully charged battery is around 12.7 volts at rest (around 13.6 under charge)"
Actually there is a tremendous amount to know about batteries! I never really appreciated how finnicky they are: don't over charge, don't let discharge below 50%, make a float charge, don't let them get too hot, fill them with distilled water every month (unless it's the sealed kind, which i have because I would probably ruin a lead-acid one)...volts, amps, cranking amps...
Anyway, the charge controller will take a lot of this trouble out of my hands once I find someone to show me how to install it.
