Don’t go there if you’re averse to regular maintenance.
Not counting the solar panels, this is the Lair’s whole electric generation system…
It’s simple, it’s small, and mostly it takes care of itself. Every month or two it requires an equalization charge, which involves pouring obscene quantities of current through the batteries to boil the electrolyte and shake the sulphate off the plates and back into solution. (The built-in ability to withstand that sort of thing is the main reason big storage batteries are so damned heavy.) After the equalization charge, the electrolyte levels will be low so all the cells need to be topped off with distilled water. Then after another good sunny day the acid will be all nicely strong and well-mixed again.
(The equalization charge is run by the electronics, of course, and the procedure varies wildly. On my system the charge controller does it, and all you need is one button-push. On Landlady’s the inverter does it, and the command is buried so deep in nested menus I never have figured it out.)
I’m fairly good about keeping up with all that at the Lair. But in other matters my behavior is typical, which is to say deplorable. My particular batteries have post-and-clamp connectors, which offer a lot of surface area for running a starter motor – which my cabin doesn’t have – but are prone to stealthy corrosion build-up. I’ve noticed that over the past few months my top voltage has fallen off about three/tenths of a volt, which had me a little concerned. Were my batteries already deteriorating? I really did try to take good care of them. But this weekend it occurred to me that it had been a long time since I looked at the connections. Like not since they were installed.
So I turned off the inverter, took off all the cables and cleaned all the connections. Ended up cutting the end off the stranded cable between battery positive and the inverter, because it had corroded bad. Put it all back together, let the panels run up the charge, and hey presto I got my three/tenths back! Hurrah, I fixed something.
No-ox is your friend. Failing that, petroleum jelly is better than nothing. Properly torquing the connections can also make more of a difference than you’d think.
FIAT = Fix It Again Tomorrow
Alfa Romeo ; in Italian it means “rust”, truly a fiat worse than death…
I’ve got a solar system. The battery connections are still as clean as the day I installed them. As Bear said, take it all apart and smear every metal surface (battery post, cable ends, lug – all of em) with petroleum jelly. It won’t affect electrical conductivity other than to keep it good.
Now for some sunny days!