"6. Don't use gel batteries in vibration prone environments. "

Hmm, I thought that was the idea behind gel cells partly. That the electrolyte is pretty much trapped against the plates and doesn't shlosh arond. Live nd learn I guess.

What about those battery desulfaters ? From what (actually little) I've seen of them, they put an AC current on them, which presumably somehow dislodges the sulfate from the plates.

Anything to that or is it more of a gimmick ?

Another thing, of which I am less unsure, is/was the practice of junkyards rejuving lead acid (car) batteries by adding epsom salt to the electrolyte. I don't suppose there would be any way to do that here. Also, it didn't seem to last forever.