sulfates collect and require dissipation as a result of lack o f use. i found this as i left my formosa
for 1 yr and had to re charge from 25 percent...sokmeone put my solar panels
in wrong position..LOL.....a mallet to the right location on battry was the method the rep used to "equalize" the batts that were taken in to him--is how i do mine now, saving me 50-60 per battery. is your choice. your wallet, your experience, your choice. i know what works and i do that. i learned from reps and mechanix over a period of time since 1966, when i started to drive....have fun and good luck with the batteries. mine should live another 3-4 yrs. there is a battery maintenance
site online, also--- might want to consult that site. i found it by typing in batttery maintenance
into my search bar.