So I'm able to get these for free, there's 26 of them in total but only brought back one to check it out, I think they're 210Ah cells.
Only thing is I'm pretty sure the last time they've been used is at least 15 years ago .. has anybody had any success in getting old batteries to work?
They seem to be in pretty good condition physically, they've not dried out and are still full of acid, there is some sediment at the bottom, see photo, but it's not reached up to the bottom of the plates.
They're currently showing 20mv!
So.. I'm thinking of trying to charge them up and see what happens, can somebody remind us of the voltages I'd want to be reaching for a single cell?
And maybe seeing if I can take the cell apart and filter the acid to get out the sediment, check the s.g .. but I only have a wine hydrometer so not quite sure if it's in the right range and it also needs a lot of liquid to float in.