Originally Posted by jwalker
My feeling is that as battery capacity and current delivery has increased for a given physical size of casing, they have become less reliable.
What kind of betteries were they? Regular (i.e. "normal") cranking wet cells? SLA's? AGM's? GelCell?
My personal opinion is that batteries are getting much more specialized, and the different construction techniques and physical make-ups make them somewhat more fragile than, say, automotive batteries from 30 years ago (which, I suppose, means I agree with your statement.)
Alternate construction types (especially Gel Cells, but to some extent AGM's as well) benefit in longevity from careful matching of both the load and charging rates. I don't know if the failure rates (mechanical/electrical failure) are higher than they used to be, or if they're simply easier to kill. I suspect it's the latter.
My boat has a pair of "marine" cranking batteries (supposedly a bit more robust than a standard auto battery, but not really a true deep-cycle battery); seems to work fine for what I ask of them (actually, one battery would, as well, but it came with the pair, so that's what I use.) I could probably save a bit of space by going to a pair of AGM's, but will defer that decision until I actually start having problems with the current batteries.