How long can a battery possibly last

There is a whole science to batteries, with different requirements for charging for the different chemical compounds used.
I have been taught to use a battery that has more CCA capacity than you need because you want to push your batteries capacity to no more than 80% of it's rating-with NO science behind that hypothesis.
I did this with the civics and road runner and it works well with batteries lasting usually at least 5 years

I think the yankees in the cold place more stress trying to operate in the rigid cold than we do in the lower latitudes

i have been taught to charge a low-charged or dead battery with a trickle charger, uninterrupted to regain as much of the CCA as possible

my uncle's wingman in his f-4 (30 years ago) crashed during dake off due to mismanaged battery charging-there is maintenance to them
your smart charger (@Rainy Day Auto ) is what extends the life the most - though i wonder if it has input selection for the battery type -which should be different maintenance