I have feeling that about 40 percent of batteries are disposed still having lot of life in them, only because the "Oil change 3000 and battery replacement every 4 years" mentality takes 50 years to shake off.
Our family fleet had several batteries lasting 12-13 years, where one of the myths is that CA heat kill batteries prematurely.
I also hear about car batteries lasting 17 years and those are reliable reports.
Latest technology makes pocket-size digital battery testers that IMHO each RV owner should have. I still have old boxy load tester, so hold on spending money on new technology.
Than battery charging is whole science. Seems topping-off does harm them.
My 2-years old computer come with 4 different programs for charging (those are different types batteries, so not all principals are the same)
So the first choice of having batteries fully charged come with warning that it will shorten their life.
I choose longer battery life program, that will not start charging till batteries drop below 80 percent .
Comparing flooded batteries. Our Mercedes cars don't charge higher than 13.9V and those are that can run on the same battery for 12 years.
My Ford Trucks charge 14.2- 14.5V and it is hard to run the same battery for longer than 6 years.
