Dave Plowman (News) wrote:
In article ,
Andy Dingley wrote:

Permeable separators is why modern batteries (last 15 years) last
twice
as long as they did 25 years ago. It's also one reason why
"Batt-aid"
no longer works, as they're pretty much already guarded against the
failure mode that might have fixed.

My experience with car batteries says they last no longer these days
than
they did 40 years ago. BMW battery - made by Bosch - exactly 3 years.
Just
enough for the car warranty. On my old Rover, which I've had for over
15
years, again 3 years or so regardless of make. And modern car
charging
systems should be kinder to batteries than dynamos were.

I'd say they design the separators to self destruct at this age.

Battery life depends on charge voltage, charge rate, what the
alternator gives out at idle, whether the car is used after dark much,
battery maintenance, alternator set voltage...

I've seen one car eat batteries every 3 yrs (bmw), and another run
happily on the same battery for 15.


NT