In over twenty years, never had a single car go less than
seven years on a battery. BTW, the lead acid batteries used
for battery backup (in serious systems) are expected to last
on the order of 20 years. But then they sit inside controlled
environments.

Back in the 70s, a battery had to last at least 3 years (and
yes, many did not). Better material purity and better
designed charging systems (temperature compensated controls,
et al) are some reasons for longer battery life expectancy.
My last two batteries went 8 and 9.5 years - exposed to all
temperatures.

Bob wrote:
> Wow, that's the biggest load of crap I've heard in quite some time.
> I doubt if even 5% of batteries sold make it to seven years and I'm
> pretty damn sure that doesn't mean that the other 95% all have car
> problems.
> Bob