Too_Many_Tools wrote:
"They shut off or report error conditions, where I think the battery
can be still charged. "

I have seen the same behavior.

I have been "testing" different smart chargers to hopefully find one
that works the way I want it to.

I have had some success with using a "dumb" charger to partially charge
a battery and then to finish charging with one of the "smart" ones.

I also have had chargers NOT shut off when the charge was finished. I
have also had SLA batteries burst because of too rapid a charge rate
when using a smart charger that was meant to charge SLA batteries of
the proper capacity.

In my opinion, "smart" chargers have yet to reach a status where I
would trust them unattended.

The two main brands of "smart" chargers (Vector and Schumcher) are
showing up under different brand names everywhere....they are all the
same chargers under their cases.

I have a Vector, but I don't really trust it like I do my Solar and
Schumacher 1.5 Amp maintainers. Those have kept good batteries "up" for
5 years or more.