Hi Rob,
As long as I leave the charger plugged in long enough, the pack is
pretty well balanced. The unfortunate thing is that it took quite a bit
of reverse-engineering to understand how all the BatMon boards and
charge controller worked. After blowing the charge controller three
times, I actually modified the charge controller circuit to reduce many
of the issues I was seeing. The new charging system from Belktronix
get around this, so I can't speak for the current product.
Having the controller and the contactor powered off part of the main
traction pack also contributes to the pack imbalance which doesn't
sit too well with me. If I had to do it all over again, I probably would go
with the individual Soneil chargers and get the new controller from
Synkromotive. I've worked closely with the Synkromotive guys and their
controller matches the Zilla and has a much better user interface with
everything being configurable.
Having said that, I'll probably ride this system out and replace the
system when something breaks.