On 08/07/2017 10:58 AM, Matthew Quitter via EV wrote:
Thanks Bill, sorry I'll try and give you more information.
I'm using a Zivan NG3 charger and don't have a BMS at the moment, just a
bunch of QNBBM cell balancers.
Previously I stopped the charge manually when the Curtis was saying 100%.
The Zivan also displays a charging progress and it would also be at 100%.
But lately the Curtis is saying 30% when the Zivan is showing 80% complete
and some of the cells are starting to jump up to 4V during that phase of
the charge. Whenever a cell goes over 4V I've been stopping the charge and
allowing the cell balancers to even out the pack again.
It is good to hear you have balancers. You seem to describe a pack that
is not well balanced. It is a new pack? Never before balanced? Once
you get it balanced your troubles will almost certainly diminish and the
balancers will tend to improve things with each full charge. One
balancing strategy would be to contrive to charge at a low rate once so
that your balancers can keep up. A charger that charges at a lower rate
than the balancers can pass. As Lee Hart might suggest, you might use
some combination of incandescent light bulbs for current limiting.
Another strategy would be to get one or more single cell chargers and
charge all cells with it/them sequentially.
Read EVAngel's EV News at http://evdl.org/evln/
Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)