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Re: (ET) BB600 status and some failures.



Worse things happen. Destroying 30 BB600's is less bad than destroying 5-180's. But yes, it's possible to destroy them.

I hope you don't have trouble disposing of your wrecked batteries safely. 
My
understanding is that you usually have to pay to unload NiCds, or at least
pay to ship them to a collection point.

If I do, I do. When I got these they were with the stipulation that I would pay disposal costs, it's not many but I will check with the local recyclers and see what's what.

The one I'm familiar with is for their EV monoblocks, which I'm not so sure
they even offer any more.  The older ones have or had a straightforward
algorithm, but regrettably the GE charger is too dumb for even that.  It
requires a constant current charger and a count up / count down / shut off
timer.

Pretty much. A timer is probably the most important element, if you limit the time they can be charging you limit the possibility for damage. Second biggest is to stay away from the 1.5 volt range, that is where they gas as the final charge is done. Third is taper the charge current when you come close to the top.

The normal E20 charger does these things (only 42 volts which is 1.4vpc, timed to a day max, tapers current at about 40v) but in my case I swapped the capacitor with one that could stabilize at 47-48v. Problem is the E20 will put in 20+ amps of charge current, so it was charging too hard at the end. My guess is when one battery went dry it melted the plate separators which shorted the cell which raised the voltage on the remaining cells.

Your easiest safest route would be to buy a good quality charger designed 
to
charge NiCd batteries.  I think Delta-Q makes one.

I'll look into that. What models will work for flooded NiCDs?

If you can be absolutely sure that your GE charger never again exceeds 43v
you could probably still use that.  Most of the Saft specs I've seen seen 
to
hover around 1.40v to 1.43v per cell as a float voltage.  Charging at that
rate (42v - 42.9v for 30 cells) would take a fairly long time to fill an
empty battery, but it  should be safe for long term charging as long as you
check and top up water regularly.

That's pretty much what I have been doing for a decade with the E20; I've been running 60-90 BB600's without problems but the batteries only put out around 20-25ah per string. The E15 only had one string, so I was experimenting with ways to get that last 5ah.

And like Lithium (I'm running a Leaf pack in my 1994 S10 US Electricar) it's not really worth it.

Lesson learned.