I think for many bottom balancing can be a real solution but it takes a special talent.
I have an unreasonably heavy foot. I think even when I build a BMS I'll need to program it to cut out a bit early to save my pack from myself. I would need to identify and restrain the weaker battery at the first sign of trouble and I'd like a computer to alert me. Bottom balancing requires that I become the BMS and I'm not fastidious enough or rational enough to set battery limits in a reactive setting. The other day my Honda (off topic) had a heater hose leak. Instead of pulling over to tape it up I drove the next mile to work and hoped for the best. It worked out but if it had been a voltage sag instead I might have pushed it and ruined the pack. I need to set up very firm boundaries in advance. Not as much a $$$ decision as it is a design decision. sean On Thu, Mar 6, 2014 at 6:22 PM, Marcus Reddish <[email protected]> wrote: > BMS? Sure, if you got extra cash, but it sounds like you are working a > tight budget. If so, go bottom balance and cut charge a little early. > Fairly easy to identify your weakest cell and monitor just that one to > prevent overcharge (it will get full first). > > Cheers > > > On Thu, Mar 6, 2014 at 10:59 AM, Sean Korb <[email protected]> wrote: >> >> I don't have regen on my GE forklift motor and Curtis controller so >> that sounds about right. I'd need 1.5 of those packs plus about $1000 >> in charger and BMS electronics. I have a 40 mile round trip commute >> and a 10 mile lunch/bank run but my car is very light so that only >> uses.. well about 18kwh. >> >> I should have at least 24kwh so I don't kill the battery and I have >> some room to keep 18kwh over 8 years so that I can amortize the cost >> fully. >> >> Maybe I really only need 7 or $8000? >> >> >> On Thu, Mar 6, 2014 at 12:27 PM, Cruisin <[email protected]> wrote: >> > I have a 18kw Li-ion pack for $4000.00. You cant do better than that? >> > >> > >> > >> > -- >> > View this message in context: >> > http://electric-vehicle-discussion-list.413529.n4.nabble.com/Re-NiMH-availablity-tp4668269p4668273.html >> > Sent from the Electric Vehicle Discussion List mailing list archive at >> > Nabble.com. >> > _______________________________________________ >> > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> > http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> > For EV drag racing discussion, please use NEDRA >> > (http://groups.yahoo.com/group/NEDRA) >> > >> >> >> >> -- >> Sean Korb [email protected] http://www.spkorb.org >> '65,'68 Mustangs,'68 Cougar,'78 R100/7,'60 Metro,'59 A35,'71 Pantera #1382 >> "The more you drive, the less intelligent you get" --Miller >> "Computers are useless. They can only give you answers." -P. Picasso >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> For EV drag racing discussion, please use NEDRA >> (http://groups.yahoo.com/group/NEDRA) >> > > > > -- > Marcus Reddish -- Sean Korb [email protected] http://www.spkorb.org '65,'68 Mustangs,'68 Cougar,'78 R100/7,'60 Metro,'59 A35,'71 Pantera #1382 "The more you drive, the less intelligent you get" --Miller "Computers are useless. They can only give you answers." -P. Picasso _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
