We have 10 and 30 amp our lithium ion batteries on our recumbent tandems that gives us 30 or 60 km of range although we do run at a nominal 48 V cheers then
> On 12/05/2020, at 10:54 PM, paul dove via EV <ev@lists.evdl.org> wrote: > > For range... take the weight of the vehicle and divide by 10. > > 3200lb car 320 watt hours per mile. > > Sent from my iPhone > >> On May 11, 2020, at 10:33 PM, Lawrence Rhodes via EV <ev@lists.evdl.org> >> wrote: >> >> I have just taken the first step and purchased near a hundred cells. My >> experience is with lead batteries. I want to do it right but I don't want >> to push my system. It is a 40amp controller 48-72vdc. the motor is 3kw. I >> live in San Francisco and want a little boost for my recumbent. These cells >> will put out 60 amps according to the data sheet. 1 string may be enough but >> I don't yet know if the BMS I am looking at will support more than one >> string. I don't know if the BMS and charger will talk to each other. It >> would be nice to get a complete solution. I also don't know if 2.5amp hour >> 72v system will have enough range. I have so many questions. Lawrence >> Rhodes...a good book might be in order... >> >> >> >> >> >> >> On Monday, May 11, 2020, 6:47:14 PM PDT, Marco Gaxiola <mgaxi...@gmail.com> >> wrote: >> >> >> >> >> >> A few questions Lawrence; >> >> Is the charger you'll use programmable to a desired cut off voltage? >> >> If so, What is the Max operational voltage for your controller? Maybe you >> can make your array with as many cells in series as closest to max >> controller operational voltage when cells at max. be top of charge. Usually >> this would only happen right at the end of a full charge and would last only >> a few minutes. But the more cells in series; the more energy and less >> current in the system. >> >> If your charger has a fixed top off voltage, you technically have to attach >> to that voltage and match the right # or cells in the series circuit. >> >> I'm assuming you are using LiFePO4 chemistry because of the 3.3V you >> mentioned. That chemistry, typically has a max V of 3.65V (3.7V some cases >> although I wouldn't recommend it). Typical 72V controller can support up to >> 90V operational (100Vish Max, depending on internal caps). >> >> That would be 90/3.65 = 24 Cells in series, then as many strings in parallel >> >> 87.6V charger cutoff voltage. Hope this can help. >> >> >> Marco Gaxiola >> >>> On Mon, May 11, 2020 at 1:50 PM Lawrence Rhodes via EV <ev@lists.evdl.org> >>> wrote: >>> I am having trouble deciding weather 20, 21, or 22 batteries are the right >>> series string for a 72vdc battery. for a 3.7 volt battery 20 seems to be >>> right. However I have A123 batteries and nominal is 3.3vdc. Videos on >>> YouTube are inconclusive. Sellers details not complete. Any advice >>> appreciated. I'd like to run 1 or two strings for a small ebike battery. >>> The controller only draws 40amps. Lawrence Rhodes >>> >>> _______________________________________________ >>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >>> ARCHIVE: http://www.evdl.org/archive/index.html >>> INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org >>> Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA >>> ) >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> ARCHIVE: http://www.evdl.org/archive/index.html >> INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) > > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > ARCHIVE: http://www.evdl.org/archive/index.html > INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/index.html INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
