Glad you are enjoying your cells! I have been using 4.1 as my top and 3.5 as my bottom voltage. The Volt battery module was not designed to provide more than 120A current continuous based on the components found in the battery (specifically the relays in the head unit are rated for 120A continuous, but much higher surge). Or course hooking yours up in parallel multiplies that current by the number of packs you have.
I strongly encourage you to invest in some "semiconductor fuses" to protect the packs from one another when hooking up in a parallel scenario. Note: These fuses are likely to be incompatible with using a contactor style controller. The fuses are available in various amperages on ebay (new old stock). In the case of a cell failure (cells usually fail short), one pack will have lower voltage. This will result in the other parallel packs dumping current into the failed pack's remaining good cells. This can cause a dangerous situation due to overvoltage and thermal runaway on the failed pack. I believe these fuses will provide some protection from this situation in addition to providing some protection to an electronic motor controller (they are actually designed to protect high power diodes and transistors from catastrophic failure). Keep those tops on and any liquids away from them! You are correct in that they are very dangerous to work around. I strongly encourage using rubberized tools (not that it should be treated as the only safety measure). Adam On Sun, Feb 1, 2015 at 8:40 PM, jerry freedomev via EV <[email protected]> wrote: > > Hi All, Been having fun today with my new > to me 9kwhr pack of Chevy Volt modules and my deepest thanks to those > helping me get them. I finally moved from the lead era > to lithium now the price, quality is there. At $200/kwhr considering > longer life of just 2 lead cycles these are cheaper than GC batteries in > usable kwhr. And cheaper than premium lead like Yellow Tops, etc straight > up. Trying to make the best with what I have the modules > are 4 48vdc nom and one 24vdc nom. Interesting checking the cell count > the 48v, 2kwhr units have 17 cells while the 24vdc nom one only has 8 > cells. Since doing anything but 48v isn't good for me as > my controller is 72vdc nom, it looks like 4 48v strings in parallel until I > get a higher voltage controller. This leaves a 24vdc/1kwhr section > unused. A question, anyone else using these early Volt > cells and what voltages top, bottom are you using and any other details, > experiences with them? Be careful as there is no place on > the battery top with the cover off any piece of metal isn't going to short > them. And the cover comes off prying the cover from under, not move the > catch like normal. Not only am I going lithium but E > controllers I've avoided for cost reasons. But contactor controllers have > high surge loads and don't want to hurt the battery pack when I already own > an e-controller. Sure it'll be a lot less starting > power than a CC but I'll only weigh 800lbs in the new EWoody or the > FreedomEV I'll like switch the battery drive to once they, the front > suspension get tested in the E Woody. Now at only 800lbs > and very aero I think I'll get 90 mile range from each hopefully and show > what lightweight low cost EV's can > do.. Jerry Dycus > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150202/78d50c30/attachment.htm > > > _______________________________________________ > 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) > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150202/bdc41265/attachment.htm> _______________________________________________ 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)
