Mark, Remember it is the battery temperature we are talking about not the air temperature. I have a temperature probe in the middle of my pack which is from one of those indoor/outdoor thermometers. If it reads below 0°C I just go for a short drive down and up my hill and that brings the temp up. Once I start charging the thermal mass and very slight internal heating from charging keep the batteries above freezing. If you don't have any insulation around your batteries there might be a problem if the air is really cold and the wind is blowing. Also note that this is a temperature restriction on charging not discharging. That is why taking a drive is ok and works.
On Mon, Jan 6, 2014 at 1:02 PM, Mark Hanson <[email protected]> wrote: > Message: 13 > Date: Mon, 6 Jan 2014 11:13:52 -0800 > From: David Murphy <[email protected]> > So does that mean you can't use Lithium below 0C / 32F ? That doesn't make > any sense for those who live in the northern latitudes & Canada. I charge > about .1C anyway (13 amps on CALB 130ah batts). I've charged at 20F but > tonight it'll be 0F in VA. What about folks in Minnisota like Lee? I guess > they use battery heaters but I thought most chemistries you could charge cold > just take a bit longer due to higher internal resistance.Best Regards,Mark > To: Electric Vehicle Discussion List <[email protected]> > Subject: Re: [EVDL] Charging Lithium below freezing, should I drive my > gas car? > Message-ID: > <cahtzjazxhv3i2+ugau3ms_tyrnddvywyf2-dwjkt846nd7c...@mail.gmail.com> > Content-Type: text/plain; charset="iso-8859-1" > > So the cells I am talking about are referred to as Lithium Ion Polymer, not > sure if that is the same chemistry... > The specs for these type of cells define three temperature ranges for > charging. (cell temp, of course, not ambient) > from 0C to 10C > 0.1C max Constant Current (CC) to 4.2V, 4.2C Constant Voltage (CV) to > 0.05Cmin cut-off > 10C to 23C > 0.5 max CC to 4.0V, 0.2C CC to 4.2V, 4.2V CV to 0.05C > 23C to 45C > 0.5C CC to 4.2V, 4.2V CV to 0.05C > > for discharge, the oeprating temp is -20C to 60C > > Hope that's helpful... > > david > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140106/bfe08bc2/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) > -- David D. Nelson http://evalbum.com/1328 http://www.levforum.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)
