I think David took a good crack at that: The battery has higher resistance so the losses inside are a bit higher and at freeway driving speed, the pack will hit minimum charge level earlier as there is a larger voltage drop (limits are almost always measured in voltage across a cell). In addition, air is denser (higher air resistance), all lubricants are sluggish and you *need* heaters to keep the windows from fogging up, even if you were not using electrical power to heat the cabin, which normally you would do as well. I even see the effect between a warm 70+F afternoon drive and a chilly 50-ish evening drive where I cannot get the mi/kWh average that I get on the same road in the early afternoon. So, no, I don't believe there is a strong temp-capacity effect. If there were, we would be seeing graphs of capacity versus temp in datasheets and I have not seen those. Cor.
On Tue, Apr 5, 2022 at 7:06 PM Peri Hartman via EV <ev@lists.evdl.org> wrote: > > So, even the 2011 has a modest heater, then ? I believe you. However, > how do you explain the vast difference between range (kWh during > charging) in winter 20F versus comfortable weather 70F ? > > Peri > > << Annoyed by leaf blowers ? https://quietcleanseattle.org/ >> > > ------ Original Message ------ > From: "Cor van de Water via EV" <ev@lists.evdl.org> > To: "Electric Vehicle Discussion List" <ev@lists.evdl.org> > Cc: "Cor van de Water" <cor.vandewa...@gmail.com> > Sent: 05-Apr-22 18:47:53 > Subject: Re: [EVDL] kWh versus charging temperature > > >Every battery I have taken apart that has heaters, has a total of 6: > >2 on top of the halfpack, > >2 midway between the quarterback stacks and > >2 in the front of the battery, next to the first high stack of the > >quarter packs. > >The resistance is in the order of 10kOhm and all heaters are in > >parallel, connecting to the full battery voltage when the heater relay > >closes. > >At an average 375-ish Voltage, the current is around 37mA which > >translates into a max heating power of around 12W per heater. > >Each heater is built up with a plastic carrier, a thin alu sheet het > >spreader and all have the same resistive heating element, though the > >resistance is strongly temp related. > >At room temp I measured about 8.7 kOhm, but even putting my hand on > >the heater element the meter quickly rose to near 10kOhm, so at any > >decent heat produced the resistance is likely to rise sharply and the > >power to fall, so they intrinsically avoid thermal runaway. > >The power likely falls to around 7 Watts per heater in operation, so > >about 40 Watts total for a pack. but a cold pack may start at more > >than 100W of power draw for heating. > >Cor. > > > >On Mon, Apr 4, 2022 at 3:31 AM Jay Summet via EV <ev@lists.evdl.org> wrote: > >> > >> > >> > >> On 4/4/22 00:54, Peri Hartman via EV wrote: > >> > I'm not sure about the newer models, but definitely no battery heater > >> > (or cooler) for the 2011 model. > >> > > >> > >> 2013 Leaf has (four) resistance heaters inside the main battery case. > >> They turn on if the temp gets below freezing. > >> > >> No active cooling in any Leaf battery so far. > >> > >> Jay > >> _______________________________________________ > >> Address messages to ev@lists.evdl.org > >> No other addresses in TO and CC fields > >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > >> ARCHIVE: http://www.evdl.org/archive/ > >> LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > >_______________________________________________ > >Address messages to ev@lists.evdl.org > >No other addresses in TO and CC fields > >UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > >ARCHIVE: http://www.evdl.org/archive/ > >LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > > _______________________________________________ > Address messages to ev@lists.evdl.org > No other addresses in TO and CC fields > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > ARCHIVE: http://www.evdl.org/archive/ > LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org _______________________________________________ Address messages to ev@lists.evdl.org No other addresses in TO and CC fields UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/ LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
