Peri, Did you use the heater in the car when you were doing that 20 mile drive? How long did that trip take in minutes and which model year Leaf did you drive? I want to give some estimated nrs, so I can show how the distance can be so different. Cor.
On Wed, Apr 6, 2022 at 8:52 PM Peri Hartman <pe...@kotatko.com> wrote: > > Cor, this just doesn't add up, for my case. Not the heaters, but the > difference in range between cold charging and warm charging. > > Let's say I have about 2/3 the original battery capacity, which would be > 16kWh. In warm weather, I'll guess I have a range of 50 miles, perhaps > 60 if I go 40 mph without many stoplights. But, as I mentioned, in our > december cold snap, I was getting about 20. I came very close to running > out of energy, so I think 20 is pretty accurate. That's less than half > the range. > > So, if the main culprit is internal resistance, then half the energy > would be going into warming up the battery. That's a hell of a lot of > energy. I would assume that one of two things would happen: the battery > would warm up and the resistance would drop (and range improve), or it > would become plasma. > > In reality, I don't think either happens. That's why I made this post in > the first place. I have searched on the Internet but haven't found > anything beyond people's speculation. But I would think this is heavily > researched within the battery industry. > > Peri > > << Annoyed by leaf blowers ? https://quietcleanseattle.org/ >> > > ------ Original Message ------ > From: "Cor van de Water" <cor.vandewa...@gmail.com> > To: "Peri Hartman" <pe...@kotatko.com>; "Electric Vehicle Discussion > List" <ev@lists.evdl.org> > Sent: 06-Apr-22 17:27:23 > Subject: Re: [EVDL] kWh versus charging temperature > > >I presume that there are 2011 with "winter package" and heaters in the pack. > >They still have only a single HV connector on the front of the > >battery, so the HV switching is done in the car. > >I did find one inconsistency yesterday: I was taking a 2012 pack apart > >and came across a total of 8 heaters, there was an extra pair between > >the back of the quarter packs and the halfpack. > >In contrast to the 2013+ heaters, they are not all the same > >resistance: the two large heaters on the halfpack measured in at only > >1kOhm at room temp (again, resistance increased quickly with > >temperature). The 6 low profile heaters from around the quarter packs > >measured close to 4kOhm each. The heating elements apparently are the > >same, though at the large heaters the 2 power wires connect > >alternating to 5 wires that power 4 elements, hence the 4 times lower > >resistance. This also means that the power draw is much higher for the > >earlier pack heaters: 2 of 1k and 6 of 4k parallel means around 285 > >Ohms at room temp (less in the cold) so this will draw about 1.3 Amps > >at room temp which is almost 500 Watts, more when it is cold. This > >means that in a cold and exposed location when the heater is running > >the whole time that the car is plugged in, it can steal almost half > >the power of a 110V charger. > >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
