On 4 Apr 2022 at 4:54, Peri Hartman via EV wrote: > Anyway, no one has yet addressed whether my hypothesis is true or not: > if you charge while the battery is warm, it will still be able to > deliver all the kWh even when the battery has become cold (though at a > slower rate). >
And I'm not going to try, because I'm not an engineer to start with, and my knowledge of lithium batteries is even more limited than of lead batteries. However, I can speculate a bit, subject to correction from folks more knowledgable. Lead batteries lose capacity when they're cold. I don't think that lithium batteries do to the same extent, if at all. However, chemical reactions run slower at low temperatures. So while they may have the same or nearly the same amount of available capacity, you can't get it out as quickly. So I'd say that that element of your hypothesis is worth considering. I'd also guess that lithium batteries' internal resistance is higher when they're cold. That would mean more energy waste, thus capacity loss. But that resistance would also tend to warm up the battery, eventually at least partly countering the effect. I think that a fair amount of the cold weather range loss in a lithium EV can be laid to higher energy use. Lubricants are thicker; tire pressure is lower. You use battery energy for cabin heating and window defogging or defrosting. The day is shorter, so you're more apt to have the headlights on. All that is energy that isn't available to move the car down the road, so of course you'll lose range. David Roden, EVDL moderator & general lackey To reach me, don't reply to this message; I won't get it. Use my offlist address here : http://evdl.org/help/index.html#supt = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Read not to contradict and confute, nor to believe and take for granted, but to weigh and consider. -- Francis Bacon = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ 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
