>I think this is a completely different scenario. In the hypothetical desert >scenario, the vehicle operator *chooses* to run the A/C; in the parking an EV >on a cold night without plugging it in, the >*vehicle* chooses to run some >additional parasitic load without the operator's knowledge.
>I further think it is completely reasonable to assume that the operator will >not know that the battery will lose (significant) energy trying to warm itself >overnight. When you park your vehicle and >turn it off for the night, ICE or >EV, it is (or should be) a reasonable assumption that when you return and turn >it back on it will have the same amount of "fuel" onboard. >I think that rather than heating the pack all night trying to keep it warm >enough to charge (if indeed that is what happened), it would be a smarter >decision for the vehicle to leave the pack cool >to minimum operating temp, >and if later plugged in to charge, then use shore power to heat the pack to >minimum charging temperature prior to allowing charging to begin. Yes. (and better insulation) But I wanted to reiterate, that the subject here is somewhat rhetorical, even if the thermal management could be better, That's not the complete story. The problem is Musk's own data seems to be inconsistent. Did the battery lose 7.5% of it's charge or did it lose 25% of it's charge overnight? His graph of S.O.C shows it losing only 7.5%, but his estimated range shows it losing 25%. again (data here http://www.teslamotors.com/blog/most-peculiar-test-drive and original review here http://www.nytimes.com/2013/02/10/automobiles/stalled-on-the-ev-highway.html?_r=1&pagewanted=all&; I don't know but I'd guess the Tesla didn't lose 25% of it's battery charge overnight. I think it lost 7.5% of it's battery charge. But for some crazy reason chose to claim it was nearly empty when in fact it had nearly 25% of the range left. As far as I can see, what SHOULD have happened to the estimated range is to go from 80 miles to 60 miles overnight to account for the SOC. What DID happen is the estimated miles left went from appx 80 to appx 20 miles. Why?? As another note to the inconsistency you can see that on one graph you see the norwich charge as a little blip on the SOC graph, but a much larger percentage increase on the estimated range. Seems something funny is going on here. Is the a large part of the batteries capacity being held in reserve for heating on cold days as far as estimated range goes? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130218/d4a04048/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)
