Better Battery Mgmt or Better Battery? (Improving the COLD issue)

[aronth5]

http://www.teslamotorsclub.com/showthread.php/13633-NYT-article-Stalled-on-the-EV-Highway
There are numerous threads including the NYT article today "Stalled on the EV Highway" that discuss battery loss due to the cold.

There seems to be a general consensus on these threads that Tesla should be able to improve battery management to reduce the impact cold temperatures has on range loss. I was wondering how much of the underlying problem is the Panasonic battery itself vs better battery management? Roadster owners report the cold does not affect their range, nearly as much as the Model S. Why is that? Is the Roadster battery just better in cold temperatures or is something else, or very likely a combination? If the Roadster's improvement is related to battery management why wouldn't Tesla carry forward battery management to the Model S? What do the battery experts think?

 

[Doug_G]

I think it is due to two things. First, I suspect the chemistry in the Model S batteries likes it a bit warmer than the Roadster batteries. Second, the Model S battery pack has a LOT more exposed area than the Roadster pack.

Regardless, it's entirely manageable. You can warm up the pack prior to departing on a long trip (by charging or by using the App to start climate control while plugged in). This gets rid of any big impact.

"Range Mode" heating appears to have enough power to keep me comfortable. Maybe not toasty, but certainly comfortable in a jacket and not wearing gloves. Highway driving with Range mode doesn't seem to have much impact on range.

Driving between -3C and -20C seems to require about 20% more energy than +3C. Driving much below -20C seems to require another 10%. Not an issue at all for daily driving. For long trips it's just something to be aware of for your trip planning.