on 5/12/12 8:22 AM, David Morse wrote:
I am curious though, does anyone have evidence that the cool down feature in beneficial? If so, I wonder why this is something Tesla never implemented.
Tesla recommends that you plug in the car whenever you can and especially if the battery is hot. This is problematic if your electricity is billed on time-of-use, or you want to do your charging off-peak for some other reason. So for days when you arrive home with a hot battery during the day and want to be nice to the battery, but also want to limit your use of power during peak demand hours, a cooldown feature is highly desirable. I installed a Tesla Tatter last summer and used the cooldown feature a lot, it's very nice. It is an open question as to how beneficial it is to battery longevity. Drawing lots of current from a hot battery is definitely bad for battery health; that's been proven by several Roadster owners. It's less clear if letting a battery pack sit hot while drawing little or no current is a problem. To delay a $40,000 battery replacement, I'm happy to err on the side of caution. In August of 2009, I asked Tesla to implement a cooldown feature and was told: "The idea of allowing you to cool the pack while only pulling enough energy from the wall to do so is something that we've talked about. Unfortunately, although the idea is simple, there are some significant hurdles in implementing." That didn't stop Scott451 from doing it, with no help from Tesla. Now Scott works for Tesla. Tom