thanks! It might not take as much to warm the battery as you think if the the battery is being charged at the same time. the last 20% of charging has added resistance and thus creates some heat of it's own. Until I can actually see the battery temp I won't know for sure, but so far, if the battery is cold soaked to say 35 degrees, 4 bars, I can, with a good prewarm raise the temp to 5 bars and it apparently takes on more charge. Since I'm preheating at the same time, I'm not able to isolate how much of the juice is going to the climate control vs charging and to add mud to the water, it appears that prewarming also allows some amount of safe "overcharging" of the battery. Additional charging can not be measured easily. the prefered way to measure charge on this board seems to be to measure how much the battery takes to "recharge" to 100%. since we haven't been able to see the battery temp and can't really nail down the floating voltage ratio to charge held precisely, there will probably always be some unknowns here. I'm looking forward to Phill's Leafscan to finally be able to track battery temp under various charging and discharging scenarios.
I have seen enough already in terms of the benefits of a warmer battery to consider insulating my garage, something I've been wanting to do anyway. aside from saving $$ on heating the house, it will also allow me to reasonably control the battery environment during charging. The battery has enough thermal mass to benefit from prewarming for quite a while.
brent wrote:My guess is the the battery pack would take a pretty big whallup of juice to heat it up so it might need some priority setting.
Charge first priority ... after 80% start the battery warmer or something like that ... and I said manually, I really mean timer / manual control. I think Bill Gates had a hand in the software. Please don't try to guess everything I want the car to do in advnace and then lock me out of the decision loop.
Love the handle ... GaslessinSeattle.
Gasless: Silver 2012 SL, traded in for Lease on 1/13
Tesla S P85, Gray, pano, carbon fiber, took delivery: 2-9-13... LOVE this car!
9.8 kW PV Solar installed 9/12, http://www.westseattlenaturalenergy.com
" onclick="window.open(this.href);return false;