[Martinjlm]

Originally Posted by ChevyRules

Would you allow Martin to precondition the car? As if the battery is below a certain temperature, as long as you precondition the car it will also heat up the battery to get it to temperature where it will perform better.

And having it plugged in has it using house power vs robbing battery power to do it.

Experiment should represent realistic/proper use. And for EV’s, it’s practical/realistic to precondition it before driving off.

Just like I want to know if the people in Chicago who plugged into a working supercharger but car wasn’t charging were navigating to the supercharger because that is what they should have been doing. It’s not that the cars weren’t charging, but all the energy going into the car was being used to warm the battery up before charging it because they likely failed to navigate to the supercharger so the car never got the battery to temp to fast charge.

I’m still following this one. It is starting to sound like a convergence of conditions. Whereas I originally thought it was one station it was several stations, concentrated in one part of Chicago, near one of the airports. This makes me think geography has some part to play here. Superchargers in other parts of Chicago were not as affected. They were running slower than usual due to the cold, but not as slow as the ones in this area of Chicago. The fact that it was near one of the airports presents the idea that many of the cars had been sitting at the airport for sometime and left the airport to go to charge. Two problems from this… First problem is that if the cars were left overnight or over several nights, as is common with airports, the batteries tend to dissipate about 1% of energy when sitting overnight unplugged. More in extreme cold. And if the cars were in Sentry mode they could drop as much as 15%!!! I must say that if I’m leaving my car at an airport I would want it to be in Sentry mode, so that would suck.

When owners come back to these cars with significantly reduced range, they would want to go to a Supercharger quick. Which gets to the second problem. At these extreme temperatures, the likelihood that the battery would be preconditioned by the time the car arrived at a nearby Supercharger is very low. So it’s not that the driver was negligent in not preconditioning the battery, it’s that because they were unplugged at really cold temperatures with depleted charge, they couldn’t precondition enough to aid the charging time.