[lotharbot]

even a Volt that's not plugged in is going to be able to run its electronics for a long, long time on a single charge.

Wifi routers consume on average about 6 watts. The new Volt has an 18.4 kWh battery, which could run such a wifi router for about 4 months. Or, put another way, running a wifi router all day would use about 0.005% of the Volt's battery capacity.

Obviously a lot of other support systems would be powered on as well, but still, the point is, you're not really going to notice the battery drain from a little wifi transmitter relative to the battery capacity needed to move a 3500 lb automobile 50+ miles.

[drcross]

I think you're wrong. Most electric cars also have a 12 volt regular battery for the in car electronics and the motor battery is isolated from the rest of the car. With that said I don't know how it's charged.

[mikeash]

You could leave the car "on" to avoid that problem.

Teslas will top up the 12V battery from the main battery even when the car is "off," but I don't know how other cars do it.