Hi
With the HV battery at 0c the car could only manage 4.5kwh from our 7.5 KwH home charger.
Just before this the battery heater had kicked in as the battery was at -1c and was pulling 1.5Kwh. the battery heater only starts once the car is in a drive mode. It took about 8 minutes for the battery to go from -1c to 0c.
When at a DC charger with a cold battery eg 0c the battery will heat up untill it reaches 25c. As it heats up the charge rate goes up as well.