Reports elsewhere say that charging lithium cells when they are too cold causes lithium plating which can cause short circuits and failure. Cold for a consumer grade lithium is 0-5C. No idea what aircraft grade batteries consider cold to be.
I'm sure the tech is different but I think Tesla cars do different things when the battery is cold. I believe they have a battery heater to keep it within range and I think you loose regenerative braking until the battery is warm enough.
Edit:
http://batteryuniversity.com/learn/a...the_boeing_787
Li-ion should not be charged below freezing. Fast-charging is only permissible from 5 to 45°C (41 to 113°F). Although Li-ion appears to be charging, a plating of metallic lithium can occur on the anode during cold temperature charging. Batteries affected by cold charging are more vulnerable to failure if exposed to vibration or other stressful conditions. (Some Li-ion cells are made to charge down to –10°C (14°F) but at a reduced rate.)