Lately, the performance of EVs in extreme cold has been popping up in social media. Studies do show that, like gasoline-powered cars, BEVs have poor efficiency in the cold, but once warmed up, they do much better. Numerous short trips will drain the BEV’s battery relatively quickly—as they will a gas tank.
Four FCA US employees working in Michigan considered this problem in advance of the release of battery-electric Chargers, Rams, and ProMaster vans. They developed a battery control system that detects the opening of the driver’s door, to automatically connect the battery and power up the heater and defroster, detect a start request, see if the battery is up to driving, and, if so, to let the driver know.
If the battery is not well charged during extreme cold, the car might start but have very limited power, resulting in short range. Conventional solutions provide the driver with oblique messages or ask the driver to read the manual, but the inventors thought these could be improved on. If there is not enough power to drive, the car will tell the driver so and suggest that the vehicle be plugged in to condition the battery. The driver can, while the vehicle is being charged, remain in the vehicle, running the heater and defroster. The system will also determine when the vehicle is ready to drive after being charged. (The system does allow for the driver to override the computer’s advice, which can be handy in an emergency or if the driver just wants to get the car into the garage or move forward in line for a charger.)
Among other uses, the system would prevent people from unnecessarily running the battery down to 0%, which isn’t healthy for the battery; and it may prevent people from being stranded, without preventing short periods of driving on a nearly dead battery to get the car out of the way or closer to the charger.
The patent was filed in August 2021, and was only published in January 2024.
