Drive Power cut in cold days

2014 BEV 57000miles in New Jersey - 17 degree F and over 75% SOC
Last weekend we had a one day cold spell. Temp overnight dropped to teens and single digit with windchill. In the morning when I needed to do a quick errand run (less than 3 miles roundtrip), the car's "ePower" Bar dropped to 4 bar, similar to when your SOC dropped below 5%. It limited the rate of acceleration, but I am able to get up to local speed of 35 - 40mph without any issue. I did not get onto highway to try highway speed of 55mph. This is the first time I have seen this for the 5 years of owning the car. The next morning, temp went up to 30 degree F and I got six bars total. When the temp reached 40 degree F in the afternoon , I finally got all the power back.

If it's plugged in, set a departure time. That will warm the batteries up and restore full operation. Being cold on any battery slows the chemical actions, and with less current, less power will be available until the battery protection monitor sees the temperature rise. Note, using the battery warms it some, but to have full power when it's cold out, use the departure time function. I don't remember when that kicks in, but is also is affected by the SOC.

I've never seen the ePower bars go away like that, even with the car sitting outside not charging in single-digit subzero Fahrenheit air temps. Maybe I'm just not looking for it, but don't recall ever noticing that happening. I'll keep my eyes open the rest of the winter.