-20C charging 120V, Range Mode must be ON to keep going

[scottm]

If I park the car when I get to work and it's -20C and do my regular 120v/16A UMC charging ... with Range Mode is OFF the car will charge for a while then quit as the battery gets colder. At some point it just stops, and the chargeport ring will go dark blue.

If I park the car when I get to work and it's -20C and do my regular 120v/16A UMC charging ... with Range Mode is ON the car will charge for as long as it's under limit. And the chargeport ring stays green greeting me at the end of the day with a fuller battery.

In both cases, at the end of the day... battery is stone cold, regen will be OFF, and I've got a high power yellow line limiter... maybe a snowflake on the dash.

My observation is this:

Range Mode setting now seems to have an opposite effect of what it did over the last couple winters. If I left range mode ON before there was risk that charging would never start with a cold pack. In fact, that happened at a destination charger at a hotel overnight.. the next a.m. no juice added, and I had the DOH moment of realizing I hadn't turned Range to OFF. That was on a HPWC giving 40A.

Now with Range OFF, the car will stop taking on juice when the pack gets cold. This is on 120v/16A UMC. Range mode ON and the car will continue drinking even with a frozen battery.

Anyone else noticing this?

 

[Philgrover]

Could it be that with range mode off the battery heater is using all the power leaving none to actually charge with? It's about 8C here in the UK at the moment and when I went out to the car to check something earlier it started drawing ~23A at 230V just with the heaters coming on.

 

[RiverBrick]

This does seem like new behavior. Last Winter I could always charge at 120V/12A at -20C with range mode off. Of course, little to no juice would be added to the battery, but it would prevent a lot of the regen limitations.