No regenarting in cold weather

[Stefan T]

To day when took my roadster on work and should drive home there was no regenering
I check the temp on the battery and it was 9C the reganarating came back same time as temp came to 10C

It was -5C outdoors and have been below zero for some days. I have the roadster in a cold garage on the night it's only little warmer than outdoors
I have seen it ones before

Are this normal?

 

[green1]

to protect the pack it won't charge when cold, so yes, this is perfectly normal, once warm the regen will return.

 

[ViperDoc]

Frozen regen

To day when took my roadster on work and should drive home there was no regenering
I check the temp on the battery and it was 9C the reganarating came back same time as temp came to 10C

It was -5C outdoors and have been below zero for some days. I have the roadster in a cold garage on the night it's only little warmer than outdoors
I have seen it ones before

Are this normal?

Yes. As soon as the battery has warmed itself to the point it can safely be charged, your REGEN will work again! I see this in VT a lot in the winter when I have to park outside.


DJ

 

[Kalud]

Technically, charging the battery (regen) bellow 0C is prohibited by the BMS, because its a damaging process for the cell.

Many battery users are unaware that consumer-grade lithium-ion batteries cannot be charged below 0°C (32°F). Although the pack appears to be charging normally, plating of metallic lithium can occur on the anode during a subfreezing charge. The plating is permanent and cannot be removed with cycling.

Source: Charging Batteries at High and Low Temperatures – Battery University

 

[Strib]

I've just learned that this is true, of course, for a Model S. But when charging in freezing weather the initial energy is used to warm the battery; when plugged in for battery management energy is used to maintain a reasonable temperature.