My battery hasn’t been charged in a week and I’m at 205 mile remaining. Plenty of room for regen
This is correct, I have seen 55 degrees stated, but I'm guessing it's based on observation. At the end of the day, when the vehicle sits long enough for the battery pack to cool into the 50 degree range or lower, regen will be limited until the battery pack has warmed up enough to accept that rate of charge. Charging shortly before a trip (currently via scheduled charging, but soon via the coming departure time setting) is a good way for a commuter to offset that behavior in the morning, but unless said commuter can also charge at work (also shortly before departure), the issue will still likely present itself for trips to lunch and to return home.
They don't have a separate battery heater but they are able to warm the battery by turning the inverter transistors part way on. Their heatsinks are, obviously, on the battery coolant loop.
I have a suspicion (but no more than that) that the threshold has been raised a bit in recent software releases. I suspect it's now around 55 °F. Anyone else notice higher temperature regen limitiation or is this just my over active imagination?
I don't have any way of knowing whether or not an update has changed the behavior, especially at such a finite level, but I can tell you that in the two years I have owned my X, I have noticed the regen limit starting in the 50's. I can tell you that in my third year of ownership, I am seeing the same thing. Considering what I remember vs now, one thing that could be different and throwing off your perception is the overnight temperatures. For instance, I've seen the regen limited above 60 in the past two years when it was really cold when I got to work and left my vehicle but the temperature had increased dramatically by the time I got to the vehicle to go to lunch. OTOH, I've seen full regen (per IC) below 55 when the temperature was consistent between when I got to work and left the vehicle and got back to the vehicle to go to lunch.
