Ohmmu LFP battery in a Gen 5 Prius ?

Update with the LiTime battery:

We hit some serious cold here, down to the negative thirties for a couple weeks straight. What I learned is if I shut off the car for about 8 hours, running it just before getting into bed and then just as I got out (and yes, running out there at -35 °F in my pajamas) and turned on the car, the battery would hold enough heat to not shut down completely even at those very cold temps.

At around -10 °F to -15 °F it seems kind of hard to get it down cold enough to get it to shut off with driving the car home at around 4 or 5pm the previous day and getting in and starting up at around 6 to 9am the next. Only if you leave it off all day and all night does it become a problem at those temps.

If it's just going to dip down to -4 °F or -5 °F or so in the morning, it's seemingly impossible for the battery itself to get that cold and shut off.

• So all in all, if it's getting down to -10 °F to -20 °F, then I make sure I'm driving the car at some point the afternoon before.
• If it gets down from -20 °F to -35 °F, then it's important to do something like run the car before bed and after getting up, because when you don't then you're going to have to jump start the car with another battery, which also seems to work too, it just resets all your car's computer stuff.

 

Have you tried a trickle charger to see if that will kick on the batteries heater while the Avalon is sleeping?
Do the specs say what kinda charge the heater needs before it switches on?
It's a balmy 17 F today and I keep the Prime plugged in a LOT to keep those traction heaters on alert.