Winter range/regen battery conditioning question

[Reason]

Good morning folks -

First season of my MX ownership so trying to figure out best use. Dropped under freezing (32F) for the last two nights, and I noticed this AM that even after preconditioning the car still had limited regen the whole time driving to work. I thought preconditioning got the car ready to go at regular potential - kindly help me figure this out.

Some details that could/should help.

1) overnight charging ended about an hour before I had to leave
2) cabin set at 70
3) Range mode on
4) commute is relatively brief - teslafi screenshot attached.

Screenshot of dash on arrival



Thank you in advance!

 

[Big Earl]

Range mode ON actually disabled the battery heater, so it is not preconditioning your battery. You may also find that it supercharges slowly or not at all (in very cold conditions). If you turn range mode back off, you should see a significant improvement.

That said, range mode is perfect for short commutes, as heating the battery for a short commute will use more energy than regen will recover. Your overall efficiency will probably drop, although it won’t look like it in TeslaFi since it doesn’t display energy used for preconditioning.

 

[Reason]

Range mode ON actually disabled th battery heater, so it is not preconditioning your battery. You may also find that it Superchargers slowly or not at all (in conditions). If you turn range mode back off, you should see a significant improvement.

That said, range mode is perfect for short commutes, as heating the battery for a short commute will use more energy than regen will recover. Your overall efficiency will probably drop, although it won’t look like it in TeslaFi since it doesn’t display energy used for preconditioning.

Thanks - I'm surprised range mode still is "on" even when charging overnight. That seems like a problem for cold weather users. FYI the car preconditions for supercharging so that is always (reasonably) quick.

Also, where in official documentation does it show range mode turns off battery warming? It is not in the user manual. I've seen the discussion about it on the forums (hence the inclusion in the possible data).

Interesting that teslafi shows poor efficiency at home charging (see screenshot). Will test charging this evening to see if efficiency goes up with range OFF.

 

[Big Earl]

Thanks - I'm surprised range mode still is "on" even when charging overnight. That seems like a problem for cold weather users. FYI the car preconditions for supercharging so that is always (reasonably) quick.

Also, where in official documentation does it show range mode turns off battery warming? It is not in the user manual. I've seen the discussion about it on the forums (hence the inclusion in the possible data).

Interesting that teslafi shows poor efficiency at home charging (see screenshot). Will test charging this evening to see if efficiency goes up with range OFF.View attachment 604678

Interesting data from TeslaFi. Tesla may have changed range mode so that it will preheat the battery for charging, which would explain your poor efficiency. The 1,000 pound battery pack takes a lot of energy to heat up, and if you're only recharging after a short drive, it can take more energy to heat up the battery than it actually adds to the battery.

Based on your description, it sounds like range mode still disables the battery heater for preconditioning, which would explain why you still had extremely limited regen after preconditioning.

Unfortunately, there is no documentation that I've found, so we're left with collecting data and coming to our own conclusions.

 

[Reason]

So, with range mode OFF, the efficiency of home charging is much higher (70+) percent instead of 20something percent.

Yet, full regen was still limited this morning when shifting in to drive. Is this normal? I expected the conditioning to have fully... conditioned.

 

[Big Earl]

So, with range mode OFF, the efficiency of home charging is much higher (70+) percent instead of 20something percent.

Yet, full regen was still limited this morning when shifting in to drive. Is this normal? I expected the conditioning to have fully... conditioned.

With range mode off, the battery was probably warm enough from your recent drive to allow charging without the system having to heat up the battery, causing the charging session to be more efficient. However, the following morning drive was probably long enough after the charging session that the battery cooled back down, causing the limited regen that you experienced. Did you preheat before departure?

 

[Reason]

Thanks - yes, preheat/condition was set (60 in the cabin, for ~630 or 645 departure). That hasn't changed. But, there remains the dotted yellow line