[fxvinyl]

So this morning I charged to 100% in advance of a long trip today. Outside temp here in VT is currently 10°F. The app is estimating a range of 194 miles. Having read through this whole thread, I wanted to ask:

1) is this mileage estimate based on my recent / historical m/kwh of 2.6? (it has been extremely cold since the day I picked up the car two weeks ago.)

2) is the car smart enough to take into account ambient temp based on where I’m driving or the current outside temperature?

3) i note that this 194 mile range is extremely well correlated with the spreadsheet based on the 2.6 mentioned above, which makes me think it is likely very accurate. It also seems to point to the fact that the car is using recent average performance to predict my range for today. At least until we hit the road at which point if I’m driving like a maniac, the numbers would likely be degraded and if I drive very conservatively, the numbers might be better. Etc. Does this make sense to you guys? Am I thinking about this correctly?

thx.

 

[mlchem08]

So this morning I charged to 100% in advance of a long trip today. Outside temp here in VT is currently 10°F. The app is estimating a range of 194 miles. Having read through this whole thread, I wanted to ask:

1) is this mileage estimate based on my recent / historical m/kwh of 2.6? (it has been extremely cold since the day I picked up the car two weeks ago.)

2) is the car smart enough to take into account ambient temp based on where I’m driving or the current outside temperature?

3) i note that this 194 mile range is extremely well correlated with the spreadsheet based on the 2.6 mentioned above, which makes me think it is likely very accurate. It also seems to point to the fact that the car is using recent average performance to predict my range for today. At least until we hit the road at which point if I’m driving like a maniac, the numbers would likely be degraded and if I drive very conservatively, the numbers might be better. Etc. Does this make sense to you guys? Am I thinking about this correctly?

thx. View attachment 47151 View attachment 47152

Looks about right to me. To address your questions:

1) The process by which the GOM ("Guess-O-Meter") determines the mileage is opaque and we can only guess as to how it might work. I have found that your assumption of the car using its recent average consumption * battery capacity is fairly accurate in this regard.

2) I am not sure if the car actively takes into consideration the ambient temperature, but it certainly does impact efficiency in a "passive" sense. Your use of climate controls in the car will also impact this. If possible, I would recommend climatizing beforehand so that the cabin and car battery are heated up to optimal temperatures (67-68°F, as far as I have read). This should (theoretically) help efficiency.

3) Yes, based on 1). If you drive "aggressively", your efficiency and range will suffer more than if you drive more conservatively. When it comes to city driving, I am not sure how noticeable the effect is. But on the highway I can see it making a difference. However, the i4 generally has better efficency on the highway anyways, due to its low CD of 0.23.

 

[First EV]

As for point #1, putting a destination into the built in navigation will affect the range displayed on the GOM. You'll see a little road and map pin next to the GOM when this is in effect. As already stated we aren't sure what all is taken in to effect by the GOM, but knowing the speed limits and elevation changes along your route certainly would help the GOM be more accurate.
I have added a destination after we were already on our way and the GOM has change fairly dramatically at times after the route is calculated.

 

[ashley1960]

The reading is based largely on your most recent driving. If you did a 300 mile drive at 4.2 miles per kWh, unlikely at the moment as it’s Winter, then if you recharged the car after your journey then the GOM might show 340 miles as your range if charged to 100%

 

[F1Geek]

Pre condition car and range should improve. I find GOM is conservative if I drive near speed limit and am not egressive with right foot, but I find NAV accurate to within 5% SOC at destination in my experience.

 

[fxvinyl]

Pre condition car and range should improve. I find GOM is conservative if I drive near speed limit and am not egressive with right foot, but I find NAV accurate to within 5% SOC at destination in my experience.

Pre condition car and range should improve. I find GOM is conservative if I drive near speed limit and am not egressive with right foot, but I find NAV accurate to within 5% SOC at destination in my experience.

Thanks. And pre-conditioning if the car is plugged in is a matter of either a) manually activating it from the app, or b) setting a departure time, say the night before. Is that correct?

 

[F1Geek]

Thanks. And pre-conditioning if the car is plugged in is a matter of either a) manually activating it from the app, or b) setting a departure time, say the night before. Is that correct?

Plugged in so cabin and battery pack warming uses mains electricity. Sure use departure time setting or manually press button in app at least 45 minites before leaving if it is 10 F outside.

 

[ashley1960]

Plugged in so cabin and battery pack warming uses mains electricity. Sure use departure time setting or manually press button in app at least 45 minites before leaving if it is 10 F outside.

I’m sure when you press the fan bottom on the app it runs for 30 minutes and will warm the car to 22c

 

[F1Geek]

Ok. Press it twice then.

 

[nowhere man]

Does anyone definitively know whether preconditioning initiated with the app does anything to the battery?

I'm sure I've seen at least one post in the past stating that the only effect is to warm the cabin (and at least in my car it activates the steering wheel heat), and that the only ways to precondition the battery are to enter a charging station as the NAV destination or to use IDrive to initiate battery preconditioning.
Or does the app also precondition the battery?

 

[F1Geek]

Does anyone definitively know whether preconditioning initiated with the app does anything to the battery?

I'm sure I've seen at least one post in the past stating that the only effect is to warm the cabin (and at least in my car it activates the steering wheel heat), and that the only ways to precondition the battery are to enter a charging station as the NAV destination or to use IDrive to initiate battery preconditioning.
Or does the app also precondition the battery?

Time to whip out the ODB dongle and look at battery temp before and after pressing pre-condition app button.

 

[mlchem08]

I'm sure I've seen at least one post in the past stating that the only effect is to warm the cabin (and at least in my car it activates the steering wheel heat), and that the only ways to precondition the battery are to enter a charging station as the NAV destination or to use IDrive to initiate battery preconditioning.
Or does the app also precondition the battery?

From the BMW USA website (link):

This answer would suggest that the app warms up both the cabin and the battery.

 

[F1Geek]

From the BMW USA website (link):

View attachment 47259

This answer would suggest that the app warms up both the cabin and the battery.

This seems pretty conclusive. Thanks for the info!

 

[JToddK]

From the BMW USA website (link):

This answer would suggest that the app warms up both the cabin and the battery.

It was exactly that BMW statement that sent me on a search for data a little over a year ago. Using an OBD scanner, I was able to observe battery temperature when pre-conditioning for departure. Unfortunately, I was unable to observe any change, even on shore power. Admittedly, my test temperatures were modest - about the freezing mark - so I can't say it doesn't do it at all, just nothing I could measure.
Edit Add: I found my study results, Post #64 in this thread: https://www.i4talk.com/threads/pre-conditioning-energy-use.10631/post-221313

I have no doubt that departure preparation contributes to range. Many report shore power usage in the 1-2kWh range when preconditioning. Using that from the charger, instead of the drive battery on the road, is clearly an advantage.

Lord Kelvin was quoted as saying "If you can measure something and express it in numbers, then you know something about it." I've got to admit that I still know little about battery temperature when preconditioning for departure.

 

[mlchem08]

This seems pretty conclusive. Thanks for the info!

To further clarify, it seems like our app has differentiated "climatization" vs. battery preconditioning.

The "fan" on the upper right is used for climatization, which warms up the cabin. The "battery preconditioning" option pre-conditions the battery. Selecting this option shows the following notification:

 

[F1Geek]

To further clarify, it seems like our app has differentiated "climatization" vs. battery preconditioning.

View attachment 47262

The "fan" on the upper right is used for climatization, which warms up the cabin. The "battery preconditioning" option pre-conditions the battery. Selecting this option shows the following notification:

View attachment 47264

the myBMW app for my car does not have a separate battery preconditioning button, so I am going to assume pressing the fan button, as stated in the BMW official FAQ, preconditions both the cabin and the battery pack, given that the pack is cold enough or warm enough to warrant heating or cooling.

 

[JToddK]

To further clarify, it seems like our app has differentiated "climatization" vs. battery preconditioning.

The "fan" on the upper right is used for climatization, which warms up the cabin. The "battery preconditioning" option pre-conditions the battery. Selecting this option shows the following notification:

View attachment 47264

That is the behavior I observed - different functions. Precondition for departure is cabin, with (IMHO) no noticeable effect on battery temperature. There could be other, say balancing activities, that I didn't/can't look for. Precondition for DCFC, automatic through the NAV, or manual, sharp rise in battery temp in preparation for arrival.

 

[JToddK]

the myBMW app for my car does not have a separate battery preconditioning button, so I am going to assume pressing the fan button, as stated in the BMW official FAQ, preconditions both the cabin and the battery pack, given that the pack is cold enough or warm enough to warrant heating or cooling.

The last part could be critical to measurements. Maybe it only warms the battery at extremely cold temps, below where I did my testing. Frankly, I'm too warm and lazy to repeat the testing ia temperatures approaching, say, 0F. I just like the warm cabin for departure and increased range at my selected SOC.

 

[First EV]

To further clarify, it seems like our app has differentiated "climatization" vs. battery preconditioning.

View attachment 47262

The "fan" on the upper right is used for climatization, which warms up the cabin. The "battery preconditioning" option pre-conditions the battery. Selecting this option shows the following notification:

View attachment 47264

This is only for preconditioning for DC fast charging. This can only be done when the car is "On".
The fan icon does preconditioning for cabin temperature and battery temperature for normal driving.
2 different things that unfortunately have the same terminology.

 

[F1Geek]

The last part could be critical to measurements. Maybe it only warms the battery at extremely cold temps, below where I did my testing. Frankly, I'm too warm and lazy to repeat the testing ia temperatures approaching, say, 0F. I just like the warm cabin for departure and increased range at my selected SOC.

I may try to get the before and after pre-conditioning event, but I am also in no rush to do it. I press the fan pre-condition button mostly to get into a warm car and since it usually for my daily commute, the battery pack temperature is irrelevant for my typical use case.