Winter battery performance

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Not me said:
@Puppethead how fogged up do your windows get?
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I experienced no fogging at all. The air vents and fan operate while in green+ mode, blowing cold air into the cabin. Since humidity levels in the winter are in the 10%-20% range where I live there's very little moisture in the air. And the inside was as cold as the outside so there would be minimal condensation.

Blowing air is the best way to clear fogging, regardless of temperature. I once had a VW Beetle with an oscillating fan attached to the dash to blow constant air on the windshield because it fogged really badly.

The other option is to open the windows a slight bit, so what moisture there is can escape. If in green+ there's no heat anyway so letting outside air in shouldn't make things less comfortable.
 
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I definitely don't miss that. The Volt in MN was the king at fogging up, even with mild cabin heat set.

We still have a fogging issues with the SE without climate control ON here in Washington state. The moisture content is high with the rain, yet the outside temperatures will be relatively comfortable between 40F and 60F. We can usually avoid fogging by cracking the sunroof while driving. Probably no help for MN weather, but a slight improvement over opening a window.

Maybe future EVs will add heated windows all around. There are a few models with heated windshields, yet irrelevant if the side windows are opaque.

Sent from my ONEPLUS A6003 using Tapatalk
 
Puppethead said:
Cold weather means nothing to the SE batteries! Well, okay, maybe drop in e-power.

I decided to do a pure cold-weather driving test this morning. It was -3 ºF, not as cold as I was hoping for but I decided cold enough. I drove my regular ~40 mile commute completely in green+ mode (no heated seat either) to eliminate heating as a drain on the battery. I was pretty cold at the end of the 1.5-hour drive, having not worn my arctic expedition gear. Here's what MiniEVRange showed at the end of the trip:

***********************************
Feb 4, 2022 at 09:39 ** Driven: 37.8 Mi ** Start-Batt: 100% ** End-Batt: 73% ** Mi / kWh: 4.84 ** Range Left: 102.11 Mi ** Total Range (From 100% charge): 139.91 Mi ** Total Range (From 100% charge): 139.876 Mi

4.84 mi/kWh at -3 ºF! That's summer weather efficiency. No speeds above 60 mph, about half the distance at 55-60 mph. Car was fully charged about an hour before leaving, with climatization, and 100% e-power.

This confirms my hypothesis that heating uses a lot of battery in the winter. I guess the next step would be to try these runs at various cabin temperature settings.
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These results are really eye-opening, and great credit to you for making yourself so uncomfortable to obtain them. Bravo! :)
 
Almost Green said:
So reading all the comments on cold weather issues I have a question. Does the mini have a battery pack pre-warm cycle ?
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No, which is why there is a drop in e-power when the batteries are very cold. Also, charging takes longer with cold batteries. Personally I haven't noticed any performance change when the e-power drops, even when it was down to 30% for me. The only affect seems to be the maximum acceleration (torque), but the MINI's responsiveness has never changed for me.

The batteries warm themselves up as you charge/drive, although when it's sub-zero out I'll never get above about 70% e-power even with 40-mile freeway drive. But after a night on the Level 2 charger at home it goes back to 100%.
 
Almost Green said:
So reading all the comments on cold weather issues I have a question. Does the mini have a battery pack pre-warm cycle ?
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Ideal condition own EV in cold climate is to keep car in warm garage I never preheat bc I have temp. 60-70’ in winter . Driving for 1hr from warm garage I never use a heat at winter , but NY is not as cold like Il
 
Puppethead said:
No, which is why there is a drop in e-power when the batteries are very cold. Also, charging takes longer with cold batteries. Personally I haven't noticed any performance change when the e-power drops, even when it was down to 30% for me. The only affect seems to be the maximum acceleration (torque), but the MINI's responsiveness has never changed for me.

The batteries warm themselves up as you charge/drive, although when it's sub-zero out I'll never get above about 70% e-power even with 40-mile freeway drive. But after a night on the Level 2 charger at home it goes back to 100%.
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You are very brave man to own Mini SE in your climate MN.
 
Puppethead said:
No, which is why there is a drop in e-power when the batteries are very cold. Also, charging takes longer with cold batteries. Personally I haven't noticed any performance change when the e-power drops, even when it was down to 30% for me. The only affect seems to be the maximum acceleration (torque), but the MINI's responsiveness has never changed for me.

The batteries warm themselves up as you charge/drive, although when it's sub-zero out I'll never get above about 70% e-power even with 40-mile freeway drive. But after a night on the Level 2 charger at home it goes back to 100%.
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the FAQ on the website would say otherwise, but we seem to have some experienced drivers here that noticed preconditioning is only really nuking the cabin.
 
Preconditioning blasts warm air from the heat pump. It is rather nice and toasty for winter!

It was -4F today and I didn't even use preconditioning.
 
Rexsio said:
Ideal condition own EV in cold climate is to keep car in warm garage I never preheat bc I have temp. 60-70’ in winter . Driving for 1hr from warm garage I never use a heat at winter , but NY is not as cold like Il
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I’m also in NY, but I don’t keep my house at 70 during the winter, let alone the garage! The house is 58 night / 65 day and the attached garage is typically right around 25-30.

Needless to say, I often see reduced power in the morning even though I had charged in the garage the night before.


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wessy said:
These results are really eye-opening, and great credit to you for making yourself so uncomfortable to obtain them. Bravo! :)
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Yes, really 1.5 hrs of harsh winter in the name of science and SE. I also read somewhere that below 12F - the heat pump becomes useless and SE then starts using resistive heating that really kills the battery/range. You might want to test with heat on if the temp is above 12 F - with that hope to see a drastic difference in efficiency...
 
PeppyPepper said:
Yes, really 1.5 hrs of harsh winter in the name of science and SE. I also read somewhere that below 12F - the heat pump becomes useless and SE then starts using resistive heating that really kills the battery/range. You might want to test with heat on if the temp is above 12 F - with that hope to see a drastic difference in efficiency...
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I'd believe 12°F, but I've never read that anywhere. I've asked about it on this forum many times and I've been unsuccessfully searching online for the SE's heat pump/resistive heater transition temperature since July, 2019 (OK, not every day since July 2019). Is there an Android or iOS program for a Bluetooth OBDII scanner that can detect when this transition occurs? Do I have to run a wire from the resistive heater's fuse (which one is that?) to my voltmeter to obtain this data point?
 
Nobody really knows for the MINI glycol/water heat pump Coefficient of Performance. Teslas will take a huge nosedive at 12-15F with the combo R-1234YF octovalve + plate heat exchanger + glycol/water system. That's pretty much because of the reduced pressure for boiling/condensation in lower temperatures on the Tesla R-1234YF system (resisitive heaters kick in on the heat pump loop). You would have to make the heat pump loop colder than ambient air so it "heats" up the system.
 
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