"Winter is coming..."

[Kermee]

Ah. Did you make it home/to charge?

Hah. Yeah. With 6% so worked out perfectly.

Charged to 100% and now car shows 306 miles of range. 1.3% of battery degradation after almost 7,000 miles of driving. I'm quite impressed.

 

[ReddyLeaf]

Well folks, if you don’t like it go get a 2011 Leaf. Not a single electron is wasted heating or cooling the battery (well, unless it’s a later model with the battery heaters and it’s below 4 F or something like that).

 

[ChrisH]

Hah. Yeah. With 6% so worked out perfectly.

Charged to 100% and now car shows 306 miles of range. 1.3% of battery degradation after almost 7,000 miles of driving. I'm quite impressed.

Dang! You got your car shortly after I got mine and I’m at 1385 miles!

 

[mongo]

Man, the battery gets very unhappy until it warms up after sitting in low ambient temperatures ️

It was pushing 400-600 Wh/mi at 62 MPH on the freeway (relatively flat) for about 10 miles before it leveled off back to around averages.

Keep in mind, that energy graph also includes cabin heat power usage.

Battery and cabin heating included in Wh/km?

 

[HopeToGolf]

I’m a little afraid of road tripping in this car in the winter. I’m going to have to be very conservative (meaning more charging time at stops) to feel comfortable. My last trip was my first in colder weather and I was sweating on the way home. It was my first bout of range anxiety. I didn’t realize how much range can be lost driving 80 MPH in cold weather. I arrived with plenty of miles left but I prefer a larger cushion (10%) especially when driving in an unknown area with no superchargers nearby.

It’s not a big deal per se but until now my transition from ICE to EV was relatively seamless. I regularly take ~270 mile trips which will require an adjustment in winter. Happy to have my LR battery despite its uselessness in my daily driving.

 

[mongo]

I’m a little afraid of road tripping in this car in the winter. I’m going to have to be very conservative (meaning more charging time at stops) to feel comfortable. My last trip was my first in colder weather and I was sweating on the way home. It was my first bout of range anxiety. I didn’t realize how much range can be lost driving 80 MPH in cold weather. I arrived with plenty of miles left but I prefer a larger cushion (10%) especially when driving in an unknown area with no superchargers nearby.

It’s not a big deal per se but until now my transition from ICE to EV was relatively seamless. I regularly take ~270 mile trips which will require an adjustment in winter. Happy to have my LR battery despite its uselessness in my daily driving.

80 MPH vs 70 MPH will use upwards of 30% more energy for the same distance traveled due to aerodynamic resistance.
80 vs 75 is 14%
(So watch out for headwinds)
Cold also makes aero worse in general.

 

[HopeToGolf]

80 MPH vs 70 MPH will use upwards of 30% more energy for the same distance traveled due to aerodynamic resistance.
80 vs 75 is 14%
(So watch out for headwinds)
Cold also makes aero worse in general.

Thanks for this. I did not have any concerns with the drive during summer/early fall and drove the same route/speed. I’m thinking the combination of the cold and use of the heater is what made the efficiency worse than what I experienced during other drives.

 

[R DREAM CAR]

When it gets cold, under 0 C, ice cars get low millage until warmed up may take up to 30 minutes.
So a little loss in battery power is to be expected, correct? I'll try to warm up the battery pack
before setting out in the colder weather. YMMV as always.

 

[Tezlanian]

Cold also makes aero worse in general.

Not my field so kind of curious. I heard it can affect aircraft quite a bit (good for lift, etc.) but what's the range of difference for terrestrial vehicles?

 

[Kermee]

Not my field so kind of curious. I heard it can affect aircraft quite a bit (good for lift, etc.) but what's the range of difference for terrestrial vehicles?

My guess is similarly. Air density increases as temperature drop and decreases at higher temperatures. So scientifically speaking, you would have more drag at colder temperatures. As for how measurable it is, not quite sure.

 

[mongo]

Not my field so kind of curious. I heard it can affect aircraft quite a bit (good for lift, etc.) but what's the range of difference for terrestrial vehicles?

Aero resistance is {magic_coefficient_of_drag)*({density}*{velocity}^2)/2*{cross_sectional_area}
So the drag is is directly proportional to density (thus hyperloop's efficiency and top speed)
Humidity reduces density, cold increases it. These are big factor when calculating lift for airplane max loads.
in kg/m^3:
25 C air is 1.1839
0 C air is 1.2922
An increase in resistance of 9%.

Rolling resistance and vehicle power consumption for things like the electronics and such do not scale at the same rate, so you would expect something less than 9% range loss at cold due purely to aero. If you add in use of the heaters, then the range loss will increase..
The Drag Equation
Density of air - Wikipedia

 

[Rocky_H]

Humidity reduces density,

I always thought people were making a mistake and getting it backward when they said that, but I just read some of the references on it, and the explanation does make sense. This from the Wikipedia link:
"The addition of water vapor to air (making the air humid) reduces the density of the air, which may at first appear counter-intuitive. This occurs because the molar mass of water (18 g/mol) is less than the molar mass of dry air[note 2] (around 29 g/mol). For any ideal gas, at a given temperature and pressure, the number of molecules is constant for a particular volume (see Avogadro's Law). So when water molecules (water vapor) are added to a given volume of air, the dry air molecules must decrease by the same number, to keep the pressure or temperature from increasing. Hence the mass per unit volume of the gas (its density) decreases."

Now I know, and knowing is half the battle.