What difference does cold weather make to battery range

What difference does cold weather make to battery range

KP in NPT | 3 novembre 2016

quite a bit - which is why a bigger battery in cold climates is a factor for many. That said, we have a 70D and while we definitely had to charge more often/longer when we were traveling during cold/snow/ice, it wasn't so bad that we regretted our "smaller" battery, despite making regular long trips. But a bigger battery would be better if you're willing to pay for it.

tstolz | 3 novembre 2016

Depends ... I live in Alberta so I guess I know a little about this. I keep my car in a heated garage ... so I don't see much of a decline in winter at all unless I let the car get cold. If the battery needs to heat itself you will definately see a decline! If you do lots of short trips with the car getting cold in between .. it can really affect range. If you start with a warm battery via a heated garage or via pre-charging before you leave ... it isn't bad ... in fact I've gotten close to EPA in the winter this way on long trips.

KP in NPT | 3 novembre 2016

I agree with tstolz - our car is not garaged but preheating makes a big difference.

Red Sage ca us | 3 novembre 2016

I keep forgetting people live in places where there is weather.

gregcropper | 3 novembre 2016

Perhaps a Model S owner can answer this question. Since the superchargers charge faster for the first 80% of the charge, would having a larger battery mean that you would get more miles of charge in the same amount of time?

JeffreyR | 3 novembre 2016

See TMC: @Doug_G's "Cold Weather Driving" Blog — The one I always reference when people ask about dealing with the cold.

I keep a list of useful/interesting posts here:

Red Sage ca us | 3 novembre 2016

gregcropper: Yes. If a Model S 60 and a Model S P100D both arrive at 20%, the Model S P100D will add more miles in that first half hour of Supercharging.

dsvick | 4 novembre 2016

@tstolz, you said start with a warm battery ... via "pre-charging". @mp, you said "preheating". Is that the same thing? Does it happen automatically if you just leave it plugged in all night? Or do you need to actually use the app and tell it to do it?

KP in NPT | 4 novembre 2016

Sort of. In cold temps your car has a battery temp management system that uses energy whether your plugged in or not. Preheating the cabin also uses energy. So if you're plugged in you will replenish lost energy and warm the battery in the process. At least I think that's how it works.

EaglesPDX | 4 novembre 2016

Tesla has a range estimate that allows you to plug in temperatures and heat on and see the effect on range. Just click on the TS link at the top menu bar and scroll down to see the range estimator.

tstolz | 4 novembre 2016

I just meant charging before you leave on your trip.

dsvick | 4 novembre 2016

Ok, so do you get any benefit to range from warming the car up before say going home from work where the car is not plugged in?

KP in NPT | 4 novembre 2016

If you can spare the range then yes, it will get you to regen faster.

dave.m.mcdonough | 4 novembre 2016

If the car preheated itself while plugged in before I left in the morning, that would be awesome.

Haggy | 4 novembre 2016

If Tesla has something similar to their current batteries that can be upgraded, then charging at a supercharger might be fast even for a "smaller" battery. If you have a 60 that can be upgraded to a 75, even if you charge the 60 to 100%, you'd be charging the physical battery to 80% so you won't see a big slow down when you get to the final 10%. Whether Tesla will have software limited batteries for the Model 3 is an open question.

The Model S can be preheated before a trip by using the app. In theory, the car can also try to figure out your schedule and anticipate when to heat or cool the car for you. When the feature first came out, many turned it off since it needed work. It's possible Tesla made it a lot better, but I haven't tested it recently.

EaglesPDX | 4 novembre 2016

@tstolz " If the battery needs to heat itself you will definately see a decline!"

Tesla range estimater says that in below freezing temps with heater on, the range of a T75D (closest current equivalent to long range T3) would be 228 miles. Going uphill 65 miles to 6500 foot elevation in slush, snow and ice with snow tires is going have a big impact on the 228 miles. Might get to the parking lot with 75 miles left.

Then the car is going to sit in 10-20F environment for near eight hours and the battery heater is going to be working over time and then have to defrost the car to drive out. I wonder if the battery would make it?

EaglesPDX | 4 novembre 2016

Found this range chart from a TS85 owner on "Insideev's"

KP in NPT | 4 novembre 2016

Vampire drain during extreme temps for me was about 5-7 miles a day last winter, including days with sub-zero temps. I think the worst case drain is around 3% for an entire day. So yes the battery would make it.

EaglesPDX | 4 novembre 2016

Article had these guides on range estimation in bad weather (good weather if you're a skier).
"How do you best prepare for winter driving in your Tesla Model S?

Expect to use (on average) 40% more power during the winter.
Expect to lose about 10 miles of real range for every 10 degree drop.
If the roads aren’t dry expect to lose up to 25% more range.
Plan your charging and driving accordingly — don’t cut it close.”

Using a 270 mile range T3 with AWD (which should help the efficiency in regard to slush/ice/snow road) for my 65 mile run going up 6500 feet in 10F weather, I'd guess I'd lose 65% range and show up with 95 mile range.

So for car sitting eight hours in 10F weather, how much battery range would I lose from the battery heater (8 hours) and cabin heater's 10 minutes to defrost?

EaglesPDX | 4 novembre 2016

@mp1156 "Vampire drain during extreme temps for me was about 5-7 miles a day last winter, including days with sub-zero temps."

That's not bad. If I figured conservatively for 10 miles drain for 8 hours in high altitude sub freezing, I'd have 85 miles left. I'm sure downhill would be regen the whole way even with the battery/cabin heater on so as long as I can get going with even just 40 miles left, I'd be OK.

KP in NPT | 4 novembre 2016

Definitely not 10 miles for 8 hours. I don't think I had 10 miles in an entire day even on days it was below zero.

I went away for 5 days and left my car unplugged in a parking garage (that was open and at ground level so not warmer than outside) to avoid it getting buried in a nor'easter. It was in the 10s at night and teens maybe 20 during the days. I don't think I lost 30 miles.

JeffreyR | 4 novembre 2016

One trick is to have the car charge a bit a little before you plan to leave. That will pre-condition the battery and you can also heat the interior. If you don't what time that will be just change from 70% to 80% (or similar adjustment) before you are ready to go.

EaglesPDX | 4 novembre 2016

@JefferyR "If you don't what time that will be just change from 70% to 80% (or similar adjustment) before you are ready to go."

I think I'd need the battery at 100% before I went. At 30-20% down at departure when I'm going to lose 65% on the ride up the mountain plus the vampire loss of the heater in the cold high altitude would seem to be cutting it too close. Going from sea level up to 6500 feet, pre warming at the start is not necessary but pre-warming the car prior to leaving the mountain would be necessary for comfort and for defrost.

JeffreyR | 5 novembre 2016

Then go from 90% to 100%. The point is to do a bit of charging just before you leave to condition the battery. Also heat the inside of the car on land charger instead of battery, then switch to seat warmers instead of forced air while driving. Doug_G has the details.

EaglesPDX | 5 novembre 2016

@JeffreyR "The point is to do a bit of charging just before you leave to condition the battery."

That car would sitting outside with the charger being on all night, no different than any other day. I'm hoping I can turn on the car heater/defroster 10 minutes before I go just about every day in winter, ski day or not. Kind of like the remote start on my Subaru (which does put a dent in the MPG in the winter). Of course five minutes of that is for the engine to get warm, with the Tesla being electric heat, it should only take 5 minutes to defrost.

KP in NPT | 5 novembre 2016

You can turn on the car to preheat every day in the winter - from the app on your phone.

tstolz | 5 novembre 2016

EV Trip planner is a great on line resource - it accoubts for all variables quite well. The bottom line is you do need to think. This is especially true in the winter and even more so when you go into the 'wild'. I like to have a few options always and I do plan. Since I plan I can honestly say I've never had a problem ... not even close. As the charging network becomes more established ... which is happening really quickly now ... you won't even need to think soon. Electricity is everywhere!

JeffreyR | 5 novembre 2016

Read Doug_G's post on cold weather driving. He explains the reasons to not just pre-condition the interior, but also the battery.

EaglesPDX | 5 novembre 2016

@mp1156 "You can turn on the car to preheat every day in the winter - from the app on your phone."

That will be nice but probably have to rethink the process since the Tesla won't have to warm up. Instant on electric. I do the Remote Start to warm engine up to defrost so the car is drive able vs. for comfort. If there's been snow or freezing rain, I might turn give it five minutes to clean off the windows.

Of course, since it will be plugged in, I don't lose anything by setting it to warm up. A bit profligate on the power though, gotta remember even though I generate 120% from the house, the Tesla is going to purchased electric and even with the Blue Sky voluntary surcharge, there's a pollution price.

But main concern was how much of a load the battery heater would be on a depleted battery and it sounds like even for a sub-zero eight hours on the Hood Meadows parking lot, likely less than 10 miles of charge.