Disappointed with cold-soak battery range (no garage) Or is it just me?

[gregtopf]

I've had my MS 75D for a few months. Got it late summer. I have roughly a 15 mile commute (each way) to work. During the summer, I'd have to charge up roughly 1-2x per week depending on what errands I ran outside of work. Wasn't a big deal. Now that it's been getting cold-ish (we have had a few nights below freezing), I'm seeing a drastic change in the battery performance. I'm having to charge close to double before. Minimum 3x per week charging to 90%.

I'm pretty sure my issue is that I don't have a garage, so my car sits outside. I get the dashed yellow lines under the regen side of the dial for almost the entire drive in, and my kwh usage has gone from ~300 to ~450.

Thoughts on this? I expected a change in performance in the cold, but it concerns me that it's been this significant so far and we haven't hit the really cold winter weather yet.

 

[Xenius]

Cold weather is certainly a higher usage. The other issue is that your commute is pretty short and so you're spending a lot of energy warming up the battery pack to then let it sit again while you're at work.

You can adjust this by turning range mode "on" if you want, but since you're not warming the battery you'll also be stuck with limited regen. Really no matter what way you cut it, you're going to need more energy when the weather is colder, that's pretty much just how it is.

The effect wouldn't be quite as pronounced on longer trips.

 

[Siggy101]

Sadly, without a garage, this is not unusual behaviour for an electric car in winter.
Forgive me if I am saying something that you already know but just in case...

One thing that can make a big difference is wind.
When the car is parked in a windy location, any heat that the car puts into the battery (through charging, discharging or BMS heater) is stripped away faster than if it were in shelter and the BMS has to use power from the battery itself to replace that heat. This then reflects as vampire drain (lost miles when not being driven) as well as a very cold battery. Are you able to build any sort of shelter around where you park your car (log pile, lean-to etc)? Alternatively, can you park on the leeward side of a building for example? If you can retain some warmth in the battery, you will use less power to warm it when you drive.
Any shelter will help but sadly, you are always going to see reduced range in the cold.

Also, is the car plugged in when not in use? If you do plug it in when parked, it will use shore power to warm the battery (and the cabin for that matter) when you precondition the car (via the app or automatic preconditioning). If it was not preconditioned whilst plugged in, the first thing that happens when you drive is that the BMS tries it's best to warm the battery to operating temperature. This results in that higher Wh/M that you are seeing on your relatively short commute. A warmed battery will still show higher consumption in winter but not nearly as much as a cold soaked one.
Try using range mode. Some people say that it disables the battery heater. YMMV

Last tip: Use your seat heaters instead of cabin heater when possible. The cabin heater uses something like 6kW. The seat heaters are under 1kW I think. It's not gonna make a huge difference but it does explain a portion of your usage.

 

[bambam4171]

Last tip: Use your seat heaters instead of cabin heater when possible. The cabin heater uses something like 6kW. The seat heaters are under 1kW I think. It's not gonna make a huge difference but it does explain a portion of your usage.

Seat heater are usually below 60w, I guess he is driving alone. If he is then there is a 100 fold energy difference between heating the cabin and heating a seat.

 

[Siggy101]

Yeah, thinking about it, you are right BamBam.
A 1kW heater would be rather interesting to sit on!!!!

 

[Xenius]

Yeah, thinking about it, you are right BamBam.
A 1kW heater would be rather interesting to sit on!!!!

Especially considering on the highest setting those seat heaters get somewhat uncomfortable (at least to me).

 

[Brian-MS90D]

@gregtopf , out of curiosity, what is motivating you to minimize the frequency with which you plug in over night? I know you do not have a garage, but are you also not able to charge in your parking spot?

I can also confirm what others have said that what you are observing is normal. There is a lot written on this forum about cold soaked batteries. This is a great post:
Cold Weather Driving

 

[gregtopf]

Part of my Tesla thinking was to even minimize my home electric usage during charging since I have good destination charging at work.
My electric isn't super cheap, so my thinking was just use it as little as possible. So that's the only reason. I had a bit of a pie in the sky vision to charge when needed at work since it's zero cost and top up during the weekend.

I can't imagine what will happen when the snow flies and the car is parked on top of snowy driveway!

I'm not complaining, I read up quite a bit beforehand. I'm just more stating that I'm surprised to really see the difference firsthand.

I do use the seat heater by the way...that warms me from the bottom up, and my morning coffee warms me from the inside out

 

[ucmndd]

Those 15 mile trips from a completely cold battery are kinda the worst case scenario as far as energy consumption goes.

On your charging days, try and time your charging to complete within 30 minutes or so of your departure, so you’ll leave with a warm battery. That will make a big difference.

 

[Skotty]

Cold soaked is terrible for supercharging also. Just a word of caution and advice; if on trips in the cold, try to charge overnight or at night, not in the morning.

 

[mspohr]

Part of my Tesla thinking was to even minimize my home electric usage during charging since I have good destination charging at work.
My electric isn't super cheap, so my thinking was just use it as little as possible. So that's the only reason. I had a bit of a pie in the sky vision to charge when needed at work since it's zero cost and top up during the weekend.

I can't imagine what will happen when the snow flies and the car is parked on top of snowy driveway!

I'm not complaining, I read up quite a bit beforehand. I'm just more stating that I'm surprised to really see the difference firsthand.

I do use the seat heater by the way...that warms me from the bottom up, and my morning coffee warms me from the inside out

So, why don't you just charge at work every day?
Are you saying that you can't make it the 15 miles to work?
Battery range decreases until it warms up and that may take more than 15 miles in cold weather but I don't see how this could be a problem if you charge at work each day.

 

[Qbenjamin]

Part of my Tesla thinking was to even minimize my home electric usage during charging since I have good destination charging at work.
My electric isn't super cheap, so my thinking was just use it as little as possible. So that's the only reason. I had a bit of a pie in the sky vision to charge when needed at work since it's zero cost and top up during the weekend.

I can't imagine what will happen when the snow flies and the car is parked on top of snowy driveway!

I'm not complaining, I read up quite a bit beforehand. I'm just more stating that I'm surprised to really see the difference firsthand.

I do use the seat heater by the way...that warms me from the bottom up, and my morning coffee warms me from the inside out

I don't understand your logic here on trying to save money by using chargers not at home. I used to commute 50 miles daily, charged EVERY night back to 90%, and my electric bill only went up by $40 per month. It's one thing to be frugal, it's another to "over-burden" yourself for a nominal savings...

 

[ItsNotAboutTheMoney]

I've had my MS 75D for a few months. Got it late summer. I have roughly a 15 mile commute (each way) to work. During the summer, I'd have to charge up roughly 1-2x per week depending on what errands I ran outside of work. Wasn't a big deal. Now that it's been getting cold-ish (we have had a few nights below freezing), I'm seeing a drastic change in the battery performance. I'm having to charge close to double before. Minimum 3x per week charging to 90%.

I'm pretty sure my issue is that I don't have a garage, so my car sits outside. I get the dashed yellow lines under the regen side of the dial for almost the entire drive in, and my kwh usage has gone from ~300 to ~450.

Thoughts on this? I expected a change in performance in the cold, but it concerns me that it's been this significant so far and we haven't hit the really cold winter weather yet.

Cold weather hurts. You're heating the car and heating the pack. It doesn't help that you don't have a garage.

Also, check your tire pressures. If you haven't adjusted them for the colder weather you'll be seeing much greater rolling resistance.

 

[ItsNotAboutTheMoney]

Part of my Tesla thinking was to even minimize my home electric usage during charging since I have good destination charging at work.
My electric isn't super cheap, so my thinking was just use it as little as possible. So that's the only reason. I had a bit of a pie in the sky vision to charge when needed at work since it's zero cost and top up during the weekend.

I can't imagine what will happen when the snow flies and the car is parked on top of snowy driveway!

I'm not complaining, I read up quite a bit beforehand. I'm just more stating that I'm surprised to really see the difference firsthand.

I do use the seat heater by the way...that warms me from the bottom up, and my morning coffee warms me from the inside out

If you can charge at work, when do you start charging and how fast is it? Ideally you want the car to be charged just as you leave so the battery conditioning will have it be warm.

 

[YauKwan]

I've had my MS 75D for a few months. Got it late summer. I have roughly a 15 mile commute (each way) to work. During the summer, I'd have to charge up roughly 1-2x per week depending on what errands I ran outside of work. Wasn't a big deal. Now that it's been getting cold-ish (we have had a few nights below freezing), I'm seeing a drastic change in the battery performance. I'm having to charge close to double before. Minimum 3x per week charging to 90%.

I'm pretty sure my issue is that I don't have a garage, so my car sits outside. I get the dashed yellow lines under the regen side of the dial for almost the entire drive in, and my kwh usage has gone from ~300 to ~450.

Thoughts on this? I expected a change in performance in the cold, but it concerns me that it's been this significant so far and we haven't hit the really cold winter weather yet.

hey, im closed to you in Dumont NJ, Car also is outside and getting the same experience as you. I thought about buying a car port thing to at least keep the car covered, but not sure if my town allows it.

two things you can do.

1. Call pseg, and change to Time of Use Billing. Its more expensive electricity in the day when im at work, cheaper in the PM when im charging my car. This billing rate may not work for you depending on what your morning usage is. Basically double cost in the morning and 1/2 cost at night.

2. Plug in every night but adjust your amp so that you can charge your car every night, and have it finish right before you leave for work. This will keep your battery warm for the commute. Currently mine is set to 16 amp at 220 and that is enough to get me back to 90% by the morning. Doing that also keeps my UMC cooler vs charging at 40 amps.

 

[zer0cool]

Cold impact on EV is HUGE. I live in South Carolina and I have seen power usage in the 470's on the coldest days while commuting. I am sure my coldest days are much warmer than yours; and I average 270s in the summer. I also see those yellow dotted lines all the time when driving back home since car is parked in high rise garage during the day.

It's all very normal. Basically just think of range being almost halved during the winter...

 

[DFibRL8R]

As others have said, keep it plugged in overnight.

Even if you want to do most of your charging at work, 30 minutes before you leave for a trip, consider using the app to add some last minute charge (and if you want prewarm the cabin). This will condition/warm the battery immediately prior to your drive and will extend the range.

 

[alehbaba]

its the nature of the beast i guess. Even super hot climates may also do the same to battery range

 

[alehbaba]

its the nature of the beast i guess. Even super hot climates may also do the same to battery range

I cant imagine leaving a 100k car outside in the environments in colorado. I mean sure if you go to work and there is no parking structure you have to park it outside while you work for 6-12 hrs i guess but at night...no way can i leave it outside with the wierd weather we get from snow to hail to vandals even

 

[mspohr]

I cant imagine leaving a 100k car outside in the environments in colorado. I mean sure if you go to work and there is no parking structure you have to park it outside while you work for 6-12 hrs i guess but at night...no way can i leave it outside with the wierd weather we get from snow to hail to vandals even

I left my Tesla outside the first winter. Live in the Sierras. It got wet and snow and iced and cold but it's just a car and it survived just fine. No vandals in my neighborhood.