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Discussion Starter #1 (Edited)
I knew what I was getting into with regards to range and cold weather. Went from a Prius to a Gen II Volt and now the Bolt. Admittedly, the significant drop in range was more than expected but close to the lower end that was planned for. I'm lucky to have free level 2 (208V/20A) workplace charging so the drop in range doesn't really bother me.

I took two pics of two different drive cycles. One was when the bolt reached 60kWh and the other was when it reached 238 miles. At 60kWh, the Bolt traveled 141.6 miles. To travel 238 miles, it took the Bolt 90kWh.

This was driving with ambient temps around 20F, climate control set to 70, driving between 75-85 and dirty car. So it looks like worst case scenario is 2.3 - 2.6 miles per kilowatt. If I plan for 140 miles, knowing that slowing down will get more mileage and it should *never* leave me stranded.

I think some people who have never driven or don't know a lot about EV's may be a little upset if this scenario were to happen unexpectedly.
 

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Ha! I just created an account so I could relate similar experience.
I haven't had my Bolt long, but absolutely LOVE it. Luckily, I was expecting the drop in range also. It has been below 15F here for over 24 hours now, and my range says it is only 160. It doesn't hurt my feelings, but I imagine it could be quite a shock.
 

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I've got good news and bad news. The good news, here in the southwest I've seen zero drop in my EV range. The bad news, I'm still having to use Roundup on the weeds.
 

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This was driving with ambient temps around 20F, climate control set to 70, driving between 75-85 and dirty car. So it looks like worst case scenario is 2.3 - 2.6 miles per kilowatt. If I plan for 140 miles, knowing that slowing down will get more mileage and it should *never* leave me stranded.
Geez I thought my wife did the worst possible range last week at 252kms= 156 miles. See thread "Canadian Range Competition".

I'll have to send her out again now that I know she's got to go more like 130 km/hr (81 mph) instead of just 120. And I'll wait for a day with a stiff headwind. That should do the trick. Will let y'all know !
 

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I've just been reading the various threads regarding how the Bolt does in extreme cold weather. It appears that range takes a bit of a hit, but just how much seems to still be unanswered. Once I figure out how all of the gadgets work, I will try to keep track of this information. I'm hoping that the app will do most of the work for me. What information will be of most value to folks?

Here's a rundown of my situation:
I have a 2017 Bolt EV Premier edition (thank you tax rebates).
I live in NW Colorado with no garage, so there are going to be some pretty cold days/nights. Temps can & will get to below -30F at some point during the winter months. I do have a level 2 charger for home use, which will allow the car to draw as much power as she wants to be happy.
I will not be able to plug it in while I am at work. There is a public charger a block away from where I work that I can use for up to 4 hours at a time. I may take advantage of that free power on very cold days.
My daily commute is fairly short; approx. 20-25 miles round trip. The route is hilly, so it will be fun to see how much power I can get back from the regen.

I can't wait to start some winter testing.
 

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kWh's used to Precondition for 20 minutes unplugged @ -25 to -30F with windchill. (
-31C to -34C)
I know for a fact when I have it plugged in and i precondition the chrge goes from 0 to 7.8kwh on the graphs during the time i do it at 20F so its gotta be the same. this usage also seems to correlate to when i get into a cold car and dont PreC then at idle i see up to 8kwh on the gauge.

So 1/3rd of 7kwh is ~2.31kwh of usage
 

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I know for a fact when I have it plugged in and i precondition the chrge goes from 0 to 7.8kwh on the graphs during the time i do it at 20F so its gotta be the same. this usage also seems to correlate to when i get into a cold car and dont PreC then at idle i see up to 8kwh on the gauge.

So 1/3rd of 7kwh is ~2.31kwh of usage
Yes i.b. I think you're correct, IF the heater element & heated seat maxes out at about 7-8 for the entire 20 minutes. I'm still curious though, at superchill of -30F will heater draw even more and what about the seat will it get cranked up higher as well... thus is it going to be more than ~2.3 kWh. And will the rear defroster do anything different ? And is there any extra equipment we're not considering, kicking in a those superchill values.
 

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Just did a family trip to Grandma's house for the holiday (from home to NYC)....in the middle of an EPIC I-95 traffic jam and concurrent snowstorm. Pretty much a worst case outcome for a local drive or BEV. A family friend took 2.5 hours to get home from work at the same time...its about 15 miles for her.

Stats...went 115 miles in 5.5 hours (!) without stopping, starting about 90% SOC to about 20% SOC. Temps in upper 20s, blowing sticky wet snow. So 70% in 115 miles = 164 miles theoretical range or 2.73 mi/kWh.

We just put some XICE3's on the vehicle (used previously on our LEAF for 5000 miles or so), pressurized to about 41 psi (cold) for efficiency. HAD excellent traction entire way...no traction control cycles/skidding.

Car loaded with 4 adults/teens and a dog + their baggage.

We mostly ran the windshield defrost on 61°F or LO the whole time, and rear defrost as needed. MAX defrost for maybe 20 mins total as needed too. We spent a lot of time stopped in traffic, accessories were running 1 kW or so on the dash display.

Wipers got encrusted with ice, with a lot of chatter and hammering. Used blue stuff every few minutes due to continuous salt spray from road. When we did a driver change halfway through I removed the ice from the wiper blades manually. I saw a LOT of drivers on the side of the road cleaning their wipers....it was just that rare sort of snow consistency.

TL;DR The Bolt was a CHAMP.

Pulling into NYC I pointed out that the 2018 LEAF (the other car we considered) would have turtled at that point, as we crossed 40 kWh total usage.
 

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^ Drove home in the same crap yesterday on Long Island, took an hour and 10min for the normal 40min commute... was at 3.0 mi/kWh by the time I got home (only 23mi).

Ran out of wiper fluid just as I left work (of course!) so I drove home without it :mad:
 

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That's the other thing EV owners need to keep in mind- that normal 1hr commute will take 2hrs in snow... so you'll be using 2hrs worth of energy!
 

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kWh's used to Precondition for 20 minutes unplugged @ -25 to -30F with windchill. (
-31C to -34C)
OK... I don't really want to experience those conditions, but I'll do my best to gather that data when it happens. I literally have had this car for 1 day, so some info on how I would go about gathering this data would be greatly appreciated. :nerd:

What I can tell you from the brief experience I have about the car so far is that it is pretty dang awesome. The car was purchased in Aurora, Colorado which is south of Denver and had to be driven to Steamboat Springs. This was a distance of 171 miles over 3 mountain passes (one is over 11,000' in altitude) at night, departing in crazy Denver rush hour traffic, with the climate control set at 70F & the defroster running. Speeds were around 70mph on the highway outside of the city.
The car was fully charged from the dealer and made it the 171 miles with 22 miles remaining. Got some nice regen on the downhills.
 

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some info on how I would go about gathering this data would be greatly appreciated. :nerd:
With the Bolt “preconditioning” is synonymous with “remote start”. Refer to page 45 of Bolt EV Owners Manual for downloading myChevrolet app to your smartphone and syncing it to your Bolt. Page 343 has a list of functions available.

Preconditioning turns on the vehicle exterior lighting along with the heater (or a/c), heated seat and rear defroster. I think preconditioning shuts off automatically after 20 minutes.

I wondered how much energy it uses in very cold conditions during that time. One can “clock” such usage in kWh’s via the energy screen by recording the level of kWh’s in the battery at the beginning and again at the end of the procedure.
 

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Is he saying: battery conditioning takes place over 4 cycles in a 24 hour period ? And with ambient temp in the 20's F. It takes 1.3 - 1.4 kWh to do the job for each cycle ? So sitting in that condition Bolt is using 4*1.35= 5.4 kWh each day it sits ? And this occurs whether you're on a preconditioning cycle or not, and whether you're plugged in or not ? All this can't be can it (yikes..). I'd better buy a garage heater to put underneath my Bolt :eek:
 

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This line is the most relevant for driving in cold.

"The run time per cycle is definitely getting longer as it gets cooler and I have confirmed that the cycles consume the same energy from the battery when the car is unplugged."

This chart is from a LiFePO4 battery maker, not NMC like the Bolt. But it does suggest the effect of temperature on lithium batteries in general. if GM is trying to keep the traction battery above 40 F, you might still lose 10% of capacity at that temperature. I am sure they have looked at the break-even point, where heating the battery more uses as much capacity as you'd save by heating it with battery energy.


Celsius Fahrenheit Usable Capacity
60 140 103%
50 122 102%
40 104 100%
30 86 100%
20 68 98%
10 50 92%
0 32 83%
-10 14 80%
-20 -4 70%
-30 -22 60%
-40 -40 10%
-50 -58 0%
 

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Is he saying: battery conditioning takes place over 4 cycles in a 24 hour period ? And with ambient temp in the 20's F. It takes 1.3 - 1.4 kWh to do the job for each cycle ? So sitting in that condition Bolt is using 4*1.35= 5.4 kWh each day it sits ? And this occurs whether you're on a preconditioning cycle or not, and whether you're plugged in or not ? All this can't be can it (yikes..). I'd better buy a garage heater to put underneath my Bolt :eek:
I assume that GM is keeping the battery at 40 F. It takes what it takes. They do tell you to keep it plugged in. I am sure, if you leave it parked at the airport at 20 F for a week, they have it go into a hibernation phase, to prevent draining the battery completely. But don't expect your Bolt to have the same charge level, and normal performance, when you get off the plane from Bermuda.
 

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To: phidgt, Re: Next Assignment ! :laugh:

When it gets exceptionally cold like -25F or lower. And you're not using your Bolt for the next day or so. And if you've got plenty of charge in the battery.

Look at the kWh's at the beginning. Then look again after 24 hours. How many kWh's were used for battery conditioning ?
 

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I assume that GM is keeping the battery at 40 F. It takes what it takes. They do tell you to keep it plugged in. I am sure, if you leave it parked at the airport at 20 F for a week, they have it go into a hibernation phase, to prevent draining the battery completely. But don't expect your Bolt to have the same charge level, and normal performance, when you get off the plane from Bermuda.
That settles it. I'm taking a limo to the airport. Leaving my Bolt plugged in at home.
;)
 

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Is he saying: battery conditioning takes place over 4 cycles in a 24 hour period ? And with ambient temp in the 20's F. It takes 1.3 - 1.4 kWh to do the job for each cycle ? So sitting in that condition Bolt is using 4*1.35= 5.4 kWh each day it sits ? And this occurs whether you're on a preconditioning cycle or not, and whether you're plugged in or not ? All this can't be can it (yikes..). I'd better buy a garage heater to put underneath my Bolt :eek:
I went over this in my thread on battery logevity or it may have been the canadian winters one. I showed graphs from my level 2 evse.

battery conditioning takes place over 4 cycles in a 24 hour period ?

it may be more depending on temp and driving while sitting with the temps you indicated the cycle seems to be 1hr conditionin at approx 1.5kwh the 3 hours rest then 1 hour conditioning so basically a 4 hour cycle which would be 6 cyles per day. This is why i got my l2 evse and keep it plugged in all the time and using hilltop reserve. That way it stops at 89% and then uses evse to condition.

So sitting in that condition Bolt is using 4*1.35= 5.4 kWh each day it sits ?

I am not sure that this cycle it the exact same while sitting. I have had a discussion with a friend at GM speculating whether when its not plugged in it changes this schedule ot amount of energy used, but that needs to be proved and the only way i can figure is by % in the my chevy app.

I'd better buy a garage heater to put underneath my Bolt

Nah just get the l2 evse and plug it in, it'll take care of it for you. and if 90% is not good enough well charge to 100. But that another story.

See the graphs




There are 5 conditions one can see, first large hump to 7kwh is the top up charge then followed by the conditioning charge at about 19:00 with 4 more at 10am next day. My car sits outside. The ent at 13:00 it me preconditioning the car for 20 minutes before I leave.
 

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