[Steverino]

Chicago has been in the eye of the Polar Vortex this week. Today is -23°F/-31°C. So, how does the Bolt do in this weather with:

• Snow tires,
• Snow on the roads
• Seat heater on max,
• Steering wheel heater on
• Max defrost
• Air set at 66°F on automatic

The battery range at full shows 132 miles after a full charge (no hilltop reserve for these days). So under some of the worst cold weather conditions, a 44% loss in range. That does not surprise me. With a 70 mile round trip commute, that's still plenty of range. But if we had a concern, there are a few pay charge stations at her work.

Side note: my wife noticed that while everyone else was in their idling car waiting for their engine to warm up and start providing warm air, she got in the Bolt, started up and drove away. The heated seats, wheel, and air system eliminate the need to wait in the parking lot. The Bolt has a nicer cabin heater than our Volt.

 

[Barry]

Great data point. Thanks for documenting and sharing. IMO, knowing what a realistic winter range will be in a given climate zone is an important factor in choosing a vehicle, and this information is not easy to come by for BEVs yet.

However, at -23F, I think I would be likely to shelter in place instead of driving.

 

[dannycamps]

Agreed - good data. Not really surprising and I think any EV would have the same rate of range loss with batteries being so cold. Wonder how a Leaf would fare (without an active thermal management system)

 

[Qinsp]

Perhaps consider moving to Deadhorse, Alaska where it's warmer?

 

[Steverino]

Both the Volt and the Bolt start out warm, from a heated garage, and the drive will keep the battery conditioned, but after that it's 8 hours parked in the cold. The battery has mass, but it will definitely cool during those 8 hours. Still, this is better than I expected for worst case scenario when I bought the Bolt. The great thing about having a Volt is it helps you understand how much range you need in a BEV to fit your needs. I knew the Bolt would work so had no qualms about it being more than adequate for winter range.

Without the Volt, I wonder if I would have bought the Bolt?

 

[Barry]

Yeah, this is why those BEVs that had ~85 miles of range are just out of the question for me. Maybe OK in the summer, but I need it year round. The new 200+ mile BEVs finally give the winter range, including safety margin, that many more people will be comfortable with.

 

[Don M]

Ultra cold weather range would not concern me at all - If it was 20 below outside, no way I would drive my BEV to work and let it sit and cold soak for 8 hours . . . . but then, there's also zero chance I would live anywhere that it ever gets to 20 below in the first place!

Don

 

[jbakerjonathan]

Ultra cold weather range would not concern me at all - If it was 20 below outside, no way I would drive my BEV to work and let it sit and cold soak for 8 hours . . . . but then, there's also zero chance I would live anywhere that it ever gets to 20 below in the first place!

Don

Wait for it, Don, it's coming down.....

 

[Steverino]

If it was 20 below outside, no way I would drive my BEV to work and let it sit and cold soak for 8 hours

Why not? That's not a problem as I have shown. 24 hours unplugged in that temp could be an issue, but not 8, 10, 12 hours.

 

[scottf200]

Why not? That's not a problem as I have shown. 24 hours unplugged in that temp could be an issue, but not 8, 10, 12 hours.

Unclear how you have shown or proven anything? That would include empirical data to show the battery temperature and at what temperature the error messages is activated. Perhaps you were only talking about range but not the more serious problems of error msgs saying the car needs to be towed/plugged in?

I'm not sure if it being colder than 0F or -10F or -20F (my gauge showed -25F today) changes how fast the battery gets 'too' cold as a linear or exponential change.

Does GM have deep cold testing data on the Bolt?

With our two Volts we preconditioned (started) them once in the middle of the day today. If you get the 'BATTERY TOO COLD, PLUG IN TO WARM' Volt msg you have to have the car towed after all (unless you are near where you can plug in or run a cord).

UPDATE:
On the Volt you can use MyGreenVolt to gather some empirical data on how the battery temp has changed every hour or so at given temps like today.

I wonder if the Bolt vs Volt PIDs/CAN data is identified in the same way.
MyGreenVolt: https://play.google.com/store/apps/details?id=com.MyGreenVolt&hl=en_US

 

[Tacoma]

Newton's law of cooling states that the rate of heat loss of a body is proportional to the difference in temperatures between the body and its surroundings.

Assuming that the ambient temperature is constant which it will not be in the real world, this law of cooling indicates that temperatures in the battery pack will drop quicker at first and then the rate of drop will slow down with time. During the day the ambient temperature was constantly increasing, therefore the Delta temperature between Ambient and the pack decreases, this also slows down the heat transfer rate.

Fyi, Today my pack was at 57°F around 7:45 AM and then by 11:30 AM the pack dropped to around 31°F.
Starting ambient temperature was -5°F, 11:30 AM ambient temperature was around 3°F.

 

[scottf200]

Bolt PIDs for empirical testing ---

Chevrolet Bolt OBD2 PIDs (creator Sean Graham).
https://docs.google.com/spreadsheets/d/1sY5n8WFu52U6a4_mg3MdcGcmDk3scAP8_muSy-BlXPc/edit?usp=sharing

 

[JD4JC]

Both the Volt and the Bolt start out warm, from a heated garage, and the drive will keep the battery conditioned, but after that it's 8 hours parked in the cold. The battery has mass, but it will definitely cool during those 8 hours. Still, this is better than I expected for worst case scenario when I bought the Bolt. The great thing about having a Volt is it helps you understand how much range you need in a BEV to fit your needs. I knew the Bolt would work so had no qualms about it being more than adequate for winter range.

Without the Volt, I wonder if I would have bought the Bolt?

Have just struck a deal on a 2019 Premier, MSRP -$4,000 and trading the 2017 in on it. Didn't make money on this trade, even with the generous CO tax and Fed credit, but am upgrading charging rate, rear seat heat, improved FM reception, ACC and other safety goodies. Agree that the Volt/Bolt combo is ideal!

Like you, we also a ICE gas hog pickup for hauling hay bales and such.

 

[Sean Nelson]

Does GM have deep cold testing data on the Bolt?

I've seen videos of GM technicians rolling the battery out of a large environmental chamber. I'm sure this is something they've tested quite thoroughly.

It's worth noting that the temperatures we are talking about affect the lead acid batteries in ICE vehicles in much the same way - their capacity is substantially reduced in very cold weather - and that occurs at the same time that the engine oil becomes more viscous and makes the engine harder to turn over. So a lot of ICE drivers like to find a place to plug in their block heaters, which is why a lot of parking lots in cold country are equipped with 120V AC outlets.

 

[scottf200]

I've seen videos of GM technicians rolling the battery out of a large environmental chamber. I'm sure this is something they've tested quite thoroughly.

It's worth noting that the temperatures we are talking about affect the lead acid batteries in ICE vehicles in much the same way - their capacity is substantially reduced in very cold weather - and that occurs at the same time that the engine oil becomes more viscous and makes the engine harder to turn over. So a lot of ICE drivers like to find a place to plug in their block heaters, which is why a lot of parking lots in cold country are equipped with 120V AC outlets.

I'm from a northern state so I understand block heaters and had them on my cars. Here in Chicagoland was -25F today. There are no cars with block heaters and no parking lots with 120V AC outlets for them.

I just questioned if there was any empirical data that the Bolt was perfectly fine in -25F weather sitting 8+ hrs in a parking lot. Maybe it is and, I would agree, that GM probably took it into account because the Bolt is sold in northern states and Canada.

For the Volt there were articles and testing shown on how it was tested in deep freeze boxes for XX hours. I didn't recall those for the Bolt. Likely they did based on past experiences with the Volt.

 

[saghost]

I'm from a northern state so I understand block heaters and had them on my cars. Here in Chicagoland was -25F today. There are no cars with block heaters and no parking lots with 120V AC outlets for them.

I just questioned if there was any empirical data that the Bolt was perfectly fine in -25F weather sitting 8+ hrs in a parking lot. Maybe it is and, I would agree, that GM probably took it into account because the Bolt is sold in northern states and Canada.

For the Volt there were articles and testing shown on how it was tested in deep freeze boxes for XX hours. I didn't recall those for the Bolt. Likely they did based on past experiences with the Volt.

Because of the unique development status of the Volt, GM showed the public all kinds of details that they normally don't. I'm assuming they consider the outcomes of their testing proprietary competitive information and that's why they generally don't publish them. Pity, because it'd be interesting to read those test reports.

 

[rmattila]

It is a shame that the BEV makers ignore the requests for a fuel burning heater. They would turn fuel to heat with 95-97 % efficiency which is higher than battery powered heat pump, and would help maintain the range in winter conditions.

 

[saghost]

It is a shame that the BEV makers ignore the requests for a fuel burning heater. They would turn fuel to heat with 95-97 % efficiency which is higher than battery powered heat pump, and would help maintain the range in winter conditions.

Higher than a heat pump?!?

Show your work, please - the typical heat pump moves around three times as much energy as it consumes, though that does decrease as it gets colder usually.

I have trouble believing any heat pump is getting down to 1:1, though - which is still better than 97%...

 

[rmattila]

Around -20 °C heat pumps tend to drop to 1:1. Factor in the charging and cold soak and you are around 70-80 %.

 

[FI Spyder]

I'm from a northern state so I understand block heaters and had them on my cars. Here in Chicagoland was -25F today. There are no cars with block heaters and no parking lots with 120V AC outlets for them.

I lived in Calgary which gets a lot of mild winter weather with it's Chinooks (compared to Chicago) but also gets -40 (stick C or F on that) with one night because of an unusual wind storm (cold weather is usually accompanied by still air there) where the wind chill went down to -80 one night. That being said all vehicles had block heaters (people born on the west Coast wanted to know what that plug sticking out of the grill was for) and many parking lots had AC outlets (but I'm sure not all). It's fine if it had to sit for a few hours while shopping but if it sat out overnight, there was no way you where going to work in your car the next day.