1. You will not get the nominal range in freezing weather even with zero accessory use. The tires have higher friction and the air resistance is greater due to higher air density.

2. The car 'learned' from the experience yesterday, so its projection today is more suitably pessimistic.

3. The included 120V charger is slooow. Like 48 hours to charge the car fully, but is limited to what comes out of a 15A 120V circuit. Buy a better charger, or get a 240V plug and adapter to double your charging speed.

 

if you want to charge the car you need a good high quality L2 charger - the L1 charger that comes with the car can only provide 960 or 1440 watts - if it was really cold last night some of the charging wattage while the car was plugged in was used to heat/condition the battery - not add range to the car.

Even in the best of circumstances it will take over 30 hours of L1 charging to return 50% of the total battery range to the Bolt - when it's cold and the car is attempting to keep itself warm and that slows the charging process.

also you need to tell us how much percentage battery you added, not range - the range estimate provided by the car varies widely and is dependent on recent driving history and observed usage - if you used a lot of power for heating the car's estimate of range will be impacted by your recent past history…

however the green bars on the left side of the dash display clearly indicate battery percentage with each alternating green bar representing 5% of total battery charge

driving an EV in the cold you will get lower range due to several factors:

1. the car works harder to drive at speed in denser air and crummy road conditions
2. heating the interior of the car takes a lot of power away from driving range and will lower the total distance you can drive on a full charge
3. the car also uses heating to heat/condition the battery which also lowers the range the car can be driven

Chevy provides an energy display on the main screen that will show you what percentage of battery is/was used for: driving, cabin heating, and battery conditioning

you will get less range in the winter than you will in spring/summer - by as much as 30%

the Bolt has a 60 kWh hour battery

in spring/summer with minimal AC use you can expect 5 - 10 km driven for each kWh consumed - meaning a 60 kWh Bolt could be driven 300-600 kilometers
in winter if you factor in 20% loss for winter conditions the effective range of the Bold could be as low as 240-480 KM driven - more if cold conditions are quite bad

the Bolt also has a charging AMP setting - it defaults to 8 amps for conservative safety concerns, there is an option for 12 amps - I recommend you make sure that your charge rate as set in the car is set to at least 12 amps that will help some what - until you can get an L2 240 volt charger installed.

Driving an electric car consumes kilowatt-hours of electricity - at 5 KM driven for each kilowatt hour consumed means you are consuming 0.200 kilowatt hours for each kilometer driven.

driving 5 kilometers (KM) = 1 kilowattHour (kWh)

a kilowatt = 1000 watts
charging the car for 1 hour at 1000 watts = 1 kilowatt-hour (kWh)

at 8 amps the L1 charger that came with the car provides 0.96 kw - plug the car in @ 8 amps for 1 hour will equal 0.96 kilowatt hours of charge - now there is some efficiently loss in the 6-10% range - so you get a bit less - lets just say at 8 amps best case you get 5 KM of range for each hour of charge

if you adjust the setting in the car to 12 amps you will get 1.440 kilowatts - so for each hour of charging you will get about 6-7 KM of range per hour of charge

the numbers above represent _BEST CASE_ when the car doesn't also have to use the power to condition the battery while charging - if the car is attempting to heat the battery during charging you will get less range per-hour of charge because the power is being used to heat the battery not add range to the car.

so with an L1 charger - in the spring during mild temperatures if you drive the car 120 KM @ 5 KM/kWh range - charging the car will require 120/5 = 24 kWh of battery
24 kWh @ 8 amps will take 25 hours - best case no heating required
24 kWh @ 12 amps will take 16 hours - best case no heating required

in the winter the 120 KM drive with a 20% loss factor due to road conditons, cabin heating, weather will require 29 kWh of charge
29 kWh @ 8 amps will take 30 hours of charging - probably more cause you'll lose some charging to "warm" the battery during charging
29 kWh @ 12 amps will take 21 hours of charging - probably more cause you'll lose some charging to "warm" the battery during charging

if heating is required it can take quite a bit longer…

the solution is a high quality L2 charger while requires a 240 volt circuit - the Bolt can charge at up to 32 amps at 240 volts - so let's say you you drive the same 120 KM @ 5 KM/kWh range - you will still need the same 24 kWh of charge - but with a 240 volt @ 32 amp charger - you are now charging the car at 7,680 watts - or 7.68 kiloWatts - doing that for 1 hour = 7.68 kWh

so 24 kWh / 7.68 = 3.125 hours to charge the car - and even if it needs to heat the battery worse case for 120 KM driven would be a 5 hour charge cycle over night.

the L1 charger that came with the car will be barely adequate to charge the car overnight in cold conditions if you drive more than 20-40 KM/day

you'll need to purchase and install a high quality L2 EVSE charger from Chevy/ClipperCreek/JuiceBox or others - they range in amps from 8-70 amps - the Bolt can use 32 at most - I would recommend installing a 32 amp charger as the cost difference for lower amp models is minimal and the real cost is the new electrical circuit/wire/labor for the install - don't cheap out on the charger because that's not your real cost.

if you can't or are unwilling to invest in an L2 charger I regret to inform you that the Bolt may have been a terrible purchase and not the right choice for you if you live in a cold climate.

http://www.chevybolt.org/forum/82-charging-batteries/7138-charging-opinions-long-time-ev-user.html
http://www.chevybolt.org/forum/82-c...orum/82-charging-batteries/7186-charger-math-skip-post-if-you-know-already.html

 

If you're looking for a new EVSE , the Clipper Creek EVSE is pretty popular on the forum.

 

Ignore the estimated range for now. Each green bar is worth 3 kWh. If you started with 20 bars/60 kWh, and you were driving that fast, with the heat on 70F (does it show C in Canada?), I would expect about 5.6km/kWh, or 16.8km/bar. The 120 volt charger, at the default 8 amp setting, is only putting 120v x 8a = 960 watts into the car. 9hr x .9kW =8.1kWh

I suspect the battery conditioned, for a half hour, once during the night. So yeah that's it.

 

http://www.chevybolt.org/forum/82-charging-batteries/19474-portable-charge-cord-came-bolt-240-a.html

 

Thank you all for your replies. I really appreciate your help.

 

Isn't it a 120V? I honestly don't know what I plugged in.
It was nighttime.

 

The stock charger can run on 120V or 240V, but the latter only with an adapter.

 

any updates - did you move to 12 amps? did it make a difference - do you have an L2 charger planned?

 

Where can I find information about how battery conditioning is implemented in the Bolt?

We bought a Bolt yesterday. We have owned an i3 for 10 months. For both cars, the critical information about battery conditioning is completely absent from the user manual and manufacturer web site, and of course the dealer people know less than nothing. The appalling lack of information I have to attribute to manufacturers' lack of motivation to sell EVs when they still aren't making much if any money doing so. Or maybe they have concluded that if a prospective customer is completely ignorant about battery issues, he or she will be more likely to buy an EV. They appear to be deliberately keeping us in the dark.

Thank heavens for forums!

I figured out I could set a timer in the i3 to do 30 minutes of preconditioning before a time I plan to leave; this is important in cold weather, especially below 20 deg F. This preconditioning both warms the battery and the cabin. My climate is not so hot that I need to cool the battery, at least so far, but I presume preconditioning would do that also if needed.

Reading Mr. O'Rourke's posts, it appears that the Bolt has some kind of regime to AUTOMATICALLY heat or cool the battery, if plugged in for charging.

What does the Bolt do automatically to maintain battery temperature in acceptable range if the car is NOT plugged in for charging?

Leaving the Bolt plugged in over night, how much power can I expect to use to heat or cool the battery, based on ambient temperatures? Are there any charts that show the relationship of temperature to battery conditioning power use?

(We'd like to think of the Bolt as a green machine, but having the car sit at home using energy to control battery temp knocks a nasty hole in that picture.)

Would the car use less power for battery conditioning if we left it unplugged?

Is there an ambient temperature range within which the car will NOT automatically heat or cool the battery while plugged in?

Are there any user settings or controls for battery conditioning?

Somewhere there is technical documentation about all of this. Does anyone know where I can get my hands on that?

Thanks!

 

The Bolt will automatically do Battery conditioning when necessary when unplugged, as long as the battery has a sufficient change, which apparently is 30% or greater. Chevy does recommend that the car be plugged in when temperatures are above 90F or below 32F, probably because battery conditioning is more likely to run in those situations, and more often when it does. Might as well preserve as much range as possible. It’s not require, of course. Anecdotal reports indicate that conditioning in the hot summer months consumed between 1% and 5% of total battery capacity. Unfortunately, the owners didn’t provide a lot of information as to how long the car was sitting in a hot parking lot, outside temp, how long conditioning ran, etc. Dunno what cold winter months will bring as I don’t live in a snowy environment. Our overnight temps tend to be in the high 30’s to mid 40’s, even in the dead of winter (benefits of living near the ocean in the SF Bay Area).

You can precondition the car, but you can’t set an automatic schedule, unfortunately. The act of preconditioning the cabin should also precondition the battery to a certain extent, as well. When I get up in the morning I turn on preconditioning before I hop in the shower. By the time I’m done with my shower, brushed teeth, have gotten dressed, etc, it’s been 20 minutes and the car is nice and toasty warm. I also have the car set to finish charging near around the time I get up, so the battery is nicely conditioned from getting charged recently.

The main reason I can see GM not wanting to push a lot of technical information about preconditioning and battery conditioning is information overload. They don’t want to give the impression that a consumer needs to be worried about all these issues if buying an EV. It’s simpler to make recommendations in the manual about best practices to use. They want the car to be seen as simple to operate as a traditional ICE vehicle. Plug the car in and let it do it’s th8ng to keep the battery happy. I too would like to know some of the nitty gritty details, but I understand why GM is reluctant to share them.

 

Thanks for response, Devbolt.

Yes, ignorance is bliss, I guess, at least in the showroom. I was generally aware when I bought the i3 that cold weather could be a problem, and temperature is indeed reflected in the car's estimate of range at full charge. But what I didn't realize was there is a threshold, somewhere between 15 and 20 deg F, below which the i3 becomes a real dog if it's not preconditioned. It goes, but it is EXTREMELY sluggish - to the point where I would say driving it could be hazardous. And the i3 does not automatically condition the battery when it's cold out. Something of a rude awakening.

So of course I now wonder whether such nasty surprises are waiting for us as we head into winter with the Bolt. Clearly the engineering decisions are different for each vehicle.

Not for nothing, the manufacturers should be forthcoming with some information, IMHO. Make us search for it, fine, but don't impose a freaking blackout. That's not good customer relations!

 

There are forum members here who have already experienced a winter with the car. No reports of degraded performance, just the expected range reduction.

 

physics

I should have paid more attention in Physics when talking about electricity and Amps.

 

Hello EV Forum,

I've had my Bolt for about 1 1/2 months. I took a wait and see approach to whether i'd purchase a L2 home charger. Here is my initial info on my cold weather charging experience.

I live in northern Vermont, a quite inhospitable place in the winter normally. I put about 15-20 miles on my Bolt daily. I charge it in my non-insulated garage. I charge at L1 EVSE 12 amp & have hill top reserve enabled. I also have it set to charge on "Off Peak" which is 9pm to 7am Mon-Fri and all day on weekends. I have normally had no issues with getting a full (hilltop reserve) recharge during those hours on my L1 charger.

However, old man winter has hit and we've had sustained temps between 10 to -10 degree f. It's about 15-20 degree f inside the garage. I have had issues getting much of a charge at all. I'm thinking with the temperature as low as it's been, that all the power supplied from the L1 EVSE is going straight to battery conditioning. When I look at the stats upon start up it says anywhere from 45-80% battery conditioning until I driver several miles. Then it lowers. I've gained only 5 miles of range in the last 10 hours of charging. I've switched the Time of Use (TOU) charging to "off peak" & "Mid Peak" to see if I can get more KW's during the warmer (still not so warm) daytime temps.

This has solidified my need for a L2 home charger. Have to put my order in to the big Jolly guy at the north pole.

 

Which L2 charger is Santa bringing you?