Practical solutions for extending cold weather range

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New member
Feb 8, 2012
Moscow, Russia
Hi Everyone,

We currently ran few MIEVs as test vehicles in Moscow. Now it's around -20C and we have severe range decrease due to that. Maximum we get is 65km in very very ECO and heater almost not used.

The problem is the heater:
- it's all electric "boiler" type which means that it drains about 3.5 kWT of power so it takes about 4 hours to completely deplete the battery without driving
- car insulation (ours are 2011 MY) is insufficient because it simply does not hold the heat, i.e. it takes about 30 min to get to +15C in the car, highest temperature you can get when it's -22C outside is +22C after 4 hours :)

So we are looking for some cost efficient bolt on type of the solution in order to make winter life in I-MIEV less miserable. I'd be very much appreciated for any information sharing on this topic. We are thinking in the way of Webasto type diesel heater to incorporate it into the heating system. Which of course will make the car not zero emission for few month in a year but will definitely make it drivable in climate like ours.

BTW it holds to snow road surprisingly well despite RWD.

Cheers from Russia.
I have been thinking of putting my laptop PC in the car turn it on, close the lid, and use it as a heater. :idea: It has its own lithium ion batteries so its still as zero emission as the car is.
CHAdeMO, you are in a seriously cold environment! Nice to know that the iMiEV drives well in snow. Quite frankly, the present state-of-the art barely supports operation of an EV in that cold a climate (look at the lower temperature limits in the owners' manual). I'd be inclined to store the car for the winter (in a heated garage) and drive an ICE. A Webasto heater installation would require some imaginative venting and ducting, not to mention that it runs on diesel which sort of defeats the primary reason for an EV. Being in California, I'm clueless as to how to exist in your winter climate, and hope someone has some ideas. (jjlink, even if you filled up the car with laptops you'd still be frozen).
Good luck!
I agree that the heater is mediocre, which should've been a slam dunk in an EV, and I haven't completely figured out the remote preheat option. It seems to have a 'sweet spot' of around 15 minutes, and shut down in 30 minutes or so, after which the car cools down very quickly.
When not playing with the preheat, a 1500 watt 'ceramic' forced air heater set on the floorboards will get the car much toastier and 'heat soak' the interior before departure, which I've found really takes the load off during my 30 minute commute.
CHAdeMO said:
...The problem is the heater... drains about 3.5 kWT of power...
The heater is the great MPH equalizer:
Doubling the speed from say 30 to 60 MPH might half the Range from 6 miles/bar to 3 miles/bar, but that would half the heater energy for the same range.

If the heater is using 3.5 kW while the car is at 35 mph, which is about 5.5 kw and 6 miles/kWh, the car is using 9 kWh. 35miles/9kWh= 3.9 miles/kWh
If the car is at 50 mph, which is about 9 kw and 4.6 miles/kWh, the car + heater is using 12.5 kWh. 50 miles/12.5 kWh= 4 miles/kWh

If the heater is being used for the entire trip we could go 50 mph instead of 35 mph and use the same amount of energy.

If the car is at 60mph, which is about 15.3 kw and 3.9 miles/kWh, the car + heater is using 18.8 kWh. 60 miles/18.8 kWh= 3.2 miles/kWh

Do you have a way to preheat the battery? Derating the range by 1% per °C below 25°C gives a 45% reduction in range.
Ok we suppose to have a technical meeting to work out best solution next week with local importer of Mitsubishi Motors. They say there is no standard solution recommended by the vendor however they are offering several option which we will discuss looking at the car together with their service guys.

Stocking EV in winter is not our way. We are crazy Russians and we will be driving all winter 'round all of our EVs ;)

BTW I-MIEV is leading subcompact segment in terms of sales in numbers in Norway! :) Of course due to 0% registration tax which is 120% otherwise but still over there it's even colder than we have got.
I can't imagine using an EV with current technology in that kind of environment...but I wish you well.
Cold weather use is an issue here in northern New Mexico. Our winter nights routinely get down to 0F (-18C), and daytime winter highs are usually around 35F (+2C). We have a garage that we heat to 50F (+10C) in the winter, and are hoping that allows for a more complete charge. We can also pre-heat the car. I'm hoping that going from 50F to 65F inside the car can be accomplished in a few minutes of pre-heating.

CHAdeMO: have you tried garaging your cars in the winter? If so, does that make a difference?
First, I preheat while it's plugged in and use the seat heater. Then I tried this "NanoSafeguard" stuff that I found on the web to help with defrosting. Sounds like a gimmick but it helps keep he windows defogged. So far it has worked very good in Seattle's mild wheather. I usually drop one bar commuting 6 miles to work. This morning I didn't preheat so I used the heater intermittently and used two bars getting work.
I tell everyone that you can be cold and drive far, or be warm and drive short. The seat heater uses the auxiliary battery!
Our winter's in New Zealand are not as cold with about -4 being the usual where I live. As our 2012 model year NZ specification car does not have the remote start or preheat option found in the USA 2012 models, we had to come up with a solution for the iMiEV for Winter motoring as we park the car outside in the drive even in Winter as the garage is full already.

The solution we came up with is a small electric fan heater with thermal cut out switch, which will turn off the heater if it gets too hot, and a thermostat on the heater that cycles the heater on and off to keep a desired temperture.

This means the car can be on a seperate power circuit from the heater, and so use the ful circuit load for the car charging if need be, and the heater has it's own 10 amp 230 volt 50 Hz circuit for heating.

The car at our tempertures should reach a nice 22 degrees C from - 4 degrees C in about 15 minutes.

The important points are :

Very much ensure the heater is not pointed at a place which would get too hot and catch fire, and ensure nothing will fall onto the heater such as jackets or coats or the homework paper.!.

For extra safety, we turn the heater to low output so the heater takes longer to get the car to temperture, but is not so hot that it is so important to be extra careful about the direction of heat flow.

Put a timer on it so that it resets after 30 mins so the heater isn't on unattended for very long.

The top of the dash but facing into the car should work well on low, though a heatproof silocine rubber mat underneath the fan heater is a good idea for heat and vibration protection for the dash.

Not as cool or easy as a remote start or timer heater built in, but should work if that option is not on your car. :idea:

That solves the preheat option, but the car soon cools off when driving, so insulation is a must, the door panels have a bit of space behind them and the floor pan underneath the car can be fitted with a sheet of insulation with plastic wrapping for water and humidity sealing, insulation like fiberglass batts or similar. Wrapped Sleeping bag insulation works too.

The Roof panel can be insulated too, but would be fiddley to do. The boot panel and side pockets would also benefit from this and would keep the car a bit cooler on hot days too.

I covered the iMIEV's radiator grill to protect the radiator against stone chips while road testing when I didn't have the aircon on, and this might help reduce heat loss from the cold outside air hitting the firewall but it would be best to check that doesn't affect the battery cooling when working the motor hard or while charging.

But yes, I think the diesel heater like that used on boats or Campervans woud be also good, but might be hard to vent , perhaps placed under the front hood ?.

Another thought..You know how the heated seats help for warmth, and using the same idea, what about 12 volt electric blankets on the roof panel or behind it, it would give off a heat similar feeling to an overhead sun maybe.

The 12 volt battery can be supplemented with an additional one in the boot perhaps or the front one could be replaced with a larger one. Any 12 volt usage is charged from the iMiEV main battery so without an extra battery, the 12 volt usage would be lowering the main battery too, and for every 12 volt 100 amp hour battery added, you get the equivalent of 1,200 watts though at say less than 50 % discharge, that would be only 500 watts, but that is enough for a 120 watt electric blanket on full for 4 hours !

Also we are thinking of putting a 140 watt solar panel, the flat flexible type, on the car for topping up the 12 volt back up battery, so we can leave a radio on while working or to cool the car on fan only while having a break on the side of the road.
How about this as a way to extend cold weather range?
I know that this discussion is a little out of season, but I have serious concerns with the Range and Comfort level for driving the Miev in extreme cold.
Specifically the Driving Range and the cabin comfort heating while driving.
Not concerned about the departure point or the destination as there are charging/ heating facilities at both ends.

We are located in Quebec, Canada and also experience -25C to -35C ( -13F to -31F) temperatures, sometimes for up to a week at a time. -15C to -20c are very common winter temperatures.

CHAdeMO I was wondering if you or any other members have come up with any solutions?

I often Mcgivir things to try and get a solution
For those few extreme conditions I have been considering using something like this,

It would be mounted on a stable platform with a protective perimeter wire fence,
in the storage trunk area with one rear seat folded down for air circulation

I have one of those small propane bottle heaters exactly like the one in your link. It puts out WAY too much heat for the interior cabin of an i, and it's difficult to modulate the heat. Also burning propane gives off CO2 and moisture, so interior climate could be a problem. I would seriously hesitate to drive a car with windows up for any significant distance with a propane heater. They have an auto-shutoff when oxygen levels get too low, but human beings also have an auto-shutoff when oxygen levels get too low.

Did you think about pre-heating your cabin before unplugging? Or even using a small electric heater in the cabin and unplugging it before departing? The biggest issue in heating or air conditioning is making the initial temperature change up or down. Once you're at an appropriate interior temp, it does not take much power to keep that temp stable.
Thanks for sharing your experience with this model heater.
They do advertise the auto shut off for Tip Over & Low Oxygen Sensor. I think I should give it some consideration to size up (BTU) an appropriate size heater- maybe get a smaller unit – but I would rather have too much than not enough & have a heater out put control - however I could turn it off or crack a window if things get too hot.

I don’t know if you have experienced these extreme cold driving temperatures - Our Honda Fit would need to pre-warm (Autostart twice) 15 minutes each and then we could start driving, With the heater up on full, rear side windows would stay frozen for up to an hour, then the things would just start to get comfortable.
Generally, in these parts, these extreme temperatures make up 7-12 days of the year at most.
I would garage the Miev overnight on these days.
It's the siting at the train station (Pugged in) 12 hours ,at these temps that could make for a cold ride home.
sandange said:
We are located in Quebec, Canada and also experience -25C to -35C ( -13F to -31F) temperatures, sometimes for up to a week at a time. -15C to -20c are very common winter temperatures.

Ok, that beats Albany, NY. I've been thinking about this shortcoming of the i MiEV for a while because I hate the cold. These items would seem to help with your personal comfort:

With a heated jacket and the heated seat - which warms up pretty quickly - you should be able to take some of the bite out of those crazy cold temperatures. Of course there would still be the issue of the cold cabin and condensation on the windows. If you're plugging in at the train station you can set the heater to come on at a specific time, but I think there's a short time limit on how long it will run so you need to plan carefully. As far as propane heaters, boy that's risky. Driving at night, you're already tired, a few wiffs of carbon monoxide might be all it takes.

So maybe you and BillThompsonMIEV should think about house-sharing. He lives with you in Quebec in the summer, you live with him in San Antonio in the winter. San Antonio is beautiful in the winter. :D

I have a feeling we'll be discussing this much more come November. Good luck.

As an all weather motorcyclist, the way we keep warm is using heated gear! This stuff is toasty and doesn't take too much juice either because motorcycles don't have a lot of spare wattage or batteries.

I'm in the same boat during the winter time here in the Niagara region. I have the heated seat and the cold weather package as all i MiEV's do in Canada. But, the heater really cuts down on the range. I plan to garage my car in the winter, time the recharge to end just before leaving in the morning (warms the bat pack), preheat the interior and use my heated jacket liner from my motorcycle for heat. Still waiting to see if the garage will let me use their outlets so I can trickle charge and preheat for the ride home.}&utm_term={keyword}&segment=badger

Glad to hear the car does well in the winter time. Probably works like the old Volkswagen Beetles did.
I just read up in the Tech posting on the Miev Climate control system

Great Information! Good to see that they are looking to evolve & improve the system.

However I still think I need to find a winter cabin heating solution for our extreme weather conditions

Mlucas – Good old VW Beetle - fond memories – had build a VW Dune Buggy – But that’s another lifetime ago

Thanks all for your heating accessories suggestions. I’m a seasoned long distance motorcycle rider and aware of the option for cold weather situations. We have enjoyed over 60,000 km on our present motorcycle, which happens to be our only other mode of transportation.

To Make a short story Long

Winter Commute
Let me paint a very possible scenario for my personal commuting situation. Not worst case

Car garaged 10C (50F) over night & fully charged
Leave the house 5:30 am – temps are –33 C (-27.5 F coldest time of day)

Weather is over cast - light blowing snow
Road conditions - snow covered 2”- 3”, hilly back roads are drivable but slippery & you need to drive slower
Your commute of 20 km (12.5 miles) takes 35 minutes with the defrost/heater/wipers on full

Park at train station and plug in level 2 charging station, go to work

You’re gone all day from 6:am to 7:00 pm
During the day, temps warmed up to –25C (-13F) but by 7:00 pm cooled back down to – 28C (-18.8F) & dropping.

Here are some points that are not clear to me

Car battery should be fully charged – if there hasn’t been a major power failure during the day
Or will it?

1) Does the extreme cold prevent the battery from getting fully charged as it draws power to keep itself from freezing?

2) Does using the remote to program the preheating option keep the battery from fully charging by drawing power?

One question I have for Hydro Quebec “Circuit Electrique” Charging station service (pay, card swipe).
Need to investigate this one
1) If there has been any power failure during the day, does the Charging Station resume charging when the power goes back on?

Scenario continued

It’s been snowing on & of all day and there has been some significant accumulation. This has made the hilly back roads too risky.
Now you need to take the highway that has been ploughed, but down to 1 lane & slow moving
This adds 6 km (3.73 miles) & 45 minutes
To get home you have a total of 26 km (16 miles) & 1:15 hrs commute with the defrost/heater/wipers on full to get home.

At his point things could be getting close to their maximum limits.
There fore my search to get a back up heating system to conserve the drive battery

Still looking for options
Sandage - you are definitely going to test this i MiEV's cold weather capabilities to the maximum. We don't get nearly that bad here in the Niagara region. Last winter we didn't have hardly any snow at all. Our averages are around -10 to 0 in the winter time sometimes dipping lower.

I would definitely read up about the Cold Weather Package in your owners manual. I posted it here: It mentions how the system works and the cold weather charging restrictions.

As far as your questions go, this is what I know:
1.) The additional systems that run while the car is charging are run from the supply current not from the car battery. Like the A/C for pre-cool is run from your house current not the battery pack. The 'fuel gauge' will show full when you get in the car.
2.) No, same thing as #1. You'll get a full charge. The remote only works within range of the car, its not like the PhoneApps that the Volt and the Leaf have where you can schedule a preheat. You have to send your car the signal to preheat within 100m or 300 feet of the car, so you won't be able to preheat until you are back at the station. If you can park where you can see your car from the train, you might be able to signal it to preheat so it will be somewhat warm by the time you walk to the car.

For question #1 on the Circuit Electrique.
That I can't answer but the way the home EVSEs work, is they will send the car a signal that its ready to send the load again and the onboard charger will resume charging.
MLucas Thanks for your response & link & info,

Congrats on your new Miev, By the way, I see we both own the same model (Canadian Base Model) and
We both have the fastest color too.

The question about the Hydro Quebec "Circuit Electrique" Charge stations -
I should of made clearer as.....

If I had swiped my pay card & were charging,
Shortly after, there was a power failure for 5 seconds or more.- but now I've left to go to work.

When the power returns, would it continue charging or
would the charger think the session was over and require another swipe.

I've sent an email to them regarding this, and hope to get an answer soon.
Good question about the charger. I haven't used a public charge station yet, as there basically arent' any around here. The Niagara region has yet to come into the 21st Century.

We have the Stealth i MiEV in bad-azz black. I got my windows tinted, too. It looks really good and saves me from having to run the A/C a lot.

These Canadian base models are really nice and well equipped compared to the US base model. I kind of like the way they are setup because it has everything I wanted without having to pay the premium price to get something I really wanted to have. All I really cared about was the CHaDEMO port (not sure why when there aren't any public charge stations here - maybe for future), the fog lights, and the cold weather package.

We'll have to compare notes this coming winter and see how the i MiEVs do. I have a long commute that I'm curious to know how the car will do.