Gorfllub
Posts: 75
Joined: Sat Aug 04, 2018 6:08 pm

Ultra cold weather range

Fri Aug 31, 2018 8:18 am

Winter is coming. It's already dropping to 0 degrees (c) here at nights. And for a good chunk of the season, we will sit between -20 / -25 with some days as low as -40 and sometimes a solid week of -30

Currently live 15km from work. No problem with Level 2 charging there. No L2 at home yet but currently I don't need it. (1000km of driving so far, only 3 L1 charges at home, and those were mainly due to "range testing" on the weekends.

But we are looking at potentially moving 60km out of town. Highways with 100kmh limit. Some back roads can be taken with lower limits. Road is a bit hilly. But a net zero altitude change.

I will be installing the diesel heater, so that will have negligible reduction in range. Headlights will need to be on all the time as when I leave for work, its dark and when I return its also dark.


Oh, and no garage now or later so the car will be always outdoors.


Looking for comments from anyone with similar circumstances. Do you think 60km can be done @ 90kmh in -30 degrees? Blower motor, lights, heated seat on.


Currently in 20c degree weather, my RR averages around 92 km. My all time high has only been 108 and a low of about 85.


Thoughts anyone?

jray3
Posts: 1662
Joined: Tue Dec 06, 2011 1:05 am
Location: Tacoma area, WA
Contact: Website

Re: Ultra cold weather range

Fri Aug 31, 2018 10:55 am

Many charts are available online showing LiFePO4 discharge curves at various temperatures, showing between 20% and 60% capacity loss at super low temperatures. I think that your range will be impacted by at least 40% at -30 Celcius.
Heating the battery up to room temperature would be the best guarantor of capacity. I don't know how to hack the OEM battery heaters, but have considered both radiant pads to park over and stick-on mats such as are used for engine oil pan heating.

With all the windscreen and snow clearing issues, I'd sure seek a heated home for the car if I were using it daily in those conditions. I realize that folks all over the great white north cope with outdoor autos all winter long, but it would seem a good investment of labor to erect a quonset hut or other simple shelter. I'm looking forward to Ben Nelson's reports this winter on the performance of his active/passive solar garage. https://300mpg.org/bens-solar-garage/
2012 i-SE "MR BEAN" 105,400 miles
2000 Mazda Miata EV, 78 kW, 17 kWh
1983 Grumman Kurbwatt EV,170 kW, 32 kWh
1983 Mazda RX-7 EV 43 kW 10 kWh
1971 "Karmann Eclectric" EV 240 kW 19 kWh
1965 Karmann Ghia Cabriolet

PV1
Site Moderator
Posts: 2994
Joined: Fri Apr 27, 2012 4:22 pm
Location: Pittsburgh, PA
Contact: Website

Re: Ultra cold weather range

Fri Aug 31, 2018 11:31 am

Brr. Since you mentioned a diesel heater, life will be a lot easier with one of those, especially with workplace charging. That said, with -10F and the stock heater on MAX, my worst range was 40 miles/64 km.

At temperatures that low, you'll need to keep the battery warm. With a cold battery, you'll have an immediate 10-15% hit on range due to weak regen, and if it is too cold, won't charge. I definitely recommend using the slowest charge rate that time allows, and starting charge immediately after driving. Besides preventing lithium plating in the cells, a slow charge keeps the cells active and therefore warmer.

The often-cited battery thermal mod is removing a servo on the ductwork leading to the battery. This is found in the Driver's side footwell behind the USB port, at least on NA models.

https://www.dropbox.com/s/t5jezlryoo1j7 ... 8.jpg?dl=0

Unplugging and removing this servo allows one to flip the damper and send heated or cooled air to the battery at any time. Just make sure that the damper is to the battery before charging. I leave mine there full-time so I don't have to worry about it. To send air to the battery, just set the airflow towards the floor (feet) position. If you're sending air to the battery, I recommend using fresh air (recirculator light off). Besides putting a negative air pressure in the cabin, sending warm, moist air into a cold battery can cause condensation inside the pack, which is not a good thing with circuit boards being in the pack.
:idea: :idea: :idea: :!: :!:

Dropbox maintenance in progress. If any of my links aren't working after November 17, please PM me and let me know which one isn't working.

Thanks.

Gorfllub
Posts: 75
Joined: Sat Aug 04, 2018 6:08 pm

Re: Ultra cold weather range

Sat Sep 01, 2018 7:48 pm

All good info, thabks.

We aren't allowed any type of temporary shelters or garages, so I would actually have to permit one.

And with a potential move coming up, it may be a lot of effort for only a couple of months of usage.

I think I will try and put on as large of a fuel tank I can fit and use the diesel heater on a timer in the really cold nights. Then with the flap mod it can keep the battery temps up a bit

sandange
Posts: 907
Joined: Thu Jul 05, 2012 2:21 am
Location: Quebec, Canada
Contact: Website

Re: Ultra cold weather range

Sun Sep 02, 2018 6:08 am

Hello Gorfllub.
We have a 2014 north American i Miev with over
170,000 km, (105,500 miles)
Where are you located and what year & Model do you have?

We live North of Montreal, Quebec, Canada and have similar weather conditions.
I installed a diesel heater before our 1st winter and highly recommend one.
It is a major improvement in the winter driving experience of the i Miev.
Some liquid diesel heaters can be ordered with a remote control.

We live in ski country and have to deal with lots of snow & many hills.
Your 60 km commute should be a comfortable drive in the winter with using the diesel heater and the seat heaters.

Try to time your charging to end about 1/2 an hour before your departure in the morning
to have the battery pre-warmed.

When in doubt slow down your speed (85-90) kmph), pushing that cold dense air uses a lot more energy.
Tesla Model 3 SR+, 2019
Previous EVs
Puey Bluey 2014 Miev
200,000 km , 124.000 miles.
Blackie - 2012 ES Miev 2 years - 67,000 km / (41,630 miles)
http://thecordstead.blogspot.ca/

Gorfllub
Posts: 75
Joined: Sat Aug 04, 2018 6:08 pm

Re: Ultra cold weather range

Mon Sep 03, 2018 8:42 pm

Awesome. That's encouraging.

I'm in Red Deer, Alberta.


2012 es with QC


I'll be able to trigger my diesel heater from my alarm remote or cell app.

The big thing for me is it's going to be parked outside this winter.

sandange
Posts: 907
Joined: Thu Jul 05, 2012 2:21 am
Location: Quebec, Canada
Contact: Website

Re: Ultra cold weather range

Tue Sep 04, 2018 3:15 am

I parked my 2012 - i Miev outside (2 winters) so it did get cold soaked overnight .
When it was colder than -20 C I left it plugged in all night and would do
two 1/.2 hr pre-heat sessions on defrost just before my departure.
(I also left the seat heaters on for the preheating)
Good luck with the diesel heater install.
Tesla Model 3 SR+, 2019
Previous EVs
Puey Bluey 2014 Miev
200,000 km , 124.000 miles.
Blackie - 2012 ES Miev 2 years - 67,000 km / (41,630 miles)
http://thecordstead.blogspot.ca/

Gorfllub
Posts: 75
Joined: Sat Aug 04, 2018 6:08 pm

Re: Ultra cold weather range

Mon Sep 10, 2018 8:26 am

Sandange,

Absolutely awesome place you have out there!

sandange
Posts: 907
Joined: Thu Jul 05, 2012 2:21 am
Location: Quebec, Canada
Contact: Website

Re: Ultra cold weather range

Wed Sep 12, 2018 7:54 am

Thanks
:D
That's our other passion (Alternative home building) and retirement home.
We offer tourist rentals through Airbnb as a part time retirement project
Tesla Model 3 SR+, 2019
Previous EVs
Puey Bluey 2014 Miev
200,000 km , 124.000 miles.
Blackie - 2012 ES Miev 2 years - 67,000 km / (41,630 miles)
http://thecordstead.blogspot.ca/

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