Cold weather behaviour and observations

[insightman]

I was taken aback when I read that in the manual. They sure don't advertise it. What happens to us here in Vermont where -22F is not unusual and we have the US model with no battery heater? Glad I am retired. It's been many decades since I had to call in because the car wouldn't start in the cold. I guess it's back to the 20th century future.

The Canadian Clarity's battery warmer (which works only when the car is plugged in) doesn't kick in until the battery is fully charged. If you set the built-in charge timer in your U.S. Clarity so that charging completes just before you plan to start your drive, the battery will be just as warm as a Canadian battery before the battery warmer comes on to maintain the temperature achieved through charging. I'll admit I'm guessing that the battery warmer only maintains the charging temperature, but because the battery warmer doesn't kick in until after charging, I'm assuming the warmth generated through charging is sufficient to cope with -22F. At -23F, I'm not so confident.

 

[Klong]

I did a quick experiment to see how much range is lost due to using the cabin heater.
Temperature for both days was averaging -4C or 26F.
With heat - mileage driven plus small remaining range - 52km or 32miles
Without heat - 85km or 53miles
Average speed was 60kph or 37mph
Almost 40% loss in range that should become higher when temperatures drop even lower. Although below -12C or 10F I had my ICE turn on when I start the car (not plugged in - so no battery warmer) and run for 5 minutes.

 

[Jarome]

At about 50F, my battery range dropped to about 35 miles. Is this normal? I also worry about doing small charges after driving around town (10 miles). Does this hurt the battery?

 

[Richard_arch74]

At about 50F, my battery range dropped to about 35 miles. Is this normal? I also worry about doing small charges after driving around town (10 miles). Does this hurt the battery?

@Jarome, that's normal assuming that you are heating your cabin and or seat heaters. Cold temps + cabin heatin + seat heaters ~40% less range. I haven't seen any evidence that topping off your SOS to 99/100% hurts the battery but somebody with more experience with number of life charging cycles with this battery will have to answer your last question.

Sent from my SM-G955U using Inside EVs mobile app

 

[David Towle]

I did a quick experiment to see how much range is lost due to using the cabin heater.
Temperature for both days was averaging -4C or 26F.
With heat - mileage driven plus small remaining range - 52km or 32miles
Without heat - 85km or 53miles
Average speed was 60kph or 37mph
Almost 40% loss in range that should become higher when temperatures drop even lower. Although below -12C or 10F I had my ICE turn on when I start the car (not plugged in - so no battery warmer) and run for 5 minutes.

View attachment 3068

What I've seen so far is in agreement with your findings. Of course range will be even lower on the highway at normal low 70s speeds.

What you can do to minimize the power usage by heat:
1. Turn down the temp to Low or the lowest you can tolerate.
2. Use seat heaters
3. Don't use auto on the climate control and turn the fan speed to the lowest
4. Use the foot/defrost climate setting (further restricts airflow and puts some warm air on the windshield where needed)
5. Instead of above use the defrost button and then turn the fan back down to low, although I'm afraid in some conditions this may invoke the AC which also uses power.
6. Push the recirc button. I find after 5-10 minutes I have to cycle back to fresh air for a minute as fog starts forming.

Or you can just use HV mode and stay toasty warm with the free engine heat!

 

[DucRider]

Remember that even if the ambient air is -30C, it will take some time for the pack to reach that temp. At -30C air temp, it would take a loooong time to cool the battery to that level. Lower temps with a greater differential or windy conditions will speed the process. There is a fair amount of thermal mass in a battery (the Clarity battery is large compared to other PHEV's) and air is a fairly poor heat conductor (which is why liquid battery cooling is much more effective).

 

[MNSteve]

Remember that even if the ambient air is -30C, it will take some time for the pack to reach that temp. At -30C air temp, it would take a loooong time to cool the battery to that level. Lower temps with a greater differential or windy conditions will speed the process. There is a fair amount of thermal mass in a battery (the Clarity battery is large compared to other PHEV's) and air is a fairly poor heat conductor (which is why liquid battery cooling is much more effective).

Unfortunately, I think "overnight" qualifies for "some time". Especially if the car is parked outside and there's wind.

My EV range has now dropped below 30 with temps in the garage in the 20°F range. Preconditioning with a level-1 charger is pretty ineffective; after 20 minutes the temp had reached a whopping 32°F. I am considering a level-2 charger but the expenditure just so that I can leave in a warm car seems unjustified. My driving habits support an overnight charge so I probably won't spring for the L2 charger.

And the other thing I won't do is skimp on the heat to extend the EV range. I did not buy this car so I could be uncomfortable driving it. I love the idea of using renewable energy to propel myself down the road but I do not enjoy doing it while my teeth are chattering.

 

[RichL]

At about 50F, my battery range dropped to about 35 miles. Is this normal? I also worry about doing small charges after driving around town (10 miles). Does this hurt the battery?

Jarome,

It appear to have less affect on battery life than a full cycle charge/discharge.
This article on EV batteries is an interesting read:
https://cleantechnica.com/2018/08/26/the-secret-life-of-an-ev-battery/

Based on what I've seen in the Clarity vs. say a Leaf, Honda appear to have been very conscious of preserving battery life and conservative in designing the "virtual battery" and the systems that affect the life of the battery such as regen, battery warmers, battery cooling etc...

 

[su_A_ve]

As soon as temps dropped and started to use the heater, range went down to the mid 30s from a summer in the high 40s. A full charge would give me a round trip from home/work and then some miles extra for errands, but now in the winter, it's much tighter. Also, with the L1 charger (which I mostly use on the weekends) I noticed I would get approx 4 miles per hour of charge in the summer, and this is now down to 3 miles per hour of charge. So on a few long weekends I've started to use HV mode, since gas prices dropped as well, enough to be on par with electricity rates.

But, I noticed total HV range is way off. Today I drove 13 miles and used 25 HV miles (EV stayed the same) starting with a full tank of gas and an HV range of 351. Almost double... I do have the HV range fix applied.

 

[Robert_Alabama]

If starting HV range was 351 miles and tank holds about 7.2 gal, then the car expected you to get 48.75 mpg based on your recent HV driving performance. Apparently, you drove 13 miles and burned about a half gallon of gas (dropping the HV by 25 miles at 48.75 mpg estimate). That means you apparently averaged about 25 mpg on your 13 mile trip today. Start of trips can be less efficient (cold engine). Did you idle at any lights/stop and go/accelerate harder than usual? I wouldn't worry much about a 13 mile trip as it really is too small a sample to tell much.

 

[E10]

Unfortunately, I think "overnight" qualifies for "some time". Especially if the car is parked outside and there's wind.

My EV range has now dropped below 30 with temps in the garage in the 20°F range. Preconditioning with a level-1 charger is pretty ineffective; after 20 minutes the temp had reached a whopping 32°F. I am considering a level-2 charger but the expenditure just so that I can leave in a warm car seems unjustified. My driving habits support an overnight charge so I probably won't spring for the L2 charger.

And the other thing I won't do is skimp on the heat to extend the EV range. I did not buy this car so I could be uncomfortable driving it. I love the idea of using renewable energy to propel myself down the road but I do not enjoy doing it while my teeth are chattering.

I also use a level 1 EVSE and if it is really cold and I want to actually get a warm car by pre-conditioning, I will go outside and unplug the charging cable while walking the dog in the morning.

 

[Chooch]

Anyone notice more engine noise in cold weather?
Temps have been around 20 degrees F this week and I can really hear the engine.
Not sure if it's just me or my hearing is improving or I'm listening more closely.
Yesterday on the highway was the first time I noticed regen chevrons flashing and also lockup clutch did not engage.
Both returned to normal within the first 50 miles.
I don't usually use the ACC and it was kind or erratic on the gas and brakes, so maybe the heavier demand on power combined with cold had an effect.
I typically drive like an old guy from Florida, the only thing I'm missing is the hat with a feather in the band.

Well, I have noticed that when I turn the heater on the engine gets louder. It quiets down when heater is turned off.

 

[Art]

I think it is important to differentiate US and Canadian models of the Clarity as the Canadian model comes with a built in battery warmer - the US model has power seats

I test drove and inspected the Clarity in the US on vacation and ordered one from home in Canada last March. The vehicle in the US had power seats but the car delivered to me had manual seats. I was told this is all that is available in Canada. However I note that in BC and Quebec you can get a Clarity Touring with power seats - interesting as I am in Ontario. I am not even certain there is a battery warmer on the car.

 

[Atkinson]

Well, I have noticed that when I turn the heater on the engine gets louder. It quiets down when heater is turned off.

How did you test?
On the road? what speed?
Idling? inside or outside of car?
Did it seem like exhaust noise or engine harmonics?
I don't want to poison your findings, but I have read that there are issues with the Accord Hybrid noise canceling system failing and causing the cabin to resonate with engine noise.
The engine noise I get doesn't bother me, but it's so different than what I remember from summer.
Wondering if there is an exhaust changeover in winter to get more heat.
As far as I see, there is no exhaust heat recovery device on the Clarity as is on the Accord Hybrid - so the exhaust noise should not change either way.

 

[insightman]

However I note that in BC and Quebec you can get a Clarity Touring with power seats - interesting as I am in Ontario. I am not even certain there is a battery warmer on the car.

It would be interesting to discover if those Claritys had Canadian or US serial numbers.

 

[Klong]

I test drove and inspected the Clarity in the US on vacation and ordered one from home in Canada last March. The vehicle in the US had power seats but the car delivered to me had manual seats. I was told this is all that is available in Canada. However I note that in BC and Quebec you can get a Clarity Touring with power seats - interesting as I am in Ontario. I am not even certain there is a battery warmer on the car.

I purchased my Clarity in Quebec and I could not get power seats. I was told that in Canada, power seats were removed and a battery warmer was installed instead. When I look at my electrical charge (Chargepoint) graph from overnight charging on very cold nights I can see a low power draw during the night - the battery warmer drawing power.

 

[JJim]

However I note that in BC and Quebec you can get a Clarity Touring with power seats - interesting as I am in Ontario. I am not even certain there is a battery warmer on the car.

I purchased my Clarity in Quebec and I could not get power seats. I was told that in Canada, power seats were removed and a battery warmer was installed instead.

Same here in BC, no power/memory seats for Touring, that's why I got Base

 

[David Towle]

Power seats are just annoying anyway.

 

[Klong]

Interesting behaviour in very cold weather (below -15C or 5F) - if I precondition (level 2 charger) my car for 20 minutes or more it appears to warm the battery up even more than just the battery warmer does. Case in point, my preconditioning failed to warm my car the other morning when it was very cold out, so I manually started the cycle - however it only ran for 10 minutes before I left for work. When I turned my climate control on after 3-4 minutes of driving (it was starting to get cold in the car) the ICE kicked in immediately. The ICE cycled on and off after the initial longer startup run for most of my trip to work (40k - 26miles). When I get 20 minutes plus of preconditioning, the ICE doesn't turn on at all. I am attaching a graph from my Chargepoint to show the cycling of the battery warmer and the preconditioning draw on a normal (very cold) morning. Wednesday the overnight low is supposed to be -26C or -15F. It will be interesting to see if the preconditioning will be enough to keep the ICE from coming on. I detest using gas on my daily commute.

 

[Kranberry]

For my experience. It was around the same temps -15C/5F when I went to start my car. I was probably around 60% battery, and I wasn't plugged into any charger. Overnights with wind chill probably dipped down to -20C or lower, but only -15C when I started my car. Upon start up (no problems starting), the ICE immediately turned on and stayed on for around 8-10 minutes. After that I was in EV mode no issues.

I have found with temps dipping into -15C and the stop and go traffic during rush hour, killing my range. In the summer I could get over 80km/50miles on a single charge. Now with really low temps I'm getting almost half that.