Battery Temps

i'm suggesting that it's the cold ambient temperature controlling actual ev distance and thus ev range estimate. edit: i haven't tried this, my garage is unheated and typically 45-55 degrees in winter. and i'm talking no cabin heat to keep battery warm, pure ev.

 

My winter temperatures are pretty mild by U.S. standards, and my car is always garaged when at home. It's never close to freezing in the garage. But I find the EV range estimate (usually around 13 miles peak in summer and 10.5-11 miles trough in winter) to be pretty accurate in practice. Lots of hills around here and traffic that won't allow one to drive very efficiently.

From my experience and what others have posted, I still suspect battery temp is very important. Perhaps an average battery temperature in the 40-50s in the winter and 70-80s in the summer can explain my EV range changes. Was hoping someone has or could pull some data on this.

 

Daytime highs under 0°F here. I fired up the engine upon reaching a hill, having already driven several blocks from my insulated but unheated garage.

The following hour of running from store to store was with nothing but EV, even though the engine had almost cooled down entirely.

There must be some degree of battery warmth allowing that... pun intended.

 

I don't have much use for a hair drier, because I bald.

 

Well....I didn't make a mistake in my profile.

 

also, it takes more energy to move the car in cold weather.

 

You suspect increased air density in cold weather and increased rolling resistence are the major factors? I don't know about the rolling resistence idea, but there may be something to increased air density. I'm still in the camp that thinks this is more cold battery pack related stuff. Would be fun to be a Toyota engineer to test all these things and get paid to do it!

 

Electrical resistance within the battery itself comes into play too.

Cold increases it.

 

I agree with everybody. My car being in my garage drives to the Fitness place totally on EV irrelevant of temperature. 2 miles. But coming back, after sitting for 2 hours, I have to be very light footed or I am in HV. Especially the last three days with the cold snap. For CA that's anything less than 32F. No doubt worst stats are obtained in MA and MI and all those other northland areas. I can get 13.9 Summer and Winter after a reboot.As Kitty says, the longer it's out, the worse the results. note: I posted on EV mile tracker in reference to adding heat to HV Battery.

 

John has hit it on the head. Battery comfort is everything. Are you greeting your battery every morning?

 

. There are definitely multiple factors involved, some major, many minor but all additive. Even some we or the engineers have not considered. YES, That would be fun. And to get paid for it.

 

it's getting thru engineering school that's the problem for me.

 

Heated seat(s) draw significant amount of juice as well. The longer the drive, the more it will reduce EV range.

 

I think around halogen bulb consumption (55W) per seat.

That brings up another point. Winter has less day light so the headlights will run longer, in combination with heated seats and slower driving speed -- can create a perfect storm for some.

 

better check the battery temp on this one:

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