AAA range test of Leaf and Miev in hot and cold weather

[klindholm]

Here is a link to an article on the effects of heat and cold on the Leaf and the iMiev:

http://www.usatoday.com/story/money/business/2014/03/20/cold-sharply-cuts-range-of-electric-vehicles/6622979/

Kevin

 

[dniemeyer99]

As a person that drives an Imiev, I can say the number of 57% is way to high. I question the value of the base number that was being used. The base number being the EPA value for a full charge. On the Imiev, that would be 62 miles ( approx. 100 km). But the car can go further 75-85 miles under the right conditions, stop and go, no heat or A/C.

I live in Canada and have regularly travel at -25 to -35 deg c with my daily commute. I have been getting 40 miles per charge with full heat on.

If the author of the report uses 85 miles rather than the 62 miles, you would get two very different conclusions.

For example : (85 miles - 40 miles) / 85 miles = 53 %

However is you use the EPA value you get :
(62 miles - 40 miles) / 62 miles = 35 %

I would say that the study was therefore bias to reflex the higher number when they should be using the EPA value as the real comparison.

Dave

 

[aarond12]

I want to know how they got an average of 105 miles at 75°F out of an i-MiEV, FFE, and a LEAF. Were they driving at 35 MPH on a test track? Doesn't seem like a realistic test to me.

i-MiEV EPA Rating: 62 miles
FFE EPA Rating: 76 miles
LEAF EPA Rating: 75 miles

 

[JoeS]

I went to the AAA news release and it was of no help.

Sure, 105 miles range on a dynamometer would be a piece of cake for an i-MiEV as it doesn't have to deal with wind resistance. I wouldn't be surprised if higher speed on the dyno would be even better as it would diminish the effect of fixed vehicle loads.

The problem I have with all of these "winter" range tests is that the uncontrolled variable is heater usage - that alone can swamp out any possible diminished battery capacity due to low temperature. Any range testing should NOT include any heater or aircon use.

 

[RobertC]

From AAA's website:
"AAA performed testing between December 2013 and January 2014. Each vehicle completed a driving cycle for moderate, hot and cold climates following standard EPA-DOE test procedures. The vehicles were fully charged and then “driven” on a dynamometer in a climate-controlled room until the battery was fully exhausted."
As a AAA member, I sent them an e-mail about how disappointed I was that AAA would publish a misleading article using an unrealistic test and misinform the public about electric vehicle range.

 

[Vike]

What got my attention was this:

Brannon said two of the vehicles, the Mitsubishi and the Ford, were equipped with dedicated management of the battery temperature.

Wow - once a wrong idea takes hold, it just doesn't let go. Mitsu's weasel wording confused many of us (myself included) back in 2012, leading us to believe that the i-MiEV provided a forced-air thermal management system, circulating cabin air through the battery compartment to cool or heat it. As our more intrepid contributors dug into the details, however, we learned that just ain't so. The only i-MiEVs that have any kind of thermal management are cars equipped with CHAdeMO or the cold weather package, and even in those cases, battery compartment heating or cooling is performed only during charging.

So even in March 2014, even professional testers remain confused about this. Certainly makes me feel less dumb about the whole thing.

 

[dniemeyer99]

Found this on the web. Interesting as it says that in cold weather the cost savings for EV's are greater.



http://news.fleetcarma.com/2014/01/16/cold-weather-fuel-efficiency/

Dave

 

[NeilBlanchard]

People sometimes forget that ICE cars get (much) lower range in cold weather, too. Especially on short trips - the engine never gets warmed up if you drive less than 6-8 miles or so. And all cars have more aero drag in cold air, that is definitely noticeable. Gears and bearings and tires, etc. are all higher friction in the cold.