New Study: Extreme Temperatures Affect Electric Vehicle Ranges

Electric vehicles (EVs) are energy efficient and environmentally friendly with the added benefit of reducing motorists’ fuel costs. But, just as motorists need to know how far the gas in their tank will take them, EV drivers need to be aware of how far their vehicle can travel on a single charge. According to new AAA research conducted with the Automobile Club of Southern California Automotive Research Center, electric vehicle range can be reduced by up to 57 percent based on outside temperature.


“Electric motors provide smooth operation, strong acceleration and require less maintenance than internal combustion engines,” said the Automotive Research Center (ARC) Manager and Chief Engineer Steve Mazor.  “So with more hybrid and plug-in vehicles in the market place motorists have more options to choose from. However, EV drivers need to carefully monitor range in hot and cold weather.”


To better understand climate impact on electric vehicle batteries, AAA conducted a simulation to measure the driving range of three fully-electric vehicles in cold, moderate and hot weather. Temperature made a big difference in driving range for all three EVs.


Tests were conducted on a 2013 Nissan Leaf with a factory heating unit dedicated to the battery pack; and a 2012 Mitsubishi iMieV and 2014 Ford Focus Electric with dedicated active thermal management (heat and A/C) for the battery pack.


Vehicles were tested for city driving to mimic stop-and-go traffic and to better compare with EPA ratings listed on the window sticker. The average EV battery range in AAA’s test was 105 miles at 75°F, but dropped 57 percent to 43 miles when the temperature was held steady at 20°F. Warm temperatures were less stressful on battery range, but still delivered a lower average of 69 miles per full charge at 95°F – 33 percent lower.


The ARC 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 exhausted.


AAA has launched mobile recharging trucks and EV charging stations to support members who drive electric vehicles. EVs provide owners with many benefits, but every motorist needs to be aware of conditions that can impact vehicle driving range, said Mazor. EV drivers need to plan carefully in hot and cold weather, he added. Mapping tools such as the AAA TripTik® Travel Planner pinpoint charging stations to keep motorists on the go.  

Additional information regarding AAA’s electric vehicle testing