How Well Do EVs Work in Extreme Cold or Heat?

Electric cars can handle harsh
weather conditions just like other cars

Electric vehicles can work in any
temperature, although they work best in a sort of Goldilocks temperature
range where the outside environment isn\’t too cold to harm
the battery capacity and isn\’t hot enough to require air conditioning. 

Electric vehicle range in extreme
cold and heat may not be as dire as you expect; for the record,
gas-powered vehicles aren\’t immune from temperature extremes either. Still,
it\’s essential to understand how heat and cold impact EVs.

Overall, EVs can and do perform
well in all types of weather. Some weather conditions, just like gasoline-powered vehicles, do mean that EV owners need to pay closer
attention to how they drive and conserve battery energy.

For example, EVs work better in
extreme heat than cold because cold enough weather will temporarily reduce the
capacity of EV batteries. However, turning the air conditioning on in hot weather can also reduce the overall range.

This is because electric
car batteries are significantly more advanced than most of the storms we run
into in our daily lives, but they are still bound by the same fundamental laws of
physics. That means EV batteries work in slightly mysterious ways to most of
us. 

The key to understanding the temperature
impact on EV batteries lies in remembering that, first and foremost, the
battery must be able to effectively hold and discharge energy. That means a
battery must not only be able to powerfully charge the car but also have enough charges to use when needed in different driving situations. 

The ability to hold those charges
is called \’capacity\’ or \’storage capacity.\’ When the car uses those charges, they are \’discharged\’ by feeding power to the EV\’s motor.

When a battery is exposed to
freezing temperatures, its capacity to store a charge can be diminished.
According to one study, lithium-ion battery charge capacity drops to about 77 percent at a testing temperature of 5 degrees
Fahrenheit, and measured discharge capacity drops to 82 percent at the same
testing temperature. 

EVs use lithium-ion (Li-ion)
batteries. These are rechargeable, lightweight, and have a higher energy
density than other types of rechargeable batteries. As a result, these
batteries are smaller than those in gasoline-powered vehicles.

Although battery capacity
typically increases as the temperature increases, highly high
external temperatures can cause deterioration and even lower the
operational life of a battery. That degradation can cause an EV battery to
perform less effectively. 

How Long to Expect Your EV Battery to Last 

How Temperature Specifically
Affects EV Range

Temperature issues don\’t just
affect the battery itself. It can also impact an EV\’s overall range. 

Temperature affects EV range from
both a capacity and use perspective:

1.      Low
external temperatures can reduce the storage capacity of EV batteries, which
means the EV can\’t store enough battery charges to go as far as it usually
would. 

2.     The
drain from heating or cooling the interior cabin of an EV can reduce the
available amount of stored energy needed to actually move a vehicle from point
A to point B.

The effect of low or high
external temperatures on battery storage capacity is an essential factor. Still, it doesn\’t fully account for the reduction in EV range in both low and
high temperatures.

It turns out that driver and
passenger comfort actually has a more significant effect on EV range because it takes a
lot of power to heat or cool the cabin of an EV in extreme weather conditions.
In fact, real-world testing has shown that the EV range drops to about 54 percent
when the ambient temperature dips to 5 degrees Fahrenheit. That reduction is
usually due to the power requirements of running an electric heater in
icy conditions.

This is one area where
gasoline-powered vehicles have an advantage because internal combustion
engines generate waste heat as a natural byproduct. That
makes it essentially free to heat a gas-powered car, while an EV instead needs
to send energy that could have otherwise gone to increasing its range into
running a heat pump or resistive heater.

However, gasoline-powered
vehicles experience troubles in extreme weather situations,
including reduced fuel economy in cold temperatures due to other factors.
According to the U.S. Department of Energy, gas-powered
vehicle fuel economy drops by about 15 percent when the temperature
dips to 20 degrees Fahrenheit compared to fuel economy in balmier conditions.

Image Credit Lifewire

When extreme temperatures swing
in the other direction, EV range reduction is entirely due to the energy costs
of cooling the cabin. This is where gas-powered vehicles don\’t have an
advantage because running the A/C in a gas-powered car takes gas that
could have otherwise been used to move the vehicle. 

According to the U.S. Department
of Energy, a gas-powered car can decrease its range by over 25
percent when running the A/C in scorching weather. In comparison,
the average EV can be expected to reach about 80 percent of its rated range in
conditions where the ambient temperature is 104 degrees. In that particular
situation, an EV will likely beat a gas-powered vehicle in terms of retaining
more of its range.

Heat Pumps vs. Resistive Heaters
in EVs

Both resistive heaters and heat
pumps can be used in EVs. The benefit of using a heat pump in an EV instead of
a resistive heater is that heat pumps are more energy-efficient. 

Resistive heaters convert
electrical energy into heat because they get hot when electricity flows through
them. Heat pumps, on the other hand, essentially just move thermal energy from
one place to another. 

An air conditioner is a kind of
like a one-way heat pump that moves heat from the interior of a vehicle to the
exterior, effectively cooling the interior in the process. Heat pumps are also reversible, which means one can be used to raise or lower the
temperature in an enclosed space.

In fact, according to one study from the NHTSA, the range of an EV with a heat pump is about 30 percent greater than
that of an EV equipped only with a resistive heater when operated in
freezing temperatures.

Heat pumps are typically capable
of operating in EVs in temperatures down to about 25 to 30 degrees Fahrenheit,
although efficiency does drop off the colder it gets. In even colder
temperatures, switching over to a resistive heater becomes more efficient.

9 Ways to Manage Range in Extreme
Weather Conditions

While it\’s true that EV range can
be reduced by both sweltering and cold weather, there are some things
you can do to improve the range of an EV in extreme weather conditions: 

1.      Reduce the use of air conditioning in hot weather. Set
the A/C at the highest temperature you\’re comfortable with, and consider
cooling off with other methods like a portable battery-powered fan and an ice
chest full of cool drinks when going on long road trips. 

2. use accessory systems unless you need them. All
the systems in your EV draw power from the same batteries, so everything from
using the entertainment system to turning on the headlights instead of just the
running lights during the day can cut into your EV\’s range. Keep nonessential
use to a minimum to improve your range when you need to draw
extra power to heat or cool the cabin.

3.     Heat or cool your EV\’s passenger compartment while it\’s still
plugged in. If you think ahead and get the cabin to a comfortable
temperature ahead of time, you won\’t need to burn through battery power once
you\’re on the road. If you can keep your EV in a garage, especially a
climate-controlled garage, all the better.

4.    Park in the shade when it\’s hot out. You\’ll
still need to run the A/C during sweltering conditions, but parking in the
shade will keep the passenger compartment cooler, and you won\’t need to use as
much energy to get comfortable.

5.     Try to stick to economy mode if your vehicle has it. Most
EVs have a model that provides better battery life and range at a performance cost. 

6.    Take it easy when starting and stopping. Sudden,
hard acceleration takes a lot more power than accelerating slowly. On the flip
side, your EV\’s regenerative braking system captures much more energy when you
brake slowly, anticipating a stop early, than when you slam on the
brakes at the last moment. Remember that driving in extreme
conditions, like ice or not, will also affect how long it takes you to
stop.

7.     Keep your cruising speed under control. Most
EVs provide the best battery life and extended range when you keep your speed
below 50 MPH. Efficiency, and spine, drop off sharply after that.

8.    Avoid charging your battery outside when the ambient
temperature is frigid. Battery charging capacity
drops off the colder it gets, so you start from a better place if your battery
isn\’t extremely cold during the charging process.

9.    Keep your load light. Did you load up for a
skiing trip or a day at the beach on the weekend? Driving around with all that extra
weight all week will reduce your range. If you have a rooftop cargo carrier,
consider removing it when it isn\’t in use, as the extra drag will also
reduce your coverage.

How Much Range You Need in Your EV