Electric cars in cold weather

By the end of this topic you can

• You can explain why an EV's range drops in cold weather.
• You can precondition the battery and cabin while the car is plugged in.
• You can plan winter trips with a larger range buffer.
• You can heat yourself efficiently and keep the windows clear.
• You can adjust your driving for snow and ice in a heavy, powerful car.

What you need to know and understand

• Cold temperatures reduce both battery performance and range; the size of the drop varies by model and conditions.
• Cabin heating uses battery energy; heated seats and a heated steering wheel use less than heating the whole cabin.
• Preconditioning warms the battery and cabin before you leave, using power from the charger if you are plugged in.
• A cold battery charges more slowly, especially at DC fast chargers, unless it is warmed first.
• Regenerative braking may be limited until the battery warms up.
• Winter tire rules vary: Quebec requires winter tires on passenger vehicles from December 1 to March 15, and BC requires them on many highways in the colder months.

Why the numbers shrink

A battery works through chemical reactions that slow down in the cold, so less energy is available and the car may also spend energy keeping the battery warm. On top of that, the heater, defroster and lights run more in winter. Short trips are hit hardest because the car keeps warming up from cold.

Warm up the smart way

Never block the front of the car or charging port with a snowbank, and park in a garage if you can, since a warmer battery starts with more usable range.

1. Set a departure time in the car or app so it preconditions while plugged in.
2. Clear all snow and ice from the windows, lights, roof and sensors before driving.
3. Use heated seats and the heated wheel, and set the cabin temperature a little lower.
4. Keep the windshield clear; use the defrost setting whenever it starts to fog, even if it costs some range.

Charging when it is freezing

Plug in at home whenever you can in winter so the car can keep the battery warm and precondition without using range. If you plan to use a DC fast charger, many EVs can warm the battery on the way when you set the charger as a destination in the car's navigation. Expect fast charging to take longer when the battery is cold.

Keep a bigger buffer in winter and do not plan to arrive with almost no charge. Chargers can be blocked by snow or out of service, so have a backup option.

Grip and control on snow

EVs are heavy and deliver power instantly, which can spin wheels on ice. Squeeze the accelerator gently, consider a lower regeneration setting on slippery roads if your car allows it, and leave much bigger gaps. Good winter tires make the biggest difference to grip, whatever drives the wheels.

Common mistakes

• Expecting summer range in January. Plan for less and keep a buffer.
• Heating the whole cabin to a high temperature. Use seat and wheel heaters first.
• Unplugging and driving off with a cold-soaked battery. Precondition while plugged in.
• Strong regeneration on icy roads, which can unsettle the car. Lift off gently or reduce regeneration.
• Leaving snow on the roof and sensors. Clear the whole car.

Test yourself: Electric cars in cold weather

Answer each question, then read the explanation. Questions come in a random order each time.