The arrival of winter for electric car owners opens up the same debate every year, that of reduced range and the challenges of driving in cold temperatures. Stories about drastic declines in autonomy and long waits at charging stations often create the perception that electric vehicles are unreliable in winter conditions.
Although there is some truth in these stories, it is important to emphasize that all cars, regardless of the drive, are less efficient in the cold. Vehicles with internal combustion engines also use more fuel. However, the specifics of electric vehicle technology require a certain adaptation and understanding of the processes that take place under the sheet metal from the driver. Fortunately, the loss of range is not permanent or harmful to the vehicle, and with proper planning and the application of a few key tips, winter electric driving can be just as enjoyable and reliable as summer driving.
Why do batteries not like the cold?
There are two main reasons why electric cars lose some of their range in winter – battery chemistry and the need for heating. The fundamental problem lies in the lithium-ion batteries that power most of today’s electric vehicles. Chemical and physical processes inside the battery slow down significantly at low temperatures. Cold acts as a resistance, slowing the movement of lithium ions through the liquid electrolyte, resulting in reduced available capacity and power. The ideal operating temperature for a battery is between 20 and 40°C, and anything below that affects its efficiency.
The second, and often bigger, “stealer” of energy is cabin heating. Unlike cars with classic engines that use waste heat generated by burning fuel for heating, electric cars must actively produce heat. Since their electric motors are extremely efficient and generate very little waste heat, the energy for heating the passengers and defrosting the windows must come directly from the high-voltage battery, the same one used for propulsion. This creates a double hit at range. The battery is less efficient at the start due to the cold, and at the same time it is additionally spent on heating. Newer vehicles equipped with a heat pump have an advantage because they can produce three to four units of heat for every unit of electricity used, which makes them significantly more efficient than older systems with resistance heaters.
How much range is lost on the downside?
Data collected in real driving conditions show that drivers can expect a range reduction of 20 to 40 percent. American research by the AAA association showed that at an outside temperature of -7°C, with the use of cabin heating, the average range of an electric vehicle drops by as much as 41 percent. This means that a car with a declared range of 400 kilometers in ideal conditions will, in practice, travel about 236 kilometers. It is important to emphasize that this loss is temporary and the range returns to normal as soon as the temperatures rise.
However, not all cars are equally affected. Recurrent’s extensive analysis of more than 30,000 vehicles in the US shows clear differences between manufacturers. Tesla, for example, demonstrates exceptional efficiency thanks to an advanced thermal management system known as Octovalve, which cleverly redirects and recycles waste heat from the powertrain and batteries to heat the cabin. On the other hand, some models, such as certain General Motors vehicles, show a greater drop in range because they appear to be optimized for maximum passenger comfort, using more energy-intensive resistive heaters that fire earlier to ensure faster cabin warming, but at the cost of a shorter range.
Tips for maximum range and carefree driving
The key to successfully using an electric car in winter lies in planning and changing habits. The most important tool in combating range loss is preconditioning. Almost all modern electric vehicles enable the heating of the cabin and the battery via a mobile application or by programming the departure time while the vehicle is still connected to the charger. In this way, the energy to achieve the optimal operating temperature is drawn from the electrical network, and not from the battery, thus saving precious kilowatts for the drive itself.
Once you get going, use heating systems wisely. Heated seats and steering wheel consume significantly less energy than blowing hot air through the entire cabin, and provide a direct and pleasant feeling of warmth. Adjust your driving style, use the Eco mode that limits power and optimizes consumption. Also, be aware that regenerative braking may be reduced or temporarily disabled until the battery warms up, as a cold battery cannot receive a large amount of energy at once.
Charging also requires adjustment. A cold battery charges more slowly, especially on fast DC chargers. To protect the battery, the management system limits the charging power until it warms up. For this reason, it is best to charge the vehicle immediately after driving, while the battery is still warm. If you use your in-vehicle navigation to drive to a charging station, many cars will automatically start preparing the battery for charging, which can significantly reduce the time spent at the charger. Whenever possible, park in a garage and keep the vehicle plugged into a charger. In this way, the system can use electricity from the mains to maintain the temperature of the battery, instead of consuming its own energy.