Do EVs lose range in winters? Yes, know why
What's the story
We all know the performance of electric vehicles (EVs) is affected by weather, especially when it comes to colder temperatures.
Despite improved battery technology and higher capacity, EV range anxiety continues to haunt potential buyers.
This is mainly because of the effect of cold weather on car batteries - something that is pretty common during the winter season.
Battery chemistry
The science behind EV battery performance
The performance of car batteries in EVs isn't much different from other batteries. However, their role in mobility poses unique challenges that aren't seen with other battery-operated devices.
Just like regular 12V car batteries used to power internal combustion engines (ICE), EV batteries are also sensitive to colder temperatures.
This sensitivity is due to the way electrons behave inside these power sources.
Temperature impact
Cold weather slows down reactions
At a molecular level, elements inside the battery react with each other, converting chemical energy into kinetic energy and stimulating electron movement.
In colder temperatures, these reactions slow down just like we do on a chilly morning.
This slowdown happens because of less effective reactions in the cold air and longer warm-up times for the electrons, which then generate less power.
Range reduction
Cold weather can reduce EV range by up to 20%
The use of heaters in the cold also sucks up the battery's energy, cutting an EV's range by as much as 20%.
However, some manufacturers have been able to keep this reduction to about 10%.
For example, if a vehicle's claimed range is 483km, it would actually be 443km in real-world conditions, irrespective of temperature.
In the cold, it could drop by another 45-90km.
Challenges
Charging is slower in winters
The same factors also slow down the charging process for electric vehicles in colder temperatures.
A key element of EV technology is thermal management, which is all about finding and maintaining an optimal temperature for efficient chemical reactions within the battery.
To tackle this, manufacturers are developing ways to cool batteries while keeping them warm enough for operation. This has resulted in 'pre-conditioning' features in many modern EVs.
Pre-conditioning
Pre-conditioning features in EVs
Pre-conditioning in EVs serves two purposes. One is to warm up the cabin with mains power (not battery) before starting a journey.
The second type of pre-conditioning protects the battery from degradation and offsets certain losses when charging in cold weather. It basically prepares the battery state for a safe, effective charge.
Manufacturers recommend pre-conditioning on mains power to avoid further range reduction due to self-preconditioning by the car with its own battery energy.