In the electric vehicle world, preconditioning is the act of heating or cooling part of your vehicle before driving or charging the car. Preconditioning is a great tool, largely unique to EV ownership. It can save both electricity and time – and is something you’ll want to become familiar with as an EV owner.
Let’s start with the basics. Preconditioning can be done for both an EV’s cabin and its battery, and each has its own uses – and advantages.
As an example, you park your car outside – and it’s freezing. Brrrr. Instead of starting your car and waiting 15 minutes for your car to defrost, you set your car to heat the cabin and run the defrosters. By the time you get in your car to leave, the windows are clear of ice and the cabin is nice and warm. This can be done on a schedule, via the car’s smartphone app, or manually (like a gas car!). What a time saver! For added benefit, you can keep your car from draining its battery by preconditioning the cabin while the car is still plugged in.
Say you live anywhere the sun shines. On a sunny, 70 degree (F) day, a car cabin can reach over 100 degrees in less than half an hour, and nearly 115 degrees in just an hour. If you park to go shopping, you can set your car to maintain cabin temperature so it is nice and cool by the time you come back. One nifty thing about EV air conditioning systems is the fact they’re incredibly efficient. In most EVs, running the AC will cost you less than 1 percent per hour of battery life. Cooling is also schedulable on many EVs. Like with heating, cooling can also be done with the car plugged in so you don’t drain your battery while keeping the temperature.
With few exceptions, modern EVs have a system that regulates the temperature of the EV battery to maximize both its range and longevity. However, there are some situations where your battery needs to be deliberately preconditioned in order to maximize charge rates.
On some EVs, when you navigate to a DC Fast Charger (or Tesla Supercharger), the battery will begin to heat (or even cool) itself automatically before reaching the charger. While this is taking place, there is sometimes an audible hum that comes from the front or underside of the car, indicating that pumps are moving heat away from – or toward – the thermal “loops” in the battery packs.
The only time you would not want to use preconditioning is when your battery is too low to make it to the next charging station.
By popular brand
BMW: On the i3, drivers can set a departure time using the infotainment system; the car can be programmed to both heat the cabin and battery prior to departure.
Chevrolet: On the Bolt EV, climate is schedulable but drivers have no control over battery preconditioning. It is not recommended to fast charge a Bolt if the battery is cold; driving for a bit will warm it up.
Hyundai: The Kona EV has programmable climate preconditioning; the US Kona EV does not have active thermal management for its battery. The Ioniq 5 features the Electric Global Modular Platform, which includes thermal management for its battery.
Nissan: The LEAF’s climate conditioning is schedulable; its battery does not have an active thermal management system. The new Nissan Ariya (available beginning Fall 2022) will have active thermal management for its battery.
Tesla: Both climate and battery preconditioning are schedulable; battery preconditioning is also enabled within a certain distance from a Tesla Supercharger when set as a navigation destination.
In short, preconditioning has multiple uses – it can be beneficial for both passenger comfort and charging efficiency. Preconditioning your cabin and using seat or steering wheel heaters is almost always a good idea in the winter to save range. Consult your manufacturer’s user manual for more specific information on preconditioning features and how to use them.