There has long been a lot of discussion surrounding electric vehicles and the cold weather over the past several years.
Since EVs are no longer sitting on the fringes of the automotive marketplace, and are being thrust faster and faster into the central mainstream, it stands to reason that a growing number of people are wanting to know about the limitations and potential drawbacks of the technology. One such drawback long mentioned by EV critics is the vehicles’ performance in the cold, and that includes top-end cars like Tesla.
What is the main problem? Chiefly people are worried that extreme cold temperatures will have a marked effect on the driving range and battery performance. These criticisms are not entirely unfounded, since we do know that the range of a Tesla Model 3 will be less on a winter’s day than on a summer’s day. But can it be even worse? Can the battery actually freeze in an extreme cold snap? This is something we are endeavoring to find out in today’s blog.
Can a Tesla Battery Freeze?
While there don’t appear to be any notable cases of Tesla batteries freezing solid, that might just be a happy result of people’s habits rather than because it’s an impossibility. Tesla batteries do contain a liquid electrolyte, similar to many other lithium-ion battery designs. If this liquid is subject to sufficiently low temperatures for protracted periods of time, then in theory it could freeze, and in doing so could cause significant damage to battery cells.
The good news is that it would take quite the low-temperature battering to get such a result, but Tesla does include warnings about such outcomes in their own manuals (see below for more). Only temperatures in places like Siberia could likely pose such a threat to a Tesla battery, but that doesn’t mean the already pretty savage cold of places like Wisconsin and Maine, for instance, couldn’t do a real number on them.
Whether or not the battery freezes solid is not really the important point. What Tesla owners and other EV drivers and owners need to know is that their car battery does need care and attention when temperatures are falling.
Why and How Does Cold Affect EV Batteries?
As we mentioned above, lithium-ion battery packs like the one that powers a Tesla Model 3, Model X or other Tesla model rely on a liquid electrolyte, which becomes increasingly sluggish in performance the colder it gets. In principle, it’s not a dissimilar idea to old engine oil becoming more viscous when temperatures dropped, forcing you to warm up your car more before setting off on any journey. Cold makes the electrolyte work slower, which is the main reason the battery can’t perform as well as it should. That inevitably translates into a reduction in the total range the car can manage in a single charge.
How Else Does Cold Impact a Tesla’s Performance
Extremes of any temperature create a more taxing environment for your Tesla’s power systems to manage. High temperatures create a greater need for energy for cooling, and extremely low temperatures create a greater need for energy for heating. Let’s also not forget that Teslas — like all battery electric vehicles (BEVs) — does not have an internal combustion engine acting as a rapid source of easy heat under the hood. That means that all heating must come from the car’s own heating systems — heated seats, resistance heaters, etc.
More draws on your power source mean that the range is inevitably reduced. How much range one loses exactly depends on a number of factors, but reports from users in cold areas of North America and Europe seem to paint a picture of somewhere between 10 and 20 percent of battery power being lost on cold winter days.
One further result of cold weather on your Tesla battery is that your charging times will be extended. What some experts point out is that far from “hating the cold” lithium-ion batteries are actually fine in extremely low temperatures. What really can cause damage, however, is attempting to charge the battery while it’s stone cold. It’s for this reason that your Tesla has systems in place to preheat the battery before charging begins. The extra wait for the battery to warm up will add to your charging time, so you should factor that in if you’re plugging in after the car has been sitting in cold temperatures for several hours or more.
What Does Tesla Recommend to Its Customers?
Tesla does give considerable warning and advice to its customers on the subject of using one’s Tesla in cold temperatures, and winter driving in general. One thing they point out, for example, is not to plug the car into a Supercharger point until the battery has had sufficient time to warm up. This can be achieved by preconditioning the car and then driving it a short distance to the Supercharger.
In the “Climate” section of the Tesla smartphone app, there are two key functions that users should be aware of when preparing their battery for a winter’s day, namely:
Preconditioning is essentially another way of saying “warm up” like we used to when we started our car on the driveway and left it running for a few minutes before actually setting off. The difference, however, is that you can control it remotely with your smartphone, which is pretty nifty. Activating preconditioning will warm the battery and the passenger cabin, and because your car is plugged in — we assume — then it will do all of this without drawing any power from the battery pack, but rather from your charging supply. This is one of the key reasons that Tesla recommends that you keep your car plugged into your home charger when it’s parked up, since it allows you the option to activate these features with a single button.
Using “Defrost” will specifically warm up the battery, which is a useful step if you want to get the car ready for charging while you’re out on the road. These features can also be scheduled each day so you don’t have to actually worry about remembering to activate them at certain times. For example, if you normally set off for work at 8:00am, you can set these preconditioning and defrost functions to start automatically at 7:00am. These scheduling settings are also within the Tesla app.
The Snowflake Icon
One more key feature to look out for in your Tesla is the blue snowflake icon that may appear on your touchscreen. If you’ve seen this before and thought it was just a warning about the outside being cold, then you need to know more about this. When this icon appears, the system is telling you that your battery is too cold to get access to the entirety of its energy in storage. That being so, it will limit certain functions, including regenerative braking.
When your braking can be affected by the cold, it’s time to take notice and try to take steps to avoid that icon appearing, if possible. The appearance of the snowflake invariably means you haven’t properly warmed up your battery. When it is sufficiently warmed up, the snowflake icon should disappear.
What Steps Should Tesla Owners Take in Cold Weather?
There are a number of things that one can do to keep the Tesla running better in cold weather. Let’s take our above-mentioned battery warming as read, and focus on some additional things one can do. Warming the battery is critically important, of course, but there’s more one can do to optimize performance:
Don’t drive too fast or too aggressively
In truth, the biggest drain on your Tesla battery is never the cold weather, but rather one’s driving style, and in particular the way one uses the accelerator and brake. Those who drive harshly and aggressively tend to use up battery capacity faster, but also to wear out key components on their vehicle more quickly. This is something that EVs and regular gasoline cars actually have in common.
Going easier on the acceleration, braking more gently, and relying more on coasting and momentum are all ways to help improve battery and general performance in colder weather.
Use battery saving wherever possible
Tesla has a number of energy-saving settings one can use, and the winter time is a good time to put them into action. If you live in a place where consistently cold temperatures day-in, day-out through the winter are inevitable, these settings can help make a real difference.
Keep doors and windows closed
Another good way to ensure heat isn’t lost after being generated is keeping the doors and windows closed, and leaving doors open too long when getting in and out. If heat escapes, it has to be replaced with new heat, which takes more energy.
Keep the car plugged in when not using
Follow Tesla’s recommendations by keeping the car plugged in while you’re not using it, be it at home or at work (if possible). Keeping it connected to a power source will help to ensure the battery can easily be kept at the optimum temperature before setting off anywhere.
Use preconditioning to melt off excess snow
If your Tesla is covered in snow, use the preconditioning settings to warm it up and melt off the bulk of the snow. You can brush away any remaining snow before departure. Leaving snow on the roof or hood adds excess weight to the car, which in turn requires more energy from the battery to move the vehicle. An EV is heavy enough without throwing additional snow into the bargain.