How to take care of your electric vehicle in freezing conditions: 10 tips

Winter is approaching and if you own an electric vehicle, you need to start equipping yourself, but why?

Well, because your electric vehicle’s performance deteriorates when the temperature starts to drop, and there are some important things to know about using and maintaining your electric vehicle in the winter.

How much range does your electric vehicle lose due to cold weather?

If you’ve used a smartphone in freezing conditions, you know that battery performance suffers when the temperature drops below freezing.

As electric vehicles use similar battery chemistries, their performance also decreases as the temperature drops. Not only that, according to tests conducted by the American Automobile Association (AAA) in 2019 [PDF], battery life decreased by 12% at 20 degrees Fahrenheit compared to 75 degrees Fahrenheit. This decrease in range increased to 41% when the cabin heater was used.

Therefore, it is safe to say that the range of your electric vehicle decreases when it is cold outside, but why is this happening?

Well, there are two main factors, but before we get to the nitty-gritty, let’s understand lithium-ion batteries.

How do lithium-ion batteries work?

Simply put, your vehicle’s battery converts chemical energy into electrical energy. To do this it uses three things a cathode, an anode and an electrolyte.

The anode forms the negative terminal of the battery and has a high density of electron-rich lithium atoms. These atoms are trapped in a layer of graphite and want to get rid of their only valence electron to become stable. This tendency of atoms to lose electrons is known as electropositivity, and lithium being a metal, is very electropositive.

On the cathode we have cobalt oxide which forms the positive terminal. This terminal is positively charged because the cobalt atoms have lost electrons to oxygen and have a strong tendency to gain electrons. This tendency of an atom to gain electrons is known as electronegativity.

To summarize, the lithium atoms at the anode want to lose electrons, while the cobalt at the cathode wants to gain electrons. Because of this, electrons move from the negative terminal to the positive terminal, and it is this movement of electrons that generates electricity.

In addition, an electrolyte is placed between the anode and the cathode, which allows lithium ions to pass from the anode to the cathode.

The aforementioned process occurs when discharging, and the exact opposite occurs when charging the battery.

Why does the range of your electric vehicle decrease in winter?

Now, in a hypothetical environment, the above reaction should continue indefinitely, but as we all know, batteries don’t last forever. This is due to other reactions that consume the electron-rich lithium atoms, degrading battery performance. These reactions occur at different rates at different temperatures.

Therefore, cell manufacturers define a temperature range in which batteries can operate optimally. For lithium-ion batteries, the discharge temperature is between -4 and 140 degrees Fahrenheit, while the charging range is between 0 and 45 degrees Fahrenheit.

This clearly shows that lithium-ion batteries can discharge in sub-zero temperatures, but charging them at the same time is not advised. In addition, lithium-ion batteries offer the best discharge performance at room temperature, and in extreme situations their performance degrades.

The reason for this degradation is as follows.

When you charge your lithium-ion battery, the charger extracts lithium ions from the cathode, converts them into lithium atoms by adding an electron, and embeds them into the graphite of the cathode.

When the temperature decreases, the lithium atoms do not intercalate in the graphite; instead they cover the surface of the anode causing lithium plating. This lithium plating phenomenon converts the otherwise electropositive lithium atoms into an inert metal. As a result, the number of lithium atoms available to provide free electrons decreases, which decreases battery performance.

Lithium plating increases when high charging current is used.

On the other hand, when your battery discharges, the lithium ions must pass from the anode to the cathode. During this process, ions must move through the electrolyte, but as the temperature decreases, this process slows down as the resistance of the electrolyte increases. This increase in resistance reduces the range offered by your mobility device.

In addition to the factors listed above, the battery is responsible for keeping the cabin warm when the weather outside is cold. For this reason, the battery must operate both the vehicle and the heating system, further reducing range.

10 things you can do to improve your EV experience in winter

Now that we have a basic understanding of why your EV’s performance drops when the temperature drops below freezing, we can see how you can improve your EV experience in the winter.

1. Do not fast charge your electric vehicle in cold weather

As explained earlier, lithium plating is a battery’s biggest enemy in cold weather. Not only that, but the phenomenon increases when the charging current is high.

Therefore, it is not recommended to fast charge your electric vehicle when the ambient temperature is below zero.

2. Charge your electric vehicle slowly at night

If you plan to travel long distances with your EV, it is best to fully charge it at night using Level 1 charging. Not only will this give you a full charge in the morning, but it will also provide slow charging current which will not damage the battery.

Not only that, but if you don’t have a heated garage to charge your EV in, trickle charging will keep your battery warm, protecting it from cold weather conditions.

3. Be prepared for a longer charging time

Because your battery’s electrolyte slows in cold weather, charging takes longer. Therefore, you should be prepared for a longer charging time when charging in cold weather.

4. Don’t leave your battery dead in cold weather

If you will not be using your vehicle for a long time, it is advisable to charge it to 70% before storing it. This will reduce feedback that degrades your battery health.

In addition to this, you should not leave your vehicle with a low battery percentage overnight as it harms your battery health.

5. Park your vehicle in heated spaces

If you have a garage where you can keep your car overnight, it’s a good idea to keep the room temperature between 68 and 72 degrees Fahrenheit.

This will reduce the internal reactions that degrade your EV battery, providing better battery performance over an extended period.

6. Preheat your electric vehicle before going out

Before leaving for work, it’s best to warm up your car slowly while you go about your daily chores. Not only would it keep you warm when you go out, but since the car heats up slowly, the battery won’t be strained too much while driving.

Plus, you can also connect the charger to your car while you’re warming it up so power is drawn from the charger and not the batteries, giving you more range for the day.

7. Keep the heat low

If you’re planning on taking a winter road trip, your car’s heater is the battery’s biggest enemy. Although it keeps you warm, it degrades your battery life.

Therefore, rather than running the heater on full blast, it is better to use the heated seats and steering wheel to keep your hands and body warm. This could increase the range of your electric vehicle and you won’t have to charge your vehicle as often.

8. Use Lower Regeneration Break Levels

Most electric vehicles offer varying levels of regenerative braking. This allows the electric vehicle to charge when its brakes are applied. That said, if you are riding in cold weather, a higher regeneration level can cause your vehicle to skid on snowy surfaces.

Additionally, the high level of regenerative braking would deliver high currents to the battery, which could damage it due to colder temperatures.

9. Use eco mode

If you’re not planning on doing a drag race on your EV, it’s best to turn on ECO mode when it’s cold outside. This would provide better battery life and reduce the drain on your battery, thus providing better battery health.

10. Go through the Internal Combustion Engine (ICE) Checklist

While driving an EV is a different experience than an ICE, it still has external components like tires and windshield wipers, which don’t work well in cold weather. Therefore, it is advisable to get a new pair of windshield wipers and snow tires.

Is it safe to drive an electric vehicle in freezing conditions?

An electric vehicle offers users a different driving experience and comes with many bells and whistles. That said, the cold is the Achilles heel of an electric vehicle because it hampers the chemistry of the battery that powers it.

Electric vehicle owners can get the most out of their vehicles equipped with smart battery management systems and electric vehicle handling best practices.