Climate-proofing EVs
Strategies for weather resilience
Climate change is making worldwide temperatures more extreme. Even though electric vehicles (EVs) were designed to help prevent this by cutting emissions, they face their own set of challenges as a result.
In the UK, temperatures in the winter typically reach 0 degrees Celsius, 15 degrees colder than what a lithium-ion battery is designed to perform at. What does this mean for getting to work in the morning or making that long road trip to see family?
Understanding how weather impacts these vehicles and what can be done to stop it will make life as an EV owner easier and safer. It will also encourage others to take the plunge, knowing that no matter the weather, saving the world won’t be an inconvenience.
How cold weather affects EVs
Cold weather affects EVs in many ways, some of which will impact their charging times, range, and overall performance. Knowing about these effects is important as it prepares you as a driver of what to expect and how to avoid them.
Here are some of the most common effects of cold weather on EVs.
Longer charging times
Charging your EV already takes time, and it can become longer when temperatures drop. This is due to a chemical reaction inside the battery, which controls the energy released to power the car. This reaction normally flows without any issue, but in cold weather, it gets sluggish.
With things moving slowly inside the battery, accepting energy from the charger is less efficient. This leaves you waiting for up to two hours longer than usual.
Shorter driving range
EVs can’t travel as far in cold weather on a single charge, with many models losing anywhere between 10% to 36% of their range.
This reduced distance is a side effect of multiple things that happen to EVs in cold weather. A lot more energy is used to heat the rest of the car, to keep it comfortable for the driver and the inner workings.
This is already a blow to performance, but as mentioned before, EV batteries are slower in the cold. Because of this, sharing energy with different parts of the car takes longer and is less effective.
So, EVs need more energy in the cold to keep warm, meaning there is less leftover for powering the battery from A to B. In some cases, this wouldn’t be an issue with plenty of charging stations on the route, but it can delay long-distance trips.
Less battery capacity
As well as being unable to drive as far, the overall capacity of EV batteries can be lowered by 41%. This makes owning an EV less convenient during the winter as you will need to charge more, plan routes, and sacrifice some features to save energy.
This strain can damage the battery long-term and make it wear out earlier than planned. EV batteries have small parts that may need to be replaced more often because cold temperatures make them less efficient.
How hot weather affects EVs
High temperatures don’t mix well with delicate battery parts and cause poorer performance and safety concerns. This doesn’t bode well for EV owners, as the climate only gets hotter with temperatures rising faster than ever.
Here are some of the ways that hot weather affects EVs.
Damaged battery health
Hot weather weakens EV batteries. They lose capacity and wear out as chemical reactions within the battery speed up, building pressure and leading to cracks.
This is dangerous and causes chemicals to slow down and battery performance to drop. If nothing is done about this, your EV battery won’t last long and must be replaced.
Charging in hot weather also makes EV batteries heat up much faster than intended. To prevent batteries from overheating, electric cars have monitors that will stop charging if temperatures are too high. This can inconvenience those in a rush, but your battery will be healthier for longer.
Shorter driving range
It is estimated that in temperatures over 35 degrees Celsius, the EV range drops by 15%. This is because the battery is busy keeping itself cool. With this extra energy being used, there is less to go around the rest of the car - much like in cold temperatures.
Tyre pressure buildup
Air expands in hot temperatures, which is bad news for your tyres. Too much tyre pressure can lead to more battery energy usage for different reasons.
Pressure buildup in tyres leads to less grip, making the EV work harder to drive forward. As well as this, suspension needs to work extra hard to absorb shocks. A study found that controlling tyre pressure gives EVs a further driving range.
There is also a big safety risk with having too much tyre pressure. With reduced grip, the chance of skidding is increased, and braking distance is slower.
EV battery types and weather impact
The way temperatures affect your EV depends on the battery. There are two main types, lithium-ion and solid-state. The differences in reactions stem from the chemical and physical way they work.
Let’s look at each of these EV batteries and how they are affected by the climate.
Lithium-ion batteries
Lithium-ion is the most popular type of EV battery and is sensitive to low and high temperatures. They contain a liquid known as electrolyte, which has the job of carrying an electric charge.
In hot temperatures, the electrolyte degrades, reducing driving range and shortening the battery life. Then, lithium-ion batteries produce less energy when the temperature drops and are worse at holding charge.
Solid-state batteries
Solid-state batteries are better equipped for dealing with extreme temperatures. This is due to them being made of solid electrolyte instead of liquid. Issues that the lithium-ion battery faces, such as capacity loss and reduced range, are not as common in solid-state ones.
However, in cold weather, solid-state batteries still face some issues, including slower charging and reduced range. This is because the low temperatures affect the solid electrolyte’s conductivity, making it move slower.
Does weather affect hybrid vehicles?
Hybrid vehicles combine an electric and internal combustion engine (ICE). They are great for those who want the best of both worlds but still face issues due to the weather. In fact, in cold weather, hybrid vehicles show a 34% drop in fuel efficiency.
Even though they have an ICE to remove some stress from the electric battery, hybrid vehicles still suffer from sluggish energy use. To make up for this, petrol or diesel is used to heat the vehicle and keep it working, using up more fuel than usual.
Switching back and forth between gasoline and electric can make hybrid vehicles slower and less energy efficient. This reduces the distance they can travel and impacts the lifespan of the battery over a long period of time.
What owners can do to climate-proof their EVs
Even though you can’t control the weather, some things can be done to protect EVs from the negative effects. With simple changes, you’ll see a noticeable improvement in range, capacity, and charging time.
Turn on eco mode
EVs have an ‘eco mode’, reducing the energy the car uses. This helps with travelling long distances on one charge by only using energy where completely necessary. Eco mode prioritises energy in other ways by adjusting settings such as:
throttle response
climate control
lighting
suspension
Use regenerative braking
There is a feature EVs have that generates energy for the battery whenever you use the brakes. It works by capturing the energy usually lost during braking and changing it into electricity to be used later. By saving energy, you will have a further driving range in hot and cold weather.
Keep the battery charged
Because they aren’t as efficient at charging in cold temperatures, ensuring your battery is at full capacity at all times is ideal. Start every commute or road trip with a full battery to avoid the effects of cold weather on its efficiency.
Also, having a full charge ensures you have enough power for driving in weather conditions such as rain, wind, and snow. It is especially important in this case as this type of driving consumes a lot of energy.
Check tyres
Even your tyres can impact the efficiency of the EV battery, which becomes especially clear in harsh weather. You must also check tyres often for safety reasons to ensure no blowouts, balding, or punctures.
Keeping tyres full with the right amount of air saves energy in cold and warm temperatures. In cold weather, tyres tend to become deflates, while they expand in hot weather, both requiring more energy to move.
Use protective covering
If your EV is parked outside, keeping it covered in harsh temperatures helps to insulate it from temperature changes. Staying outside in the winter for a long time damages the battery and impacts its charging speed and capacity. On the other hand, hot temperatures in the summer lead to overheating.
The next steps in climate-proofing EVs
As EVs become more popular, so does the push for these weather-related issues to be fixed. Even though there are steps drivers can take to soften the impact temperature has on their EVs, it only goes so far. Fortunately, vehicle manufacturers are on a continuous mission to make technology better.
Here are some of the newest breakthroughs that will improve EV performance in all weather temperatures.
New battery cooling technology
To cool down, EV batteries previously used a passive cooling technique. This meant that cold air from the outside was circulated around the battery to keep it from overheating.
However, this method wasn’t effective and caused batteries to worsen over time and stop working altogether. In reaction to this, those who bought Nissan’s EV Leaf model sued the company in 2012, stating they were lied to about how far it could travel on a single charge.
This was a turning point in the EV industry, and now battery cooling technology uses an active approach. Coolant fluids, pumps, and fans inside the vehicle control the battery’s temperature. This has proven more effective and can be done when the car is parked.
Fast charging in all weather
For fast charging and full battery capacity in all weather conditions, Chinese company Greater Bay Technology designed the Phoenix cell battery. They guarantee a full charge in just six minutes. No matter the weather, the battery’s performance will not be affected.
They did this using special materials and thermal management to make freezing temperatures warmer and safer for the battery.
Saving energy with heat pumps
To save energy in cold weather, car manufacturers Hyundai and Kia designed a heat pump and demonstrated it in the Kona Electric model. It was originally made six years ago but has not been successful until now.
It gets energy by recycling extra heat from different car parts, such as battery packs and modules. This heat is turned into gas, then liquid which warms up the cabin, leaving less work for the air conditioning to do.
Final thoughts
Not being able to drive long distances is already the main reason people hesitate to use EVs. Because of this, it’s important that improvements are made to EVs to make them better withstand hot and cold temperatures.
There are things drivers can do to help, including using eco mode and regenerative braking, but the power lies in the hands of manufacturers. Batteries are getting more advanced but still face struggles with range, capacity, and efficiency due to weather.
By conquering these problems, manufacturers can make EVs appealing, encouraging more adoption across all seasons, from scorching summers to icy winters.