Can An Electric Car Overheat? Here Are The Facts


Summertime is a great time for road trips, vacationing, and adventuring. It is also a time when temperatures in a lot of places get really high. Why someone would live in such a place is the topic for a different article on a very different website, but here we will talk about the heat versus electric vehicles. We already know that vehicles with gas or diesel engines can overheat during the summer and that can be a big problem.

Can an electric car overheat? Yes, an electric car can overheat. Heat is generated in a battery pack both during discharge and recharging. If the integrated battery pack cooling system malfunctions, or cannot adequately deal with the external temperatures present, then the electric car will overheat. Any warning light for overheating in an EV should be immediately adhered to. 

This seems to be one of the few mechanical issues when it comes to electric cars. But to new electric car owners, this may seem daunting. But in this article, we will inform you about how it happens, and how to prevent it.

Can An Electric Car Overheat?

All batteries rely on a chemical reaction to cause electrons to flow. No matter the battery type, this chemical reaction generates heat. Under different conditions, this heat can be dangerously high. Since electric vehicles rely on a large battery, heat will certainly be generated.

Aside from normal operations, there is always the chance that things can break down and cause issues. There have been a lot of worries and a few incidences of the lithium batteries in electric vehicles spontaneously combusting. While this is fairly uncommon and unlikely to happen, it is always frightening to hear about. Fortunately, technology is advancing and greater measures are being taken to protect the safety of electric vehicle owners. The only real anxiety EV drivers should be facing is the dreaded “range anxiety” that comes from asking, “Will I make it to the next Tesla Supercharger?”

Why Does It Happen?

Whether a battery is charging or discharging, it’s going to generate some heat. The flow of electrons faces some resistance, however slight, and that generates heat. The metal of the wires, motors, and so on, conduct that heat. The insulation of the wiring does keep the heat trapped, but beyond that, the heat can’t naturally escape up or down. Since the batteries, motors, wheels, brakes, and anything else that could generate heat is below the cabin of the vehicle, the heat is reflected in part back down to the heat source. This compounds the heat and if left unchecked, bad things could happen.

Likewise, heat is not directly going to escape under the vehicle. First off, heat tends to rise, so it’s already dispositioned in the wrong direction. Second, these cars are pretty low to the ground and offer less airflow to carry away the heat. Finally, on an especially hot day, the pavement will be hot as well and that heat will be rising upward into the bottom of the vehicle. 

Of course, this is a bit of hyperbole only to demonstrate how things can heat up in and around the battery and vehicle overall. In the next section, we will go through systems designed to cool things down as well as driver habits to follow to limit overheating.

How Do I Prevent Overheating?

Fortunately, manufacturers and engineers have developed battery cooling systems that almost entirely prevent overheating. Much like cars with internal combustion engines, these cooling systems utilize a coolant that gets pumped past the battery. This liquid absorbs the heat of the battery and is then pumped through a heat exchanger or radiator. Ambient air moves through the fins of the radiator and draws the heat away. The now cooled fluid once again cycles past the battery to absorb more heat. This constant flow does a great job of keeping the battery at a cool temperature. 

Another system implemented to cool the batteries is a heat pump system. This is similar to the liquid cooling system, but it is actually more like an AC unit. A refrigerant is decompressed allowing the particles to absorb heat. The fluid is pumped through a heat exchanger where the heat of the battery is disposed of outside the vehicle. This system is a bit more slender and is equally as effective as the liquid cooling system.

Everyone’s favorite electric vehicle, the Tesla, has an interesting design for cooling the battery. Imagine the huge electric vehicle battery. If you can’t, you can find it all over google. Within this huge, shiny battery are smaller, less shiny battery cells. In between those cells runs a system of fluid lines that capture that pesky extra heat from the battery cells. That fluid gets circulated and cooled and makes for an effective cooling system.

Likewise, there are electronic control systems in place that limit the use of the vehicle in an effort to prevent overheating. How they exactly function can be a bit complicated, but it is sufficient to know that the computer is programmed to detect rising temperatures and alter the driveability of the vehicle in order to prevent overheating.

Aside from these built-in systems, there are a few operator errors that can cause overheating. The first relates to geographical location. If you live in areas that are generally hotter, such as California, Nevada, or other southern states, the chances of overheating are already raised. Parking in the shade, driving when it’s less hot, or moving away are a few options to consider.

Second, charging raises the temperature of the battery, so take care where you charge and how often you charge. Once again, there are built-in limiters so that the battery will not over-charge, but during normal charging, heat will be present. Most manufacturers recommend charging indoors to limit the exposure to ambient heat. Some models will turn on an internal fan that will help cool the charging process. 

Finally, driving habits will affect the temperature of the battery. This isn’t really a novel idea since the same thing happens to cars with internal combustion engines. They call it “hot-rodding” for a reason: things get hot. Driving an electric vehicle aggressively will do the same thing as the battery is experiencing a sustained high output. To prevent that, be easy on the throttle and take a break at about 100 miles of constant driving. 

What To Do If Your Electric Vehicle Overheats

Even after driving like a granny and parking in the shade, overheating can occur. It is important to take action when this happens because the high-voltage battery can be very dangerous. There are even some reports that overheating can cause fires, which is very serious. Even if it doesn’t get to that point, extra heat can shorten the life of your battery resulting in expensive repairs down the road.

As mentioned previously, the engineers behind these electric vehicles have developed programs within the vehicle to limit the use of the battery in high temperatures. If there is suddenly a spike in temperature in an extreme way, this indicates that something is seriously wrong with the vehicle and needs to be repaired. In cases like this, it’s best to pull over, safely assess the situation, then call for help.

If it is not an extreme case, the smart thing to do is still pretty similar. Pull in somewhere that the car can safely cool down, such as a covered garage. If this happens during the day, it might need to sit overnight to give it time to cool as well as to allow the cooler night temperatures to help out. 

Are Certain Models More Prone To Overheat?

While the technology for EVs is expanding, it’s not without its flaws. Nothing is perfect and there will always be the chance that a vehicle will overheat, some more than others. 

One such model notorious for overheating is the Nissan Leaf. Well, it is a bit unfair to pin it on such a reputation because it uses a different cooling system than most other cars. Actually, it doesn’t use a cooling system. Instead, it is designed to be cooled by the ambient air as the vehicle drives.

There is also an argument that there is a bit of cooling done by the cabin air conditioning, but it isn’t a dedicated function of the AC system. Of course, if the Leaf is driven somewhere with a moderate climate that is not too hot or humid, this system should work great. However, this isn’t always the case, especially considering EVs are becoming more and more popular in highly populated areas, such as California, which is known for being quite hot and humid. 

Aside from this model, very few other models of electric vehicles have overheating issues. As mentioned before, cooling system designs have been adapted from gasoline engine vehicles and work quite effectively. With other built-in protections against overheating, the risk is pretty low.

Conclusion

Yes, there is a risk of an electric vehicle overheating. Overheating can be caused by many different factors, including system or component malfunction, manufacturing flaws, or just poor overall design. With that being said, there are highly effective built-in systems to keep things cool and operating properly. If you find yourself in a situation where your EV is overheating, it’s time to call for help. Overheating is dangerous to the driver and passengers and can also shorten the life of the vehicle. So stay cool out there.

Recent Posts