How to cool the electric car?

Usually, the most cooling part of an electric car is the battery. When you discharge and take energy out of it, it generates heat. The faster the battery discharges, the hotter it becomes. The same is true of the story of battery charging. The hotter they get, the shorter their life span. That's why batteries are usually closely monitored and managed by the Battery Management System (BMS), if your car has one. If batteries become too hot, they will damage themselves, and they will reduce and lose scope. Battery management system is designed to keep the battery at the optimum temperature between 68 F and 104 F (20 C to 40 C). Coolants can also be used to cool batteries in some cars, which are operated by BMS. Vehicles that do not use coolant cooling batteries have an air-cooled system (passive system), such as Nissan Leaf. Whether this passive cooling is sufficient to properly cool the battery to a better temperature remains to be seen, and may lead to longer-term deterioration of the battery compared with controlled and monitored coolant systems.


You may notice that some automobile manufacturers design electric cars with grilles in the front of the car. This is usually part of the design process of an internal combustion engine (ICE) car because the engine becomes very hot and the cooling air is pushed through the front of the grille as it travels. This is not necessary for electric vehicles, because the motor will not reach very high temperature compared with ICE engines. Vehicles without BMS, such as Nissan, use air to cool their batteries while driving. In this design, air below the vehicle helps to cool the batteries. The design of the grille is entirely done by the designer, but the fact is that the use of the grille will reduce the aerodynamic efficiency of the car, which means that it needs more energy to move. This front grille look is something we have become accustomed to in the car experience, and as time goes on, you will see fewer and fewer things. Efficiency is now the goal of electric car games, you can get more efficiency through batteries.


Motors do need coolant to cool them, but because of the efficiency of the motor, it produces a very small amount of heat compared with ICE. ICE can generate more than 1,300 F (700 C) of heat, which is very useful in winter when you can use the excess heat of your internal car to heat passengers. However, if you drive in the summer and don't need heating, then efficiency and practicality will be much lower.


In Tesla, there is a real need to cool the computer inside the car. The electronic equipment generates a lot of heat. The central console is connected to the dashboard to make it well insulated. Another way to cool a car's internal computer can be air conditioning. With a fail-safe feature, if Tesla is shielded from the sun when away from the car, the air conditioner will automatically turn on and lower the temperature to keep the computer at a reasonable temperature and avoid damaging electronic products.

Will electric cars overheat?

Usually, electric vehicles overheat, reduce engine power, and eventually shut down when they overheat. This is a way to protect cars from permanent damage, and faster battery release also generates more heat. This means that the faster you go, or if you speed up a lot, you will release the battery faster than normal. When charging an electric car, the charging rate is the same, and the batteries start to heat up a lot. Reducing the speed at which you charge your car will lower the temperature of the battery. If your car has a BMS, the possibility of overheating the battery will be greatly reduced, because the onboard computer can monitor and prevent this from happening.

What happens if the battery of an electric car overheats?

Usually, in the battery pack, there are all kinds of modules connected together. If some modules have much more heat than other modules, it may lead to a decline in battery performance, which means that the battery has a smaller range of power. Because of the overheating of batteries, there will also be fires, usually some kind of small explosion, followed by fires. Fire departments must receive special training to deal with battery fires in electric vehicles. Overheating of batteries can also lead to different charging speeds and discharge speeds in batteries. When all battery modules are charged or discharged at the same speed, the battery works best, so no battery pack works harder than the other.

Tesla cooling system

Tesla uses pipes filled with propylene glycol to cool batteries, electronics and motors. This is to use pumps to circulate throughout the car and prevent overheating of important parts of the car. Tesla uses a patented serpentine cooling system in its battery pack, as shown in the following figure (the coolant pipe is shown in blue). Because ethylene glycol can access all batteries, it can fully cool the batteries. Jaguar I-Pace and BMW I3 also adopt similar liquid cooling processes.

This type of liquid cooling described above can be called indirect cooling, because the liquid circulates in a pipe next to the battery. ICE cars also use pipes to help cool their engines. Another type of liquid cooling is called direct cooling, where batteries are completely immersed in liquid solutions. The liquid solution needs to be very conductive or non-conductive, so that the battery will not conduct electricity in the liquid. So far, direct cooling is not only realized in the laboratory environment, but also can be implemented in the industry. Compared with indirect solutions, direct cooling is more effective in cooling batteries.