Electric vehicles have become the future of the transport industry because of their eco-friendly nature & zero emission. But there are certain limitations when it comes to EV, such as cost, lifetime, safety, efficiency & many more. By using the proper cooling system, we can reduce some limitations and make it more efficient. In an Electric Vehicle, the primary source of heat dissipation is the battery & motor, which can be controlled up to a certain limit. So Battery cooling system in Electric Vehicles is essential for better functioning and performance of the vehicle.
TYPES OF COOLING SYSTEMS:
AIR COOLING SYSTEM:
Air cooling uses the principle of convection to transfer heat away from the battery pack. As air runs over the surface, it carries away the heat emitted by the pack. There are two types of air cooling systems PASSIVE air system & an ACTIVE air system.
An active cooling system involves the use of energy to cool something, as opposed to passive cooling that uses no energy. Such systems circulate a coolant to transfer heat from one place to another.
A passive system can produce more cooling than an active cooling system. Air cooling is simple, cost-efficient & easy. Air cooling eliminates the need for a cooling loop and any concerns about liquids leaking into the electronics. The added weight from using liquids, pumps, and tubing is also avoided. But not very efficient and relatively crude compared to liquid cooling. The air-cooling system needs 2 to 3 times more energy than other methods to keep the same average temperature.
LIQUID COOLING SYSTEM:
A liquid cooling system is an efficient way of cooling & many companies use this system for thermal management. Liquid has high heat capacity than air & can control battery pack temperature by circulating the coolant between the battery pack & the heat sink. There are two types of liquid cooling systems DIRECT contact liquid & INDIRECT contact liquid cooling system. Out of the two, the most common type of cooling is the indirect type of cooling system where the coolant is not in direct contact with the batteries which provide high safety measures & performance. Some car models like Tesla, Chevrolet use CHILL PLATES under the battery pack with circulating coolant.
In an electric vehicle, the battery is made up of clusters of independent cells that are sensitive to cold and heat. The heat produced by the battery must be dissipated while ensuring protection from external conditions. Therefore cooling systems such as air cooling systems & liquid cooling systems are used. The aim is to maintain a stable temperature, thus guaranteeing constant operation and preventing premature aging.