Cooling Systems for Battery Packs: Safeguarding Performance in Electric Vehicles

The Importance of Temperature Control
Battery packs are the core of electric vehicles (EVs), and their performance and lifespan are highly sensitive to temperature. During operation, batteries generate heat—excessive heat leads to capacity loss, accelerates aging, and can even trigger safety risks such as thermal runaway. Therefore, efficient cooling systems are essential to maintain battery packs within the optimal temperature range of 20–40°C.

Main Cooling Technologies in EVs
Three primary cooling methods dominate current EV designs. Air cooling, the simplest and most cost-effective option, relies on fans to circulate air through battery modules. While suitable for low-power scenarios, it performs poorly in high-load operations or hot climates due to limited heat dissipation efficiency.
Liquid cooling, on the other hand, circulates coolants (such as ethylene glycol mixtures) through channels adjacent to battery cells. With 5–10 times higher heat transfer efficiency than air cooling, it is widely adopted in high-performance EVs, although it requires more complex pipelines and pumps.
Phase change material (PCM) cooling is a newer approach, where PCMs absorb heat by melting at specific temperatures and release it upon solidification. This passive system reduces energy consumption but requires auxiliary heating in cold environments.

Design Priorities for Effective Cooling
When developing cooling systems, two key factors must be considered. First, uniform temperature distribution is critical to avoid “hot spots” that can damage individual cells. Second, energy efficiency is essential, as the cooling system itself should not excessively drain battery power.

Future Trends in Battery Cooling
The next generation of EV cooling technologies focuses on deeper integration with battery management systems (BMS), enabling real-time temperature monitoring and control. Direct liquid cooling, which positions coolants closer to battery cells, is also gaining attention for its superior ability to remove heat quickly and maintain stability in high-energy-density batteries.

Conclusion
Cooling systems are indispensable for unlocking the full potential of EV battery packs. As battery energy density continues to rise, advancing cooling technologies will remain a crucial driver of reliability, safety, and performance in electric vehicles.