September 18, 2025
Exactly — cooling the battery pack is one of the most critical functions in an EV, since lithium-ion batteries must stay within a narrow temperature window to operate safely and efficiently. Here’s a breakdown of the main battery cooling options you mentioned:
How it works: The material absorbs heat as it changes from solid to liquid (latent heat storage).
Advantages:
Passive system, no moving parts.
Can smooth out temperature spikes.
Limitations:
Heat absorption capacity is limited once the material has fully changed state.
Often used in combination with other cooling methods.
How it works: Thin metal fins increase the surface area of the battery pack or module, allowing more efficient heat dissipation into surrounding air.
Advantages:
Simple, lightweight, and low cost.
Works well with natural or forced air cooling.
Limitations:
Air has low thermal conductivity compared to liquids.
Not sufficient for high-performance or high-capacity battery packs.
Passive air cooling: Relies on natural convection around the battery.
Active air cooling: Uses fans or ducts to blow air through the pack.
Examples: Early Nissan Leaf models used air cooling.
Advantages:
Low complexity and cost.
Lightweight system.
Limitations:
Poor heat transfer efficiency.
Limited effectiveness in hot climates or under heavy loads.
How it works: Circulates coolant (often a water-glycol mixture) through channels, pipes, or cold plates in contact with battery modules.
Examples: Tesla, BMW, and most modern EVs use liquid cooling.
Advantages:
High thermal conductivity and very effective at heat management.
Can integrate with the vehicle’s overall thermal management system (shared with motor, inverter, AC/heat pump).
Limitations:
More complex and heavier than air systems.
Risk of leaks.
Summary:
Phase change materials: absorb heat temporarily, best as a supplemental method.
Cooling fins and air cooling: simple but limited, suitable for lower-power EVs.
Liquid cooling: the most effective and widely adopted method for modern EVs, especially high-performance and long-range models.
