What Methods Are Used for Thermal Management of EV Batteries?

Thermal management has always been important in electronics. As electric vehicles advance from a niche market to mainstream adoption, the importance of heat dissipation in EV batteries is paramount. During operation, the battery creates a lot of heat but needs to remain within a narrow heat range for optimal performance. Transferring heat away from the battery and keeping the temperature of the battery stable is the focus of thermal management.

In examining the methods used for thermal management, three key factors should be considered: increasing power density in EV batteries, advantages of weight reduction in EVs and shrinking of electric designs.

Power Density

One of the largest barriers to entry for EVs compared to combustion engines is the range of the battery. Every manufacturer develops a comprehensive battery thermal management system. These systems include both active and passive cooling methods. Utilizing thermoelectric cooling, air cooling and liquid cooling, heat dissipates from the battery during operation.

These battery management systems will continue to develop, but for battery pack engineers, the primary focus is power density. Increasing performance while reducing overall volume of battery packs results in better performance. This increased energy density demands thermal management solutions.

Weight Reduction

Battery pack designs must balance thermal requirements with package space and mass. Compare candidate materials using the intended assembly geometry and production process. The effect on pack weight depends on the material, the interface dimensions and the amount applied.

Shrinking of Electric Designs

All designs and device housings are becoming more compact. Densely packed circuit boards and higher powered components challenge thermal management. Heat not only reduces performance but adversely affects the lifespan of electronics.

Active cooling and passive heat-transfer components

EV battery thermal management combines a cooling method with materials that help heat cross interfaces.

Active cooling

Forced-air systems use fans to move air. Liquid-cooling systems carry heat from a cold plate into coolant and toward a heat exchanger. Evaluate the cooling architecture against the pack’s heat load and operating requirements.

Passive heat-transfer components

Heat sinks and heat spreaders provide paths for heat to move through an assembly. Thermal interface materials help bridge the contact between a heat source and a cooling surface. These materials support the cooling system.

Selecting a battery-to-cold-plate gap filler

Compare pads and two-part dispensables against gap variation, assembly pressure, electrical-isolation requirements, service needs and application process. Evaluate the selected material at the intended interface thickness and operating conditions. Weight and thermal performance depend on the material and assembly. Explore P-THERM® gap fillers or discuss your battery interface with Polymer Science.