Battery Thermal Management using Phase Change Materials

Abstract

The rising adoption of lithium-ion batteries in electric vehicles (EVs), portable electronics, and renewable energy systems has elevated the importance of efficient Battery Thermal Management Systems (BTMS). Excessive heat generation during charge/discharge cycles degrades battery life, reduces performance, and poses safety risks such as thermal runaway. Among various BTMS technologies, Phase Change Materials (PCMs) have emerged as an effective passive cooling solution due to their high latent heat capacity and ability to absorb excess thermal energy during phase transitions. This study explores the principles and applications of PCM-based thermal management systems for batteries, focusing on how different PCM types, composite materials, and system configurations influence heat dissipation and temperature control. Pure paraffin waxes, although widely used for their high latent heat, suffer from low thermal conductivity and leakage during melting. Researchers have developed PCM composites enhanced with expanded graphite, metal foams, carbon nanotubes, and graphene to address these limitations. For example, the incorporation of copper foam or expanded graphite into paraffin matrices has shown significant improvement in heat transfer and thermal response time. Experimental studies and multiscale simulations prior to 2020 reveal that PCM-enhanced systems can limit temperature rise in battery cells by over 20–30% compared to passive air cooling alone. Further, shape-stabilized PCMs and encapsulated designs minimize leakage and improve durability across multiple thermal cycles. While PCMs do not require additional energy to operate, they often lack the ability to remove heat continuously, necessitating hybrid systems or recharging mechanisms. This paper synthesizes key findings on PCM selection, integration methods, and thermal modeling, and outlines their comparative advantages in real-world battery applications.