Modular phase change material (PCM) thermal management systems for cylindrical li-ion cells

Sufficient thermal management is required for lithium-ion batteries to ensure prolonged battery life, optimal ionic reactions and to prevent thermal runaways. Thus, a majority of battery pack manufacturers utilize thermal management systems consisting of either air or coolant-based circuits to reduce the batteries operating temperature. However, such systems require active components including pumps and fans which increase operating costs. As such, phase change materials (PCM) based cooling systems are attractive alternatives due to the system’s ability to dissipate heat passively and its high latent heat capacity. Nonetheless, there are several challenges in implementing such a system for commercial usage including the encapsulation of the PCM material, enhancement of the PCM’s thermal conductivity and the optimal volume requirements of the system. With such requirements in mind, this paper introduces a modular honeycomb based PCM cooling system enhanced with aluminum fins. The modular aspect of the design involves both triangular slots and protrusions that allow the system to be attached to each other. Paraffin is used as the PCM material due to its non-corrosive nature and its similarity in melting point with the optimal operating temperature of the battery. Volume optimization of the system is parameterized through the computational fluid dynamics (CFD) software and its corresponding temperature reduction is observed. Results from the study display a significant temperature reduction in the batteries maximum temperature, however further experimentation is required to validate the accuracy of the results.