Experimental and numerical investigation of 3D-printed macro-encapsulated PCM variants for battery thermal management systems

Abstract

This study presents a novel battery thermal management system (BTMS) design, which is numerically and experimentally examined, utilizing macro-encapsulation with 3D-printed polylactic acid (PLA) material to store phase change materials (PCM). A distinctive contribution of this study is the implementation of macroencapsulated PCM using 3D printing, which offers a leak-proof, passive, and energy-free BTMS solution. This approach addresses sealing issues and improves battery thermal management. Capric acid (CA) and microencapsulated PCM (ME) are compared to the base case with an air gap under different charge and discharge conditions. The high specific heat capacity and phase change temperature of CA-PCM enable effective battery thermal management. The BTMS effectively maintains battery temperatures within the optimal range, extending battery life. Under all charging and discharging conditions, battery temperatures in CA-BTMS are consistently lower than those in Air BTMS. The CA BTMS temperature is 37.83 degrees C in the 1.72C charging condition, compared to 38.09 degrees C in the Air BTMS system. Similarly, the CA BTMS battery temperature is 36.18 degrees C under the same Crate discharge condition, whereas the Air BTMS temperature is 36.39 degrees C. Reduced internal resistance in the CA case enhances voltage stability and energy efficiency, yielding higher average voltage values during charge and discharge cycles. CA BTMS exhibits lower voltage differences during charging than Air BTMS, and these differences are further reduced to 0.019 V, 0.012 V, and 0.01 V during discharge.