Properties enhancement of phase-change materials via silica and Al honeycomb panels for the thermal management of LiFeO4 batteries

A novel form-stable composite phase-change material (CPCM) is introduced that features a paraffin wax (PW) and expanded graphite (EG)-based battery thermal management system (BTMS) with additional silica gel and Al-honeycomb (Al-Hc) components. The properties of the CPCM were analyzed in terms of their crystallographic structure, heat transfer capacities, and stress-strain response. The CPCM was applied to a BTMS to determine the temperature response of a battery and the CPCM surface. The results showed that immersing PW/EG CPCM in silica gel could prevent the leakage of liquid PW from a PW/EG CPCM via an encapsulation effect. The degree of super-cooling in a PW/EG/SiO2 CPCM saw reductions of 33% and 21% relative to the super-cooling values of PW PCM and PW/EG CPCM, respectively. This composite also exhibited superior mechanical properties and a lack of surface cracking and deformation after compression testing. It also has a high heat-dissipation efficiency, which was attributed to the presence of the Al-Hc. Lastly, the PW/EG/SiO2/Al-Hc CPCM exhibited excellent thermal management performance when applied to LiFeO4 scenarios, maintaining the operating temperatures well within the 50 °C maximum of the safe and efficient battery operation range.