A novel hybrid thermal management for Li-ion batteries using phase change materials embedded in copper foams combined with forced-air convection

Abstract

In the present study, a newly designed thermal management system (TMS) was introduced for pouch lithium-ion battery (LIB) modules with a focus on stressful conditions. Paraffin, as a PCM with large heat storage capacity, was embedded in a copper foam integrated with a heat-sink air cooling. The module exhibits excellent thermal performance for the battery pack, especially for a longer working time at an appropriate temperature range. The battery surrogate was employed to emulate heat generated by LIB at high constant current discharging and onset of thermal runaway conditions. The tests carried out under various Reynolds numbers indicated that at the airspeed of 3.2 km h−1, the temperature at high rate discharging is being maintained in steady state below the 60 °C limit. In addition, the copper foam with high thermal conductivity played a leading role in transporting the heat promptly and making a uniform temperature distribution. The comparison of the hybrid (H) TMS with the passive and active TMSs shows that although the active forced air convection reached a steady state below the safety temperature at the ambient conditions (24 °C), both active and passive systems were inefficient in hot weather (40 °C). Similar results were achieved for the onset of thermal runaway, which showed that HTMS could use 76.7% and 100% of the heat-sink and PCM latent heat capacity compared to active and passive, respectively, while passive could use only 13% of the PCM heat storage capacity. It could be concluded that the method of combining active and passive parts plays a vital role in HTMS design.