Comprehensive experimental research on wrapping materials influences on the thermal runaway of lithium-ion batteries

This study investigates the effectiveness of different wrapping materials, namely aerogel felt, thermal conductive gel, and two phase change materials (PCMs) in mitigating thermal runaway in lithium-ion batteries. The experimental results reveal that all the materials tested delay the onset of thermal runaway and safety valve rupture compared to unwrapped batteries. Specifically, aerogel felt and thermal conductive gel offer substantial thermal runaway inhibition, delaying the safety valve rupture time by 97 and 99 s, respectively. PCM-1 demonstrates a delay in safety valve rupture but has a limited impact on the onset of thermal runaway. Among all materials, thermal conductive gel shows the most significant impact, postponing both safety valve rupture and thermal runaway onset. In contrast, the PCMs exhibit relatively weaker effects. Furthermore, batteries wrapped in aerogel felt produce the highest CO concentration during thermal runaway, reaching 3,658 ppm. The maximum mass loss rate of the batteries varies with the wrapping material, ranging from 20.1 to 68.5 g/s, with the unwrapped batteries exhibiting the highest loss rate. Overall, the results suggest that thermal conductive gels and phase change materials improve the safety and emergency response of lithium-ion batteries under extreme conditions, with the thermal conductive gel showing the most promising results in delaying both safety valve rupture and thermal runaway.