A novel thermal-cloak-based thermal design for preventing thermal runaway propagation in lithium-ion battery packs

Thermal runaway is a major safety issue for lithium-ion battery packs during manufacturing, storage, and service. Designing a more efficient thermal structure to prevent the propagation of thermal runaway is crucial for ensuring the safety and performance of the lithium-ion battery packs. In this work, a novel thermal-cloak-based thermal design with the phase change material for preventing thermal runaway propagation in lithium-ion battery packs is proposed. In this new design inspired by thermal cloak, a single battery is wrapped with two layers of materials. The inner layer in contact with the battery surface uses phase change materials (paraffin or hydrogel materials) to control the operating temperature range of the battery, and the outer layer employs materials with high thermal conductivity (aluminum or copper) to efficiently dissipate heat and prevent local high temperatures. The results show that the maximum temperature of the battery with paraffin and hydrogel materials is 99.92 °C and 92.7 °C, respectively, when only phase change materials are used. After adopting the thermal-cloak-based thermal design, the maximum temperature of the battery decreases to 57.25 °C, demonstrating the advantage of the new design for preventing thermal runaway propagation. Moreover, the effectiveness of this thermal design in preventing thermal runaway propagation has been validated through numerical simulations and experimental testing. In addition, the new thermal design improves temperature uniformity in the battery packs. The thermal design proposed here can avoid thermal accumulation and high temperature gradients, which may help improve the safety of lithium-ion battery storage, transportation, and operation. The research findings of this work provide a fundamental understanding of preventing thermal runaway propagation and may improve the performance and safety of energy conversion and storage systems based on lithium-ion battery packs.