Passive Thermal Management in Lithium-Ion Battery Systems via Multilayered Phase Change Materials

Abstract

With the emerging presence of lithium-ion batteries in aerospace vehicle applications, weight, volume, and safety of lithium-ion battery packs must be addressed with renewed concernment. A thermal runaway event of a single cell can generate temperatures exceeding 600°C, potentially destroying the entire battery pack along with sensitive equipment critical to vehicle operations. If thermal runaway could be contained to a single cell, it would substantially reduce the risk of damage to the vehicle, potentially enabling mission operations to continue. Due to their relatively low mass, low thermal conductivity, versatile formability, and high heat absorption properties, phase change materials (PCM) are a strong candidate for engineering thermal management into lithium-ion battery packs. Herein, seven PCM-based pads, enhanced by novel flame-retardant and intumescent coatings, are evaluated for their ability to prevent thermal runaway propagation. Thermal runaway is initiated via nail penetration in modules of three 11.7Ah, pouch format, NMC lithium-ion cells at 100% SOC, with a pad between each cell. Computational models of the pad samples are developed based on the experimental data, and are also presented in this work.