Cooperative Effect of Integrating Active Thermal Management With Passive Thermal Insulation for Enhanced Thermal Runaway Suppression in Large-Format Batteries

Abstract

This study introduces a hybrid thermal management system integrating active thermal management with passive thermal insulation (ATM&PTI). By combining liquid cooling, a micro heat pipe array (MHPA), and an aerogel insulation layer, the system enhances heat dissipation during normal operation and suppresses thermal runaway (TR) propagation under abuse conditions in large-format lithium-ion battery modules. A full-scale 3D multiphysics model was developed and experimentally validated to investigate TR initiation and propagation in a four-cell 300 Ah LiFePO₄ battery module under different thermal management configurations. Results show that liquid cooling delays TR onset but cannot prevent propagation, whereas the aerogel barrier blocks propagation but advances TR initiation. The proposed ATM&PTI architecture synergistically enhances axial heat extraction and lateral thermal isolation, delaying TR onset to 7108 s and achieving complete propagation suppression. Sensitivity analyses further define the safe-operating design window: for a 3 mm barrier, the critical thermal conductivity and coolant flow rate required to block propagation are 0.07 W m⁻¹ K⁻¹ and 175 mL/min, respectively. This work provides practical guidance for developing intrinsically safe large-scale energy storage systems.