Thermal Runaway Characteristics of Batteries with Manganese-Based Composite Cathode Materials Triggered by Electromagnetic Induction Heating and Lateral Heating

Trigger selection underpins thermal runaway (TR) and thermal propagation (TP) testing of lithium-ion batteries, yet its influence on the TR response is rarely quantified, and data for a cell with manganese-based composite cathode (MCC) material are scarce. Here, a fully charged 130 Ah prismatic cell using MCC was driven into TR by high-frequency electromagnetic induction heating and by lateral plate heating in identical fixtures, and each response was resolved into four stages. A 12-s induction pulse initiated TR from a local nucleus: flame ejection followed venting by 9 s, the trigger-point temperature peaked at 682.6 °C, and the voltage collapsed in two stages with a ~3.0-V, ~14-s plateau, the signature of an expanding local short circuit. Lateral heating required 273 s of whole-cell preheating and produced a faster, hotter event: a jet flame ~20 s after venting, whole-cell involvement within 10.4 s, a 775.4 °C peak, and a single-stage ~20-s collapse. Induction heating thus provides rapid, position-selectable initiation with minimal additional energy input, which is well suited to propagation testing, whereas standard-compliant lateral heating represents external-fire abuse; these results provide the first cell-level reference data for MCC thermal runaway, quantify how the triggering method alone alters the TR response, and identify the voltage-collapse morphology as a diagnostic of the initiation mode.