Linking key features of commercial lithium-ion cells to thermal runaway effects

Predicting the thermal runaway (TR) characteristics of lithium-ion battery (LIB) cells based on easily accessible key cell features — such as i) cell format, ii) cathode type, iii) cell capacity and/or energy, and iv) state of charge (SOC) — would be highly beneficial. Herein, 10 different commercial LIB-cell types with four cathode variations were tested at various SOCs in both single cell and propagation scenarios, totaling 170+ abuse tests. The TR-effects, including onset temperature, maximum cell temperature, emitted gas volume, and maximum overpressure, are analyzed as functions of the key cell features. Two cathode-based groups emerge: (A) lithium manganese cobalt oxide (NMC), lithium cobalt oxide (LCO) and lithium nickel cobalt aluminum oxide (NCA), and (B) lithium iron phosphate (LFP). Intriguingly, the gas volume emitted from group (A) scales linearly with the SOC-dependent cell energy (0.46 L Wh −1 ) regardless of the test atmosphere. TR-propagation tests show that NMC/LCO/NCA cells propagate at 70–100% SOC but typically not at 30%, with propagation classified as non-, slow-, or fast-propagating. Overall, the results indicate that TR-effects of specific LIB-cells may be predictable based on key cell features, improving mechanistic understanding and enabling the development of advanced safety measures.