Quantification of Lithium Battery Fires in Internal\nShort Circuit

Single-layer\ninternal shorting in a multilayer battery is widely\nconsidered among the “worst-case” failure scenarios\nleading to thermal runaway and fires. We report a highly reproducible\nmethod to quantify the onset of fire/smoke during internal short circuiting\n(ISC) of lithium-ion batteries (LiBs) and anode-free batteries. We\nunveil that lithium metal batteries (LMBs) with or without liquid\nelectrolytes are more dangerous than LiBs upon internal shorting,\nigniting fires within a time scale of 1–3 s followed by similar\nor larger combustion heat release. This implies that all solid state\nbatteries (ASSBs) with lithium anodes will have safety concerns, and\nmuch research is needed to scrutinize ASSB safety. Also, there exists\na threshold in the shorting current to trigger a fire in LMBs, and\nits precise control is key to reproducing ISC behaviors. Finally,\nwe unravel the profound role of oxygen in fire/smoke formation and\npresent new suggestions for developing safe ASSBs.