In-situ monitoring of multiple signals evolution behaviour for commercial lithium-ion batteries during internal short circuit

Internal short circuit in lithium-ion batteries is a crucial hazard threatening. It is accurately difficult to monitor the internal signals in time of the lithium-ion batteries during the process of internal short circuit. Herein, a novel method is developed to monitor multiple signal evolution behaviour using a sealed tank and sensors. The internal signals of LFP batteries and NMC batteries exhibit different evolution behaviours, especially in the response sequence of pressure and gas. Battery capacity has an impact on ISC signal response sequence and time for LFP batteries, showing identical sequence and shorter time with the increase of capacity. The voltage and temperature are considered as sensitive signals for both LFP and NMC811 batteries that sensitive signals are defined based on their response speed. This operando technique provides a suitable platform for understanding the side reaction mechanism during thermal runaway in commercial LIBs.