Design of a multilayer flame arrestor for lithium-ion batteries and investigation of the thermal-runaway flame suppression mechanism

With the rapid adoption of lithium-ion batteries (LIBs) in energy-storage and transportation systems, increasingly complex operating conditions heighten the fire and explosion hazards of thermal runaway (TR). To suppress its early flame spread and provide effective early rescue time, in this study, a multilayer perforated-plate flame arrester was designed. GC–MS was employed to analyze battery-generated gases and Fluent simulations of jet-flame velocity are used to determine arrestor parameters, and the structure is optimized via the throttling effect. Experimental verification is conducted thereafter. The results show that the gaseous products primarily consist of CO₂, CO, H₂, and C₂H₄, with total yields of 3.23 mol and 4.8 mol for cells at 75% and 100% state of charge (SOC), respectively. The simulated peak flame velocity of the ejected gases reaches 21.53 m/s. Considering manufacturing constraints and cost, a single-layer quenching plate with an aperture of 0.4 mm, a pitch of 0.3 mm, and a thickness of 0.8 mm was selected, giving a maximum quenching velocity of 4.86 m/s for one layer. Based on the throttling effect, a multilayer quenching-plate structure was designed; simulations indicate that three layers reduce the flame velocity to 4.53 m/s, while six layers reduce it further to 3.57 m/s. Experimental results confirm that the flame arrestor effectively suppresses both flames and sparks. Under the front-facing configuration, 75% SOC and 100% SOC conditions require five and seven layers, respectively; under the side-facing configuration, only three layers are required, and spark emission decreases with increasing numbers of quenching layers.