摘要:SummarySafety issue of lithium-ion batteries (LIBs) is always a concern. We have studied the inhabitation on thermal runaway (TR) and propagation of 18,650 LIBs in an enclosed space systematically. LIBs at 70% state of charge are chosen for testing. Four fire extinguishing agents are applied on LIB arrays for 20 s, and the inhibiting effects are different. The cooling efficiency varies with the surface temperatures of LIBs. Water spray has the highest cooling efficiency and inhibits the TR propagation among LIB arrays successfully. Three LIBs undergo TR for the releasing of ABC ultrafine dry powder. BC ultrafine dry powder and Novec 1230 are failed to inhibit the TR propagation. Nevertheless, Novec 1230 shows the best on inhibiting fire occurring and the generation of toxic gas. Generally, this study provides valuable information for the choice of fire extinguishing agents.Graphical abstractDisplay OmittedHighlights•A comparative study was done on the inhibition effects of four suppressants•LIBs at 70% SOC had the best thermal runaway propagation ability•Water had the best cooling efficiency on LIBs being about to undergo TR•Novec 1230 existed in the enclosed space stably and protected LIBs from forming firesChemistry; Electrochemistry; Electrochemical energy storage