Experimental study on thermal runaway of fully charged and overcharged lithium-ion batteries under adiabatic and side-heating test

•Thermal hazards of fully and slightly charged LIBs are investigated by the EV-ARC and pressure reactor.•The time interval between voltage dropping and TR of 120% SOC is much greater than the other SOCs.•The time interval between voltage dropping and TR is significant for the early warning of TR.•The thermal stability of slightly overcharged LIB is lower than fully charged LIB.•The thermal behavior of LIB under thermal abuse is determined by multi factors.