Experimental investigation on the characteristics of thermal runaway and its propagation of large-format lithium ion batteries under overcharging and overheating conditions

Recent progress in nonflammable electrolytes and cell design for safe Li-ion batteries

“…can be obtained aer overcharging to a specic state of charge (SOC, >100%) or overdischarging to a specic potential (0-2 V). [44][45][46] The typical nail penetration test uses a sharp steel rod forced through a pouch cell at 8 cm s −1 , leading to an internal short circuit with heat generation. For instance, Jia et al 13 applied the nail test and overheating test to detect the safety of 18650 cells with 2.6 M LiFSI in the TMP-based electrolyte, which showed inferior safety than the conventional electrolyte due to the exothermic reactions between the electrolyte (especially the salt LiFSI) and the charged electrodes.…”

Thermal safety and thermal management of batteries

“…These strategies under different conditions are of great significance to promote battery safety for lithium-ion batteries. 13 Except for the leading causes of thermal runaway of lithium-ion batteries (mechanical abuse, 14 electrical abuse, 15 and thermal abuse 16 ), the operation conditions (e.g., low pressure 17 ), types of active materials 18 (e.g., LiFePO 4 (LFP), Li[Ni 1/3 Co 1/3 Mn 1/3 ]O 2 (NCM111), Li[Ni 0.6 Co 0.2 Mn 0.2 ]O 2 (NCM622), and Li[Ni 0.8 Co 0.1 Mn 0.1 ] O 2 (NCM811)), and specifications of batteries (capacity or geometrical structure: 300 Ah LFP for electric buses 19 ) may show different characteristics of thermal runaway. 20 A series of chain reactions will generate considerable heat and produce plenty of byproducts, which will lead to deterioration of the condition and promote the thermal runaway process.…”

A thermal runaway risk warning scheme for power batteries

“…When it exceeds the maximum heat dissipation efficiency of electric vehicles, the working temperature of power batteries will continue to rise, ultimately resulting in the risk of thermal runaway [12] . At the same time, collision, extrusion, overcharging and other factors may also lead to a thermal chain reaction of lithium battery in a very short event [13][14] , further developing into thermal runaway, smoke emission, fire, and even explosion accidents causing injuries or fatalities.…”