Inhibition effect of liquid nitrogen on thermal runaway propagation of lithium ion batteries in confined space

In practical usage, lithium ion batteries (LIBs) pack is placed in a confined space. Due to the insufficient heat dissipation, the thermal runaway (TR) and propagation is more likely to occur. Thus, developing highly-efficient suppression agent for TR and its propagation in confined space is of great significance. In this paper, the suppression effect of liquid nitrogen (LN2) on TR and its propagation of LIBs is investigated. TR suppression effectiveness of LN2 under different injection amount, injection position, state of charge (SOC) and heating power are investigated. As observed, the heat of battery in confined space is difficult to dissipate. With the increment of battery spacing, the difficulty for TR of second battery is elevated. The cooling effect on battery is promoted with the incremental usage of LN2. Also, LN2 injected from the top of device shows better cooling effect than that injected from side of device. Overall, LN2 holds significant inhibitory effect on TR and its propagation of LIBs, extinguishing the flame quickly and reducing the surface temperature to a safe value in a short time. •Thermal runaway (TR) behaviors of battery in open and confined spaces are studied.•Liquid nitrogen (LN2) inhibition effect on battery TR in confined space is studied.•LN2 suppression effect on TR propagation of battery is investigated in detail.