Experimental investigation on the cooling and suppression effects of liquid nitrogen on the thermal runaway of lithium ion battery

Abstract

The thermal runaway (TR) of lithium ion batteries (LIBs) becomes a potential risk of inducing serious fire accidents, threatening people's lives and property. Therefore, it is urgent to determine an effective method to prevent or mitigate this hazardous process. This work experimentally studies the suppression, delaying and cooling effects of liquid nitrogen (LN) on TR of LIBs. Besides, the cooling mechanism and cooling capacity of LN on high-temperature LIBs are analyzed and calculated quantitatively. The results show that TR is prevented by applying LN before the surface temperature (Tw) is reached the critical TR suppression temperature. The delaying effect of LN on TR is weakened with increasing the surface temperature of the battery. Only 29.3 g of LN sprayed on the battery reduces the temperature of 9.24 Wh LIB from about 700 °C to less than 100 °C within 80 s. While the cooling effect of LN to the inside the battery becomes more superior as the application time prolongs. Furthermore, the calculated average cooling rate decreases from 10.3 °C/s to 2.84 °C/s when Tw reduces from 800 °C to 0 °C, illustrating that the cooling effect of LN is weakened with decreasing Tw.