Fire & Explosion Hazards for BESS
Explosion Risk in BESS : THERMAL RUNAWAY
A thermal runaway is a phenomenon of chain reactions that is often uncontrollable, and which can lead to the explosion of the BESS.
It produces an exothermic reaction, which generates a strong production of heat (up to 1000°C in certain cases) and releases a high production of flammable gases such as hydrogen, as well as those of toxic fumes.
The power of a thermal runaway depends on the battery chemistry used, and its SOC (state of charge).
During thermal runaway, heat from the faulty cell can cause adjacent cells to fail and trigger the chain reaction that will spread throughout the battery and can quickly destroy the entire battery energy storage system along with nearby equipment.
THE CAUSES OF TRIGGERING OF THIS EVENT
CAN BE MULTIPLE:
Manufacturing defect of the cell, mechanical abuse such as crash or penetration, electrical abuse such as overloading or short circuit of the cell, thermal abuse related to the excessive temperature of the thermal runaway.
The severity of the risks associated to thermal runaway show the importance of implementing measures to mitigate the risks of explosion and fire, such as the use of explosion-proof panels.
Detecting and releasing flammable gases are two measures discussed in NFPA 855 2023.
