Understanding the Risk, Causes and Prevention Measures

Lithium-ion batteries are a go to power source for energy storage systems due to their high energy density. They power many applications such as, cell phones, laptops, electric vehicles, solar systems, and data centres. However, as their use continues expands across many industries, the risk of lithium-ion battery fires also increases.

Lithium having a high electrochemical potential along with lithium-ion’s efficient storage in electrode material contribute to lithium-ion batteries having a high energy density. This enables the batteries to be able to store a large amount of energy proportional to their size and weight. Although this is a major advantage of these batteries, it is because of this high energy density that they are susceptible to fire and explosion.

Causes of Lithium-Ion Battery Fires

Lithium-ion batteries can experience a chain of exothermic reactions resulting in the decomposition of electrolytes and flammable organic solvents such as ethylene carbonate (EC), dimethyl carbonate, vinylene carbonate, and diethyl carbonate. This decomposition occurs due overheating because of overcharging, internal short circuit due to defects or damage or external damage that compromises the batteries internal structure.

When the battery ignites or explodes it is because of a process called thermal runaway, this is when the battery experiences an uncontrollable rise in temperature leading to dendrites- needle-like lithium structures which grow long and puncture the separator causing a short circuit, leading to rapid heating and realise of flammable gases like hydrogen, methane, and carbon monoxide.

Lithium-ion batteries entering Thermal Runaway

Battery fires are very difficult to extinguish, once they enter thermal runaway it can take a couple of minutes for a fire or explosion to occur. This depends on the rate of thermal escalation, where temperatures can reach or even exceed 600°C. The gases produced during thermal runaway are not only toxic but also contribute to fuelling the flames. The affect also acts as a catalyst for an explosion. The likelihood of a thermal runaway taking place increases as the number battery cells within a perimeter increases.

Preventing Lithium-Ion Battery Fires with Early Warning Detection

When it comes to lithium-ion battery safety, prevention is better than cure. Once a lithium battery fire ignites, it becomes difficult to extinguish due to the high temperatures, rapid energy release, and self-sustaining thermal runaway. Traditional fire extinguishers are largely ineffective against these fires and the best way to alleviate these risks is by using early warning detection systems that can identify temperature spikes, gas emissions, and overheating before a thermal runaway event occurs.

Alien Systems and Technology’s Cloud Chamber Detector (CCD) is a highly sensitive early warning smoke detection system designed for very early warning fire detection. It can detect particles released by overheating lithium batteries and off-gassing, providing a critical early warning before visible smoke or fire occurs.

Similarly, the Cirrus Hybrid Aspirating fire and smoke detector which utilises both Cloud Chamber Detection (CCD) and Early Warning Smoke Detection (EWSD), can identify fires with minimal visible smoke which is common in lithium-ion battery failures. By using complex algorithms, the Cirrus Hybrid detect true fire conditions but also helps to reduce false alarms. This makes it an ideal solution for detecting fires in battery storage facilities, data centres, energy storage systems, and other high-risk environments where lithium-ion battery fire risks are high.