With the significant push towards renewable energy, such as wind and solar, the demand for battery energy storage systems (BESS) has grown exponentially.
Most BESS utilise lithium-ion (Li-ion) batteries, bringing particular fire risks. There are many stories of laptop and cell phone lithium-ion batteries catching fire, and on a larger scale, there were 23 BESS fires in South Korea alone between 2017 and 2019, resulting in losses valued at $32 million.
As a result, there is a rapidly evolving regulatory environment to address these risks. One of the leading regulatory authorities in the USA, Underwriter Laboratory (UL), developed UL 9540A to address ‘Thermal Runaway Fire Propagation in Battery Energy Storage Systems’. Already there have been four iterations of the standard since 2014.
Most authorities will agree that there are two main windows of opportunity to implement fire protection measures for BESS. The first and most critical is the detection of off gas (battery electrolyte vapours), which typically occurs 11-12 minutes before smoke is generated. Li-ion Tamer GEN 3 from Xtralis is designed to monitor Lithium-ion batteries of all chemistries and to detect any off-gases to provide an early warning to BESS system providers. When the Li-ion Tamer GEN 3 alerts to the presence of an off gas, it can activate several mitigating actions. Perhaps the most important is shutting down power to the affected cell(s). Additionally, the gas detection equipment can:
• Activate a ventilation system within the BESS enclosure to remove flammable gases and heat.
• Activate local and remote alarms.
• Provide an early warning for operators to take additional measures.
If preventative measures are unsuccessful and a damaged lithium-ion battery ignites, fire suppression measures must be implemented to contain the resulting fire and minimise the potential for propagation to other battery cells within the BESS.
Stat-X condensed aerosol fire suppression is the fire suppression system of choice of several lithium-ion battery OEMs and leading global BESS integrators, having undergone rigorous private and commercial testing in line with UL and NFPA standards. The tests concluded that the Stat-X agent successfully extinguished single and double-cell battery fires and prevented a re-flash of the fire due to its residual nature.
It is also important to note that condensed aerosol fire suppression agents have no global warming or ozone depletion properties. They do not harm sensitive equipment and require limited clean up after discharge. The agents are rated for normally occupied areas.
Technoswitch believes the combination of Li-ion Tamer and Stat-X offers an ideal detection and containment solution for BESS fires.
