ESS Gas Detection Based on Large Scale Fire Testing
Thursday, October 8, 2020
2:25 PM – 2:35 PM EDT
Objective: Projections for new installations of energy storage systems continue to grow. This growth can be seen in energy storage targets established by an increasing number of states. However, concerns over the safety of these systems are evidenced by ongoing work on NFPA 855, the work to evaluation system to the UL9540A test method, and a growing number of battery fires in South Korea and the US. Monitoring and controls play a vital role in the safety of these systems. During this presentation, Li-ion Tamer will report the location and type of gas detection within a lithium-ion ESS based upon gas analyses conducted during large-scale fire testing using methods specified in UL9540A.
Methods: Gas generation and accumulation during ESS failures has been a topic of concern among the first responder and the ESS industry following the ESS fire and subsequent explosion at the APS site in Surprise, Arizona in April of this year. The topic of explosion was also one of the five topic areas addressed during a recent series of webinars hosted by CUNY regarding the development of a data utilization guide for UL 9540A large-scale fire testing to support permitting decisions efforts by Department of Building and the FDNY. A data-based approach is outlined in UL 9540A testing for the calculation of explosive atmospheres caused by off-gassing of lithium ion batteries. Further, IEC 62933-5-2 prepared by TC120, and recently adopted as the Korean Standard following their five-month fire committee investigation, outlines the use of off-gassing data collected during large scale fire testing to inform design decisions for the location and type of gas detection equipment. Nexceris has conducted a large number of tests to determine the off-gassing characteristics of lithium ion batteries including testing to UL 9540A test methods. This tests and methods will be shared as part of the technical presentation.
Conclusions: Li-ion Tamer will share a case study of how off-gas data collected during recent large-scale fire testing is being applied to improve the protection measures utilized in BESS installations. It will be demonstrated how this data-based approach improves the situational awareness as failures develop in energy storage systems by providing the ability to diagnose when faults begin prior to thermal runaway occurring in a single cell. As the failure develops, the gas environment evolves and the associated hazards change. A properly designed gas detection system can help to diagnose each stage of failure providing opportunities to improve the operational safety of the ESS and the safety of first responders at the scene.