Energy Storage Systems Safety Lessons Learned

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Take-aways from Recent ESS Fires
Prevention
▪ Maintaining strict operational limits via robust Battery Management Systems (BMS) can inhibit thermal runaway
▪ Thermal runaway may be inevitable at a cell level due to cell defects, aging
▪ Propagation depends on many factors, such as chemistry, cell packaging, thermal resistance of the module
▪ Monitoring of voltage, current, temperature, and gases may provide failure pre-conditions
Mitigation
▪ Clean agent fire suppression (alone) is often incapable of stopping propagating thermal runaway
▪ Cascading thermal runaway generates large amounts of heat –water suppression requires large volumes
▪ Explosive off-gases can build quickly – ventilation is essential to avoid deflagration
▪ Coordination, planning, and communications before, during, and post event can save lives and equipment
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