R. Spray, S. Lele
Exponent,
United States
Keywords: energy storage, batteries, battery, BESS, lithium-ion, safety, reliability
Summary:
Energy storage systems are key to a clean, reliable and efficient power grid. The number of ESS installations has drastically increased across the world with a focus on rechargeable batteries such as Lithium-ion (Li-ion) batteries. The success of these batteries in other small-scale applications has prompted a significant increase in the deployment of such batteries in grid energy storage systems. This has also brought to the forefront the significance of safety when dealing with chemistries such as Li-ion. The battery systems vary depending on size, capacity, and chemistry and understanding the failure modes associated with these systems and addressing them has become of utmost importance to ensure the safety and reliability of battery energy storage systems (BESSs). These failure modes and hazards associated with BESSs can be attributed to various factors such as cell-level manufacturing defects, inappropriately rated electrical components, environmental conditions and other system-level weaknesses. It is critical to understand the risks associated with BESSs when designing the system not only to prevent high-cost damages but to ensure the safety of the surrounding infrastructure and environment, as well as personnel involved and reduce downtimes due to spontaneous failures. This presentation provides an overview of a typical BESS, and includes a discussion related to the failure modes associated with BESSs and an approach to perform a safety and risk analysis of these systems during the design stage. This will include strategies such as Failure Modes and Effects Analysis (FMEA) for appropriately identifying and mitigation risks that can come from a variety of components, as well as integration of them. We also discuss the typical safety requirements and emergency protocols that the battery system should comply with along with a case study highlighting the importance of performing a hazard analysis. While there are many different technologies utilized in BESSs, this presentation focuses on the Li-ion type of BESS.