Energy Storage Safety Project Background

Since the publication of the first Energy Storage Safety Strategic Plan in 2014, there have been introductions of new technologies, new use cases, and new codes, standards, regulations, and testing methods. Additionally, failures in deployed energy storage systems (ESS) have led to new emergency response best practices.

In general, energy that is stored has the potential for release in an uncontrolled manner, potentially endangering equipment, the environment, or people. All energy storage systems have hazards. Some hazards are easily mitigated to reduce risk, and others require more dedicated planning and execution to maintain safety.

Interest in storage safety considerations is substantially increasing, yet newer system designs can be quite different than prior versions in terms of risk mitigation. An uncontrolled release of energy is an inevitable and dangerous possibility with storing energy in any form.

Resulting primary hazards may include fire, chemical, crush, electrical, and thermal. Secondary hazards may include health and environmental. EPRI's energy storage safety research is focused in three areas, or future states, defined in the Energy Storage Roadmap: Vision for 2025.

Energy storage safety gaps identified in 2014 and 2023. Several gap areas were identified for validated safety and reliability, with an emphasis on Li-ion system design and operation but a recognition that significant research is needed to identify the risks of emerging technologies.

This work describes an improved risk assessment approach for analyzing safety designs in the battery energy storage system incorporated in large-scale solar to improve accident prevention and mitigation, via incorporating probabilistic event tree and systems theoretic analysis. The causal factors and mitigation measures are presented.