Risk Assessment and Safeguarding of Lithium Ion Battery Containing Facilities

The energy portfolio is rapidly moving to renewables and away from traditional fossil-fuel based options. While wind and solar comprise a larger share of energy sources, the technology that allows this energy to be stored and transferred is still either in its infancy or only in development. The most common approach for storage of renewable energy, usually in the form of electricity, is the lithium ion battery. While the technology for lithium ion batteries has been around for decades, only recently has there been large scale ramp up in production of these batteries. Furthermore, the batteries are being collected into large modules, packs, and systems that are capable of powering large vehicles and even entire municipal power grids. Unfortunately, renewable energy is not immune to process safety hazards. After all, batteries store energy as chemical potential, the same as fossil fuels. Exacerbating the problem, the chemicals used in batteries includes hazards the typical motor fuels do not, specifically the potential for self-accelerating decomposition with the generation of highly toxic hydrogen fluoride as a byproduct. To illustrate this fact, a “fire” in a lithium ion battery facility that stored solar power for re-injection into the municipal grid resulted in a violent explosion that sent four first responders to the hospital in Surprise, Arizona, USA, in April 2019. This paper will present the hazards related to runaway reactions that can occur in lithium ion battery containing facilities – going over the anatomy of the runaway reaction in detail. The paper will also present risk analysis techniques and safeguards such as safety instrumented systems, relief systems, and gas detection systems that can be used to reduce risk in these facilities to a tolerable level.