Utility-scale battery fire risk: prioritising safety & security

Just as momentum and confidence in Australia builds for batteries to be installed in households, businesses, or their neighbourhoods, the Tesla Megapack battery fire in Geelong, Victoria wakes us up to the fact that these types of installations are not risk-free.

This utility-scale battery fire is the first visible and high-profile incident that Australia has seen. While an official investigation is still underway on the cause of the fire, this highlights how important transparency is, and the findings from this incident will inform the industry going forward.

Battery fires are infrequent incidents in any stationary installation. The cause can be many different combinations of scenarios, and this can happen anywhere in the world. However, according to media reports, the root cause of the Geelong battery fire was most likely to be a ‘thermal runaway’ incident where a heated cell transfers its heat to an adjacent cell.

Dr Bruce Godfrey, Energy Renaissance Chairman said, “Customers expect their batteries to be safe, and this should be an inherent part of the design in any energy storage solution. Thermal runaway incidents are rare, but this needs to be investigated thoroughly, so regulators, government agencies and first responders are equipped with the insights to respond to future incidents appropriately.”

The findings on thermal runaway incidents that are publicly available show a level of consistency on the impacts of a cell level failure on utility-scale battery installations. For example, key findings from a report released for an incident at the APS McMicken Battery Energy Storage Facility in Arizona, the United States, that occurred in 2019 have shown:

  • An internal failure in a battery cell was responsible for initiating a thermal runaway incident.
  • The fire suppression system was incapable of stopping thermal runaway.
  • The lack of thermal barriers between cells had led to the cascading thermal runaway.
  • That flammable gases concentrated without a means to ventilate had contributed to the fire.
  • The emergency response plan did not have an extinguishing, ventilation, and entry procedure that could have been addressed during the battery installation process.

As a battery manufacturer, Energy Renaissance has investigated thermal runaway incidents that have been reported. That is why we’ve put safety at the forefront of our product design and manufacturing since inception.

Energy Renaissance has designed batteries that are safe, cybersecure and affordable. Our initial cell chemistry of choice is lithium iron phosphate, one of the safest and most stable lithium-ion battery chemistries currently available. However, our superStorage™ family of batteries will remain cell chemistry agnostic as we make improvements and adopt advancements in battery safety and new cell technologies. Doing so will allow us to evolve our platform with safety as a priority in our design and development.

Our work with CSIRO with the Innovative Manufacturing CRC (IMCRC) and the Advanced Manufacturing Growth Centre (AMGC) supports the safety and security in our superStorage family of batteries.

In an interview with EcoGeneration, Dr Adam Best, Principal Research Scientist at CSIRO and research collaborator at Energy Renaissance describes “Charging in a battery has to be done really carefully,” Best says, “and a BMS is designed to control voltage and current in a cell to exactly stop this from happening”.

Dr Best said, “A Battery Management System monitors the performance of a battery in real-time, collecting data such as temperature, pressure, voltage and current. This data can be used to calculate the state of charge or impedance of cells. With a BMS, we have set boundaries around the currents and voltages, so that battery cells are always operating within a safe and secure pre-determined range.”

Energy Renaissance batteries are Australian made, designed to perform in hot climates and reinforced with cooling systems in heat-stressed environments. In addition, the Battery Management System (BMS) that we’ve designed provides us with a world-class defence-grade cybersecure BMS that delivers real-time data, analytics and remote management capabilities that will drive down the risk of battery failure for utility-scale energy storage projects.

Dr Godfrey said, “A Battery Management System monitors the performance of a battery in real-time, collecting data such as temperature, pressure, voltage and current. This data can be used to calculate the state of charge or impedance of cells. With a BMS, we have set boundaries around the currents and voltages, so that battery cells are always operating within a safe and secure pre-determined range.”

“Energy Renaissance will determine how we can better predict the probability of a thermal runaway event. This will enhance the safety features in the BMS so it can detect issues before a failure might occur.”

Together with our partners, clients and the broader industry, we will reinforce confidence in all battery projects, and we look forward to a future of – clean, stored energy everywhere.