Could New Battery Energy Storage Safety Technology Have Prevented the Moss Landing Fire?

February 21, 2025

Curated By Clarion Energy Content Directors

Contributed by Matt Ward, President, EticaAG

The global shift towards renewable energy has resulted in an unprecedented demand for battery energy storage systems (BESS). These systems play a crucial role in integrating renewable energy sources into the grid, ensuring both reliability and stability. However, safety concerns, particularly the risk of fires due to thermal runaway, present significant challenges. Notable incidents, such as the fire at the Moss Landing Energy Storage Facility, have highlighted the limitations of current cooling and safety measures.

Immersion cooling, patented for BESS by EticaAG—a partnership between Etica Battery and AGI—provides optimal thermal management and advanced fire suppression. This technology directly addresses the root causes of thermal runaway, enhancing safety, reliability, and performance compared to conventional methods. This article explores the technical aspects of immersion cooling and its effectiveness in mitigating risks for BESS installations.

Understanding Thermal Runaway

Thermal runaway occurs when a battery cell generates heat faster than it can dissipate, leading to a chain reaction of overheating and failure in adjacent cells. This phenomenon is typically triggered by external stressors such as physical damage, overcharging, or elevated temperatures, which accelerate internal chemical reactions within the battery uncontrollably. As these reactions progress, they produce heat, increasing chemical activity and creating a self-sustaining feedback loop that can result in fire or explosion. This process poses a significant safety hazard and undermines the reliability and operational efficiency of energy storage systems.

Limitations of Current Cooling and Fire Suppression Methods

Air cooling relies on circulating air to dissipate heat, but it is often ineffective in densely packed systems where airflow is obstructed. This can lead to uneven temperature distribution and hotspots that trigger thermal runaway. Liquid cold plate cooling, which uses conduits of liquid to absorb and transport heat away from the cells, offers better thermal management but is inherently reactive, addressing heat only after it has been generated without preventing thermal runaway from occurring. Fire suppression systems are essential but focus solely on responding to fires that have already ignited, rather than preventing them.

These limitations underscore the need for more proactive and comprehensive solutions to manage thermal risks in BESS.

Battery Immersion Technology: A New Approach to BESS Fire Safety

Immersion cooling involves submerging battery cells in a dielectric, non-flammable liquid. However, EticaAG’s patented cooling circulation system goes beyond simple submersion. Here’s how it works:

The coolant absorbs heat directly from the battery cells and flows to a reservoir where the heat is dissipated. Pumps circulate the liquid, preventing thermal gradients that can compromise performance. An integrated battery management system (BMS) circulates the coolant throughout the system in real-time as needed.

Even in the unlikely event of a pump failure, the inherent fire protection remains effective. The non-flammable liquid continuously surrounds the battery cells, preventing fire propagation regardless of circulation. This liquid circulation serves as a direct heat transfer medium, efficiently dissipating heat while isolating cells from oxygen and potential ignition sources. By surrounding each battery cell with this specialized liquid, heat is transferred almost instantaneously, preventing temperature spikes that can lead to thermal runaway. This method also eliminates the need for active air circulation, making it a more efficient and compact solution for thermal management.

Key Benefits of Immersion Cooling: Fire Suppression and Thermal Management

Unlike traditional air or cold plate cooling methods, immersion cooling submerges battery cells directly in a dielectric liquid. This approach ensures uniform temperature distribution across all cells, preventing localized hotspots that could lead to thermal runaway. Immersion cooling mitigates the risk of thermal runaway through two key mechanisms:

1. Oxygen Isolation: The dielectric liquid forms a physical barrier around each cell, preventing exposure to oxygen, which is necessary for combustion. This isolation minimizes the risk of ignition during a cell failure, unlike air-cooled or cold plate systems where venting gases can fuel a fire.

2. Heat Containment and Dissipation: If a battery cell experiences thermal runaway, the surrounding liquid rapidly absorbs and dissipates the excess heat, preventing neighboring cells from reaching critical temperatures. This effectively contains the failure to a single cell, unlike air-cooling or liquid cold plate methods that may not react quickly enough to prevent fire propagation.

In tests, a lithium iron phosphate battery cell was heated to induce a thermal runaway event. The Immersion Cooling system effectively suppressed the resulting flame, preventing fire spread or damage to adjacent cells.

Beyond fire suppression, immersion cooling optimizes battery performance by maintaining a consistent and controlled temperature environment. Lithium-ion batteries degrade faster when exposed to high temperatures or fluctuations. Immersion cooling reduces thermal stress by:

• Minimizing Temperature Swings: The liquid surrounding each cell keeps the battery’s temperature stable, preventing materials from expanding and contracting excessively, which can cause wear and tear over time.

• Reducing Electrolyte Decomposition: High temperatures accelerate the breakdown of electrolytes inside the cells, leading to capacity fading. By maintaining an optimal temperature range, immersion cooling slows degradation and extends battery lifespan.

• Enhancing Energy Efficiency: Batteries operate more efficiently within their ideal thermal window. Stable temperatures improve charge/discharge efficiency and reduce energy losses.

By addressing fire risks and thermal stability, immersion cooling enhances safety and extends the operational life of BESS deployments. This makes it an ideal solution for mission-critical applications such as data centers, grid-scale energy storage, and commercial and industrial backup power, where reliability is paramount.

Could Immersion Cooling Have Prevented the Moss Landing Fire?

The Moss Landing incident, one of the largest BESS fires in recent history, was attributed to thermal runaway triggered by overheating. The failure of cooling systems and fire suppression measures allowed the situation to escalate, causing extensive damage and system downtime. Reports indicated that the conventional air and liquid cooling methods in place were insufficient to dissipate the excessive heat generated by the batteries, leading to cascading failures. The lack of a robust containment mechanism exacerbated the problem as the fire spread quickly across adjacent cells. Additionally, the facility’s fire suppression system struggled to extinguish the flames, highlighting the limitations of reactive measures in addressing thermal runaway events.

Immersion cooling could have fundamentally changed the course of events at Moss Landing by tackling the root causes of the fire. With its ability to provide direct and consistent heat dissipation, immersion cooling would have maintained battery temperatures within safe operating limits, preventing the initial overheating that triggered thermal runaway. By submerging cells in a non-flammable dielectric liquid, any thermal failure would have been immediately contained, preventing heat from spreading to adjacent cells and stopping the cascade of failures before it began. Furthermore, the fire-retardant properties of the immersion cooling liquid would have eliminated any flame from thermal runaway, even in the event of a cell failure. This proactive containment approach would have minimized damage and ensured system stability under high-load conditions.

The Path to Safer Energy Storage

Thermal runaway remains a critical challenge in deploying large-scale battery energy storage systems. Incidents like the Moss Landing fire highlight the limitations of conventional cooling and safety measures. Immersion cooling presents a transformative solution by addressing the root causes of thermal runaway and significantly enhancing fire safety. To ensure the safe and reliable growth of renewable energy storage, the energy industry must embrace innovative technologies like immersion cooling. By prioritizing safety and long-term performance, we can build a more resilient and sustainable energy future.

About the Author

Matt Ward is the new president of EticaAG, on a mission to deliver safe and dependable energy storage solutions for utility, commercial, and residential markets. His career began in the U.S. Navy as a civilian nuclear engineer, where he supervised the maintenance of nuclear reactors on Navy submarines, destroyers, and aircraft carriers. He later transitioned to construction and the oil and gas industry before moving into real estate development. Ward founded Solmicrogrid to provide safe and reliable power to small businesses, with Chick-fil-A as its first client. His career principles emphasize that challenges can often be solved and that perseverance and patience are crucial for success.