Introduction
As we move toward a future powered by renewable energy, the role of lithium-ion batteries in battery energy storage systems (BESS) has never been more critical.
However, alongside their benefits, these batteries come with risks—chief among them is thermal runaway. At EticaAG, we’ve developed an advanced immersion cooling technology that redefines safety in battery storage systems.
Let me take you through the challenges, the innovation behind our solution, and why immersion cooling is setting a new industry standard.
The Problem: Thermal Runaway in BESS
Lithium-ion batteries generate heat during operation. Normally, this isn’t an issue, but under certain conditions, the heat can escalate into something called thermal runaway.
Thermal runaway is a chain reaction where heat inside a battery cell triggers chemical reactions, which then releases more heat. This can lead to fires or even explosions.
What causes thermal runaway? Here are 3 main reasons:
- Overcharging or excessive heat from external sources.
- Damage to the battery casing or internal components.
- Manufacturing defects or poor design.
When thermal runaway occurs, the consequences are serious: fire, system failure, and significant safety risks. Traditional cooling methods often fall short of fully preventing these outcomes, which is why we need a better solution.
The Innovation: How Immersion Cooling Solves BESS Fire Risk
Our immersion cooling technology takes a radically different approach to battery thermal management. Instead of relying on air or indirect cooling, our system submerges battery cells in a specialized, non-toxic, and non-conductive liquid.
Battery Cells Submerged in Liquid Coolant
The foundation of immersion cooling lies in submerging each battery cell in a non-toxic, non-corrosive, and non-conductive (dielectric) liquid coolant. This coolant has two critical properties: it efficiently absorbs heat and prevents electrical conduction. By directly contacting the battery cells, the fluid eliminates hotspots and ensures even heat distribution.
Unlike air or water-based cooling systems, this method doesn’t rely on external plates or indirect heat transfer. The liquid coolant wraps around every surface of the battery cell, creating an environment where excess heat is swiftly and safely removed.
This design also plays a key role in fire suppression. When a battery cell experiences a thermal event, the liquid coolant dissipates the heat and extinguishes any flame before it can spread to adjacent cells. This effectively halts the progression of thermal runaway.
Patented Cooling Circulation System
Immersion cooling at EticaAG goes beyond simple submersion. Our patented cooling circulation system ensures consistent, dynamic temperature regulation across the entire system.
Here’s how it works:
- The coolant absorbs heat directly from the battery cells and flows to a reservoir where the heat is dissipated.
- The system employs pumps to circulate the liquid, preventing thermal gradients that can compromise performance.
- Our integrated battery management system works in real time to circulate the coolant throughout the system as needed (more on this below).
In addition to maintaining stability during regular operation, this circulation system provides redundancy during peak thermal events. Even if one part of the system experiences strain, the circulation ensures that heat is swiftly transported away from critical areas, safeguarding the battery’s integrity.
Battery Management System (BMS)
The integration of a Battery Management System (BMS) takes immersion cooling to the next level. This intelligent monitoring system works in real time to detect and respond to changes in battery temperature.
When the BMS identifies a cell or module that is heating beyond normal operating conditions, it triggers the cooling system to adapt. Pumps can increase circulation rates, accelerating the movement of coolant to transfer heat away from the affected area more quickly.
Conversely, during periods of low thermal activity, the system can operate at reduced capacity, optimizing energy use and extending the life of the cooling equipment.
The BMS also plays a preventive role. By providing detailed data on cell performance, it helps identify early warning signs of potential failures, allowing for proactive maintenance.
This ensures that the battery pack operates at peak efficiency while reducing the risk of unexpected thermal events.
How Immersion Cooling Compares to Traditional Fire Suppression Methods
Not all fire suppression methods are created equal. Here’s how immersion cooling stacks up against traditional methods.
Water-Based
Water-based cooling is one of the most common methods for managing heat in lithium-ion batteries. It uses water or water-glycol mixtures to transfer heat away from the cells via cooling plates or pipes. This approach is effective for large systems, such as utility-scale energy storage or electric vehicles, where significant heat dissipation is required.
However, water-based cooling has critical limitations. The biggest concern is the conductivity of water. Even with additives to reduce electrical conductivity, there is always a risk of short circuits if the water comes into contact with the battery cells.
Corrosion of system components over time is another challenge, particularly in systems exposed to fluctuating thermal conditions.
Additionally, in cases of thermal runaway, water-based systems may fail to suppress fires effectively, as they do not address the root cause of excessive heat within a single cell.
Gaseous-Clean Agents
Gaseous clean agents, such as FM200 or Novec 1230, are commonly used in fire suppression systems for energy storage. These gases are stored under pressure and released into the battery enclosure during a fire event. The primary mechanism of these agents is either cooling the surrounding air or displacing oxygen to suppress flames.
However, gaseous clean agents have notable limitations when it comes to lithium-ion batteries.
While they can suppress visible flames, they do not address the ongoing heat generated by thermal runaway. This means that the internal chemical reactions within the battery cells can continue, potentially reigniting the fire.
Furthermore, the effectiveness of these agents depends on maintaining a sealed environment to ensure adequate concentration, which can be challenging in large or open systems.
Aerosol Agents
Aerosol-based fire suppression systems work by releasing fine particles into the air that disrupt the chemical chain reaction of combustion. These systems are often used in enclosed spaces where rapid deployment is needed to contain fires.
However, like gaseous agents, aerosols are ineffective at addressing the heat buildup that drives thermal runaway.
They also require a tightly sealed environment to maintain their concentration, which limits their use in larger or ventilated spaces.
Additionally, aerosols do not offer cooling capabilities, meaning they cannot prevent the escalation of thermal events once they begin.
Immersion Cooling
Immersion cooling stands apart by addressing the root cause of thermal runaway, excessive heat at the battery cell level.
Instead of attempting to suppress flames after they start, immersion cooling prevents fires altogether by submerging battery cells in a dielectric fluid. This fluid absorbs and disperses heat directly from the cells, preventing hotspots and eliminating the conditions that lead to fire propagation.
Unlike water-based systems, immersion cooling is non-conductive, so there’s no risk of electrical shorts. It also provides continuous cooling, even in the event of a pump or power failure, ensuring system stability.
Compared to gaseous and aerosol agents, immersion cooling offers both active heat management and passive fire suppression, making it the most comprehensive solution available for energy storage systems.
The Benefits of Immersion Cooling
Suppresses Fire and Prevents Propagation
One of the most significant advantages of immersion cooling is its ability to stop thermal runaway in its tracks. By submerging battery cells in a non-conductive liquid coolant, the system prevents excessive heat from spreading to adjacent cells. This eliminates the chain reaction that can lead to catastrophic fires or explosions.
In tests, immersion cooling has proven to effectively suppress thermal events before they escalate, offering a level of safety unmatched by traditional cooling methods. The result is not just a safer energy storage system but also peace of mind for operators and end-users.
Improved System Efficiency and Longevity
Stable temperatures are crucial for battery performance and lifespan. With immersion cooling, the direct transfer of heat ensures that all cells operate within an optimal temperature range, reducing wear and tear caused by thermal stress.
By maintaining consistent conditions, the system minimizes the risk of performance degradation over time. This means fewer replacements, lower maintenance costs, and a longer useful life for the battery pack. The technology also enhances energy efficiency, as cooler batteries can operate more effectively without overheating.
Scalability and Versatility for Various Applications
Immersion cooling isn’t a one-size-fits-all solution—it’s adaptable to a wide range of industries and system sizes. Whether you’re managing energy storage for a data center, utility-scale renewable energy, or electric vehicle charging stations, the technology can be scaled to meet your needs.
Its versatility extends to other sectors like telecommunications, transportation, and healthcare, where reliable and safe energy storage is critical. No matter the application, immersion cooling provides the same benefits: enhanced safety, improved performance, and long-term reliability.
A Safer Future for Energy Storage
At EticaAG, we’re redefining what safety means for battery energy storage. Immersion cooling is more than an innovation; it’s a solution that addresses one of the industry’s most pressing challenges.
If you want to explore how this technology can revolutionize your energy storage projects, download our white paper for a deeper dive.
Ready to take the next step? Contact us to discuss your specific needs and discover how EticaAG can help you build a safer, more reliable future.
