Fire Protection Materials Preventing Thermal Runaway in Lithium-Ion Batteries
The Growing Need for Fire Protection in Lithium-Ion Batteries
Thermal runaway and system safety are critical challenges when using lithium-ion batteries in battery energy storage systems (BESS). Recent incidents, such as a suspected battery explosion in South Korea’s national data center that disrupted major online services, highlight the urgency of minimizing the risks of thermal runaway events.
According to IDTechEx’s upcoming report “Thermal Management, Fire and Explosion Protection for BESS 2026–2036,” multiple approaches such as thermal management, active cooling, and robust battery management systems are key. However, none of these methods alone can fully eliminate risk making fire protection materials an essential passive safeguard against thermal runaway propagation.
Understanding Thermal Runaway and Its Causes
Thermal runaway occurs when a battery cell overheats uncontrollably, triggering a chain reaction that can lead to fire or explosion. Common causes include:
- Overcharging or overheating of cells
- Internal short circuits due to manufacturing defects
- Mechanical damage or external impact
Higher energy density cells, which are increasingly used for efficiency, often produce more heat during thermal runaway. As electric vehicles (EVs) and energy storage systems expand globally, ensuring battery fire safety becomes increasingly vital.
Despite EVs statistically having fewer fires than combustion vehicles, the potential severity of thermal runaway events means fire protection must never be overlooked.
The Role of Fire Protection Materials
Fire protection materials provide a passive layer of safety, designed to prevent or slow down the spread of heat and flames within a battery pack. They can be applied at two main levels:
1. Cell-Level Protection
At this stage, materials are placed directly between or around individual cells to prevent propagation between them. Common cell-level materials include:
- Encapsulating foams
- Aerogels
- Compression pads with additives
- Mica sheets
These materials work to contain potential failures at the source, preventing heat from spreading to adjacent cells.
2. Pack-Level Protection
At the pack level, materials provide barriers between modules or around the entire battery pack. They are designed to prevent fire from escaping or spreading beyond the pack enclosure. Typical materials include:
- Ceramic blankets and non-wovens
- Powder and intumescent coatings
- Aerogels
- Mica composites
These materials are chosen for their thermal resistance, density, and cost efficiency, helping manufacturers balance performance with safety and affordability.
Choosing the Right Fire Protection Material
Selecting the right fire protection solution requires balancing multiple properties:
- Thermal conductivity (to resist heat transfer)
- Density and thickness (for lightweight applications)
- Dielectric strength (for electrical insulation)
- Maximum fire protection temperature
- Cost and scalability
A material may be lightweight, but if a large amount is required for full protection, it might not be efficient. Similarly, combining multiple materials could increase cost and complexity.
According to IDTechEx, the market for fire protection materials is rapidly expanding, with over 150 materials from 72 suppliers currently analyzed in their material database. Each offers different strengths depending on the application and performance requirements.
In the EV market, IDTechEx forecasts that demand for fire protection materials will grow at a CAGR of 15% through 2035, reflecting global investment in safer, more resilient battery systems.
As energy storage systems and electric mobility continue to scale, fire protection materials for lithium-ion batteries will play a pivotal role in enhancing safety, reliability, and public confidence. Whether at the cell or pack level, these materials form the last line of defense against thermal runaway and its catastrophic effects.
For more information on this report, visit IDTechEx.com/FPM.
