Laboratory for fire assessment of Li-Ion batteries

TECNALIA has a test platform in its safety and fire protection laboratory to assess the propagation of thermal runaway events between cells in Li-Ion, in modules and battery packs. By means of controlled tests, extreme conditions (overheating, overload, short circuit, mechanical damage) are induced to analyse:

• Thermal runaway propagation between cells/modules
• The behaviour of the battery enclosure in these conditions
• The effectiveness of barrier materials and products in mitigating risks
• Passive fire safety in energy storage systems
• The correct functioning of solutions to reduce the evacuation and channelling of toxic gases and fumes
• Assessment of the internal pressure control systems in the battery during the thermal runaway event

Tests are performed using standardised methodologies (IEC, UL, RTCA) and adapted to specific customer needs, including real-time monitoring of gases, temperatures and pressures.

The problem we address is the assessment of the fire safety level of energy storage systems against critical situations, such as those that can arise in Li-Ion batteries. In such technologies, a fault in one cell can cause fire to spread to other cells or modules. To ensure fire safety, storage solutions must be tested in extreme conditions, such as overheating, overloading, short-circuiting or mechanical damage, which replicate real failure scenarios.

Current international standards (IEC, UL, RTCA) require rigorous and accurate tests that many companies are not able to carry out without access to specialised infrastructure. This gap poses a challenge to the validation both of the passive fire safety of systems and their compliance with global standards, especially in critical sectors such as electric vehicles, aeronautical transport and stationary energy storage.

Our lab focuses on addressing this issue by providing advanced methods and tools to identify, analyse and mitigate risks, thus ensuring the protection of users, equipment and the environments in which these systems operate.

Our laboratory solves these problems using a comprehensive approach that combines advanced experimental methods and regulatory compliance.

To induce thermal runaway, we apply extreme conditions such as thermal, mechanical, overcharge and short-circuit abuse, replicating real-life failure scenarios on Li-Ion cells, modules and battery packs. During these tests, we assess the heat and flame propagation between cells and modules, analysing the behaviour of the battery enclosure under critical conditions.

At the same time, we validate the effectiveness of barrier materials and products using methodologies such as Torch & Grit, ensuring that these elements mitigate the propagation of thermal runaway. The entire process is complemented by advanced real-time monitoring, recording key parameters such as gases, temperatures and pressures for accurate and reproducible data.

In addition, our tests are aligned with recognised international standards (IEC 62619, UL 9540A, RTCA DO-311, among others), ensuring regulatory compliance. Finally, we develop customised methodologies that adapt to the specific needs of R&D projects or to the technical requirements of each client, offering flexible solutions oriented towards safe innovation in energy storage systems.

• Safety guarantee: We validate storage systems if they withstand extreme conditions.
• Regulatory compliance: We facilitate the classification of products according to global standards.
• Risk reduction: We minimise the probability of fire in critical applications (electric vehicles, aeronautics, etc.).
• Safe innovation: It allows new materials or designs to be tested in real conditions.

• Certified infrastructure: ENAC ISO 17025 accredited laboratory for electrical and thermal testing
• Technical expertise: Specialised battery safety and energy storage equipment.
• Large-scale capability: Tests with complete battery systems (modules and packs).
• Remote monitoring: Advanced technology to record data in real time.

The assessment of the consequences of thermal runaway helps you to improve the safety levels of your battery.

This service is aimed at companies and institutions in the following sectors:

1. Battery and energy storage system manufacturers
   • Companies producing cells, modules and batteries for critical applications
2. Automotive and transport OEMs
   • Manufacturers of electric vehicles, micro-mobility and rail/aeronautical transport
3. Electrical and electronic systems integrators
   • Companies implementing energy storage solutions in infrastructure or devices
4. Manufacturers of battery enclosures and materials and products for their internal protection
5. Technology centres and R&D laboratories
   • Institutions that validate designs or materials in extreme conditions
6. Certifying and insurance bodies
   • Agencies requiring technical data for regulatory compliance or risk assessment