Hithium completes the World's First All Open-Door Large-Scale Fire Test

Sets new safety benchmark under four ultimate test challenges

XIAMEN, China, June 5, 2025 /PRNewswire/ — Hithium, a leading global energy storage technology company, has completed the world’s first all open-door large-scale fire test of its ∞Block 5MWh battery energy storage system (BESS). This pioneering achievement sets a new benchmark for safety validation methods, marking a milestone in the global energy storage industry.

As thermal runaway and other safety incidents in BESS draw increasing concern, more rigorous and standardized safety testing is urgently needed. The open-door fire test was developed to meet this requirement—featuring four ultimate test challenges:

All open-door combustion: The container doors remained fully open throughout the test, creating an unrestrained combustion environment with intensified oxygen flow—far more severe than traditional closed-door scenarios
15cm minimum spacing: The BESS were placed side by side and back to back with just 15cm spacing. Despite flames over 1300°C, no thermal propagation occurred, proving effective close-range isolation.
Fire suppression system deactivated: All fire suppression systems were deactivated. The system relied solely on passive fire protection to withstand prolonged intense fire, demonstrating autonomous fire resistance and reliability.
100% State of Charge (SOC): The BESS was tested at full capacity to maximize thermal energy release, validating the system’s reliability and stability under the harshest conditions.

Conducted by UL Solutions, a globally recognized safety certification authority, and witnessed by certified U.S. fire protection engineers and customers, the test strictly adhered to UL 9540A and NFPA 855 safety standards.

Despite undergoing 15 hours of full combustion, the system structure remained intact, with no fire propagation to any of the three adjacent containers. This result validates Hithium’s multi-layered passive safety architecture and thermal isolation capabilities, even under the most extreme conditions.

This achievement highlights Hithium’s commitment to innovation and quality, providing valuable insights for future safety standards in the industry. Moving forward, Hithium will continue to advance safety performance through technology and global collaboration, driving the industry toward a safer and more reliable future.

About Hithium

Founded in 2019, Hithium is a leading global company in new energy technology, committed to delivering energy storage solutions centered on advanced energy storage battery and system technologies. Hithium has cultivated robust research, production, sales, and service capabilities in global markets.

As the only single-focused energy storage company to achieve GWh-scale global shipments of lithium-ion ESS batteries, HiTHIUM’s customer-centric focus drives technological and innovative products and solutions for customers across more than 20 countries and regions.