World's First Indoor Large-Scale Fire Test Completed: Vision Group's REVO3.0 AIDC LFP Battery Backup Power System Passes All Three UL 9540A-2026 Criteria

Vision Group's REVO3.0 AIDC LFP Battery Backup Power System has successfully completed the world's first indoor Large-Scale Fire Test (LSFT) conducted in strict accordance with the latest UL 9540A-2026, 6th Edition, marking a significant milestone in the safety validation of lithium battery backup power systems for AI data centers.

The test, which subjected the 600kW REVO3.0 system to 74 minutes of full thermal runaway and combustion, demonstrated that thermal runaway remained fully contained within the initiating module with zero propagation to adjacent cabinets. All three core criteria under UL 9540A-2026 were successfully passed, with the entire procedure witnessed by JENSEN HUGHES and UL Solutions, ensuring traceable and verifiable test data.

The test environment was designed to fully reproduce real data center conditions, including walls, ceiling structures and ventilation systems. All three cabinets were fully charged at 100% SOC. The initiating cabinet was positioned at 0 cm from Target Cabinet A and 68 cm from Target Cabinet B, creating an extremely compact deployment scenario while meeting all mandatory UL 9540A-2026 LSFT prerequisites. All active fire suppression and thermal runaway intervention systems were disabled, leaving only the cabinet's passive fire protection. With cabinet doors fully open, the system was exposed to oxygen and subjected to the standard-defined worst-case scenario, followed by open-door flame exposure and 120 minutes of continuous water spray.

Test results confirmed that the initiating Module 7 underwent 74 minutes of full thermal runaway combustion with no explosion. Adjacent Modules 6 and 8 experienced no thermal propagation or thermal runaway and remained fully charged after testing. Target Cabinets A (0 cm) and B (68 cm) remained intact, with no thermal propagation or significant fire damage. System voltage decreased from 640V to 580V while normal voltage output was maintained. Following 120 minutes of water spray and 24 hours of observation, there was no re-ignition, leakage or high-voltage arcing, and all three cabinets remained operational. The initiating cabinet showed visible fire damage but no collapse or significant structural deformation. Against the three core UL 9540A-2026 criteria—fire propagation to adjacent cabinets, building structure temperature rise, and fire barrier integrity—the test achieved a full pass.

Unlike conventional outdoor or unit-level testing, this full-scale indoor test provides direct engineering value for data center deployment. The test advances lithium battery safety validation from cell- and equipment-level verification to system-level validation across modules, cabinets and fire protection systems. For data center design, the 0 cm zero-propagation result provides practical reference data for fire separation, pressure relief and fire protection design. For compliance and approval, the test data supports NFPA 855-related requirements, PE engineering sign-off and on-site compliance approval for the 600kW REVO3.0 system. For the AI era, the test establishes a new practical benchmark for indoor large-scale fire safety validation of data center backup power systems.

A Vision Group representative said: "As data center power density continues to rise, backup power safety must be validated under real deployment conditions. This test was not simply a marketing event—it used real-world test data to address critical engineering challenges. We hope these results can serve as a practical reference for PE engineers, data center owners and design institutes."

The transition from standards-based requirements to full-scale real-world validation marks an important step in the evolution of indoor data center backup power safety. With 74 minutes of extreme combustion, zero fire propagation at 0 cm spacing, and continued system operability after water spray, REVO3.0 demonstrates that system-level safety can withstand worst-case conditions—not simply remain on paper. As AI computing drives higher power density and continuity requirements, backup power has become a critical part of continuous computing operations. System-level safety—from cells and modules to cabinets and fire protection—is the foundation of high-reliability AIDC backup power.

Founded in 1994 and headquartered in Shenzhen, Vision Group (Stock Code: 002733) is a global leading smart energy solutions provider serving critical infrastructure including data centers, AI computing centers, telecom facilities and edge computing nodes. The company's technologies cover lithium-ion, lead-acid, hydrogen fuel cell and sodium-ion batteries, with comprehensive AIDC power solutions ranging from UPS battery systems and HVDC systems to MW-scale integrated backup power systems. With five global R&D and manufacturing bases and operations across more than 100 countries and regions, Vision Group has established an international network integrating R&D, manufacturing and services.

The REVO3.0 AIDC LFP Battery Backup Power System is a 600kW high-power lithium UPS cabinet developed by Vision Group for high-density backup power applications in AI data centers, featuring high-rate LFP cells.