Dual Validation of AIDC Backup Power & Energy Storage | Shoto Passes Two Large-Scale Fire Tests on the First Attempt

From large-scale outdoor energy storage to indoor AIDC backup power, Shoto has successfully passed two large-scale fire tests covering two different product systems and deployment scenarios, both on the first attempt.

Recently, Shoto’s DP60 high-rate lithium-ion battery system successfully completed a large-scale fire test (LSFT) for indoor AIDC backup power applications in accordance with UL 9540A-2026 (6th Edition), meeting all prescribed evaluation criteria on the first test. Earlier, Shoto’s liquid-cooled containerized energy storage system also passed a large-scale fire test for outdoor utility-scale energy storage applications on its first attempt. Together, the two tests cover different products and deployment environments and provide additional empirical evidence to support product selection and project safety assessments by high-end customers in North America.

Pushing Test Conditions to the Limit: Replicating Worst-Case Conditions in an AIDC Facility 

This test was conducted in strict accordance with UL 9540A-2026 (6th Edition) and benchmarked against stringent indoor LSFT requirements. Rather than relying on idealized laboratory conditions, the test reproduced, at full scale, the high-density, enclosed and high-load deployment conditions of an AIDC facility and simulated severe fault scenarios:

• Testing at 100% state of charge (SOC), reflecting the 24/7 high-load operating profile of AIDC facilities;

• Maximum-density cabinet arrangement, with cabinets positioned against the wall and zero spacing between adjacent cabinets, replicating a space-constrained deployment configuration;

• An enclosed-space configuration, reproducing the thermal boundary conditions associated with heat accumulation and restricted heat dissipation;

• A 98°C water-based fire-suppression activation threshold, making the test more stringent than the conventional 68°C threshold.

The test fully reproduced the thermal-runaway and combustion process of the battery cells. Measured results confirmed the system’s key safety performance: thermal runaway and open flames remained fully contained within a single cabinet; no fire propagation occurred between cabinets; no explosion was observed; and no re-ignition or high-voltage arcing was observed after the test. All evaluation criteria were met on the first attempt.

Designed around real-world engineering deployment, the test directly addresses the safety concerns most important to project owners, design institutes and EPC contractors. It demonstrates that, in enclosed, high-density AIDC facilities, DP60 can effectively contain thermal propagation, reduce the risk of fire spreading beyond the affected cabinet, support continuity of computing operations, and limit asset losses associated with downtime.

DP60 | Backup Power System for a Wide Range of AIDC Applications

AIDC computing workloads place three stringent requirements on backup power systems: high power, high reliability and high safety. These systems must deliver instantaneous high-power discharge within limited cabinet space to support uninterrupted computing operations. High-rate, instantaneous discharge can also cause rapid cell temperature rise and increase system overload risk, placing stringent requirements on cell performance, system architecture and safety-protection design.

Shoto’s DP60 high-rate lithium-ion battery system was developed specifically for the instantaneous high-power demands of AI computing infrastructure. It is designed to address backup-power safety and power matching in high-density AIDC environments, delivering coordinated advances in three key dimensions: power, space utilization and safety. 

High power density and space efficiency: Each cabinet occupies only 0.48 m while delivering up to 630 kW of output, equivalent to a power density of 1,312.5 kW/m. This substantially reduces the space required for backup power equipment, frees up valuable data-center floor area, and supports the trend toward compact, high-density deployment.

Simplified cell-based architecture for efficient integration and O&M: The system uses large-capacity cells to simplify series-parallel connection paths, reduce electrical connection points and streamline the overall system architecture, helping lower system losses and failure probability while improving system integration and on-site operation and maintenance efficiency.

Full-system testing for traceable, end-to-end safety validation: Large-scale system-level fire testing validates protective performance under extreme thermal conditions from the cell and module levels through the complete system, helping define clear product safety boundaries.

Computing Infrastructure: Safety as the Foundation, Real-World Testing First

Going forward, Shoto will continue to follow a “testing-first” product-validation philosophy, uphold safety as a fundamental requirement, focus on efficient operation, and deepen customer value. Through verifiable, deployable and repeatable safety technologies and high-performance products, the company will continue to strengthen the hardware foundation of global AI computing infrastructure, support the industry’s development toward higher quality, safety and efficiency, and create long-term, sustainable operating value for customers.