Great Power Successfully Completes Full‑Scale Fire Test for 5MWh Liquid‑Cooled Container BESS

Great Power has successfully completed a full-scale fire test with its Max-20HC-5000 DC liquid-cooling container battery energy storage solution, which features 314 Ah LFP battery cells and has a rated energy capacity of 5 MWh.

The test focused on the system-level fire safety performance of Great Power’s system and was conducted with reference to ANSI/CAN/UL 9540A:2026.

Full-Scale Fire Test Overview

The test was designed to simulate a worst-case field failure scenario: the battery system was charged to 100% State of Charge (SOC), the container doors were closed, and the active fire suppression system was manually disabled. Thermal runaway and fire were intentionally triggered in one of the battery modules.

- Fourteen cameras were deployed—seven inside the burning container and seven outside—to continuously record the impact of flames and heat on surrounding equipment and building structures.

- A highly challenging installation spacing was adopted: the minimum gap between the two containers was only **150 mm**; the burning container faced another energy storage unit, and a test wall was positioned 3,000 mm away from the electrical compartment.

- Cell temperatures inside the adjacent container were monitored throughout the test to verify whether thermal isolation and heat dissipation paths could prevent the spread of the hazard.

Flame propagation, the occurrence of secondary thermal runaway, and the structural integrity of the container were observed throughout the test. Monitoring continued after ignition until the fire subsided;

the fire **extinguished itself after 16 hours**, and a test certificate was ultimately issued by TÜV Rheinland.

Key Test Results

                       The battery test from Cell to the whole installation for the fire suppression test.

• Flame and thermal runaway was confined inside the initiated battery module at the early test phase.
• Peak cell temperature inside neighboring container stayed under 70°C, far below critical cell gas venting temperature threshold, adjacent modules had no thermal-runaway triggered.
• Optimized internal heat-dissipation architecture enables this containerized liquid-cooled BESS to trap thermal-runaway hazard within single unit, avoiding domino-effect disaster for multi-container energy storage power stations.
• Zero fire propagation to adjacent energy storage containers, no structural collapse occurred throughout the full scale fire safety test.

What does this fire test mean for energy storage projects?

1. Component-level simulation or small rack tests cannot fully replicate the hazards of large-capacity containerized energy storage systems. 
2.  Full-scale UL9540A fire testing delivers real field data for EPCs, project owners, insurers and grid regulators.
3.  Energy storage systems that pass this rigorous full-scale fire test simplify permitting and reduce safety spacing requirements at utility-scale and commercial energy storage parks, improving land utilization for solar-plus-storage projects.

Great Power’s Expertise in Energy Storage Safety

According to Frost & Sullivan, Great Power ranked No. 1 globally in residential energy storage battery shipments in H1 2026, with a 28% market share.

In recent years, the company has expanded its scope to produce not only LFP batteries, but also solid-state and sodium-ion batteries for applications from homes to AI data centers.

Great Power’s energy storage cell manufacturing is over 95% automated to ensure consistency and reliability, with flexible packaging and integration lines to enable customized solutions for its customers.

In 2025, the company obtained the EN 9100:2018 Aerospace and Defense Quality Management System Certification from TÜV Rheinland Greater China for its Zhuhai manufacturing base,

confirming that the company’s quality management system meets the requirements of EN 9100:2018 and is registered in the IAQG OASIS database.

Summary

The successful full-scale fire test marks another milestone for Great Power’s liquid cooled container BESS.

As energy storage safety requirements continue to tighten globally, full-scale fire testing will become a key benchmark for selecting reliable container energy storage solutions.

Backed by Great Power’s high automation battery manufacturing capacity, diversified product portfolio covering residential, commercial/ industrial and data-center-grade storage solutions, and authoritative quality certifications such as EN 9100:2018, this fire-test milestone reinforces the competitiveness of Great Power’s liquid-cooled container BESS amid tightening global energy storage safety standards.

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