Huawei's Smart String & Grid Forming ESS Triumphs in Extreme Ignition Test

[Shenzhen, China, February 21, 2025] Huawei Digital Power's Smart String & Grid Forming Energy Storage System (ESS) has successfully passed the extreme ignition test, witnessed by customers and DNV, a globally recognized independent organization in assurance and risk management. This groundbreaking test, conducted under real-world scenarios and innovative methodologies, validates the ESS's capabilities in extreme conditions, marking a significant milestone in advancing safety standards for the energy storage industry.

Verification in Extreme Conditions: All-Scenario Ignition Test

Aligned with the international standard UL 9540A test method, Huawei Digital Power elevated the rigor of the test by significantly increasing the number of cells subjected to thermal runaway. This approach comprehensively verified the safety protection capabilities of the Smart String & Grid Forming ESS in extreme ignition scenarios, setting a new benchmark for safety testing.

Highlight 1: Real-World Verification with 100% Mass-Produced Products

The test was conducted under conditions that strictly mirrored real-world applications. Four Smart String & Grid Forming ESSs (containers A, B, C, and D) were actual mass-produced products. Charged to 100% state of charge (SOC), they were deployed according to the minimum maintenance and safety clearances required for a plant. The entire test process was spontaneous, with no manual intervention, ensuring a realistic and comprehensive system-level extreme verification environment.

Highlight 2: Triggering 12 Cells into Thermal Runway Causes No Fire or Explosion after Multiple Ignition Attempts

In conventional ESSs, thermal runaway in a single cell often leads to the release of combustible gases into the container, resulting in fire or explosion. However, in Huawei's Smart String & Grid Forming ESS (container A), thermal runaway occurred in 12 cells without incident. The system's innovative combined defense mechanism—positive pressure oxygen barrier and directional smoke exhaust duct—effectively vented combustible gases. Manual ignition did not trigger fire or explosion, and the safety issue was automatically resolved. This demonstrates the ESS's ability to prevent fire and fault spread at the battery pack level.

Highlight 3: Ultimate Fire Resistance Capability Prevents Propagation under Maximum Oxygen Supply Combustion Scenario

To simulate large-scale burning scenarios, the test progressively increased the number of thermal runaway cells until the entire battery pack was affected while providing maximum oxygen supply to create stricter combustion conditions. Despite these challenges, the highest cell temperature in adjacent containers B, C, and D reached only 47°C—far below the thermal runaway threshold. Post-test disassembly confirmed the integrity of the ESS body, fire-resistant layer, and internal battery packs, proving the system's resilience in extreme scenarios.

Highlight 4: Slow Fault Progression Provides Critical Time for Early Intervention to Avoid Serious Accidents

A conventional ESS risks immediate fire or explosion upon thermal runaway in a single cell, often leading to severe accidents. In contrast, Huawei's ESS (container A) delayed fire ignition for 7 hours in extreme scenarios, even as the number of thermal runaway cells increased. This slow fault progression allows emergency personnel ample time for early intervention, mitigating risks and ensuring the safety of personnel and property.

Technical Breakthrough: Redefining ESS Safety Logic

ESS safety is critical to the sustainable and high-quality development of the renewable energy industry. The success of this test underscores Huawei Digital Power's major breakthrough in system safety, delivering comprehensive protection from the battery cell level to across the entire system. Through architectural innovation, the company has enhanced the safety protection mechanism of the ESS from the container level (industry standard) to the pack level, effectively preventing thermal runaway spread.

By leveraging safety verification experience to formulate industry standards, Huawei Digital Power is fostering the healthy and high-quality development of the energy storage industry. This effort supports the creation of safer energy infrastructure for new power systems, ensuring a sustainable energy future.

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