HiTHIUM Earns UL Certification for 6.25 MWh BESS Following World-First LDES Fire Test

HiTHIUM received UL Solutions certification for its ∞Power 6.25 MWh Battery Energy Storage System (BESS) at the ESIE 2026 exhibition, held in Beijing from April 1 to 3, 2026. The company also showcased its ∞Cell 1175Ah long-duration energy storage (LDES) battery. In a rapidly expanding battery storage market — as illustrated by Transgrid's procurement of 2 GW of batteries for the New South Wales grid and Recharge Power's 80 MWh storage order in Japan — large-scale safety validation is becoming a critical differentiator for LDES system manufacturers.

An Extreme Fire Test Conducted Under Independent Supervision

The fire test was conducted in accordance with UL 9540A (2025) and NFPA 855 (2026) standards, under the full supervision of UL Solutions and independent experts. Applied conditions included fully open container doors, minimal 15 cm spacing in a back-to-back and side-by-side configuration, 100% state of charge, and deactivation of active fire protection systems. Results showed the fire remained contained within a single container, with no thermal propagation between units. The enclosure maintained its structural integrity following the test.

HiTHIUM describes the test as the world's first open-door fire test of an LDES system equipped with kiloampere-hour (kAh)-level battery cells, establishing, according to the company, a new benchmark for system-level safety validation. Jiawu Chen, Fire Test Project Lead and Senior Fire Protection Design Engineer at HiTHIUM, presented the test design and execution during a certification ceremony held on the sidelines of the exhibition. The initiative aims, according to the manufacturer, to shift the industry from design-level safety to verifiable system safety.

UL Solutions Validates Compliance With Global Market Requirements

Chi Chen, APAC Senior Product Manager for Energy and Automation at UL Solutions, noted that the 6th edition of the UL 9540A standard, published in March 2026, now extends safety validation to full-container and system-level fire scenarios. The certification indicates, according to UL Solutions, that HiTHIUM's BESS meets stringent market access requirements across major global markets. It also validates the reliability of the system's passive safety design under real-world conditions.

On the sidelines of the exhibition, HiTHIUM organized interactive activities with ecosystem partners centered on the ∞Cell 1175Ah battery. These events combined a joint partner booth tour with a Lighthouse Factory-themed experience. The company indicates the activities attracted significant visitor engagement and in-depth interactions.

Chongqing Site Named World's First Lighthouse Factory for Energy Storage Batteries

In January 2026, HiTHIUM's Chongqing manufacturing base was recognized as the world's first Lighthouse Factory dedicated to energy storage batteries. The facility integrates over 40 digital solutions, including generative artificial intelligence, machine learning, and AIoT (artificial intelligence of things). These technologies cover the entire production cycle — from research and development to manufacturing and final testing — targeting high batch consistency, according to HiTHIUM.