E-STORAGE's KuBank 3.0 for C&I Applications Successfully Passes Large-Scale Fire Testing

Canadian Solar Inc. (the "Company" or "Canadian Solar") (NASDAQ: CSIQ) announced that e-STORAGE, its energy storage solutions business, has successfully completed Large-Scale Fire Testing (LSFT) for its KuBank 3.0 commercial and industrial (C&I) energy storage system under the latest UL 9540A:2026 standard, becoming the industry's first to pass this rigorous large-scale fire test.

KuBank 3.0 delivers up to 940 kWh of energy capacity in a single liquid-cooled cabinet. Built with advanced 314 Ah LFP battery cells, it supports flexible 400V, 690V, and 800V architectures, offers integrated load connection, enables seamless transitions between grid-connected and islanded operation, and holds comprehensive international certifications.

The LSFT is a rigorous system-level safety evaluation designed to assess how an energy storage system behaves under extreme fire conditions, including whether fire can be contained within the tested unit and prevented from propagating to adjacent systems. For customers, this validation is critical because it provides third-party visibility into fire safety performance, supports permitting and project approval processes, and helps reduce deployment risk in C&I environments.

Conducted under highly demanding conditions, the test evaluated a fully charged 940 kWh system with thermal runaway intentionally initiated and all fire suppression systems disabled. During the approximately four-hour fire event, no explosion occurred, the cabinet structure remained intact, and no fire propagation was observed in neighboring units. KuBank 3.0 passed the test on its first attempt without corrective actions, validating its advanced safety performance under the latest UL 9540A:2026 standard. The test was witnessed and independently verified by both TÜV Rheinland, the testing agency, and Energy Safety Response Group (ESRG), a fire safety consultant.

Designed with an independent physical compartment architecture, high-strength fire-resistant construction, and advanced thermal insulation materials, KuBank 3.0 enhances fire safety performance at the system level. Its intelligent liquid-cooling system maintains battery temperatures within the optimal operating range with a temperature deviation of ≤3°C, while its multi-layer active safety architecture integrates zone isolation, early thermal runaway monitoring, multi-stage fire detection, and protection technologies to support safe and reliable operation.

Jeff Roy, President of e-STORAGE, said, "Passing this large-scale fire test on the first attempt demonstrates the strength of KuBank 3.0's safety-first design. As safety standards continue to evolve, customers need energy storage solutions that have been validated under the most demanding real-world conditions. This achievement provides greater confidence in the safe deployment of KuBank 3.0 across C&I applications."

KuBank 3.0 has entered mass production and is now available to customers worldwide.

Canadian Solar | www.canadiansolar.com

e-STORAGE | www.csestorage.com