CSI's 2.3 MWh Mobile BESS Earns TÜV Certification to Applicable UL 9540 Requirements

LIVERMORE, Calif., Sept. 22, 2026 /PRNewswire/ -- Coulomb Solutions Inc. (CSI), a leading provider of commercial electrification and mobile energy storage solutions, today announced that TUV has certified CSI's 2.3 MWh Mobile BESS base model eBESS2.3-1.0-01 is compliant with applicable UL 9540:2023 requirements, marking an important milestone in the continued commercialization and deployment of CSI's high-capacity mobile energy storage systems.

TÜV Rheinland conducted a field evaluation, inspection, testing, and applicable technical assessment of CSI's 2.3 MWh base model and confirmed compliance with the applicable requirements of UL 9540:2023, the Standard for Energy Storage Systems and Equipment. UL 9540 is the recognized system-level safety standard for Energy Storage Systems (ESS), evaluating the system as an integrated unit; including batteries, power conversion equipment, controls, enclosures, protection systems and other critical components.

UL 9540:2023 certification addresses the safety of the complete energy storage system, including:

• System-Level Safety: Evaluation of the batteries, power-conversion equipment, enclosure, controls, protection systems, and associated equipment as one integrated operating system. This includes pack, cell, and unit fire testing per the stringent UL9540A procedure.
• Component Safety Standards: Evaluation of applicable component-level safety requirements, including standards such as UL 1973 for battery systems and UL 1741 for inverters, converters, and associated power-conversion equipment.
• Electrical and Mechanical Protection: Evaluation of electrical, mechanical, thermal, and other potential system hazards.
• Controls and Communications: Assessment of system protection, charging and discharging controls, communications between system components, fault response, and other critical operating functions.
• Environmental and Enclosure Safety: Evaluation of system materials, enclosures, environmental protection, and other features intended to support safe operation of the equipment. 

"Achieving UL 9540 certification for our 2.3 MWh Mobile BESS base unit represents another major milestone for CSI and, more importantly, for our customers," said David Mazaika, CEO of Coulomb Solutions Inc. "Customers deploying large mobile energy storage systems need confidence not only in performance and reliability, but also that the complete system has been evaluated against rigorous safety standards. UL 9540 certification provides that additional level of assurance."

CSI's 2.3 MWh Mobile BESS is designed specifically for applications where additional electrical capacity is required but sufficient permanent grid infrastructure is unavailable, delayed or uneconomical. The system combines approximately 2.3 MWh of energy storage with an integrated 1 MW power conversion system providing 480VAC power. This allows customers to rapidly deploy substantial electrical capacity for applications including commercial fleet and heavy-duty EV charging, data centers and high-load facilities, construction and remote work sites, utility and grid-support applications, peak shaving and demand-charge management, entertainment or sporting events and other temporary-power applications.

Unlike conventional stationary BESS installations, CSI's Mobile BESS systems are engineered for frequent transport and deployment, using commercial vehicle-grade LFP battery technology, integrated thermal management and a rugged system architecture.

CSI also recently announced an optional bidirectional Megawatt Charging System (MCS) configuration for its next generation model eBESS2.3-1.0-02 MWh Mobile BESS. This enables the system to provide up to one megawatt of high-power charging to compatible commercial electric vehicles and equipment. This configuration will also go through the full suite of UL testing as well.

"Grid capacity is one of the biggest barriers to electrification," Mazaika added. "Our goal is to help commercial EV fleets, construction firms, sports and entertainment venues, data centers and other customers access to safe, certified power where they need it—without waiting years for permanent infrastructure upgrades. Achieving UL 9540 certification is an important step toward enabling those deployments at scale."

About Coulomb Solutions Inc. (CSI)
Coulomb Solutions Inc. (CSI) provides transportable Battery Energy Storage Systems (BESS), advanced battery systems for commercial electric vehicles, low-voltage batteries and electrification components for the North American commercial vehicle market. CSI's Mobile BESS solutions deliver scalable, rapidly deployable power for fleet charging, commercial and industrial operations, grid support, temporary power and other applications requiring flexible electrical capacity. CSI's mission is to accelerate commercial electrification while providing innovative energy storage solutions that help customers overcome electrical infrastructure constraints.

For more information, visit www.coulombsolutions.com

For BESS Inquiries Contact:
Greg Laudermilch
Vice President of Sales and Marketing - BESS
Coulomb Solutions Inc., (CSI)
[email protected]
1-916-360-0015

Media Contact:
Paul Rivera
Chief Commercial Officer
Coulomb Solutions Inc. (CSI)
[email protected]
734-272-2934

SOURCE Coulomb Solutions Inc.