The Runaway Review
Detailed reviews of battery chemistries and their advantages and disadvantages in the UPS industry.
From the Lab to the Rack: The Safety-Driven Design of Samsung SDI’s Lithium-ion Batteries
SEPTEMBER 26, 2025
In 2017, Samsung SDI reshaped the North American UPS landscape, making waves with the introduction of their advanced lithium-ion batteries.
By combining Lithium Manganese Oxide (LMO) and Lithium Nickel Manganese Cobalt Oxide (NMC) chemistries, Samsung SDI delivered a game-changing solution—one that redefined fast charging, high-current discharging, and robust energy capacity for the future of reliable backup power.
Prioritizing Lithium-ion Battery Safety
Safety is always the top priority when it comes to backup power. Our customers trust the unwavering safety of Mitsubishi Electric’s UPS systems—not only in terms of fire and environmental protection but also protection against the immense financial losses a power outage can cause.
Mitsubishi Electric ensures that every lithium-ion battery system we offer, including those from Samsung SDI, meets rigorous industry UPS lithium-ion safety regulations and standards, such as UL 1973, UL 9540, and UL 9540A.
Early on, however, integrating advanced lithium-ion batteries into North American UPS systems required adaptation and refinement—challenges that persist today for many battery industry players.
A major turning point came in 2017, when Mitsubishi Electric introduced the first 1.2-2MW double conversion UPS for the data center industry using Samsung SDI’s advanced lithium-ion battery. This deployment required both innovative engineering and rigorous testing to ensure reliability.
Integrating lithium-ion batteries into UPS systems introduced new operational challenges, particularly around conditional discharge and charging protections managed by sophisticated battery management system (BMS) signals. Comprehensive data monitoring and management also became essential for performance guarantees and warranties.
Working alongside Samsung SDI, we led the way in thorough research and strenuous product testing — a process that established benchmarks we continue to uphold for all lithium-ion and alternative high-power battery chemistries.
By 2019, our joint innovation and testing efforts culminated in one of the UPS industry’s most notable success stories: marrying Mitsubishi Electric’s highest-kW UPS with Samsung SDI’s most powerful battery for a backup solution that set new standards in reliability and performance.
Key Lithium-ion Battery Safety Features
Let’s take a closer look at the technology inside Samsung SDI’s LMO/NMC battery modules.
Samsung SDI cell chemistry has a spinel cathode crystal structure with a distinguishing feature of having a low heat flow (~439J/g). This property raises the thermal ignition point, reducing thermal runaway risks and delivering a product that is as stable and safe as it is powerful—well-suited for high-power UPS systems pushing beyond 1MW.
Each rugged aluminum-encased prismatic cell is crafted under strict design and manufacturing standards that include laser welding and gas venting—features that optimize both durability and safety.
Inside, high-performance cells are layered with thermal insulation and integrated fire suppression sheets, which contain burst capsules filled with fire-extinguishing agents. These modules are fully accessible from the front of the rack for simplified service and maintenance.
The integrated sensors (thermal, voltage, current) continuously communicate with the module’s BMS, sending data to a central rack System Mode Power Supply Assembly, which houses the system BMS and supplies power to both the BMS and the battery control unit.
To further enhance lithium-ion safety, each Samsung SDI battery rack features fast-acting, removable fuses that reduce string voltage and current during service; a molded case breaker rated to 65kA; and UL-listed components.
Manufacturing Excellence Brings Superior Reliability
In addition to strong cell chemistry and integrated BMS, Samsung SDI’s industry-leading lithium-ion battery safety is the result of an uncompromising commitment to quality at every stage. Over 2,000 checkpoints are built into their manufacturing process.
Cell-level inspections include:
- Winding alignment
- Detection of shorts between anode and cathode
- X-ray measurements for can-to-jelly-roll distance
- Computed tomography (CT) scans to ensure precise electrode alignment
Before module assembly, each cell box undergoes an impact shock test, followed by both visual and low- resistance inspections of the busbar welds to confirm contact integrity.
Intelligent Battery Management: The Heart of Protection
A defining factor in Samsung SDI’s success is its intelligent, multi-layered BMS, which employs comprehensive protection protocols such as real-time measurement, passive and active controls, and high-sensitivity thermal monitoring.
For large 1–2MW UPS systems, meticulous EMI noise and voltage ripple filtering is critical for reliable BMS sensor readings.
Mitsubishi Electric’s battery testing team thoroughly tested these aspects, working hand-in-hand with Samsung SDI to ensure that their filtering systems meet both UPS lithium battery regulations and the high standards required for high performance data center environments.
Proven Performance and Reliability
Every facet of the Samsung SDI battery system—from cell design and advanced thermal management to rigorous BMS protocols—has earned recognition across the UPS industry.
Our partnership with Samsung SDI has yielded UL 9540 system listings and compliance with the strictest AHJ (Authority Having Jurisdiction) requirements throughout North America.
The result? The most reliable and safe backup power solution powering data centers today:
99.9995% UPS Reliability & Zero Thermal Runaway Incidents in Normal Operation
Through relentless innovation and uncompromising quality control, Mitsubishi Electric and Samsung SDI are redefining what’s possible in UPS battery solutions to deliver high performance, safety, and reliability to the most critical data center operations.
Wondering if Samsung SDI’s Lithium-ion Battery is right for you?
Samsung SDI’s lithium-ion battery is compatible with Mitsubishi Electric UPS systems ranging from 10kVA to 2MW. Let’s talk about your specific power demands and unlock new levels of reliability!
Edited by Matt Slippy, Marketing Specialist & Nicole Kristof, Senior Marketing Specialist
Stay up-to-date on industry trends & insights
Get the critical power insights you need to keep your business from going dark.
By submitting this contact form, you agree that a representative(s) of Mitsubishi Electric Power Products, Inc. (MEPPI) may contact you using the information you provided. In accordance with our Privacy Policy, we will never share or sell your personal data.
Follow us on social media
