By Margaret Gross, Principal, Power Solutions LLC
Replacing A UPS? Time To Consider Li-Ion Batteries
When a UPS reaches end of life, the battery chemistry decision comes with it. Stick with VRLA? Or switch to Li-Ion? For many organizations, it’s a decision that’s frequently made on upfront price alone, without a complete picture of what each chemistry actually costs over time.
For most mid-market organizations with standard runtime requirements, Li-Ion’s total cost of ownership advantage is clear. And the safety concerns that keep many organizations on VRLA are based on the wrong lithium chemistry.
The TCO Case in Brief
The factors that drive Li-Ion’s TCO advantage are often evaluated incompletely:
- Battery Replacement Cycles: VRLA lasts 3–5 years. Li-Ion lasts 10 years. Most organizations replace VRLA batteries two to three times over a 10-year UPS lifecycle. Li-Ion typically requires no mid-cycle replacement at all.
- Floor space: Li-Ion battery cabinets run approximately 50% smaller than equivalent VRLA. In environments where space is priced per cabinet or per kW, that freed space has a direct dollar value. In enterprise data centers, it defers expansion cost.
- Maintenance visibility: VRLA degrades invisibly. A voltage check doesn’t reveal capacity loss — a battery string that passes can still have lost 30–40% of its rated runtime. Li-Ion’s integrated BMS monitors every cell continuously and reports through EcoStruxure IT in real time, at no additional infrastructure cost.
One Important Qualification
The TCO case above applies to standard runtime applications — where the UPS is sized to bridge a few minutes to generator start or ride through brief utility events. For sites requiring extended runtime, the larger battery string required narrows Li-Ion’s cost advantage, and VRLA may remain competitive. Sites with extended runtime requirements should contact us to help run a site-specific TCO analysis.
The Safety Question – Answered Accurately
The lithium battery incidents that get media coverage involve lithium cobalt oxide (LCO) or NMC chemistries — the formulations used in consumer electronics where energy density is the design priority. Those chemistries can produce thermal runaway under stress.
Schneider Electric UPS systems use lithium iron phosphate (LFP). LFP has a fundamentally more stable electrochemical structure — it does not produce the self-sustaining exothermic reaction that characterizes LCO and NMC incidents. The safety concern is real for lithium batteries in consumer electronics, but not in UPS applications. For LFP in a purpose-designed UPS system with a multi-layered BMS, the risk profile is well-documented and well-managed.
Where It Applies
Li-Ion battery options are available across Schneider Electric’s full UPS portfolio:
- Smart-UPS Ultra — compact single-phase rack and tower for smaller server rooms and edge locations
- Smart-UPS Modular Ultra (5–20 kW) — hot-swap modular single-phase with N+1 redundancy; Li-Ion native
- Galaxy VS, VL & VX (10–1,500 kVA) — three-phase systems for data centers and critical facilities at any scale
New Whitepaper Available
“Lithium-Ion UPS Batteries: A Complete Guide to TCO, Safety, and Making the Right Choice for Your Infrastructure” covers the full decision in depth — including a TCO model, third-party VRLA monitoring costs, chemistry comparison, retrofitting guidance, runtime considerations, sustainability factors, and an assessment of alternative battery chemistries. Read the full whitepaper.
Ready to work through the battery decision for your environment? Call 800-876-9373 or email [email protected] to discuss your environment and determine which battery chemistry is the right fit. Power Solutions provides battery health assessments, Li-Ion TCO analysis, retrofit compatibility reviews, and replacement planning for the full Schneider Electric UPS portfolio.
Margaret “Molly” Gross, Principal at Power Solutions, LLC, has over 15 years of experience in critical power for enterprise and government applications. She has extensive knowledge of UPS and data center infrastructure with a specialization in services and product lifecycle management. Molly closely follows emerging trends and innovations in the critical power industry with an eye for incorporating leading edge technologies into both new construction and legacy infrastructures. Connect with Molly on LinkedIn.