Vertiv Liebert GXT (Gen-1) Replacement Batteries

About Vertiv Liebert GXT (Gen-1) Replacement Batteries

Replacement batteries for first-generation Liebert GXT UPS systems

This collection covers compatible replacement battery cartridges for the original (Gen-1) Emerson / Vertiv Liebert GXT family of double-conversion online UPS units. These were sold under both the Emerson Network Power and Liebert names, with model numbers in the GXT-1000, GXT-1500, GXT-2000, and larger GXT-T series, plus the matching battery packs such as GXT-36VBATT and GXT-96VBATT. As these units age, the internal batteries are the single most common part to fail and the part most often replaced.

Battery type and how it scales

The Gen-1 GXT line uses sealed lead-acid (SLA / VRLA) cells, almost always 12-volt blocks in the 7-7.2 Ah class, with some larger models using 9.0 Ah cells. A single UPS does not run on one 12V battery: the cells are wired in series into a string, so the total DC bus voltage scales with the model. Smaller 1000 VA units use a lower-voltage string, while larger rack/tower units stack more 12V blocks to reach 36V, 96V or higher. Because the cell count and arrangement differ by model, the right cartridge is defined by your exact unit, not by a single headline number.

Identify your battery by exact model

Do not order by appearance or by VA rating alone. Find the model number printed on the UPS rear or side label (for example, GXT-1000RT-120 or GXT-2000RT-120) and match it to the product in the grid below. Each product lists its compatible UPS model and the cell specification. If your label shows a variant suffix (RT, RX, MT, RTE, regional voltage codes), confirm it matches exactly before ordering — a 120V North American unit and a 230V international unit can look identical but take different packs.

Genuine OEM vs aftermarket

Vertiv sells genuine factory battery cartridges, which carry the OEM part number and a price premium. Aftermarket cartridges, like those in this collection, use equivalent-grade SLA cells assembled to the same form factor, connector, and capacity so they drop into the same tray. Both restore runtime; the practical differences are price, lead time, and warranty source. For an out-of-warranty UPS, a quality aftermarket pack is the common choice.

Battery lifespan

SLA UPS batteries typically last 3 to 5 years in service. Heat is the dominant factor: as a rule of thumb, battery life is roughly halved for every 8°C of sustained temperature above 25°C (77°F). A UPS in a hot closet or a poorly ventilated rack will need batteries sooner than one in a climate-controlled room. Watch for a shrinking self-test runtime or a UPS battery-fault alarm as the signal to replace.

Replacement steps

1. Confirm the exact model and order the matching cartridge.
2. Check whether your specific unit supports hot-swap before you start. Hot-swap behaviour varies across the Gen-1 GXT line: some rack/tower models accept a front-bay cartridge while the UPS keeps protecting the load, while other units — including the compact mini-tower (MT) models in this collection — require opening a screwed battery door or compartment per the manual and are not tool-less hot-swap. When in doubt, treat the unit as non-hot-swap: power down and transfer the load before servicing.
3. Release and slide out the old cartridge from the front bay, or open the battery compartment per the manual for your model.
4. Insert the new cartridge, seat the connector fully, and secure the retaining bracket, bezel, or battery door.
5. Let the UPS recharge fully, then run a self-test to confirm healthy runtime.
6. Recycle the old SLA batteries through a proper lead-acid recycling channel — do not landfill them.

Frequently asked questions

How do I know which pack fits my UPS? Match the exact model number on your unit's label to the compatible model listed on each product. The product grid shows the cell voltage and Ah for each item.

Are these genuine Vertiv batteries? No. These are compatible aftermarket replacement cartridges built to the same fit, capacity, and connector as the factory pack.

How long will a new battery last? Plan for 3 to 5 years, shorter if the UPS runs hot. Keeping the ambient temperature near 25°C maximizes life.

Can I replace the battery while the UPS stays on? It depends on your exact model. Some Gen-1 GXT rack/tower units support hot-swap and let you change the cartridge while the load stays protected; others, including the mini-tower (MT) units, use a screwed battery door and are not designed for hot-swap. Check your unit's manual first, and if you are unsure, power down and transfer the load before servicing.

Where does it ship from? Orders ship from our Canadian warehouse.

Liebert, GXT, Emerson, and Vertiv are trademarks of Vertiv Group Corp. UPSPLUSBATTERY.ca is not affiliated with, endorsed by, or authorized by the manufacturer; aftermarket batteries are compatible replacements.