BatteryJack inc.
BatteryJack inc. PowerStar RBC51 Replacement Kit 12V 9.0Ah
Replacement kit with two 12V 9.0Ah AGM batteries, 100% compatible with RBC51 UPS units and offering higher capacity than 7.5Ah originals
- Increased capacity with 9.0 Ah AGM design
- Sealed construction prevents electrolyte leakage in any position
- Maintenance-free operation eliminates water topping or checks
- 100 % OEM-compatible fit for RBC51 UPS units
- Expected service life of four to seven years
Replacement Kit for RBC51 UPS
The PowerStar RBC51 replacement kit supplies a 12 V, 9.0 Ah AGM battery set designed for uninterruptible power supplies and backup devices. It arrives new and ready to install, using sealed absorptive glass mat construction that prevents electrolyte leakage in any orientation. The kit is classified as non-spillable and meets International Air Transport Association requirements for safe transport.
Upgrade from 7.5 Ah units
The kit replaces original RBC51 batteries that are typically rated at 7 Ah or 7.5 Ah, increasing capacity to 9.0 Ah through advanced AGM technology. The jump is worth it when longer runtime during outages is needed without changing the physical footprint. Dimensions are 5.94 length, 2.56 width and 3.66 height with T1/T2 terminals for direct fit.
Suits UPS owners needing more runtime
This kit suits users who want a maintenance-free, 100 per cent OEM-compatible replacement that improves capacity over the original cells. It is not for buyers who need a different voltage, a larger case size, or a chemistry other than sealed AGM. The three-year warranty on UPS and backup devices covers the intended application.
Highlights
- Increased capacity with 9.0 Ah AGM design
- Sealed construction prevents electrolyte leakage in any position
- Maintenance-free operation eliminates water topping or checks
- 100 % OEM-compatible fit for RBC51 UPS units
- Expected service life of four to seven years
Specifications
No published specifications for this item yet.
Questions about this item
Will the 5.94 x 2.56 x 3.66 inch case fit my existing RBC51 battery compartment?
The kit measures 5.94 inches long, 2.56 inches wide and 3.66 inches high, matching the standard RBC51 footprint for a direct fit.
How do I connect the T1/T2 terminals without damaging the posts?
Slide the supplied terminal adapters onto the T1/T2 posts, tighten the bolts by hand then give a quarter turn with a spanner — over-torquing cracks the seal.
When should I plan to replace the 9.0 Ah AGM cells?
Expect four to seven years of service; swap the pack when runtime drops below half of the original 9.0 Ah capacity.
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