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Small rectangular sealed lead-acid battery with two terminals

BatteryJack inc.

BatteryJack inc. 6V 5Ah UPS Replacement Battery for UB645 4.5Ah

SKU CH-P2QJ-YEPHW

A 6 V 5 Ah sealed AGM battery that replaces 4.5 Ah UB645 units in UPS systems

  • Higher 5 Ah capacity extends runtime over standard 4.5 Ah units
  • Advanced AGM technology delivers spill-proof sealed construction for safe operation
  • 100 % OEM replacement matches UB645 645 64 90 905 specifications exactly
  • Maintenance-free design requires no water checks or electrolyte service
  • Expected 4 to 7 year service life under normal float conditions

Drop-in 6V UPS battery upgrade

This 6V sealed lead-acid battery delivers 5Ah capacity as a direct replacement for the UB645 4.5Ah unit. It uses absorptive glass mat construction that prevents electrolyte leakage in any mounting position. The maintenance-free design requires no water checks or specific-gravity readings during its service life. Over 90% of internally generated gas is recombined for safe, non-spillable operation.

Ideal for longer runtime in existing UPS units

The higher 5Ah rating suits owners who want extended backup time without changing enclosures or wiring. Buyers who need a different voltage or a lower-profile case should look at other models. The battery is classified non-spillable for air transport, so it meets IATA shipping requirements. It is not suited for applications that demand a 4.5Ah form factor or alternative chemistries.

5Ah capacity versus 4.5Ah original

The single specification that decides fit is the 5Ah rating at 6V, which exceeds the original 4.5Ah UB645 rating. This increase provides more stored energy in the same footprint and terminal layout. Verify that your UPS charger accepts the slightly higher capacity before installation. The 6V 5Ah figure is the decisive compatibility number.

Highlights

  • Higher 5 Ah capacity extends runtime over standard 4.5 Ah units
  • Advanced AGM technology delivers spill-proof sealed construction for safe operation
  • 100 % OEM replacement matches UB645 645 64 90 905 specifications exactly
  • Maintenance-free design requires no water checks or electrolyte service
  • Expected 4 to 7 year service life under normal float conditions

Specifications

No published specifications for this item yet.

Questions about this item

What comes in the box with this 6 V 5 Ah battery and what must be purchased separately?

The package contains the sealed AGM battery only; terminal hardware, cables or mounting brackets are not included and must be sourced separately.

Should I choose the 5 Ah version or the 4.5 Ah UB645 version for my UPS?

The 5 Ah model is a direct higher-capacity replacement for the UB645 4.5 Ah unit and fits the same footprint.

What does the 5 Ah rating mean once the battery is installed in my UPS?

It delivers a 5 ampere-hour capacity at 6 volts, providing longer runtime than the original 4.5 Ah cell under identical load conditions.

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