BatteryJack inc. 12 Volt 55 AH UPS Replacement Battery AGM

Drop-in replacement for Gruber Power UPS

This 12 Volt 55 AH AGM battery is built as a direct 100% OEM replacement for Gruber Power units. The sealed, maintenance-free design uses absorptive glass mat technology to prevent electrolyte leakage in any mounting position. It is classified as non-spillable and meets International Air Transport Association requirements for safe transport.

Upgrades aging lead-acid cells

The advanced AGM construction controls gas generation and recombines over 90% of gas produced during normal operation. Expected service life reaches 4-7 years, making the jump worthwhile when existing batteries no longer hold a full charge or show reduced runtime. No watering or specific gravity checks are needed throughout the floating service life.

Limits of sealed AGM chemistry

The sealed case prevents electrolyte loss but also means cells cannot be topped up once capacity fades. Gas recombination handles over 90% of generated gas, yet sustained overcharging can still build pressure beyond the safety valve rating. Performance declines gradually after the 4-7 year design life, so plan replacement before critical backup time is compromised.