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BatteryClerk Prime FAST 1-2 day shipping to most of the USA
BatteryClerk Prime FAST 1-2 day shipping to most of the USA

UPS Batteries

Power outages shouldn’t mean downtime for your business. At BatteryClerk, we provide a wide range of high-quality replacement batteries for UPS systems, designed to keep your critical equipment running seamlessly during unexpected power disruptions. Our inventory features top brands, and our team of experts is here to help you find the perfect battery for your specific UPS model. With unbeatable prices and fast, reliable shipping, BatteryClerk ensures your business stays protected and operational. Don’t let power interruptions slow you down—shop now and keep your operations running smoothly

  • Best Power 2.5KVA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 2.5KVA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

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    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power 3.0KVA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 3.0KVA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power 5.0KVA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 5.0KVA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power 1.15KVA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 1.15KVA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power 2.0KVA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 2.0KVA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power 500VA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 500VA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power 700VA 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power 700VA 12V 35Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59
  • Best Power Fortress LI 1.3KVA BAT-0058 12V 18Ah UPS Replacement Battery
    $53.39 - $53.39
    $53.39
    $53.39 - $53.39
    $53.39

    AJC Battery Compatible with Best Power Fortress LI 1.3KVA BAT-0058 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $53.39
    $53.39
    $53.39 - $53.39
    $53.39
  • Best Power Fortress Rack Mount LI 1020 BAT-0058 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power Fortress Rack Mount LI 1020 BAT-0058 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power Fortress II LI 1420 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power Fortress II LI 1420 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power LI 1420 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power LI 1420 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power LI 1420 Fortress II 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power LI 1420 Fortress II 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power 1420 Fortress II 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power 1420 Fortress II 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power 1.3KVA 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power 1.3KVA 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power 1420 Fortress 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power 1420 Fortress 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power Fortress LI 1420 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power Fortress LI 1420 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power Fortress LI 1420 II 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power Fortress LI 1420 II 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power Fortress Rackmount 1020 LI 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power Fortress Rackmount 1020 LI 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power BA-39 12V 18Ah UPS Replacement Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power BA-39 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • AJC Battery Compatible with Best Power FERRUPS FE-1.8K 12V 18Ah UPS Battery
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39

    AJC Battery Compatible with Best Power FERRUPS FE-1.8K 12V 18Ah UPS Battery

    In stock

    Information 12V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed...

    View full details
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39 - $58.99
    $53.39
  • Best Power Fortress LI 1800 BAT-0063 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power Fortress LI 1800 BAT-0063 6V 12Ah UPS Battery

    In stock

    Information 6V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed ...

    View full details
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power Fortress LI 2250 BAT-0063 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power Fortress LI 2250 BAT-0063 6V 12Ah UPS Battery

    In stock

    Information 6V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed ...

    View full details
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power LI 1800 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power LI 1800 6V 12Ah UPS Battery

    In stock

    Information 6V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed ...

    View full details
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power Fortress LI 950 BAT-0063 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power Fortress LI 950 BAT-0063 6V 12Ah UPS Battery

    In stock

    Information 6V SLA AGM | Premier OEM Replacement Battery by AJC® Maintenance-Free AGM Technology: No need to add acid or water, ever. Guaranteed ...

    View full details
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

Keep your data safe during emergencies and downtime with a UPS device. Just as important, keep your UPS device running with a reliable replacement or backup battery. BatteryClerk offers a wide range of affordable and reliable UPS replacement batteries for many top brands.

UPS Battery Replacement

UPS Battery Replacement

View our guide for installing UPS replacement batteries to ensure you get the most out of your new AJC brand battery.