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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 FERRUPS FE 2.1KVA 12V 18Ah UPS Replacement Battery
    $53.39 - $53.39
    $53.39
    $53.39 - $53.39
    $53.39

    AJC Battery Compatible with Best Power FERRUPS FE 2.1KVA 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...

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    $53.39 - $53.39
    $53.39
    $53.39 - $53.39
    $53.39
  • Best Power LI 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 LI 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...

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

    AJC Battery Compatible with Best Power LI 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 - $53.39
    $53.39
    $53.39 - $53.39
    $53.39
  • Best Power Patriot Pro 1000 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power Patriot Pro 1000 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 ...

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    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power Fortress LI 750 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 750 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 ...

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    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power Fortress 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 Fortress 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 Patriot SPS650 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power Patriot SPS650 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 ...

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    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power Patriot SPI600 6V 12Ah UPS Replacement Battery
    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79

    AJC Battery Compatible with Best Power Patriot SPI600 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 ...

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    $19.79 - $19.79
    $19.79
    $19.79 - $19.79
    $19.79
  • Best Power Micro-FERRUPS FE1.4KVA 12V 22Ah UPS Replacement Battery
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99

    AJC Battery Compatible with Best Power Micro-FERRUPS FE1.4KVA 12V 22Ah 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
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99
  • Best Power Ferrups FES850VA 12V 22Ah UPS Replacement Battery
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99

    AJC Battery Compatible with Best Power Ferrups FES850VA 12V 22Ah 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
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99
  • Best Power Ferrups FE2.1KVA 12V 22Ah UPS Replacement Battery
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99

    AJC Battery Compatible with Best Power Ferrups FE2.1KVA 12V 22Ah 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
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99
  • Best Power Ferrups FE1.8KVA FE 1.8KVA 12V 22Ah UPS Replacement Battery
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99

    AJC Battery Compatible with Best Power Ferrups FE1.8KVA FE 1.8KVA 12V 22Ah 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
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99
  • Best Power FE 2.1KVA BAT-0058 12V 22Ah UPS Replacement Battery
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99

    AJC Battery Compatible with Best Power FE 2.1KVA BAT-0058 12V 22Ah 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
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99
  • Best Power BAT0058 12V 22Ah UPS Replacement Battery
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99

    AJC Battery Compatible with Best Power BAT0058 12V 22Ah 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
    $58.99 - $58.99
    $58.99
    $58.99 - $58.99
    $58.99
  • Best Power Unity UT8K 12V 9Ah UPS Replacement Battery
    $27.19 - $27.19
    $27.19
    $27.19 - $27.19
    $27.19

    AJC Battery Compatible with Best Power Unity UT8K 12V 9Ah 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
    $27.19 - $27.19
    $27.19
    $27.19 - $27.19
    $27.19
  • Best Power Unity UT4K 12V 9Ah UPS Replacement Battery
    $27.19 - $27.19
    $27.19
    $27.19 - $27.19
    $27.19

    AJC Battery Compatible with Best Power Unity UT4K 12V 9Ah 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
    $27.19 - $27.19
    $27.19
    $27.19 - $27.19
    $27.19
  • Best Power Pro 1000 12V 75Ah UPS Replacement Battery
    $199.89 - $199.89
    $199.89
    $199.89 - $199.89
    $199.89

    AJC Battery Compatible with Best Power Pro 1000 12V 75Ah 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
    $199.89 - $199.89
    $199.89
    $199.89 - $199.89
    $199.89
  • Best Power Unity UT5K 12V 9Ah UPS Replacement Battery
    $27.19 - $27.19
    $27.19
    $27.19 - $27.19
    $27.19

    AJC Battery Compatible with Best Power Unity UT5K 12V 9Ah 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
    $27.19 - $27.19
    $27.19
    $27.19 - $27.19
    $27.19
  • Best Power Fortress Telecom 2250 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power Fortress Telecom 2250 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 Telecom 1800 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power Fortress Telecom 1800 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 1K 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power Fortress 1K 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 1050 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power Fortress 1050 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 FERRUPS FES-850 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power FERRUPS FES-850 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 FERRUPS 0800-2K 12V 35Ah UPS Replacement Battery
    $101.59 - $101.59
    $101.59
    $101.59 - $101.59
    $101.59

    AJC Battery Compatible with Best Power FERRUPS 0800-2K 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

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.