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Fortress Power

Fortress Power – Advanced Lithium Battery Storage for Home and Business

Take control of your energy with Fortress Power lithium battery systems, engineered for reliable whole-home backup, solar self-consumption, and scalable off-grid solutions. Built with premium-grade LiFePO₄ cells, Fortress batteries deliver long life, high efficiency, and unmatched safety — ideal for residential, commercial, or industrial energy storage.

Whether paired with a solar system or used as a standalone backup solution, Fortress Power ensures peace of mind with robust performance and U.S.-based support.

Browse our Fortress Power collection to build a smarter, safer energy storage system today.

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    Fortress Power

    Fortress Power eFlex 5.4kWh G2 Lithium Iron Phosphate (LFP) Battery with Wall Mount Bracket | 10 Year Warranty

    $2,495.00
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    Fortress Power

    Fortress Power | eForce Cover for Batteries

    $270.00
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    Fortress Power

    Fortress Power | eForce Wallmount Bracket

    $215.00
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    Fortress Power

    Fortress Power | eForce eWay and Base for AC and DC wire management and floor mount

    $1,099.00
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    Fortress Power

    Fortress Power 600Ah eForce 28.8kWh Stackable Lithium Iron Phosphate Battery

    $11,299.00
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    Fortress Power

    Fortress Power 400Ah eForce 19.2kWh Stackable Lithium Iron Phosphate Battery

    $7,895.00
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    Fortress Power

    Fortress Power 200Ah eForce 9.6kWh Stackable Lithium Iron Phosphate Battery

    $4,555.00
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    Fortress Power

    Fortress Power FlexRack Combining Rack for eFlex 5.4 kWh Lithium Batteries

    $2,030.00
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    Fortress Power

    Fortress Envy 12kW Inverter with 4 eFlex G2 5.4kWh Batteries and Durarack Bundle

    $16,999.00
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    Fortress Power

    Fortress eVault 18.5 kWh Battery and Envy 12kW Inverter Bundle

    $14,999.00
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    Fortress Power

    Fortress Envy 12kW Hybrid Inverter, 4 eFlex G2 5.4 kWh Lithium Batteries, Durarack Enclosure and Guardian Battery Monitoring Bundle

    $17,199.00
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    Fortress Power

    Fortress Envy 12kW Inverter and 4 eFlex G2 5.4 kWh Lithium Batteries Bundle

    $15,699.00
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    Fortress Power

    Fortress Envy 12kW Inverter with 18.5 kWh eVault Battery and Guardian Battery Monitoring Bundle

    $15,199.00
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    Sol-Ark

    Sol-Ark 15K + Fortress Power eFlex Battery + Fortress Durarack Enclosure Bundle

    $24,699.05
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    Sol-Ark

    Sol-Ark 12K + Fortress Power eFlex Battery + Fortress Durarack Enclosure Bundle

    $21,849.05
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    Fortress Power

    Fortress Power APSmart Duo RSD-D-20

    $99.00
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    Fortress Power

    Fortress Power FlexTower with Envy True 12 kWh Inverter and 4 eFlex 5.4 kWh LFP Batteries

    $18,663.00
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    Fortress Power

    Fortress Power FlexTower with Envy True 12 kWh Inverter and 3 eFlex 5.4 kWh LFP Batteries

    $16,080.00
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    Fortress Power

    Fortress Power Flex Tower Inverter + Battery Enclosure

    $3,088.00
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    Fortress Power

    Fortress Power FlexTower-Inverter Enclosure IP 65 outdoor rated

    $1,366.00
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    Fortress Power

    Fortress Power DuraRack with 4 eFlex 5.4kWh G2 Lithium Iron Phosphate (LFP) Batteries with Wall Mount Bracket

    $11,698.00
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    Fortress Power

    Fortress Power DuraRack with 3 eFlex 5.4kWh G2 Lithium Iron Phosphate (LFP) Batteries with Wall Mount Bracket

    $9,115.00
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    Fortress Power

    Fortress Power DuraRack Without Battery

    $1,366.00
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    Fortress Power

    Fortress Power Guardian Battery Monitoring

    $499.00
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