Fortress Power | eFlex 5.4kWh LFP Battery
Fortress Power | eFlex 5.4kWh LFP Battery is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
We offer fast and reliable shipping across the continental U.S., with free shipping available on most orders (exclusions may apply based on brand and product type). Orders are typically processed within 1–2 business days and transit time is usually 4–7 business days. Larger items may ship via freight and require a scheduled curbside delivery. Please ensure your contact details are accurate at checkout. For questions about delivery timelines, shipping eligibility, or special requests, feel free to contact us directly. See Policy.
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Fortress Power | eFlex 5.4kWh LFP Battery
The Fortress Power eFlex is a modular 5.4 kWh energy storage battery built using high-density, prismatic lithium iron phosphate (LFP) cells for enhanced safety and performance. It incorporates an advanced digital battery management system (BMS) featuring high-current contactor disconnects and closed-loop communication with compatible inverters. The BMS continuously tracks individual cell voltage and temperature while actively balancing cells to support long service life and dependable operation.
Communication via CANbus, Modbus, and Wi-Fi enables seamless integration with connected energy systems and remote monitoring platforms. The battery is housed in a sealed IP65-rated enclosure, protecting internal components from dust and water exposure from any direction. Multiple installation options—including wall mounting, floor mounting, and rack mounting—make the eFlex suitable for residential, commercial, and specialized applications such as marine, RV, mobile power, telecommunications, and railway systems.
Key Benefits
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Durable, long-life battery designed for daily cycling
-
Lithium iron phosphate (LiFePO₄) chemistry for enhanced safety
-
Up to 98% round-trip energy efficiency
-
Versatile mounting options for flexible installation
-
Remote monitoring and communication via Wi-Fi, Modbus, and CANbus
-
Battery management system monitors and balances individual cells
-
NRTL certified to UL 9540 and UL 9540A safety standards
Fortress Power | eFlex 5.4kWh LFP Battery
The Fortress Power eFlex is a modular 5.4 kWh energy storage battery built using high-density, prismatic lithium iron phosphate (LFP) cells for enhanced safety and performance. It incorporates an advanced digital battery management system (BMS) featuring high-current contactor disconnects and closed-loop communication with compatible inverters. The BMS continuously tracks individual cell voltage and temperature while actively balancing cells to support long service life and dependable operation.
Communication via CANbus, Modbus, and Wi-Fi enables seamless integration with connected energy systems and remote monitoring platforms. The battery is housed in a sealed IP65-rated enclosure, protecting internal components from dust and water exposure from any direction. Multiple installation options—including wall mounting, floor mounting, and rack mounting—make the eFlex suitable for residential, commercial, and specialized applications such as marine, RV, mobile power, telecommunications, and railway systems.
Key Benefits
-
Durable, long-life battery designed for daily cycling
-
Lithium iron phosphate (LiFePO₄) chemistry for enhanced safety
-
Up to 98% round-trip energy efficiency
-
Versatile mounting options for flexible installation
-
Remote monitoring and communication via Wi-Fi, Modbus, and CANbus
-
Battery management system monitors and balances individual cells
-
NRTL certified to UL 9540 and UL 9540A safety standards