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Fortress Power - eFlex 5.4kWh LFP Battery

SKU eFlex54
Original price $3,120.00 - Original price $3,120.00
Original price
$3,120.00 - $3,120.00
Current price $3,120.00

Fortress Power - eFlex 5.4kWh LFP Battery

The Fortress Power eFlex is a 5.4 kWh scalable energy storage solution based on safe and energy dense prismatic Lithium Iron Phosphate cells. The digital processor Battery Management System (BMS) includes high amperage contactor disconnects and advanced Closed-Loop inverter communication, as well as individual cell voltage monitoring, temperature monitoring, and cell balancing to maximize reliability and longevity.

Canbus, modbus, and wifi communication enable internet-of-things compatibility. The IP65 case ensures direct water spray and dust will not penetrate the battery internals from all directions. The unit can be wall mounted, floor mounted, and server rack mounted for hard-to-reach access in renewable, marine, RV, mobile, telecom, railway applications and more.

Key Features

  • Rugged, Long-lasting, Daily Use Battery
  • Safe Lithium Iron Phosphate Technology (LifeP04)
  • 98% Round Trip Efficiency
  • Flexible Mounting Options
  • Remote Monitoring including wifi, modbus, and canbus
  • BMS Monitors & Balances Individual Cells
  • NRTL certified to UL9540 and UL9540a standards


Name eFlex 5.4
 Total Energy(kWh)  5.4
Max. Charge Current (Continuous) [A] 100
Max. Discharge Current (Continuous) [A] 60
Max. Pulse Current (for 5 sec) [A] 130
Capacity [Ah] 105
Voltage Range [V] 48-55
Charging Temperature [F] 32 to 113
Discharging Temperature [F] 32 to 140
Storage Temperature [F] 32 to 95
Dimension [L x W x H, inch] 21.5 x 17.5 x 7.2
Weight [lbs] 116
Life Cycles 8000 @ 80% DoD
Round Trip Efficiency >98%




eFlex Data Sheet
eFlex SPANISH Data Sheet
eFlex SPANISH Brochure

Installation Guides 

eFlex Owner / Installation Manual
Inverter Guides


UL9540 / UL1973 Certificate
UL9540a Large Scale Fire Test Report

Racking Details:

DuraRack Manual
Flexrack Technical Notes
Customer Server Rack Guide