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Fortress Power eFlex 48V Lithium Battery (5.4kWh | 105Ah)

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Manufacturer Warranty Included
SKU EFLEX5.4
Save 40% Save 40%
Original price $3,850.00
Original price $3,850.00 - Original price $3,850.00
Original price $3,850.00
Current price $2,329.00
$2,329.00 - $2,329.00
Current price $2,329.00
Availability:
Low stock
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For the policy to apply, please send us a screenshot, link, or any other evidence of the product being priced lower than oursĀ before making the purchase.

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Refunds & Returns Policy

We offer a 30 day return for this product from date of receipt. All returns must be pre-approved and issued an Return Merchandise Authorization (RMA) #. All RMAs will be closed if the product is not recevied within 30 days. The return shipping fees are the responsibility of the customer. Returns are subject to a restocking fee. Returns are only allowed if the products are in their original shipping cartons with proper packaging in place and be in re-sellable condition.

Refer to our Refunds & Return Policy for more details.

Shipping & Delivery

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Please allow 1-3 days for processing your order.

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We ship to the lower 48 continental United States only at this time.

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Delivery time

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Fortress Power eFlex 48V Lithium Battery (5.4kWh | 105Ah)

Description

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

Product Specifications

Fortress Power eFlex 48V Lithium Battery (5.4kWh | 105Ah) Product Specifications

General
Name eFlex 5.4
Ā Total Energy(kWh) Ā 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%

Product Manuals

Datasheets

eFlex Data Sheet
eFlex SPANISH Data Sheet
eFlex SPANISH Brochure

Installation Guides / Warranty

eFlex Owner / Installation Manual
Inverter Guides
FirmwareĀ 
Warranty

Certifications

UL1973 Certificate
OGPe Certification
Flextower/Durarack UL 9540

Racking Details

DuraRack Manual
Flexrack Technical Notes
Customer Server Rack Guide

Product Warranty

Warranty

Product FAQs

Fortress Power Product FAQs

1) Does energy storage work well with my solar system?

Yes. On the grid? Absolutely! Energy storage adds a lot of value to your solar systems. It keeps your solar system operating when your utility service is interrupted. Without energy storage, your PV system will be forced to shutdown when the grid is off.

If you live off grid, energy storage enables you to use the clean solar energy to power your home day and night.

Fortress Power also knows you’re a fan of conservation—energy storage saves both your surplus solar energy and your cash since it reduces on grid energy dependence.

2) Can I use energy storage without solar panels?

Absolutely. For on grid clients, a homeĀ energy storage unitĀ Ā stores energy from your electricity provider. If an outage occurs, homeĀ energy storage canĀ provide up to 24 hours of potentially life-saving power. Need more reassurance? Fortress Power offers batteries with larger storage capabilities, completely customizable to your needs. And, like you, we appreciate saving money. When electricity is at its lowest daily rate, ourĀ smartĀ energy storage unitsĀ use that period to charge. When peak electric use occurs, ourĀ energy storage unitsĀ can discharge power to suit your lifestyle.

3) What about power outage protection?

Power interruptions shouldn’t disrupt your schedule.Ā An energy storage system will keep your solar system operating during grid outages.Ā When paired with solar panels, anĀ energy storageĀ system supplies unlimited energy delivery. The solar panels power your home during the day and use any excess power to charge the battery. At night, theĀ systemĀ keeps your space bright. When used without solar panels, power outage support is dependent on battery size and your energy use. Batteries providing at least 12 hours of backup power are safest.

4) Are home energy storage systems financially beneficial?

You can use the energy storage to shelve your peak usage. When electricity is at its lowest daily rate, our smartĀ energy storageĀ uses that period to charge. During the peak periods, ourĀ energy storage systemĀ can power your home, reducing your electricity bill. Clients with solar panel installations enjoy a faster return on investment.

5) Do I receive incentives on my energy storage system?

If your energy storage is powered by solar panels, you are eligible for 30% federal tax credit. Many states and utilities provide rebates for homes and businesses with energy storage systems, aiming for grid resilience.